Programs & Examples On #Delimited

EXEC sp_executesql with multiple parameters

If one need to use the sp_executesql with OUTPUT variables:

EXEC sp_executesql @sql
                  ,N'@p0 INT'
                  ,N'@p1 INT OUTPUT'
                  ,N'@p2 VARCHAR(12) OUTPUT' 
                  ,@p0
                  ,@p1 OUTPUT
                  ,@p2 OUTPUT;

Reading tab-delimited file with Pandas - works on Windows, but not on Mac

The biggest clue is the rows are all being returned on one line. This indicates line terminators are being ignored or are not present.

You can specify the line terminator for csv_reader. If you are on a mac the lines created will end with \rrather than the linux standard \n or better still the suspenders and belt approach of windows with \r\n.

pandas.read_csv(filename, sep='\t', lineterminator='\r')

You could also open all your data using the codecs package. This may increase robustness at the expense of document loading speed.

import codecs

doc = codecs.open('document','rU','UTF-16') #open for reading with "universal" type set

df = pandas.read_csv(doc, sep='\t')

Create hive table using "as select" or "like" and also specify delimiter

Both the answers provided above work fine.

  1. CREATE TABLE person AS select * from employee;
  2. CREATE TABLE person LIKE employee;

Extracting columns from text file with different delimiters in Linux

If the command should work with both tabs and spaces as the delimiter I would use awk:

awk '{print $100,$101,$102,$103,$104,$105}' myfile > outfile

As long as you just need to specify 5 fields it is imo ok to just type them, for longer ranges you can use a for loop:

awk '{for(i=100;i<=105;i++)print $i}' myfile > outfile

If you want to use cut, you need to use the -f option:

cut -f100-105 myfile > outfile

If the field delimiter is different from TAB you need to specify it using -d:

cut -d' ' -f100-105 myfile > outfile

Check the man page for more info on the cut command.

Confusing error in R: Error in scan(file, what, nmax, sep, dec, quote, skip, nlines, na.strings, : line 1 did not have 42 elements)

To read characters try

scan("/PathTo/file.csv", "")

If you're reading numeric values, then just use

scan("/PathTo/file.csv")

scan by default will use white space as separator. The type of the second arg defines 'what' to read (defaults to double()).

How to get coordinates of an svg element?

i can handle it like that ;

svg.selectAll("rect")
    .data(zones)
    .enter()
    .append("rect")
    .attr("id", function (d) { return "zone" + d.zone; })
    .attr("class", "zone")
    .attr("x", function (d, i) {
        if (parseInt(i / (wcount)) % 2 == 0) {
            this.xcor = (i % wcount) * zoneW;
        }
        else {
            this.xcor = (zoneW * (wcount - 1)) - ((i % wcount) * zoneW);
        }

        return this.xcor;
    })

and anymore you can find x coordinate

svg.select("#zone1").on("click",function(){alert(this.xcor});

DateTime.ToString("MM/dd/yyyy HH:mm:ss.fff") resulted in something like "09/14/2013 07.20.31.371"

I bumped into this problem lately with Windows 10 from another direction, and found the answer from @JonSkeet very helpful in solving my problem.

I also did som further research with a test form and found that when the the current culture was set to "no" or "nb-NO" at runtime (Thread.CurrentThread.CurrentCulture = new CultureInfo("no");), the ToString("yyyy-MM-dd HH:mm:ss") call responded differently in Windows 7 and Windows 10. It returned what I expected in Windows 7 and HH.mm.ss in Windows 10!

I think this is a bit scary! Since I believed that a culture was a culture in any Windows version at least.

Comma separated results in SQL

this works in sql server 2016

USE AdventureWorks
GO
DECLARE @listStr VARCHAR(MAX)
SELECT @listStr = COALESCE(@listStr+',' ,'') + Name
FROM Production.Product
SELECT @listStr
GO

here-document gives 'unexpected end of file' error

The EOF token must be at the beginning of the line, you can't indent it along with the block of code it goes with.

If you write <<-EOF you may indent it, but it must be indented with Tab characters, not spaces. So it still might not end up even with the block of code.

Also make sure you have no whitespace after the EOF token on the line.

Writing a pandas DataFrame to CSV file

it could be not the answer for this case, but as I had the same error-message with .to_csvI tried .toCSV('name.csv') and the error-message was different ("SparseDataFrame' object has no attribute 'toCSV'). So the problem was solved by turning dataframe to dense dataframe

df.to_dense().to_csv("submission.csv", index = False, sep=',', encoding='utf-8')

Read a Csv file with powershell and capture corresponding data

So I figured out what is wrong with this statement:

Import-Csv H:\Programs\scripts\SomeText.csv |`

(Original)

Import-Csv H:\Programs\scripts\SomeText.csv -Delimiter "|"

(Proposed, You must use quotations; otherwise, it will not work and ISE will give you an error)

It requires the -Delimiter "|", in order for the variable to be populated with an array of items. Otherwise, Powershell ISE does not display the list of items.

I cannot say that I would recommend the | operator, since it is used to pipe cmdlets into one another.

I still cannot get the if statement to return true and output the values entered via the prompt.

If anyone else can help, it would be great. I still appreciate the post, it has been very helpful!

Shell script not running, command not found

I'm new to shell scripting too, but I had this same issue. Make sure at the end of your script you have a blank line. Otherwise it won't work.

Need to ZIP an entire directory using Node.js

Adm-zip has problems just compressing an existing archive https://github.com/cthackers/adm-zip/issues/64 as well as corruption with compressing binary files.

I've also ran into compression corruption issues with node-zip https://github.com/daraosn/node-zip/issues/4

node-archiver is the only one that seems to work well to compress but it doesn't have any uncompress functionality.

Splitting string into multiple rows in Oracle

There is a huge difference between the below two:

  • splitting a single delimited string
  • splitting delimited strings for multiple rows in a table.

If you do not restrict the rows, then the CONNECT BY clause would produce multiple rows and will not give the desired output.

Apart from Regular Expressions, a few other alternatives are using:

  • XMLTable
  • MODEL clause

Setup

SQL> CREATE TABLE t (
  2    ID          NUMBER GENERATED ALWAYS AS IDENTITY,
  3    text        VARCHAR2(100)
  4  );

Table created.

SQL>
SQL> INSERT INTO t (text) VALUES ('word1, word2, word3');

1 row created.

SQL> INSERT INTO t (text) VALUES ('word4, word5, word6');

1 row created.

SQL> INSERT INTO t (text) VALUES ('word7, word8, word9');

1 row created.

SQL> COMMIT;

Commit complete.

SQL>
SQL> SELECT * FROM t;

        ID TEXT
---------- ----------------------------------------------
         1 word1, word2, word3
         2 word4, word5, word6
         3 word7, word8, word9

SQL>

Using XMLTABLE:

SQL> SELECT id,
  2         trim(COLUMN_VALUE) text
  3  FROM t,
  4    xmltable(('"'
  5    || REPLACE(text, ',', '","')
  6    || '"'))
  7  /

        ID TEXT
---------- ------------------------
         1 word1
         1 word2
         1 word3
         2 word4
         2 word5
         2 word6
         3 word7
         3 word8
         3 word9

9 rows selected.

SQL>

Using MODEL clause:

SQL> WITH
  2  model_param AS
  3     (
  4            SELECT id,
  5                      text AS orig_str ,
  6                   ','
  7                          || text
  8                          || ','                                 AS mod_str ,
  9                   1                                             AS start_pos ,
 10                   Length(text)                                   AS end_pos ,
 11                   (Length(text) - Length(Replace(text, ','))) + 1 AS element_count ,
 12                   0                                             AS element_no ,
 13                   ROWNUM                                        AS rn
 14            FROM   t )
 15     SELECT   id,
 16              trim(Substr(mod_str, start_pos, end_pos-start_pos)) text
 17     FROM     (
 18                     SELECT *
 19                     FROM   model_param MODEL PARTITION BY (id, rn, orig_str, mod_str)
 20                     DIMENSION BY (element_no)
 21                     MEASURES (start_pos, end_pos, element_count)
 22                     RULES ITERATE (2000)
 23                     UNTIL (ITERATION_NUMBER+1 = element_count[0])
 24                     ( start_pos[ITERATION_NUMBER+1] = instr(cv(mod_str), ',', 1, cv(element_no)) + 1,
 25                     end_pos[iteration_number+1] = instr(cv(mod_str), ',', 1, cv(element_no) + 1) )
 26                 )
 27     WHERE    element_no != 0
 28     ORDER BY mod_str ,
 29           element_no
 30  /

        ID TEXT
---------- --------------------------------------------------
         1 word1
         1 word2
         1 word3
         2 word4
         2 word5
         2 word6
         3 word7
         3 word8
         3 word9

9 rows selected.

SQL>

Export table from database to csv file

Dead horse perhaps, but a while back I was trying to do the same and came across a script to create a STP that tried to do what I was looking for, but it had a few quirks that needed some attention. In an attempt to track down where I found the script to post an update, I came across this thread and it seemed like a good spot to share it.

This STP (Which for the most part I take no credit for, and I can't find the site I found it on), takes a schema name, table name, and Y or N [to include or exclude headers] as input parameters and queries the supplied table, outputting each row in comma-separated, quoted, csv format.

I've made numerous fixes/changes to the original script, but the bones of it are from the OP, whoever that was.

Here is the script:

IF OBJECT_ID('get_csvFormat', 'P') IS NOT NULL
    DROP PROCEDURE get_csvFormat
GO

CREATE PROCEDURE get_csvFormat(@schemaname VARCHAR(20), @tablename VARCHAR(30),@header char(1))
AS
BEGIN
    IF ISNULL(@tablename, '') = ''
    BEGIN
        PRINT('NO TABLE NAME SUPPLIED, UNABLE TO CONTINUE')
        RETURN
    END
    ELSE
    BEGIN
        DECLARE @cols VARCHAR(MAX), @sqlstrs VARCHAR(MAX), @heading VARCHAR(MAX), @schemaid int

        --if no schemaname provided, default to dbo
        IF ISNULL(@schemaname, '') = ''
            SELECT @schemaname = 'dbo'

        --if no header provided, default to Y
        IF ISNULL(@header, '') = ''
            SELECT @header = 'Y'

        SELECT @schemaid = (SELECT schema_id FROM sys.schemas WHERE [name] = @schemaname)
        SELECT 
        @cols = (
            SELECT ' , CAST([', b.name + '] AS VARCHAR(50)) '  
            FROM sys.objects a 
            INNER JOIN sys.columns b ON a.object_id=b.object_id 
            WHERE a.name = @tablename AND a.schema_id = @schemaid
            FOR XML PATH('')
        ),
        @heading = (
            SELECT ',"' + b.name + '"' FROM sys.objects a 
            INNER JOIN sys.columns b ON a.object_id=b.object_id 
            WHERE a.name= @tablename AND a.schema_id = @schemaid
            FOR XML PATH('')
        )

        SET @tablename = @schemaname + '.' + @tablename
        SET @heading =  'SELECT ''' + right(@heading,len(@heading)-1) + ''' AS CSV, 0 AS Sort'  + CHAR(13)
        SET @cols =  '''"'',' + replace(right(@cols,len(@cols)-1),',', ',''","'',') + ',''"''' + CHAR(13)

        IF @header = 'Y'
            SET @sqlstrs =  'SELECT CSV FROM (' + CHAR(13) + @heading + ' UNION SELECT CONCAT(' + @cols + ') CSV, 1 AS Sort FROM ' + @tablename + CHAR(13) + ') X ORDER BY Sort, CSV ASC'
        ELSE
            SET @sqlstrs =  'SELECT CONCAT(' + @cols + ') CSV FROM ' + @tablename 

        IF @schemaid IS NOT NULL 
            EXEC(@sqlstrs)
        ELSE 
            PRINT('SCHEMA DOES NOT EXIST')
    END
END

GO

--------------------------------------

--EXEC get_csvFormat @schemaname='dbo', @tablename='TradeUnion', @header='Y'

Writelines writes lines without newline, Just fills the file

This is actually a pretty common problem for newcomers to Python—especially since, across the standard library and popular third-party libraries, some reading functions strip out newlines, but almost no writing functions (except the log-related stuff) add them.

So, there's a lot of Python code out there that does things like:

fw.write('\n'.join(line_list) + '\n')

or

fw.write(line + '\n' for line in line_list)

Either one is correct, and of course you could even write your own writelinesWithNewlines function that wraps it up…

But you should only do this if you can't avoid it.

It's better if you can create/keep the newlines in the first place—as in Greg Hewgill's suggestions:

line_list.append(new_line + "\n")

And it's even better if you can work at a higher level than raw lines of text, e.g., by using the csv module in the standard library, as esuaro suggests.

For example, right after defining fw, you might do this:

cw = csv.writer(fw, delimiter='|')

Then, instead of this:

new_line = d[looking_for]+'|'+'|'.join(columns[1:])
line_list.append(new_line)

You do this:

row_list.append(d[looking_for] + columns[1:])

And at the end, instead of this:

fw.writelines(line_list)

You do this:

cw.writerows(row_list)

Finally, your design is "open a file, then build up a list of lines to add to the file, then write them all at once". If you're going to open the file up top, why not just write the lines one by one? Whether you're using simple writes or a csv.writer, it'll make your life simpler, and your code easier to read. (Sometimes there can be simplicity, efficiency, or correctness reasons to write a file all at once—but once you've moved the open all the way to the opposite end of the program from the write, you've pretty much lost any benefits of all-at-once.)

Hive load CSV with commas in quoted fields

Add a backward slash in FIELDS TERMINATED BY '\;'

For Example:

CREATE  TABLE demo_table_1_csv
COMMENT 'my_csv_table 1'
ROW FORMAT DELIMITED
FIELDS TERMINATED BY '\;'
LINES TERMINATED BY '\n'
STORED AS TEXTFILE
LOCATION 'your_hdfs_path'
AS 
select a.tran_uuid,a.cust_id,a.risk_flag,a.lookback_start_date,a.lookback_end_date,b.scn_name,b.alerted_risk_category,
CASE WHEN (b.activity_id is not null ) THEN 1 ELSE 0 END as Alert_Flag 
FROM scn1_rcc1_agg as a LEFT OUTER JOIN scenario_activity_alert as b ON a.tran_uuid = b.activity_id;

I have tested it, and it worked.

How to import data from text file to mysql database

Walkthrough on using MySQL's LOAD DATA command:

  1. Create your table:

    CREATE TABLE foo(myid INT, mymessage VARCHAR(255), mydecimal DECIMAL(8,4));
    
  2. Create your tab delimited file (note there are tabs between the columns):

    1   Heart disease kills     1.2
    2   one out of every two    2.3
    3   people in America.      4.5
    
  3. Use the load data command:

    LOAD DATA LOCAL INFILE '/tmp/foo.txt' 
    INTO TABLE foo COLUMNS TERMINATED BY '\t';
    

    If you get a warning that this command can't be run, then you have to enable the --local-infile=1 parameter described here: How can I correct MySQL Load Error

  4. The rows get inserted:

    Query OK, 3 rows affected (0.00 sec)
    Records: 3  Deleted: 0  Skipped: 0  Warnings: 0
    
  5. Check if it worked:

    mysql> select * from foo;
    +------+----------------------+-----------+
    | myid | mymessage            | mydecimal |
    +------+----------------------+-----------+
    |    1 | Heart disease kills  |    1.2000 |
    |    2 | one out of every two |    2.3000 |
    |    3 | people in America.   |    4.5000 |
    +------+----------------------+-----------+
    3 rows in set (0.00 sec)
    

How to specify which columns to load your text file columns into:

Like this:

LOAD DATA LOCAL INFILE '/tmp/foo.txt' INTO TABLE foo
FIELDS TERMINATED BY '\t' LINES TERMINATED BY '\n'
(@col1,@col2,@col3) set myid=@col1,mydecimal=@col3;

The file contents get put into variables @col1, @col2, @col3. myid gets column 1, and mydecimal gets column 3. If this were run, it would omit the second row:

mysql> select * from foo;
+------+-----------+-----------+
| myid | mymessage | mydecimal |
+------+-----------+-----------+
|    1 | NULL      |    1.2000 |
|    2 | NULL      |    2.3000 |
|    3 | NULL      |    4.5000 |
+------+-----------+-----------+
3 rows in set (0.00 sec)

WooCommerce return product object by id

Use this method:

$_product = wc_get_product( $id );

Official API-docs: wc_get_product

How should I escape commas and speech marks in CSV files so they work in Excel?

We eventually found the answer to this.

Excel will only respect the escaping of commas and speech marks if the column value is NOT preceded by a space. So generating the file without spaces like this...

Reference,Title,Description
1,"My little title","My description, which may contain ""speech marks"" and commas."
2,"My other little title","My other description, which may also contain ""speech marks"" and commas."

... fixed the problem. Hope this helps someone!

Convert text to columns in Excel using VBA

If someone is facing issue using texttocolumns function in UFT. Please try using below function.

myxl.Workbooks.Open myexcel.xls
myxl.Application.Visible = false `enter code here`
set mysheet = myxl.ActiveWorkbook.Worksheets(1)
Set objRange = myxl.Range("A1").EntireColumn
Set objRange2 = mysheet.Range("A1")
objRange.TextToColumns objRange2,1,1, , , , true

Here we are using coma(,) as delimiter.

How to output a comma delimited list in jinja python template?

you could also use the builtin "join" filter (http://jinja.pocoo.org/docs/templates/#join like this:

{{ users|join(', ') }}

Text File Parsing with Python

I would use a for loop to iterate over the lines in the text file:

for line in my_text:
    outputfile.writelines(data_parser(line, reps))

If you want to read the file line-by-line instead of loading the whole thing at the start of the script you could do something like this:

inputfile = open('test.dat')
outputfile = open('test.csv', 'w')

# sample text string, just for demonstration to let you know how the data looks like
# my_text = '"2012-06-23 03:09:13.23",4323584,-1.911224,-0.4657288,-0.1166382,-0.24823,0.256485,"NAN",-0.3489428,-0.130449,-0.2440527,-0.2942413,0.04944348,0.4337797,-1.105218,-1.201882,-0.5962594,-0.586636'

# dictionary definition 0-, 1- etc. are there to parse the date block delimited with dashes, and make sure the negative numbers are not effected
reps = {'"NAN"':'NAN', '"':'', '0-':'0,','1-':'1,','2-':'2,','3-':'3,','4-':'4,','5-':'5,','6-':'6,','7-':'7,','8-':'8,','9-':'9,', ' ':',', ':':',' }

for i in range(4): inputfile.next() # skip first four lines
for line in inputfile:
    outputfile.writelines(data_parser(line, reps))

inputfile.close()
outputfile.close()

How to split a comma-separated value to columns

I found that using PARSENAME as above caused any name with a period to get nulled.

So if there was an initial or a title in the name followed by a dot they return NULL.

I found this worked for me:

SELECT 
REPLACE(SUBSTRING(FullName, 1,CHARINDEX(',', FullName)), ',','') as Name,
REPLACE(SUBSTRING(FullName, CHARINDEX(',', FullName), LEN(FullName)), ',', '') as Surname
FROM Table1

Open CSV file via VBA (performance)

Sometimes all the solutions with Workbooks.open is not working no matter how many parameters are set. For me, the fastest solution was to change the List separator in Region & language settings. Region window / Additional settings... / List separator.

If csv is not opening in proper way You probly have set ',' as a list separator. Just change it to ';' and everything is solved. Just the easiest way when "everything is against You" :P

How to split() a delimited string to a List<String>

Either use:

List<string> list = new List<string>(array);

or from LINQ:

List<string> list = array.ToList();

Or change your code to not rely on the specific implementation:

IList<string> list = array; // string[] implements IList<string>

sqlplus error on select from external table: ORA-29913: error in executing ODCIEXTTABLEOPEN callout

We had this error on Oracle RAC 11g on Windows, and the solution was to create the same OS directory tree and external file on both nodes.

How to send email to multiple recipients using python smtplib?

It works for me.

import smtplib
from email.mime.text import MIMEText

s = smtplib.SMTP('smtp.uk.xensource.com')
s.set_debuglevel(1)
msg = MIMEText("""body""")
sender = '[email protected]'
recipients = '[email protected],[email protected]'
msg['Subject'] = "subject line"
msg['From'] = sender
msg['To'] = recipients
s.sendmail(sender, recipients.split(','), msg.as_string())

C# DateTime.ParseExact

That's because you have the Date in American format in line[i] and UK format in the FormatString.

11/20/2011
M / d/yyyy

I'm guessing you might need to change the FormatString to:

"M/d/yyyy h:mm"

Convert a space delimited string to list

states = "Alaska Alabama Arkansas American Samoa Arizona California Colorado"
states_list = states.split (' ')

Format output string, right alignment

It can be achieved by using rjust:

line_new = word[0].rjust(10) + word[1].rjust(10) + word[2].rjust(10)

How to split a delimited string into an array in awk?

To split a string to an array in awk we use the function split():

 awk '{split($0, a, ":")}'
 #           ^^  ^  ^^^
 #            |  |   |
 #       string  |   delimiter
 #               |
 #               array to store the pieces

If no separator is given, it uses the FS, which defaults to the space:

$ awk '{split($0, a); print a[2]}' <<< "a:b c:d e"
c:d

We can give a separator, for example ::

$ awk '{split($0, a, ":"); print a[2]}' <<< "a:b c:d e"
b c

Which is equivalent to setting it through the FS:

$ awk -F: '{split($0, a); print a[1]}' <<< "a:b c:d e"
b c

In gawk you can also provide the separator as a regexp:

$ awk '{split($0, a, ":*"); print a[2]}' <<< "a:::b c::d e" #note multiple :
b c

And even see what the delimiter was on every step by using its fourth parameter:

$ awk '{split($0, a, ":*", sep); print a[2]; print sep[1]}' <<< "a:::b c::d e"
b c
:::

Let's quote the man page of GNU awk:

split(string, array [, fieldsep [, seps ] ])

Divide string into pieces separated by fieldsep and store the pieces in array and the separator strings in the seps array. The first piece is stored in array[1], the second piece in array[2], and so forth. The string value of the third argument, fieldsep, is a regexp describing where to split string (much as FS can be a regexp describing where to split input records). If fieldsep is omitted, the value of FS is used. split() returns the number of elements created. seps is a gawk extension, with seps[i] being the separator string between array[i] and array[i+1]. If fieldsep is a single space, then any leading whitespace goes into seps[0] and any trailing whitespace goes into seps[n], where n is the return value of split() (i.e., the number of elements in array).

Extract specific columns from delimited file using Awk

Tabulator is a set of unix command line tools to work with csv files that have header lines. Here is an example to extract columns by name from a file test.csv:

name,sex,house_nr,height,shoe_size
arthur,m,42,181,11.5
berta,f,101,163,8.5
chris,m,1333,175,10
don,m,77,185,12.5
elisa,f,204,166,7

Then tblmap -k name,height test.csv produces

name,height
arthur,181
berta,163
chris,175
don,185
elisa,166

Parsing CSV / tab-delimited txt file with Python

If the file is large, you may not want to load it entirely into memory at once. This approach avoids that. (Of course, making a dict out of it could still take up some RAM, but it's guaranteed to be smaller than the original file.)

my_dict = {}
for i, line in enumerate(file):
    if (i - 8) % 7:
        continue
    k, v = line.split("\t")[:3:2]
    my_dict[k] = v

Edit: Not sure where I got extend from before. I meant update

How to convert comma-delimited string to list in Python?

In the case of integers that are included at the string, if you want to avoid casting them to int individually you can do:

mList = [int(e) if e.isdigit() else e for e in mStr.split(',')]

It is called list comprehension, and it is based on set builder notation.

ex:

>>> mStr = "1,A,B,3,4"
>>> mList = [int(e) if e.isdigit() else e for e in mStr.split(',')]
>>> mList
>>> [1,'A','B',3,4]

Writing List of Strings to Excel CSV File in Python

Very simple to fix, you just need to turn the parameter to writerow into a list.

for item in RESULTS:
     wr.writerow([item,])

Extract the last substring from a cell

This works, even when there are middle names:

=MID(A2,FIND(CHAR(1),SUBSTITUTE(A2," ",CHAR(1),LEN(A2)-LEN(SUBSTITUTE(A2," ",""))))+1,LEN(A2))

If you want everything BUT the last name, check out this answer.

If there are trailing spaces in your names, then you may want to remove them by replacing all instances of A2 by TRIM(A2) in the above formula.

Note that it is only by pure chance that your first formula =RIGHT(A2,FIND(" ",A2,1)-1) kind of works for Alistair Stevens. This is because "Alistair" and " Stevens" happen to contain the same number of characters (if you count the leading space in " Stevens").

How can I split this comma-delimited string in Python?

How about a list?

mystring.split(",")

It might help if you could explain what kind of info we are looking at. Maybe some background info also?

EDIT:

I had a thought you might want the info in groups of two?

then try:

re.split(r"\d*,\d*", mystring)

and also if you want them into tuples

[(pair[0], pair[1]) for match in re.split(r"\d*,\d*", mystring) for pair in match.split(",")]

in a more readable form:

mylist = []
for match in re.split(r"\d*,\d*", mystring):
    for pair in match.split(",")
        mylist.append((pair[0], pair[1]))

Where value in column containing comma delimited values

SELECT * FROM TABLE_NAME WHERE
        (
            LOCATE(',DOG,', CONCAT(',',COLUMN,','))>0 OR
            LOCATE(',CAT,', CONCAT(',',COLUMN,','))>0
        );

How to convert a string with comma-delimited items to a list in Python?

Just to add on to the existing answers: hopefully, you'll encounter something more like this in the future:

>>> word = 'abc'
>>> L = list(word)
>>> L
['a', 'b', 'c']
>>> ''.join(L)
'abc'

But what you're dealing with right now, go with @Cameron's answer.

>>> word = 'a,b,c'
>>> L = word.split(',')
>>> L
['a', 'b', 'c']
>>> ','.join(L)
'a,b,c'

jQuery $.ajax request of dataType json will not retrieve data from PHP script

I think I know this one...

Try sending your JSON as JSON by using PHP's header() function:

/**
 * Send as JSON
 */
header("Content-Type: application/json", true);

Though you are passing valid JSON, jQuery's $.ajax doesn't think so because it's missing the header.

jQuery used to be fine without the header, but it was changed a few versions back.

ALSO

Be sure that your script is returning valid JSON. Use Firebug or Google Chrome's Developer Tools to check the request's response in the console.

UPDATE

You will also want to update your code to sanitize the $_POST to avoid sql injection attacks. As well as provide some error catching.

if (isset($_POST['get_member'])) {

    $member_id = mysql_real_escape_string ($_POST["get_member"]);

    $query = "SELECT * FROM `members` WHERE `id` = '" . $member_id . "';";

    if ($result = mysql_query( $query )) {

       $row = mysql_fetch_array($result);

       $type = $row['type'];
       $name = $row['name'];
       $fname = $row['fname'];
       $lname = $row['lname'];
       $email = $row['email'];
       $phone = $row['phone'];
       $website = $row['website'];
       $image = $row['image'];

       /* JSON Row */
       $json = array( "type" => $type, "name" => $name, "fname" => $fname, "lname" => $lname, "email" => $email, "phone" => $phone, "website" => $website, "image" => $image );

    } else {

        /* Your Query Failed, use mysql_error to report why */
        $json = array('error' => 'MySQL Query Error');

    }

     /* Send as JSON */
     header("Content-Type: application/json", true);

    /* Return JSON */
    echo json_encode($json);

    /* Stop Execution */
    exit;

}

MySQL query finding values in a comma separated string

If the set of colors is more or less fixed, the most efficient and also most readable way would be to use string constants in your app and then use MySQL's SET type with FIND_IN_SET('red',colors) in your queries. When using the SET type with FIND_IN_SET, MySQL uses one integer to store all values and uses binary "and" operation to check for presence of values which is way more efficient than scanning a comma-separated string.

In SET('red','blue','green'), 'red' would be stored internally as 1, 'blue' would be stored internally as 2 and 'green' would be stored internally as 4. The value 'red,blue' would be stored as 3 (1|2) and 'red,green' as 5 (1|4).

Convert string to List<string> in one line?

If you already have a list and want to add values from a delimited string, you can use AddRange or InsertRange. For example:

existingList.AddRange(names.Split(','));

R: invalid multibyte string

I had a similarly strange problem with a file from the program e-prime (edat -> SPSS conversion), but then I discovered that there are many additional encodings you can use. this did the trick for me:

tbl <- read.delim("dir/file.txt", fileEncoding="UCS-2LE")

How to cut first n and last n columns?

Try the following:

echo a#b#c | awk -F"#" '{$1 = ""; $NF = ""; print}' OFS=""

Getting the count of unique values in a column in bash

The GNU site suggests this nice awk script, which prints both the words and their frequency.

Possible changes:

  • You can pipe through sort -nr (and reverse word and freq[word]) to see the result in descending order.
  • If you want a specific column, you can omit the for loop and simply write freq[3]++ - replace 3 with the column number.

Here goes:

 # wordfreq.awk --- print list of word frequencies

 {
     $0 = tolower($0)    # remove case distinctions
     # remove punctuation
     gsub(/[^[:alnum:]_[:blank:]]/, "", $0)
     for (i = 1; i <= NF; i++)
         freq[$i]++
 }

 END {
     for (word in freq)
         printf "%s\t%d\n", word, freq[word]
 }

How do I import CSV file into a MySQL table?

I see something strange. You are using for ESCAPING the same character you use for ENCLOSING. So the engine does not know what to do when it founds a '"' and I think that is why nothing seems to be in the right place. I think that if you remove the line of ESCAPING, should run great. Like:

LOAD DATA INFILE "/home/paul/clientdata.csv"
INTO TABLE CSVImport
COLUMNS TERMINATED BY ','
OPTIONALLY ENCLOSED BY '"'
LINES TERMINATED BY '\n'
IGNORE 1 LINES;

Unless you analyze (manually, visually, ... ) your CSV and find which character uses for escape. Sometimes is '\'. But if you do not have it, do not use it.

How do I use System.getProperty("line.separator").toString()?

The other responders are correct that split() takes a regex as the argument, so you'll have to fix that first. The other problem is that you're assuming that the line break characters are the same as the system default. Depending on where the data is coming from, and where the program is running, this assumption may not be correct.

How to count number of unique values of a field in a tab-delimited text file?

This script outputs the number of unique values in each column of a given file. It assumes that first line of given file is header line. There is no need for defining number of fields. Simply save the script in a bash file (.sh) and provide the tab delimited file as a parameter to this script.

Code

#!/bin/bash

awk '
(NR==1){
    for(fi=1; fi<=NF; fi++)
        fname[fi]=$fi;
} 
(NR!=1){
    for(fi=1; fi<=NF; fi++) 
        arr[fname[fi]][$fi]++;
} 
END{
    for(fi=1; fi<=NF; fi++){
        out=fname[fi];
        for (item in arr[fname[fi]])
            out=out"\t"item"_"arr[fname[fi]][item];
        print(out);
    }
}
' $1

Execution Example:

bash> ./script.sh <path to tab-delimited file>

Output Example

isRef    A_15      C_42     G_24     T_18
isCar    YEA_10    NO_40    NA_50
isTv     FALSE_33  TRUE_66

Notepad++ Multi editing

Yes: simply press and hold the Alt key, click and drag to select the lines whose columns you wish to edit, and begin typing.

You can also go to Settings > Preferences..., and in the Editing tab, turn on multi-editing, to enable selection of multiple separate regions or columns of text to edit at once.

It's much more intuitive, as you can see your edits live as you type.

Easiest way to parse a comma delimited string to some kind of object I can loop through to access the individual values?

Use Linq, it is a very quick and easy way.

string mystring = "0, 10, 20, 30, 100, 200";

var query = from val in mystring.Split(',')
            select int.Parse(val);
foreach (int num in query)
{
     Console.WriteLine(num);
}

How to split a string, but also keep the delimiters?

I had a look at the above answers and honestly none of them I find satisfactory. What you want to do is essentially mimic the Perl split functionality. Why Java doesn't allow this and have a join() method somewhere is beyond me but I digress. You don't even need a class for this really. Its just a function. Run this sample program:

Some of the earlier answers have excessive null-checking, which I recently wrote a response to a question here:

https://stackoverflow.com/users/18393/cletus

Anyway, the code:

public class Split {
    public static List<String> split(String s, String pattern) {
        assert s != null;
        assert pattern != null;
        return split(s, Pattern.compile(pattern));
    }

    public static List<String> split(String s, Pattern pattern) {
        assert s != null;
        assert pattern != null;
        Matcher m = pattern.matcher(s);
        List<String> ret = new ArrayList<String>();
        int start = 0;
        while (m.find()) {
            ret.add(s.substring(start, m.start()));
            ret.add(m.group());
            start = m.end();
        }
        ret.add(start >= s.length() ? "" : s.substring(start));
        return ret;
    }

    private static void testSplit(String s, String pattern) {
        System.out.printf("Splitting '%s' with pattern '%s'%n", s, pattern);
        List<String> tokens = split(s, pattern);
        System.out.printf("Found %d matches%n", tokens.size());
        int i = 0;
        for (String token : tokens) {
            System.out.printf("  %d/%d: '%s'%n", ++i, tokens.size(), token);
        }
        System.out.println();
    }

    public static void main(String args[]) {
        testSplit("abcdefghij", "z"); // "abcdefghij"
        testSplit("abcdefghij", "f"); // "abcde", "f", "ghi"
        testSplit("abcdefghij", "j"); // "abcdefghi", "j", ""
        testSplit("abcdefghij", "a"); // "", "a", "bcdefghij"
        testSplit("abcdefghij", "[bdfh]"); // "a", "b", "c", "d", "e", "f", "g", "h", "ij"
    }
}

String concatenation in Jinja

You can use + if you know all the values are strings. Jinja also provides the ~ operator, which will ensure all values are converted to string first.

{% set my_string = my_string ~ stuff ~ ', '%}

Parsing a comma-delimited std::string

You could also use the following function.

void tokenize(const string& str, vector<string>& tokens, const string& delimiters = ",")
{
  // Skip delimiters at beginning.
  string::size_type lastPos = str.find_first_not_of(delimiters, 0);

  // Find first non-delimiter.
  string::size_type pos = str.find_first_of(delimiters, lastPos);

  while (string::npos != pos || string::npos != lastPos) {
    // Found a token, add it to the vector.
    tokens.push_back(str.substr(lastPos, pos - lastPos));

    // Skip delimiters.
    lastPos = str.find_first_not_of(delimiters, pos);

    // Find next non-delimiter.
    pos = str.find_first_of(delimiters, lastPos);
  }
}

Converting a generic list to a CSV string

The problem with String.Join is that you are not handling the case of a comma already existing in the value. When a comma exists then you surround the value in Quotes and replace all existing Quotes with double Quotes.

String.Join(",",{"this value has a , in it","This one doesn't", "This one , does"});

See CSV Module

Improve INSERT-per-second performance of SQLite

Avoid sqlite3_clear_bindings(stmt).

The code in the test sets the bindings every time through which should be enough.

The C API intro from the SQLite docs says:

Prior to calling sqlite3_step() for the first time or immediately after sqlite3_reset(), the application can invoke the sqlite3_bind() interfaces to attach values to the parameters. Each call to sqlite3_bind() overrides prior bindings on the same parameter

There is nothing in the docs for sqlite3_clear_bindings saying you must call it in addition to simply setting the bindings.

More detail: Avoid_sqlite3_clear_bindings()

String parsing in Java with delimiter tab "\t" using split

You can use yourstring.split("\x09"); I tested it, and it works.

How to parse a CSV in a Bash script?

CSV isn't quite that simple. Depending on the limits of the data you have, you might have to worry about quoted values (which may contain commas and newlines) and escaping quotes.

So if your data are restricted enough can get away with simple comma-splitting fine, shell script can do that easily. If, on the other hand, you need to parse CSV ‘properly’, bash would not be my first choice. Instead I'd look at a higher-level scripting language, for example Python with a csv.reader.

Regex for Comma delimited list

i used this for a list of items that had to be alphanumeric without underscores at the front of each item.

^(([0-9a-zA-Z][0-9a-zA-Z_]*)([,][0-9a-zA-Z][0-9a-zA-Z_]*)*)$

Import Package Error - Cannot Convert between Unicode and Non Unicode String Data Type

Not sure if this is still a problem but I found this simple solution:

  1. Right-Click Ole DB Source
  2. Select 'Edit'
  3. Select Input and Output Properties Tab
  4. Under "Inputs and Outputs", Expand "Ole DB Source Output" External Columns and Output Columns
  5. In Output columns, select offending field, on the right-hand panel ensure Data Type Property matches that of the field in External Columns properties

Hope this was clear and easy to follow

How can I split a delimited string into an array in PHP?

The Best choice is to use the function "explode()".

$content = "dad,fger,fgferf,fewf";
$delimiters =",";
$explodes = explode($delimiters, $content);

foreach($exploade as $explode) {
    echo "This is a exploded String: ". $explode;
}

If you want a faster approach you can use a delimiter tool like Delimiters.co There are many websites like this. But I prefer a simple PHP code.

How can I read and parse CSV files in C++?

The C++ String Toolkit Library (StrTk) has a token grid class that allows you to load data either from text files, strings or char buffers, and to parse/process them in a row-column fashion.

You can specify the row delimiters and column delimiters or just use the defaults.

void foo()
{
   std::string data = "1,2,3,4,5\n"
                      "0,2,4,6,8\n"
                      "1,3,5,7,9\n";

   strtk::token_grid grid(data,data.size(),",");

   for(std::size_t i = 0; i < grid.row_count(); ++i)
   {
      strtk::token_grid::row_type r = grid.row(i);
      for(std::size_t j = 0; j < r.size(); ++j)
      {
         std::cout << r.get<int>(j) << "\t";
      }
      std::cout << std::endl;
   }
   std::cout << std::endl;
}

More examples can be found Here

Sorting a tab delimited file

You need to put an actual tab character after the -t\ and to do that in a shell you hit ctrl-v and then the tab character. Most shells I've used support this mode of literal tab entry.

Beware, though, because copying and pasting from another place generally does not preserve tabs.

How to split a delimited string in Ruby and convert it to an array?

"1,2,3,4".split(",") as strings

"1,2,3,4".split(",").map { |s| s.to_i } as integers

Convert DataTable to CSV stream

I've used the following code, pillaged from someone's blog (pls forgive lack of citation). It takes care of quotations, newline and comma in a reasonably elegant way by quoting out each field value.

    /// <summary>
    /// Converts the passed in data table to a CSV-style string.      
    /// </summary>
    /// <param name="table">Table to convert</param>
    /// <returns>Resulting CSV-style string</returns>
    public static string ToCSV(this DataTable table)
    {
        return ToCSV(table, ",", true);
    }

    /// <summary>
    /// Converts the passed in data table to a CSV-style string.
    /// </summary>
    /// <param name="table">Table to convert</param>
    /// <param name="includeHeader">true - include headers<br/>
    /// false - do not include header column</param>
    /// <returns>Resulting CSV-style string</returns>
    public static string ToCSV(this DataTable table, bool includeHeader)
    {
        return ToCSV(table, ",", includeHeader);
    }

    /// <summary>
    /// Converts the passed in data table to a CSV-style string.
    /// </summary>
    /// <param name="table">Table to convert</param>
    /// <param name="includeHeader">true - include headers<br/>
    /// false - do not include header column</param>
    /// <returns>Resulting CSV-style string</returns>
     public static string ToCSV(this DataTable table, string delimiter, bool includeHeader)
    {
        var result = new StringBuilder();

        if (includeHeader)
        {
            foreach (DataColumn column in table.Columns)
            {
                result.Append(column.ColumnName);
                result.Append(delimiter);
            }

            result.Remove(--result.Length, 0);
            result.Append(Environment.NewLine);
        }

        foreach (DataRow row in table.Rows)
        {
            foreach (object item in row.ItemArray)
            {
                if (item is DBNull)
                    result.Append(delimiter);
                else
                {
                    string itemAsString = item.ToString();
                    // Double up all embedded double quotes
                    itemAsString = itemAsString.Replace("\"", "\"\"");

                    // To keep things simple, always delimit with double-quotes
                    // so we don't have to determine in which cases they're necessary
                    // and which cases they're not.
                    itemAsString = "\"" + itemAsString + "\"";

                    result.Append(itemAsString + delimiter);
                }
            }

            result.Remove(--result.Length, 0);
            result.Append(Environment.NewLine);
        }

        return result.ToString();
    }

Passing a varchar full of comma delimited values to a SQL Server IN function

If you use SQL Server 2008 or higher, use table valued parameters; for example:

CREATE PROCEDURE [dbo].[GetAccounts](@accountIds nvarchar)
AS
BEGIN
    SELECT * 
    FROM accountsTable 
    WHERE accountId IN (select * from @accountIds)
END

CREATE TYPE intListTableType AS TABLE (n int NOT NULL)

DECLARE @tvp intListTableType 

-- inserts each id to one row in the tvp table    
INSERT @tvp(n) VALUES (16509),(16685),(46173),(42925),(46167),(5511)

EXEC GetAccounts @tvp

A method to reverse effect of java String.split()?

For the sake of completeness, I'd like to add that you cannot reverse String#split in general, as it accepts a regular expression.

"hello__world".split("_+"); Yields ["hello", "world"].
"hello_world".split("_+"); Yields ["hello", "world"].

These yield identical results from a different starting point. splitting is not a one-to-one operation, and is thus non-reversible.

This all being said, if you assume your parameter to be a fixed string, not regex, then you can certainly do this using one of the many posted answers.

Split function equivalent in T-SQL?

This is another version which really does not have any restrictions (e.g.: special chars when using xml approach, number of records in CTE approach) and it runs much faster based on a test on 10M+ records with source string average length of 4000. Hope this could help.

Create function [dbo].[udf_split] (
    @ListString nvarchar(max),
    @Delimiter  nvarchar(1000),
    @IncludeEmpty bit) 
Returns @ListTable TABLE (ID int, ListValue nvarchar(1000))
AS
BEGIN
    Declare @CurrentPosition int, @NextPosition int, @Item nvarchar(max), @ID int, @L int
    Select @ID = 1,
   @L = len(replace(@Delimiter,' ','^')),
            @ListString = @ListString + @Delimiter,
            @CurrentPosition = 1 
    Select @NextPosition = Charindex(@Delimiter, @ListString, @CurrentPosition)
   While @NextPosition > 0 Begin
   Set  @Item = LTRIM(RTRIM(SUBSTRING(@ListString, @CurrentPosition, @NextPosition-@CurrentPosition)))
   If      @IncludeEmpty=1 or LEN(@Item)>0 Begin 
     Insert Into @ListTable (ID, ListValue) Values (@ID, @Item)
     Set @ID = @ID+1
   End
   Set  @CurrentPosition = @NextPosition+@L
   Set  @NextPosition = Charindex(@Delimiter, @ListString, @CurrentPosition)
  End
    RETURN
END

Best method for reading newline delimited files and discarding the newlines?

I'd do it like this:

f = open('test.txt')
l = [l for l in f.readlines() if l.strip()]
f.close()
print l

Can you split/explode a field in a MySQL query?

I've resolved this kind of problem with a regular expression pattern. They tend to be slower than regular queries but it's an easy way to retrieve data in a comma-delimited query column

SELECT * 
FROM `TABLE`
WHERE `field` REGEXP ',?[SEARCHED-VALUE],?';

the greedy question mark helps to search at the beggining or the end of the string.

Hope that helps for anyone in the future

How can I combine multiple rows into a comma-delimited list in Oracle?

The WM_CONCAT function (if included in your database, pre Oracle 11.2) or LISTAGG (starting Oracle 11.2) should do the trick nicely. For example, this gets a comma-delimited list of the table names in your schema:

select listagg(table_name, ', ') within group (order by table_name) 
  from user_tables;

or

select wm_concat(table_name) 
  from user_tables;

More details/options

Link to documentation

How to put more than 1000 values into an Oracle IN clause

Yes, very weird situation for oracle.

if you specify 2000 ids inside the IN clause, it will fail. this fails:

select ... 
where id in (1,2,....2000) 

but if you simply put the 2000 ids in another table (temp table for example), it will works below query:

select ... 
where id in (select userId 
             from temptable_with_2000_ids ) 

what you can do, actually could split the records into a lot of 1000 records and execute them group by group.

T-SQL: Opposite to string concatenation - how to split string into multiple records

I use this function (SQL Server 2005 and above).

create function [dbo].[Split]
(
    @string nvarchar(4000),
    @delimiter nvarchar(10)
)
returns @table table
(
    [Value] nvarchar(4000)
)
begin
    declare @nextString nvarchar(4000)
    declare @pos int, @nextPos int

    set @nextString = ''
    set @string = @string + @delimiter

    set @pos = charindex(@delimiter, @string)
    set @nextPos = 1
    while (@pos <> 0)
    begin
        set @nextString = substring(@string, 1, @pos - 1)

        insert into @table
        (
            [Value]
        )
        values
        (
            @nextString
        )

        set @string = substring(@string, @pos + len(@delimiter), len(@string))
        set @nextPos = @pos
        set @pos = charindex(@delimiter, @string)
    end
    return
end

How do I create a comma delimited string from an ArrayList?

The solutions so far are all quite complicated. The idiomatic solution should doubtless be:

String.Join(",", x.Cast(Of String)().ToArray())

There's no need for fancy acrobatics in new framework versions. Supposing a not-so-modern version, the following would be easiest:

Console.WriteLine(String.Join(",", CType(x.ToArray(GetType(String)), String())))

mspmsp's second solution is a nice approach as well but it's not working because it misses the AddressOf keyword. Also, Convert.ToString is rather inefficient (lots of unnecessary internal evaluations) and the Convert class is generally not very cleanly designed. I tend to avoid it, especially since it's completely redundant.

Relational Database Design Patterns?

There's a book in Martin Fowler's Signature Series called Refactoring Databases. That provides a list of techniques for refactoring databases. I can't say I've heard a list of database patterns so much.

I would also highly recommend David C. Hay's Data Model Patterns and the follow up A Metadata Map which builds on the first and is far more ambitious and intriguing. The Preface alone is enlightening.

Also a great place to look for some pre-canned database models is Len Silverston's Data Model Resource Book Series Volume 1 contains universally applicable data models (employees, accounts, shipping, purchases, etc), Volume 2 contains industry specific data models (accounting, healthcare, etc), Volume 3 provides data model patterns.

Finally, while this book is ostensibly about UML and Object Modelling, Peter Coad's Modeling in Color With UML provides an "archetype" driven process of entity modeling starting from the premise that there are 4 core archetypes of any object/data model

What's the best way to build a string of delimited items in Java?

Java 8 Native Type

List<Integer> example;
example.add(1);
example.add(2);
example.add(3);
...
example.stream().collect(Collectors.joining(","));

Java 8 Custom Object:

List<Person> person;
...
person.stream().map(Person::getAge).collect(Collectors.joining(","));

T-SQL stored procedure that accepts multiple Id values

A superfast XML Method, if you want to use a stored procedure and pass the comma separated list of Department IDs :

Declare @XMLList xml
SET @XMLList=cast('<i>'+replace(@DepartmentIDs,',','</i><i>')+'</i>' as xml)
SELECT x.i.value('.','varchar(5)') from @XMLList.nodes('i') x(i))

All credit goes to Guru Brad Schulz's Blog

Reading Excel files from C#

Forgive me if I am off-base here, but isn't this what the Office PIA's are for?

How to create a SQL Server function to "join" multiple rows from a subquery into a single delimited field?

Note that Matt's code will result in an extra comma at the end of the string; using COALESCE (or ISNULL for that matter) as shown in the link in Lance's post uses a similar method but doesn't leave you with an extra comma to remove. For the sake of completeness, here's the relevant code from Lance's link on sqlteam.com:

DECLARE @EmployeeList varchar(100)
SELECT @EmployeeList = COALESCE(@EmployeeList + ', ', '') + 
    CAST(EmpUniqueID AS varchar(5))
FROM SalesCallsEmployees
WHERE SalCal_UniqueID = 1

Mac install and open mysql using terminal

  1. install homebrew via terminal

  2. brew install mysql

Unable to install packages in latest version of RStudio and R Version.3.1.1

If you are on Windows, try this:

"C:\Program Files\RStudio\bin\rstudio.exe" http_proxy=http://host:port/

Best way to create unique token in Rails?

Try this way:

As of Ruby 1.9, uuid generation is built-in. Use the SecureRandom.uuid function.
Generating Guids in Ruby

This was helpful for me

Why are primes important in cryptography?

It's not so much the prime numbers themselves that are important, but the algorithms that work with primes. In particular, finding the factors of a number (any number).

As you know, any number has at least two factors. Prime numbers have the unique property in that they have exactly two factors: 1 and themselves.

The reason factoring is so important is mathematicians and computer scientists don't know how to factor a number without simply trying every possible combination. That is, first try dividing by 2, then by 3, then by 4, and so forth. If you try to factor a prime number--especially a very large one--you'll have to try (essentially) every possible number between 2 and that large prime number. Even on the fastest computers, it will take years (even centuries) to factor the kinds of prime numbers used in cryptography.

It is the fact that we don't know how to efficiently factor a large number that gives cryptographic algorithms their strength. If, one day, someone figures out how to do it, all the cryptographic algorithms we currently use will become obsolete. This remains an open area of research.

WordPress Get the Page ID outside the loop

If you're on a page and this does not work:

$page_object = get_queried_object();
$page_id     = get_queried_object_id();

you can try to build the permalink manually with PHP so you can lookup the post ID:

// get or make permalink
$url = !empty(get_the_permalink()) ? get_the_permalink() : (isset($_SERVER['HTTPS']) ? "https" : "http") . "://$_SERVER[HTTP_HOST]$_SERVER[REQUEST_URI]";
$permalink = strtok($url, '?');

// get post_id using url/permalink
$post_id = url_to_postid($url);

// want the post or postmeta? use get_post() or get_post_meta()
$post = get_post($post_id);
$postmeta = get_post_meta($post_id);

It may not catch every possible permalink (especially since I'm stripping out the query string), but you can modify it to fit your use case.

ExecuteNonQuery: Connection property has not been initialized.

just try this..

you need to open the connection using connection.open() on the SqlCommand.Connection object before executing ExecuteNonQuery()

How to remove a newline from a string in Bash

Using bash:

echo "|${COMMAND/$'\n'}|"

(Note that the control character in this question is a 'newline' (\n), not a carriage return (\r); the latter would have output REBOOT| on a single line.)

Explanation

Uses the Bash Shell Parameter Expansion ${parameter/pattern/string}:

The pattern is expanded to produce a pattern just as in filename expansion. Parameter is expanded and the longest match of pattern against its value is replaced with string. [...] If string is null, matches of pattern are deleted and the / following pattern may be omitted.

Also uses the $'' ANSI-C quoting construct to specify a newline as $'\n'. Using a newline directly would work as well, though less pretty:

echo "|${COMMAND/
}|"

Full example

#!/bin/bash
COMMAND="$'\n'REBOOT"
echo "|${COMMAND/$'\n'}|"
# Outputs |REBOOT|

Or, using newlines:

#!/bin/bash
COMMAND="
REBOOT"
echo "|${COMMAND/
}|"
# Outputs |REBOOT|

Python - Join with newline

You forgot to print the result. What you get is the P in RE(P)L and not the actual printed result.

In Py2.x you should so something like

>>> print "\n".join(['I', 'would', 'expect', 'multiple', 'lines'])
I
would
expect
multiple
lines

and in Py3.X, print is a function, so you should do

print("\n".join(['I', 'would', 'expect', 'multiple', 'lines']))

Now that was the short answer. Your Python Interpreter, which is actually a REPL, always displays the representation of the string rather than the actual displayed output. Representation is what you would get with the repr statement

>>> print repr("\n".join(['I', 'would', 'expect', 'multiple', 'lines']))
'I\nwould\nexpect\nmultiple\nlines'

How to call a method in another class in Java?

class A{
  public void methodA(){
    new B().methodB();
    //or
    B.methodB1();
  }
}

class B{
  //instance method
  public void methodB(){
  }
  //static method
  public static  void methodB1(){
  }
}

Javascript - Open a given URL in a new tab by clicking a button

try this

<a id="link" href="www.gmail.com" target="_blank" >gmail</a>

How can I de-install a Perl module installed via `cpan`?

  1. Install App::cpanminus from CPAN (use: cpan App::cpanminus for this).
  2. Type cpanm --uninstall Module::Name (note the "m") to uninstall the module with cpanminus.

This should work.

Numpy ValueError: setting an array element with a sequence. This message may appear without the existing of a sequence?

I believe python arrays just admit values. So convert it to list:

kOUT = np.zeros(N+1)
kOUT = kOUT.tolist()

PyCharm error: 'No Module' when trying to import own module (python script)

Content roots are folders holding your project code while source roots are defined as same too. The only difference i came to understand was that the code in source roots is built before the code in the content root.

Unchecking them wouldn't affect the runtime till the point you're not making separate modules in your package which are manually connected to Django. That means if any of your files do not hold the 'from django import...' or any of the function isn't called via django, unchecking these 2 options will result in a malfunction.

Update - the problem only arises when using Virtual Environmanet, and only when controlling the project via the provided terminal. Cause the terminal still works via the default system pyhtonpath and not the virtual env. while the python django control panel works fine.

Could not load file or assembly CrystalDecisions.ReportAppServer.ClientDoc

It turns out the answer was ridiculously simple, but mystifying as to why it was necessary.

In the IIS Manager on the server, I set the application pool for my web application to not allow 32-bit assemblies.

It seems it assumes, on a 64-bit system, that you must want the 32 bit assembly. Bizarre.

Reusing output from last command in Bash

One way of doing that is by using trap DEBUG:

f() { bash -c "$BASH_COMMAND" >& /tmp/out.log; }
trap 'f' DEBUG

Now most recently executed command's stdout and stderr will be available in /tmp/out.log

Only downside is that it will execute a command twice: once to redirect output and error to /tmp/out.log and once normally. Probably there is some way to prevent this behavior as well.

Ignore mapping one property with Automapper

Could use IgnoreAttribute on the property which needs to be ignored

FPDF utf-8 encoding (HOW-TO)

Not sure if it will do for Greek, but I had the same issue for Brazilian Portuguese characters and my solution was to use html entities. I had basically two cases:

  1. String may contain UTF-8 characters.

For these, I first encoded it to html entities with htmlentities() and then decoded them to iso-8859-1. Example:

$s = html_entity_decode(htmlentities($my_variable_text), ENT_COMPAT | ENT_HTML401, 'iso-8859-1');
  1. Fixed string with html entities:

For these, I just left htmlentities() call out. Example:

$s = html_entity_decode("Treasurer/Tr&eacute;sorier", ENT_COMPAT | ENT_HTML401, 'iso-8859-1');

Then I passed $s to FPDF, like in this example:

$pdf->Cell(100, 20, $s, 0, 0, 'L');

Note: ENT_COMPAT | ENT_HTML401 is the standard value for parameter #2, as in http://php.net/manual/en/function.html-entity-decode.php

Hope that helps.

How can I make a JUnit test wait?

In case your static code analyzer (like SonarQube) complaints, but you can not think of another way, rather than sleep, you may try with a hack like: Awaitility.await().pollDelay(Durations.ONE_SECOND).until(() -> true); It's conceptually incorrect, but it is the same as Thread.sleep(1000).

The best way, of course, is to pass a Callable, with your appropriate condition, rather than true, which I have.

https://github.com/awaitility/awaitility

how to append a css class to an element by javascript?

When an element already has a class name defined, its influence on the element is tied to its position in the string of class names. Later classes override earlier ones, if there is a conflict.

Adding a class to an element ought to move the class name to the sharp end of the list, if it exists already.

document.addClass= function(el, css){
    var tem, C= el.className.split(/\s+/), A=[];    
    while(C.length){
        tem= C.shift();
        if(tem && tem!= css) A[A.length]= tem;
    }
    A[A.length]= css;
    return el.className= A.join(' ');   
}

Using momentjs to convert date to epoch then back to date

http://momentjs.com/docs/#/displaying/unix-timestamp/

You get the number of unix seconds, not milliseconds!

You you need to multiply it with 1000 or using valueOf() and don't forget to use a formatter, since you are using a non ISO 8601 format. And if you forget to pass the formatter, the date will be parsed in the UTC timezone or as an invalid date.

moment("10/15/2014 9:00", "MM/DD/YYYY HH:mm").valueOf()

connecting to phpMyAdmin database with PHP/MySQL

Set up a user, a host the user is allowed to talk to MySQL by using (e.g. localhost), grant that user adequate permissions to do what they need with the database .. and presto.

The user will need basic CRUD privileges to start, that's sufficient to store data received from a form. The rest of the permissions are self explanatory, i.e. permission to alter tables, etc. Give the user no more, no less power than it needs to do its work.

Copy files on Windows Command Line with Progress

The Esentutl /y option allows copyng (single) file files with progress bar like this :

enter image description here

the command should look like :

esentutl /y "FILE.EXT" /d "DEST.EXT" /o

The command is available on every windows machine but the y option is presented in windows vista. As it works only with single files does not look very useful for a small ones. Other limitation is that the command cannot overwrite files. Here's a wrapper script that checks the destination and if needed could delete it (help can be seen by passing /h).

Want to download a Git repository, what do I need (windows machine)?

Install mysysgit. (Same as Greg Hewgill's answer.)

Install Tortoisegit. (Tortoisegit requires mysysgit or something similiar like Cygwin.)

After TortoiseGit is installed, right-click on a folder, select Git Clone..., then enter the Url of the repository, then click Ok.

This answer is not any better than just installing mysysgit, but you can avoid the dreaded command line. :)

How to remove the bottom border of a box with CSS

You could just set the width to auto. Then the width of the div will equal 0 if it has no content.

width:auto;

Request is not available in this context

You can get around the problem without switching to classic mode and still use Application_Start

public class Global : HttpApplication
{
   private static HttpRequest initialRequest;

   static Global()
   {
      initialRequest = HttpContext.Current.Request;       
   }

   void Application_Start(object sender, EventArgs e)
   {
      //access the initial request here
   }

For some reason, the static type is created with a request in its HTTPContext, allowing you to store it and reuse it immediately in the Application_Start event

Commenting code in Notepad++

Yes in Notepad++ you can do that!

Some hotkeys regarding comments:

  • Ctrl+Q Toggle block comment
  • Ctrl+K Block comment
  • Ctrl+Shift+K Block uncomment
  • Ctrl+Shift+Q Stream comment

Source: shortcutworld.com from the Comment / uncomment section.

On the link you will find many other useful shortcuts too.

To switch from vertical split to horizontal split fast in Vim

In VIM, take a look at the following to see different alternatives for what you might have done:

:help opening-window

For instance:

Ctrl-W s
Ctrl-W o
Ctrl-W v
Ctrl-W o
Ctrl-W s
...

jQuery - multiple $(document).ready ...?

All will get executed and On first Called first run basis!!

<div id="target"></div>

<script>
  $(document).ready(function(){
    jQuery('#target').append('target edit 1<br>');
  });
  $(document).ready(function(){
    jQuery('#target').append('target edit 2<br>');
  });
  $(document).ready(function(){
    jQuery('#target').append('target edit 3<br>');
  });
</script>

Demo As you can see they do not replace each other

Also one thing i would like to mention

in place of this

$(document).ready(function(){});

you can use this shortcut

jQuery(function(){
   //dom ready codes
});

Git pull command from different user

Was looking for the solution of a similar problem. Thanks to the answer provided by Davlet and Cupcake I was able to solve my problem.

Posting this answer here since I think this is the intended question

So I guess generally the problem that people like me face is what to do when a repo is cloned by another user on a server and that user is no longer associated with the repo.

How to pull from the repo without using the credentials of the old user ?

You edit the .git/config file of your repo.

and change

url = https://<old-username>@github.com/abc/repo.git/

to

url = https://<new-username>@github.com/abc/repo.git/

After saving the changes, from now onwards git pull will pull data while using credentials of the new user.

I hope this helps anyone with a similar problem

What's the fastest way of checking if a point is inside a polygon in python

Comparison of different methods

I found other methods to check if a point is inside a polygon (here). I tested two of them only (is_inside_sm and is_inside_postgis) and the results were the same as the other methods.

Thanks to @epifanio, I parallelized the codes and compared them with @epifanio and @user3274748 (ray_tracing_numpy) methods. Note that both methods had a bug so I fixed them as shown in their codes below.

One more thing that I found is that the code provided for creating a polygon does not generate a closed path np.linspace(0,2*np.pi,lenpoly)[:-1]. As a result, the codes provided in above GitHub repository may not work properly. So It's better to create a closed path (first and last points should be the same).

Codes

Method 1: parallelpointinpolygon

from numba import jit, njit
import numba
import numpy as np 

@jit(nopython=True)
def pointinpolygon(x,y,poly):
    n = len(poly)
    inside = False
    p2x = 0.0
    p2y = 0.0
    xints = 0.0
    p1x,p1y = poly[0]
    for i in numba.prange(n+1):
        p2x,p2y = poly[i % n]
        if y > min(p1y,p2y):
            if y <= max(p1y,p2y):
                if x <= max(p1x,p2x):
                    if p1y != p2y:
                        xints = (y-p1y)*(p2x-p1x)/(p2y-p1y)+p1x
                    if p1x == p2x or x <= xints:
                        inside = not inside
        p1x,p1y = p2x,p2y

    return inside


@njit(parallel=True)
def parallelpointinpolygon(points, polygon):
    D = np.empty(len(points), dtype=numba.boolean) 
    for i in numba.prange(0, len(D)):   #<-- Fixed here, must start from zero
        D[i] = pointinpolygon(points[i,0], points[i,1], polygon)
    return D  

Method 2: ray_tracing_numpy_numba

@jit(nopython=True)
def ray_tracing_numpy_numba(points,poly):
    x,y = points[:,0], points[:,1]
    n = len(poly)
    inside = np.zeros(len(x),np.bool_)
    p2x = 0.0
    p2y = 0.0
    p1x,p1y = poly[0]
    for i in range(n+1):
        p2x,p2y = poly[i % n]
        idx = np.nonzero((y > min(p1y,p2y)) & (y <= max(p1y,p2y)) & (x <= max(p1x,p2x)))[0]
        if len(idx):    # <-- Fixed here. If idx is null skip comparisons below.
            if p1y != p2y:
                xints = (y[idx]-p1y)*(p2x-p1x)/(p2y-p1y)+p1x
            if p1x == p2x:
                inside[idx] = ~inside[idx]
            else:
                idxx = idx[x[idx] <= xints]
                inside[idxx] = ~inside[idxx]    

        p1x,p1y = p2x,p2y
    return inside 

Method 3: Matplotlib contains_points

path = mpltPath.Path(polygon,closed=True)  # <-- Very important to mention that the path 
                                           #     is closed (default is false)

Method 4: is_inside_sm (got it from here)

@jit(nopython=True)
def is_inside_sm(polygon, point):
    length = len(polygon)-1
    dy2 = point[1] - polygon[0][1]
    intersections = 0
    ii = 0
    jj = 1

    while ii<length:
        dy  = dy2
        dy2 = point[1] - polygon[jj][1]

        # consider only lines which are not completely above/bellow/right from the point
        if dy*dy2 <= 0.0 and (point[0] >= polygon[ii][0] or point[0] >= polygon[jj][0]):

            # non-horizontal line
            if dy<0 or dy2<0:
                F = dy*(polygon[jj][0] - polygon[ii][0])/(dy-dy2) + polygon[ii][0]

                if point[0] > F: # if line is left from the point - the ray moving towards left, will intersect it
                    intersections += 1
                elif point[0] == F: # point on line
                    return 2

            # point on upper peak (dy2=dx2=0) or horizontal line (dy=dy2=0 and dx*dx2<=0)
            elif dy2==0 and (point[0]==polygon[jj][0] or (dy==0 and (point[0]-polygon[ii][0])*(point[0]-polygon[jj][0])<=0)):
                return 2

        ii = jj
        jj += 1

    #print 'intersections =', intersections
    return intersections & 1  


@njit(parallel=True)
def is_inside_sm_parallel(points, polygon):
    ln = len(points)
    D = np.empty(ln, dtype=numba.boolean) 
    for i in numba.prange(ln):
        D[i] = is_inside_sm(polygon,points[i])
    return D  

Method 5: is_inside_postgis (got it from here)

@jit(nopython=True)
def is_inside_postgis(polygon, point):
    length = len(polygon)
    intersections = 0

    dx2 = point[0] - polygon[0][0]
    dy2 = point[1] - polygon[0][1]
    ii = 0
    jj = 1

    while jj<length:
        dx  = dx2
        dy  = dy2
        dx2 = point[0] - polygon[jj][0]
        dy2 = point[1] - polygon[jj][1]

        F =(dx-dx2)*dy - dx*(dy-dy2);
        if 0.0==F and dx*dx2<=0 and dy*dy2<=0:
            return 2;

        if (dy>=0 and dy2<0) or (dy2>=0 and dy<0):
            if F > 0:
                intersections += 1
            elif F < 0:
                intersections -= 1

        ii = jj
        jj += 1

    #print 'intersections =', intersections
    return intersections != 0  


@njit(parallel=True)
def is_inside_postgis_parallel(points, polygon):
    ln = len(points)
    D = np.empty(ln, dtype=numba.boolean) 
    for i in numba.prange(ln):
        D[i] = is_inside_postgis(polygon,points[i])
    return D  

Benchmark

enter image description here

Timing for 10 million points:

parallelpointinpolygon Elapsed time:      4.0122294425964355
Matplotlib contains_points Elapsed time: 14.117807388305664
ray_tracing_numpy_numba Elapsed time:     7.908452272415161
sm_parallel Elapsed time:                 0.7710440158843994
is_inside_postgis_parallel Elapsed time:  2.131121873855591

Here is the code.

import matplotlib.pyplot as plt
import matplotlib.path as mpltPath
from time import time
import numpy as np

np.random.seed(2)

time_parallelpointinpolygon=[]
time_mpltPath=[]
time_ray_tracing_numpy_numba=[]
time_is_inside_sm_parallel=[]
time_is_inside_postgis_parallel=[]
n_points=[]

for i in range(1, 10000002, 1000000): 
    n_points.append(i)
    
    lenpoly = 100
    polygon = [[np.sin(x)+0.5,np.cos(x)+0.5] for x in np.linspace(0,2*np.pi,lenpoly)]
    polygon = np.array(polygon)
    N = i
    points = np.random.uniform(-1.5, 1.5, size=(N, 2))
    
    
    #Method 1
    start_time = time()
    inside1=parallelpointinpolygon(points, polygon)
    time_parallelpointinpolygon.append(time()-start_time)

    # Method 2
    start_time = time()
    path = mpltPath.Path(polygon,closed=True)
    inside2 = path.contains_points(points)
    time_mpltPath.append(time()-start_time)

    # Method 3
    start_time = time()
    inside3=ray_tracing_numpy_numba(points,polygon)
    time_ray_tracing_numpy_numba.append(time()-start_time)

    # Method 4
    start_time = time()
    inside4=is_inside_sm_parallel(points,polygon)
    time_is_inside_sm_parallel.append(time()-start_time)

    # Method 5
    start_time = time()
    inside5=is_inside_postgis_parallel(points,polygon)
    time_is_inside_postgis_parallel.append(time()-start_time)


    
plt.plot(n_points,time_parallelpointinpolygon,label='parallelpointinpolygon')
plt.plot(n_points,time_mpltPath,label='mpltPath')
plt.plot(n_points,time_ray_tracing_numpy_numba,label='ray_tracing_numpy_numba')
plt.plot(n_points,time_is_inside_sm_parallel,label='is_inside_sm_parallel')
plt.plot(n_points,time_is_inside_postgis_parallel,label='is_inside_postgis_parallel')
plt.xlabel("N points")
plt.ylabel("time (sec)")
plt.legend(loc = 'best')
plt.show()

CONCLUSION

The fastest algorithms are:

1- is_inside_sm_parallel

2- is_inside_postgis_parallel

3- parallelpointinpolygon (@epifanio)

JavaScript Promises - reject vs. throw

There's one difference — which shouldn't matter — that the other answers haven't touched on, so:

There's no difference that's likely to matter, no. Yes, there is a very small difference.

If the fulfillment handler passed to then throws, the promise returned by that call to then is rejected with what was thrown.

If it returns a rejected promise, the promise returned by the call to then is resolved to that promise (and will ultimately be rejected, since the promise it's resolved to is rejected), which may introduce one extra async "tick" (one more loop in the microtask queue, to put it in browser terms).

Any code that relies on that difference is fundamentally broken, though. :-) It shouldn't be that sensitive to the timing of the promise settlement.

Here's an example:

_x000D_
_x000D_
function usingThrow(val) {
    return Promise.resolve(val)
        .then(v => {
            if (v !== 42) {
                throw new Error(`${v} is not 42!`);
            }
            return v;
        });
}
function usingReject(val) {
    return Promise.resolve(val)
        .then(v => {
            if (v !== 42) {
                return Promise.reject(new Error(`${v} is not 42!`));
            }
            return v;
        });
}

// The rejection handler on this chain may be called **after** the
// rejection handler on the following chain
usingReject(1)
.then(v => console.log(v))
.catch(e => console.error("Error from usingReject:", e.message));

// The rejection handler on this chain may be called **before** the
// rejection handler on the preceding chain
usingThrow(2)
.then(v => console.log(v))
.catch(e => console.error("Error from usingThrow:", e.message));
_x000D_
_x000D_
_x000D_

If you run that, as of this writing you get:

Error from usingThrow: 2 is not 42!
Error from usingReject: 1 is not 42!

Note the order.

Compare that to the same chains but both using usingThrow:

_x000D_
_x000D_
function usingThrow(val) {
    return Promise.resolve(val)
        .then(v => {
            if (v !== 42) {
                throw new Error(`${v} is not 42!`);
            }
            return v;
        });
}

usingThrow(1)
.then(v => console.log(v))
.catch(e => console.error("Error from usingThrow:", e.message));

usingThrow(2)
.then(v => console.log(v))
.catch(e => console.error("Error from usingThrow:", e.message));
_x000D_
_x000D_
_x000D_

which shows that the rejection handlers ran in the other order:

Error from usingThrow: 1 is not 42!
Error from usingThrow: 2 is not 42!

I said "may" above because there's been some work in other areas that removed this unnecessary extra tick in other similar situations if all of the promises involved are native promises (not just thenables). (Specifically: In an async function, return await x originally introduced an extra async tick vs. return x while being otherwise identical; ES2020 changed it so that if x is a native promise, the extra tick is removed.)

Again, any code that's that sensitive to the timing of the settlement of a promise is already broken. So really it doesn't/shouldn't matter.

In practical terms, as other answers have mentioned:

  • As Kevin B pointed out, throw won't work if you're in a callback to some other function you've used within your fulfillment handler — this is the biggie
  • As lukyer pointed out, throw abruptly terminates the function, which can be useful (but you're using return in your example, which does the same thing)
  • As Vencator pointed out, you can't use throw in a conditional expression (? :), at least not for now

Other than that, it's mostly a matter of style/preference, so as with most of those, agree with your team what you'll do (or that you don't care either way), and be consistent.

Auto-click button element on page load using jQuery

We should rather use Javascript.

    <button href="images/car.jpg" id="myButton">
        Here is the Button to be clicked
    </button>


    <script>

        $(document).ready(function(){
            document.getElementById("myButton").click();
        });

    </script>

Should I call Close() or Dispose() for stream objects?

For what it's worth, the source code for Stream.Close explains why there are two methods:

// Stream used to require that all cleanup logic went into Close(),
// which was thought up before we invented IDisposable.  However, we
// need to follow the IDisposable pattern so that users can write
// sensible subclasses without needing to inspect all their base
// classes, and without worrying about version brittleness, from a
// base class switching to the Dispose pattern.  We're moving
// Stream to the Dispose(bool) pattern - that's where all subclasses
// should put their cleanup now.

In short, Close is only there because it predates Dispose, and it can't be deleted for compatibility reasons.

How to Sign an Already Compiled Apk

create a key using

keytool -genkey -v -keystore my-release-key.keystore -alias alias_name -keyalg RSA -keysize 2048 -validity 10000

then sign the apk using :

jarsigner -verbose -sigalg SHA1withRSA -digestalg SHA1 -keystore my-release-key.keystore my_application.apk alias_name

check here for more info

Styling an input type="file" button

If anyone still cares on how to do this without JavaScript, let me complete Josh answer:

How to display the text of the filename:

The easiest way is to set both elements to a position:relative, give the label a higher z-index and give the input file negative margin until the label text is where you want it to be. Do not use display:none on the input!

Example:

input[type="file"] {
  position:relative;
  z-index:1;
  margin-left:-90px;
}

.custom-file-upload {
  border: 1px solid #ccc;
  display: inline-block;
  padding: 6px 12px;
  cursor: pointer;
  position:relative;
  z-index:2;
  background:white;

}

Difference between setUp() and setUpBeforeClass()

The @BeforeClass and @AfterClass annotated methods will be run exactly once during your test run - at the very beginning and end of the test as a whole, before anything else is run. In fact, they're run before the test class is even constructed, which is why they must be declared static.

The @Before and @After methods will be run before and after every test case, so will probably be run multiple times during a test run.

So let's assume you had three tests in your class, the order of method calls would be:

setUpBeforeClass()

  (Test class first instance constructed and the following methods called on it)
    setUp()
    test1()
    tearDown()

  (Test class second instance constructed and the following methods called on it)
    setUp()
    test2()
    tearDown()

  (Test class third instance constructed and the following methods called on it)
    setUp()
    test3()
    tearDown()

tearDownAfterClass()

Get client IP address via third party web service

Checking your linked site, you may include a script tag passing a ?var=desiredVarName parameter which will be set as a global variable containing the IP address:

<script type="text/javascript" src="http://l2.io/ip.js?var=myip"></script>
                                                      <!-- ^^^^ -->
<script>alert(myip);</script>

Demo

I believe I don't have to say that this can be easily spoofed (through either use of proxies or spoofed request headers), but it is worth noting in any case.


HTTPS support

In case your page is served using the https protocol, most browsers will block content in the same page served using the http protocol (that includes scripts and images), so the options are rather limited. If you have < 5k hits/day, the Smart IP API can be used. For instance:

<script>
var myip;
function ip_callback(o) {
    myip = o.host;
}
</script>
<script src="https://smart-ip.net/geoip-json?callback=ip_callback"></script>
<script>alert(myip);</script>

Demo

Edit: Apparently, this https service's certificate has expired so the user would have to add an exception manually. Open its API directly to check the certificate state: https://smart-ip.net/geoip-json


With back-end logic

The most resilient and simple way, in case you have back-end server logic, would be to simply output the requester's IP inside a <script> tag, this way you don't need to rely on external resources. For example:

PHP:

<script>var myip = '<?php echo $_SERVER['REMOTE_ADDR']; ?>';</script>

There's also a more sturdy PHP solution (accounting for headers that are sometimes set by proxies) in this related answer.

C#:

<script>var myip = '<%= Request.UserHostAddress %>';</script>

How to transform numpy.matrix or array to scipy sparse matrix

As for the inverse, the function is inv(A), but I won't recommend using it, since for huge matrices it is very computationally costly and unstable. Instead, you should use an approximation to the inverse, or if you want to solve Ax = b you don't really need A-1.

PHP Redirect to another page after form submit

Whenever you want to redirect, send the headers:

header("Location: http://www.example.com/");

Remember you cant send data to the client before that, though.

How to prevent the "Confirm Form Resubmission" dialog?

I was having this problem and added this JavaScript to the bottom of my page (read it at https://www.webtrickshome.com/faq/how-to-stop-form-resubmission-on-page-refresh) and it seemed to work. It seems much simpler a solution. Any drawbacks?

<script>
if ( window.history.replaceState ) {
  window.history.replaceState( null, null, window.location.href );
}
</script>

Thanks,

doug

Difference between DataFrame, Dataset, and RDD in Spark

A DataFrame is defined well with a google search for "DataFrame definition":

A data frame is a table, or two-dimensional array-like structure, in which each column contains measurements on one variable, and each row contains one case.

So, a DataFrame has additional metadata due to its tabular format, which allows Spark to run certain optimizations on the finalized query.

An RDD, on the other hand, is merely a Resilient Distributed Dataset that is more of a blackbox of data that cannot be optimized as the operations that can be performed against it, are not as constrained.

However, you can go from a DataFrame to an RDD via its rdd method, and you can go from an RDD to a DataFrame (if the RDD is in a tabular format) via the toDF method

In general it is recommended to use a DataFrame where possible due to the built in query optimization.

Create a file from a ByteArrayOutputStream

You can use a FileOutputStream for this.

FileOutputStream fos = null;
try {
    fos = new FileOutputStream(new File("myFile")); 
    ByteArrayOutputStream baos = new ByteArrayOutputStream();

    // Put data in your baos

    baos.writeTo(fos);
} catch(IOException ioe) {
    // Handle exception here
    ioe.printStackTrace();
} finally {
    fos.close();
}

How to open a new HTML page using jQuery?

If you want to use jQuery, the .load() function is the correct function you are after;

But you are missing the # from the div1 id selector in the example 2)

This should work:

$("#div1").load("file2.html");

How to pass extra variables in URL with WordPress

add following code in function.php

add_filter( 'query_vars', 'addnew_query_vars', 10, 1 );
function addnew_query_vars($vars)
{   
    $vars[] = 'var1'; // var1 is the name of variable you want to add       
    return $vars;
}

then you will b able to use $_GET['var1']

Create Directory if it doesn't exist with Ruby

Another simple way:

Dir.mkdir('tmp/excel') unless Dir.exist?('tmp/excel')

Python Pandas : pivot table with aggfunc = count unique distinct

This is a good way of counting entries within .pivot_table:

df2.pivot_table(values='X', index=['Y','Z'], columns='X', aggfunc='count')


        X1  X2
Y   Z       
Y1  Z1   1   1
    Z2   1  NaN
Y2  Z3   1  NaN

How to print multiple variable lines in Java

You can do it with 1 printf:

System.out.printf("First Name: %s\nLast Name: %s",firstname, lastname);

How to draw interactive Polyline on route google maps v2 android

You should use options.addAll(allPoints); instead of options.add(point);

Delete all SYSTEM V shared memory and semaphores on UNIX-like systems

Since you mentioned that you're working on a NFS system, do you have access to those semaphores and shared memory? I think you misunderstood what they are, they are an API code that enables processes to communicate with each other, semaphores are a solution for preventing race conditions and for threads to communicate with each other, in simple answer, they do not leave any residue on any filesystem.

Unless you are using an socket or a pipe? Do you have the necessary permissions to remove them, why are they on an NFS system?

Hope this helps, Best regards, Tom.

Oracle "ORA-01008: not all variables bound" Error w/ Parameters

The ODP.Net provider from oracle uses bind by position as default. To change the behavior to bind by name. Set property BindByName to true. Than you can dismiss the double definition of parameters.

using(OracleCommand cmd = con.CreateCommand()) {
    ...
    cmd.BindByName = true;
    ...
}

How to use OrderBy with findAll in Spring Data

I try in this example to show you a complete example to personalize your OrderBy sorts

 import java.util.List;
 import org.springframework.data.domain.Page;
 import org.springframework.data.domain.Sort;
 import org.springframework.data.jpa.repository.*;
 import org.springframework.data.repository.query.Param;
 import org.springframework.stereotype.Repository;
 import org.springframework.data.domain.Sort;
 /**
 * Spring Data  repository for the User entity.
 */
 @SuppressWarnings("unused")
 @Repository
 public interface UserRepository extends JpaRepository<User, Long> {
 List <User> findAllWithCustomOrderBy(Sort sort);
 }

you will use this example : A method for build dynamically a object that instance of Sort :

import org.springframework.data.domain.Sort;
public class SampleOrderBySpring{
 Sort dynamicOrderBySort = createSort();
     public static void main( String[] args )
     {
       System.out.println("default sort \"firstName\",\"name\",\"age\",\"size\" ");
       Sort defaultSort = createStaticSort();
       System.out.println(userRepository.findAllWithCustomOrderBy(defaultSort ));


       String[] orderBySortedArray = {"name", "firstName"};
       System.out.println("default sort ,\"name\",\"firstName\" ");
       Sort dynamicSort = createDynamicSort(orderBySortedArray );
       System.out.println(userRepository.findAllWithCustomOrderBy(dynamicSort ));
      }
      public Sort createDynamicSort(String[] arrayOrdre) {
        return  Sort.by(arrayOrdre);
        }

   public Sort createStaticSort() {
        String[] arrayOrdre  ={"firstName","name","age","size");
        return  Sort.by(arrayOrdre);
        }
}

How can I do division with variables in a Linux shell?

To get the numbers after decimal point, you can do this:-

read num1 num2
div=`echo $num1 / $num2 | bc -l`
echo $div

repaint() in Java

You're doing things in the wrong order.

You need to first add all JComponents to the JFrame, and only then call pack() and then setVisible(true) on the JFrame

If you later added JComponents that could change the GUI's size you will need to call pack() again, and then repaint() on the JFrame after doing so.

How do I read the source code of shell commands?

    cd ~ && apt-get source coreutils && ls -d coreutils*     

You should be able to use a command like this on ubuntu to gather the source for a package, you can omit sudo assuming your downloading to a location you own.

Using $_POST to get select option value from HTML


-- html file --

<select name='city[]'> 
                <option name='Kabul' value="Kabul" > Kabul </option>
                <option name='Herat' value='Herat' selected="selected">             Herat </option>
                <option name='Mazar' value='Mazar'>Mazar </option>
</select>

-- php file --

$city = (isset($_POST['city']) ? $_POST['city']: null);
print("city is: ".$city[0]);

Make absolute positioned div expand parent div height

You answered the question by yourself: "I know that absolute positioned elements are removed from the flow, thus ignored by other elements." So you can't set the parents height according to an absolutely positioned element.

You either use fixed heights or you need to involve JS.

What is difference between sjlj vs dwarf vs seh?

There's a short overview at MinGW-w64 Wiki:

Why doesn't mingw-w64 gcc support Dwarf-2 Exception Handling?

The Dwarf-2 EH implementation for Windows is not designed at all to work under 64-bit Windows applications. In win32 mode, the exception unwind handler cannot propagate through non-dw2 aware code, this means that any exception going through any non-dw2 aware "foreign frames" code will fail, including Windows system DLLs and DLLs built with Visual Studio. Dwarf-2 unwinding code in gcc inspects the x86 unwinding assembly and is unable to proceed without other dwarf-2 unwind information.

The SetJump LongJump method of exception handling works for most cases on both win32 and win64, except for general protection faults. Structured exception handling support in gcc is being developed to overcome the weaknesses of dw2 and sjlj. On win64, the unwind-information are placed in xdata-section and there is the .pdata (function descriptor table) instead of the stack. For win32, the chain of handlers are on stack and need to be saved/restored by real executed code.

GCC GNU about Exception Handling:

GCC supports two methods for exception handling (EH):

  • DWARF-2 (DW2) EH, which requires the use of DWARF-2 (or DWARF-3) debugging information. DW-2 EH can cause executables to be slightly bloated because large call stack unwinding tables have to be included in th executables.
  • A method based on setjmp/longjmp (SJLJ). SJLJ-based EH is much slower than DW2 EH (penalising even normal execution when no exceptions are thrown), but can work across code that has not been compiled with GCC or that does not have call-stack unwinding information.

[...]

Structured Exception Handling (SEH)

Windows uses its own exception handling mechanism known as Structured Exception Handling (SEH). [...] Unfortunately, GCC does not support SEH yet. [...]

See also:

Find out time it took for a python script to complete execution

Use the timeit module. It's very easy. Run your example.py file so it is active in the Python Shell, you should now be able to call your function in the shell. Try it out to check it works

>>>fun(input)
output

Good, that works, now import timeit and set up a timer

>>>import timeit
>>>t = timeit.Timer('example.fun(input)','import example')
>>>

Now we have our timer set up we can see how long it takes

>>>t.timeit(number=1)
some number here

And there we go, it will tell you how many seconds (or less) it took to execute that function. If it's a simple function then you can increase it to t.timeit(number=1000) (or any number!) and then divide the answer by the number to get the average.

I hope this helps.

How can I check if a View exists in a Database?

This is the most portable, least intrusive way:

select
    count(*)
from
    INFORMATION_SCHEMA.VIEWS
where
    table_name = 'MyView'
    and table_schema = 'MySchema'

Edit: This does work on SQL Server, and it doesn't require you joining to sys.schemas to get the schema of the view. This is less important if everything is dbo, but if you're making good use of schemas, then you should keep that in mind.

Each RDBMS has their own little way of checking metadata like this, but information_schema is actually ANSI, and I think Oracle and apparently SQLite are the only ones that don't support it in some fashion.

Changing git commit message after push (given that no one pulled from remote)

To edit a commit other than the most recent:

Step1: git rebase -i HEAD~n to do interactive rebase for the last n commits affected. (i.e. if you want to change a commit message 3 commits back, do git rebase -i HEAD~3)

git will pop up an editor to handle those commits, notice this command:

#  r, reword = use commit, but edit the commit message

that is exactly we need!

Step2: Change pick to r for those commits that you want to update the message. Don't bother changing the commit message here, it will be ignored. You'll do that on the next step. Save and close the editor.

Note that if you edit your rebase 'plan' yet it doesn't begin the process of letting you rename the files, run:

git rebase --continue

If you want to change the text editor used for the interactive session (e.g. from the default vi to nano), run:

GIT_EDITOR=nano git rebase -i HEAD~n

Step3: Git will pop up another editor for every revision you put r before. Update the commit msg as you like, then save and close the editor.

Step4: After all commits msgs are updated. you might want to do git push -f to update the remote.

What does java.lang.Thread.interrupt() do?

Thread interruption is based on flag interrupt status. For every thread default value of interrupt status is set to false. Whenever interrupt() method is called on thread, interrupt status is set to true.

  1. If interrupt status = true (interrupt() already called on thread), that particular thread cannot go to sleep. If sleep is called on that thread interrupted exception is thrown. After throwing exception again flag is set to false.
  2. If thread is already sleeping and interrupt() is called, thread will come out of sleeping state and throw interrupted Exception.

Simple working Example of json.net in VB.net

Your class JSON_result does not match your JSON string. Note how the object JSON_result is going to represent is wrapped in another property named "Venue".

So either create a class for that, e.g.:

Public Class Container
    Public Venue As JSON_result
End Class

Public Class JSON_result
    Public ID As Integer
    Public Name As String
    Public NameWithTown As String
    Public NameWithDestination As String
    Public ListingType As String
End Class

Dim obj = JsonConvert.DeserializeObject(Of Container)(...your_json...)

or change your JSON string to

{
    "ID": 3145,
    "Name": "Big Venue, Clapton",
    "NameWithTown": "Big Venue, Clapton, London",
    "NameWithDestination": "Big Venue, Clapton, London",
    "ListingType": "A",
    "Address": {
        "Address1": "Clapton Raod",
        "Address2": "",
        "Town": "Clapton",
        "County": "Greater London",
        "Postcode": "PO1 1ST",
        "Country": "United Kingdom",
        "Region": "Europe"
    },
    "ResponseStatus": {
        "ErrorCode": "200",
        "Message": "OK"
    }
}

or use e.g. a ContractResolver to parse the JSON string.

HTML form with side by side input fields

You could use the {display: inline-flex;} this would produce this: inline-flex

How can I store the result of a system command in a Perl variable?

The easiest way is to use the `` feature in Perl. This will execute what is inside and return what was printed to stdout:

 my $pid = 5892;
 my $var = `top -H -p $pid -n 1 | grep myprocess | wc -l`;
 print "not = $var\n";

This should do it.

File Upload In Angular?

In the simplest form, the following code works in Angular 6/7

this.http.post("http://destinationurl.com/endpoint", fileFormData)
  .subscribe(response => {
    //handle response
  }, err => {
    //handle error
  });

Here is the complete implementation

What is the difference between C and embedded C?

In the C standard, a standalone implementation doesn't have to provide all of the library functions that a hosted implementation has to provide. The C standard doesn't care about embedded, but vendors of embedded systems usually provide standalone implementations with whatever amount of libraries they're willing to provide.

C is a widely used general purpose high level programming language mainly intended for system programming.

Embedded C is an extension to C programming language that provides support for developing efficient programs for embedded devices.It is not a part of the C language

You can also refer to the articles below:

how to change a selections options based on another select option selected?

you can use data-tag in html5 and do this using this code:

_x000D_
_x000D_
<script>_x000D_
 $('#mainCat').on('change', function() {_x000D_
  var selected = $(this).val();_x000D_
  $("#expertCat option").each(function(item){_x000D_
   console.log(selected) ;  _x000D_
   var element =  $(this) ; _x000D_
   console.log(element.data("tag")) ; _x000D_
   if (element.data("tag") != selected){_x000D_
    element.hide() ; _x000D_
   }else{_x000D_
    element.show();_x000D_
   }_x000D_
  }) ; _x000D_
  _x000D_
  $("#expertCat").val($("#expertCat option:visible:first").val());_x000D_
  _x000D_
});_x000D_
</script>
_x000D_
<script src="https://ajax.googleapis.com/ajax/libs/jquery/1.11.3/jquery.min.js"></script>_x000D_
<select id="mainCat">_x000D_
   <option value = '1'>navid</option>_x000D_
   <option value = '2'>javad</option>_x000D_
   <option value = '3'>mamal</option>_x000D_
  </select>_x000D_
  _x000D_
  <select id="expertCat">_x000D_
   <option  value = '1' data-tag='2'>UI</option>_x000D_
   <option  value = '2' data-tag='2'>Java Android</option>_x000D_
   <option  value = '3' data-tag='1'>Web</option>_x000D_
   <option  value = '3' data-tag='1'>Server</option>_x000D_
   <option  value = '3' data-tag='3'>Back End</option>_x000D_
   <option  value = '3' data-tag='3'>.net</option>_x000D_
  </select>
_x000D_
_x000D_
_x000D_

geom_smooth() what are the methods available?

The se argument from the example also isn't in the help or online documentation.

When 'se' in geom_smooth is set 'FALSE', the error shading region is not visible

How to remove ASP.Net MVC Default HTTP Headers?

You can also remove them by adding code to your global.asax file:

 protected void Application_PreSendRequestHeaders(object sender, EventArgs e)
 {
   HttpContext.Current.Response.Headers.Remove("X-Powered-By");
   HttpContext.Current.Response.Headers.Remove("X-AspNet-Version");
   HttpContext.Current.Response.Headers.Remove("X-AspNetMvc-Version");
   HttpContext.Current.Response.Headers.Remove("Server");
 }

Most efficient way to see if an ArrayList contains an object in Java

If you are a user of my ForEach DSL, it can be done with a Detect query.

Foo foo = ...
Detect<Foo> query = Detect.from(list);
for (Detect<Foo> each: query) 
    each.yield = each.element.a == foo.a && each.element.b == foo.b;
return query.result();

How do you install Boost on MacOS?

Try +universal

One thing to note: in order for that to make a difference you need to have built python with +universal, if you haven't or you're not sure you can just rebuild python +universal. This applies to both brew as well as macports.

$ brew reinstall python
$ brew install boost

OR

$ sudo port -f uninstall python
$ sudo port install python +universal
$ sudo port install boost +universal

How to recognize vehicle license / number plate (ANPR) from an image?

Yes I use gocr at http://jocr.sourceforge.net/ its a commandline application which you could execute from your application. I use it in a couple of my applications.

Retrieving the last record in each group - MySQL

Use your subquery to return the correct grouping, because you're halfway there.

Try this:

select
    a.*
from
    messages a
    inner join 
        (select name, max(id) as maxid from messages group by name) as b on
        a.id = b.maxid

If it's not id you want the max of:

select
    a.*
from
    messages a
    inner join 
        (select name, max(other_col) as other_col 
         from messages group by name) as b on
        a.name = b.name
        and a.other_col = b.other_col

This way, you avoid correlated subqueries and/or ordering in your subqueries, which tend to be very slow/inefficient.

How do I run a terminal inside of Vim?

I know that I'm not directly answering the question, but I think it's a good approach. Nobody has mentioned tmux (or at least not as a standalone answer). Tmux is a terminal multiplexor like screen. Most stuff can be made in both multiplexors, but afaik tmux it's more easily to configure. Also tmux right now is being more actively developed than screen and there's quite a big ecosystem around it, like tools that help the configuration, ecc.

Also for vim, there's another plugin: ViMUX, that helps a lot in the interaction between both tools. You can call commands with:

:call VimuxRunCommand("ls")

That command creates a small horizontal split below the current pane vim is in.

It can also let you run from a prompt in case you don't want to run the whole command:

<Leader>vp :VimuxPromptCommand<CR>

As it weren't enought, there are at least 6 'platform specific plugins':

Here is a nice "use case": Tests on demand using Vimux and Turbux with Spork and Guard

Check if an object belongs to a class in Java

If you ever need to do this dynamically, you can use the following:

boolean isInstance(Object object, Class<?> type) {
    return type.isInstance(object);
}

You can get an instance of java.lang.Class by calling the instance method Object::getClass on any object (returns the Class which that object is an instance of), or you can do class literals (for example, String.class, List.class, int[].class). There are other ways as well, through the reflection API (which Class itself is the entry point for).

What is the recommended way to make a numeric TextField in JavaFX?

I know this is a rather old thread, but for future readers here is another solution I found quite intuitive:

public class NumberTextField extends TextField
{

    @Override
    public void replaceText(int start, int end, String text)
    {
        if (validate(text))
        {
            super.replaceText(start, end, text);
        }
    }

    @Override
    public void replaceSelection(String text)
    {
        if (validate(text))
        {
            super.replaceSelection(text);
        }
    }

    private boolean validate(String text)
    {
        return text.matches("[0-9]*");
    }
}

Edit: Thanks none_ and SCBoy for your suggested improvements.

Linux: is there a read or recv from socket with timeout?

LINUX

struct timeval tv;
tv.tv_sec = 30;        // 30 Secs Timeout
tv.tv_usec = 0;        // Not init'ing this can cause strange errors
setsockopt(sockfd, SOL_SOCKET, SO_RCVTIMEO, (const char*)&tv,sizeof(struct timeval));

WINDOWS

DWORD timeout = SOCKET_READ_TIMEOUT_SEC * 1000;
setsockopt(socket, SOL_SOCKET, SO_RCVTIMEO, (const char*)&timeout, sizeof(timeout));

NOTE: You have put this setting before bind() function call for proper run

Using Spring RestTemplate in generic method with generic parameter

I am using org.springframework.core.ResolvableType for a ListResultEntity :

    ResolvableType resolvableType = ResolvableType.forClassWithGenerics(ListResultEntity.class, itemClass);
    ParameterizedTypeReference<ListResultEntity<T>> typeRef = ParameterizedTypeReference.forType(resolvableType.getType());

So in your case:

public <T> ResponseWrapper<T> makeRequest(URI uri, Class<T> clazz) {
   ResponseEntity<ResponseWrapper<T>> response = template.exchange(
        uri,
        HttpMethod.POST,
        null,
        ParameterizedTypeReference.forType(ResolvableType.forClassWithGenerics(ResponseWrapper.class, clazz)));
    return response;
}

This only makes use of spring and of course requires some knowledge about the returned types (but should even work for things like Wrapper>> as long as you provide the classes as varargs )

c++ compile error: ISO C++ forbids comparison between pointer and integer

"y" is a string/array/pointer. 'y' is a char/integral type

How to install MinGW-w64 and MSYS2?

Unfortunately, the MinGW-w64 installer you used sometimes has this issue. I myself am not sure about why this happens (I think it has something to do with Sourceforge URL redirection or whatever that the installer currently can't handle properly enough).

Anyways, if you're already planning on using MSYS2, there's no need for that installer.

  1. Download MSYS2 from this page (choose 32 or 64-bit according to what version of Windows you are going to use it on, not what kind of executables you want to build, both versions can build both 32 and 64-bit binaries).

  2. After the install completes, click on the newly created "MSYS2 Shell" option under either MSYS2 64-bit or MSYS2 32-bit in the Start menu. Update MSYS2 according to the wiki (although I just do a pacman -Syu, ignore all errors and close the window and open a new one, this is not recommended and you should do what the wiki page says).

  3. Install a toolchain

    a) for 32-bit:

    pacman -S mingw-w64-i686-gcc
    

    b) for 64-bit:

    pacman -S mingw-w64-x86_64-gcc
    
  4. install any libraries/tools you may need. You can search the repositories by doing

    pacman -Ss name_of_something_i_want_to_install
    

    e.g.

    pacman -Ss gsl
    

    and install using

    pacman -S package_name_of_something_i_want_to_install
    

    e.g.

    pacman -S mingw-w64-x86_64-gsl
    

    and from then on the GSL library is automatically found by your MinGW-w64 64-bit compiler!

  5. Open a MinGW-w64 shell:

    a) To build 32-bit things, open the "MinGW-w64 32-bit Shell"

    b) To build 64-bit things, open the "MinGW-w64 64-bit Shell"

  6. Verify that the compiler is working by doing

    gcc -v
    

If you want to use the toolchains (with installed libraries) outside of the MSYS2 environment, all you need to do is add <MSYS2 root>/mingw32/bin or <MSYS2 root>/mingw64/bin to your PATH.

How to set up googleTest as a shared library on Linux

Update for Debian/Ubuntu

Google Mock (package: google-mock) and Google Test (package: libgtest-dev) have been merged. The new package is called googletest. Both old names are still available for backwards compatibility and now depend on the new package googletest.

So, to get your libraries from the package repository, you can do the following:

sudo apt-get install googletest -y
cd /usr/src/googletest
sudo mkdir build
cd build
sudo cmake ..
sudo make
sudo cp googlemock/*.a googlemock/gtest/*.a /usr/lib

After that, you can link against -lgmock (or against -lgmock_main if you do not use a custom main method) and -lpthread. This was sufficient for using Google Test in my cases at least.

If you want the most current version of Google Test, download it from github. After that, the steps are similar:

git clone https://github.com/google/googletest
cd googletest
sudo mkdir build
cd build
sudo cmake ..
sudo make
sudo cp lib/*.a /usr/lib

As you can see, the path where the libraries are created has changed. Keep in mind that the new path might be valid for the package repositories soon, too.

Instead of copying the libraries manually, you could use sudo make install. It "currently" works, but be aware that it did not always work in the past. Also, you don't have control over the target location when using this command and you might not want to pollute /usr/lib.

Is there a native jQuery function to switch elements?

No, there isn't, but you could whip one up:

jQuery.fn.swapWith = function(to) {
    return this.each(function() {
        var copy_to = $(to).clone(true);
        var copy_from = $(this).clone(true);
        $(to).replaceWith(copy_from);
        $(this).replaceWith(copy_to);
    });
};

Usage:

$(selector1).swapWith(selector2);

Note this only works if the selectors only match 1 element each, otherwise it could give weird results.

Why plt.imshow() doesn't display the image?

plt.imshow displays the image on the axes, but if you need to display multiple images you use show() to finish the figure. The next example shows two figures:

import numpy as np
from keras.datasets import mnist
(X_train,y_train),(X_test,y_test) = mnist.load_data()
from matplotlib import pyplot as plt
plt.imshow(X_train[0])
plt.show()
plt.imshow(X_train[1])
plt.show()

In Google Colab, if you comment out the show() method from previous example just a single image will display (the later one connected with X_train[1]).

Here is the content from the help:

plt.show(*args, **kw)
        Display a figure.
        When running in ipython with its pylab mode, display all
        figures and return to the ipython prompt.

        In non-interactive mode, display all figures and block until
        the figures have been closed; in interactive mode it has no
        effect unless figures were created prior to a change from
        non-interactive to interactive mode (not recommended).  In
        that case it displays the figures but does not block.

        A single experimental keyword argument, *block*, may be
        set to True or False to override the blocking behavior
        described above.



plt.imshow(X, cmap=None, norm=None, aspect=None, interpolation=None, alpha=None, vmin=None, vmax=None, origin=None, extent=None, shape=None, filternorm=1, filterrad=4.0, imlim=None, resample=None, url=None, hold=None, data=None, **kwargs)
        Display an image on the axes.

Parameters
----------
X : array_like, shape (n, m) or (n, m, 3) or (n, m, 4)
    Display the image in `X` to current axes.  `X` may be an
    array or a PIL image. If `X` is an array, it
    can have the following shapes and types:

    - MxN -- values to be mapped (float or int)
    - MxNx3 -- RGB (float or uint8)
    - MxNx4 -- RGBA (float or uint8)

    The value for each component of MxNx3 and MxNx4 float arrays
    should be in the range 0.0 to 1.0. MxN arrays are mapped
    to colors based on the `norm` (mapping scalar to scalar)
    and the `cmap` (mapping the normed scalar to a color).

String to LocalDate

As you use Joda Time, you should use DateTimeFormatter:

final DateTimeFormatter dtf = DateTimeFormatter.ofPattern("yyyy-MMM-dd");
final LocalDate dt = dtf.parseLocalDate(yourinput);

If using Java 8 or later, then refer to hertzi's answer

Run local java applet in browser (chrome/firefox) "Your security settings have blocked a local application from running"

  1. Make a jar file from your applet class and META-INF/MANIFEST.MF file.
  2. Sign your jar file with your certificate.
  3. Configure your local site permissions as > file:///C:/ or http: //localhost:8080
  4. Then run your html document on Intenet Explorer on Windows.(Not Google Chrome !)

How to make a div 100% height of the browser window

You can use display: flex and height: 100vh

_x000D_
_x000D_
html, body {_x000D_
  height: 100%;_x000D_
  margin: 0px;_x000D_
}_x000D_
body {_x000D_
  display: flex;_x000D_
}_x000D_
_x000D_
.left, .right {_x000D_
  flex: 1;_x000D_
}_x000D_
_x000D_
.left {_x000D_
  background: orange;_x000D_
}_x000D_
_x000D_
.right {_x000D_
  background: cyan;_x000D_
}
_x000D_
<div class="left">left</div>_x000D_
<div class="right">right</div>
_x000D_
_x000D_
_x000D_

If Else in LINQ

 var result = _context.Employees
                .Where(x => !x.IsDeleted)
                .Where(x => x.ClientId > (clientId > 0 ? clientId - 1 : -1))
                .Where(x => x.ClientId < (clientId > 0 ? clientId + 1 : 1000))
                .Where(x => x.ContractorFlag == employeeFlag);
            return result;

If clientId = 0 we want ALL employees,. but for any clientId between 1 and 999 we want only clients with that ID. I was having issues with seperate LINQ statements not being the same (Deleted/Clients filters need to be on all queries), so by add these two lines it works (all be it until we have 999+ clients - which would be a happy re-factor day!!

jQuery: Performing synchronous AJAX requests

You're using the ajax function incorrectly. Since it's synchronous it'll return the data inline like so:

var remote = $.ajax({
    type: "GET",
    url: remote_url,
    async: false
}).responseText;

How to redirect to Login page when Session is expired in Java web application?

Inside the filter inject this JavaScript which will bring the login page like this. If you don't do this then in your AJAX call you will get login page and the contents of login page will be appended.

Inside your filter or redirect insert this script in response:

String scr = "<script>window.location=\""+request.getContextPath()+"/login.do\"</script>";
response.getWriter().write(scr);

How to break out of a loop in Bash?

while true ; do
    ...
    if [ something ]; then
        break
    fi
done

Run a .bat file using python code

python_test.py

import subprocess
a = subprocess.check_output("batch_1.bat")
print a

This gives output from batch file to be print on the python IDLE/running console. So in batch file you can echo the result in each step to debug the issue. This is also useful in automation when there is an error happening in the batch call, to understand and locate the error easily.(put "echo off" in batch file beginning to avoid printing everything)

batch_1.bat

echo off    
echo "Hello World" 
md newdir 
echo "made new directory"

What certificates are trusted in truststore?

Trust store generally (actually should only contain root CAs but this rule is violated in general) contains the certificates that of the root CAs (public CAs or private CAs). You can verify the list of certs in trust store using

keytool -list -v -keystore truststore.jks

TypeError: a bytes-like object is required, not 'str' in python and CSV

I had the same issue with Python3. My code was writing into io.BytesIO().

Replacing with io.StringIO() solved.

Passing an array of data as an input parameter to an Oracle procedure

If the types of the parameters are all the same (varchar2 for example), you can have a package like this which will do the following:

CREATE OR REPLACE PACKAGE testuser.test_pkg IS

   TYPE assoc_array_varchar2_t IS TABLE OF VARCHAR2(4000) INDEX BY BINARY_INTEGER;

   PROCEDURE your_proc(p_parm IN assoc_array_varchar2_t);

END test_pkg;

CREATE OR REPLACE PACKAGE BODY testuser.test_pkg IS

   PROCEDURE your_proc(p_parm IN assoc_array_varchar2_t) AS
   BEGIN
      FOR i IN p_parm.first .. p_parm.last
      LOOP
         dbms_output.put_line(p_parm(i));
      END LOOP;

   END;

END test_pkg;

Then, to call it you'd need to set up the array and pass it:

DECLARE
  l_array testuser.test_pkg.assoc_array_varchar2_t;
BEGIN
  l_array(0) := 'hello';
  l_array(1) := 'there';  

  testuser.test_pkg.your_proc(l_array);
END;
/

Send JSON data from Javascript to PHP?

This is a summary of the main solutions with easy-to-reproduce code:

Method 1 (application/json or text/plain + JSON.stringify)

var data = {foo: 'blah "!"', bar: 123};
var xhr = new XMLHttpRequest();
xhr.open("POST", "test.php");
xhr.onreadystatechange = function() { if (xhr.readyState === 4 && xhr.status === 200) { console.log(xhr.responseText); } }
xhr.setRequestHeader("Content-type", "application/json") // or "text/plain"
xhr.send(JSON.stringify(data)); 

PHP side, you can get the data with:

print_r(json_decode(file_get_contents('php://input'), true));

Method 2 (x-www-form-urlencoded + JSON.stringify)

var data = {foo: 'blah "!"', bar: 123};
var xhr = new XMLHttpRequest();
xhr.open("POST", "test.php");
xhr.onreadystatechange = function() { if (xhr.readyState === 4 && xhr.status === 200) { console.log(xhr.responseText); } }
xhr.setRequestHeader("Content-type", "application/x-www-form-urlencoded");
xhr.send("json=" + encodeURIComponent(JSON.stringify(data))); 

Note: encodeURIComponent(...) is needed for example if the JSON contains & character.

PHP side, you can get the data with:

print_r(json_decode($_POST['json'], true));

Method 3 (x-www-form-urlencoded + URLSearchParams)

var data = {foo: 'blah "!"', bar: 123};
var xhr = new XMLHttpRequest();
xhr.open("POST", "test.php");
xhr.onreadystatechange = function() { if (xhr.readyState === 4 && xhr.status === 200) { console.log(xhr.responseText); } }
xhr.setRequestHeader("Content-type", "application/x-www-form-urlencoded");
xhr.send(new URLSearchParams(data).toString()); 

PHP side, you can get the data with:

print_r($_POST);

Note: https://caniuse.com/#search=URLSearchParams

Bind event to right mouse click

Just use the event-handler. Something like this should work:

$('.js-my-element').bind('contextmenu', function(e) {
     e.preventDefault();
     alert('The eventhandler will make sure, that the contextmenu dosn&#39;t appear.');
});

How do I horizontally center a span element inside a div

Applying inline-block to the element that is to be centered and applying text-align:center to the parent block did the trick for me.

Works even on <span> tags.

"unmappable character for encoding" warning in Java

Most of the time this compile error comes when unicode(UTF-8 encoded) file compiling

javac -encoding UTF-8 HelloWorld.java

and also You can add this compile option to your IDE ex: Intellij idea
(File>settings>Java Compiler) add as additional command line parameter

enter image description here

-encoding : encoding Set the source file encoding name, such as EUC-JP and UTF-8.. If -encoding is not specified, the platform default converter is used. (DOC)

Can not find the tag library descriptor for "http://java.sun.com/jsp/jstl/core"

This works as well:

<dependency>
    <scope>compile</scope>
    <groupId>javax.servlet.jsp.jstl</groupId>
    <artifactId>jstl-api</artifactId>
    <version>1.2</version>
</dependency>

<dependency>
    <groupId>javax.servlet</groupId>
    <artifactId>jstl</artifactId>
    <version>1.2</version>
</dependency>

so used jstl 1.2 instead of standard.jar together with jstl-api 1.2

Spring: Why do we autowire the interface and not the implemented class?

How does spring know which polymorphic type to use.

As long as there is only a single implementation of the interface and that implementation is annotated with @Component with Spring's component scan enabled, Spring framework can find out the (interface, implementation) pair. If component scan is not enabled, then you have to define the bean explicitly in your application-config.xml (or equivalent spring configuration file).

Do I need @Qualifier or @Resource?

Once you have more than one implementation, then you need to qualify each of them and during auto-wiring, you would need to use the @Qualifier annotation to inject the right implementation, along with @Autowired annotation. If you are using @Resource (J2EE semantics), then you should specify the bean name using the name attribute of this annotation.

Why do we autowire the interface and not the implemented class?

Firstly, it is always a good practice to code to interfaces in general. Secondly, in case of spring, you can inject any implementation at runtime. A typical use case is to inject mock implementation during testing stage.

interface IA
{
  public void someFunction();
}


class B implements IA
{
  public void someFunction()
  {
    //busy code block
  }
  public void someBfunc()
  {
     //doing b things
  }
}


class C implements IA
{
  public void someFunction()
  {
    //busy code block
  }
  public void someCfunc()
  {
     //doing C things
  }
}

class MyRunner
{
     @Autowire
     @Qualifier("b") 
     IA worker;

     ....
     worker.someFunction();
}

Your bean configuration should look like this:

<bean id="b" class="B" />
<bean id="c" class="C" />
<bean id="runner" class="MyRunner" />

Alternatively, if you enabled component scan on the package where these are present, then you should qualify each class with @Component as follows:

interface IA
{
  public void someFunction();
}

@Component(value="b")
class B implements IA
{
  public void someFunction()
  {
    //busy code block
  }
  public void someBfunc()
  {
     //doing b things
  }
}


@Component(value="c")
class C implements IA
{
  public void someFunction()
  {
    //busy code block
  }
  public void someCfunc()
  {
     //doing C things
  }
}

@Component    
class MyRunner
{
     @Autowire
     @Qualifier("b") 
     IA worker;

     ....
     worker.someFunction();
}

Then worker in MyRunner will be injected with an instance of type B.

How to execute .sql file using powershell?

Try to see if SQL snap-ins are present:

get-pssnapin -Registered

Name        : SqlServerCmdletSnapin100
PSVersion   : 2.0
Description : This is a PowerShell snap-in that includes various SQL Server cmdlets.

Name        : SqlServerProviderSnapin100
PSVersion   : 2.0
Description : SQL Server Provider

If so

Add-PSSnapin SqlServerCmdletSnapin100 # here lives Invoke-SqlCmd
Add-PSSnapin SqlServerProviderSnapin100

then you can do something like this:

invoke-sqlcmd -inputfile "c:\mysqlfile.sql" -serverinstance "servername\serverinstance" -database "mydatabase" # the parameter -database can be omitted based on what your sql script does.

How can I find out the current route in Rails?

Based on @AmNaN suggestion (more details):

class ApplicationController < ActionController::Base

 def current_controller?(names)
  names.include?(params[:controller]) unless params[:controller].blank? || false
 end

 helper_method :current_controller?

end

Now you can call it e.g. in a navigation layout for marking list items as active:

<ul class="nav nav-tabs">
  <li role="presentation" class="<%= current_controller?('items') ? 'active' : '' %>">
    <%= link_to user_items_path(current_user) do %>
      <i class="fa fa-cloud-upload"></i>
    <% end %>
  </li>
  <li role="presentation" class="<%= current_controller?('users') ? 'active' : '' %>">
    <%= link_to users_path do %>
      <i class="fa fa-newspaper-o"></i>
    <% end %>
  </li>
  <li role="presentation" class="<%= current_controller?('alerts') ? 'active' : '' %>">
    <%= link_to alerts_path do %>
      <i class="fa fa-bell-o"></i>
    <% end %>
  </li>
</ul>

For the users and alerts routes, current_page? would be enough:

 current_page?(users_path)
 current_page?(alerts_path)

But with nested routes and request for all actions of a controller (comparable with items), current_controller? was the better method for me:

 resources :users do 
  resources :items
 end

The first menu entry is that way active for the following routes:

   /users/x/items        #index
   /users/x/items/x      #show
   /users/x/items/new    #new
   /users/x/items/x/edit #edit

MySql Query Replace NULL with Empty String in Select

Try below ;

  select if(prereq IS NULL ," ",prereq ) from test

Getting XML Node text value with Java DOM

I'd print out the result of an2.getNodeName() as well for debugging purposes. My guess is that your tree crawling code isn't crawling to the nodes that you think it is. That suspicion is enhanced by the lack of checking for node names in your code.

Other than that, the javadoc for Node defines "getNodeValue()" to return null for Nodes of type Element. Therefore, you really should be using getTextContent(). I'm not sure why that wouldn't give you the text that you want.

Perhaps iterate the children of your tag node and see what types are there?

Tried this code and it works for me:

String xml = "<add job=\"351\">\n" +
             "    <tag>foobar</tag>\n" +
             "    <tag>foobar2</tag>\n" +
             "</add>";
DocumentBuilderFactory dbf = DocumentBuilderFactory.newInstance();
DocumentBuilder db = dbf.newDocumentBuilder();
ByteArrayInputStream bis = new ByteArrayInputStream(xml.getBytes());
Document doc = db.parse(bis);
Node n = doc.getFirstChild();
NodeList nl = n.getChildNodes();
Node an,an2;

for (int i=0; i < nl.getLength(); i++) {
    an = nl.item(i);
    if(an.getNodeType()==Node.ELEMENT_NODE) {
        NodeList nl2 = an.getChildNodes();

        for(int i2=0; i2<nl2.getLength(); i2++) {
            an2 = nl2.item(i2);
            // DEBUG PRINTS
            System.out.println(an2.getNodeName() + ": type (" + an2.getNodeType() + "):");
            if(an2.hasChildNodes()) System.out.println(an2.getFirstChild().getTextContent());
            if(an2.hasChildNodes()) System.out.println(an2.getFirstChild().getNodeValue());
            System.out.println(an2.getTextContent());
            System.out.println(an2.getNodeValue());
        }
    }
}

Output was:

#text: type (3): foobar foobar
#text: type (3): foobar2 foobar2

Skip first entry in for loop in python?

I do it like this, even though it looks like a hack it works every time:

ls_of_things = ['apple', 'car', 'truck', 'bike', 'banana']
first = 0
last = len(ls_of_things)
for items in ls_of_things:
    if first == 0
        first = first + 1
        pass
    elif first == last - 1:
        break
    else:
        do_stuff
        first = first + 1
        pass

Check if a string contains an element from a list (of strings)

As I needed to check if there are items from a list in a (long) string, I ended up with this one:

listOfStrings.Any(x => myString.ToUpper().Contains(x.ToUpper()));

Or in vb.net:

listOfStrings.Any(Function(x) myString.ToUpper().Contains(x.ToUpper()))

How to cast List<Object> to List<MyClass>

You can create a new List and add the elements to it:

For example:

List<A> a = getListOfA();
List<Object> newList = new ArrayList<>();
newList.addAll(a);

How to write a SQL DELETE statement with a SELECT statement in the WHERE clause?

Shouldn't you have:

DELETE FROM tableA WHERE entitynum IN (...your select...)

Now you just have a WHERE with no comparison:

DELETE FROM tableA WHERE (...your select...)

So your final query would look like this;

DELETE FROM tableA WHERE entitynum IN (
    SELECT tableA.entitynum FROM tableA q
      INNER JOIN tableB u on (u.qlabel = q.entityrole AND u.fieldnum = q.fieldnum) 
    WHERE (LENGTH(q.memotext) NOT IN (8,9,10) OR q.memotext NOT LIKE '%/%/%')
      AND (u.FldFormat = 'Date')
)

git pull displays "fatal: Couldn't find remote ref refs/heads/xxxx" and hangs up

There are probably some commands to resolve it, but I would start by looking in your .git/config file for references to that branch, and removing them.

How do you convert a jQuery object into a string?

new String(myobj)

If you want to serialize the whole object to string, use JSON.

matching query does not exist Error in Django

As mentioned in Django docs, when get method finds no entry or finds multiple entries, it raises an exception, this is the expected behavior:

get() raises MultipleObjectsReturned if more than one object was found. The MultipleObjectsReturned exception is an attribute of the model class.

get() raises a DoesNotExist exception if an object wasn’t found for the given parameters. This exception is an attribute of the model class.

Using exceptions is a way to handle this problem, but I actually don't like the ugly try-except block. An alternative solution, and cleaner to me, is to use the combination of filter + first.

user = UniversityDetails.objects.filter(email=email).first()

When you do .first() to an empty queryset it returns None. This way you can have the same effect in a single line.

The only difference between catching the exception and using this method occurs when you have multiple entries, the former will raise an exception while the latter will set the first element, but as you are using get I may assume we won't fall on this situation.

Note that first method was added on Django 1.6.

Displaying output of a remote command with Ansible

I'm not sure about the syntax of your specific commands (e.g., vagrant, etc), but in general...

Just register Ansible's (not-normally-shown) JSON output to a variable, then display each variable's stdout_lines attribute:

- name: Generate SSH keys for vagrant user
  user: name=vagrant generate_ssh_key=yes ssh_key_bits=2048
  register: vagrant
- debug: var=vagrant.stdout_lines

- name: Show SSH public key
  command: /bin/cat $home_directory/.ssh/id_rsa.pub
  register: cat
- debug: var=cat.stdout_lines

- name: Wait for user to copy SSH public key
  pause: prompt="Please add the SSH public key above to your GitHub account"
  register: pause
- debug: var=pause.stdout_lines

Excel VBA: AutoFill Multiple Cells with Formulas

The approach you're looking for is FillDown. Another way so you don't have to kick your head off every time is to store formulas in an array of strings. Combining them gives you a powerful method of inputting formulas by the multitude. Code follows:

Sub FillDown()

    Dim strFormulas(1 To 3) As Variant

    With ThisWorkbook.Sheets("Sheet1")
        strFormulas(1) = "=SUM(A2:B2)"
        strFormulas(2) = "=PRODUCT(A2:B2)"
        strFormulas(3) = "=A2/B2"

        .Range("C2:E2").Formula = strFormulas
        .Range("C2:E11").FillDown
    End With

End Sub

Screenshots:

Result as of line: .Range("C2:E2").Formula = strFormulas:

enter image description here

Result as of line: .Range("C2:E11").FillDown:

enter image description here

Of course, you can make it dynamic by storing the last row into a variable and turning it to something like .Range("C2:E" & LRow).FillDown, much like what you did.

Hope this helps!

jQuery select change event get selected option

$('select').on('change', function (e) {
    var optionSelected = $("option:selected", this);
    var valueSelected = this.value;
    ....
});

Datanode process not running in Hadoop

  1. Stop the dfs and yarn first.
  2. Remove the datanode and namenode directories as specified in the core-site.xml file.
  3. Re-create the directories.
  4. Then re-start the dfs and the yarn as follows.

    start-dfs.sh

    start-yarn.sh

    mr-jobhistory-daemon.sh start historyserver

    Hope this works fine.

Create thumbnail image

Here is an example to convert high res image into thumbnail size-

protected void Button1_Click(object sender, EventArgs e)
{
    //----------        Getting the Image File
    System.Drawing.Image img = System.Drawing.Image.FromFile(Server.MapPath("~/profile/Avatar.jpg"));

    //----------        Getting Size of Original Image
    double imgHeight = img.Size.Height;
    double imgWidth = img.Size.Width;

    //----------        Getting Decreased Size
    double x = imgWidth / 200;
    int newWidth = Convert.ToInt32(imgWidth / x);
    int newHeight = Convert.ToInt32(imgHeight / x);

    //----------        Creating Small Image
    System.Drawing.Image.GetThumbnailImageAbort myCallback = new System.Drawing.Image.GetThumbnailImageAbort(ThumbnailCallback);
    System.Drawing.Image myThumbnail = img.GetThumbnailImage(newWidth, newHeight, myCallback, IntPtr.Zero);

    //----------        Saving Image
    myThumbnail.Save(Server.MapPath("~/profile/NewImage.jpg"));
}
public bool ThumbnailCallback()
{
    return false;
}

Source- http://iknowledgeboy.blogspot.in/2014/03/c-creating-thumbnail-of-large-image-by.html

Java/Groovy - simple date reformatting

oldDate is not in the format of the SimpleDateFormat you are using to parse it.

Try this format: dd-MMM-yyyy - It matches what you're trying to parse.

What is "runtime"?

The runtime or execution environment is the part of a language implementation which executes code and is present at run-time; the compile-time part of the implementation is called the translation environment in the C standard.

Examples:

  • the Java runtime consists of the virtual machine and the standard library

  • a common C runtime consists of the loader (which is part of the operating system) and the runtime library, which implements the parts of the C language which are not built into the executable by the compiler; in hosted environments, this includes most parts of the standard library

Maven Error: Could not find or load main class

specify the main class location in pom under plugins

<build>
        <plugins>
            <plugin>
                <groupId>org.apache.maven.plugins</groupId>
                <artifactId>maven-jar-plugin</artifactId>
                <version>2.4</version>
                <configuration>
                    <archive>
                        <index>true</index>
                        <manifest>
                            <mainClass>com.example.hadoop.wordCount.WordCountApp</mainClass>
                        </manifest>
                    </archive>
                </configuration>
            </plugin>
        </plugins>
    </build>

No numeric types to aggregate - change in groupby() behaviour?

How are you generating your data?

See how the output shows that your data is of 'object' type? the groupby operations specifically check whether each column is a numeric dtype first.

In [31]: data
Out[31]: 
<class 'pandas.core.frame.DataFrame'>
DatetimeIndex: 2557 entries, 2004-01-01 00:00:00 to 2010-12-31 00:00:00
Freq: <1 DateOffset>
Columns: 360 entries, -89.75 to 89.75
dtypes: object(360)

look ?


Did you initialize an empty DataFrame first and then filled it? If so that's probably why it changed with the new version as before 0.9 empty DataFrames were initialized to float type but now they are of object type. If so you can change the initialization to DataFrame(dtype=float).

You can also call frame.astype(float)

How to compare files from two different branches?

There are many ways to compare files from two different branches:

  • Option 1: If you want to compare the file from n specific branch to another specific branch:

    git diff branch1name branch2name path/to/file
    

    Example:

    git diff mybranch/myfile.cs mysecondbranch/myfile.cs
    

    In this example you are comparing the file in “mybranch” branch to the file in the “mysecondbranch” branch.

  • Option 2: Simple way:

     git diff branch1:file branch2:file
    

    Example:

     git diff mybranch:myfile.cs mysecondbranch:myfile.cs
    

    This example is similar to the option 1.

  • Option 3: If you want to compare your current working directory to some branch:

    git diff ..someBranch path/to/file
    

    Example:

    git diff ..master myfile.cs
    

    In this example you are comparing the file from your actual branch to the file in the master branch.

How can I upgrade specific packages using pip and a requirements file?

If you only want to upgrade one specific package called somepackage, the command you should use in recent versions of pip is

pip install --upgrade --upgrade-strategy only-if-needed somepackage

This is very useful when you develop an application in Django that currently will only work with a specific version of Django (say Django=1.9.x) and want to upgrade some dependent package with a bug-fix/new feature and the upgraded package depends on Django (but it works with, say, any version of Django after 1.5).

The default behavior of pip install --upgrade django-some-package would be to upgrade Django to the latest version available which could otherwise break your application, though with the --upgrade-strategy only-if-needed dependent packages will now only be upgraded as necessary.

What is the best method to merge two PHP objects?

Let's keep it simple!

function copy_properties($from, $to, $fields = null) {
    // copies properties/elements (overwrites duplicates)
    // can take arrays or objects 
    // if fields is set (an array), will only copy keys listed in that array
    // returns $to with the added/replaced properties/keys
    $from_array = is_array($from) ? $from : get_object_vars($from);
    foreach($from_array as $key => $val) {
        if(!is_array($fields) or in_array($key, $fields)) {
            if(is_object($to)) {
                $to->$key = $val;
            } else {
                $to[$key] = $val;
            }
        }
    }
    return($to);
}

If that doesn't answer your question, it will surely help towards the answer. Credit for the code above goes to myself :)

Adding a background image to a <div> element

<div class="foo">Foo Bar</div>

and in your CSS file:

.foo {
    background-image: url("images/foo.png");
}

Python: Finding differences between elements of a list

A functional approach:

>>> import operator
>>> a = [1,3,5,7,11,13,17,21]
>>> map(operator.sub, a[1:], a[:-1])
[2, 2, 2, 4, 2, 4, 4]

Using generator:

>>> import operator, itertools
>>> g1,g2 = itertools.tee((x*x for x in xrange(5)),2)
>>> list(itertools.imap(operator.sub, itertools.islice(g1,1,None), g2))
[1, 3, 5, 7]

Using indices:

>>> [a[i+1]-a[i] for i in xrange(len(a)-1)]
[2, 2, 2, 4, 2, 4, 4]

How to resolve Value cannot be null. Parameter name: source in linq?

Value cannot be null. Parameter name: source

Above error comes in situation when you are querying the collection which is null.

For demonstration below code will result in such an exception.

Console.WriteLine("Hello World");
IEnumerable<int> list = null;
list.Where(d => d ==4).FirstOrDefault();

Here is the output of the above code.

Hello World Run-time exception (line 11): Value cannot be null. Parameter name: source

Stack Trace:

[System.ArgumentNullException: Value cannot be null. Parameter name: source] at Program.Main(): line 11

In your case ListMetadataKor is null. Here is the fiddle if you want to play around.

Order of execution of tests in TestNG

In case you happen to use additional stuff like dependsOnMethods, you may want to define the entire @Test flow in your testng.xml file. AFAIK, the order defined in your suite XML file (testng.xml) will override all other ordering strategies.

How to reset (clear) form through JavaScript?

Note, function form.reset() will not work if some input tag in the form have attribute name='reset'

How to output (to a log) a multi-level array in a format that is human-readable?

Simple stuff:

Using print_r, var_dump or var_export should do it pretty nicely if you look at the result in view-source mode not in HTML mode or as @Joel Larson said if you wrap everything in a <pre> tag.

print_r is best for readability but it doesn't print null/false values.

var_dump is best for checking types of values and lengths and null/false values.

var_export is simmilar to var_dump but it can be used to get the dumped string.

The format returned by any of these is indented correctly in the source code and var_export can be used for logging since it can be used to return the dumped string.

Advanced stuff:

Use the xdebug plug-in for PHP this prints var_dumps as HTML formatted strings not as raw dump format and also allows you to supply a custom function you want to use for formatting.

Why dividing two integers doesn't get a float?

Chapter and verse

6.5.5 Multiplicative operators
...
6 When integers are divided, the result of the / operator is the algebraic quotient with any fractional part discarded.105) If the quotient a/b is representable, the expression (a/b)*b + a%b shall equal a; otherwise, the behavior of both a/b and a%b is unde?ned.

105) This is often called ‘‘truncation toward zero’’.

Dividing an integer by an integer gives an integer result. 1/2 yields 0; assigning this result to a floating-point variable gives 0.0. To get a floating-point result, at least one of the operands must be a floating-point type. b = a / 350.0f; should give you the result you want.

jQuery - Getting form values for ajax POST

$("#registerSubmit").serialize() // returns all the data in your form
$.ajax({
     type: "POST",
     url: 'your url',
     data: $("#registerSubmit").serialize(),
     success: function() {
          //success message mybe...
     }
});

Server Discovery And Monitoring engine is deprecated

Add the useUnifiedTopology option and set it to true.

Set other 3 configuration of the mongoose.connect options which will deal with other remaining DeprecationWarning.

This configuration works for me!

const url = 'mongodb://localhost:27017/db_name';
mongoose.connect(
    url, 
    { 
        useNewUrlParser: true, 
        useUnifiedTopology: true,
        useCreateIndex: true,
        useFindAndModify: false
    }
)

This will solve 4 DeprecationWarning.

  1. Current URL string parser is deprecated, and will be removed in a future version. To use the new parser, pass option { useNewUrlParser: true } to MongoClient.connect.
  2. Current Server Discovery and Monitoring engine is deprecated, and will be removed in a future version. To use the new Server Discover and Monitoring engine, pass option { useUnifiedTopology: true } to the MongoClient constructor.
  3. Collection.ensureIndex is deprecated. Use createIndexes instead.
  4. DeprecationWarning: Mongoose: findOneAndUpdate() and findOneAndDelete() without the useFindAndModify option set to false are deprecated. See: https://mongoosejs.com/docs/deprecations.html#-findandmodify-.

Hope it helps.

How to create a numpy array of all True or all False?

Quickly ran a timeit to see, if there are any differences between the np.full and np.ones version.

Answer: No

import timeit

n_array, n_test = 1000, 10000
setup = f"import numpy as np; n = {n_array};"

print(f"np.ones: {timeit.timeit('np.ones((n, n), dtype=bool)', number=n_test, setup=setup)}s")
print(f"np.full: {timeit.timeit('np.full((n, n), True)', number=n_test, setup=setup)}s")

Result:

np.ones: 0.38416870904620737s
np.full: 0.38430388597771525s


IMPORTANT

Regarding the post about np.empty (and I cannot comment, as my reputation is too low):

DON'T DO THAT. DON'T USE np.empty to initialize an all-True array

As the array is empty, the memory is not written and there is no guarantee, what your values will be, e.g.

>>> print(np.empty((4,4), dtype=bool))
[[ True  True  True  True]
 [ True  True  True  True]
 [ True  True  True  True]
 [ True  True False False]]

How to 'restart' an android application programmatically

Checkout intent properties like no history , clear back stack etc ... Intent.setFlags

Intent mStartActivity = new Intent(HomeActivity.this, SplashScreen.class);
int mPendingIntentId = 123456;
PendingIntent mPendingIntent = PendingIntent.getActivity(HomeActivity.this, mPendingIntentId, mStartActivity,
PendingIntent.FLAG_CANCEL_CURRENT);
AlarmManager mgr = (AlarmManager) HomeActivity.this.getSystemService(Context.ALARM_SERVICE);
mgr.set(AlarmManager.RTC, System.currentTimeMillis() + 100, mPendingIntent);
System.exit(0);

How to navigate back to the last cursor position in Visual Studio Code?

?+U Undo last cursor operation

You can also try ctrl+-

BTW all the shortcuts is here https://code.visualstudio.com/shortcuts/keyboard-shortcuts-macos.pdf This is really useful!

In Excel, how do I extract last four letters of a ten letter string?

No need to use a macro. Supposing your first string is in A1.

=RIGHT(A1, 4)

Drag this down and you will get your four last characters.

Edit: To be sure, if you ever have sequences like 'ABC DEF' and want the last four LETTERS and not CHARACTERS you might want to use trimspaces()

=RIGHT(TRIMSPACES(A1), 4)

Edit: As per brettdj's suggestion, you may want to check that your string is actually 4-character long or more:

=IF(TRIMSPACES(A1)>=4, RIGHT(TRIMSPACES(A1), 4), TRIMSPACES(A1))

java.lang.ClassNotFoundException: org.springframework.web.servlet.DispatcherServlet

You can use GlassFish server and the error will be resolved. I tried with tomcat7 and tomcat8 but this error was coming continuously but resolved with GlassFish. I think it's a problem with server.

These are the results with tomcat7: Results with tomcat7

Here are the results with GlassFish: Results with GlassFish

How to take last four characters from a varchar?

SUBSTR(column, LENGTH(column) - 3, 4)

LENGTH returns length of string and SUBSTR returns 4 characters from "the position length - 4"

How to read Data from Excel sheet in selenium webdriver

Your problem is that log4j has not been initialized. It does not affect the outcome of you application in any way, so it's safe to ignore or just initialize Log4J, see: How to initialize log4j properly?

SQL Server Case Statement when IS NULL

  case isnull(B.[stat],0)
  when 0 then dateadd(dd,10,(c.[Eventdate]))
  end

you can add in else statement if you want to add 30 days to the same .

R solve:system is exactly singular

Using solve with a single parameter is a request to invert a matrix. The error message is telling you that your matrix is singular and cannot be inverted.

How to import existing Android project into Eclipse?

  1. File ? Import ? General ? Existing Projects into Workspace ? Next
  2. Select root directory: /path/to/project
  3. Projects ? Select All
  4. Uncheck Copy projects into workspace and Add project to working sets
  5. Finish

Remove Server Response Header IIS7

To remove the Server: header, go to Global.asax, find/create the Application_PreSendRequestHeaders event and add a line as follows (thanks to BK and this blog this will also not fail on the Cassini / local dev):

protected void Application_PreSendRequestHeaders(object sender, EventArgs e)
{
    // Remove the "Server" HTTP Header from response
    HttpApplication app = sender as HttpApplication;
    if (null != app && null != app.Request && !app.Request.IsLocal &&
        null != app.Context && null != app.Context.Response)
    {
        NameValueCollection headers = app.Context.Response.Headers;
        if (null != headers)
        {
            headers.Remove("Server");
        }
    }
}

If you want a complete solution to remove all related headers on Azure/IIS7 and also works with Cassini, see this link, which shows the best way to disable these headers without using HttpModules or URLScan.

How to export table data in MySql Workbench to csv?

You can select the rows from the table you want to export in the MySQL Workbench SQL Editor. You will find an Export button in the resultset that will allow you to export the records to a CSV file, as shown in the following image:

MySQL Workbench Export Resultset Button

Please also keep in mind that by default MySQL Workbench limits the size of the resultset to 1000 records. You can easily change that in the Preferences dialog:

MySQL Workbench Preferences Dialog

Hope this helps.

Add a column to a table, if it does not already exist

When checking for a column in another database, you can simply include the database name:

IF NOT EXISTS (
  SELECT * 
  FROM   DatabaseName.sys.columns 
  WHERE  object_id = OBJECT_ID(N'[DatabaseName].[dbo].[TableName]') 
         AND name = 'ColumnName'
)

Get string character by index - Java

You could use the String.charAt(int index) method result as the parameter for String.valueOf(char c).

String.valueOf(myString.charAt(3)) // This will return a string of the character on the 3rd position.

How do I get the time difference between two DateTime objects using C#?

You can use in following manner to achieve difference between two Datetime Object. Suppose there are DateTime objects dt1 and dt2 then the code.

TimeSpan diff = dt2.Subtract(dt1);

How to access SOAP services from iPhone

I've historically rolled my own access at a low level (XML generation and parsing) to deal with the occasional need to do SOAP style requests from Objective-C. That said, there's a library available called SOAPClient (soapclient) that is open source (BSD licensed) and available on Google Code (mac-soapclient) that might be of interest.

I won't attest to it's abilities or effectiveness, as I've never used it or had to work with it's API's, but it is available and might provide a quick solution for you depending on your needs.

Apple had, at one time, a very broken utility called WS-MakeStubs. I don't think it's available on the iPhone, but you might also be interested in an open-source library intended to replace that - code generate out Objective-C for interacting with a SOAP client. Again, I haven't used it - but I've marked it down in my notes: wsdl2objc

How add unique key to existing table (with non uniques rows)

Either create an auto-increment id or a UNIQUE id and add it to the natural key you are talking about with the 4 fields. this will make every row in the table unique...

What primitive data type is time_t?

Unfortunately, it's not completely portable. It's usually integral, but it can be any "integer or real-floating type".

Spring can you autowire inside an abstract class?

What if you need any database operation in SuperGirl you would inject it again into SuperGirl.

I think the main idea is using the same object reference in different classes. So what about this:

//There is no annotation about Spring in the abstract part.
abstract class SuperMan {


    private final DatabaseService databaseService;

    public SuperMan(DatabaseService databaseService) {
     this.databaseService = databaseService;
    }

    abstract void Fly();

    protected void doSuperPowerAction(Thing thing) {

        //busy code

        databaseService.save(thing);

    }
}

@Component
public class SuperGirl extends SuperMan {

private final DatabaseService databaseService;

@Autowired
public SuperGirl (DatabaseService databaseService) {
     super(databaseService);
     this.databaseService = databaseService;
    }

@Override
public void Fly() {
    //busy code
}

public doSomethingSuperGirlDoes() {

    //busy code

    doSuperPowerAction(thing)

}

In my opinion, inject once run everywhere :)

How to delete a stash created with git stash create?

git stash drop takes no parameter - which drops the top stash - or a stash reference which looks like: stash@{n} which n nominates which stash to drop. You can't pass a commit id to git stash drop.

git stash drop            # drop top hash, stash@{0}
git stash drop stash@{n}  # drop specific stash - see git stash list

Dropping a stash will change the stash@{n} designations of all stashes further down the stack.

I'm not sure why you think need to drop a stash because if you are using stash create a stash entry isn't created for your "stash" so there isn't anything to drop.

Cause of No suitable driver found for

I had the same problem with spring, commons-dbcp and oracle 10g. Using this URL I got the 'no suitable driver' error: jdbc:oracle:[email protected]:1521:kinangop

The above URL is missing a full colon just before the @. After correcting that, the error disappeared.

Make Vim show ALL white spaces as a character

:match CursorLine /\s\+/

avoids the "you have to search for spaces to get them to show up" bit but afaict can't be configured to do non-hilighting things to the spaces. CursorLine can be any hilighting group and in the default theme it's a plain underline.

jQuery val is undefined?

try: $('#editorTitle').attr('value') ?

Single quotes vs. double quotes in C or C++

In C and in C++ single quotes identify a single character, while double quotes create a string literal. 'a' is a single a character literal, while "a" is a string literal containing an 'a' and a null terminator (that is a 2 char array).

In C++ the type of a character literal is char, but note that in C, the type of a character literal is int, that is sizeof 'a' is 4 in an architecture where ints are 32bit (and CHAR_BIT is 8), while sizeof(char) is 1 everywhere.

How to Decode Json object in laravel and apply foreach loop on that in laravel

your string is NOT a valid json to start with.

a valid json will be,

{
    "area": [
        {
            "area": "kothrud"
        },
        {
            "area": "katraj"
        }
    ]
}

if you do a json_decode, it will yield,

stdClass Object
(
    [area] => Array
        (
            [0] => stdClass Object
                (
                    [area] => kothrud
                )

            [1] => stdClass Object
                (
                    [area] => katraj
                )

        )

)

Update: to use

$string = '

{
    "area": [
        {
            "area": "kothrud"
        },
        {
            "area": "katraj"
        }
    ]
}

';
            $area = json_decode($string, true);

            foreach($area['area'] as $i => $v)
            {
                echo $v['area'].'<br/>';
            }

Output:

kothrud
katraj

Update #2:

for that true:

When TRUE, returned objects will be converted into associative arrays. for more information, click here

What's the difference between HTML 'hidden' and 'aria-hidden' attributes?

ARIA (Accessible Rich Internet Applications) defines a way to make Web content and Web applications more accessible to people with disabilities.

The hidden attribute is new in HTML5 and tells browsers not to display the element. The aria-hidden property tells screen-readers if they should ignore the element. Have a look at the w3 docs for more details:

https://www.w3.org/WAI/PF/aria/states_and_properties#aria-hidden

Using these standards can make it easier for disabled people to use the web.

JavaScript: filter() for Objects

If you wish to mutate the same object rather than create a new one.

The following example will delete all 0 or empty values:

const sev = { a: 1, b: 0, c: 3 };
const deleteKeysBy = (obj, predicate) =>
  Object.keys(obj)
    .forEach( (key) => {
      if (predicate(obj[key])) {
        delete(obj[key]);
      }
    });

deleteKeysBy(sev, val => !val);

Reading From A Text File - Batch

Your code "for /f "tokens=* delims=" %%x in (a.txt) do echo %%x" will work on most Windows Operating Systems unless you have modified commands.

So you could instead "cd" into the directory to read from before executing the "for /f" command to follow out the string. For instance if the file "a.txt" is located at C:\documents and settings\%USERNAME%\desktop\a.txt then you'd use the following.

cd "C:\documents and settings\%USERNAME%\desktop"
for /f "tokens=* delims=" %%x in (a.txt) do echo %%x
echo.
echo.
echo.
pause >nul
exit

But since this doesn't work on your computer for x reason there is an easier and more efficient way of doing this. Using the "type" command.

@echo off
color a
cls
cd "C:\documents and settings\%USERNAME%\desktop"
type a.txt
echo.
echo.
pause >nul
exit

Or if you'd like them to select the file from which to write in the batch you could do the following.

@echo off
:A
color a
cls
echo Choose the file that you want to read.
echo.
echo.
tree
echo.
echo.
echo.
set file=
set /p file=File:
cls
echo Reading from %file%
echo.
type %file%
echo.
echo.
echo.
set re=
set /p re=Y/N?:
if %re%==Y goto :A
if %re%==y goto :A
exit

WPF: simple TextBox data binding

Your Window is not implementing the necessary data binding notifications that the grid requires to use it as a data source, namely the INotifyPropertyChanged interface.

Your "Name2" string needs also to be a property and not a public variable, as data binding is for use with properties.

Implementing the necessary interfaces for using an object as a data source can be found here.

What tool can decompile a DLL into C++ source code?

I think a C++ DLL is a machine code file. Therefore decompiling will only result in assembler code. If you can read that and create C++ from that you're good to go.

how to inherit Constructor from super class to sub class

You inherit class attributes, not class constructors .This is how it goes :

If no constructor is added in the super class, if no then the compiler adds a no argument contructor. This default constructor is invoked implicitly whenever a new instance of the sub class is created . Here the sub class may or may not have constructor, all is ok .

if a constructor is provided in the super class, the compiler will see if it is a no arg constructor or a constructor with parameters.

if no args, then the compiler will invoke it for any sub class instanciation . Here also the sub class may or may not have constructor, all is ok .

if 1 or more contructors in the parent class have parameters and no args constructor is absent, then the subclass has to have at least 1 constructor where an implicit call for the parent class construct is made via super (parent_contractor params) .

this way you are sure that the inherited class attributes are always instanciated .

How to enable explicit_defaults_for_timestamp?

On Windows -- open my.ini file, present at "C:\ProgramData\MySQL\MySQL Server 5.6", find "[mysqld]" (without quotes) in next line add explicit_defaults_for_timestamp and then save the changes.

Angular JS update input field after change

I'm guessing that when you enter a value into the totals field that value expression somehow gets overwritten.

However, you can take an alternative approach: Create a field for the total value and when either one or two changes update that field.

<li>Total <input type="text" ng-model="total">{{total}}</li>

And change the javascript:

function TodoCtrl($scope) {
    $scope.$watch('one * two', function (value) {
        $scope.total = value;
    });
}

Example fiddle here.

How to check if an NSDictionary or NSMutableDictionary contains a key?

Solution for swift 4.2

So, if you just want to answer the question whether the dictionary contains the key, ask:

let keyExists = dict[key] != nil

If you want the value and you know the dictionary contains the key, say:

let val = dict[key]!

But if, as usually happens, you don't know it contains the key - you want to fetch it and use it, but only if it exists - then use something like if let:

if let val = dict[key] {
    // now val is not nil and the Optional has been unwrapped, so use it
}

JSON string to JS object

the string in your question is not a valid json string. From json.org website:

JSON is built on two structures:

* A collection of name/value pairs. In various languages, this is 
  realized as an object, record, struct, dictionary, hash table, keyed list, or
  associative array.
* An ordered list of values. In most languages, this is realized as an
  array, vector, list, or sequence.

Basically a json string will always start with either { or [.

Then as @Andy E and @Cryo said you can parse the string with json2.js or some other libraries.

IMHO you should avoid eval because it will any javascript program, so you might incur in security issues.

How to install popper.js with Bootstrap 4?

Instead of remotely putting popper js from CDN you can directly install it in your angular project.

Try this.

npm install popper.js --save 

This query installs an updated version of popper.js Don't mention any version there, it will work for you.

LaTeX table too wide. How to make it fit?

Use p{width} column specifier: e.g. \begin{tabular}{ l p{10cm} } will put column's content into 10cm-wide parbox, and the text will be properly broken to several lines, like in normal paragraph.

You can also use tabular* environment to specify width for the entire table.

Shell script "for" loop syntax

If the seq command available on your system:

for i in `seq 2 $max`
do
  echo "output: $i"
done

If not, then use poor man's seq with perl:

seq=`perl -e "\$,=' ';print 2..$max"`
for i in $seq
do
  echo "output: $i"
done

Watch those quote marks.

How do you create vectors with specific intervals in R?

Usually, we want to divide our vector into a number of intervals. In this case, you can use a function where (a) is a vector and (b) is the number of intervals. (Let's suppose you want 4 intervals)

a <- 1:10
b <- 4

FunctionIntervalM <- function(a,b) {
  seq(from=min(a), to = max(a), by = (max(a)-min(a))/b)
}

FunctionIntervalM(a,b)
# 1.00  3.25  5.50  7.75 10.00

Therefore you have 4 intervals:

1.00 - 3.25 
3.25 - 5.50
5.50 - 7.75
7.75 - 10.00

You can also use a cut function

  cut(a, 4)

# (0.991,3.25] (0.991,3.25] (0.991,3.25] (3.25,5.5]   (3.25,5.5]   (5.5,7.75]  
# (5.5,7.75]   (7.75,10]    (7.75,10]    (7.75,10]   
#Levels: (0.991,3.25] (3.25,5.5] (5.5,7.75] (7.75,10]

Generate preview image from Video file?

I recommend php-ffmpeg library.

Extracting image

You can extract a frame at any timecode using the FFMpeg\Media\Video::frame method.

This code returns a FFMpeg\Media\Frame instance corresponding to the second 42. You can pass any FFMpeg\Coordinate\TimeCode as argument, see dedicated documentation below for more information.

$frame = $video->frame(FFMpeg\Coordinate\TimeCode::fromSeconds(42));
$frame->save('image.jpg');

If you want to extract multiple images from the video, you can use the following filter:

$video
    ->filters()
    ->extractMultipleFrames(FFMpeg\Filters\Video\ExtractMultipleFramesFilter::FRAMERATE_EVERY_10SEC, '/path/to/destination/folder/')
    ->synchronize();

$video
    ->save(new FFMpeg\Format\Video\X264(), '/path/to/new/file');

By default, this will save the frames as jpg images.

You are able to override this using setFrameFileType to save the frames in another format:

$frameFileType = 'jpg'; // either 'jpg', 'jpeg' or 'png'
$filter = new ExtractMultipleFramesFilter($frameRate, $destinationFolder);
$filter->setFrameFileType($frameFileType);

$video->addFilter($filter);

AWS CLI S3 A client error (403) occurred when calling the HeadObject operation: Forbidden

I figured it out. I had an error in my cloud formation template that was creating the EC2 instances. As a result, the EC2 instances that were trying to access the above code deploy buckets, were in different regions (not us-west-2). It seems like the access policies on the buckets (owned by Amazon) only allow access from the region they belong in. When I fixed the error in my template (it was wrong parameter map), the error disappeared

How to know which is running in Jupyter notebook?

import sys
print(sys.executable)
print(sys.version)
print(sys.version_info)

Seen below :- output when i run JupyterNotebook outside a CONDA venv

/home/dhankar/anaconda2/bin/python
2.7.12 |Anaconda 4.2.0 (64-bit)| (default, Jul  2 2016, 17:42:40) 
[GCC 4.4.7 20120313 (Red Hat 4.4.7-1)]
sys.version_info(major=2, minor=7, micro=12, releaselevel='final', serial=0)
 

Seen below when i run same JupyterNoteBook within a CONDA Venv created with command --

conda create -n py35 python=3.5 ## Here - py35 , is name of my VENV

in my Jupyter Notebook it prints :-

/home/dhankar/anaconda2/envs/py35/bin/python
3.5.2 |Continuum Analytics, Inc.| (default, Jul  2 2016, 17:53:06) 
[GCC 4.4.7 20120313 (Red Hat 4.4.7-1)]
sys.version_info(major=3, minor=5, micro=2, releaselevel='final', serial=0)

also if you already have various VENV's created with different versions of Python you switch to the desired Kernel by choosing KERNEL >> CHANGE KERNEL from within the JupyterNotebook menu... JupyterNotebookScreencapture

Also to install ipykernel within an existing CONDA Virtual Environment -

http://ipython.readthedocs.io/en/stable/install/kernel_install.html#kernels-for-different-environments

Source --- https://github.com/jupyter/notebook/issues/1524

 $ /path/to/python -m  ipykernel install --help
 usage: ipython-kernel-install [-h] [--user] [--name NAME]
                          [--display-name DISPLAY_NAME]
                          [--profile PROFILE] [--prefix PREFIX]
                          [--sys-prefix]

Install the IPython kernel spec.

optional arguments: -h, --help show this help message and exit --user Install for the current user instead of system-wide --name NAME Specify a name for the kernelspec. This is needed to have multiple IPython kernels at the same time. --display-name DISPLAY_NAME Specify the display name for the kernelspec. This is helpful when you have multiple IPython kernels. --profile PROFILE Specify an IPython profile to load. This can be used to create custom versions of the kernel. --prefix PREFIX Specify an install prefix for the kernelspec. This is needed to install into a non-default location, such as a conda/virtual-env. --sys-prefix Install to Python's sys.prefix. Shorthand for --prefix='/Users/bussonniermatthias/anaconda'. For use in conda/virtual-envs.

How to change the name of a Django app?

In many cases, I believe @allcaps's answer works well.

However, sometimes it is necessary to actually rename an app, e.g. to improve code readability or prevent confusion.

Most of the other answers involve either manual database manipulation or tinkering with existing migrations, which I do not like very much.

As an alternative, I like to create a new app with the desired name, copy everything over, make sure it works, then remove the original app:

  1. Start a new app with the desired name, and copy all code from the original app into that. Make sure you fix the namespaced stuff, in the newly copied code, to match the new app name.

  2. makemigrations and migrate

  3. Create a data migration that copies the relevant data from the original app's tables into the new app's tables, and migrate again.

At this point, everything still works, because the original app and its data are still in place.

  1. Now you can refactor all the dependent code, so it only makes use of the new app. See other answers for examples of what to look out for.

  2. Once you are certain that everything works, you can remove the original app.

This has the advantage that every step uses the normal Django migration mechanism, without manual database manipulation, and we can track everything in source control. In addition, we keep the original app and its data in place until we are sure everything works.

How to pad a string with leading zeros in Python 3

Since python 3.6 you can use fstring :

>>> length = 1
>>> print(f'length = {length:03}')
length = 001

Passing additional variables from command line to make

From the manual:

Variables in make can come from the environment in which make is run. Every environment variable that make sees when it starts up is transformed into a make variable with the same name and value. However, an explicit assignment in the makefile, or with a command argument, overrides the environment.

So you can do (from bash):

FOOBAR=1 make

resulting in a variable FOOBAR in your Makefile.

How to create range in Swift?

(1..<10)

returns...

Range = 1..<10

How can I exclude a directory from Visual Studio Code "Explore" tab?

In newer versions of VSCode this moved to a folder-specific configuration block.

  • Go to File -> Preferences -> Settings (or on Mac Code -> Preferences -> Settings)
  • Pick the Folder Settings tab

Then add a "files.exclude" block, listing the directory globs you would like to exclude:

{
    "files.exclude": {
        "**/bin": true,
        "**/obj": true
    },
}

enter image description here

How to avoid the "Circular view path" exception with Spring MVC test

In my case, I was trying out Kotlin + Spring boot and I got into the Circular View Path issue. All the suggestions I got online could not help, until I tried the below:

Originally I had annotated my controller using @Controller

import org.springframework.stereotype.Controller

I then replaced @Controller with @RestController

import org.springframework.web.bind.annotation.RestController

And it worked.

Add text to Existing PDF using Python

Leveraging David Dehghan's answer above, the following works in Python 2.7.13:

from PyPDF2 import PdfFileWriter, PdfFileReader, PdfFileMerger

import StringIO

from reportlab.pdfgen import canvas
from reportlab.lib.pagesizes import letter

packet = StringIO.StringIO()
# create a new PDF with Reportlab
can = canvas.Canvas(packet, pagesize=letter)
can.drawString(290, 720, "Hello world")
can.save()

#move to the beginning of the StringIO buffer
packet.seek(0)
new_pdf = PdfFileReader(packet)
# read your existing PDF
existing_pdf = PdfFileReader("original.pdf")
output = PdfFileWriter()
# add the "watermark" (which is the new pdf) on the existing page
page = existing_pdf.getPage(0)
page.mergePage(new_pdf.getPage(0))
output.addPage(page)
# finally, write "output" to a real file
outputStream = open("destination.pdf", "wb")
output.write(outputStream)
outputStream.close()

How do I implement interfaces in python?

I invite you to explore what Python 3.8 has to offer for the subject matter in form of Structural subtyping (static duck typing) (PEP 544)

See the short description https://docs.python.org/3/library/typing.html#typing.Protocol

For the simple example here it goes like this:

from typing import Protocol

class MyShowProto(Protocol):
    def show(self):
        ...


class MyClass:
    def show(self):
        print('Hello World!')


class MyOtherClass:
    pass


def foo(o: MyShowProto):
    return o.show()

foo(MyClass())  # ok
foo(MyOtherClass())  # fails

foo(MyOtherClass()) will fail static type checks:

$ mypy proto-experiment.py 
proto-experiment.py:21: error: Argument 1 to "foo" has incompatible type "MyOtherClass"; expected "MyShowProto"
Found 1 error in 1 file (checked 1 source file)

In addition, you can specify the base class explicitly, for instance:

class MyOtherClass(MyShowProto):

but note that this makes methods of the base class actually available on the subclass, and thus the static checker will not report that a method definition is missing on the MyOtherClass. So in this case, in order to get a useful type-checking, all the methods that we want to be explicitly implemented should be decorated with @abstractmethod:

from typing import Protocol
from abc import abstractmethod

class MyShowProto(Protocol):
    @abstractmethod
    def show(self): raise NotImplementedError


class MyOtherClass(MyShowProto):
    pass


MyOtherClass()  # error in type checker

How do I know which version of Javascript I'm using?

JavaScript 1.2 was introduced with Netscape Navigator 4 in 1997. That version number only ever had significance for Netscape browsers. For example, Microsoft's implementation (as used in Internet Explorer) is called JScript, and has its own version numbering which bears no relation to Netscape's numbering.

The value violated the integrity constraints for the column

Teradata table or view stores NULL as "?" and SQL considers it as a character or string. This is the main reason for the error "The value violated the integrity constraints for the column." when data is ported from Teradata source to SQL destination. Solution 1: Allow the destination table to hold NULL Solution 2: Convert the '?' character to be stored as some value in the destination table.

When to use Spring Security`s antMatcher()?

You need antMatcher for multiple HttpSecurity, see Spring Security Reference:

5.7 Multiple HttpSecurity

We can configure multiple HttpSecurity instances just as we can have multiple <http> blocks. The key is to extend the WebSecurityConfigurationAdapter multiple times. For example, the following is an example of having a different configuration for URL’s that start with /api/.

@EnableWebSecurity
public class MultiHttpSecurityConfig {
  @Autowired
  public void configureGlobal(AuthenticationManagerBuilder auth) { 1
      auth
          .inMemoryAuthentication()
              .withUser("user").password("password").roles("USER").and()
              .withUser("admin").password("password").roles("USER", "ADMIN");
  }

  @Configuration
  @Order(1)                                                        2
  public static class ApiWebSecurityConfigurationAdapter extends WebSecurityConfigurerAdapter {
      protected void configure(HttpSecurity http) throws Exception {
          http
              .antMatcher("/api/**")                               3
              .authorizeRequests()
                  .anyRequest().hasRole("ADMIN")
                  .and()
              .httpBasic();
      }
  }    

  @Configuration                                                   4
  public static class FormLoginWebSecurityConfigurerAdapter extends WebSecurityConfigurerAdapter {

      @Override
      protected void configure(HttpSecurity http) throws Exception {
          http
              .authorizeRequests()
                  .anyRequest().authenticated()
                  .and()
              .formLogin();
      }
  }
}

1 Configure Authentication as normal

2 Create an instance of WebSecurityConfigurerAdapter that contains @Order to specify which WebSecurityConfigurerAdapter should be considered first.

3 The http.antMatcher states that this HttpSecurity will only be applicable to URLs that start with /api/

4 Create another instance of WebSecurityConfigurerAdapter. If the URL does not start with /api/ this configuration will be used. This configuration is considered after ApiWebSecurityConfigurationAdapter since it has an @Order value after 1 (no @Order defaults to last).

In your case you need no antMatcher, because you have only one configuration. Your modified code:

http
    .authorizeRequests()
        .antMatchers("/high_level_url_A/sub_level_1").hasRole('USER')
        .antMatchers("/high_level_url_A/sub_level_2").hasRole('USER2')
        .somethingElse() // for /high_level_url_A/**
        .antMatchers("/high_level_url_A/**").authenticated()
        .antMatchers("/high_level_url_B/sub_level_1").permitAll()
        .antMatchers("/high_level_url_B/sub_level_2").hasRole('USER3')
        .somethingElse() // for /high_level_url_B/**
        .antMatchers("/high_level_url_B/**").authenticated()
        .anyRequest().permitAll()

How to subscribe to an event on a service in Angular2?

Using alpha 28, I accomplished programmatically subscribing to event emitters by way of the eventEmitter.toRx().subscribe(..) method. As it is not intuitive, it may perhaps change in a future release.

Bulk Record Update with SQL

Your approach is OK

Maybe slightly clearer (to me anyway!)

UPDATE
  T1
SET
  [Description] = t2.[Description]
FROM
   Table1 T1
   JOIN
   [Table2] t2 ON t2.[ID] = t1.DescriptionID

Both this and your query should run the same performance wise because it is the same query, just laid out differently.

error LNK2038: mismatch detected for '_ITERATOR_DEBUG_LEVEL': value '0' doesn't match value '2' in main.obj

Try this: Goto project property -> C/C++ -> Code generation -> Runtime Library Select from combobox value : Multi-threaded DLL (/MD) It work for me :)

Install specific branch from github using Npm

I'm using SSH to authenticate my GitHub account and have a couple dependencies in my project installed as follows:

"dependencies": {
  "<dependency name>": "git+ssh://[email protected]/<github username>/<repository name>.git#<release version | branch>"
}

Flask - Calling python function on button OnClick event

Easiest solution

<button type="button" onclick="window.location.href='{{ url_for( 'move_forward') }}';">Forward</button>

Display all dataframe columns in a Jupyter Python Notebook

I know this question is a little old but the following worked for me in a Jupyter Notebook running pandas 0.22.0 and Python 3:

import pandas as pd
pd.set_option('display.max_columns', <number of columns>)

You can do the same for the rows too:

pd.set_option('display.max_rows', <number of rows>)

This saves importing IPython, and there are more options in the pandas.set_option documentation: https://pandas.pydata.org/pandas-docs/stable/reference/api/pandas.set_option.html

How get the base URL via context path in JSF?

URLs are not resolved based on the file structure in the server side. URLs are resolved based on the real public web addresses of the resources in question. It's namely the webbrowser who has got to invoke them, not the webserver.

There are several ways to soften the pain:

JSF EL offers a shorthand to ${pageContext.request} in flavor of #{request}:

<li><a href="#{request.contextPath}/index.xhtml">Home</a></li>
<li><a href="#{request.contextPath}/about_us.xhtml">About us</a></li>

You can if necessary use <c:set> tag to make it yet shorter. Put it somewhere in the master template, it'll be available to all pages:

<c:set var="root" value="#{request.contextPath}/" />
...
<li><a href="#{root}index.xhtml">Home</a></li>
<li><a href="#{root}about_us.xhtml">About us</a></li>

JSF 2.x offers the <h:link> which can take a view ID relative to the context root in outcome and it will append the context path and FacesServlet mapping automatically:

<li><h:link value="Home" outcome="index" /></li>
<li><h:link value="About us" outcome="about_us" /></li>

HTML offers the <base> tag which makes all relative URLs in the document relative to this base. You could make use of it. Put it in the <h:head>.

<base href="#{request.requestURL.substring(0, request.requestURL.length() - request.requestURI.length())}#{request.contextPath}/" />
...
<li><a href="index.xhtml">Home</a></li>
<li><a href="about_us.xhtml">About us</a></li>

(note: this requires EL 2.2, otherwise you'd better use JSTL fn:substring(), see also this answer)

This should end up in the generated HTML something like as

<base href="http://example.com/webname/" />

Note that the <base> tag has a caveat: it makes all jump anchors in the page like <a href="#top"> relative to it as well! See also Is it recommended to use the <base> html tag? In JSF you could solve it like <a href="#{request.requestURI}#top">top</a> or <h:link value="top" fragment="top" />.

SQL WHERE ID IN (id1, id2, ..., idn)

In most database systems, IN (val1, val2, …) and a series of OR are optimized to the same plan.

The third way would be importing the list of values into a temporary table and join it which is more efficient in most systems, if there are lots of values.

You may want to read this articles:

How to create exe of a console application

an EXE file is created as long as you build the project. you can usually find this on the debug folder of you project.

C:\Users\username\Documents\Visual Studio 2012\Projects\ProjectName\bin\Debug

How to get the number of threads in a Java process

There is a static method on the Thread Class that will return the number of active threads controlled by the JVM:

Thread.activeCount()

Returns the number of active threads in the current thread's thread group.

Additionally, external debuggers should list all active threads (and allow you to suspend any number of them) if you wish to monitor them in real-time.

What's the difference between primitive and reference types?

The short answer is primitives are data types, while references are pointers, which do not hold their values but point to their values and are used on/with objects.

Primatives:

boolean

character

byte

short

integer

long

float

double

Lots of good references that explain these basic concepts. http://www.javaforstudents.co.uk/Types

How to draw polygons on an HTML5 canvas?

from http://www.scienceprimer.com/drawing-regular-polygons-javascript-canvas:

The following code will draw a hexagon. Change the number of sides to create different regular polygons.

_x000D_
_x000D_
var ctx = document.getElementById('hexagon').getContext('2d');_x000D_
_x000D_
// hexagon_x000D_
var numberOfSides = 6,_x000D_
    size = 20,_x000D_
    Xcenter = 25,_x000D_
    Ycenter = 25;_x000D_
_x000D_
ctx.beginPath();_x000D_
ctx.moveTo (Xcenter +  size * Math.cos(0), Ycenter +  size *  Math.sin(0));          _x000D_
_x000D_
for (var i = 1; i <= numberOfSides;i += 1) {_x000D_
  ctx.lineTo (Xcenter + size * Math.cos(i * 2 * Math.PI / numberOfSides), Ycenter + size * Math.sin(i * 2 * Math.PI / numberOfSides));_x000D_
}_x000D_
_x000D_
ctx.strokeStyle = "#000000";_x000D_
ctx.lineWidth = 1;_x000D_
ctx.stroke();
_x000D_
#hexagon { border: thin dashed red; }
_x000D_
<canvas id="hexagon"></canvas>
_x000D_
_x000D_
_x000D_

How do I update a Linq to SQL dbml file?

I would recommend using the visual designer built into VS2008, as updating the dbml also updates the code that is generated for you. Modifying the dbml outside of the visual designer would result in the underlying code being out of sync.