VS 2017 Metadata file '.dll could not be found
I had the same problem, even with no other errors showing on the "Error List" view after "Rebuild Solution". However, on the "Output" view, I saw the error that was behind the issue:
The primary reference "C:...\myproj.dll" could not be resolved because it was built against the ".NETFramework,Version=v4.6.1" framework. This is a higher version than the currently targeted framework ".NETFramework,Version=v4.5"
Once I corrected this, the issue was resolved.
Visual Studio 2017 errors on standard headers
This problem may also happen if you have a unit test project that has a different C++ version than the project you want to test.
Example:
- EXE with C++ 17 enabled explicitly
- Unit Test with C++ version set to "Default"
Solution: change the Unit Test to C++17 as well.
TypeError: list indices must be integers or slices, not str
I had same error and the mistake was that I had added list and dictionary into the same list (object) and when I used to iterate over the list of dictionaries and use to hit a list (type) object then I used to get this error.
Its was a code error and made sure that I only added dictionary objects to that list and list typed object into the list, this solved my issue as well.
How to include js and CSS in JSP with spring MVC
Put your style.css directly into the webapp/css folder, not into the WEB-INF folder.
Then add the following code into your spring-dispatcher-servlet.xml
<mvc:resources mapping="/css/**" location="/css/" />
and then add following code into your jsp page
<link rel="stylesheet" type="text/css" href="css/style.css"/>
I hope it will work.
reading external sql script in python
according me, it is not possible
solution:
import .sql file on mysql server
after
import mysql.connector
import pandas as pd
and then you use .sql file by convert to dataframe
Play sound on button click android
there are some predefined sounds: SHUTTER_CLICK, FOCUS_COMPLETE, START_VIDEO_RECORDING, STOP_VIDEO_RECORDING.
Nice!
MediaActionSound
A class for producing sounds that match those produced by various actions taken by the media and camera APIs. Docs
use like:
fun playBeepSound() {
val sound = MediaActionSound()
sound.play(MediaActionSound.START_VIDEO_RECORDING)
}
Find duplicate values in R
This will give you duplicate rows:
vocabulary[duplicated(vocabulary$id),]
This will give you the number of duplicates:
dim(vocabulary[duplicated(vocabulary$id),])[1]
Example:
vocabulary2 <-rbind(vocabulary,vocabulary[1,]) #creates a duplicate at the end
vocabulary2[duplicated(vocabulary2$id),]
# id year sex education vocabulary
#21639 20040001 2004 Female 9 3
dim(vocabulary2[duplicated(vocabulary2$id),])[1]
#[1] 1 #=1 duplicate
EDIT
OK, with the additional information, here's what you should do: duplicated has a fromLast option which allows you to get duplicates from the end. If you combine this with the normal duplicated, you get all duplicates. The following example adds duplicates to the original vocabulary object (line 1 is duplicated twice and line 5 is duplicated once). I then use table to get the total number of duplicates per ID.
#Create vocabulary object with duplicates
voc.dups <-rbind(vocabulary,vocabulary[1,],vocabulary[1,],vocabulary[5,])
#List duplicates
dups <-voc.dups[duplicated(voc.dups$id)|duplicated(voc.dups$id, fromLast=TRUE),]
dups
# id year sex education vocabulary
#1 20040001 2004 Female 9 3
#5 20040008 2004 Male 14 1
#21639 20040001 2004 Female 9 3
#21640 20040001 2004 Female 9 3
#51000 20040008 2004 Male 14 1
#Count duplicates by id
table(dups$id)
#20040001 20040008
# 3 2
Wait .5 seconds before continuing code VB.net
I've had better results by checking the browsers readystate before continuing to the next step. This will do nothing until the browser is has a "complete" readystate
Do While WebBrowser1.ReadyState <> 4
''' put anything here.
Loop
Update label from another thread
You cannot update UI from any other thread other than the UI thread.
Use this to update thread on the UI thread.
private void AggiornaContatore()
{
if(this.lblCounter.InvokeRequired)
{
this.lblCounter.BeginInvoke((MethodInvoker) delegate() {this.lblCounter.Text = this.index.ToString(); ;});
}
else
{
this.lblCounter.Text = this.index.ToString(); ;
}
}
Please go through this chapter and more from this book to get a clear picture about threading:
http://www.albahari.com/threading/part2.aspx#_Rich_Client_Applications
How to change TIMEZONE for a java.util.Calendar/Date
The class Date/Timestamp represents a specific instant in time, with millisecond precision, since January 1, 1970, 00:00:00 GMT. So this time difference (from epoch to current time) will be same in all computers across the world with irrespective of Timezone.
Date/Timestamp doesn't know about the given time is on which timezone.
If we want the time based on timezone we should go for the Calendar or SimpleDateFormat classes in java.
If you try to print a Date/Timestamp object using toString(), it will convert and print the time with the default timezone of your machine.
So we can say (Date/Timestamp).getTime() object will always have UTC (time in milliseconds)
To conclude Date.getTime() will give UTC time, but toString() is on locale specific timezone, not UTC.
Now how will I create/change time on specified timezone?
The below code gives you a date (time in milliseconds) with specified timezones. The only problem here is you have to give date in string format.
DateFormat dateFormat = new SimpleDateFormat("yyyyMMdd HH:mm:ss");
dateFormatLocal.setTimeZone(timeZone);
java.util.Date parsedDate = dateFormatLocal.parse(date);
Use dateFormat.format for taking input Date (which is always UTC), timezone and return date as String.
How to store UTC/GMT time in DB:
If you print the parsedDate object, the time will be in default timezone.
But you can store the UTC time in DB like below.
Calendar calGMT = Calendar.getInstance(TimeZone.getTimeZone("GMT"));
Timestamp tsSchedStartTime = new Timestamp (parsedDate.getTime());
if (tsSchedStartTime != null) {
stmt.setTimestamp(11, tsSchedStartTime, calGMT );
} else {
stmt.setNull(11, java.sql.Types.DATE);
}
PHP Fatal error: Call to undefined function mssql_connect()
php.ini probably needs to read:
extension=ext\php_sqlsrv_53_nts.dll
Or move the file to same directory as the php executable. This is what I did to my php5 install this week to get odbc_pdo working. :P
Additionally, that doesn't look like proper phpinfo() output. If you make a file with contents
<? phpinfo(); ?> and visit that page, the HTML output should show several sections, including one with loaded modules. (Edited to add: like shown in the screenshot of the above accepted answer)
Spring JDBC Template for calling Stored Procedures
There are a number of ways to call stored procedures in Spring.
If you use CallableStatementCreator to declare parameters, you will be using Java's standard interface of CallableStatement, i.e register out parameters and set them separately. Using SqlParameter abstraction will make your code cleaner.
I recommend you looking at SimpleJdbcCall. It may be used like this:
SimpleJdbcCall jdbcCall = new SimpleJdbcCall(jdbcTemplate)
.withSchemaName(schema)
.withCatalogName(package)
.withProcedureName(procedure)();
...
jdbcCall.addDeclaredParameter(new SqlParameter(paramName, OracleTypes.NUMBER));
...
jdbcCall.execute(callParams);
For simple procedures you may use jdbcTemplate's update method:
jdbcTemplate.update("call SOME_PROC (?, ?)", param1, param2);
ASP.NET strange compilation error
The answers provided are not the solution. The .NET 6# stuff is pretty different from what we used to. A lot has changed, from having to deal with portable libraries to Visual Studio 2015 installing an old compiler (it cost me four hours cracking my head).
The long story short: Stack Overflow question How do I use C# 6 with a Web Site project type?
You need to install the C# .NET compiler (now runs as a service bla bla bla).
and you need to run updates on NuGet to get the latest everything (before trying anything else).
The compiler must be installed on the project your solution runs from (so your website or your main project your application starts from (if you have multiple projects)).
Once you install that then sort out your web.config referencing any portable libraries, and delete both the bin and obj folder (to avoid works on my computer nightmare), It should just run. But be patient; what happens on your machine may vary as much as the answers above. Most of the answers above hide other problems. It may work for a while, then boom: compiler error. I had a few pages working, then some pages started failing because of some packages that have started using portable libraries.
How to clone an InputStream?
Cloning an input stream might not be a good idea, because this requires deep knowledge about the details of the input stream being cloned. A workaround for this is to create a new input stream that reads from the same source again.
So using some Java 8 features this would look like this:
public class Foo {
private Supplier<InputStream> inputStreamSupplier;
public void bar() {
procesDataThisWay(inputStreamSupplier.get());
procesDataTheOtherWay(inputStreamSupplier.get());
}
private void procesDataThisWay(InputStream) {
// ...
}
private void procesDataTheOtherWay(InputStream) {
// ...
}
}
This method has the positive effect that it will reuse code that is already in place - the creation of the input stream encapsulated in inputStreamSupplier. And there is no need to maintain a second code path for the cloning of the stream.
On the other hand, if reading from the stream is expensive (because a it's done over a low bandwith connection), then this method will double the costs. This could be circumvented by using a specific supplier that will store the stream content locally first and provide an InputStream for that now local resource.
How do I show a console output/window in a forms application?
this one should work.
using System.Runtime.InteropServices;
private void Form1_Load(object sender, EventArgs e)
{
AllocConsole();
}
[DllImport("kernel32.dll", SetLastError = true)]
[return: MarshalAs(UnmanagedType.Bool)]
static extern bool AllocConsole();
Return multiple values in JavaScript?
I am nothing adding new here but another alternate way.
var newCodes = function() {
var dCodes = fg.codecsCodes.rs;
var dCodes2 = fg.codecsCodes2.rs;
let [...val] = [dCodes,dCodes2];
return [...val];
};
Can I pass an argument to a VBScript (vbs file launched with cscript)?
You can use WScript.Arguments to access the arguments passed to your script.
Calling the script:
cscript.exe test.vbs "C:\temp\"
Inside your script:
Set File = FSO.OpenTextFile(WScript.Arguments(0) &"\test.txt", 2, True)
Don't forget to check if there actually has been an argument passed to your script. You can do so by checking the Count property:
if WScript.Arguments.Count = 0 then
WScript.Echo "Missing parameters"
end if
If your script is over after you close the file then there is no need to set the variables to Nothing. The resources will be cleaned up automatically when the cscript.exe process terminates. Setting a variable to Nothing usually is only necessary if you explicitly want to free resources during the execution of your script. In that case, you would set variables which contain a reference to a COM object to Nothing, which would release the COM object before your script terminates. This is just a short answer to your bonus question, you will find more information in these related questions:
Is there a need to set Objects to Nothing inside VBA Functions
When must I set a variable to “Nothing” in VB6?
While loop in batch
A while loop can be simulated in cmd.exe with:
:still_more_files
if %countfiles% leq 21 (
rem change countfile here
goto :still_more_files
)
For example, the following script:
@echo off
setlocal enableextensions enabledelayedexpansion
set /a "x = 0"
:more_to_process
if %x% leq 5 (
echo %x%
set /a "x = x + 1"
goto :more_to_process
)
endlocal
outputs:
0
1
2
3
4
5
For your particular case, I would start with the following. Your initial description was a little confusing. I'm assuming you want to delete files in that directory until there's 20 or less:
@echo off
set backupdir=c:\test
:more_files_to_process
for /f %%x in ('dir %backupdir% /b ^| find /v /c "::"') do set num=%%x
if %num% gtr 20 (
cscript /nologo c:\deletefile.vbs %backupdir%
goto :more_files_to_process
)
Metadata file '.dll' could not be found
For me it occurred when I included a new project to a solution.
Visual Studio automatically selects .NET framework 4.5.
I changed to version .NET 4.5.2 like the other libraries, and it worked.
Javascript Confirm popup Yes, No button instead of OK and Cancel
1) You can download and upload below files on your site
<link href="/Style%20Library/css/smoothness/jquery.alerts.css" type="text/css" rel="stylesheet"/>
2) after that you can directly use below code
$.alerts.okButton = "yes";
$.alerts.cancelButton = "no";
in document.ready function.
Please try it will work.
Thanks
Collection was modified; enumeration operation may not execute
There is one link where it elaborated very well & solution is also given.
Try it if you got proper solution please post here so other can understand.
Given solution is ok then like the post so other can try these solution.
for you reference original link :-
https://bensonxion.wordpress.com/2012/05/07/serializing-an-ienumerable-produces-collection-was-modified-enumeration-operation-may-not-execute/
When we use .Net Serialization classes to serialize an object where its definition contains an Enumerable type, i.e.
collection, you will be easily getting InvalidOperationException saying "Collection was modified;
enumeration operation may not execute" where your coding is under multi-thread scenarios.
The bottom cause is that serialization classes will iterate through collection via enumerator, as such,
problem goes to trying to iterate through a collection while modifying it.
First solution, we can simply use lock as a synchronization solution to ensure that
the operation to the List object can only be executed from one thread at a time.
Obviously, you will get performance penalty that
if you want to serialize a collection of that object, then for each of them, the lock will be applied.
Well, .Net 4.0 which makes dealing with multi-threading scenarios handy.
for this serializing Collection field problem, I found we can just take benefit from ConcurrentQueue(Check MSDN)class,
which is a thread-safe and FIFO collection and makes code lock-free.
Using this class, in its simplicity, the stuff you need to modify for your code are replacing Collection type with it,
use Enqueue to add an element to the end of ConcurrentQueue, remove those lock code.
Or, if the scenario you are working on do require collection stuff like List, you will need a few more code to adapt ConcurrentQueue into your fields.
BTW, ConcurrentQueue doesnât have a Clear method due to underlying algorithm which doesnât permit atomically clearing of the collection.
so you have to do it yourself, the fastest way is to re-create a new empty ConcurrentQueue for a replacement.
Can I get "&&" or "-and" to work in PowerShell?
I think a simple if statement can accomplish this. Once I saw mkelement0's response that the last exit status is stored in $?, I put the following together:
# Set the first command to a variable
$a=somecommand
# Temporary variable to store exit status of the last command (since we can't write to "$?")
$test=$?
# Run the test
if ($test=$true) { 2nd-command }
So for the OP's example, it would be:
a=(csc /t:exe /out:a.exe SomeFile.cs); $test = $?; if ($test=$true) { a.exe }
How can I format a String number to have commas and round?
You might want to look at the DecimalFormat class; it supports different locales (eg: in some countries that would get formatted as 1.000.500.000,57 instead).
You also need to convert that string into a number, this can be done with:
double amount = Double.parseDouble(number);
Code sample:
String number = "1000500000.574";
double amount = Double.parseDouble(number);
DecimalFormat formatter = new DecimalFormat("#,###.00");
System.out.println(formatter.format(amount));
Calculating Waiting Time and Turnaround Time in (non-preemptive) FCFS queue
For non-preemptive system,
waitingTime = startTime - arrivalTime
turnaroundTime = burstTime + waitingTime = finishTime- arrivalTime
startTime = Time at which the process started executing
finishTime = Time at which the process finished executing
You can keep track of the current time elapsed in the system(timeElapsed). Assign all processors to a process in the beginning, and execute until the shortest process is done executing. Then assign this processor which is free to the next process in the queue. Do this until the queue is empty and all processes are done executing. Also, whenever a process starts executing, recored its startTime, when finishes, record its finishTime (both same as timeElapsed). That way you can calculate what you need.
How to post SOAP Request from PHP
I needed to do many very simple XML requests and after reading @Ivan Krechetov's comment about the speed hit of SOAP, I tried his code and discovered http_post_data() is not built into PHP 5.2. Not really wanting to install it, I tried cURL which is on all my servers. Although I do not know how fast cURL is compared to SOAP, it sure was easy to do what I needed. Below is a sample with cURL for anyone needing it.
$xml_data = '<?xml version="1.0" encoding="UTF-8" ?>
<priceRequest><customerNo>123</customerNo><password>abc</password><skuList><SKU>99999</SKU><lineNumber>1</lineNumber></skuList></priceRequest>';
$URL = "https://test.testserver.com/PriceAvailability";
$ch = curl_init($URL);
curl_setopt($ch, CURLOPT_HTTPHEADER, array('Content-Type: text/xml'));
curl_setopt($ch, CURLOPT_POST, 1);
curl_setopt($ch, CURLOPT_POSTFIELDS, "$xml_data");
curl_setopt($ch, CURLOPT_RETURNTRANSFER, 1);
$output = curl_exec($ch);
curl_close($ch);
print_r($output);
How to select lines between two marker patterns which may occur multiple times with awk/sed
I tried to use awk to print lines between two patterns while pattern2 also match pattern1. And the pattern1 line should also be printed.
e.g.
source
package AAA
aaa
bbb
ccc
package BBB
ddd
eee
package CCC
fff
ggg
hhh
iii
package DDD
jjj
should has an ouput of
package BBB
ddd
eee
Where pattern1 is package BBB, pattern2 is package \w*. Note that CCC isn't a known value so can't be literally matched.
In this case, neither @scai 's awk '/abc/{a=1}/mno/{print;a=0}a' file nor @fedorqui 's awk '/abc/{a=1} a; /mno/{a=0}' file works for me.
Finally, I managed to solve it by awk '/package BBB/{flag=1;print;next}/package \w*/{flag=0}flag' file, haha
A little more effort result in awk '/package BBB/{flag=1;print;next}flag;/package \w*/{flag=0}' file, to print pattern2 line also, that is,
package BBB
ddd
eee
package CCC
How can I permanently enable line numbers in IntelliJ?
I add this response for IntelliJ IDEA 2018.2 - Ultimate.
Using menu
IntelliJ Idea > Preferences > Editor > General > Appearance > Show Line Numbers
Using Shortcuts - First way
For Windows : Ctrl+Shift+a
For Mac : Cmd+shift+a
Using Shortcuts - Seconde way
Touch Shift twice
These three methods exist since the last 4 versions of Intellij and I think they remain valid for a long time.
SQL - using alias in Group By
I'm not answering why it is so, but only wanted to show a way around that limitation in SQL Server by using CROSS APPLY to create the alias. You then use it in the GROUP BY clause, like so:
SELECT
itemName as ItemName,
FirstLetter,
Count(itemName)
FROM table1
CROSS APPLY (SELECT substring(itemName, 1,1) as FirstLetter) Alias
GROUP BY itemName, FirstLetter
What's the actual use of 'fail' in JUnit test case?
The most important use case is probably exception checking.
While junit4 includes the expected element for checking if an exception occurred, it seems like it isn't part of the newer junit5. Another advantage of using fail() over the expected is that you can combine it with finally allowing test-case cleanup.
dao.insert(obj);
try {
dao.insert(obj);
fail("No DuplicateKeyException thrown.");
} catch (DuplicateKeyException e) {
assertEquals("Error code doesn't match", 123, e.getErrorCode());
} finally {
//cleanup
dao.delete(obj);
}
As noted in another comment. Having a test to fail until you can finish implementing it sounds reasonable as well.
explode string in jquery
The split method will create an array. So you need to access the third element in your case..
(arrays are 0-indexed) You need to access result[2] to get the url
var result = $(row).text().split('|');
alert( result[2] );
You do not give us enough information to know what row is, exactly.. So depending on how you acquire the variable row you might need to do one of the following.
- if
row is a string then row.split('|');
- if it is a DOM element then
$(row).text().split('|');
- if it is an
input element then $(row).val().split('|');
Downloading folders from aws s3, cp or sync?
Using aws s3 cp from the AWS Command-Line Interface (CLI) will require the --recursive parameter to copy multiple files.
aws s3 cp s3://myBucket/dir localdir --recursive
The aws s3 sync command will, by default, copy a whole directory. It will only copy new/modified files.
aws s3 sync s3://mybucket/dir localdir
Just experiment to get the result you want.
Documentation:
How to disable the ability to select in a DataGridView?
I'd go with this:
private void myDataGridView_SelectionChanged(Object sender, EventArgs e)
{
dgvSomeDataGridView.ClearSelection();
}
I don't agree with the broad assertion that no DataGridView should be unselectable. Some UIs are built for tools or touchsreens, and allowing a selection misleads the user to think that selecting will actually get them somewhere.
Setting ReadOnly = true on the control has no impact on whether a cell or row can be selected. And there are visual and functional downsides to setting Enabled = false.
Another option is to set the control selected colors to be exactly what the non-selected colors are, but if you happen to be manipulating the back color of the cell, then this method yields some nasty results as well.
How to keep a Python script output window open?
I found the solution on my py3 enviroment at win10 is just run cmd or powershell as Administrator,and the output would stay at the same console window,any other type of user run python command would cause python to open a new console window.
Dynamically updating css in Angular 2
Try this
<div class="home-component"
[style.width.px]="width"
[style.height.px]="height">Some stuff in this div</div>
[Updated]:
To set in % use
[style.height.%]="height">Some stuff in this div</div>
Enabling WiFi on Android Emulator
Apparently it does not and I didn't quite expect it would. HOWEVER Ivan brings up a good possibility that has escaped Android people.
What is the purpose of an emulator? to EMULATE, right? I don't see why for testing purposes -provided the tester understands the limitations- the emulator might not add a Wifi emulator.
It could for example emulate WiFi access by using the underlying internet connection of the host. Obviously testing WPA/WEP differencess would not make sense but at least it could toggle access via WiFi.
Or some sort of emulator plugin where there would be a base WiFi emulator that would emulate WiFi access via the underlying connection but then via configuration it could emulate WPA/WEP by providing a list of fake WiFi networks and their corresponding fake passwords that would be matched against a configurable list of credentials.
After all the idea is to do initial testing on the emulator and then move on to the actual device.
css3 text-shadow in IE9
As IE9 does not support CSS3 text-shadow, I would just use the filter property for IE instead. Live example: http://jsfiddle.net/dmM2S/
text-shadow:1px 1px 1px red; /* CSS3 */
can be replaced with
filter: Shadow(Color=red, Direction=130, Strength=1); /* IE Proprietary Filter*/
You can get the results to be very similar.
Single Line Nested For Loops
First of all, your first code doesn't use a for loop per se, but a list comprehension.
Would be equivalent to
for j in range(0, width):
for i in range(0, height):
m[i][j]
Much the same way, it generally nests like for loops, right to left. But list comprehension syntax is more complex.
I'm not sure what this question is asking
Any iterable object that yields iterable objects that yield exactly two objects (what a mouthful - i.e [(1,2),'ab'] would be valid )
The order in which the object yields upon iteration. i goes to the first yield, j the second.
Yes, but not as pretty. I believe it is functionally equivalent to:
l = list()
for i,j in object:
l.append(function(i,j))
or even better use map:
map(function, object)
But of course function would have to get i, j itself.
Isn't this the same question as 3?
Vlookup referring to table data in a different sheet
One of the common problems with VLOOKUP is "data mismatch" where #N/A is returned because a numeric lookup value doesn't match a text-formatted value in the VLOOKUP table (or vice versa)
Does either of these versions work?
=VLOOKUP(M3&"",Sheet1!$A$2:$Q$47,13,FALSE)
or
=VLOOKUP(M3+0,Sheet1!$A$2:$Q$47,13,FALSE)
The former converts a numeric lookup value to text (assuming that lookup table 1st column contains numbers formatted as text). The latter does the reverse, changing a text-formatted lookup value to a number.
Depending on which one works (assuming one does) then you may want to permanently change the format of your data so that the standard VLOOKUP will work
XMLHttpRequest status 0 (responseText is empty)
The cause of your problems is that you are trying to do a cross-domain call and it fails.
If you're doing localhost development you can make cross-domain calls - I do it all the time.
For Firefox, you have to enable it in your config settings
signed.applets.codebase_principal_support = true
Then add something like this to your XHR open code:
if (isLocalHost()){
if (typeof(netscape) != 'undefined' && typeof(netscape.security) != 'undefined'){
netscape.security.PrivilegeManager.enablePrivilege('UniversalBrowserRead');
}
}
For IE, if I remember right, all you have to do is enable the browser's Security setting under "Miscellaneous → Access data sources across domains" to get it to work with ActiveX XHRs.
IE8 and above also added cross-domain capabilities to the native XmlHttpRequest objects, but I haven't played with those yet.
How to concatenate multiple lines of output to one line?
Here is another simple method using awk:
# cat > file.txt
a
b
c
# cat file.txt | awk '{ printf("%s ", $0) }'
a b c
Also, if your file has columns, this gives an easy way to concatenate only certain columns:
# cat > cols.txt
a b c
d e f
# cat cols.txt | awk '{ printf("%s ", $2) }'
b e
Differences between ConstraintLayout and RelativeLayout
Intention of ConstraintLayout is to optimize and flatten the view hierarchy of your layouts by applying some rules to each view to avoid nesting.
Rules remind you of RelativeLayout, for example setting the left to the left of some other view.
app:layout_constraintBottom_toBottomOf="@+id/view1"
Unlike RelativeLayout, ConstraintLayout offers bias value that is used to position a view in terms of 0% and 100% horizontal and vertical offset relative to the handles (marked with circle). These percentages (and fractions) offer seamless positioning of the view across different screen densities and sizes.
app:layout_constraintHorizontal_bias="0.33" <!-- from 0.0 to 1.0 -->
app:layout_constraintVertical_bias="0.53" <!-- from 0.0 to 1.0 -->
Baseline handle (long pipe with rounded corners, below the circle handle) is used to align content of the view with another view reference.
Square handles (on each corner of the view) are used to resize the view in dps.
This is totally opinion based and my impression of ConstraintLayout
nodejs - How to read and output jpg image?
Here is how you can read the entire file contents, and if done successfully, start a webserver which displays the JPG image in response to every request:
var http = require('http')
var fs = require('fs')
fs.readFile('image.jpg', function(err, data) {
if (err) throw err // Fail if the file can't be read.
http.createServer(function(req, res) {
res.writeHead(200, {'Content-Type': 'image/jpeg'})
res.end(data) // Send the file data to the browser.
}).listen(8124)
console.log('Server running at http://localhost:8124/')
})
Note that the server is launched by the "readFile" callback function and the response header has Content-Type: image/jpeg.
[Edit] You could even embed the image in an HTML page directly by using an <img> with a data URI source. For example:
res.writeHead(200, {'Content-Type': 'text/html'});
res.write('<html><body><img src="data:image/jpeg;base64,')
res.write(Buffer.from(data).toString('base64'));
res.end('"/></body></html>');
Convert a string into an int
I had to do something like this but wanted to use a getter/setter for mine. In particular I wanted to return a long from a textfield. The other answers all worked well also, I just ended up adapting mine a little as my school project evolved.
long ms = [self.textfield.text longLongValue];
return ms;
How can I make an image transparent on Android?
Use:
ImageView image = (ImageView) findViewById(R.id.image);
image.setAlpha(150); // Value: [0-255]. Where 0 is fully transparent
// and 255 is fully opaque. Set the value according
// to your choice, and you can also use seekbar to
// maintain the transparency.
Switch statement multiple cases in JavaScript
I can see there are lots of good answers here, but what happens if we need to check more than 10 cases? Here is my own approach:
function isAccessible(varName){
let accessDenied = ['Liam', 'Noah', 'William', 'James', 'Logan', 'Benjamin',
'Mason', 'Elijah', 'Oliver', 'Jacob', 'Daniel', 'Lucas'];
switch (varName) {
case (accessDenied.includes(varName) ? varName : null):
return 'Access Denied!';
default:
return 'Access Allowed.';
}
}
console.log(isAccessible('Liam'));
Python Database connection Close
You can define a DB class as below. Also, as andrewf suggested, use a context manager for cursor access.I'd define it as a member function.
This way it keeps the connection open across multiple transactions from the app code and saves unnecessary reconnections to the server.
import pyodbc
class MS_DB():
""" Collection of helper methods to query the MS SQL Server database.
"""
def __init__(self, username, password, host, port=1433, initial_db='dev_db'):
self.username = username
self._password = password
self.host = host
self.port = str(port)
self.db = initial_db
conn_str = 'DRIVER=DRIVER=ODBC Driver 13 for SQL Server;SERVER='+ \
self.host + ';PORT='+ self.port +';DATABASE='+ \
self.db +';UID='+ self.username +';PWD='+ \
self._password +';'
print('Connected to DB:', conn_str)
self._connection = pyodbc.connect(conn_str)
pyodbc.pooling = False
def __repr__(self):
return f"MS-SQLServer('{self.username}', <password hidden>, '{self.host}', '{self.port}', '{self.db}')"
def __str__(self):
return f"MS-SQLServer Module for STP on {self.host}"
def __del__(self):
self._connection.close()
print("Connection closed.")
@contextmanager
def cursor(self, commit: bool = False):
"""
A context manager style of using a DB cursor for database operations.
This function should be used for any database queries or operations that
need to be done.
:param commit:
A boolean value that says whether to commit any database changes to the database. Defaults to False.
:type commit: bool
"""
cursor = self._connection.cursor()
try:
yield cursor
except pyodbc.DatabaseError as err:
print("DatabaseError {} ".format(err))
cursor.rollback()
raise err
else:
if commit:
cursor.commit()
finally:
cursor.close()
ms_db = MS_DB(username='my_user', password='my_secret', host='hostname')
with ms_db.cursor() as cursor:
cursor.execute("SELECT @@version;")
print(cur.fetchall())
Why is my CSS bundling not working with a bin deployed MVC4 app?
The CSS and Script bundling should work regardless if .NET is running 4.0 or 4.5. I am running .NET 4.0 and it works fine for me. However in order to get the minification and bundling behavior to work your web.config must be set to not be running in debug mode.
<compilation debug="false" targetFramework="4.0">
Take this bundle for jQuery UI example in the _Layout.cshtml file.
@Styles.Render("~/Content/themes/base/css")
If I run with debug="true" I get the following HTML.
<link href="/Content/themes/base/jquery.ui.core.css" rel="stylesheet"/>
<link href="/Content/themes/base/jquery.ui.resizable.css" rel="stylesheet"/>
<link href="/Content/themes/base/jquery.ui.selectable.css" rel="stylesheet"/>
<link href="/Content/themes/base/jquery.ui.accordion.css" rel="stylesheet"/>
<link href="/Content/themes/base/jquery.ui.autocomplete.css" rel="stylesheet"/>
<link href="/Content/themes/base/jquery.ui.button.css" rel="stylesheet"/>
<link href="/Content/themes/base/jquery.ui.dialog.css" rel="stylesheet"/>
<link href="/Content/themes/base/jquery.ui.slider.css" rel="stylesheet"/>
<link href="/Content/themes/base/jquery.ui.tabs.css" rel="stylesheet"/>
<link href="/Content/themes/base/jquery.ui.datepicker.css" rel="stylesheet"/>
<link href="/Content/themes/base/jquery.ui.progressbar.css" rel="stylesheet"/>
<link href="/Content/themes/base/jquery.ui.theme.css" rel="stylesheet"/>
But if I run with debug="false". I'll get this instead.
<link href="/Content/themes/base/css?v=myqT7npwmF2ABsuSaHqt8SCvK8UFWpRv7T4M8r3kiK01" rel="stylesheet"/>
This is a feature so you can easily debug problems with your Script and CSS files. I'm using the MVC4 RTM.
If you think it might be an MVC dependency problem, I'd recommend going into Nuget and removing all of your MVC related packages, and then search for the Microsoft.AspNet.Mvc package and install it. I'm using the most recent version and it's coming up as v.4.0.20710.0. That should grab all the dependencies you need.
Also if you used to be using MVC3 and are now trying to use MVC4 you'll want to go into your web.config(s) and update their references to point to the 4.0 version of MVC. If you're not sure, you can always create a fresh MVC4 app and copy the web.config from there. Don't forget the web.config in your Views/Areas folders if you do.
UPDATE: I've found that what you need to have is the Nuget package Microsoft.AspNet.Web.Optimization installed in your project. It's included by default in an MVC4 RTM app regardless if you specify the target framework as 4.5 or 4.0. This is the namespace that the bundling classes are included in, and doesn't appear to be dependent on the framework. I've deployed to a server that does not have 4.5 installed and it still works as expected for me. Just make sure the DLL gets deployed with the rest of your app.
How to display an error message in an ASP.NET Web Application
The errors in ASP.Net are saved on the Server.GetLastError property,
Or i would put a label on the asp.net page for displaying the error.
try
{
do something
}
catch (YourException ex)
{
errorLabel.Text = ex.Message;
errorLabel.Visible = true;
}
jquery select option click handler
One possible solution is to add a class to every option
<select name="export_type" id="export_type">
<option class="export_option" value="pdf">PDF</option>
<option class="export_option" value="xlsx">Excel</option>
<option class="export_option" value="docx">DocX</option>
</select>
and then use the click handler for this class
$(document).ready(function () {
$(".export_option").click(function (e) {
//alert('click');
});
});
UPDATE: it looks like the code works in FF, IE and Opera but not in Chrome.
Looking at the specs http://www.w3.org/TR/html401/interact/forms.html#h-17.6 I would say it's a bug in Chrome.
change array size
Yes, it is possible to resize an array. For example:
int[] arr = new int[5];
// increase size to 10
Array.Resize(ref arr, 10);
// decrease size to 3
Array.Resize(ref arr, 3);
If you create an array with CreateInstance() method, the Resize() method is not working. For example:
// create an integer array with size of 5
var arr = Array.CreateInstance(typeof(int), 5);
// this not work
Array.Resize(ref arr, 10);
The array size is not dynamic, even we can resize it. If you want a dynamic array, I think we can use generic List instead.
var list = new List<int>();
// add any item to the list
list.Add(5);
list.Add(8);
list.Add(12);
// we can remove it easily as well
list.Remove(5);
foreach(var item in list)
{
Console.WriteLine(item);
}
Easiest way to convert int to string in C++
Here's another easy way to do
char str[100];
sprintf(str, "%d", 101);
string s = str;
sprintf is a well-known one to insert any data into a string of the required format.
You can convert a char * array to a string as shown in the third line.
transform object to array with lodash
A modern native solution if anyone is interested:
const arr = Object.keys(obj).map(key => ({ key, value: obj[key] }));
or (not IE):
const arr = Object.entries(obj).map(([key, value]) => ({ key, value }));
Strip spaces/tabs/newlines - python
Use the re library
import re
myString = "I want to Remove all white \t spaces, new lines \n and tabs \t"
myString = re.sub(r"[\n\t\s]*", "", myString)
print myString
Output:
IwanttoRemoveallwhitespaces,newlinesandtabs
How to make Java honor the DNS Caching Timeout?
To expand on Byron's answer, I believe you need to edit the file java.security in the %JRE_HOME%\lib\security directory to effect this change.
Here is the relevant section:
#
# The Java-level namelookup cache policy for successful lookups:
#
# any negative value: caching forever
# any positive value: the number of seconds to cache an address for
# zero: do not cache
#
# default value is forever (FOREVER). For security reasons, this
# caching is made forever when a security manager is set. When a security
# manager is not set, the default behavior is to cache for 30 seconds.
#
# NOTE: setting this to anything other than the default value can have
# serious security implications. Do not set it unless
# you are sure you are not exposed to DNS spoofing attack.
#
#networkaddress.cache.ttl=-1
Documentation on the java.security file here.
How to develop or migrate apps for iPhone 5 screen resolution?
You can use this define to calculate if you are using the iPhone 5 based on screen size:
#define IS_IPHONE_5 ( fabs( ( double )[ [ UIScreen mainScreen ] bounds ].size.height - ( double )568 ) < DBL_EPSILON )
then use a simple if statement :
if (IS_IPHONE_5) {
// What ever changes
}
How to make asynchronous HTTP requests in PHP
let me show you my way :)
needs nodejs installed on the server
(my server sends 1000 https get request takes only 2 seconds)
url.php :
<?
$urls = array_fill(0, 100, 'http://google.com/blank.html');
function execinbackground($cmd) {
if (substr(php_uname(), 0, 7) == "Windows"){
pclose(popen("start /B ". $cmd, "r"));
}
else {
exec($cmd . " > /dev/null &");
}
}
fwite(fopen("urls.txt","w"),implode("\n",$urls);
execinbackground("nodejs urlscript.js urls.txt");
// { do your work while get requests being executed.. }
?>
urlscript.js >
var https = require('https');
var url = require('url');
var http = require('http');
var fs = require('fs');
var dosya = process.argv[2];
var logdosya = 'log.txt';
var count=0;
http.globalAgent.maxSockets = 300;
https.globalAgent.maxSockets = 300;
setTimeout(timeout,100000); // maximum execution time (in ms)
function trim(string) {
return string.replace(/^\s*|\s*$/g, '')
}
fs.readFile(process.argv[2], 'utf8', function (err, data) {
if (err) {
throw err;
}
parcala(data);
});
function parcala(data) {
var data = data.split("\n");
count=''+data.length+'-'+data[1];
data.forEach(function (d) {
req(trim(d));
});
/*
fs.unlink(dosya, function d() {
console.log('<%s> file deleted', dosya);
});
*/
}
function req(link) {
var linkinfo = url.parse(link);
if (linkinfo.protocol == 'https:') {
var options = {
host: linkinfo.host,
port: 443,
path: linkinfo.path,
method: 'GET'
};
https.get(options, function(res) {res.on('data', function(d) {});}).on('error', function(e) {console.error(e);});
} else {
var options = {
host: linkinfo.host,
port: 80,
path: linkinfo.path,
method: 'GET'
};
http.get(options, function(res) {res.on('data', function(d) {});}).on('error', function(e) {console.error(e);});
}
}
process.on('exit', onExit);
function onExit() {
log();
}
function timeout()
{
console.log("i am too far gone");process.exit();
}
function log()
{
var fd = fs.openSync(logdosya, 'a+');
fs.writeSync(fd, dosya + '-'+count+'\n');
fs.closeSync(fd);
}
How is using "<%=request.getContextPath()%>" better than "../"
request.getContextPath()- returns root path of your application, while
../ - returns parent directory of a file.
You use request.getContextPath(), as it will always points to root of your application. If you were to move your jsp file from one directory to another, nothing needs to be changed.
Now, consider the second approach. If you were to move your jsp files from one folder to another, you'd have to make changes at every location where you are referring your files.
Also, better approach of using request.getContextPath() will be to set 'request.getContextPath()' in a variable and use that variable for referring your path.
<c:set var="context" value="${pageContext.request.contextPath}" />
<script src="${context}/themes/js/jquery.js"></script>
PS- This is the one reason I can figure out. Don't know if there is any more significance to it.
Change Button color onClick
1.
function setColor(e) {
var target = e.target,
count = +target.dataset.count;
target.style.backgroundColor = count === 1 ? "#7FFF00" : '#FFFFFF';
target.dataset.count = count === 1 ? 0 : 1;
/*
() : ? - this is conditional (ternary) operator - equals
if (count === 1) {
target.style.backgroundColor = "#7FFF00";
target.dataset.count = 0;
} else {
target.style.backgroundColor = "#FFFFFF";
target.dataset.count = 1;
}
target.dataset - return all "data attributes" for current element,
in the form of object,
and you don't need use global variable in order to save the state 0 or 1
*/
}
<input
type="button"
id="button"
value="button"
style="color:white"
onclick="setColor(event)";
data-count="1"
/>
2.
function setColor(e) {
var target = e.target,
status = e.target.classList.contains('active');
e.target.classList.add(status ? 'inactive' : 'active');
e.target.classList.remove(status ? 'active' : 'inactive');
}
.active {
background-color: #7FFF00;
}
.inactive {
background-color: #FFFFFF;
}
<input
type="button"
id="button"
value="button"
style="color:white"
onclick="setColor(event)"
/>
([conditional (ternary) operator])
Example-1
Example-2
Matplotlib 2 Subplots, 1 Colorbar
Using make_axes is even easier and gives a better result. It also provides possibilities to customise the positioning of the colorbar.
Also note the option of subplots to share x and y axes.
import numpy as np
import matplotlib.pyplot as plt
import matplotlib as mpl
fig, axes = plt.subplots(nrows=2, ncols=2, sharex=True, sharey=True)
for ax in axes.flat:
im = ax.imshow(np.random.random((10,10)), vmin=0, vmax=1)
cax,kw = mpl.colorbar.make_axes([ax for ax in axes.flat])
plt.colorbar(im, cax=cax, **kw)
plt.show()
Class has no member named
The reason that the error is occuring is because all the files are not being recognized as being in the same project directory. The easiest way to fix this is to simply create a new project.
File -> Project -> Console application -> Next -> select C or C++ -> Name the project and select the folder to create the project in -> then click finish.
Then to create the class and header files by clicking New -> Class.
Give the class a name and uncheck "Use relative path." Make sure you are creating the class and header file in the same project folder.
After these steps, the left side of the IDE will display the Sources and Headers folders, with main.cpp, theclassname.cpp, and theclassname.h all conviently arranged.
length and length() in Java
Consider:
int[] myArray = new int[10];
String myString = "hello world!";
List<int> myList = new ArrayList<int>();
myArray.length // Gives the length of the array
myString.length() // Gives the length of the string
myList.size() // Gives the length of the list
It's very likely that strings and arrays were designed at different times and hence ended up using different conventions. One justification is that since Strings use arrays internally, a method, length(), was used to avoid duplication of the same information. Another is that using a method length() helps emphasize the immutability of strings, even though the size of an array is also unchangeable.
Ultimately this is just an inconsistency that evolved that would definitely be fixed if the language were ever redesigned from the ground up. As far as I know no other languages (C#, Python, Scala, etc.) do the same thing, so this is likely just a slight flaw that ended up as part of the language.
You'll get an error if you use the wrong one anyway.
Oracle - how to remove white spaces?
It looks like you are executing the query in sqlplus. Sqlplus needs to ensure that there is enough room in the column spacing so the maximum string size can be displayed(255). Usually, the solution is to use the column formatting options(Run prior to the query: column A format A20) to reduce the maximum string size (lines that exceed this length will be displayed over multiple lines).
_DEBUG vs NDEBUG
The macro NDEBUG controls whether assert() statements are active or not.
In my view, that is separate from any other debugging - so I use something other than NDEBUG to control debugging information in the program. What I use varies, depending on the framework I'm working with; different systems have different enabling macros, and I use whatever is appropriate.
If there is no framework, I'd use a name without a leading underscore; those tend to be reserved to 'the implementation' and I try to avoid problems with name collisions - doubly so when the name is a macro.
Cutting the videos based on start and end time using ffmpeg
feel free to use this tool https://github.com/rooty0/ffmpeg_video_cutter I wrote awhile ago
Pretty much that's cli front-end for ffmpeg... you just need to create a yaml what you want to cut out... something like this
cut_method: delete # we're going to delete following video fragments from a video
timeframe:
- from: start # waiting for people to join the conference
to: 4m
- from: 10m11s # awkward silence
to: 15m50s
- from: 30m5s # Off-Topic Discussion
to: end
and then just run a tool to get result
File path to resource in our war/WEB-INF folder?
There's a couple ways of doing this. As long as the WAR file is expanded (a set of files instead of one .war file), you can use this API:
ServletContext context = getContext();
String fullPath = context.getRealPath("/WEB-INF/test/foo.txt");
http://tomcat.apache.org/tomcat-5.5-doc/servletapi/javax/servlet/ServletContext.html#getRealPath(java.lang.String)
That will get you the full system path to the resource you are looking for. However, that won't work if the Servlet Container never expands the WAR file (like Tomcat). What will work is using the ServletContext's getResource methods.
ServletContext context = getContext();
URL resourceUrl = context.getResource("/WEB-INF/test/foo.txt");
or alternatively if you just want the input stream:
InputStream resourceContent = context.getResourceAsStream("/WEB-INF/test/foo.txt");
http://tomcat.apache.org/tomcat-5.5-doc/servletapi/javax/servlet/ServletContext.html#getResource(java.lang.String)
The latter approach will work no matter what Servlet Container you use and where the application is installed. The former approach will only work if the WAR file is unzipped before deployment.
EDIT:
The getContext() method is obviously something you would have to implement. JSP pages make it available as the context field. In a servlet you get it from your ServletConfig which is passed into the servlet's init() method. If you store it at that time, you can get your ServletContext any time you want after that.
Check if a row exists using old mysql_* API
Use mysql_num_rows(), to check if rows are available or not
$result = mysql_query("SELECT * FROM preditors_assigned WHERE lecture_name='$lectureName' LIMIT 1");
$num_rows = mysql_num_rows($result);
if ($num_rows > 0) {
// do something
}
else {
// do something else
}
Shift elements in a numpy array
One way to do it without spilt the code into cases
with array:
def shift(arr, dx, default_value):
result = np.empty_like(arr)
get_neg_or_none = lambda s: s if s < 0 else None
get_pos_or_none = lambda s: s if s > 0 else None
result[get_neg_or_none(dx): get_pos_or_none(dx)] = default_value
result[get_pos_or_none(dx): get_neg_or_none(dx)] = arr[get_pos_or_none(-dx): get_neg_or_none(-dx)]
return result
with matrix it can be done like this:
def shift(image, dx, dy, default_value):
res = np.full_like(image, default_value)
get_neg_or_none = lambda s: s if s < 0 else None
get_pos_or_none = lambda s : s if s > 0 else None
res[get_pos_or_none(-dy): get_neg_or_none(-dy), get_pos_or_none(-dx): get_neg_or_none(-dx)] = \
image[get_pos_or_none(dy): get_neg_or_none(dy), get_pos_or_none(dx): get_neg_or_none(dx)]
return res
Why does writeObject throw java.io.NotSerializableException and how do I fix it?
The fields of your object have in turn their fields, some of which do not implement Serializable. In your case the offending class is TransformGroup. How to solve it?
- if the class is yours, make it
Serializable
- if the class is 3rd party, but you don't need it in the serialized form, mark the field as
transient
- if you need its data and it's third party, consider other means of serialization, like JSON, XML, BSON, MessagePack, etc. where you can get 3rd party objects serialized without modifying their definitions.
HTML5 Audio stop function
first you have to set an id for your audio element
in your js :
var ply = document.getElementById('player');
var oldSrc = ply.src;// just to remember the old source
ply.src = "";// to stop the player you have to replace the source with nothing
Counting the number of non-NaN elements in a numpy ndarray in Python
Quick-to-write alterantive
Even though is not the fastest choice, if performance is not an issue you can use:
sum(~np.isnan(data)).
Performance:
In [7]: %timeit data.size - np.count_nonzero(np.isnan(data))
10 loops, best of 3: 67.5 ms per loop
In [8]: %timeit sum(~np.isnan(data))
10 loops, best of 3: 154 ms per loop
In [9]: %timeit np.sum(~np.isnan(data))
10 loops, best of 3: 140 ms per loop
Inline functions in C#?
In case your assemblies will be ngen-ed, you might want to take a look at TargetedPatchingOptOut. This will help ngen decide whether to inline methods. MSDN reference
It is still only a declarative hint to optimize though, not an imperative command.
Sort matrix according to first column in R
Read the data:
foo <- read.table(text="1 349
1 393
1 392
4 459
3 49
3 32
2 94")
And sort:
foo[order(foo$V1),]
This relies on the fact that order keeps ties in their original order. See ?order.
How to Use Sockets in JavaScript\HTML?
I think it is important to mention, now that this question is over 1 year old, that Socket.IO has since come out and seems to be the primary way to work with sockets in the browser now; it is also compatible with Node.js as far as I know.
What is the difference between response.sendRedirect() and request.getRequestDispatcher().forward(request,response)
Simply difference between Forward(ServletRequest request, ServletResponse response) and sendRedirect(String url) is
forward():
- The
forward() method is executed in the server side.
- The request is transfer to other resource within same server.
- It does not depend on the client’s request protocol since the
forward () method is provided by the servlet container.
- The request is shared by the target resource.
- Only one call is consumed in this method.
- It can be used within server.
- We cannot see forwarded message, it is transparent.
- The forward() method is faster than
sendRedirect() method.
- It is declared in
RequestDispatcher interface.
sendRedirect():
- The
sendRedirect() method is executed in the client side.
- The request is transfer to other resource to different server.
- The
sendRedirect() method is provided under HTTP so it can be used only with HTTP clients.
- New request is created for the destination resource.
- Two request and response calls are consumed.
- It can be used within and outside the server.
- We can see redirected address, it is not transparent.
- The
sendRedirect() method is slower because when new request is created old request object is lost.
- It is declared in
HttpServletResponse.
How to have a drop down <select> field in a rails form?
Please have a look here
Either you can use rails tag Or use plain HTML tags
Rails tag
<%= select("Contact", "email_provider", Contact::PROVIDERS, {:include_blank => true}) %>
*above line of code would become HTML code(HTML Tag), find it below *
HTML tag
<select name="Contact[email_provider]">
<option></option>
<option>yahoo</option>
<option>gmail</option>
<option>msn</option>
</select>
Windows batch script to move files
move c:\Sourcefoldernam\*.* e:\destinationFolder
^ This did not work for me for some reason
But when I tried using quotation marks, it suddenly worked:
move "c:\Sourcefoldernam\*.*" "e:\destinationFolder"
I think its because my directory had spaces in one of the folders. So if it doesn't work for you, try with quotation marks!
Adding Permissions in AndroidManifest.xml in Android Studio?
Go to Android Manifest.xml
and be sure to add the <uses-permission tag > inside the manifest tag but Outside of all other tags..
<manifest xlmns:android...>
<uses-permission android:name="android.permission.INTERNET"></uses-permission>
</manifest>
This is an example of the permission of using Internet.
How to set DateTime to null
It looks like you just want:
eventCustom.DateTimeEnd = string.IsNullOrWhiteSpace(dateTimeEnd)
? (DateTime?) null
: DateTime.Parse(dateTimeEnd);
Note that this will throw an exception if dateTimeEnd isn't a valid date.
An alternative would be:
DateTime validValue;
eventCustom.DateTimeEnd = DateTime.TryParse(dateTimeEnd, out validValue)
? validValue
: (DateTime?) null;
That will now set the result to null if dateTimeEnd isn't valid. Note that TryParse handles null as an input with no problems.
Getting RSA private key from PEM BASE64 Encoded private key file
The problem you'll face is that there's two types of PEM formatted keys: PKCS8 and SSLeay. It doesn't help that OpenSSL seems to use both depending on the command:
The usual openssl genrsa command will generate a SSLeay format PEM. An export from an PKCS12 file with openssl pkcs12 -in file.p12 will create a PKCS8 file.
The latter PKCS8 format can be opened natively in Java using PKCS8EncodedKeySpec. SSLeay formatted keys, on the other hand, can not be opened natively.
To open SSLeay private keys, you can either use BouncyCastle provider as many have done before or Not-Yet-Commons-SSL have borrowed a minimal amount of necessary code from BouncyCastle to support parsing PKCS8 and SSLeay keys in PEM and DER format: http://juliusdavies.ca/commons-ssl/pkcs8.html. (I'm not sure if Not-Yet-Commons-SSL will be FIPS compliant)
Key Format Identification
By inference from the OpenSSL man pages, key headers for two formats are as follows:
PKCS8 Format
Non-encrypted: -----BEGIN PRIVATE KEY-----
Encrypted: -----BEGIN ENCRYPTED PRIVATE KEY-----
SSLeay Format
-----BEGIN RSA PRIVATE KEY-----
(These seem to be in contradiction to other answers but I've tested OpenSSL's output using PKCS8EncodedKeySpec. Only PKCS8 keys, showing ----BEGIN PRIVATE KEY----- work natively)
How to set up devices for VS Code for a Flutter emulator
You do not need to create a virtual device using android studio. You can use your android device running on android 8.0 or higher. All you have to do is to activate developer settings, then enable USB DEBUGGING in the developer settings. Your device will show at the bottom right side of the VS Code. Without enabling the USB debugging, the device may not show.enter image description here
Python: instance has no attribute
Your class doesn't have a __init__(), so by the time it's instantiated, the attribute atoms is not present. You'd have to do C.setdata('something') so C.atoms becomes available.
>>> C = Residues()
>>> C.atoms.append('thing')
Traceback (most recent call last):
File "<pyshell#84>", line 1, in <module>
B.atoms.append('thing')
AttributeError: Residues instance has no attribute 'atoms'
>>> C.setdata('something')
>>> C.atoms.append('thing') # now it works
>>>
Unlike in languages like Java, where you know at compile time what attributes/member variables an object will have, in Python you can dynamically add attributes at runtime. This also implies instances of the same class can have different attributes.
To ensure you'll always have (unless you mess with it down the line, then it's your own fault) an atoms list you could add a constructor:
def __init__(self):
self.atoms = []
How to get rid of blank pages in PDF exported from SSRS
In BIDS or SSDT-BI, do the following:
- Click on Report > Report Properties > Layout tab (Page Setup tab in SSDT-BI)
- Make a note of the values for Page width, Left margin, Right margin
- Close and go back to the design surface
- In the Properties window, select Body
- Click the + symbol to expand the Size node
- Make a note of the value for Width
To render in PDF correctly Body Width + Left margin + Right margin must be less than or equal to Page width. When you see blank pages being rendered it is almost always because the body width plus margins is greater than the page width.
Remember: (Body Width + Left margin + Right margin) <= (Page width)
docker: "build" requires 1 argument. See 'docker build --help'
You need to add a dot, which means to use the Dockerfile in the local directory.
For example:
docker build -t mytag .
It means you use the Dockerfile in the local directory, and if you use docker 1.5 you can specify a Dockerfile elsewhere. Extract from the help output from docker build:
-f, --file="" Name of the Dockerfile(Default is 'Dockerfile' at context root)
JSON serialization/deserialization in ASP.Net Core
You can use Newtonsoft.Json, it's a dependency of Microsoft.AspNet.Mvc.ModelBinding which is a dependency of Microsoft.AspNet.Mvc. So, you don't need to add a dependency in your project.json.
#using Newtonsoft.Json
....
JsonConvert.DeserializeObject(json);
Note, using a WebAPI controller you don't need to deal with JSON.
UPDATE ASP.Net Core 3.0
Json.NET has been removed from the ASP.NET Core 3.0 shared framework.
You can use the new JSON serializer layers on top of the high-performance Utf8JsonReader and Utf8JsonWriter. It deserializes objects from JSON and serializes objects to JSON. Memory allocations are kept minimal and includes support for reading and writing JSON with Stream asynchronously.
To get started, use the JsonSerializer class in the System.Text.Json.Serialization namespace. See the documentation for information and samples.
To use Json.NET in an ASP.NET Core 3.0 project:
services.AddMvc()
.AddNewtonsoftJson();
Read Json.NET support in Migrate from ASP.NET Core 2.2 to 3.0 Preview 2 for more information.
Likelihood of collision using most significant bits of a UUID in Java
According to the documentation, the static method UUID.randomUUID() generates a type 4 UUID.
This means that six bits are used for some type information and the remaining 122 bits are assigned randomly.
The six non-random bits are distributed with four in the most significant half of the UUID and two in the least significant half. So the most significant half of your UUID contains 60 bits of randomness, which means you on average need to generate 2^30 UUIDs to get a collision (compared to 2^61 for the full UUID).
So I would say that you are rather safe. Note, however that this is absolutely not true for other types of UUIDs, as Carl Seleborg mentions.
Incidentally, you would be slightly better off by using the least significant half of the UUID (or just generating a random long using SecureRandom).
Adding a regression line on a ggplot
The simple solution using geom_abline:
geom_abline(slope = coef(data.lm)[[2]], intercept = coef(data.lm)[[1]])
Where data.lm is an lm object, and coef(data.lm) looks something like this:
> coef(data.lm)
(Intercept) DepDelay
-2.006045 1.025109
The numeric indexing assumes that (Intercept) is listed first, which is the case if the model includes an intercept. If you have some other linear model object, just plug in the slope and intercept values similarly.
How to get 30 days prior to current date?
This is an ES6 version
let date = new Date()
let newDate = new Date(date.setDate(date.getDate()-30))
console.log(newDate.getMonth()+1 + '/' + newDate.getDate() + '/' + newDate.getFullYear() )
Why are unnamed namespaces used and what are their benefits?
An anonymous namespace makes the enclosed variables, functions, classes, etc. available only inside that file. In your example it's a way to avoid global variables. There is no runtime or compile time performance difference.
There isn't so much an advantage or disadvantage aside from "do I want this variable, function, class, etc. to be public or private?"
How do I append one string to another in Python?
str1 = "Hello"
str2 = "World"
newstr = " ".join((str1, str2))
That joins str1 and str2 with a space as separators. You can also do "".join(str1, str2, ...). str.join() takes an iterable, so you'd have to put the strings in a list or a tuple.
That's about as efficient as it gets for a builtin method.
PHP DateTime __construct() Failed to parse time string (xxxxxxxx) at position x
This worked for me.
/**
* return date in specific format, given a timestamp.
*
* @param timestamp $datetime
* @return string
*/
public static function showDateString($timestamp)
{
if ($timestamp !== NULL) {
$date = new DateTime();
$date->setTimestamp(intval($timestamp));
return $date->format("d-m-Y");
}
return '';
}
How to resolve TypeError: Cannot convert undefined or null to object
Replace
if (typeof obj === 'undefined') { return undefined;} // return undefined for undefined
if (obj === 'null') { return null;} // null unchanged
with
if (obj === undefined) { return undefined;} // return undefined for undefined
if (obj === null) { return null;} // null unchanged
Conversion failed when converting the varchar value 'simple, ' to data type int
Given that you're only converting to ints to then perform a comparison, I'd just switch the table definition around to using varchar also:
Create table #myTempTable
(
num varchar(12)
)
insert into #myTempTable (num) values (1),(2),(3),(4),(5)
and remove all of the attempted CONVERTs from the rest of the query.
SELECT a.name, a.value AS value, COUNT(*) AS pocet
FROM
(SELECT item.name, value.value
FROM mdl_feedback AS feedback
INNER JOIN mdl_feedback_item AS item
ON feedback.id = item.feedback
INNER JOIN mdl_feedback_value AS value
ON item.id = value.item
WHERE item.typ = 'multichoicerated' AND item.feedback IN (43)
) AS a
INNER JOIN #myTempTable
on a.value = #myTempTable.num
GROUP BY a.name, a.value ORDER BY a.name
How to completely remove Python from a Windows machine?
I know it is an old question, but I ran into this problem with 2.7 and 3.5. Though 2.7 would not show up in my default windows uninstall list, it showed up fine in the ccleaner tools tab under uninstall. Uninstalled and reinstalled afterwards and it has been smooth coding ever since.
How to expand 'select' option width after the user wants to select an option
Okay, this option is pretty hackish but should work.
$(document).ready( function() {
$('#select').change( function() {
$('#hiddenDiv').html( $('#select').val() );
$('#select').width( $('#hiddenDiv').width() );
}
}
Which would offcourse require a hidden div.
<div id="hiddenDiv" style="visibility:hidden"></div>
ohh and you will need jQuery
How to find numbers from a string?
Regular expressions are built to parse. While the syntax can take a while to pick up on this approach is very efficient, and is very flexible for handling more complex string extractions/replacements
Sub Tester()
MsgBox CleanString("3d1fgd4g1dg5d9gdg")
End Sub
Function CleanString(strIn As String) As String
Dim objRegex
Set objRegex = CreateObject("vbscript.regexp")
With objRegex
.Global = True
.Pattern = "[^\d]+"
CleanString = .Replace(strIn, vbNullString)
End With
End Function
What is the usefulness of PUT and DELETE HTTP request methods?
DELETE is for deleting the request resource:
The DELETE method requests that the origin server delete the resource identified by the Request-URI. This method MAY be overridden by human intervention (or other means) on the origin server. The client cannot be guaranteed that the operation has been carried out, even if the status code returned from the origin server indicates that the action has been completed successfully …
PUT is for putting or updating a resource on the server:
The PUT method requests that the enclosed entity be stored under the supplied Request-URI. If the Request-URI refers to an already existing resource, the enclosed entity SHOULD be considered as a modified version of the one residing on the origin server. If the Request-URI does not point to an existing resource, and that URI is capable of being defined as a new resource by the requesting user agent, the origin server can create the resource with that URI …
For the full specification visit:
Since current browsers unfortunately do not support any other verbs than POST and GET in HTML forms, you usually cannot utilize HTTP to it's full extent with them (you can still hijack their submission via JavaScript though). The absence of support for these methods in HTML forms led to URIs containing verbs, like for instance
POST http://example.com/order/1/delete
or even worse
POST http://example.com/deleteOrder/id/1
effectively tunneling CRUD semantics over HTTP. But verbs were never meant to be part of the URI. Instead HTTP already provides the mechanism and semantics to CRUD a Resource (e.g. an order) through the HTTP methods. HTTP is a protocol and not just some data tunneling service.
So to delete a Resource on the webserver, you'd call
DELETE http://example.com/order/1
and to update it you'd call
PUT http://example.com/order/1
and provide the updated Resource Representation in the PUT body for the webserver to apply then.
So, if you are building some sort of client for a REST API, you will likely make it send PUT and DELETE requests. This could be a client built inside a browser, e.g. sending requests via JavaScript or it could be some tool running on a server, etc.
For some more details visit:
PDF Parsing Using Python - extracting formatted and plain texts
You can also take a look at PDFMiner (or for older versions of Python see PDFMiner and PDFMiner).
A particular feature of interest in PDFMiner is that you can control how it regroups text parts when extracting them. You do this by specifying the space between lines, words, characters, etc. So, maybe by tweaking this you can achieve what you want (that depends of the variability of your documents). PDFMiner can also give you the location of the text in the page, it can extract data by Object ID and other stuff. So dig in PDFMiner and be creative!
But your problem is really not an easy one to solve because, in a PDF, the text is not continuous, but made from a lot of small groups of characters positioned absolutely in the page. The focus of PDF is to keep the layout intact. It's not content oriented but presentation oriented.
string.IsNullOrEmpty(string) vs. string.IsNullOrWhiteSpace(string)
The best practice is selecting the most appropriate one.
.Net Framework 4.0 Beta 2 has a new IsNullOrWhiteSpace() method for
strings which generalizes the IsNullOrEmpty() method to also include other white
space besides empty string.
The term “white space” includes all characters that are not visible on
screen. For example, space, line break, tab and empty string are white
space characters*.
Reference : Here
For performance, IsNullOrWhiteSpace is not ideal but is
good. The method calls will result in a small performance penalty.
Further, the IsWhiteSpace method itself has some indirections that can
be removed if you are not using Unicode data. As always, premature
optimization may be evil, but it is also fun.
Reference : Here
Check the source code (Reference Source .NET Framework 4.6.2)
IsNullorEmpty
[Pure]
public static bool IsNullOrEmpty(String value) {
return (value == null || value.Length == 0);
}
IsNullOrWhiteSpace
[Pure]
public static bool IsNullOrWhiteSpace(String value) {
if (value == null) return true;
for(int i = 0; i < value.Length; i++) {
if(!Char.IsWhiteSpace(value[i])) return false;
}
return true;
}
Examples
string nullString = null;
string emptyString = "";
string whitespaceString = " ";
string nonEmptyString = "abc123";
bool result;
result = String.IsNullOrEmpty(nullString); // true
result = String.IsNullOrEmpty(emptyString); // true
result = String.IsNullOrEmpty(whitespaceString); // false
result = String.IsNullOrEmpty(nonEmptyString); // false
result = String.IsNullOrWhiteSpace(nullString); // true
result = String.IsNullOrWhiteSpace(emptyString); // true
result = String.IsNullOrWhiteSpace(whitespaceString); // true
result = String.IsNullOrWhiteSpace(nonEmptyString); // false
Jdbctemplate query for string: EmptyResultDataAccessException: Incorrect result size: expected 1, actual 0
Since returning a null when there is no data is something I want to do often when using queryForObject I have found it useful to extend JdbcTemplate and add a queryForNullableObject method similar to below.
public class JdbcTemplateExtended extends JdbcTemplate {
public JdbcTemplateExtended(DataSource datasource){
super(datasource);
}
public <T> T queryForNullableObject(String sql, RowMapper<T> rowMapper) throws DataAccessException {
List<T> results = query(sql, rowMapper);
if (results == null || results.isEmpty()) {
return null;
}
else if (results.size() > 1) {
throw new IncorrectResultSizeDataAccessException(1, results.size());
}
else{
return results.iterator().next();
}
}
public <T> T queryForNullableObject(String sql, Class<T> requiredType) throws DataAccessException {
return queryForObject(sql, getSingleColumnRowMapper(requiredType));
}
}
You can now use this in your code the same way you used queryForObject
String result = queryForNullableObject(queryString, String.class);
I would be interested to know if anyone else thinks this is a good idea?
java get file size efficiently
When I modify your code to use a file accessed by an absolute path instead of a resource, I get a different result (for 1 run, 1 iteration, and a 100,000 byte file -- times for a 10 byte file are identical to 100,000 bytes)
LENGTH sum: 33, per Iteration: 33.0
CHANNEL sum: 3626, per Iteration: 3626.0
URL sum: 294, per Iteration: 294.0
How can I output a UTF-8 CSV in PHP that Excel will read properly?
In my case following works very nice to make CSV file with UTF-8 chars displayed correctly in Excel.
$out = fopen('php://output', 'w');
fprintf($out, chr(0xEF).chr(0xBB).chr(0xBF));
fputcsv($out, $some_csv_strings);
The 0xEF 0xBB 0xBF BOM header will let Excel know the correct encoding.
How to use awk sort by column 3
To exclude the first line (header) from sorting, I split it out into two buffers.
df | awk 'BEGIN{header=""; $body=""} { if(NR==1){header=$0}else{body=body"\n"$0}} END{print header; print body|"sort -nk3"}'
Iterating Through a Dictionary in Swift
You can also use values.makeIterator() to iterate over dict values, like this:
for sb in sbItems.values.makeIterator(){
// do something with your sb item..
print(sb)
}
You can also do the iteration like this, in a more swifty style:
sbItems.values.makeIterator().forEach{
// $0 is your dict value..
print($0)
}
sbItems is dict of type [String : NSManagedObject]
Alternative to Intersect in MySQL
Break your problem in 2 statements: firstly, you want to select all if
(id=3 and cut_name= '?????' and cut_name='??')
is true . Secondly, you want to select all if
(id=3) and ( cut_name='?????' or cut_name='??')
is true. So, we will join both by OR because we want to select all if anyone of them is true.
select * from emovis_reporting
where (id=3 and cut_name= '?????' and cut_name='??') OR
( (id=3) and ( cut_name='?????' or cut_name='??') )
Get data from file input in JQuery
FileReader API with jQuery, simple example.
_x000D_
_x000D_
( function ( $ ) {_x000D_
// Add click event handler to button_x000D_
$( '#load-file' ).click( function () {_x000D_
if ( ! window.FileReader ) {_x000D_
return alert( 'FileReader API is not supported by your browser.' );_x000D_
}_x000D_
var $i = $( '#file' ), // Put file input ID here_x000D_
input = $i[0]; // Getting the element from jQuery_x000D_
if ( input.files && input.files[0] ) {_x000D_
file = input.files[0]; // The file_x000D_
fr = new FileReader(); // FileReader instance_x000D_
fr.onload = function () {_x000D_
// Do stuff on onload, use fr.result for contents of file_x000D_
$( '#file-content' ).append( $( '<div/>' ).html( fr.result ) )_x000D_
};_x000D_
//fr.readAsText( file );_x000D_
fr.readAsDataURL( file );_x000D_
} else {_x000D_
// Handle errors here_x000D_
alert( "File not selected or browser incompatible." )_x000D_
}_x000D_
} );_x000D_
} )( jQuery );
_x000D_
<script src="https://ajax.googleapis.com/ajax/libs/jquery/2.1.1/jquery.min.js"></script>_x000D_
<input type="file" id="file" />_x000D_
<input type='button' id='load-file' value='Load'>_x000D_
<div id="file-content"></div>
_x000D_
_x000D_
_x000D_
To read as text... uncomment //fr.readAsText(file); line and comment fr.readAsDataURL(file);
HTML: Changing colors of specific words in a string of text
Tailor this code however you like to fit your needs, you can select text? in the paragraph to be what font or style you need!:
<head>
<style>
p{ color:#ff0000;font-family: "Times New Roman", Times, serif;}
font{color:#000fff;background:#000000;font-size:225%;}
b{color:green;}
</style>
</head>
<body>
<p>This is your <b>text. <font>Type</font></strong></b>what you like</p>
</body>
Docker-Compose persistent data MySQL
There are 3 ways:
First way
You need specify the directory to store mysql data on your host machine. You can then remove the data container. Your mysql data will be saved on you local filesystem.
Mysql container definition must look like this:
mysql:
container_name: flask_mysql
restart: always
image: mysql:latest
environment:
MYSQL_ROOT_PASSWORD: 'test_pass' # TODO: Change this
MYSQL_USER: 'test'
MYSQL_PASS: 'pass'
volumes:
- /opt/mysql_data:/var/lib/mysql
ports:
- "3306:3306"
Second way
Would be to commit the data container before typing docker-compose down:
docker commit my_data_container
docker-compose down
Third way
Also you can use docker-compose stop instead of docker-compose down (then you don't need to commit the container)
Eloquent get only one column as an array
I came across this question and thought I would clarify that the lists() method of a eloquent builder object was depreciated in Laravel 5.2 and replaced with pluck().
// <= Laravel 5.1
Word_relation::where('word_one', $word_id)->lists('word_one')->toArray();
// >= Laravel 5.2
Word_relation::where('word_one', $word_id)->pluck('word_one')->toArray();
These methods can also be called on a Collection for example
// <= Laravel 5.1
$collection = Word_relation::where('word_one', $word_id)->get();
$array = $collection->lists('word_one');
// >= Laravel 5.2
$collection = Word_relation::where('word_one', $word_id)->get();
$array = $collection->pluck('word_one');
How to create an array containing 1...N
Using new Array methods and => function syntax from ES6 standard (only Firefox at the time of writing).
By filling holes with undefined:
Array(N).fill().map((_, i) => i + 1);
Array.from turns "holes" into undefined so Array.map works as expected:
Array.from(Array(5)).map((_, i) => i + 1)
Disable Laravel's Eloquent timestamps
You can temporarily disable timestamps
$timestamps = $user->timestamps;
$user->timestamps=false; // avoid view updating the timestamp
$user->last_logged_in_at = now();
$user->save();
$user->timestamps=$timestamps; // restore timestamps
How to set OnClickListener on a RadioButton in Android?
The question was about Detecting which radio button is clicked, this is how you can get which button is clicked
final RadioGroup radio = (RadioGroup) dialog.findViewById(R.id.radioGroup1);
radio.setOnCheckedChangeListener(new OnCheckedChangeListener() {
@Override
public void onCheckedChanged(RadioGroup group, int checkedId) {
View radioButton = radio.findViewById(checkedId);
int index = radio.indexOfChild(radioButton);
// Add logic here
switch (index) {
case 0: // first button
Toast.makeText(getApplicationContext(), "Selected button number " + index, 500).show();
break;
case 1: // secondbutton
Toast.makeText(getApplicationContext(), "Selected button number " + index, 500).show();
break;
}
}
});
Deleting objects from an ArrayList in Java
You could iterate backwards and remove as you go through the ArrayList. This has the advantage of subsequent elements not needing to shift and is easier to program than moving forwards.
Excel 2013 horizontal secondary axis
You should follow the guidelines on Add a secondary horizontal axis:
Add a secondary horizontal axis
To complete this procedure, you must have a chart that displays a secondary vertical axis. To add a secondary vertical axis, see Add a secondary vertical axis.
Click a chart that displays a secondary vertical axis.
This displays the Chart Tools, adding the Design, Layout, and Format tabs.
On the Layout tab, in the Axes group, click Axes.
Click Secondary Horizontal Axis, and then click the display option that you want.
Add a secondary vertical axis
You can plot data on a secondary vertical axis one data series at a time. To plot more than one data series on the secondary vertical axis, repeat this procedure for each data series that you want to display on the secondary vertical axis.
In a chart, click the data series that you want to plot on a secondary vertical axis, or do the following to select the data series from a list of chart elements:
Click the chart.
This displays the Chart Tools, adding the Design, Layout, and Format tabs.
On the Format tab, in the Current Selection group, click the arrow in the Chart Elements box, and then click the data series that you want to plot along a secondary vertical axis.
On the Format tab, in the Current Selection group, click Format Selection.
The Format Data Series dialog box is displayed.
Note: If a different dialog box is displayed, repeat step 1 and make sure that you select a data series in the chart.
On the Series Options tab, under Plot Series On, click Secondary Axis and then click Close.
A secondary vertical axis is displayed in the chart.
To change the display of the secondary vertical axis, do the following:
On the Layout tab, in the Axes group, click Axes.
Click Secondary Vertical Axis, and then click the display option that you want.
To change the axis options of the secondary vertical axis, do the following:
Right-click the secondary vertical axis, and then click Format Axis.
Under Axis Options, select the options that you want to use.
How to print a groupby object
Another simple alternative:
for name_of_the_group, group in grouped_dataframe:
print (name_of_the_group)
print (group)
How to add an extra column to a NumPy array
np.r_[ ... ] and np.c_[ ... ]
are useful alternatives to vstack and hstack,
with square brackets [] instead of round ().
A couple of examples:
: import numpy as np
: N = 3
: A = np.eye(N)
: np.c_[ A, np.ones(N) ] # add a column
array([[ 1., 0., 0., 1.],
[ 0., 1., 0., 1.],
[ 0., 0., 1., 1.]])
: np.c_[ np.ones(N), A, np.ones(N) ] # or two
array([[ 1., 1., 0., 0., 1.],
[ 1., 0., 1., 0., 1.],
[ 1., 0., 0., 1., 1.]])
: np.r_[ A, [A[1]] ] # add a row
array([[ 1., 0., 0.],
[ 0., 1., 0.],
[ 0., 0., 1.],
[ 0., 1., 0.]])
: # not np.r_[ A, A[1] ]
: np.r_[ A[0], 1, 2, 3, A[1] ] # mix vecs and scalars
array([ 1., 0., 0., 1., 2., 3., 0., 1., 0.])
: np.r_[ A[0], [1, 2, 3], A[1] ] # lists
array([ 1., 0., 0., 1., 2., 3., 0., 1., 0.])
: np.r_[ A[0], (1, 2, 3), A[1] ] # tuples
array([ 1., 0., 0., 1., 2., 3., 0., 1., 0.])
: np.r_[ A[0], 1:4, A[1] ] # same, 1:4 == arange(1,4) == 1,2,3
array([ 1., 0., 0., 1., 2., 3., 0., 1., 0.])
(The reason for square brackets [] instead of round ()
is that Python expands e.g. 1:4 in square --
the wonders of overloading.)
How to get unique values in an array
Another thought of this question. Here is what I did to achieve this with fewer code.
_x000D_
_x000D_
var distinctMap = {};_x000D_
var testArray = ['John', 'John', 'Jason', 'Jason'];_x000D_
for (var i = 0; i < testArray.length; i++) {_x000D_
var value = testArray[i];_x000D_
distinctMap[value] = '';_x000D_
};_x000D_
var unique_values = Object.keys(distinctMap);_x000D_
_x000D_
console.log(unique_values);
_x000D_
_x000D_
_x000D_
file_get_contents behind a proxy?
To use file_get_contents() over/through a proxy that doesn't require authentication, something like this should do :
(I'm not able to test this one : my proxy requires an authentication)
$aContext = array(
'http' => array(
'proxy' => 'tcp://192.168.0.2:3128',
'request_fulluri' => true,
),
);
$cxContext = stream_context_create($aContext);
$sFile = file_get_contents("http://www.google.com", False, $cxContext);
echo $sFile;
Of course, replacing the IP and port of my proxy by those which are OK for yours ;-)
If you're getting that kind of error :
Warning: file_get_contents(http://www.google.com) [function.file-get-contents]: failed to open stream: HTTP request failed! HTTP/1.0 407 Proxy Authentication Required
It means your proxy requires an authentication.
If the proxy requires an authentication, you'll have to add a couple of lines, like this :
$auth = base64_encode('LOGIN:PASSWORD');
$aContext = array(
'http' => array(
'proxy' => 'tcp://192.168.0.2:3128',
'request_fulluri' => true,
'header' => "Proxy-Authorization: Basic $auth",
),
);
$cxContext = stream_context_create($aContext);
$sFile = file_get_contents("http://www.google.com", False, $cxContext);
echo $sFile;
Same thing about IP and port, and, this time, also LOGIN and PASSWORD ;-) Check out all valid http options.
Now, you are passing an Proxy-Authorization header to the proxy, containing your login and password.
And... The page should be displayed ;-)
Matplotlib color according to class labels
The accepted answer has it spot on, but if you might want to specify which class label should be assigned to a specific color or label you could do the following. I did a little label gymnastics with the colorbar, but making the plot itself reduces to a nice one-liner. This works great for plotting the results from classifications done with sklearn. Each label matches a (x,y) coordinate.
import matplotlib
import matplotlib.pyplot as plt
import numpy as np
x = [4,8,12,16,1,4,9,16]
y = [1,4,9,16,4,8,12,3]
label = [0,1,2,3,0,1,2,3]
colors = ['red','green','blue','purple']
fig = plt.figure(figsize=(8,8))
plt.scatter(x, y, c=label, cmap=matplotlib.colors.ListedColormap(colors))
cb = plt.colorbar()
loc = np.arange(0,max(label),max(label)/float(len(colors)))
cb.set_ticks(loc)
cb.set_ticklabels(colors)
Using a slightly modified version of this answer, one can generalise the above for N colors as follows:
import numpy as np
import matplotlib as mpl
import matplotlib.pyplot as plt
N = 23 # Number of labels
# setup the plot
fig, ax = plt.subplots(1,1, figsize=(6,6))
# define the data
x = np.random.rand(1000)
y = np.random.rand(1000)
tag = np.random.randint(0,N,1000) # Tag each point with a corresponding label
# define the colormap
cmap = plt.cm.jet
# extract all colors from the .jet map
cmaplist = [cmap(i) for i in range(cmap.N)]
# create the new map
cmap = cmap.from_list('Custom cmap', cmaplist, cmap.N)
# define the bins and normalize
bounds = np.linspace(0,N,N+1)
norm = mpl.colors.BoundaryNorm(bounds, cmap.N)
# make the scatter
scat = ax.scatter(x,y,c=tag,s=np.random.randint(100,500,N),cmap=cmap, norm=norm)
# create the colorbar
cb = plt.colorbar(scat, spacing='proportional',ticks=bounds)
cb.set_label('Custom cbar')
ax.set_title('Discrete color mappings')
plt.show()
Which gives:
How to get multiple selected values of select box in php?
I fix my problem with javascript + HTML. First i check selected options and save its in a hidden field of my form:
for(i=0; i < form.select.options.length; i++)
if (form.select.options[i].selected)
form.hidden.value += form.select.options[i].value;
Next, i get by post that field and get all the string ;-)
I hope it'll be work for somebody more. Thanks to all.
list all files in the folder and also sub folders
Using you current code, make this tweak:
public void listf(String directoryName, List<File> files) {
File directory = new File(directoryName);
// Get all files from a directory.
File[] fList = directory.listFiles();
if(fList != null)
for (File file : fList) {
if (file.isFile()) {
files.add(file);
} else if (file.isDirectory()) {
listf(file.getAbsolutePath(), files);
}
}
}
}
Find duplicate records in MySQL
Fastest duplicates removal queries procedure:
/* create temp table with one primary column id */
INSERT INTO temp(id) SELECT MIN(id) FROM list GROUP BY (isbn) HAVING COUNT(*)>1;
DELETE FROM list WHERE id IN (SELECT id FROM temp);
DELETE FROM temp;
PHP regular expression - filter number only
This is the right answer
preg_match("/^[0-9]+$/", $yourstr);
This function return TRUE(1) if it matches or FALSE(0) if it doesn't
Quick Explanation :
'^' : means that it should begin with the following ( in our case is a range of digital numbers [0-9] )
( to avoid cases like ("abdjdf125") )
'+' : means there should be at least one digit
'$' : means after our pattern the string should end
( to avoid cases like ("125abdjdf") )
How should I store GUID in MySQL tables?
if you have a char/varchar value formatted as the standard GUID, you can simply store it as BINARY(16) using the simple CAST(MyString AS BINARY16), without all those mind-boggling sequences of CONCAT + SUBSTR.
BINARY(16) fields are compared/sorted/indexed much faster than strings, and also take two times less space in the database
Select a Column in SQL not in Group By
The direct answer is that you can't. You must select either an aggregate or something that you are grouping by.
So, you need an alternative approach.
1). Take you current query and join the base data back on it
SELECT
cpe.*
FROM
Filteredfmgcms_claimpaymentestimate cpe
INNER JOIN
(yourQuery) AS lookup
ON lookup.MaxData = cpe.createdOn
AND lookup.fmgcms_cpeclaimid = cpe.fmgcms_cpeclaimid
2). Use a CTE to do it all in one go...
WITH
sequenced_data AS
(
SELECT
*,
ROW_NUMBER() OVER (PARITION BY fmgcms_cpeclaimid ORDER BY CreatedOn DESC) AS sequence_id
FROM
Filteredfmgcms_claimpaymentestimate
WHERE
createdon < 'reportstartdate'
)
SELECT
*
FROM
sequenced_data
WHERE
sequence_id = 1
NOTE: Using ROW_NUMBER() will ensure just one record per fmgcms_cpeclaimid. Even if multiple records are tied with the exact same createdon value. If you can have ties, and want all records with the same createdon value, use RANK() instead.
What does from __future__ import absolute_import actually do?
The changelog is sloppily worded. from __future__ import absolute_import does not care about whether something is part of the standard library, and import string will not always give you the standard-library module with absolute imports on.
from __future__ import absolute_import means that if you import string, Python will always look for a top-level string module, rather than current_package.string. However, it does not affect the logic Python uses to decide what file is the string module. When you do
python pkg/script.py
pkg/script.py doesn't look like part of a package to Python. Following the normal procedures, the pkg directory is added to the path, and all .py files in the pkg directory look like top-level modules. import string finds pkg/string.py not because it's doing a relative import, but because pkg/string.py appears to be the top-level module string. The fact that this isn't the standard-library string module doesn't come up.
To run the file as part of the pkg package, you could do
python -m pkg.script
In this case, the pkg directory will not be added to the path. However, the current directory will be added to the path.
You can also add some boilerplate to pkg/script.py to make Python treat it as part of the pkg package even when run as a file:
if __name__ == '__main__' and __package__ is None:
__package__ = 'pkg'
However, this won't affect sys.path. You'll need some additional handling to remove the pkg directory from the path, and if pkg's parent directory isn't on the path, you'll need to stick that on the path too.
Caused By: java.lang.NoClassDefFoundError: org/apache/log4j/Logger
Check in Deployment Assembly,
I have the same error, when i generate the war file with the "maven clean install" way and deploy manualy, it works fine, but when i use the runtime enviroment (eclipse) the problems come.
The solution for me (for eclipse IDE) go to: "proyect properties" --> "Deployment Assembly" --> "Add" --> "the jar you need", in my case java "build path entries".
Maybe can help a litle!
Post parameter is always null
I know the OP was originally sending a single string, but for future reference, it is also worth noting that malformed JSON will also arrive as null into the post method. In my case, a missing comma between two properties caused what was otherwise fine, to break.
CMD what does /im (taskkill)?
It tells taskkill that the next parameter something.exe is an image name, a.k.a executable name
C:\>taskkill /?
TASKKILL [/S system [/U username [/P [password]]]]
{ [/FI filter] [/PID processid | /IM imagename] } [/T] [/F]
Description:
This tool is used to terminate tasks by process id (PID) or image name.
Parameter List:
/S system Specifies the remote system to connect to.
/U [domain\]user Specifies the user context under which the
command should execute.
/P [password] Specifies the password for the given user
context. Prompts for input if omitted.
/FI filter Applies a filter to select a set of tasks.
Allows "*" to be used. ex. imagename eq acme*
/PID processid Specifies the PID of the process to be terminated.
Use TaskList to get the PID.
/IM imagename Specifies the image name of the process
to be terminated. Wildcard '*' can be used
to specify all tasks or image names.
/T Terminates the specified process and any
child processes which were started by it.
/F Specifies to forcefully terminate the process(es).
/? Displays this help message.
What is the difference between java and core java?
A simple step to understand what is java and core java.
Actual result: both have almost same content.
Result: Java and core java is same.
core java is just slang, to emphasize on deep knowledge of basic java.
but if I say I know Java it doesn't mean that I don't have deep knowledge of basic java, or if I know everything in java.
Word-wrap in an HTML table
Tested in IE 8 and Chrome 13.
<table style="table-layout: fixed; width: 100%">
<tr>
<td>
<div style="word-wrap: break-word;">
longtexthere
</div>
</td>
<td><span style="display: inline;">Foo</span></td>
</tr>
</table>
This causes the table to fit the width of the page and each column to take up 50% of the width.
If you prefer the first column to take up more of the page, add a width: 80% to the td as in the following example, replacing 80% with the percentage of your choice.
<table style="table-layout: fixed; width: 100%">
<tr>
<td style="width:80%">
<div style="word-wrap: break-word;">
longtexthere
</div>
</td>
<td><span style="display: inline;">Foo</span></td>
</tr>
</table>
Get each line from textarea
You could use PHP constant:
$array = explode(PHP_EOL, $text);
additional notes:
1. For me this is the easiest and the safest way because it is cross platform compatible (Windows/Linux etc.)
2. It is better to use PHP CONSTANT whenever you can for faster execution
How to create a scrollable Div Tag Vertically?
This code creates a nice vertical scrollbar for me in Firefox and Chrome:
_x000D_
_x000D_
#answerform {
position: absolute;
border: 5px solid gray;
padding: 5px;
background: white;
width: 300px;
height: 400px;
overflow-y: scroll;
}
_x000D_
<div id='answerform'>
badger<br><br>badger<br><br>badger<br><br>badger<br><br>badger<br><br> mushroom
<br><br>mushroom<br><br> a badger<br><br>badger<br><br>badger<br><br>badger<br><br>badger<br><br>
</div>
_x000D_
_x000D_
_x000D_
Here is a JS fiddle demo proving the above works.
How to create temp table using Create statement in SQL Server?
A temporary table can have 3 kinds, the # is the most used. This is a temp table that only exists in the current session.
An equivalent of this is @, a declared table variable. This has a little less "functions" (like indexes etc) and is also only used for the current session.
The ## is one that is the same as the #, however, the scope is wider, so you can use it within the same session, within other stored procedures.
You can create a temp table in various ways:
declare @table table (id int)
create table #table (id int)
create table ##table (id int)
select * into #table from xyz
Scale an equation to fit exact page width
I just had the situation that I wanted this only for lines exceeding \linewidth, that is: Squeezing long lines slightly.
Since it took me hours to figure this out, I would like to add it here.
I want to emphasize that scaling fonts in LaTeX is a deadly sin!
In nearly every situation, there is a better way (e.g. multline of the mathtools package). So use it conscious.
In this particular case, I had no influence on the code base apart the preamble and some lines slightly overshooting the page border when I compiled it as an eBook-scaled pdf.
\usepackage{environ} % provides \BODY
\usepackage{etoolbox} % provides \ifdimcomp
\usepackage{graphicx} % provides \resizebox
\newlength{\myl}
\let\origequation=\equation
\let\origendequation=\endequation
\RenewEnviron{equation}{
\settowidth{\myl}{$\BODY$} % calculate width and save as \myl
\origequation
\ifdimcomp{\the\linewidth}{>}{\the\myl}
{\ensuremath{\BODY}} % True
{\resizebox{\linewidth}{!}{\ensuremath{\BODY}}} % False
\origendequation
}
Before
After
A component is changing an uncontrolled input of type text to be controlled error in ReactJS
In my case it was pretty much what Mayank Shukla's top answer says. The only detail was that my state was lacking completely the property I was defining.
For example, if you have this state:
state = {
"a" : "A",
"b" : "B",
}
If you're expanding your code, you might want to add a new prop so, someplace else in your code you might create a new property c whose value is not only undefined on the component's state but the property itself is undefined.
To solve this just make sure to add c into your state and give it a proper initial value.
e.g.,
state = {
"a" : "A",
"b" : "B",
"c" : "C", // added and initialized property!
}
Hope I was able to explain my edge case.
How do I call a non-static method from a static method in C#?
Apologized to post answer for very old thread but i believe my answer may help other.
With the help of delegate the same thing can be achieved.
public class MyClass
{
private static Action NonStaticDelegate;
public void NonStaticMethod()
{
Console.WriteLine("Non-Static!");
}
public static void CaptureDelegate()
{
MyClass temp = new MyClass();
MyClass.NonStaticDelegate = new Action(temp.NonStaticMethod);
}
public static void RunNonStaticMethod()
{
if (MyClass.NonStaticDelegate != null)
{
// This will run the non-static method.
// Note that you still needed to create an instance beforehand
MyClass.NonStaticDelegate();
}
}
}
Case-Insensitive List Search
I realise this is an old post, but just in case anyone else is looking, you can use Contains by providing the case insensitive string equality comparer like so:
using System.Linq;
// ...
if (testList.Contains(keyword, StringComparer.OrdinalIgnoreCase))
{
Console.WriteLine("Keyword Exists");
}
This has been available since .net 2.0 according to msdn.
How do I make a simple makefile for gcc on Linux?
Interesting, I didn't know make would default to using the C compiler given rules regarding source files.
Anyway, a simple solution that demonstrates simple Makefile concepts would be:
HEADERS = program.h headers.h
default: program
program.o: program.c $(HEADERS)
gcc -c program.c -o program.o
program: program.o
gcc program.o -o program
clean:
-rm -f program.o
-rm -f program
(bear in mind that make requires tab instead of space indentation, so be sure to fix that when copying)
However, to support more C files, you'd have to make new rules for each of them. Thus, to improve:
HEADERS = program.h headers.h
OBJECTS = program.o
default: program
%.o: %.c $(HEADERS)
gcc -c $< -o $@
program: $(OBJECTS)
gcc $(OBJECTS) -o $@
clean:
-rm -f $(OBJECTS)
-rm -f program
I tried to make this as simple as possible by omitting variables like $(CC) and $(CFLAGS) that are usually seen in makefiles. If you're interested in figuring that out, I hope I've given you a good start on that.
Here's the Makefile I like to use for C source. Feel free to use it:
TARGET = prog
LIBS = -lm
CC = gcc
CFLAGS = -g -Wall
.PHONY: default all clean
default: $(TARGET)
all: default
OBJECTS = $(patsubst %.c, %.o, $(wildcard *.c))
HEADERS = $(wildcard *.h)
%.o: %.c $(HEADERS)
$(CC) $(CFLAGS) -c $< -o $@
.PRECIOUS: $(TARGET) $(OBJECTS)
$(TARGET): $(OBJECTS)
$(CC) $(OBJECTS) -Wall $(LIBS) -o $@
clean:
-rm -f *.o
-rm -f $(TARGET)
It uses the wildcard and patsubst features of the make utility to automatically include .c and .h files in the current directory, meaning when you add new code files to your directory, you won't have to update the Makefile. However, if you want to change the name of the generated executable, libraries, or compiler flags, you can just modify the variables.
In either case, don't use autoconf, please. I'm begging you! :)
How should I deal with "package 'xxx' is not available (for R version x.y.z)" warning?
I found a slight variation on #6 package is out of date from the excellent solution by @Richie Cotton.
Sometimes the package maintainer may show R version gaps that it does not support. In that case, you have at least two options: 1) upgrade your R version to the next one the target package already supports, 2) install the most recent version from the older ones available that would work with your R version.
A concrete example: the latest CRAN version of package rattle for data mining, 5.3.0, does not support R version 3.4 because it had a big update between package versions 5.2.0 (R >= 2.13.0) and 5.3.0 (R >=3.5).
In a case like this, the alternative to upgrading the R installation is the solution already mentioned. Install the package devtools if you don't have it (it includes package remotes) and then install the specific version that will work in your current R. You can look up that information on the CRAN page for the specific package archives.
library("devtools")
install_version("rattle", version = "5.2.0", repos = "http://cran.us.r-project.org")
Create a file if one doesn't exist - C
You typically have to do this in a single syscall, or else you will get a race condition.
This will open for reading and writing, creating the file if necessary.
FILE *fp = fopen("scores.dat", "ab+");
If you want to read it and then write a new version from scratch, then do it as two steps.
FILE *fp = fopen("scores.dat", "rb");
if (fp) {
read_scores(fp);
}
// Later...
// truncates the file
FILE *fp = fopen("scores.dat", "wb");
if (!fp)
error();
write_scores(fp);
Regular expression "^[a-zA-Z]" or "[^a-zA-Z]"
Yes, the first means "match all strings that start with a letter", the second means "match all strings that contain a non-letter". The caret ("^") is used in two different ways, one to signal the start of the text, one to negate a character match inside square brackets.
How to place div side by side
Give the first div float: left; and a fixed width, and give the second div width: 100%; and float: left;. That should do the trick. If you want to place items below it you need a clear: both; on the item you want to place below it.
jQuery select change show/hide div event
change your jquery method to
$(function () { /* DOM ready */
$("#type").change(function () {
alert('The option with value ' + $(this).val());
//hide the element you want to hide here with
//("id").attr("display","block"); // to show
//("id").attr("display","none"); // to hide
});
});
How to enable CORS in ASP.net Core WebAPI
For .NET CORE 3.1
In my case, I was using https redirection just before adding cors middleware and able to fix the issue by changing order of them
What i mean is:
change this:
public void Configure(IApplicationBuilder app, IWebHostEnvironment env)
{
...
app.UseHttpsRedirection();
app.UseCors(x => x
.AllowAnyOrigin()
.AllowAnyMethod()
.AllowAnyHeader());
...
}
to this:
public void Configure(IApplicationBuilder app, IWebHostEnvironment env)
{
...
app.UseCors(x => x
.AllowAnyOrigin()
.AllowAnyMethod()
.AllowAnyHeader());
app.UseHttpsRedirection();
...
}
By the way, allowing requests from any origins and methods may not be a good idea for production stage, you should write your own cors policies at production.
Best place to insert the Google Analytics code
As google says:
Paste it into your web page, just before the closing </head> tag.
One of the main advantages of the asynchronous snippet is that you can
position it at the top of the HTML document. This increases the
likelihood that the tracking beacon will be sent before the user
leaves the page. It is customary to place JavaScript code in the
<head> section, and we recommend placing the snippet at the bottom of
the <head> section for best performance
Calling another method java GUI
I'm not sure what you're trying to do, but here's something to consider: c(); won't do anything. c is an instance of the class checkbox and not a method to be called. So consider this:
public class FirstWindow extends JFrame { public FirstWindow() { checkbox c = new checkbox(); c.yourMethod(yourParameters); // call the method you made in checkbox } } public class checkbox extends JFrame { public checkbox(yourParameters) { // this is the constructor method used to initialize instance variables } public void yourMethod() // doesn't have to be void { // put your code here } }
How to add an element to a list?
import json
myDict = {'dict': [{'a': 'none', 'b': 'none', 'c': 'none'}]}
test = json.dumps(myDict)
print(test)
{"dict": [{"a": "none", "b": "none", "c": "none"}]}
myDict['dict'].append(({'a': 'aaaa', 'b': 'aaaa', 'c': 'aaaa'}))
test = json.dumps(myDict)
print(test)
{"dict": [{"a": "none", "b": "none", "c": "none"}, {"a": "aaaa", "b": "aaaa", "c": "aaaa"}]}
Define global variable with webpack
I solved this issue by setting the global variables as a static properties on the classes to which they are most relevant. In ES5 it looks like this:
var Foo = function(){...};
Foo.globalVar = {};
what are the .map files used for in Bootstrap 3.x?
From Working with CSS preprocessors in Chrome DevTools:
Many developers generate CSS style sheets using a CSS preprocessor, such as Sass, Less, or Stylus. Because the CSS files are generated, editing the CSS files directly is not as helpful.
For preprocessors that support CSS source maps, DevTools lets you live-edit your preprocessor source files in the Sources panel, and view the results without having to leave DevTools or refresh the page. When you inspect an element whose styles are provided by a generated CSS file, the Elements panel displays a link to the original source file, not the generated .css file.
CAST DECIMAL to INT
1 cent:
no space b/w CAST and (expression).
i.e., CAST(columnName AS SIGNED).
How to force a UIViewController to Portrait orientation in iOS 6
If you want all of our navigation controllers to respect the top view controller you can use a category so you don't have to go through and change a bunch of class names.
@implementation UINavigationController (Rotation_IOS6)
-(BOOL)shouldAutorotate
{
return [[self.viewControllers lastObject] shouldAutorotate];
}
-(NSUInteger)supportedInterfaceOrientations
{
return [[self.viewControllers lastObject] supportedInterfaceOrientations];
}
- (UIInterfaceOrientation)preferredInterfaceOrientationForPresentation
{
return [[self.viewControllers lastObject] preferredInterfaceOrientationForPresentation];
}
@end
As a few of the comments point to, this is a quick fix to the problem. A better solution is subclass UINavigationController and put these methods there. A subclass also helps for supporting 6 and 7.
How can I use console logging in Internet Explorer?
For IE8 or console support limited to console.log (no debug, trace, ...) you can do the following:
If console OR console.log undefined: Create dummy functions for
console functions (trace, debug, log, ...)
window.console = {
debug : function() {}, ...};
Else if console.log is defined (IE8) AND console.debug (any other) is not defined: redirect all logging functions to console.log, this allows to keep those logs !
window.console = {
debug : window.console.log, ...};
Not sure about the assert support in various IE versions, but any suggestions are welcome.
