Programs & Examples On #Compare contrast

How to start jenkins on different port rather than 8080 using command prompt in Windows?

Correct, use --httpPort parameter. If you also want to specify the $JENKINS_HOME, you can do like this:

java -DJENKINS_HOME=/Users/Heros/jenkins -jar jenkins.war  --httpPort=8484

How to run PyCharm in Ubuntu - "Run in Terminal" or "Run"?

For Pycharm CE 2018.3 and Ubuntu 18.04 with snap installation:

env BAMF_DESKTOP_FILE_HINT=/var/lib/snapd/desktop/applications/pycharm-community_pycharm-community.desktop /snap/bin/pycharm-community %f

I get this command from KDE desktop launch icon.

pychar-ce-command

Sorry for the language but I am a Spanish developer so I have my system in Spanish.

Replace new lines with a comma delimiter with Notepad++?

USE Chrome's Search Bar

1-press CTRL F
2-paste the copied text in search bar
3-press CTRL A followed by CTRL C to copy the text again from search
4-paste in Notepad++
5-replace 'space' with ','

1-click for image
2-click for image

Failed to execute goal org.apache.maven.plugins:maven-surefire-plugin:2.12:test (default-test) on project.

Change the version number to 2.19.1 works for me :)

`<plugin>
    <groupId>org.apache.maven.plugins</groupId>
    <artifactId>maven-surefire-plugin</artifactId>
    <version>2.19.1</version>
    <configuration>
        <systemPropertyVariables>
            <xmlOutputDir>${project.build.directory}/surefire</xmlOutputDir>
        </systemPropertyVariables>
    </configuration>
</plugin>`

How can I read the contents of an URL with Python?

None of these answers are very good for Python 3 (tested on latest version at the time of this post).

This is how you do it...

import urllib.request

try:
   with urllib.request.urlopen('http://www.python.org/') as f:
      print(f.read().decode('utf-8'))
except urllib.error.URLError as e:
   print(e.reason)

The above is for contents that return 'utf-8'. Remove .decode('utf-8') if you want python to "guess the appropriate encoding."

Documentation: https://docs.python.org/3/library/urllib.request.html#module-urllib.request

openssl s_client using a proxy

Even with openssl v1.1.0 I had some problems passing our proxy, e.g. s_client: HTTP CONNECT failed: 400 Bad Request That forced me to write a minimal Java-class to show the SSL-Handshake

    public static void main(String[] args) throws IOException, URISyntaxException {
    HttpHost proxy = new HttpHost("proxy.my.company", 8080);
    DefaultProxyRoutePlanner routePlanner = new DefaultProxyRoutePlanner(proxy);
    CloseableHttpClient httpclient = HttpClients.custom()
            .setRoutePlanner(routePlanner)
            .build();
    URI uri = new URIBuilder()
            .setScheme("https")
            .setHost("www.myhost.com")
            .build();
    HttpGet httpget = new HttpGet(uri);
    httpclient.execute(httpget);
}

With following dependency:

    <dependency>
        <groupId>org.apache.httpcomponents</groupId>
        <artifactId>httpclient</artifactId>
        <version>4.5.2</version>
        <type>jar</type>
    </dependency>

you can run it with Java SSL Logging turned on

This should produce nice output like

trustStore provider is :
init truststore
adding as trusted cert:
  Subject: CN=Equifax Secure Global eBusiness CA-1, O=Equifax Secure Inc., C=US
  Issuer:  CN=Equifax Secure Global eBusiness CA-1, O=Equifax Secure Inc., C=US
  Algorithm: RSA; Serial number: 0xc3517
  Valid from Mon Jun 21 06:00:00 CEST 1999 until Mon Jun 22 06:00:00 CEST 2020

adding as trusted cert:
  Subject: CN=SecureTrust CA, O=SecureTrust Corporation, C=US
  Issuer:  CN=SecureTrust CA, O=SecureTrust Corporation, C=US
(....)

Java: Reading a file into an array

Apache Commons I/O provides FileUtils#readLines(), which should be fine for all but huge files: http://commons.apache.org/io/api-release/index.html. The 2.1 distribution includes FileUtils.lineIterator(), which would be suitable for large files. Google's Guava libraries include similar utilities.

jQuery - Appending a div to body, the body is the object?

var $div = $('<div />').appendTo('body');
$div.attr('id', 'holdy');

Error during installing HAXM, VT-X not working

Here is an example how to do it for LENOVA or similar PC:

  1. Start the machine.
  2. Press F2 to enter BIOS.
  3. Security-> System Security
  4. Enable Virtualization Technology (VTx) and Virtualization Technology Directed I/O (VTd).
  5. Save and restart the machine

How exactly does the android:onClick XML attribute differ from setOnClickListener?

When I saw the top answer, it made me realize that my problem was not putting the parameter (View v) on the fancy method:

public void myFancyMethod(View v) {}

When trying to access it from the xml, one should use

android:onClick="myFancyMethod"/>

Hope that helps someone.

What does -Xmn jvm option stands for

From GC Performance Tuning training documents of Oracle:

-Xmn[size]: Size of young generation heap space.

Applications with emphasis on performance tend to use -Xmn to size the young generation, because it combines the use of -XX:MaxNewSize and -XX:NewSize and almost always explicitly sets -XX:PermSize and -XX:MaxPermSize to the same value.

In short, it sets the NewSize and MaxNewSize values of New generation to the same value.

Set Text property of asp:label in Javascript PROPER way

Since you have updated your label client side, you'll need a post-back in order for you're server side code to reflect the changes.

If you do not know how to do this, here is how I've gone about it in the past.

Create a hidden field:

<input type="hidden" name="__EVENTTARGET" id="__EVENTTARGET" value="" />

Create a button that has both client side and server side functions attached to it. You're client side function will populate your hidden field, and the server side will read it. Be sure you're client side is being called first.

<asp:Button ID="_Submit" runat="server" Text="Submit Button" OnClientClick="TestSubmit();" OnClick="_Submit_Click" />

Javascript Client Side Function:

function TestSubmit() {
              try {

             var message = "Message to Pass";
             document.getElementById('__EVENTTARGET').value = message;

           } catch (err) {
              alert(err.message);

          }

      }

C# Server Side Function

protected void _Submit_Click(object sender, EventArgs e)
{
     // Hidden Value after postback
     string hiddenVal= Request.Form["__EVENTTARGET"];
}

Hope this helps!

equivalent of vbCrLf in c#

I think that "\r\n" should work fine

Deleting array elements in JavaScript - delete vs splice

Array.remove() Method

John Resig, creator of jQuery created a very handy Array.remove method that I always use it in my projects.

// Array Remove - By John Resig (MIT Licensed)
Array.prototype.remove = function(from, to) {
  var rest = this.slice((to || from) + 1 || this.length);
  this.length = from < 0 ? this.length + from : from;
  return this.push.apply(this, rest);
};

and here's some examples of how it could be used:

// Remove the second item from the array
array.remove(1);
// Remove the second-to-last item from the array
array.remove(-2);
// Remove the second and third items from the array
array.remove(1,2);
// Remove the last and second-to-last items from the array
array.remove(-2,-1);

John's website

How do I print the percent sign(%) in c

Your problem is that you have to change:

printf("%"); 

to

printf("%%");

Or you could use ASCII code and write:

printf("%c", 37);

:)

What does the star operator mean, in a function call?

I find this particularly useful for when you want to 'store' a function call.

For example, suppose I have some unit tests for a function 'add':

def add(a, b): return a + b
tests = { (1,4):5, (0, 0):0, (-1, 3):3 }
for test, result in tests.items():
    print 'test: adding', test, '==', result, '---', add(*test) == result

There is no other way to call add, other than manually doing something like add(test[0], test[1]), which is ugly. Also, if there are a variable number of variables, the code could get pretty ugly with all the if-statements you would need.

Another place this is useful is for defining Factory objects (objects that create objects for you). Suppose you have some class Factory, that makes Car objects and returns them. You could make it so that myFactory.make_car('red', 'bmw', '335ix') creates Car('red', 'bmw', '335ix'), then returns it.

def make_car(*args):
    return Car(*args)

This is also useful when you want to call a superclass' constructor.

How to get the type of T from a member of a generic class or method?

If you want to know a property's underlying type, try this:

propInfo.PropertyType.UnderlyingSystemType.GenericTypeArguments[0]

Get unique values from arraylist in java

When I was doing the same query, I had hard time adjusting the solutions to my case, though all the previous answers have good insights.

Here is a solution when one has to acquire a list of unique objects, NOT strings. Let's say, one has a list of Record object. Record class has only properties of type String, NO property of type int. Here implementing hashCode() becomes difficult as hashCode() needs to return an int.

The following is a sample Record Class.

public class Record{

    String employeeName;
    String employeeGroup;

    Record(String name, String group){  
        employeeName= name;
        employeeGroup = group;    
    }
    public String getEmployeeName(){
        return employeeName;
    }
    public String getEmployeeGroup(){
        return employeeGroup;
    }

  @Override
    public boolean equals(Object o){
         if(o instanceof Record){
            if (((Record) o).employeeGroup.equals(employeeGroup) &&
                  ((Record) o).employeeName.equals(employeeName)){
                return true;
            }
         }
         return false;
    }

    @Override
    public int hashCode() { //this should return a unique code
        int hash = 3; //this could be anything, but I would chose a prime(e.g. 5, 7, 11 )
        //again, the multiplier could be anything like 59,79,89, any prime
        hash = 89 * hash + Objects.hashCode(this.employeeGroup); 
        return hash;
    }

As suggested earlier by others, the class needs to override both the equals() and the hashCode() method to be able to use HashSet.

Now, let's say, the list of Records is allRecord(List<Record> allRecord).

Set<Record> distinctRecords = new HashSet<>();

for(Record rc: allRecord){
    distinctRecords.add(rc);
}

This will only add the distinct Records to the Hashset, distinctRecords.

Hope this helps.

What is the easiest way to remove the first character from a string?

For example : a = "One Two Three"

1.9.2-p290 > a = "One Two Three"
 => "One Two Three" 

1.9.2-p290 > a = a[1..-1]
 => "ne Two Three" 

1.9.2-p290 > a = a[1..-1]
 => "e Two Three" 

1.9.2-p290 > a = a[1..-1]
 => " Two Three" 

1.9.2-p290 > a = a[1..-1]
 => "Two Three" 

1.9.2-p290 > a = a[1..-1]
 => "wo Three" 

In this way you can remove one by one first character of the string.

RegEx for validating an integer with a maximum length of 10 characters

Don't forget that integers can be negative:

^\s*-?[0-9]{1,10}\s*$

Here's the meaning of each part:

  • ^: Match must start at beginning of string
  • \s: Any whitespace character
    • *: Occurring zero or more times
  • -: The hyphen-minus character, used to denote a negative integer
    • ?: May or may not occur
  • [0-9]: Any character whose ASCII code (or Unicode code point) is between '0' and '9'
    • {1,10}: Occurring at least one, but not more than ten times
  • \s: Any whitespace character
    • *: Occurring zero or more times
  • $: Match must end at end of string

This ignores leading and trailing whitespace and would be more complex if you consider commas acceptable or if you need to count the minus sign as one of the ten allowed characters.

What is external linkage and internal linkage?

In C++

Any variable at file scope and that is not nested inside a class or function, is visible throughout all translation units in a program. This is called external linkage because at link time the name is visible to the linker everywhere, external to that translation unit.

Global variables and ordinary functions have external linkage.

Static object or function name at file scope is local to translation unit. That is called as Internal Linkage

Linkage refers only to elements that have addresses at link/load time; thus, class declarations and local variables have no linkage.

Import CSV to mysql table

As others have mentioned, the load data local infile works just fine. I tried the php script that Hawkee posted, but didnt work for me. Rather than debug it, here's what i did:

1) copy/paste the header row of the CSV file into a txt file and edit with emacs. add a comma and CR between each field to get each on on it's own line.
2) Save that file as FieldList.txt
3) edit the file to include defns for each field (most were varchar, but quite a few were int(x). Add create table tablename ( to the beginning of the file and ) to the end of the file. Save it as CreateTable.sql
4) start mysql client with input from the Createtable.sql file to create the table
5) start mysql client, copy/paste in most of the 'LOAD DATA INFILE' command subsituting my table name and csv file name. Paste in the FieldList.txt file. Be sure to include the 'IGNORE 1 LINES' before pasting in the field list

Sounds like a lot of work, but easy with emacs.....

Get first row of dataframe in Python Pandas based on criteria

For the point that 'returns the value as soon as you find the first row/record that meets the requirements and NOT iterating other rows', the following code would work:

def pd_iter_func(df):
    for row in df.itertuples():
        # Define your criteria here
        if row.A > 4 and row.B > 3:
            return row

It is more efficient than Boolean Indexing when it comes to a large dataframe.

To make the function above more applicable, one can implements lambda functions:

def pd_iter_func(df: DataFrame, criteria: Callable[[NamedTuple], bool]) -> Optional[NamedTuple]:
    for row in df.itertuples():
        if criteria(row):
            return row

pd_iter_func(df, lambda row: row.A > 4 and row.B > 3)

As mentioned in the answer to the 'mirror' question, pandas.Series.idxmax would also be a nice choice.

def pd_idxmax_func(df, mask):
    return df.loc[mask.idxmax()]

pd_idxmax_func(df, (df.A > 4) & (df.B > 3))

Passing a variable from one php include file to another: global vs. not

This is all you have to do:

In front.inc

global $name;
$name = 'james';

HTML5 video (mp4 and ogv) problems in Safari and Firefox - but Chrome is all good

The HTTP Content-Type for .ogg should be application/ogg (video/ogg for .ogv) and for .mp4 it should be video/mp4. You can check using the Web Sniffer.

stop all instances of node.js server

You can use lsof get the process that has bound to the required port.

Unfortunately the flags seem to be different depending on system, but on Mac OS X you can run

lsof -Pi | grep LISTEN

For example, on my machine I get something like:

mongod     8662 jacob    6u  IPv4 0x17ceae4e0970fbe9      0t0  TCP localhost:27017 (LISTEN)
mongod     8662 jacob    7u  IPv4 0x17ceae4e0f9c24b1      0t0  TCP localhost:28017 (LISTEN)
memcached  8680 jacob   17u  IPv4 0x17ceae4e0971f7d1      0t0  TCP *:11211 (LISTEN)
memcached  8680 jacob   18u  IPv6 0x17ceae4e0bdf6479      0t0  TCP *:11211 (LISTEN)
mysqld     9394 jacob   10u  IPv4 0x17ceae4e080c4001      0t0  TCP *:3306 (LISTEN)
redis-ser 75429 jacob    4u  IPv4 0x17ceae4e1ba8ea59      0t0  TCP localhost:6379 (LISTEN)

The second number is the PID and the port they're listening to is on the right before "(LISTEN)". Find the rogue PID and kill -9 $PID to terminate with extreme prejudice.

Scanner only reads first word instead of line

Javadoc to the rescue :

A Scanner breaks its input into tokens using a delimiter pattern, which by default matches whitespace

nextLine is probably the method you should use.

In Python try until no error

what about the retrying library on pypi? I have been using it for a while and it does exactly what I want and more (retry on error, retry when None, retry with timeout). Below is example from their website:

import random
from retrying import retry

@retry
def do_something_unreliable():
    if random.randint(0, 10) > 1:
        raise IOError("Broken sauce, everything is hosed!!!111one")
    else:
        return "Awesome sauce!"

print do_something_unreliable()

Print a file, skipping the first X lines, in Bash

You'll need tail. Some examples:

$ tail great-big-file.log
< Last 10 lines of great-big-file.log >

If you really need to SKIP a particular number of "first" lines, use

$ tail -n +<N+1> <filename>
< filename, excluding first N lines. >

That is, if you want to skip N lines, you start printing line N+1. Example:

$ tail -n +11 /tmp/myfile
< /tmp/myfile, starting at line 11, or skipping the first 10 lines. >

If you want to just see the last so many lines, omit the "+":

$ tail -n <N> <filename>
< last N lines of file. >

How to set zoom level in google map

For zooming your map two level then just add this small code of line map.setZoom(map.getZoom() + 2);

ERROR in The Angular Compiler requires TypeScript >=3.1.1 and <3.2.0 but 3.2.1 was found instead

npm install typescript@">=3.1.1 <3.3.0" --save-dev --save-exact
rm -rf node_modules
npm install

How can I set multiple CSS styles in JavaScript?

Don't think it is possible as such.

But you could create an object out of the style definitions and just loop through them.

var allMyStyle = {
  fontsize: '12px',
  left: '200px',
  top: '100px'
};

for (i in allMyStyle)
  document.getElementById("myElement").style[i] = allMyStyle[i];

To develop further, make a function for it:

function setStyles(element, styles) {
  for (i in styles)
    element.style[i] = styles[i];
}

setStyles(document.getElementById("myElement"), allMyStyle);

How to replace text of a cell based on condition in excel

You can use the Conditional Formatting to replace text and NOT effect any formulas. Simply go to the Rule's format where you will see Number, Font, Border and Fill.
Go to the Number tab and select CUSTOM. Then simply type where it says TYPE: what you want to say in QUOTES.

Example.. "OTHER"

AlertDialog.Builder with custom layout and EditText; cannot access view

editText is a part of alertDialog layout so Just access editText with reference of alertDialog

EditText editText = (EditText) alertDialog.findViewById(R.id.label_field);

Update:

Because in code line dialogBuilder.setView(inflater.inflate(R.layout.alert_label_editor, null));

inflater is Null.

update your code like below, and try to understand the each code line

AlertDialog.Builder dialogBuilder = new AlertDialog.Builder(this);
// ...Irrelevant code for customizing the buttons and title
LayoutInflater inflater = this.getLayoutInflater();
View dialogView = inflater.inflate(R.layout.alert_label_editor, null);
dialogBuilder.setView(dialogView);

EditText editText = (EditText) dialogView.findViewById(R.id.label_field);
editText.setText("test label");
AlertDialog alertDialog = dialogBuilder.create();
alertDialog.show();

Update 2:

As you are using View object created by Inflater to update UI components else you can directly use setView(int layourResId) method of AlertDialog.Builder class, which is available from API 21 and onwards.

Populate unique values into a VBA array from Excel

The VBA script below looks for all unique values from cell B5 all the way down to the very last cell in column B… $B$1048576. Once it is found, they are stored in the array (objDict).

Private Const SHT_MASTER = “MASTER”
Private Const SHT_INST_INDEX = “InstrumentIndex”

Sub UniqueList()
    Dim Xyber
    Dim objDict As Object
    Dim lngRow As Long

    Sheets(SHT_MASTER).Activate
    Xyber = Application.Transpose(Sheets(SHT_MASTER).Range([b5], Cells(Rows.count, “B”).End(xlUp)))
    Sheets(SHT_INST_INDEX).Activate
    Set objDict = CreateObject(“Scripting.Dictionary”)
    For lngRow = 1 To UBound(Xyber, 1)
    If Len(Xyber(lngRow)) > 0 Then objDict(Xyber(lngRow)) = 1
    Next
    Sheets(SHT_INST_INDEX).Range(“B1:B” & objDict.count) = Application.Transpose(objDict.keys)
End Sub

I have tested and documented with some screenshots of the this solution. Here is the link where you can find it....

http://xybernetics.com/techtalk/excelvba-getarrayofuniquevaluesfromspecificcolumn/

Google Maps JavaScript API RefererNotAllowedMapError

Check you have the correct APIS enabled as well.

I tried all of the above, asterisks, domain tlds, forward slashes, backslashes and everything, even in the end only entering one url as a last hope.

All of this did not work and finally I realised that Google also requires that you specify now which API's you want to use (see screenshot)

enter image description here

I did not have ones I needed enabled (for me that was Maps JavaScript API)

Once I enabled it, all worked fine using:

http://www.example.com/*

I hope that helps someone! :)

Check OS version in Swift?

I made helper functions that were transferred from the below link into swift:

How can we programmatically detect which iOS version is device running on?

func SYSTEM_VERSION_EQUAL_TO(version: String) -> Bool {
    return UIDevice.currentDevice().systemVersion.compare(version,
        options: NSStringCompareOptions.NumericSearch) == NSComparisonResult.OrderedSame
}

func SYSTEM_VERSION_GREATER_THAN(version: String) -> Bool {
    return UIDevice.currentDevice().systemVersion.compare(version,
        options: NSStringCompareOptions.NumericSearch) == NSComparisonResult.OrderedDescending
}

func SYSTEM_VERSION_GREATER_THAN_OR_EQUAL_TO(version: String) -> Bool {
    return UIDevice.currentDevice().systemVersion.compare(version,
        options: NSStringCompareOptions.NumericSearch) != NSComparisonResult.OrderedAscending
}

func SYSTEM_VERSION_LESS_THAN(version: String) -> Bool {
    return UIDevice.currentDevice().systemVersion.compare(version,
        options: NSStringCompareOptions.NumericSearch) == NSComparisonResult.OrderedAscending
}

func SYSTEM_VERSION_LESS_THAN_OR_EQUAL_TO(version: String) -> Bool {
    return UIDevice.currentDevice().systemVersion.compare(version,
        options: NSStringCompareOptions.NumericSearch) != NSComparisonResult.OrderedDescending
}

It can be used like so:

SYSTEM_VERSION_LESS_THAN_OR_EQUAL_TO("7.0")

Swift 4.2

func SYSTEM_VERSION_EQUAL_TO(version: String) -> Bool {
    return UIDevice.current.systemVersion.compare(version, options: .numeric) == .orderedSame
}

func SYSTEM_VERSION_GREATER_THAN(version: String) -> Bool {
    return UIDevice.current.systemVersion.compare(version, options: .numeric) == .orderedDescending
}

func SYSTEM_VERSION_GREATER_THAN_OR_EQUAL_TO(version: String) -> Bool {
    return UIDevice.current.systemVersion.compare(version, options: .numeric) != .orderedAscending
}

func SYSTEM_VERSION_LESS_THAN(version: String) -> Bool {
    return UIDevice.current.systemVersion.compare(version, options: .numeric) == .orderedAscending
}

func SYSTEM_VERSION_LESS_THAN_OR_EQUAL_TO(version: String) -> Bool {
    return UIDevice.current.systemVersion.compare(version, options: .numeric) != .orderedDescending
}

How to stretch a table over multiple pages

You should \usepackage{longtable}.

How to call a method in MainActivity from another class?

Use this code in sub Fragment of MainActivity to call the method on it.

((MainActivity) getActivity()).startChronometer();

How do I declare and initialize an array in Java?

The following shows the declaration of an array, but the array is not initialized:

 int[] myIntArray = new int[3];

The following shows the declaration as well as initialization of the array:

int[] myIntArray = {1,2,3};

Now, the following also shows the declaration as well as initialization of the array:

int[] myIntArray = new int[]{1,2,3};

But this third one shows the property of anonymous array-object creation which is pointed by a reference variable "myIntArray", so if we write just "new int[]{1,2,3};" then this is how anonymous array-object can be created.

If we just write:

int[] myIntArray;

this is not declaration of array, but the following statement makes the above declaration complete:

myIntArray=new int[3];

Hide password with "•••••••" in a textField

You can do this by using properties of textfield from Attribute inspector

Tap on Your Textfield from storyboard and go to Attribute inspector , and just check the checkbox of "Secure Text Entry" SS is added for graphical overview to achieve same

Generate a dummy-variable

I use such a function (for data.table):

# Ta funkcja dla obiektu data.table i zmiennej var.name typu factor tworzy dummy variables o nazwach "var.name: (level1)"
factorToDummy <- function(dtable, var.name){
  stopifnot(is.data.table(dtable))
  stopifnot(var.name %in% names(dtable))
  stopifnot(is.factor(dtable[, get(var.name)]))

  dtable[, paste0(var.name,": ",levels(get(var.name)))] -> new.names
  dtable[, (new.names) := transpose(lapply(get(var.name), FUN = function(x){x == levels(get(var.name))})) ]

  cat(paste("\nDodano zmienne dummy: ", paste0(new.names, collapse = ", ")))
}

Usage:

data <- data.table(data)
data[, x:= droplevels(x)]
factorToDummy(data, "x")

Which loop is faster, while or for?

In C#, the For loop is slightly faster.

For loop average about 2.95 to 3.02 ms.

The While loop averaged about 3.05 to 3.37 ms.

Quick little console app to prove:

 class Program
    {
        static void Main(string[] args)
        {
            int max = 1000000000;
            Stopwatch stopWatch = new Stopwatch();

            if (args.Length == 1 && args[0].ToString() == "While")
            {
                Console.WriteLine("While Loop: ");
                stopWatch.Start();
                WhileLoop(max);
                stopWatch.Stop();
                DisplayElapsedTime(stopWatch.Elapsed);
            }
            else
            {
                Console.WriteLine("For Loop: ");
                stopWatch.Start();
                ForLoop(max);
                stopWatch.Stop();
                DisplayElapsedTime(stopWatch.Elapsed);
            }
        }

        private static void WhileLoop(int max)
        {
            int i = 0;
            while (i <= max)
            {
                //Console.WriteLine(i);
                i++;
            };
        }

        private static void ForLoop(int max)
        {
            for (int i = 0; i <= max; i++)
            {
                //Console.WriteLine(i);
            }
        }

        private static void DisplayElapsedTime(TimeSpan ts)
        {
            // Format and display the TimeSpan value.
            string elapsedTime = String.Format("{0:00}:{1:00}:{2:00}.{3:00}",
                ts.Hours, ts.Minutes, ts.Seconds,
                ts.Milliseconds / 10);
            Console.WriteLine(elapsedTime, "RunTime");
        }
    }

nginx missing sites-available directory

If you'd prefer a more direct approach, one that does NOT mess with symlinking between /etc/nginx/sites-available and /etc/nginx/sites-enabled, do the following:

  1. Locate your nginx.conf file. Likely at /etc/nginx/nginx.conf
  2. Find the http block.
  3. Somewhere in the http block, write include /etc/nginx/conf.d/*.conf; This tells nginx to pull in any files in the conf.d directory that end in .conf. (I know: it's weird that a directory can have a . in it.)
  4. Create the conf.d directory if it doesn't already exist (per the path in step 3). Be sure to give it the right permissions/ownership. Likely root or www-data.
  5. Move or copy your separate config files (just like you have in /etc/nginx/sites-available) into the directory conf.d.
  6. Reload or restart nginx.
  7. Eat an ice cream cone.

Any .conf files that you put into the conf.d directory from here on out will become active as long as you reload/restart nginx after.

Note: You can use the conf.d and sites-enabled + sites-available method concurrently if you wish. I like to test on my dev box using conf.d. Feels faster than symlinking and unsymlinking.

Missing artifact com.microsoft.sqlserver:sqljdbc4:jar:4.0

You can use another driver

<dependency>
    <groupId>net.sourceforge.jtds</groupId>
    <artifactId>jtds</artifactId>
    <version>1.3.1</version>
</dependency>

and in xml

<bean id="idNameDb" class="org.springframework.jdbc.datasource.DriverManagerDataSource">
        <property name="driverClassName" value="net.sourceforge.jtds.jdbc.Driver" />
        <property name="url" value="jdbc:jtds:sqlserver://[ip]:1433;DatabaseName=[name]" />
        <property name="username" value="user" />
        <property name="password" value="password" />
</bean>

What does it mean when Statement.executeUpdate() returns -1?

I haven't seen this anywhere, either, but my instinct would be that this means that the IF prevented the whole statement from executing.

Try to run the statement with a database where the IF passes.

Also check if there are any triggers involved which might change the result.

[EDIT] When the standard says that this function should never return -1, that doesn't enforce this. Java doesn't have pre and post conditions. A JDBC driver could return a random number and there was no way to stop it.

If it's important to know why this happens, run the statement against different database until you have tried all execution paths (i.e. one where the IF returns false and one where it returns true).

If it's not that important, mark it off as a "clever trick" by a Microsoft engineer and remember how much you liked it when you feel like being clever yourself next time.

How do I update a Linq to SQL dbml file?

In the case of stored procedure update, you should delete it from the .dbml file and reinsert it again. But if the stored procedure have two paths (ex: if something; display some columns; else display some other columns), make sure the two paths have the same columns aliases!!! Otherwise only the first path columns will exist.

Set default option in mat-select

It took me several hours to figure out this until the similarity of the datatypes between the array and that of the default value worked for me...

PySpark: withColumn() with two conditions and three outcomes

There are a few efficient ways to implement this. Let's start with required imports:

from pyspark.sql.functions import col, expr, when

You can use Hive IF function inside expr:

new_column_1 = expr(
    """IF(fruit1 IS NULL OR fruit2 IS NULL, 3, IF(fruit1 = fruit2, 1, 0))"""
)

or when + otherwise:

new_column_2 = when(
    col("fruit1").isNull() | col("fruit2").isNull(), 3
).when(col("fruit1") == col("fruit2"), 1).otherwise(0)

Finally you could use following trick:

from pyspark.sql.functions import coalesce, lit

new_column_3 = coalesce((col("fruit1") == col("fruit2")).cast("int"), lit(3))

With example data:

df = sc.parallelize([
    ("orange", "apple"), ("kiwi", None), (None, "banana"), 
    ("mango", "mango"), (None, None)
]).toDF(["fruit1", "fruit2"])

you can use this as follows:

(df
    .withColumn("new_column_1", new_column_1)
    .withColumn("new_column_2", new_column_2)
    .withColumn("new_column_3", new_column_3))

and the result is:

+------+------+------------+------------+------------+
|fruit1|fruit2|new_column_1|new_column_2|new_column_3|
+------+------+------------+------------+------------+
|orange| apple|           0|           0|           0|
|  kiwi|  null|           3|           3|           3|
|  null|banana|           3|           3|           3|
| mango| mango|           1|           1|           1|
|  null|  null|           3|           3|           3|
+------+------+------------+------------+------------+

how to check if string value is in the Enum list?

I know this is an old thread, but here's a slightly different approach using attributes on the Enumerates and then a helper class to find the enumerate that matches.

This way you could have multiple mappings on a single enumerate.

public enum Age
{
    [Metadata("Value", "New_Born")]
    [Metadata("Value", "NewBorn")]
    New_Born = 1,
    [Metadata("Value", "Toddler")]
    Toddler = 2,
    [Metadata("Value", "Preschool")]
    Preschool = 4,
    [Metadata("Value", "Kindergarten")]
    Kindergarten = 8
}

With my helper class like this

public static class MetadataHelper
{
    public static string GetFirstValueFromMetaDataAttribute<T>(this T value, string metaDataDescription)
    {
        return GetValueFromMetaDataAttribute(value, metaDataDescription).FirstOrDefault();
    }

    private static IEnumerable<string> GetValueFromMetaDataAttribute<T>(T value, string metaDataDescription)
    {
        var attribs =
            value.GetType().GetField(value.ToString()).GetCustomAttributes(typeof (MetadataAttribute), true);
        return attribs.Any()
            ? (from p in (MetadataAttribute[]) attribs
                where p.Description.ToLower() == metaDataDescription.ToLower()
                select p.MetaData).ToList()
            : new List<string>();
    }

    public static List<T> GetEnumeratesByMetaData<T>(string metadataDescription, string value)
    {
        return
            typeof (T).GetEnumValues().Cast<T>().Where(
                enumerate =>
                    GetValueFromMetaDataAttribute(enumerate, metadataDescription).Any(
                        p => p.ToLower() == value.ToLower())).ToList();
    }

    public static List<T> GetNotEnumeratesByMetaData<T>(string metadataDescription, string value)
    {
        return
            typeof (T).GetEnumValues().Cast<T>().Where(
                enumerate =>
                    GetValueFromMetaDataAttribute(enumerate, metadataDescription).All(
                        p => p.ToLower() != value.ToLower())).ToList();
    }

}

you can then do something like

var enumerates = MetadataHelper.GetEnumeratesByMetaData<Age>("Value", "New_Born");

And for completeness here is the attribute:

 [AttributeUsage(AttributeTargets.Field, Inherited = false, AllowMultiple = true)]
public class MetadataAttribute : Attribute
{
    public MetadataAttribute(string description, string metaData = "")
    {
        Description = description;
        MetaData = metaData;
    }

    public string Description { get; set; }
    public string MetaData { get; set; }
}

PDO error message?

From the manual:

If the database server successfully prepares the statement, PDO::prepare() returns a PDOStatement object. If the database server cannot successfully prepare the statement, PDO::prepare() returns FALSE or emits PDOException (depending on error handling).

The prepare statement likely caused an error because the db would be unable to prepare the statement. Try testing for an error immediately after you prepare your query and before you execute it.

$qry = '
    INSERT INTO non-existant-table (id, score) 
    SELECT id, 40 
    FROM another-non-existant-table
    WHERE description LIKE "%:search_string%"
    AND available = "yes"
    ON DUPLICATE KEY UPDATE score = score + 40
';
$sth = $this->pdo->prepare($qry);
print_r($this->pdo->errorInfo());

When do you use varargs in Java?

Varargs is the feature added in java version 1.5.

Why to use this?

  1. What if, you don't know the number of arguments to pass for a method?
  2. What if, you want to pass unlimited number of arguments to a method?

How this works?

It creates an array with the given arguments & passes the array to the method.

Example :

public class Solution {



    public static void main(String[] args) {
        add(5,7);
        add(5,7,9);
    }

    public static void add(int... s){
        System.out.println(s.length);
        int sum=0;
        for(int num:s)
            sum=sum+num;
        System.out.println("sum is "+sum );
    }

}

Output :

2

sum is 12

3

sum is 21

How to convert MySQL time to UNIX timestamp using PHP?

$time_PHP = strtotime( $datetime_SQL );

Chrome violation : [Violation] Handler took 83ms of runtime

It seems you have found your solution, but still it will be helpful to others, on this page on point based on Chrome 59.

4.Note the red triangle in the top-right of the Animation Frame Fired event. Whenever you see a red triangle, it's a warning that there may be an issue related to this event.

If you hover on these triangle you can see those are the violation handler errors and as per point 4. yes there is some issue related to that event.

A warning - comparison between signed and unsigned integer expressions

It is usually a good idea to declare variables as unsigned or size_t if they will be compared to sizes, to avoid this issue. Whenever possible, use the exact type you will be comparing against (for example, use std::string::size_type when comparing with a std::string's length).

Compilers give warnings about comparing signed and unsigned types because the ranges of signed and unsigned ints are different, and when they are compared to one another, the results can be surprising. If you have to make such a comparison, you should explicitly convert one of the values to a type compatible with the other, perhaps after checking to ensure that the conversion is valid. For example:

unsigned u = GetSomeUnsignedValue();
int i = GetSomeSignedValue();

if (i >= 0)
{
    // i is nonnegative, so it is safe to cast to unsigned value
    if ((unsigned)i >= u)
        iIsGreaterThanOrEqualToU();
    else
        iIsLessThanU();
}
else
{
    iIsNegative();
}

When to Redis? When to MongoDB?

I would say, it depends on kind of dev team you are and your application needs.

For example, if you require a lot of querying, that mostly means it would be more work for your developers to use Redis, where your data might be stored in variety of specialized data structures, customized for each type of object for efficiency. In MongoDB the same queries might be easier because the structure is more consistent across your data. On the other hand, in Redis, sheer speed of the response to those queries is the payoff for the extra work of dealing with the variety of structures your data might be stored with.

MongoDB offers simplicity, much shorter learning curve for developers with traditional DB and SQL experience. However, Redis's non-traditional approach requires more effort to learn, but greater flexibility.

Eg. A cache layer can probably be better implemented in Redis. For more schema-able data, MongoDB is better. [Note: both MongoDB and Redis are technically schemaless]

If you ask me, my personal choice is Redis for most requirements.

Lastly, I hope by now you have seen http://antirez.com/post/MongoDB-and-Redis.html

Export a list into a CSV or TXT file in R

You can simply wrap your list as a data.frame (data.frame is in fact a special kind of list). Here is an example:

mylist = list() 
mylist[["a"]] = 1:10 
mylist[["b"]] = letters[1:10]
write.table(as.data.frame(mylist),file="mylist.csv", quote=F,sep=",",row.names=F)

or alternatively you can use write.csv (a wrapper around write.table). For the conversion of the list , you can use both as.data.frame(mylist) and data.frame(mylist).

To help in making a reproducible example, you can use functions like dput on your data.

HTML Table cellspacing or padding just top / bottom

CSS?

td {
  padding-top: 2px;
  padding-bottom: 2px;
}

Youtube iframe wmode issue

&wmode=opaque didn't work for me (chrome 10) but &amp;wmode=transparent cleared the issue right up.

What is a None value?

largest=none
smallest =none 
While True :
          num =raw_input ('enter a number ') 
          if num =="done ": break 
          try :
           inp =int (inp) 
          except:
              Print'Invalid input' 
           if largest is none :
               largest=inp
           elif inp>largest:
                largest =none 
           print 'maximum', largest

          if smallest is none:
               smallest =none
          elif inp<smallest :
               smallest =inp
          print 'minimum', smallest 

print 'maximum, minimum, largest, smallest 

Mockito: InvalidUseOfMatchersException

It might help some one in the future: Mockito doesn't support mocking of 'final' methods (right now). It gave me the same InvalidUseOfMatchersException.

The solution for me was to put the part of the method that didn't have to be 'final' in a separate, accessible and overridable method.

Review the Mockito API for your use case.

How to get file size in Java

Use the length() method in the File class. From the javadocs:

Returns the length of the file denoted by this abstract pathname. The return value is unspecified if this pathname denotes a directory.

UPDATED Nowadays we should use the Files.size() method:

Paths path = Paths.get("/path/to/file");
long size = Files.size(path);

For the second part of the question, straight from File's javadocs:

  • getUsableSpace() Returns the number of bytes available to this virtual machine on the partition named by this abstract pathname

  • getTotalSpace() Returns the size of the partition named by this abstract pathname

  • getFreeSpace() Returns the number of unallocated bytes in the partition named by this abstract path name

How to send email from SQL Server?

You can send email natively from within SQL Server using Database Mail. This is a great tool for notifying sysadmins about errors or other database events. You could also use it to send a report or an email message to an end user. The basic syntax for this is:

EXEC msdb.dbo.sp_send_dbmail  
@recipients='[email protected]',
@subject='Testing Email from SQL Server',
@body='<p>It Worked!</p><p>Email sent successfully</p>',
@body_format='HTML',
@from_address='Sender Name <[email protected]>',
@reply_to='[email protected]'

Before use, Database Mail must be enabled using the Database Mail Configuration Wizard, or sp_configure. A database or Exchange admin might need to help you configure this. See http://msdn.microsoft.com/en-us/library/ms190307.aspx and http://www.codeproject.com/Articles/485124/Configuring-Database-Mail-in-SQL-Server for more information.

google-services.json for different productFlavors

Simplifying what @Scotti said. You need to create Multiples apps with different package name for a particular Project depending on the product flavor.

Suppose your Project is ABC having different product flavors X,Y where X has a package name com.x and Y has a package name com.y then in the firebase console you need to create a project ABC in which you need to create 2 apps with the package names com.x and com.y. Then you need to download the google-services.json file in which there will be 2 client-info objects which will contain those pacakges and you will be good to go.

Snippet of the json would be something like this

{
  "client": [
    {
      "client_info": {
        "android_client_info": {
          "package_name": "com.x"
        }

    {
      "client_info": {
        "android_client_info": {
          "package_name": "com.y"
        }
      ]

    }

Resize command prompt through commands

Although the answers given here can be used to temporarily change window size, they don't seem to affect font size (at least not on my PC). I have an alternative way. I don't know if this what you're looking for but if you want to make changes automatically/permanently to Console font/window size, you can always do a script that edits the registry:

HKEY_CURRENT_USER\Console
HKEY_CURRENT_USER\Console\%%SystemRoot%%_system32_cmd.exe
HKEY_CURRENT_USER\Console\%%SystemRoot%%_system32_WindowsPowerShell_v1.0_powershell.exe

Those keys deal with the consoles that come up when your run a script or press shift and select "open command prompt here". The Command Prompt entry in your start menu does not use the registry to store it's preferences but stores the prefs in the shortcut itself.

I have a monitor that I can run in 720p native or 1440p supersampling. I needed a quick way to change my console's font/window size, so I made these scripts. These scripts do two things: (1) change the font/window sizes in the registry and (2) swap out the shortcuts in the Start menu with ones that have a different window and font size. I basically made two sets of copies of the Command Prompt and Power Shell shortcuts and stored them in Documents. One set of shortcuts was configured with Consolas font size at 16 for my monitor is in 720p (called it "Command Prompt.720pRes.lnk") and another version of the same shortcut was configure with font size at 36 (called it "Command Prompt.HighRes.lnk"). The script will copy from the set I want to use to overwrite the Start menu one.

console-1440p.cmd:

::Assign New Window and Font Size for Windows Command Prompt
set CMDpNewFont=00240000
set CMDpNewWindowSize=000f0078
set commandPromptLinkFlag=highRes



 ::Make temporary .reg file to resize command console

>%temp%\consoleSIZEchanger.reg ECHO Windows Registry Editor Version 5.00
>>%temp%\consoleSIZEchanger.reg ECHO.
>>%temp%\consoleSIZEchanger.reg ECHO [HKEY_CURRENT_USER\Console]
>>%temp%\consoleSIZEchanger.reg ECHO "WindowSize"=dword:%CMDpNewWindowSize%
>>%temp%\consoleSIZEchanger.reg ECHO "FontSize"=dword:%CMDpNewFont%
>>%temp%\consoleSIZEchanger.reg ECHO.
>>%temp%\consoleSIZEchanger.reg ECHO [HKEY_CURRENT_USER\Console\%%SystemRoot%%_system32_cmd.exe]
>>%temp%\consoleSIZEchanger.reg ECHO "WindowSize"=dword:%CMDpNewWindowSize%
>>%temp%\consoleSIZEchanger.reg ECHO "FontSize"=dword:%CMDpNewFont%
>>%temp%\consoleSIZEchanger.reg ECHO.
>>%temp%\consoleSIZEchanger.reg ECHO [HKEY_CURRENT_USER\Console\%%SystemRoot%%_system32_WindowsPowerShell_v1.0_powershell.exe]
>>%temp%\consoleSIZEchanger.reg ECHO "WindowSize"=dword:%CMDpNewWindowSize%
>>%temp%\consoleSIZEchanger.reg ECHO "FontSize"=dword:%CMDpNewFont%


::Merge and delete consoleSIZEchanger.reg
REGEDIT /S %temp%\consoleSIZEchanger.reg 
del %temp%\consoleSIZEchanger.reg 

::Copy Preconfigured Command Prompt/PowerShell shortcuts to Pinned Start Menu, Accessories and any other Custom Location you would define
copy "%homedrive%%homepath%\Documents\Command Prompt.%commandPromptLinkFlag%.lnk" "%homedrive%%homepath%\AppData\Roaming\Microsoft\Internet Explorer\Quick Launch\User Pinned\StartMenu\Command Prompt.lnk"
copy "%homedrive%%homepath%\Documents\Command Prompt.%commandPromptLinkFlag%.lnk" "%homedrive%%homepath%\AppData\Roaming\Microsoft\Windows\Start Menu\Programs\Accessories\Command Prompt.lnk"
copy "%homedrive%%homepath%\Documents\Windows PowerShell.%commandPromptLinkFlag%.lnk" "%homedrive%\ProgramData\Microsoft\Windows\Start Menu\Programs\Accessories\Windows PowerShell\Windows PowerShell.lnk"
copy "%homedrive%%homepath%\Documents\Windows PowerShell.%commandPromptLinkFlag%.lnk" "%homedrive%%homepath%\AppData\Roaming\Microsoft\Internet Explorer\Quick Launch\User Pinned\StartMenu\Windows PowerShell.lnk"                 
copy "%homedrive%%homepath%\Documents\Windows PowerShell (x86).%commandPromptLinkFlag%.lnk" "%homedrive%\ProgramData\Microsoft\Windows\Start Menu\Programs\Accessories\Windows PowerShell\Windows PowerShell (x86).lnk"
copy "%homedrive%%homepath%\Documents\Windows PowerShell (x86).%commandPromptLinkFlag%.lnk" "%homedrive%%homepath%\AppData\Roaming\Microsoft\Internet Explorer\Quick Launch\User Pinned\StartMenu\Windows PowerShell (x86).lnk"

console-720p.cmd:

::Assign New Window and Font Size for Windows Command Prompt
set CMDpNewFont=00100000
set CMDpNewWindowSize=0014007d
set commandPromptLinkFlag=720Res



 ::Make temporary .reg file to resize command console
>%temp%\consoleSIZEchanger.reg ECHO Windows Registry Editor Version 5.00
>>%temp%\consoleSIZEchanger.reg ECHO.
>>%temp%\consoleSIZEchanger.reg ECHO [HKEY_CURRENT_USER\Console]
>>%temp%\consoleSIZEchanger.reg ECHO "WindowSize"=dword:%CMDpNewWindowSize%
>>%temp%\consoleSIZEchanger.reg ECHO "FontSize"=dword:%CMDpNewFont%
>>%temp%\consoleSIZEchanger.reg ECHO.
>>%temp%\consoleSIZEchanger.reg ECHO [HKEY_CURRENT_USER\Console\%%SystemRoot%%_system32_cmd.exe]
>>%temp%\consoleSIZEchanger.reg ECHO "WindowSize"=dword:%CMDpNewWindowSize%
>>%temp%\consoleSIZEchanger.reg ECHO "FontSize"=dword:%CMDpNewFont%
>>%temp%\consoleSIZEchanger.reg ECHO.
>>%temp%\consoleSIZEchanger.reg ECHO [HKEY_CURRENT_USER\Console\%%SystemRoot%%_system32_WindowsPowerShell_v1.0_powershell.exe]
>>%temp%\consoleSIZEchanger.reg ECHO "WindowSize"=dword:%CMDpNewWindowSize%
>>%temp%\consoleSIZEchanger.reg ECHO "FontSize"=dword:%CMDpNewFont%


::Merge and delete consoleSIZEchanger.reg
REGEDIT /S %temp%\consoleSIZEchanger.reg 
del %temp%\consoleSIZEchanger.reg 

::Copy Preconfigured Command Prompt/PowerShell shortcuts to Pinned Start Menu, Accessories and any other Custom Location you would define
copy "%homedrive%%homepath%\Documents\Command Prompt.%commandPromptLinkFlag%.lnk" "%homedrive%%homepath%\AppData\Roaming\Microsoft\Internet Explorer\Quick Launch\User Pinned\StartMenu\Command Prompt.lnk"
copy "%homedrive%%homepath%\Documents\Command Prompt.%commandPromptLinkFlag%.lnk" "%homedrive%%homepath%\AppData\Roaming\Microsoft\Windows\Start Menu\Programs\Accessories\Command Prompt.lnk"
copy "%homedrive%%homepath%\Documents\Windows PowerShell.%commandPromptLinkFlag%.lnk" "%homedrive%\ProgramData\Microsoft\Windows\Start Menu\Programs\Accessories\Windows PowerShell\Windows PowerShell.lnk"
copy "%homedrive%%homepath%\Documents\Windows PowerShell.%commandPromptLinkFlag%.lnk" "%homedrive%%homepath%\AppData\Roaming\Microsoft\Internet Explorer\Quick Launch\User Pinned\StartMenu\Windows PowerShell.lnk"                 
copy "%homedrive%%homepath%\Documents\Windows PowerShell (x86).%commandPromptLinkFlag%.lnk" "%homedrive%\ProgramData\Microsoft\Windows\Start Menu\Programs\Accessories\Windows PowerShell\Windows PowerShell (x86).lnk"
copy "%homedrive%%homepath%\Documents\Windows PowerShell (x86).%commandPromptLinkFlag%.lnk" "%homedrive%%homepath%\AppData\Roaming\Microsoft\Internet Explorer\Quick Launch\User Pinned\StartMenu\Windows PowerShell (x86).lnk"

Returning pointer from a function

Although returning a pointer to a local object is bad practice, it didn't cause the kaboom here. Here's why you got a segfault:

int *fun()
{
    int *point;
    *point=12;  <<<<<<  your program crashed here.
    return point;
}

The local pointer goes out of scope, but the real issue is dereferencing a pointer that was never initialized. What is the value of point? Who knows. If the value did not map to a valid memory location, you will get a SEGFAULT. If by luck it mapped to something valid, then you just corrupted memory by overwriting that place with your assignment to 12.

Since the pointer returned was immediately used, in this case you could get away with returning a local pointer. However, it is bad practice because if that pointer was reused after another function call reused that memory in the stack, the behavior of the program would be undefined.

int *fun()
{
    int point;
    point = 12;
    return (&point);
}

or almost identically:

int *fun()
{
    int point;
    int *point_ptr;
    point_ptr = &point;
    *point_ptr = 12;
    return (point_ptr);
}

Another bad practice but safer method would be to declare the integer value as a static variable, and it would then not be on the stack and would be safe from being used by another function:

int *fun()
{
    static int point;
    int *point_ptr;
    point_ptr = &point;
    *point_ptr = 12;
    return (point_ptr);
}

or

int *fun()
{
    static int point;
    point = 12;
    return (&point);
}

As others have mentioned, the "right" way to do this would be to allocate memory on the heap, via malloc.

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

This is the most portable, least intrusive way:

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

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

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

Is right click a Javascript event?

This is worked with me

if (evt.xa.which == 3) 
{
    alert("Right mouse clicked");
}

Converting video to HTML5 ogg / ogv and mpg4

MS Expression Encoder can do mp4/h.264. not sure about ogg though.

Eclipse Generate Javadoc Wizard: what is "Javadoc Command"?

Yes, it is asking for the application/executable that is capable of creating Javadoc. There is a javadoc executable inside the jdk's bin folder.

Error ITMS-90717: "Invalid App Store Icon"

I also shell script using ffmpeg to resize images without alphachannel. It worked for png format fine.

# Export ios app icons by ffmpeg scale command
# usage: sh export_ios_icons.sh {path_to_your_img}
# example: sh export_ios_icons.sh ./app_icon.png

# sizes of images
# you can get other size images by editing thisarray
size=(20 40 60 29 58 87 80 120 180 76 152 167 1024)
for i in "${size[@]}"
do
   : 
    ffmpeg -i $1 -vf scale=$i:$i output_$ix$i.png
done

How to convert an object to JSON correctly in Angular 2 with TypeScript

If you are solely interested in outputting the JSON somewhere in your HTML, you could also use a pipe inside an interpolation. For example:

<p> {{ product | json }} </p>

I am not entirely sure it works for every AngularJS version, but it works perfectly in my Ionic App (which uses Angular 2+).

ASP.NET MVC 3 Razor: Include JavaScript file in the head tag

You can use Named Sections.

_Layout.cshtml

<head>
    <script type="text/javascript" src="@Url.Content("/Scripts/jquery-1.6.2.min.js")"></script>
    @RenderSection("JavaScript", required: false)
</head>

_SomeView.cshtml

@section JavaScript
{
   <script type="text/javascript" src="@Url.Content("/Scripts/SomeScript.js")"></script>
   <script type="text/javascript" src="@Url.Content("/Scripts/AnotherScript.js")"></script>
}

Default text which won't be shown in drop-down list

Kyle's solution worked perfectly fine for me so I made my research in order to avoid any Js and CSS, but just sticking with HTML. Adding a value of selected to the item we want to appear as a header forces it to show in the first place as a placeholder. Something like:

<option selected disabled>Choose here</option>

The complete markup should be along these lines:

<select>
    <option selected disabled>Choose here</option>
    <option value="1">One</option>
    <option value="2">Two</option>
    <option value="3">Three</option>
    <option value="4">Four</option>
    <option value="5">Five</option>
</select>

You can take a look at this fiddle, and here's the result:

enter image description here

If you do not want the sort of placeholder text to appear listed in the options once a user clicks on the select box just add the hidden attribute like so:

<select>
    <option selected disabled hidden>Choose here</option>
    <option value="1">One</option>
    <option value="2">Two</option>
    <option value="3">Three</option>
    <option value="4">Four</option>
    <option value="5">Five</option>
</select>

Check the fiddle here and the screenshot below.

enter image description here


Here is the solution:

<select>
    <option style="display:none;" selected>Select language</option>
    <option>Option 1</option>
    <option>Option 2</option>
</select>

Algorithm/Data Structure Design Interview Questions

  1. Write a method that takes a string, and returns true if that string is a number.(anything with regex as the most effective answer for an interview)
  2. Please write an abstract factory method, that doesn't contain a switch and returns types with the base type of "X". (Looking for patterns, looking for reflection, looking for them to not side step and use an if else if)
  3. Please split the string "every;thing|;|else|;|in|;|he;re" by the token "|;|".(multi character tokens are not allowed at least in .net, so looking for creativity, the best solution is a total hack)

How to test which port MySQL is running on and whether it can be connected to?

If you are on a system where netstat is not available (e.g. RHEL 7 and more recent Debian releases) you can use ss, as below:

sudo ss -tlpn | grep mysql

And you'll get something like the following for output:

LISTEN     0      50        *:3306        *:*        users:(("mysqld",pid=5307,fd=14))

The fourth column is Local Address:Port. So in this case Mysql is listening on port 3306, the default.

How to select data from 30 days?

Short version for easy use:

SELECT * 
FROM [TableName] t
WHERE t.[DateColumnName] >= DATEADD(month, -1, GETDATE())

DATEADD and GETDATE are available in SQL Server starting with 2008 version. MSDN documentation: GETDATE and DATEADD.

Simplest way to detect keypresses in javascript

With plain Javascript, the simplest is:

document.onkeypress = function (e) {
    e = e || window.event;
    // use e.keyCode
};

But with this, you can only bind one handler for the event.

In addition, you could use the following to be able to potentially bind multiple handlers to the same event:

addEvent(document, "keypress", function (e) {
    e = e || window.event;
    // use e.keyCode
});

function addEvent(element, eventName, callback) {
    if (element.addEventListener) {
        element.addEventListener(eventName, callback, false);
    } else if (element.attachEvent) {
        element.attachEvent("on" + eventName, callback);
    } else {
        element["on" + eventName] = callback;
    }
}

In either case, keyCode isn't consistent across browsers, so there's more to check for and figure out. Notice the e = e || window.event - that's a normal problem with Internet Explorer, putting the event in window.event instead of passing it to the callback.

References:

With jQuery:

$(document).on("keypress", function (e) {
    // use e.which
});

Reference:

Other than jQuery being a "large" library, jQuery really helps with inconsistencies between browsers, especially with window events...and that can't be denied. Hopefully it's obvious that the jQuery code I provided for your example is much more elegant and shorter, yet accomplishes what you want in a consistent way. You should be able to trust that e (the event) and e.which (the key code, for knowing which key was pressed) are accurate. In plain Javascript, it's a little harder to know unless you do everything that the jQuery library internally does.

Note there is a keydown event, that is different than keypress. You can learn more about them here: onKeyPress Vs. onKeyUp and onKeyDown

As for suggesting what to use, I would definitely suggest using jQuery if you're up for learning the framework. At the same time, I would say that you should learn Javascript's syntax, methods, features, and how to interact with the DOM. Once you understand how it works and what's happening, you should be more comfortable working with jQuery. To me, jQuery makes things more consistent and is more concise. In the end, it's Javascript, and wraps the language.

Another example of jQuery being very useful is with AJAX. Browsers are inconsistent with how AJAX requests are handled, so jQuery abstracts that so you don't have to worry.

Here's something that might help decide:

Pytorch tensor to numpy array

This worked for me:

np_arr = torch_tensor.cpu().detach().numpy()

How can I import a database with MySQL from terminal?

Open Terminal Then

 mysql -u root -p

 eg:- mysql -u shabeer -p

After That Create a Database

 mysql> create database "Name";

 eg:- create database INVESTOR;

Then Select That New Database "INVESTOR"

 mysql> USE INVESTOR;

Select the path of sql file from machine

 mysql> source /home/shabeer/Desktop/new_file.sql;

Then press enter and wait for some times if it's all executed then

 mysql> exit

enter image description here

ios Upload Image and Text using HTTP POST

Upload image with form data using NSURLConnection class in Swift 2.2:

    func uploadImage(){
        let imageData = UIImagePNGRepresentation(UIImage(named: "dexter.jpg")!)

        if imageData != nil{
            let str = "https://staging.mywebsite.com/V2.9/uploadfile"
            let request = NSMutableURLRequest(URL: NSURL(string:str)!)
            request.HTTPMethod = "POST"

            let boundary = NSString(format: "---------------------------14737809831466499882746641449")

            let contentType = NSString(format: "multipart/form-data; boundary=%@",boundary)
            request.addValue(contentType as String, forHTTPHeaderField: "Content-Type")

            let body = NSMutableData()

            // append image data to body
            body.appendData(NSString(format: "\r\n--%@\r\n", boundary).dataUsingEncoding(NSUTF8StringEncoding)!)
            body.appendData(NSString(format:"Content-Disposition: form-data; name=\"file\"; filename=\"img.jpg\"\\r\n").dataUsingEncoding(NSUTF8StringEncoding)!)
            body.appendData(NSString(format: "Content-Type: application/octet-stream\r\n\r\n").dataUsingEncoding(NSUTF8StringEncoding)!)
            body.appendData(imageData!)
            body.appendData(NSString(format: "\r\n--%@\r\n", boundary).dataUsingEncoding(NSUTF8StringEncoding)!)

            request.HTTPBody = body

            do {
                let returnData = try NSURLConnection.sendSynchronousRequest(request, returningResponse: nil)
                let returnString = NSString(data: returnData, encoding: NSUTF8StringEncoding)
                print("returnString = \(returnString!)")
            }
            catch let  error as NSError {
                print(error.description)
            }
        }
    }

Note: Always use sendAsynchronousRequest method instead of sendSynchronousRequest for uploading/downloading data to avoid blocking main thread. Here I used sendSynchronousRequest for testing purpose only.

How to make padding:auto work in CSS?

if you're goal is to reset EVERYTHING then @Björn's answer should be your goal but applied as:

* {
  padding: initial;
}

if this is loaded after your original reset.css should have the same weight and will rely on each browser's default padding as initial value.

Remove duplicates from dataframe, based on two columns A,B, keeping row with max value in another column C

You can do it with drop_duplicates as you wanted

# initialisation
d = pd.DataFrame({'A' : [1,1,2,3,3], 'B' : [2,2,7,4,4],  'C' : [1,4,1,0,8]})

d = d.sort_values("C", ascending=False)
d = d.drop_duplicates(["A","B"])

If it's important to get the same order

d = d.sort_index()

Which regular expression operator means 'Don't' match this character?

You can use negated character classes to exclude certain characters: for example [^abcde] will match anything but a,b,c,d,e characters.

Instead of specifying all the characters literally, you can use shorthands inside character classes: [\w] (lowercase) will match any "word character" (letter, numbers and underscore), [\W] (uppercase) will match anything but word characters; similarly, [\d] will match the 0-9 digits while [\D] matches anything but the 0-9 digits, and so on.

If you use PHP you can take a look at the regex character classes documentation.

Commenting multiple lines in DOS batch file

You can use a goto to skip over code.

goto comment
...skip this...
:comment

How to have image and text side by side

HTML

<div class='containerBox'>
    <div>
       <img src='http://ecx.images-amazon.com/images/I/21-leKb-zsL._SL500_AA300_.png' class='iconDetails'>
       <div>
       <h4>Facebook</h4>  
       <div style="font-size:.6em;float:left; margin-left:5px;color:white;">fine location, GPS, coarse location</div>
       <div style="float:right;font-size:.6em; margin-right:5px; color:white;">0 mins ago</div>
       </div>
   </div> 
</div>

CSS

 .iconDetails {
 margin-left:2%;
 float:left; 
 height:40px;
 width:40px;
 } 

.containerBox {
width:300px;
height:60px;
padding:1px;
background-color:#303030;
}
h4{
margin:0px;
margin-top:3%;
margin-left:50px;
color:white;
}

How can I wrap text in a label using WPF?

I used this to retrieve data from MySql Database:

AccessText a = new AccessText();    
a.Text=reader[1].ToString();       // MySql reader
a.Width = 70;
a.TextWrapping = TextWrapping.WrapWithOverflow;
labels[i].Content = a;

How to set some xlim and ylim in Seaborn lmplot facetgrid

You need to get hold of the axes themselves. Probably the cleanest way is to change your last row:

lm = sns.lmplot('X','Y',df,col='Z',sharex=False,sharey=False)

Then you can get hold of the axes objects (an array of axes):

axes = lm.axes

After that you can tweak the axes properties

axes[0,0].set_ylim(0,)
axes[0,1].set_ylim(0,)

creates:

enter image description here

sqlplus statement from command line

I assume this is *nix?

Use "here document":

sqlplus -s user/pass <<+EOF
select 1 from dual;
+EOF

EDIT: I should have tried your second example. It works, too (even in Windows, sans ticks):

$ echo 'select 1 from dual;'|sqlplus -s user/pw

         1
----------
         1


$

How to change cursor from pointer to finger using jQuery?

$('selector').css('cursor', 'pointer'); // 'default' to revert

I know that may be confusing per your original question, but the "finger" cursor is actually called "pointer".

The normal arrow cursor is just "default".

all possible default pointer looks DEMO

Twitter bootstrap hide element on small devices

Bootstrap 4

The display (hidden/visible) classes are changed in Bootstrap 4. To hide on the xs viewport use:

d-none d-sm-block

Also see: Missing visible-** and hidden-** in Bootstrap v4


Bootstrap 3 (original answer)

Use the hidden-xs utility class..

<nav class="col-sm-3 hidden-xs">
        <ul class="list-unstyled">
        <li>Text 10</li>
        <li>Text 11</li>
        <li>Text 12</li>
        </ul>
</nav>

http://bootply.com/90722

Understanding __getitem__ method

The magic method __getitem__ is basically used for accessing list items, dictionary entries, array elements etc. It is very useful for a quick lookup of instance attributes.

Here I am showing this with an example class Person that can be instantiated by 'name', 'age', and 'dob' (date of birth). The __getitem__ method is written in a way that one can access the indexed instance attributes, such as first or last name, day, month or year of the dob, etc.

import copy

# Constants that can be used to index date of birth's Date-Month-Year
D = 0; M = 1; Y = -1

class Person(object):
    def __init__(self, name, age, dob):
        self.name = name
        self.age = age
        self.dob = dob

    def __getitem__(self, indx):
        print ("Calling __getitem__")
        p = copy.copy(self)

        p.name = p.name.split(" ")[indx]
        p.dob = p.dob[indx] # or, p.dob = p.dob.__getitem__(indx)
        return p

Suppose one user input is as follows:

p = Person(name = 'Jonab Gutu', age = 20, dob=(1, 1, 1999))

With the help of __getitem__ method, the user can access the indexed attributes. e.g.,

print p[0].name # print first (or last) name
print p[Y].dob  # print (Date or Month or ) Year of the 'date of birth'

Seeking useful Eclipse Java code templates

I like a generated class comment like this:

/**
 * I... 
 * 
 * $Id$
 */

The "I..." immediately encourages the developer to describe what the class does. I does seem to improve the problem of undocumented classes.

And of course the $Id$ is a useful CVS keyword.

Getting Current time to display in Label. VB.net

Try This.....

Private Sub Form1_Load(ByVal sender As System.Object, ByVal e As System.EventArgs) Handles MyBase.Load    
    Timer1.Start()
End Sub

Private Sub Timer1_Tick(ByVal sender As System.Object, ByVal e As System.EventArgs) Handles Timer1.Tick
    Label12.Text = TimeOfDay.ToString("h:mm:ss tt")
End Sub

How do I change button size in Python?

Configuring a button (or any widget) in Tkinter is done by calling a configure method "config"

To change the size of a button called button1 you simple call

button1.config( height = WHATEVER, width = WHATEVER2 )

If you know what size you want at initialization these options can be added to the constructor.

button1 = Button(self, text = "Send", command = self.response1, height = 100, width = 100) 

How to unmount a busy device

If possible, let us locate/identify the busy process, kill that process and then unmount the samba share/ drive to minimize damage:

  • lsof | grep '<mountpoint of /dev/sda1>' (or whatever the mounted device is)

  • pkill target_process (kills busy proc. by name | kill PID | killall target_process)

  • umount /dev/sda1 (or whatever the mounted device is)

Android SQLite: Update Statement

I use this class to handle database.I hope it will help some one in future.

Happy coding.

public class Database {

private static class DBHelper extends SQLiteOpenHelper {

    /**
     * Database name
     */
    private static final String DB_NAME = "db_name";

    /**
     * Table Names
     */
    public static final String TABLE_CART = "DB_CART";


    /**
     *  Cart Table Columns
     */
    public static final String CART_ID_PK = "_id";// Primary key

    public static final String CART_DISH_NAME = "dish_name";
    public static final String CART_DISH_ID = "menu_item_id";
    public static final String CART_DISH_QTY = "dish_qty";
    public static final String CART_DISH_PRICE = "dish_price";

    /**
     * String to create reservation tabs table
     */
    private final String CREATE_TABLE_CART = "CREATE TABLE IF NOT EXISTS "
            + TABLE_CART + " ( "
            + CART_ID_PK + " INTEGER PRIMARY KEY, "
            + CART_DISH_NAME + " TEXT , "
            + CART_DISH_ID + " TEXT , "
            + CART_DISH_QTY + " TEXT , "
            + CART_DISH_PRICE + " TEXT);";


    public DBHelper(Context context) {
        super(context, DB_NAME, null, 2);

    }

    @Override
    public void onCreate(SQLiteDatabase db) {
        db.execSQL(CREATE_TABLE_CART);


    }

    @Override
    public void onUpgrade(SQLiteDatabase db, int arg1, int arg2) {
        db.execSQL("DROP TABLE IF EXISTS " + CREATE_TABLE_CART);
        onCreate(db);
    }

}


     /**
      * CART handler
      */
      public static class Cart {


    /**
     * Check if Cart is available or not
     *
     * @param context
     * @return
     */
    public static boolean isCartAvailable(Context context) {

        DBHelper dbHelper = new DBHelper(context);
        SQLiteDatabase db = dbHelper.getReadableDatabase();
        boolean exists = false;

        try {
            String query = "SELECT * FROM " + DBHelper.TABLE_CART;
            Cursor cursor = db.rawQuery(query, null);
            exists = (cursor.getCount() > 0);
            cursor.close();
            db.close();
        } catch (SQLiteException e) {
            db.close();
        }

        return exists;
    }


    /**
     * Insert values in cart table
     *
     * @param context
     * @param dishName
     * @param dishPrice
     * @param dishQty
     * @return
     */
    public static boolean insertItem(Context context, String itemId, String dishName, String dishPrice, String dishQty) {

        DBHelper dbHelper = new DBHelper(context);
        SQLiteDatabase db = dbHelper.getWritableDatabase();
        ContentValues values = new ContentValues();
        values.put(DBHelper.CART_DISH_ID, "" + itemId);
        values.put(DBHelper.CART_DISH_NAME, "" + dishName);
        values.put(DBHelper.CART_DISH_PRICE, "" + dishPrice);
        values.put(DBHelper.CART_DISH_QTY, "" + dishQty);

        try {
            db.insert(DBHelper.TABLE_CART, null, values);
            db.close();
            return true;
        } catch (SQLiteException e) {
            db.close();
            return false;
        }
    }

    /**
     * Check for specific record by name
     *
     * @param context
     * @param dishName
     * @return
     */
    public static boolean isItemAvailable(Context context, String dishName) {

        DBHelper dbHelper = new DBHelper(context);
        SQLiteDatabase db = dbHelper.getReadableDatabase();
        boolean exists = false;

        String query = "SELECT * FROM " + DBHelper.TABLE_CART + " WHERE "
                + DBHelper.CART_DISH_NAME + " = '" + String.valueOf(dishName) + "'";


        try {
            Cursor cursor = db.rawQuery(query, null);

            exists = (cursor.getCount() > 0);
            cursor.close();

        } catch (SQLiteException e) {

            e.printStackTrace();
            db.close();

        }

        return exists;
    }

    /**
     * Update cart item by item name
     *
     * @param context
     * @param dishName
     * @param dishPrice
     * @param dishQty
     * @return
     */
    public static boolean updateItem(Context context, String itemId, String dishName, String dishPrice, String dishQty) {

        DBHelper dbHelper = new DBHelper(context);
        SQLiteDatabase db = dbHelper.getWritableDatabase();
        ContentValues values = new ContentValues();
        values.put(DBHelper.CART_DISH_ID, itemId);
        values.put(DBHelper.CART_DISH_NAME, dishName);
        values.put(DBHelper.CART_DISH_PRICE, dishPrice);
        values.put(DBHelper.CART_DISH_QTY, dishQty);

        try {

            String[] args = new String[]{dishName};
            db.update(DBHelper.TABLE_CART, values, DBHelper.CART_DISH_NAME + "=?", args);

            db.close();


            return true;
        } catch (SQLiteException e) {
            db.close();

            return false;
        }
    }

    /**
     * Get cart list
     *
     * @param context
     * @return
     */
    public static ArrayList<CartModel> getCartList(Context context) {

        DBHelper dbHelper = new DBHelper(context);
        SQLiteDatabase db = dbHelper.getReadableDatabase();

        ArrayList<CartModel> cartList = new ArrayList<>();

        try {
            String query = "SELECT * FROM " + DBHelper.TABLE_CART + ";";

            Cursor cursor = db.rawQuery(query, null);


            for (cursor.moveToFirst(); !cursor.isAfterLast(); cursor.moveToNext()) {

                cartList.add(new CartModel(
                        cursor.getString(cursor.getColumnIndex(DBHelper.CART_DISH_ID)),
                        cursor.getString(cursor.getColumnIndex(DBHelper.CART_DISH_NAME)),
                        cursor.getString(cursor.getColumnIndex(DBHelper.CART_DISH_QTY)),
                        Integer.parseInt(cursor.getString(cursor.getColumnIndex(DBHelper.CART_DISH_PRICE)))
                ));
            }

            db.close();

        } catch (SQLiteException e) {
            db.close();
        }
        return cartList;
    }

   /**
     * Get total amount of cart items
     *
     * @param context
     * @return
     */
    public static String getTotalAmount(Context context) {

        DBHelper dbHelper = new DBHelper(context);
        SQLiteDatabase db = dbHelper.getReadableDatabase();

        double totalAmount = 0.0;

        try {
            String query = "SELECT * FROM " + DBHelper.TABLE_CART + ";";

            Cursor cursor = db.rawQuery(query, null);


            for (cursor.moveToFirst(); !cursor.isAfterLast(); cursor.moveToNext()) {

                totalAmount = totalAmount + Double.parseDouble(cursor.getString(cursor.getColumnIndex(DBHelper.CART_DISH_PRICE))) *
                        Double.parseDouble(cursor.getString(cursor.getColumnIndex(DBHelper.CART_DISH_QTY)));
            }

            db.close();


        } catch (SQLiteException e) {
            db.close();
        }


        if (totalAmount == 0.0)
            return "";
        else
            return "" + totalAmount;
    }


    /**
     * Get item quantity
     *
     * @param context
     * @param dishName
     * @return
     */
    public static String getItemQty(Context context, String dishName) {

        DBHelper dbHelper = new DBHelper(context);
        SQLiteDatabase db = dbHelper.getReadableDatabase();

        Cursor cursor = null;
        String query = "SELECT * FROM " + DBHelper.TABLE_CART + " WHERE " + DBHelper.CART_DISH_NAME + " = '" + dishName + "';";
        String quantity = "0";

        try {
            cursor = db.rawQuery(query, null);

            if (cursor.getCount() > 0) {

                cursor.moveToFirst();
                quantity = cursor.getString(cursor
                        .getColumnIndex(DBHelper.CART_DISH_QTY));

                return quantity;
            }


        } catch (SQLiteException e) {
            e.printStackTrace();
        }

        return quantity;
    }


    /**
     * Delete cart item by name
     *
     * @param context
     * @param dishName
     */
    public static void deleteCartItem(Context context, String dishName) {
        DBHelper dbHelper = new DBHelper(context);
        SQLiteDatabase db = dbHelper.getReadableDatabase();

        try {

            String[] args = new String[]{dishName};
            db.delete(DBHelper.TABLE_CART, DBHelper.CART_DISH_NAME + "=?", args);

            db.close();
        } catch (SQLiteException e) {
            db.close();
            e.printStackTrace();
        }

    }


}//End of cart class

/**
 * Delete database table
 *
 * @param context
 */
public static void deleteCart(Context context) {
    DBHelper dbHelper = new DBHelper(context);
    SQLiteDatabase db = dbHelper.getReadableDatabase();

    try {

        db.execSQL("DELETE FROM " + DBHelper.TABLE_CART);

    } catch (SQLiteException e) {
        e.printStackTrace();
    }

}

}

Usage:

  if(Database.Cart.isCartAvailable(context)){

       Database.deleteCart(context);

   }

Java: Add elements to arraylist with FOR loop where element name has increasing number

Put the answers into an array and iterate over it:

List<Answer> answers = new ArrayList<Answer>(3);

for (Answer answer : new Answer[] {answer1, answer2, answer3}) {
    list.add(answer);
}

EDIT

See João's answer for a much better solution. I'm still leaving my answer here as another option.

How to simplify a null-safe compareTo() implementation?

You can extract method:

public int cmp(String txt, String otherTxt)
{
    if ( txt == null )
        return otjerTxt == null ? 0 : 1;

    if ( otherTxt == null )
          return 1;

    return txt.compareToIgnoreCase(otherTxt);
}

public int compareTo(Metadata other) {
   int result = cmp( name, other.name); 
   if ( result != 0 )  return result;
   return cmp( value, other.value); 

}

Position Relative vs Absolute?

Relative : Relative to it’s current position, but can be moved. Or A RELATIVE positioned element is positioned relative to ITSELF.

Absolute : An ABSOLUTE positioned element is positioned relative to IT'S CLOSEST POSITIONED PARENT. if one is present, then it works like fixed.....relative to the window.

<div style="position:relative"> <!--2nd parent div-->
    <div>   <!--1st parent div-->
        <div style="position:absolute;left:10px;....."> <!--Middle div-->
          Md. Arif
       </div>
    </div>
</div>

Here, 2nd parent div position is relative so the middle div will changes it's position with respect to 2nd parent div. If 1st parent div position would relative then the Middle div would changes it's position with respect to 1st parent div. Details

Bootstrap - 5 column layout

_x000D_
_x000D_
.col-xs-2{_x000D_
    background:#00f;_x000D_
    color:#FFF;_x000D_
}_x000D_
.col-half-offset{_x000D_
    margin-left:4.166666667%_x000D_
}
_x000D_
<link href="https://maxcdn.bootstrapcdn.com/bootstrap/3.3.5/css/bootstrap.min.css" rel="stylesheet"/>_x000D_
<div class="container">_x000D_
    <div class="row" style="border: 1px solid red">_x000D_
        <div class="col-xs-2" id="p1">One</div>_x000D_
        <div class="col-xs-2 col-half-offset" id="p2">Two</div>_x000D_
        <div class="col-xs-2 col-half-offset" id="p3">Three</div>_x000D_
        <div class="col-xs-2 col-half-offset" id="p4">Four</div>_x000D_
        <div class="col-xs-2 col-half-offset" id="p5">Five</div>_x000D_
        <div>lorem</div>_x000D_
    </div>_x000D_
</div>
_x000D_
_x000D_
_x000D_

This should be ok.

Remove a child with a specific attribute, in SimpleXML for PHP

This work for me:

$data = '<data>
<seg id="A1"/>
<seg id="A5"/>
<seg id="A12"/>
<seg id="A29"/>
<seg id="A30"/></data>';

$doc = new SimpleXMLElement($data);

$segarr = $doc->seg;

$count = count($segarr);

$j = 0;

for ($i = 0; $i < $count; $i++) {

    if ($segarr[$j]['id'] == 'A12') {
        unset($segarr[$j]);
        $j = $j - 1;
    }
    $j = $j + 1;
}

echo $doc->asXml();

How to add an extra column to a NumPy array

I think:

np.column_stack((a, zeros(shape(a)[0])))

is more elegant.

What is the difference between "screen" and "only screen" in media queries?

@media screen and (max-width:480px) { … } 

screen here is to set the screen size of the media query. E.g the maximum width of the display area is 480px. So it is specifying the screen as opposed to the other available media types.

@media only screen and (max-width: 480px;) { … } 

only screen here is used to prevent older browsers that do not support media queries with media features from applying the specified styles.

How to use JavaScript source maps (.map files)?

Just wanted to focus on the last part of the question; How source map files are created? by listing the build tools I know that can create source maps.

  1. Grunt: using plugin grunt-contrib-uglify
  2. Gulp: using plugin gulp-uglify
  3. Google closure: using parameter --create_source_map

Change arrow colors in Bootstraps carousel

You should use also: <span><i class="fa fa-angle-left" aria-hidden="true"></i></span> using fontawesome. You have to overwrite the original code. Do the following and you'll be free to customize on CSS:

<a class="carousel-control-prev" href="#carouselExampleIndicatorsTestim" role="button" data-slide="prev">
    <span><i class="fa fa-angle-left" aria-hidden="true"></i></span>
    <span class="sr-only">Previous</span>
</a>
<a class="carousel-control-next" href="#carouselExampleIndicatorsTestim" role="button" data-slide="next">
    <span><i class="fa fa-angle-right" aria-hidden="true"></i></span>
    <span class="sr-only">Next</span>
 </a>

The original code

<a class="carousel-control-prev" href="#carouselExampleIndicators" role="button" data-slide="prev">
    <span class="carousel-control-prev-icon" aria-hidden="true"></span>
    <span class="sr-only">Previous</span>
</a>

<a class="carousel-control-next" href="#carouselExampleIndicators" role="button" data-slide="next">
    <span class="carousel-control-next-icon" aria-hidden="true"></span>
    <span class="sr-only">Next</span>
</a>

Handling multiple IDs in jQuery

Yes, #id selectors combined with a multiple selector (comma) is perfectly valid in both jQuery and CSS.

However, for your example, since <script> comes before the elements, you need a document.ready handler, so it waits until the elements are in the DOM to go looking for them, like this:

<script>
  $(function() {
    $("#segement1,#segement2,#segement3").hide()
  });
</script>

<div id="segement1"></div>
<div id="segement2"></div>
<div id="segement3"></div>

How do I start my app on startup?

Listen for the ACTION_BOOT_COMPLETE and do what you need to from there. There is a code snippet here.

Update:

Original link on answer is down, so based on the comments, here it is linked code, because no one would ever miss the code when the links are down.

In AndroidManifest.xml (application-part):

<receiver android:enabled="true" android:name=".BootUpReceiver"
        android:permission="android.permission.RECEIVE_BOOT_COMPLETED">

        <intent-filter>
                <action android:name="android.intent.action.BOOT_COMPLETED" />
                <category android:name="android.intent.category.DEFAULT" />
        </intent-filter>
</receiver>

...

<uses-permission android:name="android.permission.RECEIVE_BOOT_COMPLETED" />

...

public class BootUpReceiver extends BroadcastReceiver{

        @Override
        public void onReceive(Context context, Intent intent) {
                Intent i = new Intent(context, MyActivity.class);  //MyActivity can be anything which you want to start on bootup...
                i.addFlags(Intent.FLAG_ACTIVITY_NEW_TASK);
                context.startActivity(i);  
        }

}

Source: https://web.archive.org/web/20150520124552/http://www.androidsnippets.com/autostart-an-application-at-bootup

What causes imported Maven project in Eclipse to use Java 1.5 instead of Java 1.6 by default and how can I ensure it doesn't?

Project specific settings

One more place where this can go wrong is in the project specific settings, in Eclipse.

  1. project properties: click your project and one of the following:

    • Alt + Enter
    • Menu > Project > Properties
    • right click your project > project properties (last item in the menu)
  2. click on "Java Compiler"

  3. Uncheck "Enable project specific settings" (or change them all by hand).

Because of client requirements we had them enabled to keep our projects in 1.6. When it was needed to upgrade to 1.7, we had a hard time because we needed to change the java version all over the place:

  • project POM
  • Eclipse Workspace default
  • project specific settings
  • executing virtual machine (1.6 was used for everything)

Best tool for inspecting PDF files?

If you want to work programmatically from within Python, pdfminer is a good option. It allows you to work with PDF structure in memory as an object hierarchy or serialize it as XML.

Getting the parameters of a running JVM

I am adding this new answer because as per JDK8 documentation jcmd is suggested approach now.

It is suggested to use the latest utility, jcmd instead of the previous jstack, jinfo, and jmap utilities for enhanced diagnostics and reduced performance overhead.

Below are commands to get your properties/flags you want.

jcmd pid VM.system_properties
jcmd pid VM.flags

We need pid, for this use jcmd -l, like below

username@users-Air:~/javacode$ jcmd -l 
11441 Test 
6294 Test 
29197 jdk.jcmd/sun.tools.jcmd.JCmd -l 

Now time to use these pids to get properties/flags you want

Command: jcmd 11441 VM.system_properties

11441:
#Tue Oct 17 12:44:50 IST 2017
gopherProxySet=false
awt.toolkit=sun.lwawt.macosx.LWCToolkit
file.encoding.pkg=sun.io
java.specification.version=9
sun.cpu.isalist=
sun.jnu.encoding=UTF-8
java.class.path=.
java.vm.vendor=Oracle Corporation
sun.arch.data.model=64
java.vendor.url=http\://java.oracle.com/
user.timezone=Asia/Kolkata
java.vm.specification.version=9
os.name=Mac OS X
sun.java.launcher=SUN_STANDARD
user.country=US
sun.boot.library.path=/Library/Java/JavaVirtualMachines/jdk-9.jdk/Contents/Home/lib
sun.java.command=Test
http.nonProxyHosts=local|*.local|169.254/16|*.169.254/16
jdk.debug=release
sun.cpu.endian=little
user.home=/Users/XXXX
user.language=en
java.specification.vendor=Oracle Corporation
java.home=/Library/Java/JavaVirtualMachines/jdk-9.jdk/Contents/Home
file.separator=/
java.vm.compressedOopsMode=Zero based
line.separator=\n
java.specification.name=Java Platform API Specification
java.vm.specification.vendor=Oracle Corporation
java.awt.graphicsenv=sun.awt.CGraphicsEnvironment
sun.management.compiler=HotSpot 64-Bit Tiered Compilers
ftp.nonProxyHosts=local|*.local|169.254/16|*.169.254/16
java.runtime.version=9+181
user.name=XXXX
path.separator=\:
os.version=10.12.6
java.runtime.name=Java(TM) SE Runtime Environment
file.encoding=UTF-8
java.vm.name=Java HotSpot(TM) 64-Bit Server VM
java.vendor.url.bug=http\://bugreport.java.com/bugreport/
java.io.tmpdir=/var/folders/dm/gd6lc90d0hg220lzw_m7krr00000gn/T/
java.version=9
user.dir=/Users/XXXX/javacode
os.arch=x86_64
java.vm.specification.name=Java Virtual Machine Specification
java.awt.printerjob=sun.lwawt.macosx.CPrinterJob
sun.os.patch.level=unknown
MyParam=2
java.library.path=/Users/XXXX/Library/Java/Extensions\:/Library/Java/Extensions\:/Network/Library/Java/Extensions\:/System/Library/Java/Extensions\:/usr/lib/java\:.
java.vm.info=mixed mode
java.vendor=Oracle Corporation
java.vm.version=9+181
sun.io.unicode.encoding=UnicodeBig
java.class.version=53.0
socksNonProxyHosts=local|*.local|169.254/16|*.169.254/16

Command : jcmd 11441 VM.flags output:

11441:
-XX:CICompilerCount=3 -XX:ConcGCThreads=1 -XX:G1ConcRefinementThreads=4 -XX:G1HeapRegionSize=1048576 -XX:InitialHeapSize=67108864 -XX:MarkStackSize=4194304 -XX:MaxHeapSize=1073741824 -XX:MaxNewSize=643825664 -XX:MinHeapDeltaBytes=1048576 -XX:NonNMethodCodeHeapSize=5830092 -XX:NonProfiledCodeHeapSize=122914074 -XX:ProfiledCodeHeapSize=122914074 -XX:ReservedCodeCacheSize=251658240 -XX:+SegmentedCodeCache -XX:-UseAOT -XX:+UseCompressedClassPointers -XX:+UseCompressedOops -XX:+UseFastUnorderedTimeStamps -XX:+UseG1GC 

For more instructions of usages of jcmd, see my blog post

Get a list of numbers as input from the user

try this one ,

n=int(raw_input("Enter length of the list"))
l1=[]
for i in range(n):
    a=raw_input()
    if(a.isdigit()):
        l1.insert(i,float(a)) #statement1
    else:
        l1.insert(i,a)        #statement2

If the element of the list is just a number the statement 1 will get executed and if it is a string then statement 2 will be executed. In the end you will have an list l1 as you needed.

Git Clone - Repository not found

If you are using cygwin for git and trying to clone a git repository from a network drive you need to add the cygdrive path.

For example if you are cloning a git repo from z:/

$ git clone /cygdrive/z/[repo].git

How to git-cherry-pick only changes to certain files?

You can use:

git diff <commit>^ <commit> -- <path> | git apply

The notation <commit>^ specifies the (first) parent of <commit>. Hence, this diff command picks the changes made to <path> in the commit <commit>.

Note that this won't commit anything yet (as git cherry-pick does). So if you want that, you'll have to do:

git add <path>
git commit

Hide/encrypt password in bash file to stop accidentally seeing it

I used base64 for the overcoming the same problem, i.e. people can see my password over my shoulder.

Here is what I did - I created a new "db_auth.cfg" file and created parameters with one being my db password. I set the permission as 750 for the file.

DB_PASSWORD=Z29vZ2xl

In my shell script I used the "source" command to get the file and then decode it back to use in my script.

source path_to_the_file/db_auth.cfg
DB_PASSWORD=$(eval echo ${DB_PASSWORD} | base64 --decode)

I hope this helps.

NodeJS accessing file with relative path

You can use the path module to join the path of the directory in which helper1.js lives to the relative path of foobar.json. This will give you the absolute path to foobar.json.

var fs = require('fs');
var path = require('path');

var jsonPath = path.join(__dirname, '..', 'config', 'dev', 'foobar.json');
var jsonString = fs.readFileSync(jsonPath, 'utf8');

This should work on Linux, OSX, and Windows assuming a UTF8 encoding.

How can I send emails through SSL SMTP with the .NET Framework?

I know I'm joining late to the discussion, but I think this can be useful to others.

I wanted to avoid deprecated stuff and after a lot of fiddling I found a simple way to send to servers requiring Implicit SSL: use NuGet and add the MailKit package to the project. (I used VS2017 targetting .NET 4.6.2 but it should work on lower .NET versions...)

Then you'll only need to do something like this:

using MailKit.Net.Smtp;
using MimeKit;

var client = new SmtpClient();
client.Connect("server.name", 465, true);

// Note: since we don't have an OAuth2 token, disable the XOAUTH2 authentication mechanism.
client.AuthenticationMechanisms.Remove ("XOAUTH2");

if (needsUserAndPwd)
{
    // Note: only needed if the SMTP server requires authentication
    client.Authenticate (user, pwd);
}

var msg = new MimeMessage();
msg.From.Add(new MailboxAddress("[email protected]"));
msg.To  .Add(new MailboxAddress("[email protected]"));
msg.Subject = "This is a test subject";

msg.Body = new TextPart("plain") {
    Text = "This is a sample message body"
};

client.Send(msg);
client.Disconnect(true);

Of course you can also tweak it to use Explicit SSL or no transport security at all.

Multiple distinct pages in one HTML file

Solution 1

One solution for this, not requiring any JavaScript, is simply to create a single page in which the multiple pages are simply regular content that is separated by a lot of white space. They can be wrapped into div containers, and an inline style sheet can endow them with the margin:

<style>
.subpage { margin-bottom: 2048px; }
</style>
... main page ...

<div class="subpage">
<!-- first one is empty on purpose: just a place holder for margin;
     alternative is to use this for the main part of the page also! -->
</div>

<div class="subpage">
</div>

<div class="subpage">
</div>

You get the picture. Each "page" is just a section followed by a whopping amount of vertical space so that the next one doesn't show.

I'm using this trick to add "disambiguation navigation links" into a large document (more than 430 pages long in its letter-sized PDF form), which I would greatly prefer to keep as a single .html file. I emphasize that this is not a web site, but a document.

When the user clicks on a key word hyperlink in the document for which there are multiple possible topics associated with word, the user is taken a small navigation menu presenting several topic choices. This menu appears at top of what looks like a blank browser window, and so effectively looks like a page.

The only clue that the menu isn't a separate page is the state of the browser's vertical scroll bar, which is largely irrelevant in this navigation use case. If the user notices that, and starts scrolling around, the whole ruse is revealed, at which point the user will smile and appreciate not having been required to unpack a .zip file full of little pages and go hunting for the index.html.

Solution 2

It's actually possible to embed a HTML page within HTML. It can be done using the somewhat obscure data: URL in the href attribute. As a simple test, try sticking this somewhere in a HTML page:

<a href="data:text/html;charset=utf-8,<h3>FOO</h3>">blah</a>

In Firefox, I get a "blah" hyperlink, which navigates to a page showing the FOO heading. (Note that I don't have a fully formed HTML page here, just a HTML snippet; it's just a hello-world example).

The downside of this technique is that the entire target page is in the URL, which is stuffed into the browser's address input box.

If it is large, it could run into some issues, perhaps browser-specific; I don't have much experience with it.

Another disadvantage is that the entire HTML has to be properly escaped so that it can appear as the argument of the href attribute. Obviously, it cannot contain a plain double quote character anywhere.

A third disadvantage is that each such link has to replicates the data: material, since it isn't semantically a link at all, but a copy and paste embedding. It's not an attractive solution if the page-to-be-embeddded is large, and there are to be numerous links to it.

python replace single backslash with double backslash

Use escape characters: "full\\path\\here", "\\" and "\\\\"

php execute a background process

Assuming this is running on a Linux machine, I've always handled it like this:

exec(sprintf("%s > %s 2>&1 & echo $! >> %s", $cmd, $outputfile, $pidfile));

This launches the command $cmd, redirects the command output to $outputfile, and writes the process id to $pidfile.

That lets you easily monitor what the process is doing and if it's still running.

function isRunning($pid){
    try{
        $result = shell_exec(sprintf("ps %d", $pid));
        if( count(preg_split("/\n/", $result)) > 2){
            return true;
        }
    }catch(Exception $e){}

    return false;
}

Get final URL after curl is redirected

Thanks, that helped me. I made some improvements and wrapped that in a helper script "finalurl":

#!/bin/bash
curl $1 -s -L -I -o /dev/null -w '%{url_effective}'
  • -o output to /dev/null
  • -I don't actually download, just discover the final URL
  • -s silent mode, no progressbars

This made it possible to call the command from other scripts like this:

echo `finalurl http://someurl/`

Calling a php function by onclick event

Executing PHP functions by the onclick event is a cumbersome task and near impossible.

Instead you can redirect to another PHP page.

Say you are currently on a page one.php and you want to fetch some data from this php script process the data and show it in another page i.e. two.php you can do it by writing the following code <button onclick="window.location.href='two.php'">Click me</button>

Push method in React Hooks (useState)?

When you use useState, you can get an update method for the state item:

const [theArray, setTheArray] = useState(initialArray);

then, when you want to add a new element, you use that function and pass in the new array or a function that will create the new array. Normally the latter, since state updates are asynchronous and sometimes batched:

setTheArray(oldArray => [...oldArray, newElement]);

Sometimes you can get away without using that callback form, if you only update the array in handlers for certain specific user events like click (but not like mousemove):

setTheArray([...theArray, newElement]);

The events for which React ensures that rendering is flushed are the "discrete events" listed here.

Live Example (passing a callback into setTheArray):

_x000D_
_x000D_
const {useState, useCallback} = React;
function Example() {
    const [theArray, setTheArray] = useState([]);
    const addEntryClick = () => {
        setTheArray(oldArray => [...oldArray, `Entry ${oldArray.length}`]);
    };
    return [
        <input type="button" onClick={addEntryClick} value="Add" />,
        <div>{theArray.map(entry =>
          <div>{entry}</div>
        )}
        </div>
    ];
}

ReactDOM.render(
    <Example />,
    document.getElementById("root")
);
_x000D_
<div id="root"></div>
<script src="https://cdnjs.cloudflare.com/ajax/libs/react/16.8.1/umd/react.production.min.js"></script>
<script src="https://cdnjs.cloudflare.com/ajax/libs/react-dom/16.8.1/umd/react-dom.production.min.js"></script>
_x000D_
_x000D_
_x000D_

Because the only update to theArray in there is the one in a click event (one of the "discrete" events), I could get away with a direct update in addEntry:

_x000D_
_x000D_
const {useState, useCallback} = React;
function Example() {
    const [theArray, setTheArray] = useState([]);
    const addEntryClick = () => {
        setTheArray([...theArray, `Entry ${theArray.length}`]);
    };
    return [
        <input type="button" onClick={addEntryClick} value="Add" />,
        <div>{theArray.map(entry =>
          <div>{entry}</div>
        )}
        </div>
    ];
}

ReactDOM.render(
    <Example />,
    document.getElementById("root")
);
_x000D_
<div id="root"></div>
<script src="https://cdnjs.cloudflare.com/ajax/libs/react/16.8.1/umd/react.production.min.js"></script>
<script src="https://cdnjs.cloudflare.com/ajax/libs/react-dom/16.8.1/umd/react-dom.production.min.js"></script>
_x000D_
_x000D_
_x000D_

AngularJS - How can I do a redirect with a full page load?

After searching and giving hit and trial session I am able to solove it by first specifying url like

$window.location.href = '/#/home/stats';

then reload

$window.location.reload();

How do I display images from Google Drive on a website?

I have found a way to do it without using external sites.

<img src="https://drive.google.com/uc?export=view&id=XXX">

https://gist.github.com/evansims/f23e2f49e3d4be793038

<a href="https://drive.google.com/uc?export=view&id=XXX">
    <img src="https://drive.google.com/uc?export=view&id=XXX"
    style="width: 500px; max-width: 100%; height: auto"
    title="Click for the larger version." />
</a>

You'll need to grab the ID of the image: Click on “Open in new window” and get the ID from the URL.

Click on “Open in new window”

How to set layout_gravity programmatically?

KOTLIN setting more than one gravity on FrameLayout without changing size:

     // assign more than one gravity,Using the operator "or"
    var gravity = Gravity.RIGHT or Gravity.CENTER_VERTICAL
     // update gravity
    (pagerContainer.layoutParams as FrameLayout.LayoutParams).gravity = gravity
     // refresh layout
     pagerContainer.requestLayout()

Generating random, unique values C#

I'm calling NewNumber() regularly, but the problem is I often get repeated numbers.

Random.Next doesn't guarantee the number to be unique. Also your range is from 0 to 10 and chances are you will get duplicate values. May be you can setup a list of int and insert random numbers in the list after checking if it doesn't contain the duplicate. Something like:

public Random a = new Random(); // replace from new Random(DateTime.Now.Ticks.GetHashCode());
                                // Since similar code is done in default constructor internally
public List<int> randomList = new List<int>();
int MyNumber = 0;
private void NewNumber()
{
    MyNumber = a.Next(0, 10);
    if (!randomList.Contains(MyNumber))
        randomList.Add(MyNumber);
}

Responsive timeline UI with Bootstrap3

BootFlat

You can also try BootFlat, which has a section in their documentation specifically for crafting Timelines:

enter image description here

fatal: Not a git repository (or any of the parent directories): .git

The command has to be entered in the directory of the repository. The error is complaining that your current directory isn't a git repo

  1. Are you in the right directory? Does typing ls show the right files?
  2. Have you initialized the repository yet? Typed git init? (git-init documentation)

Either of those would cause your error.

Is Constructor Overriding Possible?

No it is not possible to override a constructor. If we try to do this then compiler error will come. And it is never possible in Java. Lets see the example. It will ask please write a return type o the method. means it will treat that overriden constructor as a method not as a constructor.

package com.sample.test;

class Animal{

    public static void showMessage()
    {
        System.out.println("we are in Animal class");
    }
}

class Dog extends Animal{

    public void DogShow() 
    {
        System.out.println("we are in Dog show class");
    } 

    public static void showMessage()
    {
        System.out.println("we are in overriddn method of dog class");
    }
}

public class AnimalTest { 

    public static void main(String [] args)
    {
        Animal animal = new Animal();
        animal.showMessage();

        Dog dog = new Dog();
        dog.DogShow();

        Animal animal2 = new Dog();
        animal2.showMessage();
    }

}

How to deny access to a file in .htaccess

Place the below line in your .htaccess file and replace the file name as you wish

RewriteRule ^(test\.php) - [F,L,NC]

Render HTML to PDF in Django site

I just whipped this up for CBV. Not used in production but generates a PDF for me. Probably needs work for the error reporting side of things but does the trick so far.

import StringIO
from cgi import escape
from xhtml2pdf import pisa
from django.http import HttpResponse
from django.template.response import TemplateResponse
from django.views.generic import TemplateView

class PDFTemplateResponse(TemplateResponse):

    def generate_pdf(self, retval):

        html = self.content

        result = StringIO.StringIO()
        rendering = pisa.pisaDocument(StringIO.StringIO(html.encode("ISO-8859-1")), result)

        if rendering.err:
            return HttpResponse('We had some errors<pre>%s</pre>' % escape(html))
        else:
            self.content = result.getvalue()

    def __init__(self, *args, **kwargs):
        super(PDFTemplateResponse, self).__init__(*args, mimetype='application/pdf', **kwargs)
        self.add_post_render_callback(self.generate_pdf)


class PDFTemplateView(TemplateView):
    response_class = PDFTemplateResponse

Used like:

class MyPdfView(PDFTemplateView):
    template_name = 'things/pdf.html'

Checking if a number is a prime number in Python

def isPrime(x):
    if x<2:
        return False
    for i in range(2,x):
        if not x%i:
           return False
    return True  

print isPrime(2)
True
print isPrime(3)
True
print isPrime(9)
False

In C#, what is the difference between public, private, protected, and having no access modifier?

enter image description here

using System;

namespace ClassLibrary1
{
    public class SameAssemblyBaseClass
    {
        public string publicVariable = "public";
        protected string protectedVariable = "protected";
        protected internal string protected_InternalVariable = "protected internal";
        internal string internalVariable = "internal";
        private string privateVariable = "private";
        public void test()
        {
            // OK
            Console.WriteLine(privateVariable);

            // OK
            Console.WriteLine(publicVariable);

            // OK
            Console.WriteLine(protectedVariable);

            // OK
            Console.WriteLine(internalVariable);

            // OK
            Console.WriteLine(protected_InternalVariable);
        }
    }

    public class SameAssemblyDerivedClass : SameAssemblyBaseClass
    {
        public void test()
        {
            SameAssemblyDerivedClass p = new SameAssemblyDerivedClass();

            // NOT OK
            // Console.WriteLine(privateVariable);

            // OK
            Console.WriteLine(p.publicVariable);

            // OK
            Console.WriteLine(p.protectedVariable);

            // OK
            Console.WriteLine(p.internalVariable);

            // OK
            Console.WriteLine(p.protected_InternalVariable);
        }
    }

    public class SameAssemblyDifferentClass
    {
        public SameAssemblyDifferentClass()
        {
            SameAssemblyBaseClass p = new SameAssemblyBaseClass();

            // OK
            Console.WriteLine(p.publicVariable);

            // OK
            Console.WriteLine(p.internalVariable);

            // NOT OK
            // Console.WriteLine(privateVariable);

            // Error : 'ClassLibrary1.SameAssemblyBaseClass.protectedVariable' is inaccessible due to its protection level
            //Console.WriteLine(p.protectedVariable);

            // OK
            Console.WriteLine(p.protected_InternalVariable);
        }
    }
}

 using System;
        using ClassLibrary1;
        namespace ConsoleApplication4

{
    class DifferentAssemblyClass
    {
        public DifferentAssemblyClass()
        {
            SameAssemblyBaseClass p = new SameAssemblyBaseClass();

            // NOT OK
            // Console.WriteLine(p.privateVariable);

            // NOT OK
            // Console.WriteLine(p.internalVariable);

            // OK
            Console.WriteLine(p.publicVariable);

            // Error : 'ClassLibrary1.SameAssemblyBaseClass.protectedVariable' is inaccessible due to its protection level
            // Console.WriteLine(p.protectedVariable);

            // Error : 'ClassLibrary1.SameAssemblyBaseClass.protected_InternalVariable' is inaccessible due to its protection level
            // Console.WriteLine(p.protected_InternalVariable);
        }
    }

    class DifferentAssemblyDerivedClass : SameAssemblyBaseClass
    {
        static void Main(string[] args)
        {
            DifferentAssemblyDerivedClass p = new DifferentAssemblyDerivedClass();

            // NOT OK
            // Console.WriteLine(p.privateVariable);

            // NOT OK
            //Console.WriteLine(p.internalVariable);

            // OK
            Console.WriteLine(p.publicVariable);

            // OK
            Console.WriteLine(p.protectedVariable);

            // OK
            Console.WriteLine(p.protected_InternalVariable);

            SameAssemblyDerivedClass dd = new SameAssemblyDerivedClass();
            dd.test();
        }
    }
}

Show a popup/message box from a Windows batch file

This will pop-up another Command Prompt window:

START CMD /C "ECHO My Popup Message && PAUSE"

How to download an entire directory and subdirectories using wget?

you can also use this command :

wget --mirror -pc --convert-links -P ./your-local-dir/ http://www.your-website.com

so that you get the exact mirror of the website you want to download

Adding up BigDecimals using Streams

Original answer

Yes, this is possible:

List<BigDecimal> bdList = new ArrayList<>();
//populate list
BigDecimal result = bdList.stream()
        .reduce(BigDecimal.ZERO, BigDecimal::add);

What it does is:

  1. Obtain a List<BigDecimal>.
  2. Turn it into a Stream<BigDecimal>
  3. Call the reduce method.

    3.1. We supply an identity value for addition, namely BigDecimal.ZERO.

    3.2. We specify the BinaryOperator<BigDecimal>, which adds two BigDecimal's, via a method reference BigDecimal::add.

Updated answer, after edit

I see that you have added new data, therefore the new answer will become:

List<Invoice> invoiceList = new ArrayList<>();
//populate
Function<Invoice, BigDecimal> totalMapper = invoice -> invoice.getUnit_price().multiply(invoice.getQuantity());
BigDecimal result = invoiceList.stream()
        .map(totalMapper)
        .reduce(BigDecimal.ZERO, BigDecimal::add);

It is mostly the same, except that I have added a totalMapper variable, that has a function from Invoice to BigDecimal and returns the total price of that invoice.

Then I obtain a Stream<Invoice>, map it to a Stream<BigDecimal> and then reduce it to a BigDecimal.

Now, from an OOP design point I would advice you to also actually use the total() method, which you have already defined, then it even becomes easier:

List<Invoice> invoiceList = new ArrayList<>();
//populate
BigDecimal result = invoiceList.stream()
        .map(Invoice::total)
        .reduce(BigDecimal.ZERO, BigDecimal::add);

Here we directly use the method reference in the map method.

What is "406-Not Acceptable Response" in HTTP?

You can also receive a 406 response when invalid cookies are stored or referenced in the browser - for example, when running a Rails server in Dev mode locally.

If you happened to run two different projects on the same port, the browser might reference a cookie from a different localhost session.

This has happened to me...tripped me up for a minute. Looking in browser > Developer Mode > Network showed it.

Validate fields after user has left a field

Here is an example using ng-messages (available in angular 1.3) and a custom directive.

Validation message is displayed on blur for the first time user leaves the input field, but when he corrects the value, validation message is removed immediately (not on blur anymore).

JavaScript

myApp.directive("validateOnBlur", [function() {
    var ddo = {
        restrict: "A",
        require: "ngModel",
        scope: {},
        link: function(scope, element, attrs, modelCtrl) {
            element.on('blur', function () {
                modelCtrl.$showValidationMessage = modelCtrl.$dirty;
                scope.$apply();
            });
        }
    };
    return ddo;
}]);

HTML

<form name="person">
    <input type="text" ng-model="item.firstName" name="firstName" 
        ng-minlength="3" ng-maxlength="20" validate-on-blur required />
    <div ng-show="person.firstName.$showValidationMessage" ng-messages="person.firstName.$error">
        <span ng-message="required">name is required</span>
        <span ng-message="minlength">name is too short</span>
        <span ng-message="maxlength">name is too long</span>
    </div>
</form>

PS. Don't forget to download and include ngMessages in your module:

var myApp = angular.module('myApp', ['ngMessages']);

git discard all changes and pull from upstream

You can do it in a single command:

git fetch --all && git reset --hard origin/master

Or in a pair of commands:

git fetch --all
git reset --hard origin/master

Note than you will lose ALL your local changes

How to calculate the sentence similarity using word2vec model of gensim with python

Since you're using gensim, you should probably use it's doc2vec implementation. doc2vec is an extension of word2vec to the phrase-, sentence-, and document-level. It's a pretty simple extension, described here

http://cs.stanford.edu/~quocle/paragraph_vector.pdf

Gensim is nice because it's intuitive, fast, and flexible. What's great is that you can grab the pretrained word embeddings from the official word2vec page and the syn0 layer of gensim's Doc2Vec model is exposed so that you can seed the word embeddings with these high quality vectors!

GoogleNews-vectors-negative300.bin.gz (as linked in Google Code)

I think gensim is definitely the easiest (and so far for me, the best) tool for embedding a sentence in a vector space.

There exist other sentence-to-vector techniques than the one proposed in Le & Mikolov's paper above. Socher and Manning from Stanford are certainly two of the most famous researchers working in this area. Their work has been based on the principle of compositionally - semantics of the sentence come from:

1. semantics of the words

2. rules for how these words interact and combine into phrases

They've proposed a few such models (getting increasingly more complex) for how to use compositionality to build sentence-level representations.

2011 - unfolding recursive autoencoder (very comparatively simple. start here if interested)

2012 - matrix-vector neural network

2013 - neural tensor network

2015 - Tree LSTM

his papers are all available at socher.org. Some of these models are available, but I'd still recommend gensim's doc2vec. For one, the 2011 URAE isn't particularly powerful. In addition, it comes pretrained with weights suited for paraphrasing news-y data. The code he provides does not allow you to retrain the network. You also can't swap in different word vectors, so you're stuck with 2011's pre-word2vec embeddings from Turian. These vectors are certainly not on the level of word2vec's or GloVe's.

Haven't worked with the Tree LSTM yet, but it seems very promising!

tl;dr Yeah, use gensim's doc2vec. But other methods do exist!

Is "else if" faster than "switch() case"?

Another thing to consider: is this really the bottleneck of your application? There are extremely rare cases when optimization of this sort is really required. Most of the time you can get way better speedups by rethinking your algorithms and data structures.

Converting byte array to string in javascript

The simplest solution I've found is:

var text = atob(byteArray);

Get width/height of SVG element

From Firefox 33 onwards you can call getBoundingClientRect() and it will work normally, i.e. in the question above it will return 300 x 100.

Firefox 33 will be released on 14th October 2014 but the fix is already in Firefox nightlies if you want to try it out.

How do I get the "id" after INSERT into MySQL database with Python?

Also, cursor.lastrowid (a dbapi/PEP249 extension supported by MySQLdb):

>>> import MySQLdb
>>> connection = MySQLdb.connect(user='root')
>>> cursor = connection.cursor()
>>> cursor.execute('INSERT INTO sometable VALUES (...)')
1L
>>> connection.insert_id()
3L
>>> cursor.lastrowid
3L
>>> cursor.execute('SELECT last_insert_id()')
1L
>>> cursor.fetchone()
(3L,)
>>> cursor.execute('select @@identity')
1L
>>> cursor.fetchone()
(3L,)

cursor.lastrowid is somewhat cheaper than connection.insert_id() and much cheaper than another round trip to MySQL.

How to get a list of programs running with nohup

When I started with $ nohup storm dev-zookeper ,

METHOD1 : using jobs,

prayagupd@prayagupd:/home/vmfest# jobs -l
[1]+ 11129 Running                 nohup ~/bin/storm/bin/storm dev-zookeeper &

METHOD2 : using ps command.

$ ps xw
PID  TTY      STAT   TIME COMMAND
1031 tty1     Ss+    0:00 /sbin/getty -8 38400 tty1
10582 ?        S      0:01 [kworker/0:0]
10826 ?        Sl     0:18 java -server -Dstorm.options= -Dstorm.home=/root/bin/storm -Djava.library.path=/usr/local/lib:/opt/local/lib:/usr/lib -Dsto
10853 ?        Ss     0:00 sshd: vmfest [priv] 

TTY column with ? => nohup running programs.

Description

  • TTY column = the terminal associated with the process
  • STAT column = state of a process
    • S = interruptible sleep (waiting for an event to complete)
    • l = is multi-threaded (using CLONE_THREAD, like NPTL pthreads do)

Reference

$ man ps # then search /PROCESS STATE CODES

How to create a simple http proxy in node.js?

Here's a proxy server using request that handles redirects. Use it by hitting your proxy URL http://domain.com:3000/?url=[your_url]

var http = require('http');
var url = require('url');
var request = require('request');

http.createServer(onRequest).listen(3000);

function onRequest(req, res) {

    var queryData = url.parse(req.url, true).query;
    if (queryData.url) {
        request({
            url: queryData.url
        }).on('error', function(e) {
            res.end(e);
        }).pipe(res);
    }
    else {
        res.end("no url found");
    }
}

Replacing a character from a certain index

You can also Use below method if you have to replace string between specific index

def Replace_Substring_Between_Index(singleLine,stringToReplace='',startPos=0,endPos=1):
    try:
       singleLine = singleLine[:startPos]+stringToReplace+singleLine[endPos:]
    except Exception as e:
        exception="There is Exception at this step while calling replace_str_index method, Reason = " + str(e)
        BuiltIn.log_to_console(exception)
    return singleLine

Looping through GridView rows and Checking Checkbox Control

you have to iterate gridview Rows

for (int count = 0; count < grd.Rows.Count; count++)
{
    if (((CheckBox)grd.Rows[count].FindControl("yourCheckboxID")).Checked)
    {     
      ((Label)grd.Rows[count].FindControl("labelID")).Text
    }
}

How can I detect if this dictionary key exists in C#?

Here is a little something I cooked up today. Seems to work for me. Basically you override the Add method in your base namespace to do a check and then call the base's Add method in order to actually add it. Hope this works for you

using System;
using System.Collections.Generic;
using System.Collections;

namespace Main
{
    internal partial class Dictionary<TKey, TValue> : System.Collections.Generic.Dictionary<TKey, TValue>
    {
        internal new virtual void Add(TKey key, TValue value)
        {   
            if (!base.ContainsKey(key))
            {
                base.Add(key, value);
            }
        }
    }

    internal partial class List<T> : System.Collections.Generic.List<T>
    {
        internal new virtual void Add(T item)
        {
            if (!base.Contains(item))
            {
                base.Add(item);
            }
        }
    }

    public class Program
    {
        public static void Main()
        {
            Dictionary<int, string> dic = new Dictionary<int, string>();
            dic.Add(1,"b");
            dic.Add(1,"a");
            dic.Add(2,"c");
            dic.Add(1, "b");
            dic.Add(1, "a");
            dic.Add(2, "c");

            string val = "";
            dic.TryGetValue(1, out val);

            Console.WriteLine(val);
            Console.WriteLine(dic.Count.ToString());


            List<string> lst = new List<string>();
            lst.Add("b");
            lst.Add("a");
            lst.Add("c");
            lst.Add("b");
            lst.Add("a");
            lst.Add("c");

            Console.WriteLine(lst[2]);
            Console.WriteLine(lst.Count.ToString());
        }
    }
}

no module named zlib

After you install the missing zlib dev package you can also use pythonbrew to uninstall and then reinstall the version of python you wanted and it seems like it picks up the new package to compile to correct abilities. This way you can keep using pythonbrew and don't have to do the compilation yourself (though it isn't that difficult)

How to remove last n characters from a string in Bash?

First, it's usually better to be explicit about your intent. So if you know the string ends in .rtf, and you want to remove that .rtf, you can just use var2=${var%.rtf}. One potentially-useful aspect of this approach is that if the string doesn't end in .rtf, it is not changed at all; var2 will contain an unmodified copy of var.

If you want to remove a filename suffix but don't know or care exactly what it is, you can use var2=${var%.*} to remove everything starting with the last .. Or, if you only want to keep everything up to but not including the first ., you can use var2=${var%%.*}. Those options have the same result if there's only one ., but if there might be more than one, you get to pick which end of the string to work from. On the other hand, if there's no . in the string at all, var2 will again be an unchanged copy of var.

If you really want to always remove a specific number of characters, here are some options.

You tagged this bash specifically, so we'll start with bash builtins. The one which has worked the longest is the same suffix-removal syntax I used above: to remove four characters, use var2=${var%????}. Or to remove four characters only if the first one is a dot, use var2=${var%.???}, which is like var2=${var%.*} but only removes the suffix if the part after the dot is exactly three characters. As you can see, to count characters this way, you need one question mark per unknown character removed, so this approach gets unwieldy for larger substring lengths.

An option in newer shell versions is substring extraction: var2=${var:0:${#var}-4}. Here you can put any number in place of the 4 to remove a different number of characters. The ${#var} is replaced by the length of the string, so this is actually asking to extract and keep (length - 4) characters starting with the first one (at index 0). With this approach, you lose the option to make the change only if the string matches a pattern; no matter what the actual value of the string is, the copy will include all but its last four characters.

Bash lets you leave the start index out; it defaults to 0, so you can shorten that to just var2=${var::${#var}-4}. In fact, newer versions of bash (specifically 4+, which means the one that ships with MacOS won't work) recognize negative lengths as end indexes counting back from the end of the string, so you can get rid of the string-length expression, too: var2=${var::-4}.

If you're not actually using bash but some other POSIX-type shell, the pattern-based suffix removal with % will still work – even in plain old dash, where the index-based substring extraction won't. Ksh and zsh do both support substring extraction, but require the explicit 0 start index; zsh also supports the negative end index, while ksh requires the length expression. Note that zsh, which indexes arrays starting at 1, nonetheless indexes strings starting at 0 if you use this bash-compatible syntax; but you can also treat parameters as arrays of characters, in which case it uses a 1-based count and expects a start and inclusive end position in brackets: var2=$var[1,-5].

Instead of using built-in shell parameter expansion, you can of course run some utility program to modify the string and capture its output with command substitution. There are several commands that will work; one is var2=$(sed 's/.\{4\}$//' <<<"$var").

PKIX path building failed in Java application

If you are using Eclipse just cross check in Eclipse Windows--> preferences---->java---> installed JREs is pointing the current JRE and the JRE where you have configured your certificate. If not remove the JRE and add the jre where your certificate is installed

How to analyze a JMeter summary report?

Short explanation looks like:

  1. Sample - number of requests sent
  2. Avg - an Arithmetic mean for all responses (sum of all times / count)
  3. Minimal response time (ms)
  4. Maximum response time (ms)
  5. Deviation - see Standard Deviation article
  6. Error rate - percentage of failed tests
  7. Throughput - how many requests per second does your server handle. Larger is better.
  8. KB/Sec - self expalanatory
  9. Avg. Bytes - average response size

If you having troubles with interpreting results you could try BM.Sense results analysis service

iOS change navigation bar title font and color

Swift 4.2

self.navigationController?.navigationBar.titleTextAttributes =
        [NSAttributedString.Key.foregroundColor: UIColor.white,
         NSAttributedString.Key.font: UIFont(name: "LemonMilklight", size: 21)!]

R dates "origin" must be supplied

If you have both date and time information in the numeric value, then use as.POSIXct. Data.table package IDateTime format is such a case. If you use fwrite to save a file, the package automatically converts date-times to idatetime format which is unix time. To convert back to normal format following can be done.

Example: Let's say you have a unix time stamp with date and time info: 1442866615

> as.POSIXct(1442866615,origin="1970-01-01")
[1] "2015-09-21 16:16:54 EDT"

jQuery Ajax File Upload

Simple Upload Form

_x000D_
_x000D_
 <script>_x000D_
   //form Submit_x000D_
   $("form").submit(function(evt){  _x000D_
      evt.preventDefault();_x000D_
      var formData = new FormData($(this)[0]);_x000D_
   $.ajax({_x000D_
       url: 'fileUpload',_x000D_
       type: 'POST',_x000D_
       data: formData,_x000D_
       async: false,_x000D_
       cache: false,_x000D_
       contentType: false,_x000D_
       enctype: 'multipart/form-data',_x000D_
       processData: false,_x000D_
       success: function (response) {_x000D_
         alert(response);_x000D_
       }_x000D_
   });_x000D_
   return false;_x000D_
 });_x000D_
</script>
_x000D_
<!--Upload Form-->_x000D_
<form>_x000D_
  <table>_x000D_
    <tr>_x000D_
      <td colspan="2">File Upload</td>_x000D_
    </tr>_x000D_
    <tr>_x000D_
      <th>Select File </th>_x000D_
      <td><input id="csv" name="csv" type="file" /></td>_x000D_
    </tr>_x000D_
    <tr>_x000D_
      <td colspan="2">_x000D_
        <input type="submit" value="submit"/> _x000D_
      </td>_x000D_
    </tr>_x000D_
  </table>_x000D_
</form>
_x000D_
_x000D_
_x000D_

Where does Console.WriteLine go in ASP.NET?

The TraceContext object in ASP.NET writes to the DefaultTraceListener which outputs to the host process’ standard output. Rather than using Console.Write(), if you use Trace.Write, output will go to the standard output of the process.

You could use the System.Diagnostics.Process object to get the ASP.NET process for your site and monitor standard output using the OutputDataRecieved event.

Centering a canvas

Resizing canvas using css is not a good idea. It should be done using Javascript. See the below function which does it

function setCanvas(){

   var canvasNode = document.getElementById('xCanvas');

   var pw = canvasNode.parentNode.clientWidth;
   var ph = canvasNode.parentNode.clientHeight;

   canvasNode.height = pw * 0.8 * (canvasNode.height/canvasNode.width);  
   canvasNode.width = pw * 0.8;
   canvasNode.style.top = (ph-canvasNode.height)/2 + "px";
   canvasNode.style.left = (pw-canvasNode.width)/2 + "px";


}

demo here : http://jsfiddle.net/9Rmwt/11/show/

.

Javascript date regex DD/MM/YYYY

If you are in Javascript already, couldn't you just use Date.Parse() to validate a date instead of using regEx.

RegEx for date is actually unwieldy and hard to get right especially with leap years and all.

Add day(s) to a Date object

date.setTime( date.getTime() + days * 86400000 );

What's the difference between a proxy server and a reverse proxy server?

Some diagrams might help:

Forward proxy

Forward proxy

Reverse proxy

Reverse proxy

For loop in multidimensional javascript array

var cubes = [["string", "string"], ["string", "string"]];

for(var i = 0; i < cubes.length; i++) {
    for(var j = 0; j < cubes[i].length; j++) {
        console.log(cubes[i][j]);
    }
}

React - Preventing Form Submission

preventDefault is what you're looking for. To just block the button from submitting

<Button onClick={this.onClickButton} ...

code

onClickButton (event) {
  event.preventDefault();
}

If you have a form which you want to handle in a custom way you can capture a higher level event onSubmit which will also stop that button from submitting.

<form onSubmit={this.onSubmit}>

and above in code

onSubmit (event) {
  event.preventDefault();

  // custom form handling here
}

What's the best way to center your HTML email content in the browser window (or email client preview pane)?

CSS in emails is a pain. You'll probably need tables unfortunately, because CSS is not greatly supported in all email clients.

That said, use an HTML Transitional DOCTYPE, not XHTML, and use <center>.

Reading json files in C++

Here is another easier possibility to read in a json file:

#include "json/json.h"

std::ifstream file_input("input.json");
Json::Reader reader;
Json::Value root;
reader.parse(file_input, root);
cout << root;

You can then get the values like this:

cout << root["key"]

Finding first and last index of some value in a list in Python

Perhaps the two most efficient ways to find the last index:

def rindex(lst, value):
    lst.reverse()
    i = lst.index(value)
    lst.reverse()
    return len(lst) - i - 1
def rindex(lst, value):
    return len(lst) - operator.indexOf(reversed(lst), value) - 1

Both take only O(1) extra space and the two in-place reversals of the first solution are much faster than creating a reverse copy. Let's compare it with the other solutions posted previously:

def rindex(lst, value):
    return len(lst) - lst[::-1].index(value) - 1

def rindex(lst, value):
    return len(lst) - next(i for i, val in enumerate(reversed(lst)) if val == value) - 1

Benchmark results, my solutions are the red and green ones: unshuffled, full range

This is for searching a number in a list of a million numbers. The x-axis is for the location of the searched element: 0% means it's at the start of the list, 100% means it's at the end of the list. All solutions are fastest at location 100%, with the two reversed solutions taking pretty much no time for that, the double-reverse solution taking a little time, and the reverse-copy taking a lot of time.

A closer look at the right end: unshuffled, tail part

At location 100%, the reverse-copy solution and the double-reverse solution spend all their time on the reversals (index() is instant), so we see that the two in-place reversals are about seven times as fast as creating the reverse copy.

The above was with lst = list(range(1_000_000, 2_000_001)), which pretty much creates the int objects sequentially in memory, which is extremely cache-friendly. Let's do it again after shuffling the list with random.shuffle(lst) (probably less realistic, but interesting):

shuffled list, full range

shuffled list, tail part

All got a lot slower, as expected. The reverse-copy solution suffers the most, at 100% it now takes about 32 times (!) as long as the double-reverse solution. And the enumerate-solution is now second-fastest only after location 98%.

Overall I like the operator.indexOf solution best, as it's the fastest one for the last half or quarter of all locations, which are perhaps the more interesting locations if you're actually doing rindex for something. And it's only a bit slower than the double-reverse solution in earlier locations.

All benchmarks done with CPython 3.9.0 64-bit on Windows 10 Pro 1903 64-bit.

C# Creating and using Functions

static void Main(string[] args)
    {
        Console.WriteLine("geef een leeftijd");
        int a = Convert.ToInt32(Console.ReadLine());

        Console.WriteLine("geef een leeftijd");
        int b = Convert.ToInt32(Console.ReadLine());

        int einde = Sum(a, b);
        Console.WriteLine(einde);
    }
    static int Sum(int x, int y)
    {
        int result = x + y;
        return result;
    }

Why does an onclick property set with setAttribute fail to work in IE?

Or you could use jQuery and avoid all those issues:

var execBtn = $("<input>", {
       type: "button",
       id: "execBtn",
       value: "Execute"
    })
    .click(runCommand);        

jQuery will take care of all the cross-browser issues as well.

SQL Server - after insert trigger - update another column in the same table

Use a computed column instead. It is almost always a better idea to use a computed column than a trigger.

See Example below of a computed column using the UPPER function:

create table #temp (test varchar (10), test2 AS upper(test))
insert #temp (test)
values ('test')
select * from #temp

And not to sound like a broken record or anything, but this is critically important. Never write a trigger that will not work correctly on multiple record inserts/updates/deletes. This is an extremely poor practice as sooner or later one of these will happen and your trigger will cause data integrity problems asw it won't fail precisely it will only run the process on one of the records. This can go a long time until someone discovers the mess and by themn it is often impossible to correctly fix the data.

Why should I use a pointer rather than the object itself?

There are many use cases for pointers.

Polymorphic behavior. For polymorphic types, pointers (or references) are used to avoid slicing:

class Base { ... };
class Derived : public Base { ... };

void fun(Base b) { ... }
void gun(Base* b) { ... }
void hun(Base& b) { ... }

Derived d;
fun(d);    // oops, all Derived parts silently "sliced" off
gun(&d);   // OK, a Derived object IS-A Base object
hun(d);    // also OK, reference also doesn't slice

Reference semantics and avoiding copying. For non-polymorphic types, a pointer (or a reference) will avoid copying a potentially expensive object

Base b;
fun(b);  // copies b, potentially expensive 
gun(&b); // takes a pointer to b, no copying
hun(b);  // regular syntax, behaves as a pointer

Note that C++11 has move semantics that can avoid many copies of expensive objects into function argument and as return values. But using a pointer will definitely avoid those and will allow multiple pointers on the same object (whereas an object can only be moved from once).

Resource acquisition. Creating a pointer to a resource using the new operator is an anti-pattern in modern C++. Use a special resource class (one of the Standard containers) or a smart pointer (std::unique_ptr<> or std::shared_ptr<>). Consider:

{
    auto b = new Base;
    ...       // oops, if an exception is thrown, destructor not called!
    delete b;
}

vs.

{
    auto b = std::make_unique<Base>();
    ...       // OK, now exception safe
}

A raw pointer should only be used as a "view" and not in any way involved in ownership, be it through direct creation or implicitly through return values. See also this Q&A from the C++ FAQ.

More fine-grained life-time control Every time a shared pointer is being copied (e.g. as a function argument) the resource it points to is being kept alive. Regular objects (not created by new, either directly by you or inside a resource class) are destroyed when going out of scope.

Get the current date and time

Get Current DateTime

Now.ToShortDateString()
DateTime.Now
Today.Now

Disable Logback in SpringBoot

Just add logback.xml configuration in your classpath and add all your configuration with root appender added. Once the Spring boot completes the bean loading, it will start logging based on your configuration.

How to get value by key from JObject?

Try this:

private string GetJArrayValue(JObject yourJArray, string key)
{
    foreach (KeyValuePair<string, JToken> keyValuePair in yourJArray)
    {
        if (key == keyValuePair.Key)
        {
            return keyValuePair.Value.ToString();
        }
    }
}

Calling a particular PHP function on form submit

Assuming that your script is named x.php, try this

<?php 
   function display($s) {
      echo $s;
   }
?>
<html>
    <body>
        <form method="post" action="x.php">
            <input type="text" name="studentname">
            <input type="submit" value="click">
        </form>
        <?php
           if($_SERVER['REQUEST_METHOD']=='POST')
           {
               display();
           } 
        ?>
    </body>
</html>

How can I set the opacity or transparency of a Panel in WinForms?

Based on information found at http://www.windows-tech.info/3/53ee08e46d9cb138.php, I was able to achieve a translucent panel control using the following code.

public class TransparentPanel : Panel
{
    protected override CreateParams CreateParams
    {
        get
        {
            var cp = base.CreateParams;
            cp.ExStyle |= 0x00000020; // WS_EX_TRANSPARENT

            return cp;
        }
    }

    protected override void OnPaint(PaintEventArgs e) =>
        e.Graphics.FillRectangle(new SolidBrush(this.BackColor), this.ClientRectangle);
}

The caveat is that any controls that are added to the panel have an opaque background. Nonetheless, the translucent panel was useful for me to block off parts of my WinForms application so that users focus was shifted to the appropriate area of the application.

overlay opaque div over youtube iframe

Note that the wmode=transparent fix only works if it's first so

http://www.youtube.com/embed/K3j9taoTd0E?wmode=transparent&rel=0

Not

http://www.youtube.com/embed/K3j9taoTd0E?rel=0&wmode=transparent

Getting strings recognized as variable names in R

The basic answer to the question in the title is eval(as.symbol(variable_name_as_string)) as Josh O'Brien uses. e.g.

var.name = "x"
assign(var.name, 5)
eval(as.symbol(var.name)) # outputs 5

Or more simply:

get(var.name) # 5

glm rotate usage in Opengl

GLM has good example of rotation : http://glm.g-truc.net/code.html

glm::mat4 Projection = glm::perspective(45.0f, 4.0f / 3.0f, 0.1f, 100.f);
glm::mat4 ViewTranslate = glm::translate(
    glm::mat4(1.0f),
    glm::vec3(0.0f, 0.0f, -Translate)
);
glm::mat4 ViewRotateX = glm::rotate(
    ViewTranslate,
    Rotate.y,
    glm::vec3(-1.0f, 0.0f, 0.0f)
);
glm::mat4 View = glm::rotate(
    ViewRotateX,
    Rotate.x,
    glm::vec3(0.0f, 1.0f, 0.0f)
);
glm::mat4 Model = glm::scale(
    glm::mat4(1.0f),
    glm::vec3(0.5f)
);
glm::mat4 MVP = Projection * View * Model;
glUniformMatrix4fv(LocationMVP, 1, GL_FALSE, glm::value_ptr(MVP));

PHP 5.4 Call-time pass-by-reference - Easy fix available?

You should be denoting the call by reference in the function definition, not the actual call. Since PHP started showing the deprecation errors in version 5.3, I would say it would be a good idea to rewrite the code.

From the documentation:

There is no reference sign on a function call - only on function definitions. Function definitions alone are enough to correctly pass the argument by reference. As of PHP 5.3.0, you will get a warning saying that "call-time pass-by-reference" is deprecated when you use & in foo(&$a);.

For example, instead of using:

// Wrong way!
myFunc(&$arg);               # Deprecated pass-by-reference argument
function myFunc($arg) { }

Use:

// Right way!
myFunc($var);                # pass-by-value argument
function myFunc(&$arg) { }

How to `wget` a list of URLs in a text file?

Run it in parallel with

cat text_file.txt | parallel --gnu "wget {}"

Difference between Destroy and Delete

Yes there is a major difference between the two methods Use delete_all if you want records to be deleted quickly without model callbacks being called

If you care about your models callbacks then use destroy_all

From the official docs

http://apidock.com/rails/ActiveRecord/Base/destroy_all/class

destroy_all(conditions = nil) public

Destroys the records matching conditions by instantiating each record and calling its destroy method. Each object’s callbacks are executed (including :dependent association options and before_destroy/after_destroy Observer methods). Returns the collection of objects that were destroyed; each will be frozen, to reflect that no changes should be made (since they can’t be persisted).

Note: Instantiation, callback execution, and deletion of each record can be time consuming when you’re removing many records at once. It generates at least one SQL DELETE query per record (or possibly more, to enforce your callbacks). If you want to delete many rows quickly, without concern for their associations or callbacks, use delete_all instead.

Angularjs: input[text] ngChange fires while the value is changing

This is about recent additions to AngularJS, to serve as future answer (also for another question).

Angular newer versions (now in 1.3 beta), AngularJS natively supports this option, using ngModelOptions, like

ng-model-options="{ updateOn: 'default blur', debounce: { default: 500, blur: 0 } }"

NgModelOptions docs

Example:

<input type="text" name="username"
       ng-model="user.name"
       ng-model-options="{updateOn: 'default blur', debounce: {default: 500, blur: 0} }" />

Command copy exited with code 4 when building - Visual Studio restart solves it

I have also faced this problem.Double check the result in the error window.

In my case, a tailing \ was crashing xcopy (as I was using $(TargetDir)). In my case $(SolutionDir)..\bin. If you're using any other output, this needs to be adjusted.

Also note that start xcopy does not fix it, if the error is gone after compiling. It might have just been suppressed by the command line and no file has actually been copied!

You can btw manually execute your xcopy commands in a command shell. You will get more details when executing them there, pointing you in the right direction.

Simple DateTime sql query

SELECT * 
  FROM TABLENAME 
 WHERE [DateTime] >= '2011-04-12 12:00:00 AM'
   AND [DateTime] <= '2011-05-25 3:35:04 AM'

If this doesn't work, please script out your table and post it here. this will help us get you the correct answer quickly.

How can I check if a Perl array contains a particular value?

@eakssjo's benchmark is broken - measures creating hashes in loop vs creating regexes in loop. Fixed version (plus I've added List::Util::first and List::MoreUtils::any):

use List::Util qw(first);
use List::MoreUtils qw(any);
use Benchmark;

my @list = ( 1..10_000 );
my $hit = 5_000;
my $hit_regex = qr/^$hit$/; # precompute regex
my %params;
$params{$_} = 1 for @list;  # precompute hash
timethese(
    100_000, {
        'any' => sub {
            die unless ( any { $hit_regex } @list );
        },
        'first' => sub {
            die unless ( first { $hit_regex } @list );
        },
        'grep' => sub {
            die unless ( grep { $hit_regex } @list );
        },
        'hash' => sub {
            die unless ( $params{$hit} );
        },
    });

And result (it's for 100_000 iterations, ten times more than in @eakssjo's answer):

Benchmark: timing 100000 iterations of any, first, grep, hash...
       any:  0 wallclock secs ( 0.67 usr +  0.00 sys =  0.67 CPU) @ 149253.73/s (n=100000)
     first:  1 wallclock secs ( 0.63 usr +  0.01 sys =  0.64 CPU) @ 156250.00/s (n=100000)
      grep: 42 wallclock secs (41.95 usr +  0.08 sys = 42.03 CPU) @ 2379.25/s (n=100000)
      hash:  0 wallclock secs ( 0.01 usr +  0.00 sys =  0.01 CPU) @ 10000000.00/s (n=100000)
            (warning: too few iterations for a reliable count)

how to realize countifs function (excel) in R

Easy peasy. Your data frame will look like this:

df <- data.frame(sex=c('M','F','M'),
                 occupation=c('Student','Analyst','Analyst'))

You can then do the equivalent of a COUNTIF by first specifying the IF part, like so:

df$sex == 'M'

This will give you a boolean vector, i.e. a vector of TRUE and FALSE. What you want is to count the observations for which the condition is TRUE. Since in R TRUE and FALSE double as 1 and 0 you can simply sum() over the boolean vector. The equivalent of COUNTIF(sex='M') is therefore

sum(df$sex == 'M')

Should there be rows in which the sex is not specified the above will give back NA. In that case, if you just want to ignore the missing observations use

sum(df$sex == 'M', na.rm=TRUE)

Delete specific line from a text file?

One way to do it if the file is not very big is to load all the lines into an array:

string[] lines = File.ReadAllLines("filename.txt");
string[] newLines = RemoveUnnecessaryLine(lines);
File.WriteAllLines("filename.txt", newLines);

The number of method references in a .dex file cannot exceed 64k API 17

This error can also occur when you load all google play services apis when you only using afew.

As stated by google:"In versions of Google Play services prior to 6.5, you had to compile the entire package of APIs into your app. In some cases, doing so made it more difficult to keep the number of methods in your app (including framework APIs, library methods, and your own code) under the 65,536 limit.

From version 6.5, you can instead selectively compile Google Play service APIs into your app."

For example when your app needs play-services-maps ,play-services-location .You need to add only the two apis in your build.gradle file at app level as show below:

compile 'com.google.android.gms:play-services-maps:10.2.1'
compile 'com.google.android.gms:play-services-location:10.2.1'

Instead of:

compile 'com.google.android.gms:play-services:10.2.1'

For full documentation and list of google play services apis click here

The AWS Access Key Id does not exist in our records

You may have configured AWS credentials correctly, but using these credentials, you may be connecting to some specific S3 endpoint (as was the case with me).

Instead of using:

aws s3 ls

try using:

aws --endpoint-url=https://<your_s3_endpoint_url> s3 ls

Hope this helps those facing the similar problem.

Offline Speech Recognition In Android (JellyBean)

I would like to improve the guide that the answer https://stackoverflow.com/a/17674655/2987828 sends to its users, with images. It is the sentence "For those that it doesn't, this is the ‘guide’ I supply them with." that I want to improve.

The user should click on the four buttons highlighted in blue in these images:

Go to your Android Application Settings, select Languages and input, edit Settings of Google Voice typing, select Download Offline speech recognition, select your languages in the ALL tab.

Then the user can select any desired languages. When the download is done, he should disconnect from network, and then click on the "microphone" button of the keyboard.

It worked for me (android 4.1.2), then language recognition worked out of the box, without rebooting. I can now dictates instructions to the shell of Terminal Emulator ! And it is twice faster offline than online, on a padfone 2 from ASUS.

These images are licensed under cc by-sa 3.0 with attribution required to stackoverflow.com/a/21329845/2987828 ; you may hence add these images anywhere along with this attribution.

(This the standard policy of all images and texts at stackoverflow.com)

What is a 'workspace' in Visual Studio Code?

The main utility of a workspace (and maybe the only one) is to allow to add multiple independent folders that compounds a project. For example:

- WorkspaceProjectX  
-- ApiFolder   (maybe /usr/share/www/api)  
-- DocsFolder  (maybe /home/user/projx/html/docs)  
-- WebFolder   (maybe /usr/share/www/web)

So you can group those in a work space for a specific project instead of have to open multiple folders windows.

You can learn more here.

Java SimpleDateFormat for time zone with a colon separator?

Try this, its work for me:

Date date = javax.xml.bind.DatatypeConverter.parseDateTime("2013-06-01T12:45:01+04:00").getTime();

In Java 8:

OffsetDateTime dt = OffsetDateTime.parse("2010-03-01T00:00:00-08:00");

Simple GUI Java calculator

Somewhere you have to keep track of what button had been pressed. When things happen, you need to store something in a variable so you can recall the information or it's gone forever.

When someone pressed one of the operator buttons, don't just let them type in another value. Save the operator symbol, then let them type in another value. You could literally just have a String operator that gets the text of the operator button pressed. Then, when the equals button is pressed, you have to check to see which operator you stored. You could do this with an if/else if/else chain.

So, in your symbol's button press event, store the symbol text in a variable, then, in the = button press event, check to see which symbol is in the variable and act accordingly.

Alternatively, if you feel comfortable enough with enums (looks like you're just starting, so if you're not to that point yet, ignore this), you could have an enumeration of symbols that lets you check symbols easily with a switch.

Responsive Bootstrap Jumbotron Background Image

This is how I do :

_x000D_
_x000D_
<div class="jumbotron" style="background: url(img/bg.jpg) no-repeat center center fixed; -webkit-background-size: cover; -moz-background-size: cover; -o-background-size: cover; background-size: cover;">_x000D_
  <h1>Hello</h1>_x000D_
</div>
_x000D_
_x000D_
_x000D_

Can overridden methods differ in return type?

Broadly speaking yes return type of overriding method can be different. But it's not straight forward as there are some cases involved in this.

Case 1: If the return type is a primitive data type or void.

Output: If the return type is void or primitive then the data type of parent class method and overriding method should be the same. e.g. if the return type is int, float, string then it should be same

Case 2: If the return type is derived data type:

Output: If the return type of the parent class method is derived type then the return type of the overriding method is the same derived data type of subclass to the derived data type. e.g. Suppose I have a class A, B is a subclass to A, C is a subclass to B and D is a subclass to C; then if the super class is returning type A then the overriding method in subclass can return either A, or B/C/D type i.e. its sub types. This is also called as covariance.

Chrome extension: accessing localStorage in content script

Another option would be to use the chromestorage API. This allows storage of user data with optional syncing across sessions.

One downside is that it is asynchronous.

https://developer.chrome.com/extensions/storage.html

How to enable back/left swipe gesture in UINavigationController after setting leftBarButtonItem?

In Swift you can do the following code

import UIKit
extension UINavigationController: UIGestureRecognizerDelegate {

    open override func viewDidLoad() {
        super.viewDidLoad()
        interactivePopGestureRecognizer?.delegate = self
    }

    public func gestureRecognizerShouldBegin(_ gestureRecognizer: UIGestureRecognizer) -> Bool {
        return viewControllers.count > 1
    }
}

Above code helps in swift left to go back to previous controller like Facebook, Twitter.

Viewing all `git diffs` with vimdiff

For people who want to use another diff tool not listed in git, say with nvim. here is what I ended up using:

git config --global alias.d difftool -x <tool name>

In my case, I set <tool name> to nvim -d and invoke the diff command with

git d <file>

How to convert a PIL Image into a numpy array?

You're not saying how exactly putdata() is not behaving. I'm assuming you're doing

>>> pic.putdata(a)
Traceback (most recent call last):
  File "...blablabla.../PIL/Image.py", line 1185, in putdata
    self.im.putdata(data, scale, offset)
SystemError: new style getargs format but argument is not a tuple

This is because putdata expects a sequence of tuples and you're giving it a numpy array. This

>>> data = list(tuple(pixel) for pixel in pix)
>>> pic.putdata(data)

will work but it is very slow.

As of PIL 1.1.6, the "proper" way to convert between images and numpy arrays is simply

>>> pix = numpy.array(pic)

although the resulting array is in a different format than yours (3-d array or rows/columns/rgb in this case).

Then, after you make your changes to the array, you should be able to do either pic.putdata(pix) or create a new image with Image.fromarray(pix).