Programs & Examples On #Expectations

defines a set of expected and/or allowed method/constructor invocations on the mocked types/instances that have been made available to the test through mock fields and/or mock parameters (e.g., in JMockit).

.NET Core vs Mono

This question is especially actual because yesterday Microsoft officially announced .NET Core 1.0 release. Assuming that Mono implements most of the standard .NET libraries, the difference between Mono and .NET core can be seen through the difference between .NET Framework and .NET Core:

  • APIs — .NET Core contains many of the same, but fewer, APIs as the .NET Framework, and with a different factoring (assembly names are
    different; type shape differs in key cases). These differences
    currently typically require changes to port source to .NET Core. .NET Core implements the .NET Standard Library API, which will grow to
    include more of the .NET Framework BCL APIs over time.
  • Subsystems — .NET Core implements a subset of the subsystems in the .NET Framework, with the goal of a simpler implementation and
    programming model. For example, Code Access Security (CAS) is not
    supported, while reflection is supported.

If you need to launch something quickly, go with Mono because it is currently (June 2016) more mature product, but if you are building a long-term website, I would suggest .NET Core. It is officially supported by Microsoft and the difference in supported APIs will probably disappear soon, taking into account the effort that Microsoft puts in the development of .NET Core.

My goal is to use C#, LINQ, EF7, visual studio to create a website that can be ran/hosted in linux.

Linq and Entity framework are included in .NET Core, so you are safe to take a shot.

How to grep, excluding some patterns?

How about just chaining the greps?

grep -n 'loom' ~/projects/**/trunk/src/**/*.@(h|cpp) | grep -v 'gloom'

Plot 3D data in R

Adding to the solutions of others, I'd like to suggest using the plotly package for R, as this has worked well for me.

Below, I'm using the reformatted dataset suggested above, from xyz-tripplets to axis vectors x and y and a matrix z:

x <- 1:5/10
y <- 1:5
z <- x %o% y
z <- z + .2*z*runif(25) - .1*z

library(plotly)
plot_ly(x=x,y=y,z=z, type="surface")

enter image description here

The rendered surface can be rotated and scaled using the mouse. This works fairly well in RStudio.

You can also try it with the built-in volcano dataset from R:

plot_ly(z=volcano, type="surface")

enter image description here

incompatible character encodings: ASCII-8BIT and UTF-8

For prevent an error "can't modify frozen string" for encoding a varible you can use: var.dup.force_encoding(Encoding::ASCII_8BIT) or var.dup.force_encoding(Encoding::UTF_8)

org.hibernate.StaleStateException: Batch update returned unexpected row count from update [0]; actual row count: 0; expected: 1

This often happens when your SQL is bad (implicit type conversions etc.).

Turn on hibernate SQL logging by adding the following lines to your log4j properties file:

logs the SQL statements

log4j.logger.org.hibernate.SQL=debug

Logs the JDBC parameters passed to a query

log4j.logger.org.hibernate.type=trace

Before failing you will see the last SQL statement attempted in your log, copy and paste this SQL into an external SQL client and run it.

Debugging in Maven?

Just as Brian said, you can use remote debugging:

mvn exec:exec -Dexec.executable="java" -Dexec.args="-classpath %classpath -Xdebug -Xrunjdwp:transport=dt_socket,server=y,suspend=n,address=1044 com.mycompany.app.App"

Then in your eclipse, you can use remote debugging and attach the debugger to localhost:1044.

HTTP POST with URL query parameters -- good idea or not?

The REST camp have some guiding principles that we can use to standardize the way we use HTTP verbs. This is helpful when building RESTful API's as you are doing.

In a nutshell: GET should be Read Only i.e. have no effect on server state. POST is used to create a resource on the server. PUT is used to update or create a resource. DELETE is used to delete a resource.

In other words, if your API action changes the server state, REST advises us to use POST/PUT/DELETE, but not GET.

User agents usually understand that doing multiple POSTs is bad and will warn against it, because the intent of POST is to alter server state (eg. pay for goods at checkout), and you probably don't want to do that twice!

Compare to a GET which you can do an often as you like (idempotent).

What causes a java.lang.StackOverflowError

What actually causes a java.lang.StackOverflowError is typically unintentional recursion. For me it's often when I intended to call a super method for the overidden method. Such as in this case:

public class Vehicle {
    public void accelerate(float acceleration, float maxVelocity) {
        // set the acceleration
    }
}

public class SpaceShip extends Vehicle {
    @Override
    public void accelerate(float acceleration, float maxVelocity) {
        // update the flux capacitor and call super.accelerate
        // oops meant to call super.accelerate(acceleration, maxVelocity);
        // but accidentally wrote this instead. A StackOverflow is in our future.
        this.accelerate(acceleration, maxVelocity); 
    }
}

First, it's useful to know what happens behind the scenes when we call a function. The arguments and the address of where the method was called is pushed on the stack (see http://en.wikipedia.org/wiki/Stack_(abstract_data_type)#Runtime_memory_management) so that the called method can access the arguments and so that when the called method is completed, execution can continue after the call. But since we are calling this.accelerate(acceleration, maxVelocity) recursively (recursion is loosely when a method calls itself. For more info see http://en.wikipedia.org/wiki/Recursion_(computer_science)) we are in a situation known as infinite recursion and we keep piling the arguments and return address on the call stack. Since the call stack is finite in size, we eventually run out of space. The running out of space on the call stack is known as overflow. This is because we are trying to use more stack space than we have and the data literally overflows the stack. In the Java programming language, this results in the runtime exception java.lang.StackOverflow and will immediately halt the program.

The above example is somewhat simplified (although it happens to me more than I'd like to admit.) The same thing can happen in a more round about way making it a bit harder to track down. However, in general, the StackOverflow is usually pretty easy to resolve, once it occurs.

In theory, it is also possible to have a stack overflow without recursion, but in practice, it would appear to be a fairly rare event.

Is there an "exists" function for jQuery?

If you used

jQuery.fn.exists = function(){return ($(this).length > 0);}
if ($(selector).exists()) { }

you would imply that chaining was possible when it is not.

This would be better:

jQuery.exists = function(selector) {return ($(selector).length > 0);}
if ($.exists(selector)) { }

Alternatively, from the FAQ:

if ( $('#myDiv').length ) { /* Do something */ }

You could also use the following. If there are no values in the jQuery object array then getting the first item in the array would return undefined.

if ( $('#myDiv')[0] ) { /* Do something */ }

Delete last commit in bitbucket

If you are not working with others (or are happy to cause them significant annoyance), then it is possible to remove commits from bitbucket branches.

If you're trying to change a non-master branch:

git reset HEAD^               # remove the last commit from the branch history
git push origin :branch_name  # delete the branch from bitbucket
git push origin branch_name   # push the branch back up again, without the last commit

if you're trying to change the master branch

In git generally, the master branch is not special - it's just a convention. However, bitbucket and github and similar sites usually require there to be a main branch (presumably because it's easier than writing more code to handle the event that a repository has no branches - not sure). So you need to create a new branch, and make that the main branch:

# on master:
git checkout -b master_temp  
git reset HEAD^              # undo the bad commit on master_temp
git push origin master_temp  # push the new master to Bitbucket

On Bitbucket, go to the repository settings, and change the "Main branch" to master_temp (on Github, change the "Default branch").

git push origin :master     # delete the original master branch from Bitbucket
git checkout master
git reset master_temp       # reset master to master_temp (removing the bad commit)
git push origin master      # re-upload master to bitbucket

Now go to Bitbucket, and you should see the history that you want. You can now go to the settings page and change the Main branch back to master.

This process will also work with any other history changes (e.g. git filter-branch). You just have to make sure to reset to appropriate commits, before the new history split off from the old.

edit: apparently you don't need to go to all this hassle on github, as you can force-push a reset branch.

Dealing with annoyed collaborators

Next time anyone tries to pull from your repository, (if they've already pulled the bad commit), the pull will fail. They will manually have to reset to a commit before the changed history, and then pull again.

git reset HEAD^
git pull

If they have pulled the bad commit, and committed on top of it, then they will have to reset, and then git cherry-pick the good commits that they want to create, effectively re-creating the whole branch without the bad commit.

If they never pulled the bad commit, then this whole process won't affect them, and they can pull as normal.

How to restore/reset npm configuration to default values?

npm config edit

Opens the config file in an editor. Use the --global flag to edit the global config. now you can delete what ever the registry's you don't want and save file.

npm config list will display the list of available now.

Text file with 0D 0D 0A line breaks

Apple mail has also been known to make an encoding error on text and csv attachments outbound. In essence it replaces line terminators with soft line breaks on each line, which look like =0D in the encoding. If the attachment is emailed to Outlook, Outlook sees the soft line breaks, removes the = then appends real line breaks i.e. 0D0A so you get 0D0D0A (cr cr lf) at the end of each line. The encoding should be =0D= if it is a mac format file (or any other flavour of unix) or =0D0A= if it is a windows format file.

If you are emailing out from apple mail (in at least mavericks or yosemite), making the attachment not a text or csv file is an acceptable workaround e.g. compress it.

The bug also exists if you are running a windows VM under parallels and email a txt file from there using apple mail. It is the email encoding. Form previous comments here, it looks like netscape had the same issue.

Check if a string contains a string in C++

#include <algorithm>        // std::search
#include <string>
using std::search; using std::count; using std::string;

int main() {
    string mystring = "The needle in the haystack";
    string str = "needle";
    string::const_iterator it;
    it = search(mystring.begin(), mystring.end(), 
                str.begin(), str.end()) != mystring.end();

    // if string is found... returns iterator to str's first element in mystring
    // if string is not found... returns iterator to mystring.end()

if (it != mystring.end())
    // string is found
else
    // not found

return 0;
}

How to export JSON from MongoDB using Robomongo

You can use tojson to convert each record to JSON in a MongoDB shell script.

Run this script in RoboMongo:

var cursor = db.getCollection('foo').find({}, {});
while(cursor.hasNext()) {
    print(tojson(cursor.next()))
}

This prints all results as a JSON-like array.

The result is not really JSON! Some types, such as dates and object IDs, are printed as JavaScript function calls, e.g., ISODate("2016-03-03T12:15:49.996Z").

Might not be very efficient for large result sets, but you can limit the query. Alternatively, you can use mongoexport.

React JS - Uncaught TypeError: this.props.data.map is not a function

I had the same problem. The solution was to change the useState initial state value from string to array. In App.js, previous useState was

const [favoriteFilms, setFavoriteFilms] = useState('');

I changed it to

const [favoriteFilms, setFavoriteFilms] = useState([]);

and the component that uses those values stopped throwing error with .map function.

How can I fill a column with random numbers in SQL? I get the same value in every row

If you are on SQL Server 2008 you can also use

 CRYPT_GEN_RANDOM(2) % 10000

Which seems somewhat simpler (it is also evaluated once per row as newid is - shown below)

DECLARE @foo TABLE (col1 FLOAT)

INSERT INTO @foo SELECT 1 UNION SELECT 2

UPDATE @foo
SET col1 =  CRYPT_GEN_RANDOM(2) % 10000

SELECT *  FROM @foo

Returns (2 random probably different numbers)

col1
----------------------
9693
8573

Mulling the unexplained downvote the only legitimate reason I can think of is that because the random number generated is between 0-65535 which is not evenly divisible by 10,000 some numbers will be slightly over represented. A way around this would be to wrap it in a scalar UDF that throws away any number over 60,000 and calls itself recursively to get a replacement number.

CREATE FUNCTION dbo.RandomNumber()
RETURNS INT
AS
  BEGIN
      DECLARE @Result INT

      SET @Result = CRYPT_GEN_RANDOM(2)

      RETURN CASE
               WHEN @Result < 60000
                     OR @@NESTLEVEL = 32 THEN @Result % 10000
               ELSE dbo.RandomNumber()
             END
  END  

Positioning the colorbar

The best way to get good control over the colorbar position is to give it its own axis. Like so:

# What I imagine your plotting looks like so far
fig = plt.figure()
ax1 = fig.add_subplot(111)
ax1.plot(your_data)

# Now adding the colorbar
cbaxes = fig.add_axes([0.8, 0.1, 0.03, 0.8]) 
cb = plt.colorbar(ax1, cax = cbaxes)  

The numbers in the square brackets of add_axes refer to [left, bottom, width, height], where the coordinates are just fractions that go from 0 to 1 of the plotting area.

HTTP Headers for File Downloads

You can try this force-download script. Even if you don't use it, it'll probably point you in the right direction:

<?php

$filename = $_GET['file'];

// required for IE, otherwise Content-disposition is ignored
if(ini_get('zlib.output_compression'))
  ini_set('zlib.output_compression', 'Off');

// addition by Jorg Weske
$file_extension = strtolower(substr(strrchr($filename,"."),1));

if( $filename == "" ) 
{
  echo "<html><title>eLouai's Download Script</title><body>ERROR: download file NOT SPECIFIED. USE force-download.php?file=filepath</body></html>";
  exit;
} elseif ( ! file_exists( $filename ) ) 
{
  echo "<html><title>eLouai's Download Script</title><body>ERROR: File not found. USE force-download.php?file=filepath</body></html>";
  exit;
};
switch( $file_extension )
{
  case "pdf": $ctype="application/pdf"; break;
  case "exe": $ctype="application/octet-stream"; break;
  case "zip": $ctype="application/zip"; break;
  case "doc": $ctype="application/msword"; break;
  case "xls": $ctype="application/vnd.ms-excel"; break;
  case "ppt": $ctype="application/vnd.ms-powerpoint"; break;
  case "gif": $ctype="image/gif"; break;
  case "png": $ctype="image/png"; break;
  case "jpeg":
  case "jpg": $ctype="image/jpg"; break;
  default: $ctype="application/octet-stream";
}
header("Pragma: public"); // required
header("Expires: 0");
header("Cache-Control: must-revalidate, post-check=0, pre-check=0");
header("Cache-Control: private",false); // required for certain browsers 
header("Content-Type: $ctype");
// change, added quotes to allow spaces in filenames, by Rajkumar Singh
header("Content-Disposition: attachment; filename=\"".basename($filename)."\";" );
header("Content-Transfer-Encoding: binary");
header("Content-Length: ".filesize($filename));
readfile("$filename");
exit();

mysql command for showing current configuration variables

What you are looking for is this:

SHOW VARIABLES;  

You can modify it further like any query:

SHOW VARIABLES LIKE '%max%';  

Use a LIKE statement on SQL Server XML Datatype

This is what I am going to use based on marc_s answer:

SELECT 
SUBSTRING(DATA.value('(/PAGECONTENT/TEXT)[1]', 'VARCHAR(100)'),PATINDEX('%NORTH%',DATA.value('(/PAGECONTENT/TEXT)[1]', 'VARCHAR(100)')) - 20,999)

FROM WEBPAGECONTENT 
WHERE COALESCE(PATINDEX('%NORTH%',DATA.value('(/PAGECONTENT/TEXT)[1]', 'VARCHAR(100)')),0) > 0

Return a substring on the search where the search criteria exists

how to get all child list from Firebase android

Saving and Retriving data to - from Firebase ( deprecated ver 2.4.2 )

Firebase fb_parent = new Firebase("YOUR-FIREBASE-URL/");
Firebase fb_to_read = fb_parent.child("students/names");
Firebase fb_put_child = fb_to_read.push(); // REMEMBER THIS FOR PUSH METHOD

//INSERT DATA TO STUDENT - NAMES  I Use Push Method
fb_put_child.setValue("Zacharia"); //OR fb_put_child.setValue(YOUR MODEL) 
fb_put_child.setValue("Joseph"); //OR fb_put_child.setValue(YOUR MODEL) 
fb_put_child.setValue("bla blaaa"); //OR fb_put_child.setValue(YOUR MODEL) 

//GET DATA FROM FIREBASE INTO ARRAYLIST
fb_to_read.addValuesEventListener....{
    public void onDataChange(DataSnapshot result){
        List<String> lst = new ArrayList<String>(); // Result will be holded Here
        for(DataSnapshot dsp : result.getChildren()){
            lst.add(String.valueOf(dsp.getKey())); //add result into array list
        }
        //NOW YOU HAVE ARRAYLIST WHICH HOLD RESULTS




for(String data:lst){ 
         Toast.make(context,data,Toast.LONG_LENGTH).show; 
       }
    }
}

Decimal precision and scale in EF Code First

If you want to set the precision for all decimals in EF6 you could replace the default DecimalPropertyConvention convention used in the DbModelBuilder:

protected override void OnModelCreating(DbModelBuilder modelBuilder)
{
    modelBuilder.Conventions.Remove<DecimalPropertyConvention>();
    modelBuilder.Conventions.Add(new DecimalPropertyConvention(38, 18));
}

The default DecimalPropertyConvention in EF6 maps decimal properties to decimal(18,2) columns.

If you only want individual properties to have a specified precision then you can set the precision for the entity's property on the DbModelBuilder:

protected override void OnModelCreating(DbModelBuilder modelBuilder)
{
    modelBuilder.Entity<MyEntity>().Property(e => e.Value).HasPrecision(38, 18);
}

Or, add an EntityTypeConfiguration<> for the entity which specifies the precision:

protected override void OnModelCreating(DbModelBuilder modelBuilder)
{
    modelBuilder.Configurations.Add(new MyEntityConfiguration());
}

internal class MyEntityConfiguration : EntityTypeConfiguration<MyEntity>
{
    internal MyEntityConfiguration()
    {
        this.Property(e => e.Value).HasPrecision(38, 18);
    }
}

cmake - find_library - custom library location

There is no way to automatically set CMAKE_PREFIX_PATH in a way you want. I see following ways to solve this problem:

  1. Put all libraries files in the same dir. That is, include/ would contain headers for all libs, lib/ - binaries, etc. FYI, this is common layout for most UNIX-like systems.

  2. Set global environment variable CMAKE_PREFIX_PATH to D:/develop/cmake/libs/libA;D:/develop/cmake/libs/libB;.... When you run CMake, it would aautomatically pick up this env var and populate it's own CMAKE_PREFIX_PATH.

  3. Write a wrapper .bat script, which would call cmake command with -D CMAKE_PREFIX_PATH=... argument.

Launch an app on OS X with command line

I would recommend the technique that MathieuK offers. In my case, I needed to try it with Chromium:

> Chromium.app/Contents/MacOS/Chromium --enable-remote-fonts

I realize this doesn't solve the OP's problem, but hopefully it saves someone else's time. :)

PANIC: Broken AVD system path. Check your ANDROID_SDK_ROOT value

I had the same problem. I deleted the image emulator on the .android/avd folder and after I installed the lib32stdc++6:

sudo apt-get install lib32stdc++6

So, it works! Magic?

How to check if user input is not an int value

Simply throw Exception if input is invalid

Scanner sc=new Scanner(System.in);
try
{
  System.out.println("Please input an integer");
  //nextInt will throw InputMismatchException
  //if the next token does not match the Integer
  //regular expression, or is out of range
  int usrInput=sc.nextInt();
}
catch(InputMismatchException exception)
{
  //Print "This is not an integer"
  //when user put other than integer
  System.out.println("This is not an integer");
}

Find records with a date field in the last 24 hours

To get records from the last 24 hours:

SELECT * from [table_name] WHERE date > (NOW() - INTERVAL 24 HOUR)

Access files in /var/mobile/Containers/Data/Application without jailbreaking iPhone

If this is your app, if you connect the device to your computer, you can use the "Devices" option on Xcode's "Window" menu and then download the app's data container to your computer. Just select your app from the list of installed apps, and click on the "gear" icon and choose "Download Container".

enter image description here

Once you've downloaded it, right click on the file in the Finder and choose "Show Package Contents".

What's the difference between “mod” and “remainder”?

In C and C++ and many languages, % is the remainder NOT the modulus operator.

For example in the operation -21 / 4 the integer part is -5 and the decimal part is -.25. The remainder is the fractional part times the divisor, so our remainder is -1. JavaScript uses the remainder operator and confirms this

_x000D_
_x000D_
console.log(-21 % 4 == -1);
_x000D_
_x000D_
_x000D_

The modulus operator is like you had a "clock". Imagine a circle with the values 0, 1, 2, and 3 at the 12 o'clock, 3 o'clock, 6 o'clock, and 9 o'clock positions respectively. Stepping quotient times around the clock clock-wise lands us on the result of our modulus operation, or, in our example with a negative quotient, counter-clockwise, yielding 3.

Note: Modulus is always the same sign as the divisor and remainder the same sign as the quotient. Adding the divisor and the remainder when at least one is negative yields the modulus.

What is setContentView(R.layout.main)?

Set the activity content from a layout resource. The resource will be inflated, adding all top-level views to the activity.

  • Activity is basically a empty window
  • SetContentView is used to fill the window with the UI provided from layout file incase of setContentView(R.layout.somae_file).
  • Here layoutfile is inflated to view and added to the Activity context(Window).

NumPy ValueError: The truth value of an array with more than one element is ambiguous. Use a.any() or a.all()

try this=> numpy.array(yourvariable) followed by the command to compare, whatever you wish to.

ojdbc14.jar vs. ojdbc6.jar

The "14" and "6" in those driver names refer to the JVM they were written for. If you're still using JDK 1.4 I'd say you have a serious problem and need to upgrade. JDK 1.4 is long past its useful support life. It didn't even have generics! JDK 6 u21 is the current production standard from Oracle/Sun. I'd recommend switching to it if you haven't already.

Could not find folder 'tools' inside SDK

I faced similar issue when the SDK tools installation was failed during the initial setup. To resolution is to download SDK tools from Android Developer Site

  • Expand "USE AN EXISTING IDE" section and download standalone SDK tools
  • Choose your destination as (%HOMEPATH%\android-sdks)
  • Now start Android-SDKs folder and run SDK manager

How to parse a string into a nullable int

The following should work for any struct type. It is based off code by Matt Manela from MSDN forums. As Murph points out the exception handling could be expensive compared to using the Types dedicated TryParse method.

        public static bool TryParseStruct<T>(this string value, out Nullable<T> result)
            where T: struct 
        {
            if (string.IsNullOrEmpty(value))
            {
                result = new Nullable<T>();

                return true;
            }

            result = default(T);
            try
            {
                IConvertible convertibleString = (IConvertible)value;
                result = new Nullable<T>((T)convertibleString.ToType(typeof(T), System.Globalization.CultureInfo.CurrentCulture));
            }
            catch(InvalidCastException)
            {
                return false;
            }
            catch (FormatException)
            {
                return false;
            }

           return true;
        }

These were the basic test cases I used.

        string parseOne = "1";
        int? resultOne;
        bool successOne = parseOne.TryParseStruct<int>(out resultOne);
        Assert.IsTrue(successOne);
        Assert.AreEqual(1, resultOne);

        string parseEmpty = string.Empty;
        int? resultEmpty;
        bool successEmpty = parseEmpty.TryParseStruct<int>(out resultEmpty);
        Assert.IsTrue(successEmpty);
        Assert.IsFalse(resultEmpty.HasValue);

        string parseNull = null;
        int? resultNull;
        bool successNull = parseNull.TryParseStruct<int>(out resultNull);
        Assert.IsTrue(successNull);
        Assert.IsFalse(resultNull.HasValue);

        string parseInvalid = "FooBar";
        int? resultInvalid;
        bool successInvalid = parseInvalid.TryParseStruct<int>(out resultInvalid);
        Assert.IsFalse(successInvalid);

Command to get time in milliseconds

date +%s%N returns the number of seconds + current nanoseconds.

Therefore, echo $(($(date +%s%N)/1000000)) is what you need.

Example:

$ echo $(($(date +%s%N)/1000000))
1535546718115

date +%s returns the number of seconds since the epoch, if that's useful.

How to print from Flask @app.route to python console

It seems like you have it worked out, but for others looking for this answer, an easy way to do this is by printing to stderr. You can do that like this:

from __future__ import print_function # In python 2.7
import sys

@app.route('/button/')
def button_clicked():
    print('Hello world!', file=sys.stderr)
    return redirect('/')

Flask will display things printed to stderr in the console. For other ways of printing to stderr, see this stackoverflow post

POST JSON to API using Rails and HTTParty

The :query_string_normalizer option is also available, which will override the default normalizer HashConversions.to_params(query)

query_string_normalizer: ->(query){query.to_json}

How to recover closed output window in netbeans?

in Netbeans 7.4 try Window -> Output OR Ctrl + 4

SQL Server Express CREATE DATABASE permission denied in database 'master'

If you got the same error in Sql server 2008 management studio than below link will resolve this error after so much effort i found this link: http://social.msdn.microsoft.com/Forums/en-US/sqlexpress/thread/76fc84f9-437c-4e71-ba3d-3c9ae794a7c4/

How to find the mysql data directory from command line in windows

Use bellow command from CLI interface

[root@localhost~]# mysqladmin variables -p<password> | grep datadir

How to read a CSV file into a .NET Datatable

this is the code i use it but your apps must run with net version 3.5

private void txtRead_Click(object sender, EventArgs e)
        {
           // var filename = @"d:\shiptest.txt";

            openFileDialog1.InitialDirectory = "d:\\";
            openFileDialog1.Filter = "txt files (*.txt)|*.txt|All files (*.*)|*.*";
            DialogResult result = openFileDialog1.ShowDialog();
            if (result == DialogResult.OK)
            {
                if (openFileDialog1.FileName != "")
                {
                    var reader = ReadAsLines(openFileDialog1.FileName);

                    var data = new DataTable();

                    //this assume the first record is filled with the column names
                    var headers = reader.First().Split(',');
                    foreach (var header in headers)
                    {
                        data.Columns.Add(header);
                    }

                    var records = reader.Skip(1);
                    foreach (var record in records)
                    {
                        data.Rows.Add(record.Split(','));
                    }

                    dgList.DataSource = data;
                }
            }
        }

        static IEnumerable<string> ReadAsLines(string filename)
        {
            using (StreamReader reader = new StreamReader(filename))
                while (!reader.EndOfStream)
                    yield return reader.ReadLine();
        }

What does -XX:MaxPermSize do?

-XX:PermSize -XX:MaxPermSize are used to set size for Permanent Generation.

Permanent Generation: The Permanent Generation is where class files are kept. These are the result of compiled classes and JSP pages. If this space is full, it triggers a Full Garbage Collection. If the Full Garbage Collection cannot clean out old unreferenced classes and there is no room left to expand the Permanent Space, an Out-of- Memory error (OOME) is thrown and the JVM will crash.

Changing the default title of confirm() in JavaScript?

YES YOU CAN do it!! It's a little tricky way ; ) (it almost works on ios)

var iframe = document.createElement("IFRAME");
iframe.setAttribute("src", 'data:text/plain,');
document.documentElement.appendChild(iframe);
if(window.frames[0].window.confirm("Are you sure?")){
    // what to do if answer "YES"
}else{
    // what to do if answer "NO"
}

Enjoy it!

How can I save application settings in a Windows Forms application?

If you work with Visual Studio then it is pretty easy to get persistable settings. Right click on the project in Solution Explorer and choose Properties. Select the Settings tab and click on the hyperlink if settings doesn't exist.

Use the Settings tab to create application settings. Visual Studio creates the files Settings.settings and Settings.Designer.settings that contain the singleton class Settings inherited from ApplicationSettingsBase. You can access this class from your code to read/write application settings:

Properties.Settings.Default["SomeProperty"] = "Some Value";
Properties.Settings.Default.Save(); // Saves settings in application configuration file

This technique is applicable both for console, Windows Forms, and other project types.

Note that you need to set the scope property of your settings. If you select Application scope then Settings.Default.<your property> will be read-only.

Reference: How To: Write User Settings at Run Time with C# - Microsoft Docs

Bash script error [: !=: unary operator expected

Quotes!

if [ "$1" != -v ]; then

Otherwise, when $1 is completely empty, your test becomes:

[ != -v ]

instead of

[ "" != -v ]

...and != is not a unary operator (that is, one capable of taking only a single argument).

Difference between File.separator and slash in paths

OK let's inspect some code.
File.java lines 428 to 435 in File.<init>:

String p = uri.getPath();
if (p.equals(""))
    throw new IllegalArgumentException("URI path component is empty");

// Okay, now initialize
p = fs.fromURIPath(p);
if (File.separatorChar != '/')
p = p.replace('/', File.separatorChar);

And let's read fs/*(FileSystem)*/.fromURIPath() docs:

java.io.FileSystem
public abstract String fromURIPath(String path)
Post-process the given URI path string if necessary. This is used on win32, e.g., to transform "/c:/foo" into "c:/foo". The path string still has slash separators; code in the File class will translate them after this method returns.

This means FileSystem.fromURIPath() does post processing on URI path only in Windows, and because in the next line:

p = p.replace('/', File.separatorChar);

It replaces each '/' with system dependent seperatorChar, you can always be sure that '/' is safe in every OS.

Tab key == 4 spaces and auto-indent after curly braces in Vim

edit your ~/.vimrc

$ vim ~/.vimrc

add following lines :

set tabstop=4
set shiftwidth=4
set softtabstop=4
set expandtab

A 'for' loop to iterate over an enum in Java

Java8

Stream.of(Direction.values()).forEach(System.out::println);

from Java5+

for ( Direction d: Direction.values()){
 System.out.println(d);
}

Sending Windows key using SendKeys

SetForegroundWindow( /* window to gain focus */ );
SendKeys.SendWait("^{ESC}"); // ^{ESC} is code for ctrl + esc which mimics the windows key.

How to display custom view in ActionBar?

There is an example in the launcher app of Android (that I've made a library out of it, here), inside the class that handles wallpapers-picking ("WallpaperPickerActivity") .

The example shows that you need to set a customized theme for this to work. Sadly, this worked for me only using the normal framework, and not the one of the support library.

Here're the themes:

styles.xml

 <style name="Theme.WallpaperPicker" parent="Theme.WallpaperCropper">
    <item name="android:windowBackground">@android:color/transparent</item>
    <item name="android:colorBackgroundCacheHint">@null</item>
    <item name="android:windowShowWallpaper">true</item>
  </style>

  <style name="Theme.WallpaperCropper" parent="@android:style/Theme.DeviceDefault">
    <item name="android:actionBarStyle">@style/WallpaperCropperActionBar</item>
    <item name="android:windowFullscreen">true</item>
    <item name="android:windowActionBarOverlay">true</item>
  </style>

  <style name="WallpaperCropperActionBar" parent="@android:style/Widget.DeviceDefault.ActionBar">
    <item name="android:displayOptions">showCustom</item>
    <item name="android:background">#88000000</item>
  </style>

value-v19/styles.xml

 <style name="Theme.WallpaperCropper" parent="@android:style/Theme.DeviceDefault">
    <item name="android:actionBarStyle">@style/WallpaperCropperActionBar</item>
    <item name="android:windowFullscreen">true</item>
    <item name="android:windowActionBarOverlay">true</item>
    <item name="android:windowTranslucentNavigation">true</item>
  </style>

  <style name="Theme" parent="@android:style/Theme.DeviceDefault.Wallpaper.NoTitleBar">
    <item name="android:windowTranslucentStatus">true</item>
    <item name="android:windowTranslucentNavigation">true</item>
  </style>

EDIT: there is a better way to do it, which works on the support library too. Just add this line of code instead of what I've written above:

getSupportActionBar().setDisplayShowCustomEnabled(true);

How to bind Events on Ajax loaded Content?

if your question is "how to bind events on ajax loaded content" you can do like this :

$("img.lazy").lazyload({
    effect : "fadeIn",
    event: "scrollstop",
    skip_invisible : true
}).removeClass('lazy');

// lazy load to DOMNodeInserted event
$(document).bind('DOMNodeInserted', function(e) {
    $("img.lazy").lazyload({
        effect : "fadeIn",
        event: "scrollstop",
        skip_invisible : true
    }).removeClass('lazy');
});

so you don't need to place your configuration to every you ajax code

Jquery to open Bootstrap v3 modal of remote url

From Bootstrap's docs about the remote option;

This option is deprecated since v3.3.0 and has been removed in v4. We recommend instead using client-side templating or a data binding framework, or calling jQuery.load yourself.

If a remote URL is provided, content will be loaded one time via jQuery's load method and injected into the .modal-content div. If you're using the data-api, you may alternatively use the href attribute to specify the remote source. An example of this is shown below:

<a data-toggle="modal" href="remote.html" data-target="#modal">Click me</a>

That's the .modal-content div, not .modal-body. If you want to put content inside .modal-body then you need to do that with custom javascript.

So I would call jQuery.load programmatically, meaning you can keep the functionality of the dismiss and/or other buttons as required.

To do this you could use a data tag with the URL from the button that opens the modal, and use the show.bs.modal event to load content into the .modal-body div.

HTML Link/Button

<a href="#" data-toggle="modal" data-load-url="remote.html" data-target="#myModal">Click me</a>

jQuery

$('#myModal').on('show.bs.modal', function (e) {
    var loadurl = $(e.relatedTarget).data('load-url');
    $(this).find('.modal-body').load(loadurl);
});

How to check in Javascript if one element is contained within another

You can use the contains method

var result = parent.contains(child);

or you can try to use compareDocumentPosition()

var result = nodeA.compareDocumentPosition(nodeB);

The last one is more powerful: it return a bitmask as result.

Android Pop-up message

You can use Dialog to create this easily

create a Dialog instance using the context

Dialog dialog = new Dialog(contex);

You can design your layout as you like.

You can add this layout to your dialog by dialog.setContentView(R.layout.popupview);//popup view is the layout you created

then you can access its content (textviews, etc.) by using findViewById method

TextView txt = (TextView)dialog.findViewById(R.id.textbox);

you can add any text here. the text can be stored in the String.xml file in res\values.

txt.setText(getString(R.string.message));

then finally show the pop up menu

dialog.show();

more information http://developer.android.com/guide/topics/ui/dialogs.html

http://developer.android.com/reference/android/app/Dialog.html

What's the difference between Instant and LocalDateTime?

One main difference is the Local part of LocalDateTime. If you live in Germany and create a LocalDateTime instance and someone else lives in USA and creates another instance at the very same moment (provided the clocks are properly set) - the value of those objects would actually be different. This does not apply to Instant, which is calculated independently from time zone.

LocalDateTime stores date and time without timezone, but it's initial value is timezone dependent. Instant's is not.

Moreover, LocalDateTime provides methods for manipulating date components like days, hours, months. An Instant does not.

apart from the nanosecond precision advantage of Instant and the time-zone part of LocalDateTime

Both classes have the same precision. LocalDateTime does not store timezone. Read javadocs thoroughly, because you may make a big mistake with such invalid assumptions: Instant and LocalDateTime.

Split a string into an array of strings based on a delimiter

For delphi 2010, you need to create your own split function.

function Split(const Texto, Delimitador: string): TStringArray;
var
  i: integer;
  Len: integer;
  PosStart: integer;
  PosDel: integer;
  TempText:string;
begin
  i := 0;
  SetLength(Result, 1);
  Len := Length(Delimitador);
  PosStart := 1;
  PosDel := Pos(Delimitador, Texto);
  TempText:=  Texto;
  while PosDel > 0 do
    begin
      Result[i] := Copy(TempText, PosStart, PosDel - PosStart);
      PosStart := PosDel + Len;
      TempText:=Copy(TempText, PosStart, Length(TempText));
      PosDel := Pos(Delimitador, TempText);
      PosStart := 1;
      inc(i);
      SetLength(Result, i + 1);
    end;
  Result[i] := Copy(TempText, PosStart, Length(TempText));
end;

You can refer to it as such

type
  TStringArray = array of string;
var Temp2:TStringArray;
Temp1="hello:world";
Temp2=Split(Temp1,':')

determine DB2 text string length

This will grab records with strings (in the fieldName column) that are 10 characters long:

 select * from table where length(fieldName)=10

How do I include a pipe | in my linux find -exec command?

the solution is easy: execute via sh

... -exec sh -c "zcat {} | agrep -dEOE 'grep' " \;

Can constructors throw exceptions in Java?

Absolutely.

If the constructor doesn't receive valid input, or can't construct the object in a valid manner, it has no other option but to throw an exception and alert its caller.

SQL select join: is it possible to prefix all columns as 'prefix.*'?

This question is very useful in practice. It's only necessary to list every explicit columns in software programming, where you pay particular careful to deal with all conditions.

Imagine when debugging, or, try to use DBMS as daily office tool, instead of something alterable implementation of specific programmer's abstract underlying infrastructure, we need to code a lot of SQLs. The scenario can be found everywhere, like database conversion, migration, administration, etc. Most of these SQLs will be executed only once and never be used again, give the every column names is just waste of time. And don't forget the invention of SQL isn't only for the programmers use.

Usually I will create a utility view with column names prefixed, here is the function in pl/pgsql, it's not easy but you can convert it to other procedure languages.

-- Create alias-view for specific table.

create or replace function mkaview(schema varchar, tab varchar, prefix varchar)
    returns table(orig varchar, alias varchar) as $$
declare
    qtab varchar;
    qview varchar;
    qcol varchar;
    qacol varchar;
    v record;
    sql varchar;
    len int;
begin
    qtab := '"' || schema || '"."' || tab || '"';
    qview := '"' || schema || '"."av' || prefix || tab || '"';
    sql := 'create view ' || qview || ' as select';

    for v in select * from information_schema.columns
            where table_schema = schema and table_name = tab
    loop
        qcol := '"' || v.column_name || '"';
        qacol := '"' || prefix || v.column_name || '"';

        sql := sql || ' ' || qcol || ' as ' || qacol;
        sql := sql || ', ';

        return query select qcol::varchar, qacol::varchar;
    end loop;

    len := length(sql);
    sql := left(sql, len - 2); -- trim the trailing ', '.
    sql := sql || ' from ' || qtab;

    raise info 'Execute SQL: %', sql;
    execute sql;
end
$$ language plpgsql;

Examples:

-- This will create a view "avp_person" with "p_" prefix to all column names.
select * from mkaview('public', 'person', 'p_');

select * from avp_person;

Calculate correlation for more than two variables?

Use the same function (cor) on a data frame, e.g.:

> cor(VADeaths)
             Rural Male Rural Female Urban Male Urban Female
Rural Male    1.0000000    0.9979869  0.9841907    0.9934646
Rural Female  0.9979869    1.0000000  0.9739053    0.9867310
Urban Male    0.9841907    0.9739053  1.0000000    0.9918262
Urban Female  0.9934646    0.9867310  0.9918262    1.0000000

Or, on a data frame also holding discrete variables, (also sometimes referred to as factors), try something like the following:

> cor(mtcars[,unlist(lapply(mtcars, is.numeric))])
            mpg        cyl       disp         hp        drat         wt        qsec         vs          am       gear        carb
mpg   1.0000000 -0.8521620 -0.8475514 -0.7761684  0.68117191 -0.8676594  0.41868403  0.6640389  0.59983243  0.4802848 -0.55092507
cyl  -0.8521620  1.0000000  0.9020329  0.8324475 -0.69993811  0.7824958 -0.59124207 -0.8108118 -0.52260705 -0.4926866  0.52698829
disp -0.8475514  0.9020329  1.0000000  0.7909486 -0.71021393  0.8879799 -0.43369788 -0.7104159 -0.59122704 -0.5555692  0.39497686
hp   -0.7761684  0.8324475  0.7909486  1.0000000 -0.44875912  0.6587479 -0.70822339 -0.7230967 -0.24320426 -0.1257043  0.74981247
drat  0.6811719 -0.6999381 -0.7102139 -0.4487591  1.00000000 -0.7124406  0.09120476  0.4402785  0.71271113  0.6996101 -0.09078980
wt   -0.8676594  0.7824958  0.8879799  0.6587479 -0.71244065  1.0000000 -0.17471588 -0.5549157 -0.69249526 -0.5832870  0.42760594
qsec  0.4186840 -0.5912421 -0.4336979 -0.7082234  0.09120476 -0.1747159  1.00000000  0.7445354 -0.22986086 -0.2126822 -0.65624923
vs    0.6640389 -0.8108118 -0.7104159 -0.7230967  0.44027846 -0.5549157  0.74453544  1.0000000  0.16834512  0.2060233 -0.56960714
am    0.5998324 -0.5226070 -0.5912270 -0.2432043  0.71271113 -0.6924953 -0.22986086  0.1683451  1.00000000  0.7940588  0.05753435
gear  0.4802848 -0.4926866 -0.5555692 -0.1257043  0.69961013 -0.5832870 -0.21268223  0.2060233  0.79405876  1.0000000  0.27407284
carb -0.5509251  0.5269883  0.3949769  0.7498125 -0.09078980  0.4276059 -0.65624923 -0.5696071  0.05753435  0.2740728  1.00000000

How to do this in Laravel, subquery where in

Laravel 4.2 and beyond, may use try relationship querying:-

Products::whereHas('product_category', function($query) {
$query->whereIn('category_id', ['223', '15']);
});

public function product_category() {
return $this->hasMany('product_category', 'product_id');
}

Deleting Objects in JavaScript

I stumbled across this article in my search for this same answer. What I ended up doing is just popping out obj.pop() all the stored values/objects in my object so I could reuse the object. Not sure if this is bad practice or not. This technique came in handy for me testing my code in Chrome Dev tools or FireFox Web Console.

Pure css close button

I become frustrated trying to implement something that looked consistent in all browsers and went with an svg button which can be styled with css.

html

<svg>
    <circle cx="12" cy="12" r="11" stroke="black" stroke-width="2" fill="white" />
    <path stroke="black" stroke-width="4" fill="none" d="M6.25,6.25,17.75,17.75" />
    <path stroke="black" stroke-width="4" fill="none" d="M6.25,17.75,17.75,6.25" />
</svg>

css

svg {
    cursor: pointer;
    height: 24px;
    width: 24px;
}
svg > circle {
    stroke: black;
    fill: white;
}
svg > path {
    stroke: black;
}
svg:hover > circle {
    fill: red;
}
svg:hover > path {
    stroke: white;
}

http://jsfiddle.net/purves/5exav2m7/

Save and retrieve image (binary) from SQL Server using Entity Framework 6

Convert the image to a byte[] and store that in the database.


Add this column to your model:

public byte[] Content { get; set; }

Then convert your image to a byte array and store that like you would any other data:

public byte[] ImageToByteArray(System.Drawing.Image imageIn)
{
    using(var ms = new MemoryStream())
    {
        imageIn.Save(ms, System.Drawing.Imaging.ImageFormat.Gif);

        return ms.ToArray();
    }
}

public Image ByteArrayToImage(byte[] byteArrayIn)
{
     using(var ms = new MemoryStream(byteArrayIn))
     {
         var returnImage = Image.FromStream(ms);

         return returnImage;
     }
}

Source: Fastest way to convert Image to Byte array

var image = new ImageEntity()
{
   Content = ImageToByteArray(image)
};

_context.Images.Add(image);
_context.SaveChanges();

When you want to get the image back, get the byte array from the database and use the ByteArrayToImage and do what you wish with the Image

This stops working when the byte[] gets to big. It will work for files under 100Mb

Module AppRegistry is not registered callable module (calling runApplication)

Need to replace

.setJSMainModulePath("index") with .setJSMainModulePath("index.android")

How to group by week in MySQL?

Just ad this in the select :

DATE_FORMAT($yourDate, \'%X %V\') as week

And

group_by(week);

How to config Tomcat to serve images from an external folder outside webapps?

Instead of configuring Tomcat to redirect requests, use Apache as a frontend with the Apache Tomcat connector so that Apache is only serving static content, while asking tomcat for dynamic content.

Using the JKmount directive (or others) you could specify exactly which requests are sent to Tomcat.

Requests for static content, such as images, would be served directly by Apache, using a standard virtual host configuration, while other requests, defined in the JKMount directive will be sent to Tomcat workers.

I think this implementation would give you the most flexibility and control on the overall application.

Catching exceptions from Guzzle

In my case I was throwing Exception on a namespaced file, so php tried to catch My\Namespace\Exception therefore not catching any exceptions at all.

Worth checking if catch (Exception $e) is finding the right Exception class.

Just try catch (\Exception $e) (with that \ there) and see if it works.

Get the (last part of) current directory name in C#

You can also use the Uri class.

new Uri("file:///Users/smcho/filegen_from_directory/AIRPassthrough").Segments.Last()

You may prefer to use this class if you want to get some other segment, or if you want to do the same thing with a web address.

Documentation for using JavaScript code inside a PDF file

Here you can find "Adobe Acrobat Forms JavaScript Object Specification Version 4.0"

Revised: January 27, 1999

It’s very old, but it is still useful.

Is there a format code shortcut for Visual Studio?

To align the text in the proper format -

  • Ctrl + K + D for front end pages like .aspx or .cshtml

  • Ctrl + K + F for a .cs page

But observe to press all buttons in sequence...

Differences between git pull origin master & git pull origin/master

git pull = git fetch + git merge origin/branch

git pull and git pull origin branch only differ in that the latter will only "update" origin/branch and not all origin/* as git pull does.

git pull origin/branch will just not work because it's trying to do a git fetch origin/branch which is invalid.

Question related: git fetch + git merge origin/master vs git pull origin/master

ansible : how to pass multiple commands

Here is worker like this. \o/

- name: "Exec items"
  shell: "{{ item }}"
  with_items:
    - echo "hello"
    - echo "hello2"

eslint: error Parsing error: The keyword 'const' is reserved

In my case, it was unable to find the .eslintrc file so I copied from node_modules/.bin to root.

Getting Gradle dependencies in IntelliJ IDEA using Gradle build

After adding dependencies open "Gradle" ('View'->Tool Windows->Gradle) tab and hit "refresh"

example of adding (compile 'io.reactivex:rxjava:1.1.0'):

hit refresh

If Idea still can not resolve dependency, hence it is possibly the dependency is not in mavenCentral() repository and you need add repository where this dependency located into repositories{}

How to use && in EL boolean expressions in Facelets?

Facelets is a XML based view technology. The & is a special character in XML representing the start of an entity like &amp; which ends with the ; character. You'd need to either escape it, which is ugly:

rendered="#{beanA.prompt == true &amp;&amp; beanB.currentBase != null}"

or to use the and keyword instead, which is preferred as to readability and maintainability:

rendered="#{beanA.prompt == true and beanB.currentBase != null}"

See also:


Unrelated to the concrete problem, comparing booleans with booleans makes little sense when the expression expects a boolean outcome already. I'd get rid of == true:

rendered="#{beanA.prompt and beanB.currentBase != null}"

Convert Json Array to normal Java list

How about using java.util.Arrays?

List<String> list = Arrays.asList((String[])jsonArray.toArray())

Invoke or BeginInvoke cannot be called on a control until the window handle has been created

I had this problem with this kind of simple form:

public partial class MyForm : Form
{
    public MyForm()
    {
        Load += new EventHandler(Form1_Load);
    }

    private void Form1_Load(Object sender, EventArgs e)
    {
        InitializeComponent();
    }

    internal void UpdateLabel(string s)
    {
        Invoke(new Action(() => { label1.Text = s; }));
    }
}

Then for n other async threads I was using new MyForm().UpdateLabel(text) to try and call the UI thread, but the constructor gives no handle to the UI thread instance, so other threads get other instance handles, which are either Object reference not set to an instance of an object or Invoke or BeginInvoke cannot be called on a control until the window handle has been created. To solve this I used a static object to hold the UI handle:

public partial class MyForm : Form
{
    private static MyForm _mf;        

    public MyForm()
    {
        Load += new EventHandler(Form1_Load);
    }

    private void Form1_Load(Object sender, EventArgs e)
    {
        InitializeComponent();
        _mf = this;
    }

    internal void UpdateLabel(string s)
    {
        _mf.Invoke((MethodInvoker) delegate { _mf.label1.Text = s; });
    }
}

I guess it's working fine, so far...

How to reload/refresh jQuery dataTable?

Allan Jardine’s DataTables is a very powerful and slick jQuery plugin for displaying tabular data. It has many features and can do most of what you might want. One thing that’s curiously difficult though, is how to refresh the contents in a simple way, so I for my own reference, and possibly for the benefit of others as well, here’s a complete example of one way if doing this:

HTML

<table id="HelpdeskOverview">
  <thead>
    <tr>
      <th>Ärende</th>
      <th>Rapporterad</th>
      <th>Syst/Utr/Appl</th>
      <th>Prio</th>
      <th>Rubrik</th>
      <th>Status</th>
      <th>Ägare</th>
    </tr>
  </thead>
  <tbody>
  </tbody>
</table>

Javascript

function InitOverviewDataTable()
{
  oOverviewTable =$('#HelpdeskOverview').dataTable(
  {
    "bPaginate": true,
    "bJQueryUI": true,  // ThemeRoller-stöd
    "bLengthChange": false,
    "bFilter": false,
    "bSort": false,
    "bInfo": true,
    "bAutoWidth": true,
    "bProcessing": true,
    "iDisplayLength": 10,
    "sAjaxSource": '/Helpdesk/ActiveCases/noacceptancetest'
  });
}

function RefreshTable(tableId, urlData)
{
  $.getJSON(urlData, null, function( json )
  {
    table = $(tableId).dataTable();
    oSettings = table.fnSettings();

    table.fnClearTable(this);

    for (var i=0; i<json.aaData.length; i++)
    {
      table.oApi._fnAddData(oSettings, json.aaData[i]);
    }

    oSettings.aiDisplay = oSettings.aiDisplayMaster.slice();
    table.fnDraw();
  });
}

function AutoReload()
{
  RefreshTable('#HelpdeskOverview', '/Helpdesk/ActiveCases/noacceptancetest');

  setTimeout(function(){AutoReload();}, 30000);
}

$(document).ready(function () {
  InitOverviewDataTable();
  setTimeout(function(){AutoReload();}, 30000);
});

Source

typedef struct vs struct definitions

If you use struct without typedef, you'll always have to write

struct mystruct myvar;

It's illegal to write

mystruct myvar;

If you use the typedef you don't need the struct prefix anymore.

Objective-C : BOOL vs bool

The Objective-C type you should use is BOOL. There is nothing like a native boolean datatype, therefore to be sure that the code compiles on all compilers use BOOL. (It's defined in the Apple-Frameworks.

Spring Bean Scopes

Also websocket scope is added:

Scopes a single bean definition to the lifecycle of a WebSocket. Only valid in the context of a web-aware Spring ApplicationContext.

As the per the content of the documentation, there is also thread scope, that is not registered by default.

Multiple radio button groups in MVC 4 Razor

Ok here's how I fixed this

My model is a list of categories. Each category contains a list of its subcategories.
with this in mind, every time in the foreach loop, each RadioButton will have its category's ID (which is unique) as its name attribue.
And I also used Html.RadioButton instead of Html.RadioButtonFor.

Here's the final 'working' pseudo-code:

@foreach (var cat in Model.Categories)
{
  //A piece of code & html here
  @foreach (var item in cat.SubCategories)
  {
     @Html.RadioButton(item.CategoryID.ToString(), item.ID)
  }    
}

The result is:

<input name="127" type="radio" value="110">

Please note that I HAVE NOT put all these radio button groups inside a form. And I don't know if this solution will still work properly in a form.

Thanks to all of the people who helped me solve this ;)

Call japplet from jframe

First of all, Applets are designed to be run from within the context of a browser (or applet viewer), they're not really designed to be added into other containers.

Technically, you can add a applet to a frame like any other component, but personally, I wouldn't. The applet is expecting a lot more information to be available to it in order to allow it to work fully.

Instead, I would move all of the "application" content to a separate component, like a JPanel for example and simply move this between the applet or frame as required...

ps- You can use f.setLocationRelativeTo(null) to center the window on the screen ;)

Updated

You need to go back to basics. Unless you absolutely must have one, avoid applets until you understand the basics of Swing, case in point...

Within the constructor of GalzyTable2 you are doing...

JApplet app = new JApplet(); add(app); app.init(); app.start(); 

...Why are you adding another applet to an applet??

Case in point...

Within the main method, you are trying to add the instance of JFrame to itself...

f.getContentPane().add(f, button2); 

Instead, create yourself a class that extends from something like JPanel, add your UI logical to this, using compound components if required.

Then, add this panel to whatever top level container you need.

Take the time to read through Creating a GUI with Swing

Updated with example

import java.awt.BorderLayout; import java.awt.Dimension; import java.awt.EventQueue; import java.awt.event.ActionEvent; import javax.swing.ImageIcon; import javax.swing.JButton; import javax.swing.JFrame; import javax.swing.JPanel; import javax.swing.JScrollPane; import javax.swing.JTable; import javax.swing.UIManager; import javax.swing.UnsupportedLookAndFeelException;  public class GalaxyTable2 extends JPanel {      private static final int PREF_W = 700;     private static final int PREF_H = 600;      String[] columnNames                     = {"Phone Name", "Brief Description", "Picture", "price",                         "Buy"};  // Create image icons     ImageIcon Image1 = new ImageIcon(                     getClass().getResource("s1.png"));     ImageIcon Image2 = new ImageIcon(                     getClass().getResource("s2.png"));     ImageIcon Image3 = new ImageIcon(                     getClass().getResource("s3.png"));     ImageIcon Image4 = new ImageIcon(                     getClass().getResource("s4.png"));     ImageIcon Image5 = new ImageIcon(                     getClass().getResource("note.png"));     ImageIcon Image6 = new ImageIcon(                     getClass().getResource("note2.png"));     ImageIcon Image7 = new ImageIcon(                     getClass().getResource("note3.png"));      Object[][] rowData = {         {"Galaxy S", "3G Support,CPU 1GHz",             Image1, 120, false},         {"Galaxy S II", "3G Support,CPU 1.2GHz",             Image2, 170, false},         {"Galaxy S III", "3G Support,CPU 1.4GHz",             Image3, 205, false},         {"Galaxy S4", "4G Support,CPU 1.6GHz",             Image4, 230, false},         {"Galaxy Note", "4G Support,CPU 1.4GHz",             Image5, 190, false},         {"Galaxy Note2 II", "4G Support,CPU 1.6GHz",             Image6, 190, false},         {"Galaxy Note 3", "4G Support,CPU 2.3GHz",             Image7, 260, false},};      MyTable ss = new MyTable(                     rowData, columnNames);      // Create a table     JTable jTable1 = new JTable(ss);      public GalaxyTable2() {         jTable1.setRowHeight(70);          add(new JScrollPane(jTable1),                         BorderLayout.CENTER);          JPanel buttons = new JPanel();          JButton button = new JButton("Home");         buttons.add(button);         JButton button2 = new JButton("Confirm");         buttons.add(button2);          add(buttons, BorderLayout.SOUTH);     }      @Override      public Dimension getPreferredSize() {         return new Dimension(PREF_W, PREF_H);     }      public void actionPerformed(ActionEvent e) {         new AMainFrame7().setVisible(true);     }      public static void main(String[] args) {          EventQueue.invokeLater(new Runnable() {             @Override             public void run() {                 try {                     UIManager.setLookAndFeel(UIManager.getSystemLookAndFeelClassName());                 } catch (ClassNotFoundException | InstantiationException | IllegalAccessException | UnsupportedLookAndFeelException ex) {                     ex.printStackTrace();                 }                  JFrame frame = new JFrame("Testing");                 frame.setDefaultCloseOperation(JFrame.EXIT_ON_CLOSE);                 frame.add(new GalaxyTable2());                 frame.pack();                 frame.setLocationRelativeTo(null);                 frame.setVisible(true);             }         });     } } 

You also seem to have a lack of understanding about how to use layout managers.

Take the time to read through Creating a GUI with Swing and Laying components out in a container

can we use xpath with BeautifulSoup?

I can confirm that there is no XPath support within Beautiful Soup.

Simple check for SELECT query empty result

IF EXISTS(SELECT * FROM service s WHERE s.service_id = ?)
 BEGIN
   --DO STUFF HERE

 END

How can I copy a Python string?

You don't need to copy a Python string. They are immutable, and the copy module always returns the original in such cases, as do str(), the whole string slice, and concatenating with an empty string.

Moreover, your 'hello' string is interned (certain strings are). Python deliberately tries to keep just the one copy, as that makes dictionary lookups faster.

One way you could work around this is to actually create a new string, then slice that string back to the original content:

>>> a = 'hello'
>>> b = (a + '.')[:-1]
>>> id(a), id(b)
(4435312528, 4435312432)

But all you are doing now is waste memory. It is not as if you can mutate these string objects in any way, after all.

If all you wanted to know is how much memory a Python object requires, use sys.getsizeof(); it gives you the memory footprint of any Python object.

For containers this does not include the contents; you'd have to recurse into each container to calculate a total memory size:

>>> import sys
>>> a = 'hello'
>>> sys.getsizeof(a)
42
>>> b = {'foo': 'bar'}
>>> sys.getsizeof(b)
280
>>> sys.getsizeof(b) + sum(sys.getsizeof(k) + sys.getsizeof(v) for k, v in b.items())
360

You can then choose to use id() tracking to take an actual memory footprint or to estimate a maximum footprint if objects were not cached and reused.

Adding click event for a button created dynamically using jQuery

Question 1: Use .delegate on the div to bind a click handler to the button.

Question 2: Use $(this).val() or this.value (the latter would be faster) inside of the click handler. this will refer to the button.

$("#pg_menu_content").on('click', '#btn_a', function () {
  alert($(this).val());
});

$div = $('<div data-role="fieldcontain"/>');
$("<input type='button' value='Dynamic Button' id='btn_a' />").appendTo($div.clone()).appendTo('#pg_menu_content');

openCV video saving in python

jveitchmichaelis at https://github.com/ContinuumIO/anaconda-issues/issues/223 provided a thorough answer. Here I copied his answer:

The documentation in OpenCV says (hidden away) that you can only write to avi using OpenCV3. Whether that's true or not I've not been able to determine, but I've been unable to write to anything else.

However, OpenCV is mainly a computer vision library, not a video stream, codec and write one. Therefore, the developers tried to keep this part as simple as possible. Due to this OpenCV for video containers supports only the avi extension, its first version.

From: http://docs.opencv.org/3.1.0/d7/d9e/tutorial_video_write.html

My setup: I built OpenCV 3 from source using MSVC 2015, including ffmpeg. I've also downloaded and installed XVID and openh264 from Cisco, which I added to my PATH. I'm running Anaconda Python 3. I also downloaded a recent build of ffmpeg and added the bin folder to my path, though that shouldn't make a difference as its baked into OpenCV.

I'm running in Win 10 64-bit.

This code seems to work fine on my computer. It will generate a video containing random static:

writer = cv2.VideoWriter("output.avi",
cv2.VideoWriter_fourcc(*"MJPG"), 30,(640,480))

for frame in range(1000):
    writer.write(np.random.randint(0, 255, (480,640,3)).astype('uint8'))

writer.release()

Some things I've learned through trial and error:

  • Only use '.avi', it's just a container, the codec is the important thing.
  • Be careful with specifying frame sizes. In the constructor you need to pass the frame size as (column, row) e.g. 640x480. However the array you pass in, is indexed as (row, column). See in the above example how it's switched?

  • If your input image has a different size to the VideoWriter, it will fail (often silently)

  • Only pass in 8 bit images, manually cast your arrays if you have to (.astype('uint8'))
  • In fact, never mind, just always cast. Even if you load in images using cv2.imread, you need to cast to uint8...
  • MJPG will fail if you don't pass in a 3 channel, 8-bit image. I get an assertion failure for this at least.
  • XVID also requires a 3 channel image but fails silently if you don't do this.
  • H264 seems to be fine with a single channel image
  • If you need raw output, say from a machine vision camera, you can use 'DIB '. 'RAW ' or an empty codec sometimes works. Oddly if I use DIB, I get an ffmpeg error, but the video is saved fine. If I use RAW, there isn't an error, but Windows Video player won't open it. All are fine in VLC.

In the end I think the key point is that OpenCV is not designed to be a video capture library - it doesn't even support sound. VideoWriter is useful, but 99% of the time you're better off saving all your images into a folder and using ffmpeg to turn them into a useful video.

How to convert a private key to an RSA private key?

To Convert BEGIN OPENSSH PRIVATE KEY to BEGIN RSA PRIVATE KEY:

ssh-keygen -p -m PEM -f ~/.ssh/id_rsa

Handle Guzzle exception and get HTTP body

if put 'http_errors' => false in guzzle request options, then it would stop throw exception while get 4xx or 5xx error, like this: $client->get(url, ['http_errors' => false]). then you parse the response, not matter it's ok or error, it would be in the response for more info

HTML5 Video Autoplay not working correctly

Mobile browsers generally ignore this attribute to prevent consuming data until user explicitly starts the download.

UPDATE: newer version of mobile browser on Android and iOS do support autoplay function. But it only works if the video is muted or has no audio channel:

Some additional info: https://webkit.org/blog/6784/new-video-policies-for-ios/

Is double square brackets [[ ]] preferable over single square brackets [ ] in Bash?

In a question tagged 'bash' that explicitly has "in Bash" in the title, I'm a little surprised by all of the replies saying you should avoid [[...]] because it only works in bash!

It's true that portability is the primary objection: if you want to write a shell script which works in Bourne-compatible shells even if they aren't bash, you should avoid [[...]]. (And if you want to test your shell scripts in a more strictly POSIX shell, I recommend dash; though it is an incomplete POSIX implementation since it lacks the internationalization support required by the standard, it also lacks support for the many non-POSIX constructs found in bash, ksh, zsh, etc.)

The other objection I see is at least applicable within the assumption of bash: that [[...]] has its own special rules which you have to learn, while [...] acts like just another command. That is again true (and Mr. Santilli brought the receipts showing all the differences), but it's rather subjective whether the differences are good or bad. I personally find it freeing that the double-bracket construct lets me use (...) for grouping, && and || for Boolean logic, < and > for comparison, and unquoted parameter expansions. It's like its own little closed-off world where expressions work more like they do in traditional, non-command-shell programming languages.

A point I haven't seen raised is that this behavior of [[...]] is entirely consistent with that of the arithmetic expansion construct $((...)), which is specified by POSIX, and also allows unquoted parentheses and Boolean and inequality operators (which here perform numeric instead of lexical comparisons). Essentially, any time you see the doubled bracket characters you get the same quote-shielding effect.

(Bash and its modern relatives also use ((...)) – without the leading $ – as either a C-style for loop header or an environment for performing arithmetic operations; neither syntax is part of POSIX.)

So there are some good reasons to prefer [[...]]; there are also reasons to avoid it, which may or may not be applicable in your environment. As to your coworker, "our style guide says so" is a valid justification, as far as it goes, but I'd also seek out backstory from someone who understands why the style guide recommends what it does.

Make a negative number positive

Just call Math.abs. For example:

int x = Math.abs(-5);

Which will set x to 5.

Note that if you pass Integer.MIN_VALUE, the same value (still negative) will be returned, as the range of int does not allow the positive equivalent to be represented.

How to get phpmyadmin username and password

I had a problem with this. I didn't even create any passwords so I was confused. I googled it and I found out that I should just write root as username and than click GO. I hope it helps.

adb doesn't show nexus 5 device

For those who are still frustrated, if you are using the experimental ART runtime, try switching back to dalvik (in developer options on device)

How can I find the version of the Fedora I use?

These commands worked for Artik 10 :

  • cat /etc/fedora-release
  • cat /etc/issue
  • hostnamectl

and these others didn't :

  • lsb_release -a
  • uname -a

How to completely remove a dialog on close

I use this function in all my js projects

You call it: hideAndResetModals("#IdModalDialog")

You define if:

function hideAndResetModals(modalID)
{
    $(modalID).modal('hide');
    clearValidation(modalID); //You implement it if you need it. If not, you can remote this line
    $(modalID).on('hidden.bs.modal', function () 
    {
        $(modalID).find('form').trigger('reset');  
    });
}

Getting raw SQL query string from PDO prepared statements

Mike's answer is working good until you are using the "re-use" bind value.
For example:

SELECT * FROM `an_modules` AS `m` LEFT JOIN `an_module_sites` AS `ms` ON m.module_id = ms.module_id WHERE 1 AND `module_enable` = :module_enable AND `site_id` = :site_id AND (`module_system_name` LIKE :search OR `module_version` LIKE :search)

The Mike's answer can only replace first :search but not the second.
So, I rewrite his answer to work with multiple parameters that can re-used properly.

public function interpolateQuery($query, $params) {
    $keys = array();
    $values = $params;
    $values_limit = [];

    $words_repeated = array_count_values(str_word_count($query, 1, ':_'));

    # build a regular expression for each parameter
    foreach ($params as $key => $value) {
        if (is_string($key)) {
            $keys[] = '/:'.$key.'/';
            $values_limit[$key] = (isset($words_repeated[':'.$key]) ? intval($words_repeated[':'.$key]) : 1);
        } else {
            $keys[] = '/[?]/';
            $values_limit = [];
        }

        if (is_string($value))
            $values[$key] = "'" . $value . "'";

        if (is_array($value))
            $values[$key] = "'" . implode("','", $value) . "'";

        if (is_null($value))
            $values[$key] = 'NULL';
    }

    if (is_array($values)) {
        foreach ($values as $key => $val) {
            if (isset($values_limit[$key])) {
                $query = preg_replace(['/:'.$key.'/'], [$val], $query, $values_limit[$key], $count);
            } else {
                $query = preg_replace(['/:'.$key.'/'], [$val], $query, 1, $count);
            }
        }
        unset($key, $val);
    } else {
        $query = preg_replace($keys, $values, $query, 1, $count);
    }
    unset($keys, $values, $values_limit, $words_repeated);

    return $query;
}

Dropdown using javascript onchange

Something like this should do the trick

<select id="leave" onchange="leaveChange()">
  <option value="5">Get Married</option>
  <option value="100">Have a Baby</option>
  <option value="90">Adopt a Child</option>
  <option value="15">Retire</option>
  <option value="15">Military Leave</option>
  <option value="15">Medical Leave</option>
</select>

<div id="message"></div>

Javascript

function leaveChange() {
    if (document.getElementById("leave").value != "100"){
        document.getElementById("message").innerHTML = "Common message";
    }     
    else{
        document.getElementById("message").innerHTML = "Having a Baby!!";
    }        
}

jsFiddle Demo

A shorter version and more general could be

HTML

<select id="leave" onchange="leaveChange(this)">
  <option value="5">Get Married</option>
  <option value="100">Have a Baby</option>
  <option value="90">Adopt a Child</option>
  <option value="15">Retire</option>
  <option value="15">Military Leave</option>
  <option value="15">Medical Leave</option>
</select>

Javascript

function leaveChange(control) {
    var msg = control.value == "100" ? "Having a Baby!!" : "Common message";
    document.getElementById("message").innerHTML = msg;
}

Concatenate String in String Objective-c

simple one:

[[@"first" stringByAppendingString:@"second"] stringByAppendingString:@"third"];

if you have many STRINGS to Concatenate, you should use NSMutableString for better performance

Ruby Hash to array of values

Also, a bit simpler....

>> hash = { "a"=>["a", "b", "c"], "b"=>["b", "c"] }
=> {"a"=>["a", "b", "c"], "b"=>["b", "c"]}
>> hash.values
=> [["a", "b", "c"], ["b", "c"]]

Ruby doc here

Error:Failed to open zip file. Gradle's dependency cache may be corrupt

Go to Project pane> Android > Gradle Scripts and open "graddle-wrapper.properties" file check the distribution URL:

enter image description here

Go to your ".gradle/wrapper/dists/" folder and remove that file for me it was "gradle-5.6.4-all"

enter image description here

Then go back to android studio and click on File > Sync Project with Gradle Files. And it will start to download again

enter image description here

Got a NumberFormatException while trying to parse a text file for objects

The problem might be your split() call. Try just split(" ") without the square brackets.

How do you get a directory listing in C?

The following POSIX program will print the names of the files in the current directory:

#define _XOPEN_SOURCE 700
#include <stdio.h>
#include <sys/types.h>
#include <dirent.h>

int main (void)
{
  DIR *dp;
  struct dirent *ep;     
  dp = opendir ("./");

  if (dp != NULL)
  {
    while (ep = readdir (dp))
      puts (ep->d_name);

    (void) closedir (dp);
  }
  else
    perror ("Couldn't open the directory");

  return 0;
}

Credit: http://www.gnu.org/software/libtool/manual/libc/Simple-Directory-Lister.html

Tested in Ubuntu 16.04.

Replacing characters in Ant property

Here is the solution without scripting and no external jars like ant-conrib:

The trick is to use ANT's resources:

  • There is one resource type called "propertyresource" which is like a source file, but provides an stream from the string value of this resource. So you can load it and use it in any task like "copy" that accepts files
  • There is also the task "loadresource" that can load any resource to a property (e.g., a file), but this one could also load our propertyresource. This task allows for filtering the input by applying some token transformations. Finally the following will do what you want:
<loadresource property="propB">
  <propertyresource name="propA"/>
  <filterchain>
    <tokenfilter>
      <filetokenizer/>
      <replacestring from=" " to="_"/>
    </tokenfilter>
  </filterchain>
</loadresource>

This one will replace all " " in propA by "_" and place the result in propB. "filetokenizer" treats the whole input stream (our property) as one token and appies the string replacement on it.

You can do other fancy transformations using other tokenfilters: http://ant.apache.org/manual/Types/filterchain.html

PHP simple foreach loop with HTML

This will work although when embedding PHP in HTML it is better practice to use the following form:

<table>
    <?php foreach($array as $key=>$value): ?>
    <tr>
        <td><?= $key; ?></td>
    </tr>
    <?php endforeach; ?>
</table>

You can find the doc for the alternative syntax on PHP.net

Check if a string is a date value

I would do this

var myDateStr= new Date("2015/5/2");

if( ! isNaN ( myDateStr.getMonth() )) {
    console.log("Valid date");
}
else {
    console.log("Invalid date");
}

Play here

Reducing the gap between a bullet and text in a list item

Try this....

ul.list-group li {
     padding-left: 13px;
     position: relative;
}

ul.list-group li:before {
     left: 0 !important;
     position: absolute;
}

Android: Proper Way to use onBackPressed() with Toast

You don't need a counter for back presses.

Just store a reference to the toast that is shown:

private Toast backtoast;

Then,

public void onBackPressed() {
    if(USER_IS_GOING_TO_EXIT) {
        if(backtoast!=null&&backtoast.getView().getWindowToken()!=null) {
            finish();
        } else {
            backtoast = Toast.makeText(this, "Press back to exit", Toast.LENGTH_SHORT);
            backtoast.show();
        }
    } else {
        //other stuff...
        super.onBackPressed();
    }
}

This will call finish() if you press back while the toast is still visible, and only if the back press would result in exiting the application.

Complex nesting of partials and templates

Angular ui-router supports nested views. I haven't used it yet but looks very promising.

http://angular-ui.github.io/ui-router/

What is the difference between Visual Studio Express 2013 for Windows and Visual Studio Express 2013 for Windows Desktop?

More importantly, the 2013 versions of Visual Studio Express have all the languages that comes with the commercial versions. You can use the Windows desktop versions not only to program using Windows Forms, it is possible to write those windowed applications with any language that comes with the software, may it be C++ using the windows.h header if you want to actually learn how to create windows applications from scratch, or use Windows form to create windows in C# or visual Basic.

In the past, you had to download one version for each language or type of content. Or just download an all-in-one that still installed separate versions of the software for different languages. Now with 2013 you get all the languages needed in each content oriented version of the 2013 express.

You pick what matters the most to you.

Besides, it might be a good way to learn using notepad and the command line to write and compile, but I find that a bit tedious to use. While using an IDE might be overwhelming at first, you start small, learning how to create a project, write code, compile your code. They have gone way over their heads to ease up your day when you take it for the first time.

Nginx subdomain configuration

You could move the common parts to another configuration file and include from both server contexts. This should work:

server {
  listen 80;
  server_name server1.example;
  ...
  include /etc/nginx/include.d/your-common-stuff.conf;
}

server {
  listen 80;
  server_name another-one.example;
  ...
  include /etc/nginx/include.d/your-common-stuff.conf;
}

Edit: Here's an example that's actually copied from my running server. I configure my basic server settings in /etc/nginx/sites-enabled (normal stuff for nginx on Ubuntu/Debian). For example, my main server bunkus.org's configuration file is /etc/nginx/sites-enabled and it looks like this:

server {
  listen   80 default_server;
  listen   [2a01:4f8:120:3105::101:1]:80 default_server;

  include /etc/nginx/include.d/all-common;
  include /etc/nginx/include.d/bunkus.org-common;
  include /etc/nginx/include.d/bunkus.org-80;
}

server {
  listen   443 default_server;
  listen   [2a01:4f8:120:3105::101:1]:443 default_server;

  include /etc/nginx/include.d/all-common;
  include /etc/nginx/include.d/ssl-common;
  include /etc/nginx/include.d/bunkus.org-common;
  include /etc/nginx/include.d/bunkus.org-443;
}

As an example here's the /etc/nginx/include.d/all-common file that's included from both server contexts:

index index.html index.htm index.php .dirindex.php;
try_files $uri $uri/ =404;

location ~ /\.ht {
  deny all;
}

location = /favicon.ico {
  log_not_found off;
  access_log off;
}

location ~ /(README|ChangeLog)$ {
  types { }
  default_type text/plain;
}

What is the difference between join and merge in Pandas?

To put it analogously to SQL "Pandas merge is to outer/inner join and Pandas join is to natural join". Hence when you use merge in pandas, you want to specify which kind of sqlish join you want to use whereas when you use pandas join, you really want to have a matching column label to ensure it joins

Foreach Control in form, how can I do something to all the TextBoxes in my Form?

I found this to work very well, but initially I have my textboxes on a panel so none of my textboxes cleared as expected so I added

this.panel1.Controls.....  

Which got me to thinking that is you have lots of textboxes for different functions and only some need to be cleared out, perhaps using the multiple panel hierarchies you can target just a few and not all.

foreach ( TextBox tb in this.Controls.OfType<TextBox>()) {
  ..
}

What are the RGB codes for the Conditional Formatting 'Styles' in Excel?

Light red fill with dark red text.

{'bg_color':   '#FFC7CE', 'font_color': '#9C0006'})

Light yellow fill with dark yellow text.

{'bg_color':   '#FFEB9C', 'font_color': '#9C6500'})

Green fill with dark green text.

{'bg_color':   '#C6EFCE', 'font_color': '#006100'})

Jackson - Deserialize using generic class

You can wrap it in another class which knows the type of your generic type.

Eg,

class Wrapper {
 private Data<Something> data;
}
mapper.readValue(jsonString, Wrapper.class);

Here Something is a concrete type. You need a wrapper per reified type. Otherwise Jackson does not know what objects to create.

Reading and displaying data from a .txt file

You most likely will want to use the FileInputStream class:

int character;
StringBuffer buffer = new StringBuffer("");
FileInputStream inputStream = new FileInputStream(new File("/home/jessy/file.txt"));

while( (character = inputStream.read()) != -1)
        buffer.append((char) character);

inputStream.close();
System.out.println(buffer);

You will also want to catch some of the exceptions thrown by the read() method and FileInputStream constructor, but those are implementation details specific to your project.

Validate IPv4 address in Java

the lib of apache-httpcomponents

// ipv4 is true
assertTrue(InetAddressUtils.isIPv4Address("127.0.0.1"));
// not detect the ipv6
assertFalse(InetAddressUtils.isIPv4Address("2001:0db8:85a3:0000:0000:8a2e:0370:7334"));

maven lib (update Sep, 2019)

<!-- https://mvnrepository.com/artifact/org.apache.httpcomponents/httpclient -->
<dependency>
    <groupId>org.apache.httpcomponents</groupId>
    <artifactId>httpclient</artifactId>
    <version>4.5.10</version>
</dependency>

How do I view the SSIS packages in SQL Server Management Studio?

The wizard likely created the package as a file. Do a search on your system for files with an extension of .dtsx. This is the actual "SSIS Package" file.

As for loading it in Management Studio, you don't actually view it through there. If you have SQL Server 2005 loaded on your machine, look in the program group. You should find an application with the same icon as Visual Studio called "SQL Server Business Intelligence Development Studio". It's basically a stripped down version of VS 2005 which allows you to create SSIS packages.

Create a blank solution and add your .dtsx file to that to edit/view it.

How do I get NuGet to install/update all the packages in the packages.config?

I'm using visual studio 2015 and the solutions given above didn't work for me, so i did the following:

Delete the packages folder from my solution and also bin and obj folders from every project in the solution and give it a rebuild.

Maybe you will have the next error:

unable to locate nuget.exe

To solve this: Change this line in your NuGet.targets file and setting it to true:

<DownloadNuGetExe Condition=" '$(DownloadNuGetExe)' == '' ">true</DownloadNuGetExe>

Reference:https://stackoverflow.com/a/30918648 and https://stackoverflow.com/a/20502049

Bypass invalid SSL certificate errors when calling web services in .Net

Alternatively you can register a call back delegate which ignores the certification error:

...
ServicePointManager.ServerCertificateValidationCallback = MyCertHandler;
...

static bool MyCertHandler(object sender, X509Certificate certificate, X509Chain chain, SslPolicyErrors error)
{
// Ignore errors
return true;
}

When do I need a fb:app_id or fb:admins?

Including the fb:app_id tag in your HTML HEAD will allow the Facebook scraper to associate the Open Graph entity for that URL with an application. This will allow any admins of that app to view Insights about that URL and any social plugins connected with it.

The fb:admins tag is similar, but allows you to just specify each user ID that you would like to give the permission to do the above.

You can include either of these tags or both, depending on how many people you want to admin the Insights, etc. A single as fb:admins is pretty much a minimum requirement. The rest of the Open Graph tags will still be picked up when people share and like your URL, however it may cause problems in the future, so please include one of the above.

fb:admins is specified like this:
<meta property="fb:admins" content="USER_ID"/>
OR
<meta property="fb:admins" content="USER_ID,USER_ID2,USER_ID3"/>

and fb:app_id like this:
<meta property="fb:app_id" content="APPID"/>

curl: (35) SSL connect error

curl 7.19.7 (x86_64-redhat-linux-gnu) libcurl/7.19.7 NSS/3.19.1 Basic ECC zlib/1.2.3 libidn/1.18 libssh2/1.4.2

You are using a very old version of curl. My guess is that you run into the bug described 6 years ago. Fix is to update your curl.

How to capture a backspace on the onkeydown event

event.key === "Backspace" or "Delete"

More recent and much cleaner: use event.key. No more arbitrary number codes!

input.addEventListener('keydown', function(event) {
    const key = event.key; // const {key} = event; ES6+
    if (key === "Backspace" || key === "Delete") {
        return false;
    }
});

Mozilla Docs

Supported Browsers

How to change the plot line color from blue to black?

The usual way to set the line color in matplotlib is to specify it in the plot command. This can either be done by a string after the data, e.g. "r-" for a red line, or by explicitely stating the color argument.

import matplotlib.pyplot as plt

plt.plot([1,2,3], [2,3,1], "r-") # red line
plt.plot([1,2,3], [5,5,3], color="blue") # blue line

plt.show()

See also the plot command's documentation.

In case you already have a line with a certain color, you can change that with the lines2D.set_color() method.

line, = plt.plot([1,2,3], [4,5,3], color="blue")
line.set_color("black")


Setting the color of a line in a pandas plot is also best done at the point of creating the plot:

import matplotlib.pyplot as plt
import pandas as pd

df = pd.DataFrame({ "x" : [1,2,3,5], "y" : [3,5,2,6]})
df.plot("x", "y", color="r") #plot red line

plt.show()

If you want to change this color later on, you can do so by

plt.gca().get_lines()[0].set_color("black")

This will get you the first (possibly the only) line of the current active axes.
In case you have more axes in the plot, you could loop through them

for ax in plt.gcf().axes:
    ax.get_lines()[0].set_color("black")

and if you have more lines you can loop over them as well.

Abort a Git Merge

Truth be told there are many, many resources explaining how to do this already out on the web:

Git: how to reverse-merge a commit?

Git: how to reverse-merge a commit?

Undoing Merges, from Git's blog (retrieved from archive.org's Wayback Machine)

So I guess I'll just summarize some of these:

  1. git revert <merge commit hash>
    This creates an extra "revert" commit saying you undid a merge

  2. git reset --hard <commit hash *before* the merge>
    This reset history to before you did the merge. If you have commits after the merge you will need to cherry-pick them on to afterwards.

But honestly this guide here is better than anything I can explain, with diagrams! :)

Android: how do I check if activity is running?

Not sure it is a "proper" way to "do things".
If there's no API way to resolve the (or a) question than you should think a little, maybe you're doing something wrong and read more docs instead etc.
(As I understood static variables is a commonly wrong way in android. Of cause it could work, but there definitely will be cases when it wont work[for example, in production, on million devices]).
Exactly in your case I suggest to think why do you need to know if another activity is alive?.. you can start another activity for result to get its functionality. Or you can derive the class to obtain its functionality and so on.
Best Regards.

C++11 rvalues and move semantics confusion (return statement)

None of those will do any extra copying. Even if RVO isn't used, the new standard says that move construction is preferred to copy when doing returns I believe.

I do believe that your second example causes undefined behavior though because you're returning a reference to a local variable.

Python TypeError: not enough arguments for format string

I got the same error when using % as a percent character in my format string. The solution to this is to double up the %%.

Get RETURN value from stored procedure in SQL

This should work for you. Infact the one which you are thinking will also work:-

 .......
 DECLARE @returnvalue INT

 EXEC @returnvalue = SP_One
 .....

How to manually trigger validation with jQuery validate?

As written in the documentation, the way to trigger form validation programmatically is to invoke validator.form()

var validator = $( "#myform" ).validate();
validator.form();

How do I get a substring of a string in Python?

If myString contains an account number that begins at offset 6 and has length 9, then you can extract the account number this way: acct = myString[6:][:9].

If the OP accepts that, they might want to try, in an experimental fashion,

myString[2:][:999999]

It works - no error is raised, and no default 'string padding' occurs.

What is the "__v" field in Mongoose

For remove in NestJS need to add option to Shema() decorator

@Schema({ versionKey: false })

How to stop an unstoppable zombie job on Jenkins without restarting the server?

I had same issue at the last half hour...

Was not able to delete a zombie build running in my multi-branch pipeline. Even Server restarts by UI or even from commandline via sudo service jenkins restart did block the execution... The build was not stoppable... It always reapeared.

Used Version: Jenkins ver 2.150.2

I was very annoyed, but... when looking into the log of the build I found something intersting at the end of the log:

Logfile output of an zombie build and showing restart did not stop it

The red marked parts are the "frustrating parts"... As you can see I always wanted to Abort the build from UI but it did not work...

But there is a hyperlink with text Click here to forcibly terminate running steps...(first green one) Now I pressed the link...) After the link execution a message about Still paused appeared with another Link Click here to forcibily kill entire build (second green one) After pressing this link also the build finally was hard killed...

So this seems to work without any special plugins (except the multibranch-pipeline build plugin itself).

jquery - fastest way to remove all rows from a very large table

Using detach is magnitudes faster than any of the other answers here:

$('#mytable').find('tbody').detach();

Don't forget to put the tbody element back into the table since detach removed it:

$('#mytable').append($('<tbody>'));  

Also note that when talking efficiency $(target).find(child) syntax is faster than $(target > child). Why? Sizzle!

Elapsed Time to Empty 3,161 Table Rows

Using the Detach() method (as shown in my example above):

  • Firefox: 0.027s
  • Chrome: 0.027s
  • Edge: 1.73s
  • IE11: 4.02s

Using the empty() method:

  • Firefox: 0.055s
  • Chrome: 0.052s
  • Edge: 137.99s (might as well be frozen)
  • IE11: Freezes and never returns

How to load image to WPF in runtime?

In WPF an image is typically loaded from a Stream or an Uri.

BitmapImage supports both and an Uri can even be passed as constructor argument:

var uri = new Uri("http://...");
var bitmap = new BitmapImage(uri);

If the image file is located in a local folder, you would have to use a file:// Uri. You could create such a Uri from a path like this:

var path = Path.Combine(Environment.CurrentDirectory, "Bilder", "sas.png");
var uri = new Uri(path);

If the image file is an assembly resource, the Uri must follow the the Pack Uri scheme:

var uri = new Uri("pack://application:,,,/Bilder/sas.png");

In this case the Visual Studio Build Action for sas.png would have to be Resource.

Once you have created a BitmapImage and also have an Image control like in this XAML

<Image Name="image1" />

you would simply assign the BitmapImage to the Source property of that Image control:

image1.Source = bitmap;

How to mount a host directory in a Docker container

Had the same problem. Found this in the docker documentation:

Note: The host directory is, by its nature, host-dependent. For this reason, you can’t mount a host directory from Dockerfile, the VOLUME instruction does not support passing a host-dir, because built images should be portable. A host directory wouldn’t be available on all potential hosts.

So, mounting a read/write host directory is only possible with the -v parameter in the docker run command, as the other answers point out correctly.

java.util.regex - importance of Pattern.compile()?

The compile() method is always called at some point; it's the only way to create a Pattern object. So the question is really, why should you call it explicitly? One reason is that you need a reference to the Matcher object so you can use its methods, like group(int) to retrieve the contents of capturing groups. The only way to get ahold of the Matcher object is through the Pattern object's matcher() method, and the only way to get ahold of the Pattern object is through the compile() method. Then there's the find() method which, unlike matches(), is not duplicated in the String or Pattern classes.

The other reason is to avoid creating the same Pattern object over and over. Every time you use one of the regex-powered methods in String (or the static matches() method in Pattern), it creates a new Pattern and a new Matcher. So this code snippet:

for (String s : myStringList) {
    if ( s.matches("\\d+") ) {
        doSomething();
    }
}

...is exactly equivalent to this:

for (String s : myStringList) {
    if ( Pattern.compile("\\d+").matcher(s).matches() ) {
        doSomething();
    }
}

Obviously, that's doing a lot of unnecessary work. In fact, it can easily take longer to compile the regex and instantiate the Pattern object, than it does to perform an actual match. So it usually makes sense to pull that step out of the loop. You can create the Matcher ahead of time as well, though they're not nearly so expensive:

Pattern p = Pattern.compile("\\d+");
Matcher m = p.matcher("");
for (String s : myStringList) {
    if ( m.reset(s).matches() ) {
        doSomething();
    }
}

If you're familiar with .NET regexes, you may be wondering if Java's compile() method is related to .NET's RegexOptions.Compiled modifier; the answer is no. Java's Pattern.compile() method is merely equivalent to .NET's Regex constructor. When you specify the Compiled option:

Regex r = new Regex(@"\d+", RegexOptions.Compiled); 

...it compiles the regex directly to CIL byte code, allowing it to perform much faster, but at a significant cost in up-front processing and memory use--think of it as steroids for regexes. Java has no equivalent; there's no difference between a Pattern that's created behind the scenes by String#matches(String) and one you create explicitly with Pattern#compile(String).

(EDIT: I originally said that all .NET Regex objects are cached, which is incorrect. Since .NET 2.0, automatic caching occurs only with static methods like Regex.Matches(), not when you call a Regex constructor directly. ref)

What is *.o file?

A .o object file file (also .obj on Windows) contains compiled object code (that is, machine code produced by your C or C++ compiler), together with the names of the functions and other objects the file contains. Object files are processed by the linker to produce the final executable. If your build process has not produced these files, there is probably something wrong with your makefile/project files.

Why does the PHP json_encode function convert UTF-8 strings to hexadecimal entities?

Here is my combined solution for various PHP versions.

In my company we are working with different servers with various PHP versions, so I had to find solution working for all.

$phpVersion = substr(phpversion(), 0, 3)*1;

if($phpVersion >= 5.4) {
  $encodedValue = json_encode($value, JSON_UNESCAPED_UNICODE);
} else {
  $encodedValue = preg_replace('/\\\\u([a-f0-9]{4})/e', "iconv('UCS-4LE','UTF-8',pack('V', hexdec('U$1')))", json_encode($value));
}

Credits should go to Marco Gasi & abu. The solution for PHP >= 5.4 is provided in the json_encode docs.

How can I display an RTSP video stream in a web page?

Roughly you can have 3 choices to display RTSP video stream in a web page:

  1. Realplayer
  2. Quicktime player
  3. VLC player

You can find the code to embed the activeX via google search.

As far as I know, there are some limitations for each player.

  1. Realplayer does not support H.264 video natively, you must install a quicktime plugin for Realplayer to achieve H.264 decoding.
  2. Quicktime player does not support RTP/AVP/TCP transport, and it's RTP/AVP (UDP) transport does not include NAT hole punching. Thus the only feasible transport is HTTP tunneling in WAN deployment.
  3. VLC neither supports NAT hole punching for RTP/AVP transport, but RTP/AVP/TCP transport is available.

Best way to work with transactions in MS SQL Server Management Studio

The easisest thing to do is to wrap your code in a transaction, and then execute each batch of T-SQL code line by line.

For example,

Begin Transaction

         -Do some T-SQL queries here.

Rollback transaction -- OR commit transaction

If you want to incorporate error handling you can do so by using a TRY...CATCH BLOCK. Should an error occur you can then rollback the tranasction within the catch block.

For example:

USE AdventureWorks;
GO
BEGIN TRANSACTION;

BEGIN TRY
    -- Generate a constraint violation error.
    DELETE FROM Production.Product
    WHERE ProductID = 980;
END TRY
BEGIN CATCH
    SELECT 
        ERROR_NUMBER() AS ErrorNumber
        ,ERROR_SEVERITY() AS ErrorSeverity
        ,ERROR_STATE() AS ErrorState
        ,ERROR_PROCEDURE() AS ErrorProcedure
        ,ERROR_LINE() AS ErrorLine
        ,ERROR_MESSAGE() AS ErrorMessage;

    IF @@TRANCOUNT > 0
        ROLLBACK TRANSACTION;
END CATCH;

IF @@TRANCOUNT > 0
    COMMIT TRANSACTION;
GO

See the following link for more details.

http://msdn.microsoft.com/en-us/library/ms175976.aspx

Hope this helps but please let me know if you need more details.

Setting values of input fields with Angular 6

You should use the following:

       <td><input id="priceInput-{{orderLine.id}}" type="number" [(ngModel)]="orderLine.price"></td>

You will need to add the FormsModule to your app.module in the inputs section as follows:

import { FormsModule } from '@angular/forms';

@NgModule({
  declarations: [
    ...
  ],
  imports: [
    BrowserModule,
    FormsModule
  ],
  ..

The use of the brackets around the ngModel are as follows:

  • The [] show that it is taking an input from your TS file. This input should be a public member variable. A one way binding from TS to HTML.

  • The () show that it is taking output from your HTML file to a variable in the TS file. A one way binding from HTML to TS.

  • The [()] are both (e.g. a two way binding)

See here for more information: https://angular.io/guide/template-syntax

I would also suggest replacing id="priceInput-{{orderLine.id}}" with something like this [id]="getElementId(orderLine)" where getElementId(orderLine) returns the element Id in the TS file and can be used anywere you need to reference the element (to avoid simple bugs like calling it priceInput1 in one place and priceInput-1 in another. (if you still need to access the input by it's Id somewhere else)

Python sys.argv lists and indexes

As explained in the different asnwers already, sys.argv contains the command line arguments that called your Python script.

However, Python comes with libraries that help you parse command line arguments very easily. Namely, the new standard argparse. Using argparse would spare you the need to write a lot of boilerplate code.

How to Read from a Text File, Character by Character in C++

There is no reason not to use C <stdio.h> in C++, and in fact it is often the optimal choice.

#include <stdio.h>

int
main()  // (void) not necessary in C++
{
    int c;
    while ((c = getchar()) != EOF) {
        // do something with 'c' here
    }
    return 0; // technically not necessary in C++ but still good style
}

What's the fastest way to loop through an array in JavaScript?

2014 While is back

Just think logical.

Look at this

for( var index = 0 , length = array.length ; index < length ; index++ ) {

 //do stuff

}
  1. Need to create at least 2 variables (index,length)
  2. Need to check if the index is smaller than the length
  3. Need to increase the index
  4. the for loop has 3 parameters

Now tell me why this should be faster than:

var length = array.length;

while( --length ) { //or length--

 //do stuff

}
  1. One variable
  2. No checks
  3. the index is decreased (Machines prefer that)
  4. while has only one parameter

I was totally confused when Chrome 28 showed that the for loop is faster than the while. This must have ben some sort of

"Uh, everyone is using the for loop, let's focus on that when developing for chrome."

But now, in 2014 the while loop is back on chrome. it's 2 times faster , on other/older browsers it was always faster.

Lately i made some new tests. Now in real world envoirement those short codes are worth nothing and jsperf can't actually execute properly the while loop, because it needs to recreate the array.length which also takes time.

you CAN'T get the actual speed of a while loop on jsperf.

you need to create your own custom function and check that with window.performance.now()

And yeah... there is no way the while loop is simply faster.

The real problem is actually the dom manipulation / rendering time / drawing time or however you wanna call it.

For example i have a canvas scene where i need to calculate the coordinates and collisions... this is done between 10-200 MicroSeconds (not milliseconds). it actually takes various milliseconds to render everything.Same as in DOM.

BUT

There is another super performant way using the for loop in some cases... for example to copy/clone an array

for(
 var i = array.length ;
 i > 0 ;
 arrayCopy[ --i ] = array[ i ] // doing stuff
);

Notice the setup of the parameters:

  1. Same as in the while loop i'm using only one variable
  2. Need to check if the index is bigger than 0;
  3. As you can see this approach is different vs the normal for loop everyone uses, as i do stuff inside the 3th parameter and i also decrease directly inside the array.

Said that, this confirms that machines like the --

writing that i was thinking to make it a little shorter and remove some useless stuff and wrote this one using the same style:

for(
 var i = array.length ;
 i-- ;
 arrayCopy[ i ] = array[ i ] // doing stuff
);

Even if it's shorter it looks like using i one more time slows down everything. It's 1/5 slower than the previous for loop and the while one.

Note: the ; is very important after the for looo without {}

Even if i just told you that jsperf is not the best way to test scripts .. i added this 2 loops here

http://jsperf.com/caching-array-length/40

And here is another answer about performance in javascript

https://stackoverflow.com/a/21353032/2450730

This answer is to show performant ways of writing javascript. So if you can't read that, ask and you will get an answer or read a book about javascript http://www.ecma-international.org/ecma-262/5.1/

initializing strings as null vs. empty string

Empty-ness and "NULL-ness" are two different concepts. As others mentioned the former can be achieved via std::string::empty(), the latter can be achieved with boost::optional<std::string>, e.g.:

boost::optional<string> myStr;
if (myStr) { // myStr != NULL
    // ...
}

Connection attempt failed with "ECONNREFUSED - Connection refused by server"

FTP protocol may be blocked by your ISP firewall, try connecting via SFTP (i.e. use 22 for port num instead of 21 which is simply FTP).

For more information try this link.

Parse DateTime string in JavaScript

I'v been used following code in IE. (IE8 compatible)

var dString = "2013.2.4";
var myDate = new Date( dString.replace(/(\d+)\.(\d+)\.(\d+)/,"$2/$3/$1") );
alert( "my date:"+ myDate );

Project vs Repository in GitHub

GitHub recently introduced a new feature called Projects. This provides a visual board that is typical of many Project Management tools:

Project

A Repository as documented on GitHub:

A repository is the most basic element of GitHub. They're easiest to imagine as a project's folder. A repository contains all of the project files (including documentation), and stores each file's revision history. Repositories can have multiple collaborators and can be either public or private.

A Project as documented on GitHub:

Project boards on GitHub help you organize and prioritize your work. You can create project boards for specific feature work, comprehensive roadmaps, or even release checklists. With project boards, you have the flexibility to create customized workflows that suit your needs.

Part of the confusion is that the new feature, Projects, conflicts with the overloaded usage of the term project in the documentation above.

Format ints into string of hex

''.join('%02x'%i for i in input)

How to iterate over a column vector in Matlab?

for i=1:length(list)
  elm = list(i);
  //do something with elm.

Check if PHP session has already started

You can use the following solution to check if a PHP session has already started:

if(session_id()== '')
{
   echo"Session isn't Start";
}
else
{
    echo"Session Started";
}

How can I alter a primary key constraint using SQL syntax?

you can rename constraint objects using sp_rename (as described in this answer)

for example:

EXEC sp_rename N'schema.MyIOldConstraint', N'MyNewConstraint'

How does it work - requestLocationUpdates() + LocationRequest/Listener

You are implementing LocationListener in your activity MainActivity. The call for concurrent location updates will therefor be like this:

mLocationClient.requestLocationUpdates(mLocationRequest, this);

Be sure that the LocationListener you're implementing is from the google api, that is import this:

import com.google.android.gms.location.LocationListener;

and not this:

import android.location.LocationListener;

and it should work just fine.

It's also important that the LocationClient really is connected before you do this. I suggest you don't call it in the onCreate or onStart methods, but in onResume. It is all explained quite well in the tutorial for Google Location Api: https://developer.android.com/training/location/index.html

MySQL DISTINCT on a GROUP_CONCAT()

Using DISTINCT will work

SELECT GROUP_CONCAT(DISTINCT(categories) SEPARATOR ' ') FROM table

REf:- this

How do I echo and send console output to a file in a bat script?

Yes, there is a way to show a single command output on the console (screen) and in a file. Using your example, use...

@ECHO OFF
FOR /F "tokens=*" %%I IN ('DIR') DO ECHO %%I & ECHO %%I>>windows-dir.txt

Detailed explanation:

The FOR command parses the output of a command or text into a variable, which can be referenced multiple times.

For a command, such as DIR /B, enclose in single quotes as shown in example below. Replace the DIR /B text with your desired command.

FOR /F "tokens=*" %%I IN ('DIR /B') DO ECHO %%I & ECHO %%I>>FILE.TXT

For displaying text, enclose text in double quotes as shown in example below.

FOR /F "tokens=*" %%I IN ("Find this text on console (screen) and in file") DO ECHO %%I & ECHO %%I>>FILE.TXT

... And with line wrapping...

FOR /F "tokens=*" %%I IN ("Find this text on console (screen) and in file") DO (
  ECHO %%I & ECHO %%I>>FILE.TXT
)

If you have times when you want the output only on console (screen), and other times sent only to file, and other times sent to both, specify the "DO" clause of the FOR loop using a variable, as shown below with %TOECHOWHERE%.

@ECHO OFF
FOR %%I IN (TRUE FALSE) DO (
  FOR %%J IN (TRUE FALSE) DO (
    SET TOSCREEN=%%I & SET TOFILE=%%J & CALL :Runit)
)
GOTO :Finish

:Runit
  REM Both TOSCREEN and TOFILE get assigned a trailing space in the FOR loops
  REM above when the FOR loops are evaluating the first item in the list,
  REM "TRUE".  So, the first value of TOSCREEN is "TRUE " (with a trailing
  REM space), the second value is "FALSE" (no trailing or leading space).
  REM Adding the ": =" text after "TOSCREEN" tells the command processor to
  REM remove all spaces from the value in the "TOSCREEN" variable.
  IF "%TOSCREEN: =%"=="TRUE" (
      IF "%TOFILE: =%"=="TRUE" (
          SET TEXT=On screen, and in "FILE.TXT"
          SET TOECHOWHERE="ECHO %%I & ECHO %%I>>FILE.TXT"
        ) ELSE (
          SET TEXT=On screen, not in "FILE.TXT"
          SET TOECHOWHERE="ECHO %%I"
      )
    ) ELSE (
      IF "%TOFILE: =%"=="TRUE" (
          SET TEXT=Not on screen, but in "FILE.TXT"
          SET TOECHOWHERE="ECHO %%I>>FILE.txt"
        ) ELSE (
          SET TEXT=Not on screen, nor in "FILE.TXT"
          SET TOECHOWHERE="ECHO %%I>NUL"
      )
  )
  FOR /F "tokens=*" %%I IN ("%TEXT%") DO %TOECHOWHERE:~1,-1%
GOTO :eof

:Finish
  ECHO Finished [this text to console (screen) only].
  PAUSE

How do you transfer or export SQL Server 2005 data to Excel

I've found an easy way to export query results from SQL Server Management Studio 2005 to Excel.

1) Select menu item Query -> Query Options.

2) Set check box in Results -> Grid -> Include column headers when copying or saving the results.

After that, when you Select All and Copy the query results, you can paste them to Excel, and the column headers will be present.

Problems with installation of Google App Engine SDK for php in OS X

It's likely that the download was corrupted if you are getting an error with the disk image. Go back to the downloads page at https://developers.google.com/appengine/downloads and look at the SHA1 checksum. Then, go to your Terminal app on your mac and run the following:

openssl sha1 [put the full path to the file here without brackets] 

For example:

openssl sha1 /Users/me/Desktop/myFile.dmg 

If you get a different value than the one on the Downloads page, you know your file is not properly downloaded and you should try again.

Printing Lists as Tabular Data

>>> import pandas
>>> pandas.DataFrame(data, teams_list, teams_list)
           Man Utd  Man City  T Hotspur
Man Utd    1        2         1        
Man City   0        1         0        
T Hotspur  2        4         2        

Evaluating a mathematical expression in a string

The reason eval and exec are so dangerous is that the default compile function will generate bytecode for any valid python expression, and the default eval or exec will execute any valid python bytecode. All the answers to date have focused on restricting the bytecode that can be generated (by sanitizing input) or building your own domain-specific-language using the AST.

Instead, you can easily create a simple eval function that is incapable of doing anything nefarious and can easily have runtime checks on memory or time used. Of course, if it is simple math, than there is a shortcut.

c = compile(stringExp, 'userinput', 'eval')
if c.co_code[0]==b'd' and c.co_code[3]==b'S':
    return c.co_consts[ord(c.co_code[1])+ord(c.co_code[2])*256]

The way this works is simple, any constant mathematic expression is safely evaluated during compilation and stored as a constant. The code object returned by compile consists of d, which is the bytecode for LOAD_CONST, followed by the number of the constant to load (usually the last one in the list), followed by S, which is the bytecode for RETURN_VALUE. If this shortcut doesn't work, it means that the user input isn't a constant expression (contains a variable or function call or similar).

This also opens the door to some more sophisticated input formats. For example:

stringExp = "1 + cos(2)"

This requires actually evaluating the bytecode, which is still quite simple. Python bytecode is a stack oriented language, so everything is a simple matter of TOS=stack.pop(); op(TOS); stack.put(TOS) or similar. The key is to only implement the opcodes that are safe (loading/storing values, math operations, returning values) and not unsafe ones (attribute lookup). If you want the user to be able to call functions (the whole reason not to use the shortcut above), simple make your implementation of CALL_FUNCTION only allow functions in a 'safe' list.

from dis import opmap
from Queue import LifoQueue
from math import sin,cos
import operator

globs = {'sin':sin, 'cos':cos}
safe = globs.values()

stack = LifoQueue()

class BINARY(object):
    def __init__(self, operator):
        self.op=operator
    def __call__(self, context):
        stack.put(self.op(stack.get(),stack.get()))

class UNARY(object):
    def __init__(self, operator):
        self.op=operator
    def __call__(self, context):
        stack.put(self.op(stack.get()))


def CALL_FUNCTION(context, arg):
    argc = arg[0]+arg[1]*256
    args = [stack.get() for i in range(argc)]
    func = stack.get()
    if func not in safe:
        raise TypeError("Function %r now allowed"%func)
    stack.put(func(*args))

def LOAD_CONST(context, arg):
    cons = arg[0]+arg[1]*256
    stack.put(context['code'].co_consts[cons])

def LOAD_NAME(context, arg):
    name_num = arg[0]+arg[1]*256
    name = context['code'].co_names[name_num]
    if name in context['locals']:
        stack.put(context['locals'][name])
    else:
        stack.put(context['globals'][name])

def RETURN_VALUE(context):
    return stack.get()

opfuncs = {
    opmap['BINARY_ADD']: BINARY(operator.add),
    opmap['UNARY_INVERT']: UNARY(operator.invert),
    opmap['CALL_FUNCTION']: CALL_FUNCTION,
    opmap['LOAD_CONST']: LOAD_CONST,
    opmap['LOAD_NAME']: LOAD_NAME
    opmap['RETURN_VALUE']: RETURN_VALUE,
}

def VMeval(c):
    context = dict(locals={}, globals=globs, code=c)
    bci = iter(c.co_code)
    for bytecode in bci:
        func = opfuncs[ord(bytecode)]
        if func.func_code.co_argcount==1:
            ret = func(context)
        else:
            args = ord(bci.next()), ord(bci.next())
            ret = func(context, args)
        if ret:
            return ret

def evaluate(expr):
    return VMeval(compile(expr, 'userinput', 'eval'))

Obviously, the real version of this would be a bit longer (there are 119 opcodes, 24 of which are math related). Adding STORE_FAST and a couple others would allow for input like 'x=5;return x+x or similar, trivially easily. It can even be used to execute user-created functions, so long as the user created functions are themselves executed via VMeval (don't make them callable!!! or they could get used as a callback somewhere). Handling loops requires support for the goto bytecodes, which means changing from a for iterator to while and maintaining a pointer to the current instruction, but isn't too hard. For resistance to DOS, the main loop should check how much time has passed since the start of the calculation, and certain operators should deny input over some reasonable limit (BINARY_POWER being the most obvious).

While this approach is somewhat longer than a simple grammar parser for simple expressions (see above about just grabbing the compiled constant), it extends easily to more complicated input, and doesn't require dealing with grammar (compile take anything arbitrarily complicated and reduces it to a sequence of simple instructions).

invalid operands of types int and double to binary 'operator%'

Because % is only defined for integer types. That's the modulus operator.

5.6.2 of the standard:

The operands of * and / shall have arithmetic or enumeration type; the operands of % shall have integral or enumeration type. [...]

As Oli pointed out, you can use fmod(). Don't forget to include math.h.

C# with MySQL INSERT parameters

comm.Parameters.Add("person", "Myname");

Ant if else condition?

You can also do this with ant contrib's if task.

<if>
    <equals arg1="${condition}" arg2="true"/>
    <then>
        <copy file="${some.dir}/file" todir="${another.dir}"/>
    </then>
    <elseif>
        <equals arg1="${condition}" arg2="false"/>
        <then>
            <copy file="${some.dir}/differentFile" todir="${another.dir}"/>
        </then>
    </elseif>
    <else>
        <echo message="Condition was neither true nor false"/>
    </else>
</if>

How do I resolve "HTTP Error 500.19 - Internal Server Error" on IIS7.0

Right now i had this error and resolved it. Your url could match with created virtual directory.

You have to check virtual directories, in my example i found in applicationhost.config next row:

<application path="/" applicationPool="Clr4IntegratedAppPool">
    <virtualDirectory path="/admin/roles" physicalPath="C:\..." />
</application>

I tried to open page with an url (http://localhost/admin/roles) of AdminController and Roles action and got this error.

How to validate an email address using a regular expression?

If you want to improve on a regex that has been working reasonably well over several years, then the answer depends on what exactly you want to achieve - what kinds of email addresses have been failing. Fine-tuning email regexes is very difficult, and I have yet to see a perfect solution.

  • If your application involves something very technical in nature (or something internal to organizations), then maybe you need to support IP addresses instead of domain names, or comments in the "local" part of the email address.
  • If your application is multinational, I would consider focusing on Unicode/UTF8 support.

The leading answer to your question currently links to a "fully RFC-822–compliant regex". However, in spite of the complexity of that regex and its presumed attention to detail in RFC rules, it completely fails when it comes to Unicode support.

The regex that I've written for most of my apps focuses on Unicode support, as well as reasonably good overall adherence to RFC standards:

/^(?!\.)((?!.*\.{2})[a-zA-Z0-9\u0080-\u00FF\u0100-\u017F\u0180-\u024F\u0250-\u02AF\u0300-\u036F\u0370-\u03FF\u0400-\u04FF\u0500-\u052F\u0530-\u058F\u0590-\u05FF\u0600-\u06FF\u0700-\u074F\u0750-\u077F\u0780-\u07BF\u07C0-\u07FF\u0900-\u097F\u0980-\u09FF\u0A00-\u0A7F\u0A80-\u0AFF\u0B00-\u0B7F\u0B80-\u0BFF\u0C00-\u0C7F\u0C80-\u0CFF\u0D00-\u0D7F\u0D80-\u0DFF\u0E00-\u0E7F\u0E80-\u0EFF\u0F00-\u0FFF\u1000-\u109F\u10A0-\u10FF\u1100-\u11FF\u1200-\u137F\u1380-\u139F\u13A0-\u13FF\u1400-\u167F\u1680-\u169F\u16A0-\u16FF\u1700-\u171F\u1720-\u173F\u1740-\u175F\u1760-\u177F\u1780-\u17FF\u1800-\u18AF\u1900-\u194F\u1950-\u197F\u1980-\u19DF\u19E0-\u19FF\u1A00-\u1A1F\u1B00-\u1B7F\u1D00-\u1D7F\u1D80-\u1DBF\u1DC0-\u1DFF\u1E00-\u1EFF\u1F00-\u1FFFu20D0-\u20FF\u2100-\u214F\u2C00-\u2C5F\u2C60-\u2C7F\u2C80-\u2CFF\u2D00-\u2D2F\u2D30-\u2D7F\u2D80-\u2DDF\u2F00-\u2FDF\u2FF0-\u2FFF\u3040-\u309F\u30A0-\u30FF\u3100-\u312F\u3130-\u318F\u3190-\u319F\u31C0-\u31EF\u31F0-\u31FF\u3200-\u32FF\u3300-\u33FF\u3400-\u4DBF\u4DC0-\u4DFF\u4E00-\u9FFF\uA000-\uA48F\uA490-\uA4CF\uA700-\uA71F\uA800-\uA82F\uA840-\uA87F\uAC00-\uD7AF\uF900-\uFAFF\.!#$%&'*+-/=?^_`{|}~\-\d]+)@(?!\.)([a-zA-Z0-9\u0080-\u00FF\u0100-\u017F\u0180-\u024F\u0250-\u02AF\u0300-\u036F\u0370-\u03FF\u0400-\u04FF\u0500-\u052F\u0530-\u058F\u0590-\u05FF\u0600-\u06FF\u0700-\u074F\u0750-\u077F\u0780-\u07BF\u07C0-\u07FF\u0900-\u097F\u0980-\u09FF\u0A00-\u0A7F\u0A80-\u0AFF\u0B00-\u0B7F\u0B80-\u0BFF\u0C00-\u0C7F\u0C80-\u0CFF\u0D00-\u0D7F\u0D80-\u0DFF\u0E00-\u0E7F\u0E80-\u0EFF\u0F00-\u0FFF\u1000-\u109F\u10A0-\u10FF\u1100-\u11FF\u1200-\u137F\u1380-\u139F\u13A0-\u13FF\u1400-\u167F\u1680-\u169F\u16A0-\u16FF\u1700-\u171F\u1720-\u173F\u1740-\u175F\u1760-\u177F\u1780-\u17FF\u1800-\u18AF\u1900-\u194F\u1950-\u197F\u1980-\u19DF\u19E0-\u19FF\u1A00-\u1A1F\u1B00-\u1B7F\u1D00-\u1D7F\u1D80-\u1DBF\u1DC0-\u1DFF\u1E00-\u1EFF\u1F00-\u1FFF\u20D0-\u20FF\u2100-\u214F\u2C00-\u2C5F\u2C60-\u2C7F\u2C80-\u2CFF\u2D00-\u2D2F\u2D30-\u2D7F\u2D80-\u2DDF\u2F00-\u2FDF\u2FF0-\u2FFF\u3040-\u309F\u30A0-\u30FF\u3100-\u312F\u3130-\u318F\u3190-\u319F\u31C0-\u31EF\u31F0-\u31FF\u3200-\u32FF\u3300-\u33FF\u3400-\u4DBF\u4DC0-\u4DFF\u4E00-\u9FFF\uA000-\uA48F\uA490-\uA4CF\uA700-\uA71F\uA800-\uA82F\uA840-\uA87F\uAC00-\uD7AF\uF900-\uFAFF\-\.\d]+)((\.([a-zA-Z\u0080-\u00FF\u0100-\u017F\u0180-\u024F\u0250-\u02AF\u0300-\u036F\u0370-\u03FF\u0400-\u04FF\u0500-\u052F\u0530-\u058F\u0590-\u05FF\u0600-\u06FF\u0700-\u074F\u0750-\u077F\u0780-\u07BF\u07C0-\u07FF\u0900-\u097F\u0980-\u09FF\u0A00-\u0A7F\u0A80-\u0AFF\u0B00-\u0B7F\u0B80-\u0BFF\u0C00-\u0C7F\u0C80-\u0CFF\u0D00-\u0D7F\u0D80-\u0DFF\u0E00-\u0E7F\u0E80-\u0EFF\u0F00-\u0FFF\u1000-\u109F\u10A0-\u10FF\u1100-\u11FF\u1200-\u137F\u1380-\u139F\u13A0-\u13FF\u1400-\u167F\u1680-\u169F\u16A0-\u16FF\u1700-\u171F\u1720-\u173F\u1740-\u175F\u1760-\u177F\u1780-\u17FF\u1800-\u18AF\u1900-\u194F\u1950-\u197F\u1980-\u19DF\u19E0-\u19FF\u1A00-\u1A1F\u1B00-\u1B7F\u1D00-\u1D7F\u1D80-\u1DBF\u1DC0-\u1DFF\u1E00-\u1EFF\u1F00-\u1FFF\u20D0-\u20FF\u2100-\u214F\u2C00-\u2C5F\u2C60-\u2C7F\u2C80-\u2CFF\u2D00-\u2D2F\u2D30-\u2D7F\u2D80-\u2DDF\u2F00-\u2FDF\u2FF0-\u2FFF\u3040-\u309F\u30A0-\u30FF\u3100-\u312F\u3130-\u318F\u3190-\u319F\u31C0-\u31EF\u31F0-\u31FF\u3200-\u32FF\u3300-\u33FF\u3400-\u4DBF\u4DC0-\u4DFF\u4E00-\u9FFF\uA000-\uA48F\uA490-\uA4CF\uA700-\uA71F\uA800-\uA82F\uA840-\uA87F\uAC00-\uD7AF\uF900-\uFAFF]){2,63})+)$/i

I'll avoid copy-pasting complete answers, so I'll just link this to a similar answer I provided here: How to validate a unicode email?

There is also a live demo available for the regex above at: http://jsfiddle.net/aossikine/qCLVH/3/

CSS Div stretch 100% page height

Simple, just wrap it up in a table div...

The HTML:

<div class="fake-table">
   <div class="left-side">
     some text
   </div>
   <div class="right-side">
     My Navigation or something
   </div>
</div>

The CSS:

<style>

 .fake-table{display:table;width:100%;height:100%;}
 .left-size{width:30%;height:100%;}
 .left-size{width:70%;height:100%;}

</style>

DataTables: Cannot read property style of undefined

The solution is pretty simple.

_x000D_
_x000D_
  <table id="TASK_LIST_GRID" class="table table-striped table-bordered table-hover dataTable no-footer" width="100%" role="grid" aria-describedby="TASK_LIST_GRID_info">_x000D_
  <thead>_x000D_
    <tr role="row">_x000D_
      <th class="sorting" tabindex="0" aria-controls="TASK_LIST_GRID" rowspan="1" colspan="1">Solution</th>_x000D_
      <th class="sorting" tabindex="0" aria-controls="TASK_LIST_GRID" rowspan="1" colspan="1">Status</th>_x000D_
      <th class="sorting" tabindex="0" aria-controls="TASK_LIST_GRID" rowspan="1" colspan="1">Category</th>_x000D_
      <th class="sorting" tabindex="0" aria-controls="TASK_LIST_GRID" rowspan="1" colspan="1">Type</th>_x000D_
      <th class="sorting" tabindex="0" aria-controls="TASK_LIST_GRID" rowspan="1" colspan="1">Due Date</th>_x000D_
      <th class="sorting" tabindex="0" aria-controls="TASK_LIST_GRID" rowspan="1" colspan="1">Create Date</th>_x000D_
      <th class="sorting" tabindex="0" aria-controls="TASK_LIST_GRID" rowspan="1" colspan="1">Owner</th>_x000D_
      <th class="sorting" tabindex="0" aria-controls="TASK_LIST_GRID" rowspan="1" colspan="1">Comments</th>_x000D_
      <th class="sorting" tabindex="0" aria-controls="TASK_LIST_GRID" rowspan="1" colspan="1">Mnemonic</th>_x000D_
      <th class="sorting" tabindex="0" aria-controls="TASK_LIST_GRID" rowspan="1" colspan="1">Domain</th>_x000D_
      <th class="sorting" tabindex="0" aria-controls="TASK_LIST_GRID" rowspan="1" colspan="1">Approve</th>_x000D_
      <th class="sorting" tabindex="0" aria-controls="TASK_LIST_GRID" rowspan="1" colspan="1">Dismiss</th>_x000D_
    </tr>_x000D_
  </thead>_x000D_
  <tbody></tbody>_x000D_
</table>
_x000D_
_x000D_
_x000D_

_x000D_
_x000D_
                TASKLISTGRID = $("#TASK_LIST_GRID").DataTable({_x000D_
                    data : response,_x000D_
                    columns : columns.AdoptionTaskInfo.columns,_x000D_
                    paging: true_x000D_
                });_x000D_
                _x000D_
                //Note: columns : columns.AdoptionTaskInfo.columns has at least a column not definded in the <thead>
_x000D_
_x000D_
_x000D_

Note: columns : columns.AdoptionTaskInfo.columns has at least a column not defined in the table head

The simplest way to resize an UIImage?

For Swift 5:

extension UIImage {
  func resized(to newSize: CGSize) -> UIImage? {
    UIGraphicsBeginImageContextWithOptions(newSize, false, 0)
    defer { UIGraphicsEndImageContext() }

    draw(in: CGRect(origin: .zero, size: newSize))
    return UIGraphicsGetImageFromCurrentImageContext()
  }
}

How to get the URL without any parameters in JavaScript?

I'm LATE to the party, but I had to solve this recently, figured I'd share the wealth.

const url = window.location.origin + window.location.pathname
//http://example.com/somedir/somefile/

window.location.origin will give you the base url, in our test case: http://example.com

window.location.pathname will give you the route path (after the base url), in our test case /somedir/somefile

SOLUTION 2

You can simply do the following to get rid of the query parameters.

const url = window.location.href.split('?')[0]

What is the curl error 52 "empty reply from server"?

In my case (curl 7.47.0), it is because I set the header content-length on curl command manually with a value which is calculated by postman (I used postman to generate curl command parameters and copy them to shell). After I delete header content-length, it works normally.

How can I store JavaScript variable output into a PHP variable?

You have to remember that if JS and PHP live in the same document, the PHP will be executed first (at the server) and the JS will be executed second (at the browser)--and the two will NEVER interact (excepting where you output JS with PHP, which is not really an interaction between the two engines).

With that in mind, the closest you could come is to use a PHP variable in your JS:

<?php
$a = 'foo'; // $a now holds PHP string foo
?>
<script>
    var a = '<?php echo $a; ?>'; //outputting string foo in context of JS
                                 //must wrap in quotes so that it is still string foo when JS does execute
                                 //when this DOES execute in the browser, PHP will have already completed all processing and exited
</script>
<?php
//do something else with $a
//JS still hasn't executed at this point
?>

As I stated, in this scenario the PHP (ALL of it) executes FIRST at the server, causing:

  1. a PHP variable $a to be created as string 'foo'
  2. the value of $a to be outputted in context of some JavaScript (which is not currently executing)
  3. more done with PHP's $a
  4. all output, including the JS with the var assignment, is sent to the browser.

As written, this results in the following being sent to the browser for execution (I removed the JS comments for clarity):

<script>
    var a = 'foo';
</script>

Then, and only then, will the JS start executing with its own variable a set to "foo" (at which point PHP is out of the picture).

In other words, if the two live in the same document and no extra interaction with the server is performed, JS can NOT cause any effect in PHP. Furthermore, PHP is limited in its effect on JS to the simple ability to output some JS or something in context of JS.

Sending a mail from a linux shell script

If both exim and ssmtp are running, you may enter into troubles. So if you just want to run a simple MTA, just to have a simple smtp client to send email notifications for insistance, you shall purge the eventually preinstalled MTA like exim or postfix first and reinstall ssmtp.

Then it's quite straight forward, configuring only 2 files (revaliases and ssmtp.conf) - See ssmtp doc - , and usage in your bash or bourne script is like :

#!/bin/sh  
SUBJECT=$1  
RECEIVER=$2  
TEXT=$3  

SERVER_NAME=$HOSTNAME  
SENDER=$(whoami)  
USER="noreply"

[[ -z $1 ]] && SUBJECT="Notification from $SENDER on server $SERVER_NAME"  
[[ -z $2 ]] && RECEIVER="another_configured_email_address"   
[[ -z $3 ]] && TEXT="no text content"  

MAIL_TXT="Subject: $SUBJECT\nFrom: $SENDER\nTo: $RECEIVER\n\n$TEXT"  
echo -e $MAIL_TXT | sendmail -t  
exit $?  

Obviously do not forget to open your firewall output to the smtp port (25).

Docker CE on RHEL - Requires: container-selinux >= 2.9

I was getting the same error Requires: container-selinux >= 2.9 on amazon ec2 instance(Rhel7)

I tried to add extra package rmp repo by executing sudo yum-config-manager --enable rhui-REGION-rhel-server-extras
but it works. followed steps from https://installdocker.blogspot.com/ and I was able to install docker.

Exiting out of a FOR loop in a batch file?

Did a little research on this, it appears that you are looping from 1 to 2147483647, in increments of 1.

(1, 1, 2147483647): The firs number is the starting number, the next number is the step, and the last number is the end number.

Edited To Add

It appears that the loop runs to completion regardless of any test conditions. I tested

FOR /L %%F IN (1, 1, 5) DO SET %%F=6

And it ran very quickly.

Second Edit

Since this is the only line in the batch file, you might try the EXIT command:

FOR /L %%F IN (1, 1, 2147483647) DO @IF NOT EXIST %%F EXIT

However, this will also close the DOS prompt window.

Seconds CountDown Timer

int segundo = 0;
DateTime dt = new DateTime();

private void timer1_Tick(object sender, EventArgs e){
    segundo++;
    label1.Text = dt.AddSeconds(segundo).ToString("HH:mm:ss");
}

The specified child already has a parent. You must call removeView() on the child's parent first

In my case I was accidentally returning a child view from within Layout.onCreateView() as shown below:

public View onCreateView(LayoutInflater inflater, ViewGroup container, Bundle savedInstanceState) {
    View view = inflater.inflate(R.layout.fragment_reject, container, false);

    Button button = view.findViewById(R.id.some_button);

    return button; // <-- Problem is this
}

The solution was to return the parent view instead of the child view.

Connect to SQL Server database from Node.js

There is a module on npm called mssqlhelper

You can install it to your project by npm i mssqlhelper

Example of connecting and performing a query:

var db = require('./index');

db.config({
    host: '192.168.1.100'
    ,port: 1433
    ,userName: 'sa'
    ,password: '123'
    ,database:'testdb'
});

db.query(
    'select @Param1 Param1,@Param2 Param2'
    ,{
         Param1: { type : 'NVarChar', size: 7,value : 'myvalue' }
         ,Param2: { type : 'Int',value : 321 }
    }
    ,function(res){
        if(res.err)throw new Error('database error:'+res.err.msg);
        var rows = res.tables[0].rows;
        for (var i = 0; i < rows.length; i++) {
            console.log(rows[i].getValue(0),rows[i].getValue('Param2'));
        }
    }
);

You can read more about it here: https://github.com/play175/mssqlhelper

:o)

Use of 'prototype' vs. 'this' in JavaScript?

The first example changes the interface for that object only. The second example changes the interface for all object of that class.

How to get the selected item of a combo box to a string variable in c#

Try this:

string selected = this.ComboBox.GetItemText(this.ComboBox.SelectedItem);
MessageBox.Show(selected);

How to copy selected files from Android with adb pull

You can move your files to other folder and then pull whole folder.

adb shell mkdir /sdcard/tmp
adb shell mv /sdcard/mydir/*.jpg /sdcard/tmp # move your jpegs to temporary dir
adb pull /sdcard/tmp/ # pull this directory (be sure to put '/' in the end)
adb shell mv /sdcard/tmp/* /sdcard/mydir/ # move them back
adb shell rmdir /sdcard/tmp # remove temporary directory

How can I execute a python script from an html button?

This would require knowledge of a backend website language.

Fortunately, Python's Flask Library is a suitable backend language for the project at hand.

Check out this answer from another thread.

Summarizing multiple columns with dplyr?

All the examples are great, but I figure I'd add one more to show how working in a "tidy" format simplifies things. Right now the data frame is in "wide" format meaning the variables "a" through "d" are represented in columns. To get to a "tidy" (or long) format, you can use gather() from the tidyr package which shifts the variables in columns "a" through "d" into rows. Then you use the group_by() and summarize() functions to get the mean of each group. If you want to present the data in a wide format, just tack on an additional call to the spread() function.


library(tidyverse)

# Create reproducible df
set.seed(101)
df <- tibble(a   = sample(1:5, 10, replace=T), 
             b   = sample(1:5, 10, replace=T), 
             c   = sample(1:5, 10, replace=T), 
             d   = sample(1:5, 10, replace=T), 
             grp = sample(1:3, 10, replace=T))

# Convert to tidy format using gather
df %>%
    gather(key = variable, value = value, a:d) %>%
    group_by(grp, variable) %>%
    summarize(mean = mean(value)) %>%
    spread(variable, mean)
#> Source: local data frame [3 x 5]
#> Groups: grp [3]
#> 
#>     grp        a     b        c        d
#> * <int>    <dbl> <dbl>    <dbl>    <dbl>
#> 1     1 3.000000   3.5 3.250000 3.250000
#> 2     2 1.666667   4.0 4.666667 2.666667
#> 3     3 3.333333   3.0 2.333333 2.333333

Practical uses for the "internal" keyword in C#

A very interesting use of internal - with internal member of course being limited only to the assembly in which it is declared - is getting "friend" functionality to some degree out of it. A friend member is something that is visible only to certain other assemblies outside of the assembly in which its declared. C# has no built in support for friend, however the CLR does.

You can use InternalsVisibleToAttribute to declare a friend assembly, and all references from within the friend assembly will treat the internal members of your declaring assembly as public within the scope of the friend assembly. A problem with this is that all internal members are visible; you cannot pick and choose.

A good use for InternalsVisibleTo is to expose various internal members to a unit test assembly thus eliminating the needs for complex reflection work arounds to test those members. All internal members being visible isn't so much of a problem, however taking this approach does muck up your class interfaces pretty heavily and can potentially ruin encapsulation within the declaring assembly.

How to enable scrolling of content inside a modal?

Actually for Bootstrap 3 you also need to override the .modal-open class on body.

    body.modal-open, 
    .modal-open 
    .navbar-fixed-top, 
    .modal-open 
    .navbar-fixed-bottom {
     margin-right: 15px; /*<-- to margin-right: 0px;*/
    }

How to execute a .bat file from a C# windows form app?

Here is what you are looking for:

Service hangs up at WaitForExit after calling batch file

It's about a question as to why a service can't execute a file, but it shows all the code necessary to do so.

How to add an action to a UIAlertView button using Swift iOS

See my code:

 @IBAction func foundclicked(sender: AnyObject) {

            if (amountTF.text.isEmpty)
            {
                let alert = UIAlertView(title: "Oops! Empty Field", message: "Please enter the amount", delegate: nil, cancelButtonTitle: "OK")

                alert.show()
            }

            else {

            var alertController = UIAlertController(title: "Confirm Bid Amount", message: "Final Bid Amount : "+amountTF.text , preferredStyle: .Alert)
            var okAction = UIAlertAction(title: "Confirm", style: UIAlertActionStyle.Default) {
                UIAlertAction in

                JHProgressHUD.sharedHUD.loaderColor = UIColor.redColor()
                        JHProgressHUD.sharedHUD.showInView(self.view, withHeader: "Amount registering" , andFooter: "Loading")
                }
            var cancelAction = UIAlertAction(title: "Cancel", style: UIAlertActionStyle.Cancel) {
                UIAlertAction in

                alertController .removeFromParentViewController()
            }
                            alertController.addAction(okAction)
                            alertController.addAction(cancelAction)

                self.presentViewController(alertController, animated: true, completion: nil)

            }

        }

How to download image using requests

This is the first response that comes up for google searches on how to download a binary file with requests. In case you need to download an arbitrary file with requests, you can use:

import requests
url = 'https://s3.amazonaws.com/lab-data-collections/GoogleNews-vectors-negative300.bin.gz'
open('GoogleNews-vectors-negative300.bin.gz', 'wb').write(requests.get(url, allow_redirects=True).content)

printf format specifiers for uint32_t and size_t

Try

#include <inttypes.h>
...

printf("i [ %zu ] k [ %"PRIu32" ]\n", i, k);

The z represents an integer of length same as size_t, and the PRIu32 macro, defined in the C99 header inttypes.h, represents an unsigned 32-bit integer.

Multiple dex files define Landroid/support/v4/accessibilityservice/AccessibilityServiceInfoCompat

I had the same problem, and my solution is changing the support version '27.+'(27.1.0) to '27.0.1'

Branch from a previous commit using Git

git checkout -b <branch-name> <sha1-of-commit>

Current user in Magento?

Have a look at the helper class: Mage_Customer_Helper_Data

To simply get the customer name, you can write the following code:-

$customerName = Mage::helper('customer')->getCustomerName();

For more information about the customer's entity id, website id, email, etc. you can use getCustomer function. The following code shows what you can get from it:-

echo "<pre>"; print_r(Mage::helper('customer')->getCustomer()->getData()); echo "</pre>";

From the helper class, you can also get information about customer login url, register url, logout url, etc.

From the isLoggedIn function in the helper class, you can also check whether a customer is logged in or not.

[] and {} vs list() and dict(), which is better?

list() and [] work differently:

>>> def a(p):
...     print(id(p))
... 
>>> for r in range(3):
...     a([])
... 
139969725291904
139969725291904
139969725291904
>>> for r in range(3):
...     a(list())
... 
139969725367296
139969725367552
139969725367616

list() always create new object in heap, but [] can reuse memory cell in many reason.

Running a cron job at 2:30 AM everyday

As an addition to the all above mentioned great answers, check the https://crontab.guru/ - a useful online resource for checking your crontab syntax.

What you get is human readable representation of what you have specified.

See the examples below:

Laravel 5.2 - pluck() method returns array

In Laravel 5.1+, you can use the value() instead of pluck.

To get first occurence, You can either use

DB::table('users')->value('name');

or use,

DB::table('users')->where('id', 1)->pluck('name')->first();

What is the best way to auto-generate INSERT statements for a SQL Server table?

I used this script which I have put on my blog (How-to generate Insert statement procedures on sql server).

So far has worked for me, although they might be bugs I have not discovered yet .

How to make a div have a fixed size?

Thats the natural behavior of the buttons. You could try putting a max-width/max-height on the parent container, but I'm not sure if that would do it.

max-width:something px;
max-height:something px;

The other option would be to use the devlopr tools and see if you can remove the natural padding.

padding: 0;

Java String to Date object of the format "yyyy-mm-dd HH:mm:ss"

Your not applying Date formator. rather you are just parsing the date. to get output in this format

yyyy-MM-dd HH:mm:ss.SSSSSS

we have to use format() method here is full example:- Here is full example:- it will take Date in this format yyyy-MM-dd HH:mm:ss.SSSSSS and as result we will get output as same as this format yyyy-MM-dd HH:mm:ss.SSSSSS

 import java.text.ParseException;
import java.text.SimpleDateFormat;
import java.util.Date;

//TODO OutPut should LIKE in this format yyyy-MM-dd HH:mm:ss.SSSSSS.
public class TestDateExample {

public static void main(String args[]) throws ParseException {

    SimpleDateFormat changeFormat = new SimpleDateFormat("yyyy-MM-dd HH:mm:ss.SSSSSS");

    java.util.Date temp = changeFormat.parse("2012-07-10 14:58:00.000000");
     Date thisDate = changeFormat.parse("2012-07-10 14:58:00.000000");  
    System.out.println(thisDate);
    System.out.println("----------------------------"); 
    System.out.println("After applying formating :");
    String strDateOutput = changeFormat.format(temp);
    System.out.println(strDateOutput);

}

}

Working example screen

No log4j2 configuration file found. Using default configuration: logging only errors to the console

I use hive jdbc in a java maven project and have the same issues.

My method is to add a log4j2.xml file under src/main/java/resources

import org.slf4j.Logger;
import org.slf4j.LoggerFactory;

public class MyClassName {
    private static final Logger LOG = LoggerFactory.getLogger(MyClassName.class);
}

log4j2.xml

<?xml version="1.0" encoding="UTF-8"?>
<Configuration status="WARN">
    <Appenders>
        <Console name="Console" target="SYSTEM_OUT">
            <PatternLayout pattern="%d{HH:mm:ss.SSS} [%t] %-5level %logger{36} - %msg%n"/>
        </Console>
    </Appenders>
    <Loggers>
        <Logger name="<your_package_name>.<your_class_name>" level="debug">
        <AppenderRef ref="Console"/>
        </Logger>
        <Root level="WARN">
            <AppenderRef ref="Console"/>
        </Root>
    </Loggers>
</Configuration>

How would I find the second largest salary from the employee table?

Simple Answer:

SELECT distinct(sal)
FROM emp
ORDER BY sal DESC
LIMIT 1, 1;

You will get only the second max salary.

And if you need any 3rd or 4th or Nth value you can increase the first value followed by LIMIT (n-1) ie. for 4th salary : LIMIT 3, 1;

What are all the user accounts for IIS/ASP.NET and how do they differ?

This is a very good question and sadly many developers don't ask enough questions about IIS/ASP.NET security in the context of being a web developer and setting up IIS. So here goes....

To cover the identities listed:

IIS_IUSRS:

This is analogous to the old IIS6 IIS_WPG group. It's a built-in group with it's security configured such that any member of this group can act as an application pool identity.

IUSR:

This account is analogous to the old IUSR_<MACHINE_NAME> local account that was the default anonymous user for IIS5 and IIS6 websites (i.e. the one configured via the Directory Security tab of a site's properties).

For more information about IIS_IUSRS and IUSR see:

Understanding Built-In User and Group Accounts in IIS 7

DefaultAppPool:

If an application pool is configured to run using the Application Pool Identity feature then a "synthesised" account called IIS AppPool\<pool name> will be created on the fly to used as the pool identity. In this case there will be a synthesised account called IIS AppPool\DefaultAppPool created for the life time of the pool. If you delete the pool then this account will no longer exist. When applying permissions to files and folders these must be added using IIS AppPool\<pool name>. You also won't see these pool accounts in your computers User Manager. See the following for more information:

Application Pool Identities

ASP.NET v4.0: -

This will be the Application Pool Identity for the ASP.NET v4.0 Application Pool. See DefaultAppPool above.

NETWORK SERVICE: -

The NETWORK SERVICE account is a built-in identity introduced on Windows 2003. NETWORK SERVICE is a low privileged account under which you can run your application pools and websites. A website running in a Windows 2003 pool can still impersonate the site's anonymous account (IUSR_ or whatever you configured as the anonymous identity).

In ASP.NET prior to Windows 2008 you could have ASP.NET execute requests under the Application Pool account (usually NETWORK SERVICE). Alternatively you could configure ASP.NET to impersonate the site's anonymous account via the <identity impersonate="true" /> setting in web.config file locally (if that setting is locked then it would need to be done by an admin in the machine.config file).

Setting <identity impersonate="true"> is common in shared hosting environments where shared application pools are used (in conjunction with partial trust settings to prevent unwinding of the impersonated account).

In IIS7.x/ASP.NET impersonation control is now configured via the Authentication configuration feature of a site. So you can configure to run as the pool identity, IUSR or a specific custom anonymous account.

LOCAL SERVICE:

The LOCAL SERVICE account is a built-in account used by the service control manager. It has a minimum set of privileges on the local computer. It has a fairly limited scope of use:

LocalService Account

LOCAL SYSTEM:

You didn't ask about this one but I'm adding for completeness. This is a local built-in account. It has fairly extensive privileges and trust. You should never configure a website or application pool to run under this identity.

LocalSystem Account

In Practice:

In practice the preferred approach to securing a website (if the site gets its own application pool - which is the default for a new site in IIS7's MMC) is to run under Application Pool Identity. This means setting the site's Identity in its Application Pool's Advanced Settings to Application Pool Identity:

enter image description here

In the website you should then configure the Authentication feature:

enter image description here

Right click and edit the Anonymous Authentication entry:

enter image description here

Ensure that "Application pool identity" is selected:

enter image description here

When you come to apply file and folder permissions you grant the Application Pool identity whatever rights are required. For example if you are granting the application pool identity for the ASP.NET v4.0 pool permissions then you can either do this via Explorer:

enter image description here

Click the "Check Names" button:

enter image description here

Or you can do this using the ICACLS.EXE utility:

icacls c:\wwwroot\mysite /grant "IIS AppPool\ASP.NET v4.0":(CI)(OI)(M)

...or...if you site's application pool is called BobsCatPicBlogthen:

icacls c:\wwwroot\mysite /grant "IIS AppPool\BobsCatPicBlog":(CI)(OI)(M)

I hope this helps clear things up.

Update:

I just bumped into this excellent answer from 2009 which contains a bunch of useful information, well worth a read:

The difference between the 'Local System' account and the 'Network Service' account?

Detect Scroll Up & Scroll down in ListView

My solution works perfectly giving the exact value for each scroll direction. distanceFromFirstCellToTop contains the exact distance from the first cell to the top of the parent View. I save this value in previousDistanceFromFirstCellToTop and as I scroll I compare it with the new value. If it's lower then I scrolled up, else, I scrolled down.

private int previousDistanceFromFirstCellToTop;

listview.setOnScrollListener(new OnScrollListener() {

    @Override
    public void onScrollStateChanged(AbsListView view, int scrollState) {

    }

    @Override
    public void onScroll(AbsListView view, int firstVisibleItem, int visibleItemCount, int totalItemCount) {
        View firstCell = listview.getChildAt(0);
        int distanceFromFirstCellToTop = listview.getFirstVisiblePosition() * firstCell.getHeight() - firstCell.getTop();

        if(distanceFromFirstCellToTop < previousDistanceFromFirstCellToTop)
        {
           //Scroll Up
        }
        else if(distanceFromFirstCellToTop  > previousDistanceFromFirstCellToTop)
        {
           //Scroll Down
        }
        previousDistanceFromFirstCellToTop = distanceFromFirstCellToTop;
    }
});

For Xamarin developers, the solution is the following:

Note: don't forget to run on UI thread

listView.Scroll += (o, e) =>
{
    View firstCell = listView.GetChildAt(0);
    int distanceFromFirstCellToTop = listView.FirstVisiblePosition * firstCell.Height - firstCell.Top;

    if (distanceFromFirstCellToTop < previousDistanceFromFirstCellToTop)
    {
        //Scroll Up
    }
    else if (distanceFromFirstCellToTop > previousDistanceFromFirstCellToTop)
    {
        //Scroll Down
    }
    previousDistanceFromFirstCellToTop = distanceFromFirstCellToTop;
};

How to extract week number in sql

After converting your varchar2 date to a true date datatype, then convert back to varchar2 with the desired mask:

to_char(to_date('01/02/2012','MM/DD/YYYY'),'WW')

If you want the week number in a number datatype, you can wrap the statement in to_number():

to_number(to_char(to_date('01/02/2012','MM/DD/YYYY'),'WW'))

However, you have several week number options to consider:

WW  Week of year (1-53) where week 1 starts on the first day of the year and continues to the seventh day of the year.
W   Week of month (1-5) where week 1 starts on the first day of the month and ends on the seventh.
IW  Week of year (1-52 or 1-53) based on the ISO standard.

how do I get eclipse to use a different compiler version for Java?

From the menu bar: Project -> Properties -> Java Compiler

Enable project specific settings (checked) Uncheck "use Compliance from execution environment '.... Select the desired "compiler compliance level"

That will allow you to compile "1.5" code using a "1.6" JDK.

If you want to acutally use a 1.5 JDK to produce "1.5" compliant code, then install a suitable 1.5 JDK and tell eclipse where it is installed via:

Window -> preferences -> Installed JREs

And then go back to your project

Project -> properties -> Java Build Path -> libraries

remove the 1.6 system libaries, and: add library... -> JRE System LIbrary -> Alternate JRE -> The JRE you want.

Verify that the correct JRE is on the project's build path, save everything, and enjoy!