Programs & Examples On #Itil

ITIL (formerly the shortcut for Information Technology Infrastructure Library) is a management framework aiming to aligning IT services with the needs of business using 26 core processes which are described in 5 core volumes. Since 2013 it is a trademark of AXELOS.

FragmentActivity to Fragment

first of all;

a Fragment must be inside a FragmentActivity, that's the first rule,

a FragmentActivity is quite similar to a standart Activity that you already know, besides having some Fragment oriented methods

second thing about Fragments, is that there is one important method you MUST call, wich is onCreateView, where you inflate your layout, think of it as the setContentLayout

here is an example:

    @Override public View onCreateView(LayoutInflater inflater, ViewGroup container, Bundle savedInstanceState) {     mView       = inflater.inflate(R.layout.fragment_layout, container, false);       return mView; } 

and continu your work based on that mView, so to find a View by id, call mView.findViewById(..);


for the FragmentActivity part:

the xml part "must" have a FrameLayout in order to inflate a fragment in it

        <FrameLayout             android:id="@+id/content_frame"             android:layout_width="match_parent"             android:layout_height="match_parent"  >         </FrameLayout> 

as for the inflation part

getSupportFragmentManager().beginTransaction().replace(R.id.content_frame, new YOUR_FRAGMENT, "TAG").commit();


begin with these, as there is tons of other stuf you must know about fragments and fragment activities, start of by reading something about it (like life cycle) at the android developer site

IOException: read failed, socket might closed - Bluetooth on Android 4.3

I have finally found a workaround. The magic is hidden under the hood of the BluetoothDevice class (see https://github.com/android/platform_frameworks_base/blob/android-4.3_r2/core/java/android/bluetooth/BluetoothDevice.java#L1037).

Now, when I receive that exception, I instantiate a fallback BluetoothSocket, similar to the source code below. As you can see, invoking the hidden method createRfcommSocket via reflections. I have no clue why this method is hidden. The source code defines it as public though...

Class<?> clazz = tmp.getRemoteDevice().getClass();
Class<?>[] paramTypes = new Class<?>[] {Integer.TYPE};

Method m = clazz.getMethod("createRfcommSocket", paramTypes);
Object[] params = new Object[] {Integer.valueOf(1)};

fallbackSocket = (BluetoothSocket) m.invoke(tmp.getRemoteDevice(), params);
fallbackSocket.connect();

connect() then does not fail any longer. I have experienced a few issues still. Basically, this sometimes blocks and fails. Rebooting the SPP-Device (plug off / plug in) helps in such cases. Sometimes I also get another Pairing request after connect() even when the device is already bonded.

UPDATE:

here is a complete class, containing some nested classes. for a real implementation these could be held as seperate classes.

import java.io.IOException;
import java.io.InputStream;
import java.io.OutputStream;
import java.lang.reflect.Method;
import java.util.List;
import java.util.UUID;

import android.bluetooth.BluetoothAdapter;
import android.bluetooth.BluetoothDevice;
import android.bluetooth.BluetoothSocket;
import android.util.Log;

public class BluetoothConnector {

    private BluetoothSocketWrapper bluetoothSocket;
    private BluetoothDevice device;
    private boolean secure;
    private BluetoothAdapter adapter;
    private List<UUID> uuidCandidates;
    private int candidate;


    /**
     * @param device the device
     * @param secure if connection should be done via a secure socket
     * @param adapter the Android BT adapter
     * @param uuidCandidates a list of UUIDs. if null or empty, the Serial PP id is used
     */
    public BluetoothConnector(BluetoothDevice device, boolean secure, BluetoothAdapter adapter,
            List<UUID> uuidCandidates) {
        this.device = device;
        this.secure = secure;
        this.adapter = adapter;
        this.uuidCandidates = uuidCandidates;

        if (this.uuidCandidates == null || this.uuidCandidates.isEmpty()) {
            this.uuidCandidates = new ArrayList<UUID>();
            this.uuidCandidates.add(UUID.fromString("00001101-0000-1000-8000-00805F9B34FB"));
        }
    }

    public BluetoothSocketWrapper connect() throws IOException {
        boolean success = false;
        while (selectSocket()) {
            adapter.cancelDiscovery();

            try {
                bluetoothSocket.connect();
                success = true;
                break;
            } catch (IOException e) {
                //try the fallback
                try {
                    bluetoothSocket = new FallbackBluetoothSocket(bluetoothSocket.getUnderlyingSocket());
                    Thread.sleep(500);                  
                    bluetoothSocket.connect();
                    success = true;
                    break;  
                } catch (FallbackException e1) {
                    Log.w("BT", "Could not initialize FallbackBluetoothSocket classes.", e);
                } catch (InterruptedException e1) {
                    Log.w("BT", e1.getMessage(), e1);
                } catch (IOException e1) {
                    Log.w("BT", "Fallback failed. Cancelling.", e1);
                }
            }
        }

        if (!success) {
            throw new IOException("Could not connect to device: "+ device.getAddress());
        }

        return bluetoothSocket;
    }

    private boolean selectSocket() throws IOException {
        if (candidate >= uuidCandidates.size()) {
            return false;
        }

        BluetoothSocket tmp;
        UUID uuid = uuidCandidates.get(candidate++);

        Log.i("BT", "Attempting to connect to Protocol: "+ uuid);
        if (secure) {
            tmp = device.createRfcommSocketToServiceRecord(uuid);
        } else {
            tmp = device.createInsecureRfcommSocketToServiceRecord(uuid);
        }
        bluetoothSocket = new NativeBluetoothSocket(tmp);

        return true;
    }

    public static interface BluetoothSocketWrapper {

        InputStream getInputStream() throws IOException;

        OutputStream getOutputStream() throws IOException;

        String getRemoteDeviceName();

        void connect() throws IOException;

        String getRemoteDeviceAddress();

        void close() throws IOException;

        BluetoothSocket getUnderlyingSocket();

    }


    public static class NativeBluetoothSocket implements BluetoothSocketWrapper {

        private BluetoothSocket socket;

        public NativeBluetoothSocket(BluetoothSocket tmp) {
            this.socket = tmp;
        }

        @Override
        public InputStream getInputStream() throws IOException {
            return socket.getInputStream();
        }

        @Override
        public OutputStream getOutputStream() throws IOException {
            return socket.getOutputStream();
        }

        @Override
        public String getRemoteDeviceName() {
            return socket.getRemoteDevice().getName();
        }

        @Override
        public void connect() throws IOException {
            socket.connect();
        }

        @Override
        public String getRemoteDeviceAddress() {
            return socket.getRemoteDevice().getAddress();
        }

        @Override
        public void close() throws IOException {
            socket.close();
        }

        @Override
        public BluetoothSocket getUnderlyingSocket() {
            return socket;
        }

    }

    public class FallbackBluetoothSocket extends NativeBluetoothSocket {

        private BluetoothSocket fallbackSocket;

        public FallbackBluetoothSocket(BluetoothSocket tmp) throws FallbackException {
            super(tmp);
            try
            {
              Class<?> clazz = tmp.getRemoteDevice().getClass();
              Class<?>[] paramTypes = new Class<?>[] {Integer.TYPE};
              Method m = clazz.getMethod("createRfcommSocket", paramTypes);
              Object[] params = new Object[] {Integer.valueOf(1)};
              fallbackSocket = (BluetoothSocket) m.invoke(tmp.getRemoteDevice(), params);
            }
            catch (Exception e)
            {
                throw new FallbackException(e);
            }
        }

        @Override
        public InputStream getInputStream() throws IOException {
            return fallbackSocket.getInputStream();
        }

        @Override
        public OutputStream getOutputStream() throws IOException {
            return fallbackSocket.getOutputStream();
        }


        @Override
        public void connect() throws IOException {
            fallbackSocket.connect();
        }


        @Override
        public void close() throws IOException {
            fallbackSocket.close();
        }

    }

    public static class FallbackException extends Exception {

        /**
         * 
         */
        private static final long serialVersionUID = 1L;

        public FallbackException(Exception e) {
            super(e);
        }

    }
}

Proper way to initialize a C# dictionary with values?

Object initializers were introduced in C# 3.0, check which framework version you are targeting.

Overview of C# 3.0

Breaking out of a for loop in Java

You can use:

for (int x = 0; x < 10; x++) {
  if (x == 5) { // If x is 5, then break it.
    break;
  }
}

Setting Action Bar title and subtitle

There is another option that no one commented, from the Support Library V7 was implemented by Google ActionBarSupport, which is compatible ActionBar from Android 2.2 to the last.
If you change your ActionBar this you can do getSupportActionBar().setTitle("") on all Android versions.

Undefined reference to 'vtable for xxx'

GNU linker, in my case companion of GCC 8.1.0, well detects not re-declared pure virtual methods, but above certain complexity of class design it fails to identify missing implementation of methods and answers with a flat "V-Table Missing",

or even tends to report missing implementation, in spite it is there.

The only solution then is to verify consistency of declaration of implementation manually, method by method.

Could not resolve Spring property placeholder

It's definitely not a problem with propeties file not being found, since in that case another exception is thrown.

Make sure that you actually have a value with key idm.url in your idm.properties.

In Visual Studio C++, what are the memory allocation representations?

This link has more information:

https://en.wikipedia.org/wiki/Magic_number_(programming)#Debug_values

* 0xABABABAB : Used by Microsoft's HeapAlloc() to mark "no man's land" guard bytes after allocated heap memory
* 0xABADCAFE : A startup to this value to initialize all free memory to catch errant pointers
* 0xBAADF00D : Used by Microsoft's LocalAlloc(LMEM_FIXED) to mark uninitialised allocated heap memory
* 0xBADCAB1E : Error Code returned to the Microsoft eVC debugger when connection is severed to the debugger
* 0xBEEFCACE : Used by Microsoft .NET as a magic number in resource files
* 0xCCCCCCCC : Used by Microsoft's C++ debugging runtime library to mark uninitialised stack memory
* 0xCDCDCDCD : Used by Microsoft's C++ debugging runtime library to mark uninitialised heap memory
* 0xDDDDDDDD : Used by Microsoft's C++ debugging heap to mark freed heap memory
* 0xDEADDEAD : A Microsoft Windows STOP Error code used when the user manually initiates the crash.
* 0xFDFDFDFD : Used by Microsoft's C++ debugging heap to mark "no man's land" guard bytes before and after allocated heap memory
* 0xFEEEFEEE : Used by Microsoft's HeapFree() to mark freed heap memory

Go install fails with error: no install location for directory xxx outside GOPATH

I'm on Windows, and I got it by giving command go help gopath to cmd, and read the bold text in the instruction,

that is if code you wnat to install is at ..BaseDir...\SomeProject\src\basic\set, the GOPATH should not be the same location as code, it should be just Base Project DIR: ..BaseDir...\SomeProject.

The GOPATH environment variable lists places to look for Go code. On Unix, the value is a colon-separated string. On Windows, the value is a semicolon-separated string. On Plan 9, the value is a list.

If the environment variable is unset, GOPATH defaults to a subdirectory named "go" in the user's home directory ($HOME/go on Unix, %USERPROFILE%\go on Windows), unless that directory holds a Go distribution. Run "go env GOPATH" to see the current GOPATH.

See https://golang.org/wiki/SettingGOPATH to set a custom GOPATH.

Each directory listed in GOPATH must have a prescribed structure:

The src directory holds source code. The path below src determines the import path or executable name.

The pkg directory holds installed package objects. As in the Go tree, each target operating system and architecture pair has its own subdirectory of pkg (pkg/GOOS_GOARCH).

If DIR is a directory listed in the GOPATH, a package with source in DIR/src/foo/bar can be imported as "foo/bar" and has its compiled form installed to "DIR/pkg/GOOS_GOARCH/foo/bar.a".

The bin directory holds compiled commands. Each command is named for its source directory, but only the final element, not the entire path. That is, the command with source in DIR/src/foo/quux is installed into DIR/bin/quux, not DIR/bin/foo/quux. The "foo/" prefix is stripped so that you can add DIR/bin to your PATH to get at the installed commands. If the GOBIN environment variable is set, commands are installed to the directory it names instead of DIR/bin. GOBIN must be an absolute path.

Here's an example directory layout:

GOPATH=/home/user/go

/home/user/go/
    src/
        foo/
            bar/               (go code in package bar)
                x.go
            quux/              (go code in package main)
                y.go
    bin/
        quux                   (installed command)
    pkg/
        linux_amd64/
            foo/
                bar.a          (installed package object)

..........

if GOPATH has been set to Base Project DIR and still has this problem, in windows you can try to set GOBIN as Base Project DIR\bin or %GOPATH%\bin.

In python, how do I cast a class object to a dict

something like this would probably work

class MyClass:
    def __init__(self,x,y,z):
       self.x = x
       self.y = y
       self.z = z
    def __iter__(self): #overridding this to return tuples of (key,value)
       return iter([('x',self.x),('y',self.y),('z',self.z)])

dict(MyClass(5,6,7)) # because dict knows how to deal with tuples of (key,value)

When is null or undefined used in JavaScript?

I find that some of these answers are vague and complicated, I find the best way to figure out these things for sure is to just open up the console and test it yourself.

var x;

x == null            // true
x == undefined       // true
x === null           // false
x === undefined      // true

var y = null;

y == null            // true
y == undefined       // true
y === null           // true
y === undefined      // false

typeof x             // 'undefined'
typeof y             // 'object'

var z = {abc: null};

z.abc == null        // true
z.abc == undefined   // true
z.abc === null       // true
z.abc === undefined  // false

z.xyz == null        // true
z.xyz == undefined   // true
z.xyz === null       // false
z.xyz === undefined  // true

null = 1;            // throws error: invalid left hand assignment
undefined = 1;       // works fine: this can cause some problems

So this is definitely one of the more subtle nuances of JavaScript. As you can see, you can override the value of undefined, making it somewhat unreliable compared to null. Using the == operator, you can reliably use null and undefined interchangeably as far as I can tell. However, because of the advantage that null cannot be redefined, I might would use it when using ==.

For example, variable != null will ALWAYS return false if variable is equal to either null or undefined, whereas variable != undefined will return false if variable is equal to either null or undefined UNLESS undefined is reassigned beforehand.

You can reliably use the === operator to differentiate between undefined and null, if you need to make sure that a value is actually undefined (rather than null).

According to the ECMAScript 5 spec:

  • Both Null and Undefined are two of the six built in types.

4.3.9 undefined value

primitive value used when a variable has not been assigned a value

4.3.11 null value

primitive value that represents the intentional absence of any object value

google console error `OR-IEH-01`

Recently I was also having this issue, then I contacted Google Support and they gave me this link to provide required info, I posted and within 24 hours my problem was fixed.

Link: https://support.google.com/payments/contact/alt_account_verification

"code ." Not working in Command Line for Visual Studio Code on OSX/Mac

I've tried install add code command to PATH with Visual Studio Code's command pannel, but it's disabled after restart bash. if you want it be consolidated, just create a code file in your PATH; I create a code file in usr/local/bin and add

#!/usr/bin/env bash
function realpath() { python -c "import os,sys;print(os.path.realpath(sys.argv[1]))" "$0"; }
CONTENTS="/Applications/Visual Studio Code.app/Contents"
ELECTRON="$CONTENTS/MacOS/Electron"
CLI="$CONTENTS/Resources/app/out/cli.js"
ELECTRON_RUN_AS_NODE=1 "$ELECTRON" "$CLI" "$@"
exit $?

just replace this CONTENTS with your VS Code's installed path. and don't forget make it excuteable with chmod +x /usr/local/bin/code

Git: "Not currently on any branch." Is there an easy way to get back on a branch, while keeping the changes?

I know I told babay in 2012 that I thought it was unlikely that someone wouldn't realize that they weren't on a branch and commit. This just happened to me, so I guess I have to admit that I was wrong, but considering that it took until 2016 for this to happen to me, you could argue that it is in fact unlikely.

Anyway, creating a new branch is overkill in my opinion. All you have to do is:

git checkout some-branch
git merge commit-sha

If you didn't copy the commit-sha before checking out the other branch, you can easily find it by running:

git reflog

How can I generate Javadoc comments in Eclipse?

At a place where you want javadoc, type in /**<NEWLINE> and it will create the template.

SQL Server r2 installation error .. update Visual Studio 2008 to SP1

Finally, I solved it. Even though the solution is a bit lengthy, I think its the simplest. The solution is as follows:

  1. Install Visual Studio 2008
  2. Install the service Package 1 (SP1)
  3. Install SQL Server 2008 r2

TreeMap sort by value

import java.util.*;

public class Main {

public static void main(String[] args) {
    TreeMap<String, Integer> initTree = new TreeMap();
    initTree.put("D", 0);
    initTree.put("C", -3);
    initTree.put("A", 43);
    initTree.put("B", 32);
    System.out.println("Sorted by keys:");
    System.out.println(initTree);
    List list = new ArrayList(initTree.entrySet());
    Collections.sort(list, new Comparator<Map.Entry<String, Integer>>() {
        @Override
        public int compare(Map.Entry<String, Integer> e1, Map.Entry<String, Integer> e2) {
            return e1.getValue().compareTo(e2.getValue());
        }
    });
    System.out.println("Sorted by values:");
    System.out.println(list);
}
}

Best way to implement keyboard shortcuts in a Windows Forms application?

You can even try this example:

public class MDIParent : System.Windows.Forms.Form
{
    public bool NextTab()
    {
         // some code
    }

    public bool PreviousTab()
    {
         // some code
    }

    protected override bool ProcessCmdKey(ref Message message, Keys keys)
    {
        switch (keys)
        {
            case Keys.Control | Keys.Tab:
              {
                NextTab();
                return true;
              }
            case Keys.Control | Keys.Shift | Keys.Tab:
              {
                PreviousTab();
                return true;
              }
        }
        return base.ProcessCmdKey(ref message, keys);
    }
}

public class mySecondForm : System.Windows.Forms.Form
{
    // some code...
}

How to remove all debug logging calls before building the release version of an Android app?

the simplest way;

use DebugLog

All logs are disabled by DebugLog when the app is released.

https://github.com/MustafaFerhan/DebugLog

Best way to store password in database

The best security practice is not to store the password at all (not even encrypted), but to store the salted hash (with a unique salt per password) of the encrypted password.

That way it is (practically) impossible to retrieve a plaintext password.

How do I convert a pandas Series or index to a Numpy array?

A more recent way to do this is to use the .to_numpy() function.

If I have a dataframe with a column 'price', I can convert it as follows:

priceArray = df['price'].to_numpy()

You can also pass the data type, such as float or object, as an argument of the function

Can a normal Class implement multiple interfaces?

Of course... Almost all classes implements several interfaces. On any page of java documentation on Oracle you have a subsection named "All implemented interfaces".

Here an example of the Date class.

How to get the indexpath.row when an element is activated?

Solution:

You have a button (myButton) or any other view in cell. Assign tag in cellForRowAt like this

cell.myButton.tag = indexPath.row

Now in you tapFunction or any other. Fetch it out like this and save it in a local variable.

currentCellNumber = (sender.view?.tag)!

After this you can use anywhere this currentCellNumber to get the indexPath.row of selected button.

Enjoy!

How do I dump the data of some SQLite3 tables?

In Python or Java or any high level language the .dump does not work. We need to code the conversion to CSV by hand. I give an Python example. Others, examples would be appreciated:

from os import path   
import csv 

def convert_to_csv(directory, db_name):
    conn = sqlite3.connect(path.join(directory, db_name + '.db'))
    cursor = conn.cursor()
    cursor.execute("SELECT name FROM sqlite_master WHERE type='table';")
    tables = cursor.fetchall()
    for table in tables:
        table = table[0]
        cursor.execute('SELECT * FROM ' + table)
        column_names = [column_name[0] for column_name in cursor.description]
        with open(path.join(directory, table + '.csv'), 'w') as csv_file:
            csv_writer = csv.writer(csv_file)
            csv_writer.writerow(column_names)
            while True:
                try:
                    csv_writer.writerow(cursor.fetchone())
                except csv.Error:
                    break

If you have 'panel data, in other words many individual entries with id's add this to the with look and it also dumps summary statistics:

        if 'id' in column_names:
            with open(path.join(directory, table + '_aggregate.csv'), 'w') as csv_file:
                csv_writer = csv.writer(csv_file)
                column_names.remove('id')
                column_names.remove('round')
                sum_string = ','.join('sum(%s)' % item for item in column_names)
                cursor.execute('SELECT round, ' + sum_string +' FROM ' + table + ' GROUP BY round;')
                csv_writer.writerow(['round'] + column_names)
                while True:
                    try:
                        csv_writer.writerow(cursor.fetchone())
                    except csv.Error:
                        break 

Is it possible to run one logrotate check manually?

logrotate -d [your_config_file] invokes debug mode, giving you a verbose description of what would happen, but leaving the log files untouched.

How do I compare two Integers?

I just encountered this in my code and it took me a while to figure it out. I was doing an intersection of two sorted lists and was only getting small numbers in my output. I could get it to work by using (x - y == 0) instead of (x == y) during comparison.

How to beautify JSON in Python?

You could pipe the output to jq. If you python script contains something like

print json.dumps(data)

then you can fire:

python foo.py | jq '.'

How to escape regular expression special characters using javascript?

Use the backslash to escape a character. For example:

/\\d/

This will match \d instead of a numeric character

How do I access call log for android?

Use Below code:

private void getCallDeatils() {
    StringBuffer stringBuffer = new StringBuffer();
    Cursor managedCursor = getActivity().managedQuery(CallLog.Calls.CONTENT_URI, null, null, null, null);
    int number = managedCursor.getColumnIndex(CallLog.Calls.NUMBER);
    int type = managedCursor.getColumnIndex(CallLog.Calls.TYPE);
    int date = managedCursor.getColumnIndex(CallLog.Calls.DATE);

    int duration = managedCursor.getColumnIndex(CallLog.Calls.DURATION);
    stringBuffer.append("Call Deatils");
    while (managedCursor.moveToNext()) {
        String phNumber = managedCursor.getString(number);
        String callType = managedCursor.getString(type);
        String callDate = managedCursor.getString(date);
        Date callDayTime = new Date(Long.valueOf(callDate));
        DateFormat df = new SimpleDateFormat("MM/dd/yyyy HH:mm:ss");
        String reportDate = df.format(callDayTime);
        String callDuration = managedCursor.getString(duration);
        String dir = null;
        int dircode = Integer.parseInt(callType);
        switch (dircode) {
            case CallLog.Calls.OUTGOING_TYPE:
                dir = "OUTGOING";
                break;

            case CallLog.Calls.INCOMING_TYPE:
                dir = "INCOMING";

                break;

            case CallLog.Calls.MISSED_TYPE:
                dir = "MISSED";
                break;

        }
        stringBuffer.append("\nPhone Number:--- " + phNumber + " \nCall Type:--- " + dir + " \nCall Date:--- " +callDate + " \nCall duration in sec :--- " + callDuration);
        stringBuffer.append("\n----------------------------------");

        logs.add(new LogClass(phNumber,dir,reportDate,callDuration));




    }

ORA-00054: resource busy and acquire with NOWAIT specified or timeout expired

I also face the similar Issue. Nothing programmer has to do to resolve this error. I informed to my oracle DBA team. They kill the session and worked like a charm.

Adding CSRFToken to Ajax request

If you are working in node.js with lusca try also this:

$.ajax({
url: "http://test.com",
type:"post"
headers: {'X-CSRF-Token': $('meta[name="csrf-token"]').attr('content')}
})

How to check if a process is running via a batch script

I don't know how to do so with built in CMD but if you have grep you can try the following:

tasklist /FI "IMAGENAME eq myApp.exe" | grep myApp.exe
if ERRORLEVEL 1 echo "myApp is not running"

Determine what user created objects in SQL Server

If you need a small and specific mechanism, you can search for DLL Triggers info.

JavaScript module pattern with example

I would really recommend anyone entering this subject to read Addy Osmani's free book:

"Learning JavaScript Design Patterns".

http://addyosmani.com/resources/essentialjsdesignpatterns/book/

This book helped me out immensely when I was starting into writing more maintainable JavaScript and I still use it as a reference. Have a look at his different module pattern implementations, he explains them really well.

Email validation using jQuery

Bug is in Jquery Validation Validation Plugin Only validates with @ to change this

change the code to this

email: function( value, element ) {
    // From http://www.whatwg.org/specs/web-apps/current-work/multipage/states-of-the-type-attribute.html#e-mail-state-%28type=email%29
    // Retrieved 2014-01-14
    // If you have a problem with this implementation, report a bug against the above spec
    // Or use custom methods to implement your own email validation
    return this.optional( element ) || /^([a-zA-Z0-9_\.\-])+\@(([a-zA-Z0-9\-])+\.)+([a-zA-Z0-9]{2,4})+$/.test( value );
}

batch script - read line by line

For those with spaces in the path, you are going to want something like this: n.b. It expands out to an absolute path, rather than relative, so if your running directory path has spaces in, these count too.

set SOURCE=path\with spaces\to\my.log
FOR /F "usebackq delims=" %%A IN ("%SOURCE%") DO (
    ECHO %%A
)

To explain:

(path\with spaces\to\my.log)

Will not parse, because spaces. If it becomes:

("path\with spaces\to\my.log")

It will be handled as a string rather than a file path.

"usebackq delims=" 

See docs will allow the path to be used as a path (thanks to Stephan).

Returning data from Axios API

axiosTest() is firing asynchronously and not being waited for.

A then() function needs to be hooked up afterwards in order to capture the response variable (axiosTestData).

See Promise for more info.

See Async to level up.

_x000D_
_x000D_
// Dummy Url._x000D_
const url = 'https://jsonplaceholder.typicode.com/posts/1'_x000D_
_x000D_
// Axios Test._x000D_
const axiosTest = axios.get_x000D_
_x000D_
// Axios Test Data._x000D_
axiosTest(url).then(function(axiosTestResult) {_x000D_
  console.log('response.JSON:', {_x000D_
    message: 'Request received',_x000D_
    data: axiosTestResult.data_x000D_
  })_x000D_
})
_x000D_
<script src="https://cdnjs.cloudflare.com/ajax/libs/axios/0.18.0/axios.js"></script>
_x000D_
_x000D_
_x000D_

download csv file from web api in angular js

Workable solution:

downloadCSV(data){   
 const newBlob = new Blob([decodeURIComponent(encodeURI(data))], { type: 'text/csv;charset=utf-8;' });

        // IE doesn't allow using a blob object directly as link href
        // instead it is necessary to use msSaveOrOpenBlob
        if (window.navigator && window.navigator.msSaveOrOpenBlob) {
          window.navigator.msSaveOrOpenBlob(newBlob);
          return;
        }

        // For other browsers:
        // Create a link pointing to the ObjectURL containing the blob.
        const fileData = window.URL.createObjectURL(newBlob);

        const link = document.createElement('a');
        link.href = fileData;
        link.download = `Usecase-Unprocessed.csv`;
        // this is necessary as link.click() does not work on the latest firefox
        link.dispatchEvent(new MouseEvent('click', { bubbles: true, cancelable: true, view: window }));

        setTimeout(function () {
          // For Firefox it is necessary to delay revoking the ObjectURL
          window.URL.revokeObjectURL(fileData);
          link.remove();
        }, 5000);
  }

CSS background-image not working

Add "display:block;" in your .btn-pTool class

How to check that a string is parseable to a double?

Google's Guava library provides a nice helper method to do this: Doubles.tryParse(String). You use it like Double.parseDouble but it returns null rather than throwing an exception if the string does not parse to a double.

Change image onmouseover

here's a native javascript inline code to change image onmouseover & onmouseout:

<a href="#" id="name">
    <img title="Hello" src="/ico/view.png" onmouseover="this.src='/ico/view.hover.png'" onmouseout="this.src='/ico/view.png'" />
</a>

CSV parsing in Java - working example..?

At a minimum you are going to need to know the column delimiter.

Add days Oracle SQL

Some disadvantage of "INTERVAL '1' DAY" is that bind variables cannot be used for the number of days added. Instead, numtodsinterval can be used, like in this small example:

select trunc(sysdate) + numtodsinterval(:x, 'day') tag
from dual

See also: NUMTODSINTERVAL in Oracle Database Online Documentation

PHP Composer behind http proxy

on Windows insert:

set http_proxy=<proxy>
set https_proxy=<proxy>

before

php "%~dp0composer.phar" %*

or on Linux insert:

export http_proxy=<proxy>
export https_proxy=<proxy>

before

php "${dir}/composer.phar" "$@"

Does it make sense to use Require.js with Angular.js?

Here is the approach I use: http://thaiat.github.io/blog/2014/02/26/angularjs-and-requirejs-for-very-large-applications/

The page shows a possible implementation of AngularJS + RequireJS, where the code is split by features and then component type.

Create auto-numbering on images/figures in MS Word

Office 2007

Right click the figure, select Insert Caption, Select Numbering, check box next to 'Include chapter number', select OK, Select OK again, then you figure identifier should be updated.

Forbidden You don't have permission to access /wp-login.php on this server

I had this same problem, and after temporarily deleting all my .htaccess files, then trying to modify them as suggested, and making sure all my files and folder permissions were set to 777, I still couldn't get it to work. I don't know why I couldn't access the file, but I was able to create a new file and access it no problem. So what I did was create a new file in /wp-admin/ called temp.php and pasted all the code from install.php into it. This allowed me to access the file. The only other thing I had to do was edit the code so that the form submitted to temp.php instead of install.php. After that, I could finish the install and everything worked.

<form id="setup" method="post" action="temp.php?step=2">

SimpleDateFormat returns 24-hour date: how to get 12-hour date?

I re-encounter this in the hard way as well. H vs h, for 24-hour vs 12 hour !

How do I find all of the symlinks in a directory tree?

What I do is create a script in my bin directory that is like an alias. For example I have a script named lsd ls -l | grep ^d

you could make one lsl ls -lR | grep ^l

Just chmod them +x and you are good to go.

Where does Visual Studio look for C++ header files?

Visual Studio looks for headers in this order:

  • In the current source directory.
  • In the Additional Include Directories in the project properties (Project -> [project name] Properties, under C/C++ | General).
  • In the Visual Studio C++ Include directories under Tools ? Options ? Projects and Solutions ? VC++ Directories.
  • In new versions of Visual Studio (2015+) the above option is deprecated and a list of default include directories is available at Project Properties ? Configuration ? VC++ Directories

In your case, add the directory that the header is to the project properties (Project Properties ? Configuration ? C/C++ ? General ? Additional Include Directories).

How to add a JAR in NetBeans

Project Files Services Tabls

go files tabs

drag drop file to libs files hover.

return project tabs and what are you see :)

How to strip a specific word from a string?

If want to remove the word from only the start of the string, then you could do:

  string[string.startswith(prefix) and len(prefix):]  

Where string is your string variable and prefix is the prefix you want to remove from your string variable.

For example:

  >>> papa = "papa is a good man. papa is the best."  
  >>> prefix = 'papa'
  >>> papa[papa.startswith(prefix) and len(prefix):]
  ' is a good man. papa is the best.'

Read an Excel file directly from a R script

library(RODBC)
file.name <- "file.xls"
sheet.name <- "Sheet Name"

## Connect to Excel File Pull and Format Data
excel.connect <- odbcConnectExcel(file.name)
dat <- sqlFetch(excel.connect, sheet.name, na.strings=c("","-"))
odbcClose(excel.connect)

Personally, I like RODBC and can recommend it.

Giving UIView rounded corners

Try this

#import <QuartzCore/QuartzCore.h> // not necessary for 10 years now  :)

...

view.layer.cornerRadius = 5;
view.layer.masksToBounds = true;

Note: If you are trying to apply rounded corners to a UIViewController's view, it should not be applied in the view controller's constructor, but rather in -viewDidLoad, after view is actually instantiated.

SQL Server : check if variable is Empty or NULL for WHERE clause

Just use

If @searchType is null means 'return the whole table' then use

WHERE p.[Type] = @SearchType OR @SearchType is NULL

If @searchType is an empty string means 'return the whole table' then use

WHERE p.[Type] = @SearchType OR @SearchType = ''

If @searchType is null or an empty string means 'return the whole table' then use

WHERE p.[Type] = @SearchType OR Coalesce(@SearchType,'') = ''

Finding version of Microsoft C++ compiler from command-line (for makefiles)

Try:

cl /v

Actually, any time I give cl an argument, it prints out the version number on the first line.

You could just feed it a garbage argument and then parse the first line of the output, which contains the verison number.

Best way to read a large file into a byte array in C#?

Depending on the frequency of operations, the size of the files, and the number of files you're looking at, there are other performance issues to take into consideration. One thing to remember, is that each of your byte arrays will be released at the mercy of the garbage collector. If you're not caching any of that data, you could end up creating a lot of garbage and be losing most of your performance to % Time in GC. If the chunks are larger than 85K, you'll be allocating to the Large Object Heap(LOH) which will require a collection of all generations to free up (this is very expensive, and on a server will stop all execution while it's going on). Additionally, if you have a ton of objects on the LOH, you can end up with LOH fragmentation (the LOH is never compacted) which leads to poor performance and out of memory exceptions. You can recycle the process once you hit a certain point, but I don't know if that's a best practice.

The point is, you should consider the full life cycle of your app before necessarily just reading all the bytes into memory the fastest way possible or you might be trading short term performance for overall performance.

How do I draw a grid onto a plot in Python?

Using rcParams you can show grid very easily as follows

plt.rcParams['axes.facecolor'] = 'white'
plt.rcParams['axes.edgecolor'] = 'white'
plt.rcParams['axes.grid'] = True
plt.rcParams['grid.alpha'] = 1
plt.rcParams['grid.color'] = "#cccccc"

If grid is not showing even after changing these parameters then use

plt.grid(True)

before calling

plt.show()

How do I kill the process currently using a port on localhost in Windows?

For use in command line:

for /f "tokens=5" %a in ('netstat -aon ^| find ":8080" ^| find "LISTENING"') do taskkill /f /pid %a

For use in bat-file:

for /f "tokens=5" %%a in ('netstat -aon ^| find ":8080" ^| find "LISTENING"') do taskkill /f /pid %%a

how to get all child list from Firebase android

DatabaseReference mRootRef = FirebaseDatabase.getInstance().getReference();
        DatabaseReference mMainMenuRef = mRootRef.child("tut_master");//main
        DatabaseReference mSubMenuRef = mMainMenuRef.child("english");//sub
        List<Tutorial>   tutorialNames=new ArrayList<>();
        mSubMenuRef.addValueEventListener(new ValueEventListener() {
            @Override
            public void onDataChange(DataSnapshot dataSnapshot) {

                for(DataSnapshot ds : dataSnapshot.getChildren()) {
                    long id = ds.child("id").getValue(Long.class);
                    String name = ds.child("name").getValue(String.class);

                    Tutorial tut = new Tutorial();
                    tut.setTutId(id+"");
                    tut.setTutName(name);
                    tutList.add(tut);

                }

            }

            @Override
            public void onCancelled(@NonNull DatabaseError databaseError) {

            }


        });

How do you extract IP addresses from files using a regex in a linux shell?

You can use some shell helper I made: https://github.com/philpraxis/ipextract

included them here for convenience:

#!/bin/sh
ipextract () 
{ 
egrep --only-matching -E  '(25[0-5]|2[0-4][0-9]|[01]?[0-9][0-9]?)\.(25[0-5]|2[0-4][0-9]|[01]?[0-9][0-9]?)\.(25[0-5]|2[0-4][0-9]|[01]?[0-9][0-9]?)\.(25[0-5]|2[0-4][0-9]|[01]?[0-9][0-9]?)' 
}

ipextractnet ()
{ 
egrep --only-matching -E  '(25[0-5]|2[0-4][0-9]|[01]?[0-9][0-9]?)\.(25[0-5]|2[0-4][0-9]|[01]?[0-9][0-9]?)\.(25[0-5]|2[0-4][0-9]|[01]?[0-9][0-9]?)\.(25[0-5]|2[0-4][0-9]|[01]?[0-9][0-9]?)/[[:digit:]]+' 
}

ipextracttcp ()
{ 
egrep --only-matching -E  '[[:digit:]]+/tcp' 
}

ipextractudp ()
{ 
egrep --only-matching -E  '[[:digit:]]+/udp' 
}

ipextractsctp ()
{ 
egrep --only-matching -E  '[[:digit:]]+/sctp' 
}

ipextractfqdn ()
{ 
egrep --only-matching -E  '[a-zA-Z0-9]+[a-zA-Z0-9\-\.]*\.[a-zA-Z]{2,}' 
}

Load it / source it (when stored in ipextract file) from shell:

$ . ipextract

Use them:

$ ipextract < /etc/hosts
127.0.0.1
255.255.255.255
$

For some example of real use:

ipextractfqdn < /var/log/snort/alert | sort -u
dmesg | ipextractudp

C# generics syntax for multiple type parameter constraints

void foo<TOne, TTwo>() 
   where TOne : BaseOne
   where TTwo : BaseTwo

More info here:
http://msdn.microsoft.com/en-us/library/d5x73970.aspx

JVM property -Dfile.encoding=UTF8 or UTF-8?

It will be:

UTF8

See here for the definitions.

window.onload vs $(document).ready()

A word of caution on using $(document).ready() with Internet Explorer. If an HTTP request is interrupted before the entire document is loaded (for example, while a page is streaming to the browser, another link is clicked) IE will trigger the $(document).ready event.

If any code within the $(document).ready() event references DOM objects, the potential exists for those objects to be not found, and Javascript errors can occur. Either guard your references to those objects, or defer code which references those objects to the window.load event.

I have not been able to reproduce this problem in other browsers (specifically, Chrome and Firefox)

File to byte[] in Java

Basically you have to read it in memory. Open the file, allocate the array, and read the contents from the file into the array.

The simplest way is something similar to this:

public byte[] read(File file) throws IOException, FileTooBigException {
    if (file.length() > MAX_FILE_SIZE) {
        throw new FileTooBigException(file);
    }
    ByteArrayOutputStream ous = null;
    InputStream ios = null;
    try {
        byte[] buffer = new byte[4096];
        ous = new ByteArrayOutputStream();
        ios = new FileInputStream(file);
        int read = 0;
        while ((read = ios.read(buffer)) != -1) {
            ous.write(buffer, 0, read);
        }
    }finally {
        try {
            if (ous != null)
                ous.close();
        } catch (IOException e) {
        }

        try {
            if (ios != null)
                ios.close();
        } catch (IOException e) {
        }
    }
    return ous.toByteArray();
}

This has some unnecessary copying of the file content (actually the data is copied three times: from file to buffer, from buffer to ByteArrayOutputStream, from ByteArrayOutputStream to the actual resulting array).

You also need to make sure you read in memory only files up to a certain size (this is usually application dependent) :-).

You also need to treat the IOException outside the function.

Another way is this:

public byte[] read(File file) throws IOException, FileTooBigException {
    if (file.length() > MAX_FILE_SIZE) {
        throw new FileTooBigException(file);
    }

    byte[] buffer = new byte[(int) file.length()];
    InputStream ios = null;
    try {
        ios = new FileInputStream(file);
        if (ios.read(buffer) == -1) {
            throw new IOException(
                    "EOF reached while trying to read the whole file");
        }
    } finally {
        try {
            if (ios != null)
                ios.close();
        } catch (IOException e) {
        }
    }
    return buffer;
}

This has no unnecessary copying.

FileTooBigException is a custom application exception. The MAX_FILE_SIZE constant is an application parameters.

For big files you should probably think a stream processing algorithm or use memory mapping (see java.nio).

<img>: Unsafe value used in a resource URL context

It is possible to set image as background image to avoid unsafe url error:

<div [style.backgroundImage]="'url(' + imageUrl + ')'" class="show-image"></div>

CSS:

.show-image {
    width: 100px;
    height: 100px;
    border-radius: 50%;
    background-size: cover;        
}

How to avoid .pyc files?

You can set sys.dont_write_bytecode = True in your source, but that would have to be in the first python file loaded. If you execute python somefile.py then you will not get somefile.pyc.

When you install a utility using setup.py and entry_points= you will have set sys.dont_write_bytecode in the startup script. So you cannot rely on the "default" startup script generated by setuptools.

If you start Python with python file as argument yourself you can specify -B:

python -B somefile.py

somefile.pyc would not be generated anyway, but no .pyc files for other files imported too.

If you have some utility myutil and you cannot change that, it will not pass -B to the python interpreter. Just start it by setting the environment variable PYTHONDONTWRITEBYTECODE:

PYTHONDONTWRITEBYTECODE=x myutil

Get ID from URL with jQuery

var full_url = document.URL; // Get current url
var url_array = full_url.split('/') // Split the string into an array with / as separator
var last_segment = url_array[url_array.length-1];  // Get the last part of the array (-1)
alert( last_segment ); // Alert last segment

How can I pass an Integer class correctly by reference?

There are two problems:

  1. Integer is pass by value, not by reference. Changing the reference inside a method won't be reflected into the passed-in reference in the calling method.
  2. Integer is immutable. There's no such method like Integer#set(i). You could otherwise just make use of it.

To get it to work, you need to reassign the return value of the inc() method.

integer = inc(integer);

To learn a bit more about passing by value, here's another example:

public static void main(String... args) {
    String[] strings = new String[] { "foo", "bar" };
    changeReference(strings);
    System.out.println(Arrays.toString(strings)); // still [foo, bar]
    changeValue(strings);
    System.out.println(Arrays.toString(strings)); // [foo, foo]
}
public static void changeReference(String[] strings) {
    strings = new String[] { "foo", "foo" };
}
public static void changeValue(String[] strings) {
    strings[1] = "foo";
}

Twitter bootstrap scrollable table

None of these answers worked satisfactorily for me. They either didn't fix the table heading row in place or they required fixed column widths to work, and even then tended to have the heading row and body rows misaligned in various browsers.

I recommend biting the bullet and using a proper grid control like jsGrid or my personal favorite, SlickGrid. It obviously introduces a dependency but if you want your tables to behave like real grids with cross-browser support, this will save you pulling your hair out. It also gives you the option of sorting and resizing columns plus tons of other features if you want them.

XAMPP, Apache - Error: Apache shutdown unexpectedly

For me, world wide web publishing-service was using port 80. I killed this by running the following command on cmd:

net stop http

After that, XAMPP ran Apache without any problems.

How to make PyCharm always show line numbers

For version 4.0, 4.5 on Windows

File -> Settings

Then,

Editor -> General -> Appearance -> Show line numbers

For version 4.0 on Mac OSX

PyCharm-->Preferences

Then,

Editor-->General-->Appearance-->checkbox: "Show line numbers"

Using RegEX To Prefix And Append In Notepad++

Assuming alphanumeric words, you can use:

Search  = ^([A-Za-z0-9]+)$
Replace = able:"\1"

Or, if you just want to highlight the lines and use "Replace All" & "In Selection" (with the same replace):

Search = ^(.+)$

^ points to the start of the line.
$ points to the end of the line.

\1 will be the source match within the parentheses.

Pass values of checkBox to controller action in asp.net mvc4

For the MVC Controller method, use a nullable boolean type:

public ActionResult Index( string responsables, bool? checkResp) { etc. }

Then if the check box is checked, checkResp will be true. If not, it will be null.

How can I get a precise time, for example in milliseconds in Objective-C?

I would NOT use mach_absolute_time() because it queries a combination of the kernel and the processor for an absolute time using ticks (probably an uptime).

What I would use:

CFAbsoluteTimeGetCurrent();

This function is optimized to correct the difference in the iOS and OSX software and hardware.

Something Geekier

The quotient of a difference in mach_absolute_time() and AFAbsoluteTimeGetCurrent() is always around 24000011.154871

Here is a log of my app:

Please note that final result time is a difference in CFAbsoluteTimeGetCurrent()'s

 2012-03-19 21:46:35.609 Rest Counter[3776:707] First Time: 353900795.609040
 2012-03-19 21:46:36.360 Rest Counter[3776:707] Second Time: 353900796.360177
 2012-03-19 21:46:36.361 Rest Counter[3776:707] Final Result Time (difference): 0.751137
 2012-03-19 21:46:36.363 Rest Counter[3776:707] Mach absolute time: 18027372
 2012-03-19 21:46:36.365 Rest Counter[3776:707] Mach absolute time/final time: 24000113.153295
 2012-03-19 21:46:36.367 Rest Counter[3776:707] -----------------------------------------------------
 2012-03-19 21:46:43.074 Rest Counter[3776:707] First Time: 353900803.074637
 2012-03-19 21:46:43.170 Rest Counter[3776:707] Second Time: 353900803.170256
 2012-03-19 21:46:43.172 Rest Counter[3776:707] Final Result Time (difference): 0.095619
 2012-03-19 21:46:43.173 Rest Counter[3776:707] Mach absolute time: 2294833
 2012-03-19 21:46:43.175 Rest Counter[3776:707] Mach absolute time/final time: 23999753.727777
 2012-03-19 21:46:43.177 Rest Counter[3776:707] -----------------------------------------------------
 2012-03-19 21:46:46.499 Rest Counter[3776:707] First Time: 353900806.499199
 2012-03-19 21:46:55.017 Rest Counter[3776:707] Second Time: 353900815.016985
 2012-03-19 21:46:55.018 Rest Counter[3776:707] Final Result Time (difference): 8.517786
 2012-03-19 21:46:55.020 Rest Counter[3776:707] Mach absolute time: 204426836
 2012-03-19 21:46:55.022 Rest Counter[3776:707] Mach absolute time/final time: 23999996.639500
 2012-03-19 21:46:55.024 Rest Counter[3776:707] -----------------------------------------------------

Leave only two decimal places after the dot

Using the property of String

double value = 123.456789;
String.Format("{0:0.00}", value);

Note: This can be used to display only.

Using System.Math

double value = 123.456789;
System.Math.Round(value, 2);

c++ "Incomplete type not allowed" error accessing class reference information (Circular dependency with forward declaration)

Player.cpp require the definition of Ball class. So simply add #include "Ball.h"

Player.cpp:

#include "Player.h"
#include "Ball.h"

void Player::doSomething(Ball& ball) {
    ball.ballPosX += 10;                   // incomplete type error occurs here.
}

Hadoop cluster setup - java.net.ConnectException: Connection refused

Make sure HDFS is online. Start it by $HADOOP_HOME/sbin/start-dfs.sh Once you do that, your test with telnet localhost 9001should work.

Get values from an object in JavaScript

I am sorry that your concluding question is not that clear but you are wrong from the very first line. The variable data is an Object not an Array

To access the attributes of an object is pretty easy:

alert(data.second);

But, if this does not completely answer your question, please clarify it and post back.

Thanks !

Best way to access web camera in Java

I think the project you are looking for is: https://github.com/sarxos/webcam-capture (I'm the author)

There is an example working exactly as you've described - after it's run, the window appear where, after you press "Start" button, you can see live image from webcam device and save it to file after you click on "Snapshot" (source code available, please note that FPS counter in the corner can be disabled):

snapshot

The project is portable (WinXP, Win7, Win8, Linux, Mac, Raspberry Pi) and does not require any additional software to be installed on the PC.

API is really nice and easy to learn. Example how to capture single image and save it to PNG file:

Webcam webcam = Webcam.getDefault();
webcam.open();
ImageIO.write(webcam.getImage(), "PNG", new File("test.png"));

Difference between "module.exports" and "exports" in the CommonJs Module System

Also, one things that may help to understand:

math.js

this.add = function (a, b) {
    return a + b;
};

client.js

var math = require('./math');
console.log(math.add(2,2); // 4;

Great, in this case:

console.log(this === module.exports); // true
console.log(this === exports); // true
console.log(module.exports === exports); // true

Thus, by default, "this" is actually equals to module.exports.

However, if you change your implementation to:

math.js

var add = function (a, b) {
    return a + b;
};

module.exports = {
    add: add
};

In this case, it will work fine, however, "this" is not equal to module.exports anymore, because a new object was created.

console.log(this === module.exports); // false
console.log(this === exports); // true
console.log(module.exports === exports); // false

And now, what will be returned by the require is what was defined inside the module.exports, not this or exports, anymore.

Another way to do it would be:

math.js

module.exports.add = function (a, b) {
    return a + b;
};

Or:

math.js

exports.add = function (a, b) {
    return a + b;
};

What is difference between sjlj vs dwarf vs seh?

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

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

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

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

GCC GNU about Exception Handling:

GCC supports two methods for exception handling (EH):

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

[...]

Structured Exception Handling (SEH)

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

See also:

How to clear the Entry widget after a button is pressed in Tkinter?

You shall proceed with ent.delete(0,"end") instead of using 'END', use 'end' inside quotation.

 secret = randrange(1,100)
print(secret)
def res(real, secret):
    if secret==eval(real):
        showinfo(message='that is right!')
    real.delete(0, END)

def guess():
    ge = Tk()
    ge.title('guessing game')

    Label(ge, text="what is your guess:").pack(side=TOP)

    ent = Entry(ge)
    ent.pack(side=TOP)

    btn=Button(ge, text="Enter", command=lambda: res(ent.get(),secret))
    btn.pack(side=LEFT)

    ge.mainloop()

This shall solve your problem

What is the reason for the error message "System cannot find the path specified"?

There is not only 1 %SystemRoot%\System32 on Windows x64. There are 2 such directories.

The real %SystemRoot%\System32 directory is for 64-bit applications. This directory contains a 64-bit cmd.exe.

But there is also %SystemRoot%\SysWOW64 for 32-bit applications. This directory is used if a 32-bit application accesses %SystemRoot%\System32. It contains a 32-bit cmd.exe.

32-bit applications can access %SystemRoot%\System32 for 64-bit applications by using the alias %SystemRoot%\Sysnative in path.

For more details see the Microsoft documentation about File System Redirector.

So the subdirectory run was created either in %SystemRoot%\System32 for 64-bit applications and 32-bit cmd is run for which this directory does not exist because there is no subdirectory run in %SystemRoot%\SysWOW64 which is %SystemRoot%\System32 for 32-bit cmd.exe or the subdirectory run was created in %SystemRoot%\System32 for 32-bit applications and 64-bit cmd is run for which this directory does not exist because there is no subdirectory run in %SystemRoot%\System32 as this subdirectory exists only in %SystemRoot%\SysWOW64.

The following code could be used at top of the batch file in case of subdirectory run is in %SystemRoot%\System32 for 64-bit applications:

@echo off
set "SystemPath=%SystemRoot%\System32"
if not "%ProgramFiles(x86)%" == "" if exist %SystemRoot%\Sysnative\* set "SystemPath=%SystemRoot%\Sysnative"

Every console application in System32\run directory must be executed with %SystemPath% in the batch file, for example %SystemPath%\run\YourApp.exe.

How it works?

There is no environment variable ProgramFiles(x86) on Windows x86 and therefore there is really only one %SystemRoot%\System32 as defined at top.

But there is defined the environment variable ProgramFiles(x86) with a value on Windows x64. So it is additionally checked on Windows x64 if there are files in %SystemRoot%\Sysnative. In this case the batch file is processed currently by 32-bit cmd.exe and only in this case %SystemRoot%\Sysnative needs to be used at all. Otherwise %SystemRoot%\System32 can be used also on Windows x64 as when the batch file is processed by 64-bit cmd.exe, this is the directory containing the 64-bit console applications (and the subdirectory run).

Note: %SystemRoot%\Sysnative is not a directory! It is not possible to cd to %SystemRoot%\Sysnative or use if exist %SystemRoot%\Sysnative or if exist %SystemRoot%\Sysnative\. It is a special alias existing only for 32-bit executables and therefore it is necessary to check if one or more files exist on using this path by using if exist %SystemRoot%\Sysnative\cmd.exe or more general if exist %SystemRoot%\Sysnative\*.

Serialize an object to string

Serialize and Deserialize (XML/JSON):

public static T XmlDeserialize<T>(this string toDeserialize)
{
    XmlSerializer xmlSerializer = new XmlSerializer(typeof(T));
    using(StringReader textReader = new StringReader(toDeserialize))
    {      
        return (T)xmlSerializer.Deserialize(textReader);
    }
}

public static string XmlSerialize<T>(this T toSerialize)
{
    XmlSerializer xmlSerializer = new XmlSerializer(typeof(T));
    using(StringWriter textWriter = new StringWriter())
    {
        xmlSerializer.Serialize(textWriter, toSerialize);
        return textWriter.ToString();
    }
}

public static T JsonDeserialize<T>(this string toDeserialize)
{
    return JsonConvert.DeserializeObject<T>(toDeserialize);
}

public static string JsonSerialize<T>(this T toSerialize)
{
    return JsonConvert.SerializeObject(toSerialize);
}

Eclipse, regular expression search and replace

At least at STS (SpringSource Tool Suite) groups are numbered starting form 0, so replace string will be

replace: ((TypeName)$0)

How to make HTML input tag only accept numerical values?

You can also use the pattern attribute in html5:

<input type="text" name="name" pattern="[0-9]" title="Title" /> 

Input validation tutorial

Although, if your doctype isn't html then I think you'll need to use some javascript/jquery.

CSS fill remaining width

I did a quick experiment after looking at a number of potential solutions all over the place. This is what I ended up with:

http://jsbin.com/hapelawake

Markdown `native` text alignment

The div element has its own alignment attribute, align.

<div align="center">
  my text here.
</div>

Difference between an API and SDK

I'm not sure there's any official definition of these two terms. I understand an API to be a set of documented programmable libraries and supporting source such as headers or IDL files. SDKs usually contain APIs but often often add compilers, tools, and samples to the mix.

Close a MessageBox after several seconds

I know this question is 8 year old, however there was and is a better solution for this purpose. It's always been there, and still is: User32.dll!MessageBoxTimeout.

This is an undocumented function used by Microsoft Windows, and it does exactly what you want and even more. It supports different languages as well.

C# Import:

[DllImport("user32.dll", SetLastError = true)]
public static extern int MessageBoxTimeout(IntPtr hWnd, String lpText, String lpCaption, uint uType, Int16 wLanguageId, Int32 dwMilliseconds);

[DllImport("user32.dll", SetLastError = true)]
public static extern IntPtr GetForegroundWindow();

How to use it in C#:

uint uiFlags = /*MB_OK*/ 0x00000000 | /*MB_SETFOREGROUND*/  0x00010000 | /*MB_SYSTEMMODAL*/ 0x00001000 | /*MB_ICONEXCLAMATION*/ 0x00000030;

NativeFunctions.MessageBoxTimeout(NativeFunctions.GetForegroundWindow(), $"Kitty", $"Hello", uiFlags, 0, 5000);

Work smarter, not harder.

Where can I find the .apk file on my device, when I download any app and install?

You can do that I believe. It needs root permission. If you want to know where your apk files are stored, open a emulator and then go to

DDMS>File Explorer-> you can see a directory by name "data" -> Click on it and you will see a "app" folder.

Your apks are stored there. In fact just copying a apk directly to the folder works for me with emulators.

Python script to copy text to clipboard

GTK3:

#!/usr/bin/python3

from gi.repository import Gtk, Gdk


class Hello(Gtk.Window):

    def __init__(self):
        super(Hello, self).__init__()
        clipboard = Gtk.Clipboard.get(Gdk.SELECTION_CLIPBOARD)
        clipboard.set_text("hello world", -1)
        Gtk.main_quit()


def main():
    Hello()
    Gtk.main()

if __name__ == "__main__":
    main()

how to call url of any other website in php

use curl php library: http://php.net/manual/en/book.curl.php

direct example: CURL_EXEC:

<?php
// create a new cURL resource
$ch = curl_init();

// set URL and other appropriate options
curl_setopt($ch, CURLOPT_URL, "http://www.example.com/");
curl_setopt($ch, CURLOPT_HEADER, 0);

// grab URL and pass it to the browser
curl_exec($ch);

// close cURL resource, and free up system resources
curl_close($ch);
?>

Change bundle identifier in Xcode when submitting my first app in IOS

Actually you can change it in Build Settings; at the bottom there is a section "User-Defined" where you can easily change PRODUCT_BUNDLE_IDENTIFIER.

I prefer this way, because if you change the info variable you are altering the reference to the other value.

enter image description here

Correct way to detach from a container without stopping it

I consider Ashwin's answer to be the most correct, my old answer is below.


I'd like to add another option here which is to run the container as follows

docker run -dti foo bash

You can then enter the container and run bash with

docker exec -ti ID_of_foo bash

No need to install sshd :)

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

Received the following error

Execution failed for task ':app:transformDexArchiveWithDexMergerForDebug'.

com.android.build.api.transform.TransformException: com.android.dex.DexException: Multiple dex files define Landroid/support/constraint/ConstraintSet$1

Fix : go to Build -> Clean Project

Reverting single file in SVN to a particular revision

So far all answers here seem to have significant downsides, are complicated (need to find the repo URI) or they don't do what the question probably asked for: How to get the Repo in a working state again with that older version of the file.

svn merge -r head:[revision-number-to-revert-to] [file-path] is IMO the cleanest and simplest way to do this. Please note that bringing back a deleted file does not seem to work this way[1]. See also the following question: Better way to revert to a previous SVN revision of a file?

[1] For that you want svn cp -r [rev-number] [repo-URI/file-path]@[rev-number] [repo-URI/file-path] && svn up, see also What is the correct way to restore a deleted file from SVN?

AngularJS 1.2 $injector:modulerr

For those using frameworks that compress, bundle, and minify files, make sure you define each dependency explicitly as these frameworks tend to rename your variables. That happened to me while using ASP.NET BundleConfig.cs to bundle my app scripts together.

Before

app.config(function($routeProvider) {
    $routeProvider.
      when('/', {
          templateUrl: 'list.html',
          controller: 'ListController'
      }).
      when('/items/:itemId', {
          templateUrl: 'details.html',
          controller: 'DetailsController'
      }).
      otherwise({
          redirectTo: '/'
      });
});

After

app.config(["$routeProvider", function($routeProvider) {
    $routeProvider.
      when('/', {
          templateUrl: 'list.html',
          controller: 'ListController'
      }).
      when('/items/:itemId', {
          templateUrl: 'details.html',
          controller: 'DetailsController'
      }).
      otherwise({
          redirectTo: '/'
      });
}]);

Read more here about Angular Dependency Annotation.

Update div with jQuery ajax response html

Almost 5 years later, I think my answer can reduce a little bit the hard work of many people.

Update an element in the DOM with the HTML from the one from the ajax call can be achieved that way

$('#submitform').click(function() {
     $.ajax({
     url: "getinfo.asp",
     data: {
         txtsearch: $('#appendedInputButton').val()
     },
     type: "GET",
     dataType : "html",
     success: function (data){
         $('#showresults').html($('#showresults',data).html());
         // similar to $(data).find('#showresults')
     },
});

or with replaceWith()

// codes

success: function (data){
   $('#showresults').replaceWith($('#showresults',data));
},

momentJS date string add 5 days

UPDATED: January 19, 2016

As of moment 2.8.4 - use .add(5, 'd') (or .add(5, 'days')) instead of .add('d', 5)

var new_date = moment(startdate, "DD-MM-YYYY").add(5, 'days');

Thanks @Bala for the information.

UPDATED: March 21, 2014

This is what you'd have to do to get that format.

Here's an updated fiddle

startdate = "20.03.2014";
var new_date = moment(startdate, "DD-MM-YYYY").add('days', 5);

var day = new_date.format('DD');
var month = new_date.format('MM');
var year = new_date.format('YYYY');

alert(day + '.' + month + '.' + year);

ORIGINAL: March 20, 2014

You're not telling it how/what unit to add. Use -

 var new_date = moment(startdate, "DD-MM-YYYY").add('days', 5);

Python3 integer division

Try this:

a = 1
b = 2
int_div  = a // b

Creating a PHP header/footer

You can use this for header: Important: Put the following on your PHP pages that you want to include the content.

<?php
//at top:
require('header.php'); 
 ?>
 <?php
// at bottom:
require('footer.php');
?>

You can also include a navbar globaly just use this instead:

 <?php
 // At top:
require('header.php'); 
 ?>
  <?php
// At bottom:
require('footer.php');
 ?>
 <?php
 //Wherever navbar goes:
require('navbar.php'); 
?>

In header.php:

 <!DOCTYPE html>
 <html lang="en">
 <head>
    <meta charset="utf-8">
 <meta name="viewport" content="width=device-width, initial-scale=1, shrink-to-fit=no">
 </head>
 <body> 

Do Not close Body or Html tags!
Include html here:

 <?php
 //Or more global php here:

 ?>

Footer.php:

Code here:

<?php
//code

?>

Navbar.php:

<p> Include html code here</p>
<?php
 //Include Navbar PHP code here
 
?>

Benifits:

  • Cleaner main php file (index.php) script.
  • Change the header or footer. etc to change it on all pages with the include— Good for alerts on all pages etc...
  • Time Saving!
  • Faster page loads!
  • you can have as many files to include as needed!
  • server sided!

display:inline vs display:block

display: block; creates a block-level element, whereas display: inline; creates an inline-level element. It's a bit difficult to explain the difference if you're not familiar with the css box model, but suffice to say that block level elements break up the flow of a document, whereas inline elements do not.

Some examples of block level elements include: div, h1, p, and hr HTML tags.

Some examples of inline level elements include: a, span, strong, em, b, and i HTML tags.

Personally, I like to think of inline elements as typographical elements. This isn't entirely or technically correct, but for the most part inline elements do behave a lot like text.

You can read a more through article on the topic here. Seeing as several other people in this thread have quoted it, it may be worth a read.

Undefined reference to pow( ) in C, despite including math.h

You need to link with the math library:

gcc -o sphere sphere.c -lm

The error you are seeing: error: ld returned 1 exit status is from the linker ld (part of gcc that combines the object files) because it is unable to find where the function pow is defined.

Including math.h brings in the declaration of the various functions and not their definition. The def is present in the math library libm.a. You need to link your program with this library so that the calls to functions like pow() are resolved.

Javascript require() function giving ReferenceError: require is not defined

RequireJS is a JavaScript file and module loader. It is optimized for in-browser use, but it can be used in other JavaScript environments, like Rhino and Node. Using a modular script loader like RequireJS will improve the speed and quality of your code.

IE 6+ .......... compatible ?
Firefox 2+ ..... compatible ?
Safari 3.2+ .... compatible ?
Chrome 3+ ...... compatible ?
Opera 10+ ...... compatible ?

http://requirejs.org/docs/download.html

Add this to your project: https://requirejs.org/docs/release/2.3.5/minified/require.js

and take a look at this http://requirejs.org/docs/api.html

get next sequence value from database using hibernate

I found the solution:

public class DefaultPostgresKeyServer
{
    private Session session;
    private Iterator<BigInteger> iter;
    private long batchSize;

    public DefaultPostgresKeyServer (Session sess, long batchFetchSize)
    {
        this.session=sess;
        batchSize = batchFetchSize;
        iter = Collections.<BigInteger>emptyList().iterator();
    }

        @SuppressWarnings("unchecked")
        public Long getNextKey()
        {
            if ( ! iter.hasNext() )
            {
                Query query = session.createSQLQuery( "SELECT nextval( 'mySchema.mySequence' ) FROM generate_series( 1, " + batchSize + " )" );

                iter = (Iterator<BigInteger>) query.list().iterator();
            }
            return iter.next().longValue() ;
        }

}

Using global variables between files?

I just came across this post and thought of posting my solution, just in case of anyone being in the same situation as me, where there are quite some files in the developed program, and you don't have the time to think through the whole import sequence of your modules (if you didn't think of that properly right from the start, such as I did).

In such cases, in the script where you initiate your global(s), simply code a class which says like:

class My_Globals:
  def __init__(self):
    self.global1 = "initial_value_1"
    self.global2 = "initial_value_2"
    ...

and then use, instead of the line in the script where you initiated your globals, instead of

global1 = "initial_value_1"

use

globals = My_Globals()

I was then able to retrieve / change the values of any of these globals via

globals.desired_global

in any script, and these changes were automatically also applied to all the other scripts using them. All worked now, by using the exact same import statements which previously failed, due to the problems mentioned in this post / discussion here. I simply thought of global object's properties being changing dynamically without the need of considering / changing any import logic, in comparison to simple importing of global variables, and that definitely was the quickest and easiest (for later access) approach to solve this kind of problem for me.

Logging in Scala

After using slf4s and logula for a while, I wrote loglady, a simple logging trait wrapping slf4j.

It offers an API similar to that of Python's logging library, which makes the common cases (basic string, simple formatting) trivial and avoids formatting boilerplate.

http://github.com/dln/loglady/

How to convert a byte array to a hex string in Java?

public static String toHexString(byte[] bytes) {

    StringBuilder sb = new StringBuilder();

    if (bytes != null) 
        for (byte b:bytes) {

            final String hexString = Integer.toHexString(b & 0xff);

            if(hexString.length()==1)
                sb.append('0');

            sb.append(hexString);//.append(' ');
        }

      return sb.toString();//.toUpperCase();
}

Simple post to Web Api

It's been quite sometime since I asked this question. Now I understand it more clearly, I'm going to put a more complete answer to help others.

In Web API, it's very simple to remember how parameter binding is happening.

  • if you POST simple types, Web API tries to bind it from the URL
  • if you POST complex type, Web API tries to bind it from the body of the request (this uses a media-type formatter).

  • If you want to bind a complex type from the URL, you'll use [FromUri] in your action parameter. The limitation of this is down to how long your data going to be and if it exceeds the url character limit.

    public IHttpActionResult Put([FromUri] ViewModel data) { ... }

  • If you want to bind a simple type from the request body, you'll use [FromBody] in your action parameter.

    public IHttpActionResult Put([FromBody] string name) { ... }

as a side note, say you are making a PUT request (just a string) to update something. If you decide not to append it to the URL and pass as a complex type with just one property in the model, then the data parameter in jQuery ajax will look something like below. The object you pass to data parameter has only one property with empty property name.

var myName = 'ABC';
$.ajax({url:.., data: {'': myName}});

and your web api action will look something like below.

public IHttpActionResult Put([FromBody] string name){ ... }

This asp.net page explains it all. http://www.asp.net/web-api/overview/formats-and-model-binding/parameter-binding-in-aspnet-web-api

How do I detach objects in Entity Framework Code First?

If you want to detach existing object follow @Slauma's advice. If you want to load objects without tracking changes use:

var data = context.MyEntities.AsNoTracking().Where(...).ToList();

As mentioned in comment this will not completely detach entities. They are still attached and lazy loading works but entities are not tracked. This should be used for example if you want to load entity only to read data and you don't plan to modify them.

How to find index of list item in Swift?

tl;dr:

For classes, you might be looking for:

let index = someArray.firstIndex{$0 === someObject}

Full answer:

I think it's worth mentioning that with reference types (class) you might want to perform an identity comparison, in which case you just need to use the === identity operator in the predicate closure:


Swift 5, Swift 4.2:

let person1 = Person(name: "John")
let person2 = Person(name: "Sue")
let person3 = Person(name: "Maria")
let person4 = Person(name: "Loner")

let people = [person1, person2, person3]

let indexOfPerson1 = people.firstIndex{$0 === person1} // 0
let indexOfPerson2 = people.firstIndex{$0 === person2} // 1
let indexOfPerson3 = people.firstIndex{$0 === person3} // 2
let indexOfPerson4 = people.firstIndex{$0 === person4} // nil

Note that the above syntax uses trailing closures syntax, and is equivalent to:

let indexOfPerson1 = people.firstIndex(where: {$0 === person1})


Swift 4 / Swift 3 - the function used to be called index

Swift 2 - the function used to be called indexOf

* Note the relevant and useful comment by paulbailey about class types that implement Equatable, where you need to consider whether you should be comparing using === (identity operator) or == (equality operator). If you decide to match using ==, then you can simply use the method suggested by others (people.firstIndex(of: person1)).

How do I get IntelliJ to recognize common Python modules?

Few steps that helped me (some of them are mentioned above):

Open project structure by:

command + ; (mac users) OR right click on the project -> Open Module Settings

  1. Facets -> + -> Python -> <your-project> -> OK
  2. Modules -> Python -> <select python interpreter>
  3. Project -> Project SDK -> <select relevant SDK>
  4. SDKs -> <make sure it's the right one>

Click OK.

Open Run/Debug Configurations by: Run -> Edit Configurations

  1. Python Interpreter -> <make sure it's the right one>

Click OK.

How do you allow spaces to be entered using scanf?

You can use the fgets() function to read a string or use scanf("%[^\n]s",name); so string reading will terminate upon encountering a newline character.

ImportError: No module named Image

The PIL distribution is mispackaged for egg installation.

Install Pillow instead, the friendly PIL fork.

invalid byte sequence for encoding "UTF8"

copy tablename from 'filepath\filename' DELIMITERS '=' ENCODING 'WIN1252';

you can try this to handle UTF8 encoding.

How to color the Git console?

In your ~/.gitconfig file, simply add this:

[color]
  ui = auto

It takes care of all your git commands.

Failed to resolve version for org.apache.maven.archetypes

The right way to solve my problem are as followed. Hope to be helpful to others. the errors informations.

Could not resolve archetype org.apache.maven.archetypes:maven-archetype-webapp:1.0 from any of the configured repositories. Could not resolve artifact org.apache.maven.archetypes:maven-archetype-webapp:pom:1.0 Failure to transfer org.apache.maven.archetypes:maven-archetype-webapp:pom:1.0

  1. Delete the maven-archetype-webapp:1.0 in the directory ~/.m2/repository/org/Apache/maven/archetypes

  2. Download the maven-archetype-webapp:1.0 and the maven-archetype-webapp-1.0.pom from http://maven.ibiblio.org/maven2/org/apache/maven/archetypes/maven-archetype-webapp/1.0/

  3. execute mvn install:install-file -DgroupId=org.apache.maven.archetypes -DartifactId=maven-archetype-quickstart -Dversion=1.1 -Dpackaging=jar -Dfile=???maven-archetype-webapp-1.0???.

  4. try to establish a maven project of webapp to test whether the problem has solved.

Name does not exist in the current context

I also faced a similar issue, the problem was the form was inside a folder and the file .aspx.designer.cs I had the namespace referencing specifically to that directory; which caused the error to appear in several components:

El nombre no existe en el contexto actual

This in your case, a possible solution is to leave the namespace line of the Members_Jobs.aspx.designer.cs file specified globally, ie change this

namespace stman.Members {

For this

namespace stman {

It's what helped me solve the problem.

I hope to be helpful

TypeError: sequence item 0: expected string, int found

The answers by cval and Priyank Patel work great. However, be aware that some values could be unicode strings and therefore may cause the str to throw a UnicodeEncodeError error. In that case, replace the function str by the function unicode.

For example, assume the string Libië (Dutch for Libya), represented in Python as the unicode string u'Libi\xeb':

print str(u'Libi\xeb')

throws the following error:

Traceback (most recent call last):
  File "/Users/tomasz/Python/MA-CIW-Scriptie/RecreateTweets.py", line 21, in <module>
    print str(u'Libi\xeb')
UnicodeEncodeError: 'ascii' codec can't encode character u'\xeb' in position 4: ordinal not in range(128)

The following line, however, will not throw an error:

print unicode(u'Libi\xeb') # prints Libië

So, replace:

values = ','.join([str(i) for i in value_list])

by

values = ','.join([unicode(i) for i in value_list])

to be safe.

What is Node.js?

There is a very good fast food place analogy that best explains the event driven model of Node.js, see the full article, Node.js, Doctor’s Offices and Fast Food Restaurants – Understanding Event-driven Programming

Here is a summary:

If the fast food joint followed a traditional thread-based model, you'd order your food and wait in line until you received it. The person behind you wouldn't be able to order until your order was done. In an event-driven model, you order your food and then get out of line to wait. Everyone else is then free to order.

Node.js is event-driven, but most web servers are thread-based.York explains how Node.js works:

  • You use your web browser to make a request for "/about.html" on a Node.js web server.

  • The Node.js server accepts your request and calls a function to retrieve that file from disk.

  • While the Node.js server is waiting for the file to be retrieved, it services the next web request.

  • When the file is retrieved, there is a callback function that is inserted in the Node.js servers queue.

  • The Node.js server executes that function which in this case would render the "/about.html" page and send it back to your web browser."

ValueError: cannot reshape array of size 30470400 into shape (50,1104,104)

It seems that there is a typo, since 1104*1104*50=60940800 and you are trying to reshape to dimensions 50,1104,104. So it seems that you need to change 104 to 1104.

How to enable authentication on MongoDB through Docker?

@jbochniak: Thanks, although at first read I thought I've already discovered all of this, it turned out that your example (esp. the version of the Mongo Docker image) helped me out!

That version (v3.4.2) and the v3.4 (currently corresponding to v3.4.3) still support 'MONGO_INITDB_ROOT' specified through those variables, as of v3.5 (at least tags '3' and 'latest') DON'T work as described in your answer and in the docs.

I quickly had a look at the code on GitHub, but saw similar usage of these variables and couldn't find the bug immediately, should do so before filing this as a bug...

How to undo a SQL Server UPDATE query?

If you can catch this in time and you don't have the ability to ROLLBACK or use the transaction log, you can take a backup immediately and use a tool like Redgate's SQL Data Compare to generate a script to "restore" the affected data. This worked like a charm for me. :)

JSHint and jQuery: '$' is not defined

You can also add two lines to your .jshintrc

  "globals": {
    "$": false,
    "jQuery": false
  }

This tells jshint that there are two global variables.

R: Break for loop

your break statement should break out of the for (in in 1:n).

Personally I am always wary with break statements and double check it by printing to the console to double check that I am in fact breaking out of the right loop. So before you test add the following statement, which will let you know if you break before it reaches the end. However, I have no idea how you are handling the variable n so I don't know if it would be helpful to you. Make a n some test value where you know before hand if it is supposed to break out or not before reaching n.

for (in in 1:n)
{
    if (in == n)         #add this statement
    {
        "sorry but the loop did not break"
    }

    id_novo <- new_table_df$ID[in]
    if(id_velho==id_novo)
    {
        break
    }
    else if(in == n)
    {
        sold_df <- rbind(sold_df,old_table_df[out,])
    }
}

Protractor : How to wait for page complete after click a button?

In this case, you can used:

Page Object:

    waitForURLContain(urlExpected: string, timeout: number) {
        try {
            const condition = browser.ExpectedConditions;
            browser.wait(condition.urlContains(urlExpected), timeout);
        } catch (e) {
            console.error('URL not contain text.', e);
        };
    }

Page Test:

page.waitForURLContain('abc#/efg', 30000);

how to check if input field is empty

As javascript is dynamically typed, rather than using the .length property as above you can simply treat the input value as a boolean:

var input = $.trim($("#spa").val());

if (input) {
    // Do Stuff
}

You can also extract the logic out into functions, then by assigning a class and using the each() method the code is more dynamic if, for example, in the future you wanted to add another input you wouldn't need to change any code.

So rather than hard coding the function call into the input markup, you can give the inputs a class, in this example it's test, and use:

$(".test").each(function () {
    $(this).keyup(function () {
        $("#submit").prop("disabled", CheckInputs());
    });
});

which would then call the following and return a boolean value to assign to the disabled property:

function CheckInputs() {
    var valid = false;
    $(".test").each(function () {
        if (valid) { return valid; }
        valid = !$.trim($(this).val());
    });
    return valid;
}

You can see a working example of everything I've mentioned in this JSFiddle.

Unable to show a Git tree in terminal

git log --oneline --decorate --all --graph

A visual tree with branch names included.

Use this to add it as an alias

git config --global alias.tree "log --oneline --decorate --all --graph"

You call it with

git tree

Git Tree

LaTex left arrow over letter in math mode

Use \overleftarrow to create a long arrow to the left.

\overleftarrow{blahblahblah}

LaTeX output

How to count the occurrence of certain item in an ndarray?

This funktion returns the number of occurences of a variable in an array:

def count(array,variable):
    number = 0
    for i in range(array.shape[0]):
        for j in range(array.shape[1]):
            if array[i,j] == variable:
                number += 1
    return number

How to find all occurrences of a substring?

Again, old thread, but here's my solution using a generator and plain str.find.

def findall(p, s):
    '''Yields all the positions of
    the pattern p in the string s.'''
    i = s.find(p)
    while i != -1:
        yield i
        i = s.find(p, i+1)

Example

x = 'banananassantana'
[(i, x[i:i+2]) for i in findall('na', x)]

returns

[(2, 'na'), (4, 'na'), (6, 'na'), (14, 'na')]

How to increase application heap size in Eclipse?

In the run configuration you want to customize (just click on it) open the tab Arguments and add -Xmx2048min the VM arguments section. You might want to set the -Xms as well (small heap size).

Copy text from nano editor to shell

M-^ is copy Text. "M" in my environment is "Esc" key ! not "Ctrl"; so I use Esc + 6 to copy that.

[nano help] Escape-key sequences are notated with the Meta (M-) symbol and can be entered using either the Esc, Alt, or Meta key depending on your keyboard setup.

Why am I getting "void value not ignored as it ought to be"?

srand doesn't return anything so you can't initialize a with its return value because, well, because it doesn't return a value. Did you mean to call rand as well?

Check if a string is a palindrome

This C# method will check for even and odd length palindrome string (Recursive Approach):

public static bool IsPalindromeResursive(int rightIndex, int leftIndex, char[] inputString)
{
    if (rightIndex == leftIndex || rightIndex < leftIndex)
        return true;
    if (inputString[rightIndex] == inputString[leftIndex])
        return IsPalindromeResursive(--rightIndex, ++leftIndex, inputString);
    else
        return false;            
}

Displaying output of a remote command with Ansible

Prints pubkey and avoid the changed status by adding changed_when: False to cat task:

- name: Generate SSH keys for vagrant user   
  user: name=vagrant generate_ssh_key=yes ssh_key_bits=2048

- name: Check SSH public key   
  command: /bin/cat $home_directory/.ssh/id_rsa.pub
  register: cat
  changed_when: False

- name: Print SSH public key
  debug: var=cat.stdout

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

ASP.NET Web Application Message Box

Right click the solution explorer and choose the add reference.one dialog box will be appear. On that select (.net)-> System.windows.form. Imports System.Windows.Forms (vb) and using System.windows.forms(C#) copy this in your coding and then write messagebox.show("").

How can I get the class name from a C++ object?

You can try this:

template<typename T>
inline const char* getTypeName() {
  return typeid(T).name();
}

#define DEFINE_TYPE_NAME(type, type_name)  \
  template<>                               \
  inline const char* getTypeName<type>() { \
    return type_name;                      \
  }

DEFINE_TYPE_NAME(int, "int")
DEFINE_TYPE_NAME(float, "float")
DEFINE_TYPE_NAME(double, "double")
DEFINE_TYPE_NAME(std::string, "string")
DEFINE_TYPE_NAME(bool, "bool")
DEFINE_TYPE_NAME(uint32_t, "uint")
DEFINE_TYPE_NAME(uint64_t, "uint")
// add your custom types' definitions

And call it like that:

void main() {
 std::cout << getTypeName<int>();
}

How to add anchor tags dynamically to a div in Javascript?

here's a pure Javascript alternative:

var mydiv = document.getElementById("myDiv");
var aTag = document.createElement('a');
aTag.setAttribute('href',"yourlink.htm");
aTag.innerText = "link text";
mydiv.appendChild(aTag);

XAMPP PORT 80 is Busy / EasyPHP error in Apache configuration file:

xampp port 80 is busy when some other application is using the same port at that time. This can be solved by using one of the following methods:

  1. Detect the application which is using the port 80 and close it.
  2. This one is more efficient. xampp installs apache server with default port 80. So, you can change this port manually to any number.

Just find the httpd.conf file in xampp installation and replace the following line of code.

#Listen 12.34.56.78:1234
Listen 80

to any port number of your choice. Here, i have taken 8000.

#Listen 12.34.56.78:1234
Listen 8000

Find the following code in the same file httpd.conf

ServerName localhost

Replace with the following, take the same number you have used in upper code.

ServerName localhost:8000

For detailed answer, check http://webolute.com/blog/programming/this-may-be-due-to-a-blocked-port-missing-dependencies

How to convert an entire MySQL database characterset and collation to UTF-8?

DELIMITER $$  

CREATE PROCEDURE `databasename`.`update_char_set`()  

BEGIN  
 DECLARE done INT DEFAULT 0;  
 DECLARE t_sql VARCHAR(256);  
 DECLARE tableName VARCHAR(128);  
 DECLARE lists CURSOR FOR SELECT table_name FROM `information_schema`.`TABLES` WHERE table_schema = 'databasename';  
 DECLARE CONTINUE HANDLER FOR SQLSTATE '02000' SET done = 1;  
 OPEN lists;  
 FETCH lists INTO tableName;  
 REPEAT  
    SET @t_sql = CONCAT('ALTER TABLE ', tableName, ' CONVERT TO CHARACTER SET utf8 COLLATE utf8_general_ci');  
    PREPARE stmt FROM @t_sql;  
    EXECUTE stmt;  
    DEALLOCATE PREPARE stmt;  
 FETCH lists INTO tableName;  
 UNTIL done END REPEAT;  
 CLOSE lists;  
END$$  

DELIMITER ;  

CALL databasename.update_char_set();

Turn off iPhone/Safari input element rounding

I used a simple border-radius: 0; to remove the rounded corners for the text input types.

T-sql - determine if value is integer

Use TRY_CONVERT which is an SQL alternative to TryParse in .NET. IsNumeric() isn’t aware that empty strings are counted as (integer)zero, and that some perfectly valid money symbols, by themselves, are not converted to (money)zero. reference

SELECT @MY_VAR = CASE WHEN TRY_CONVERT(INT,MY_FIELD) IS NOT NULL THEN MY_FIELD
                 ELSE 0
                 END
FROM MY_TABLE
WHERE MY_OTHER_FIELD = 'MY_FILTER'

VT-x is disabled in the BIOS for both all CPU modes (VERR_VMX_MSR_ALL_VMX_DISABLED)

Follow the steps below in Oracle VM VirtualBox Manager:

  1. Select the Virtual device and choose Settings
  2. Navigate to System and click the Processor tab
  3. Tick the check-box, Enable PAE/NX
  4. Click OK and you are done

To verify, start the Virtual device from Oracle VM VirtualBox. If all has gone well, the device boots up.

Close this device and open it from Genymotion.

What are the ascii values of up down left right?

The Ascii codes for arrow characters are the following: ? 24 ? 25 ? 26 ? 27

List to array conversion to use ravel() function

If all you want is calling ravel on your (nested, I s'pose?) list, you can do that directly, numpy will do the casting for you:

L = [[1,None,3],["The", "quick", object]]
np.ravel(L)
# array([1, None, 3, 'The', 'quick', <class 'object'>], dtype=object)

Also worth mentioning that you needn't go through numpy at all.

Node.js Mongoose.js string to ObjectId function

You can use this also

const { ObjectId } = require('mongodb');
const _id = ObjectId("4eb6e7e7e9b7f4194e000001");

it's simplest way to do it

How to rearrange Pandas column sequence?

Feel free to disregard this solution as subtracting a list from an Index does not preserve the order of the original Index, if that's important.

In [61]: df.reindex(columns=pd.Index(['x', 'y']).append(df.columns - ['x', 'y']))
Out[61]: 
    x  y  a  b
0   3 -1  1  2
1   6 -2  2  4
2   9 -3  3  6
3  12 -4  4  8

Can we make unsigned byte in Java

There are no primitive unsigned bytes in Java. The usual thing is to cast it to bigger type:

int anUnsignedByte = (int) aSignedByte & 0xff;

How to install Ruby 2.1.4 on Ubuntu 14.04

Use RVM (Ruby Version Manager) to install and manage any versions of Ruby. You can have multiple versions of Ruby installed on the machine and you can easily select the one you want.

To install RVM type into terminal:

\curl -sSL https://get.rvm.io | bash -s stable

And let it work. After that you will have RVM along with Ruby installed.

Source: RVM Site

What is the difference between connection and read timeout for sockets?

  1. What is the difference between connection and read timeout for sockets?

The connection timeout is the timeout in making the initial connection; i.e. completing the TCP connection handshake. The read timeout is the timeout on waiting to read data1. If the server (or network) fails to deliver any data <timeout> seconds after the client makes a socket read call, a read timeout error will be raised.

  1. What does connection timeout set to "infinity" mean? In what situation can it remain in an infinitive loop? and what can trigger that the infinity-loop dies?

It means that the connection attempt can potentially block for ever. There is no infinite loop, but the attempt to connect can be unblocked by another thread closing the socket. (A Thread.interrupt() call may also do the trick ... not sure.)

  1. What does read timeout set to "infinity" mean? In what situation can it remain in an infinite loop? What can trigger that the infinite loop to end?

It means that a call to read on the socket stream may block for ever. Once again there is no infinite loop, but the read can be unblocked by a Thread.interrupt() call, closing the socket, and (of course) the other end sending data or closing the connection.


1 - It is not ... as one commenter thought ... the timeout on how long a socket can be open, or idle.

UITableView, Separator color where to set?

Now you should be able to do it directly in the IB.

Not sure though, if this was available when the question was posted originally.

enter image description here

Reading a JSP variable from JavaScript

Assuming you are talking about JavaScript in an HTML document.

You can't do this directly since, as far as the JSP is concerned, it is outputting text, and as far as the page is concerned, it is just getting an HTML document.

You have to generate JavaScript code to instantiate the variable, taking care to escape any characters with special meaning in JS. If you just dump the data (as proposed by some other answers) you will find it falling over when the data contains new lines, quote characters and so on.

The simplest way to do this is to use a JSON library (there are a bunch listed at the bottom of http://json.org/ ) and then have the JSP output:

<script type="text/javascript">
    var myObject = <%= the string output by the JSON library %>;
</script>

This will give you an object that you can access like:

myObject.someProperty

in the JS.

Should Gemfile.lock be included in .gitignore?

The Bundler docs address this question as well:

ORIGINAL: http://gembundler.com/v1.3/rationale.html

EDIT: http://web.archive.org/web/20160309170442/http://bundler.io/v1.3/rationale.html

See the section called "Checking Your Code into Version Control":

After developing your application for a while, check in the application together with the Gemfile and Gemfile.lock snapshot. Now, your repository has a record of the exact versions of all of the gems that you used the last time you know for sure that the application worked. Keep in mind that while your Gemfile lists only three gems (with varying degrees of version strictness), your application depends on dozens of gems, once you take into consideration all of the implicit requirements of the gems you depend on.

This is important: the Gemfile.lock makes your application a single package of both your own code and the third-party code it ran the last time you know for sure that everything worked. Specifying exact versions of the third-party code you depend on in your Gemfile would not provide the same guarantee, because gems usually declare a range of versions for their dependencies.

The next time you run bundle install on the same machine, bundler will see that it already has all of the dependencies you need, and skip the installation process.

Do not check in the .bundle directory, or any of the files inside it. Those files are specific to each particular machine, and are used to persist installation options between runs of the bundle install command.

If you have run bundle pack, the gems (although not the git gems) required by your bundle will be downloaded into vendor/cache. Bundler can run without connecting to the internet (or the RubyGems server) if all the gems you need are present in that folder and checked in to your source control. This is an optional step, and not recommended, due to the increase in size of your source control repository.

Adding a slide effect to bootstrap dropdown

Expanded answer, was my first answer so excuse if there wasn’t enough detail before.

For Bootstrap 3.x I personally prefer CSS animations and I've been using animate.css & along with the Bootstrap Dropdown Javascript Hooks. Although it might not have the exactly effect you're after it's a pretty flexible approach.

Step 1: Add animate.css to your page with the head tags:

<link rel="stylesheet" href="https://cdnjs.cloudflare.com/ajax/libs/animate.css/3.4.0/animate.min.css">

Step 2: Use the standard Bootstrap HTML on the trigger:

<div class="dropdown">
  <button type="button" data-toggle="dropdown">Dropdown trigger</button>

  <ul class="dropdown-menu">
    ...
  </ul>
</div>

Step 3: Then add 2 custom data attributes to the dropdrop-menu element; data-dropdown-in for the in animation and data-dropdown-out for the out animation. These can be any animate.css effects like fadeIn or fadeOut

<ul class="dropdown-menu" data-dropdown-in="fadeIn" data-dropdown-out="fadeOut">
......
</ul>

Step 4: Next add the following Javascript to read the data-dropdown-in/out data attributes and react to the Bootstrap Javascript API hooks/events (http://getbootstrap.com/javascript/#dropdowns-events):

var dropdownSelectors = $('.dropdown, .dropup');

// Custom function to read dropdown data
// =========================
function dropdownEffectData(target) {
  // @todo - page level global?
  var effectInDefault = null,
      effectOutDefault = null;
  var dropdown = $(target),
      dropdownMenu = $('.dropdown-menu', target);
  var parentUl = dropdown.parents('ul.nav'); 

  // If parent is ul.nav allow global effect settings
  if (parentUl.size() > 0) {
    effectInDefault = parentUl.data('dropdown-in') || null;
    effectOutDefault = parentUl.data('dropdown-out') || null;
  }

  return {
    target:       target,
    dropdown:     dropdown,
    dropdownMenu: dropdownMenu,
    effectIn:     dropdownMenu.data('dropdown-in') || effectInDefault,
    effectOut:    dropdownMenu.data('dropdown-out') || effectOutDefault,  
  };
}

// Custom function to start effect (in or out)
// =========================
function dropdownEffectStart(data, effectToStart) {
  if (effectToStart) {
    data.dropdown.addClass('dropdown-animating');
    data.dropdownMenu.addClass('animated');
    data.dropdownMenu.addClass(effectToStart);    
  }
}

// Custom function to read when animation is over
// =========================
function dropdownEffectEnd(data, callbackFunc) {
  var animationEnd = 'webkitAnimationEnd mozAnimationEnd MSAnimationEnd oanimationend animationend';
  data.dropdown.one(animationEnd, function() {
    data.dropdown.removeClass('dropdown-animating');
    data.dropdownMenu.removeClass('animated');
    data.dropdownMenu.removeClass(data.effectIn);
    data.dropdownMenu.removeClass(data.effectOut);

    // Custom callback option, used to remove open class in out effect
    if(typeof callbackFunc == 'function'){
      callbackFunc();
    }
  });
}

// Bootstrap API hooks
// =========================
dropdownSelectors.on({
  "show.bs.dropdown": function () {
    // On show, start in effect
    var dropdown = dropdownEffectData(this);
    dropdownEffectStart(dropdown, dropdown.effectIn);
  },
  "shown.bs.dropdown": function () {
    // On shown, remove in effect once complete
    var dropdown = dropdownEffectData(this);
    if (dropdown.effectIn && dropdown.effectOut) {
      dropdownEffectEnd(dropdown, function() {}); 
    }
  },  
  "hide.bs.dropdown":  function(e) {
    // On hide, start out effect
    var dropdown = dropdownEffectData(this);
    if (dropdown.effectOut) {
      e.preventDefault();   
      dropdownEffectStart(dropdown, dropdown.effectOut);   
      dropdownEffectEnd(dropdown, function() {
        dropdown.dropdown.removeClass('open');
      }); 
    }    
  }, 
});

Step 5 (optional): If you want to speed up or alter the animation you can do so with CSS like the following:

.dropdown-menu.animated {
  /* Speed up animations */
  -webkit-animation-duration: 0.55s;
  animation-duration: 0.55s;
  -webkit-animation-timing-function: ease;
  animation-timing-function: ease;
}

Wrote an article with more detail and a download if anyones interested: article: http://bootbites.com/tutorials/bootstrap-dropdown-effects-animatecss

Hope that’s helpful & this second write up has the level of detail that’s needed Tom

Replace NA with 0 in a data frame column

First, here's some sample data:

set.seed(1)
dat <- data.frame(one = rnorm(15),
                 two = sample(LETTERS, 15),
                 three = rnorm(15),
                 four = runif(15))
dat <- data.frame(lapply(dat, function(x) { x[sample(15, 5)] <- NA; x }))
head(dat)
#          one  two       three      four
# 1         NA    M  0.80418951 0.8921983
# 2  0.1836433    O -0.05710677        NA
# 3 -0.8356286    L  0.50360797 0.3899895
# 4         NA    E          NA        NA
# 5  0.3295078    S          NA 0.9606180
# 6 -0.8204684 <NA> -1.28459935 0.4346595

Here's our replacement:

dat[["four"]][is.na(dat[["four"]])] <- 0
head(dat)
#          one  two       three      four
# 1         NA    M  0.80418951 0.8921983
# 2  0.1836433    O -0.05710677 0.0000000
# 3 -0.8356286    L  0.50360797 0.3899895
# 4         NA    E          NA 0.0000000
# 5  0.3295078    S          NA 0.9606180
# 6 -0.8204684 <NA> -1.28459935 0.4346595

Alternatively, you can, of course, write dat$four[is.na(dat$four)] <- 0

How to fade changing background image

This may help

HTML

<div id="textcontainer">        
    <span id="sometext">This is some information </span>
    <div id="container">

    </div>
</div>

CSS

#textcontainer{
    position:relative;
    border:1px solid #000;
    width :300px;
    height:300px;
}
#container{
    background-image :url("http://dcooper.org/gallery/cf_appicon.jpg");
    width :100%;
    height:100%;
}
#sometext{
    position:absolute;
    top:50%;
    left:50%;
}

Js

$('#container').css('opacity','.1');

Exception of type 'System.OutOfMemoryException' was thrown.

Another thing to try is

Tools -> Options -> search for IIS -> tick Use the 64 bit version of IIS Express for web sites and projects.

Use the 64 bit version of IIS Express for web sites and projects screenshot

Disable scrolling in webview?

I don't know if you still need it or not, but here is the solution:

appView = (WebView) findViewById(R.id.appView); 
appView.setVerticalScrollBarEnabled(false);
appView.setHorizontalScrollBarEnabled(false);

How do the post increment (i++) and pre increment (++i) operators work in Java?

I believe however if you combine all of your statements and run it in Java 8.1 you will get a different answer, at least that's what my experience says.

The code will work like this:

int a=5,i;

i=++a + ++a + a++;            /*a = 5;
                                i=++a + ++a + a++; =>
                                i=6 + 7 + 7; (a=8); i=20;*/

i=a++ + ++a + ++a;           /*a = 5;
                                i=a++ + ++a + ++a; =>
                                i=8 + 10 + 11; (a=11); i=29;*/

a=++a + ++a + a++;            /*a=5;
                                a=++a + ++a + a++; =>
                                a=12 + 13 + 13;  a=38;*/

System.out.println(a);        //output: 38
System.out.println(i);         //output: 29

Table Naming Dilemma: Singular vs. Plural Names

I will just give my opinion why I use singular names.

For example, I need to get all the fields from an user:

-- Select every fields from 'user' table
SELECT * FROM user

I need the name of the user that is 21 years old:

-- Select every fields from 'user' table which have 21 years old
SELECT * FROM user WHERE age = '21'

Of course the plural way can be used by the same means, but for my brain to read, I really think that's the right way to go.

How to set background image of a view?

simple way :

   -(void) viewDidLoad {
   self.view.backgroundColor = [[UIColor alloc] initWithPatternImage:[UIImage       imageNamed:@"background.png"]];
    [super viewDidLoad];
    }

Dump all tables in CSV format using 'mysqldump'

This worked well for me:

mysqldump <DBNAME> --fields-terminated-by ',' \
--fields-enclosed-by '"' --fields-escaped-by '\' \
--no-create-info --tab /var/lib/mysql-files/

Or if you want to only dump a specific table:

mysqldump <DBNAME> <TABLENAME> --fields-terminated-by ',' \
--fields-enclosed-by '"' --fields-escaped-by '\' \
--no-create-info --tab /var/lib/mysql-files/

I'm dumping to /var/lib/mysql-files/ to avoid this error:

mysqldump: Got error: 1290: The MySQL server is running with the --secure-file-priv option so it cannot execute this statement when executing 'SELECT INTO OUTFILE'

How to plot data from multiple two column text files with legends in Matplotlib?

I feel the simplest way would be

 from matplotlib import pyplot;
 from pylab import genfromtxt;  
 mat0 = genfromtxt("data0.txt");
 mat1 = genfromtxt("data1.txt");
 pyplot.plot(mat0[:,0], mat0[:,1], label = "data0");
 pyplot.plot(mat1[:,0], mat1[:,1], label = "data1");
 pyplot.legend();
 pyplot.show();
  1. label is the string that is displayed on the legend
  2. you can plot as many series of data points as possible before show() to plot all of them on the same graph This is the simple way to plot simple graphs. For other options in genfromtxt go to this url.

Trigger a button click with JavaScript on the Enter key in a text box

Use keypress and event.key === "Enter" with modern JS!

const textbox = document.getElementById("txtSearch");
textbox.addEventListener("keypress", function onEvent(event) {
    if (event.key === "Enter") {
        document.getElementById("btnSearch").click();
    }
});

Mozilla Docs

Supported Browsers

Validation to check if password and confirm password are same is not working

I presume you've got validate_required() function from this page: http://www.w3schools.com/js/js_form_validation.asp?

function validate_required(field,alerttxt)
{
with (field)
  {
  if (value==null||value=="")
    {
    alert(alerttxt);return false;
    }
  else
    {
    return true;
    }
  }
}

In this case your last condition will not work as you expect it.

You can replace it with this:

if (password.value != cpassword.value) { 
   alert("Your password and confirmation password do not match.");
   cpassword.focus();
   return false; 
}

Pandas aggregate count distinct

How about either of:

>>> df
         date  duration user_id
0  2013-04-01        30    0001
1  2013-04-01        15    0001
2  2013-04-01        20    0002
3  2013-04-02        15    0002
4  2013-04-02        30    0002
>>> df.groupby("date").agg({"duration": np.sum, "user_id": pd.Series.nunique})
            duration  user_id
date                         
2013-04-01        65        2
2013-04-02        45        1
>>> df.groupby("date").agg({"duration": np.sum, "user_id": lambda x: x.nunique()})
            duration  user_id
date                         
2013-04-01        65        2
2013-04-02        45        1

How to add Tomcat Server in eclipse

If by mistake, you have deleted your Tomcat Server and Eclipse is not showing more options (Next button will be inactive) then in this case follow the bellow steps:

  1. First remove the two files from the following path:

    • Path : workspace/.metadata/.plugins/org.eclipse.runtime/.settings/
    • And that two files are :

      1. org.eclipse.wst.server.core.prefs
      2. org.eclipse.jst/server.tomcat.core.prefs
    • After deleting/removing the above two files from the workspace, Restart the Eclipse IDE.

    • Change to the Server View, Right Click 'New', Window 'Define a New Server' is shown, --> Select the Apache Folder, choose Tomcat-Version

    • Browse to the unzipped 'Apache-Tomcat folder', choose the second level

    • Now you are able to add/configure your new Tomcat Server. (Now you will see the 'Next' button will become active, and you can then follow the normal instructions)

Check if a variable exists in a list in Bash

Examples

$ in_list super test me out
NO

$ in_list "super dude" test me out
NO

$ in_list "super dude" test me "super dude"
YES

# How to use in another script
if [ $(in_list $1 OPTION1 OPTION2) == "NO" ]
then
  echo "UNKNOWN type for param 1: Should be OPTION1 or OPTION2"
  exit;
fi

in_list

function show_help()
{
  IT=$(CAT <<EOF

  usage: SEARCH_FOR {ITEM1} {ITEM2} {ITEM3} ...

  e.g. 

  a b c d                    -> NO
  a b a d                    -> YES
  "test me" how "test me"    -> YES

  )
  echo "$IT"
  exit
}

if [ "$1" == "help" ]
then
  show_help
fi

if [ "$#" -eq 0 ]; then
  show_help
fi

SEARCH_FOR=$1
shift;

for ITEM in "$@"
do
  if [ "$SEARCH_FOR" == "$ITEM" ]
  then
    echo "YES"
    exit;
  fi
done

echo "NO"

Auto-redirect to another HTML page

One of these will work...

_x000D_
_x000D_
<head>_x000D_
  <meta http-equiv='refresh' content='0; URL=http://example.com/'>_x000D_
</head>
_x000D_
_x000D_
_x000D_

...or it can done with JavaScript:

_x000D_
_x000D_
window.location.href = 'https://example.com/';
_x000D_
_x000D_
_x000D_

How to redirect single url in nginx?

Put this in your server directive:

location /issue {
   rewrite ^/issue(.*) http://$server_name/shop/issues/custom_issue_name$1 permanent;
 }

Or duplicate it:

location /issue1 {
   rewrite ^/.* http://$server_name/shop/issues/custom_issue_name1 permanent;
}
location /issue2 {
   rewrite ^.* http://$server_name/shop/issues/custom_issue_name2 permanent;
}
 ...

AJAX cross domain call

Here is an easy way of how you can do it, without having to use anything fancy, or even JSON.

First, create a server side script to handle your requests. Something like http://www.example.com/path/handler.php

You will call it with parameters, like this: .../handler.php?param1=12345&param2=67890

Inside it, after processing the recieved data, output:

document.serverResponse('..all the data, in any format that suits you..');
// Any code could be used instead, because you dont have to encode this data
// All your output will simply be executed as normal javascript

Now, in the client side script, use the following:

document.serverResponse = function(param){ console.log(param) }

var script = document.createElement('script');
script.src='http://www.example.com/path/handler.php?param1=12345&param2=67890';
document.head.appendChild(script);

The only limit of this approach, is the max length of parameters that you can send to the server. But, you can always send multiple requests.

Mongoose limit/offset and count query

There is a library that will do all of this for you, check out mongoose-paginate-v2

Is it possible to embed animated GIFs in PDFs?

I do it for beamer presentations,

provide tmp-0.png through tmp-34.png

\usepackage{animate}

\begin{frame}{Torque Generating Mechanism}
  \animategraphics[loop,controls,width=\linewidth]{12}{output/tmp-}{0}{34}
\end{frame}

Php, wait 5 seconds before executing an action

In https://www.php.net/manual/es/function.usleep.php

<?php
// Wait 2 seconds
usleep(2000000);

// if you need 5 seconds
usleep(5000000);
?>

Meaning of "referencing" and "dereferencing" in C

Referencing

& is the reference operator. It will refer the memory address to the pointer variable.

Example:

int *p;
int a=5;
p=&a; // Here Pointer variable p refers to the address of integer variable a.

Dereferencing

Dereference operator * is used by the pointer variable to directly access the value of the variable instead of its memory address.

Example:

int *p;
int a=5;
p=&a;
int value=*p; // Value variable will get the value of variable a that pointer variable p pointing to.

Making heatmap from pandas DataFrame

Please note that the authors of seaborn only want seaborn.heatmap to work with categorical dataframes. It's not general.

If your index and columns are numeric and/or datetime values, this code will serve you well.

Matplotlib heat-mapping function pcolormesh requires bins instead of indices, so there is some fancy code to build bins from your dataframe indices (even if your index isn't evenly spaced!).

The rest is simply np.meshgrid and plt.pcolormesh.

import pandas as pd
import numpy as np
import matplotlib.pyplot as plt

def conv_index_to_bins(index):
    """Calculate bins to contain the index values.
    The start and end bin boundaries are linearly extrapolated from 
    the two first and last values. The middle bin boundaries are 
    midpoints.

    Example 1: [0, 1] -> [-0.5, 0.5, 1.5]
    Example 2: [0, 1, 4] -> [-0.5, 0.5, 2.5, 5.5]
    Example 3: [4, 1, 0] -> [5.5, 2.5, 0.5, -0.5]"""
    assert index.is_monotonic_increasing or index.is_monotonic_decreasing

    # the beginning and end values are guessed from first and last two
    start = index[0] - (index[1]-index[0])/2
    end = index[-1] + (index[-1]-index[-2])/2

    # the middle values are the midpoints
    middle = pd.DataFrame({'m1': index[:-1], 'p1': index[1:]})
    middle = middle['m1'] + (middle['p1']-middle['m1'])/2

    if isinstance(index, pd.DatetimeIndex):
        idx = pd.DatetimeIndex(middle).union([start,end])
    elif isinstance(index, (pd.Float64Index,pd.RangeIndex,pd.Int64Index)):
        idx = pd.Float64Index(middle).union([start,end])
    else:
        print('Warning: guessing what to do with index type %s' % 
              type(index))
        idx = pd.Float64Index(middle).union([start,end])

    return idx.sort_values(ascending=index.is_monotonic_increasing)

def calc_df_mesh(df):
    """Calculate the two-dimensional bins to hold the index and 
    column values."""
    return np.meshgrid(conv_index_to_bins(df.index),
                       conv_index_to_bins(df.columns))

def heatmap(df):
    """Plot a heatmap of the dataframe values using the index and 
    columns"""
    X,Y = calc_df_mesh(df)
    c = plt.pcolormesh(X, Y, df.values.T)
    plt.colorbar(c)

Call it using heatmap(df), and see it using plt.show().

enter image description here

3 column layout HTML/CSS

.container{
height:100px;
width:500px;
border:2px dotted #F00;
border-left:none;
border-right:none;
text-align:center;
}
.container div{
display: inline-block;
border-left: 2px dotted #ccc;
vertical-align: middle;
line-height: 100px;
} 
 .column-left{ float: left; width: 32%;  height:100px;}
.column-right{ float: right; width: 32%;  height:100px; border-right: 2px dotted #ccc;}
.column-center{ display: inline-block; width: 33%; height:100px;}

 <div class="container">
   <div class="column-left">Column left</div>
   <div class="column-center">Column center</div>
   <div class="column-right">Column right</div>
</div> 

See this link http://jsfiddle.net/bipin_kumar/XD8RW/2/

ERROR 1049 (42000): Unknown database

Its a common error which happens when we try to access a database which doesn't exist. So create the database using

CREATE DATABASE blog_development;

The error commonly occours when we have dropped the database using

DROP DATABASE blog_development;

and then try to access the database.

Add key value pair to all objects in array

arrOfObj.map(o => { 
  o.isActive = true; 
  return o; 
});

How to make the tab character 4 spaces instead of 8 spaces in nano?

For anyone who may stumble across this old question ...

There is one thing that I think needs to be addressed.

~/.nanorc is used to apply your user specific settings to nano, so if you are editing files that require the use of sudo nano for permissions then this is not going to work.

When using sudo your custom user configuration files will not be loaded when opening a program, as you are not running the program from your account so none of your configuration changes in ~/.nanorc will be applied.

If this is the situation you find yourself in (wanting to run sudo nano and use your own config settings) then you have three options :

  • using command line flags when running sudo nano
  • editing the /root/.nanorc file
  • editing the /etc/nanorc global config file

Keep in mind that /etc/nanorc is a global configuration file and as such it affects all users, which may or may not be a problem depending on whether you have a multi-user system.

Also, user config files will override the global one, so if you were to edit /etc/nanorc and ~/.nanorc with different settings, when you run nano it will load the settings from ~/.nanorc but if you run sudo nano then it will load the settings from /etc/nanorc.

Same goes for /root/.nanorc this will override /etc/nanorc when running sudo nano

Using flags is probably the best option unless you have a lot of options.

CSS customized scroll bar in div

Please check this link. Example with working demo

   #style-1::-webkit-scrollbar-track
{
    -webkit-box-shadow: inset 0 0 6px rgba(0,0,0,0.3);
    border-radius: 10px;
    background-color: #F5F5F5;
}

#style-1::-webkit-scrollbar
{
    width: 12px;
    background-color: #F5F5F5;
}

#style-1::-webkit-scrollbar-thumb
{
    border-radius: 10px;
    -webkit-box-shadow: inset 0 0 6px rgba(0,0,0,.3);
    background-color: #555;
}

CSS Scroll Bars

How can I disable the bootstrap hover color for links?

I would go with something like this JSFiddle:

HTML:

<a class="green" href="#">green text</a>
<a class="yellow" href="#">yellow text</a>

CSS:

body  { background: #ccc }
/* Green */
a.green,
a.green:hover { color: green; }
/* Yellow */
a.yellow,
a.yellow:hover { color: yellow; }

What's the meaning of System.out.println in Java?

It is quite simple to understand the question, but to answer it we need to dig deeper in to Java native code.

  • System is static class and cannot be instantiated
  • out is a reference variable defined in System
  • println() is the method used to print on standard output.

A brief and nice explanation is always welcome on this as we can learn much from this single line of statement itself!

Lambda expression to convert array/List of String to array/List of Integers

List<Integer> intList = strList.stream()
                               .map(Integer::valueOf)
                               .collect(Collectors.toList());

WiX tricks and tips

Create a UI that has a custom action that will set a variable and the UI will disable/enable the next button (or similar) based upon the variable set in the custom action.

Not as straight-forward as you would think, not too difficult just not documented anywhere!

Wix Interactions with Conditions, Properties & Custom Actions

The absolute uri: http://java.sun.com/jsp/jstl/core cannot be resolved in either web.xml or the jar files deployed with this application

if you use spring boot check in application.propertiese this property is commented or remove it if exist.

server.tomcat.additional-tld-skip-patterns=*.jar

How do I declare a two dimensional array?

$r = array("arr1","arr2");

to echo a single array element you should write:

echo $r[0];
echo $r[1];

output would be: arr1 arr2

Auto line-wrapping in SVG text

This functionality can also be added using JavaScript. Carto.net has an example:

http://old.carto.net/papers/svg/textFlow/

Something else that also might be useful to are you are editable text areas:

http://old.carto.net/papers/svg/gui/textbox/

Javascript: How to generate formatted easy-to-read JSON straight from an object?

JSON.stringify takes more optional arguments.

Try:

 JSON.stringify({a:1,b:2,c:{d:1,e:[1,2]}}, null, 4); // Indented 4 spaces
 JSON.stringify({a:1,b:2,c:{d:1,e:[1,2]}}, null, "\t"); // Indented with tab

From:

How can I beautify JSON programmatically?

Should work in modern browsers, and it is included in json2.js if you need a fallback for browsers that don't support the JSON helper functions. For display purposes, put the output in a <pre> tag to get newlines to show.

How can I select the row with the highest ID in MySQL?

This is the only proposed method who actually selects the whole row, not only the max(id) field. It uses a subquery

SELECT * FROM permlog WHERE id = ( SELECT MAX( id ) FROM permlog )

What are the advantages of Sublime Text over Notepad++ and vice-versa?

One thing that should be considered is licensing.

Notepad++ is free (as in speech and as in beer) for perpetual use, released under the GPL license, whereas Sublime Text 2 requires a license.

To quote the Sublime Text 2 website:

..a license must be purchased for continued use. There is currently no enforced time limit for the evaluation.

The same is now true of Sublime Text 3, and a paid upgrade will be needed for future versions.

Upgrade Policy A license is valid for Sublime Text 3, and includes all point updates, as well as access to prior versions (e.g., Sublime Text 2). Future major versions, such as Sublime Text 4, will be a paid upgrade.

This licensing requirement is still correct as of Dec 2019.

Display all views on oracle database

for all views (you need dba privileges for this query)

select view_name from dba_views

for all accessible views (accessible by logged user)

select view_name from all_views

for views owned by logged user

select view_name from user_views

SQLite UPSERT / UPDATE OR INSERT

Here's an approach that doesn't require the brute-force 'ignore' which would only work if there was a key violation. This way works based on any conditions you specify in the update.

Try this...

-- Try to update any existing row
UPDATE players
SET age=32
WHERE user_name='steven';

-- If no update happened (i.e. the row didn't exist) then insert one
INSERT INTO players (user_name, age)
SELECT 'steven', 32
WHERE (Select Changes() = 0);

How It Works

The 'magic sauce' here is using Changes() in the Where clause. Changes() represents the number of rows affected by the last operation, which in this case is the update.

In the above example, if there are no changes from the update (i.e. the record doesn't exist) then Changes() = 0 so the Where clause in the Insert statement evaluates to true and a new row is inserted with the specified data.

If the Update did update an existing row, then Changes() = 1 (or more accurately, not zero if more than one row was updated), so the 'Where' clause in the Insert now evaluates to false and thus no insert will take place.

The beauty of this is there's no brute-force needed, nor unnecessarily deleting, then re-inserting data which may result in messing up downstream keys in foreign-key relationships.

Additionally, since it's just a standard Where clause, it can be based on anything you define, not just key violations. Likewise, you can use Changes() in combination with anything else you want/need anywhere expressions are allowed.

Scanner only reads first word instead of line

Use input.nextLine(); instead of input.next();

How to run multiple .BAT files within a .BAT file

using "&"

As you have noticed executing the bat directly without CALL,START, CMD /C causes to enter and execute the first file and then the process to stop as the first file is finished. Though you still can use & which will be the same as using command1 & command2 directly in the console:

(
    first.bat
)&(
    second.bat
)& (
    third.bat
)&(
    echo other commands
)

In a term of machine resources this will be the most efficient way though in the last block you won't be able to use command line GOTO,SHIFT,SETLOCAL.. and its capabilities will almost the same as in executing commands in the command prompt. And you won't be able to execute other command after the last closing bracket

Using CALL

call first.bat
call second.bat
call third.bat

In most of the cases it will be best approach - it does not create a separate process but has almost identical behaviour as calling a :label as subroutine. In MS terminology it creates a new "batch file context and pass control to the statement after the specified label. The first time the end of the batch file is encountered (that is, after jumping to the label), control returns to the statement after the call statement."

You can use variables set in the called files (if they are not set in a SETLOCAL block), you can access directly labels in the called file.

CMD /C, Pipes ,FOR /F

Other native option is to use CMD /C (the /C switch will force the called console to exit and return the control) Something that cmd.exe is doing in non transparent way with using FOR /F against bat file or when pipes are used. This will spawn a child process that will have all the environment ot the calling bat. Less efficient in terms of resources but as the process is separate ,parsing crashes or calling an EXIT command will not stop the calling .bat

@echo off
CMD /c first.bat
CMD /C second.bat

::not so different than the above lines.
:: MORE,FINDSTR,FIND command will be able to read the piped data 
:: passed from the left side

break|third.bat

START

Allows you more flexibility as the capability to start the scripts in separate window , to not wait them to finish, setting a title and so on. By default it starts the .bat and .cmd scripts with CMD /K which means that the spawned scripts will not close automatically.Again passes all the environment to the started scripts and consumes more resources than cmd /c:

:: will be executed in the same console window and will wait to finish
start "" /b /w cmd /c first.bat 

::will start in a separate console window and WONT wait to be finished
:: the second console window wont close automatically so second.bat might need explicit exit command
start "" second.bat

::Will start it in a separate window ,but will wait to finish
:: closing the second window will cause Y/N prompt
:: in the original window 
start "" /w third.cmd


::will start it in the same console window
:: but wont wait to finish. May lead to a little bit confusing output
start "" /b cmd /c fourth.bat

WMIC

Unlike the other methods from now on the examples will use external of the CMD.exe utilities (still available on Windows by default). WMIC utility will create completely separate process so you wont be able directly to wait to finish. Though the best feature of WMIC is that it returns the id of the spawned process:

:: will create a separate process with cmd.exe /c
WMIC process call create "%cd%\first.bat","%cd%"

::you can get the PID and monitoring it with other tools
for /f "tokens=2 delims=;= " %%# in ('WMIC process call create "%cd%\second.bat"^,"%cd%" ^|find "ProcessId"') do (
    set "PID=%%#"
)
echo %PID%

You can also use it to start a process on a remote machine , with different user and so on.

SCHTASKS

Using SCHTASKS provides some features as (obvious) scheduling , running as another user (even the system user) , remote machine start and so on. Again starts it in completely separate environment (i.e. its own variables) and even a hidden process, xml file with command parameters and so on :

SCHTASKS /create /tn BatRunner /tr "%cd%\first.bat" /sc ONCE /sd 01/01/1910 /st 00:00
SCHTASKS /Run /TN BatRunner
SCHTASKS /Delete /TN BatRunner /F

Here the PID also can acquired from the event log.

ScriptRunner

Offers some timeout between started scripts. Basic transaction capabilities (i.e. rollback on error) and the parameters can be put in a separate XML file.

::if the script is not finished after 15 seconds (i.e. ends with pause) it will be killed
ScriptRunner.exe -appvscript %cd%\first.bat -appvscriptrunnerparameters -wait -timeout=15


::will wait or the first called script before to start the second
:: if any of the scripts exit with errorcode different than 0 will try
:: try to restore the system in the original state
ScriptRunner.exe -appvscript second.cmd arg1 arg2 -appvscriptrunnerparameters -wait -rollbackonerror -appvscript third.bat -appvscriptrunnerparameters -wait -timeout=30 -rollbackonerror

How to find the php.ini file used by the command line?

The easiest way nowadays is to use PHP configure:

# php-config --ini-dir
/usr/local/etc/php/7.4/conf.d

There's more you can find there. Example output of the --help sub command (macOS local install):

# php-config --help
Usage: /usr/local/bin/php-config [OPTION]
Options:
  --prefixUsage: /usr/local/bin/php-config [OPTION]
Options:
  --prefix            [/usr/local/Cellar/php/7.4.11]
  --includes          [-I/usr/local/Cellar/php/7.4.11/include/php - …ETC…]
  --ldflags           [ -L/usr/local/Cellar/krb5/1.18.2/lib -…ETC…]
  --libs              [ -ltidy -largon2 …ETC… ]
  --extension-dir     [/usr/local/Cellar/php/7.4.11/pecl/20190902]
  --include-dir       [/usr/local/Cellar/php/7.4.11/include/php]
  --man-dir           [/usr/local/Cellar/php/7.4.11/share/man]
  --php-binary        [/usr/local/Cellar/php/7.4.11/bin/php]
  --php-sapis         [ apache2handler cli fpm phpdbg cgi]
  --ini-path          [/usr/local/etc/php/7.4]
  --ini-dir           [/usr/local/etc/php/7.4/conf.d]
  --configure-options [--prefix=/usr/local/Cellar/php/7.4.11 --…ETC…]
  --version           [7.4.11]
  --vernum            [70411]

List of Python format characters

In docs.python.org Topic = 5.6.2. String Formatting Operations http://docs.python.org/library/stdtypes.html#string-formatting then further down to the chart (text above chart is "The conversion types are:")

The chart lists 16 types and some following notes.

My comment: help does not include attitude which is a bonus. The attitude post enabled me to search further and find the info.

Checking if jquery is loaded using Javascript

Just a small modification that might actually solve the problem:

window.onload = function() {
   if (window.jQuery) {  
       // jQuery is loaded  
       alert("Yeah!");
   } else {
    location.reload();
   }
}

Instead of $(document).Ready(function() use window.onload = function().

Java better way to delete file if exists

file.delete();

if the file doesn't exist, it will return false.

Update span tag value with JQuery

Tag ids must be unique. You are updating the span with ID 'ItemCostSpan' of which there are two. Give the span a class and get it using find.

    $("legend").each(function() {
        var SoftwareItem = $(this).text();
        itemCost = GetItemCost(SoftwareItem);
        $("input:checked").each(function() {               
            var Component = $(this).next("label").text();
            itemCost += GetItemCost(Component);
        });            
        $(this).find(".ItemCostSpan").text("Item Cost = $ " + itemCost);
    });

How do you clear Apache Maven's cache?

I would do the following:

mvn dependency:purge-local-repository -DactTransitively=false -DreResolve=false --fail-at-end

The flags tell maven not to try to resolve dependencies or hit the network. Delete what you see locally.

And for good measure, ignore errors (--fail-at-end) till the very end. This is sometimes useful for projects that have a somewhat messed up set of dependencies or rely on a somewhat messed up internal repository (it happens.)

How to modify a CSS display property from JavaScript?

It should be document.getElementById("hidden").style.display = "block"; not document.getElementById["hidden"].style.display = "block";


EDIT due to author edit:

Why are you using a <div> here? Just add an ID to the table element and add a hidden style to it. E.g. <td id="hidden" style="display:none" class="depot_table_left">

How to create an empty R vector to add new items

In rpy2, the way to get the very same operator as "[" with R is to use ".rx". See the documentation about extracting with rpy2

For creating vectors, if you know your way around with Python there should not be any issue. See the documentation about creating vectors

multiple classes on single element html

It's a good practice if you need them. It's also a good practice is they make sense, so future coders can understand what you're doing.

But generally, no it's not a good practice to attach 10 class names to an object because most likely whatever you're using them for, you could accomplish the same thing with far fewer classes. Probably just 1 or 2.

To qualify that statement, javascript plugins and scripts may append far more classnames to do whatever it is they're going to do. Modernizr for example appends anywhere from 5 - 25 classes to your body tag, and there's a very good reason for it. jQuery UI appends lots of classnames when you use one of the widgets in that library.