Programs & Examples On #Wpas

Confirm password validation in Angular 6

This question could be solved with a combination of these two answers: and

So first of all, you would need a custom validator for checking the passwords, that could look like this:

checkPasswords(group: FormGroup) { // here we have the 'passwords' group
  const password = group.get('password').value;
  const confirmPassword = group.get('confirmPassword').value;

  return password === confirmPassword ? null : { notSame: true }     

and you would create a formgroup for your fields, instead of just two form controls, then mark that custom validator for your form group:

this.myForm ={
  password: ['', [Validators.required]],
  confirmPassword: ['']
}, { validators: this.checkPasswords })

and then as mentioned in other answer, the mat-error only shows if a FormControl is invalid, so you need an error state matcher:

export class MyErrorStateMatcher implements ErrorStateMatcher {
  isErrorState(control: FormControl | null, form: FormGroupDirective | NgForm | null): boolean {
    const invalidCtrl = !!(control?.invalid && control?.parent?.dirty);
    const invalidParent = !!(control?.parent?.invalid && control?.parent?.dirty);

    return invalidCtrl || invalidParent;

in the above you can tweak when to show error message. I would only show message when the password field is touched. Also I would like above, remove the required validator from the confirmPassword field, since the form is not valid anyway if passwords do not match.

Then in component, create a new ErrorStateMatcher:

matcher = new MyErrorStateMatcher();

Finally, the template would look like this:

<form [formGroup]="myForm">
    <input matInput placeholder="New password" formControlName="password" required>
    <mat-error *ngIf="myForm.hasError('required', 'password')">
      Please enter your new password

    <input matInput placeholder="Confirm password" formControlName="confirmPassword" [errorStateMatcher]="matcher">
    <mat-error *ngIf="myForm.hasError('notSame')">
      Passwords do not match

Here's a demo for you with the above code: StackBlitz

MySql ERROR 1045 (28000): Access denied for user 'root'@'localhost' (using password: NO)

For security reason mysql -u root wont work untill you pass -p in command so try with below way

 mysql -u root -p[Enter]
 //enter your localhost password

A connection was successfully established with the server, but then an error occurred during the login process. (Error Number: 233)

To add on top of @Pranav Singh and @Rahul Tripathi answer. After doing all the mentioned by those 2 users, my .net app still wasnt connecting to the database. My solution was.

Open Sql Server Configuration Manager, go to Network configuration of SQL SERVER, click on protocols, right click on TCP/IP and select enabled. I also right clicked on it opened properties, Ip directions, and scrolled to the bottom (IPAII , and there in TCP Port, I did setup a port (1433 is supposed to be default))

Changing an AIX password via script?

In addition to the other suggestions, you can also achieve this using a HEREDOC.

In your immediate case, this might look like:

$ /usr/bin/passwd root <<EOF

SQL Connection Error: System.Data.SqlClient.SqlException (0x80131904)

Check these steps.

  1. go to Sql Server Configuration management->SQL Server network config->protocols for 'servername' and check TCP/IP is enabled.
  2. Open SSMS in run, and check you are able to login to server using specfied username/password and/or using windows authentication.
  3. repeat step 1 for SQL native client config also

Creating lowpass filter in SciPy - understanding methods and units

A few comments:

  • The Nyquist frequency is half the sampling rate.
  • You are working with regularly sampled data, so you want a digital filter, not an analog filter. This means you should not use analog=True in the call to butter, and you should use scipy.signal.freqz (not freqs) to generate the frequency response.
  • One goal of those short utility functions is to allow you to leave all your frequencies expressed in Hz. You shouldn't have to convert to rad/sec. As long as you express your frequencies with consistent units, the scaling in the utility functions takes care of the normalization for you.

Here's my modified version of your script, followed by the plot that it generates.

import numpy as np
from scipy.signal import butter, lfilter, freqz
import matplotlib.pyplot as plt

def butter_lowpass(cutoff, fs, order=5):
    nyq = 0.5 * fs
    normal_cutoff = cutoff / nyq
    b, a = butter(order, normal_cutoff, btype='low', analog=False)
    return b, a

def butter_lowpass_filter(data, cutoff, fs, order=5):
    b, a = butter_lowpass(cutoff, fs, order=order)
    y = lfilter(b, a, data)
    return y

# Filter requirements.
order = 6
fs = 30.0       # sample rate, Hz
cutoff = 3.667  # desired cutoff frequency of the filter, Hz

# Get the filter coefficients so we can check its frequency response.
b, a = butter_lowpass(cutoff, fs, order)

# Plot the frequency response.
w, h = freqz(b, a, worN=8000)
plt.subplot(2, 1, 1)
plt.plot(0.5*fs*w/np.pi, np.abs(h), 'b')
plt.plot(cutoff, 0.5*np.sqrt(2), 'ko')
plt.axvline(cutoff, color='k')
plt.xlim(0, 0.5*fs)
plt.title("Lowpass Filter Frequency Response")
plt.xlabel('Frequency [Hz]')

# Demonstrate the use of the filter.
# First make some data to be filtered.
T = 5.0         # seconds
n = int(T * fs) # total number of samples
t = np.linspace(0, T, n, endpoint=False)
# "Noisy" data.  We want to recover the 1.2 Hz signal from this.
data = np.sin(1.2*2*np.pi*t) + 1.5*np.cos(9*2*np.pi*t) + 0.5*np.sin(12.0*2*np.pi*t)

# Filter the data, and plot both the original and filtered signals.
y = butter_lowpass_filter(data, cutoff, fs, order)

plt.subplot(2, 1, 2)
plt.plot(t, data, 'b-', label='data')
plt.plot(t, y, 'g-', linewidth=2, label='filtered data')
plt.xlabel('Time [sec]')


lowpass example

System.Data.SqlClient.SqlException: Login failed for user

Just set Integrated Security=False and it will work ,according to a comment difference between True and False is:

True ignores User ID and Password if provided and uses those of the running process, SSPI(Security Support Provider Interface ) it will use them if provided which is why MS prefers this. They are equivalent in that they use the same security mechanism to authenticate but that is it.

"The system cannot find the file specified"

I got this error when starting my ASP.NET application and in my case the problem was that the SQL Server service was not running. Starting that cleared it up.

C# Inserting Data from a form into an access Database

This answer will help in case, If you are working with Data Bases then mostly take the help of try-catch block statement, which will help and guide you with your code. Here i am showing you that how to insert some values in Data Base with a Button Click Event.

 private void button2_Click(object sender, EventArgs e)
        System.Data.OleDb.OleDbConnection conn = new System.Data.OleDb.OleDbConnection();
        conn.ConnectionString = @"Provider=Microsoft.ACE.OLEDB.12.0;" +
    @"Data source= C:\Users\pir fahim shah\Documents\TravelAgency.accdb";

           String ticketno=textBox1.Text.ToString();                 
           String Purchaseprice=textBox2.Text.ToString();
           String sellprice=textBox3.Text.ToString();
           String my_querry = "INSERT INTO Table1(TicketNo,Sellprice,Purchaseprice)VALUES('"+ticketno+"','"+sellprice+"','"+Purchaseprice+"')";

            OleDbCommand cmd = new OleDbCommand(my_querry, conn);

            MessageBox.Show("Data saved successfuly...!");
         catch (Exception ex)
             MessageBox.Show("Failed due to"+ex.Message);

How to use new PasswordEncoder from Spring Security

I had a similar issue. I needed to keep the legacy encrypted passwords (Base64/SHA-1/Random salt Encoded) as users will not want to change their passwords or re-register. However I wanted to use the BCrypt encoder moving forward too.

My solution was to write a bespoke decoder that checks to see which encryption method was used first before matching (BCrypted ones start with $).

To get around the salt issue, I pass into the decoder a concatenated String of salt + encrypted password via my modified user object.


public class LegacyEncoder implements PasswordEncoder {

    private static final String BCRYP_TYPE = "$";
    private static final PasswordEncoder BCRYPT = new BCryptPasswordEncoder();

    public String encode(CharSequence rawPassword) {

    return BCRYPT.encode(rawPassword);

    public boolean matches(CharSequence rawPassword, String encodedPassword) {

    if (encodedPassword.startsWith(BCRYP_TYPE)) {
        return BCRYPT.matches(rawPassword, encodedPassword);

    return sha1SaltMatch(rawPassword, encodedPassword);

    private boolean sha1SaltMatch(CharSequence rawPassword, String encodedPassword) {

    String[] saltHash = encodedPassword.split(User.SPLIT_CHAR);

    // Legacy code from old system   
    byte[] b64salt = Base64.getDecoder().decode(saltHash[0].getBytes());
    byte[] validHash = Base64.getDecoder().decode(saltHash[1]);
    byte[] checkHash = Utility.getHash(5, rawPassword.toString(), b64salt);

    return Arrays.equals(checkHash, validHash);


User Object

public class User implements UserDetails {

    public static final String SPLIT_CHAR = ":";

    @Column(name = "user_id", nullable = false)
    private Integer userId;

    @Column(nullable = false, length = 60)
    private String password;

    @Column(nullable = true, length = 32)
    private String salt;


    private void init() {

    username = emailAddress; //To comply with UserDetails
    password = salt == null ? password : salt + SPLIT_CHAR + password;

You can also add a hook to re-encode the password in the new BCrypt format and replace it. Thus phasing out the old method.

A network-related or instance-specific error occurred while establishing a connection to SQL Server

Sql Server fire this error when your application don't have enough rights to access the database. there are several reason about this error . To fix this error you should follow the following instruction.

  1. Try to connect sql server from your server using management studio . if you use windows authentication to connect sql server then set your application pool identity to server administrator .

  2. if you use sql server authentication then check you connection string in web.config of your web application and set user id and password of sql server which allows you to log in .

  3. if your database in other server(access remote database) then first of enable remote access of sql server form sql server property from sql server management studio and enable TCP/IP form sql server configuration manager .

  4. after doing all these stuff and you still can't access the database then check firewall of server form where you are trying to access the database and add one rule in firewall to enable port of sql server(by default sql server use 1433 , to check port of sql server you need to check sql server configuration manager network protocol TCP/IP port).

  5. if your sql server is running on named instance then you need to write port number with sql serer name for example 117.312.21.21/nameofsqlserver,1433.

  6. If you are using cloud hosting like amazon aws or microsoft azure then server or instance will running behind cloud firewall so you need to enable 1433 port in cloud firewall if you have default instance or specific port for sql server for named instance.

  7. If you are using amazon RDS or SQL azure then you need to enable port from security group of that instance.

  8. If you are accessing sql server through sql server authentication mode them make sure you enabled "SQL Server and Windows Authentication Mode" sql server instance property. enter image description here

    1. Restart your sql server instance after making any changes in property as some changes will require restart.

if you further face any difficulty then you need to provide more information about your web site and sql server .

ERROR 1049 (42000): Unknown database

blog_development doesn't exist

You can see this in sql by the 0 rows affected message

create it in mysql with

mysql> create database blog_development

However as you are using rails you should get used to using

$ rake db:create

to do the same task. It will use your database.yml file settings, which should include something like:

  adapter: mysql2
  database: blog_development
  pool: 5

Also become familiar with:

$ rake db:migrate  # Run the database migration
$ rake db:seed     # Run thew seeds file create statements
$ rake db:drop     # Drop the database

Javascript regular expression password validation having special characters

If you check the length seperately, you can do the following:

var regularExpression  = /^[a-zA-Z]$/;

if (regularExpression.test(newPassword)) {
    alert("password should contain atleast one number and one special character");
    return false;

Add Custom Headers using HttpWebRequest

You should do ex.StackTrace instead of ex.ToString()

Checking password match while typing

Probably invalid syntax in your onChange event, I avoid using like this (within the html) as I think it is messy and it is hard enough keeping JavaScript tidy at the best of times.

I would rather register the event on the document ready event in javascript. You will also definitely want to use keyup event too if you want the validation as the user is typing:

$(document).ready(function () {

Here is a working example

Personally I would prefer to do the check when either password field changes, that way if they re-type the original password then you still get the same validation check:

$(document).ready(function () {
   $("#txtNewPassword, #txtConfirmPassword").keyup(checkPasswordMatch);

Here is a working example

Enable tcp\ip remote connections to sql server express already installed database with code or script(query)

I tested below code with SQL Server 2008 R2 Express and I believe we should have solution for all 6 steps you outlined. Let's take on them one-by-one:

1 - Enable TCP/IP

We can enable TCP/IP protocol with WMI:

set wmiComputer = GetObject( _
    "winmgmts:" _
    & "\\.\root\Microsoft\SqlServer\ComputerManagement10")
set tcpProtocols = wmiComputer.ExecQuery( _
    "select * from ServerNetworkProtocol " _
    & "where InstanceName = 'SQLEXPRESS' and ProtocolName = 'Tcp'")

if tcpProtocols.Count = 1 then
    ' set tcpProtocol = tcpProtocols(0)
    ' I wish this worked, but unfortunately 
    ' there's no int-indexed Item property in this type

    ' Doing this instead
    for each tcpProtocol in tcpProtocols
        dim setEnableResult
            setEnableResult = tcpProtocol.SetEnable()
            if setEnableResult <> 0 then 
                Wscript.Echo "Failed!"
            end if
end if

2 - Open the right ports in the firewall

I believe your solution will work, just make sure you specify the right port. I suggest we pick a different port than 1433 and make it a static port SQL Server Express will be listening on. I will be using 3456 in this post, but please pick a different number in the real implementation (I feel that we will see a lot of applications using 3456 soon :-)

3 - Modify TCP/IP properties enable a IP address

We can use WMI again. Since we are using static port 3456, we just need to update two properties in IPAll section: disable dynamic ports and set the listening port to 3456:

set wmiComputer = GetObject( _
    "winmgmts:" _
    & "\\.\root\Microsoft\SqlServer\ComputerManagement10")
set tcpProperties = wmiComputer.ExecQuery( _
    "select * from ServerNetworkProtocolProperty " _
    & "where InstanceName='SQLEXPRESS' and " _
    & "ProtocolName='Tcp' and IPAddressName='IPAll'")

for each tcpProperty in tcpProperties
    dim setValueResult, requestedValue

    if tcpProperty.PropertyName = "TcpPort" then
        requestedValue = "3456"
    elseif tcpProperty.PropertyName ="TcpDynamicPorts" then
        requestedValue = ""
    end if

    setValueResult = tcpProperty.SetStringValue(requestedValue)
    if setValueResult = 0 then 
        Wscript.Echo "" & tcpProperty.PropertyName & " set."
        Wscript.Echo "" & tcpProperty.PropertyName & " failed!"
    end if

Note that I didn't have to enable any of the individual addresses to make it work, but if it is required in your case, you should be able to extend this script easily to do so.

Just a reminder that when working with WMI, WBEMTest.exe is your best friend!

4 - Enable mixed mode authentication in sql server

I wish we could use WMI again, but unfortunately this setting is not exposed through WMI. There are two other options:

  1. Use LoginMode property of Microsoft.SqlServer.Management.Smo.Server class, as described here.

  2. Use LoginMode value in SQL Server registry, as described in this post. Note that by default the SQL Server Express instance is named SQLEXPRESS, so for my SQL Server 2008 R2 Express instance the right registry key was HKEY_LOCAL_MACHINE\SOFTWARE\Microsoft\Microsoft SQL Server\MSSQL10_50.SQLEXPRESS\MSSQLServer.

5 - Change user (sa) default password

You got this one covered.

6 - Finally (connect to the instance)

Since we are using a static port assigned to our SQL Server Express instance, there's no need to use instance name in the server address anymore.

SQLCMD -U sa -P newPassword -S,3456

Please let me know if this works for you (fingers crossed!).

grant remote access of MySQL database from any IP address

Open your mysql console and execute the following command (enter your database name,username and password):

GRANT ALL ON yourdatabasename.* TO admin@'%' IDENTIFIED BY 'yourRootPassword';

Then Execute:


Open command line and open the file /etc/mysql/mysql.conf.d/mysqld.cnf using any editor with root privileges.

For example:

sudo nano /etc/mysql/mysql.conf.d/mysqld.cnf

Then comment out the below line:

bind-address =

Restart mysql to reflect the changes using command:

sudo service mysql restart

Enjoy ;)

How can I insert data into a MySQL database?

This way worked for me when adding random data to MySql table using a python script.
First install the following packages using the below commands

pip install mysql-connector-python<br>
pip install random
import mysql.connector
import random

from datetime import date

start_dt =, month=1).toordinal()
end_dt =

mydb = mysql.connector.connect(

mycursor = mydb.cursor()

sql_insertion = "INSERT INTO customer (name,email,address,dateJoined) VALUES (%s, %s,%s, %s)"
#insert 10 records(rows)
for x in range(1,11):
    #generate a random date
    random_day = date.fromordinal(random.randint(start_dt, end_dt))
    value = ("customer" + str(x),"customer_email" + str(x),"customer_address" + str(x),random_day)
    mycursor.execute(sql_insertion , value)


print("customer records inserted!")

Following is a sample output of the insertion

cid       |  name      |  email           |    address        |  dateJoined  |

1         | customer1  |  customer_email1 | customer_address1 |  2020-11-15  |
2         | customer2  |  customer_email2 | customer_address2 |  2020-10-11  |
3         | customer3  |  customer_email3 | customer_address3 |  2020-11-17  |
4         | customer4  |  customer_email4 | customer_address4 |  2020-09-20  |
5         | customer5  |  customer_email5 | customer_address5 |  2020-02-18  |
6         | customer6  |  customer_email6 | customer_address6 |  2020-01-11  |
7         | customer7  |  customer_email7 | customer_address7 |  2020-05-30  |
8         | customer8  |  customer_email8 | customer_address8 |  2020-04-22  |
9         | customer9  |  customer_email9 | customer_address9 |  2020-01-05  |
10        | customer10 |  customer_email10| customer_address10|  2020-11-12  |

matching query does not exist Error in Django

You can use this in your case, it will work fine.

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

How to connect to a secure website using SSL in Java with a pkcs12 file?

URL url = new URL("https://test.domain:443");   
String  keyStore = "server.p12"
String   keyStorePassword = "changeit";    
String  keyPassword = "changeit";    
String   KeyStoreType= "PKCS12";    
String   KeyManagerAlgorithm = "SunX509";    
String   SSLVersion = "SSLv3";    
public HttpURLConnection getHttpsURLConnection(URL url, String  keystore,
    String   keyStorePass,String  keyPassword, String  KeyStoreType
    ,String KeyManagerAlgorithm, String  SSLVersion)
    throws NoSuchAlgorithmException, KeyStoreException,
        CertificateException, FileNotFoundException, IOException,
        UnrecoverableKeyException, KeyManagementException {

    SSLContext sslcontext = SSLContext.getInstance(SSLVersion);
    KeyManagerFactory kmf =  KeyManagerFactory.getInstance(KeyManagerAlgorithm);
    KeyStore ks = KeyStore.getInstance(KeyStoreType);
    ks.load(new FileInputStream(keystore), keyStorePass.toCharArray());
    kmf.init(ks, keyPassword.toCharArray());

     TrustManagerFactory tmf = TrustManagerFactory
    TrustManager[] tm = tmf.getTrustManagers();

    sslcontext.init(kmf.getKeyManagers(), tm, null);
    SSLSocketFactory sslSocketFactory = sslcontext.getSocketFactory();
    HttpsURLConnection httpsURLConnection = ( HttpsURLConnection)uRL.openConnection();

    return httpsURLConnection;

How to display my application's errors in JSF?

Found this while Googling. The second post makes a point about the different phases of JSF, which might be causing your error message to become lost. Also, try null in place of "newPassword" because you do not have any object with the id newPassword.

How do I override nested NPM dependency versions?

You can use npm shrinkwrap functionality, in order to override any dependency or sub-dependency.

I've just done this in a grunt project of ours. We needed a newer version of connect, since 2.7.3. was causing trouble for us. So I created a file named npm-shrinkwrap.json:

  "dependencies": {
    "grunt-contrib-connect": {
      "version": "0.3.0",
      "from": "[email protected]",
      "dependencies": {
        "connect": {
          "version": "2.8.1",
          "from": "connect@~2.7.3"

npm should automatically pick it up while doing the install for the project.


Get the position of a spinner in Android

if (position ==0) {
    if (rYes.isChecked()) {
        Toast.makeText(SportActivity.this, "yes ur answer is right", Toast.LENGTH_LONG).show();
    } else if (rNo.isChecked()) {
        Toast.makeText(SportActivity.this, "no.ur answer is wrong", Toast.LENGTH_LONG).show();

This code is supposed to select both check boxes.
Is there a problem with it?

Git merge with force overwrite

Not really related to this answer, but I'd ditch git pull, which just runs git fetch followed by git merge. You are doing three merges, which is going to make your Git run three fetch operations, when one fetch is all you will need. Hence:

git fetch origin   # update all our origin/* remote-tracking branches

git checkout demo         # if needed -- your example assumes you're on it
git merge origin/demo     # if needed -- see below

git checkout master
git merge origin/master

git merge -X theirs demo   # but see below

git push origin master     # again, see below

Controlling the trickiest merge

The most interesting part here is git merge -X theirs. As root545 noted, the -X options are passed on to the merge strategy, and both the default recursive strategy and the alternative resolve strategy take -X ours or -X theirs (one or the other, but not both). To understand what they do, though, you need to know how Git finds, and treats, merge conflicts.

A merge conflict can occur within some file1 when the base version differs from both the current (also called local, HEAD, or --ours) version and the other (also called remote or --theirs) version of that same file. That is, the merge has identified three revisions (three commits): base, ours, and theirs. The "base" version is from the merge base between our commit and their commit, as found in the commit graph (for much more on this, see other StackOverflow postings). Git has then found two sets of changes: "what we did" and "what they did". These changes are (in general) found on a line-by-line, purely textual basis. Git has no real understanding of file contents; it is merely comparing each line of text.

These changes are what you see in git diff output, and as always, they have context as well. It's possible that things we changed are on different lines from things they changed, so that the changes seem like they would not collide, but the context has also changed (e.g., due to our change being close to the top or bottom of the file, so that the file runs out in our version, but in theirs, they have also added more text at the top or bottom).

If the changes happen on different lines—for instance, we change color to colour on line 17 and they change fred to barney on line 71—then there is no conflict: Git simply takes both changes. If the changes happen on the same lines, but are identical changes, Git takes one copy of the change. Only if the changes are on the same lines, but are different changes, or that special case of interfering context, do you get a modify/modify conflict.

The -X ours and -X theirs options tell Git how to resolve this conflict, by picking just one of the two changes: ours, or theirs. Since you said you are merging demo (theirs) into master (ours) and want the changes from demo, you would want -X theirs.

Blindly applying -X, however, is dangerous. Just because our changes did not conflict on a line-by-line basis does not mean our changes do not actually conflict! One classic example occurs in languages with variable declarations. The base version might declare an unused variable:

int i;

In our version, we delete the unused variable to make a compiler warning go away—and in their version, they add a loop some lines later, using i as the loop counter. If we combine the two changes, the resulting code no longer compiles. The -X option is no help here since the changes are on different lines.

If you have an automated test suite, the most important thing to do is to run the tests after merging. You can do this after committing, and fix things up later if needed; or you can do it before committing, by adding --no-commit to the git merge command. We'll leave the details for all of this to other postings.

1You can also get conflicts with respect to "file-wide" operations, e.g., perhaps we fix the spelling of a word in a file (so that we have a change), and they delete the entire file (so that they have a delete). Git will not resolve these conflicts on its own, regardless of -X arguments.

Doing fewer merges and/or smarter merges and/or using rebase

There are three merges in both of our command sequences. The first is to bring origin/demo into the local demo (yours uses git pull which, if your Git is very old, will fail to update origin/demo but will produce the same end result). The second is to bring origin/master into master.

It's not clear to me who is updating demo and/or master. If you write your own code on your own demo branch, and others are writing code and pushing it to the demo branch on origin, then this first-step merge can have conflicts, or produce a real merge. More often than not, it's better to use rebase, rather than merge, to combine work (admittedly, this is a matter of taste and opinion). If so, you might want to use git rebase instead. On the other hand, if you never do any of your own commits on demo, you don't even need a demo branch. Alternatively, if you want to automate a lot of this, but be able to check carefully when there are commits that both you and others, made, you might want to use git merge --ff-only origin/demo: this will fast-forward your demo to match the updated origin/demo if possible, and simply outright fail if not (at which point you can inspect the two sets of changes, and choose a real merge or a rebase as appropriate).

This same logic applies to master, although you are doing the merge on master, so you definitely do need a master. It is, however, even likelier that you would want the merge to fail if it cannot be done as a fast-forward non-merge, so this probably also should be git merge --ff-only origin/master.

Let's say that you never do your own commits on demo. In this case we can ditch the name demo entirely:

git fetch origin   # update origin/*

git checkout master
git merge --ff-only origin/master || die "cannot fast-forward our master"

git merge -X theirs origin/demo || die "complex merge conflict"

git push origin master

If you are doing your own demo branch commits, this is not helpful; you might as well keep the existing merge (but maybe add --ff-only depending on what behavior you want), or switch it to doing a rebase. Note that all three methods may fail: merge may fail with a conflict, merge with --ff-only may not be able to fast-forward, and rebase may fail with a conflict (rebase works by, in essence, cherry-picking commits, which uses the merge machinery and hence can get a merge conflict).

How to add a title to a html select tag

You can add an option tag on top of the others with no value and a prompt like this:

        <option value="">Choose One</option>
        <option value ="sydney">Sydney</option>
        <option value ="melbourne">Melbourne</option>
        <option value ="cromwell">Cromwell</option>
        <option value ="queenstown">Queenstown</option>

Or leave it blank instead of saying Choose one if you want.

Using import fs from 'fs'

For default exports you should use:

import * as fs from 'fs';

Or in case the module has named exports:

import {fs} from 'fs';



export function function1() {

export function function2() {

export default function1;

And then:

import defaultExport, { function1, function2 } from './module1'

defaultExport();  // This calls function1

Additionally, you should use Webpack or something similar to be able to use ES6 import

How to cast an Object to an int

I use a one-liner when processing data from GSON:

int i = object != null ? Double.valueOf(object.toString()).intValue() : 0;

Get decimal portion of a number with JavaScript

Floating-point decimal sign and number format can be dependent from country (.,), so independent solution, which preserved floating point part, is:

getFloatDecimalPortion = function(x) {
    x = Math.abs(parseFloat(x));
    let n = parseInt(x);
    return Number((x - n).toFixed(Math.abs((""+x).length - (""+n).length - 1)));

– it is internationalized solution, instead of location-dependent:

getFloatDecimalPortion = x => parseFloat("0." + ((x + "").split(".")[1]));

Solution desription step by step:

  1. parseFloat() for guaranteeing input cocrrection
  2. Math.abs() for avoiding problems with negative numbers
  3. n = parseInt(x) for getting decimal part
  4. x - n for substracting decimal part
  5. We have now number with zero decimal part, but JavaScript could give us additional floating part digits, which we do not want
  6. So, limit additional digits by calling toFixed() with count of digits in floating part of original float number x. Count is calculated as difference between length of original number x and number n in their string representation.

groovy.lang.MissingPropertyException: No such property: jenkins for class: groovy.lang.Binding

Please double check that jenkins is not blocking this import. Go to script approvals and check to see if it is blocking it. If it is click allow.

How do I pass a URL with multiple parameters into a URL?

In your example parts of your passed-in URL are not URL encoded (for example the colon should be %3A, the forward slashes should be %2F). It looks like you have encoded the parameters to your parameter URL, but not the parameter URL itself. Try encoding it as well. You can use encodeURIComponent.

Different color for each bar in a bar chart; ChartJS

As of August 2019, Chart.js now has this functionality built in.

Successful bar chart with different colored bars

You simply need to provide an array to backgroundColor.

Example taken from


  data: {
        labels: ['January', 'February', 'March', 'April', 'May', 'June', 'July'],
        datasets: [{
            label: 'My First dataset',
            backgroundColor: 'rgb(255, 99, 132)',
            borderColor: 'rgb(255, 99, 132)',
            data: [0, 10, 5, 2, 20, 30, 45]


  data: {
        labels: ['January', 'February', 'March', 'April', 'May', 'June', 'July'],
        datasets: [{
            label: 'My First dataset',
            backgroundColor: ['rgb(255, 99, 132)','rgb(0, 255, 0)','rgb(255, 99, 132)','rgb(128, 255, 0)','rgb(0, 255, 255)','rgb(255, 255, 0)','rgb(255, 255, 128)'],
            borderColor: 'rgb(255, 99, 132)',
            data: [0, 10, 5, 2, 20, 30, 45]

I just tested this method and it works. Each bar has a different color.

TypeError: $ is not a function when calling jQuery function

replace $ sign with jQuery like this:

//your code here

Is there a 'foreach' function in Python 3?

Yes, although it uses the same syntax as a for loop.

for x in ['a', 'b']: print(x)

Swift Beta performance: sorting arrays

The main issue that is mentioned by others but not called out enough is that -O3 does nothing at all in Swift (and never has) so when compiled with that it is effectively non-optimised (-Onone).

Option names have changed over time so some other answers have obsolete flags for the build options. Correct current options (Swift 2.2) are:

-Onone // Debug - slow
-O     // Optimised
-O -whole-module-optimization //Optimised across files

Whole module optimisation has a slower compile but can optimise across files within the module i.e. within each framework and within the actual application code but not between them. You should use this for anything performance critical)

You can also disable safety checks for even more speed but with all assertions and preconditions not just disabled but optimised on the basis that they are correct. If you ever hit an assertion this means that you are into undefined behaviour. Use with extreme caution and only if you determine that the speed boost is worthwhile for you (by testing). If you do find it valuable for some code I recommend separating that code into a separate framework and only disabling the safety checks for that module.

javascript create array from for loop

You need to push i

var yearStart = 2000;
var yearEnd = 2040;

var arr = [];

for (var i = yearStart; i < yearEnd+1; i++) {

Then, your resulting array will be:

arr = [2000, 2001, 2003, ... 2039, 2040]

Hope this helps

is there a 'block until condition becomes true' function in java?

You could use a semaphore.

While the condition is not met, another thread acquires the semaphore.
Your thread would try to acquire it with acquireUninterruptibly()
or tryAcquire(int permits, long timeout, TimeUnit unit) and would be blocked.

When the condition is met, the semaphore is also released and your thread would acquire it.

You could also try using a SynchronousQueue or a CountDownLatch.

How do I trim() a string in angularjs?

Why don't you simply use JavaScript's trim():

str.trim() //Will work everywhere irrespective of any framework.

For compatibility with <IE9 use:

if(typeof String.prototype.trim !== 'function') {
  String.prototype.trim = function() {
    return this.replace(/^\s+|\s+$/g, ''); 

Found it Here

Align button at the bottom of div using CSS

Parent container has to have this:

position: relative;

Button itself has to have this:

position: relative;
bottom: 20px;
right: 20px;

or whatever you like

What is a word boundary in regex, does \b match hyphen '-'?

In the course of learning regular expression, I was really stuck in the metacharacter which is \b. I indeed didn't comprehend its meaning while I was asking myself "what it is, what it is" repetitively. After some attempts by using the website, I watch out the pink vertical dashes at the every beginning of words and at the end of words. I got it its meaning well at that time. It's now exactly word(\w)-boundary.

My view is merely to immensely understanding-oriented. Logic behind of it should be examined from another answers.

enter image description here

How do I create a foreign key in SQL Server?

Like you, I don't usually create foreign keys by hand, but if for some reason I need the script to do so I usually create it using ms sql server management studio and before saving then changes, I select Table Designer | Generate Change Script

Remove columns from dataframe where ALL values are NA

The two approaches offered thus far fail with large data sets as (amongst other memory issues) they create, which will be an object the same size as df.

Here are two approaches that are more memory and time efficient

An approach using Filter

Filter(function(x)!all(, df)

and an approach using data.table (for general time and memory efficiency)

DT <-
DT[,which(unlist(lapply(DT, function(x)!all(,with=F]

examples using large data (30 columns, 1e6 rows)

big_data <- replicate(10, data.frame(rep(NA, 1e6), sample(c(1:8,NA),1e6,T), sample(250,1e6,T)),simplify=F)
bd <-,big_data)
names(bd) <- paste0('X',seq_len(30))
DT <-

system.time({df1 <- bd[,colSums( < nrow(bd))]})
# error -- can't allocate vector of size ...
system.time({df2 <- bd[, !apply(, 2, all)]})
# error -- can't allocate vector of size ...
system.time({df3 <- Filter(function(x)!all(, bd)})
## user  system elapsed 
## 0.26    0.03    0.29 
system.time({DT1 <- DT[,which(unlist(lapply(DT, function(x)!all(,with=F]})
## user  system elapsed 
## 0.14    0.03    0.18 

How does "FOR" work in cmd batch file?

for /f iterates per line input, so in your program will only output first path.

your program treats %PATH% as one-line input, and deliminate by ;, put first result to %%g, then output %%g (first deliminated path).

Copy all values in a column to a new column in a pandas dataframe

The problem is in the line before the one that throws the warning. When you create df_2 that's where you're creating a copy of a slice of a dataframe. Instead, when you create df_2, use .copy() and you won't get that warning later on.

df_2 = df[df['B'] == 'b.2'].copy()

How to set border's thickness in percentages?

Modern browsers support vh and vw units, which are a percentage of the window viewport.

So you can have pure CSS borders as a percentage of the window size:

border: 5vw solid red;

Try this example and change window width; the border will change thickness as the window changes size. box-sizing: border-box; may be useful too.

Read from database and fill DataTable

Private Function LoaderData(ByVal strSql As String) As DataTable
    Dim cnn As SqlConnection
    Dim dad As SqlDataAdapter

    Dim dtb As New DataTable
    cnn = New SqlConnection(My.Settings.mySqlConnectionString)
        dad = New SqlDataAdapter(strSql, cnn)
    Catch ex As Exception
    End Try
    Return dtb
End Function

What is the difference between %g and %f in C?

See any reference manual, such as the man page:


The double argument is rounded and converted to decimal notation in the style [-]ddd.ddd, where the number of digits after the decimal-point character is equal to the precision specification. If the precision is missing, it is taken as 6; if the precision is explicitly zero, no decimal-point character appears. If a decimal point appears, at least one digit appears before it. (The SUSv2 does not know about F and says that character string representations for infinity and NaN may be made available. The C99 standard specifies '[-]inf' or '[-]infinity' for infinity, and a string starting with 'nan' for NaN, in the case of f conversion, and '[-]INF' or '[-]INFINITY' or 'NAN*' in the case of F conversion.)


The double argument is converted in style f or e (or F or E for G conversions). The precision specifies the number of significant digits. If the precision is missing, 6 digits are given; if the precision is zero, it is treated as 1. Style e is used if the exponent from its conversion is less than -4 or greater than or equal to the precision. Trailing zeros are removed from the fractional part of the result; a decimal point appears only if it is followed by at least one digit.

How to get out of while loop in java with Scanner method "hasNext" as condition?

You can simply use one of the system dependent end-of-file indicators ( d for Unix/Linux/Ubuntu, z for windows) to make the while statement false. This should get you out of the loop nicely. :)

C++ Calling a function from another class

What you should do, is put CallFunction into *.cpp file, where you include B.h.

After edit, files will look like:


#pragma once //or other specific to compiler...
using namespace std;

class A 
    void CallFunction ();

class B: public A
    virtual void bFunction()
            //stuff done here


#include "B.h"
void A::CallFunction(){
//use B object here...

Referencing to your explanation, that you have tried to change B b; into pointer- it would be okay, if you wouldn't use it in that same place. You can use pointer of undefined class(but declared), because ALL pointers have fixed byte size(4), so compiler doesn't have problems with that. But it knows nothing about the object they are pointing to(simply: knows the size/boundary, not the content).

So as long as you are using the knowledge, that all pointers are same size, you can use them anywhere. But if you want to use the object, they are pointing to, the class of this object must be already defined and known by compiler.

And last clarification: objects may differ in size, unlike pointers. Pointer is a number/index, which indicates the place in RAM, where something is stored(for example index: 0xf6a7b1).

Passing HTML input value as a JavaScript Function Parameter

   <form action="" onsubmit="additon()" name="form1" id="form1">
      a: <input type="number" name="a" id="a"><br>
      b: <input type="number" name="b" id="b"><br>
      <input type="submit" value="Submit" name="submit">
      function additon() 
           var a = document.getElementById('a').value;
           var b = document.getElementById('b').value;
           var sum = parseInt(a) + parseInt(b);
           return sum;

"Android library projects cannot be launched"?

It says “Android library projects cannot be launched” because Android library projects cannot be launched. That simple. You cannot run a library. If you want to test a library, create an Android project that uses the library, and execute it.

Is it possible to run JavaFX applications on iOS, Android or Windows Phone 8?

Desktop: first-class support

Oracle JavaFX from Java SE supports only OS X (macOS), GNU/Linux and Microsoft Windows. On these platforms, JavaFX applications are typically run on JVM from Java SE or OpenJDK.

Android: should work

There is also a JavaFXPorts project, which is an open-source project sponsored by a third-party. It aims to port JavaFX library to Android and iOS.

On Android, this library can be used like any other Java library; the JVM bytecode is compiled to Dalvik bytecode. It's what people mean by saying that "Android runs Java".

iOS: status not clear

On iOS, situation is a bit more complex, as neither Java SE nor OpenJDK supports Apple mobile devices. Till recently, the only sensible option was to use RoboVM ahead-of-time Java compiler for iOS. Unfortunately, on 15 April 2015, RoboVM project was shut down.

One possible alternative is Intel's Multi-OS Engine. Till recently, it was a proprietary technology, but on 11 August 2016 it was open-sourced. Although it can be possible to compile an iOS JavaFX app using JavaFXPorts' JavaFX implementation, there is no evidence for that so far. As you can see, the situation is dynamically changing, and this answer will be hopefully updated when new information is available.

Windows Phone: no support

With Windows Phone it's simple: there is no JavaFX support of any kind.

Disabling browser caching for all browsers from ASP.NET

See also How to prevent google chrome from caching my inputs, esp hidden ones when user click back? without which Chrome might reload but preserve the previous content of <input> elements -- in other words, use autocomplete="off".

Visually managing MongoDB documents and collections

I use MongoVUE, it's good for viewing data, but there is almost no editing abilities.


You have to override your ; delimiter with something like $$ to avoid this kind of error.

After your function definition, you can set the delimiter back to ;.

This should work:

CREATE FUNCTION F_Dist3D (x1 decimal, y1 decimal) 
RETURNS decimal
  DECLARE dist decimal;
  SET dist = SQRT(x1 - y1);
  RETURN dist;

Is there a way to catch the back button event in javascript?

Use the hashchange event:

window.addEventListener("hashchange", function(e) {
  // ...

If you need to support older browsers, check out the hashChange Event section in Modernizr's HTML5 Cross Browser Polyfills wiki page.

stdlib and colored output in C

You can assign one color to every functionality to make it more useful.

#define Color_Red "\33[0:31m\\]" // Color Start
#define Color_end "\33[0m\\]" // To flush out prev settings
#define LOG_RED(X) printf("%s %s %s",Color_Red,X,Color_end)

LOG_RED("This is in Red Color");

Like wise you can select different color codes and make this more generic.

Put icon inside input element in a form

 <label for="fileEdit">
    <i class="fa fa-cloud-upload">
    <input id="fileEdit" class="hidden" type="file" name="addImg" ng-file-change="onImageChange( $files )" ng-multiple="false" accept="{{ contentType }}"/>

For example you can use this : label with hidden input (icon is present).

Android EditText view Floating Hint in Material Design

@andruboy's suggestion of is probably your best bet. kind of works with appcompat-v7 v21.0.0, but since v21.0.0 does not support accent colors with subclasses of EditText, the underline of the FloatingHintEditText will be the default solid black or white. Also the padding is not optimized for the Material style EditText, so you may need to adjust it.

How can I install packages using pip according to the requirements.txt file from a local directory?

For virtualenv to install all files in the requirements.txt file.

  1. cd to the directory where requirements.txt is located
  2. activate your virtualenv
  3. run: pip install -r requirements.txt in your shell

Auto submit form on page load

Try this On window load submit your form.

window.onload = function(){

How to debug ORA-01775: looping chain of synonyms?

The data dictionary table DBA_SYNONYMS has information about all the synonyms in a database. So you can run the query

SELECT table_owner, table_name, db_link
  FROM dba_synonyms 
 WHERE owner        = 'PUBLIC'
   AND synonym_name = <<synonym name>>

to see what the public synonym currently points at.

Display Records From MySQL Database using JTable in Java

this is the easy way to do that you just need to download the jar file "rs2xml.jar" add it to your project and do that : 1- creat a connection 2- statment and resultset 3- creat a jtable 4- give the result set to DbUtils.resultSetToTableModel(rs) as define in this methode you well get your jtable so easy.

public void afficherAll(String tableName){
        String sql="select * from "+tableName;
        try {
        } catch (SQLException e) {
            // TODO Auto-generated catch block
             JOptionPane.showMessageDialog(null, e);

How to get javax.comm API?

Oracle Java Communications API Reference -

Official 3.0 Download (Solarix, Linux) -

Unofficial 2.0 Download (All):

Unofficial 2.0 Download (Windows installer) -

In order to ensure there is no compilation error, place the file on your classpath when compiling (-cp command-line option, or check your IDE documentation).

What is the usefulness of PUT and DELETE HTTP request methods?

Safe Methods : Get Resource/No modification in resource
Idempotent : No change in resource status if requested many times
Unsafe Methods : Create or Update Resource/Modification in resource
Non-Idempotent : Change in resource status if requested many times

According to your requirement :

1) For safe and idempotent operation (Fetch Resource) use --------- GET METHOD
2) For unsafe and non-idempotent operation (Insert Resource) use--------- POST METHOD
3) For unsafe and idempotent operation (Update Resource) use--------- PUT METHOD
3) For unsafe and idempotent operation (Delete Resource) use--------- DELETE METHOD

How does Content Security Policy (CSP) work?

Apache 2 mod_headers

You could also enable Apache 2 mod_headers. On Fedora it's already enabled by default. If you use Ubuntu/Debian, enable it like this:

# First enable headers module for Apache 2,
# and then restart the Apache2 service
a2enmod headers
apache2 -k graceful

On Ubuntu/Debian you can configure headers in the file /etc/apache2/conf-enabled/security.conf

# Setting this header will prevent MSIE from interpreting files as something
# else than declared by the content type in the HTTP headers.
# Requires mod_headers to be enabled.
#Header set X-Content-Type-Options: "nosniff"

# Setting this header will prevent other sites from embedding pages from this
# site as frames. This defends against clickjacking attacks.
# Requires mod_headers to be enabled.
Header always set X-Frame-Options: "sameorigin"
Header always set X-Content-Type-Options nosniff
Header always set X-XSS-Protection "1; mode=block"
Header always set X-Permitted-Cross-Domain-Policies "master-only"
Header always set Cache-Control "no-cache, no-store, must-revalidate"
Header always set Pragma "no-cache"
Header always set Expires "-1"
Header always set Content-Security-Policy: "default-src 'none';"
Header always set Content-Security-Policy: "script-src 'self';"
Header always set Content-Security-Policy: "style-src 'self';"

Note: This is the bottom part of the file. Only the last three entries are CSP settings.

The first parameter is the directive, the second is the sources to be white-listed. I've added Google analytics and an adserver, which you might have. Furthermore, I found that if you have aliases, e.g, and configured in Apache 2 you should add them to the white-list as well.

Inline code is considered harmful, and you should avoid it. Copy all the JavaScript code and CSS to separate files and add them to the white-list.

While you're at it you could take a look at the other header settings and install mod_security

Further reading:

How do you convert a byte array to a hexadecimal string, and vice versa?

From Microsoft's developers, a nice, simple conversion:

public static string ByteArrayToString(byte[] ba) 
    // Concatenate the bytes into one long string
    return ba.Aggregate(new StringBuilder(32),
                            (sb, b) => sb.Append(b.ToString("X2"))

While the above is clean and compact, performance junkies will scream about it using enumerators. You can get peak performance with an improved version of Tomalak's original answer:

public static string ByteArrayToString(byte[] ba)   
   StringBuilder hex = new StringBuilder(ba.Length * 2);   

   for(int i=0; i < ba.Length; i++)       // <-- Use for loop is faster than foreach   
       hex.Append(ba[i].ToString("X2"));   // <-- ToString is faster than AppendFormat   

   return hex.ToString();   

This is the fastest of all the routines I've seen posted here so far. Don't just take my word for it... performance test each routine and inspect its CIL code for yourself.

Select method of Range class failed via VBA

I believe you are having the same problem here.
The sheet must be active before you can select a range on it.

Also, don't omit the sheet name qualifier:

Sheets("BxWsn Simulation").Select
Sheets("BxWsn Simulation").Range("Result").Select


With Sheets("BxWsn Simulation")
End WIth

which is the same.

Adding Git-Bash to the new Windows Terminal

That's how I've added mine in profiles json table,

    "guid": "{00000000-0000-0000-ba54-000000000002}",
    "name": "Git",
    "commandline": "C:/Program Files/Git/bin/bash.exe --login",
    "icon": "%PROGRAMFILES%/Git/mingw64/share/git/git-for-windows.ico",
    "startingDirectory": "%USERPROFILE%",
    "hidden": false

Convert a SQL query result table to an HTML table for email

Here is one way to do it from an article titled "Format query output into an HTML table - the easy way [archive]". You would need to substitute the details of your own query for the ones in this example, which gets a list of tables and a row count.

declare @body varchar(max)

set @body = cast( (
select td = dbtable + '</td><td>' + cast( entities as varchar(30) ) + '</td><td>' + cast( rows as varchar(30) )
from (
      select dbtable  = object_name( object_id ),
             entities = count( distinct name ),
             rows     = count( * )
      from sys.columns
      group by object_name( object_id )
      ) as d
for xml path( 'tr' ), type ) as varchar(max) )

set @body = '<table cellpadding="2" cellspacing="2" border="1">'
          + '<tr><th>Database Table</th><th>Entity Count</th><th>Total Rows</th></tr>'
          + replace( replace( @body, '&lt;', '<' ), '&gt;', '>' )
          + '</table>'

print @body

Once you have @body, you can then use whatever email mechanism you want.

How to auto-generate a C# class file from a JSON string

Visual Studio 2012 (with ASP.NET and Web Tools 2012.2 RC installed) supports this natively.

Visual Studio 2013 onwards have this built-in.

Visual Studio Paste JSON as Classes screenshot (Image courtesy: robert.muehsig)

What bitrate is used for each of the youtube video qualities (360p - 1080p), in regards to flowplayer?

Looking at this official google link: Youtube Live encoder settings, bitrates and resolutions they have this table:

                   240p       360p        480p        720p        1080p
Resolution      426 x 240   640 x 360   854x480     1280x720    1920x1080
Video Bitrates                   
Maximum         700 Kbps    1000 Kbps   2000 Kbps   4000 Kbps   6000 Kbps
Recommended     400 Kbps    750 Kbps    1000 Kbps   2500 Kbps   4500 Kbps
Minimum         300 Kbps    400 Kbps    500 Kbps    1500 Kbps   3000 Kbps

It would appear as though this is the case, although the numbers dont sync up to the google table above:

// the bitrates, video width and file names for this clip
      bitrates: [
        { url: "bbb-800.mp4", width: 480, bitrate: 800 }, //360p video
        { url: "bbb-1200.mp4", width: 720, bitrate: 1200 }, //480p video
        { url: "bbb-1600.mp4", width: 1080, bitrate: 1600 } //720p video

How to set base url for rest in spring boot?

With spring-boot 2.x you can configure in


Splitting a table cell into two columns in HTML

I came here for a similar problem I was facing with my table headers.

@MrMisterMan's answer, as well as others, were really helpful, but the borders were beating my game. So, I did some research to find the use rowspan.

Here's what I did and I guess it might help others facing something similar.

<table style="width: 100%; margin-top: 10px; font-size: 0.8em;" border="1px">_x000D_
    <tr align="center" >_x000D_
        <th style="padding:2.5px; width: 10%;" rowspan="2">Item No</th>_x000D_
        <th style="padding:2.5px; width: 55%;" rowspan="2">DESCRIPTION</th>_x000D_
        <th style="padding:2.5px;" rowspan="2">Quantity</th>_x000D_
        <th style="padding:2.5px;" colspan="2">Rate per Item</th>_x000D_
        <th style="padding:2.5px;" colspan="2">AMOUNT</th>_x000D_

Extracting specific columns in numpy array

One thing I would like to point out is, if the number of columns you want to extract is 1 the resulting matrix would not be a Mx1 Matrix as you might expect but instead an array containing the elements of the column you extracted.

To convert it to Matrix the reshape(M,1) method should be used on the resulting array.

How to prevent scrollbar from repositioning web page?

I used some jquery to solve this

    'overflow-y': 'hidden'

  $(window).load(function() {
      'overflow-y': ''

export html table to csv

I used Calumah's function posted above, but I did run into an issue with his code as poisted.

The rows are joined with a semicolon


but the link generated has "text/csv" as the content type

Maybe in Windows that isn't a problem, but in Excel for Mac that throws things off. I changed the array join to a comma and it worked perfect.

Check if bash variable equals 0

Double parenthesis (( ... )) is used for arithmetic operations.

Double square brackets [[ ... ]] can be used to compare and examine numbers (only integers are supported), with the following operators:

· NUM1 -eq NUM2 returns true if NUM1 and NUM2 are numerically equal.

· NUM1 -ne NUM2 returns true if NUM1 and NUM2 are not numerically equal.

· NUM1 -gt NUM2 returns true if NUM1 is greater than NUM2.

· NUM1 -ge NUM2 returns true if NUM1 is greater than or equal to NUM2.

· NUM1 -lt NUM2 returns true if NUM1 is less than NUM2.

· NUM1 -le NUM2 returns true if NUM1 is less than or equal to NUM2.

For example

if [[ $age > 21 ]] # bad, > is a string comparison operator

if [ $age > 21 ] # bad, > is a redirection operator

if [[ $age -gt 21 ]] # okay, but fails if $age is not numeric

if (( $age > 21 )) # best, $ on age is optional

What version of MongoDB is installed on Ubuntu

When you entered in mongo shell using "mongo" command , that time only you will notice

MongoDB shell version v3.4.0-rc2
connecting to: mongodb://
MongoDB server version: 3.4.0-rc2

also you can try command,in mongo shell , db.version()

Import SQL file into mysql

Don't forget to use

charset utf8

If your sql file is in utf-8 :)

So you need to do:


mysql -u root

mysql> charset utf8

mysql> use mydbname

mysql> source C:\myfolder\myfile.sql

Good luck ))

What does "select count(1) from table_name" on any database tables mean?

There is no difference.

COUNT(1) is basically just counting a constant value 1 column for each row. As other users here have said, it's the same as COUNT(0) or COUNT(42). Any non-NULL value will suffice.

The Oracle optimizer did apparently use to have bugs in it, which caused the count to be affected by which column you picked and whether it was in an index, so the COUNT(1) convention came into being.

Install php-mcrypt on CentOS 6

For me I had to add the EPEL repository. It is where my php-mcrypt came from:

[root@system ~]$ repoquery -i php-mcrypt

Name        : php-mcrypt
Version     : 5.3.3
Release     : 1.el6
Architecture: i686
Size        : 39225
Packager    : Fedora Project
Group       : Development/Languages
URL         :
Repository  : epel <----------
Summary     : Standard PHP module provides mcrypt library support
Source      : php-extras-5.3.3-1.el6.src.rpm
Description :
Standard PHP module provides mcrypt library support

You can enable the EPEL repo with the instructions here:

Check if two unordered lists are equal

Python has a built-in datatype for an unordered collection of (hashable) things, called a set. If you convert both lists to sets, the comparison will be unordered.

set(x) == set(y)

Documentation on set

EDIT: @mdwhatcott points out that you want to check for duplicates. set ignores these, so you need a similar data structure that also keeps track of the number of items in each list. This is called a multiset; the best approximation in the standard library is a collections.Counter:

>>> import collections
>>> compare = lambda x, y: collections.Counter(x) == collections.Counter(y)
>>> compare([1,2,3], [1,2,3,3])
>>> compare([1,2,3], [1,2,3])
>>> compare([1,2,3,3], [1,2,2,3])

push object into array

can be done like this too.

       let data_array = [];
       let my_object = {}; = "stack";
       my_object.age = 20;
       my_object.hair_color = "red";
       my_object.eye_color = "green";

Git push failed, "Non-fast forward updates were rejected"

I encountered the same error, just add "--force" to the command, it works

git push origin master --force

How to handle authentication popup with Selenium WebDriver using Java

Don't use firefox profile and try below code:

driver.get("http://UserName:[email protected]");

If you're implementing it in IE browser, there are certain things which you need to do.

In case your authentication server requires username with domain like "domainuser" you need to add double slash / to the url:

//localdomain\user:[email protected]

How do I use raw_input in Python 3

Timmerman's solution works great when running the code, but if you don't want to get Undefined name errors when using pyflakes or a similar linter you could use the following instead:

    import __builtin__
    input = getattr(__builtin__, 'raw_input')
except (ImportError, AttributeError):

Get rid of "The value for annotation attribute must be a constant expression" message

The value for an annotation must be a compile time constant, so there is no simple way of doing what you are trying to do.

See also here: How to supply value to an annotation from a Constant java

It is possible to use some compile time tools (ant, maven?) to config it if the value is known before you try to run the program.

Edit a specific Line of a Text File in C#

You can't rewrite a line without rewriting the entire file (unless the lines happen to be the same length). If your files are small then reading the entire target file into memory and then writing it out again might make sense. You can do that like this:

using System;
using System.IO;

class Program
    static void Main(string[] args)
        int line_to_edit = 2; // Warning: 1-based indexing!
        string sourceFile = "source.txt";
        string destinationFile = "target.txt";

        // Read the appropriate line from the file.
        string lineToWrite = null;
        using (StreamReader reader = new StreamReader(sourceFile))
            for (int i = 1; i <= line_to_edit; ++i)
                lineToWrite = reader.ReadLine();

        if (lineToWrite == null)
            throw new InvalidDataException("Line does not exist in " + sourceFile);

        // Read the old file.
        string[] lines = File.ReadAllLines(destinationFile);

        // Write the new file over the old file.
        using (StreamWriter writer = new StreamWriter(destinationFile))
            for (int currentLine = 1; currentLine <= lines.Length; ++currentLine)
                if (currentLine == line_to_edit)
                    writer.WriteLine(lines[currentLine - 1]);

If your files are large it would be better to create a new file so that you can read streaming from one file while you write to the other. This means that you don't need to have the whole file in memory at once. You can do that like this:

using System;
using System.IO;

class Program
    static void Main(string[] args)
        int line_to_edit = 2;
        string sourceFile = "source.txt";
        string destinationFile = "target.txt";
        string tempFile = "target2.txt";

        // Read the appropriate line from the file.
        string lineToWrite = null;
        using (StreamReader reader = new StreamReader(sourceFile))
            for (int i = 1; i <= line_to_edit; ++i)
                lineToWrite = reader.ReadLine();

        if (lineToWrite == null)
            throw new InvalidDataException("Line does not exist in " + sourceFile);

        // Read from the target file and write to a new file.
        int line_number = 1;
        string line = null;
        using (StreamReader reader = new StreamReader(destinationFile))
        using (StreamWriter writer = new StreamWriter(tempFile))
            while ((line = reader.ReadLine()) != null)
                if (line_number == line_to_edit)

        // TODO: Delete the old file and replace it with the new file here.

You can afterwards move the file once you are sure that the write operation has succeeded (no excecption was thrown and the writer is closed).

Note that in both cases it is a bit confusing that you are using 1-based indexing for your line numbers. It might make more sense in your code to use 0-based indexing. You can have 1-based index in your user interface to your program if you wish, but convert it to a 0-indexed before sending it further.

Also, a disadvantage of directly overwriting the old file with the new file is that if it fails halfway through then you might permanently lose whatever data wasn't written. By writing to a third file first you only delete the original data after you are sure that you have another (corrected) copy of it, so you can recover the data if the computer crashes halfway through.

A final remark: I noticed that your files had an xml extension. You might want to consider if it makes more sense for you to use an XML parser to modify the contents of the files instead of replacing specific lines.

Recommended add-ons/plugins for Microsoft Visual Studio

+1 Visual Assist.

It's unfortunate that you need a plugin to get really good intellisense but it's definitely worth paying for.

Pip install Matplotlib error with virtualenv

To generate graph in png format you need to Install following dependent packages

sudo apt-get install libpng-dev
sudo apt-get install libfreetype6-dev

Ubuntu or using following command

sudo apt-get install libpng12-0

Using GPU from a docker container?

Ok i finally managed to do it without using the --privileged mode.

I'm running on ubuntu server 14.04 and i'm using the latest cuda (6.0.37 for linux 13.04 64 bits).


Install nvidia driver and cuda on your host. (it can be a little tricky so i will suggest you follow this guide

ATTENTION : It's really important that you keep the files you used for the host cuda installation

Get the Docker Daemon to run using lxc

We need to run docker daemon using lxc driver to be able to modify the configuration and give the container access to the device.

One time utilization :

sudo service docker stop
sudo docker -d -e lxc

Permanent configuration Modify your docker configuration file located in /etc/default/docker Change the line DOCKER_OPTS by adding '-e lxc' Here is my line after modification

DOCKER_OPTS="--dns --dns -e lxc"

Then restart the daemon using

sudo service docker restart

How to check if the daemon effectively use lxc driver ?

docker info

The Execution Driver line should look like that :

Execution Driver: lxc-1.0.5

Build your image with the NVIDIA and CUDA driver.

Here is a basic Dockerfile to build a CUDA compatible image.

FROM ubuntu:14.04

RUN apt-get update && apt-get install -y build-essential
RUN apt-get --purge remove -y nvidia*

ADD ./Downloads/nvidia_installers /tmp/nvidia                             > Get the install files you used to install CUDA and the NVIDIA drivers on your host
RUN /tmp/nvidia/ -s -N --no-kernel-module   > Install the driver.
RUN rm -rf /tmp/selfgz7                                                   > For some reason the driver installer left temp files when used during a docker build (i don't have any explanation why) and the CUDA installer will fail if there still there so we delete them.
RUN /tmp/nvidia/ -noprompt            > CUDA driver installer.
RUN /tmp/nvidia/ -noprompt -cudaprefix=/usr/local/cuda-6.0   > CUDA samples comment if you don't want them.
RUN export LD_LIBRARY_PATH=$LD_LIBRARY_PATH:/usr/local/cuda/lib64         > Add CUDA library into your PATH
RUN touch /etc/                                     > Update the directory
RUN rm -rf /temp/*  > Delete installer files.

Run your image.

First you need to identify your the major number associated with your device. Easiest way is to do the following command :

ls -la /dev | grep nvidia

If the result is blank, use launching one of the samples on the host should do the trick. The result should look like that enter image description here As you can see there is a set of 2 numbers between the group and the date. These 2 numbers are called major and minor numbers (wrote in that order) and design a device. We will just use the major numbers for convenience.

Why do we activated lxc driver? To use the lxc conf option that allow us to permit our container to access those devices. The option is : (i recommend using * for the minor number cause it reduce the length of the run command)

--lxc-conf='lxc.cgroup.devices.allow = c [major number]:[minor number or *] rwm'

So if i want to launch a container (Supposing your image name is cuda).

docker run -ti --lxc-conf='lxc.cgroup.devices.allow = c 195:* rwm' --lxc-conf='lxc.cgroup.devices.allow = c 243:* rwm' cuda

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

Both UTF8 and UTF-8 work for me.

How to fill OpenCV image with one solid color?

Using the OpenCV C API with IplImage* img:

Use cvSet(): cvSet(img, CV_RGB(redVal,greenVal,blueVal));

Using the OpenCV C++ API with cv::Mat img, then use either:

cv::Mat::operator=(const Scalar& s) as in:

img = cv::Scalar(redVal,greenVal,blueVal);

or the more general, mask supporting, cv::Mat::setTo():


How to mock static methods in c# using MOQ framework?

Another option to transform the static method into a static Func or Action. For instance.

Original code:

    class Math
        public static int Add(int x, int y)
            return x + y;

You want to "mock" the Add method, but you can't. Change the above code to this:

        public static Func<int, int, int> Add = (x, y) =>
            return x + y;

Existing client code doesn't have to change (maybe recompile), but source stays the same.

Now, from the unit-test, to change the behavior of the method, just reassign an in-line function to it:

    public static void MyTest()
        Math.Add = (x, y) =>
            return 11;

Put whatever logic you want in the method, or just return some hard-coded value, depending on what you're trying to do.

This may not necessarily be something you can do each time, but in practice, I found this technique works just fine.

[edit] I suggest that you add the following Cleanup code to your Unit Test class:

    public void Cleanup()
        typeof(Math).TypeInitializer.Invoke(null, null);

Add a separate line for each static class. What this does is, after the unit test is done running, it resets all the static fields back to their original value. That way other unit tests in the same project will start out with the correct defaults as opposed your mocked version.

Can't push to remote branch, cannot be resolved to branch

For me, the issue was I had git and my macOS filesystem set to two different case sensitivities. My Mac was formatted APFS/Is Case-Sensitive: NO but I had flipped my git settings at some point trying to get over a weird issue with Xcode image asset naming so git config --global core.ignorecase false. By flipping it back aligned the settings and recreating the branch and pushing got me back on track.

git config --global core.ignorecase true


HTML5 Video autoplay on iPhone

Does playsinline attribute help?

Here's what I have:

<video autoplay loop muted playsinline class="video-background ">
  <source src="videos/intro-video3.mp4" type="video/mp4">

See the comment on playsinline here:

What is an .inc and why use it?

If you are concerned about the file's content being served rather than its output. You can use a double extension like: It then serves the same purpose of helpfulness and maintainability.

I normally have 2 php files for each page on my site:

  1. One named welcome.php in the root folder, containing all of the HTML markup.
  2. And another named in the inc folder, containing all PHP functions specific to the welcome.php page.

EDIT: Another benefit of using the double extention .inc.php would be that any IDE can still recognise the file as PHP code.

how to print a string to console in c++

All you have to do is add:

#include <string>
using namespace std;

at the top. (BTW I know this was posted in 2013 but I just wanted to answer)

How to create a md5 hash of a string in C?

All of the existing answers use the deprecated MD5Init(), MD5Update(), and MD5Final().

Instead, use EVP_DigestInit_ex(), EVP_DigestUpdate(), and EVP_DigestFinal_ex(), e.g.

// example.c
// gcc example.c -lssl -lcrypto -o example

#include <openssl/evp.h>
#include <stdio.h>
#include <string.h>

void bytes2md5(const char *data, int len, char *md5buf) {
  // Based on
  EVP_MD_CTX *mdctx = EVP_MD_CTX_new();
  const EVP_MD *md = EVP_md5();
  unsigned char md_value[EVP_MAX_MD_SIZE];
  unsigned int md_len, i;
  EVP_DigestInit_ex(mdctx, md, NULL);
  EVP_DigestUpdate(mdctx, data, len);
  EVP_DigestFinal_ex(mdctx, md_value, &md_len);
  for (i = 0; i < md_len; i++) {
    snprintf(&(md5buf[i * 2]), 16 * 2, "%02x", md_value[i]);

int main(void) {
  const char *hello = "hello";
  char md5[33]; // 32 characters + null terminator
  bytes2md5(hello, strlen(hello), md5);
  printf("%s\n", md5);

How to use environment variables in docker compose

Since 1.25.4, docker-compose supports the option --env-file that enables you to specify a file containing variables.

Yours should look like this:


And the command:

docker-compose --env-file /path/to/my-env-file config

Jenkins/Hudson - accessing the current build number?

I've just come across this question too and found out that if anytime the build number gets corrupt because of any error-triggered hard shutdown of the jenkins instance you can set back the build number manually by just editing the file nextBuildNumber (pathToJenkins\jobs\jobxyz\nextBuildNumber) and then make a reload by using the option
Reload Configuration from Disk from the Manage Jenkins View.

How can you encode a string to Base64 in JavaScript?

There's a couple of bugs in both implementations of _utf8_decode. c1 and c2 are assigned as global variables due to broken use of the var statement, and c3 is not initialized or declared at all.

It works, but these variables will overwrite any existing ones with the same name outside this function.

Here's a version that won't do this:

// private method for UTF-8 decoding
_utf8_decode : function (utftext) {
    var string = "";
    var i = 0;
    var c = 0, c1 = 0, c2 = 0;

    while ( i < utftext.length ) {

        c = utftext.charCodeAt(i);

        if (c < 128) {
            string += String.fromCharCode(c);
        else if((c > 191) && (c < 224)) {
            c1 = utftext.charCodeAt(i+1);
            string += String.fromCharCode(((c & 31) << 6) | (c1 & 63));
            i += 2;
        else {
            c1 = utftext.charCodeAt(i+1);
            c2 = utftext.charCodeAt(i+2);
            string += String.fromCharCode(((c & 15) << 12) | ((c1 & 63) << 6) | (c2 & 63));
            i += 3;

    return string;

Use string value from a cell to access worksheet of same name

You need INDIRECT function:


How to implement the factory method pattern in C++ correctly

extern std::pair<std::string_view, Base*(*)()> const factories[2];

decltype(factories) factories{
  {"blah", []() -> Base*{return new Blah;}},
  {"foo", []() -> Base*{return new Foo;}}

How to use OR condition in a JavaScript IF statement?

If we're going to mention regular expressions, we might as well mention the switch statement.

var expr = 'Papayas';_x000D_
switch (expr) {_x000D_
  case 'Oranges':_x000D_
    console.log('Oranges are $0.59 a pound.');_x000D_
  case 'Mangoes':_x000D_
  case 'Papayas': // Mangoes or papayas_x000D_
    console.log('Mangoes and papayas are $2.79 a pound.');_x000D_
    // expected output: "Mangoes and papayas are $2.79 a pound."_x000D_
    console.log('Sorry, we are out of ' + expr + '.');_x000D_

This version of Android Studio cannot open this project, please retry with Android Studio 3.4 or newer

i just change gradle version classpath '' to classpath '' and now working.

How do I fix the indentation of an entire file in Vi?

:set paste is your friend I use putty and end up copying code between windows. Before I was turned on to :set paste (and :set nopaste) copy/paste gave me fits for that very reason.

Why does using an Underscore character in a LIKE filter give me all the results?

The underscore is the wildcard in a LIKE query for one arbitrary character.

Hence LIKE %_% means "give me all records with at least one arbitrary character in this column".

You have to escape the wildcard character, in sql-server with [] around:

FROM Manager m 
WHERE m.managerid    LIKE  '[_]%'
AND   m.managername  LIKE '%[_]%'

See: LIKE (Transact-SQL)


Using R to download zipped data file, extract, and import data

Zip archives are actually more a 'filesystem' with content metadata etc. See help(unzip) for details. So to do what you sketch out above you need to

  1. Create a temp. file name (eg tempfile())
  2. Use download.file() to fetch the file into the temp. file
  3. Use unz() to extract the target file from temp. file
  4. Remove the temp file via unlink()

which in code (thanks for basic example, but this is simpler) looks like

temp <- tempfile()
data <- read.table(unz(temp, "a1.dat"))

Compressed (.z) or gzipped (.gz) or bzip2ed (.bz2) files are just the file and those you can read directly from a connection. So get the data provider to use that instead :)

What's the difference between dependencies, devDependencies and peerDependencies in npm package.json file?

As an example, mocha would normally be a devDependency, since testing isn't necessary in production, while express would be a dependency.

Specify an SSH key for git push for a given domain

Another alternative is to use ssh-ident, to manage your ssh identities.

It automatically loads and uses different keys based on your current working directory, ssh options, and so on... which means you can easily have a work/ directory and private/ directory that transparently end up using different keys and identities with ssh.

AddTransient, AddScoped and AddSingleton Services Differences


AddSingleton() creates a single instance of the service when it is first requested and reuses that same instance in all the places where that service is needed.


In a scoped service, with every HTTP request, we get a new instance. However, within the same HTTP request, if the service is required in multiple places, like in the view and in the controller, then the same instance is provided for the entire scope of that HTTP request. But every new HTTP request will get a new instance of the service.


With a transient service, a new instance is provided every time a service instance is requested whether it is in the scope of the same HTTP request or across different HTTP requests.

What does an exclamation mark mean in the Swift language?

If john were an optional var (declared thusly)

var john: Person?

then it would be possible for john to have no value (in ObjC parlance, nil value)

The exclamation point basically tells the compiler "I know this has a value, you don't need to test for it". If you didn't want to use it, you could conditionally test for it:

if let otherPerson = john {
    otherPerson.apartment = number73

The interior of this will only evaluate if john has a value.

Fastest way to copy a file in Node.js

For fast copies you should use the fs.constants.COPYFILE_FICLONE flag. It allows (for filesystems that support this) to not actually copy the content of the file. Just a new file entry is created, but it points to a Copy-on-Write "clone" of the source file.

To do nothing/less is the fastest way of doing something ;)

let fs = require("fs");

  (err) => {
    if (err) {
      // TODO: handle error

Using promises instead:

let fs = require("fs");
let util = require("util");
let copyFile = util.promisify(fs.copyFile);

  .catch(() => console.log("error"))
  .then(() => console.log("success"));

How to make nginx to listen to server_name:port

The server_namedocs directive is used to identify virtual hosts, they're not used to set the binding.

netstat tells you that nginx listens on which means that it will accept connections from any IP.

If you want to change the IP nginx binds on, you have to change the listendocs rule.
So, if you want to set nginx to bind to localhost, you'd change that to:


In this way, requests that are not coming from localhost are discarded (they don't even hit nginx).

How to view kafka message

You can try Kafka Magic - it's free and you can write complex queries in JavaScript referencing message properties and metadata. Works with Avro serialization too

GCC: array type has incomplete element type

The compiler needs to know the size of the second dimension in your two dimensional array. For example:

void print_graph(g_node graph_node[], double weight[][5], int nodes);

How do I give text or an image a transparent background using CSS?

Either use a semi-transparent PNG image or use CSS 3:

background-color: rgba(255, 0, 0, 0.5);

Here's an article from, Opacity, RGBA and compromise (2007-06-03).

<p style="background-color: rgba(255, 0, 0, 0.5);">_x000D_
  <span>Hello, World!</span>_x000D_

How to create an Array, ArrayList, Stack and Queue in Java?

Just a small correction to the first answer in this thread.

Even for Stack, you need to create new object with generics if you are using Stack from java util packages.

Right usage:
    Stack<Integer> s = new Stack<Integer>();
    Stack<String> s1 = new Stack<String>();



if used otherwise, as mentioned in above post, which is:

    Stack myStack = new Stack();
    // add any type of elements (String, int, etc..)

Although this code works fine, has unsafe or unchecked operations which results in error.

binning data in python with scipy/numpy

I would add, and also to answer the question find mean bin values using histogram2d python that the scipy also have a function specially designed to compute a bidimensional binned statistic for one or more sets of data

import numpy as np
from scipy.stats import binned_statistic_2d

x = np.random.rand(100)
y = np.random.rand(100)
values = np.random.rand(100)
bin_means = binned_statistic_2d(x, y, values, bins=10).statistic

the function scipy.stats.binned_statistic_dd is a generalization of this funcion for higher dimensions datasets

Keep the order of the JSON keys during JSON conversion to CSV

Tested the wink solution, and working fine:

public void testJSONObject() {
    JSONObject jsonObject = new JSONObject();
    jsonObject.put("bbb", "xxx");
    jsonObject.put("ccc", "xxx");
    jsonObject.put("aaa", "xxx");
    jsonObject.put("xxx", "xxx");

public void testWinkJSONObject() throws JSONException {
    org.apache.wink.json4j.JSONObject jsonObject = new OrderedJSONObject();
    jsonObject.put("bbb", "xxx");
    jsonObject.put("ccc", "xxx");
    jsonObject.put("aaa", "xxx");
    jsonObject.put("xxx", "xxx");
    assertEquals("{\"bbb\":\"xxx\",\"ccc\":\"xxx\",\"aaa\":\"xxx\",\"xxx\":\"xxx\"}", jsonObject.toString());

Disabling same-origin policy in Safari

If you want to disable the same-origin policy on Safari (I have 9.1.1), then you only need to enable the developer menu, and select "Disable Cross-Origin Restrictions" from the develop menu.

CSS horizontal centering of a fixed div?

Edit September 2016: Although it's nice to still get an occasional up-vote for this, because the world has moved on, I'd now go with the answer that uses transform (and which has a ton of upvotes). I wouldn't do it this way any more.

Another way not to have to calculate a margin or need a sub-container:

#menu {
    position: fixed;   /* Take it out of the flow of the document */
    left: 0;           /* Left edge at left for now */
    right: 0;          /* Right edge at right for now, so full width */ 
    top: 30px;         /* Move it down from top of window */
    width: 500px;      /* Give it the desired width */ 
    margin: auto;      /* Center it */
    max-width: 100%;   /* Make it fit window if under 500px */ 
    z-index: 10000;    /* Whatever needed to force to front (1 might do) */

How do I vertically align text in a div?

Using flex, be careful with differences in browsers' rendering.

This works well both for Chrome and Internet Explorer:

.outer {_x000D_
    display: flex;_x000D_
    width: 200px;_x000D_
    height: 200px;_x000D_
    background-color: #ffc;_x000D_
.inner {_x000D_
    display: flex;_x000D_
    width: 50%;_x000D_
    height: 50%;_x000D_
    margin: auto;_x000D_
    text-align: center;_x000D_
    justify-content: center;_x000D_
    align-items: center;_x000D_
    background-color: #fcc;_x000D_
<div class="outer"><div class="inner">Active Tasks</div></div>

Compare with this one that works only with Chrome:

.outer {_x000D_
    display: flex;_x000D_
    width: 200px;_x000D_
    height: 200px;_x000D_
    background-color: #ffc;_x000D_
.inner {_x000D_
    display: flex;_x000D_
    width: 50%;_x000D_
    height: 50%;_x000D_
    margin: auto;_x000D_
    background-color: #fcc;_x000D_
<div class="outer">_x000D_
<div class="inner"><span style=" margin: auto;">Active Tasks</span></div>_x000D_

Get the content of a sharepoint folder with Excel VBA

In addition to:

myFilePath = replace(myFilePath, "/", "\")
myFilePath = replace(myFilePath, "http:", "")

also replace space:

myFilePath = replace(myFilePath, " ", "%20")

How to resolve symbolic links in a shell script

Is your path a directory, or might it be a file? If it's a directory, it's simple:

(cd "$DIR"; pwd -P)

However, if it might be a file, then this won't work:

DIR=$(cd $(dirname "$FILE"); pwd -P); echo "${DIR}/$(readlink "$FILE")"

because the symlink might resolve into a relative or full path.

On scripts I need to find the real path, so that I might reference configuration or other scripts installed together with it, I use this:

while [ -h "$SOURCE" ]; do # resolve $SOURCE until the file is no longer a symlink
  DIR="$( cd -P "$( dirname "$SOURCE" )" && pwd )"
  SOURCE="$(readlink "$SOURCE")"
  [[ $SOURCE != /* ]] && SOURCE="$DIR/$SOURCE" # if $SOURCE was a relative symlink, we need to resolve it relative to the path where the symlink file was located

You could set SOURCE to any file path. Basically, for as long as the path is a symlink, it resolves that symlink. The trick is in the last line of the loop. If the resolved symlink is absolute, it will use that as SOURCE. However, if it is relative, it will prepend the DIR for it, which was resolved into a real location by the simple trick I first described.

Selecting a Linux I/O Scheduler

The Linux Kernel does not automatically change the IO Scheduler at run-time. By this I mean, the Linux kernel, as of today, is not able to automatically choose an "optimal" scheduler depending on the type of secondary storage devise. During start-up, or during run-time, it is possible to change the IO scheduler manually.

The default scheduler is chosen at start-up based on the contents in the file located at /linux-2.6 /block/Kconfig.iosched. However, it is possible to change the IO scheduler during run-time by echoing a valid scheduler name into the file located at /sys/block/[DEV]/queue/scheduler. For example, echo deadline > /sys/block/hda/queue/scheduler

How can I make space between two buttons in same div?

you should use bootstrap v.4

<div class="form-group row">
    <div class="col-md-6">
        <input type="button" class="btn form-control" id="btn1">
    <div class="col-md-6">
        <input type="button" class="btn form-control" id="btn2">

How to break out from a ruby block?

next and break seem to do the correct thing in this simplified example!

class Bar
  def self.do_things
      Foo.some_method(1..10) do |x|
            next if x == 2
            break if x == 9
            print "#{x} "

class Foo
    def self.some_method(targets, &block)
      targets.each do |target|
          r = yield(target)
        rescue  => x
          puts "rescue #{x}"


output: 1 3 4 5 6 7 8

Terminating a Java Program

  • Well, first System.exit(0) is used to terminate the program and having statements below it is not correct, although the compiler does not throw any errors.
  • a plain return; is used in a method of void return type to return the control of execution to its parent method.

How do you make an element "flash" in jQuery

This function makes it blink. It must use cssHooks, because of the rgb default return of background-color function.

Hope it helps!

$.cssHooks.backgroundColor = {
get: function(elem) {
    if (elem.currentStyle)
        var bg = elem.currentStyle["backgroundColor"];
    else if (window.getComputedStyle)
        var bg = document.defaultView.getComputedStyle(elem,
    if ("rgb") == -1)
        return bg;
    else {
        bg = bg.match(/^rgb\((\d+),\s*(\d+),\s*(\d+)\)$/);
        function hex(x) {
            return ("0" + parseInt(x).toString(16)).slice(-2);
        return "#" + hex(bg[1]) + hex(bg[2]) + hex(bg[3]);
function blink(element,blinkTimes,color,originalColor){
    var changeToColor;
    if(blinkTimes === null || blinkTimes === undefined)
        blinkTimes = 1;
    if(!originalColor || originalColor === null || originalColor === undefined)
        originalColor = $(element).css("backgroundColor");
    if(!color || color === null || color === undefined)
        color = "#ffffdf";
    if($(element).css("backgroundColor") == color){
        changeToColor = originalColor;
        changeToColor = color;
    if(blinkTimes >= 0){
            "background-color": changeToColor,
        }, {
            duration: 500,
            complete: function() {
                blink(element, blinkTimes, color, originalColor);
                return true;
    return true;

Xcode Debugger: view value of variable

Check this How to view contents of NSDictionary variable in Xcode debugger?

I also use

po variableName
print variableName

in Console.

In your case it is possible to execute

print [myData objectAtIndex:indexPath.row]  


po [myData objectAtIndex:indexPath.row]

.Net HttpWebRequest.GetResponse() raises exception when http status code 400 (bad request) is returned

Try this (it's VB-Code :-):


Catch exp As WebException
  Dim sResponse As String = New StreamReader(exp.Response.GetResponseStream()).ReadToEnd
End Try

'uint32_t' identifier not found error

I have the same error and it fixed it including in the file the following

#include <stdint.h>

at the beginning of your file.

urlencode vs rawurlencode?

Spaces encoded as %20 vs. +

The biggest reason I've seen to use rawurlencode() in most cases is because urlencode encodes text spaces as + (plus signs) where rawurlencode encodes them as the commonly-seen %20:

echo urlencode("red shirt");
// red+shirt

echo rawurlencode("red shirt");
// red%20shirt

I have specifically seen certain API endpoints that accept encoded text queries expect to see %20 for a space and as a result, fail if a plus sign is used instead. Obviously this is going to differ between API implementations and your mileage may vary.

Excel VBA Loop on columns

If you want to stick with the same sort of loop then this will work:

Option Explicit

Sub selectColumns()

Dim topSelection As Integer
Dim endSelection As Integer
topSelection = 2
endSelection = 10

Dim columnSelected As Integer
columnSelected = 1
   With Excel.ThisWorkbook.ActiveSheet
        .Range(.Cells(columnSelected, columnSelected), .Cells(endSelection, columnSelected)).Select
   End With
   columnSelected = columnSelected + 1
Loop Until columnSelected > 10

End Sub


If in reality you just want to loop through every cell in an area of the spreadsheet then use something like this:

Sub loopThroughCells()

'this is the starting point
Dim rwMin As Integer
Dim colMin As Integer
rwMin = 2
colMin = 2

'this is the ending point
Dim rwMax As Integer
Dim colMax As Integer
rwMax = 10
colMax = 5

Dim rwIndex As Integer
Dim colIndex As Integer

For rwIndex = rwMin To rwMax
        For colIndex = colMin To colMax
            Cells(rwIndex, colIndex).Select
        Next colIndex
Next rwIndex

End Sub

How to add a ListView to a Column in Flutter?

As have been mentioned by others above,Wrap listview with Expanded is the solution.

But when you deal with nested Columns you will also need to limit your ListView to a certain height (faced this problem a lot).

If anyone have another solution please, mention in comment or add answer.


   child: Column(
     children: <Widget>[
       Image(image: ),//<< any widgets added
         children: <Widget>[
           Text('header'),  //<< any widgets added
              //here your code
               scrollDirection: Axis.horizontal,
        itemCount: items.length,
        itemBuilder: (BuildContext context, int index) {
            return Container();
        Divider(),//<< any widgets added


Detect viewport orientation, if orientation is Portrait display alert message advising user of instructions

After some experimentation I have found that rotating an orientation aware device will always trigger a browser window's resize event. So in your resize handler simply call a function like:

function is_landscape() {
  return (window.innerWidth > window.innerHeight);

Target WSGI script cannot be loaded as Python module

In my own case on windows in xampp, I was incorrectly loading the application path in the file like so:


import sys

os.environ.setdefault("DJANGO_SETTINGS_MODULE", "advisory_portal.settings")

application = get_wsgi_application()

Instead of:


import sys

os.environ.setdefault("DJANGO_SETTINGS_MODULE", "advisory_portal.settings")

application = get_wsgi_application()

Don't forget to import sys python package

How to set dropdown arrow in spinner?

From the API level 16 and above, you can use following code to change the drop down icon in spinner. just goto onItemSelected in setonItemSelectedListener and change the drawable of textview selected like this.

spinner.setOnItemSelectedListener(new AdapterView.OnItemSelectedListener() {
        public void onItemSelected(AdapterView<?> parent, View view, int position, long id) {
  // give the color which ever you want to give to spinner item in this line of code               
//API Level 16 and above only. 
 //Basically itis changing the drawable of textview, we have change the textview left drawable.

        public void onNothingSelected(AdapterView<?> parent) {


hope it will help somebody.

How to delete all files older than 3 days when "Argument list too long"?

Another solution for the original question, esp. useful if you want to remove only SOME of the older files in a folder, would be smth like this:

find . -name "*.sess" -mtime +100 

and so on.. Quotes block shell wildcards, thus allowing you to "find" millions of files :)

How to split string and push in array using jquery

You don't need jQuery for that, you can do it with normal javascript:

var str = "a,b,c,d";
var res = str.split(","); // this returns an array

how to refresh Select2 dropdown menu after ajax loading different content?

Finally solved issue of reinitialization of select2 after ajax call.

You can call this in success function of ajax.

Note : Don't forget to replace ".selector" to your class of <select class="selector"> element.


   placeholder: "Placeholder text",
   allowClear: true


How can I get the CheckBoxList selected values, what I have doesn't seem to work C#.NET/VisualWebPart

// Page.aspx //

// To count checklist item

  int a = ChkMonth.Items.Count;
        int count = 0;

        for (var i = 0; i < a; i++)
            if (ChkMonth.Items[i].Selected == true)

// Page.aspx.cs //

  // To access checkbox list item's value //
   string YrStrList = "";
        foreach (ListItem listItem in ChkMonth.Items)
            if (listItem.Selected)
                YrStrList = YrStrList + "'" + listItem.Value + "'" + ",";


        sMonthStr = YrStrList.ToString();

Extract a substring from a string in Ruby using a regular expression

Here's a slightly more flexible approach using the match method. With this, you can extract more than one string:

s = "<ants> <pants>"
matchdata = s.match(/<([^>]*)> <([^>]*)>/)

# Use 'captures' to get an array of the captures
matchdata.captures   # ["ants","pants"]

# Or use raw indices
matchdata[0]   # whole regex match: "<ants> <pants>"
matchdata[1]   # first capture: "ants"
matchdata[2]   # second capture: "pants"

ant warning: "'includeantruntime' was not set"

Ant Runtime

Simply set includeantruntime="false":

<javac includeantruntime="false" ...>...</javac>

If you have to use the javac-task multiple times you might want to consider using PreSetDef to define your own javac-task that always sets includeantruntime="false".

Additional Details


That's caused by a misfeature introduced in Ant 1.8. Just add an attribute of that name to the javac task, set it to false, and forget it ever happened.


Whether to include the Ant run-time libraries in the classpath; defaults to yes, unless build.sysclasspath is set. It is usually best to set this to false so the script's behavior is not sensitive to the environment in which it is run.

Turning off eslint rule for a specific line

To disable a single rule for the rest of the file below:

/* eslint no-undef: "off"*/
const uploadData = new FormData();

Java: Static Class?

There's no point in declaring the class as static. Just declare its methods static and call them from the class name as normal, like Java's Math class.

Also, even though it isn't strictly necessary to make the constructor private, it is a good idea to do so. Marking the constructor private prevents other people from creating instances of your class, then calling static methods from those instances. (These calls work exactly the same in Java, they're just misleading and hurt the readability of your code.)

$("#form1").validate is not a function

youll need to use the latest in conjunction with one of the Microsoft's CDN for getting your validation file.

How to set the component size with GridLayout? Is there a better way?

An alternative to other layouts, might be to put your panel with the GridLayout, inside another panel that is a FlowLayout. That way your spacing will be intact but will not expand across the entire available space.

Is it possible to run CUDA on AMD GPUs?

As of 2019_10_10 I have NOT tested it, but there is the "GPU Ocelot" project

that according to its advertisement tries to compile CUDA code for a variety of targets, including AMD GPUs.

Link to the issue number on GitHub within a commit message

You can also cross reference repos:


xxx being the issue number

Array vs ArrayList in performance

It is pretty obvious that array[10] is faster than array.get(10), as the later internally does the same call, but adds the overhead for the function call plus additional checks.

Modern JITs however will optimize this to a degree, that you rarely have to worry about this, unless you have a very performance critical application and this has been measured to be your bottleneck.

Setting POST variable without using form

Yes, simply set it to another value:

$_POST['text'] = 'another value';

This will override the previous value corresponding to text key of the array. The $_POST is superglobal associative array and you can change the values like a normal PHP array.

Caution: This change is only visible within the same PHP execution scope. Once the execution is complete and the page has loaded, the $_POST array is cleared. A new form submission will generate a new $_POST array.

If you want to persist the value across form submissions, you will need to put it in the form as an input tag's value attribute or retrieve it from a data store.

Twitter Bootstrap add active class to li

We managed to fix in the end:

/*menu handler*/
  function stripTrailingSlash(str) {
    if(str.substr(-1) == '/') {
      return str.substr(0, str.length - 1);
    return str;

  var url = window.location.pathname;  
  var activePage = stripTrailingSlash(url);

  $('.nav li a').each(function(){  
    var currentPage = stripTrailingSlash($(this).attr('href'));

    if (activePage == currentPage) {

connect to host localhost port 22: Connection refused

Do you have sshd installed? You can verify that with:

which ssh
which sshd

For detailed information you can visit this link.

No Entity Framework provider found for the ADO.NET provider with invariant name 'System.Data.SqlClient'

Also, make sure you startup project is the project that contains your dbcontext (or relevant app.config). Mine was trying to start up a website project which didnt have all the necessary configuration settings.

How to trim whitespace from a Bash variable?

Python has a function strip() that works identically to PHP's trim(), so we can just do a little inline Python to make an easily understandable utility for this:

alias trim='python -c "import sys; sys.stdout.write("'

This will trim leading and trailing whitespace (including newlines).

$ x=`echo -e "\n\t   \n" | trim`
$ if [ -z "$x" ]; then echo hi; fi

$(document).ready shorthand

The shorthand is:

$(function() {
    // Code here

Configure hibernate to connect to database via JNDI Datasource

Tomcat-7 JNDI configuration:


  1. Open the server.xml in the tomcat-dir/conf
  2. Add below <Resource> tag with your DB details inside <GlobalNamingResources>
<Resource name="jdbc/mydb"
  1. Save the server.xml file
  2. Open the context.xml in the tomcat-dir/conf
  3. Add the below <ResourceLink> inside the <Context> tag.
<ResourceLink name="jdbc/mydb" 
              type="javax.sql.DataSource" />
  1. Save the context.xml
  2. Open the hibernate-cfg.xml file and add and remove below properties.
<property name="connection.datasource">java:comp/env/jdbc/mydb</property>

<!--<property name="connection.url">jdbc:mysql://localhost:3306/mydb</property> -->
<!--<property name="connection.username">root</property> -->
<!--<property name="connection.password"></property> -->
  1. Save the file and put latest .WAR file in tomcat.
  2. Restart the tomcat. the DB connection will work.

how to force maven to update local repo

If you are installing into local repository, there is no special index/cache update needed.

Make sure that:

  1. You have installed the first artifact in your local repository properly. Simply copying the file to .m2 may not work as expected. Make sure you install it by mvn install

  2. The dependency in 2nd project is setup correctly. Check on any typo in groupId/artifactId/version, or unmatched artifact type/classifier.

Make JQuery UI Dialog automatically grow or shrink to fit its contents

Update: As of jQuery UI 1.8, the working solution (as mentioned in the second comment) is to use:

width: 'auto'

Use the autoResize:true option. I'll illustrate:

  <div id="whatup">
    <div id="inside">Hi there.</div>
      "resize", "auto"
     setTimeout(function() {
        setTimeout(arguments.callee, 1000);
      }, 1000);

Here's a working example:

Upgrade to python 3.8 using conda

Now that the new anaconda individual edition 2020 distribution is out, the procedure that follows is working:

Update conda in your base env:

conda update conda

Create a new environment for Python 3.8, specifying anaconda for the full distribution specification, not just the minimal environment:

conda create -n py38 python=3.8 anaconda

Activate the new environment:

conda activate py38

python --version
Python 3.8.1

Number of packages installed: 303

Or you can do:

conda create -n py38 anaconda=2020.02 python=3.8

--> UPDATE: Finally, Anaconda3-2020.07 is out with core Python 3.8.3

You can download Anaconda with Python 3.8 from

PHP: Best way to check if input is a valid number?

The most secure way

if(preg_replace('/^(\-){0,1}[0-9]+(\.[0-9]+){0,1}/', '', $value) == ""){
  //if all made of numbers "-" or ".", then yes is number;

Add element to a JSON file?

alternatively you can do

iter(data).next()['f'] = var

HTML5 : Iframe No scrolling?

In HTML5 there is no scrolling attribute because "its function is better handled by CSS" see for other changes. Well and the CSS solution:

CSS solution:

HTML4's scrolling="no" is kind of an alias of the CSS's overflow: hidden, to do so it is important to set size attributes width/height:

  width: 250px; /*or any other size*/
  height: 300px; /*or any other size*/
  overflow: hidden;

Add this class to your iframe and you're done:

<iframe src="" class="noScrolling"></iframe>

! IMPORTANT NOTE ! : overflow: hidden for <iframe> is not fully supported by all modern browsers yet(even chrome doesn't support it yet) so for now (2013) it's still better to use Transitional version and use scrolling="no" and overflow:hidden at the same time :)

UPDATE 2020: the above is still true, oveflow for iframes is still not supported by all majors

Fastest way to Remove Duplicate Value from a list<> by lambda

A simple intuitive implementation

public static List<PointF> RemoveDuplicates(List<PointF> listPoints)
    List<PointF> result = new List<PointF>();

    for (int i = 0; i < listPoints.Count; i++)
        if (!result.Contains(listPoints[i]))

    return result;

"A lambda expression with a statement body cannot be converted to an expression tree"

The LINQ to SQL return object were implementing IQueryable interface. So for Select method predicate parameter you should only supply single lambda expression without body.

This is because LINQ for SQL code is not execute inside program rather than on remote side like SQL server or others. This lazy loading execution type were achieve by implementing IQueryable where its expect delegate is being wrapped in Expression type class like below.


Expression tree do not support lambda expression with body and its only support single line lambda expression like var id = cols.Select( col => );

So if you try the following code won't works.

Expression<Func<int,int>> function = x => {
    return x * 2;

The following will works as per expected.

Expression<Func<int,int>> function = x => x * 2;

Download File Using Javascript/jQuery

I have had good results with using a FORM tag since it works everywhere and you don't have to create temporarily files on server. The method works like this.

On the client side (page HTML) you create an invisible form like this

<form method="POST" action="/download.php" target="_blank" id="downloadForm">
    <input type="hidden" name="data" id="csv">

Then you add this Javascript code to your button:

$('#button').click(function() {
     $('#csv').val('---your data---');

The on the server-side you have the following PHP code in download.php:

header('Content-Type: text/csv');
header('Content-Description: File Transfer');
header('Content-Type: application/octet-stream');
header('Content-Disposition: attachment; filename=out.csv');
header('Content-Transfer-Encoding: binary');
header('Connection: Keep-Alive');
header('Expires: 0');
header('Cache-Control: must-revalidate, post-check=0, pre-check=0');
header('Pragma: public');
header('Content-Length: ' . strlen($data));

echo $_REQUEST['data'];

You can even create zip files of your data like this:


$file = tempnam("tmp", "zip");

$zip = new ZipArchive();
$zip->open($file, ZipArchive::OVERWRITE);
$zip->addFromString('test.csv', $_REQUEST['data']);

header('Content-Type: application/zip');
header('Content-Length: ' . filesize($file));
header('Content-Disposition: attachment; filename=""');

The best part is it does not leave any residual files on your server since everything is created and destroyed on the fly!

How do I use Assert to verify that an exception has been thrown?

Be wary of using ExpectedException, as it can lead to several pitfalls as demonstrated here:

And here:

If you need to test for exceptions, there are less frowned upon ways. You can use the try{act/fail}catch{assert} method, which can be useful for frameworks that don't have direct support for exception tests other than ExpectedException.

A better alternative is to use xUnit.NET, which is a very modern, forward looking, and extensible unit testing framework that has learned from all the others mistakes, and improved. One such improvement is Assert.Throws, which provides a much better syntax for asserting exceptions.

You can find xUnit.NET at github:

How to upload file using Selenium WebDriver in Java

Find the tag as type="file". this the main tag which is supported by selenium. If you are able to build your XPath with same when it is recommended.

  • use sendkeys for the button having browse option(The button which will open your window box to select files)
  • Now click on the button which is going to upload your file

As below :-


For multiple file upload put all files one by one by sendkeys and then click on upload

driver.findElement(By.xpath("//button[@id='Upload']")).click(); // Upload button

Why is Visual Studio 2010 not able to find/open PDB files?

I'm pretty sure those are warnings, not errors. Your project should still run just fine.

However, since you should always try to fix compiler warnings, let's see what we can discover. I'm not at all familiar with OpenCV, and you don't link to the wiki tutorial that you're following. But it looks to me like the problem is that you're running a 64-bit version of Windows (as evidenced by the "SysWOW64" folder in the path to the DLL files), but the OpenCV stuff that you're trying is built for a 32-bit platform. So you might need to rebuild the project using CMake, as explained here.

More specifically, the files that are listed are Windows system files. PDB files contain debugging information that Visual Studio uses to allow you to step into and debug compiled code. You don't actually need the PDB files for system libraries to be able to debug your own code. But if you want, you can download the symbols for the system libraries as well. Go to the "Debug" menu, click on "Options and Settings", and scroll down the listbox on the right until you see "Enable source server support". Make sure that option is checked. Then, in the treeview to the left, click on "Symbols", and make sure that the "Microsoft Symbol Servers" option is selected. Click OK to dismiss the dialog, and then try rebuilding.

MVC 3: How to render a view without its layout page when loaded via ajax?

All you need is to create two layouts:

  1. an empty layout

  2. main layout

Then write the code below in _viewStart file:

   if (Request.IsAjaxRequest())
      Layout = "~/Areas/Dashboard/Views/Shared/_emptyLayout.cshtml";
      Layout = "~/Areas/Dashboard/Views/Shared/_Layout.cshtml";

of course, maybe it is not the best solution

Load local javascript file in chrome for testing?

Running a simple local HTTP server

To test such examples, one needs a local webserver. One of the easiest ways to do this for our purposes is to use Python's SimpleHTTPServer (or http.server, depending on the version of Python installed.)

# Install Python & try one of the following depending on your python version. if the version is 3.X
python3 -m http.server
# On windows try "python" instead of "python3", or "py -3"
# If Python version is 2.X
python -m SimpleHTTPServer

Spring mvc @PathVariable

If you have url with path variables, example where 12 is the id and create is the variable you want to use for specifying your execution for instance in using a single form to do an update and create, you do this in your controller.

   @PostMapping(value = "/item/{id}/{method}")
    public String getForm(@PathVariable("id") String itemId ,  
        @PathVariable("method") String methodCall , Model model){


      return "path to your form";

Which @NotNull Java annotation should I use?

For Android projects you should use and These and other helpful Android-specific annotations are available in the Support Library.


The support library itself has also been annotated with these annotations, so as a user of the support library, Android Studio will already check your code and flag potential problems based on these annotations.

Reverse Contents in Array

void reverse(int [], int);
void printarray(int [], int );
int main ()
    const int SIZE = 10;
    int arr [SIZE] = {1, 2, 3, 4, 5, 6, 7, 8, 9, 10};

    cout<<"Before reverse\n";
    printarray(arr, SIZE);
    reverse(arr, SIZE);
    cout<<"After reverse\n";
    printarray(arr, SIZE);

    return 0;

void printarray(int arr[], int count)
    for(int i = 0; i < count; ++i)
        cout<<arr[i]<<' ';


void reverse(int arr[], int count)
   int temp;
   for (int i = 0; i < count/2; ++i)
      temp = arr[i];
      arr[i] = arr[count-i-1];
      arr[count-i-1] = temp;

back button callback in navigationController in iOS

William Jockusch's answer solve this problem with easy trick.

-(void) viewWillDisappear:(BOOL)animated {
    if ([self.navigationController.viewControllers indexOfObject:self]==NSNotFound) {
       // back button was pressed.  We know this is true because self is no longer
       // in the navigation stack.  
    [super viewWillDisappear:animated];

Convert timestamp in milliseconds to string formatted time in Java


logEvent.timeStamp / (1000*60*60)

will give you hours, not minutes. Try:

logEvent.timeStamp / (1000*60)

and you will end up with the same answer as


Query an object array using linq


using System.Linq;

to the top of your file.

And then:

Car[] carList = ...
var carMake = 
    from item in carList
    where item.Model == "bmw" 
    select item.Make;

or if you prefer the fluent syntax:

var carMake = carList
    .Where(item => item.Model == "bmw")
    .Select(item => item.Make);

Things to pay attention to:

  • The usage of item.Make in the select clause instead if s.Make as in your code.
  • You have a whitespace between item and .Model in your where clause

Convert String XML fragment to Document Node in Java

...and if you're using purely XOM, something like this:

    String xml = "<fakeRoot>" + xml + "</fakeRoot>";
    Document doc = new Builder( false ).build( xml, null );
    Nodes children = doc.getRootElement().removeChildren();
    for( int ix = 0; ix < children.size(); ix++ ) {
        otherDocumentElement.appendChild( children.get( ix ) );

XOM uses fakeRoot internally to do pretty much the same, so it should be safe, if not exactly elegant.

How to force reloading a page when using browser back button?

Use following meta tag in your html header file, This works for me.

<meta http-equiv="Pragma" content="no-cache">

Setting up PostgreSQL ODBC on Windows

First you download ODBC driver then you installed it.After that go to START->Program->Administrative tools then you select Data Source ODBC then you double click on the same after that you select PostgreSQL 30 then you select configure then you provide proper details such as db name user Id host name password of the same database in this way you will configured your DSN connection.After That you will check SSL should be allow .

Then you go on next tab system DSN then you select ADD tabthen select postgreSQL_ANSI_64X ODBC after you that you have created PostgreSQL ODBC connection.

Getting the source of a specific image element with jQuery

To select and element where you know only the attribute value you can use the below jQuery script

var src = $('.conversation_img[alt="example"]').attr('src');

Please refer the jQuery Documentation for attribute equals selectors

Please also refer to the example in Demo

Following is the code incase you are not able to access the demo..


    <img alt="example" src="\images\show.jpg" />
    <img  alt="exampleAll" src="\images\showAll.jpg" />  



var src = $('img[alt="example"]').attr('src');
alert("source of image with alternate text = example - " + src);

var srcAll = $('img[alt="exampleAll"]').attr('src');
alert("source of image with alternate text = exampleAll - " + srcAll );

Output will be

Two Alert messages each having values

  1. source of image with alternate text = example - \images\show.jpg
  2. source of image with alternate text = exampleAll - \images\showAll.jpg

'this' vs $scope in AngularJS controllers

I recommend you to read the following post: AngularJS: "Controller as" or "$scope"?

It describes very well the advantages of using "Controller as" to expose variables over "$scope".

I know you asked specifically about methods and not variables, but I think that it's better to stick to one technique and be consistent with it.

So for my opinion, because of the variables issue discussed in the post, it's better to just use the "Controller as" technique and also apply it to the methods.

Is there an XSLT name-of element?

Nobody did point the subtle difference in the semantics of the functions name() and local-name().

  • name(someNode) returns the full name of the node, and that includes the prefix and colon in case the node is an element or an attribute.
  • local-name(someNode) returns only the local name of the node, and that doesn't include the prefix and colon in case the node is an element or an attribute.

Therefore, in situations where a name may belong to two different namespaces, one must use the name() function in order for these names to be still distinguished.

And, BTW, it is possible to specify both functions without any argument:

name() is an abbreviation for name(.)

local-name() is an abbreviation for local-name(.)

Finally, do remember that not only elements and attributes have names, these two functions can also be used on PIs and on these they are identical).

How to include Authorization header in cURL POST HTTP Request in PHP?

@jason-mccreary is totally right. Besides I recommend you this code to get more info in case of malfunction:

$rest = curl_exec($crl);

if ($rest === false)
    // throw new Exception('Curl error: ' . curl_error($crl));
    print_r('Curl error: ' . curl_error($crl));



To debug you can set CURLOPT_HEADER to true to check HTTP response with firebug::net or similar.

curl_setopt($crl, CURLOPT_HEADER, true);


About Curl error: SSL certificate problem, verify that the CA cert is OK try adding this headers (just to debug, in a production enviroment you should keep these options in true):

curl_setopt($crl, CURLOPT_SSL_VERIFYHOST, false);
curl_setopt($crl, CURLOPT_SSL_VERIFYPEER, false);

Switch statement multiple cases in JavaScript

The problem with the above approaches, is that you have to repeat the several cases every time you call the function which has the switch. A more robust solution is to have a map or a dictionary.

Here is an example:

// The Map, divided by concepts
var dictionary = {
  timePeriod: {
    'month': [1, 'monthly', 'mensal', 'mês'],
    'twoMonths': [2, 'two months', '2 months', 'bimestral', 'bimestre'],
    'trimester': [3, 'trimesterly', 'quarterly', 'trimestral'],
    'semester': [4, 'semesterly', 'semestral', 'halfyearly'],
    'year': [5, 'yearly', 'annual', 'ano']
  distance: {
    'km': [1, 'kms', 'kilometre', 'kilometers', 'kilometres'],
    'mile': [2, 'mi', 'miles'],
    'nordicMile': [3, 'Nordic mile', 'mil (10 km)', 'Scandinavian mile']
  fuelAmount: {
    'ltr': [1, 'l', 'litre', 'Litre', 'liter', 'Liter'],
    'gal (imp)': [2, 'imp gallon', 'imperial gal', 'gal (UK)'],
    'gal (US)': [3, 'US gallon', 'US gal'],
    'kWh': [4, 'KWH']

// This function maps every input to a certain defined value
function mapUnit (concept, value) {
  for (var key in dictionary[concept]) {
    if (key === value ||
      dictionary[concept][key].indexOf(value) !== -1) {
      return key
  throw Error('Uknown "'+value+'" for "'+concept+'"')

// You would use it simply like this
mapUnit("fuelAmount", "ltr") // => ltr
mapUnit("fuelAmount", "US gal") // => gal (US)
mapUnit("fuelAmount", 3) // => gal (US)
mapUnit("distance", "kilometre") // => km

// Now you can use the switch statement safely without the need
// to repeat the combinations every time you call the switch
var foo = 'monthly'
switch (mapUnit ('timePeriod', foo)) {
  case 'month':
  case 'twoMonths':
  case 'trimester':
  case 'semester':
  case 'year':
    throw Error('error')

How do I load a file into the python console?

For Python 2 give execfile a try. (See other answers for Python 3)


Example usage:
Let's use "copy con" to quickly create a small script file...

C:\junk>copy con
a = [9, 42, 888]
b = len(a)
        1 file(s) copied.

...and then let's load this script like so:

Python 2.7.1 (r271:86832, Nov 27 2010, 18:30:46) [MSC v.1500 32 bit (Intel)] on win32
Type "help", "copyright", "credits" or "license" for more information.
>>> execfile('')
>>> a
[9, 42, 888]
>>> b

Check if a string has white space

This function checks for other types of whitespace, not just space (tab, carriage return, etc.)

import some from 'lodash/fp/some'
const whitespaceCharacters = [' ', '  ',
  '\b', '\t', '\n', '\v', '\f', '\r', `\"`, `\'`, `\\`,
  '\u0008', '\u0009', '\u000A', '\u000B', '\u000C',
'\u000D', '\u0020','\u0022', '\u0027', '\u005C',
'\u00A0', '\u2028', '\u2029', '\uFEFF']
const hasWhitespace = char => some(
  w => char.indexOf(w) > -1,

console.log(hasWhitespace('a')); // a, false
console.log(hasWhitespace(' ')); // space, true
console.log(hasWhitespace(' ')); // tab, true
console.log(hasWhitespace('\r')); // carriage return, true

If you don't want to use Lodash, then here is a simple some implementation with 2 s:

const ssome = (predicate, list) =>
  const len = list.length;
  for(const i = 0; i<len; i++)
    if(predicate(list[i]) === true) {
      return true;
  return false;

Then just replace some with ssome.

const hasWhitespace = char => some(
  w => char.indexOf(w) > -1,

For those in Node, use:

const { some } = require('lodash/fp');

Get the records of last month in SQL server

SET @StartDate = dateadd(mm, -1, getdate())
SET @StartDate = dateadd(dd, datepart(dd, getdate())*-1, @StartDate)
SET @EndDate = dateadd(mm, 1, @StartDate)
set @StartDate = DATEADD(dd, 1 , @StartDate)

How can I replace a regex substring match in Javascript?

I think the simplest way to achieve your goal is this:

var str   = 'asd-0.testing';
var regex = /(asd-)(\d)(\.\w+)/;
var anyNumber = 1;
var res = str.replace(regex, `$1${anyNumber}$3`);

How do I enable index downloads in Eclipse for Maven dependency search?

Tick 'Full Index Enabled' and then 'Rebuild Index' of the central repository in 'Global Repositories' under Window > Show View > Other > Maven > Maven Repositories, and it should work.

The rebuilding may take a long time depending on the speed of your internet connection, but eventually it works.

Anonymous method in Invoke call

I had problems with the other suggestions because I want to sometimes return values from my methods. If you try to use MethodInvoker with return values it doesn't seem to like it. So the solution I use is like this (very happy to hear a way to make this more succinct - I'm using 2.0):

    // Create delegates for the different return types needed.
    private delegate void VoidDelegate();
    private delegate Boolean ReturnBooleanDelegate();
    private delegate Hashtable ReturnHashtableDelegate();

    // Now use the delegates and the delegate() keyword to create 
    // an anonymous method as required

    // Here a case where there's no value returned:
    public void SetTitle(string title)
        myWindow.Invoke(new VoidDelegate(delegate()
            myWindow.Text = title;

    // Here's an example of a value being returned
    public Hashtable CurrentlyLoadedDocs()
        return (Hashtable)myWindow.Invoke(new ReturnHashtableDelegate(delegate()
            return myWindow.CurrentlyLoadedDocs;

Laravel: getting a a single value from a MySQL query

[EDIT] The expected output of the pluck function has changed from Laravel 5.1 to 5.2. Hence why it is marked as deprecated in 5.1

In Laravel 5.1, pluck gets a single column's value from the first result of a query.

In Laravel 5.2, pluck gets an array with the values of a given column. So it's no longer deprecated, but it no longer do what it used to.

So short answer is use the value function if you want one column from the first row and you are using Laravel 5.1 or above.

Thanks to Tomas Buteler for pointing this out in the comments.

[ORIGINAL] For anyone coming across this question who is using Laravel 5.1, pluck() has been deprecated and will be removed completely in Laravel 5.2.

Consider future proofing your code by using value() instead.

return DB::table('users')->where('username', $username)->value('groupName');

Authentication issues with WWW-Authenticate: Negotiate

Putting this information here for future readers' benefit.

  • 401 (Unauthorized) response header -> Request authentication header

  • Here are several WWW-Authenticate response headers. (The full list is at IANA: HTTP Authentication Schemes.)

    • WWW-Authenticate: Basic-> Authorization: Basic + token - Use for basic authentication
    • WWW-Authenticate: NTLM-> Authorization: NTLM + token (2 challenges)
    • WWW-Authenticate: Negotiate -> Authorization: Negotiate + token - used for Kerberos authentication
      • By the way: IANA has this angry remark about Negotiate: This authentication scheme violates both HTTP semantics (being connection-oriented) and syntax (use of syntax incompatible with the WWW-Authenticate and Authorization header field syntax).

You can set the Authorization: Basic header only when you also have the WWW-Authenticate: Basic header on your 401 challenge.

But since you have WWW-Authenticate: Negotiate this should be the case for Kerberos based authentication.

CSS transition effect makes image blurry / moves image 1px, in Chrome?

None of this worked, what worked for me is scaling image down.

So depending on what size you want the image or what resoultion your image is, you can do something like this:

.ok {
      transform: perspective(100px) rotateY(0deg) scale(0.5);
      transition: transform 1s;
      transform: perspective(100px) rotateY(-10deg) scale(0.5);

/* Demo Preview Stuff */
.bad {
   max-width: 320px;
   transform: perspective(100px) rotateY(0deg);
   transition: transform 1s;
      transform: perspective(100px) rotateY(-10deg);

div {
     text-align: center;
     position: relative;
     display: flex;
    position: absolute;
    bottom: 30px;
    left: 0;
    right: 0;
.b {
    display: flex;
<h2>Hover on images</h2>
<div class="b">
  <img class="ok" src=''>

  <img class="bad" src=''>



The image should be scaled down, make sure you have a big image resoultion

Is #pragma once a safe include guard?

I wish #pragma once (or something like it) had been in the standard. Include guards aren't a real big deal (but they do seem to be a little difficult to explain to people learning the language), but it seems like a minor annoyance that could have been avoided.

In fact, since 99.98% of the time, the #pragma once behavior is the desired behavior, it would have been nice if preventing multiple inclusion of a header was automatically handled by the compiler, with a #pragma or something to allow double including.

But we have what we have (except that you might not have #pragma once).

CSS: stretching background image to 100% width and height of screen?

html, body {
    min-height: 100%;

Will do the trick.

By default, even html and body are only as big as the content they hold, but never more than the width/height of the windows. This can often lead to quite strange results.

You might also want to read

There are some great ways do achieve a very good and scalable full background image.

How to empty a redis database?

open your Redis cli and There two possible option that you could use:

FLUSHDB - Delete all the keys of the currently selected DB. FLUSHALL - Delete all the keys of all the existing databases, not just the currently selected one.

Android Button Onclick

If you write like this in Button tag in xml file : android:onClick="setLogin" then

Do like this:

<?xml version="1.0" encoding="utf-8"?>
<LinearLayout xmlns:android=""
android:orientation="vertical" >

    android:onClick="onClickBtn" />


and in Code part:

public class StartUpActivity extends Activity 
    public void onCreate(Bundle savedInstanceState) 

    public void onClickBtn(View v)
        Toast.makeText(this, "Clicked on Button", Toast.LENGTH_LONG).show();

and no need all this:

 Button button = (Button) findViewById(;
 button.setOnClickListener(new OnClickListener() {

    public void onClick(View v) {
        // TODO Auto-generated method stub


Check it once;

What are all the user accounts for IIS/ASP.NET and how do they differ?

This is a very good question and sadly many developers don't ask enough questions about IIS/ASP.NET security in the context of being a web developer and setting up IIS. So here goes....

To cover the identities listed:


This is analogous to the old IIS6 IIS_WPG group. It's a built-in group with it's security configured such that any member of this group can act as an application pool identity.


This account is analogous to the old IUSR_<MACHINE_NAME> local account that was the default anonymous user for IIS5 and IIS6 websites (i.e. the one configured via the Directory Security tab of a site's properties).

For more information about IIS_IUSRS and IUSR see:

Understanding Built-In User and Group Accounts in IIS 7


If an application pool is configured to run using the Application Pool Identity feature then a "synthesised" account called IIS AppPool\<pool name> will be created on the fly to used as the pool identity. In this case there will be a synthesised account called IIS AppPool\DefaultAppPool created for the life time of the pool. If you delete the pool then this account will no longer exist. When applying permissions to files and folders these must be added using IIS AppPool\<pool name>. You also won't see these pool accounts in your computers User Manager. See the following for more information:

Application Pool Identities

ASP.NET v4.0: -

This will be the Application Pool Identity for the ASP.NET v4.0 Application Pool. See DefaultAppPool above.


The NETWORK SERVICE account is a built-in identity introduced on Windows 2003. NETWORK SERVICE is a low privileged account under which you can run your application pools and websites. A website running in a Windows 2003 pool can still impersonate the site's anonymous account (IUSR_ or whatever you configured as the anonymous identity).

In ASP.NET prior to Windows 2008 you could have ASP.NET execute requests under the Application Pool account (usually NETWORK SERVICE). Alternatively you could configure ASP.NET to impersonate the site's anonymous account via the <identity impersonate="true" /> setting in web.config file locally (if that setting is locked then it would need to be done by an admin in the machine.config file).

Setting <identity impersonate="true"> is common in shared hosting environments where shared application pools are used (in conjunction with partial trust settings to prevent unwinding of the impersonated account).

In IIS7.x/ASP.NET impersonation control is now configured via the Authentication configuration feature of a site. So you can configure to run as the pool identity, IUSR or a specific custom anonymous account.


The LOCAL SERVICE account is a built-in account used by the service control manager. It has a minimum set of privileges on the local computer. It has a fairly limited scope of use:

LocalService Account


You didn't ask about this one but I'm adding for completeness. This is a local built-in account. It has fairly extensive privileges and trust. You should never configure a website or application pool to run under this identity.

LocalSystem Account

In Practice:

In practice the preferred approach to securing a website (if the site gets its own application pool - which is the default for a new site in IIS7's MMC) is to run under Application Pool Identity. This means setting the site's Identity in its Application Pool's Advanced Settings to Application Pool Identity:

enter image description here

In the website you should then configure the Authentication feature:

enter image description here

Right click and edit the Anonymous Authentication entry:

enter image description here

Ensure that "Application pool identity" is selected:

enter image description here

When you come to apply file and folder permissions you grant the Application Pool identity whatever rights are required. For example if you are granting the application pool identity for the ASP.NET v4.0 pool permissions then you can either do this via Explorer:

enter image description here

Click the "Check Names" button:

enter image description here

Or you can do this using the ICACLS.EXE utility:

icacls c:\wwwroot\mysite /grant "IIS AppPool\ASP.NET v4.0":(CI)(OI)(M)

...or...if you site's application pool is called BobsCatPicBlogthen:

icacls c:\wwwroot\mysite /grant "IIS AppPool\BobsCatPicBlog":(CI)(OI)(M)

I hope this helps clear things up.


I just bumped into this excellent answer from 2009 which contains a bunch of useful information, well worth a read:

The difference between the 'Local System' account and the 'Network Service' account?

psql: FATAL: Ident authentication failed for user "postgres"

If you've done all this and it still doesn't work, check the expiry for that user:

Postgres password authentication fails

How do I alter the precision of a decimal column in Sql Server?

ALTER TABLE (Your_Table_Name) MODIFY (Your_Column_Name) DATA_TYPE();

For you problem:

ALTER TABLE (Your_Table_Name) MODIFY (Your_Column_Name) DECIMAL(Precision, Scale); 

Checking for an empty field with MySQL

There's a difference between an empty string (email != "") and NULL. NULL is null and an Empty string is something.

Renaming branches remotely in Git

I don't know if this is right or wrong, but I pushed the "old name" of the branch to the "new name" of the branch, then deleted the old branch entirely with the following two lines:

git push origin old_branch:new_branch
git push origin :old_branch

Generate GUID in MySQL for existing Data?


UPDATE tablename   SET columnName = UUID()


UPDATE tablename   SET columnName = SYS_GUID();


UPDATE tablename   SET columnName = NEWID();;

How can I wrap text in a label using WPF?

To wrap text in the label control, change the the template of label as follows:

<Style x:Key="ErrorBoxStyle" TargetType="{x:Type Label}">
    <Setter Property="BorderBrush" Value="#FFF08A73"/>
    <Setter Property="BorderThickness" Value="1"/>
    <Setter Property="Foreground" Value="Red"/>
    <Setter Property="Background" Value="#FFFFE3DF"/>
    <Setter Property="FontWeight" Value="Bold"/>
    <Setter Property="Padding" Value="5"/>
    <Setter Property="HorizontalContentAlignment" Value="Left"/>
    <Setter Property="VerticalContentAlignment" Value="Top"/>
    <Setter Property="Template">
            <ControlTemplate TargetType="{x:Type Label}">
                <Border BorderBrush="{TemplateBinding BorderBrush}" BorderThickness="{TemplateBinding BorderThickness}" Background="{TemplateBinding Background}" Padding="{TemplateBinding Padding}" SnapsToDevicePixels="true" CornerRadius="5" HorizontalAlignment="Stretch">
                    <TextBlock TextWrapping="Wrap" Text="{TemplateBinding Content}"/>

How to remove specific elements in a numpy array

list comprehension could be an interesting approach as well.

a = np.array([1, 2, 3, 4, 5, 6, 7, 8, 9])
index = np.array([2, 3, 6]) #index is changed to an array.  
out = [val for i, val in enumerate(a) if all(i != index)]
>>> [1, 2, 5, 6, 8, 9]

How to show current time in JavaScript in the format HH:MM:SS?

new Date().toLocaleTimeString('it-IT')

The it-IT locale happens to pad the hour if needed and omits PM or AM 01:33:01

How can Perl's print add a newline by default?

Perhaps you want to change your output record separator to linefeed with:

local $\ = "\n";

$ perl -e 'print q{hello};print q{goodbye}' | od -c
0000000    h   e   l   l   o   g   o   o   d   b   y   e                
$ perl -e '$\ = qq{\n}; print q{hello};print q{goodbye}' | od -c
0000000    h   e   l   l   o  \n   g   o   o   d   b   y   e  \n        

Update: my answer speaks to capability rather than advisability. I don't regard adding "\n" at the end of lines to be a "pesky" chore, but if someone really wants to avoid them, this is one way. If I had to maintain a bit of code that uses this technique, I'd probably refactor it out pronto.

How to convert from []byte to int in Go Programming

var bs []byte
value, _ := strconv.ParseInt(string(bs), 10, 64)

Filter Java Stream to 1 and only 1 element

I am using those two collectors:

public static <T> Collector<T, ?, Optional<T>> zeroOrOne() {
    return Collectors.reducing((a, b) -> {
        throw new IllegalStateException("More than one value was returned");

public static <T> Collector<T, ?, T> onlyOne() {
    return Collectors.collectingAndThen(zeroOrOne(), Optional::get);

CSS Box Shadow - Top and Bottom Only

So this is my first answer here, and because I needed something similar I did with pseudo elements for 2 inner shadows, and an extra DIV for an upper outer shadow. Don't know if this is the best solutions but maybe it will help someone.


<div class="shadow-block">
    <div class="shadow"></div>
    <div class="overlay">
        <div class="overlay-inner">
            content here


.overlay {
    background: #f7f7f4;
    height: 185px;
    overflow: hidden;
    position: relative;
    width: 100%; 

.overlay:before {
    border-radius: 50% 50% 50% 50%;
    box-shadow: 0 0 50px 2px rgba(1, 1, 1, 0.6);
    content: " ";
    display: block;
    margin: 0 auto;
    width: 80%;

.overlay:after {
    border-radius: 50% 50% 50% 50%;
    box-shadow: 0 0 70px 5px rgba(1, 1, 1, 0.5);
    content: "-";
    display: block;
    margin: 0 auto;
    position: absolute;
    bottom: -65px;
    left: -50%;
    right: -50%;
    width: 80%;

.shadow {
    position: relative;
    margin: 0 0 -22px 0;
    -webkit-box-shadow: 0px 0px 50px 3px rgba(1, 1, 1, 0.6);
    box-shadow: 0px 0px 50px 3px rgba(1, 1, 1, 0.6);
    border-radius: 50%;

Java Read Large Text File With 70million line of text

If you are looking out at performance, you could have a look at the java.nio.* packages - those are supposedly faster than*

Can't find bundle for base name

java.util.MissingResourceException: Can't find bundle for base name
    org.jfree.chart.LocalizationBundle, locale en_US

To the point, the exception message tells in detail that you need to have either of the following files in the classpath:






Also see the official Java tutorial about resourcebundles for more information.

But as this is actually a 3rd party managed properties file, you shouldn't create one yourself. It should be already available in the JFreeChart JAR file. So ensure that you have it available in the classpath during runtime. Also ensure that you're using the right version, the location of the propertiesfile inside the package tree might have changed per JFreeChart version.

When executing a JAR file, you can use the -cp argument to specify the classpath. E.g.:

java -jar -cp c:/path/to/jfreechart.jar yourfile.jar

Alternatively you can specify the classpath as class-path entry in the JAR's manifest file. You can use in there relative paths which are relative to the JAR file itself. Do not use the %CLASSPATH% environment variable, it's ignored by JAR's and everything else which aren't executed with java.exe without -cp, -classpath and -jar arguments.

How to convert an integer (time) to HH:MM:SS::00 in SQL Server 2008?

This will work:

DECLARE @MS INT = 235216
select cast(dateadd(ms, @MS, '00:00:00') AS TIME(3))

(where ms is just a number of seconds not a timeformat)