Programs & Examples On #Xamlx

AngularJS ng-class if-else expression

A workaround of mine is to manipulate a model variable just for the ng-class toggling:

For example, I want to toggle class according to the state of my list:

1) Whenever my list is empty, I update my model:

$scope.extract = function(removeItemId) {
    $scope.list= jQuery.grep($scope.list, function(item){return item.id != removeItemId});
    if (!$scope.list.length) {
        $scope.liststate = "empty";
    }
}

2) Whenever my list is not empty, I set another state

$scope.extract = function(item) {
    $scope.list.push(item);
    $scope.liststate = "notempty";
}

3) When my list is not ever touched, I want to give another class (this is where the page is initiated):

$scope.liststate = "init";

3) I use this additional model on my ng-class:

ng-class="{'bg-empty': liststate == 'empty', 'bg-notempty': liststate == 'notempty', 'bg-init': liststate = 'init'}"

Better solution without exluding fields from Binding

You should not use your domain models in your views. ViewModels are the correct way to do it.

You need to map your domain model's necessary fields to viewmodel and then use this viewmodel in your controllers. This way you will have the necessery abstraction in your application.

If you never heard of viewmodels, take a look at this.

How do I make an HTTP request in Swift?

Details

  • Xcode 9.2, Swift 4
  • Xcode 10.2.1 (10E1001), Swift 5

Info.plist

NSAppTransportSecurity

Add to the info plist:

<key>NSAppTransportSecurity</key>
<dict>
    <key>NSAllowsArbitraryLoads</key>
    <true/>
</dict>

Alamofire Sample

Alamofire

import Alamofire

class AlamofireDataManager {
    fileprivate let queue: DispatchQueue
    init(queue: DispatchQueue) { self.queue = queue }

    private func createError(message: String, code: Int) -> Error {
        return NSError(domain: "dataManager", code: code, userInfo: ["message": message ])
    }

    private func make(session: URLSession = URLSession.shared, request: URLRequest, closure: ((Result<[String: Any]>) -> Void)?) {
        Alamofire.request(request).responseJSON { response in
            let complete: (Result<[String: Any]>) ->() = { result in DispatchQueue.main.async { closure?(result) } }
            switch response.result {
                case .success(let value): complete(.success(value as! [String: Any]))
                case .failure(let error): complete(.failure(error))
            }
        }
    }

    func searchRequest(term: String, closure: ((Result<[String: Any]>) -> Void)?) {
        guard let url = URL(string: "https://itunes.apple.com/search?term=\(term.replacingOccurrences(of: " ", with: "+"))") else { return }
        let request = URLRequest(url: url)
        make(request: request) { response in closure?(response) }
    }
}

Usage of Alamofire sample

private lazy var alamofireDataManager = AlamofireDataManager(queue: DispatchQueue(label: "DataManager.queue", qos: .utility))
//.........

alamofireDataManager.searchRequest(term: "jack johnson") { result in
      print(result.value ?? "no data")
      print(result.error ?? "no error")
}

URLSession Sample

import Foundation

class DataManager {

    fileprivate let queue: DispatchQueue
        init(queue: DispatchQueue) { self.queue = queue }

    private func createError(message: String, code: Int) -> Error {
        return NSError(domain: "dataManager", code: code, userInfo: ["message": message ])
    }

    private func make(session: URLSession = URLSession.shared, request: URLRequest, closure: ((_ json: [String: Any]?, _ error: Error?)->Void)?) {
        let task = session.dataTask(with: request) { [weak self] data, response, error in
            self?.queue.async {
                let complete: (_ json: [String: Any]?, _ error: Error?) ->() = { json, error in DispatchQueue.main.async { closure?(json, error) } }

                guard let self = self, error == nil else { complete(nil, error); return }
                guard let data = data else { complete(nil, self.createError(message: "No data", code: 999)); return }

                do {
                    if let json = try JSONSerialization.jsonObject(with: data, options: .mutableContainers) as? [String: Any] {
                        complete(json, nil)
                    }
                } catch let error { complete(nil, error); return }
            }
        }

        task.resume()
    }

    func searchRequest(term: String, closure: ((_ json: [String: Any]?, _ error: Error?)->Void)?) {
        let url = URL(string: "https://itunes.apple.com/search?term=\(term.replacingOccurrences(of: " ", with: "+"))")
        let request = URLRequest(url: url!)
        make(request: request) { json, error in closure?(json, error) }
    }
}

Usage of URLSession sample

private lazy var dataManager = DataManager(queue: DispatchQueue(label: "DataManager.queue", qos: .utility))
// .......
dataManager.searchRequest(term: "jack johnson") { json, error  in
      print(error ?? "nil")
      print(json ?? "nil")
      print("Update views")
}

Results

enter image description here

How to determine the Schemas inside an Oracle Data Pump Export file

The running the impdp command to produce an sqlfile, you will need to run it as a user which has the DATAPUMP_IMP_FULL_DATABASE role.

Or... run it as a low privileged user and use the MASTER_ONLY=YES option, then inspect the master table. e.g.

select value_t 
from SYS_IMPORT_TABLE_01 
where name = 'CLIENT_COMMAND' 
and process_order = -59;

col object_name for a30
col processing_status head STATUS for a6
col processing_state head STATE for a5
select distinct
  object_schema,
  object_name,
  object_type,
  object_tablespace,
  process_order,
  duplicate,
  processing_status,
  processing_state
from sys_import_table_01
where process_order > 0
and object_name is not null
order by object_schema, object_name
/

http://download.oracle.com/otndocs/products/database/enterprise_edition/utilities/pdf/oow2011_dp_mastering.pdf

Spring can you autowire inside an abstract class?

In my case, inside a Spring4 Application, i had to use a classic Abstract Factory Pattern(for which i took the idea from - http://java-design-patterns.com/patterns/abstract-factory/) to create instances each and every time there was a operation to be done.So my code was to be designed like:

public abstract class EO {
    @Autowired
    protected SmsNotificationService smsNotificationService;
    @Autowired
    protected SendEmailService sendEmailService;
    ...
    protected abstract void executeOperation(GenericMessage gMessage);
}

public final class OperationsExecutor {
    public enum OperationsType {
        ENROLL, CAMPAIGN
    }

    private OperationsExecutor() {
    }

    public static Object delegateOperation(OperationsType type, Object obj) 
    {
        switch(type) {
            case ENROLL:
                if (obj == null) {
                    return new EnrollOperation();
                }
                return EnrollOperation.validateRequestParams(obj);
            case CAMPAIGN:
                if (obj == null) {
                    return new CampaignOperation();
                }
                return CampaignOperation.validateRequestParams(obj);
            default:
                throw new IllegalArgumentException("OperationsType not supported.");
        }
    }
}

@Configurable(dependencyCheck = true)
public class CampaignOperation extends EO {
    @Override
    public void executeOperation(GenericMessage genericMessage) {
        LOGGER.info("This is CAMPAIGN Operation: " + genericMessage);
    }
}

Initially to inject the dependencies in the abstract class I tried all stereotype annotations like @Component, @Service etc but even though Spring context file had ComponentScanning for the entire package, but somehow while creating instances of Subclasses like CampaignOperation, the Super Abstract class EO was having null for its properties as spring was unable to recognize and inject its dependencies.After much trial and error I used this **@Configurable(dependencyCheck = true)** annotation and finally Spring was able to inject the dependencies and I was able to use the properties in the subclass without cluttering them with too many properties.

<context:annotation-config />
<context:component-scan base-package="com.xyz" />

I also tried these other references to find a solution:

  1. http://www.captaindebug.com/2011/06/implementing-springs-factorybean.html#.WqF5pJPwaAN
  2. http://forum.spring.io/forum/spring-projects/container/46815-problem-with-autowired-in-abstract-class
  3. https://github.com/cavallefano/Abstract-Factory-Pattern-Spring-Annotation
  4. http://www.jcombat.com/spring/factory-implementation-using-servicelocatorfactorybean-in-spring
  5. https://www.madbit.org/blog/programming/1074/1074/#sthash.XEJXdIR5.dpbs
  6. Using abstract factory with Spring framework
  7. Spring Autowiring not working for Abstract classes
  8. Inject spring dependency in abstract super class
  9. Spring and Abstract class - injecting properties in abstract classes
    1. Spring autowire dependency defined in an abstract class

Please try using **@Configurable(dependencyCheck = true)** and update this post, I might try helping you if you face any problems.

Uploading a file in Rails

Update 2018

While everything written below still holds true, Rails 5.2 now includes active_storage, which allows stuff like uploading directly to S3 (or other cloud storage services), image transformations, etc. You should check out the rails guide and decide for yourself what fits your needs.


While there are plenty of gems that solve file uploading pretty nicely (see https://www.ruby-toolbox.com/categories/rails_file_uploads for a list), rails has built-in helpers which make it easy to roll your own solution.

Use the file_field-form helper in your form, and rails handles the uploading for you:

<%= form_for @person do |f| %>
  <%= f.file_field :picture %>
<% end %>

You will have access in the controller to the uploaded file as follows:

uploaded_io = params[:person][:picture]
File.open(Rails.root.join('public', 'uploads', uploaded_io.original_filename), 'wb') do |file|
  file.write(uploaded_io.read)
end

It depends on the complexity of what you want to achieve, but this is totally sufficient for easy file uploading/downloading tasks. This example is taken from the rails guides, you can go there for further information: http://guides.rubyonrails.org/form_helpers.html#uploading-files

R object identification

attributes(someObject) 

Can also be useful

How to execute a remote command over ssh with arguments?

This is an example that works on the AWS Cloud. The scenario is that some machine that booted from autoscaling needs to perform some action on another server, passing the newly spawned instance DNS via SSH

# Get the public DNS of the current machine (AWS specific)
MY_DNS=`curl -s http://169.254.169.254/latest/meta-data/public-hostname`


ssh \
    -o StrictHostKeyChecking=no \
    -i ~/.ssh/id_rsa \
    [email protected] \
<< EOF
cd ~/
echo "Hey I was just SSHed by ${MY_DNS}"
run_other_commands
# Newline is important before final EOF!

EOF

exception in thread 'main' java.lang.NoClassDefFoundError:

type the following in the cmd prompt, within your folder:

set classpath=%classpath%;.;

WPF - add static items to a combo box

Here is the code from MSDN and the link - Article Link, which you should check out for more detail.

<ComboBox Text="Is not open">
    <ComboBoxItem Name="cbi1">Item1</ComboBoxItem>
    <ComboBoxItem Name="cbi2">Item2</ComboBoxItem>
    <ComboBoxItem Name="cbi3">Item3</ComboBoxItem>
</ComboBox>

How do I get my page title to have an icon?

<link rel="shortcut icon" type="image/x-icon" href="favicon.ico" />

add this to your HTML Head. Of course the file "favicon.ico" has to exist. I think 16x16 or 32x32 pixel files are best.

How do I prevent Conda from activating the base environment by default?

I have conda 4.6 with a similar block of code that was added by conda. In my case, there's a conda configuration setting to disable the automatic base activation:

conda config --set auto_activate_base false

The first time you run it, it'll create a ./condarc in your home directory with that setting to override the default.

This wouldn't de-clutter your .bash_profile but it's a cleaner solution without manual editing that section that conda manages.

Passing multiple values for a single parameter in Reporting Services

It would probably be easier to add the multi values to a table first and then you can join or whatever you'd like (even with wildcards) or save the data to another table for later use (or even add the values to another table).

Set the Parameter value via expression in the dataset:

="SELECT DISTINCT * FROM (VALUES('" & JOIN(Parameters!SearchValue.Value, "'),('") & "')) 
AS tbl(Value)"

The query itself:

DECLARE @Table AS TABLE (Value nvarchar(max))

INSERT INTO @Table EXEC sp_executeSQL @SearchValue 

Wildcard example:

SELECT * FROM YOUR_TABLE yt 

INNER JOIN @Table rt ON yt.[Join_Value] LIKE '%' + rt.[Value] + '%'

I'd love to figure out a way to do it without dynamic SQL but I don't think it'll work due to the way SSRS passes the parameters to the actual query. If someone knows better, please let me know.

How can I print each command before executing?

set -o xtrace

or

bash -x myscript.sh

This works with standard /bin/sh as well IIRC (it might be a POSIX thing then)

And remember, there is bashdb (bash Shell Debugger, release 4.0-0.4)


To revert to normal, exit the subshell or

set +o xtrace

The result of a query cannot be enumerated more than once

if you getting this type of error so I suggest you used to stored proc data as usual list then binding the other controls because I also get this error so I solved it like this ex:-

repeater.DataSource = data.SPBinsReport().Tolist();
repeater.DataBind();

try like this

Best way to check if an PowerShell Object exist?

You can also do

if ($ie) {
    # Do Something if $ie is not null
}

Difference between logger.info and logger.debug

  1. INFO is used to log the information your program is working as expected.
  2. DEBUG is used to find the reason in case your program is not working as expected or an exception has occurred. it's in the interest of the developer.

Postgresql : Connection refused. Check that the hostname and port are correct and that the postmaster is accepting TCP/IP connections

The error you quote has nothing to do with pg_hba.conf; it's failing to connect, not failing to authorize the connection.

Do what the error message says:

Check that the hostname and port are correct and that the postmaster is accepting TCP/IP connections

You haven't shown the command that produces the error. Assuming you're connecting on localhost port 5432 (the defaults for a standard PostgreSQL install), then either:

  • PostgreSQL isn't running

  • PostgreSQL isn't listening for TCP/IP connections (listen_addresses in postgresql.conf)

  • PostgreSQL is only listening on IPv4 (0.0.0.0 or 127.0.0.1) and you're connecting on IPv6 (::1) or vice versa. This seems to be an issue on some older Mac OS X versions that have weird IPv6 socket behaviour, and on some older Windows versions.

  • PostgreSQL is listening on a different port to the one you're connecting on

  • (unlikely) there's an iptables rule blocking loopback connections

(If you are not connecting on localhost, it may also be a network firewall that's blocking TCP/IP connections, but I'm guessing you're using the defaults since you didn't say).

So ... check those:

  • ps -f -u postgres should list postgres processes

  • sudo lsof -n -u postgres |grep LISTEN or sudo netstat -ltnp | grep postgres should show the TCP/IP addresses and ports PostgreSQL is listening on

BTW, I think you must be on an old version. On my 9.3 install, the error is rather more detailed:

$ psql -h localhost -p 12345
psql: could not connect to server: Connection refused
        Is the server running on host "localhost" (::1) and accepting
        TCP/IP connections on port 12345?

Fixing the order of facets in ggplot

There are a couple of good solutions here.

Similar to the answer from Harpal, but within the facet, so doesn't require any change to underlying data or pre-plotting manipulation:

# Change this code:
facet_grid(.~size) + 
# To this code:
facet_grid(~factor(size, levels=c('50%','100%','150%','200%')))

This is flexible, and can be implemented for any variable as you change what element is faceted, no underlying change in the data required.

SQL Server: Make all UPPER case to Proper Case/Title Case

I know this is late post in this thread but, worth looking. This function works for me ever time. So thought of sharing it.

CREATE FUNCTION [dbo].[fnConvert_TitleCase] (@InputString VARCHAR(4000) )
RETURNS VARCHAR(4000)
AS
BEGIN
DECLARE @Index INT
DECLARE @Char CHAR(1)
DECLARE @OutputString VARCHAR(255)

SET @OutputString = LOWER(@InputString)
SET @Index = 2
SET @OutputString = STUFF(@OutputString, 1, 1,UPPER(SUBSTRING(@InputString,1,1)))

WHILE @Index <= LEN(@InputString)
BEGIN
    SET @Char = SUBSTRING(@InputString, @Index, 1)
    IF @Char IN (' ', ';', ':', '!', '?', ',', '.', '_', '-', '/', '&','''','(')
    IF @Index + 1 <= LEN(@InputString)
BEGIN
    IF @Char != ''''
    OR
    UPPER(SUBSTRING(@InputString, @Index + 1, 1)) != 'S'
    SET @OutputString =
    STUFF(@OutputString, @Index + 1, 1,UPPER(SUBSTRING(@InputString, @Index + 1, 1)))
END
    SET @Index = @Index + 1
END

RETURN ISNULL(@OutputString,'')
END

Test calls:

select dbo.fnConvert_TitleCase(Upper('ÄÄ ÖÖ ÜÜ ÉÉ ØØ CC ÆÆ')) as test
select dbo.fnConvert_TitleCase(upper('Whatever the mind of man can conceive and believe, it can achieve. – Napoleon hill')) as test

Results:

enter image description here

Upgrade Node.js to the latest version on Mac OS

Easy nad Safe Steps

Step 1: Install NVM

brew install nvm

Step 2: Create a directory for NVM

mkdir ~/.nvm/

Step 3: Configure your environmental variables

nano ~/.bash_profile

PASTE BELOW CODE

export NVM_DIR=~/.nvm
source $(brew --prefix nvm)/nvm.sh

source ~/.bash_profile

Step 4: Double check your work

nvm ls

Step 5: Install Node

nvm install 9.x.x

Step6: Upgrade

nvm ls-remote

   v10.16.2   (LTS: Dubnium)
   v10.16.3   (Latest LTS: Dubnium) ..........

nvm install v10.16.3

Troubleshooting

Error Example #1
rm -rf /usr/local/lib/node_modules
brew uninstall node
brew install node --without-npm
echo prefix=~/.npm-packages >> ~/.npmrc
curl -L https://www.npmjs.com/install.sh | sh

https://www.chrisjmendez.com/2018/02/07/install/

xcopy file, rename, suppress "Does xxx specify a file name..." message

For duplicating large files, xopy with /J switch is a good choice. In this case, simply pipe an F for file or a D for directory. Also, you can save jobs in an array for future references. For example:

$MyScriptBlock = {
    Param ($SOURCE, $DESTINATION) 
    'F' | XCOPY $SOURCE $DESTINATION /J/Y 
    #DESTINATION IS FILE, COPY WITHOUT PROMPT IN DIRECT BUFFER MODE
}
JOBS +=START-JOB -SCRIPTBLOCK $MyScriptBlock -ARGUMENTLIST $SOURCE,$DESTIBNATION
$JOBS | WAIT-JOB | REMOVE-JOB

Thanks to Chand with a bit modifications: https://stackoverflow.com/users/3705330/chand

node.js http 'get' request with query string parameters

No need for a 3rd party library. Use the nodejs url module to build a URL with query parameters:

const requestUrl = url.parse(url.format({
    protocol: 'https',
    hostname: 'yoursite.com',
    pathname: '/the/path',
    query: {
        key: value
    }
}));

Then make the request with the formatted url. requestUrl.path will include the query parameters.

const req = https.get({
    hostname: requestUrl.hostname,
    path: requestUrl.path,
}, (res) => {
   // ...
})

MySQL Alter Table Add Field Before or After a field already present

$query = "ALTER TABLE `" . $table_prefix . "posts_to_bookmark` 
          ADD COLUMN `ping_status` INT(1) NOT NULL 
          AFTER `<TABLE COLUMN BEFORE THIS COLUMN>`";

I believe you need to have ADD COLUMN and use AFTER, not BEFORE.

In case you want to place column at the beginning of a table, use the FIRST statement:

$query = "ALTER TABLE `" . $table_prefix . "posts_to_bookmark`
          ADD COLUMN `ping_status` INT(1) NOT NULL 
          FIRST";

http://dev.mysql.com/doc/refman/5.1/en/alter-table.html

Generating a unique machine id

With our licensing tool we consider the following components

  • MAC Address
  • CPU (Not the serial number, but the actual CPU profile like stepping and model)
  • System Drive Serial Number (Not Volume Label)
  • Memory
  • CD-ROM model & vendor
  • Video Card model & vendor
  • IDE Controller
  • SCSI Controller

However, rather than just hashing the components and creating a pass/fail system, we create a comparable fingerprint that can be used to determine how different two machine profiles are. If the difference rating is above a specified tolerance then ask the user to activate again.

We've found over the last 8 years in use with hundreds of thousands of end-user installs that this combination works well to provide a reliably unique machine id - even for virtual machines and cloned OS installs.

How to identify and switch to the frame in selenium webdriver when frame does not have id

you can use cssSelector,

driver.switchTo().frame(driver.findElement(By.cssSelector("iframe[title='Fill Quote']")));

'printf' with leading zeros in C

Your format specifier is incorrect. From the printf() man page on my machine:

0 A zero '0' character indicating that zero-padding should be used rather than blank-padding. A '-' overrides a '0' if both are used;

Field Width: An optional digit string specifying a field width; if the output string has fewer characters than the field width it will be blank-padded on the left (or right, if the left-adjustment indicator has been given) to make up the field width (note that a leading zero is a flag, but an embedded zero is part of a field width);

Precision: An optional period, '.', followed by an optional digit string giving a precision which specifies the number of digits to appear after the decimal point, for e and f formats, or the maximum number of characters to be printed from a string; if the digit string is missing, the precision is treated as zero;

For your case, your format would be %09.3f:

#include <stdio.h>

int main(int argc, char **argv)
{
  printf("%09.3f\n", 4917.24);
  return 0;
}

Output:

$ make testapp
cc     testapp.c   -o testapp
$ ./testapp 
04917.240

Note that this answer is conditional on your embedded system having a printf() implementation that is standard-compliant for these details - many embedded environments do not have such an implementation.

How to enable remote access of mysql in centos?

In case of Allow IP to mysql server linux machine. you can do following command--

 nano /etc/httpd/conf.d/phpMyAdmin.conf  and add Desired IP.

<Directory /usr/share/phpMyAdmin/>
   AddDefaultCharset UTF-8
   Order allow,deny
   allow from all
   <IfModule mod_authz_core.c>
     # Apache 2.4
     <RequireAny>

    Require ip 192.168.9.1(Desired IP)

</RequireAny>
   </IfModule>
 <IfModule !mod_authz_core.c>
     # Apache 2.2
     Order Deny,Allow
     #Allow from All

     Allow from 192.168.9.1(Desired IP)

</IfModule>

And after Update, please restart using following command--

sudo systemctl restart httpd.service

How to Edit a row in the datatable

Try this I am also not 100 % sure

        for( int i = 0 ;i< dt.Rows.Count; i++)
        {
           If(dt.Rows[i].Product_id == 2)
           {
              dt.Rows[i].Columns["Product_name"].ColumnName = "cde";
           }
        }

How do I read text from the clipboard?

The python standard library does it...

try:
    # Python3
    import tkinter as tk
except ImportError:
    # Python2
    import Tkinter as tk

def getClipboardText():
    root = tk.Tk()
    # keep the window from showing
    root.withdraw()
    return root.clipboard_get()

Sending a mail from a linux shell script

SEND MAIL FROM LINUX TO GMAIL

USING POSTFIX

1: install software

Debian and Ubuntu:

apt-get update && apt-get install postfix mailutils

OpenSUSE:

zypper update && zypper install postfix mailx cyrus-sasl

Fedora:

dnf update && dnf install postfix mailx

CentOS:

yum update && yum install postfix mailx cyrus-sasl cyrus-sasl-plain

Arch Linux:

pacman -Sy postfix mailutils

FreeBSD:

portsnap fetch extract update

cd /usr/ports/mail/postfix

make config

in configaration select SASL support

make install clean

pkg install mailx

2. Configure Gmail

/etc/postfix. Create or edit the password file:

vim /etc/postfix/sasl_passwd

i m using vim u can use any file editer like nano, cat .....

>Ubuntu, Fedora, CentOS,Debian, OpenSUSE, Arch Linux:

add this

where user replace with your mailname and password is your gmail password

[smtp.gmail.com]:587    [email protected]:password

Save and close the file and Make it accessible only by root: becouse its an sensitive content which contains ur password

chmod 600 /usr/local/etc/postfix/sasl_passwd

>FreeBSD:

directory /usr/local/etc/postfix.

vim /usr/local/etc/postfix/sasl_passwd

Add the line:

[smtp.gmail.com]:587    [email protected]:password

Save and Make it accessible only by root:

chmod 600 /usr/local/etc/postfix/sasl_passwd

3. Postfix configuration

configuration file main.cf

6 parameters we must set in the Postfix

Ubuntu, Arch Linux,Debian:

edit

 vim /etc/postfix/main.cf

modify the following values:

relayhost = [smtp.gmail.com]:587
smtp_use_tls = yes
smtp_sasl_auth_enable = yes
smtp_sasl_security_options =
smtp_sasl_password_maps = hash:/etc/postfix/sasl_passwd
smtp_tls_CAfile = /etc/ssl/certs/ca-certificates.crt

smtp_sasl_security_options which in configuration will be set to empty, to ensure that no Gmail-incompatible security options are used.

save and close

as like for

OpenSUSE:

vim /etc/postfix/main.cf

modify

relayhost = [smtp.gmail.com]:587
smtp_use_tls = yes
smtp_sasl_auth_enable = yes
smtp_sasl_security_options =
smtp_sasl_password_maps = hash:/etc/postfix/sasl_passwd
smtp_tls_CAfile = /etc/ssl/ca-bundle.pem

it also requires configuration of file master.cf

modify:

vim /etc/postfix/master.cf

as by uncommenting this line(remove #)

#tlsmgr unix - - n 1000? 1 tlsmg

save and close

Fedora, CentOS:

vim /etc/postfix/main.cf

modify

relayhost = [smtp.gmail.com]:587
smtp_use_tls = yes
smtp_sasl_auth_enable = yes
smtp_sasl_security_options =
smtp_sasl_password_maps = hash:/etc/postfix/sasl_passwd
smtp_tls_CAfile = /etc/ssl/certs/ca-bundle.crt

FreeBSD:

vim /usr/local/etc/postfix/main.cf

modify:

relayhost = [smtp.gmail.com]:587
smtp_use_tls = yes
smtp_sasl_auth_enable = yes
smtp_sasl_security_options =
smtp_sasl_password_maps = hash:/usr/local/etc/postfix/sasl_passwd
smtp_tls_CAfile = /etc/mail/certs/cacert.pem

save and close this

4. Process Password File:

Ubuntu, Fedora, CentOS, OpenSUSE, Arch Linux,Debian:

postmap /etc/postfix/sasl_passwd

for freeBSD

postmap /usr/local/etc/postfix/sasl_passwd

4.1) Restart postfix

Ubuntu, Fedora, CentOS, OpenSUSE, Arch Linux,Debian:

systemctl restart postfix.service

for FreeBSD:

service postfix onestart
nano /etc/rc.conf

add

postfix_enable=YES

save then run to start

service postfix start

5. Enable "Less Secure Apps" In Gmail using help of below link

https://support.google.com/accounts/answer/6010255

6. Send A Test Email

mail -s "subject" [email protected]

press enter

add body of mail as your wish press enter then press ctrl+d for proper termination

if it not working check the all steps again and check if u enable "less secure app" in your gmail

then restart postfix if u modify anything in that

for shell script create the .sh file and add 6 step command as your requirement

for example just for a sample

#!/bin/bash
REALVALUE=$(df / | grep / | awk '{ print $5}' | sed 's/%//g')
THRESHOLD=80

if [ "$REALVALUE" -gt "$THRESHOLD" ] ; then
    mail -s 'Disk Space Alert' [email protected] << EOF
Your root partition remaining free space is critically low. Used: $REALVALUE%
EOF
fi

The script sends an email when the disk usage rises above the percentage specified by the THRESHOLD varialbe (80% here).

TypeError: 'tuple' object does not support item assignment when swapping values

Evaluating "1,2,3" results in (1, 2, 3), a tuple. As you've discovered, tuples are immutable. Convert to a list before processing.

Optional args in MATLAB functions

A simple way of doing this is via nargin (N arguments in). The downside is you have to make sure that your argument list and the nargin checks match.

It is worth remembering that all inputs are optional, but the functions will exit with an error if it calls a variable which is not set. The following example sets defaults for b and c. Will exit if a is not present.

function [ output_args ] = input_example( a, b, c )
if nargin < 1
  error('input_example :  a is a required input')
end

if nargin < 2
  b = 20
end

if nargin < 3
  c = 30
end
end

How to add and get Header values in WebApi

try these line of codes working in my case:

IEnumerable<string> values = new List<string>();
this.Request.Headers.TryGetValues("Authorization", out values);

Nginx reverse proxy causing 504 Gateway Timeout

Increasing the timeout will not likely solve your issue since, as you say, the actual target web server is responding just fine.

I had this same issue and I found it had to do with not using a keep-alive on the connection. I can't actually answer why this is but, in clearing the connection header I solved this issue and the request was proxied just fine:

server {
    location / {
        proxy_set_header   X-Real-IP $remote_addr;
        proxy_set_header   Host      $http_host;
        proxy_http_version 1.1;
        proxy_set_header Connection "";
        proxy_pass http://localhost:5000;
    }
}

Have a look at this posts which explains it in more detail: nginx close upstream connection after request Keep-alive header clarification http://nginx.org/en/docs/http/ngx_http_upstream_module.html#keepalive

Why XML-Serializable class need a parameterless constructor

First of all, this what is written in documentation. I think it is one of your class fields, not the main one - and how you want deserialiser to construct it back w/o parameterless construction ?

I think there is a workaround to make constructor private.

Powershell Error "The term 'Get-SPWeb' is not recognized as the name of a cmdlet, function..."

I think this need to be run from the Management Shell rather than the console, it sounds like the module isn't being imported into the Powershell console. You can add the module by running:

Add-PSSnapin Microsoft.Sharepoint.Powershell

in the Powershell console.

Bootstrap 3.0 - Fluid Grid that includes Fixed Column Sizes

OK, my answer is super nice:

<style>
    #wrapper {
        display:flex;    
        width:100%;
        align-content: streach;
        justify-content: space-between;
    }    

    #wrapper div {
        height:100px;
    }

    .static240 {
        flex: 0 0 240px;
    }
    .static160 {
        flex: 0 0 160px;
    }

    .growMax {
        flex-grow: 1;
    }

</style>

<div id="wrapper">
  <div class="static240" style="background:red;" > </div>
  <div class="static160"  style="background: green;" > </div> 
  <div class="growMax"  style="background:yellow;"  ></div>
</div>

jsfiddle playground

if you wanna support for all browser, use https://github.com/10up/flexibility

How to check if an element exists in the xml using xpath?

Use the boolean() XPath function

The boolean function converts its argument to a boolean as follows:

  • a number is true if and only if it is neither positive or negative zero nor NaN

  • a node-set is true if and only if it is non-empty

  • a string is true if and only if its length is non-zero

  • an object of a type other than the four basic types is converted to a boolean in a way that is dependent on that type

If there is an AttachedXml in the CreditReport of primary Consumer, then it will return true().

boolean(/mc:Consumers
          /mc:Consumer[@subjectIdentifier='Primary']
            //mc:CreditReport/mc:AttachedXml)

Force drop mysql bypassing foreign key constraint

Since you are not interested in keeping any data, drop the entire database and create a new one.

What is the default database path for MongoDB?

I depends on the version and the distro.

For example the default download pre-2.2 from the MongoDB site uses: /data/db but the Ubuntu install at one point used to use: var/lib/mongodb.

I think these have been standardised now so that 2.2+ will only use data/db whether it comes from direct download on the site or from the repos.

How to set margin with jquery?

try

el.css('margin-left',mrg+'px');

TSQL: How to convert local time to UTC? (SQL Server 2008)

7 years passed and...
actually there's this new SQL Server 2016 feature that does exactly what you need.
It is called AT TIME ZONE and it converts date to a specified time zone considering DST (daylight saving time) changes.
More info here: https://msdn.microsoft.com/en-us/library/mt612795.aspx

VB.net: Date without time

Either use one of the standard date and time format strings which only specifies the date (e.g. "D" or "d"), or a custom date and time format string which only uses the date parts (e.g. "yyyy/MM/dd").

How to get the current time in Google spreadsheet using script editor?

I considered with timezone in my Google Docs like this:

timezone = "GMT+" + new Date().getTimezoneOffset()/60
var date = Utilities.formatDate(new Date(), timezone, "yyyy-MM-dd HH:mm"); // "yyyy-MM-dd'T'HH:mm:ss'Z'"

my script for Google docs

Read .mat files in Python

There is also the MATLAB Engine for Python by MathWorks itself. If you have MATLAB, this might be worth considering (I haven't tried it myself but it has a lot more functionality than just reading MATLAB files). However, I don't know if it is allowed to distribute it to other users (it is probably not a problem if those persons have MATLAB. Otherwise, maybe NumPy is the right way to go?).

Also, if you want to do all the basics yourself, MathWorks provides (if the link changes, try to google for matfile_format.pdf or its title MAT-FILE Format) a detailed documentation on the structure of the file format. It's not as complicated as I personally thought, but obviously, this is not the easiest way to go. It also depends on how many features of the .mat-files you want to support.

I've written a "small" (about 700 lines) Python script which can read some basic .mat-files. I'm neither a Python expert nor a beginner and it took me about two days to write it (using the MathWorks documentation linked above). I've learned a lot of new stuff and it was quite fun (most of the time). As I've written the Python script at work, I'm afraid I cannot publish it... But I can give some advice here:

  • First read the documentation.
  • Use a hex editor (such as HxD) and look into a reference .mat-file you want to parse.
  • Try to figure out the meaning of each byte by saving the bytes to a .txt file and annotate each line.
  • Use classes to save each data element (such as miCOMPRESSED, miMATRIX, mxDOUBLE, or miINT32)
  • The .mat-files' structure is optimal for saving the data elements in a tree data structure; each node has one class and subnodes

The apk must be signed with the same certificates as the previous version

I just had this occur out of the clear blue. I really do not think I changed anything.

However, Build => Clean Project fixed it.

Using an HTTP PROXY - Python

Python 3:

import urllib.request

htmlsource = urllib.request.FancyURLopener({"http":"http://127.0.0.1:8080"}).open(url).read().decode("utf-8")

WCF ServiceHost access rights

Other option that work is ..,

If you change de indentity in application pool, you can run the code, the idea is change the aplication pool execution account for one account with more privileges,

For more details use this blog

https://letrasandnumeros.com/2017/11/27/http-could-not-register-url-http-80-hellowcf-your-process-does-not-have-access-rights-to-this-namespace/

Concatenating strings in Razor

the plus works just fine, i personally prefer using the concat function.

var s = string.Concat(string 1, string 2, string, 3, etc)

How to take a screenshot programmatically on iOS

This will work with swift 4.2, the screenshot will be saved in library, but please don't forget to edit the info.plist @ NSPhotoLibraryAddUsageDescription :

  @IBAction func takeScreenshot(_ sender: UIButton) {

    //Start full Screenshot
    print("full Screenshot")
    UIGraphicsBeginImageContext(card.frame.size)
    view.layer.render(in: UIGraphicsGetCurrentContext()!)
    var sourceImage = UIGraphicsGetImageFromCurrentImageContext()
    UIGraphicsEndImageContext()
    UIImageWriteToSavedPhotosAlbum(sourceImage!, nil, nil, nil)

    //Start partial Screenshot
    print("partial Screenshot")
    UIGraphicsBeginImageContext(card.frame.size)
    sourceImage?.draw(at: CGPoint(x:-25,y:-100)) //the screenshot starts at -25, -100
    var croppedImage = UIGraphicsGetImageFromCurrentImageContext()
    UIGraphicsEndImageContext()
    UIImageWriteToSavedPhotosAlbum(croppedImage!, nil, nil, nil)

}

Transpose a data frame

df.aree <- as.data.frame(t(df.aree))
colnames(df.aree) <- df.aree[1, ]
df.aree <- df.aree[-1, ]
df.aree$myfactor <- factor(row.names(df.aree))

How to disable textbox from editing?

        textBox1.Enabled = false;

"false" property will make the text box disable. and "true" will make it in regular form. Thanks.

Java: String - add character n-times

You can use Guava's Strings.repeat method:

String existingString = ...
existingString += Strings.repeat("foo", n);

How can I add C++11 support to Code::Blocks compiler?

A simple way is to write:

-std=c++11

in the Other Options section of the compiler flags. You could do this on a per-project basis (Project -> Build Options), and/or set it as a default option in the Settings -> Compilers part.

Some projects may require -std=gnu++11 which is like C++11 but has some GNU extensions enabled.

If using g++ 4.9, you can use -std=c++14 or -std=gnu++14.

How do you pull first 100 characters of a string in PHP

try this function

function summary($str, $limit=100, $strip = false) {
    $str = ($strip == true)?strip_tags($str):$str;
    if (strlen ($str) > $limit) {
        $str = substr ($str, 0, $limit - 3);
        return (substr ($str, 0, strrpos ($str, ' ')).'...');
    }
    return trim($str);
}

Is there a way to ignore a single FindBugs warning?

I'm going to leave this one here: https://stackoverflow.com/a/14509697/1356953

Please note that this works with java.lang.SuppressWarningsso no need to use a separate annotation.

@SuppressWarnings on a field only suppresses findbugs warnings reported for that field declaration, not every warning associated with that field.

For example, this suppresses the "Field only ever set to null" warning:

@SuppressWarnings("UWF_NULL_FIELD") String s = null; I think the best you can do is isolate the code with the warning into the smallest method you can, then suppress the warning on the whole method.

Convert string to datetime

By using Date.parse() you get the unix timestamp.

date = new Date( Date.parse("05/01/2020") )
//Fri May 01 2020 00:00:00 GMT

MySQL maximum memory usage

If you are looking for optimizing your docker mysql container then the below command may help. I was able to run mysql docker container from a default 480mb to mere 100 mbs

docker run -d -p 3306:3306 -e MYSQL_DATABASE=test -e MYSQL_ROOT_PASSWORD=tooor -e MYSQL_USER=test -e MYSQL_PASSWORD=test -v /mysql:/var/lib/mysql --name mysqldb mysql --table_definition_cache=100 --performance_schema=0 --default-authentication-plugin=mysql_native_password

Permissions for /var/www/html

You just need 775 for /var/www/html as long as you are logging in as myuser. The 7 octal in the middle (which is for "group" acl) ensures that the group has permission to read/write/execute. As long as you belong to the group that owns the files, "myuser" should be able to write to them. You may need to give group permissions to all the files in the docuemnt root, though:

chmod -R g+w /var/www/html

Python sockets error TypeError: a bytes-like object is required, not 'str' with send function

The reason for this error is that in Python 3, strings are Unicode, but when transmitting on the network, the data needs to be bytes instead. So... a couple of suggestions:

  1. Suggest using c.sendall() instead of c.send() to prevent possible issues where you may not have sent the entire msg with one call (see docs).
  2. For literals, add a 'b' for bytes string: c.sendall(b'Thank you for connecting')
  3. For variables, you need to encode Unicode strings to byte strings (see below)

Best solution (should work w/both 2.x & 3.x):

output = 'Thank you for connecting'
c.sendall(output.encode('utf-8'))

Epilogue/background: this isn't an issue in Python 2 because strings are bytes strings already -- your OP code would work perfectly in that environment. Unicode strings were added to Python in releases 1.6 & 2.0 but took a back seat until 3.0 when they became the default string type. Also see this similar question as well as this one.

BEGIN - END block atomic transactions in PL/SQL

The default behavior of Commit PL/SQL block:

You should explicitly commit or roll back every transaction. Whether you issue the commit or rollback in your PL/SQL program or from a client program depends on the application logic. If you do not commit or roll back a transaction explicitly, the client environment determines its final state.

For example, in the SQLPlus environment, if your PL/SQL block does not include a COMMIT or ROLLBACK statement, the final state of your transaction depends on what you do after running the block. If you execute a data definition, data control, or COMMIT statement or if you issue the EXIT, DISCONNECT, or QUIT command, Oracle commits the transaction. If you execute a ROLLBACK statement or abort the SQLPlus session, Oracle rolls back the transaction.

https://docs.oracle.com/cd/B19306_01/appdev.102/b14261/sqloperations.htm#i7105

What does ON [PRIMARY] mean?

To add a very important note on what Mark S. has mentioned in his post. In the specific SQL Script that has been mentioned in the question you can NEVER mention two different file groups for storing your data rows and the index data structure.

The reason why is due to the fact that the index being created in this case is a clustered Index on your primary key column. The clustered index data and the data rows of your table can NEVER be on different file groups.

So in case you have two file groups on your database e.g. PRIMARY and SECONDARY then below mentioned script will store your row data and clustered index data both on PRIMARY file group itself even though I've mentioned a different file group ([SECONDARY]) for the table data. More interestingly the script runs successfully as well (when I was expecting it to give an error as I had given two different file groups :P). SQL Server does the trick behind the scene silently and smartly.

CREATE TABLE [dbo].[be_Categories](
    [CategoryID] [uniqueidentifier] ROWGUIDCOL  NOT NULL CONSTRAINT [DF_be_Categories_CategoryID]  DEFAULT (newid()),
    [CategoryName] [nvarchar](50) NULL,
    [Description] [nvarchar](200) NULL,
    [ParentID] [uniqueidentifier] NULL,
 CONSTRAINT [PK_be_Categories] PRIMARY KEY CLUSTERED 
(
    [CategoryID] ASC
)WITH (PAD_INDEX  = OFF, STATISTICS_NORECOMPUTE  = OFF, IGNORE_DUP_KEY = OFF, ALLOW_ROW_LOCKS  = ON, ALLOW_PAGE_LOCKS  = ON) ON [PRIMARY]
) ON [SECONDARY]
GO

NOTE: Your index can reside on a different file group ONLY if the index being created is non-clustered in nature.

The below script which creates a non-clustered index will get created on [SECONDARY] file group instead when the table data already resides on [PRIMARY] file group:

CREATE NONCLUSTERED INDEX [IX_Categories] ON [dbo].[be_Categories]
(
    [CategoryName] ASC
)WITH (PAD_INDEX = OFF, STATISTICS_NORECOMPUTE = OFF, SORT_IN_TEMPDB = OFF, DROP_EXISTING = OFF, ONLINE = OFF, ALLOW_ROW_LOCKS = ON, ALLOW_PAGE_LOCKS = ON) ON [Secondary]
GO

You can get more information on how storing non-clustered indexes on a different file group can help your queries perform better. Here is one such link.

How to make 'submit' button disabled?

As seen in this Angular example, there is a way to disable a button until the whole form is valid:

<button type="submit" [disabled]="!ngForm.valid">Submit</button>

How to make matrices in Python?

you can also use append function

b = [ ]

for x in range(0, 5):
    b.append(["O"] * 5)

def print_b(b):
    for row in b:
        print " ".join(row)

How to set a dropdownlist item as selected in ASP.NET?

Set dropdown property

selected="true"

Missing `server' JVM (Java\jre7\bin\server\jvm.dll.)

To Fix The "Missing "server" JVM at C:\Program Files\Java\jre7\bin\server\jvm­­.dll, please install or use the JRE or JDK that contains these missing components.

Follow these steps:

Go to oracle.com and install Java JRE7 (Check if Java 6 is not installed already)

After that, go to C:/Program files/java/jre7/bin

Here, create an folder called Server

Now go into the C:/Program files/java/jre7/bin/client folder

Copy all the data in this folder into the new C:/Program files/java/jre7/bin/Server folder

GCC fatal error: stdio.h: No such file or directory

I had the same problem. I installed "XCode: development tools" from the app store and it fixed the problem for me.

I think this link will help: https://itunes.apple.com/us/app/xcode/id497799835?mt=12&ls=1

Credit to Yann Ramin for his advice. I think there is a better solution with links, but this was easy and fast.

Good luck!

Xcode 10: A valid provisioning profile for this executable was not found

I had the case where my app would deploy to my iPhone but not my watch. Deploying to the watch would give the "A valid provisioning profile for this executable was not found." error. This is with XCode Version 11.2.1 and using the free developer account.

Here is what I did to get it deployed to my watch:

1) I deleted my provisioning profile in XCode. I did this by going to Window -> Devices And Simulators. Then right Click on the iPhone name and choose "Show Provisioning Profiles". From there I could delete the file

2) In The Devices and Simulators screen I also deleted my app from the "Installed Apps" section.

3) Did a "clean build folder" (Product -> Clean Build Folder)

4) In the "Build Settings" -> "Signing section" I made sure each target (iPhone, Tests and Watch) had the same settings (development team, code signing style, provisioning profile was set to automatic etc).

build settings details

5) Ensured the ~/Library/MobileDevice/Provisioning Profiles directory was empty.

6) Unplugged phone from computer

7) Rebooted computer, phone and watch

8) Plugged phone back into computer, and went through the "trust this machine" prompts on phone and watch.

9) Ran app. It worked!

Convert datatable to JSON in C#

We can accomplish the task in two simple way one is using Json.NET dll and another is by using StringBuilder class.

Using Newtonsoft Json.NET

string JSONresult;
JSONresult = JsonConvert.SerializeObject(dt);  
Response.Write(JSONresult);

Reference Link: Newtonsoft: Convert DataTable to JSON object in ASP.Net C#

Using StringBuilder

public string DataTableToJsonObj(DataTable dt)
{
    DataSet ds = new DataSet();
    ds.Merge(dt);
    StringBuilder JsonString = new StringBuilder();
    if (ds != null && ds.Tables[0].Rows.Count > 0)
    {
        JsonString.Append("[");
        for (int i = 0; i < ds.Tables[0].Rows.Count; i++)
        {
            JsonString.Append("{");
            for (int j = 0; j < ds.Tables[0].Columns.Count; j++)
            {
                if (j < ds.Tables[0].Columns.Count - 1)
                {
                    JsonString.Append("\"" + ds.Tables[0].Columns[j].ColumnName.ToString() + "\":" + "\"" + ds.Tables[0].Rows[i][j].ToString() + "\",");
                }
                else if (j == ds.Tables[0].Columns.Count - 1)
                {
                    JsonString.Append("\"" + ds.Tables[0].Columns[j].ColumnName.ToString() + "\":" + "\"" + ds.Tables[0].Rows[i][j].ToString() + "\"");
                }
            }
            if (i == ds.Tables[0].Rows.Count - 1)
            {
                JsonString.Append("}");
            }
            else
            {
                JsonString.Append("},");
            }
        }
        JsonString.Append("]");
        return JsonString.ToString();
    }
    else
    {
        return null;
    }
}

Reading all files in a directory, store them in objects, and send the object

Are you a lazy person like me and love npm module :D then check this out.

npm install node-dir

example for reading files:

var dir = require('node-dir');

dir.readFiles(__dirname,
    function(err, content, next) {
        if (err) throw err;
        console.log('content:', content);  // get content of files
        next();
    },
    function(err, files){
        if (err) throw err;
        console.log('finished reading files:', files); // get filepath 
   });    

Regex Last occurrence?

I used below regex to get that result also when its finished by a \

(\\[^\\]+)\\?$

[Regex Demo]

Declare an array in TypeScript

Few ways of declaring a typed array in TypeScript are

const booleans: Array<boolean> = new Array<boolean>();
// OR, JS like type and initialization
const booleans: boolean[] = [];

// or, if you have values to initialize 
const booleans: Array<boolean> = [true, false, true];
// get a vaue from that array normally
const valFalse = booleans[1];

How to insert values in table with foreign key using MySQL?

Case 1: Insert Row and Query Foreign Key

Here is an alternate syntax I use:

INSERT INTO tab_student 
   SET name_student = 'Bobby Tables',
       id_teacher_fk = (
       SELECT id_teacher
         FROM tab_teacher
        WHERE name_teacher = 'Dr. Smith')

I'm doing this in Excel to import a pivot table to a dimension table and a fact table in SQL so you can import to both department and expenses tables from the following:

enter image description here

Case 2: Insert Row and Then Insert Dependant Row

Luckily, MySQL supports LAST_INSERT_ID() exactly for this purpose.

INSERT INTO tab_teacher
   SET name_teacher = 'Dr. Smith';
INSERT INTO tab_student 
   SET name_student = 'Bobby Tables',
       id_teacher_fk = LAST_INSERT_ID()

How to set level logging to DEBUG in Tomcat?

JULI logging levels for Tomcat

SEVERE - Serious failures

WARNING - Potential problems

INFO - Informational messages

CONFIG - Static configuration messages

FINE - Trace messages

FINER - Detailed trace messages

FINEST - Highly detailed trace messages

You can find here more https://documentation.progress.com/output/ua/OpenEdge_latest/index.html#page/pasoe-admin/tomcat-logging.html

What is an unsigned char?

In terms of direct values a regular char is used when the values are known to be between CHAR_MIN and CHAR_MAX while an unsigned char provides double the range on the positive end. For example, if CHAR_BIT is 8, the range of regular char is only guaranteed to be [0, 127] (because it can be signed or unsigned) while unsigned char will be [0, 255] and signed char will be [-127, 127].

In terms of what it's used for, the standards allow objects of POD (plain old data) to be directly converted to an array of unsigned char. This allows you to examine the representation and bit patterns of the object. The same guarantee of safe type punning doesn't exist for char or signed char.

Declare a variable in DB2 SQL

I imagine this forum posting, which I quote fully below, should answer the question.


Inside a procedure, function, or trigger definition, or in a dynamic SQL statement (embedded in a host program):

BEGIN ATOMIC
 DECLARE example VARCHAR(15) ;
 SET example = 'welcome' ;
 SELECT *
 FROM   tablename
 WHERE  column1 = example ;
END

or (in any environment):

WITH t(example) AS (VALUES('welcome'))
SELECT *
FROM   tablename, t
WHERE  column1 = example

or (although this is probably not what you want, since the variable needs to be created just once, but can be used thereafter by everybody although its content will be private on a per-user basis):

CREATE VARIABLE example VARCHAR(15) ;
SET example = 'welcome' ;
SELECT *
FROM   tablename
WHERE  column1 = example ;

Programmatically scroll to a specific position in an Android ListView

You need two things to precisely define the scroll position of a listView:

To get the current listView Scroll position:

int firstVisiblePosition = listView.getFirstVisiblePosition(); 
int topEdge=listView.getChildAt(0).getTop(); //This gives how much the top view has been scrolled.

To set the listView Scroll position:

listView.setSelectionFromTop(firstVisiblePosition,0);
// Note the '-' sign for scrollTo.. 
listView.scrollTo(0,-topEdge);

Sort JavaScript object by key

Suppose it could be useful in VisualStudio debugger which shows unordered object properties.

(function(s) {
    var t = {};

    Object.keys(s).sort().forEach(function(k) {
        t[k] = s[k]
    });

    return t
})({
    b: 2,
    a: 1,
    c: 3
});

How can I get browser to prompt to save password?

Using a button to login:

If you use a type="button" with an onclick handler to login using ajax, then the browser won't offer to save the password.

<form id="loginform">
 <input name="username" type="text" />
 <input name="password" type="password" />
 <input name="doLogin"  type="button" value="Login" onclick="login(this.form);" />
</form>

Since this form does not have a submit button and has no action field, the browser will not offer to save the password.


Using a submit button to login:

However, if you change the button to type="submit" and handle the submit, then the browser will offer to save the password.

<form id="loginform" action="login.php" onSubmit="return login(this);">
 <input name="username" type="text" />
 <input name="password" type="password" />
 <input name="doLogin"  type="submit" value="Login" />
</form>

Using this method, the browser should offer to save the password.


Here's the Javascript used in both methods:

function login(f){
    var username = f.username.value;
    var password = f.password.value;

    /* Make your validation and ajax magic here. */

    return false; //or the form will post your data to login.php
}

What is the __del__ method, How to call it?

The __del__ method, it will be called when the object is garbage collected. Note that it isn't necessarily guaranteed to be called though. The following code by itself won't necessarily do it:

del obj

The reason being that del just decrements the reference count by one. If something else has a reference to the object, __del__ won't get called.

There are a few caveats to using __del__ though. Generally, they usually just aren't very useful. It sounds to me more like you want to use a close method or maybe a with statement.

See the python documentation on __del__ methods.

One other thing to note: __del__ methods can inhibit garbage collection if overused. In particular, a circular reference that has more than one object with a __del__ method won't get garbage collected. This is because the garbage collector doesn't know which one to call first. See the documentation on the gc module for more info.

What is the best free memory leak detector for a C/C++ program and its plug-in DLLs?

As several of my friend has posted there are many free leak detectors for C++. All of that will cause overhead when running your code, approximatly 20% slower. I preffer Visual Leak Detector for Visual C++ 2008/2010/2012 , you can download the source code from - enter link description here .

Remove a fixed prefix/suffix from a string in Bash

Small and universal solution:

expr "$string" : "$prefix\(.*\)$suffix"

Android: Pass data(extras) to a fragment

There is a simple why that I prefered to the bundle due to the no duplicate data in memory. It consists of a init public method for the fragment

private ArrayList<Music> listMusics = new ArrayList<Music>();
private ListView listMusic;


public static ListMusicFragment createInstance(List<Music> music) {
    ListMusicFragment fragment = new ListMusicFragment();
    fragment.init(music);
    return fragment;
}

public void init(List<Music> music){
    this.listMusic = music;
}

@Override
public View onCreateView(LayoutInflater inflater, ViewGroup container, 
    Bundle savedInstanceState)
{

    View view = inflater.inflate(R.layout.musiclistview, container, false);
    listMusic = (ListView) view.findViewById(R.id.musicListView);
    listMusic.setAdapter(new MusicBaseAdapter(getActivity(), listMusics));

    return view;
}
}

In two words, you create an instance of the fragment an by the init method (u can call it as u want) you pass the reference of your list without create a copy by serialization to the instance of the fragment. This is very usefull because if you change something in the list u will get it in the other parts of the app and ofcourse, you use less memory.

WHERE IS NULL, IS NOT NULL or NO WHERE clause depending on SQL Server parameter value

An other way of CASE:

SELECT *  
FROM MyTable
WHERE 1 = CASE WHEN @myParm = value1 AND MyColumn IS NULL     THEN 1 
               WHEN @myParm = value2 AND MyColumn IS NOT NULL THEN 1 
               WHEN @myParm = value3                          THEN 1 
          END

Reading string from input with space character?

If you need to read more than one line, need to clear buffer. Example:

int n;
scanf("%d", &n);
char str[1001];
char temp;
scanf("%c",&temp); // temp statement to clear buffer
scanf("%[^\n]",str);

PHP - syntax error, unexpected T_CONSTANT_ENCAPSED_STRING

$out.='<option value="'.$key.'">'.$value["name"];

me funciono con esta

"<a  href='javascript:void(0)' onclick='cargar_datos_cliente(\"$row->DSC_EST\")' class='button micro asignar margin-none'>Editar</a>";

How do I delete specific characters from a particular String in Java?

You can use replaceAll() method :

String.replaceAll(",", "");
String.replaceAll("\\.", "");
String.replaceAll("\\(", "");

etc..

How to format strings using printf() to get equal length in the output

printf allows formatting with width specifiers. For example,

printf( "%-30s %s\n", "Starting initialization...", "Ok." );

You would use a negative width specifier to indicate left-justification because the default is to use right-justification.

Jersey stopped working with InjectionManagerFactory not found

Here is the reason. Starting from Jersey 2.26, Jersey removed HK2 as a hard dependency. It created an SPI as a facade for the dependency injection provider, in the form of the InjectionManager and InjectionManagerFactory. So for Jersey to run, we need to have an implementation of the InjectionManagerFactory. There are two implementations of this, which are for HK2 and CDI. The HK2 dependency is the jersey-hk2 others are talking about.

<dependency>
    <groupId>org.glassfish.jersey.inject</groupId>
    <artifactId>jersey-hk2</artifactId>
    <version>2.26</version>
</dependency>

The CDI dependency is

<dependency>
    <groupId>org.glassfish.jersey.inject</groupId>
    <artifactId>jersey-cdi2-se</artifactId>
    <version>2.26</version>
</dependency>

This (jersey-cdi2-se) should only be used for SE environments and not EE environments.

Jersey made this change to allow others to provide their own dependency injection framework. They don't have any plans to implement any other InjectionManagers, though others have made attempts at implementing one for Guice.

installing python packages without internet and using source code as .tar.gz and .whl

This is how I handle this case:

On the machine where I have access to Internet:

mkdir keystone-deps
pip download python-keystoneclient -d "/home/aviuser/keystone-deps"
tar cvfz keystone-deps.tgz keystone-deps

Then move the tar file to the destination machine that does not have Internet access and perform the following:

tar xvfz keystone-deps.tgz
cd keystone-deps
pip install python_keystoneclient-2.3.1-py2.py3-none-any.whl -f ./ --no-index

You may need to add --no-deps to the command as follows:

pip install python_keystoneclient-2.3.1-py2.py3-none-any.whl -f ./ --no-index --no-deps

Cleanest way to write retry logic?

You might also consider adding the exception type you want to retry for. For instance is this a timeout exception you want to retry? A database exception?

RetryForExcpetionType(DoSomething, typeof(TimeoutException), 5, 1000);

public static void RetryForExcpetionType(Action action, Type retryOnExceptionType, int numRetries, int retryTimeout)
{
    if (action == null)
        throw new ArgumentNullException("action");
    if (retryOnExceptionType == null)
        throw new ArgumentNullException("retryOnExceptionType");
    while (true)
    {
        try
        {
            action();
            return;
        }
        catch(Exception e)
        {
            if (--numRetries <= 0 || !retryOnExceptionType.IsAssignableFrom(e.GetType()))
                throw;

            if (retryTimeout > 0)
                System.Threading.Thread.Sleep(retryTimeout);
        }
    }
}

You might also note that all of the other examples have a similar issue with testing for retries == 0 and either retry infinity or fail to raise exceptions when given a negative value. Also Sleep(-1000) will fail in the catch blocks above. Depends on how 'silly' you expect people to be but defensive programming never hurts.

How to remove padding around buttons in Android?

For me the problem turned out to be minHeight and minWidth on some of the Android themes.

On the Button element, add:

<Button android:minHeight="0dp" android:minWidth="0dp" ...

Or in your button's style:

<item name="android:minHeight">0dp</item>
<item name="android:minWidth">0dp</item>

Angularjs autocomplete from $http

the easiest way to do that in angular or angularjs without external modules or directives is using list and datalist HTML5. You just get a json and use ng-repeat for feeding the options in datalist. The json you can fetch it from ajax.

in this example:

  • ctrl.query is the query that you enter when you type.
  • ctrl.msg is the message that is showing in the placeholder
  • ctrl.dataList is the json fetched

then you can add filters and orderby in the ng-reapet

!! list and datalist id must have the same name !!

 <input type="text" list="autocompleList" ng-model="ctrl.query" placeholder={{ctrl.msg}}>
<datalist id="autocompleList">
        <option ng-repeat="Ids in ctrl.dataList value={{Ids}}  >
</datalist>

UPDATE : is native HTML5 but be carreful with the type browser and version. check it out : https://caniuse.com/#search=datalist.

Transmitting newline character "\n"

Try using %0A in the URL, just like you've used %20 instead of the space character.

How to get back to most recent version in Git?

To return to the latest version:

git checkout <branch-name> 

For example, git checkout master or git checkout dev

How do you log all events fired by an element in jQuery?

I have no idea why no-one uses this... (maybe because it's only a webkit thing)

Open console:

monitorEvents(document.body); // logs all events on the body

monitorEvents(document.body, 'mouse'); // logs mouse events on the body

monitorEvents(document.body.querySelectorAll('input')); // logs all events on inputs

How to use the 'main' parameter in package.json?

As far as I know, it's the main entry point to your node package (library) for npm. It's needed if your npm project becomes a node package (library) which can be installed via npm by others.


Let's say you have a library with a build/, dist/, or lib/ folder. In this folder, you got the following compiled file for your library:

-lib/
--bundle.js

Then in your package.json, you tell npm how to access the library (node package):

{
  "name": "my-library-name",
  "main": "lib/bundle.js",
  ...
}

After installing the node package with npm to your JS project, you can import functionalities from your bundled bundle.js file:

import { add, subtract } from 'my-library-name';

This holds also true when using Code Splitting (e.g. Webpack) for your library. For instance, this webpack.config.js makes use of code splitting the project into multiple bundles instead of one.

module.exports = {
  entry: {
    main: './src/index.js',
    add: './src/add.js',
    subtract: './src/subtract.js',
  },
  output: {
    path: `${__dirname}/lib`,
    filename: '[name].js',
    library: 'my-library-name',
    libraryTarget: 'umd',
  },
  ...
}

Still, you would define one main entry point to your library in your package.json:

{
  "name": "my-library-name",
  "main": "lib/main.js",
  ...
}

Then when using the library, you can import your files from your main entry point:

import { add, subtract } from 'my-library-name';

However, you can also bypass the main entry point from the package.json and import the code splitted bundles:

import add from 'my-library-name/lib/add';
import subtract from 'my-library-name/lib/subtract';

After all, the main property in your package.json only points to your main entry point file of your library.

How to remove first 10 characters from a string?

There is no need to specify the length into the Substring method. Therefore:

string s = hello world;
string p = s.Substring(3);

p will be:

"lo world".

The only exception you need to cater for is ArgumentOutOfRangeException if startIndex is less than zero or greater than the length of this instance.

Better way to find last used row

I use this routine to find the count of data rows. There is a minimum of overhead required, but by counting using a decreasing scale, even a very large result requires few iterations. For example, a result of 28,395 would only require 2 + 8 + 3 + 9 + 5, or 27 times through the loop, instead of a time-expensive 28,395 times.

Even were we to multiply that by 10 (283,950), the iteration count is the same 27 times.

Dim lWorksheetRecordCountScaler as Long
Dim lWorksheetRecordCount as Long

Const sDataColumn = "A"   '<----Set to column that has data in all rows (Code, ID, etc.)

    'Count the data records
    lWorksheetRecordCountScaler = 100000  'Begin by counting in 100,000-record bites
    lWorksheetRecordCount = lWorksheetRecordCountScaler

    While lWorksheetRecordCountScaler >= 1

        While Sheets("Sheet2").Range(sDataColumn & lWorksheetRecordCount + 2).Formula > " "
            lWorksheetRecordCount = lWorksheetRecordCount + lWorksheetRecordCountScaler
        Wend

        'To the beginning of the previous bite, count 1/10th of the scale from there
        lWorksheetRecordCount = lWorksheetRecordCount - lWorksheetRecordCountScaler
        lWorksheetRecordCountScaler = lWorksheetRecordCountScaler / 10

    Wend

    lWorksheetRecordCount = lWorksheetRecordCount + 1   'Final answer

System.Data.SqlClient.SqlException: Invalid object name 'dbo.Projects'

Delete _MigrationHistory table in (yourdatabseName > Tables > System Tables) if you already have in your database and then run below command in package manager console

PM> update-database

How to play only the audio of a Youtube video using HTML 5?

The answer is simple: Use a 3rd party product like jwplayer or similar, then set it to the minimal player size which is the audio player size (only shows player controls).

Voila.

Been using this for over 8 years.

Eclipse reports rendering library more recent than ADT plug-in

Please try once uninstalling from Help-->Installation details

and try again installing using http://dl-ssl.google.com/android/eclipse/

How to handle anchor hash linking in AngularJS

This was my solution using a directive which seems more Angular-y because we're dealing with the DOM:

Plnkr over here

github

CODE

angular.module('app', [])
.directive('scrollTo', function ($location, $anchorScroll) {
  return function(scope, element, attrs) {

    element.bind('click', function(event) {
        event.stopPropagation();
        var off = scope.$on('$locationChangeStart', function(ev) {
            off();
            ev.preventDefault();
        });
        var location = attrs.scrollTo;
        $location.hash(location);
        $anchorScroll();
    });

  };
});

HTML

<ul>
  <li><a href="" scroll-to="section1">Section 1</a></li>
  <li><a href="" scroll-to="section2">Section 2</a></li>
</ul>

<h1 id="section1">Hi, I'm section 1</h1>
<p>
Zombie ipsum reversus ab viral inferno, nam rick grimes malum cerebro. De carne lumbering animata corpora quaeritis. 
 Summus brains sit??, morbo vel maleficia? De apocalypsi gorger omero undead survivor dictum mauris. 
Hi mindless mortuis soulless creaturas, imo evil stalking monstra adventus resi dentevil vultus comedat cerebella viventium. 
Nescio brains an Undead zombies. Sicut malus putrid voodoo horror. Nigh tofth eliv ingdead.
</p>

<h1 id="section2">I'm totally section 2</h1>
<p>
Zombie ipsum reversus ab viral inferno, nam rick grimes malum cerebro. De carne lumbering animata corpora quaeritis. 
 Summus brains sit??, morbo vel maleficia? De apocalypsi gorger omero undead survivor dictum mauris. 
Hi mindless mortuis soulless creaturas, imo evil stalking monstra adventus resi dentevil vultus comedat cerebella viventium. 
Nescio brains an Undead zombies. Sicut malus putrid voodoo horror. Nigh tofth eliv ingdead.
</p>

I used the $anchorScroll service. To counteract the page-refresh that goes along with the hash changing I went ahead and cancelled the locationChangeStart event. This worked for me because I had a help page hooked up to an ng-switch and the refreshes would esentially break the app.

Nested iframes, AKA Iframe Inception

You should use live method for elements which are rendered later, like colorbox, hidden fields or iframe

$(".inverter-value").live("change",function() {
     elem = this
    $.ajax({
      url: '/main/invertor_attribute/',
      type: 'POST',
      aysnc: false,
      data: {id: $(this).val() },
      success: function(data){
       // code
      },
      dataType: 'html'
    });
  });

Definition of a Balanced Tree

There's no difference between these two things. Think about it.

Let's take a simpler definition, "A positive number is even if it is zero or that number minus two is even." Does this say 8 is even if 6 is even? Or does this say 8 is even if 6, 4, 2, and 0 are even?

There's no difference. If it says 8 is even if 6 is even, it also says 6 is even if 4 is even. And thus it also says 4 is even if 2 is even. And thus it says 2 is even if 0 is even. So if it says 8 is even if 6 is even, it (indirectly) says 8 is even if 6, 4, 2, and 0 are even.

It's the same thing here. Any indirect sub-tree can be found by a chain of direct sub-trees. So even if it only applies directly to direct sub-trees, it still applies indirectly to all sub-trees (and thus all nodes).

Importing large sql file to MySql via command line

The solution I use for large sql restore is a mysqldumpsplitter script. I split my sql.gz into individual tables. then load up something like mysql workbench and process it as a restore to the desired schema.

Here is the script https://github.com/kedarvj/mysqldumpsplitter

And this works for larger sql restores, my average on one site I work with is a 2.5gb sql.gz file, 20GB uncompressed, and ~100Gb once restored fully

SOAP vs REST (differences)

A lot of these answers entirely forgot to mention hypermedia controls (HATEOAS) which is completely fundamental to REST. A few others touched on it, but didn't really explain it so well.

This article should explain the difference between the concepts, without getting into the weeds on specific SOAP features.

How to change facet labels?

Simple solution (from here):

p <- ggplot(mtcars, aes(disp, drat)) + geom_point()
# Example (old labels)
p + facet_wrap(~am)


to_string <- as_labeller(c(`0` = "Zero", `1` = "One"))
# Example (New labels)
p + facet_wrap(~am, labeller = to_string)

Why is there no xrange function in Python3?

One way to fix up your python2 code is:

import sys

if sys.version_info >= (3, 0):
    def xrange(*args, **kwargs):
        return iter(range(*args, **kwargs))

How to split elements of a list?

myList = [i.split('\t')[0] for i in myList] 

Can't connect to MySQL server error 111

111 means connection refused, which in turn means that your mysqld only listens to the localhost interface.

To alter it you may want to look at the bind-address value in the mysqld section of your my.cnf file.

How to copy directory recursively in python and overwrite all?

Have a look at the shutil package, especially rmtree and copytree. You can check if a file / path exists with os.paths.exists(<path>).

import shutil
import os

def copy_and_overwrite(from_path, to_path):
    if os.path.exists(to_path):
        shutil.rmtree(to_path)
    shutil.copytree(from_path, to_path)

Vincent was right about copytree not working, if dirs already exist. So distutils is the nicer version. Below is a fixed version of shutil.copytree. It's basically copied 1-1, except the first os.makedirs() put behind an if-else-construct:

import os
from shutil import *
def copytree(src, dst, symlinks=False, ignore=None):
    names = os.listdir(src)
    if ignore is not None:
        ignored_names = ignore(src, names)
    else:
        ignored_names = set()

    if not os.path.isdir(dst): # This one line does the trick
        os.makedirs(dst)
    errors = []
    for name in names:
        if name in ignored_names:
            continue
        srcname = os.path.join(src, name)
        dstname = os.path.join(dst, name)
        try:
            if symlinks and os.path.islink(srcname):
                linkto = os.readlink(srcname)
                os.symlink(linkto, dstname)
            elif os.path.isdir(srcname):
                copytree(srcname, dstname, symlinks, ignore)
            else:
                # Will raise a SpecialFileError for unsupported file types
                copy2(srcname, dstname)
        # catch the Error from the recursive copytree so that we can
        # continue with other files
        except Error, err:
            errors.extend(err.args[0])
        except EnvironmentError, why:
            errors.append((srcname, dstname, str(why)))
    try:
        copystat(src, dst)
    except OSError, why:
        if WindowsError is not None and isinstance(why, WindowsError):
            # Copying file access times may fail on Windows
            pass
        else:
            errors.extend((src, dst, str(why)))
    if errors:
        raise Error, errors

How to show disable HTML select option in by default?

 selected disabled="true"

Use this. It will work in new browsers

async for loop in node.js

I've reduced your code sample to the following lines to make it easier to understand the explanation of the concept.

var results = [];
var config = JSON.parse(queries);
for (var key in config) {
    var query = config[key].query;
    search(query, function(result) {
        results.push(result);
    });
}
res.writeHead( ... );
res.end(results);

The problem with the previous code is that the search function is asynchronous, so when the loop has ended, none of the callback functions have been called. Consequently, the list of results is empty.

To fix the problem, you have to put the code after the loop in the callback function.

    search(query, function(result) {
        results.push(result);
        // Put res.writeHead( ... ) and res.end(results) here
    });

However, since the callback function is called multiple times (once for every iteration), you need to somehow know that all callbacks have been called. To do that, you need to count the number of callbacks, and check whether the number is equal to the number of asynchronous function calls.

To get a list of all keys, use Object.keys. Then, to iterate through this list, I use .forEach (you can also use for (var i = 0, key = keys[i]; i < keys.length; ++i) { .. }, but that could give problems, see JavaScript closure inside loops – simple practical example).

Here's a complete example:

var results = [];
var config = JSON.parse(queries);
var onComplete = function() {
    res.writeHead( ... );
    res.end(results);
};
var keys = Object.keys(config);
var tasksToGo = keys.length;
if (tasksToGo === 0) {
   onComplete();
} else {
    // There is at least one element, so the callback will be called.
    keys.forEach(function(key) {
        var query = config[key].query;
        search(query, function(result) {
            results.push(result);
            if (--tasksToGo === 0) {
                // No tasks left, good to go
                onComplete();
            }
        });
    });
}

Note: The asynchronous code in the previous example are executed in parallel. If the functions need to be called in a specific order, then you can use recursion to get the desired effect:

var results = [];
var config = JSON.parse(queries);
var keys = Object.keys(config);
(function next(index) {
    if (index === keys.length) { // No items left
        res.writeHead( ... );
        res.end(results);
        return;
    }
    var key = keys[index];
    var query = config[key].query;
    search(query, function(result) {
        results.push(result);
        next(index + 1);
    });
})(0);

What I've shown are the concepts, you could use one of the many (third-party) NodeJS modules in your implementation, such as async.

How to resize images proportionally / keeping the aspect ratio?

In order to determine the aspect ratio, you need to have a ratio to aim for.

Height

function getHeight(length, ratio) {
  var height = ((length)/(Math.sqrt((Math.pow(ratio, 2)+1))));
  return Math.round(height);
}

Width

function getWidth(length, ratio) {
  var width = ((length)/(Math.sqrt((1)/(Math.pow(ratio, 2)+1))));
  return Math.round(width);
}

In this example I use 16:10 since this the typical monitor aspect ratio.

var ratio = (16/10);
var height = getHeight(300,ratio);
var width = getWidth(height,ratio);

console.log(height);
console.log(width);

Results from above would be 147 and 300

How to set width to 100% in WPF

You could use HorizontalContentAlignment="Stretch" as follows:

<ListBox HorizontalContentAlignment="Stretch"/>

Tkinter: How to use threads to preventing main event loop from "freezing"

I have used RxPY which has some nice threading functions to solve this in a fairly clean manner. No queues, and I have provided a function that runs on the main thread after completion of the background thread. Here is a working example:

import rx
from rx.scheduler import ThreadPoolScheduler
import time
import tkinter as tk

class UI:
   def __init__(self):
      self.root = tk.Tk()
      self.pool_scheduler = ThreadPoolScheduler(1) # thread pool with 1 worker thread
      self.button = tk.Button(text="Do Task", command=self.do_task).pack()

   def do_task(self):
      rx.empty().subscribe(
         on_completed=self.long_running_task, 
         scheduler=self.pool_scheduler
      )

   def long_running_task(self):
      # your long running task here... eg:
      time.sleep(3)
      # if you want a callback on the main thread:
      self.root.after(5, self.on_task_complete)

   def on_task_complete(self):
       pass # runs on main thread

if __name__ == "__main__":
    ui = UI()
    ui.root.mainloop()

Another way to use this construct which might be cleaner (depending on preference):

tk.Button(text="Do Task", command=self.button_clicked).pack()

...

def button_clicked(self):

   def do_task(_):
      time.sleep(3) # runs on background thread
             
   def on_task_done():
      pass # runs on main thread

   rx.just(1).subscribe(
      on_next=do_task, 
      on_completed=lambda: self.root.after(5, on_task_done), 
      scheduler=self.pool_scheduler
   )

Convert cells(1,1) into "A1" and vice versa

The Address property of a cell can get this for you:

MsgBox Cells(1, 1).Address(RowAbsolute:=False, ColumnAbsolute:=False)

returns A1.

The other way around can be done with the Row and Column property of Range:

MsgBox Range("A1").Row & ", " & Range("A1").Column

returns 1,1.

How can I replace every occurrence of a String in a file with PowerShell?

(Get-Content file.txt) | 
Foreach-Object {$_ -replace '\[MYID\]','MyValue'}  | 
Out-File file.txt

Note the parentheses around (Get-Content file.txt) is required:

Without the parenthesis the content is read, one line at a time, and flows down the pipeline until it reaches out-file or set-content, which tries to write to the same file, but it's already open by get-content and you get an error. The parenthesis causes the operation of content reading to be performed once (open, read and close). Only then when all lines have been read, they are piped one at a time and when they reach the last command in the pipeline they can be written to the file. It's the same as $content=content; $content | where ...

Echo newline in Bash prints literal \n

Simply type

echo

to get a new line

Selenium Error - The HTTP request to the remote WebDriver timed out after 60 seconds

For ChromeDriver the below worked for me:

string chromeDriverDirectory = "C:\\temp\\2.37";
 var options = new ChromeOptions();
 options.AddArgument("-no-sandbox");
 driver = new ChromeDriver(chromeDriverDirectory, options, 
 TimeSpan.FromMinutes(2));

Selenium version 3.11, ChromeDriver 2.37

CodeIgniter Active Record not equal

This should work (which you have tried)

$this->db->where_not_in('emailsToCampaigns.campaignId', $campaignId);

How to format time since xxx e.g. “4 minutes ago” similar to Stack Exchange sites

Can also use the dayjs relativeTime plugin to solve this.

import * as dayjs from 'dayjs';
import * as relativeTime from 'dayjs/plugin/relativeTime';

dayjs.extend(relativeTime);
dayjs(dayjs('1990')).fromNow(); // x years ago

Python Selenium Chrome Webdriver

Here's a simpler solution: install python-chromedrive package, import it in your script, and it's done.

Step by step:
1. pip install chromedriver-binary
2. import the package

from selenium import webdriver
import chromedriver_binary  # Adds chromedriver binary to path

driver = webdriver.Chrome()
driver.get("http://www.python.org")

Reference: https://pypi.org/project/chromedriver-binary/

Add/Delete table rows dynamically using JavaScript

Javascript dynamically adding table data.

SCRIPT

function addRow(tableID) {
    var table = document.getElementById(tableID);
    var rowCount = table.rows.length;
    var colCount = table.rows[0].cells.length;    
    var validate_Noof_columns = (colCount - 1); // •No Of Columns to be Validated on Text.
    for(var j = 0; j < colCount; j++) { 
        var text = window.document.getElementById('input'+j).value;

        if (j == validate_Noof_columns) {
            row = table.insertRow(2); // •location of new row.
            for(var i = 0; i < colCount; i++) {       
            var text = window.document.getElementById('input'+i).value;
            var newcell = row.insertCell(i);
                if(i == (colCount - 1)) {  // Replace last column with delete button
    newcell.innerHTML = "<INPUT type='button' value='X' onclick='removeRow(this)'/>"; break;
                } else  {
                    newcell.innerHTML = text;
                    window.document.getElementById('input'+i).value = '';
                }
            }   
        }else if (text != 'undefined' && text.trim() == ''){ 
            alert('input'+j+' is EMPTY');break;
        }  
    }   
}
function removeRow(onclickTAG) {
    // Iterate till we find TR tag. 
    while ( (onclickTAG = onclickTAG.parentElement)  && onclickTAG.tagName != 'TR' );
            onclickTAG.parentElement.removeChild(onclickTAG);      
}

HTMl

<div align='center'>
<TABLE id='dataTable' border='1' >
<TBODY>
    <TR><th align='center'><b>First Name:</b></th>
        <th align='center' colspan='2'><b>Last  Name:</b></th>
        <th></th>
    </TR>    
    <TR><TD ><INPUT id='input0' type="text"/></TD>              
        <TD ><INPUT id='input1' type='text'/></TD>
        <TD>
<INPUT type='button' id='input2' value='+' onclick="addRow('dataTable')" />
        </TD>
    </TR>
</TBODY> 
</TABLE>
</div>

Example : jsfiddle

Check if a Windows service exists and delete in PowerShell

PowerShell Core (v6+) now has a Remove-Service cmdlet.

I don't know about plans to back-port it to Windows PowerShell, where it is not available as of v5.1.

Example:

# PowerShell *Core* only (v6+)
Remove-Service someservice

Note that invocation fails if the service doesn't exist, so to only remove it if it currently exists, you could do:

# PowerShell *Core* only (v6+)
$name = 'someservice'
if (Get-Service $name -ErrorAction Ignore) {
  Remove-Service $name
}

What is the command to exit a Console application in C#?

Several options, by order of most appropriate way:

  1. Return an int from the Program.Main method
  2. Throw an exception and don't handle it anywhere (use for unexpected error situations)
  3. To force termination elsewhere, System.Environment.Exit (not portable! see below)

Edited 9/2013 to improve readability

Returning with a specific exit code: As Servy points out in the comments, you can declare Main with an int return type and return an error code that way. So there really is no need to use Environment.Exit unless you need to terminate with an exit code and can't possibly do it in the Main method. Most probably you can avoid that by throwing an exception, and returning an error code in Main if any unhandled exception propagates there. If the application is multi-threaded you'll probably need even more boilerplate to properly terminate with an exit code so you may be better off just calling Environment.Exit.

Another point against using Evironment.Exit - even when writing multi-threaded applications - is reusability. If you ever want to reuse your code in an environment that makes Environment.Exit irrelevant (such as a library that may be used in a web server), the code will not be portable. The best solution still is, in my opinion, to always use exceptions and/or return values that represent that the method reached some error/finish state. That way, you can always use the same code in any .NET environment, and in any type of application. If you are writing specifically an app that needs to return an exit code or to terminate in a way similar to what Environment.Exit does, you can then go ahead and wrap the thread at the highest level and handle the errors/exceptions as needed.

How to configure the web.config to allow requests of any length

I had to add [AllowAnonymous] to the ActionResult functions in my login page because the user was not authenticated yet.

How do I remove a property from a JavaScript object?

The delete operator is used to remove properties from objects.

const obj = { foo: "bar" }
delete obj.foo
obj.hasOwnProperty("foo") // false

Note that, for arrays, this is not the same as removing an element. To remove an element from an array, use Array#splice or Array#pop. For example:

arr // [0, 1, 2, 3, 4]
arr.splice(3,1); // 3
arr // [0, 1, 2, 4]

Details

delete in JavaScript has a different function to that of the keyword in C and C++: it does not directly free memory. Instead, its sole purpose is to remove properties from objects.

For arrays, deleting a property corresponding to an index, creates a sparse array (ie. an array with a "hole" in it). Most browsers represent these missing array indices as "empty".

var array = [0, 1, 2, 3]
delete array[2] // [0, 1, empty, 3]

Note that delete does not relocate array[3] into array[2].

Different built-in functions in JavaScript handle sparse arrays differently.

  • for...in will skip the empty index completely.

  • A traditional for loop will return undefined for the value at the index.

  • Any method using Symbol.iterator will return undefined for the value at the index.

  • forEach, map and reduce will simply skip the missing index.

So, the delete operator should not be used for the common use-case of removing elements from an array. Arrays have a dedicated methods for removing elements and reallocating memory: Array#splice() and Array#pop.

Array#splice(start[, deleteCount[, item1[, item2[, ...]]]])

Array#splice mutates the array, and returns any removed indices. deleteCount elements are removed from index start, and item1, item2... itemN are inserted into the array from index start. If deleteCount is omitted then elements from startIndex are removed to the end of the array.

let a = [0,1,2,3,4]
a.splice(2,2) // returns the removed elements [2,3]
// ...and `a` is now [0,1,4]

There is also a similarly named, but different, function on Array.prototype: Array#slice.

Array#slice([begin[, end]])

Array#slice is non-destructive, and returns a new array containing the indicated indices from start to end. If end is left unspecified, it defaults to the end of the array. If end is positive, it specifies the zero-based non-inclusive index to stop at. If end is negative it, it specifies the index to stop at by counting back from the end of the array (eg. -1 will omit the final index). If end <= start, the result is an empty array.

let a = [0,1,2,3,4]
let slices = [
    a.slice(0,2),
    a.slice(2,2),
    a.slice(2,3),
    a.slice(2,5) ]

//   a           [0,1,2,3,4]
//   slices[0]   [0 1]- - -   
//   slices[1]    - - - - -
//   slices[2]    - -[3]- -
//   slices[3]    - -[2 4 5]

Array#pop

Array#pop removes the last element from an array, and returns that element. This operation changes the length of the array.

Simulate delayed and dropped packets on Linux

Haven't tried it myself, but this page has a list of plugin modules that run in Linux' built in iptables IP filtering system. One of the modules is called "nth", and allows you to set up a rule that will drop a configurable rate of the packets. Might be a good place to start, at least.

How do you uninstall a python package that was installed using distutils?

install --record + xargs rm

sudo python setup.py install --record files.txt
xargs sudo rm -rf < files.txt

removes all files and but leaves empty directories behind.

That is not ideal, it should be enough to avoid package conflicts.

And then you can finish the job manually if you want by reading files.txt, or be braver and automate empty directory removal as well.

A safe helper would be:

python-setup-uninstall() (
  sudo rm -f files.txt
  sudo python setup.py install --record files.txt && \
  xargs rm -rf < files.txt
  sudo rm -f files.txt
)

Tested in Python 2.7.6, Ubuntu 14.04.

Java "lambda expressions not supported at this language level"

To compile with Java 8 (lambdas etc) in IntelliJ IDEA 15;

  • CTRL + ALT + SHIFT + S or File / Project Structure

  • Open Project tab

  • Set Project SDK to compatible java version (1.8)

  • Set Project language level to 8

  • Open Modules tab

  • Set Language level to 8, click OK

  • CTRL + ALT + S or File / Settings

  • Build, Execution, Deployment / Compiler / Java Compiler

  • Change Target bytecode version to 1.8, click OK

What is the best or most commonly used JMX Console / Client

jminix is an embedded web based JMX console. Not sure if it's maintained any longer, but still.

Get file name from URI string in C#

You can just make a System.Uri object, and use IsFile to verify it's a file, then Uri.LocalPath to extract the filename.

This is much safer, as it provides you a means to check the validity of the URI as well.


Edit in response to comment:

To get just the full filename, I'd use:

Uri uri = new Uri(hreflink);
if (uri.IsFile) {
    string filename = System.IO.Path.GetFileName(uri.LocalPath);
}

This does all of the error checking for you, and is platform-neutral. All of the special cases get handled for you quickly and easily.

Editing legend (text) labels in ggplot

The legend titles can be labeled by specific aesthetic.

This can be achieved using the guides() or labs() functions from ggplot2 (more here and here). It allows you to add guide/legend properties using the aesthetic mapping.

Here's an example using the mtcars data set and labs():

ggplot(mtcars, aes(x=mpg, y=disp, size=hp, col=as.factor(cyl), shape=as.factor(gear))) +
  geom_point() +
  labs(x="miles per gallon", y="displacement", size="horsepower", 
       col="# of cylinders", shape="# of gears")

enter image description here

Answering the OP's question using guides():

# transforming the data from wide to long
require(reshape2)
dfm <- melt(df, id="TY")

# creating a scatterplot
ggplot(data = dfm, aes(x=TY, y=value, color=variable)) + 
  geom_point(size=5) +
  labs(title="Temperatures\n", x="TY [°C]", y="Txxx") +
  scale_color_manual(labels = c("T999", "T888"), values = c("blue", "red")) +
  theme_bw() +
  guides(color=guide_legend("my title"))  # add guide properties by aesthetic

enter image description here

How does Python return multiple values from a function?

mentioned also here, you can use this:

import collections
Point = collections.namedtuple('Point', ['x', 'y'])
p = Point(1, y=2)
>>> p.x, p.y
1 2
>>> p[0], p[1]
1 2

Telnet is not recognized as internal or external command

You can also try dism /online /Enable-Feature /FeatureName:TelnetClient

Run this command with "Run as an administrator"

Reference

Extreme wait-time when taking a SQL Server database offline

In my case i stopped Tomcat server . then immediately the DB went offline .

Data at the root level is invalid

This:

doc.LoadXml(HttpContext.Current.Server.MapPath("officeList.xml"));

should be:

doc.Load(HttpContext.Current.Server.MapPath("officeList.xml"));

LoadXml() is for loading an XML string, not a file name.

Is unsigned integer subtraction defined behavior?

The result of a subtraction generating a negative number in an unsigned type is well-defined:

  1. [...] A computation involving unsigned operands can never overflow, because a result that cannot be represented by the resulting unsigned integer type is reduced modulo the number that is one greater than the largest value that can be represented by the resulting type. (ISO/IEC 9899:1999 (E) §6.2.5/9)

As you can see, (unsigned)0 - (unsigned)1 equals -1 modulo UINT_MAX+1, or in other words, UINT_MAX.

Note that although it does say "A computation involving unsigned operands can never overflow", which might lead you to believe that it applies only for exceeding the upper limit, this is presented as a motivation for the actual binding part of the sentence: "a result that cannot be represented by the resulting unsigned integer type is reduced modulo the number that is one greater than the largest value that can be represented by the resulting type." This phrase is not restricted to overflow of the upper bound of the type, and applies equally to values too low to be represented.

rand() between 0 and 1

No, because RAND_MAX is typically expanded to MAX_INT. So adding one (apparently) puts it at MIN_INT (although it should be undefined behavior as I'm told), hence the reversal of sign.

To get what you want you will need to move the +1 outside the computation:

r = ((double) rand() / (RAND_MAX)) + 1;

Session state can only be used when enableSessionState is set to true either in a configuration

Following answer from below given path worked fine.

I found a solution that worked perfectly! Add the following to web.config:

<system.webServer>
<modules>
<!-- UrlRewriter code here -->
<remove name="Session" />
<add name="Session" type="System.Web.SessionState.SessionStateModule" preCondition="" />
</modules>
</system.webServer>

Hope this helps someone else!

How to get current time in milliseconds in PHP?

Use microtime(true) in PHP 5, or the following modification in PHP 4:

array_sum(explode(' ', microtime()));

A portable way to write that code would be:

function getMicrotime()
{
    if (version_compare(PHP_VERSION, '5.0.0', '<'))
    {
        return array_sum(explode(' ', microtime()));
    }

    return microtime(true);
}

CreateProcess error=2, The system cannot find the file specified

The complete first argument of exec is being interpreted as the executable. Use

p = rt.exec(new String[] {"winrar.exe", "x", "h:\\myjar.jar", "*.*", "h:\\new" }
            null, 
            dir);

Convert text to columns in Excel using VBA

Try this

Sub Txt2Col()
    Dim rng As Range

    Set rng = [C7]
    Set rng = Range(rng, Cells(Rows.Count, rng.Column).End(xlUp))

    rng.TextToColumns Destination:=rng, DataType:=xlDelimited, ' rest of your settings

Update: button click event to act on another sheet

Private Sub CommandButton1_Click()
    Dim rng As Range
    Dim sh As Worksheet

    Set sh = Worksheets("Sheet2")
    With sh
        Set rng = .[C7]
        Set rng = .Range(rng, .Cells(.Rows.Count, rng.Column).End(xlUp))

        rng.TextToColumns Destination:=rng, DataType:=xlDelimited, _
        TextQualifier:=xlDoubleQuote,  _
        ConsecutiveDelimiter:=False, _
        Tab:=False, _
        Semicolon:=False, _
        Comma:=True, 
        Space:=False, 
        Other:=False, _
        FieldInfo:=Array(Array(1, xlGeneralFormat), Array(2, xlGeneralFormat), Array(3, xlGeneralFormat)), _
        TrailingMinusNumbers:=True
    End With
End Sub

Note the .'s (eg .Range) they refer to the With statement object

How to configure port for a Spring Boot application

Providing the port number in application.properties file will resolve the issue

 server.port = 8080

"port depends on your choice, where you want to host the application"

chrome undo the action of "prevent this page from creating additional dialogs"

open a new window or tab with the same link.. the PREVENT option lasts per session only..

Create random list of integers in Python

Your question about performance is moot—both functions are very fast. The speed of your code will be determined by what you do with the random numbers.

However it's important you understand the difference in behaviour of those two functions. One does random sampling with replacement, the other does random sampling without replacement.

How can I loop over entries in JSON?

To decode json, you have to pass the json string. Currently you're trying to pass an object:

>>> response = urlopen(url)
>>> response
<addinfourl at 2146100812 whose fp = <socket._fileobject object at 0x7fe8cc2c>>

You can fetch the data with response.read().

adding multiple event listeners to one element

Maybe you can use a helper function like this:

// events and args should be of type Array
function addMultipleListeners(element,events,handler,useCapture,args){
  if (!(events instanceof Array)){
    throw 'addMultipleListeners: '+
          'please supply an array of eventstrings '+
          '(like ["click","mouseover"])';
  }
  //create a wrapper to be able to use additional arguments
  var handlerFn = function(e){
    handler.apply(this, args && args instanceof Array ? args : []);
  }
  for (var i=0;i<events.length;i+=1){
    element.addEventListener(events[i],handlerFn,useCapture);
  }
}

function handler(e) {
  // do things
};

// usage
addMultipleListeners(
    document.getElementById('first'),
    ['touchstart','click'],
    handler,
    false);

[Edit nov. 2020] This answer is pretty old. The way I solve this nowadays is by using an actions object where handlers are specified per event type, a data-attribute for an element to indicate which action should be executed on it and one generic document wide handler method (so event delegation).

_x000D_
_x000D_
const firstElemHandler = (elem, evt) =>
  elem.textContent = `You ${evt.type === "click" ? "clicked" : "touched"}!`;
const actions = {
  click: {
    firstElemHandler,
  },
  touchstart: {
    firstElemHandler,
  },
  mouseover: {
    firstElemHandler: elem => elem.textContent = "Now ... click me!",
    outerHandling: elem => {
      console.clear();
      console.log(`Hi from outerHandling, handle time ${
        new Date().toLocaleTimeString()}`);
    },
  }
};

Object.keys(actions).forEach(key => document.addEventListener(key, handle));

function handle(evt) {
  const origin = evt.target.closest("[data-action]");
  return origin &&
    actions[evt.type] &&
    actions[evt.type][origin.dataset.action] &&
    actions[evt.type][origin.dataset.action](origin, evt) ||
    true;
}
_x000D_
[data-action]:hover {
  cursor: pointer;
}
_x000D_
<div data-action="outerHandling">
  <div id="first" data-action="firstElemHandler">
    <b>Hover, click or tap</b>
  </div>
  this is handled too (on mouse over)
</div>
_x000D_
_x000D_
_x000D_

How to do a join in linq to sql with method syntax?

To add on to the other answers here, if you would like to create a new object of a third different type with a where clause (e.g. one that is not your Entity Framework object) you can do this:

public IEnumerable<ThirdNonEntityClass> demoMethod(IEnumerable<int> property1Values)
{
    using(var entityFrameworkObjectContext = new EntityFrameworkObjectContext )
    {
        var result = entityFrameworkObjectContext.SomeClass
            .Join(entityFrameworkObjectContext.SomeOtherClass,
                sc => sc.property1,
                soc => soc.property2,
                (sc, soc) => new {sc, soc})
            .Where(s => propertyValues.Any(pvals => pvals == es.sc.property1)
            .Select(s => new ThirdNonEntityClass 
            {
                dataValue1 = s.sc.dataValueA,
                dataValue2 = s.soc.dataValueB
            })
            .ToList();
    }

    return result;

}    

Pay special attention to the intermediate object that is created in the Where and Select clauses.

Note that here we also look for any joined objects that have a property1 that matches one of the ones in the input list.

I know this is a bit more complex than what the original asker was looking for, but hopefully it will help someone.

Access denied for user 'homestead'@'localhost' (using password: YES)

When you install Homestead, this creates a default "homestead" database in the VM. You should SSH into the VM homestead ssh and run your migrations from there. If you are working locally with no VM, you'll need to create your database manually. By default, the database should be called homestead, the username is homestead and the password is secret.

check this thread on laracasts or this blog post for more details


if you are getting

[PDOException] SQLSTATE[HY000] [2002] No such file or directory

try changing "host" in the /app/config/database.php file from "localhost" to "127.0.0.1" . you can find more details and other fixes here on this thread.

Also check whether you have specified the correct unix_socket . check this thread .

JavaScript function in href vs. onclick

One more thing that I noticed when using "href" with javascript:

The script in "href" attribute won't be executed if the time difference between 2 clicks was quite short.

For example, try to run following example and double click (fast!) on each link. The first link will be executed only once. The second link will be executed twice.

<script>
function myFunc() {
    var s = 0;
    for (var i=0; i<100000; i++) {
        s+=i;
    }
    console.log(s);
}
</script>
<a href="javascript:myFunc()">href</a>
<a href="#" onclick="javascript:myFunc()">onclick</a>

Reproduced in Chrome (double click) and IE11 (with triple click). In Chrome if you click fast enough you can make 10 clicks and have only 1 function execution.

Firefox works ok.

Finding rows that don't contain numeric data in Oracle

In contrast to SGB's answer, I prefer doing the regexp defining the actual format of my data and negating that. This allows me to define values like $DDD,DDD,DDD.DD In the OPs simple scenario, it would look like

SELECT * 
FROM table_with_column_to_search 
WHERE NOT REGEXP_LIKE(varchar_col_with_non_numerics, '^[0-9]+$');

which finds all non-positive integers. If you wau accept negatiuve integers also, it's an easy change, just add an optional leading minus.

SELECT * 
FROM table_with_column_to_search 
WHERE NOT REGEXP_LIKE(varchar_col_with_non_numerics, '^-?[0-9]+$');

accepting floating points...

SELECT * 
FROM table_with_column_to_search 
WHERE NOT REGEXP_LIKE(varchar_col_with_non_numerics, '^-?[0-9]+(\.[0-9]+)?$');

Same goes further with any format. Basically, you will generally already have the formats to validate input data, so when you will desire to find data that does not match that format ... it's simpler to negate that format than come up with another one; which in case of SGB's approach would be a bit tricky to do if you want more than just positive integers.

Finish all previous activities

If you are using startActivityForResult() in your previous activities, just override OnActivityResult() and call the finish(); method inside it in all activities.. This will do the job...

How to draw a rounded Rectangle on HTML Canvas?

    var canvas = document.createElement("canvas");
    document.body.appendChild(canvas);
    var ctx = canvas.getContext("2d");
    ctx.beginPath();
    ctx.moveTo(100,100);
    ctx.arcTo(0,100,0,0,30);
    ctx.arcTo(0,0,100,0,30);
    ctx.arcTo(100,0,100,100,30);
    ctx.arcTo(100,100,0,100,30);
    ctx.fill();

Checkout subdirectories in Git?

Actually, "narrow" or "partial" or "sparse" checkouts are under current, heavy development for Git. Note, you'll still have the full repository under .git. So, the other two posts are current for the current state of Git but it looks like we will be able to do sparse checkouts eventually. Checkout the mailing lists if you're interested in more details -- they're changing rapidly.

event.preventDefault() function not working in IE

if (e.preventDefault) {
    e.preventDefault();
} else {
    e.returnValue = false;
}

Tested on IE 9 and Chrome.

How to display a pdf in a modal window?

you can use iframe within your modal form so when u open the iframe window it open inside your your modal form . i hope you are rendering to some pdf opener with some url , if u have the pdf contents simply add the contents in a div in the modal form .

C# static class why use?

Static classes can be useful in certain situations, but there is a potential to abuse and/or overuse them, like most language features.

As Dylan Smith already mentioned, the most obvious case for using a static class is if you have a class with only static methods. There is no point in allowing developers to instantiate such a class.

The caveat is that an overabundance of static methods may itself indicate a flaw in your design strategy. I find that when you are creating a static function, its a good to ask yourself -- would it be better suited as either a) an instance method, or b) an extension method to an interface. The idea here is that object behaviors are usually associated with object state, meaning the behavior should belong to the object. By using a static function you are implying that the behavior shouldn't belong to any particular object.

Polymorphic and interface driven design are hindered by overusing static functions -- they cannot be overriden in derived classes nor can they be attached to an interface. Its usually better to have your 'helper' functions tied to an interface via an extension method such that all instances of the interface have access to that shared 'helper' functionality.

One situation where static functions are definitely useful, in my opinion, is in creating a .Create() or .New() method to implement logic for object creation, for instance when you want to proxy the object being created,

public class Foo
{
    public static Foo New(string fooString)
    {
        ProxyGenerator generator = new ProxyGenerator();

        return (Foo)generator.CreateClassProxy
             (typeof(Foo), new object[] { fooString }, new Interceptor()); 
    }

This can be used with a proxying framework (like Castle Dynamic Proxy) where you want to intercept / inject functionality into an object, based on say, certain attributes assigned to its methods. The overall idea is that you need a special constructor because technically you are creating a copy of the original instance with special added functionality.

First Or Create

Previous answer is obsolete. It's possible to achieve in one step since Laravel 5.3, firstOrCreate now has second parameter values, which is being used for new record, but not for search

$user = User::firstOrCreate([
    'email' => '[email protected]'
], [
    'firstName' => 'Taylor',
    'lastName' => 'Otwell'
]);

How to set div width using ng-style

The syntax of ng-style is not quite that. It accepts a dictionary of keys (attribute names) and values (the value they should take, an empty string unsets them) rather than only a string. I think what you want is this:

<div ng-style="{ 'width' : width, 'background' : bgColor }"></div>

And then in your controller:

$scope.width = '900px';
$scope.bgColor = 'red';

This preserves the separation of template and the controller: the controller holds the semantic values while the template maps them to the correct attribute name.

How can I extract audio from video with ffmpeg?

To extract the audio stream without re-encoding:

ffmpeg -i input-video.avi -vn -acodec copy output-audio.aac
  • -vn is no video.
  • -acodec copy says use the same audio stream that's already in there.

Read the output to see what codec it is, to set the right filename extension.

How do I create a timeline chart which shows multiple events? Eg. Metallica Band members timeline on wiki

A Stacked bar chart should suffice:

Setup data as follows

Name    Start       End         Duration (End - Start)
Fred    1/01/1981   1/06/1985    1612   
Bill    1/07/1985   1/11/2000    5602  
Joe     1/01/1980   1/12/2001    8005  
Jim     1/03/1999   1/01/2000    306  
  1. Plot Start and Duration as a stacked bar chart
  2. Set the X-Axis minimum to the desired start date
  3. Set the Fill Colour of thestart range to no fill
  4. Set the Fill of individual bars to suit

(example prepared in Excel 2010)

enter image description here

Difference between two numpy arrays in python

You can also use numpy.subtract

It has the advantage over the difference operator, -, that you do not have to transform the sequences (list or tuples) into a numpy arrays — you save the two commands:

array1 = np.array([1.1, 2.2, 3.3])
array2 = np.array([1, 2, 3])

Example: (Python 3.5)

import numpy as np
result = np.subtract([1.1, 2.2, 3.3], [1, 2, 3])
print ('the difference =', result)

which gives you

the difference = [ 0.1  0.2  0.3]

Remember, however, that if you try to subtract sequences (lists or tuples) with the - operator you will get an error. In this case, you need the above commands to transform the sequences in numpy arrays

Wrong Code:

print([1.1, 2.2, 3.3] - [1, 2, 3])

jquery click event not firing?

Might be useful to some : check for

pointer-events: none;

In the CSS. It prevents clicks from being caught by JS. I think it's relevant because the CSS might be the last place you'd look into in this kind of situation.

Convert character to Date in R

The easiest way is to use lubridate:

library(lubridate)
prods.all$Date2 <- mdy(prods.all$Date2)

This function automatically returns objects of class POSIXct and will work with either factors or characters.

Get current location of user in Android without using GPS or internet

No, you cannot currently get location without using GPS or internet.

Location techniques based on WiFi, Cellular, or Bluetooth work with the help of a large database that is constantly being updated. A device scans for transmitter IDs and then sends these in a query through the internet to a service such as Google, Apple, or Skyhook. That service responds with a location based on previous wireless surveys from known locations. Without internet access, you have to have a local copy of such a database and keep this up to date. For global usage, this is very impractical.

Theoretically, a mobile provider could provide local data service only but no access to the internet, and then answer location queries from mobile devices. Mobile providers don't do this; no one wants to pay for this kind of restricted data access. If you have data service through your mobile provider, then you have internet access.

In short, using LocationManager.NETWORK_PROVIDER or android.hardware.location.network to get location requires use of the internet.

Using the last known position requires you to have had GPS or internet access very recently. If you just had internet, presumably you can adjust your position or settings to get internet again. If your device has not had GPS or internet access, the last known position feature will not help you.

Without GPS or internet, you could:

  1. Take pictures of the night sky and use the current time to estimate your location based on a star chart. This would probably require additional equipment to ensure that the angles for your pictures are correctly measured.
  2. Use an accelerometer to track location starting from a known position. The accumulation of error in this kind of approach makes it impractical for most situations.

Java Array Sort descending?

I know that this is a quite old thread, but here is an updated version for Integers and Java 8:

Arrays.sort(array, (o1, o2) -> o2 - o1);

Note that it is "o1 - o2" for the normal ascending order (or Comparator.comparingInt()).

This also works for any other kinds of Objects. Say:

Arrays.sort(array, (o1, o2) -> o2.getValue() - o1.getValue());

npm can't find package.json

ok, try to go to the home "user@user:~$ " (cd + enter key), and npm install -g your your_module.

What is the difference between match_parent and fill_parent?

1. match_parent

When you set layout width and height as match_parent, it will occupy the complete area that the parent view has, i.e. it will be as big as the parent.

Note : If parent is applied a padding then that space would not be included.

When we create a layout.xml by default we have RelativeLayout as default parent View with android:layout_width="match_parent" and android:layout_height="match_parent" i.e it occupies the complete width and height of the mobile screen.

Also note that padding is applied to all sides,

android:paddingBottom="@dimen/activity_vertical_margin"
android:paddingLeft="@dimen/activity_horizontal_margin"
android:paddingRight="@dimen/activity_horizontal_margin"
android:paddingTop="@dimen/activity_vertical_margin"

Now lets add a sub-view LinearLayout and sets its layout_width="match_parent" and layout_height="match_parent", the graphical view would display something like this,

match_parent_example

Code

xmlns:tools="http://schemas.android.com/tools"
android:layout_width="match_parent"
android:layout_height="match_parent"
android:paddingBottom="@dimen/activity_vertical_margin"
android:paddingLeft="@dimen/activity_horizontal_margin"
android:paddingRight="@dimen/activity_horizontal_margin"
android:paddingTop="@dimen/activity_vertical_margin"
tools:context="com.code2care.android.togglebuttonexample.MainActivity" >

android:layout_width="match_parent"
android:layout_height="match_parent"
android:layout_alignParentLeft="true"
android:layout_alignParentTop="true"
android:layout_marginLeft="11dp"
android:background="#FFFFEE"
android:orientation="vertical" >

2. fill_parent :

This is same as match_parent, fill_parent was depreciated in API level 8. So if you are using API level 8 or above you must avoid using fill_parent

Lets follow the same steps as we did for match_parent, just instead use fill_parent everywhere.

You would see that there is no difference in behaviour in both fill_parent and match parent.

Android list view inside a scroll view

Do NEVER put a ListView inside of a ScrollView! You can find more information about that topic on Google. In your case, use a LinearLayout instead of the ListView and add the elements programmatically.

Android - How To Override the "Back" button so it doesn't Finish() my Activity?

I think what you want is not to override the back button (that just doesn't seem like a good idea - Android OS defines that behavior, why change it?), but to use the Activity Lifecycle and persist your settings/data in the onSaveInstanceState(Bundle) event.

@Override
onSaveInstanceState(Bundle frozenState) {
    frozenState.putSerializable("object_key",
        someSerializableClassYouWantToPersist);
    // etc. until you have everything important stored in the bundle
}

Then you use onCreate(Bundle) to get everything out of that persisted bundle and recreate your state.

@Override
onCreate(Bundle savedInstanceState) {
    if(savedInstanceState!=null){ //It could be null if starting the app.
        mCustomObject = savedInstanceState.getSerializable("object_key");
    }
    // etc. until you have reloaded everything you stored
}

Consider the above psuedo-code to point you in the right direction. Reading up on the Activity Lifecycle should help you determine the best way to accomplish what you're looking for.

C# How to determine if a number is a multiple of another?

Use the modulus (%) operator:

6 % 3 == 0
7 % 3 == 1

How do you create a foreign key relationship in a SQL Server CE (Compact Edition) Database?

I know it's a "very long time" since this question was first asked. Just in case, if it helps someone,

Adding relationships is well supported by MS via SQL Server Compact Tool Box (https://sqlcetoolbox.codeplex.com/). Just install it, then you would get the option to connect to the Compact Database using the Server Explorer Window. Right click on the primary table , select "Table Properties". You should have the following window, which contains "Add Relations" tab allowing you to add relations.

Add Relations Tab - SQL Server Compact Tool Box

AttributeError: 'str' object has no attribute 'append'

If you want to append a value to myList, use myList.append(s).

Strings are immutable -- you can't append to them.

Best XML Parser for PHP

It depends on what you are trying to do with the XML files. If you are just trying to read the XML file (like a configuration file), The Wicked Flea is correct in suggesting SimpleXML since it creates what amounts to nested ArrayObjects. e.g. value will be accessible by $xml->root->child.

If you are looking to manipulate the XML files you're probably best off using DOM XML

How to make div follow scrolling smoothly with jQuery?

Since this question is getting a lot of views and the tutorial linked in the most voted answer appears to be offline, I took the time to clean up this script.

See it live here: JSFiddle

JavaScript:

(function($) {
    var element = $('.follow-scroll'),
        originalY = element.offset().top;

    // Space between element and top of screen (when scrolling)
    var topMargin = 20;

    // Should probably be set in CSS; but here just for emphasis
    element.css('position', 'relative');

    $(window).on('scroll', function(event) {
        var scrollTop = $(window).scrollTop();

        element.stop(false, false).animate({
            top: scrollTop < originalY
                    ? 0
                    : scrollTop - originalY + topMargin
        }, 300);
    });
})(jQuery);

How to analyze a JMeter summary report?

Sample: Number of requests sent.

The Throughput: is the number of requests per unit of time (seconds, minutes, hours) that are sent to your server during the test.

The Response time: is the elapsed time from the moment when a given request is sent to the server until the moment when the last bit of information has returned to the client.

The throughput is the real load processed by your server during a run but it does not tell you anything about the performance of your server during this same run. This is the reason why you need both measures in order to get a real idea about your server’s performance during a run. The response time tells you how fast your server is handling a given load.

Average: This is the Average (Arithmetic mean µ = 1/n * Si=1…n xi) Response time of your total samples.

Min and Max are the minimum and maximum response time.

An important thing to understand is that the mean value can be very misleading as it does not show you how close (or far) your values are from the average.For this purpose, we need the Deviation value since Average value can be the Same for different response time of the samples!!

Deviation: The standard deviation (s) measures the mean distance of the values to their average (µ).It gives you a good idea of the dispersion or variability of the measures to their mean value.

The following equation show how the standard deviation (s) is calculated:

s = 1/n * v Si=1…n (xi-µ)2

For Details, see here!!

So, if the deviation value is low compared to the mean value, it will indicate you that your measures are not dispersed (or mostly close to the mean value) and that the mean value is significant.

Kb/sec: The throughput measured in Kilobytes per second.

Error % : Percent of requests with errors.

An example is always better to understand!!! I think, this article will help you.

How to get ER model of database from server with Workbench

On mac, press Command + R or got to Database -> Reverse Engineer and keep selecting your requirements and continue

enter image description here

How to set up fixed width for <td>?

Use d-flex instead of row for "tr" in Bootstrap 4

The thing is that "row" class takes more width then the parent container, which introduces issues.

_x000D_
_x000D_
<table class="table">_x000D_
  <tbody>_x000D_
    <tr class="d-flex">_x000D_
      <td class="col-sm-8">Hello</td>_x000D_
      <td class="col-sm-4">World</td>_x000D_
    </tr>_x000D_
    <tr class="d-flex">_x000D_
      <td class="col-sm-8">8 columns</td>_x000D_
      <td class="col-sm-4">4 columns</td>_x000D_
    </tr>_x000D_
  </tbody>_x000D_
</table>
_x000D_
_x000D_
_x000D_

Want to show/hide div based on dropdown box selection

<script src="http://ajax.googleapis.com/ajax/libs/jquery/1.10.2/jquery.min.js">
</script>
<script>
$(document).ready(function(){
    $('#purpose').on('change', function() {
      if ( this.value == '1')
      //.....................^.......
      {
           $("#business_new").hide();
        $("#business").show();
      }
      else  if ( this.value == '2')
      {
          $("#business").hide();
        $("#business_new").show();
      }
       else  
      {
        $("#business").hide();
      }
    });
});
</script>
<body>
<select id='purpose'>
<option value="0">Personal use</option>
<option value="1">Business use</option>
<option value="2">Passing on to a client</option>
</select>
<div style='display:none;' id='business'>Business Name<br/>&nbsp;
<br/>&nbsp;
    <input type='text' class='text' name='business' value size='20' />
    <input type='text' class='text' name='business' value size='20' />
    <br/>
</div>
<div style='display:none;' id='business_new'>Business Name<br/>&nbsp;
<br/>&nbsp;
    <input type='text' class='text' name='business' value="1254" size='20' />
    <input type='text' class='text' name='business' value size='20' />
    <br/>
</div>
</body>

Mockito: Mock private field initialization

In case you use Spring Test try org.springframework.test.util.ReflectionTestUtils

 ReflectionTestUtils.setField(testObject, "person", mockedPerson);

Best way to check if MySQL results returned in PHP?

If you would still like to perform the action if the $result is invalid:

if(!mysql_num_rows($result))
    // Do stuff

This will account for a 0 and the false that is returned by mysql_num_rows() on failure.

How to use java.String.format in Scala?

While all the previous responses are correct, they're all in Java. Here's a Scala example:

val placeholder = "Hello %s, isn't %s cool?"
val formatted = placeholder.format("Ivan", "Scala")

I also have a blog post about making format like Python's % operator that might be useful.

Hbase quickly count number of rows

You can use the count method in hbase to count the number of rows. But yes, counting rows of a large table can be slow.count 'tablename' [interval]

Return value is the number of rows.

This operation may take a LONG time (Run ‘$HADOOP_HOME/bin/hadoop jar hbase.jar rowcount’ to run a counting mapreduce job). Current count is shown every 1000 rows by default. Count interval may be optionally specified. Scan caching is enabled on count scans by default. Default cache size is 10 rows. If your rows are small in size, you may want to increase this parameter.

Examples:

hbase> count 't1'

hbase> count 't1', INTERVAL => 100000

hbase> count 't1', CACHE => 1000

hbase> count 't1', INTERVAL => 10, CACHE => 1000

The same commands also can be run on a table reference. Suppose you had a reference to table 't1', the corresponding commands would be:

hbase> t.count

hbase> t.count INTERVAL => 100000

hbase> t.count CACHE => 1000

hbase> t.count INTERVAL => 10, CACHE => 1000

How to develop or migrate apps for iPhone 5 screen resolution?

Peter, you should really take a look at Canappi, it does all that for you, all you have to do is specify the layout as such:

button mySubmitButton 'Sumbit' (100,100,100,30 + 0,88,0,0) { ... }

From there Canappi will generate the correct objective-c code that detects the device the app is running on and will use:

(100,100,100,30) for iPhone4
(100,**188**,100,30) for iPhone 5

Canappi works like Interface Builder and Story Board combined, except that it is in a textual form. If you already have XIB files, you can convert them so you don't have to recreate the entire UI from scratch.

Accessing Google Spreadsheets with C# using Google Data API

According to the .NET user guide:

Download the .NET client library:

Add these using statements:

using Google.GData.Client;
using Google.GData.Extensions;
using Google.GData.Spreadsheets;

Authenticate:

SpreadsheetsService myService = new SpreadsheetsService("exampleCo-exampleApp-1");
myService.setUserCredentials("[email protected]", "mypassword");

Get a list of spreadsheets:

SpreadsheetQuery query = new SpreadsheetQuery();
SpreadsheetFeed feed = myService.Query(query);

Console.WriteLine("Your spreadsheets: ");
foreach (SpreadsheetEntry entry in feed.Entries)
{
    Console.WriteLine(entry.Title.Text);
}

Given a SpreadsheetEntry you've already retrieved, you can get a list of all worksheets in this spreadsheet as follows:

AtomLink link = entry.Links.FindService(GDataSpreadsheetsNameTable.WorksheetRel, null);

WorksheetQuery query = new WorksheetQuery(link.HRef.ToString());
WorksheetFeed feed = service.Query(query);

foreach (WorksheetEntry worksheet in feed.Entries)
{
    Console.WriteLine(worksheet.Title.Text);
}

And get a cell based feed:

AtomLink cellFeedLink = worksheetentry.Links.FindService(GDataSpreadsheetsNameTable.CellRel, null);

CellQuery query = new CellQuery(cellFeedLink.HRef.ToString());
CellFeed feed = service.Query(query);

Console.WriteLine("Cells in this worksheet:");
foreach (CellEntry curCell in feed.Entries)
{
    Console.WriteLine("Row {0}, column {1}: {2}", curCell.Cell.Row,
        curCell.Cell.Column, curCell.Cell.Value);
}

How to upload & Save Files with Desired name

 <html>
<head>
<title>PHP Reanme image example</title>
</head>
<body>

<form action="fileupload.php" enctype="multipart/form-data" method="post">
Select image :
<input type="file" name="file"><br/>
Enter image name :<input type="text" name="filename"><br/>
<input type="submit" value="Upload" name="Submit1">

</form>

<?php

if(isset($_POST['Submit1']))
{ 


$extension = pathinfo($_FILES["file"]["name"], PATHINFO_EXTENSION);
$name = $_POST["filename"];

move_uploaded_file($_FILES["file"]["tmp_name"], $name.".".$extension);
echo "Old Image Name = ". $_FILES["file"]["name"]."<br/>";
echo "New Image Name = " . $name.".".$extension;

}


?>
</body>
</html>

Click [here] (https://meeraacademy.com/php-rename-image-while-image-uploading/

Difference between List, List<?>, List<T>, List<E>, and List<Object>

Let us talk about them in the context of Java history ;

  1. List:

List means it can include any Object. List was in the release before Java 5.0; Java 5.0 introduced List, for backward compatibility.

List list=new  ArrayList();
list.add(anyObject);
  1. List<?>:

? means unknown Object not any Object; the wildcard ? introduction is for solving the problem built by Generic Type; see wildcards; but this also causes another problem:

Collection<?> c = new ArrayList<String>();
c.add(new Object()); // Compile time error
  1. List< T> List< E>

Means generic Declaration at the premise of none T or E type in your project Lib.

  1. List< Object> means generic parameterization.

How to combine two byte arrays

Assuming your byteData array is biger than 32 + byteSalt.length()...you're going to it's length, not byteSalt.length. You're trying to copy from beyond the array end.

Improve subplot size/spacing with many subplots in matplotlib

import matplotlib.pyplot as plt

fig = plt.figure(figsize=(10,60))
plt.subplots_adjust( ... )

The plt.subplots_adjust method:

def subplots_adjust(*args, **kwargs):
    """
    call signature::

      subplots_adjust(left=None, bottom=None, right=None, top=None,
                      wspace=None, hspace=None)

    Tune the subplot layout via the
    :class:`matplotlib.figure.SubplotParams` mechanism.  The parameter
    meanings (and suggested defaults) are::

      left  = 0.125  # the left side of the subplots of the figure
      right = 0.9    # the right side of the subplots of the figure
      bottom = 0.1   # the bottom of the subplots of the figure
      top = 0.9      # the top of the subplots of the figure
      wspace = 0.2   # the amount of width reserved for blank space between subplots
      hspace = 0.2   # the amount of height reserved for white space between subplots

    The actual defaults are controlled by the rc file
    """
    fig = gcf()
    fig.subplots_adjust(*args, **kwargs)
    draw_if_interactive()

or

fig = plt.figure(figsize=(10,60))
fig.subplots_adjust( ... )

The size of the picture matters.

"I've tried messing with hspace, but increasing it only seems to make all of the graphs smaller without resolving the overlap problem."

Thus to make more white space and keep the sub plot size the total image needs to be bigger.

How to subtract X day from a Date object in Java?

@JigarJoshi it's the good answer, and of course also @Tim recommendation to use .joda-time.

I only want to add more possibilities to subtract days from a java.util.Date.

Apache-commons

One possibility is to use apache-commons-lang. You can do it using DateUtils as follows:

Date dateBefore30Days = DateUtils.addDays(new Date(),-30);

Of course add the commons-lang dependency to do only date subtract it's probably not a good options, however if you're already using commons-lang it's a good choice. There is also convenient methods to addYears,addMonths,addWeeks and so on, take a look at the api here.

Java 8

Another possibility is to take advantage of new LocalDate from Java 8 using minusDays(long days) method:

LocalDate dateBefore30Days = LocalDate.now(ZoneId.of("Europe/Paris")).minusDays(30);

How to make background of table cell transparent

You are giving colour to the background and then expecting it to be transparent? Remove background-color: #D8F0DA,

If you want #D8F0DA to be the colour of text, use color: #D8F0DA

Installing R on Mac - Warning messages: Setting LC_CTYPE failed, using "C"

Tks Ramon Gil Moreno. Pasting in Terminal and then restarting R Studio did the trick:
write org.rstudio.RStudio force.LANG en_US.UTF-8

Environment: MAC OS High Sierra 10.13.1 // RStudio version 3.4.2 (2017-09-28) -- "Short Summer"

Ennio De Leon

How to Delete node_modules - Deep Nested Folder in Windows

  1. npm install -g remove-node-modules
  2. cd to root and remove-node-modules
  3. or remove-node-modules path/to/folder

Source:

https://github.com/j-quelly/node-cleanup