SyntaxFix

Programs & Examples On #Application cache

The Application Cache (or AppCache), part of HTML5, allows a developer to specify which files the web browser should cache and make available to offline users. Your app will load and work correctly, even if the user presses the refresh button while they're offline.

Expand and collapse with angular js

In html

button ng-click="myMethod()">Videos</button>

In angular

 $scope.myMethod = function () {
         $(".collapse").collapse('hide');    //if you want to hide
         $(".collapse").collapse('toggle');  //if you want toggle
         $(".collapse").collapse('show');    //if you want to show
}

jQuery set radio button

You can simply use:

$("input[name='cols']").click();

SQLSTATE[42000]: Syntax error or access violation: 1064 You have an error in your SQL syntax — PHP — PDO

from is a keyword in SQL. You may not used it as a column name without quoting it. In MySQL, things like column names are quoted using backticks, i.e. `from`.

Personally, I wouldn't bother; I'd just rename the column.

PS. as pointed out in the comments, to is another SQL keyword so it needs to be quoted, too. Conveniently, the folks at drupal.org maintain a list of reserved words in SQL.

What is this date format? 2011-08-12T20:17:46.384Z

@John-Skeet gave me the clue to fix my own issue around this. As a younger programmer this small issue is easy to miss and hard to diagnose. So Im sharing it in the hopes it will help someone.

My issue was that I wanted to parse the following string contraining a time stamp from a JSON I have no influence over and put it in more useful variables. But I kept getting errors.

So given the following (pay attention to the string parameter inside ofPattern(); 

String str = "20190927T182730.000Z"

LocalDateTime fin;
fin = LocalDateTime.parse( str, DateTimeFormatter.ofPattern("yyyyMMdd'T'HHmmss.SSSZ") );

Error:

Exception in thread "main" java.time.format.DateTimeParseException: Text 
'20190927T182730.000Z' could not be parsed at index 19

The problem? The Z at the end of the Pattern needs to be wrapped in 'Z' just like the 'T' is. Change "yyyyMMdd'T'HHmmss.SSSZ" to "yyyyMMdd'T'HHmmss.SSS'Z'" and it works.

Removing the Z from the pattern alltogether also led to errors.

Frankly, I'd expect a Java class to have anticipated this.

What's a good, free serial port monitor for reverse-engineering?

I've been down this road and eventually opted for a hardware data scope that does non-instrusive in-line monitoring. The software solutions that I tried didn't work for me. If you had a spare PC you could probably build one, albeit rather bulky. This software data scope may work, as might this, but I haven't tried either.

Failed to start mongod.service: Unit mongod.service not found

The following steps helped me solve the problem of not being able to start mongodb on Ubuntu Server 18.04 LTS

Step 1: First, remove MongoDB from previous if installed:

sudo apt remove --autoremove mongodb-org

Step 2: Remove any mongodb repo list files: 

sudo rm /etc/apt/sources.list.d/mongodb*.list
sudo apt update

Step 3: Import the public key used by the package management system:

sudo apt-key adv --keyserver hkp://keyserver.ubuntu.com:80 --recv 9DA31620334BD75D9DCB49F368818C72E52529D4

Step 4: Create a list file for MongoDB:

echo "deb [ arch=amd64 ] https://repo.mongodb.org/apt/ubuntu bionic/mongodb-org/4.0 multiverse" | sudo tee /etc/apt/sources.list.d/mongodb-org-4.0.list

Step 5: Reload local package database:

sudo apt-get update

Step 6: Install the MongoDB packages:

sudo apt-get install -y mongodb-org

Step 7: Start MongoDB:

sudo service mongod start

Step 8: Begin using MongoDB:

mongo

Hope it helps you.

What is the difference between <html lang="en"> and <html lang="en-US">?

XML Schema requires that the xml namespace be declared and imported before using xml:lang (and other xml namespace values) RELAX NG predeclares the xml namespace, as in XML, so no additional declaration is needed.

How to convert a HTMLElement to a string

Suppose your element is entire [object HTMLDocument]. You can convert it to a String this way:

_x000D_
_x000D_ 
const htmlTemplate = `<!DOCTYPE html><html lang="en"><head></head><body></body></html>`;

const domparser = new DOMParser();
const doc = domparser.parseFromString(htmlTemplate, "text/html"); // [object HTMLDocument]

const doctype = '<!DOCTYPE html>';
const html = doc.documentElement.outerHTML;

console.log(doctype + html);
_x000D_
_x000D_
_x000D_

Efficient evaluation of a function at every cell of a NumPy array

If you are working with numbers and f(A(i,j)) = f(A(j,i)), you could use scipy.spatial.distance.cdist defining f as a distance between A(i) and A(j).

How to properly express JPQL "join fetch" with "where" clause as JPA 2 CriteriaQuery?

In JPQL the same is actually true in the spec. The JPA spec does not allow an alias to be given to a fetch join. The issue is that you can easily shoot yourself in the foot with this by restricting the context of the join fetch. It is safer to join twice.

This is normally more an issue with ToMany than ToOnes. For example, 

Select e from Employee e 
join fetch e.phones p 
where p.areaCode = '613'

This will incorrectly return all Employees that contain numbers in the '613' area code but will left out phone numbers of other areas in the returned list. This means that an employee that had a phone in the 613 and 416 area codes will loose the 416 phone number, so the object will be corrupted.

Granted, if you know what you are doing, the extra join is not desirable, some JPA providers may allow aliasing the join fetch, and may allow casting the Criteria Fetch to a Join.

SQL Server: combining multiple rows into one row

I believe for databases which support listagg function, you can do:

select id, issue, customfield, parentkey, listagg(stingvalue, ',') within group (order by id)
from jira.customfieldvalue
where customfield = 12534 and issue = 19602
group by id, issue, customfield, parentkey

git replace local version with remote version

My understanding is that, for example, you wrongly saved a file you had updated for testing purposes only. Then, when you run "git status" the file appears as "Modified" and you say some bad words. You just want the old version back and continue to work normally.

In that scenario you can just run the following command:

git checkout -- path/filename

Flexbox: how to get divs to fill up 100% of the container width without wrapping?

You can use the shorthand flex property and set it to

flex: 0 0 100%;

That's flex-grow, flex-shrink, and flex-basis in one line. Flex shrink was described above, flex grow is the opposite, and flex basis is the size of the container.

How to make canvas responsive

 
<div class="outer">
 <canvas id="canvas"></canvas>
</div>    

.outer {
 position: relative;
 width: 100%;
 padding-bottom: 100%;
}

#canvas {
 position: absolute;
 width: 100%;
 height: 100%;
}

Completely remove MariaDB or MySQL from CentOS 7 or RHEL 7

To update and answer the question without breaking mail servers. Later versions of CentOS 7 have MariaDB included as the base along with PostFix which relies on MariaDB. Removing using yum will also remove postfix and perl-DBD-MySQL. To get around this and keep postfix in place, first make a copy of /usr/lib64/libmysqlclient.so.18 (which is what postfix depends on) and then use:

rpm -qa | grep mariadb

then remove the mariadb packages using (changing to your versions):

rpm -e --nodeps "mariadb-libs-5.5.56-2.el7.x86_64"
rpm -e --nodeps "mariadb-server-5.5.56-2.el7.x86_64"
rpm -e --nodeps "mariadb-5.5.56-2.el7.x86_64"

Delete left over files and folders (which also removes any databases):

rm -f /var/log/mariadb
rm -f /var/log/mariadb/mariadb.log.rpmsave
rm -rf /var/lib/mysql
rm -rf /usr/lib64/mysql
rm -rf /usr/share/mysql

Put back the copy of /usr/lib64/libmysqlclient.so.18 you made at the start and you can restart postfix.

There is more detail at https://code.trev.id.au/centos-7-remove-mariadb-replace-mysql/ which describes how to replace mariaDB with MySQL

reading from app.config file

Also add the key "StartingMonthColumn" in App.config that you run application from, for example in the App.config of the test project.

What is the perfect counterpart in Python for "while not EOF"

The Python idiom for opening a file and reading it line-by-line is:

with open('filename') as f:
    for line in f:
        do_something(line)

The file will be automatically closed at the end of the above code (the with construct takes care of that).

Finally, it is worth noting that line will preserve the trailing newline. This can be easily removed using:

line = line.rstrip()

How to make a shape with left-top round rounded corner and left-bottom rounded corner?

try this

<?xml version="1.0" encoding="utf-8"?>
<shape xmlns:android="http://schemas.android.com/apk/res/android">
<solid android:color="@color/upkia"/>
<corners android:radius="10dp"
    android:topRightRadius="0dp"
    android:bottomRightRadius="0dp" />
</shape>

The R %in% operator

You can use all

> all(1:6 %in% 0:36)
[1] TRUE
> all(1:60 %in% 0:36)
[1] FALSE

On a similar note, if you want to check whether any of the elements is TRUE you can use any

> any(1:6 %in% 0:36)
[1] TRUE
> any(1:60 %in% 0:36)
[1] TRUE
> any(50:60 %in% 0:36)
[1] FALSE

Select row on click react-table

if u want to have multiple selection on select row..

import React from 'react';
import ReactTable from 'react-table';
import 'react-table/react-table.css';
import { ReactTableDefaults } from 'react-table';
import matchSorter from 'match-sorter';


class ThreatReportTable extends React.Component{

constructor(props){
  super(props);

  this.state = {
    selected: [],
    row: []
  }
}
render(){

  const columns = this.props.label;

  const data = this.props.data;

  Object.assign(ReactTableDefaults, {
    defaultPageSize: 10,
    pageText: false,
    previousText: '<',
    nextText: '>',
    showPageJump: false,
    showPagination: true,
    defaultSortMethod: (a, b, desc) => {
    return b - a;
  },


  })

    return(
    <ReactTable className='threatReportTable'
        data= {data}
        columns={columns}
        getTrProps={(state, rowInfo, column) => {


        return {
          onClick: (e) => {


            var a = this.state.selected.indexOf(rowInfo.index);


            if (a == -1) {
              // this.setState({selected: array.concat(this.state.selected, [rowInfo.index])});
              this.setState({selected: [...this.state.selected, rowInfo.index]});
              // Pass props to the React component

            }

            var array = this.state.selected;

            if(a != -1){
              array.splice(a, 1);
              this.setState({selected: array});


            }
          },
          // #393740 - Lighter, selected row
          // #302f36 - Darker, not selected row
          style: {background: this.state.selected.indexOf(rowInfo.index) != -1 ? '#393740': '#302f36'},


        }


        }}
        noDataText = "No available threats"
        />

    )
}
}


  export default ThreatReportTable;

I need to convert an int variable to double

I think you should casting variable or use Integer class by call out method doubleValue().

How to make java delay for a few seconds?

Java:

For calculating times we use this method:

import java.text.SimpleDateFormat;
import java.util.Calendar;


    public static String getCurrentTime() {
    Calendar cal = Calendar.getInstance();
    SimpleDateFormat sdf = new SimpleDateFormat("HH:mm:ss");
    return sdf.format(cal.getTime());
}

Second: 

import java.util.concurrent.TimeUnit;

System.out.println("Start delay of 10 seconds, Time is: " + getCurrentTime());
TimeUnit.SECONDS.sleep(10);
System.out.println("And delay of 10 seconds, Time is: " + getCurrentTime());

Output:

Start delay of 10 seconds, Time is: 14:19:08

And delay of 10 seconds, Time is: 14:19:18

Minutes:

import java.util.concurrent.TimeUnit;

System.out.println("Start delay of 1 Minute, Time is: " + getCurrentTime());
TimeUnit.MINUTES.sleep(1);
System.out.println("And delay of 1 Minute, Time is: " + getCurrentTime());

Output:

Start delay of 1 Minute, Time is: 14:21:20

And delay of 1 Minute, Time is: 14:22:20

Milliseconds:

import java.util.concurrent.TimeUnit;

System.out.println("Start delay of 2000 milliseconds, Time is: " +getCurrentTime());
TimeUnit.MILLISECONDS.sleep(2000);
System.out.println("And delay of 2000 milliseconds, Time is: " + getCurrentTime());

Output:

Start delay of 2000 milliseconds, Time is: 14:23:44

And delay of 2000 milliseconds, Time is: 14:23:46

Or:

Thread.sleep(1000); //milliseconds

ASP.NET Core Web API exception handling

The well-accepted answer helped me a lot but I wanted to pass HttpStatusCode in my middleware to manage error status code at runtime.

According to this link I got some idea to do the same. So I merged the Andrei Answer with this. So my final code is below:


1. Base class

public class ErrorDetails
{
    public int StatusCode { get; set; }
    public string Message { get; set; }

    public override string ToString()
    {
        return JsonConvert.SerializeObject(this);
    }
}


2. Custom Exception Class Type

public class HttpStatusCodeException : Exception
{
    public HttpStatusCode StatusCode { get; set; }
    public string ContentType { get; set; } = @"text/plain";

    public HttpStatusCodeException(HttpStatusCode statusCode)
    {
        this.StatusCode = statusCode;
    }

    public HttpStatusCodeException(HttpStatusCode statusCode, string message) 
        : base(message)
    {
        this.StatusCode = statusCode;
    }

    public HttpStatusCodeException(HttpStatusCode statusCode, Exception inner) 
        : this(statusCode, inner.ToString()) { }

    public HttpStatusCodeException(HttpStatusCode statusCode, JObject errorObject) 
        : this(statusCode, errorObject.ToString())
    {
        this.ContentType = @"application/json";
    }

}


3. Custom Exception Middleware

public class CustomExceptionMiddleware
{
    private readonly RequestDelegate next;

    public CustomExceptionMiddleware(RequestDelegate next)
    {
        this.next = next;
    }

    public async Task Invoke(HttpContext context /* other dependencies */)
    {
        try
        {
            await next(context);
        }
        catch (HttpStatusCodeException ex)
        {
            await HandleExceptionAsync(context, ex);
        }
        catch (Exception exceptionObj)
        {
            await HandleExceptionAsync(context, exceptionObj);
        }
    }

    private Task HandleExceptionAsync(HttpContext context, HttpStatusCodeException exception)
    {
        string result = null;
        context.Response.ContentType = "application/json";
        if (exception is HttpStatusCodeException)
        {
            result = new ErrorDetails() 
            {
                Message = exception.Message,
                StatusCode = (int)exception.StatusCode 
            }.ToString();
            context.Response.StatusCode = (int)exception.StatusCode;
        }
        else
        {
            result = new ErrorDetails() 
            { 
                Message = "Runtime Error",
                StatusCode = (int)HttpStatusCode.BadRequest
            }.ToString();
            context.Response.StatusCode = (int)HttpStatusCode.BadRequest;
        }
        return context.Response.WriteAsync(result);
    }

    private Task HandleExceptionAsync(HttpContext context, Exception exception)
    {
        string result = new ErrorDetails() 
        { 
            Message = exception.Message,
            StatusCode = (int)HttpStatusCode.InternalServerError 
        }.ToString();
        context.Response.StatusCode = (int)HttpStatusCode.BadRequest;
        return context.Response.WriteAsync(result);
    }
}


4. Extension Method

public static void ConfigureCustomExceptionMiddleware(this IApplicationBuilder app)
{
    app.UseMiddleware<CustomExceptionMiddleware>();
}

5. Configure Method in startup.cs

app.ConfigureCustomExceptionMiddleware();
app.UseMvc();

Now my login method in Account controller :

try
{
    IRepository<UserMaster> obj 
        = new Repository<UserMaster>(_objHeaderCapture, Constants.Tables.UserMaster);
    var result = obj.Get()
        .AsQueryable()
        .Where(sb => sb.EmailId.ToLower() == objData.UserName.ToLower() 
            && sb.Password == objData.Password.ToEncrypt() 
            && sb.Status == (int)StatusType.Active)
        .FirstOrDefault();
    if (result != null)//User Found
        return result;
    else // Not Found
        throw new HttpStatusCodeException(HttpStatusCode.NotFound,
            "Please check username or password");
}
catch (Exception ex)
{
    throw ex;
}

Above you can see if i have not found the user then raising the HttpStatusCodeException in which i have passed HttpStatusCode.NotFound status and a custom message
In middleware

catch (HttpStatusCodeException ex)

blocked will be called which will pass control to

private Task HandleExceptionAsync(HttpContext context, HttpStatusCodeException exception) method


But what if i got runtime error before? For that i have used try catch block which throw exception and will be catched in catch (Exception exceptionObj) block and will pass control to

Task HandleExceptionAsync(HttpContext context, Exception exception)

method.

I have used a single ErrorDetails class for uniformity.

Input and output numpy arrays to h5py

A cleaner way to handle file open/close and avoid memory leaks:

Prep: 

import numpy as np
import h5py

data_to_write = np.random.random(size=(100,20)) # or some such

Write: 

with h5py.File('name-of-file.h5', 'w') as hf:
    hf.create_dataset("name-of-dataset",  data=data_to_write)

Read: 

with h5py.File('name-of-file.h5', 'r') as hf:
    data = hf['name-of-dataset'][:]

JFrame Exit on close Java

If you don't extend JFrame and use JFrame itself in variable, you can use:

frame.dispose();
System.exit(0);

PLS-00428: an INTO clause is expected in this SELECT statement

In PLSQL block, columns of select statements must be assigned to variables, which is not the case in SQL statements.

The second BEGIN's SQL statement doesn't have INTO clause and that caused the error.

DECLARE
   PROD_ROW_ID   VARCHAR (10) := NULL;
   VIS_ROW_ID    NUMBER;
   DSC           VARCHAR (512);
BEGIN
   SELECT ROW_ID
     INTO VIS_ROW_ID
     FROM SIEBEL.S_PROD_INT
    WHERE PART_NUM = 'S0146404';

   BEGIN
      SELECT    RTRIM (VIS.SERIAL_NUM)
             || ','
             || RTRIM (PLANID.DESC_TEXT)
             || ','
             || CASE
                   WHEN PLANID.HIGH = 'TEST123'
                   THEN
                      CASE
                         WHEN TO_DATE (PROD.START_DATE) + 30 > SYSDATE
                         THEN
                            'Y'
                         ELSE
                            'N'
                      END
                   ELSE
                      'N'
                END
             || ','
             || 'GB'
             || ','
             || RTRIM (TO_CHAR (PROD.START_DATE, 'YYYY-MM-DD'))
        INTO DSC
        FROM SIEBEL.S_LST_OF_VAL PLANID
             INNER JOIN SIEBEL.S_PROD_INT PROD
                ON PROD.PART_NUM = PLANID.VAL
             INNER JOIN SIEBEL.S_ASSET NETFLIX
                ON PROD.PROD_ID = PROD.ROW_ID
             INNER JOIN SIEBEL.S_ASSET VIS
                ON VIS.PROM_INTEG_ID = PROD.PROM_INTEG_ID
             INNER JOIN SIEBEL.S_PROD_INT VISPROD
                ON VIS.PROD_ID = VISPROD.ROW_ID
       WHERE     PLANID.TYPE = 'Test Plan'
             AND PLANID.ACTIVE_FLG = 'Y'
             AND VISPROD.PART_NUM = VIS_ROW_ID
             AND PROD.STATUS_CD = 'Active'
             AND VIS.SERIAL_NUM IS NOT NULL;
   END;
END;
/

References

http://docs.oracle.com/cd/E11882_01/appdev.112/e25519/static.htm#LNPLS00601 http://docs.oracle.com/cd/B19306_01/appdev.102/b14261/selectinto_statement.htm#CJAJAAIG http://pls-00428.ora-code.com/

onchange equivalent in angular2

In Angular you can define event listeners like in the example below:

<!-- Here you can call public methods from parental component -->
<input (change)="method_name()">

Failed to authenticate on SMTP server error using gmail

I had the same problem and I've already tried everything and nothing seemed to work until I just changed the 'host' value in config.php to:

 'host' => env('smtp.mailtrap.io'),

When I changed that it worked nicely, somehow it was using the default host " smtp.mailtrap.org" and ignoring the .env variable I was setting.

After making some test I realize that if I placed the env variable in this order it would worked as it shoulded:

MAIL_HOST=smtp.mailtrap.io

?MAIL_DRIVER=smtp

?MAIL_PORT=2525?

MAIL_USERNAME=xxxx

?MAIL_PASSWORD=xxx

?MAIL_ENCRYPTION=null

How do I concatenate const/literal strings in C?

Also malloc and realloc are useful if you don't know ahead of time how many strings are being concatenated.

#include <stdio.h>
#include <string.h>

void example(const char *header, const char **words, size_t num_words)
{
    size_t message_len = strlen(header) + 1; /* + 1 for terminating NULL */
    char *message = (char*) malloc(message_len);
    strncat(message, header, message_len);

    for(int i = 0; i < num_words; ++i)
    {
       message_len += 1 + strlen(words[i]); /* 1 + for separator ';' */
       message = (char*) realloc(message, message_len);
       strncat(strncat(message, ";", message_len), words[i], message_len);
    }

    puts(message);

    free(message);
}

INNER JOIN in UPDATE sql for DB2

You don't say what platform you're targeting. Referring to tables as files, though, leads me to believe that you're NOT running DB2 on Linux, UNIX or Windows (LUW).

However, if you are on DB2 LUW, see the MERGE statement:

For your example statement, this would be written as:

merge into file1 a
   using (select anotherfield, something from file2) b
   on substr(a.firstfield,10,20) = substr(b.anotherfield,1,10)
when matched and a.firstfield like 'BLAH%'
   then update set a.firstfield = 'BIT OF TEXT' || b.something;

Please note: For DB2, the third argument of the SUBSTR function is the number of bytes to return, not the ending position. Therefore, SUBSTR(a.firstfield,10,20) returns CHAR(20). However, SUBSTR(b.anotherfield,1,10) returns CHAR(10). I'm not sure if this was done on purpose, but it may affect your comparison.

How to set the value of a hidden field from a controller in mvc

You need to write following code on controller suppose test is model, and Name, Address are field of this model.

public ActionResult MyMethod()
{
    Test test=new Test();
    var test.Name="John";
    return View(test);   
}

now use like like this on your view to give set value of hidden variable.

@model YourApplicationName.Model.Test

@Html.HiddenFor(m=>m.Name,new{id="hdnFlag"})

This will automatically set hidden value=john.

Oracle 11g Express Edition for Windows 64bit?

There is no Windows 64-bit version of Oracle Express Edition. You'll have to go for Standard/Enterprise editions.

Wordpress 403/404 Errors: You don't have permission to access /wp-admin/themes.php on this server

A few years late, but I have a solution for the most recent version of WordPress, which has this same issue (WordPress-generated .htaccess files break sites, reuslting in 403 Forbidden error messages). Here's that it looks like when WordPress creates it:

# BEGIN WordPress
<IfModule mod_rewrite.c>
RewriteEngine On
RewriteBase /
RewriteRule ^index\.php$ - [L]
RewriteCond %{REQUEST_FILENAME} !-f
RewriteCond %{REQUEST_FILENAME} !-d
RewriteRule . /index.php [L]
</IfModule>

# END WordPress

The problem is that the conditional doesn't work. It doesn't work because the module it's looking for isn't .c, it's .so. I think this is a platform-specific, or configuration-specific issue, where Mac OS and Lunix Apache installations are set up for .so AKA 'shared-object' modules. Looking for a .c module shouldn't break the conditional, I think that's a bug, but it's the issue.

Simply change the mod_rewrite.c to mod_rewrite.so and you're all set to go!

# BEGIN WordPress
<IfModule mod_rewrite.so>
RewriteEngine On
RewriteBase /
RewriteRule ^index\.php$ - [L]
RewriteCond %{REQUEST_FILENAME} !-f
RewriteCond %{REQUEST_FILENAME} !-d
RewriteRule . /index.php [L]
</IfModule>

# END WordPress

How to view the roles and permissions granted to any database user in Azure SQL server instance?

Per the MSDN documentation for sys.database_permissions, this query lists all permissions explicitly granted or denied to principals in the database you're connected to:

SELECT DISTINCT pr.principal_id, pr.name, pr.type_desc, 
    pr.authentication_type_desc, pe.state_desc, pe.permission_name
FROM sys.database_principals AS pr
JOIN sys.database_permissions AS pe
    ON pe.grantee_principal_id = pr.principal_id;

Per Managing Databases and Logins in Azure SQL Database, the loginmanager and dbmanager roles are the two server-level security roles available in Azure SQL Database. The loginmanager role has permission to create logins, and the dbmanager role has permission to create databases. You can view which users belong to these roles by using the query you have above against the master database. You can also determine the role memberships of users on each of your user databases by using the same query (minus the filter predicate) while connected to them.

Find mouse position relative to element

For those of you developing regular websites or PWAs (Progressive Web Apps) for mobile devices and/or laptops/monitors with touch screens, then you have landed here because you might be used to mouse events and are new to the sometimes painful experience of Touch events... yay!

There are just 3 rules:

  1. Do as little as possible during mousemove or touchmove events.
  2. Do as much as possible during mousedown or touchstart events.
  3. Cancel propagation and prevent defaults for touch events to prevent mouse events from also firing on hybrid devices.

Needless to say, things are more complicated with touch events because there can be more than one and they're more flexible (complicated) than mouse events. I'm only going to cover a single touch here. Yes, I'm being lazy, but it's the most common type of touch, so there.

_x000D_
_x000D_ 
var posTop;_x000D_
var posLeft;_x000D_
function handleMouseDown(evt) {_x000D_
  var e = evt || window.event; // Because Firefox, etc._x000D_
  posTop = e.target.offsetTop;_x000D_
  posLeft = e.target.offsetLeft;_x000D_
  e.target.style.background = "red";_x000D_
  // The statement above would be better handled by CSS_x000D_
  // but it's just an example of a generic visible indicator._x000D_
}_x000D_
function handleMouseMove(evt) {_x000D_
  var e = evt || window.event;_x000D_
  var x = e.offsetX; // Wonderfully_x000D_
  var y = e.offsetY; // Simple!_x000D_
  e.target.innerHTML = "Mouse: " + x + ", " + y;_x000D_
  if (posTop)_x000D_
    e.target.innerHTML += "<br>" + (x + posLeft) + ", " + (y + posTop);_x000D_
}_x000D_
function handleMouseOut(evt) {_x000D_
  var e = evt || window.event;_x000D_
  e.target.innerHTML = "";_x000D_
}_x000D_
function handleMouseUp(evt) {_x000D_
  var e = evt || window.event;_x000D_
  e.target.style.background = "yellow";_x000D_
}_x000D_
function handleTouchStart(evt) {_x000D_
  var e = evt || window.event;_x000D_
  var rect = e.target.getBoundingClientRect();_x000D_
  posTop = rect.top;_x000D_
  posLeft = rect.left;_x000D_
  e.target.style.background = "green";_x000D_
  e.preventDefault(); // Unnecessary if using Vue.js_x000D_
  e.stopPropagation(); // Same deal here_x000D_
}_x000D_
function handleTouchMove(evt) {_x000D_
  var e = evt || window.event;_x000D_
  var pageX = e.touches[0].clientX; // Touches are page-relative_x000D_
  var pageY = e.touches[0].clientY; // not target-relative_x000D_
  var x = pageX - posLeft;_x000D_
  var y = pageY - posTop;_x000D_
  e.target.innerHTML = "Touch: " + x + ", " + y;_x000D_
  e.target.innerHTML += "<br>" + pageX + ", " + pageY;_x000D_
  e.preventDefault();_x000D_
  e.stopPropagation();_x000D_
}_x000D_
function handleTouchEnd(evt) {_x000D_
  var e = evt || window.event;_x000D_
  e.target.style.background = "yellow";_x000D_
  // Yes, I'm being lazy and doing the same as mouseout here_x000D_
  // but obviously you could do something different if needed._x000D_
  e.preventDefault();_x000D_
  e.stopPropagation();_x000D_
}
_x000D_ 
div {_x000D_
  background: yellow;_x000D_
  height: 100px;_x000D_
  left: 50px;_x000D_
  position: absolute;_x000D_
  top: 80px;_x000D_
  user-select: none; /* Disable text selection */_x000D_
  -ms-user-select: none;_x000D_
  width: 100px;_x000D_
}
_x000D_ 
<div _x000D_
  onmousedown="handleMouseDown()" _x000D_
  onmousemove="handleMouseMove()"_x000D_
  onmouseout="handleMouseOut()"_x000D_
  onmouseup="handleMouseUp()" _x000D_
  ontouchstart="handleTouchStart()" _x000D_
  ontouchmove="handleTouchMove()" _x000D_
  ontouchend="handleTouchEnd()">_x000D_
</div>_x000D_
Move over box for coordinates relative to top left of box.<br>_x000D_
Hold mouse down or touch to change color.<br>_x000D_
Drag to turn on coordinates relative to top left of page.
_x000D_
_x000D_
_x000D_

Prefer using Vue.js? I do! Then your HTML would look like this:

<div @mousedown="handleMouseDown"
     @mousemove="handleMouseMove"
     @mouseup="handleMouseUp"
     @touchstart.stop.prevent="handleTouchStart"
     @touchmove.stop.prevent="handleTouchMove"
     @touchend.stop.prevent="handleTouchEnd">

How to solve Permission denied (publickey) error when using Git?

I had to copy my ssh keys to the root folder. Google Cloud Compute Engine running Ubuntu 18.04

sudo cp ~/.ssh/* /root/.ssh/

What was the strangest coding standard rule that you were forced to follow?

Applying s_ to variables and methods which were deemed "safety critical" for software that was part of a control system. Couple this with the other rule about putting m_ on the front of member variables and you'd get something ridiculous like "s_m_blah()", which is darn annoying to write and not very readable in my opinion. In the end some 'safety expert' was supposed to gain insight by looking at the code and determining something from it by using those "s_" - in practice, they didn't know c++ too well so they couldn't do much other than make reports on the number of identifiers that we'd marked as 'safety critical'. Utter nonsense...

Run PowerShell scripts on remote PC

After further investigating on PSExec tool, I think I got the answer. I need to add -i option to tell PSExec to launch process on remote in interactive mode:

PSExec \\RPC001 -i -u myID -p myPWD PowerShell C:\script\StartPS.ps1 par1 par2

Without -i, powershell.exe is running on the remote in waiting mode. Interesting point is that if I run a simple bat (without PS in bat), it works fine. Maybe this is something special for PS case? Welcome comments and explanations.

What is the standard way to add N seconds to datetime.time in Python?

Thanks to @Pax Diablo, @bvmou and @Arachnid for the suggestion of using full datetimes throughout. If I have to accept datetime.time objects from an external source, then this seems to be an alternative add_secs_to_time() function:

def add_secs_to_time(timeval, secs_to_add):
    dummy_date = datetime.date(1, 1, 1)
    full_datetime = datetime.datetime.combine(dummy_date, timeval)
    added_datetime = full_datetime + datetime.timedelta(seconds=secs_to_add)
    return added_datetime.time()

This verbose code can be compressed to this one-liner:

(datetime.datetime.combine(datetime.date(1, 1, 1), timeval) + datetime.timedelta(seconds=secs_to_add)).time()

but I think I'd want to wrap that up in a function for code clarity anyway.

Can't connect to local MySQL server through socket '/var/mysql/mysql.sock' (38)

are you sure you installed mysql as well as mysql server..

For example to install mySql server I'll use yum or apt to install both mysql command line tool and the server:

yum -y install mysql mysql-server (or apt-get install mysql mysql-server)

Enable the MySQL service:

/sbin/chkconfig mysqld on

Start the MySQL server:

/sbin/service mysqld start

afterwards set the MySQL root password:

mysqladmin -u root password 'new-password' (with the quotes)

I hope it helps.

How do I get the HTML code of a web page in PHP?

you can use the DomDocument method to get an individual HTML tag level variable too 

$homepage = file_get_contents('https://www.example.com/');
$doc = new DOMDocument;
$doc->loadHTML($homepage);
$titles = $doc->getElementsByTagName('h3');
echo $titles->item(0)->nodeValue;

Node.js - Maximum call stack size exceeded

Regarding increasing the max stack size, on 32 bit and 64 bit machines V8's memory allocation defaults are, respectively, 700 MB and 1400 MB. In newer versions of V8, memory limits on 64 bit systems are no longer set by V8, theoretically indicating no limit. However, the OS (Operating System) on which Node is running can always limit the amount of memory V8 can take, so the true limit of any given process cannot be generally stated.

Though V8 makes available the --max_old_space_size option, which allows control over the amount of memory available to a process, accepting a value in MB. Should you need to increase memory allocation, simply pass this option the desired value when spawning a Node process.

It is often an excellent strategy to reduce the available memory allocation for a given Node instance, especially when running many instances. As with stack limits, consider whether massive memory needs are better delegated to a dedicated storage layer, such as an in-memory database or similar.

'module' object has no attribute 'DataFrame'

I recieved a similar error:

AttributeError: module 'pandas' has no attribute 'DataFrame'

The cause of my error was that I ran pip install of pandas as root, and my user did not have permission to the directory.

My fix was to run:

sudo chmod -R 755 /usr/local/lib/python3.6/site-packages

Docker "ERROR: could not find an available, non-overlapping IPv4 address pool among the defaults to assign to the network"

This happened to me because I was using OpenVPN. I found a way that I don't need to stop using the VPN or manually add a network to the docker-compose file nor run any crazy script.

I switched to WireGuard instead of OpenVPN. More specifically, as I am running the nordvpn solution, I installed WireGuard and used their version of it, NordLynx.

How to cache Google map tiles for offline usage?

On http://www.google.com/earth/media/licensing.html there is a "Mobile" section containing :

Similar to our online terms, if you use our APIs or a mobile device’s native Google Maps implementation (such as on an Android-powered phone or iPhone), no special permission is required, but you must always keep the Google name visible. Offline caching of our content is never allowed.

How Should I Declare Foreign Key Relationships Using Code First Entity Framework (4.1) in MVC3?

If you have an Order class, adding a property that references another class in your model, for instance Customer should be enough to let EF know there's a relationship in there:

public class Order
{
    public int ID { get; set; }

    // Some other properties

    // Foreign key to customer
    public virtual Customer Customer { get; set; }
}

You can always set the FK relation explicitly:

public class Order
{
    public int ID { get; set; }

    // Some other properties

    // Foreign key to customer
    [ForeignKey("Customer")]
    public string CustomerID { get; set; }
    public virtual Customer Customer { get; set; }
}

The ForeignKeyAttribute constructor takes a string as a parameter: if you place it on a foreign key property it represents the name of the associated navigation property. If you place it on the navigation property it represents the name of the associated foreign key.

What this means is, if you where to place the ForeignKeyAttribute on the Customer property, the attribute would take CustomerID in the constructor:

public string CustomerID { get; set; }
[ForeignKey("CustomerID")]
public virtual Customer Customer { get; set; }

EDIT based on Latest Code You get that error because of this line:

[ForeignKey("Parent")]
public Patient Patient { get; set; }

EF will look for a property called Parent to use it as the Foreign Key enforcer. You can do 2 things:

1) Remove the ForeignKeyAttribute and replace it with the RequiredAttribute to mark the relation as required:

[Required]
public virtual Patient Patient { get; set; }

Decorating a property with the RequiredAttribute also has a nice side effect: The relation in the database is created with ON DELETE CASCADE.

I would also recommend making the property virtual to enable Lazy Loading.

2) Create a property called Parent that will serve as a Foreign Key. In that case it probably makes more sense to call it for instance ParentID (you'll need to change the name in the ForeignKeyAttribute as well):

public int ParentID { get; set; }

In my experience in this case though it works better to have it the other way around:

[ForeignKey("Patient")]
public int ParentID { get; set; }

public virtual Patient Patient { get; set; }

Git Cherry-pick vs Merge Workflow

In my opinion cherry-picking should be reserved for rare situations where it is required, for example if you did some fix on directly on 'master' branch (trunk, main development branch) and then realized that it should be applied also to 'maint'. You should base workflow either on merge, or on rebase (or "git pull --rebase").

Please remember that cherry-picked or rebased commit is different from the point of view of Git (has different SHA-1 identifier) than the original, so it is different than the commit in remote repository. (Rebase can usually deal with this, as it checks patch id i.e. the changes, not a commit id).

Also in git you can merge many branches at once: so called octopus merge. Note that octopus merge has to succeed without conflicts. Nevertheless it might be useful.

HTH.

passing argument to DialogFragment

In my case, none of the code above with bundle-operate works; Here is my decision (I don't know if it is proper code or not, but it works in my case):

public class DialogMessageType extends DialogFragment {
    private static String bodyText;

    public static DialogMessageType addSomeString(String temp){
        DialogMessageType f = new DialogMessageType();
        bodyText = temp;
        return f;
    };

    @Override
    public Dialog onCreateDialog(Bundle savedInstanceState) {
        final String[] choiseArray = {"sms", "email"};
        String title = "Send text via:";
        final AlertDialog.Builder builder = new AlertDialog.Builder(getActivity());
        builder.setTitle(title).setItems(choiseArray, itemClickListener);
        builder.setCancelable(true);
        return builder.create();
    }

    DialogInterface.OnClickListener itemClickListener = new DialogInterface.OnClickListener() {
        @Override
        public void onClick(DialogInterface dialog, int which) {
            switch (which){
                case 0:
                    prepareToSendCoordsViaSMS(bodyText);
                    dialog.dismiss();
                    break;
                case 1:
                    prepareToSendCoordsViaEmail(bodyText);
                    dialog.dismiss();
                    break;
                default:
                    break;
            }
        }
    };
[...]
}

public class SendObjectActivity extends FragmentActivity {
[...]

DialogMessageType dialogMessageType = DialogMessageType.addSomeString(stringToSend);
dialogMessageType.show(getSupportFragmentManager(),"dialogMessageType");

[...]
}

How print out the contents of a HashMap<String, String> in ascending order based on its values?

Try:

try
{
    int cnt= m.getSmartPhoneCount("HTC",true);      
    System.out.println("total count of HTC="+cnt);
}  
catch (NoSuchBrandSmartPhoneAvailableException e)
{
    // TODO Auto-generated catch 
    e.printStackTrace();
}

Why doesn't Java offer operator overloading?

While the Java language does not directly support operator overloading, you can use the Manifold compiler plugin in any Java project to enable it. It supports Java 8 - 13 (the current Java version) and is fully supported in IntelliJ IDEA.

Difference between numpy dot() and Python 3.5+ matrix multiplication @

In mathematics, I think the dot in numpy makes more sense

dot(a,b)_{i,j,k,a,b,c} = formula

since it gives the dot product when a and b are vectors, or the matrix multiplication when a and b are matrices

As for matmul operation in numpy, it consists of parts of dot result, and it can be defined as

>matmul(a,b)_{i,j,k,c} = formula

So, you can see that matmul(a,b) returns an array with a small shape, which has smaller memory consumption and make more sense in applications. In particular, combining with broadcasting, you can get

matmul(a,b)_{i,j,k,l} = formula

for example.

From the above two definitions, you can see the requirements to use those two operations. Assume a.shape=(s1,s2,s3,s4) and b.shape=(t1,t2,t3,t4)

  • To use dot(a,b) you need

    1. t3=s4;

  • To use matmul(a,b) you need

    1. t3=s4
    2. t2=s2, or one of t2 and s2 is 1
    3. t1=s1, or one of t1 and s1 is 1

Use the following piece of code to convince yourself.

Code sample

import numpy as np
for it in xrange(10000):
    a = np.random.rand(5,6,2,4)
    b = np.random.rand(6,4,3)
    c = np.matmul(a,b)
    d = np.dot(a,b)
    #print 'c shape: ', c.shape,'d shape:', d.shape

    for i in range(5):
        for j in range(6):
            for k in range(2):
                for l in range(3):
                    if not c[i,j,k,l] == d[i,j,k,j,l]:
                        print it,i,j,k,l,c[i,j,k,l]==d[i,j,k,j,l] #you will not see them

jackson deserialization json to java-objects

It looks like you are trying to read an object from JSON that actually describes an array. Java objects are mapped to JSON objects with curly braces {} but your JSON actually starts with square brackets [] designating an array.

What you actually have is a List<product> To describe generic types, due to Java's type erasure, you must use a TypeReference. Your deserialization could read: myProduct = objectMapper.readValue(productJson, new TypeReference<List<product>>() {});

A couple of other notes: your classes should always be PascalCased. Your main method can just be public static void main(String[] args) throws Exception which saves you all the useless catch blocks.

How do I find which rpm package supplies a file I'm looking for?

You can do this alike here but with your package. In my case, it was lsb_release

Run: yum whatprovides lsb_release

Response: 

redhat-lsb-core-4.1-24.el7.i686 : LSB Core module support
Repo        : rhel-7-server-rpms
Matched from:
Filename    : /usr/bin/lsb_release

redhat-lsb-core-4.1-24.el7.x86_64 : LSB Core module support
Repo        : rhel-7-server-rpms
Matched from:
Filename    : /usr/bin/lsb_release

redhat-lsb-core-4.1-27.el7.i686 : LSB Core module support
Repo        : rhel-7-server-rpms
Matched from:
Filename    : /usr/bin/lsb_release

redhat-lsb-core-4.1-27.el7.x86_64 : LSB Core module support
Repo        : rhel-7-server-rpms
Matched from:
Filename    : /usr/bin/lsb_release`

Run to install: yum install redhat-lsb-core

The package name SHOULD be without number and system type so yum packager can choose what is best for him.

Deleting a SQL row ignoring all foreign keys and constraints

You can disable all of the constaints on your database by the following line of code:

EXEC sp_MSforeachtable "ALTER TABLE ? NOCHECK CONSTRAINT all"

and after the runing your update/delete command, you can enable it again as the following:

EXEC sp_MSforeachtable "ALTER TABLE ? WITH CHECK CHECK CONSTRAINT all"

How to override trait function and call it from the overridden function?

An alternative approach if interested - with an extra intermediate class to use the normal OOO way. This simplifies the usage with parent::methodname 

trait A {
    function calc($v) {
        return $v+1;
    }
}

// an intermediate class that just uses the trait
class IntClass {
    use A;
}

// an extended class from IntClass
class MyClass extends IntClass {
    function calc($v) {
        $v++;
        return parent::calc($v);
    }
}

How to subtract a day from a date?

Also just another nice function i like to use when i want to compute i.e. first/last day of the last month or other relative timedeltas etc. ...

The relativedelta function from dateutil function (a powerful extension to the datetime lib)

import datetime as dt
from dateutil.relativedelta import relativedelta
#get first and last day of this and last month)
today = dt.date.today()
first_day_this_month = dt.date(day=1, month=today.month, year=today.year)
last_day_last_month = first_day_this_month - relativedelta(days=1)
print (first_day_this_month, last_day_last_month)

>2015-03-01 2015-02-28

How do I load an url in iframe with Jquery

Just in case anyone still stumbles upon this old question:

The code was theoretically almost correct in a sense, the problem was the use of $('this') instead of $(this), therefore telling jQuery to look for a tag. 

$(document).ready(function(){
  $("#frame").click(function () { 
    $(this).load("http://www.google.com/");
  });
});

The script itself woudln't work as it is right now though because the load() function itself is an AJAX function, and google does not seem to specifically allow the use of loading this page with AJAX, but this method should be easy to use in order to load pages from your own domain by using relative paths.

Can you break from a Groovy "each" closure?

You can't break from a Groovy each loop, but you can break from a java "enhanced" for loop.

def a = [1, 2, 3, 4, 5, 6, 7]

for (def i : a) {
    if (i < 2)
        continue
    if (i > 5)
        break
    println i
}

Output:

2
3
4
5

This might not fit for absolutely every situation but it's helped for me :)

C# - How to get Program Files (x86) on Windows 64 bit

Note, however, that the ProgramFiles(x86) environment variable is only available if your application is running 64-bit.

If your application is running 32-bit, you can just use the ProgramFiles environment variable whose value will actually be "Program Files (x86)".

HTML span align center not working?

Just use word-wrap:break-word; in the css. It works.

Pandas dataframe fillna() only some columns in place

using the top answer produces a warning about making changes to a copy of a df slice. Assuming that you have other columns, a better way to do this is to pass a dictionary:
df.fillna({'A': 'NA', 'B': 'NA'}, inplace=True)

Safest way to run BAT file from Powershell script

@Rynant 's solution worked for me. I had a couple of additional requirements though:

  1. Don't PAUSE if encountered in bat file
  2. Optionally, append bat file output to log file

Here's what I got working (finally):

[PS script code]

& runner.bat bat_to_run.bat logfile.txt

[runner.bat]

@echo OFF

REM This script can be executed from within a powershell script so that the bat file
REM passed as %1 will not cause execution to halt if PAUSE is encountered.
REM If {logfile} is included, bat file output will be appended to logfile.
REM
REM Usage:
REM runner.bat [path of bat script to execute] {logfile}

if not [%2] == [] GOTO APPEND_OUTPUT
@echo | call %1
GOTO EXIT

:APPEND_OUTPUT
@echo | call %1  1> %2 2>&1

:EXIT

Why does the order in which libraries are linked sometimes cause errors in GCC?

The GNU ld linker is a so-called smart linker. It will keep track of the functions used by preceding static libraries, permanently tossing out those functions that are not used from its lookup tables. The result is that if you link a static library too early, then the functions in that library are no longer available to static libraries later on the link line.

The typical UNIX linker works from left to right, so put all your dependent libraries on the left, and the ones that satisfy those dependencies on the right of the link line. You may find that some libraries depend on others while at the same time other libraries depend on them. This is where it gets complicated. When it comes to circular references, fix your code!

What is the maximum number of edges in a directed graph with n nodes?

Undirected is N^2. Simple - every node has N options of edges (himself included), total of N nodes thus N*N

log4j: Log output of a specific class to a specific appender

An example:

log4j.rootLogger=ERROR, logfile

log4j.appender.logfile=org.apache.log4j.DailyRollingFileAppender
log4j.appender.logfile.datePattern='-'dd'.log'
log4j.appender.logfile.File=log/radius-prod.log
log4j.appender.logfile.layout=org.apache.log4j.PatternLayout
log4j.appender.logfile.layout.ConversionPattern=%-6r %d{ISO8601} %-5p %40.40c %x - %m\n

log4j.logger.foo.bar.Baz=DEBUG, myappender
log4j.additivity.foo.bar.Baz=false

log4j.appender.myappender=org.apache.log4j.DailyRollingFileAppender
log4j.appender.myappender.datePattern='-'dd'.log'
log4j.appender.myappender.File=log/access-ext-dmz-prod.log
log4j.appender.myappender.layout=org.apache.log4j.PatternLayout
log4j.appender.myappender.layout.ConversionPattern=%-6r %d{ISO8601} %-5p %40.40c %x - %m\n

Type converting slices of interfaces

Try interface{} instead. To cast back as slice, try

func foo(bar interface{}) {
    s := bar.([]string)
    // ...
}

Duplicating a MySQL table, indices, and data

The better way to duplicate a table is using only DDL statement. In this way, independently from the number of records in the table, you can perform the duplication instantly.

My purpose is:

DROP TABLE IF EXISTS table_name_OLD;
CREATE TABLE table_name_NEW LIKE table_name;
RENAME TABLE table_name TO table_name_OLD;
RENAME TABLE table_name _NEW TO table_name;

This avoids the INSERT AS SELECT statement that, in case of table with a lot of records can take time to be executed.

I suggest also to create a PLSQL procedure as the following example:

DELIMITER //
CREATE PROCEDURE backup_table(tbl_name varchar(255))
BEGIN
  -- DROP TABLE IF EXISTS GLS_DEVICES_OLD;
  SET @query = concat('DROP TABLE IF EXISTS ',tbl_name,'_OLD');
  PREPARE stmt FROM @query;
  EXECUTE stmt;
  DEALLOCATE PREPARE stmt;

  -- CREATE TABLE GLS_DEVICES_NEW LIKE GLS_DEVICES;
  SET @query = concat('CREATE TABLE ',tbl_name,'_NEW LIKE ',tbl_name);
  PREPARE stmt FROM @query;
  EXECUTE stmt;
  DEALLOCATE PREPARE stmt;

  -- RENAME TABLE GLS_DEVICES TO GLS_DEVICES_OLD;
  SET @query = concat('RENAME TABLE ',tbl_name,' TO ',tbl_name,'_OLD');
  PREPARE stmt FROM @query;
  EXECUTE stmt;
  DEALLOCATE PREPARE stmt;  

  --  RENAME TABLE GLS_DEVICES_NEW TO GLS_DEVICES;
  SET @query = concat('RENAME TABLE ',tbl_name,'_NEW TO ',tbl_name);
  PREPARE stmt FROM @query;
  EXECUTE stmt;
  DEALLOCATE PREPARE stmt; 
END//
DELIMITER ;

Have a nice day! Alex

Make DateTimePicker work as TimePicker only in WinForms

You want to set its 'Format' property to be time and add a spin button control to it:

yourDateTimeControl.Format = DateTimePickerFormat.Time;
yourDateTimeControl.ShowUpDown = true;

Disabling SSL Certificate Validation in Spring RestTemplate

If you are using rest template, you can use this piece of code

    fun getClientHttpRequestFactory(): ClientHttpRequestFactory {
        val timeout = envTimeout.toInt()
        val config = RequestConfig.custom()
            .setConnectTimeout(timeout)
            .setConnectionRequestTimeout(timeout)
            .setSocketTimeout(timeout)
            .build()

        val acceptingTrustStrategy = TrustStrategy { chain: Array<X509Certificate?>?, authType: String? -> true }

        val sslContext: SSLContext = SSLContexts.custom()
            .loadTrustMaterial(null, acceptingTrustStrategy)
            .build()

        val csf = SSLConnectionSocketFactory(sslContext)

        val client = HttpClientBuilder
            .create()
            .setDefaultRequestConfig(config)
            .setSSLSocketFactory(csf)
            .setSSLHostnameVerifier(NoopHostnameVerifier.INSTANCE)
            .build()
        return HttpComponentsClientHttpRequestFactory(client)
    }

    @Bean
    fun getRestTemplate(): RestTemplate {
        return RestTemplate(getClientHttpRequestFactory())
    }

How to run an EXE file in PowerShell with parameters with spaces and quotes

When PowerShell sees a command starting with a string it just evaluates the string, that is, it typically echos it to the screen, for example:

PS> "Hello World"
Hello World

If you want PowerShell to interpret the string as a command name then use the call operator (&) like so:

PS> & 'C:\Program Files\IIS\Microsoft Web Deploy\msdeploy.exe'

After that you probably only need to quote parameter/argument pairs that contain spaces and/or quotation chars. When you invoke an EXE file like this with complex command line arguments it is usually very helpful to have a tool that will show you how PowerShell sends the arguments to the EXE file. The PowerShell Community Extensions has such a tool. It is called echoargs. You just replace the EXE file with echoargs - leaving all the arguments in place, and it will show you how the EXE file will receive the arguments, for example:

PS> echoargs -verb:sync -source:dbfullsql="Data Source=mysource;Integrated Security=false;User ID=sa;Pwd=sapass!;Database=mydb;" -dest:dbfullsql="Data Source=.\mydestsource;Integrated Security=false;User ID=sa;Pwd=sapass!;Database=mydb;",computername=10.10.10.10,username=administrator,password=adminpass

Arg 0 is <-verb:sync>
Arg 1 is <-source:dbfullsql=Data>
Arg 2 is <Source=mysource;Integrated>
Arg 3 is <Security=false;User>
Arg 4 is <ID=sa;Pwd=sapass!;Database=mydb;>
Arg 5 is <-dest:dbfullsql=Data>
Arg 6 is <Source=.\mydestsource;Integrated>
Arg 7 is <Security=false;User>
Arg 8 is <ID=sa;Pwd=sapass!;Database=mydb; computername=10.10.10.10 username=administrator password=adminpass>

Using echoargs you can experiment until you get it right, for example:

PS> echoargs -verb:sync "-source:dbfullsql=Data Source=mysource;Integrated Security=false;User ID=sa;Pwd=sapass!;Database=mydb;"
Arg 0 is <-verb:sync>
Arg 1 is <-source:dbfullsql=Data Source=mysource;Integrated Security=false;User ID=sa;Pwd=sapass!;Database=mydb;>

It turns out I was trying too hard before to maintain the double quotes around the connection string. Apparently that isn't necessary because even cmd.exe will strip those out.

BTW, hats off to the PowerShell team. They were quite helpful in showing me the specific incantation of single & double quotes to get the desired result - if you needed to keep the internal double quotes in place. :-) They also realize this is an area of pain, but they are driven by the number of folks are affected by a particular issue. If this is an area of pain for you, then please vote up this PowerShell bug submission.

For more information on how PowerShell parses, check out my Effective PowerShell blog series - specifically item 10 - "Understanding PowerShell Parsing Modes"

UPDATE 4/4/2012: This situation gets much easier to handle in PowerShell V3. See this blog post for details.

Select query to remove non-numeric characters

 
 Declare @MainTable table(id int identity(1,1),TextField varchar(100))
  INSERT INTO @MainTable (TextField)
 VALUES
 ('6B32E')
 declare @i int=1
  Declare @originalWord varchar(100)=''
  WHile @i<=(Select count(*) from @MainTable)
  BEGIN
  Select @originalWord=TextField from @MainTable where id=@i

 Declare @r varchar(max) ='', @len int ,@c char(1), @x int = 0

    Select @len = len(@originalWord)
    declare @pn varchar(100)=@originalWord
    while @x <= @len 
    begin

      Select @c = SUBSTRING(@pn,@x,1)
    if(@c!='')
    BEGIN
            if ISNUMERIC(@c) = 0 and @c <> '-'
    BEGIN
     Select @r = cast(@r as varchar) + cast(replace((SELECT ASCII(@c)-64),'-','') as varchar)

   end
   ELSE
   BEGIN
    Select @r = @r + @c


   END

END


    Select @x = @x +1

    END
    Select @r
  Set @i=@i+1
  END

How to show full height background image?

You can do it with the code you have, you just need to ensure that html and body are set to 100% height.

Demo: http://jsfiddle.net/kevinPHPkevin/a7eGN/

html, body {
    height:100%;
} 

body {
    background-color: white;
    background-image: url('http://www.canvaz.com/portrait/charcoal-1.jpg');
    background-size: auto 100%;
    background-repeat: no-repeat;
    background-position: left top;
}

UIAlertView first deprecated IOS 9

 
-(void)showAlert{

    UIAlertController* alert = [UIAlertController alertControllerWithTitle:@"Title"
                                                                   message:"Message"
                                                            preferredStyle:UIAlertControllerStyleAlert];

    UIAlertAction* defaultAction = [UIAlertAction actionWithTitle:@"OK" style:UIAlertActionStyleDefault
                                                          handler:^(UIAlertAction * action) {}];

    [alert addAction:defaultAction];
    [self presentViewController:alert animated:YES completion:nil];
}

[self showAlert]; // calling Method

PHP function use variable from outside

Just put in the function using GLOBAL keyword:

 global $site_url;

Replace a string in shell script using a variable

 
echo $LINE | sed -e 's/12345678/'$replace'/g'

you can still use single quotes, but you have to "open" them when you want the variable expanded at the right place. otherwise the string is taken "literally" (as @paxdiablo correctly stated, his answer is correct as well)

Git merge is not possible because I have unmerged files

I ran into the same issue and couldn't decide between laughing or smashing my head on the table when I read this error...

What git really tries to tell you: "You are already in a merge state and need to resolve the conflicts there first!"

You tried a merge and a conflict occured. Then, git stays in the merge state and if you want to resolve the merge with other commands git thinks you want to execute a new merge and so it tells you you can't do this because of your current unmerged files...

You can leave this state with git merge --abort and now try to execute other commands.

In my case I tried a pull and wanted to resolve the conflicts by hand when the error occured...

How to source virtualenv activate in a Bash script

You should use multiple commands in one line. for example:

os.system(". Projects/virenv/bin/activate && python Projects/virenv/django-project/manage.py runserver")

when you activate your virtual environment in one line, I think it forgets for other command lines and you can prevent this by using multiple commands in one line. It worked for me :)

How to pass multiple arguments in processStartInfo?

It is purely a string:

startInfo.Arguments = "-sk server -sky exchange -pe -n CN=localhost -ir LocalMachine -is Root -ic MyCA.cer -sr LocalMachine -ss My MyAdHocTestCert.cer"

Of course, when arguments contain whitespaces you'll have to escape them using \" \", like:

"... -ss \"My MyAdHocTestCert.cer\""

See MSDN for this.

PHP CURL Enable Linux

If it's php 7 on ubuntu, try this

apt-get install php7.0-curl
/etc/init.d/apache2 restart

C# - What does the Assert() method do? Is it still useful?

You should use it for times when you don't want to have to breakpoint every little line of code to check variables, but you do want to get some sort of feedback if certain situations are present, for example:

Debug.Assert(someObject != null, "someObject is null! this could totally be a bug!");

How to set HTTP headers (for cache-control)?

To use cache-control in HTML, you use the meta tag, e.g.

<meta http-equiv="Cache-control" content="public">

The value in the content field is defined as one of the four values below.

Some information on the Cache-Control header is as follows

HTTP 1.1. Allowed values = PUBLIC | PRIVATE | NO-CACHE | NO-STORE.

Public - may be cached in public shared caches.
Private - may only be cached in private cache.
No-Cache - may not be cached.
No-Store - may be cached but not archived.

The directive CACHE-CONTROL:NO-CACHE indicates cached information should not be used and instead requests should be forwarded to the origin server. This directive has the same semantics as the PRAGMA:NO-CACHE.

Clients SHOULD include both PRAGMA: NO-CACHE and CACHE-CONTROL: NO-CACHE when a no-cache request is sent to a server not known to be HTTP/1.1 compliant. Also see EXPIRES.

Note: It may be better to specify cache commands in HTTP than in META statements, where they can influence more than the browser, but proxies and other intermediaries that may cache information.

How to export the Html Tables data into PDF using Jspdf

There is a tablePlugin for jspdf it expects array of objects and displays that data as a table. You can style the text and headers with little changes in the code. It is open source and also has examples for you to get started with.

Find and replace words/lines in a file

Any decent text editor has a search&replace facility that supports regular expressions.

If however, you have reason to reinvent the wheel in Java, you can do:

Path path = Paths.get("test.txt");
Charset charset = StandardCharsets.UTF_8;

String content = new String(Files.readAllBytes(path), charset);
content = content.replaceAll("foo", "bar");
Files.write(path, content.getBytes(charset));

This only works for Java 7 or newer. If you are stuck on an older Java, you can do:

String content = IOUtils.toString(new FileInputStream(myfile), myencoding);
content = content.replaceAll(myPattern, myReplacement);
IOUtils.write(content, new FileOutputStream(myfile), myencoding);

In this case, you'll need to add error handling and close the streams after you are done with them.

IOUtils is documented at http://commons.apache.org/proper/commons-io/javadocs/api-release/org/apache/commons/io/IOUtils.html

PersistenceContext EntityManager injection NullPointerException

An entity manager can only be injected in classes running inside a transaction. In other words, it can only be injected in a EJB. Other classe must use an EntityManagerFactory to create and destroy an EntityManager.

Since your TestService is not an EJB, the annotation @PersistenceContext is simply ignored. Not only that, in JavaEE 5, it's not possible to inject an EntityManager nor an EntityManagerFactory in a JAX-RS Service. You have to go with a JavaEE 6 server (JBoss 6, Glassfish 3, etc).

Here's an example of injecting an EntityManagerFactory:

package com.test.service;

import java.util.*;
import javax.persistence.*;
import javax.ws.rs.*;

@Path("/service")
public class TestService {

    @PersistenceUnit(unitName = "test")
    private EntityManagerFactory entityManagerFactory;

    @GET
    @Path("/get")
    @Produces("application/json")
    public List get() {
        EntityManager entityManager = entityManagerFactory.createEntityManager();
        try {
            return entityManager.createQuery("from TestEntity").getResultList();
        } finally {
            entityManager.close();
        }
    }
}

The easiest way to go here is to declare your service as a EJB 3.1, assuming you're using a JavaEE 6 server.

Related question: Inject an EJB into JAX-RS (RESTful service)

Difference between Encapsulation and Abstraction

Let me explain it in with the same example discussed above. Kindly consider the same TV.

Encapsulation: The adjustments we can make with the remote is a good example - Volume UP/DOWN, Color & Contrast - All we can do is adjust it to the min and max value provided and cannot do anything beyond what is provided in the remote - Imagine the getter and setter here(The setter function will check whether the value provided is valid if Yes, it process the operation if not won't allow us to make changes - like we cannot decrease the volume beyond zero even we press the volume down button a hundred times).

Abstraction: We can take the same example here but with a higher Degree/Context. The volume down button will decrease the volume - and this is the info we provide to the user and the user is not aware of neither the infrared transmitter inside the remote nor the receiver in the TV and the subsequent process of parsing the signal and the microprocessor architecture inside the TV. Simply put it is not needed in the context - Just provide what is necessary. One can easily relate the Text book definition here ie., Hiding the inner implementation and only providing what it will do rather than how it do that!

Hope it clarifies a bit!

How is Pythons glob.glob ordered?

Please try this code:

sorted(glob.glob( os.path.join(path, '*.png') ),key=lambda x:float(re.findall("([0-9]+?)\.png",x)[0]))

Get only records created today in laravel

No need to use Carbon::today because laravel uses function now() instead as a helper function

So to get any records that have been created today you can use the below code:

Model::whereDay('created_at', now()->day)->get();

You need to use whereDate so created_at will be converted to date.

Convert a string into an int

You can also use like :

NSInteger getVal = [self.string integerValue];

How can I detect whether an iframe is loaded?

You can try onload event as well;

var createIframe = function (src) {
        var self = this;
        $('<iframe>', {
            src: src,
            id: 'iframeId',
            frameborder: 1,
            scrolling: 'no',
            onload: function () {
                self.isIframeLoaded = true;
                console.log('loaded!');
            }
        }).appendTo('#iframeContainer');

    };

How to abort makefile if variable not set?

You can use an IF to test:

check:
        @[ "${var}" ] || ( echo ">> var is not set"; exit 1 )

Result:

$ make check
>> var is not set
Makefile:2: recipe for target 'check' failed
make: *** [check] Error 1

How do I activate a specific workbook and a specific sheet?

 
Dim Wb As Excel.Workbook
Set Wb = Workbooks.Open(file_path)
Wb.Sheets("Sheet1").Cells(2,24).Value = 24
Wb.Close

To know the sheets name to refer in Wb.Sheets("sheetname") you can use the following :

Dim sht as Worksheet    
For Each sht In tempWB.Sheets
    Debug.Print sht.Name
Next sht

Updating Python on Mac

I personally wouldn't mess around with OSX's python like they said. My personally preference for stuff like this is just using MacPorts and installing the versions I want via command line. MacPorts puts everything into a separate direction (under /opt I believe), so it doesn't override or directly interfere with the regular system. It has all the usually features of any package management utilities if you are familiar with Linux distros.

I would also suggest installing python_select via MacPorts and using that to select which python you want "active" (it will change the symlinks to point to the version you want). So at any time you can switch back to the Apple maintained version of python that came with OSX or you can switch to any of the ones installed via MacPorts.

Android Debug Bridge (adb) device - no permissions

I had the same situation where three devices connected to one same host but only one had 'no permissions' others were online.

Adding SUID or SGID on adb was another issue for me. Devices seen offline every time adb restarts - until you acknowledge on the devices every time.

I solved this 'no permissions' issue by adding 'o+w' permission for a device file.

chmod o+w /dev/bus/usb/00n/xxx

Image steganography that could survive jpeg compression

Quite a few applications seem to implement Steganography on JPEG, so it's feasible:

http://www.jjtc.com/Steganography/toolmatrix.htm

Here's an article regarding a relevant algorithm (PM1) to get you started:

http://link.springer.com/article/10.1007%2Fs00500-008-0327-7#page-1

What's is the difference between include and extend in use case diagram?

This is great resource with great explanation: What is include at use case? What is Extend at use case?

Extending use case typically defines optional behavior. It is independent of the extending use case

Include used to extract common parts of the behaviors of two or more use cases

Using ALTER to drop a column if it exists in MySQL

For MySQL, there is none: MySQL Feature Request.

Allowing this is arguably a really bad idea, anyway: IF EXISTS indicates that you're running destructive operations on a database with (to you) unknown structure. There may be situations where this is acceptable for quick-and-dirty local work, but if you're tempted to run such a statement against production data (in a migration etc.), you're playing with fire.

But if you insist, it's not difficult to simply check for existence first in the client, or to catch the error.

MariaDB also supports the following starting with 10.0.2:

DROP [COLUMN] [IF EXISTS] col_name

i. e.

ALTER TABLE my_table DROP IF EXISTS my_column;

But it's arguably a bad idea to rely on a non-standard feature supported by only one of several forks of MySQL.

Can two Java methods have same name with different return types?

The java documentation states:

The compiler does not consider return type when differentiating methods, so you cannot declare two methods with the same signature even if they have a different return type.

See: http://docs.oracle.com/javase/tutorial/java/javaOO/methods.html

Parse JSON from HttpURLConnection object

You can get raw data using below method. BTW, this pattern is for Java 6. If you are using Java 7 or newer, please consider try-with-resources pattern.

public String getJSON(String url, int timeout) {
    HttpURLConnection c = null;
    try {
        URL u = new URL(url);
        c = (HttpURLConnection) u.openConnection();
        c.setRequestMethod("GET");
        c.setRequestProperty("Content-length", "0");
        c.setUseCaches(false);
        c.setAllowUserInteraction(false);
        c.setConnectTimeout(timeout);
        c.setReadTimeout(timeout);
        c.connect();
        int status = c.getResponseCode();

        switch (status) {
            case 200:
            case 201:
                BufferedReader br = new BufferedReader(new InputStreamReader(c.getInputStream()));
                StringBuilder sb = new StringBuilder();
                String line;
                while ((line = br.readLine()) != null) {
                    sb.append(line+"\n");
                }
                br.close();
                return sb.toString();
        }

    } catch (MalformedURLException ex) {
        Logger.getLogger(getClass().getName()).log(Level.SEVERE, null, ex);
    } catch (IOException ex) {
        Logger.getLogger(getClass().getName()).log(Level.SEVERE, null, ex);
    } finally {
       if (c != null) {
          try {
              c.disconnect();
          } catch (Exception ex) {
             Logger.getLogger(getClass().getName()).log(Level.SEVERE, null, ex);
          }
       }
    }
    return null;
}

And then you can use returned string with Google Gson to map JSON to object of specified class, like this:

String data = getJSON("http://localhost/authmanager.php");
AuthMsg msg = new Gson().fromJson(data, AuthMsg.class);
System.out.println(msg);

There is a sample of AuthMsg class:

public class AuthMsg {
    private int code;
    private String message;

    public int getCode() {
        return code;
    }
    public void setCode(int code) {
        this.code = code;
    }

    public String getMessage() {
        return message;
    }
    public void setMessage(String message) {
        this.message = message;
    }
}

JSON returned by http://localhost/authmanager.php must look like this:

{"code":1,"message":"Logged in"}

Regards

Validation failed for one or more entities. See 'EntityValidationErrors' property for more details

In debug, you can enter this in your QuickWatch expression evaluator entry field:

context.GetValidationErrors()

What is the purpose of mvnw and mvnw.cmd files?

These files are from Maven wrapper. It works similarly to the Gradle wrapper.

This allows you to run the Maven project without having Maven installed and present on the path. It downloads the correct Maven version if it's not found (as far as I know by default in your user home directory).

The mvnw file is for Linux (bash) and the mvnw.cmd is for the Windows environment.

To create or update all necessary Maven Wrapper files execute the following command:

mvn -N io.takari:maven:wrapper

To use a different version of maven you can specify the version as follows:

mvn -N io.takari:maven:wrapper -Dmaven=3.3.3

Both commands require maven on PATH (add the path to maven bin to Path on System Variables) if you already have mvnw in your project you can use ./mvnw instead of mvn in the commands.

Load dimension value from res/values/dimension.xml from source code

You can use getDimensionPixelOffset() instead of getDimension, so you didn't have to cast to int.

int valueInPixels = getResources().getDimensionPixelOffset(R.dimen.test)

string.Replace in AngularJs

In Javascript method names are camel case, so it's replace, not Replace:

$scope.newString = oldString.replace("stackover","NO");

Note that contrary to how the .NET Replace method works, the Javascript replace method replaces only the first occurrence if you are using a string as first parameter. If you want to replace all occurrences you need to use a regular expression so that you can specify the global (g) flag:

$scope.newString = oldString.replace(/stackover/g,"NO");

See this example.

Default keystore file does not exist?

In macOS, open the Terminal and type below command

~/.android

It will navigate to the folder that containing Keystore file (You can confirm it with 'ls' command)

In my case, there is a file named 'debug.keystore'. Then type below command in the terminal from the ~/.android directory.

keytool -list -v -keystore debug.keystore

You will get the expected output.

What is the difference between jQuery: text() and html() ?

The text() method entity-escapes any HTML that is passed into it. Use text() when you want to insert HTML code that will be visible to people who view the page.

Technically, your second example produces:

&lt;a href="example.html"&gt;Link&lt;/a&gt;&lt;b&gt;hello&lt;/b&gt;

which would be rendered in the browser as:

<a href="example.html">Link</a><b>hello</b>

Your first example will be rendered as an actual link and some bold text.

How to upgrade R in ubuntu?

Since R is already installed, you should be able to upgrade it with this method. First of all, you may want to have the packages you installed in the previous version in the new one,so it is convenient to check this post. Then, follow the instructions from here

  1. Open the sources.list file:

     sudo nano /etc/apt/sources.list

  2. Add a line with the source from where the packages will be retrieved. For example:

     deb https://cloud.r-project.org/bin/linux/ubuntu/ version/

    Replace https://cloud.r-project.org with whatever mirror you would like to use, and replace version/ with whatever version of Ubuntu you are using (eg, trusty/, xenial/, and so on). If you're getting a "Malformed line error", check to see if you have a space between /ubuntu/ and version/.

  3. Fetch the secure APT key:

     gpg --keyserver keyserver.ubuntu.com --recv-key E298A3A825C0D65DFD57CBB651716619E084DAB9

or

    gpg --hkp://keyserver keyserver.ubuntu.com:80 --recv-key E298A3A825C0D65DFD57CBB651716619E084DAB9

  1. Add it to keyring:

     gpg -a --export E084DAB9 | sudo apt-key add -

  2. Update your sources and upgrade your installation:

     sudo apt-get update && sudo apt-get upgrade

  3. Install the new version

     sudo apt-get install r-base-dev

  4. Recover your old packages following the solution that best suits to you (see this). For instance, to recover all the packages (not only those from CRAN) the idea is:

-- copy the packages from R-oldversion/library to R-newversion/library, (do not overwrite a package if it already exists in the new version!).

-- Run the R command update.packages(checkBuilt=TRUE, ask=FALSE).

How to recursively find and list the latest modified files in a directory with subdirectories and times

GNU find (see man find) has a -printf parameter for displaying the files in Epoch mtime and relative path name.

redhat> find . -type f -printf '%T@ %P\n' | sort -n | awk '{print $2}'

`export const` vs. `export default` in ES6

When you put default, its called default export. You can only have one default export per file and you can import it in another file with any name you want. When you don't put default, its called named export, you have to import it in another file using the same name with curly braces inside it.

How to convert int to float in C?

I routinely multiply by 1.0 if I want floating point, it's easier than remembering the rules.

How to find where javaw.exe is installed?

Try this

for %i in (javaw.exe) do @echo. %~$PATH:i

VBA procedure to import csv file into access

Your file seems quite small (297 lines) so you can read and write them quite quickly. You refer to Excel CSV, which does not exists, and you show space delimited data in your example. Furthermore, Access is limited to 255 columns, and a CSV is not, so there is no guarantee this will work

Sub StripHeaderAndFooter()
Dim fs As Object ''FileSystemObject
Dim tsIn As Object, tsOut As Object ''TextStream
Dim sFileIn As String, sFileOut As String
Dim aryFile As Variant

    sFileIn = "z:\docs\FileName.csv"
    sFileOut = "z:\docs\FileOut.csv"

    Set fs = CreateObject("Scripting.FileSystemObject")
    Set tsIn = fs.OpenTextFile(sFileIn, 1) ''ForReading

    sTmp = tsIn.ReadAll

    Set tsOut = fs.CreateTextFile(sFileOut, True) ''Overwrite
    aryFile = Split(sTmp, vbCrLf)

    ''Start at line 3 and end at last line -1
    For i = 3 To UBound(aryFile) - 1
        tsOut.WriteLine aryFile(i)
    Next

    tsOut.Close

    DoCmd.TransferText acImportDelim, , "NewCSV", sFileOut, False
End Sub

Edit re various comments

It is possible to import a text file manually into MS Access and this will allow you to choose you own cell delimiters and text delimiters. You need to choose External data from the menu, select your file and step through the wizard.

About importing and linking data and database objects -- Applies to: Microsoft Office Access 2003

Introduction to importing and exporting data -- Applies to: Microsoft Access 2010

Once you get the import working using the wizards, you can save an import specification and use it for you next DoCmd.TransferText as outlined by @Olivier Jacot-Descombes. This will allow you to have non-standard delimiters such as semi colon and single-quoted text.

What does the 'b' character do in front of a string literal?

The answer to the question is that, it does:

data.encode()

and in order to decode it(remove the b, because sometimes you don't need it)

use:

data.decode()

How to run multiple Python versions on Windows

As per @alexander you can make a set of symbolic links like below. Put them somewhere which is included in your path so they can be easily invoked

> cd c:\bin
> mklink python25.exe c:\python25\python.exe
> mklink python26.exe c:\python26\python.exe

As long as c:\bin or where ever you placed them in is in your path you can now go

> python25

How to select specified node within Xpath node sets by index with Selenium?

 
//img[@title='Modify'][i]

is short for

/descendant-or-self::node()/img[@title='Modify'][i]

hence is returning the i'th node under the same parent node.

You want

/descendant-or-self::img[@title='Modify'][i]

How to filter keys of an object with lodash?

Lodash has a _.pickBy function which does exactly what you're looking for.

_x000D_
_x000D_ 
var thing = {_x000D_
  "a": 123,_x000D_
  "b": 456,_x000D_
  "abc": 6789_x000D_
};_x000D_
_x000D_
var result = _.pickBy(thing, function(value, key) {_x000D_
  return _.startsWith(key, "a");_x000D_
});_x000D_
_x000D_
console.log(result.abc) // 6789_x000D_
console.log(result.b)   // undefined
_x000D_ 
<script src="https://cdn.jsdelivr.net/lodash/4.16.4/lodash.min.js"></script>
_x000D_
_x000D_
_x000D_

Flutter : Vertically center column

Try this one. It centers vertically and horizontally.

Center(
  child: Column(
    mainAxisAlignment: MainAxisAlignment.center,
    children: children,
  ),
)

Using PHP Replace SPACES in URLS with %20

Use urlencode() rather than trying to implement your own. Be lazy.

JQuery Ajax Post results in 500 Internal Server Error

In my case it was simple issue, but hard to find. Page directive had wrong Inherits attributes. It just need to include the top level and it worked.

Wrong code

<%@ Page Language="C#" CodeBehind="BusLogic.aspx.cs" Inherits="BusLogic"%>

Correct code

<%@ Page Language="C#" CodeBehind="BusLogic.aspx.cs" Inherits="Web.BusLogic" %>

pandas how to check dtype for all columns in a dataframe?

Suppose df is a pandas DataFrame then to get number of non-null values and data types of all column at once use:

df.info()

Select rows of a matrix that meet a condition

I will choose a simple approach using the dplyr package.

If the dataframe is data.

library(dplyr)
result <- filter(data, three == 11)

SQL Server : How to test if a string has only digit characters

I was attempting to find strings with numbers ONLY, no punctuation or anything else. I finally found an answer that would work here.

Using PATINDEX('%[^0-9]%', some_column) = 0 allowed me to filter out everything but actual number strings.

What is a "thread" (really)?

Let me explain the difference between process and threads first.

A process can have {1..N} number of threads. A small explanation on virtual memory and virtual processor.

Virtual memory

Used as a swap space so that a process thinks that it is sitting on the primary memory for execution.

Virtual processor

The same concept as virtual memory except this is for processor. To a process, it will look it's the only thing that is using the processor.

OS will take care of allocating the virtual memory and virtual processor to a process and performing the swap between processes and doing execution.

All the threads within a process will share the same virtual memory. But, each thread will have their individual virtual processor assigned to them so that they can be executed individually.

Thus saving the memory as well as utilizing the CPU to its potential.

Mocking python function based on input arguments

Just to show another way of doing it:

def mock_isdir(path):
    return path in ['/var/log', '/var/log/apache2', '/var/log/tomcat']

with mock.patch('os.path.isdir') as os_path_isdir:
    os_path_isdir.side_effect = mock_isdir

file_get_contents() Breaks Up UTF-8 Characters

Try this function

function mb_html_entity_decode($string) {
if (extension_loaded('mbstring') === true)
{
    mb_language('Neutral');
    mb_internal_encoding('UTF-8');
    mb_detect_order(array('UTF-8', 'ISO-8859-15', 'ISO-8859-1', 'ASCII'));

    return mb_convert_encoding($string, 'UTF-8', 'HTML-ENTITIES');
}

return html_entity_decode($string, ENT_COMPAT, 'UTF-8');

}

Why is conversion from string constant to 'char*' valid in C but invalid in C++

You can declare like one of the below options:

char data[] = "Testing String";

or

const char* data = "Testing String";

or

char* data = (char*) "Testing String";

How to query DATETIME field using only date in Microsoft SQL Server?

 
select *
  from invoice
 where TRUNC(created_date) <=TRUNC(to_date('04-MAR-18 15:00:00','dd-mon-yy hh24:mi:ss'));

How to get a web page's source code from Java

Try the following code with an added request property:

import java.io.BufferedReader;
import java.io.IOException;
import java.io.InputStream;
import java.io.InputStreamReader;
import java.net.URL;
import java.net.URLConnection;

public class SocketConnection
{
    public static String getURLSource(String url) throws IOException
    {
        URL urlObject = new URL(url);
        URLConnection urlConnection = urlObject.openConnection();
        urlConnection.setRequestProperty("User-Agent", "Mozilla/5.0 (Windows NT 6.1; WOW64) AppleWebKit/537.11 (KHTML, like Gecko) Chrome/23.0.1271.95 Safari/537.11");

        return toString(urlConnection.getInputStream());
    }

    private static String toString(InputStream inputStream) throws IOException
    {
        try (BufferedReader bufferedReader = new BufferedReader(new InputStreamReader(inputStream, "UTF-8")))
        {
            String inputLine;
            StringBuilder stringBuilder = new StringBuilder();
            while ((inputLine = bufferedReader.readLine()) != null)
            {
                stringBuilder.append(inputLine);
            }

            return stringBuilder.toString();
        }
    }
}

Bootstrap modal z-index

The modal dialog can be positioned on top by overriding its z-index property:

.modal.fade {
  z-index: 10000000 !important;
}

Convert String to Double - VB

 
Dim text As String = "123.45"
Dim value As Double
If Double.TryParse(text, value) Then
    ' text is convertible to Double, and value contains the Double value now
Else
    ' Cannot convert text to Double
End If

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

Swift 3.0 Version of Jake's Answer

// Create the alert controller

let alertController = UIAlertController(title: "Alert!", message: "There is no items for the current user", preferredStyle: .alert)

            // Create the actions
            let okAction = UIAlertAction(title: "OK", style: UIAlertActionStyle.default) {
                UIAlertAction in
                NSLog("OK Pressed")
            }
            let cancelAction = UIAlertAction(title: "Cancel", style: UIAlertActionStyle.cancel) {
                UIAlertAction in
                NSLog("Cancel Pressed")
            }

            // Add the actions
            alertController.addAction(okAction)
            alertController.addAction(cancelAction)

            // Present the controller
            self.present(alertController, animated: true, completion: nil)

Understanding Popen.communicate

Your second bit of code starts the first bit of code as a subprocess with piped input and output. It then closes its input and tries to read its output.

The first bit of code tries to read from standard input, but the process that started it closed its standard input, so it immediately reaches an end-of-file, which Python turns into an exception.

stop service in android

 
onDestroyed()

is wrong name for 

onDestroy()

Did you make a mistake only in this question or in your code too?

Select all where [first letter starts with B]

 
SELECT author FROM lyrics WHERE author LIKE 'B%';

Make sure you have an index on author, though!

Limit the size of a file upload (html input element)

This is completely possible. Use Javascript.

I use jQuery to select the input element. I have it set up with an on change event.

$("#aFile_upload").on("change", function (e) {

    var count=1;
    var files = e.currentTarget.files; // puts all files into an array

    // call them as such; files[0].size will get you the file size of the 0th file
    for (var x in files) {

        var filesize = ((files[x].size/1024)/1024).toFixed(4); // MB

        if (files[x].name != "item" && typeof files[x].name != "undefined" && filesize <= 10) { 

            if (count > 1) {

                approvedHTML += ", "+files[x].name;
            }
            else {

                approvedHTML += files[x].name;
            }

            count++;
        }
    }
    $("#approvedFiles").val(approvedHTML);

});

The code above saves all the file names that I deem worthy of persisting to the submission page, before the submit actually happens. I add the "approved" files to an input element's val using jQuery so a form submit will send the names of the files I want to save. All the files will be submitted, however, now on the server side we do have to filter these out. I haven't written any code for that yet, but use your imagination. I assume one can accomplish this by a for loop and matching the names sent over from the input field and match them to the $_FILES(PHP Superglobal, sorry I dont know ruby file variable) variable.

My point is you can do checks for files before submission. I do this and then output it to the user before he/she submits the form, to let them know what they are uploading to my site. Anything that doesn't meet the criteria does not get displayed back to the user and therefore they should know, that the files that are too large wont be saved. This should work on all browsers because I'm not using FormData object.

One-line list comprehension: if-else variants

x if y else z is the syntax for the expression you're returning for each element. Thus you need:

[ x if x%2 else x*100 for x in range(1, 10) ]

The confusion arises from the fact you're using a filter in the first example, but not in the second. In the second example you're only mapping each value to another, using a ternary-operator expression.

With a filter, you need:

[ EXP for x in seq if COND ]

Without a filter you need:

[ EXP for x in seq ]

and in your second example, the expression is a "complex" one, which happens to involve an if-else.

Python: How to check if keys exists and retrieve value from Dictionary in descending priority

One option if the number of keys is small is to use chained gets:

value = myDict.get('lastName', myDict.get('firstName', myDict.get('userName')))

But if you have keySet defined, this might be clearer:

value = None
for key in keySet:
    if key in myDict:
        value = myDict[key]
        break

The chained gets do not short-circuit, so all keys will be checked but only one used. If you have enough possible keys that that matters, use the for loop.

C compiler for Windows?

MinGW would be a direct translation off gcc for windows, or you might want to check out LCC, vanilla c (more or less) with an IDE. Pelles C seems to be based off lcc and has a somewhat nicer IDE, though I haven't used it personally. Of course there is always the Express Edition of MSVC which is free, but that's your call.

omp parallel vs. omp parallel for

I don't think there is any difference, one is a shortcut for the other. Although your exact implementation might deal with them differently.

The combined parallel worksharing constructs are a shortcut for specifying a parallel construct containing one worksharing construct and no other statements. Permitted clauses are the union of the clauses allowed for the parallel and worksharing contructs.

Taken from http://www.openmp.org/mp-documents/OpenMP3.0-SummarySpec.pdf

The specs for OpenMP are here:

https://openmp.org/specifications/

Get selected value/text from Select on change

Use 

document.getElementById("select_id").selectedIndex

Or to get the value:

document.getElementById("select_id").value

Is there a difference between using a dict literal and a dict constructor?

Literal is much faster, since it uses optimized BUILD_MAP and STORE_MAP opcodes rather than generic CALL_FUNCTION:

> python2.7 -m timeit "d = dict(a=1, b=2, c=3, d=4, e=5)"
1000000 loops, best of 3: 0.958 usec per loop

> python2.7 -m timeit "d = {'a':1, 'b':2, 'c':3, 'd':4, 'e':5}"
1000000 loops, best of 3: 0.479 usec per loop

> python3.2 -m timeit "d = dict(a=1, b=2, c=3, d=4, e=5)"
1000000 loops, best of 3: 0.975 usec per loop

> python3.2 -m timeit "d = {'a':1, 'b':2, 'c':3, 'd':4, 'e':5}"
1000000 loops, best of 3: 0.409 usec per loop

How to import a Python class that is in a directory above?

@gimel's answer is correct if you can guarantee the package hierarchy he mentions. If you can't -- if your real need is as you expressed it, exclusively tied to directories and without any necessary relationship to packaging -- then you need to work on __file__ to find out the parent directory (a couple of os.path.dirname calls will do;-), then (if that directory is not already on sys.path) prepend temporarily insert said dir at the very start of sys.path, __import__, remove said dir again -- messy work indeed, but, "when you must, you must" (and Pyhon strives to never stop the programmer from doing what must be done -- just like the ISO C standard says in the "Spirit of C" section in its preface!-).

Here is an example that may work for you:

import sys
import os.path
sys.path.append(
    os.path.abspath(os.path.join(os.path.dirname(__file__), os.path.pardir)))

import module_in_parent_dir

How to check for file existence

Check out Pathname and in particular Pathname#exist?.

File and its FileTest module are perhaps simpler/more direct, but I find Pathname a nicer interface in general.

Can I create a One-Time-Use Function in a Script or Stored Procedure?

Common Table Expressions let you define what are essentially views that last only within the scope of your select, insert, update and delete statements. Depending on what you need to do they can be terribly useful.

Html5 Full screen video

No, there is no way to do this yet. I wish they add a future like this in browsers.

EDIT:

Now there is a Full Screen API for the web You can requestFullscreen on an Video or Canvas element to ask user to give you permisions and make it full screen.

Let's consider this element:

<video controls id="myvideo">
  <source src="somevideo.webm"></source>
  <source src="somevideo.mp4"></source>
</video>

We can put that video into fullscreen mode with script like this:

var elem = document.getElementById("myvideo");
if (elem.requestFullscreen) {
  elem.requestFullscreen();
} else if (elem.mozRequestFullScreen) {
  elem.mozRequestFullScreen();
} else if (elem.webkitRequestFullscreen) {
  elem.webkitRequestFullscreen();
} else if (elem.msRequestFullscreen) { 
  elem.msRequestFullscreen();
}

Full documentation

Should I use alias or alias_method?

I think there is an unwritten rule (something like a convention) that says to use 'alias' just for registering a method-name alias, means if you like to give the user of your code one method with more than one name:

class Engine
  def start
    #code goes here
  end
  alias run start
end

If you need to extend your code, use the ruby meta alternative.

class Engine
  def start
    puts "start me"
  end
end

Engine.new.start() # => start me

Engine.class_eval do
  unless method_defined?(:run)
    alias_method :run, :start
    define_method(:start) do
      puts "'before' extension"
      run()
      puts "'after' extension"
    end
  end
end

Engine.new.start
# => 'before' extension
# => start me
# => 'after' extension

Engine.new.run # => start me

How to remove underline from a name on hover

To keep the color and prevent an underline on the link:

legend.green-color a{
    color:green;
    text-decoration: none;
}

How do I add space between two variables after a print in Python

A quick warning, this a pretty wordy answer.

print is tricky sometimes, I had some problems with it when I first started. What you want is a few spaces in between two variables after you print them right? There's many ways to do this, as shown in the above answers.

This is your code:

count = 1
conv = count * 2.54
print count, conv

It's output is this:

1 2.54

If you want spaces in between, you can do it the naive way by sticking a string of spaces in between them. The variables count and conv need to be converted to string types to concatenate(join) them together. This is done with str().

print (str(count) + "           " + str(conv))
### Provides an output of:
1           2.54

To do this is the newer, more pythonic way, we use the % sign in conjunction with a letter to denote the kind of value we're using. Here I use underscores instead of spaces to show how many there are. The modulo before the last values just tells python to insert the following values in, in the order we provided.

print ('%i____%s' % (count, conv))
### provides an output of:
1____2.54

I used %i for count because it is a whole number, and %s for conv, because using %i in that instance would provide us with "2" instead of "2.54" Technically, I could've used both %s, but it's all good.

I hope this helps!

-Joseph

P.S. if you want to get complicated with your formatting, you should look at prettyprint for large amounts of text such as dictionaries and tuple lists(imported as pprint) as well as which does automatic tabs, spacing and other cool junk.

Here's some more information about strings in the python docs. http://docs.python.org/library/string.html#module-string

Convert month int to month name

You can do something like this instead.

return new DateTime(2010, Month, 1).ToString("MMM");

Specify sudo password for Ansible

This worked for me... Created file /etc/sudoers.d/90-init-users file with NOPASSWD

echo "user ALL=(ALL)       NOPASSWD:ALL" > 90-init-users

where "user" is your userid.

how to remove empty strings from list, then remove duplicate values from a list

 
dtList  = dtList.Where(s => !string.IsNullOrWhiteSpace(s)).Distinct().ToList()

I assumed empty string and whitespace are like null. If not you can use IsNullOrEmpty (allow whitespace), or s != null

Formatting struct timespec

You can pass the tv_sec parameter to some of the formatting function. Have a look at gmtime, localtime(). Then look at snprintf.

Show whitespace characters in Visual Studio Code

VS Code 1.6.0 and Greater

As mentioned by aloisdg below, editor.renderWhitespace is now an enum taking either none, boundary or all. To view all whitespaces:

"editor.renderWhitespace": "all",

Before VS Code 1.6.0

Before 1.6.0, you had to set editor.renderWhitespace to true:

"editor.renderWhitespace": true

New xampp security concept: Access Forbidden Error 403 - Windows 7 - phpMyAdmin

You will have to edit 2 files - 1. httpd-vhosts.conf & 2. httpd-xampp.conf

NOTE : Make sure u backup files ( httpd-xampp.conf ) and ( httpd-vhosts.conf ) , Both Files are located in Drive:\xampp\apache\conf\extra

Open httpd-vhosts.conf file and in the bottom of the file change it

<VirtualHost *:80>
DocumentRoot “E:/xampp/htdocs/”
ServerName localhost
<Directory E:/xampp/htdocs/>.
Require all granted 
</Directory>
</VirtualHost>

Here E:/xampp is my project workspace, you can change it as per your settings

and Second Change is on httpd-xampp.conf file and in the bottom of the file change it

#
# New XAMPP security concept
#
<LocationMatch “^/(?i:(?:xampp|security|licenses|phpmyadmin|webalizer|server-status|server-info))”>
Order deny,allow
Allow from all
Allow from ::1 127.0.0.0/8
ErrorDocument 403 /error/XAMPP_FORBIDDEN.html.var
</LocationMatch>

java - iterating a linked list

Linked list is guaranteed to act in sequential order.

From the documentation

An ordered collection (also known as a sequence). The user of this interface has precise control over where in the list each element is inserted. The user can access elements by their integer index (position in the list), and search for elements in the list.

iterator() Returns an iterator over the elements in this list in proper sequence.

How do you handle a "cannot instantiate abstract class" error in C++?

An abstract class cannot be instantiated by definition. In order to use this class, you must create a concrete subclass which implements all virtual functions of the class. In this case, you most likely have not implemented all the virtual functions declared in Light. This means that AmbientOccluder defaults to an abstract class. For us to further help you, you should include the details of the Light class.

How many characters can you store with 1 byte?

1 byte may hold 1 character. For Example: Refer Ascii values for each character & convert into binary. This is how it works.

enter image description here value 255 is stored as (11111111) base 2. Visit this link for knowing more about binary conversion. http://acc6.its.brooklyn.cuny.edu/~gurwitz/core5/nav2tool.html

Size of Tiny Int = 1 Byte ( -128 to 127)

Int = 4 Bytes (-2147483648 to 2147483647)

Convert python long/int to fixed size byte array

Everyone has overcomplicated this answer:

some_int = <256 bit integer>
some_bytes = some_int.to_bytes(32, sys.byteorder)
my_bytearray = bytearray(some_bytes)

You just need to know the number of bytes that you are trying to convert. In my use cases, normally I only use this large of numbers for crypto, and at that point I have to worry about modulus and what-not, so I don't think this is a big problem to be required to know the max number of bytes to return.

Since you are doing it as 768-bit math, then instead of 32 as the argument it would be 96.

NVIDIA-SMI has failed because it couldn't communicate with the NVIDIA driver

My system version: ubuntu 20.04 LTS.

  • I solved this by generate a new MOK and enroll it into shim.

  • Without disable of Secure Boot, although it also really works for me.

  • Simply execute this command and follow what it suggests:

    sudo update-secureboot-policy --enroll-key

According to ubuntu's wiki: How can I do non-automated signing of drivers

How can I delete Docker's images?

The reason for the error is that even though the image did not have any tag, there still exists a container created on that image which might be in the exited state. So you need to ensure that you have stopped and deleted all containers created on those images. The following command helps you in removing all containers that are not running:

docker rm `docker ps -aq --no-trunc --filter "status=exited"`

Now this removes all the dangling non-intermediate <none> images:

docker rmi `docker images --filter 'dangling=true' -q --no-trunc`

Note: To stops all running containers:

docker stop `docker ps -q`

ERROR in ./node_modules/css-loader?

I tried both

npm rebuild node-sass

and

npm install --save node-sass

Later by seeing EACCESS, i checked the folder permission of /node_modules, which was not 777 permission

Then I gave

chmod -R 777 *

-R for recursively(setting the same permission not in the dir but also inside nested sub dir) * is for all files in current directory

What is file permission

To check for permission you can use

ls -l

If u don't know about it, first see here, then check the url

Every file and directory has permission of 'rwx'(read, write, execute). and if 'x' permission is not there, then you can not execture, if no 'w', you can not write into the file. if some thing is missiing it will show in place of r/w/x with '-'. So, if 'x' permission is not there, it will show like 'rw-'

And there will be 3 category of user Owner(who created the file/directory), Group(some people who shares same permission and user previlege), Others(general public)

So 1st letter is 'd'(if it is a directory) or '-'(if it is not a directory), followed by rwx for owner, followed by for group, followed by other

drwxrwxrwx

For example, for 'node_modules'directory I want to give permission to owner all permission and for rest only read, then it will be 

drwxr--r--

And about the number assume for 'r/w/x' it is 1 and for '-' it is 0, 777, first 7 is for owner, followed by group, followed by other

Let's assume the permission is rwxr-xrw-

Now 'rwx' is like '111' and it's equivalent decimal is 1*2^2+1*2^1+1*2^0=7

Now 'r-x' is like '101' and it's equivalent decimal is 1*2^2+0*2^1+1*2^0=5

Now 'rw-' is like '110' and it's equivalent decimal is 1*2^2+1*2^1+0*2^0=6

So, it will be 756

Why does printf not flush after the call unless a newline is in the format string?

There are generally 2 levels of buffering-

1. Kernel buffer Cache (makes read/write faster)

2. Buffering in I/O library (reduces no. of system calls)

Let's take example of fprintf and write().

When you call fprintf(), it doesn't wirte directly to the file. It first goes to stdio buffer in the program's memory. From there it is written to the kernel buffer cache by using write system call. So one way to skip I/O buffer is directly using write(). Other ways are by using setbuff(stream,NULL). This sets the buffering mode to no buffering and data is directly written to kernel buffer. To forcefully make the data to be shifted to kernel buffer, we can use "\n", which in case of default buffering mode of 'line buffering', will flush I/O buffer. Or we can use fflush(FILE *stream).

Now we are in kernel buffer. Kernel(/OS) wants to minimise disk access time and hence it reads/writes only blocks of disk. So when a read() is issued, which is a system call and can be invoked directly or through fscanf(), kernel reads the disk block from disk and stores it in a buffer. After that data is copied from here to user space.

Similarly that fprintf() data recieved from I/O buffer is written to the disk by the kernel. This makes read() write() faster.

Now to force the kernel to initiate a write(), after which data transfer is controlled by hardware controllers, there are also some ways. We can use O_SYNC or similar flags during write calls. Or we could use other functions like fsync(),fdatasync(),sync() to make the kernel initiate writes as soon as data is available in the kernel buffer.

Import-CSV and Foreach

Solution is to change Delimiter.

Content of the csv file -> Note .. Also space and , in value

Values are 6 Dutch word aap,noot,mies,Piet, Gijs, Jan

Col1;Col2;Col3

a,ap;noo,t;mi es

P,iet;G ,ijs;Ja ,n



$csv = Import-Csv C:\TejaCopy.csv -Delimiter ';'

Answer:

Write-Host $csv
@{Col1=a,ap; Col2=noo,t; Col3=mi es} @{Col1=P,iet; Col2=G ,ijs; Col3=Ja ,n}

It is possible to read a CSV file and use other Delimiter to separate each column.

It worked for my script :-)

Convert string to Time

This gives you the needed results:

string time = "16:23:01";
var result = Convert.ToDateTime(time);
string test = result.ToString("hh:mm:ss tt", CultureInfo.CurrentCulture);
//This gives you "04:23:01 PM"  string

You could also use CultureInfo.CreateSpecificCulture("en-US") as not all cultures will display AM/PM.

How can I display a tooltip on an HTML "option" tag?

I don't believe that you can achieve this functionality with standard <select> element.

What i would suggest is to use such way.

http://filamentgroup.com/lab/jquery_ipod_style_and_flyout_menus/

The basic version of it won't take too much space and you can easily bind mouseover events to sub items to show a nice tooltip.

Hope this helps, Sinan.

How do I run a Java program from the command line on Windows?

enter image description here STEP 1: FIRST OPEN THE COMMAND PROMPT WHERE YOUR FILE IS LOCATED. (right click while pressing shift)
STEP 2: THEN USE THE FOLLOWING COMMANDS TO EXECUTE. (lets say the file and class name to be executed is named as Student.java)The example program is in the picture background.

     javac Student.java
     java Student

enter image description here

Explicit vs implicit SQL joins

Personally I prefer the join syntax as its makes it clearer that the tables are joined and how they are joined. Try compare larger SQL queries where you selecting from 8 different tables and you have lots of filtering in the where. By using join syntax you separate out the parts where the tables are joined, to the part where you are filtering the rows.

How do you delete all text above a certain line

 
dgg

will delete everything from your current line to the top of the file.

d is the deletion command, and gg is a movement command that says go to the top of the file, so when used together, it means delete from my current position to the top of the file.

Also

dG

will delete all lines at or below the current one

JavaScript DOM: Find Element Index In Container

2017 update

The original answer below assumes that the OP wants to include non-empty text node and other node types as well as elements. It doesn't seem clear to me now from the question whether this is a valid assumption.

Assuming instead you just want the element index, previousElementSibling is now well-supported (which was not the case in 2012) and is the obvious choice now. The following (which is the same as some other answers here) will work in everything major except IE <= 8.

function getElementIndex(node) {
    var index = 0;
    while ( (node = node.previousElementSibling) ) {
        index++;
    }
    return index;
}

Original answer

Just use previousSibling until you hit null. I'm assuming you want to ignore white space-only text nodes; if you want to filter other nodes then adjust accordingly.

function getNodeIndex(node) {
    var index = 0;
    while ( (node = node.previousSibling) ) {
        if (node.nodeType != 3 || !/^\s*$/.test(node.data)) {
            index++;
        }
    }
    return index;
}

Find unique rows in numpy.array

Based on the answer in this page I have written a function that replicates the capability of MATLAB's unique(input,'rows') function, with the additional feature to accept tolerance for checking the uniqueness. It also returns the indices such that c = data[ia,:] and data = c[ic,:]. Please report if you see any discrepancies or errors.

def unique_rows(data, prec=5):
    import numpy as np
    d_r = np.fix(data * 10 ** prec) / 10 ** prec + 0.0
    b = np.ascontiguousarray(d_r).view(np.dtype((np.void, d_r.dtype.itemsize * d_r.shape[1])))
    _, ia = np.unique(b, return_index=True)
    _, ic = np.unique(b, return_inverse=True)
    return np.unique(b).view(d_r.dtype).reshape(-1, d_r.shape[1]), ia, ic

UICollectionView auto scroll to cell at IndexPath

You can use GCD to dispatch the scroll into the next iteration of main run loop in viewDidLoad to achieve this behavior. The scroll will be performed before the collection view is showed on screen, so there will be no flashing. 

- (void)viewDidLoad {
    dispatch_async (dispatch_get_main_queue (), ^{
        NSIndexPath *indexPath = YOUR_DESIRED_INDEXPATH;
        [self.collectionView scrollToItemAtIndexPath:indexPath atScrollPosition:UICollectionViewScrollPositionCenteredHorizontally animated:NO];
    });
}

How to select where ID in Array Rails ActiveRecord without exception

To avoid exceptions killing your app you should catch those exceptions and treat them the way you wish, defining the behavior for you app on those situations where the id is not found.

begin
  current_user.comments.find(ids)
rescue
  #do something in case of exception found
end

Here's more info on exceptions in ruby.

Log4net rolling daily filename with date in the file name

I ended up using (note the '.log' filename and the single quotes around 'myfilename_'):

  <rollingStyle value="Date" />
  <datePattern value="'myfilename_'yyyy-MM-dd"/>
  <preserveLogFileNameExtension value="true" />
  <staticLogFileName value="false" />
  <file type="log4net.Util.PatternString" value="c:\\Logs\\.log" />

This gives me:

myfilename_2015-09-22.log
myfilename_2015-09-23.log
.
.

How to create our own Listener interface in android?

In the year of 2018, there's no need for listeners interfaces. You've got Android LiveData to take care of passing the desired result back to the UI components.

If I'll take Rupesh's answer and adjust it to use LiveData, it will like so:

public class Event {

    public LiveData<EventResult> doEvent() {
         /*
          * code code code
          */

         // and in the end

         LiveData<EventResult> result = new MutableLiveData<>();
         result.setValue(eventResult);
         return result;
    }
}

and now in your driver class MyTestDriver:

public class MyTestDriver {
    public static void main(String[] args) {
        Event e = new Event();
        e.doEvent().observe(this, new  Observer<EventResult>() {
            @Override
            public void onChanged(final EventResult er) {
                // do your work.
            }
        });
    }
}

For more information along with code samples you can read my post about it, as well as the offical docs:

When and why to use LiveData

Official docs

How to check if $? is not equal to zero in unix shell scripting?

 
<run your last command on this line>
a=${?}
if [ ${a} -ne 0 ]; then echo "do something"; fi

use whatever command you want to use instead of the echo "do something" command

Reason for Column is invalid in the select list because it is not contained in either an aggregate function or the GROUP BY clause

Suppose I have the following table T:

a   b
--------
1   abc
1   def
1   ghi
2   jkl
2   mno
2   pqr

And I do the following query:

SELECT a, b
FROM T
GROUP BY a

The output should have two rows, one row where a=1 and a second row where a=2.

But what should the value of b show on each of these two rows? There are three possibilities in each case, and nothing in the query makes it clear which value to choose for b in each group. It's ambiguous.

This demonstrates the single-value rule, which prohibits the undefined results you get when you run a GROUP BY query, and you include any columns in the select-list that are neither part of the grouping criteria, nor appear in aggregate functions (SUM, MIN, MAX, etc.).

Fixing it might look like this:

SELECT a, MAX(b) AS x
FROM T
GROUP BY a

Now it's clear that you want the following result:

a   x
--------
1   ghi
2   pqr

Rails 3 execute custom sql query without a model

 
connection = ActiveRecord::Base.connection
connection.execute("SQL query")

Using If else in SQL Select statement

I Have a Query With This result : 

SELECT Top 3
 id,
 Paytype
 FROM dbo.OrderExpresses
 WHERE CreateDate > '2018-04-08'

The Result is : 

22082   1
22083   2
22084   1

I Want Change The Code To String In Query, So I Use This Code : 

SELECT TOP 3
 id,
 CASE WHEN Paytype = 1 THEN N'Credit' ELSE N'Cash' END AS PayTypeString
 FROM dbo.OrderExpresses
 WHERE CreateDate > '2018-04-08'

And Result Is :)

22082   Credit
22083   Cash
22084   Credit

How to use document.getElementByName and getElementByTag?

It's getElementsByName() and getElementsByTagName() - note the "s" in "Elements", indicating that both functions return a list of elements, i.e., a NodeList, which you will access like an array. Note that the second function ends with "TagName" not "Tag".

Even if the function only returns one element it will still be in a NodeList of length one. So:

var els = document.getElementsByName('frmMain');
// els.length will be the number of elements returned
// els[0] will be the first element returned
// els[1] the second, etc.

Assuming your form is the first (or only) form on the page you can do this:

document.getElementsByName('frmMain')[0].elements
document.getElementsByTagName('table')[0].elements

When to Redis? When to MongoDB?

And you should use neither if you have plenty of RAM. Redis and MongoDB come to the price of a general purpose tool. This introduce a lot of overhead.

There was the saying that Redis is 10 times faster than Mongo. That might not be that true anymore. MongoDB (if i remember correctly) claimed to beat memcache for storing and caching documents as long as the memory configurations are the same.

Anyhow. Redis good, MongoDB is good. If you care about substructures and need aggregation go for MongoDB. If storing keys and values is your main concern its all about Redis. (or any other key value store).

JavaScript getElementByID() not working

Because when the script executes the browser has not yet parsed the <body>, so it does not know that there is an element with the specified id.

Try this instead:

<html>
<head>
    <title></title>
    <script type="text/javascript">
        window.onload = (function () {
            var refButton = document.getElementById("btnButton");

            refButton.onclick = function() {
                alert('Dhoor shala!');
            };
        });
    </script>
    </head>
<body>
    <form id="form1">
    <div>
        <input id="btnButton" type="button" value="Click me"/>
    </div>
</form>
</body>
</html>

Note that you may as well use addEventListener instead of window.onload = ... to make that function only execute after the whole document has been parsed.

How to add elements of a string array to a string array list?

In Java 8, the syntax for this simplifies greatly and can be used to accomplish this transformation succinctly.

Do note, you will need to change your field from a concrete implementation to the List interface for this to work smoothly.

public class Wetland {
    private String name;
    private List<String> species;
    public Wetland(String name, String[] speciesArr) {
        this.name = name;
        species = Arrays.stream(speciesArr)
                        .collect(Collectors.toList());
    }
}

Scrolling to element using webdriver?

You are trying to run Java code with Python. In Python/Selenium, the org.openqa.selenium.interactions.Actions are reflected in ActionChains class:

from selenium.webdriver.common.action_chains import ActionChains

element = driver.find_element_by_id("my-id")

actions = ActionChains(driver)
actions.move_to_element(element).perform()

Or, you can also "scroll into view" via scrollIntoView():

driver.execute_script("arguments[0].scrollIntoView();", element)

If you are interested in the differences:

Permission denied (publickey) when SSH Access to Amazon EC2 instance

I'm in Windows with WinSCP. It works great on both File Explorer and PuTTY SSH Shell to access my Amazon EC2-VPC Linux. There is nothing to do with chmod pem file as it uses myfile.ppk converted by PuTTYgen from the pem file.

Checking that a List is not empty in Hamcrest

This is fixed in Hamcrest 1.3. The below code compiles and does not generate any warnings:

// given
List<String> list = new ArrayList<String>();
// then
assertThat(list, is(not(empty())));

But if you have to use older version - instead of bugged empty() you could use:

hasSize(greaterThan(0))
(import static org.hamcrest.number.OrderingComparison.greaterThan; or
import static org.hamcrest.Matchers.greaterThan;)

Example:

// given
List<String> list = new ArrayList<String>();
// then
assertThat(list, hasSize(greaterThan(0)));

The most important thing about above solutions is that it does not generate any warnings. The second solution is even more useful if you would like to estimate minimum result size.

Where are shared preferences stored?

Use http://facebook.github.io/stetho/ library to access your app's local storage with chrome inspect tools. You can find sharedPreference file under Local storage -> < your app's package name >

enter image description here

C++ code file extension? .cc vs .cpp

As with most style conventions, there are only two things that matter:

  1. Be consistent in what you use, wherever possible.
  2. Don't design anything that depends on a specific choice being used.

Those may seem to contradict, but they each have value for their own reasons.

Should I use Python 32bit or Python 64bit

Machine learning packages like tensorflow 2.x are designed to work only on 64 bit Python as they are memory intensive.

How to count digits, letters, spaces for a string in Python?

INPUT :

1

26

sadw96aeafae4awdw2 wd100awd

import re

a=int(input())
for i in range(a):
    b=int(input())
    c=input()

    w=re.findall(r'\d',c)
    x=re.findall(r'\d+',c)
    y=re.findall(r'\s+',c)
    z=re.findall(r'.',c)
    print(len(x))
    print(len(y))
    print(len(z)-len(y)-len(w))

OUTPUT :

4

1

19

The four digits are 96, 4, 2, 100 The number of spaces = 1 number of letters = 19

What are the most common font-sizes for H1-H6 tags

Headings are normally bold-faced; that has been turned off for this demonstration of size correspondence. MSIE and Opera interpret these sizes the same, but note that Gecko browsers and Chrome interpret Heading 6 as 11 pixels instead of 10 pixels/font size 1, and Heading 3 as 19 pixels instead of 18 pixels/font size 4 (though it's difficult to tell the difference even in a direct comparison and impossible in use). It seems Gecko also limits text to no smaller than 10 pixels.

Why was the name 'let' chosen for block-scoped variable declarations in JavaScript?

I guess it follows mathematical tradition. In mathematics, it is often said "let x be arbitrary real number" or like that.

Progress during large file copy (Copy-Item & Write-Progress?)

I amended the code from stej (which was great, just what i needed!) to use larger buffer, [long] for larger files and used System.Diagnostics.Stopwatch class to track elapsed time and estimate time remaining.

Also added reporting of transfer rate during transfer and outputting overall elapsed time and overall transfer rate.

Using 4MB (4096*1024 bytes) buffer to get better than Win7 native throughput copying from NAS to USB stick on laptop over wifi.

On To-Do list:

  • add error handling (catch)
  • handle get-childitem file list as input
  • nested progress bars when copying multiple files (file x of y, % if total data copied etc)
  • input parameter for buffer size

Feel free to use/improve :-)

function Copy-File {
param( [string]$from, [string]$to)
$ffile = [io.file]::OpenRead($from)
$tofile = [io.file]::OpenWrite($to)
Write-Progress `
    -Activity "Copying file" `
    -status ($from.Split("\")|select -last 1) `
    -PercentComplete 0
try {
    $sw = [System.Diagnostics.Stopwatch]::StartNew();
    [byte[]]$buff = new-object byte[] (4096*1024)
    [long]$total = [long]$count = 0
    do {
        $count = $ffile.Read($buff, 0, $buff.Length)
        $tofile.Write($buff, 0, $count)
        $total += $count
        [int]$pctcomp = ([int]($total/$ffile.Length* 100));
        [int]$secselapsed = [int]($sw.elapsedmilliseconds.ToString())/1000;
        if ( $secselapsed -ne 0 ) {
            [single]$xferrate = (($total/$secselapsed)/1mb);
        } else {
            [single]$xferrate = 0.0
        }
        if ($total % 1mb -eq 0) {
            if($pctcomp -gt 0)`
                {[int]$secsleft = ((($secselapsed/$pctcomp)* 100)-$secselapsed);
                } else {
                [int]$secsleft = 0};
            Write-Progress `
                -Activity ($pctcomp.ToString() + "% Copying file @ " + "{0:n2}" -f $xferrate + " MB/s")`
                -status ($from.Split("\")|select -last 1) `
                -PercentComplete $pctcomp `
                -SecondsRemaining $secsleft;
        }
    } while ($count -gt 0)
$sw.Stop();
$sw.Reset();
}
finally {
    write-host (($from.Split("\")|select -last 1) + `
     " copied in " + $secselapsed + " seconds at " + `
     "{0:n2}" -f [int](($ffile.length/$secselapsed)/1mb) + " MB/s.");
     $ffile.Close();
     $tofile.Close();
    }
}

System.Net.WebException: The remote name could not be resolved:

It's probably caused by a local network connectivity issue (but also a DNS error is possible). Unfortunately HResult is generic, however you can determine the exact issue catching HttpRequestException and then inspecting InnerException: if it's a WebException then you can check the WebException.Status property, for example WebExceptionStatus.NameResolutionFailure should indicate a DNS resolution problem.

It may happen, there isn't much you can do.

What I'd suggest to always wrap that (network related) code in a loop with a try/catch block (as also suggested here for other fallible operations). Handle known exceptions, wait a little (say 1000 msec) and try again (for say 3 times). Only if failed all times then you can quit/report an error to your users. Very raw example like this:

private const int NumberOfRetries = 3;
private const int DelayOnRetry = 1000;

public static async Task<HttpResponseMessage> GetFromUrlAsync(string url) {
    using (var client = new HttpClient()) {
        for (int i=1; i <= NumberOfRetries; ++i) {
            try {
                return await client.GetAsync(url); 
            }
            catch (Exception e) when (i < NumberOfRetries) {
                await Task.Delay(DelayOnRetry);
            }
        }
    }
}

Why do people use Heroku when AWS is present? What distinguishes Heroku from AWS?

First things first, AWS and Heroku are different things. AWS offer Infrastructure as a Service (IaaS) whereas Heroku offer a Platform as a Service (PaaS).

What's the difference? Very approximately, IaaS gives you components you need in order to build things on top of it; PaaS gives you an environment where you just push code and some basic configuration and get a running application. IaaS can give you more power and flexibility, at the cost of having to build and maintain more yourself.

To get your code running on AWS and looking a bit like a Heroku deployment, you'll want some EC2 instances - you'll want a load balancer / caching layer installed on them (e.g. Varnish), you'll want instances running something like Passenger and nginx to serve your code, you'll want to deploy and configure a clustered database instance of something like PostgreSQL. You'll want a deployment system with something like Capistrano, and something doing log aggregation.

That's not an insignificant amount of work to set up and maintain. With Heroku, the effort required to get to that sort of stage is maybe a few lines of application code and a git push.

So you're this far, and you want to scale up. Great. You're using Puppet for your EC2 deployment, right? So now you configure your Capistrano files to spin up/down instances as needed; you re-jig your Puppet config so Varnish is aware of web-worker instances and will automatically pool between them. Or you heroku scale web:+5.

Hopefully that gives you an idea of the comparison between the two. Now to address your specific points:

Speed

Currently Heroku only runs on AWS instances in us-east and eu-west. For you, this sounds like what you want anyway. For others, it's potentially more of a consideration.

Security

I've seen a lot of internally-maintained production servers that are way behind on security updates, or just generally poorly put together. With Heroku, you have someone else managing that sort of thing, which is either a blessing or a curse depending on how you look at it!

When you deploy, you're effectively handing your code straight over to Heroku. This may be an issue for you. Their article on Dyno Isolation details their isolation technologies (it seems as though multiple dynos are run on individual EC2 instances). Several colleagues have expressed issues with these technologies and the strength of their isolation; I am alas not in a position of enough knowledge / experience to really comment, but my current Heroku deployments consider that "good enough". It may be an issue for you, I don't know.

Scaling

I touched on how one might implement this in my IaaS vs PaaS comparison above. Approximately, your application has a Procfile, which has lines of the form dyno_type: command_to_run, so for example (cribbed from http://devcenter.heroku.com/articles/process-model):

web:    bundle exec rails server
worker: bundle exec rake jobs:work

This, with a:

heroku scale web:2 worker:10

will result in you having 2 web dynos and 10 worker dynos running. Nice, simple, easy. Note that web is a special dyno type, which has access to the outside world, and is behind their nice web traffic multiplexer (probably some sort of Varnish / nginx combination) that will route traffic accordingly. Your workers probably interact with a message queue for similar routing, from which they'll get the location via a URL in the environment.

Cost Efficiency

Lots of people have lots of different opinions about this. Currently it's $0.05/hr for a dyno hour, compared to $0.025/hr for an AWS micro instance or $0.09/hr for an AWS small instance.

Heroku's dyno documentation says you have about 512MB of RAM, so it's probably not too unreasonable to consider a dyno as a bit like an EC2 micro instance. Is it worth double the price? How much do you value your time? The amount of time and effort required to build on top of an IaaS offering to get it to this standard is definitely not cheap. I can't really answer this question for you, but don't underestimate the 'hidden costs' of setup and maintenance.

(A bit of an aside, but if I connect to a dyno from here (heroku run bash), a cursory look shows 4 cores in /proc/cpuinfo and 36GB of RAM - this leads me to believe that I'm on a "High-Memory Double Extra Large Instance". The Heroku dyno documentation says each dyno receives 512MB of RAM, so I'm potentially sharing with up to 71 other dynos. (I don't have enough data about the homogeny of Heroku's AWS instances, so your milage may vary))

How do they fare against their competitors?

This, I'm afraid I can't really help you with. The only competitor I've ever really looked at was Google App Engine - at the time I was looking to deploy Java applications, and the amount of restrictions on usable frameworks and technologies was incredibly off-putting. This is more than "just a Java thing" - the amount of general restrictions and necessary considerations (the FAQ hints at several) seemed less than convenient. In contrast, deploying to Heroku has been a dream.

Conclusion

I hope this answers your questions (please comment if there are gaps / other areas you'd like addressed). I feel I should offer my personal position. I love Heroku for "quick deployments". When I'm starting an application, and I want some cheap hosting (the Heroku free tier is awesome - essentially if you only need one web dyno and 5MB of PostgreSQL, it's free to host an application), Heroku is my go-to position. For "Serious Production Deployment" with several paying customers, with a service-level-agreement, with dedicated time to spend on ops, et cetera, I can't quite bring myself to offload that much control to Heroku, and then either AWS or our own servers have been the hosting platform of choice.

Ultimately, it's about what works best for you. You say you're "a beginner programmer" - it might just be that using Heroku will let you focus on writing Ruby, and not have to spend time getting all the other infrastructure around your code built up. I'd definitely give it a try.

Note, AWS does actually have a PaaS offering, Elastic Beanstalk, that supports Ruby, Node.js, PHP, Python, .NET and Java. I think generally most people, when they see "AWS", jump to things like EC2 and S3 and EBS, which are definitely IaaS offerings

The specified type member 'Date' is not supported in LINQ to Entities. Only initializers, entity members, and entity navigation properties

Another solution could be:

var eventsCustom = eventCustomRepository.FindAllEventsCustomByUniqueStudentReference(userDevice.UniqueStudentReference).AsEnumerable()
   .Where(x => x.DateTimeStart.Date == currentDate.Date).AsQueryable();

Eclipse: How do I add the javax.servlet package to a project?

When you define a server in server view, then it will create you a server runtime library with server libs (including servlet api), that can be assigned to your project. However, then everybody that uses your project, need to create the same type of runtime in his/her eclipse workspace even for compiling.

If you directly download the servlet api jar, than it could lead to problems, since it will be included into the artifacts of your projects, but will be also present in servlet container.

In Maven it is much nicer, since you can define the servlet api interfaces as a "provided" dependency, that means it is present in the "to be production" environment.