Programs & Examples On #Timsort

Timsort is a sorting algorithm invented by Tim Peters, designed to take advantage of partial ordering in data. It has an average-case complexity of Θ(nlogn) and worst-case complexity of O(nlogn).

Java error: Comparison method violates its general contract

I had the same symptom. For me it turned out that another thread was modifying the compared objects while the sorting was happening in a Stream. To resolve the issue, I mapped the objects to immutable temporary objects, collected the Stream to a temporary Collection and did the sorting on that.

cannot be cast to java.lang.Comparable

  • the object which implements Comparable is Fegan.

The method compareTo you are overidding in it should have a Fegan object as a parameter whereas you are casting it to a FoodItems. Your compareTo implementation should describe how a Fegan compare to another Fegan.

  • To actually do your sorting, you might want to make your FoodItems implement Comparable aswell and copy paste your actual compareTo logic in it.

window.close and self.close do not close the window in Chrome

The below code worked for me -

window.open('location', '_self', '');
window.close();

Tested on Chrome 43.0.2357.81

How to place a file on classpath in Eclipse?

One option is to place your properties file in the src/ directory of your project. This will copy it to the "classes" (along with your .class files) at build time. I often do this for web projects.

Find a string within a cell using VBA

For a search routine you should look to use Find, AutoFilter or variant array approaches. Range loops are nomally too slow, worse again if they use Select

The code below will look for the strText variable in a user selected range, it then adds any matches to a range variable rng2 which you can then further process

Option Explicit

Const strText As String = "%"

Sub ColSearch_DelRows()
    Dim rng1 As Range
    Dim rng2 As Range
    Dim rng3 As Range
    Dim cel1 As Range
    Dim cel2 As Range
    Dim strFirstAddress As String
    Dim lAppCalc As Long


    'Get working range from user
    On Error Resume Next
    Set rng1 = Application.InputBox("Please select range to search for " & strText, "User range selection", Selection.Address(0, 0), , , , , 8)
    On Error GoTo 0
    If rng1 Is Nothing Then Exit Sub

    With Application
        lAppCalc = .Calculation
        .ScreenUpdating = False
        .Calculation = xlCalculationManual
    End With

    Set cel1 = rng1.Find(strText, , xlValues, xlPart, xlByRows, , False)

    'A range variable - rng2 - is used to store the range of cells that contain the string being searched for
    If Not cel1 Is Nothing Then
        Set rng2 = cel1
        strFirstAddress = cel1.Address
        Do
            Set cel1 = rng1.FindNext(cel1)
            Set rng2 = Union(rng2, cel1)
        Loop While strFirstAddress <> cel1.Address
    End If

    If Not rng2 Is Nothing Then
        For Each cel2 In rng2
            Debug.Print cel2.Address & " contained " & strText
        Next
    Else
        MsgBox "No " & strText
    End If

    With Application
        .ScreenUpdating = True
        .Calculation = lAppCalc
    End With

End Sub

Java : Convert formatted xml file to one line string

The above solutions work if you are compressing all white space in the XML document. Other quick options are JDOM (using Format.getCompactFormat()) and dom4j (using OutputFormat.createCompactFormat()) when outputting the XML document.

However, I had a unique requirement to preserve the white space contained within the element's text value and these solutions did not work as I needed. All I needed was to remove the 'pretty-print' formatting added to the XML document.

The solution that I came up with can be explained in the following 3-step/regex process ... for the sake of understanding the algorithm for the solution.

String regex, updatedXml;

// 1. remove all white space preceding a begin element tag:
regex = "[\\n\\s]+(\\<[^/])";
updatedXml = originalXmlStr.replaceAll( regex, "$1" );

// 2. remove all white space following an end element tag:
regex = "(\\</[a-zA-Z0-9-_\\.:]+\\>)[\\s]+";
updatedXml = updatedXml.replaceAll( regex, "$1" );

// 3. remove all white space following an empty element tag
// (<some-element xmlns:attr1="some-value".... />):
regex = "(/\\>)[\\s]+";
updatedXml = updatedXml.replaceAll( regex, "$1" );

NOTE: The pseudo-code is in Java ... the '$1' is the replacement string which is the 1st capture group.

This will simply remove the white space used when adding the 'pretty-print' format to an XML document, yet preserve all other white space when it is part of the element text value.

How to load image (and other assets) in Angular an project?

Angular-cli includes the assets folder in the build options by default. I got this issue when the name of my images had spaces or dashes. For example :

  • 'my-image-name.png' should be 'myImageName.png'
  • 'my image name.png' should be 'myImageName.png'

If you put the image in the assets/img folder, then this line of code should work in your templates :

<img alt="My image name" src="./assets/img/myImageName.png">

If the issue persist just check if your Angular-cli config file and be sure that your assets folder is added in the build options.

The instance of entity type cannot be tracked because another instance of this type with the same key is already being tracked

If your data has changed every once,you will notice dont tracing the table.for example some table update id ([key]) using tigger.If you tracing ,you will get same id and get the issue.

Referencing value in a closed Excel workbook using INDIRECT?

Check INDEX Function:

=INDEX('C:\path\[file.xlsm]Sheet1'!A10:B20;1;1)

Format y axis as percent

Based on the answer of @erwanp, you can use the formatted string literals of Python 3,

x = '2'
percentage = f'{x}%' # 2%

inside the FuncFormatter() and combined with a lambda expression.

All wrapped:

ax.yaxis.set_major_formatter(FuncFormatter(lambda y, _: f'{y}%'))

How to use LogonUser properly to impersonate domain user from workgroup client

It's better to use a SecureString:

var password = new SecureString();
var phPassword phPassword = Marshal.SecureStringToGlobalAllocUnicode(password);
IntPtr phUserToken;
LogonUser(username, domain, phPassword, LOGON32_LOGON_INTERACTIVE,  LOGON32_PROVIDER_DEFAULT, out phUserToken);

And:

Marshal.ZeroFreeGlobalAllocUnicode(phPassword);
password.Dispose();

Function definition:

private static extern bool LogonUser(
  string pszUserName,
  string pszDomain,
  IntPtr pszPassword,
  int dwLogonType,
  int dwLogonProvider,
  out IntPtr phToken);

How can I copy a file on Unix using C?

#include <unistd.h>
#include <string.h>
#include <errno.h>
#include <fcntl.h>
#include <sys/types.h>
#include <sys/stat.h>
#include <stdio.h>

#define    print_err(format, args...)   printf("[%s:%d][error]" format "\n", __func__, __LINE__, ##args)
#define    DATA_BUF_SIZE                (64 * 1024)    //limit to read maximum 64 KB data per time

int32_t get_file_size(const char *fname){
    struct stat sbuf;

    if (NULL == fname || strlen(fname) < 1){
        return 0;
    }

    if (stat(fname, &sbuf) < 0){
        print_err("%s, %s", fname, strerror(errno));
        return 0;
    }

    return sbuf.st_size; /* off_t shall be signed interge types, used for file size */
}

bool copyFile(CHAR *pszPathIn, CHAR *pszPathOut)
{
    INT32 fdIn, fdOut;
    UINT32 ulFileSize_in = 0;
    UINT32 ulFileSize_out = 0;
    CHAR *szDataBuf;

    if (!pszPathIn || !pszPathOut)
    {
        print_err(" Invalid param!");
        return false;
    }

    if ((1 > strlen(pszPathIn)) || (1 > strlen(pszPathOut)))
    {
        print_err(" Invalid param!");
        return false;
    }

    if (0 != access(pszPathIn, F_OK))
    {
        print_err(" %s, %s!", pszPathIn, strerror(errno));
        return false;
    }

    if (0 > (fdIn = open(pszPathIn, O_RDONLY)))
    {
        print_err("open(%s, ) failed, %s", pszPathIn, strerror(errno));
        return false;
    }

    if (0 > (fdOut = open(pszPathOut, O_CREAT | O_WRONLY | O_TRUNC, 0777)))
    {
        print_err("open(%s, ) failed, %s", pszPathOut, strerror(errno));
        close(fdIn);
        return false;
    }

    szDataBuf = malloc(DATA_BUF_SIZE);
    if (NULL == szDataBuf)
    {
        print_err("malloc() failed!");
        return false;
    }

    while (1)
    {
        INT32 slSizeRead = read(fdIn, szDataBuf, sizeof(szDataBuf));
        INT32 slSizeWrite;
        if (slSizeRead <= 0)
        {
            break;
        }

        slSizeWrite = write(fdOut, szDataBuf, slSizeRead);
        if (slSizeWrite < 0)
        {
            print_err("write(, , slSizeRead) failed, %s", slSizeRead, strerror(errno));
            break;
        }

        if (slSizeWrite != slSizeRead) /* verify wheter write all byte data successfully */
        {
            print_err(" write(, , %d) failed!", slSizeRead);
            break;
        }
    }

    close(fdIn);
    fsync(fdOut); /* causes all modified data and attributes to be moved to a permanent storage device */
    close(fdOut);

    ulFileSize_in = get_file_size(pszPathIn);
    ulFileSize_out = get_file_size(pszPathOut);
    if (ulFileSize_in == ulFileSize_out) /* verify again wheter write all byte data successfully */
    {
        free(szDataBuf);
        return true;
    }
    free(szDataBuf);
    return false;
}

Handling Enter Key in Vue.js

In vue 2, You can catch enter event with v-on:keyup.enter check the documentation:

https://vuejs.org/v2/guide/events.html#Key-Modifiers

I leave a very simple example:

_x000D_
_x000D_
var vm = new Vue({_x000D_
  el: '#app',_x000D_
  data: {msg: ''},_x000D_
  methods: {_x000D_
    onEnter: function() {_x000D_
       this.msg = 'on enter event';_x000D_
    }_x000D_
  }_x000D_
});
_x000D_
<script src="https://cdn.jsdelivr.net/npm/vue"></script>_x000D_
_x000D_
<div id="app">_x000D_
  <input v-on:keyup.enter="onEnter" />_x000D_
  <h1>{{ msg }}</h1>_x000D_
</div>
_x000D_
_x000D_
_x000D_

Good luck

using facebook sdk in Android studio

*Gradle Repository for the Facebook SDK.

dependencies {
    compile 'com.facebook.android:facebook-android-sdk:4.4.0'
}

Search for the latest version facebook sdk

Generate an integer that is not among four billion given ones

EDIT Ok, this wasn't quite thought through as it assumes the integers in the file follow some static distribution. Apparently they don't need to, but even then one should try this:


There are ˜4.3 billion 32-bit integers. We don't know how they are distributed in the file, but the worst case is the one with the highest Shannon entropy: an equal distribution. In this case, the probablity for any one integer to not occur in the file is

( (2³²-1)/2³² )4 °°° °°° °°° ˜ .4

The lower the Shannon entropy, the higher this probability gets on the average, but even for this worst case we have a chance of 90% to find a nonoccurring number after 5 guesses with random integers. Just create such numbers with a pseudorandom generator, store them in a list. Then read int after int and compare it to all of your guesses. When there's a match, remove this list entry. After having been through all of the file, chances are you will have more than one guess left. Use any of them. In the rare (10% even at worst case) event of no guess remaining, get a new set of random integers, perhaps more this time (10->99%).

Memory consumption: a few dozen bytes, complexity: O(n), overhead: neclectable as most of the time will be spent in the unavoidable hard disk accesses rather than comparing ints anyway.


The actual worst case, when we do not assume a static distribution, is that every integer occurs max. once, because then only 1 - 4000000000/2³² ˜ 6% of all integers don't occur in the file. So you'll need some more guesses, but that still won't cost hurtful amounts of memory.

Replace only text inside a div using jquery

You need to set the text to something other than an empty string. In addition, the .html() function should do it while preserving the HTML structure of the div.

$('#one').html($('#one').html().replace('text','replace'));

ALTER COLUMN in sqlite

SQLite supports a limited subset of ALTER TABLE. The ALTER TABLE command in SQLite allows the user to rename a table or to add a new column to an existing table. It is not possible to rename a column, remove a column, or add or remove constraints from a table. But you can alter table column datatype or other property by the following steps.

  1. BEGIN TRANSACTION;
  2. CREATE TEMPORARY TABLE t1_backup(a,b);
  3. INSERT INTO t1_backup SELECT a,b FROM t1;
  4. DROP TABLE t1;
  5. CREATE TABLE t1(a,b);
  6. INSERT INTO t1 SELECT a,b FROM t1_backup;
  7. DROP TABLE t1_backup;
  8. COMMIT

For more detail you can refer the link.

Best way to handle list.index(might-not-exist) in python?

I don't know why you should think it is dirty... because of the exception? if you want a oneliner, here it is:

thing_index = thing_list.index(elem) if thing_list.count(elem) else -1

but i would advise against using it; I think Ross Rogers solution is the best, use an object to encapsulate your desiderd behaviour, don't try pushing the language to its limits at the cost of readability.

How to change a package name in Eclipse?

com.myCompany.executabe is the path of executabe package. Here com,myCompany,executable are three different package. You have to manually rename individual package name you want to change.

Disable dragging an image from an HTML page

Great solution, had one small issue with conflicts, If anyone else has conflict from other js library simply enable no conflict like so.

var $j = jQuery.noConflict();$j('img').bind('dragstart', function(event) { event.preventDefault(); });

Hope this helps someone out.

Node.js https pem error: routines:PEM_read_bio:no start line

I removed this error by write the following code

Open Terminal

  1. openssl req -newkey rsa:2048 -new -nodes -keyout key.pem -out csr.pem

  2. openssl x509 -req -days 365 -in csr.pem -signkey key.pem -out server.crt

Now use the server.crt and key.pem file

app.js or server.js file

var https = require('https');
var https_options = {
  key: fs.readFileSync('key.pem', 'utf8'),
  cert: fs.readFileSync('server.crt', 'utf8')
};

var server = https.createServer(https_options, app).listen(PORT);
console.log('HTTPS Server listening on %s:%s', HOST, PORT);

It works but the certificate is not trusted. You can view the image in image file.

enter image description here

Generator expressions vs. list comprehensions

I'm using the Hadoop Mincemeat module. I think this is a great example to take a note of:

import mincemeat

def mapfn(k,v):
    for w in v:
        yield 'sum',w
        #yield 'count',1


def reducefn(k,v): 
    r1=sum(v)
    r2=len(v)
    print r2
    m=r1/r2
    std=0
    for i in range(r2):
       std+=pow(abs(v[i]-m),2)  
    res=pow((std/r2),0.5)
    return r1,r2,res

Here the generator gets numbers out of a text file (as big as 15GB) and applies simple math on those numbers using Hadoop's map-reduce. If I had not used the yield function, but instead a list comprehension, it would have taken a much longer time calculating the sums and average (not to mention the space complexity).

Hadoop is a great example for using all the advantages of Generators.

Facebook share link - can you customize the message body text?

To add some text, what I did some time ago , if the link you are sharing its a page you can modify. You can add some meta-tags to the shared page:

<meta name="title" content="The title you want" />
<meta name="description" content="The text you want to insert " />
<link rel="image_src" href="A thumbnail you can show" / >

It's a small hack. Although the old share button has been replaced by the "like"/"recommend" button where you can add a comment if you use the XFBML version. More info her:

http://developers.facebook.com/docs/reference/plugins/like/

Python: Convert timedelta to int in a dataframe

The simplest way to do this is by

df["DateColumn"] = (df["DateColumn"]).dt.days

Refused to display 'url' in a frame because it set 'X-Frame-Options' to 'SAMEORIGIN'

I was facing this issue in Grafana and all I had to do was go to the config file and change allow_embedding to true and restart the server :)

Styling the arrow on bootstrap tooltips

You can always try putting this code in your main css without modifying the bootstrap file what is most recommended so you keep consistency if in a future you update the bootstrap file.

.tooltip-inner {
background-color: #FF0000;
}

.tooltip.right .tooltip-arrow {
border-right: 5px solid #FF0000;

}

Notice that this example is for a right tooltip. The tooltip-inner property changes the tooltip BG color, the other one changes the arrow color.

How to search all loaded scripts in Chrome Developer Tools?

In Windows Control+Shift+F. Also make sure to search in content scripts as well. Go to Settings->Sources-> Search in anonymous and content script.

Logging in Scala

Logging in 2020

I was really surprised that Scribe logging framework that I use at work isn't even mentioned here. What is more, it doesn't even appear on the first page in Google after searching "scala logging". But this page appears when googling it! So let me leave that here.

Main advantages of Scribe:

bootstrap initially collapsed element

If removing the in class doesn't work for you, such was my case, you can force the collapsed initial state using the CSS display property:

...
<div id="collapseOne" class="accordion-body collapse" style="display: none;">
...

How to split a comma-separated string?

A small improvement: above solutions will not remove leading or trailing spaces in the actual String. It's better to call trim before calling split. Instead of this,

 String[] animalsArray = animals.split("\\s*,\\s*");

use

 String[] animalsArray = animals.trim().split("\\s*,\\s*");

Attach the Java Source Code

Just remove the JRE in Preferences>Java>Installed JRE and add the folder of your JDK. If you just add JDK but still leave JRE it won't work

How to apply filters to *ngFor?

You could also use the following:

<template ngFor let-item [ngForOf]="itemsList">
    <div *ng-if="conditon(item)"></div>
</template>

This will only show the div if your items matches the condition

See the angular documentation for more information If you would also need the index, use the following:

<template ngFor let-item [ngForOf]="itemsList" let-i="index">
    <div *ng-if="conditon(item, i)"></div>
</template>

Finding and removing non ascii characters from an Oracle Varchar2

I had a similar issue and blogged about it here. I started with the regular expression for alpha numerics, then added in the few basic punctuation characters I liked:

select dump(a,1016), a, b
from
 (select regexp_replace(COLUMN,'[[:alnum:]/''%()> -.:=;[]','') a,
         COLUMN b
  from TABLE)
where a is not null
order by a;

I used dump with the 1016 variant to give out the hex characters I wanted to replace which I could then user in a utl_raw.cast_to_varchar2.

Passing Arrays to Function in C++

I just wanna add this, when you access the position of the array like

arg[n]

is the same as

*(arg + n) than means an offset of n starting from de arg address.

so arg[0] will be *arg

OpenSSL: unable to verify the first certificate for Experian URL

The first error message is telling you more about the problem:

verify error:num=20:unable to get local issuer certificate

The issuing certificate authority of the end entity server certificate is

VeriSign Class 3 Secure Server CA - G3

Look closely in your CA file - you will not find this certificate since it is an intermediary CA - what you found was a similar-named G3 Public Primary CA of VeriSign.

But why does the other connection succeed, but this one doesn't? The problem is a misconfiguration of the servers (see for yourself using the -debug option). The "good" server sends the entire certificate chain during the handshake, therefore providing you with the necessary intermediate certificates.

But the server that is failing sends you only the end entity certificate, and OpenSSL is not capable of downloading the missing intermediate certificate "on the fly" (which would be possible by interpreting the Authority Information Access extension). Therefore your attempt fails using s_client but it would succeed nevertheless if you browse to the same URL using e.g. FireFox (which does support the "certificate discovery" feature).

Your options to solve the problem are either fixing this on the server side by making the server send the entire chain, too, or by passing the missing intermediate certificate to OpenSSL as a client-side parameter.

How to get root view controller?

Objective-C

UIViewController *controller = [UIApplication sharedApplication].keyWindow.rootViewController;

Swift 2.0

let viewController = UIApplication.sharedApplication().keyWindow?.rootViewController

Swift 5

let viewController = UIApplication.shared.keyWindow?.rootViewController

Is it possible to have empty RequestParam values use the defaultValue?

You can also do something like this -

 @RequestParam(value= "i", defaultValue = "20") Optional<Integer> i

What's the difference between .NET Core, .NET Framework, and Xamarin?

.NET Core is the current version of .NET that you should be using right now (more features , fixed bugs , etc.)

Xamarin is a platform that provides solutions for cross platform mobile problems coded in C# , so that you don't need to use Swift separately for IOS and the same goes for Android.

#ifdef replacement in the Swift language

In Swift projects created with Xcode Version 9.4.1, Swift 4.1

#if DEBUG
#endif

works by default because in the Preprocessor Macros DEBUG=1 has already been set by Xcode.

So you can use #if DEBUG "out of box".

By the way, how to use the condition compilation blocks in general is written in Apple's book The Swift Programming Language 4.1 (the section Compiler Control Statements) and how to write the compile flags and what is counterpart of the C macros in Swift is written in another Apple's book Using Swift with Cocoa and Objective C (in the section Preprocessor Directives)

Hope in future Apple will write the more detailed contents and the indexes for their books.

How to get css background color on <tr> tag to span entire row

This worked for me, even within a div:

      div.cntrblk tr:hover td {
        line-height: 150%;
        background-color: rgb(255,0,0);
        font-weight: bold;
        font-size: 150%;
        border: 0;
      }

It selected the entire row, but I'd like it to not do the header, haven't looked at that yet. It also partially fixed the fonts that wouldn't scale-up with the hover??? Apparently you to have apply settings to the cell not the row, but select all the component cells with the tr:hover. On to tracking down the in-consistent font scaling problem. Sweet that CSS will do this.

Socket File "/var/pgsql_socket/.s.PGSQL.5432" Missing In Mountain Lion (OS X Server)

check the postgres server is running with following code

sudo service postgresql status

if the postgres server is inactive, write the following command.

sudo service postgresql start

How to enable CORS in flask

Here is what worked for me when I deployed to Heroku.

http://flask-cors.readthedocs.org/en/latest/
Install flask-cors by running - pip install -U flask-cors

from flask import Flask
from flask_cors import CORS, cross_origin
app = Flask(__name__)
cors = CORS(app)
app.config['CORS_HEADERS'] = 'Content-Type'

@app.route("/")
@cross_origin()
def helloWorld():
  return "Hello, cross-origin-world!"

How to insert current datetime in postgresql insert query

timestamp (or date or time columns) do NOT have "a format".

Any formatting you see is applied by the SQL client you are using.


To insert the current time use current_timestamp as documented in the manual:

INSERT into "Group" (name,createddate) 
VALUES ('Test', current_timestamp);

To display that value in a different format change the configuration of your SQL client or format the value when SELECTing the data:

select name, to_char(createddate, ''yyyymmdd hh:mi:ss tt') as created_date
from "Group"

For psql (the default command line client) you can configure the display format through the configuration parameter DateStyle: https://www.postgresql.org/docs/current/static/runtime-config-client.html#GUC-DATESTYLE

Stopword removal with NLTK

I suggest you create your own list of operator words that you take out of the stopword list. Sets can be conveniently subtracted, so:

operators = set(('and', 'or', 'not'))
stop = set(stopwords...) - operators

Then you can simply test if a word is in or not in the set without relying on whether your operators are part of the stopword list. You can then later switch to another stopword list or add an operator.

if word.lower() not in stop:
    # use word

Read .mat files in Python

Having MATLAB 2014b or newer installed, the MATLAB engine for Python could be used:

import matlab.engine
eng = matlab.engine.start_matlab()
content = eng.load("example.mat", nargout=1)

How to create timer in angular2

I faced a problem that I had to use a timer, but I had to display them in 2 component same time, same screen. I created the timerObservable in a service. I subscribed to the timer in both component, and what happened? It won't be synched, cause new subscription always creates its own stream.

What I would like to say, is that if you plan to use one timer at several places, always put .publishReplay(1).refCount() at the end of the Observer, cause it will publish the same stream out of it every time.

Example:

this.startDateTimer = Observable.combineLatest(this.timer, this.startDate$, (localTimer, startDate) => {
  return this.calculateTime(startDate);
}).publishReplay(1).refCount();

How to use refs in React with Typescript

I always do this, in that case to grab a ref

let input: HTMLInputElement = ReactDOM.findDOMNode<HTMLInputElement>(this.refs.input);

I have 2 dates in PHP, how can I run a foreach loop to go through all of those days?

User this function:-

function dateRange($first, $last, $step = '+1 day', $format = 'Y-m-d' ) {
                $dates = array();
                $current = strtotime($first);
                $last = strtotime($last);

                while( $current <= $last ) {    
                    $dates[] = date($format, $current);
                    $current = strtotime($step, $current);
                }
                return $dates;
        }

Usage / function call:-

Increase by one day:-

dateRange($start, $end); //increment is set to 1 day.

Increase by Month:-

dateRange($start, $end, "+1 month");//increase by one month

use third parameter if you like to set date format:-

   dateRange($start, $end, "+1 month", "Y-m-d H:i:s");//increase by one month and format is mysql datetime

Passing command line arguments from Maven as properties in pom.xml

Inside pom.xml

<project>

.....

<profiles>
    <profile>
        <id>linux64</id>
        <activation>
            <activeByDefault>true</activeByDefault>
        </activation>
        <properties>
            <build_os>linux</build_os>
            <build_ws>gtk</build_ws>
            <build_arch>x86_64</build_arch>
        </properties>
    </profile>

    <profile>
        <id>win64</id>
        <activation>
            <property>
                <name>env</name>
                <value>win64</value>
            </property>
        </activation>
        <properties>
            <build_os>win32</build_os>
            <build_ws>win32</build_ws>
            <build_arch>x86_64</build_arch>
        </properties>
    </profile>
</profiles>

.....

<plugin>
    <groupId>org.eclipse.tycho</groupId>
    <artifactId>target-platform-configuration</artifactId>
    <version>${tycho.version}</version>
    <configuration>
        <environments>
            <environment>
                <os>${build_os}</os>
                <ws>${build_ws}</ws>
                <arch>${build_arch}</arch>
            </environment>
        </environments>
    </configuration>
</plugin>

.....

In this example when you run the pom without any argument mvn clean install default profile will execute.

When executed with mvn -Denv=win64 clean install

win64 profile will executed.

Please refer http://maven.apache.org/guides/introduction/introduction-to-profiles.html

Why does Vim save files with a ~ extension?

:set nobackup 

will turn off backups. You can also set a backupdir if you still want those backup files but in a central folder. This way your working dir is not littered with ~ files.

You find more information on backups under :he backup.

jQuery see if any or no checkboxes are selected

You can use something like this

if ($("#formID input:checkbox:checked").length > 0)
{
    // any one is checked
}
else
{
   // none is checked
}

how to configure config.inc.php to have a loginform in phpmyadmin

$cfg['Servers'][$i]['auth_type'] = 'cookie';

should work.

From the manual:

auth_type = 'cookie' prompts for a MySQL username and password in a friendly HTML form. This is also the only way by which one can log in to an arbitrary server (if $cfg['AllowArbitraryServer'] is enabled). Cookie is good for most installations (default in pma 3.1+), it provides security over config and allows multiple users to use the same phpMyAdmin installation. For IIS users, cookie is often easier to configure than http.

Parsing JSON using Json.net

(This question came up high on a search engine result, but I ended up using a different approach. Adding an answer to this old question in case other people with similar questions read this)

You can solve this with Json.Net and make an extension method to handle the items you want to loop:

public static Tuple<string, int, int> ToTuple(this JToken token)
{
    var type = token["attributes"]["OBJECT_TYPE"].ToString();
    var x = token["position"]["x"].Value<int>();
    var y = token["position"]["y"].Value<int>();
    return new Tuple<string, int, int>(type, x, y);
}

And then access the data like this: (scenario: writing to console):

var tuples = JObject.Parse(myJsonString)["objects"].Select(item => item.ToTuple()).ToList();
tuples.ForEach(t => Console.WriteLine("{0}: ({1},{2})", t.Item1, t.Item2, t.Item3));

How to get query parameters from URL in Angular 5?

import { ParamMap, Router, ActivatedRoute } from '@angular/router';

constructor(private route: ActivatedRoute) {}

ngOnInit() {
    console.log(this.route.snapshot.queryParamMap);
}

UPDATE

import { Router, RouterStateSnapshot } from '@angular/router';

export class LoginComponent {
    constructor(private router: Router) {
        const snapshot: RouterStateSnapshot = router.routerState.snapshot;
        console.log(snapshot);  // <-- hope it helps
    }
}

How to avoid using Select in Excel VBA

One small point of emphasis I'll add to all the excellent answers given previously:

Probably the biggest thing you can do to avoid using Select is to as much as possible, use named ranges (combined with meaningful variable names) in your VBA code. This point was mentioned above, but it was glossed over a bit; however, it deserves special attention.

Here are a couple of additional reasons to make liberal use of named ranges, though I am sure I could think of more.

Named ranges make your code easier to read and understand.

Example:

Dim Months As Range
Dim MonthlySales As Range

Set Months = Range("Months")
' E.g, "Months" might be a named range referring to A1:A12

Set MonthlySales = Range("MonthlySales")
' E.g, "Monthly Sales" might be a named range referring to B1:B12

Dim Month As Range
For Each Month in Months
    Debug.Print MonthlySales(Month.Row)
Next Month

It is pretty obvious what the named ranges Months and MonthlySales contain, and what the procedure is doing.

Why is this important? Partially because it is easier for other people to understand it, but even if you are the only person who will ever see or use your code, you should still use named ranges and good variable names because you will forget what you meant to do with it a year later, and you will waste 30 minutes just figuring out what your code is doing.

Named ranges ensure that your macros do not break when (not if!) the configuration of the spreadsheet changes.

Consider, if the above example had been written like this:

Dim rng1 As Range
Dim rng2 As Range

Set rng1 = Range("A1:A12")
Set rng2 = Range("B1:B12")

Dim rng3 As Range
For Each rng3 in rng1
    Debug.Print rng2(rng3.Row)
Next rng3

This code will work just fine at first - that is until you or a future user decides "gee wiz, I think I'm going to add a new column with the year in Column A!", or put an expenses column between the months and sales columns, or add a header to each column. Now, your code is broken. And because you used terrible variable names, it will take you a lot more time to figure out how to fix it than it should take.

If you had used named ranges to begin with, the Months and Sales columns could be moved around all you like, and your code would continue working just fine.

XML serialization in Java?

If you're talking about automatic XML serialization of objects, check out Castor:

Castor is an Open Source data binding framework for Java[tm]. It's the shortest path between Java objects, XML documents and relational tables. Castor provides Java-to-XML binding, Java-to-SQL persistence, and more.

Angular and debounce

We can create a [debounce] directive which overwrites ngModel's default viewToModelUpdate function with an empty one.

Directive Code

@Directive({ selector: '[debounce]' })
export class MyDebounce implements OnInit {
    @Input() delay: number = 300;

    constructor(private elementRef: ElementRef, private model: NgModel) {
    }

    ngOnInit(): void {
        const eventStream = Observable.fromEvent(this.elementRef.nativeElement, 'keyup')
            .map(() => {
                return this.model.value;
            })
            .debounceTime(this.delay);

        this.model.viewToModelUpdate = () => {};

        eventStream.subscribe(input => {
            this.model.viewModel = input;
            this.model.update.emit(input);
        });
    }
}

How to use it

<div class="ui input">
  <input debounce [delay]=500 [(ngModel)]="myData" type="text">
</div>

Hide div by default and show it on click with bootstrap

Here I propose a way to do this exclusively using the Bootstrap framework built-in functionality.

  1. You need to make sure the target div has an ID.
  2. Bootstrap has a class "collapse", this will hide your block by default. If you want your div to be collapsible AND be shown by default you need to add "in" class to the collapse. Otherwise the toggle behavior will not work properly.
  3. Then, on your hyperlink (also works for buttons), add an href attribute that points to your target div.
  4. Finally, add the attribute data-toggle="collapse" to instruct Bootstrap to add an appropriate toggle script to this tag.

Here is a code sample than can be copy-pasted directly on a page that already includes Bootstrap framework (up to version 3.4.1):

<a href="#Foo" class="btn btn-default" data-toggle="collapse">Toggle Foo</a>
<button href="#Bar" class="btn btn-default" data-toggle="collapse">Toggle Bar</button>
<div id="Foo" class="collapse">
    This div (Foo) is hidden by default
</div>
<div id="Bar" class="collapse in">
    This div (Bar) is shown by default and can toggle
</div>

Postgresql: error "must be owner of relation" when changing a owner object

Thanks to Mike's comment, I've re-read the doc and I've realised that my current user (i.e. userA that already has the create privilege) wasn't a direct/indirect member of the new owning role...

So the solution was quite simple - I've just done this grant:

grant userB to userA;

That's all folks ;-)


Update:

Another requirement is that the object has to be owned by user userA before altering it...

How to call Stored Procedures with EntityFramework?

This is an example of querying MySQL procedure using Entity Framework

This is the definition of my Stored Procedure in MySQL:

CREATE PROCEDURE GetUpdatedAds (
    IN curChangeTracker BIGINT
    IN PageSize INT
) 
BEGIN
   -- select some recored...
END;

And this is how I query it using Entity Framework:

 var curChangeTracker = new SqlParameter("@curChangeTracker", MySqlDbType.Int64).Value = 0;
 var pageSize = new SqlParameter("@PageSize", (MySqlDbType.Int64)).Value = 100;

 var res = _context.Database.SqlQuery<MyEntityType>($"call GetUpdatedAds({curChangeTracker}, {pageSize})");

Note that I am using C# String Interpolation to build my Query String.

How to use View.OnTouchListener instead of onClick

OnClick is triggered when the user releases the button. But if you still want to use the TouchListener you need to add it in code. It's just:

myView.setOnTouchListener(new View.OnTouchListener()
{
    // Implementation;
});

How do I start PowerShell from Windows Explorer?

In Windows Explorer, just go to the Address Bar at the top (keyboard shortcuts: Alt+D or Ctrl+L) and type powershell or powershell_ise and press Enter. A PowerShell command window opens with the current directory.

What is the best way to programmatically detect porn images?

I shall not today attempt further to define the kinds of material I understand to be embraced within that shorthand description ["hard-core pornography"]; and perhaps I could never succeed in intelligibly doing so. But I know it when I see it, and the motion picture involved in this case is not that.

United States Supreme Court Justice Potter Stewart, 1964

C++ Remove new line from multiline string

You should use the erase-remove idiom, looking for '\n'. This will work for any standard sequence container; not just string.

Can a PDF file's print dialog be opened with Javascript?

I use named action instead of javascript because javascript often is disabled, and if it isn't it gives a warning.

My web application creates a postscript file that then is converted with ghostscript to a pdf. I want it to print automatically because the user has already clicked on print inside my application. With the information about named actions from @DSimon above, I researched how to solve this. It all boils down to insert the string /Type /Action /S /Named /N /Print at the right place in the pdf.

I was thinking of writing a small utility, but it has to parse the pdf to find the root node, insert /OpenAction with a reference an object with the action, and recalculate the byte-offsets in xref.

But then I found out about pdfmark which is an extension to postscript to express, in postscript syntax, idioms that are converted to pdf by Adobes distiller or by ghostscript.

Since I'm already using ghostscript, all I have to do is append the following to the end of my postscript file:

%AUTOPRINT
[ /_objdef {PrintAction} /type /dict /OBJ pdfmark
[ {PrintAction} << /Type /Action /S /Named /N /Print >> /PUT pdfmark
[ {Catalog} << /OpenAction {PrintAction} >> /PUT pdfmark

and ghostscript will create the action, link it, and calculate the xref offsets. (In postscript % is a comment and PrintAction is my name for the object)

By looking at the PDF I see that it has created this:

1 0 obj
<</Type /Catalog /Pages 3 0 R
/OpenAction  9 0 R
/Metadata 10 0 R
>>
endobj

9 0 obj
<</S/Named
/Type/Action
/N/Print>>endobj

1 0 is object 1, revision 0, and 9 0 is object 9, revision 0. In the pdf-trailer is says that it is object 1 that is the root node. As you can see there is a reference from object 1, /OpenAction to run object 9 revision 0.

With ghostscript it's possible to convert a pdf to postscript (pdf2ps), append the text above, and convert it back to pdf with ps2pdf. It should be noted that meta-information about the pdf is lost in this conversion. I haven't searched more into this.

TimePicker Dialog from clicking EditText

I dont know if this will work for you, it works for me just fine.

Create a method for the Date/Time picker dialog.

private DatePickerDialog.OnDateSetListener datePickerListener = new DatePickerDialog.OnDateSetListener() {

    // when dialog box is called, below method will be called.
    // The arguments will be working to get the Day of Week to show it in a special TextView for it.

    public void onDateSet(DatePicker view, int selectedYear,
                          int selectedMonth, int selectedDay) {
        String year1 = String.valueOf(selectedYear);
        String month1 = String.valueOf(selectedMonth + 1);
        String day1 = String.valueOf(selectedDay);
        delivDate.setText(month1 + "/" + day1 + "/" + year1);
        delivDay.setText(DateFormat.format("EEEE", new Date(selectedYear, selectedMonth, selectedDay - 1)).toString());
    }
};

and then, wherever you want you can do it just like this

public void setDateOnClick (View view) {
    Calendar cal = Calendar.getInstance();

    DatePickerDialog datePicker = new DatePickerDialog(this, datePickerListener,
            cal.get(Calendar.YEAR),
            cal.get(Calendar.MONTH),
            cal.get(Calendar.DAY_OF_MONTH));
    //Create a cancel button and set the title of the dialog.
    datePicker.setCancelable(false);
    datePicker.setTitle("Select the date");
    datePicker.show();
}

hope you find this as your solution.

"Unable to find remote helper for 'https'" during git clone

worked

1- I had to remove git:

sudo apt-get remove git

2- re - install git with the -all suffix:

sudo apt-get install git-all

as taught here: https://git-scm.com/book/en/v2/Getting-Started-Installing-Git

3- checked all settings (user name & email) of my github account

by the way I was mistaken the good email which was the source of my errors ;) https://github.com/settings/profile
check your username
https://github.com/settings/emails
check your email is the good one

4- I have followed the tutorial of git here

https://help.github.com/articles/connecting-to-github-with-ssh

CSS Layout - Dynamic width DIV

This will do what you want. Fixed sides with 50px-width, and the content fills the remaining area.

<div style="width:100%;">
    <div style="width: 50px; float: left;">Left Side</div>
    <div style="width: 50px; float: right;">Right Side</div>
    <div style="margin-left: 50px; margin-right: 50px;">Content Goes Here</div>
</div>

How to use SqlClient in ASP.NET Core?

Try this one Open your projectname.csproj file its work for me.

<PackageReference Include="System.Data.SqlClient" Version="4.6.0" />

You need to add this Reference "ItemGroup" tag inside.

How to delete all files and folders in a directory?

It's not the best way to deal with the issue above. But it's an alternative one...

while (Directory.GetDirectories(dirpath).Length > 0)
 {
       //Delete all files in directory
       while (Directory.GetFiles(Directory.GetDirectories(dirpath)[0]).Length > 0)
       {
            File.Delete(Directory.GetFiles(dirpath)[0]);
       }
       Directory.Delete(Directory.GetDirectories(dirpath)[0]);
 }

What is the "assert" function?

C++11 N3337 standard draft

http://www.open-std.org/jtc1/sc22/wg21/docs/papers/2012/n3337.pdf

19.3 Assertions

1 The header <cassert>, described in (Table 42), provides a macro for documenting C ++ program assertions and a mechanism for disabling the assertion checks.

2 The contents are the same as the Standard C library header <assert.h>.

C99 N1256 standard draft

http://www.open-std.org/JTC1/SC22/WG14/www/docs/n1256.pdf

7.2 Diagnostics <assert.h>

1 The header <assert.h> defines the assert macro and refers to another macro, NDEBUG which is not defined by <assert.h>. If NDEBUG is defined as a macro name at the point in the source file where <assert.h> is included, the assert macro is defined simply as

 #define assert(ignore) ((void)0)

The assert macro is redefined according to the current state of NDEBUG each time that <assert.h> is included.

2. The assert macro shall be implemented as a macro, not as an actual function. If the macro definition is suppressed in order to access an actual function, the behavior is undefined.

7.2.1 Program diagnostics

7.2.1.1 The assert macro

Synopsis

1.

#include <assert.h>
void assert(scalar expression);

Description

2 The assert macro puts diagnostic tests into programs; it expands to a void expression. When it is executed, if expression (which shall have a scalar type) is false (that is, compares equal to 0), the assert macro writes information about the particular call that failed (including the text of the argument, the name of the source file, the source line number, and the name of the enclosing function — the latter are respectively the values of the preprocessing macros __FILE__ and __LINE__ and of the identifier __func__) on the standard error stream in an implementation-defined format. 165) It then calls the abort function.

Returns

3 The assert macro returns no value.

How do you change video src using jQuery?

I would rather make it like this

<video  id="v1" width="320" height="240" controls="controls">

</video>

and then use

$("#v1").html('<source src="test1.mp4" type="video/mp4"></source>' );

Convert String to Date in MS Access Query

In Access, click Create > Module and paste in the following code

Public Function ConvertMyStringToDateTime(strIn As String) As Date
ConvertMyStringToDateTime = CDate( _
        Mid(strIn, 1, 4) & "-" & Mid(strIn, 5, 2) & "-" & Mid(strIn, 7, 2) & " " & _
        Mid(strIn, 9, 2) & ":" & Mid(strIn, 11, 2) & ":" & Mid(strIn, 13, 2))
End Function

Hit Ctrl+S and save the module as modDateConversion.

Now try using a query like

Select * from Events
Where Events.[Date] > ConvertMyStringToDateTime("20130423014854")

--- Edit ---

Alternative solution avoiding user-defined VBA function:

SELECT * FROM Events
WHERE Format(Events.[Date],'yyyyMMddHhNnSs') > '20130423014854'

How to get the last row of an Oracle a table

select * from table_name ORDER BY primary_id DESC FETCH FIRST 1 ROWS ONLY;

That's the simplest one without doing sub queries

Converting an OpenCV Image to Black and White

Here's a two line code I found online that might be helpful for a beginner

# Absolute value of the 32/64
abs_image_in32_64 = np.absolute(image_in32_64)

image_8U = np.uint8(abs_image_in32_64)

The CodeDom provider type "Microsoft.CodeDom.Providers.DotNetCompilerPlatform.CSharpCodeProvider" could not be located

It stopped after publishing on the production server. The reason why it showed me this error was because it was deployed to a subfolder. In IIS i clicked right on the subfolder and excuted "Convert to application" and after this it worked.

2D array values C++

One alternative is to represent your 2D array as a 1D array. This can make element-wise operations more efficient. You should probably wrap it in a class that would also contain width and height.

Another alternative is to represent a 2D array as an std::vector<std::vector<int> >. This will let you use STL's algorithms for array arithmetic, and the vector will also take care of memory management for you.

How to fix the "java.security.cert.CertificateException: No subject alternative names present" error?

I fixed this issue in a right way by adding the subject alt names in certificate rather than making any changes in code or disabling SSL unlike what other answers suggest here. If you see clearly the exception says the "Subject alt names are missing" so the right way should be to add them

Please look at this link to understand step by step.

The above error means that your JKS file is missing the required domain on which you are trying to access the application.You will need to Use Open SSL and the key tool to add multiple domains

  1. Copy the openssl.cnf into a current directory
  2. echo '[ subject_alt_name ]' >> openssl.cnf
  3. echo 'subjectAltName = DNS:example.mydomain1.com, DNS:example.mydomain2.com, DNS:example.mydomain3.com, DNS: localhost'>> openssl.cnf
  4. openssl req -x509 -nodes -newkey rsa:2048 -config openssl.cnf -extensions subject_alt_name -keyout private.key -out self-signed.pem -subj '/C=gb/ST=edinburgh/L=edinburgh/O=mygroup/OU=servicing/CN=www.example.com/[email protected]' -days 365
  5. Export the public key (.pem) file to PKS12 format. This will prompt you for password

    openssl pkcs12 -export -keypbe PBE-SHA1-3DES -certpbe PBE-SHA1-3DES -export -in
    self-signed.pem -inkey private.key -name myalias -out keystore.p12
    
  6. Create a.JKS from self-signed PEM (Keystore)

    keytool -importkeystore -destkeystore keystore.jks -deststoretype PKCS12 -srcstoretype PKCS12 -srckeystore keystore.p12
    
  7. Generate a Certificate from above Keystore or JKS file

    keytool -export -keystore keystore.jks -alias myalias -file selfsigned.crt
    
  8. Since the above certificate is Self Signed and is not validated by CA, it needs to be added in Truststore(Cacerts file in below location for MAC, for Windows, find out where your JDK is installed.)

    sudo keytool -importcert -file selfsigned.crt -alias myalias -keystore /Library/Java/JavaVirtualMachines/jdk1.8.0_171.jdk/Contents/Home/jre/lib/security/cacerts
    

Original answer posted on this link here.

Getting the first and last day of a month, using a given DateTime object

The accepted answer here does not take into account the Kind of the DateTime instance. For example if your original DateTime instance was a UTC Kind then by making a new DateTime instance you will be making an Unknown Kind instance which will then be treated as local time based on server settings. Therefore the more proper way to get the first and last date of the month would be this:

var now = DateTime.UtcNow;
var first = now.Date.AddDays(-(now.Date.Day - 1));
var last = first.AddMonths(1).AddTicks(-1);

This way the original Kind of the DateTime instance is preserved.

How do I fix a Git detached head?

If you made changes and then realized that you are on a detached head, you can do: stash -> checkout master -> stash pop:

git stash
git checkout master   # Fix the detached head state
git stash pop         # Or for extra safety use 'stash apply' then later 
                      #   after fixing everything do 'stash drop'

You will have your uncommited changes and normal "attached" HEAD, like nothing happened.

Learning Ruby on Rails

Some awesome advice here!

Some of the resources I will list have been mentioned, some I don't think were. I am definitely still not a pro, I've just been learning for the past few months and I've been improving at a rapid rate. This is what helped me in order:

  1. Why's poignant guide to ruby: excellent introduction to the Ruby language by the infamous _why.
  2. Agile web development with rails book: great book with some good in-depth follow alongs
  3. Rails tutorial by Michael Hartl (railstutotrial.org): this has been my favorite resource. Hartl's style of walking you through demo apps and explaining everything just made things click for me.
  4. Rails for Zombies - ran through this twice, great for reinforcing the basics.
  5. Railscasts - I started following this along at first, but they were not helpful until now that I am just really starting to grasp Rails. I would leave these for the end after you have got your feet wet.
  6. Think Vitamin's rails tutorials were also pretty good. I followed along these screen casts at first, to feel out the language and then did them again towards the end.
  7. The "Learning Rails" podcast, although outdated (Rails 2) was also a good starting resource. I listened to this while driving/working out.

I hope that was helpful! I'm far from being a pro, but I dove in head first and absorbed as much as I could from multiple resources. The ones I mentioned above were the most helpful!

Oh and what's really helping me now is coming up with personal projects and settings certain tasks. Following along is great, but you truly learn when you dive in without a guide!

How do I convert from a string to an integer in Visual Basic?

Use

Convert.toInt32(txtPrice.Text)

This is assuming VB.NET.

Judging by the name "txtPrice", you really don't want an Integer but a Decimal. So instead use:

Convert.toDecimal(txtPrice.Text)

If this is the case, be sure whatever you assign this to is Decimal not an Integer.

Accessing member of base class

You are incorrectly using the super and this keyword. Here is an example of how they work:

class Animal {
    public name: string;
    constructor(name: string) { 
        this.name = name;
    }
    move(meters: number) {
        console.log(this.name + " moved " + meters + "m.");
    }
}

class Horse extends Animal {
    move() {
        console.log(super.name + " is Galloping...");
        console.log(this.name + " is Galloping...");
        super.move(45);
    }
}

var tom: Animal = new Horse("Tommy the Palomino");

Animal.prototype.name = 'horseee'; 

tom.move(34);
// Outputs:

// horseee is Galloping...
// Tommy the Palomino is Galloping...
// Tommy the Palomino moved 45m.

Explanation:

  1. The first log outputs super.name, this refers to the prototype chain of the object tom, not the object tom self. Because we have added a name property on the Animal.prototype, horseee will be outputted.
  2. The second log outputs this.name, the this keyword refers to the the tom object itself.
  3. The third log is logged using the move method of the Animal base class. This method is called from Horse class move method with the syntax super.move(45);. Using the super keyword in this context will look for a move method on the prototype chain which is found on the Animal prototype.

Remember TS still uses prototypes under the hood and the class and extends keywords are just syntactic sugar over prototypical inheritance.

how to insert value into DataGridView Cell?

int index= datagridview.rows.add();
datagridview.rows[index].cells[1].value=1;
datagridview.rows[index].cells[2].value="a";
datagridview.rows[index].cells[3].value="b";

hope this help! :)

horizontal scrollbar on top and bottom of table

As far as I'm aware this isn't possible with HTML and CSS.

How do I Geocode 20 addresses without receiving an OVER_QUERY_LIMIT response?

I have just tested Google Geocoder and got the same problem as you have. I noticed I only get the OVER_QUERY_LIMIT status once every 12 requests So I wait for 1 second (that's the minimum delay to wait) It slows down the application but less than waiting 1 second every request

info = getInfos(getLatLng(code)); //In here I call Google API
record(code, info);
generated++; 
if(generated%interval == 0) {
holdOn(delay); // Every x requests, I sleep for 1 second
}

With the basic holdOn method :

private void holdOn(long delay) {
        try {
            Thread.sleep(delay);
        } catch (InterruptedException ex) {
            // ignore
        }
    }

Hope it helps

Kafka consumer list

High level consumers are registered into Zookeeper, so you can fetch a list from ZK, similarly to the way kafka-topics.sh fetches the list of topics. I don't think there's a way to collect all consumers; any application sending in a few consume requests is actually a "consumer", and you cannot tell whether they are done already.

On the consumer side, there's a JMX metric exposed to monitor the lag. Also, there is Burrow for lag monitoring.

Trim spaces from end of a NSString

I came up with this function, which basically behaves similarly to one in the answer by Alex:

-(NSString*)trimLastSpace:(NSString*)str{
    int i = str.length - 1;
    for (; i >= 0 && [str characterAtIndex:i] == ' '; i--);
    return [str substringToIndex:i + 1];
}

whitespaceCharacterSet besides space itself includes also tab character, which in my case could not appear. So i guess a plain comparison could suffice.

Is there a "between" function in C#?

And for negatives values:

    Public Function IsBetween(Of T)(item As T, pStart As T, pEnd As T) As Boolean ' https://msdn.microsoft.com/fr-fr/library/bb384936.aspx
    Dim Deb As T = pStart
    Dim Fin As T = pEnd
    If (Comparer(Of T).Default.Compare(pStart, pEnd) > 0) Then Deb = pEnd : Fin = pStart
    Return Comparer(Of T).Default.Compare(item, Deb) >= 0 AndAlso Comparer(Of T).Default.Compare(item, Fin) <= 0
End Function

Get element inside element by class and ID - JavaScript

Recursive function :

function getElementInsideElement(baseElement, wantedElementID) {
    var elementToReturn;
    for (var i = 0; i < baseElement.childNodes.length; i++) {
        elementToReturn = baseElement.childNodes[i];
        if (elementToReturn.id == wantedElementID) {
            return elementToReturn;
        } else {
            return getElementInsideElement(elementToReturn, wantedElementID);
        }
    }
}

openssl s_client -cert: Proving a client certificate was sent to the server

I know this is an old question but it does not yet appear to have an answer. I've duplicated this situation, but I'm writing the server app, so I've been able to establish what happens on the server side as well. The client sends the certificate when the server asks for it and if it has a reference to a real certificate in the s_client command line. My server application is set up to ask for a client certificate and to fail if one is not presented. Here is the command line I issue:

Yourhostname here -vvvvvvvvvv s_client -connect <hostname>:443 -cert client.pem -key cckey.pem -CAfile rootcert.pem -cipher ALL:!ADH:!LOW:!EXP:!MD5:@STRENGTH -tls1 -state

When I leave out the "-cert client.pem" part of the command the handshake fails on the server side and the s_client command fails with an error reported. I still get the report "No client certificate CA names sent" but I think that has been answered here above.

The short answer then is that the server determines whether a certificate will be sent by the client under normal operating conditions (s_client is not normal) and the failure is due to the server not recognizing the CA in the certificate presented. I'm not familiar with many situations in which two-way authentication is done although it is required for my project.

You are clearly sending a certificate. The server is clearly rejecting it.

The missing information here is the exact manner in which the certs were created and the way in which the provider loaded the cert, but that is probably all wrapped up by now.

How to get response as String using retrofit without using GSON or any other library in android

** Update ** A scalars converter has been added to retrofit that allows for a String response with less ceremony than my original answer below.

Example interface --

public interface GitHubService {
    @GET("/users/{user}")
    Call<String> listRepos(@Path("user") String user);
}

Add the ScalarsConverterFactory to your retrofit builder. Note: If using ScalarsConverterFactory and another factory, add the scalars factory first.

Retrofit retrofit = new Retrofit.Builder()
    .baseUrl(BASE_URL)
    .addConverterFactory(ScalarsConverterFactory.create())
    // add other factories here, if needed.
    .build();

You will also need to include the scalars converter in your gradle file --

implementation 'com.squareup.retrofit2:converter-scalars:2.1.0'

--- Original Answer (still works, just more code) ---

I agree with @CommonsWare that it seems a bit odd that you want to intercept the request to process the JSON yourself. Most of the time the POJO has all the data you need, so no need to mess around in JSONObject land. I suspect your specific problem might be better solved using a custom gson TypeAdapter or a retrofit Converter if you need to manipulate the JSON. However, retrofit provides more the just JSON parsing via Gson. It also manages a lot of the other tedious tasks involved in REST requests. Just because you don't want to use one of the features, doesn't mean you have to throw the whole thing out. There are times you just want to get the raw stream, so here is how to do it -

First, if you are using Retrofit 2, you should start using the Call API. Instead of sending an object to convert as the type parameter, use ResponseBody from okhttp --

public interface GitHubService {
    @GET("/users/{user}")
    Call<ResponseBody> listRepos(@Path("user") String user);
}

then you can create and execute your call --

GitHubService service = retrofit.create(GitHubService.class);
Call<ResponseBody> result = service.listRepos(username);
result.enqueue(new Callback<ResponseBody>() {
    @Override
    public void onResponse(Response<ResponseBody> response) {
        try {
            System.out.println(response.body().string());
        } catch (IOException e) {
            e.printStackTrace();
        }
    }

    @Override
    public void onFailure(Throwable t) {
        e.printStackTrace();
    }
});

Note The code above calls string() on the response object, which reads the entire response into a String. If you are passing the body off to something that can ingest streams, you can call charStream() instead. See the ResponseBody docs.

how to set auto increment column with sql developer

If you want to make your PK auto increment, you need to set the ID column property for that primary key.

  1. Right click on the table and select "Edit".
  2. In "Edit" Table window, select "columns", and then select your PK column.
  3. Go to ID Column tab and select Column Sequence as Type. This will create a trigger and a sequence, and associate the sequence to primary key.

See the picture below for better understanding.

enter image description here

// My source is: http://techatplay.wordpress.com/2013/11/22/oracle-sql-developer-create-auto-incrementing-primary-key/

INNER JOIN vs LEFT JOIN performance in SQL Server

Try both queries (the one with inner and left join) with OPTION (FORCE ORDER) at the end and post the results. OPTION (FORCE ORDER) is a query hint that forces the optimizer to build the execution plan with the join order you provided in the query.

If INNER JOIN starts performing as fast as LEFT JOIN, it's because:

  • In a query composed entirely by INNER JOINs, the join order doesn't matter. This gives freedom for the query optimizer to order the joins as it sees fit, so the problem might rely on the optimizer.
  • With LEFT JOIN, that's not the case because changing the join order will alter the results of the query. This means the engine must follow the join order you provided on the query, which might be better than the optimized one.

Don't know if this answers your question but I was once in a project that featured highly complex queries making calculations, which completely messed up the optimizer. We had cases where a FORCE ORDER would reduce the execution time of a query from 5 minutes to 10 seconds.

The mysql extension is deprecated and will be removed in the future: use mysqli or PDO instead

  1. Why is this happening?

    The entire ext/mysql PHP extension, which provides all functions named with the prefix mysql_, was officially deprecated in PHP v5.5.0 and removed in PHP v7.

    It was originally introduced in PHP v2.0 (November 1997) for MySQL v3.20, and no new features have been added since 2006. Coupled with the lack of new features are difficulties in maintaining such old code amidst complex security vulnerabilities.

    The manual has contained warnings against its use in new code since June 2011.

  2. How can I fix it?

    As the error message suggests, there are two other MySQL extensions that you can consider: MySQLi and PDO_MySQL, either of which can be used instead of ext/mysql. Both have been in PHP core since v5.0, so if you're using a version that is throwing these deprecation errors then you can almost certainly just start using them right away—i.e. without any installation effort.

    They differ slightly, but offer a number of advantages over the old extension including API support for transactions, stored procedures and prepared statements (thereby providing the best way to defeat SQL injection attacks). PHP developer Ulf Wendel has written a thorough comparison of the features.

    Hashphp.org has an excellent tutorial on migrating from ext/mysql to PDO.

  3. I understand that it's possible to suppress deprecation errors by setting error_reporting in php.ini to exclude E_DEPRECATED:

    error_reporting = E_ALL ^ E_DEPRECATED
    

    What will happen if I do that?

    Yes, it is possible to suppress such error messages and continue using the old ext/mysql extension for the time being. But you really shouldn't do this—this is a final warning from the developers that the extension may not be bundled with future versions of PHP (indeed, as already mentioned, it has been removed from PHP v7). Instead, you should take this opportunity to migrate your application now, before it's too late.

    Note also that this technique will suppress all E_DEPRECATED messages, not just those to do with the ext/mysql extension: therefore you may be unaware of other upcoming changes to PHP that would affect your application code. It is, of course, possible to only suppress errors that arise on the expression at issue by using PHP's error control operator—i.e. prepending the relevant line with @—however this will suppress all errors raised by that expression, not just E_DEPRECATED ones.


What should you do?

  • You are starting a new project.

    There is absolutely no reason to use ext/mysql—choose one of the other, more modern, extensions instead and reap the rewards of the benefits they offer.

  • You have (your own) legacy codebase that currently depends upon ext/mysql.

    It would be wise to perform regression testing: you really shouldn't be changing anything (especially upgrading PHP) until you have identified all of the potential areas of impact, planned around each of them and then thoroughly tested your solution in a staging environment.

    • Following good coding practice, your application was developed in a loosely integrated/modular fashion and the database access methods are all self-contained in one place that can easily be swapped out for one of the new extensions.

      Spend half an hour rewriting this module to use one of the other, more modern, extensions; test thoroughly. You can later introduce further refinements to reap the rewards of the benefits they offer.

    • The database access methods are scattered all over the place and cannot easily be swapped out for one of the new extensions.

      Consider whether you really need to upgrade to PHP v5.5 at this time.

      You should begin planning to replace ext/mysql with one of the other, more modern, extensions in order that you can reap the rewards of the benefits they offer; you might also use it as an opportunity to refactor your database access methods into a more modular structure.

      However, if you have an urgent need to upgrade PHP right away, you might consider suppressing deprecation errors for the time being: but first be sure to identify any other deprecation errors that are also being thrown.

  • You are using a third party project that depends upon ext/mysql.

    Consider whether you really need to upgrade to PHP v5.5 at this time.

    Check whether the developer has released any fixes, workarounds or guidance in relation to this specific issue; or, if not, pressure them to do so by bringing this matter to their attention. If you have an urgent need to upgrade PHP right away, you might consider suppressing deprecation errors for the time being: but first be sure to identify any other deprecation errors that are also being thrown.

    It is absolutely essential to perform regression testing.

Get input type="file" value when it has multiple files selected

The files selected are stored in an array: [input].files

For example, you can access the items

// assuming there is a file input with the ID `my-input`...
var files = document.getElementById("my-input").files;

for (var i = 0; i < files.length; i++)
{
 alert(files[i].name);
}

For jQuery-comfortable people, it's similarly easy

// assuming there is a file input with the ID `my-input`...
var files = $("#my-input")[0].files;

for (var i = 0; i < files.length; i++)
{
 alert(files[i].name);
}

How to change the integrated terminal in visual studio code or VSCode

From Official Docs

Correctly configuring your shell on Windows is a matter of locating the right executable and updating the setting. Below is a list of common shell executables and their default locations.

There is also the convenience command Select Default Shell that can be accessed through the command palette which can detect and set this for you.

So you can open a command palette using ctrl+shift+p, use the command Select Default Shell, then it displays all the available command line interfaces, select whatever you want, VS code sets that as default integrated terminal for you automatically.

If you want to set it manually find the location of executable of your cli and open user settings of vscode(ctrl+,) then set

"terminal.integrated.shell.windows":"path/to/executable.exe"

Example for gitbash on windows7:

"terminal.integrated.shell.windows":"C:\\Users\\stldev03\\AppData\\Local\\Programs\\Git\\bin\\bash.exe",

Errors in SQL Server while importing CSV file despite varchar(MAX) being used for each column

The Advanced Editor did not resolve my issue, instead I was forced to edit dtsx-file through notepad (or your favorite text/xml editor) and manually replace values in attributes to

length="0" dataType="nText" (I'm using unicode)

Always make a backup of the dtsx-file before you edit in text/xml mode.

Running SQL Server 2008 R2

Execute command without keeping it in history

You might consider using a shell without history, like perhaps

/bin/sh << END
   your commands without history
END

(perhaps /bin/dash or /bin/sash could be more appropriate than /bin/sh)

or even better use the batch utility e.g

batch << EOB
   your commands
EOB

The history would then contain sh or batch which is not very meaningful

How do I get rid of the "cannot empty the clipboard" error?

Try http://support.microsoft.com/kb/207438 which will work for 2007 if you follow v12.0 in the registry.

I/O error(socket error): [Errno 111] Connection refused

I previously had this problem with my EC2 instance (I was serving couchdb to serve resources -- am considering Amazon's S3 for the future).

One thing to check (assuming Ec2) is that the couchdb port is added to your open ports within your security policy.

I specifically encountered

"[Errno 111] Connection refused"

over EC2 when the instance was stopped and started. The problem seems to be a pidfile race. The solution for me was killing couchdb (entirely and properly) via:

pkill -f couchdb

and then restarting with:

/etc/init.d/couchdb restart

Can I pass a JavaScript variable to another browser window?

For me the following doesn't work

var A = {foo:'bar'};
var w = window.open("http://example.com");
w.B = A;

// in new window
var B = window.opener.B;

But this works(note the variable name)

var B = {foo:'bar'};
var w = window.open("http://example.com");
w.B = B;

// in new window
var B = window.opener.B;

Also var B should be global.

How can I read pdf in python?

You can use textract module in python

Textract

for install

pip install textract

for read pdf

import textract
text = textract.process('path/to/pdf/file', method='pdfminer')

For detail Textract

How to add an object to an ArrayList in Java

Contacts.add(objt.Data(name, address, contact));

This is not a perfect way to call a constructor. The constructor is called at the time of object creation automatically. If there is no constructor java class creates its own constructor.

The correct way is:

// object creation. 
Data object1 = new Data(name, address, contact);      

// adding Data object to ArrayList object Contacts.
Contacts.add(object1);                              

Access restriction: Is not accessible due to restriction on required library ..\jre\lib\rt.jar

In the eclipse environment where you execute your java programs, take the following steps:

  1. Click on Project just above the menu bar in eclipse.
  2. Click on properties.
  3. Select libraries, click on the existing library and click Remove on the right of the window.
  4. Repeat the process and now click add library, then select JRE system library and click OK.

UnicodeDecodeError: 'utf8' codec can't decode byte 0xa5 in position 0: invalid start byte

The following snippet worked for me.

import pandas as pd
df = pd.read_csv(filename, sep = ';', encoding = 'latin1', error_bad_lines=False) #error_bad_lines is avoid single line error

How to finish current activity in Android

You need to call finish() from the UI thread, not a background thread. The way to do this is to declare a Handler and ask the Handler to run a Runnable on the UI thread. For example:

public class LoadingScreen extends Activity{
    private LoadingScreen loadingScreen;
    Intent i = new Intent(this, HomeScreen.class);
    Handler handler;
    @Override
    public void onCreate(Bundle savedInstanceState) {
        super.onCreate(savedInstanceState);
        handler = new Handler();
        setContentView(R.layout.loading);

        CountDownTimer timer = new CountDownTimer(10000, 1000) //10seceonds Timer
        {
             @Override
             public void onTick(long l) 
             {

             }

             @Override
             public void onFinish() 
             {
                 handler.post(new Runnable() {
                     public void run() {
                         loadingScreen.finishActivity(0);
                         startActivity(i);
                     }
                 });
             };
        }.start();
    }
}

ERROR Error: Uncaught (in promise), Cannot match any routes. URL Segment

As the error says your router link should match the existing routes configured

It should be just routerLink="/about"

Convert timestamp to readable date/time PHP

If you are using PHP date(), you can use this code to get the date, time, second, etc.

$time = time();               // you have 1299446702 in time
$year = $time/31556926 % 12;  // to get year
$week = $time / 604800 % 52;  // to get weeks
$hour = $time / 3600 % 24;    // to get hours
$minute = $time / 60 % 60;    // to get minutes
$second = $time % 60;         // to get seconds

Console.log(); How to & Debugging javascript

console.log() just takes whatever you pass to it and writes it to a console's log window. If you pass in an array, you'll be able to inspect the array's contents. Pass in an object, you can examine the object's attributes/methods. pass in a string, it'll log the string. Basically it's "document.write" but can intelligently take apart its arguments and write them out elsewhere.

It's useful to outputting occasional debugging information, but not particularly useful if you have a massive amount of debugging output.

To watch as a script's executing, you'd use a debugger instead, which allows you step through the code line-by-line. console.log's used when you need to display what some variable's contents were for later inspection, but do not want to interrupt execution.

HTTP POST and GET using cURL in Linux

*nix provides a nice little command which makes our lives a lot easier.

GET:

with JSON:

curl -i -H "Accept: application/json" -H "Content-Type: application/json" -X GET http://hostname/resource

with XML:

curl -H "Accept: application/xml" -H "Content-Type: application/xml" -X GET http://hostname/resource

POST:

For posting data:

curl --data "param1=value1&param2=value2" http://hostname/resource

For file upload:

curl --form "[email protected]" http://hostname/resource

RESTful HTTP Post:

curl -X POST -d @filename http://hostname/resource

For logging into a site (auth):

curl -d "username=admin&password=admin&submit=Login" --dump-header headers http://localhost/Login
curl -L -b headers http://localhost/

Pretty-printing the curl results:

For JSON:

If you use npm and nodejs, you can install json package by running this command:

npm install -g json

Usage:

curl -i -H "Accept: application/json" -H "Content-Type: application/json" -X GET http://hostname/resource | json

If you use pip and python, you can install pjson package by running this command:

pip install pjson

Usage:

curl -i -H "Accept: application/json" -H "Content-Type: application/json" -X GET http://hostname/resource | pjson

If you use Python 2.6+, json tool is bundled within.

Usage:

curl -i -H "Accept: application/json" -H "Content-Type: application/json" -X GET http://hostname/resource | python -m json.tool

If you use gem and ruby, you can install colorful_json package by running this command:

gem install colorful_json

Usage:

curl -i -H "Accept: application/json" -H "Content-Type: application/json" -X GET http://hostname/resource | cjson

If you use apt-get (aptitude package manager of your Linux distro), you can install yajl-tools package by running this command:

sudo apt-get install yajl-tools

Usage:

curl -i -H "Accept: application/json" -H "Content-Type: application/json" -X GET http://hostname/resource |  json_reformat

For XML:

If you use *nix with Debian/Gnome envrionment, install libxml2-utils:

sudo apt-get install libxml2-utils

Usage:

curl -H "Accept: application/xml" -H "Content-Type: application/xml" -X GET http://hostname/resource | xmllint --format -

or install tidy:

sudo apt-get install tidy

Usage:

curl -H "Accept: application/xml" -H "Content-Type: application/xml" -X GET http://hostname/resource | tidy -xml -i -

Saving the curl response to a file

curl http://hostname/resource >> /path/to/your/file

or

curl http://hostname/resource -o /path/to/your/file

For detailed description of the curl command, hit:

man curl

For details about options/switches of the curl command, hit:

curl -h

How to center buttons in Twitter Bootstrap 3?

According to the Twitter Bootstrap documentation: http://getbootstrap.com/css/#helper-classes-center

<!-- Button -->
<div class="form-group">
   <label class="col-md-4 control-label" for="singlebutton"></label>
   <div class="col-md-4 center-block">
      <button id="singlebutton" name="singlebutton" class="btn btn-primary center-block">
          Next Step!
       </button>
   </div>  
</div>

All the class center-block does is to tell the element to have a margin of 0 auto, the auto being the left/right margins. However, unless the class text-center or css text-align:center; is set on the parent, the element does not know the point to work out this auto calculation from so will not center itself as anticipated.

See an example of the code above here: https://jsfiddle.net/Seany84/2j9pxt1z/

Why is my Git Submodule HEAD detached from master?

Check out my answer here: Git submodules: Specify a branch/tag

If you want, you can add the "branch = master" line into your .gitmodules file manually. Read the link to see what I mean.

EDIT: To track an existing submodule project at a branch, follow VonC's instructions here instead:

Git submodules: Specify a branch/tag

Using column alias in WHERE clause of MySQL query produces an error

I am using mysql 5.5.24 and the following code works:

select * from (
SELECT `users`.`first_name`, `users`.`last_name`, `users`.`email`,
SUBSTRING(`locations`.`raw`,-6,4) AS `guaranteed_postcode`
FROM `users` LEFT OUTER JOIN `locations`
ON `users`.`id` = `locations`.`user_id`
) as a
WHERE guaranteed_postcode NOT IN --this is where the fake col is being used
(
 SELECT `postcode` FROM `postcodes` WHERE `region` IN
 (
  'australia'
 )
)

Rolling back local and remote git repository by 1 commit

There are many way you can do this. Based on your requirement choose anything from below.

1. By REVERTing commit:

If you want to REVERT all the changes from you last COMMIT that means If you ADD something in your file that will be REMOVED after revert has been done. If you REMOVE something in your file the revert process will ADD those file.

You can REVERT the very last COMMIT. Like:

1.git revert head^
2.git push origin <Branch-Name>

Or you can revert to any previous commit using the hash of that commit.Like:

1.git revert <SHA>
2.git push origin  <Branch-Name>

2. By RESETing previous Head

If you want to just point to any previous commit use reset; it points your local environment back to a previous commit. You can reset your head to previous commit or reset your head to previous any commit.

Reset to previous commit.

1.git reset head^
2.git push -f origin <Branch-name>

Reset to any previous commit:

1.git reset <SHA>
2.git push -f origin <Branch-name>

Trade of between REVERT & RESET:

Why would you choose to do a revert over a reset operation? If you have already pushed your chain of commits to the remote repository (where others may have pulled your code and started working with it), a revert is a nicer way to cancel out changes for them. This is because the Git workflow works well for picking up additional commits at the end of a branch, but it can be challenging if a set of commits is no longer seen in the chain when someone resets the branch pointer back.

How to create a BKS (BouncyCastle) format Java Keystore that contains a client certificate chain

Not sure you resolved this issue or not, but this is how I do it and it works on Android:

  1. Use openssl to merge client's cert(cert must be signed by a CA that accepted by server) and private key into a PCKS12 format key pair: openssl pkcs12 -export -in clientcert.pem -inkey clientkey.pem -out client.p12
  2. You may need patch your JRE to umlimited strength encryption depends on your key strength: copy the jar files fromJCE 5.0 unlimited strength Jurisdiction Policy FIles and override those in your JRE (eg.C:\Program Files\Java\jre6\lib\security)
  3. Use Portecle tool mentioned above and create a new keystore with BKS format
  4. Import PCKS12 key pair generated in step 1 and save it as BKS keystore. This keystore works with Android client authentication.
  5. If you need to do certificate chain, you can use this IBM tool:KeyMan to merge client's PCKS12 key pair with CA cert. But it only generate JKS keystore, so you again need Protecle to convert it to BKS format.

How do I pretty-print existing JSON data with Java?

I think for pretty-printing something, it's very helpful to know its structure.

To get the structure you have to parse it. Because of this, I don't think it gets much easier than first parsing the JSON string you have and then using the pretty-printing method toString mentioned in the comments above.

Of course you can do similar with any JSON library you like.

What is the best free SQL GUI for Linux for various DBMS systems

For Oracle, I highly recommend the free Oracle SQL Developer

http://www.oracle.com/technology/products/database/sql_developer/index.html

The doucmentation states it also works with non-oracle databases - i've never tried that feature myself, but I do know that it works really well with Oracle

How can I check if given int exists in array?

You can use std::find for this:

#include <algorithm> // for std::find
#include <iterator> // for std::begin, std::end

int main () 
{
  int a[] = {3, 6, 8, 33};
  int x = 8;
  bool exists = std::find(std::begin(a), std::end(a), x) != std::end(a);
}

std::find returns an iterator to the first occurrence of x, or an iterator to one-past the end of the range if x is not found.

Pointer to 2D arrays in C

int *pointer[280]; //Creates 280 pointers of type int.

In 32 bit os, 4 bytes for each pointer. so 4 * 280 = 1120 bytes.

int (*pointer)[100][280]; // Creates only one pointer which is used to point an array of [100][280] ints.

Here only 4 bytes.

Coming to your question, int (*pointer)[280]; and int (*pointer)[100][280]; are different though it points to same 2D array of [100][280].

Because if int (*pointer)[280]; is incremented, then it will points to next 1D array, but where as int (*pointer)[100][280]; crosses the whole 2D array and points to next byte. Accessing that byte may cause problem if that memory doen't belongs to your process.

What possibilities can cause "Service Unavailable 503" error?

Your web pages are served by an application pool. If you disable/stop the application pool, and anyone tries to browse the application, you will get a Service Unavailable. It can happen due to multiple reasons...

  1. Your application may have crashed [check the event viewer and see if you can find event logs in your Application/System log]

  2. Your application may be crashing very frequently. If an app pool crashes for 5 times in 5 minutes [check your application pool settings for rapid fail], your application pool is disabled by IIS and you will end up getting this message.

In either case, the issue is that your worker process is failing and you should troubleshoot it from crash perspective.

What is a Crash (technically)... in ASP.NET and what to do if it happens?

Powershell command to hide user from exchange address lists

You will have to pass one of the valid Identity values like DN, domain\user etc to the Set-Mailbox cmdlet. Currently you are not passing anything.

How to throw a C++ exception

Just add throw where needed, and try block to the caller that handles the error. By convention you should only throw things that derive from std::exception, so include <stdexcept> first.

int compare(int a, int b) {
    if (a < 0 || b < 0) {
        throw std::invalid_argument("a or b negative");
    }
}

void foo() {
    try {
        compare(-1, 0);
    } catch (const std::invalid_argument& e) {
        // ...
    }
}

Also, look into Boost.Exception.

Bootstrap throws Uncaught Error: Bootstrap's JavaScript requires jQuery

If this occurs IE intranet only, check compatibility settings and uncheck "Display intranet sites in Compatibility mode" .

IE-->settings-->compatibility

enter image description here

Count how many rows have the same value

Try

SELECT NAME, count(*) as NUM FROM tbl GROUP BY NAME

SQL FIDDLE

Installing a plain plugin jar in Eclipse 3.5

This is how you can go about it:

  1. Close Eclipse
  2. Download a jar plugin (let's assume its testNG.jar)
  3. Copy testNG.jar to a certain folder (say C:\Project\resources\plugins)
  4. In your Eclipse installation folder, there is a folder named dropins (could be C:\eclipse\dropins), create a .link file in that folder, (like plugins.link)
  5. Open this file with any text editor and enter this one line:
    path=C:/Project/resources/plugins
  6. Save the file and start Eclipse.

And you are good to go!

Please do not forget to change your backward slashes in your plugins folder path to forward slashes on step 5. I used to forget and it would take my time unnecessarily.

Set a path variable with spaces in the path in a Windows .cmd file or batch file

also just try adding double slashes like this works for me only

set dir="C:\\1. Some Folder\\Some Other Folder\\Just Because"

@echo on MKDIR %dir%

OMG after posting they removed the second \ in my post so if you open my comment and it shows three you should read them as two......

nodejs send html file to client

Try your code like this:

var app = express();
app.get('/test', function(req, res) {
    res.sendFile('views/test.html', {root: __dirname })
});
  1. Use res.sendFile instead of reading the file manually so express can handle setting the content-type properly for you.

  2. You don't need the app.engine line, as that is handled internally by express.

What is the garbage collector in Java?

The basic principles of garbage collection are to find data objects in a program that cannot be accessed in the future, and to reclaim the resources used by those objects. https://en.wikipedia.org/wiki/Garbage_collection_%28computer_science%29

Advantages

1) Saves from bugs, which occur when a piece of memory is freed while there are still pointers to it, and one of those pointers is dereferenced. https://en.wikipedia.org/wiki/Dangling_pointer

2) Double free bugs, which occur when the program tries to free a region of memory that has already been freed, and perhaps already been allocated again.

3) Prevents from certain kinds of memory leaks, in which a program fails to free memory occupied by objects that have become unreachable, which can lead to memory exhaustion.

Disadvantages

1) Consuming additional resources, performance impacts, possible stalls in program execution, and incompatibility with manual resource management. Garbage collection consumes computing resources in deciding which memory to free, even though the programmer may have already known this information.

2) The moment when the garbage is actually collected can be unpredictable, resulting in stalls (pauses to shift/free memory) scattered throughout a session. Unpredictable stalls can be unacceptable in real-time environments, in transaction processing, or in interactive programs.


Oracle tutorial http://www.oracle.com/webfolder/technetwork/tutorials/obe/java/gc01/index.html

Garbage collection is the process identifying which objects are in use and which are not, and deleting the unused objects.

In a programming languages like C, C++, allocating and freeing memory is a manual process.

int * array = new int[size];
processArray(array); //do some work.
delete array; //Free memory

The first step in the process is called marking. This is where the garbage collector identifies which pieces of memory are in use and which are not.

Step 2a. Normal deletion removes unreferenced objects leaving referenced objects and pointers to free space.

To improve performance, we want to delete unreferenced objects and also compact the remaining referenced objects. We want to keep referenced objects together, so it will be faster to allocate new memory.

As stated earlier, having to mark and compact all the objects in a JVM is inefficient. As more and more objects are allocated, the list of objects grows and grows leading to longer and longer garbage collection time.

Continue reading this tutorial, and you will know how GC takes this challenge.

In short, there are three regions of the heap, YoungGeneration for short life objects, OldGeneration for long period objects, and PermanentGeneration for objects that live during the application life, for example, classes, libraries.

CSS strikethrough different color from text?

Here you go:

_x000D_
_x000D_
<style>body {color: #000;}</style>_x000D_
<del>&nbsp;&nbsp;<span style="color:#999">facebook</span>&nbsp;&nbsp;</del>
_x000D_
_x000D_
_x000D_

How to Publish Web with msbuild?

For generating the publish output provide one more parameter. msbuild example.sln /p:publishprofile=profilename /p:deployonbuild=true /p:configuration=debug/or any

Count unique values with pandas per groups

IIUC you want the number of different ID for every domain, then you can try this:

output = df.drop_duplicates()
output.groupby('domain').size()

output:

    domain
facebook.com    1
google.com      1
twitter.com     2
vk.com          3
dtype: int64

You could also use value_counts, which is slightly less efficient.But the best is Jezrael's answer using nunique:

%timeit df.drop_duplicates().groupby('domain').size()
1000 loops, best of 3: 939 µs per loop
%timeit df.drop_duplicates().domain.value_counts()
1000 loops, best of 3: 1.1 ms per loop
%timeit df.groupby('domain')['ID'].nunique()
1000 loops, best of 3: 440 µs per loop

Make a DIV fill an entire table cell

I propose a solution using the experimental Flexbox to simulate a table layout which will allow a cell's content element to fill up its parent cell vertically:

Demo

_x000D_
_x000D_
.table{ display:flex; border:2px solid red; }_x000D_
.table > *{ flex: 1; border:2px solid blue; position:relative; }_x000D_
.fill{ background:lightgreen; height:100%; position:absolute; left:0; right:0; }_x000D_
_x000D_
/* Reset */_x000D_
*{ padding:0; margin:0; }_x000D_
body{ padding:10px; }
_x000D_
<div class='table'>_x000D_
  <aside><div class='fill'>Green should be 100% height</div></aside>_x000D_
  <aside></aside>_x000D_
  <aside>_x000D_
    <p>Lorem ipsum dolor sit amet, consectetur adipiscing elit. Phasellus imperdiet, nulla et dictum interdum, nisi lorem egestas odio, vitae scelerisque enim ligula venenatis dolor. Maecenas nisl est, ultrices nec congue eget, auctor vitae massa. Fusce luctus vestibulum augue ut aliquet. Mauris ante ligula, facilisis sed ornare eu, lobortis in odio. Praesent convallis urna a lacus interdum ut hendrerit risus congue. Nunc sagittis dictum nisi, sed ullamcorper ipsum dignissim ac. In at libero sed nunc venenatis imperdiet sed ornare turpis. Donec vitae dui eget tellus gravida venenatis. Integer fringilla congue eros non fermentum. Sed dapibus pulvinar nibh tempor porta. Cras ac leo purus. Mauris quis diam velit. Lorem ipsum dolor sit amet, consectetur adipiscing elit. Phasellus imperdiet, nulla et dictum interdum, nisi lorem egestas odio, vitae scelerisque enim ligula venenatis dolor. Maecenas nisl est, ultrices nec congue eget, auctor vitae massa. Fusce luctus vestibulum augue ut aliquet. Mauris ante ligula, facilisis sed ornare eu, lobortis in odio. Praesent convallis urna a lacus interdum ut hendrerit risus conguet.</p>_x000D_
  </aside>_x000D_
</div>
_x000D_
_x000D_
_x000D_

Can't compile C program on a Mac after upgrade to Mojave

I was having this issue and nothing worked. I ran xcode-select --install and also installed /Library/Developer/CommandLineTools/Packages/macOS_SDK_headers_for_macOS_10.14.pkg.

BACKGROUND

Since I was having issues with App Store on a new laptop, I was forced to download the Xcode Beta installer from the Apple website to install Xcode outside App Store. So I only had Xcode Beta installed.

SOLUTION

This, (I think), was making clang to not find the SDKROOT directory /Applications/Xcode.app/...., because there is no Beta in the path, or maybe Xcode Beta simply doesn't install it (I don't know). To fix the issue, I had to remove Xcode Beta and resolve the App Store issue to install the release version.

tldr;

If you have Xcode Beta, try cleaning up everything and installing the release version before trying out the solutions that are working for other people.

How to append elements into a dictionary in Swift?

I added Dictionary extension

extension Dictionary {   
  func cloneWith(_ dict: [Key: Value]) -> [Key: Value] {
    var result = self
    dict.forEach { key, value in result[key] = value }
    return result  
  }
}

you can use cloneWith like this

 newDictionary = dict.reduce([3 : "efg"]) { r, e in r.cloneWith(e) }

PostgreSQL: Resetting password of PostgreSQL on Ubuntu

Assuming you're the administrator of the machine, Ubuntu has granted you the right to sudo to run any command as any user.
Also assuming you did not restrict the rights in the pg_hba.conf file (in the /etc/postgresql/9.1/main directory), it should contain this line as the first rule:

# Database administrative login by Unix domain socket  
local   all             postgres                                peer

(About the file location: 9.1 is the major postgres version and main the name of your "cluster". It will differ if using a newer version of postgres or non-default names. Use the pg_lsclusters command to obtain this information for your version/system).

Anyway, if the pg_hba.conf file does not have that line, edit the file, add it, and reload the service with sudo service postgresql reload.

Then you should be able to log in with psql as the postgres superuser with this shell command:

sudo -u postgres psql

Once inside psql, issue the SQL command:

ALTER USER postgres PASSWORD 'newpassword';

In this command, postgres is the name of a superuser. If the user whose password is forgotten was ritesh, the command would be:

ALTER USER ritesh PASSWORD 'newpassword';

References: PostgreSQL 9.1.13 Documentation, Chapter 19. Client Authentication

Keep in mind that you need to type postgres with a single S at the end

If leaving the password in clear text in the history of commands or the server log is a problem, psql provides an interactive meta-command to avoid that, as an alternative to ALTER USER ... PASSWORD:

\password username

It asks for the password with a double blind input, then hashes it according to the password_encryption setting and issue the ALTER USER command to the server with the hashed version of the password, instead of the clear text version.

ReferenceError: variable is not defined

Got the error (in the function init) with the following code ;

"use strict" ;

var hdr ;

function init(){ // called on load
    hdr = document.getElementById("hdr");
}

... while using the stock browser on a Samsung galaxy Fame ( crap phone which makes it a good tester ) - userAgent ; Mozilla/5.0 (Linux; U; Android 4.1.2; en-gb; GT-S6810P Build/JZO54K) AppleWebKit/534.30 (KHTML, like Gecko) Version/4.0 Mobile Safari/534.30

The same code works everywhere else I tried including the stock browser on an older HTC phone - userAgent ; Mozilla/5.0 (Linux; U; Android 2.3.5; en-gb; HTC_WildfireS_A510e Build/GRJ90) AppleWebKit/533.1 (KHTML, like Gecko) Version/4.0 Mobile Safari/533.1

The fix for this was to change

var hdr ;

to

var hdr = null ;

How do you create a daemon in Python?

I am afraid the daemon module mentioned by @Dustin didn't work for me. Instead I installed python-daemon and used the following code:

# filename myDaemon.py
import sys
import daemon
sys.path.append('/home/ubuntu/samplemodule') # till __init__.py
from samplemodule import moduleclass 

with daemon.DaemonContext():
    moduleclass.do_running() # I have do_running() function and whatever I was doing in __main__() in module.py I copied in it.

Running is easy

> python myDaemon.py

just for completeness here is samplemodule directory content

>ls samplemodule
__init__.py __init__.pyc moduleclass.py

The content of moduleclass.py can be

class moduleclass():
    ...

def do_running():
    m = moduleclass()
    # do whatever daemon is required to do.

How to file split at a line number

file_name=test.log

# set first K lines:
K=1000

# line count (N): 
N=$(wc -l < $file_name)

# length of the bottom file:
L=$(( $N - $K ))

# create the top of file: 
head -n $K $file_name > top_$file_name

# create bottom of file: 
tail -n $L $file_name > bottom_$file_name

Also, on second thought, split will work in your case, since the first split is larger than the second. Split puts the balance of the input into the last split, so

split -l 300000 file_name

will output xaa with 300k lines and xab with 100k lines, for an input with 400k lines.

Bootstrap Dropdown menu is not working

In my case, disabling Chrome Extensions fixed it. I removed them from Chrome one by one until I found the culprit.

Since I'm the author of the offending Chrome extension, I guess I better fix the extension!

Jenkins Git Plugin: How to build specific tag?

In a latest Jenkins (1.639 and above) you can:

  1. just specify name of tag in a field 'Branches to build'.
  2. in a parametrized build you can use parameter as variable in a same field 'Branches to build' i.e. ${Branch_to_build}.
  3. you can install Git Parameter Plugin which will provide to you functionality by listing of all available branches and tags.

Directory Chooser in HTML page

Can't be done in pure HTML/JavaScript for security reasons.

Selecting a file for upload is the best you can do, and even then you won't get its full original path in modern browsers.

You may be able to put something together using Java or Flash (e.g. using SWFUpload as a basis), but it's a lot of work and brings additional compatibility issues.

Another thought would be opening an iframe showing the user's C: drive (or whatever) but even if that's possible nowadays (could be blocked for security reasons, haven't tried in a long time) it will be impossible for your web site to communicate with the iframe (again for security reasons).

What do you need this for?

undefined reference to WinMain@16 (codeblocks)

I had the same error problem using Code Blocks rev 13.12. I may be wrong here since I am less than a beginner :)

My problem was that I accidentally capitalized "M" in Main() instead of ALL lowercase = main() - once corrected, it worked!!!

I noticed that you have "int main()" instead of "main()". Is this the problem, or is it supposed to be that way?

Hope I could help...

How to check if a string contains a substring in Bash

As Paul mentioned in his performance comparison:

if echo "abcdefg" | grep -q "bcdef"; then
    echo "String contains is true."
else
    echo "String contains is not true."
fi

This is POSIX compliant like the 'case "$string" in' the answer provided by Marcus, but it is slightly easier to read than the case statement answer. Also note that this will be much much slower than using a case statement. As Paul pointed out, don't use it in a loop.

How To Define a JPA Repository Query with a Join

You are experiencing this issue for two reasons.

  • The JPQL Query is not valid.
  • You have not created an association between your entities that the underlying JPQL query can utilize.

When performing a join in JPQL you must ensure that an underlying association between the entities attempting to be joined exists. In your example, you are missing an association between the User and Area entities. In order to create this association we must add an Area field within the User class and establish the appropriate JPA Mapping. I have attached the source for User below. (Please note I moved the mappings to the fields)

User.java

@Entity
@Table(name="user")
public class User {

    @Id
    @GeneratedValue(strategy=GenerationType.AUTO)
    @Column(name="iduser")
    private Long idUser;

    @Column(name="user_name")
    private String userName;

    @OneToOne()
    @JoinColumn(name="idarea")
    private Area area;

    public Long getIdUser() {
        return idUser;
    }

    public void setIdUser(Long idUser) {
        this.idUser = idUser;
    }

    public String getUserName() {
        return userName;
    }

    public void setUserName(String userName) {
        this.userName = userName;
    }

    public Area getArea() {
        return area;
    }

    public void setArea(Area area) {
        this.area = area;
    }
}

Once this relationship is established you can reference the area object in your @Query declaration. The query specified in your @Query annotation must follow proper syntax, which means you should omit the on clause. See the following:

@Query("select u.userName from User u inner join u.area ar where ar.idArea = :idArea")

While looking over your question I also made the relationship between the User and Area entities bidirectional. Here is the source for the Area entity to establish the bidirectional relationship.

Area.java

@Entity
@Table(name = "area")
public class Area {

    @Id
    @GeneratedValue(strategy=GenerationType.AUTO)
    @Column(name="idarea")
    private Long idArea;

    @Column(name="area_name")
    private String areaName;

    @OneToOne(fetch=FetchType.LAZY, mappedBy="area")
    private User user;

    public Long getIdArea() {
        return idArea;
    }

    public void setIdArea(Long idArea) {
        this.idArea = idArea;
    }

    public String getAreaName() {
        return areaName;
    }

    public void setAreaName(String areaName) {
        this.areaName = areaName;
    }

    public User getUser() {
        return user;
    }

    public void setUser(User user) {
        this.user = user;
    }
}

How to parse the Manifest.mbdb file in an iOS 4.0 iTunes Backup

I liked galloglas's code, and I changed the main function so that it shows a sorted list of total size by application:

verbose = True
if __name__ == '__main__':
    mbdb = process_mbdb_file("Manifest.mbdb")
    mbdx = process_mbdx_file("Manifest.mbdx")
    sizes = {}
    for offset, fileinfo in mbdb.items():
        if offset in mbdx:
            fileinfo['fileID'] = mbdx[offset]
        else:
            fileinfo['fileID'] = "<nofileID>"
            print >> sys.stderr, "No fileID found for %s" % fileinfo_str(fileinfo)
        print fileinfo_str(fileinfo, verbose)
        if (fileinfo['mode'] & 0xE000) == 0x8000:
        sizes[fileinfo['domain']]= sizes.get(fileinfo['domain'],0) + fileinfo['filelen']
    for domain in sorted(sizes, key=sizes.get):
        print "%-60s %11d (%dMB)" % (domain, sizes[domain], int(sizes[domain]/1024/1024))

That way you can figure out what application is eating all that space.

How to subtract/add days from/to a date?

The answer probably depends on what format your date is in, but here is an example using the Date class:

dt <- as.Date("2010/02/10")
new.dt <- dt - as.difftime(2, unit="days")

You can even play with different units like weeks.

HttpContext.Current.Session is null when routing requests

It seems that you have forgotten to add your state server address in the config file.

 <sessionstate mode="StateServer" timeout="20" server="127.0.0.1" port="42424" />

How to find the minimum value in an ArrayList, along with the index number? (Java)

public static int minIndex (ArrayList<Float> list) {
  return list.indexOf (Collections.min(list));
 }
System.out.println("Min = " + list.get(minIndex(list));

Listing information about all database files in SQL Server

I've created this query:

SELECT 
    db.name AS                                   [Database Name], 
    mf.name AS                                   [Logical Name], 
    mf.type_desc AS                              [File Type], 
    mf.physical_name AS                          [Path], 
    CAST(
        (mf.Size * 8
        ) / 1024.0 AS DECIMAL(18, 1)) AS         [Initial Size (MB)], 
    'By '+IIF(
            mf.is_percent_growth = 1, CAST(mf.growth AS VARCHAR(10))+'%', CONVERT(VARCHAR(30), CAST(
        (mf.growth * 8
        ) / 1024.0 AS DECIMAL(18, 1)))+' MB') AS [Autogrowth], 
    IIF(mf.max_size = 0, 'No growth is allowed', IIF(mf.max_size = -1, 'Unlimited', CAST(
        (
                CAST(mf.max_size AS BIGINT) * 8
        ) / 1024 AS VARCHAR(30))+' MB')) AS      [MaximumSize]
FROM 
     sys.master_files AS mf
     INNER JOIN sys.databases AS db ON
            db.database_id = mf.database_id

How to submit a form with JavaScript by clicking a link?

HTML & CSS - No Javascript Solution

Make your button appear like a Bootstrap link

HTML:

<form>
    <button class="btn-link">Submit</button>
</form>

CSS:

.btn-link {

    background: none;
    border: none;
    padding: 0px;
    color: #3097D1;
    font: inherit;

}

.btn-link:hover {

    color: #216a94;
    text-decoration: underline;

}

WinForms DataGridView font size

1st Step: Go to the form where datagridview is added

2nd step: click on the datagridview at the top right side there will be displayed a small button of like play icon or arrow to edit the datagridview.

3rd step: click on that button and select edit columns now click the attributes you want to increase font size.

4th step: on the right side of the property menu the first on the list column named defaultcellstyle click on its property a new window will open to change the font and font size.

How to add "on delete cascade" constraints?

Usage:

select replace_foreign_key('user_rates_posts', 'post_id', 'ON DELETE CASCADE');

Function:

CREATE OR REPLACE FUNCTION 
    replace_foreign_key(f_table VARCHAR, f_column VARCHAR, new_options VARCHAR) 
RETURNS VARCHAR
AS $$
DECLARE constraint_name varchar;
DECLARE reftable varchar;
DECLARE refcolumn varchar;
BEGIN

SELECT tc.constraint_name, ccu.table_name AS foreign_table_name, ccu.column_name AS foreign_column_name 
FROM 
    information_schema.table_constraints AS tc 
    JOIN information_schema.key_column_usage AS kcu
      ON tc.constraint_name = kcu.constraint_name
    JOIN information_schema.constraint_column_usage AS ccu
      ON ccu.constraint_name = tc.constraint_name
WHERE constraint_type = 'FOREIGN KEY' 
   AND tc.table_name= f_table AND kcu.column_name= f_column
INTO constraint_name, reftable, refcolumn;

EXECUTE 'alter table ' || f_table || ' drop constraint ' || constraint_name || 
', ADD CONSTRAINT ' || constraint_name || ' FOREIGN KEY (' || f_column || ') ' ||
' REFERENCES ' || reftable || '(' || refcolumn || ') ' || new_options || ';';

RETURN 'Constraint replaced: ' || constraint_name || ' (' || f_table || '.' || f_column ||
 ' -> ' || reftable || '.' || refcolumn || '); New options: ' || new_options;

END;
$$ LANGUAGE plpgsql;

Be aware: this function won't copy attributes of initial foreign key. It only takes foreign table name / column name, drops current key and replaces with new one.

Gradle project refresh failed after Android Studio update

File -> Invalidate Caches / Restart -> Invalidate and Restart worked for me.

The intel x86 emulator accelerator (HAXM installer) revision 6.0.5 is showing not compatible with windows

Did you read https://software.intel.com/en-us/blogs/2014/03/14/troubleshooting-intel-haxm?

It says "Make sure "Hyper-V", a Windows feature, is not installed/enabled on your system. Hyper-V captures the VT virtualization capability of the CPU, and HAXM and Hyper-V cannot run at the same time. Read this blog: Creating a "no hypervisor" boot entry." https://blogs.msdn.microsoft.com/virtual_pc_guy/2008/04/14/creating-a-no-hypervisor-boot-entry/

I've created the boot entry that disables HyperV and it's working

Make DateTimePicker work as TimePicker only in WinForms

A snippet out of the MSDN:

'The following code sample shows how to create a DateTimePicker that enables users to choose a time only.'

timePicker = new DateTimePicker();
timePicker.Format = DateTimePickerFormat.Time;
timePicker.ShowUpDown = true;

Create a symbolic link of directory in Ubuntu

That's what ln is documented to do when the target already exists and is a directory. If you want /etc/nginx to be a symlink rather than contain a symlink, you had better not create it as a directory first!

How can I render repeating React elements?

To expand on Ross Allen's answer, here is a slightly cleaner variant using ES6 arrow syntax.

{this.props.titles.map(title =>
  <th key={title}>{title}</th>
)}

It has the advantage that the JSX part is isolated (no return or ;), making it easier to put a loop around it.

Run php function on button click

You can use isset().

<form method="post">
    <input type="submit" name="test" id="test" value="RUN" />

</form>

<?php

function testfun()
{
   echo "Your test function on button click is working";
}

if(isset($_POST('submit')))
{
   testfun();
}

?>

Find and replace in file and overwrite file doesn't work, it empties the file

use sed's -i option, e.g.

sed -i bak -e s/STRING_TO_REPLACE/REPLACE_WITH/g index.html

Private vs Protected - Visibility Good-Practice Concern

I read an article a while ago that talked about locking down every class as much as possible. Make everything final and private unless you have an immediate need to expose some data or functionality to the outside world. It's always easy to expand the scope to be more permissible later on, but not the other way around. First consider making as many things as possible final which will make choosing between private and protected much easier.

  1. Make all classes final unless you need to subclass them right away.
  2. Make all methods final unless you need to subclass and override them right away.
  3. Make all method parameters final unless you need to change them within the body of the method, which is kinda awkward most of the times anyways.

Now if you're left with a final class, then make everything private unless something is absolutely needed by the world - make that public.

If you're left with a class that does have subclass(es), then carefully examine every property and method. First consider if you even want to expose that property/method to subclasses. If you do, then consider whether a subclass can wreak havoc on your object if it messed up the property value or method implementation in the process of overriding. If it's possible, and you want to protect your class' property/method even from subclasses (sounds ironic, I know), then make it private. Otherwise make it protected.

Disclaimer: I don't program much in Java :)

Call removeView() on the child's parent first

Solution:

((ViewGroup)scrollChildLayout.getParent()).removeView(scrollChildLayout);
//scrollView.removeView(scrollChildLayout);

Use the child element to get a reference to the parent. Cast the parent to a ViewGroup so that you get access to the removeView method and use that.

Thanks to @Dongshengcn for the solution

Resize image in the wiki of GitHub using Markdown

I have used methods described above. Now I am using the method which is a way similiar but more simple to me.

  1. First create add README.md file to your project.
  2. Then upload screenshoots or whatever description images needed to your project main directory.
  3. After uploading image Assets use html to refer these assets directly without using link like below

Like this:

<img src="icon.jpg" width="324" height="324">

<p align="center">
  <img src="screen1.png" width="256" height="455">
  <img src="screen2.png" width="256" height="455">
  <img src="screen3.png" width="256" height="455">
</p>

On above example I have used paragraph to align images side by side. If you are going to use single image just use the code as below

<img src="icon.jpg" width="324" height="324">

Have a nice day!

How to retrieve the dimensions of a view?

I'll just add an alternative solution, override your activity's onWindowFocusChanged method and you will be able to get the values of getHeight(), getWidth() from there.

@Override
public void onWindowFocusChanged (boolean hasFocus) {
        // the height will be set at this point
        int height = myEverySoTallView.getMeasuredHeight(); 
}

How can I change CSS display none or block property using jQuery?

In my case I was doing show / hide elements of a form according to whether an input element was empty or not, so that when hiding the elements the element following the hidden ones was repositioned occupying its space it was necessary to do a float: left of the element of such an element. Even using a plugin as dependsOn it was necessary to use float.

Convert a String representation of a Dictionary to a dictionary?

no any libs are used:

dict_format_string = "{'1':'one', '2' : 'two'}"
d = {}
elems  = filter(str.isalnum,dict_format_string.split("'"))
values = elems[1::2]
keys   = elems[0::2]
d.update(zip(keys,values))

NOTE: As it has hardcoded split("'") will work only for strings where data is "single quoted".

jQuery ajax request being block because Cross-Origin

I solved this by changing the file path in the browser:

  • Instead of: c/XAMPP/htdocs/myfile.html
  • I wrote: localhost/myfile.html

How to delete a localStorage item when the browser window/tab is closed?

for (let i = 0; i < localStorage.length; i++) {
    if (localStorage.key(i).indexOf('the-name-to-delete') > -1) {
        arr.push(localStorage.key(i));
    }
}

for (let i = 0; i < arr.length; i++) {
    localStorage.removeItem(arr[i]);
}

LINQ select one field from list of DTO objects to array

I think you're looking for;

  string[] skus = myLines.Select(x => x.Sku).ToArray();

However, if you're going to iterate over the sku's in subsequent code I recommend not using the ToArray() bit as it forces the queries execution prematurely and makes the applications performance worse. Instead you can just do;

  var skus = myLines.Select(x => x.Sku); // produce IEnumerable<string>

  foreach (string sku in skus) // forces execution of the query

Adding double quote delimiters into csv file

In Excel for Mac at least, you can do this by saving as "CSV for MS DOS" which adds double quotes for any field which needs them.

Install Qt on Ubuntu

Also take a look at awesome project aqtinstall https://github.com/miurahr/aqtinstall/ (it can install any Qt version on Linux, Mac and Windows machines without any interaction!) and GitHub Action that uses this tool: https://github.com/jurplel/install-qt-action

Changing PowerShell's default output encoding to UTF-8

To be short, use:

write-output "your text" | out-file -append -encoding utf8 "filename"

Convert int to ASCII and back in Python

If multiple characters are bound inside a single integer/long, as was my issue:

s = '0123456789'
nchars = len(s)
# string to int or long. Type depends on nchars
x = sum(ord(s[byte])<<8*(nchars-byte-1) for byte in range(nchars))
# int or long to string
''.join(chr((x>>8*(nchars-byte-1))&0xFF) for byte in range(nchars))

Yields '0123456789' and x = 227581098929683594426425L

Sending arrays with Intent.putExtra

final static String EXTRA_MESSAGE = "edit.list.message";

Context context;
public void onClick (View view)
{   
    Intent intent = new Intent(this,display.class);
    RelativeLayout relativeLayout = (RelativeLayout) view.getParent();

    TextView textView = (TextView) relativeLayout.findViewById(R.id.textView1);
    String message = textView.getText().toString();

    intent.putExtra(EXTRA_MESSAGE,message);
    startActivity(intent);
}

Using Composer's Autoload

In my opinion, Sergiy's answer should be the selected answer for the given question. I'm sharing my understanding.

I was looking to autoload my package files using composer which I have under the dir structure given below.

<web-root>
    |--------src/
    |           |--------App/
    |           |
    |           |--------Test/
    |
    |---------library/
    |
    |---------vendor/
    |           |
    |           |---------composer/
    |           |           |---------autoload_psr4.php
    |           |           
    |           |----------autoload.php
    |
    |-----------composer.json
    |

I'm using psr-4 autoloading specification.

Had to add below lines to the project's composer.json. I intend to place my class files inside src/App , src/Test and library directory.

"autoload": {
        "psr-4": {
            "OrgName\\AppType\\AppName\\": ["src/App", "src/Test", "library/"]
        }
    } 

This is pretty much self explaining. OrgName\AppType\AppName is my intended namespace prefix. e.g for class User in src/App/Controller/Provider/User.php -

namespace OrgName\AppType\AppName\Controller\Provider; // namespace declaration

use OrgName\AppType\AppName\Controller\Provider\User; // when using the class

Also notice "src/App", "src/Test" .. are from your web-root that is where your composer.json is. Nothing to do with the vendor dir. take a look at vendor/autoload.php

Now if composer is installed properly all that is required is #composer update

After composer update my classes loaded successfully. What I observed is that composer is adding a line in vendor/composer/autoload_psr4.php

$vendorDir = dirname(dirname(__FILE__));
$baseDir = dirname($vendorDir);

return array(
    'Monolog\\' => array($vendorDir . '/monolog/monolog/src/Monolog'),
    'OrgName\\AppType\\AppName\\' => array($baseDir . '/src/App', $baseDir . '/src/Test', $baseDir . '/library'),
);

This is how composer maps. For psr-0 mapping is in vendor/composer/autoload_classmap.php

When to choose mouseover() and hover() function?

From the official jQuery documentation

  • .mouseover()
    Bind an event handler to the "mouseover" JavaScript event, or trigger that event on an element.

  • .hover() Bind one or two handlers to the matched elements, to be executed when the mouse pointer enters and leaves the elements.

    Calling $(selector).hover(handlerIn, handlerOut) is shorthand for: $(selector).mouseenter(handlerIn).mouseleave(handlerOut);


  • .mouseenter()

    Bind an event handler to be fired when the mouse enters an element, or trigger that handler on an element.

    mouseover fires when the pointer moves into the child element as well, while mouseenter fires only when the pointer moves into the bound element.


What this means

Because of this, .mouseover() is not the same as .hover(), for the same reason .mouseover() is not the same as .mouseenter().

$('selector').mouseover(over_function) // may fire multiple times

// enter and exit functions only called once per element per entry and exit
$('selector').hover(enter_function, exit_function) 

starting file download with JavaScript

If this is your own server application then i suggest using the following header

Content-disposition: attachment; filename=fname.ext

This will force any browser to download the file and not render it in the browser window.

Does file_get_contents() have a timeout setting?

For prototyping, using curl from the shell with the -m parameter allow to pass milliseconds, and will work in both cases, either the connection didn't initiate, error 404, 500, bad url, or the whole data wasn't retrieved in full in the allowed time range, the timeout is always effective. Php won't ever hang out.

Simply don't pass unsanitized user data in the shell call.

system("curl -m 50 -X GET 'https://api.kraken.com/0/public/OHLC?pair=LTCUSDT&interval=60' -H  'accept: application/json' > data.json");
// This data had been refreshed in less than 50ms
var_dump(json_decode(file_get_contents("data.json"),true));

jQuery click event not working in mobile browsers

You can use jQuery Mobile vclick event:

Normalized event for handling touchend or mouse click events on touch devices.

$(document).ready(function(){
   $('.publications').vclick(function() {
       $('#filter_wrapper').show();
   });
 });

CLEAR SCREEN - Oracle SQL Developer shortcut?

To clear the SQL window you can use:

clear screen;

which can also be shortened to

cl scr;

How to zero pad a sequence of integers in bash so that all have the same width?

Use awk like this:

awk -v start=1 -v end=10 'BEGIN{for (i=start; i<=end; i++) printf("%05d\n", i)}'

OUTPUT:

00001
00002
00003
00004
00005
00006
00007
00008
00009
00010

Update:

As pure bash alternative you can do this to get same output:

for i in {1..10}
do
   printf "%05d\n" $i
done

This way you can avoid using an external program seq which is NOT available on all the flavors of *nix.

How do I set up Vim autoindentation properly for editing Python files?

for more advanced python editing consider installing the simplefold vim plugin. it allows you do advanced code folding using regular expressions. i use it to fold my class and method definitions for faster editing.

XPath: select text node

your xpath should work . i have tested your xpath and mine in both MarkLogic and Zorba Xquery/ Xpath implementation.

Both should work.

/node/child::text()[1] - should return Text1
/node/child::text()[2] - should return text2


/node/text()[1] - should return Text1
/node/text()[2] - should return text2

background:none vs background:transparent what is the difference?

To complement the other answers: if you want to reset all background properties to their initial value (which includes background-color: transparent and background-image: none) without explicitly specifying any value such as transparent or none, you can do so by writing:

background: initial;

What is the => assignment in C# in a property signature

Ok... I made a comment that they were different but couldn't explain exactly how but now I know.

String Property { get; } = "value";

is not the same as

String Property => "value";

Here's the difference...

When you use the auto initializer the property creates the instance of value and uses that value persistently. In the above post there is a broken link to Bill Wagner, that explains this well, and I searched the correct link to understand it myself.

In my situation I had my property auto initialize a command in a ViewModel for a View. I changed the property to use expression bodied initializer and the command CanExecute stopped working.

Here's what it looked like and here's what was happening.

Command MyCommand { get; } = new Command();  //works

here's what I changed it to.

Command MyCommand => new Command();  //doesn't work properly

The difference here is when I use { get; } = I create and reference the SAME command in that property. When I use => I actually create a new command and return it every time the property is called. Therefore, I could never update the CanExecute on my command because I was always telling it to update a new reference of that command.

{ get; } = // same reference
=>         // new reference

All that said, if you are just pointing to a backing field then it works fine. This only happens when the auto or expression body creates the return value.

How to pass a null variable to a SQL Stored Procedure from C#.net code

You can pass the DBNull.Value into the parameter's .Value property:

    SqlParameters[0] = new SqlParameter("LedgerID", SqlDbType.BigInt );
    SqlParameters[0].Value = DBNull.Value;

Just adjust for your two DateTime parameters, obviously - just showing how to use the DBNull.Value property value here.

Marc

How can I use querySelector on to pick an input element by name?

I know this is old, but I recently faced the same issue and I managed to pick the element by accessing only the attribute like this: document.querySelector('[name="your-selector-name-here"]');

Just in case anyone would ever need this :)

Recursion or Iteration?

In C++ if the recursive function is a templated one, then the compiler has more chance to optimize it, as all the type deduction and function instantiations will occur in compile time. Modern compilers can also inline the function if possible. So if one uses optimization flags like -O3 or -O2 in g++, then recursions may have the chance to be faster than iterations. In iterative codes, the compiler gets less chance to optimize it, as it is already in the more or less optimal state (if written well enough).

In my case, I was trying to implement matrix exponentiation by squaring using Armadillo matrix objects, in both recursive and iterative way. The algorithm can be found here... https://en.wikipedia.org/wiki/Exponentiation_by_squaring. My functions were templated and I have calculated 1,000,000 12x12 matrices raised to the power 10. I got the following result:

iterative + optimisation flag -O3 -> 2.79.. sec
recursive + optimisation flag -O3 -> 1.32.. sec

iterative + No-optimisation flag  -> 2.83.. sec
recursive + No-optimisation flag  -> 4.15.. sec

These results have been obtained using gcc-4.8 with c++11 flag (-std=c++11) and Armadillo 6.1 with Intel mkl. Intel compiler also shows similar results.

How can I make a link from a <td> table cell

I would recommend using an actual anchor element, and set it as block.

<div class="divBox">
    <a href="#">Link</a>
</div>

.divBox
{
    width: 300px;
    height: 100px;
}
.divBox a
{
    width: 100%;
    height: 100%;
    display: block;
}

This will set the anchor to the same dimensions of the parent div.

Ruby on Rails: How do I add placeholder text to a f.text_field?

I tried the solutions above and it looks like on rails 5.* the second agument by default is the value of the input form, what worked for me was:

text_field_tag :attr, "", placeholder: "placeholder text"

JavaScript - XMLHttpRequest, Access-Control-Allow-Origin errors

I've gotten same problem. The servers logs showed:

DEBUG: <-- origin: null

I've investigated that and it occurred that this is not populated when I've been calling from file from local drive. When I've copied file to the server and used it from server - the request worked perfectly fine

Error occurred during initialization of boot layer FindException: Module not found

I faced same problem when I updated the Java version to 12.x. I was executing my project through Eclipse IDE. I am not sure whether this error is caused by compatibility issues.

However, I removed 12.x from my system and installed 8.x and my project started working fine.

Export javascript data to CSV file without server interaction

See adeneo's answer, but don't forget encodeURIComponent!

a.href     = 'data:application/csv;charset=utf-8,' + encodeURIComponent(csvString);

Also, I needed to do "\r\n" not just "\n" for the row delimiter.

var csvString = csvRows.join("\r\n");

Revised fiddle: http://jsfiddle.net/7Q3c6/

How to automatically generate unique id in SQL like UID12345678?

The only viable solution in my opinion is to use

  • an ID INT IDENTITY(1,1) column to get SQL Server to handle the automatic increment of your numeric value
  • a computed, persisted column to convert that numeric value to the value you need

So try this:

CREATE TABLE dbo.tblUsers
  (ID INT IDENTITY(1,1) NOT NULL PRIMARY KEY CLUSTERED,
   UserID AS 'UID' + RIGHT('00000000' + CAST(ID AS VARCHAR(8)), 8) PERSISTED,
   .... your other columns here....
  )

Now, every time you insert a row into tblUsers without specifying values for ID or UserID:

INSERT INTO dbo.tblUsersCol1, Col2, ..., ColN)
VALUES (Val1, Val2, ....., ValN)

then SQL Server will automatically and safely increase your ID value, and UserID will contain values like UID00000001, UID00000002,...... and so on - automatically, safely, reliably, no duplicates.

Update: the column UserID is computed - but it still OF COURSE has a data type, as a quick peek into the Object Explorer reveals:

enter image description here

Create an Android GPS tracking application

The source code for the Android mobile application open-gpstracker which you appreciated is available here.

You can checkout the code using SVN client application or via Git:

Debugging the source code will surely help you.

Pass Parameter to Gulp Task

It's a feature programs cannot stay without. You can try yargs.

npm install --save-dev yargs

You can use it like this:

gulp mytask --production --test 1234

In the code, for example:

var argv = require('yargs').argv;
var isProduction = (argv.production === undefined) ? false : true;

For your understanding:

> gulp watch
console.log(argv.production === undefined);  <-- true
console.log(argv.test === undefined);        <-- true

> gulp watch --production
console.log(argv.production === undefined);  <-- false
console.log(argv.production);                <-- true
console.log(argv.test === undefined);        <-- true
console.log(argv.test);                      <-- undefined

> gulp watch --production --test 1234
console.log(argv.production === undefined);  <-- false
console.log(argv.production);                <-- true
console.log(argv.test === undefined);        <-- false
console.log(argv.test);                      <-- 1234

Hope you can take it from here.

There's another plugin that you can use, minimist. There's another post where there's good examples for both yargs and minimist: (Is it possible to pass a flag to Gulp to have it run tasks in different ways?)

Could not load file or assembly 'Microsoft.ReportViewer.WebForms'

In order to Run Report Viewer On server with Data from Server

A) Go to Project Property ----> Select Reference ------> Add Reference

1) Import (Microsoft.ReportViewer.Common.dll)-----> (Path "C:\Program Files (x86)\Microsoft Visual Studio 10.0\ReportViewer")

2) Import (Microsoft.ReportViewer.ProcessingObjectModel.dll) -----> (Path "C:\Windows\Assembly\GAC_MSIL\Microsoft.ReportViewer.ProcessingObjectModel")

3) Import (Microsoft.ReportViewer.WebForms.dll)-----> (Path "C:\Program Files (x86)\Microsoft Visual Studio 10.0\ReportViewer")

B) In Above three DLL set its "Local Copy" to True so that while Building Deployment Package it will getcopied to "Bin" folder.

C) Publish the Solution

D) After that Upload all the files along with "Bin" folder with the help of "File Zilla" software to "Web Server".

E) This will install DLL on server hence, client is not required to have "Report Viewer.dll".

This worked for me.

Detect Browser Language in PHP

why dont you keep it simple and clean

<?php
    $lang = substr($_SERVER['HTTP_ACCEPT_LANGUAGE'], 0, 2);
    $acceptLang = ['fr', 'it', 'en']; 
    $lang = in_array($lang, $acceptLang) ? $lang : 'en';
    require_once "index_{$lang}.php"; 

?>

How to convert an ASCII character into an int in C

Use the ASCII to Integer atoi() function which accepts a string and converts it into an integer:

#include <stdlib.h>

int num = atoi("23"); // 23

If the string contains a decimal, the number will be truncated:

int num = atoi("23.21"); // 23