Programs & Examples On #Pretty urls

Modify SVG fill color when being served as Background-Image

 .icon { 
  width: 48px;
  height: 48px;
  display: inline-block;
  background: url(https://s3-us-west-2.amazonaws.com/s.cdpn.io/18515/heart.svg) no-repeat 50% 50%; 
  background-size: cover;
}

.icon-orange { 
  -webkit-filter: hue-rotate(40deg) saturate(0.5) brightness(390%) saturate(4); 
  filter: hue-rotate(40deg) saturate(0.5) brightness(390%) saturate(4); 
}

.icon-yellow {
  -webkit-filter: hue-rotate(70deg) saturate(100);
  filter: hue-rotate(70deg) saturate(100);
}

codeben article and demo

Clone private git repo with dockerfile

For bitbucket repository, generate App Password (Bitbucket settings -> Access Management -> App Password, see the image) with read access to the repo and project.

bitbucket user menu

Then the command that you should use is:

git clone https://username:[email protected]/reponame/projectname.git

AngularJS $watch window resize inside directive

// Following is angular 2.0 directive for window re size that adjust scroll bar for give element as per your tag

---- angular 2.0 window resize directive.
import { Directive, ElementRef} from 'angular2/core';

@Directive({
       selector: '[resize]',
       host: { '(window:resize)': 'onResize()' } // Window resize listener
})

export class AutoResize {

element: ElementRef; // Element that associated to attribute.
$window: any;
       constructor(_element: ElementRef) {

         this.element = _element;
         // Get instance of DOM window.
         this.$window = angular.element(window);

         this.onResize();

    }

    // Adjust height of element.
    onResize() {
         $(this.element.nativeElement).css('height', (this.$window.height() - 163) + 'px');
   }
}

Write to CSV file and export it?

Here's a very simple free open-source CsvExport class for C#. There's an ASP.NET MVC example at the bottom.

https://github.com/jitbit/CsvExport

It takes care about line-breaks, commas, escaping quotes, MS Excel compatibilty... Just add one short .cs file to your project and you're good to go.

(disclaimer: I'm one of the contributors)

Why can I not create a wheel in python?

Install the wheel package first:

pip install wheel

The documentation isn't overly clear on this, but "the wheel project provides a bdist_wheel command for setuptools" actually means "the wheel package...".

How to get current location in Android

I'm using this tutorial and it works nicely for my application.

In my activity I put this code:

GPSTracker tracker = new GPSTracker(this);
    if (!tracker.canGetLocation()) {
        tracker.showSettingsAlert();
    } else {
        latitude = tracker.getLatitude();
        longitude = tracker.getLongitude();
    }

also check if your emulator runs with Google API

Viewing all defined variables

If possible, you may want to use IPython.

To get a list of all current user-defined variables, IPython provides a magic command named who (magics must be prefixed with the modulo character unless the automagic feature is enabled):

In [1]: foo = 'bar'
In [2]: %who
foo

You can use the whos magic to get more detail:

In [3]: %whos
Variable   Type    Data/Info
----------------------------
foo        str     bar

There are a wealth of other magics available. IPython is basically the Python interpreter on steroids. One convenient magic is store, which lets you save variables between sessions (using pickle).

Note: I am not associated with IPython Dev - just a satisfied user.

Edit:

You can find all the magic commands in the IPython Documentation.

This article also has a helpful section on the use of magic commands in Jupyter Notebook

converting epoch time with milliseconds to datetime

Use datetime.datetime.fromtimestamp:

>>> import datetime
>>> s = 1236472051807 / 1000.0
>>> datetime.datetime.fromtimestamp(s).strftime('%Y-%m-%d %H:%M:%S.%f')
'2009-03-08 09:27:31.807000'

%f directive is only supported by datetime.datetime.strftime, not by time.strftime.

UPDATE Alternative using %, str.format:

>>> import time
>>> s, ms = divmod(1236472051807, 1000)  # (1236472051, 807)
>>> '%s.%03d' % (time.strftime('%Y-%m-%d %H:%M:%S', time.gmtime(s)), ms)
'2009-03-08 00:27:31.807'
>>> '{}.{:03d}'.format(time.strftime('%Y-%m-%d %H:%M:%S', time.gmtime(s)), ms)
'2009-03-08 00:27:31.807'

What is the best way to remove a table row with jQuery?

Is the following acceptable:

$('#myTableRow').remove();

The breakpoint will not currently be hit. No symbols have been loaded for this document in a Silverlight application

Delete the .xap file if your breakpoint aren't being hit. Inside YourProject.Web/ClientBin Delete YourProject.xap. I've have tried all above and stumble across this fix, works everytime. Wise to clean the project after deleting as well.

How to get an element's top position relative to the browser's viewport?

On my case, just to be safe regarding scrolling, I added the window.scroll to the equation:

var element = document.getElementById('myElement');
var topPos = element.getBoundingClientRect().top + window.scrollY;
var leftPos = element.getBoundingClientRect().left + window.scrollX;

That allows me to get the real relative position of element on document, even if it has been scrolled.

Rewrite left outer join involving multiple tables from Informix to Oracle

I'm guessing that you want something like

SELECT tab1.a, tab2.b, tab3.c, tab4.d
  FROM table1 tab1 
       JOIN table2 tab2 ON (tab1.fg = tab2.fg)
       LEFT OUTER JOIN table4 tab4 ON (tab1.ss = tab4.ss)
       LEFT OUTER JOIN table3 tab3 ON (tab4.xya = tab3.xya and tab3.desc = 'XYZ')
       LEFT OUTER JOIN table5 tab5 on (tab4.kk = tab5.kk AND
                                       tab3.dd = tab5.dd)

Difference between 2 dates in SQLite

The SQLite documentation is a great reference and the DateAndTimeFunctions page is a good one to bookmark.

It's also helpful to remember that it's pretty easy to play with queries with the sqlite command line utility:

sqlite> select julianday(datetime('now'));
2454788.09219907
sqlite> select datetime(julianday(datetime('now')));
2008-11-17 14:13:55

You cannot call a method on a null-valued expression

The simple answer for this one is that you have an undeclared (null) variable. In this case it is $md5. From the comment you put this needed to be declared elsewhere in your code

$md5 = new-object -TypeName System.Security.Cryptography.MD5CryptoServiceProvider

The error was because you are trying to execute a method that does not exist.

PS C:\Users\Matt> $md5 | gm


   TypeName: System.Security.Cryptography.MD5CryptoServiceProvider

Name                       MemberType Definition                                                                                                                            
----                       ---------- ----------                                                                                                                            
Clear                      Method     void Clear()                                                                                                                          
ComputeHash                Method     byte[] ComputeHash(System.IO.Stream inputStream), byte[] ComputeHash(byte[] buffer), byte[] ComputeHash(byte[] buffer, int offset, ...

The .ComputeHash() of $md5.ComputeHash() was the null valued expression. Typing in gibberish would create the same effect.

PS C:\Users\Matt> $bagel.MakeMeABagel()
You cannot call a method on a null-valued expression.
At line:1 char:1
+ $bagel.MakeMeABagel()
+ ~~~~~~~~~~~~~~~~~~~~~
    + CategoryInfo          : InvalidOperation: (:) [], RuntimeException
    + FullyQualifiedErrorId : InvokeMethodOnNull

PowerShell by default allows this to happen as defined its StrictMode

When Set-StrictMode is off, uninitialized variables (Version 1) are assumed to have a value of 0 (zero) or $Null, depending on type. References to non-existent properties return $Null, and the results of function syntax that is not valid vary with the error. Unnamed variables are not permitted.

Create an Array of Arraylists

You can do this :

//Create an Array of type ArrayList

`ArrayList<Integer>[] a = new ArrayList[n];`

//For each element in array make an ArrayList

for(int i=0; i<n; i++){ 
    a[i] = new ArrayList<Integer>();
}

Using a RegEx to match IP addresses in Python

def ipcheck():
# 1.Validate the ip adderess
input_ip = input('Enter the ip:')
flag = 0

pattern = "^\d{1,3}.\d{1,3}.\d{1,3}.\d{1,3}$"
match = re.match(pattern, input_ip)
if (match):
    field = input_ip.split(".")
    for i in range(0, len(field)):
        if (int(field[i]) < 256):
            flag += 1
        else:
            flag = 0
if (flag == 4):
    print("valid ip")
else:
    print('No match for ip or not a valid ip')

How to get absolute path to file in /resources folder of your project

There are two problems on our way to the absolute path:

  1. The placement found will be not where the source files lie, but where the class is saved. And the resource folder almost surely will lie somewhere in the source folder of the project.
  2. The same functions for retrieving the resource work differently if the class runs in a plugin or in a package directly in the workspace.

The following code will give us all useful paths:

    URL localPackage = this.getClass().getResource("");
    URL urlLoader = YourClassName.class.getProtectionDomain().getCodeSource().getLocation();
    String localDir = localPackage.getPath();
    String loaderDir = urlLoader.getPath();
    System.out.printf("loaderDir = %s\n localDir = %s\n", loaderDir, localDir);

Here both functions that can be used for localization of the resource folder are researched. As for class, it can be got in either way, statically or dynamically.


If the project is not in the plugin, the code if run in JUnit, will print:

loaderDir = /C:.../ws/source.dir/target/test-classes/
 localDir = /C:.../ws/source.dir/target/test-classes/package/

So, to get to src/rest/resources we should go up and down the file tree. Both methods can be used. Notice, we can't use getResource(resourceFolderName), for that folder is not in the target folder. Nobody puts resources in the created folders, I hope.


If the class is in the package that is in the plugin, the output of the same test will be:

loaderDir = /C:.../ws/plugin/bin/
 localDir = /C:.../ws/plugin/bin/package/

So, again we should go up and down the folder tree.


The most interesting is the case when the package is launched in the plugin. As JUnit plugin test, for our example. The output is:

loaderDir = /C:.../ws/plugin/
 localDir = /package/

Here we can get the absolute path only combining the results of both functions. And it is not enough. Between them we should put the local path of the place where the classes packages are, relatively to the plugin folder. Probably, you will have to insert something as src or src/test/resource here.

You can insert the code into yours and see the paths that you have.

How to POST JSON request using Apache HttpClient?

For Apache HttpClient 4.5 or newer version:

    CloseableHttpClient httpclient = HttpClients.createDefault();
    HttpPost httpPost = new HttpPost("http://targethost/login");
    String JSON_STRING="";
    HttpEntity stringEntity = new StringEntity(JSON_STRING,ContentType.APPLICATION_JSON);
    httpPost.setEntity(stringEntity);
    CloseableHttpResponse response2 = httpclient.execute(httpPost);

Note:

1 in order to make the code compile, both httpclient package and httpcore package should be imported.

2 try-catch block has been ommitted.

Reference: appache official guide

the Commons HttpClient project is now end of life, and is no longer being developed. It has been replaced by the Apache HttpComponents project in its HttpClient and HttpCore modules

How to disable scrolling in UITableView table when the content fits on the screen

You can edit this in your storyboard (if you are using one). Under the table view there is a checkbox that says "Scrolling Enabled". Uncheck it and you're done.

LINQ Where with AND OR condition

Linq With Or Condition by using Lambda expression you can do as below

DataTable dtEmp = new DataTable();

dtEmp.Columns.Add("EmpID", typeof(int));
dtEmp.Columns.Add("EmpName", typeof(string));
dtEmp.Columns.Add("Sal", typeof(decimal));
dtEmp.Columns.Add("JoinDate", typeof(DateTime));
dtEmp.Columns.Add("DeptNo", typeof(int));

dtEmp.Rows.Add(1, "Rihan", 10000, new DateTime(2001, 2, 1), 10);
dtEmp.Rows.Add(2, "Shafi", 20000, new DateTime(2000, 3, 1), 10);
dtEmp.Rows.Add(3, "Ajaml", 25000, new DateTime(2010, 6, 1), 10);
dtEmp.Rows.Add(4, "Rasool", 45000, new DateTime(2003, 8, 1), 20);
dtEmp.Rows.Add(5, "Masthan", 22000, new DateTime(2001, 3, 1), 20);


var res2 = dtEmp.AsEnumerable().Where(emp => emp.Field<int>("EmpID")
            == 1 || emp.Field<int>("EmpID") == 2);

foreach (DataRow row in res2)
{
    Label2.Text += "Emplyee ID: " + row[0] + "   &   Emplyee Name: " + row[1] + ",  ";
}

Hide scroll bar, but while still being able to scroll

HTML:

<div class="parent">
    <div class="child">
    </div>
</div>

CSS:

.parent{
    position: relative;
    width: 300px;
    height: 150px;
    border: 1px solid black;
    overflow: hidden;
}

.child {
    height: 150px;   
    width: 318px;
    overflow-y: scroll;
}

Apply CSS accordingly.

Check it here (tested in Internet Explorer and Firefox).

If list index exists, do X

Using the length of the list would be the fastest solution to check if an index exists:

def index_exists(ls, i):
    return (0 <= i < len(ls)) or (-len(ls) <= i < 0)

This also tests for negative indices, and most sequence types (Like ranges and strs) that have a length.

If you need to access the item at that index afterwards anyways, it is easier to ask forgiveness than permission, and it is also faster and more Pythonic. Use try: except:.

try:
    item = ls[i]
    # Do something with item
except IndexError:
    # Do something without the item

This would be as opposed to:

if index_exists(ls, i):
    item = ls[i]
    # Do something with item
else:
    # Do something without the item

Getting reference to the top-most view/window in iOS application

If your application only works in portrait orientation, this is enough:

[[[UIApplication sharedApplication] keyWindow] addSubview:yourView]

And your view will not be shown over keyboard and status bar.

If you want to get a topmost view that over keyboard or status bar, or you want the topmost view can rotate correctly with devices, please try this framework:

https://github.com/HarrisonXi/TopmostView

It supports iOS7/8/9.

What is the alternative for ~ (user's home directory) on Windows command prompt?

If you want a shorter version of Jay's you could try

    set usr=%userprofile%
    cd %usr%

Or you could even use %u% if you wanted to. It saves some keystrokes anyway.

Get real path from URI, Android KitKat new storage access framework

Here is an updated version of Paul Burke's answer. In versions below Android 4.4 (KitKat) we don't have the DocumentsContract class.

In order to work on versions below KitKat create this class:

public class DocumentsContract {
    private static final String DOCUMENT_URIS =
        "com.android.providers.media.documents " +
        "com.android.externalstorage.documents " +
        "com.android.providers.downloads.documents " +
        "com.android.providers.media.documents";

    private static final String PATH_DOCUMENT = "document";
    private static final String TAG = DocumentsContract.class.getSimpleName();

    public static String getDocumentId(Uri documentUri) {
        final List<String> paths = documentUri.getPathSegments();
        if (paths.size() < 2) {
            throw new IllegalArgumentException("Not a document: " + documentUri);
        }

        if (!PATH_DOCUMENT.equals(paths.get(0))) {
            throw new IllegalArgumentException("Not a document: " + documentUri);
        }
        return paths.get(1);
    }

    public static boolean isDocumentUri(Uri uri) {
        final List<String> paths = uri.getPathSegments();
        Logger.v(TAG, "paths[" + paths + "]");
        if (paths.size() < 2) {
            return false;
        }
        if (!PATH_DOCUMENT.equals(paths.get(0))) {
            return false;
        }
        return DOCUMENT_URIS.contains(uri.getAuthority());
    }
}

Is there a simple, elegant way to define singletons?

See this implementation from PEP318, implementing the singleton pattern with a decorator:

def singleton(cls):
    instances = {}
    def getinstance():
        if cls not in instances:
            instances[cls] = cls()
        return instances[cls]
    return getinstance

@singleton
class MyClass:
    ...

String to date in Oracle with milliseconds

Oracle stores only the fractions up to second in a DATE field.

Use TIMESTAMP instead:

SELECT  TO_TIMESTAMP('2004-09-30 23:53:48,140000000', 'YYYY-MM-DD HH24:MI:SS,FF9')
FROM    dual

, possibly casting it to a DATE then:

SELECT  CAST(TO_TIMESTAMP('2004-09-30 23:53:48,140000000', 'YYYY-MM-DD HH24:MI:SS,FF9') AS DATE)
FROM    dual

git - pulling from specific branch

It's often clearer to separate the two actions git pull does. The first thing it does is update the local tracking branc that corresponds to the remote branch. This can be done with git fetch. The second is that it then merges in changes, which can of course be done with git merge, though other options such as git rebase are occasionally useful.

Setting environment variables via launchd.conf no longer works in OS X Yosemite/El Capitan/macOS Sierra/Mojave?

You can give https://github.com/ersiner/osx-env-sync a try. It handles both command line and GUI apps from a single source and works withe the latest version of OS X (Yosemite).

You can use path substitutions and other shell tricks since what you write is regular bash script to be sourced by bash in the first place. No restrictions.. (Check osx-env-sync documentation and you'll understand how it achieves this.)

I answered a similar question here where you'll find more.

Nested JSON: How to add (push) new items to an object?

If your JSON is without key you can do it like this:

library[library.length] = {"foregrounds" : foregrounds,"backgrounds" : backgrounds};

So, try this:

var library = {[{
    "title"       : "Gold Rush",
        "foregrounds" : ["Slide 1","Slide 2","Slide 3"],
        "backgrounds" : ["1.jpg","","2.jpg"]
    }, {
    "title"       : California",
        "foregrounds" : ["Slide 1","Slide 2","Slide 3"],
        "backgrounds" : ["3.jpg","4.jpg","5.jpg"]
    }]
}

Then:

library[library.length] = {"title" : "Gold Rush", "foregrounds" : ["Howdy","Slide 2"], "backgrounds" : ["1.jpg",""]};

calling server side event from html button control

If you are OK with converting the input button to a server side control by specifying runat="server", and you are using asp.net, an option could be using the HtmlButton.OnServerClick property.

<input id="foo "runat="server" type="button" onserverclick="foo_OnClick" />

This should work and call foo_OnClick in your server side code. Also notice that based on Microsoft documentation linked above, you should also be able to use the HTML 4.0 tag.

Google Maps API warning: NoApiKeys

Google maps requires an API key for new projects since june 2016. For more information take a look at the Google Developers Blog. Also more information in german you'll find at this blog post from the clickstorm Blog.

Angular2 @Input to a property with get/set

@Paul Cavacas, I had the same issue and I solved by setting the Input() decorator above the getter.

  @Input('allowDays')
  get in(): any {
    return this._allowDays;
  }

  //@Input('allowDays')
  // not working
  set in(val) {
    console.log('allowDays = '+val);
    this._allowDays = val;
  }

See this plunker: https://plnkr.co/edit/6miSutgTe9sfEMCb8N4p?p=preview

Inline list initialization in VB.NET

Use this syntax for VB.NET 2005/2008 compatibility:

Dim theVar As New List(Of String)(New String() {"one", "two", "three"})

Although the VB.NET 2010 syntax is prettier.

Get current scroll position of ScrollView in React Native

Try.

<ScrollView onScroll={this.handleScroll} />

And then:

handleScroll: function(event: Object) {
 console.log(event.nativeEvent.contentOffset.y);
},

Count Vowels in String Python

count = 0
s = "azcbobobEgghakl"
s = s.lower()
for i in range(0, len(s)):
    if s[i] == 'a'or s[i] == 'e'or s[i] == 'i'or s[i] == 'o'or s[i] == 'u':
        count += 1
print("Number of vowels: "+str(count))

Python: finding an element in a list

I use function for returning index for the matching element (Python 2.6):

def index(l, f):
     return next((i for i in xrange(len(l)) if f(l[i])), None)

Then use it via lambda function for retrieving needed element by any required equation e.g. by using element name.

element = mylist[index(mylist, lambda item: item["name"] == "my name")]

If i need to use it in several places in my code i just define specific find function e.g. for finding element by name:

def find_name(l, name):
     return l[index(l, lambda item: item["name"] == name)]

And then it is quite easy and readable:

element = find_name(mylist,"my name")

How to Deep clone in javascript

There should be no real world need for such a function anymore. This is mere academic interest.

As purely an exercise, this is a more functional way of doing it. It's an extension of @tfmontague's answer as I'd suggested adding a guard block there. But seeing as I feel compelled to ES6 and functionalise all the things, here's my pimped version. It complicates the logic as you have to map over the array and reduce over the object, but it avoids any mutations.

_x000D_
_x000D_
const cloner = (x) => {
    const recurseObj = x => (typeof x === 'object') ? cloner(x) : x
    const cloneObj = (y, k) => {
        y[k] = recurseObj(x[k])
        return y
    }
    // Guard blocks
    // Add extra for Date / RegExp if you want
    if (!x) {
        return x
    }
    if (Array.isArray(x)) {
        return x.map(recurseObj)
    }
    return Object.keys(x).reduce(cloneObj, {})
}
const tests = [
    null,
    [],
    {},
    [1,2,3],
    [1,2,3, null],
    [1,2,3, null, {}],
    [new Date('2001-01-01')], // FAIL doesn't work with Date
    {x:'', y: {yx: 'zz', yy: null}, z: [1,2,3,null]},
    {
        obj : new function() {
            this.name = "Object test";
        }
    } // FAIL doesn't handle functions
]
tests.map((x,i) => console.log(i, cloner(x)))
_x000D_
_x000D_
_x000D_

Get combobox value in Java swing

If the string is empty, comboBox.getSelectedItem().toString() will give a NullPointerException. So better to typecast by (String).

Can I get Unix's pthread.h to compile in Windows?

There are, as i recall, two distributions of the gnu toolchain for windows: mingw and cygwin.

I'd expect cygwin work - a lot of effort has been made to make that a "stadard" posix environment.

The mingw toolchain uses msvcrt.dll for its runtime and thus will probably expose msvcrt's "thread" api: _beginthread which is defined in <process.h>

Oracle PL/SQL : remove "space characters" from a string

I'd go for regexp_replace, although I'm not 100% sure this is usable in PL/SQL

my_value := regexp_replace(my_value, '[[:space:]]*',''); 

Capture characters from standard input without waiting for enter to be pressed

I use kbhit() to see if a char is present and then getchar() to read the data. On windows, you can use "conio.h". On linux, you will have to implement your own kbhit().

See code below:

// kbhit
#include <stdio.h>
#include <sys/ioctl.h> // For FIONREAD
#include <termios.h>
#include <stdbool.h>

int kbhit(void) {
    static bool initflag = false;
    static const int STDIN = 0;

    if (!initflag) {
        // Use termios to turn off line buffering
        struct termios term;
        tcgetattr(STDIN, &term);
        term.c_lflag &= ~ICANON;
        tcsetattr(STDIN, TCSANOW, &term);
        setbuf(stdin, NULL);
        initflag = true;
    }

    int nbbytes;
    ioctl(STDIN, FIONREAD, &nbbytes);  // 0 is STDIN
    return nbbytes;
}

// main
#include <unistd.h>

int main(int argc, char** argv) {
    char c;
    //setbuf(stdout, NULL); // Optional: No buffering.
    //setbuf(stdin, NULL);  // Optional: No buffering.
    printf("Press key");
    while (!kbhit()) {
        printf(".");
        fflush(stdout);
        sleep(1);
    }
    c = getchar();
    printf("\nChar received:%c\n", c);
    printf("Done.\n");

    return 0;
}

How to make execution pause, sleep, wait for X seconds in R?

Sys.sleep() will not work if the CPU usage is very high; as in other critical high priority processes are running (in parallel).

This code worked for me. Here I am printing 1 to 1000 at a 2.5 second interval.

for (i in 1:1000)
{
  print(i)
  date_time<-Sys.time()
  while((as.numeric(Sys.time()) - as.numeric(date_time))<2.5){} #dummy while loop
}

How do you use variables in a simple PostgreSQL script?

Building on @nad2000's answer and @Pavel's answer here, this is where I ended up for my Flyway migration scripts. Handling for scenarios where the database schema was manually modified.

DO $$
BEGIN
    IF NOT EXISTS(
        SELECT TRUE FROM pg_attribute 
        WHERE attrelid = (
            SELECT c.oid
            FROM pg_class c
            JOIN pg_namespace n ON n.oid = c.relnamespace
            WHERE 
                n.nspname = CURRENT_SCHEMA() 
                AND c.relname = 'device_ip_lookups'
            )
        AND attname = 'active_date'
        AND NOT attisdropped
        AND attnum > 0
        )
    THEN
        RAISE NOTICE 'ADDING COLUMN';        
        ALTER TABLE device_ip_lookups
            ADD COLUMN active_date TIMESTAMP;
    ELSE
        RAISE NOTICE 'SKIPPING, COLUMN ALREADY EXISTS';
    END IF;
END $$;

How to display images from a folder using php - PHP

You had a mistake on the statement below. Use . not ,

echo '<img src="', $dir, '/', $file, '" alt="', $file, $

to

echo '<img src="'. $dir. '/'. $file. '" alt="'. $file. $

and

echo 'Directory \'', $dir, '\' not found!';

to

echo 'Directory \''. $dir. '\' not found!';

ToList()-- does it create a new list?

Yes, it creates a new list. This is by design.

The list will contain the same results as the original enumerable sequence, but materialized into a persistent (in-memory) collection. This allows you to consume the results multiple times without incurring the cost of recomputing the sequence.

The beauty of LINQ sequences is that they are composable. Often, the IEnumerable<T> you get is the result of combining multiple filtering, ordering, and/or projection operations. Extension methods like ToList() and ToArray() allow you to convert the computed sequence into a standard collection.

How to read single Excel cell value

The issue with reading single Excel Cell in .Net comes from the fact, that the empty cell is evaluated to a Null. Thus, one cannot use its .Value or .Value2 properties, because an error shows up.

To return an empty string, when the cell is Null the Convert.ToString(Cell) can be used in the following way:

Excel.Workbook wkb = Open(excel, filePath);
Excel.Worksheet wk = (Excel.Worksheet)excel.Worksheets.get_Item(1);

for (int i = 1; i < 5; i++)
{
    string a = Convert.ToString(wk.Cells[i, 1].Value2);
    Console.WriteLine(a);
}

How to remove all non-alpha numeric characters from a string in MySQL?

if you are using php then....

try{
$con = new PDO ("mysql:host=localhost;dbname=dbasename","root","");
}
catch(PDOException $e){
echo "error".$e-getMessage();   
}

$select = $con->prepare("SELECT * FROM table");
$select->setFetchMode(PDO::FETCH_ASSOC);
$select->execute();

while($data=$select->fetch()){ 

$id = $data['id'];
$column = $data['column'];
$column = preg_replace("/[^a-zA-Z0-9]+/", " ", $column); //remove all special characters

$update = $con->prepare("UPDATE table SET column=:column WHERE id='$id'");
$update->bindParam(':column', $column );
$update->execute();

// echo $column."<br>";
} 

Mercurial — revert back to old version and continue from there

hg update [-r REV]

If later you commit, you will effectively create a new branch. Then you might continue working only on this branch or eventually merge the existing one into it.

Serializing PHP object to JSON

Following code is doing the job using reflection. It assumes you have getters for the properties you want to serialize

    <?php

    /**
     * Serialize a simple PHP object into json
     * Should be used for POPO that has getter methods for the relevant properties to serialize
     * A property can be simple or by itself another POPO object
     *
     * Class CleanJsonSerializer
     */
    class CleanJsonSerializer {

    /**
     * Local cache of a property getters per class - optimize reflection code if the same object appears several times
     * @var array
     */
    private $classPropertyGetters = array();

    /**
     * @param mixed $object
     * @return string|false
     */
    public function serialize($object)
    {
        return json_encode($this->serializeInternal($object));
    }

    /**
     * @param $object
     * @return array
     */
    private function serializeInternal($object)
    {
        if (is_array($object)) {
            $result = $this->serializeArray($object);
        } elseif (is_object($object)) {
            $result = $this->serializeObject($object);
        } else {
            $result = $object;
        }
        return $result;
    }

    /**
     * @param $object
     * @return \ReflectionClass
     */
    private function getClassPropertyGetters($object)
    {
        $className = get_class($object);
        if (!isset($this->classPropertyGetters[$className])) {
            $reflector = new \ReflectionClass($className);
            $properties = $reflector->getProperties();
            $getters = array();
            foreach ($properties as $property)
            {
                $name = $property->getName();
                $getter = "get" . ucfirst($name);
                try {
                    $reflector->getMethod($getter);
                    $getters[$name] = $getter;
                } catch (\Exception $e) {
                    // if no getter for a specific property - ignore it
                }
            }
            $this->classPropertyGetters[$className] = $getters;
        }
        return $this->classPropertyGetters[$className];
    }

    /**
     * @param $object
     * @return array
     */
    private function serializeObject($object) {
        $properties = $this->getClassPropertyGetters($object);
        $data = array();
        foreach ($properties as $name => $property)
        {
            $data[$name] = $this->serializeInternal($object->$property());
        }
        return $data;
    }

    /**
     * @param $array
     * @return array
     */
    private function serializeArray($array)
    {
        $result = array();
        foreach ($array as $key => $value) {
            $result[$key] = $this->serializeInternal($value);
        }
        return $result;
    }  
} 

Difference between Iterator and Listiterator?

Iterator is super class of ListIterator.

Here are the differences between them:

  1. With iterator you can move only forward, but with ListIterator you can move backword also while reading the elements.
  2. With ListIterator you can obtain the index at any point while traversing, which is not possible with iterators.
  3. With iterator you can check only for next element available or not, but in listiterator you can check previous and next elements.
  4. With listiterator you can add new element at any point of time, while traversing. Not possible with iterator.
  5. With listiterator you can modify an element while traversing, which is not possible with iterator.

Iterator look and feel:

 public interface Iterator<E> {
    boolean hasNext();
    E next();
    void remove(); //optional-->use only once with next(), 
                         dont use it when u use for:each
    }

ListIterator look and feel:

public interface ListIterator<E> extends Iterator<E> {
    boolean hasNext();
    E next();
    boolean hasPrevious();
    E previous();
    int nextIndex();
    int previousIndex();
    void remove(); //optional
    void set(E e); //optional
    void add(E e); //optional
}

Xcode 8 shows error that provisioning profile doesn't include signing certificate

In my case the issue is that on Xcode Beta 11.5 there's a change on the ways to sign the app so just make sure that both for the Debug/Release the provisioning certificate is properly set

Print JSON parsed object?

If you want to debug why not use console debug

window.console.debug(jsonObject);

If conditions in a Makefile, inside a target

You can simply use shell commands. If you want to suppress echoing the output, use the "@" sign. For example:

clean:
    @if [ "test" = "test" ]; then\
        echo "Hello world";\
    fi

Note that the closing ";" and "\" are necessary.

git push rejected: error: failed to push some refs

for me following worked, just ran these command one by one

git pull -r origin master

git push -f origin your_branch

Left-pad printf with spaces

If you want the word "Hello" to print in a column that's 40 characters wide, with spaces padding the left, use the following.

char *ptr = "Hello";
printf("%40s\n", ptr);

That will give you 35 spaces, then the word "Hello". This is how you format stuff when you know how wide you want the column, but the data changes (well, it's one way you can do it).

If you know you want exactly 40 spaces then some text, just save the 40 spaces in a constant and print them. If you need to print multiple lines, either use multiple printf statements like the one above, or do it in a loop, changing the value of ptr each time.

jQuery Event : Detect changes to the html/text of a div

There is no inbuilt solution to this problem, this is a problem with your design and coding pattern.

You can use publisher/subscriber pattern. For this you can use jQuery custom events or your own event mechanism.

First,

function changeHtml(selector, html) {
    var elem = $(selector);
    jQuery.event.trigger('htmlchanging', { elements: elem, content: { current: elem.html(), pending: html} });
    elem.html(html);
    jQuery.event.trigger('htmlchanged', { elements: elem, content: html });
}

Now you can subscribe divhtmlchanging/divhtmlchanged events as follow,

$(document).bind('htmlchanging', function (e, data) {
    //your before changing html, logic goes here
});

$(document).bind('htmlchanged', function (e, data) {
    //your after changed html, logic goes here
});

Now, you have to change your div content changes through this changeHtml() function. So, you can monitor or can do necessary changes accordingly because bind callback data argument containing the information.

You have to change your div's html like this;

changeHtml('#mydiv', '<p>test content</p>');

And also, you can use this for any html element(s) except input element. Anyway you can modify this to use with any element(s).

Get data from fs.readFile

Using Promises with ES7

Asynchronous use with mz/fs

The mz module provides promisified versions of the core node library. Using them is simple. First install the library...

npm install mz

Then...

const fs = require('mz/fs');
fs.readFile('./Index.html').then(contents => console.log(contents))
  .catch(err => console.error(err));

Alternatively you can write them in asynchronous functions:

async function myReadfile () {
  try {
    const file = await fs.readFile('./Index.html');
  }
  catch (err) { console.error( err ) }
};

Selenium WebDriver.get(url) does not open the URL

I got the same error when issuing a URL without the protocol (like localhost:4200) instead of a correct one also specifying the protocol (e.g. http://localhost:4200).

Google Chrome works fine without the protocol (it takes http as the default), but Firefox crashes with this error.

Getting execute permission to xp_cmdshell

tchester said :

(2) Create a login for the non-sysadmin user that has public access to the master database

I went to my user's database list (server/security/connections/my user name/properties/user mapping, and wanted to check the box for master database. I got an error message telling that the user already exists in the master database. Went to master database, dropped the user, went back to "user mapping" and checked the box for master. Check the "public" box below.

After that, you need to re-issue the grant execute on xp_cmdshell to "my user name"

Yves

Get properties of a class

This TypeScript code

class A {
    private a1;
    public a2;
}

compiles to this JavaScript code

class A {
}

That's because properties in JavaScript start extisting only after they have some value. You have to assign the properties some value.

class A {
    private a1 = "";
    public a2 = "";
}

it compiles to

class A {
    constructor() {
        this.a1 = "";
        this.a2 = "";
    }
}

Still, you cannot get the properties from mere class (you can get only methods from prototype). You must create an instance. Then you get the properties by calling Object.getOwnPropertyNames().

let a = new A();
let array = return Object.getOwnPropertyNames(a);

array[0] === "a1";
array[1] === "a2";

Applied to your example

class Describer {
    static describe(instance): Array<string> {
        return Object.getOwnPropertyNames(instance);
    }
}

let a = new A();
let x = Describer.describe(a);

Why can't overriding methods throw exceptions broader than the overridden method?

The overriding method CAN throw any unchecked (runtime) exception, regardless of whether the overridden method declares the exception

Example:

class Super {
    public void test() {
        System.out.println("Super.test()");
    }
}

class Sub extends Super {
    @Override
    public void test() throws IndexOutOfBoundsException {
        // Method can throw any Unchecked Exception
        System.out.println("Sub.test()");
    }
}

class Sub2 extends Sub {
    @Override
    public void test() throws ArrayIndexOutOfBoundsException {
        // Any Unchecked Exception
        System.out.println("Sub2.test()");
    }
}

class Sub3 extends Sub2 {
    @Override
    public void test() {
        // Any Unchecked Exception or no exception
        System.out.println("Sub3.test()");
    }
}

class Sub4 extends Sub2 {
    @Override
    public void test() throws AssertionError {
        // Unchecked Exception IS-A RuntimeException or IS-A Error
        System.out.println("Sub4.test()");
    }
}

How do I prevent site scraping?

  1. No, it's not possible to stop (in any way)
  2. Embrace it. Why not publish as RDFa and become super search engine friendly and encourage the re-use of data? People will thank you and provide credit where due (see musicbrainz as an example).

It is not the answer you probably want, but why hide what you're trying to make public?

Best way to test exceptions with Assert to ensure they will be thrown

Mark the test with the ExpectedExceptionAttribute (this is the term in NUnit or MSTest; users of other unit testing frameworks may need to translate).

Check if a radio button is checked jquery

First of all, have only one id="test"

Secondly, try this:

if ($('[name="test"]').is(':checked'))

How to use Simple Ajax Beginform in Asp.net MVC 4?

Simple example: Form with textbox and Search button.

If you write "name" into the textbox and submit form, it will brings you patients with "name" in table.

View:

@using (Ajax.BeginForm("GetPatients", "Patient", new AjaxOptions {//GetPatients is name of method in PatientController
    InsertionMode = InsertionMode.Replace, //target element(#patientList) will be replaced
    UpdateTargetId = "patientList",
    LoadingElementId = "loader" // div with .gif loader - that is shown when data are loading   
}))
{
    string patient_Name = "";
    @Html.EditorFor(x=>patient_Name) //text box with name and id, that it will pass to controller
    <input  type="submit" value="Search" />
}

@* ... *@
<div id="loader" class=" aletr" style="display:none">
    Loading...<img src="~/Images/ajax-loader.gif" />
</div>
@Html.Partial("_patientList") @* this is view with patient table. Same view you will return from controller *@

_patientList.cshtml:

@model IEnumerable<YourApp.Models.Patient>

<table id="patientList" >
<tr>
    <th>
        @Html.DisplayNameFor(model => model.Name)
    </th>
    <th>
        @Html.DisplayNameFor(model => model.Number)
    </th>       
</tr>
@foreach (var patient in Model) {
<tr>
    <td>
        @Html.DisplayFor(modelItem => patient.Name)
    </td>
    <td>
        @Html.DisplayFor(modelItem => patient.Number)
    </td>
</tr>
}
</table>

Patient.cs

public class Patient
{
   public string Name { get; set; }
   public int Number{ get; set; }
}

PatientController.cs

public PartialViewResult GetPatients(string patient_Name="")
{
   var patients = yourDBcontext.Patients.Where(x=>x.Name.Contains(patient_Name))
   return PartialView("_patientList", patients);
}

And also as TSmith said in comments, don´t forget to install jQuery Unobtrusive Ajax library through NuGet.

how to convert binary string to decimal?

parseInt() with radix is a best solution (as was told by many):

But if you want to implement it without parseInt, here is an implementation:

  function bin2dec(num){
    return num.split('').reverse().reduce(function(x, y, i){
      return (y === '1') ? x + Math.pow(2, i) : x;
    }, 0);
  }

How do I list all the files in a directory and subdirectories in reverse chronological order?

The command in wfg5475's answer is working properly, just need to add one thing to show only files in a directory & sub directory:

ls -ltraR |egrep -v '\.$|\.\.|\.:|\.\/|total|^d' |sed '/^$/d'

Added one thing: ^d to ignore the all directories from the listing outputs

How to switch to new window in Selenium for Python?

You can do it by using window_handles and switch_to_window method.

Before clicking the link first store the window handle as

window_before = driver.window_handles[0]

after clicking the link store the window handle of newly opened window as

window_after = driver.window_handles[1]

then execute the switch to window method to move to newly opened window

driver.switch_to_window(window_after)

and similarly you can switch between old and new window. Following is the code example

import unittest
from selenium import webdriver

class GoogleOrgSearch(unittest.TestCase):

    def setUp(self):
        self.driver = webdriver.Firefox()

    def test_google_search_page(self):
        driver = self.driver
        driver.get("http://www.cdot.in")
        window_before = driver.window_handles[0]
        print window_before
        driver.find_element_by_xpath("//a[@href='http://www.cdot.in/home.htm']").click()
        window_after = driver.window_handles[1]
        driver.switch_to_window(window_after)
        print window_after
        driver.find_element_by_link_text("ATM").click()
        driver.switch_to_window(window_before)

    def tearDown(self):
        self.driver.close()

if __name__ == "__main__":
    unittest.main()

Auto increment in MongoDB to store sequence of Unique User ID

The best way I found to make this to my purpose was to increment from the max value you have in the field and for that, I used the following syntax:

var array = db.CollectionName.find({}).sort({ _id: -1 }).limit(1).toArray(); var max = max.length?max[0]+1:1;

Even if an User ID is deleted, this wont create duplicate

What is POCO in Entity Framework?

POCOs(Plain old CLR objects) are simply entities of your Domain. Normally when we use entity framework the entities are generated automatically for you. This is great but unfortunately these entities are interspersed with database access functionality which is clearly against the SOC (Separation of concern). POCOs are simple entities without any data access functionality but still gives the capabilities all EntityObject functionalities like

  • Lazy loading
  • Change tracking

Here is a good start for this

POCO Entity framework

You can also generate POCOs so easily from your existing Entity framework project using Code generators.

EF 5.X DbContext code generator

Proper Linq where clauses

Looking under the hood, the two statements will be transformed into different query representations. Depending on the QueryProvider of Collection, this might be optimized away or not.

When this is a linq-to-object call, multiple where clauses will lead to a chain of IEnumerables that read from each other. Using the single-clause form will help performance here.

When the underlying provider translates it into a SQL statement, the chances are good that both variants will create the same statement.

Has Windows 7 Fixed the 255 Character File Path Limit?

See http://msdn.microsoft.com/en-us/library/aa365247(VS.85).aspx

This explains that Unicode versions of Windows APIs have higher limits, and how to enable that.

How do I find which process is leaking memory?

I suggest the use of htop, as a better alternative to top.

One line if statement not working

From what I know

3 one-liners

  1. a = 10 if <condition>

example:

a = 10 if true # a = 10
b = 10 if false # b = nil
  1. a = 10 unless <condition>

example:

a = 10 unless false # a = 10
b = 10 unless true # b = nil
  1. a = <condition> ? <a> : <b>

example:

a = true ? 10 : 100 # a = 10
a = false ? 10 : 100 # a = 100

I hope it helps.

How to import other Python files?

I'd like to add this note I don't very clearly elsewhere; inside a module/package, when loading from files, the module/package name must be prefixed with the mymodule. Imagine mymodule being layout like this:

/main.py
/mymodule
    /__init__.py
    /somefile.py
    /otherstuff.py

When loading somefile.py/otherstuff.py from __init__.py the contents should look like:

from mymodule.somefile import somefunc
from mymodule.otherstuff import otherfunc

Cannot open include file: 'stdio.h' - Visual Studio Community 2017 - C++ Error

Scenario:

  1. Windows 10 with Visual Studio 2017 (FRESH installation).

  2. 'C' project (ERROR like -> cannot open source file: 'stdio.h', 'windows.h', etc.).

Resolve:

  1. Run 'Visual Studio Installer'.

  2. Click button 'Modify'.

  3. Select 'Desktop development with C++'.

  4. From "Installation details"(usually on the right-sidebar) select:

    4.1. Windows 10 SDK(10.0.17134.0).

    • Version of SDK in 4.1. is just for example.
  5. Click button 'Modify', to apply changes.

  6. Right-click 'SomeProject' -> 'Properties'.
  7. 'Configuration:' -> 'All Configurations' and 'Platform:' -> 'All Platforms'.
  8. 'Configuration Properties' -> 'General' -> 'Windows SDK Version':
    • change(select from combobox) SDK version to currently installed;
  9. Click button 'Apply', to apply changes.

heroku - how to see all the logs

I prefer to do it this way

heroku logs --tail | tee -a herokuLogs

You can leave the script running in background and you can simply filter the logs from the text file the way you want anytime.

C# switch on type

See gjvdkamp's answer below; this feature now exists in C#


I usually use a dictionary of types and delegates.
var @switch = new Dictionary<Type, Action> {
    { typeof(Type1), () => ... },
    { typeof(Type2), () => ... },
    { typeof(Type3), () => ... },
};

@switch[typeof(MyType)]();

It's a little less flexible as you can't fall through cases, continue etc. But I rarely do so anyway.

jQuery function to get all unique elements from an array?

this is js1568's solution, modified to work on a generic array of objects, like:

 var genericObject=[
        {genProp:'this is a string',randomInt:10,isBoolean:false},
        {genProp:'this is another string',randomInt:20,isBoolean:false},
        {genProp:'this is a string',randomInt:10,isBoolean:true},
        {genProp:'this is another string',randomInt:30,isBoolean:false},
        {genProp:'this is a string',randomInt:40,isBoolean:true},
        {genProp:'i like strings',randomInt:60,isBoolean:true},
        {genProp:'this is a string',randomInt:70,isBoolean:true},
        {genProp:'this string is unique',randomInt:50,isBoolean:true},
        {genProp:'this is a string',randomInt:50,isBoolean:false},
        {genProp:'i like strings',randomInt:70,isBoolean:false}
    ]

It accepts one more parameter called propertyName, guess! :)

  $.extend({
        distinctObj:function(obj,propertyName) {
            var result = [];
            $.each(obj,function(i,v){
                var prop=eval("v."+propertyName);
                if ($.inArray(prop, result) == -1) result.push(prop);
            });
            return result;
        }
    });

so, if you need to extract a list of unique values for a given property, for example the values used for randomInt property, use this:

$.distinctObj(genericObject,'genProp');

it returns an array like this:

["this is a string", "this is another string", "i like strings", "this string is unique"] 

How can I keep a container running on Kubernetes?

There are many different ways for accomplishing this, but one of the most elegant one is:

kubectl run -i --tty --image ubuntu:latest ubuntu-test --restart=Never --rm /bin/sh

java.lang.ClassCastException

According to the documentation:

Thrown to indicate that the code has attempted to cast an Object to a subclass of which it is not an instance. For example, the following code generates a ClassCastException:

Object x = new Integer(0);
System.out.println((String)x); 

VBA - If a cell in column A is not blank the column B equals

Another way (Using Formulas in VBA). I guess this is the shortest VBA code as well?

Sub Sample()
    Dim ws As Worksheet
    Dim lRow As Long

    Set ws = ThisWorkbook.Sheets("Sheet1")

    With ws
        lRow = .Range("A" & .Rows.Count).End(xlUp).Row

        .Range("B1:B" & lRow).Formula = "=If(A1<>"""",""My Text"","""")"
        .Range("B1:B" & lRow).Value = .Range("B1:B" & lRow).Value
    End With
End Sub

How to replace all strings to numbers contained in each string in Notepad++?

Replace (.*")\d+(")

With $1x$2

Where x is your "value inside scopes".

Get file name from URL

Here is the simplest way to do it in Android. I know it will not work in Java but It may help Android application developer.

import android.webkit.URLUtil;

public String getFileNameFromURL(String url) {
    String fileNameWithExtension = null;
    String fileNameWithoutExtension = null;
    if (URLUtil.isValidUrl(url)) {
        fileNameWithExtension = URLUtil.guessFileName(url, null, null);
        if (fileNameWithExtension != null && !fileNameWithExtension.isEmpty()) {
            String[] f = fileNameWithExtension.split(".");
            if (f != null & f.length > 1) {
                fileNameWithoutExtension = f[0];
            }
        }
    }
    return fileNameWithoutExtension;
}

Why can a function modify some arguments as perceived by the caller, but not others?

Python is copy by value of reference. An object occupies a field in memory, and a reference is associated with that object, but itself occupies a field in memory. And name/value is associated with a reference. In python function, it always copy the value of the reference, so in your code, n is copied to be a new name, when you assign that, it has a new space in caller stack. But for the list, the name also got copied, but it refer to the same memory(since you never assign the list a new value). That is a magic in python!

"Please try running this command again as Root/Administrator" error when trying to install LESS

This will definitely help. Answer by npm itself. https://docs.npmjs.com/getting-started/fixing-npm-permissions

Below is extracted from the URL for your convenience.


Option 1: Change the permission to npm's default directory

  1. Find the path to npm's directory:

    npm config get prefix

For many systems, this will be /usr/local.

WARNING: If the displayed path is just /usr, switch to Option 2 or you will mess up your permissions.

  1. Change the owner of npm's directories to the name of the current user (your username!):

    sudo chown -R $(whoami) $(npm config get prefix)/{lib/node_modules,bin,share}

This changes the permissions of the sub-folders used by npm and some other tools (lib/node_modules, bin, and share).


Option 2: Change npm's default directory to another directory

  1. Make a directory for global installations:

    mkdir ~/.npm-global

  2. Configure npm to use the new directory path:

    npm config set prefix '~/.npm-global'

  3. Open or create a ~/.profile file and add this line:

    export PATH=~/.npm-global/bin:$PATH

  4. Back on the command line, update your system variables:

    source ~/.profile

Test: Download a package globally without using sudo.

`npm install -g jshint`

Instead of steps 2-4, you can use the corresponding ENV variable (e.g. if you don't want to modify ~/.profile):

NPM_CONFIG_PREFIX=~/.npm-global


Option 3: Use a package manager that takes care of this for you

If you're doing a fresh install of Node on Mac OS, you can avoid this problem altogether by using the Homebrew package manager. Homebrew sets things up out of the box with the correct permissions.

brew install node

Keyboard shortcut to comment lines in Sublime Text 2

Ctrl+d and Ctrl+Shift+d....

[

{ "keys": ["ctrl+d"], "command": "toggle_comment", "args": { "block": false } },

{ "keys": ["ctrl+shift+d"], "command": "toggle_comment", "args": { "block": true } },

]

Split and join C# string

Well, here is my "answer". It uses the fact that String.Split can be told hold many items it should split to (which I found lacking in the other answers):

string theString = "Some Very Large String Here";
var array = theString.Split(new [] { ' ' }, 2); // return at most 2 parts
// note: be sure to check it's not an empty array
string firstElem = array[0];
// note: be sure to check length first
string restOfArray = array[1];

This is very similar to the Substring method, just by a different means.

How to format a floating number to fixed width in Python

I needed something similar for arrays. That helped me

some_array_rounded=np.around(some_array, 5)

How to get json key and value in javascript?

http://jsfiddle.net/v8aWF/

Worked out a fiddle. Do check it out

(function() {
    var oJson = {
        "name": "", 
        "skills": "", 
        "jobtitle": "Entwickler", 
        "res_linkedin": "GwebSearch"
    }
    alert(oJson.jobtitle);
})();

How do I use modulus for float/double?

I thought the regular modulus operator would work for this in java, but it can't be hard to code. Just divide the numerator by the denominator, and take the integer portion of the result. Multiply that by the denominator, and subtract the result from the numerator.

x = n / d
xint = Integer portion of x
result = n - d * xint

Angular Material: mat-select not selecting default

Use a binding for the value in your template.

value="{{ option.id }}"

should be

[value]="option.id"

And in your selected value use ngModel instead of value.

<mat-select [(value)]="selected2">

should be

<mat-select [(ngModel)]="selected2">

Complete code:

<div>
  <mat-select [(ngModel)]="selected2">
    <mat-option *ngFor="let option of options2" [value]="option.id">{{ option.name }}</mat-option>
  </mat-select>
</div>

On a side note as of version 2.0.0-beta.12 the material select now accepts a mat-form-field element as the parent element so it is consistent with the other material input controls. Replace the div element with mat-form-field element after you upgrade.

<mat-form-field>
  <mat-select [(ngModel)]="selected2">
    <mat-option *ngFor="let option of options2" [value]="option.id">{{ option.name }}</mat-option>
  </mat-select>
</mat-form-field>

Adding delay between execution of two following lines

If you're targeting iOS 4.0+, you can do the following:

[executing first operation];
double delayInSeconds = 2.0;
dispatch_time_t popTime = dispatch_time(DISPATCH_TIME_NOW, (int64_t)(delayInSeconds * NSEC_PER_SEC));
dispatch_after(popTime, dispatch_get_main_queue(), ^(void){
    [executing second operation];
});

How to find all trigger associated with a table with SQL Server?

You can do this simply with SSMS. Just go to your table name and expand the Triggers node to view a list of triggers associated with that table. Right click to modify your trigger. enter image description here

Parsing time string in Python

Your best bet is to have a look at strptime()

Something along the lines of

>>> from datetime import datetime
>>> date_str = 'Tue May 08 15:14:45 +0800 2012'
>>> date = datetime.strptime(date_str, '%a %B %d %H:%M:%S +0800 %Y')
>>> date
datetime.datetime(2012, 5, 8, 15, 14, 45)

Im not sure how to do the +0800 timezone unfortunately, maybe someone else can help out with that.

The formatting strings can be found at http://docs.python.org/library/time.html#time.strftime and are the same for formatting the string for printing.

Hope that helps

Mark

PS, Your best bet for timezones in installing pytz from pypi. ( http://pytz.sourceforge.net/ ) in fact I think pytz has a great datetime parsing method if i remember correctly. The standard lib is a little thin on the ground with timezone functionality.

Get folder up one level

The parent directory of an included file would be

dirname(getcwd())

e.g. the file is /var/www/html/folder/inc/file.inc.php which is included in /var/www/html/folder/index.php

then by calling /file/index.php

getcwd() is /var/www/html/folder  
__DIR__ is /var/www/html/folder/inc  
so dirname(__DIR__) is /var/www/html/folder

but what we want is /var/www/html which is dirname(getcwd())

Python: fastest way to create a list of n lists

The list comprehensions actually are implemented more efficiently than explicit looping (see the dis output for example functions) and the map way has to invoke an ophaque callable object on every iteration, which incurs considerable overhead overhead.

Regardless, [[] for _dummy in xrange(n)] is the right way to do it and none of the tiny (if existent at all) speed differences between various other ways should matter. Unless of course you spend most of your time doing this - but in that case, you should work on your algorithms instead. How often do you create these lists?

How to check if an item is selected from an HTML drop down list?

Well you missed quotation mark around your string selectcard it should be "selectcard"

if (card.value == selectcard)

should be

if (card.value == "selectcard")

Here is complete code for that

function validate()
{
 var ddl = document.getElementById("cardtype");
 var selectedValue = ddl.options[ddl.selectedIndex].value;
    if (selectedValue == "selectcard")
   {
    alert("Please select a card type");
   }
}

JS Fiddle Demo

Assigning the output of a command to a variable

Try:

output=$(ps -ef | awk '/siebsvc –s siebsrvr/ && !/awk/ { a++ } END { print a }'); echo $output

Wrapping your command in $( ) tells the shell to run that command, instead of attempting to set the command itself to the variable named "output". (Note that you could also use backticks `command`.)

I can highly recommend http://tldp.org/LDP/abs/html/commandsub.html to learn more about command substitution.

Also, as 1_CR correctly points out in a comment, the extra space between the equals sign and the assignment is causing it to fail. Here is a simple example on my machine of the behavior you are experiencing:

jed@MBP:~$ foo=$(ps -ef |head -1);echo $foo
UID PID PPID C STIME TTY TIME CMD

jed@MBP:~$ foo= $(ps -ef |head -1);echo $foo
-bash: UID: command not found
UID PID PPID C STIME TTY TIME CMD

How do I calculate square root in Python?

What you're seeing is integer division. To get floating point division by default,

from __future__ import division

Or, you could convert 1 or 2 of 1/2 into a floating point value.

sqrt = x**(1.0/2)

"Uncaught TypeError: a.indexOf is not a function" error when opening new foundation project

This error might be caused by the jQuery event-aliases like .load(), .unload() or .error() that all are deprecated since jQuery 1.8. Lookup for these aliases in your code and replace them with the .on() method instead. For example, replace the following deprecated excerpt:

$(window).load(function(){...});

with the following:

$(window).on('load', function(){ ...});

JavaScript: How to pass object by value?

If you are using lodash or npm, use lodash's merge function to deep copy all of the object's properties to a new empty object like so:

var objectCopy = lodash.merge({}, originalObject);

https://lodash.com/docs#merge

https://www.npmjs.com/package/lodash.merge

How to run server written in js with Node.js

Just try

node server

from cmd prompt in that directory

Browser/HTML Force download of image from src="data:image/jpeg;base64..."

I guess an img tag is needed as a child of an a tag, the following way:

<a download="YourFileName.jpeg" href="data:image/jpeg;base64,iVBO...CYII=">
    <img src="data:image/jpeg;base64,iVBO...CYII="></img>
</a>

or

<a download="YourFileName.jpeg" href="/path/to/OtherFile.jpg">
    <img src="/path/to/OtherFile.jpg"></img>
</a>

Only using the a tag as explained in #15 didn't worked for me with the latest version of Firefox and Chrome, but putting the same image data in both a.href and img.src tags worked for me.

From JavaScript it could be generated like this:

var data = canvas.toDataURL("image/jpeg");

var img = document.createElement('img');
img.src = data;

var a = document.createElement('a');
a.setAttribute("download", "YourFileName.jpeg");
a.setAttribute("href", data);
a.appendChild(img);

var w = open();
w.document.title = 'Export Image';
w.document.body.innerHTML = 'Left-click on the image to save it.';
w.document.body.appendChild(a);

How to resolve "git did not exit cleanly (exit code 128)" error on TortoiseGit?

for me I simply had to add configure my git username and email with the following commands:

git config --global user.email "[email protected]"
git config --global user.name "Your Name"

docker error: /var/run/docker.sock: no such file or directory

If you're using CentOS 7, and you've installed Docker via yum, don't forget to run:

$ sudo systemctl start docker
$ sudo systemctl enable docker

This will start the server, as well as re-start it automatically on boot.

pull access denied repository does not exist or may require docker login

The message usually comes when you put the wrong image name. Please check your image if it exists on the Docker repository with the correct tag. It helped me.

docker run -d -p 80:80 --name ngnix ngnix:latest
Unable to find image 'ngnix:latest' locally
docker: Error response from daemon: pull access denied for ngnix, repository does not exist or may require 'docker login': denied: requested access to the resource is denied.
See 'docker run --help'.
$ docker run -d -p 80:80 --name nginx nginx:latest
Unable to find image 'nginx:latest' locally
latest: Pulling from library/nginx

How can I make a CSS table fit the screen width?

Set font-size in viewport-width-related units, e.g.:

table { font-size: 0.9vw; }

This will make font unreadable when page is too narrow, but sometimes this is acceptable.

How do I parse command line arguments in Bash?

I give you The Function parse_params that will parse params from the command line.

  1. It is a pure Bash solution, no additional utilities.
  2. Does not pollute global scope.
  3. Effortlessly returns you simple to use variables, that you could build further logic on.
  4. Amount of dashes before params does not matter (--all equals -all equals all=all)

The script below is a copy-paste working demonstration. See show_use function to understand how to use parse_params.

Limitations:

  1. Does not support space delimited params (-d 1)
  2. Param names will lose dashes so --any-param and -anyparam are equivalent
  3. eval $(parse_params "$@") must be used inside bash function (it will not work in the global scope)

#!/bin/bash

# Universal Bash parameter parsing
# Parse equal sign separated params into named local variables
# Standalone named parameter value will equal its param name (--force creates variable $force=="force")
# Parses multi-valued named params into an array (--path=path1 --path=path2 creates ${path[*]} array)
# Puts un-named params as-is into ${ARGV[*]} array
# Additionally puts all named params as-is into ${ARGN[*]} array
# Additionally puts all standalone "option" params as-is into ${ARGO[*]} array
# @author Oleksii Chekulaiev
# @version v1.4.1 (Jul-27-2018)
parse_params ()
{
    local existing_named
    local ARGV=() # un-named params
    local ARGN=() # named params
    local ARGO=() # options (--params)
    echo "local ARGV=(); local ARGN=(); local ARGO=();"
    while [[ "$1" != "" ]]; do
        # Escape asterisk to prevent bash asterisk expansion, and quotes to prevent string breakage
        _escaped=${1/\*/\'\"*\"\'}
        _escaped=${_escaped//\'/\\\'}
        _escaped=${_escaped//\"/\\\"}
        # If equals delimited named parameter
        nonspace="[^[:space:]]"
        if [[ "$1" =~ ^${nonspace}${nonspace}*=..* ]]; then
            # Add to named parameters array
            echo "ARGN+=('$_escaped');"
            # key is part before first =
            local _key=$(echo "$1" | cut -d = -f 1)
            # Just add as non-named when key is empty or contains space
            if [[ "$_key" == "" || "$_key" =~ " " ]]; then
                echo "ARGV+=('$_escaped');"
                shift
                continue
            fi
            # val is everything after key and = (protect from param==value error)
            local _val="${1/$_key=}"
            # remove dashes from key name
            _key=${_key//\-}
            # skip when key is empty
            # search for existing parameter name
            if (echo "$existing_named" | grep "\b$_key\b" >/dev/null); then
                # if name already exists then it's a multi-value named parameter
                # re-declare it as an array if needed
                if ! (declare -p _key 2> /dev/null | grep -q 'declare \-a'); then
                    echo "$_key=(\"\$$_key\");"
                fi
                # append new value
                echo "$_key+=('$_val');"
            else
                # single-value named parameter
                echo "local $_key='$_val';"
                existing_named=" $_key"
            fi
        # If standalone named parameter
        elif [[ "$1" =~ ^\-${nonspace}+ ]]; then
            # remove dashes
            local _key=${1//\-}
            # Just add as non-named when key is empty or contains space
            if [[ "$_key" == "" || "$_key" =~ " " ]]; then
                echo "ARGV+=('$_escaped');"
                shift
                continue
            fi
            # Add to options array
            echo "ARGO+=('$_escaped');"
            echo "local $_key=\"$_key\";"
        # non-named parameter
        else
            # Escape asterisk to prevent bash asterisk expansion
            _escaped=${1/\*/\'\"*\"\'}
            echo "ARGV+=('$_escaped');"
        fi
        shift
    done
}

#--------------------------- DEMO OF THE USAGE -------------------------------

show_use ()
{
    eval $(parse_params "$@")
    # --
    echo "${ARGV[0]}" # print first unnamed param
    echo "${ARGV[1]}" # print second unnamed param
    echo "${ARGN[0]}" # print first named param
    echo "${ARG0[0]}" # print first option param (--force)
    echo "$anyparam"  # print --anyparam value
    echo "$k"         # print k=5 value
    echo "${multivalue[0]}" # print first value of multi-value
    echo "${multivalue[1]}" # print second value of multi-value
    [[ "$force" == "force" ]] && echo "\$force is set so let the force be with you"
}

show_use "param 1" --anyparam="my value" param2 k=5 --force --multi-value=test1 --multi-value=test2

Difference between Method and Function?

In C#, they are interchangeable (although method is the proper term) because you cannot write a method without incorporating it into a class. If it were independent of a class, then it would be a function. Methods are functions that operate through a designated class.

align right in a table cell with CSS

What worked for me now is:

CSS:

.right {
  text-align: right;
  margin-right: 1em;
}

.left {
  text-align: left;
  margin-left: 1em;
}

HTML:

<table width="100%">
  <tbody>
    <tr>
      <td class="left">
        <input id="abort" type="submit" name="abort" value="Back">
        <input id="save" type="submit" name="save" value="Save">
      </td>
      <td class="right">
        <input id="delegate" type="submit" name="delegate" value="Delegate">
        <input id="unassign" type="submit" name="unassign" value="Unassign">
        <input id="complete" type="submit" name="complete" value="Complete">
      </td>
    </tr>
  </tbody>
</table>

See the following fiddle:

http://jsfiddle.net/Joysn/3u3SD/

C# switch statement limitations - why?

I suppose there is no fundamental reason why the compiler couldn't automatically translate your switch statement into:

if (t == typeof(int))
{
...
}
elseif (t == typeof(string))
{
...
}
...

But there isn't much gained by that.

A case statement on integral types allows the compiler to make a number of optimizations:

  1. There is no duplication (unless you duplicate case labels, which the compiler detects). In your example t could match multiple types due to inheritance. Should the first match be executed? All of them?

  2. The compiler can choose to implement a switch statement over an integral type by a jump table to avoid all the comparisons. If you are switching on an enumeration that has integer values 0 to 100 then it creates an array with 100 pointers in it, one for each switch statement. At runtime it simply looks up the address from the array based on the integer value being switched on. This makes for much better runtime performance than performing 100 comparisons.

What is the difference between Integer and int in Java?

int is a primitive type that represent an integer. whereas Integer is an Object that wraps int. The Integer object gives you more functionality, such as converting to hex, string, etc.

You can also use OOP concepts with Integer. For example, you can use Integer for generics (i.e. Collection<Integer>).

How to get the selected item from ListView?

By default, when you click on a ListView item it doesn't change its state to "selected". So, when the event fires and you do:

myList.getSelectedItem();

The method doesn't have anything to return. What you have to do is to use the position and obtain the underlying object by doing:

myList.getItemAtPosition(position);

Python wildcard search in string

Do you mean any specific syntax for wildcards? Usually * stands for "one or many" characters and ? stands for one.

The simplest way probably is to translate a wildcard expression into a regular expression, then use that for filtering the results.

Nested jQuery.each() - continue/break

Labeled Break

outerloop:
$(sentences).each(function() 
{
    $(words).each(function(i) 
    {
        break; /* breaks inner loop */
    } 
    $(words).each(function(i)  
    {
        break outerloop; /* breaks outer loop */
    }
}

Configure Nginx with proxy_pass

Give this a try...

server {
    listen   80;
    server_name  dev.int.com;
    access_log off;
    location / {
        proxy_pass http://IP:8080;
        proxy_set_header    Host            $host;
        proxy_set_header    X-Real-IP       $remote_addr;
        proxy_set_header    X-Forwarded-for $remote_addr;
        port_in_redirect off;
        proxy_redirect   http://IP:8080/jira  /;
        proxy_connect_timeout 300;
    }

    location ~ ^/stash {
        proxy_pass http://IP:7990;
        proxy_set_header    Host            $host;
        proxy_set_header    X-Real-IP       $remote_addr;
        proxy_set_header    X-Forwarded-for $remote_addr;
        port_in_redirect off;
        proxy_redirect   http://IP:7990/  /stash;
        proxy_connect_timeout 300;
    }

    error_page   500 502 503 504  /50x.html;
    location = /50x.html {
        root   /usr/local/nginx/html;
    }
}

How do I convert an interval into a number of hours with postgres?

If you convert table field:

  1. Define the field so it contains seconds:

     CREATE TABLE IF NOT EXISTS test (
         ...
         field        INTERVAL SECOND(0)
     );
    
  2. Extract the value. Remember to cast to int other wise you can get an unpleasant surprise once the intervals are big:

    EXTRACT(EPOCH FROM field)::int

No connection could be made because the target machine actively refused it?

Well, I've received this error today on Windows 8 64-bit out of the blue, for the first time, and it turns out my my.ini had been reset, and the bin/mysqld file had been deleted, among other items in the "Program Files/MySQL/MySQL Server 5.6" folder.

To fix it, I had to run the MySQL installer again, installing only the server, and copy a recent version of the my.ini file from "ProgramData/MySQL/MySQL Server 5.6", named my_2014-03-28T15-51-20.ini in my case (don't know how or why that got copied there so recently) back into "Program Files/MySQL/MySQL Server 5.6".

The only change to the system since MySQL worked was the installation of Native Instruments' Traktor 2 and a Traktor Audio 2 sound card, which really shouldn't have caused this problem, and no one else has used the system besides me. If anyone has a clue, it would be kind of you to comment to prevent this for me and anyone else who has encountered this.

CORS jQuery AJAX request

It's easy, you should set server http response header first. The problem is not with your front-end javascript code. You need to return this header:

Access-Control-Allow-Origin:*

or

Access-Control-Allow-Origin:your domain

In Apache config files, the code is like this:

Header set Access-Control-Allow-Origin "*"

In nodejs,the code is like this:

res.setHeader('Access-Control-Allow-Origin','*');

How can I create a table with borders in Android?

Here is a great way to solve this problem:

Create a rectangle drawable with rounded corners like this:

<?xml version="1.0" encoding="utf-8"?>
<shape xmlns:android="http://schemas.android.com/apk/res/android" android:shape="rectangle"> 
    <stroke android:width="2dp"
            android:color="#888888"/> 

    <corners android:bottomRightRadius="6dp" 
             android:bottomLeftRadius="6dp" 
             android:topLeftRadius="6dp" 
             android:topRightRadius="6dp"/> 
</shape>

save it in the drawable folder with the name rounded_border.xml

Then create a relative layout that uses the rounded_border as a background like this:

<?xml version="1.0" encoding="utf-8"?>
<RelativeLayout xmlns:android="http://schemas.android.com/apk/res/android"
    android:layout_width="match_parent"
    android:layout_height="match_parent" 
    android:background="@drawable/rounded_border">
   <ListView 
       android:id="@+id/list_view"
       android:layout_width="match_parent"
       android:layout_height="wrap_content"/>

</RelativeLayout>

save that in your layout folder and name it table_with_border.xml

then whenever you need such a table pull it into a view using the include syntax like this:

<include
        android:id="@+id/rounded_table"
        android:layout_width="match_parent"
        android:layout_height="wrap_content"
        layout="@layout/table_with_border" />

You will probably want to add some spacing around the edges - so just wrap the include in a LinearLayout and add some padding around the edges.

Simple and easy way to get a pretty border around a table.

Example of a strong and weak entity types

After browsing search engines for a few hours I came across a site with a great ERD example here: http://www.exploredatabase.com/2016/07/description-about-weak-entity-sets-in-DBMS.html

I've recreated the ERD. Unfortunately they did not specify the primary key of the weak entity.

enter image description here

If the building could only have one and only one apartment, then it seems the partial discriminator room number would not be created (i.e. discarded).

Extract code country from phone number [libphonenumber]

In here you can save the phone number as international formatted phone number

internationalFormatPhoneNumber = phoneUtil.format(givenPhoneNumber, PhoneNumberFormat.INTERNATIONAL);

it return the phone number as International format +94 71 560 4888

so now I have get country code as this

String countryCode = internationalFormatPhoneNumber.substring(0,internationalFormatPhoneNumber.indexOf('')).replace('+', ' ').trim();

Hope this will help you

How to convert BigInteger to String in java

You want to use BigInteger.toByteArray()

String msg = "Hello there!";
BigInteger bi = new BigInteger(msg.getBytes());
System.out.println(new String(bi.toByteArray())); // prints "Hello there!"

The way I understand it is that you're doing the following transformations:

  String  -----------------> byte[] ------------------> BigInteger
          String.getBytes()         BigInteger(byte[])

And you want the reverse:

  BigInteger ------------------------> byte[] ------------------> String
             BigInteger.toByteArray()          String(byte[])

Note that you probably want to use overloads of String.getBytes() and String(byte[]) that specifies an explicit encoding, otherwise you may run into encoding issues.

Vue.js: Conditional class style binding

the problem is blade, try this

<i class="fa" v-bind:class="['{{content['cravings']}}' ? 'fa-checkbox-marked' : 'fa-checkbox-blank-outline']"></i>

Grep for beginning and end of line?

are you parsing output of ls -l?

If you are, and you just want to get the file name

find . -iname "*[0-9]" 

If you have no choice because usrLog.txt is created by something/someone else and you absolutely must use this file, other options include

awk '/^[-d].*[0-9]$/' file

Ruby(1.9+)

ruby -ne 'print if /^[-d].*[0-9]$/' file

Bash

while read -r line ; do  case $line in [-d]*[0-9] ) echo $line;  esac; done < file

Beginner Python: AttributeError: 'list' object has no attribute

They are lists because you type them as lists in the dictionary:

bikes = {
    # Bike designed for children"
    "Trike": ["Trike", 20, 100],
    # Bike designed for everyone"
    "Kruzer": ["Kruzer", 50, 165]
    }

You should use the bike-class instead:

bikes = {
    # Bike designed for children"
    "Trike": Bike("Trike", 20, 100),
    # Bike designed for everyone"
    "Kruzer": Bike("Kruzer", 50, 165)
    }

This will allow you to get the cost of the bikes with bike.cost as you were trying to.

for bike in bikes.values():
    profit = bike.cost * margin
    print(bike.name + " : " + str(profit))

This will now print:

Kruzer : 33.0
Trike : 20.0

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.

How to use jQuery to select a dropdown option?

I would do it this way

 $("#idElement").val('optionValue').trigger('change');

ADB Driver and Windows 8.1

In Windows 7, 8 or 8.1, in Devices Manager:

  1. Select tree 'Android Device': remove 'Android Composite ADB Interface' [?]
  2. Press on main root of devices tree and call context menu (by right mouse click) and click on 'Update configuration'
  3. After updating your device should appear in 'Other devices'
  4. Select your device, call context menu from it and choose 'Update driver' and perform this updating

Python: list of lists

When you run the code

listoflists.append((list, list[0]))

You are not (as I think you expect) adding a copy of list to the end of listoflists. What you are doing is adding a reference to list to the end of listoflists. Thus, every time you update list, it updates every reference to list, which in this case, is every item in listoflists

What you could do instead is something like this:

listoflists = []
for i in range(1, 10):
    listoflists.append((range(i), 0))

Is there a way to get a list of column names in sqlite?

You can get a list of column names by running:

SELECT name FROM PRAGMA_TABLE_INFO('your_table');
name      
tbl_name  
rootpage  
sql

You can check if a certain column exists by running:

SELECT 1 FROM PRAGMA_TABLE_INFO('your_table') WHERE name='sql';
1

Reference:

https://www.sqlite.org/pragma.html#pragfunc

How to detect the physical connected state of a network cable/connector?

On the low level, these events can be caught using rtnetlink sockets, without any polling. Side note: if you use rtnetlink, you have to work together with udev, or your program may get confused when udev renames a new network interface.

The problem with doing network configurations with shell scripts is that shell scripts are terrible for event handling (such as a network cable being plugged in and out). If you need something more powerful, take a look at my NCD programming language, a programming language designed for network configurations.

For example, a simple NCD script that will print "cable in" and "cable out" to stdout (assuming the interface is already up):

process foo {
    # Wait for device to appear and be configured by udev.
    net.backend.waitdevice("eth0");
    # Wait for cable to be plugged in.
    net.backend.waitlink("eth0");
    # Print "cable in" when we reach this point, and "cable out"
    # when we regress.
    println("cable in");   # or pop_bubble("Network cable in.");
    rprintln("cable out"); # or rpop_bubble("Network cable out!");
                           # just joking, there's no pop_bubble() in NCD yet :)
}

(internally, net.backend.waitlink() uses rtnetlink, and net.backend.waitdevice() uses udev)

The idea of NCD is that you use it exclusively to configure the network, so normally, configuration commands would come in between, such as:

process foo {
    # Wait for device to appear and be configured by udev.
    net.backend.waitdevice("eth0");
    # Set device up.
    net.up("eth0");
    # Wait for cable to be plugged in.
    net.backend.waitlink("eth0");
    # Add IP address to device.
    net.ipv4.addr("eth0", "192.168.1.61", "24");
}

The important part to note is that execution is allowed to regress; in the second example, for instance, if the cable is pulled out, the IP address will automatically be removed.

How can I list all the deleted files in a Git repository?

Citing this Stack Overflow answer.

It is a pretty neat way to get type-of-change (A:Added, M:Modified, D:Deleted) for each file that got changed.

git diff --name-status

List All Google Map Marker Images

var pinIcon = new google.maps.MarkerImage(
    "http://chart.apis.google.com/chart?chst=d_map_pin_letter&chld=%E2%80%A2|00D900",
    null, /* size is determined at runtime */
    null, /* origin is 0,0 */
    null, /* anchor is bottom center of the scaled image */
    new google.maps.Size(12, 18)
);

How to add a custom right-click menu to a webpage?

<html>
<head>
<style>
.rightclick {
    /* YOUR CONTEXTMENU'S CSS */
    visibility: hidden;
    background-color: white;
    border: 1px solid grey;
    width: 200px;
    height: 300px;
}
</style>
</head>
<body>
  <div class="rightclick" id="ya">
    <p onclick="alert('choc-a-late')">I like chocolate</p><br><p onclick="awe-so-me">I AM AWESOME</p>
  </div>
  <p>Right click to get sweet results!</p>
</body>
<script>
    document.onclick = noClick;
    document.oncontextmenu = rightClick;
    function rightClick(e) {
        e = e || window.event;
        e.preventDefault();
        document.getElementById("ya").style.visibility = "visible";
        console.log("Context Menu v1.3.0 by IamGuest opened.");
   }
function noClick() {
    document.getElementById("ya").style.visibility = "hidden";
    console.log("Context Menu v1.3.0 by IamGuest closed.");
}
</script>
<!-- Coded by IamGuest. Thank you for using this code! -->
</html>

You can tweak and modify this code to make a better looking, more efficient contextmenu. As for modifying an existing contextmenu, I'm not sure how to do that... Check out this fiddle for an organized point of view. Also, try clicking the items in my contextmenu. They should alert you a few awesome messages. If they don't work, try something more... complex.

What does servletcontext.getRealPath("/") mean and when should I use it

There is also a change between Java 7 and Java 8. Admittedly it involves the a deprecated call, but I had to add a "/" to get our program working! Here is the link discussing it Why does servletContext.getRealPath returns null on tomcat 8?

Correct path for img on React.js

  1. Make an images folder inside src(/src/images) And keep your image in it. Then import this image in your component(use your relative path). Like below-

    import imageSrc from './images/image-name.jpg';

    And then in your component.

    <img title="my-img" src={imageSrc} alt="my-img" />

  2. Another way is to keep images in public folder and import them using relative path. For this make an image folder in public folder and keep your image in it. And then in your component use it like below.

    <img title="my-img" src='/images/my-image.jpg' alt="my-img" />

    Both method work but first one is recommended because its cleaner way and images are handled by webpack during build time.

How to get an object's property's value by property name?

Here is an alternative way to get an object's property value:

write-host $(get-something).SomeProp

How to reset index in a pandas dataframe?

DataFrame.reset_index is what you're looking for. If you don't want it saved as a column, then do:

df = df.reset_index(drop=True)

If you don't want to reassign:

df.reset_index(drop=True, inplace=True)

Convert InputStream to byte array in Java

I use this.

public static byte[] toByteArray(InputStream is) throws IOException {
        ByteArrayOutputStream output = new ByteArrayOutputStream();
        try {
            byte[] b = new byte[4096];
            int n = 0;
            while ((n = is.read(b)) != -1) {
                output.write(b, 0, n);
            }
            return output.toByteArray();
        } finally {
            output.close();
        }
    }

Git: Remove committed file after push

Reset the file in a correct state, commit, and push again.

If you're sure nobody else has fetched your changes yet, you can use --amend when committing, to modify your previous commit (i.e. rewrite history), and then push. I think you'll have to use the -f option when pushing, to force the push, though.

Why is NULL undeclared?

NULL isn't a native part of the core C++ language, but it is part of the standard library. You need to include one of the standard header files that include its definition. #include <cstddef> or #include <stddef.h> should be sufficient.

The definition of NULL is guaranteed to be available if you include cstddef or stddef.h. It's not guaranteed, but you are very likely to get its definition included if you include many of the other standard headers instead.

Giving multiple URL patterns to Servlet Filter

If an URL pattern starts with /, then it's relative to the context root. The /Admin/* URL pattern would only match pages on http://localhost:8080/EMS2/Admin/* (assuming that /EMS2 is the context path), but you have them actually on http://localhost:8080/EMS2/faces/Html/Admin/*, so your URL pattern never matches.

You need to prefix your URL patterns with /faces/Html as well like so:

<url-pattern>/faces/Html/Admin/*</url-pattern>

You can alternatively also just reconfigure your web project structure/configuration so that you can get rid of the /faces/Html path in the URLs so that you can just open the page by for example http://localhost:8080/EMS2/Admin/Upload.xhtml.

Your filter mapping syntax is all fine. However, a simpler way to specify multiple URL patterns is to just use only one <filter-mapping> with multiple <url-pattern> entries:

<filter-mapping>
    <filter-name>LoginFilter</filter-name>
    <url-pattern>/faces/Html/Employee/*</url-pattern>
    <url-pattern>/faces/Html/Admin/*</url-pattern>
    <url-pattern>/faces/Html/Supervisor/*</url-pattern>
</filter-mapping>

Alter a SQL server function to accept new optional parameter

From CREATE FUNCTION:

When a parameter of the function has a default value, the keyword DEFAULT must be specified when the function is called to retrieve the default value. This behavior is different from using parameters with default values in stored procedures in which omitting the parameter also implies the default value.

So you need to do:

SELECT dbo.fCalculateEstimateDate(647,DEFAULT)

Improving bulk insert performance in Entity framework

Maybe this answer here will help you. Seems that you want to dispose of the context periodically. This is because the context gets bigger and bigger as the attached entities grows.

How to exit a function in bash

If you want to return from an outer function with an error without exiting you can use this trick:

do-something-complex() {
  # Using `return` here would only return from `fail`, not from `do-something-complex`.
  # Using `exit` would close the entire shell.
  # So we (ab)use a different feature. :)
  fail() { : "${__fail_fast:?$1}"; }

  nested-func() {
      try-this || fail "This didn't work"
      try-that || fail "That didn't work"
  }
  nested-func
}

Trying it out:

$ do-something-complex
try-this: command not found
bash: __fail_fast: This didn't work

This has the added benefit/drawback that you can optionally turn off this feature: __fail_fast=x do-something-complex.

Note that this causes the outermost function to return 1.

Scrollbar without fixed height/Dynamic height with scrollbar

 <div id="scroll">
    <p>Try to add more text</p>
 </div>

here's the css code

#scroll {
   overflow-y:auto;
   height:auto;
   max-height:200px;
   border:1px solid black;
   width:300px;
 }

here's the demo JSFIDDLE

Windows could not start the SQL Server (MSSQLSERVER) on Local Computer... (error code 3417)

Check if you did compress the driver or folder in where you put the .mdf file.

If so, plesae goto the driver or folder, change the compress option by

Properties -> Advanced and unticked the “Compress contents to save disk space” checkbox.

After above things, you should be able to start the service again.

How to properly use the "choices" field option in Django

I think no one actually has answered to the first question:

Why did they create those variables?

Those variables aren't strictly necessary. It's true. You can perfectly do something like this:

MONTH_CHOICES = (
    ("JANUARY", "January"),
    ("FEBRUARY", "February"),
    ("MARCH", "March"),
    # ....
    ("DECEMBER", "December"),
)

month = models.CharField(max_length=9,
                  choices=MONTH_CHOICES,
                  default="JANUARY")

Why using variables is better? Error prevention and logic separation.

JAN = "JANUARY"
FEB = "FEBRUARY"
MAR = "MAR"
# (...)

MONTH_CHOICES = (
    (JAN, "January"),
    (FEB, "February"),
    (MAR, "March"),
    # ....
    (DEC, "December"),
)

Now, imagine you have a view where you create a new Model instance. Instead of doing this:

new_instance = MyModel(month='JANUARY')

You'll do this:

new_instance = MyModel(month=MyModel.JAN)

In the first option you are hardcoding the value. If there is a set of values you can input, you should limit those options when coding. Also, if you eventually need to change the code at the Model layer, now you don't need to make any change in the Views layer.

How to finish current activity in Android

I tried using this example but it failed miserably. Every time I use to invoke finish()/ finishactivity() inside a handler, I end up with this menacing java.lang.IllegalAccess Exception. i'm not sure how did it work for the one who posed the question.

Instead the solution I found was that create a method in your activity such as

void kill_activity()
{ 
    finish();
}

Invoke this method from inside the run method of the handler. This worked like a charm for me. Hope this helps anyone struggling with "how to close an activity from a different thread?".

Using variables inside strings

In C# 6 you can use string interpolation:

string name = "John";
string result = $"Hello {name}";

The syntax highlighting for this in Visual Studio makes it highly readable and all of the tokens are checked.

Send JavaScript variable to PHP variable

PHP runs on the server and Javascript runs on the client, so you can't set a PHP variable to equal a Javascript variable without sending the value to the server. You can, however, set a Javascript variable to equal a PHP variable:

<script type="text/javascript">
  var foo = '<?php echo $foo ?>';
</script>

To send a Javascript value to PHP you'd need to use AJAX. With jQuery, it would look something like this (most basic example possible):

var variableToSend = 'foo';
$.post('file.php', {variable: variableToSend});

On your server, you would need to receive the variable sent in the post:

$variable = $_POST['variable'];

fatal error LNK1169: one or more multiply defined symbols found in game programming

The two int variables are defined in the header file. This means that every source file which includes the header will contain their definition (header inclusion is purely textual). The of course leads to multiple definition errors.

You have several options to fix this.

  1. Make the variables static (static int WIDTH = 1024;). They will still exist in each source file, but their definitions will not be visible outside of the source file.

  2. Turn their definitions into declarations by using extern (extern int WIDTH;) and put the definition into one source file: int WIDTH = 1024;.

  3. Probably the best option: make the variables const (const int WIDTH = 1024;). This makes them static implicitly, and also allows them to be used as compile-time constants, allowing the compiler to use their value directly instead of issuing code to read it from the variable etc.

Rotating a view in Android

You could create an animation and apply it to your button view. For example:

    // Locate view
    ImageView diskView = (ImageView) findViewById(R.id.imageView3);

    // Create an animation instance
    Animation an = new RotateAnimation(0.0f, 360.0f, pivotX, pivotY);

    // Set the animation's parameters
    an.setDuration(10000);               // duration in ms
    an.setRepeatCount(0);                // -1 = infinite repeated
    an.setRepeatMode(Animation.REVERSE); // reverses each repeat
    an.setFillAfter(true);               // keep rotation after animation

    // Aply animation to image view
    diskView.setAnimation(an);

Download files from SFTP with SSH.NET library

A simple working code to download a file with SSH.NET library is:

using (Stream fileStream = File.Create(@"C:\target\local\path\file.zip"))
{
    sftp.DownloadFile("/source/remote/path/file.zip", fileStream);
}

See also Downloading a directory using SSH.NET SFTP in C#.


To explain, why your code does not work:

The second parameter of SftpClient.DownloadFile is a stream to write a downloaded contents to.

You are passing in a read stream instead of a write stream. And moreover the path you are opening read stream with is a remote path, what cannot work with File class operating on local files only.

Just discard the File.OpenRead line and use a result of previous File.OpenWrite call instead (that you are not using at all now):

Stream file1 = File.OpenWrite(localFileName);

sftp.DownloadFile(file.FullName, file1);

Or even better, use File.Create to discard any previous contents that the local file may have.

I'm not sure if your localFileName is supposed to hold full path, or just file name. So you may need to add a path too, if necessary (combine localFileName with sDir?)

Declare an empty two-dimensional array in Javascript?

If you want to be able access the matrix like so matrix[i][j]

I find it the most convinient to init it in a loop.

var matrix = [],
    cols = 3;

//init the grid matrix
for ( var i = 0; i < cols; i++ ) {
    matrix[i] = []; 
}

this will give you [ [], [], [] ]

so matrix[0][0] matrix[1][0] return undefined and not the error "Uncaught TypeError: Cannot set property '0' of undefined"

Jquery: Find Text and replace

try this,

$('#id1').html($('#id1').html().replace('dogsss','dollsss'));

working sample

How do I properly escape quotes inside HTML attributes?

&quot; is the correct way, the third of your tests:

<option value="&quot;asd">test</option>

You can see this working below, or on jsFiddle.

_x000D_
_x000D_
alert($("option")[0].value);
_x000D_
<script src="https://ajax.googleapis.com/ajax/libs/jquery/2.1.1/jquery.min.js"></script>_x000D_
<select>_x000D_
  <option value="&quot;asd">Test</option>_x000D_
</select>
_x000D_
_x000D_
_x000D_

Alternatively, you can delimit the attribute value with single quotes:

<option value='"asd'>test</option>

How to fix "unable to open stdio.h in Turbo C" error?

Just Re install the turbo C++ from your Computer and install again in the Directory C:\TC\ Folder.

Again The Problem exists ,then change the directory from FILE>>CHANGE DIRECTORY to C:\TC\BIN\

Login failed for user 'DOMAIN\MACHINENAME$'

In my case I had Identity="ApplicationPoolIdentity" for my IIS Application Pool.

After I added IIS APPPOOL\ApplicationName user to SQL Server it works.

Is div inside list allowed?

If I recall correctly, a div inside a li used to be invalid.

@Flower @Superstringcheese Div should semantically define a section of a document, but it has already practically lost this role. Span should however contain text.

How can I output leading zeros in Ruby?

If the maximum number of digits in the counter is known (e.g., n = 3 for counters 1..876), you can do

str = "file_" + i.to_s.rjust(n, "0")

How to center align the cells of a UICollectionView?

Working version of kgaidis's Objective C answer using Swift 3.0:

let flow = UICollectionViewFlowLayout()

func collectionView(_ collectionView: UICollectionView, layout collectionViewLayout: UICollectionViewLayout, insetForSectionAt section: Int) -> UIEdgeInsets {        
    let numberOfItems = collectionView.numberOfItems(inSection: 0)
    let combinedItemWidth:CGFloat = (CGFloat(numberOfItems) * flow.itemSize.width) + ((CGFloat(numberOfItems) - 1) * flow.minimumInteritemSpacing)
    let padding = (collectionView.frame.size.width - combinedItemWidth) / 2

    return UIEdgeInsetsMake(0, padding, 0, padding)
}

How can I pad an int with leading zeros when using cout << operator?

I would use the following function. I don't like sprintf; it doesn't do what I want!!

#define hexchar(x)    ((((x)&0x0F)>9)?((x)+'A'-10):((x)+'0'))
typedef signed long long   Int64;

// Special printf for numbers only
// See formatting information below.
//
//    Print the number "n" in the given "base"
//    using exactly "numDigits".
//    Print +/- if signed flag "isSigned" is TRUE.
//    Use the character specified in "padchar" to pad extra characters.
//
//    Examples:
//    sprintfNum(pszBuffer, 6, 10, 6,  TRUE, ' ',   1234);  -->  " +1234"
//    sprintfNum(pszBuffer, 6, 10, 6, FALSE, '0',   1234);  -->  "001234"
//    sprintfNum(pszBuffer, 6, 16, 6, FALSE, '.', 0x5AA5);  -->  "..5AA5"
void sprintfNum(char *pszBuffer, int size, char base, char numDigits, char isSigned, char padchar, Int64 n)
{
    char *ptr = pszBuffer;

    if (!pszBuffer)
    {
        return;
    }

    char *p, buf[32];
    unsigned long long x;
    unsigned char count;

    // Prepare negative number
    if (isSigned && (n < 0))
    {
        x = -n;
    }
    else
    {
        x = n;
    }

    // Set up small string buffer
    count = (numDigits-1) - (isSigned?1:0);
    p = buf + sizeof (buf);
    *--p = '\0';

    // Force calculation of first digit
    // (to prevent zero from not printing at all!!!)
    *--p = (char)hexchar(x%base);
    x = x / base;

    // Calculate remaining digits
    while(count--)
    {
        if(x != 0)
        {
            // Calculate next digit
            *--p = (char)hexchar(x%base);
            x /= base;
        }
        else
        {
            // No more digits left, pad out to desired length
            *--p = padchar;
        }
    }

    // Apply signed notation if requested
    if (isSigned)
    {
        if (n < 0)
        {
            *--p = '-';
        }
        else if (n > 0)
        {
            *--p = '+';
        }
        else
        {
            *--p = ' ';
        }
    }

    // Print the string right-justified
    count = numDigits;
    while (count--)
    {
        *ptr++ = *p++;
    }
    return;
}

ListBox with ItemTemplate (and ScrollBar!)

ListBox will try to expand in height that is available.. When you set the Height property of ListBox you get a scrollviewer that actually works...

If you wish your ListBox to accodate the height available, you might want to try to regulate the Height from your parent controls.. In a Grid for example, setting the Height to Auto in your RowDefinition might do the trick...

HTH

Eclipse error "ADB server didn't ACK, failed to start daemon"

I had a similar issue. Killing an existing instance of the ADB process from Task Manager did not work for me.

Just few days back, I had tried to install MIPS SDK and ADT-17 earlier and Eclipse gave me the error, and I did not fix that issue.

So, now, when I got this ADB server didn't ACK, failed to start daemon... issue, I executed 'Check for Updates' in the Eclipse Help menu item. There were no updates available, but at least 'ADB server did not ACK' error disappeared.

I hope this might help in a few cases.

File input 'accept' attribute - is it useful?

The accept attribute is incredibly useful. It is a hint to browsers to only show files that are allowed for the current input. While it can typically be overridden by users, it helps narrow down the results for users by default, so they can get exactly what they're looking for without having to sift through a hundred different file types.

Usage

Note: These examples were written based on the current specification and may not actually work in all (or any) browsers. The specification may also change in the future, which could break these examples.

_x000D_
_x000D_
h1 { font-size: 1em; margin:1em 0; }_x000D_
h1 ~ h1 { border-top: 1px solid #ccc; padding-top: 1em; }
_x000D_
<h1>Match all image files (image/*)</h1>_x000D_
<p><label>image/* <input type="file" accept="image/*"></label></p>_x000D_
_x000D_
<h1>Match all video files (video/*)</h1>_x000D_
<p><label>video/* <input type="file" accept="video/*"></label></p>_x000D_
_x000D_
<h1>Match all audio files (audio/*)</h1>_x000D_
<p><label>audio/* <input type="file" accept="audio/*"></label></p>_x000D_
_x000D_
<h1>Match all image files (image/*) and files with the extension ".someext"</h1>_x000D_
<p><label>.someext,image/* <input type="file" accept=".someext,image/*"></label></p>_x000D_
_x000D_
<h1>Match all image files (image/*) and video files (video/*)</h1>_x000D_
<p><label>image/*,video/* <input type="file" accept="image/*,video/*"></label></p>
_x000D_
_x000D_
_x000D_

From the HTML Specification (source)

The accept attribute may be specified to provide user agents with a hint of what file types will be accepted.

If specified, the attribute must consist of a set of comma-separated tokens, each of which must be an ASCII case-insensitive match for one of the following:

The string audio/*

  • Indicates that sound files are accepted.

The string video/*

  • Indicates that video files are accepted.

The string image/*

  • Indicates that image files are accepted.

A valid MIME type with no parameters

  • Indicates that files of the specified type are accepted.

A string whose first character is a U+002E FULL STOP character (.)

  • Indicates that files with the specified file extension are accepted.

How to delete multiple rows in SQL where id = (x to y)

Please try this:

DELETE FROM `table` WHERE id >=163 and id<= 265

What is the behavior of integer division?

Where the result is negative, C truncates towards 0 rather than flooring - I learnt this reading about why Python integer division always floors here: Why Python's Integer Division Floors

How to set environment variable or system property in spring tests?

The right way to do this, starting with Spring 4.1, is to use a @TestPropertySource annotation.

@RunWith(SpringJUnit4ClassRunner.class)
@ContextConfiguration(locations = "classpath:whereever/context.xml")
@TestPropertySource(properties = {"myproperty = foo"})
public class TestWarSpringContext {
    ...    
}

See @TestPropertySource in the Spring docs and Javadocs.

Understanding .get() method in Python

If d is a dictionary, then d.get(k, v) means, give me the value of k in d, unless k isn't there, in which case give me v. It's being used here to get the current count of the character, which should start at 0 if the character hasn't been encountered before.

Append text with .bat

You need to use ECHO. Also, put the quotes around the entire file path if it contains spaces.

One other note, use > to overwrite a file if it exists or create if it does not exist. Use >> to append to an existing file or create if it does not exist.

Overwrite the file with a blank line:

ECHO.>"C:\My folder\Myfile.log"

Append a blank line to a file:

ECHO.>>"C:\My folder\Myfile.log"

Append text to a file:

ECHO Some text>>"C:\My folder\Myfile.log"

Append a variable to a file:

ECHO %MY_VARIABLE%>>"C:\My folder\Myfile.log"

How to take column-slices of dataframe in pandas

Lets use the titanic dataset from the seaborn package as an example

# Load dataset (pip install seaborn)
>> import seaborn.apionly as sns
>> titanic = sns.load_dataset('titanic')

using the column names

>> titanic.loc[:,['sex','age','fare']]

using the column indices

>> titanic.iloc[:,[2,3,6]]

using ix (Older than Pandas <.20 version)

>> titanic.ix[:,[‘sex’,’age’,’fare’]]

or

>> titanic.ix[:,[2,3,6]]

using the reindex method

>> titanic.reindex(columns=['sex','age','fare'])

How to remove padding around buttons in Android?

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

On the Button element, add:

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

Or in your button's style:

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

how to prevent this error : Warning: mysql_fetch_assoc() expects parameter 1 to be resource, boolean given in ... on line 11

You must check if result returned by mysql_query is false.

$r = mysql_qyery("...");
if ($r) {
  mysql_fetch_assoc($r);
}

You can use @mysql_fetch_assoc($r) to avoid error displaying.

JavaScript listener, "keypress" doesn't detect backspace?

Something I wrote up incase anyone comes across an issue with people hitting backspace while thinking they are in a form field

window.addEventListener("keydown", function(e){
    /*
     * keyCode: 8
     * keyIdentifier: "U+0008"
    */
    if(e.keyCode === 8 && document.activeElement !== 'text') {
        e.preventDefault();
        alert('Prevent page from going back');
    }
});

Replace X-axis with own values

Yo could also set labels = FALSE inside axis(...) and print the labels in a separate command with Text. With this option you can rotate the text the text in case you need it

lablist<-as.vector(c(1:10))
axis(1, at=seq(1, 10, by=1), labels = FALSE)
text(seq(1, 10, by=1), par("usr")[3] - 0.2, labels = lablist, srt = 45, pos = 1, xpd = TRUE)

Detailed explanation here

Image with rotated labels

How to setup virtual environment for Python in VS Code?

Have you activated your environment? Also you could try this: vscode select venv

Modifying a file inside a jar

The simplest way I've found to do this in Windows is with WinRAR:

  1. Right-click on the file and choose "Open with WinRAR" from the context menu.
  2. Navigate to the file to be edited and double-click on it to open it in the default editor.
  3. After making the changes, save and exit the editor.
  4. A dialogue will then appear asking if you wish to update the file in the archive - choose "Yes" and the JAR will be updated.

What is the difference between \r and \n?

They're different characters. \r is carriage return, and \n is line feed.

On "old" printers, \r sent the print head back to the start of the line, and \n advanced the paper by one line. Both were therefore necessary to start printing on the next line.

Obviously that's somewhat irrelevant now, although depending on the console you may still be able to use \r to move to the start of the line and overwrite the existing text.

More importantly, Unix tends to use \n as a line separator; Windows tends to use \r\n as a line separator and Macs (up to OS 9) used to use \r as the line separator. (Mac OS X is Unix-y, so uses \n instead; there may be some compatibility situations where \r is used instead though.)

For more information, see the Wikipedia newline article.

EDIT: This is language-sensitive. In C# and Java, for example, \n always means Unicode U+000A, which is defined as line feed. In C and C++ the water is somewhat muddier, as the meaning is platform-specific. See comments for details.

"The certificate chain was issued by an authority that is not trusted" when connecting DB in VM Role from Azure website

If you're using SQL Management Studio, please goto connection properties and click on "Trust server certificated" If you're using SQL Management Studio, please goto connection properties and click on "Trust server certificated"

Required maven dependencies for Apache POI to work

No, you don't have to include all of POI's dependencies. Maven's transitive dependency mechanism will take care of that. As noted you just have to express a dependency on the appropriate POI artifact. For example:

<dependency>
    <groupId>org.apache.poi</groupId>
    <artifactId>poi-ooxml</artifactId>
    <version>3.8-beta4</version>
</dependency>

Edit(UPDATE): I don't know about previous versions but to resolve imports to XSSFWorkbook and other classes in org.apache.poi package you need to add dependency for poi-ooxml too. The dependencies will be:

<dependency>
    <groupId>org.apache.poi</groupId>
    <artifactId>poi</artifactId>
    <version>4.1.2</version>
</dependency>
<dependency>
    <groupId>org.apache.poi</groupId>
    <artifactId>poi-ooxml</artifactId>
    <version>4.1.2</version>
</dependency>

How can I get a user's media from Instagram without authenticating as a user?

One more trick, search photos by hashtags:

GET https://www.instagram.com/graphql/query/?query_hash=3e7706b09c6184d5eafd8b032dbcf487&variables={"tag_name":"nature","first":25,"after":""}

Where:

query_hash - permanent value(i belive its hash of 17888483320059182, can be changed in future)

tag_name - the title speaks for itself

first - amount of items to get (I do not know why, but this value does not work as expected. The actual number of returned photos is slightly larger than the value multiplied by 4.5 (about 110 for the value 25, and about 460 for the value 100))

after - id of the last item if you want to get items from that id. Value of end_cursor from JSON response can be used here.

Add event handler for body.onload by javascript within <body> part

You should really use the following instead (works in all newer browsers):

window.addEventListener('DOMContentLoaded', init, false);

PHP how to get value from array if key is in a variable

Your code seems to be fine, make sure that key you specify really exists in the array or such key has a value in your array eg:

$array = array(4 => 'Hello There');
print_r(array_keys($array));
// or better
print_r($array);

Output:

Array
(
    [0] => 4
)

Now:

$key = 4;
$value = $array[$key];
print $value;

Output:

Hello There

How to divide two columns?

Presumably, those columns are integer columns - which will be the reason as the result of the calculation will be of the same type.

e.g. if you do this:

SELECT 1 / 2

you will get 0, which is obviously not the real answer. So, convert the values to e.g. decimal and do the calculation based on that datatype instead.

e.g.

SELECT CAST(1 AS DECIMAL) / 2

gives 0.500000

Excel VBA Run Time Error '424' object required

Private Sub CommandButton1_Click()

    Workbooks("Textfile_Receiving").Sheets("menu").Range("g1").Value = PROV.Text
    Workbooks("Textfile_Receiving").Sheets("menu").Range("g2").Value = MUN.Text
    Workbooks("Textfile_Receiving").Sheets("menu").Range("g3").Value = CAT.Text
    Workbooks("Textfile_Receiving").Sheets("menu").Range("g4").Value = Label5.Caption

    Me.Hide

    Run "filename"

End Sub

Private Sub MUN_Change()
    Dim r As Integer
    r = 2

    While Range("m" & CStr(r)).Value <> ""
        If Range("m" & CStr(r)).Value = MUN.Text Then
        Label5.Caption = Range("n" & CStr(r)).Value
        End If
        r = r + 1
    Wend

End Sub

Private Sub PROV_Change()
    If PROV.Text = "LAGUNA" Then
        MUN.Text = ""
        MUN.RowSource = "Menu!M26:M56"
    ElseIf PROV.Text = "CAVITE" Then
        MUN.Text = ""
        MUN.RowSource = "Menu!M2:M25"
    ElseIf PROV.Text = "QUEZON" Then
        MUN.Text = ""
        MUN.RowSource = "Menu!M57:M97"
    End If
End Sub

When to use a linked list over an array/array list?

In reality memory locality has a huge performance influence in real processing.

The increased use of disk streaming in "big data" processing vs random access shows how structuring your application around this can dramatically improve performance on a larger scale.

If there is any way to access an array sequentially that is by far the best performing. Designing with this as a goal should be at least considered if performance is important.

Where does Vagrant download its .box files to?

In addition to

Mac:
~/.vagrant.d/

Windows:
C:\Users\%userprofile%\.vagrant.d\boxes

You have to delete the files in VirtualBox/OtherVMprovider to make a clean start.

Read data from SqlDataReader

I have a helper function like:

  public static string GetString(object o)
    {
        if (o == DBNull.Value)
            return "";

        return o.ToString();
    }

then I use it to extract the string:

 tbUserName.Text = GetString(reader["UserName"]);

Set UIButton title UILabel font size programmatically

Check on custom font name whether checkbox on "Target membership" is added. This should help.

psql: server closed the connection unexepectedly

Leaving this here for info,

This error can also be caused if PostgreSQL server is on another machine and is not listening on external interfaces.

To debug this specific problem, you can follow theses steps:

  • Look at your postgresql.conf, sudo vim /etc/postgresql/9.3/main/postgresql.conf
  • Add this line: listen_addresses = '*'
  • Restart the service sudo /etc/init.d/postgresql restart

(Note, the commands above are for ubuntu. Other linux distro or OS may have different path to theses files)

Note: using '*' for listening addresses will listen on all interfaces. If you do '0.0.0.0' then it'll listen for all ipv4 and if you do '::' then it'll listen for all ipv6.

http://www.postgresql.org/docs/9.3/static/runtime-config-connection.html

Can a for loop increment/decrement by more than one?

There is an operator just for this. For example, if I wanted to change a variable i by 3 then:

_x000D_
_x000D_
var someValue = 9;
var Increment  = 3;
for(var i=0;i<someValue;i+=Increment){
//do whatever
}
_x000D_
_x000D_
_x000D_ to decrease, you use -=
_x000D_
_x000D_
var someValue = 3;
var Increment  = 3;
for(var i=9;i>someValue;i+=Increment){
//do whatever
}
_x000D_
_x000D_
_x000D_

Programmatically trigger "select file" dialog box

Make sure you are using binding to get component props in REACT

class FileUploader extends Component {
  constructor (props) {
    super(props);
    this.handleClick = this.handleClick.bind(this);
  }
   onChange=(e,props)=>{
    const files = e.target.files;
    const selectedFile = files[0];
    ProcessFileUpload(selectedFile,props.ProgressCallBack,props.ErrorCallBack,props.CompleatedCallBack,props.BaseURL,props.Location,props.FilesAllowed);
  }
   handleClick = () => {
    this.refs.fileUploader.click();
  }
  render()
  {
  return(
      <div>
        <button type="button" onClick={this.handleClick}>Select File</button>  
        <input type='file' onChange={(e)=>this.onChange(e,this.props)} ref="fileUploader" style={{display:"none"}} />
      </div>)
  }
}