Programs & Examples On #Swapfile

How to prevent vim from creating (and leaving) temporary files?

On Windows add following lines to _vimrc

" store backup, undo, and swap files in temp directory
set directory=$HOME/temp//
set backupdir=$HOME/temp//
set undodir=$HOME/temp//

Git commit with no commit message

When working on an important code update, if you really need an intermediate safepoint you might just do:

git commit -am'.'

or shorter:

git commit -am.

Oracle: how to INSERT if a row doesn't exist

INSERT INTO table
SELECT 'jonny', NULL
  FROM dual -- Not Oracle? No need for dual, drop that line
 WHERE NOT EXISTS (SELECT NULL -- canonical way, but you can select
                               -- anything as EXISTS only checks existence
                     FROM table
                    WHERE name = 'jonny'
                  )

Define a fixed-size list in Java

Yes is posible:

List<Integer> myArrayList = new ArrayList<>(100);

now, the initial capacity of myArrayList will be 100

jQuery: Get selected element tag name

nodeName will give you the tag name in uppercase, while localName will give you the lower case.

$("yourelement")[0].localName 

will give you : yourelement instead of YOURELEMENT

Typescript: How to extend two classes?

I found an up-to-date & unparalleled solution: https://www.npmjs.com/package/ts-mixer

You are welcome :)

Javascript format date / time

Please do not reinvent the wheel. There are many open-source & COTS solutions that already exist to solve this problem.

Please take a look at the following JavaScript libraries:


Demo

I wrote a one-liner using Moment.js below. You can check out the demo here: JSFiddle.

moment('2014-08-20 15:30:00').format('MM/DD/YYYY h:mm a'); // 08/20/2014 3:30 pm

How to create a DataTable in C# and how to add rows?

You can write one liner using DataRow.Add(params object[] values) instead of four lines.

dt.Rows.Add("Ravi", "500");

As you create new DataTable object, there seems no need to Clear DataTable in very next statement. You can also use DataTable.Columns.AddRange to add columns with on statement. Complete code would be.

DataTable dt = new DataTable();
dt.Columns.AddRange(new DataColumn[] { new DataColumn("Name"), new DataColumn("Marks") });     
dt.Rows.Add("Ravi", "500");

Remove a JSON attribute

The selected answer would work for as long as you know the key itself that you want to delete but if it should be truly dynamic you would need to use the [] notation instead of the dot notation.

For example:

var keyToDelete = "key1";
var myObj = {"test": {"key1": "value", "key2": "value"}}

//that will not work.
delete myObj.test.keyToDelete 

instead you would need to use:

delete myObj.test[keyToDelete];

Substitute the dot notation with [] notation for those values that you want evaluated before being deleted.

Dynamic WHERE clause in LINQ

This is the solution I came up with if anyone is interested.

https://kellyschronicles.wordpress.com/2017/12/16/dynamic-predicate-for-a-linq-query/

First we identify the single element type we need to use ( Of TRow As DataRow) and then identify the “source” we are using and tie the identifier to that source ((source As TypedTableBase(Of TRow)). Then we must specify the predicate, or the WHERE clause that is going to be passed (predicate As Func(Of TRow, Boolean)) which will either be returned as true or false. Then we identify how we want the returned information ordered (OrderByField As String). Our function will then return a EnumerableRowCollection(Of TRow), our collection of datarows that have met the conditions of our predicate(EnumerableRowCollection(Of TRow)). This is a basic example. Of course you must make sure your order field doesn’t contain nulls, or have handled that situation properly and make sure your column names (if you are using a strongly typed datasource never mind this, it will rename the columns for you) are standard.

Access-Control-Allow-Origin error sending a jQuery Post to Google API's

I had exactly the same issue and it was not cross domain but the same domain. I just added this line to the php file which was handling the ajax request.

<?php header('Access-Control-Allow-Origin: *'); ?>

It worked like a charm. Thanks to the poster

How to get the full path of the file from a file input

You cannot do so - the browser will not allow this because of security concerns. Although there are workarounds, the fact is that you shouldn't count on this working. The following Stack Overflow questions are relevant here:

In addition to these, the new HTML5 specification states that browsers will need to feed a Windows compatible fakepath into the input type="file" field, ostensibly for backward compatibility reasons.

So trying to obtain the path is worse then useless in newer browsers - you'll actually get a fake one instead.

How to get browser width using JavaScript code?

Update for 2017

My original answer was written in 2009. While it still works, I'd like to update it for 2017. Browsers can still behave differently. I trust the jQuery team to do a great job at maintaining cross-browser consistency. However, it's not necessary to include the entire library. In the jQuery source, the relevant portion is found on line 37 of dimensions.js. Here it is extracted and modified to work standalone:

_x000D_
_x000D_
function getWidth() {_x000D_
  return Math.max(_x000D_
    document.body.scrollWidth,_x000D_
    document.documentElement.scrollWidth,_x000D_
    document.body.offsetWidth,_x000D_
    document.documentElement.offsetWidth,_x000D_
    document.documentElement.clientWidth_x000D_
  );_x000D_
}_x000D_
_x000D_
function getHeight() {_x000D_
  return Math.max(_x000D_
    document.body.scrollHeight,_x000D_
    document.documentElement.scrollHeight,_x000D_
    document.body.offsetHeight,_x000D_
    document.documentElement.offsetHeight,_x000D_
    document.documentElement.clientHeight_x000D_
  );_x000D_
}_x000D_
_x000D_
console.log('Width:  ' +  getWidth() );_x000D_
console.log('Height: ' + getHeight() );
_x000D_
_x000D_
_x000D_


Original Answer

Since all browsers behave differently, you'll need to test for values first, and then use the correct one. Here's a function that does this for you:

function getWidth() {
  if (self.innerWidth) {
    return self.innerWidth;
  }

  if (document.documentElement && document.documentElement.clientWidth) {
    return document.documentElement.clientWidth;
  }

  if (document.body) {
    return document.body.clientWidth;
  }
}

and similarly for height:

function getHeight() {
  if (self.innerHeight) {
    return self.innerHeight;
  }

  if (document.documentElement && document.documentElement.clientHeight) {
    return document.documentElement.clientHeight;
  }

  if (document.body) {
    return document.body.clientHeight;
  }
}

Call both of these in your scripts using getWidth() or getHeight(). If none of the browser's native properties are defined, it will return undefined.

Getting "Cannot call a class as a function" in my React Project

In my case, using JSX a parent component was calling other components without the "<>"

 <ComponentA someProp={someCheck ? ComponentX : ComponentY} />

fix

<ComponentA someProp={someCheck ? <ComponentX /> : <ComponentY />} />

How to check that a string is parseable to a double?

Google's Guava library provides a nice helper method to do this: Doubles.tryParse(String). You use it like Double.parseDouble but it returns null rather than throwing an exception if the string does not parse to a double.

Java Runtime.getRuntime(): getting output from executing a command line program

A quicker way is this:

public static String execCmd(String cmd) throws java.io.IOException {
    java.util.Scanner s = new java.util.Scanner(Runtime.getRuntime().exec(cmd).getInputStream()).useDelimiter("\\A");
    return s.hasNext() ? s.next() : "";
}

Which is basically a condensed version of this:

public static String execCmd(String cmd) throws java.io.IOException {
    Process proc = Runtime.getRuntime().exec(cmd);
    java.io.InputStream is = proc.getInputStream();
    java.util.Scanner s = new java.util.Scanner(is).useDelimiter("\\A");
    String val = "";
    if (s.hasNext()) {
        val = s.next();
    }
    else {
        val = "";
    }
    return val;
}

I know this question is old but I am posting this answer because I think this may be quicker.

Edit (For Java 7 and above)

Need to close Streams and Scanners. Using AutoCloseable for neat code:

public static String execCmd(String cmd) {
    String result = null;
    try (InputStream inputStream = Runtime.getRuntime().exec(cmd).getInputStream();
            Scanner s = new Scanner(inputStream).useDelimiter("\\A")) {
        result = s.hasNext() ? s.next() : null;
    } catch (IOException e) {
        e.printStackTrace();
    }
    return result;
}

Limitations of SQL Server Express

If you switch from Web to Express you will no longer be able to use the SQL Server Agent service so you need to set up a different scheduler for maintenance and backups.

How can I delete all cookies with JavaScript?

There is no 100% solution to delete browser cookies.

The problem is that cookies are uniquely identified by not just by their key "name" but also their "domain" and "path".

Without knowing the "domain" and "path" of a cookie, you cannot reliably delete it. This information is not available through JavaScript's document.cookie. It's not available through the HTTP Cookie header either!

However, if you know the name, path and domain of a cookie, then you can clear it by setting an empty cookie with an expiry date in the past, for example:

function clearCookie(name, domain, path){
    var domain = domain || document.domain;
    var path = path || "/";
    document.cookie = name + "=; expires=" + +new Date + "; domain=" + domain + "; path=" + path;
};

set value of input field by php variable's value

inside the Form, You can use this code. Replace your variable name (i use $variable)

<input type="text" value="<?php echo (isset($variable))?$variable:'';?>">

How to use order by with union all in sql?

select CONCAT(Name, '(',substr(occupation, 1, 1), ')') AS f1
from OCCUPATIONS
union
select temp.str AS f1 from 
(select count(occupation) AS counts, occupation, concat('There are a total of ' ,count(occupation) ,' ', lower(occupation),'s.') As str  from OCCUPATIONS group by occupation order by counts ASC, occupation ASC
 ) As temp
 order by f1

Reference - What does this regex mean?

The Stack Overflow Regular Expressions FAQ

See also a lot of general hints and useful links at the tag details page.


Online tutorials

Quantifiers

Character Classes

Escape Sequences

Anchors

(Also see "Flavor-Specific Information ? Java ? The functions in Matcher")

Groups

Lookarounds

Modifiers

Other:

Common Tasks

Advanced Regex-Fu

Flavor-Specific Information

(Except for those marked with *, this section contains non-Stack Overflow links.)

General information

(Links marked with * are non-Stack Overflow links.)

Examples of regex that can cause regex engine to fail

Tools: Testers and Explainers

(This section contains non-Stack Overflow links.)

Get url parameters from a string in .NET

This is actually very simple, and that worked for me :)

        if (id == "DK")
        {
            string longurl = "selectServer.aspx?country=";
            var uriBuilder = new UriBuilder(longurl);
            var query = HttpUtility.ParseQueryString(uriBuilder.Query);
            query["country"] = "DK";

            uriBuilder.Query = query.ToString();
            longurl = uriBuilder.ToString();
        } 

Multiple INNER JOIN SQL ACCESS

Access requires parentheses in the FROM clause for queries which include more than one join. Try it this way ...

FROM
    ((tbl_employee
    INNER JOIN tbl_netpay
    ON tbl_employee.emp_id = tbl_netpay.emp_id)
    INNER JOIN tbl_gross
    ON tbl_employee.emp_id = tbl_gross.emp_ID)
    INNER JOIN tbl_tax
    ON tbl_employee.emp_id = tbl_tax.emp_ID;

If possible, use the Access query designer to set up your joins. The designer will add parentheses as required to keep the db engine happy.

How to add include path in Qt Creator?

To add global include path use custom command for qmake in Projects/Build/Build Steps section in "Additional arguments" like this: "QT+=your_qt_modules" "DEFINES+=your_defines"

I think that you can use any command from *.pro files in that way.

Calculating Page Load Time In JavaScript

The answer mentioned by @HaNdTriX is a great, but we are not sure if DOM is completely loaded in the below code:

var loadTime = window.performance.timing.domContentLoadedEventEnd- window.performance.timing.navigationStart; 

This works perfectly when used with onload as:

window.onload = function () {
    var loadTime = window.performance.timing.domContentLoadedEventEnd-window.performance.timing.navigationStart; 
    console.log('Page load time is '+ loadTime);
}

Edit 1: Added some context to answer

Note: loadTime is in milliseconds, you can divide by 1000 to get seconds as mentioned by @nycynik

Import Excel Data into PostgreSQL 9.3

The typical answer is this:

  1. In Excel, File/Save As, select CSV, save your current sheet.

  2. transfer to a holding directory on the Pg server the postgres user can access

  3. in PostgreSQL:

    COPY mytable FROM '/path/to/csv/file' WITH CSV HEADER; -- must be superuser
    

But there are other ways to do this too. PostgreSQL is an amazingly programmable database. These include:

  1. Write a module in pl/javaU, pl/perlU, or other untrusted language to access file, parse it, and manage the structure.

  2. Use CSV and the fdw_file to access it as a pseudo-table

  3. Use DBILink and DBD::Excel

  4. Write your own foreign data wrapper for reading Excel files.

The possibilities are literally endless....

position fixed header in html

The position :fixed is differ from the other layout. Once you fixed the position for your header, keep in mind that you have to set the margin-top for the content div.

Sorting arraylist in alphabetical order (case insensitive)

Based on the above mentioned answers, I managed to compare my custom Class Objects like this:

ArrayList<Item> itemList = new ArrayList<>();
...
Collections.sort(itemList, new Comparator<Item>() {
            @Override
            public int compare(Item item, Item t1) {
                String s1 = item.getTitle();
                String s2 = t1.getTitle();
                return s1.compareToIgnoreCase(s2);
            }

        });

jQuery - Detect value change on hidden input field

Since hidden input does not trigger "change" event on change, I used MutationObserver to trigger this instead.

(Sometimes hidden input value changes are done by some other scripts you can't modify)

This does not work in IE10 and below

MutationObserver = window.MutationObserver || window.WebKitMutationObserver;

var trackChange = function(element) {
  var observer = new MutationObserver(function(mutations, observer) {
    if(mutations[0].attributeName == "value") {
        $(element).trigger("change");
    }
  });
  observer.observe(element, {
    attributes: true
  });
}

// Just pass an element to the function to start tracking
trackChange( $("input[name=foo]")[0] );

How to convert currentTimeMillis to a date in Java?

Easiest way:

private String millisToDate(long millis){

    return DateFormat.getDateInstance(DateFormat.SHORT).format(millis);
    //You can use DateFormat.LONG instead of SHORT

}

UIView touch event in controller

For swift 4

@IBOutlet weak var someView: UIView!  
let gesture = UITapGestureRecognizer(target: self, action:  #selector (self.someAction (_:)))
self.someView.addGestureRecognizer(gesture)

@objc func someAction(_ sender:UITapGestureRecognizer){
    print("view was clicked")
}

JNI converting jstring to char *

Here's a a couple of useful link that I found when I started with JNI

http://en.wikipedia.org/wiki/Java_Native_Interface
http://download.oracle.com/javase/1.5.0/docs/guide/jni/spec/functions.html

concerning your problem you can use this

JNIEXPORT void JNICALL Java_ClassName_MethodName(JNIEnv *env, jobject obj, jstring javaString)   
{
   const char *nativeString = env->GetStringUTFChars(javaString, 0);

   // use your string

   env->ReleaseStringUTFChars(javaString, nativeString);
}

JAVA_HOME does not point to the JDK

I just copied tools.jar file from JDK\lib folder to JRE\lib folder. Since then it worked like a champ.

Is it safe to shallow clone with --depth 1, create commits, and pull updates again?

See some of the answers to my similar question why-cant-i-push-from-a-shallow-clone and the link to the recent thread on the git list.

Ultimately, the 'depth' measurement isn't consistent between repos, because they measure from their individual HEADs, rather than (a) your Head, or (b) the commit(s) you cloned/fetched, or (c) something else you had in mind.

The hard bit is getting one's Use Case right (i.e. self-consistent), so that distributed, and therefore probably divergent repos will still work happily together.

It does look like the checkout --orphan is the right 'set-up' stage, but still lacks clean (i.e. a simple understandable one line command) guidance on the "clone" step. Rather it looks like you have to init a repo, set up a remote tracking branch (you do want the one branch only?), and then fetch that single branch, which feels long winded with more opportunity for mistakes.

Edit: For the 'clone' step see this answer

Can't access object property, even though it shows up in a console log

Check if inside the object there's an array of objects. I had a similar issue with a JSON:

    "terms": {
        "category": [
            {
                "ID": 4,
                "name": "Cirugia",
                "slug": "cirugia",
                "description": "",
                "taxonomy": "category",
                "parent": null,
                "count": 68,
                "link": "http://distritocuatro.mx/enarm/category/cirugia/"
            }
        ]
    }

I tried to access the 'name' key from 'category' and I got the undefined error, because I was using:

var_name = obj_array.terms.category.name

Then I realised it has got square brackets, that means that it has an array of objects inside the category key, because it can have more than one category object. So, in order to get the 'name' key I used this:

var_name = obj_array.terms.category[0].name

And That does the trick.

Maybe it's too late for this answer, but I hope someone with the same problem will find this as I did before finding the Solution :)

in a "using" block is a SqlConnection closed on return or exception?

Yes to both questions. The using statement gets compiled into a try/finally block

using (SqlConnection connection = new SqlConnection(connectionString))
{
}

is the same as

SqlConnection connection = null;
try
{
    connection = new SqlConnection(connectionString);
}
finally
{
   if(connection != null)
        ((IDisposable)connection).Dispose();
}

Edit: Fixing the cast to Disposable http://msdn.microsoft.com/en-us/library/yh598w02.aspx

How do I start an activity from within a Fragment?

You should do it with getActivity().startActivity(myIntent)

How add unique key to existing table (with non uniques rows)

For MySQL:

ALTER TABLE MyTable ADD MyId INT AUTO_INCREMENT PRIMARY KEY;

Return file in ASP.Net Core Web API

Here is a simplistic example of streaming a file:

using System.IO;
using Microsoft.AspNetCore.Mvc;
[HttpGet("{id}")]
public async Task<FileStreamResult> Download(int id)
{
    var path = "<Get the file path using the ID>";
    var stream = File.OpenRead(path);
    return new FileStreamResult(stream, "application/octet-stream");
}

Note:

Be sure to use FileStreamResult from Microsoft.AspNetCore.Mvc and not from System.Web.Mvc.

Getting A File's Mime Type In Java

This is the simplest way I found for doing this:

byte[] byteArray = ...
InputStream is = new BufferedInputStream(new ByteArrayInputStream(byteArray));
String mimeType = URLConnection.guessContentTypeFromStream(is);

What are the differences between WCF and ASMX web services?

There's a lot of talks going on regarding the simplicity of asmx web services over WCF. Let me clarify few points here.

  • Its true that novice web service developers will get started easily in asmx web services. Visual Studio does all the work for them and readily creates a Hello World project.
  • But if you can learn WCF (which off course wont take much time) then you can get to see that WCF is also quite simple, and you can go ahead easily.
  • Its important to remember that these said complexities in WCF are actually attributed to the beautiful features that it brings along with it. There are addressing, bindings, contracts and endpoints, services & clients all mentioned in the config file. The beauty is your business logic is segregated and maintained safely. Tomorrow if you need to change the binding from basicHttpBinding to netTcpBinding you can easily create a binding in config file and use it. So all the changes related to clients, communication channels, bindings etc are to be done in the configuration leaving the business logic safe & intact, which makes real good sense.
  • WCF "web services" are part of a much broader spectrum of remote communication enabled through WCF. You will get a much higher degree of flexibility and portability doing things in WCF than through traditional ASMX because WCF is designed, from the ground up, to summarize all of the different distributed programming infrastructures offered by Microsoft. An endpoint in WCF can be communicated with just as easily over SOAP/XML as it can over TCP/binary and to change this medium is simply a configuration file mod. In theory, this reduces the amount of new code needed when porting or changing business needs, targets, etc.
  • Web Services can be accessed only over HTTP & it works in stateless environment, where WCF is flexible because its services can be hosted in different types of applications. You can host your WCF services in Console, Windows Services, IIS & WAS, which are again different ways of creating new projects in Visual Studio.
  • ASMX is older than WCF, and anything ASMX can do so can WCF (and more). Basically you can see WCF as trying to logically group together all the different ways of getting two apps to communicate in the world of Microsoft; ASMX was just one of these many ways and so is now grouped under the WCF umbrella of capabilities.
  • You will always like to use Visual Studio for NET 4.0 or 4.5 as it makes life easy while creating WCF services.
  • The major difference is that Web Services Use XmlSerializer. But WCF Uses DataContractSerializer which is better in Performance as compared to XmlSerializer. That's why WCF performs way better than other communication technology counterparts from .NET like asmx, .NET remoting etc.

Not to forget that I was one of those guys who liked asmx services more than WCF, but that time I was not well aware of WCF services and its capabilities. I was scared of the WCF configurations. But I dared and and tried writing few WCF services of my own, and when I learnt more of WCF, now I have no inhibitions about WCF and I recommend them to anyone & everyone. Happy coding!!!

warning: control reaches end of non-void function [-Wreturn-type]

You can also use EXIT_SUCCESS instead of return 0;. The macro EXIT_SUCCESS is actually defined as zero, but makes your program more readable.

Run a string as a command within a Bash script

To see all commands that are being executed by the script, add the -x flag to your shabang line, and execute the command normally:

#! /bin/bash -x

matchdir="/home/joao/robocup/runner_workdir/matches/testmatch/"

teamAComm="`pwd`/a.sh"
teamBComm="`pwd`/b.sh"
include="`pwd`/server_official.conf"
serverbin='/usr/local/bin/rcssserver'

cd $matchdir
$serverbin include="$include" server::team_l_start="${teamAComm}" server::team_r_start="${teamBComm}" CSVSaver::save='true' CSVSaver::filename='out.csv'

Then if you sometimes want to ignore the debug output, redirect stderr somewhere.

Pass Array Parameter in SqlCommand

try it like this

StringBuilder sb = new StringBuilder(); 
foreach (ListItem item in ddlAge.Items) 
{ 
     if (item.Selected) 
     { 
          string sqlCommand = "SELECT * from TableA WHERE Age IN (@Age)"; 
          SqlConnection sqlCon = new SqlConnection(connectString); 
          SqlCommand sqlComm = new SqlCommand(); 
          sqlComm.Connection = sqlCon; 
          sqlComm.CommandType = System.Data.CommandType.Text; 
          sqlComm.CommandText = sqlCommand; 
          sqlComm.CommandTimeout = 300; 
          sqlComm.Parameters.Add("@Age", SqlDbType.NVarChar);
          sb.Append(item.Text + ","); 
          sqlComm.Parameters["@Age"].Value = sb.ToString().TrimEnd(',');
     } 
} 

How to use systemctl in Ubuntu 14.04

I just encountered this problem myself and found that Ubuntu 14.04 uses Upstart instead of Systemd, so systemctl commands will not work. This changed in 15.04, so one way around this would be to update your ubuntu install.

If this is not an option for you (it's not for me right now), you need to find the Upstart command that does what you need to do.

For enable, the generic looks to be the following:

update-rc.d <service> enable

Link to Ubuntu documentation: https://wiki.ubuntu.com/SystemdForUpstartUsers

Spring JUnit: How to Mock autowired component in autowired component

I created blog post on the topic. It contains also link to Github repository with working example.

The trick is using test configuration, where you override original spring bean with fake one. You can use @Primary and @Profile annotations for this trick.

C++11 reverse range-based for-loop

Actually Boost does have such adaptor: boost::adaptors::reverse.

#include <list>
#include <iostream>
#include <boost/range/adaptor/reversed.hpp>

int main()
{
    std::list<int> x { 2, 3, 5, 7, 11, 13, 17, 19 };
    for (auto i : boost::adaptors::reverse(x))
        std::cout << i << '\n';
    for (auto i : x)
        std::cout << i << '\n';
}

How to remove specific object from ArrayList in Java?

use this code

test.remove(test.indexOf(obj));

test is your ArrayList and obj is the Object, first you find the index of obj in ArrayList and then you remove it from the ArrayList.

How do I hide an element when printing a web page?

Here is a simple solution put this CSS

@media print{
   .noprint{
       display:none;
   }
}

and here is the HTML

<div class="noprint">
    element that need to be hidden when printing
</div>

String replacement in batch file

This works fine

@echo off    
set word=table    
set str=jump over the chair    
set rpl=%str:chair=%%word%    
echo %rpl%

Join/Where with LINQ and Lambda

It could be something like

var myvar = from a in context.MyEntity
            join b in context.MyEntity2 on a.key equals b.key
            select new { prop1 = a.prop1, prop2= b.prop1};

Checking for multiple conditions using "when" on single task in ansible

You can use like this.

when: condition1 == "condition1" or condition2 == "condition2"

Link to official docs: The When Statement.

Also Please refer to this gist: https://gist.github.com/marcusphi/6791404

Editing an item in a list<T>

class1 item = lst[index];
item.foo = bar;

JS search in object values

Something like this:

var objects = [
  {
    "foo" : "bar",
    "bar" : "sit"
  },
  {
    "foo" : "lorem",
    "bar" : "ipsum"
  },
  {
    "foo" : "dolor",
    "bar" : "amet"
  }
];

var results = [];

var toSearch = "lo";

for(var i=0; i<objects.length; i++) {
  for(key in objects[i]) {
    if(objects[i][key].indexOf(toSearch)!=-1) {
      results.push(objects[i]);
    }
  }
}

The results array will contain all matched objects.

If you search for 'lo', the result will be like:

[{ foo="lorem", bar="ipsum"}, { foo="dolor", bar="amet"}]

NEW VERSION - Added trim code, code to ensure no duplicates in result set.

function trimString(s) {
  var l=0, r=s.length -1;
  while(l < s.length && s[l] == ' ') l++;
  while(r > l && s[r] == ' ') r-=1;
  return s.substring(l, r+1);
}

function compareObjects(o1, o2) {
  var k = '';
  for(k in o1) if(o1[k] != o2[k]) return false;
  for(k in o2) if(o1[k] != o2[k]) return false;
  return true;
}

function itemExists(haystack, needle) {
  for(var i=0; i<haystack.length; i++) if(compareObjects(haystack[i], needle)) return true;
  return false;
}

var objects = [
  {
    "foo" : "bar",
    "bar" : "sit"
  },
  {
    "foo" : "lorem",
    "bar" : "ipsum"
  },
  {
    "foo" : "dolor blor",
    "bar" : "amet blo"
  }
];

function searchFor(toSearch) {
  var results = [];
  toSearch = trimString(toSearch); // trim it
  for(var i=0; i<objects.length; i++) {
    for(var key in objects[i]) {
      if(objects[i][key].indexOf(toSearch)!=-1) {
        if(!itemExists(results, objects[i])) results.push(objects[i]);
      }
    }
  }
  return results;
}

console.log(searchFor('lo '));

Fastest way to determine if an integer's square root is an integer

It ought to be possible to pack the 'cannot be a perfect square if the last X digits are N' much more efficiently than that! I'll use java 32 bit ints, and produce enough data to check the last 16 bits of the number - that's 2048 hexadecimal int values.

...

Ok. Either I have run into some number theory that is a little beyond me, or there is a bug in my code. In any case, here is the code:

public static void main(String[] args) {
    final int BITS = 16;

    BitSet foo = new BitSet();

    for(int i = 0; i< (1<<BITS); i++) {
        int sq = (i*i);
        sq = sq & ((1<<BITS)-1);
        foo.set(sq);
    }

    System.out.println("int[] mayBeASquare = {");

    for(int i = 0; i< 1<<(BITS-5); i++) {
        int kk = 0;
        for(int j = 0; j<32; j++) {
            if(foo.get((i << 5) | j)) {
                kk |= 1<<j;
            }
        }
        System.out.print("0x" + Integer.toHexString(kk) + ", ");
        if(i%8 == 7) System.out.println();
    }
    System.out.println("};");
}

and here are the results:

(ed: elided for poor performance in prettify.js; view revision history to see.)

Explain the concept of a stack frame in a nutshell

"A call stack is composed of stack frames..." — Wikipedia

A stack frame is a thing that you put on the stack. They are data structures that contain information about subroutines to call.

Error:(23, 17) Failed to resolve: junit:junit:4.12

If any one get error "failed-to-resolve-junitjunit4-12" then go to HTTP PRoxy setting check your internet connection. if you are using any proxy server at school / college then set your proxy setting and test connect if it successful then apply setting and run again gradle you will get resolve all error. I try this and i resolve all errors. Note : no need to remove Junit....!! Umair

Why are static variables considered evil?

Seems to me that you're asking about static variables but you also point out static methods in your examples.

Static variables are not evil - they have its adoption as global variables like constants in most cases combined with final modifier, but as it said don't overuse them.

Static methods aka utility method. It isn't generally a bad practice to use them but major concern is that they might obstruct testing.

As a example of great java project that use a lot of statics and do it right way please look at Play! framework. There is also discussion about it in SO.

Static variables/methods combined with static import are also widely used in libraries that facilitate declarative programming in java like: make it easy or Hamcrest. It wouldn't be possible without a lot of static variables and methods.

So static variables (and methods) are good but use them wisely!

How to write an ArrayList of Strings into a text file?

If you want to serialize the ArrayList object to a file so you can read it back in again later use ObjectOuputStream/ObjectInputStream writeObject()/readObject() since ArrayList implements Serializable. It's not clear to me from your question if you want to do this or just write each individual item. If so then Andrey's answer will do that.

How to install PyQt4 on Windows using pip?

With current latest python 3.6.5

pip3 install PyQt5

works fine

Pass an array of integers to ASP.NET Web API?

My solution was to create an attribute to validate strings, it does a bunch of extra common features, including regex validation that you can use to check for numbers only and then later I convert to integers as needed...

This is how you use:

public class MustBeListAndContainAttribute : ValidationAttribute
{
    private Regex regex = null;
    public bool RemoveDuplicates { get; }
    public string Separator { get; }
    public int MinimumItems { get; }
    public int MaximumItems { get; }

    public MustBeListAndContainAttribute(string regexEachItem,
        int minimumItems = 1,
        int maximumItems = 0,
        string separator = ",",
        bool removeDuplicates = false) : base()
    {
        this.MinimumItems = minimumItems;
        this.MaximumItems = maximumItems;
        this.Separator = separator;
        this.RemoveDuplicates = removeDuplicates;

        if (!string.IsNullOrEmpty(regexEachItem))
            regex = new Regex(regexEachItem, RegexOptions.Compiled | RegexOptions.Singleline | RegexOptions.IgnoreCase);
    }

    protected override ValidationResult IsValid(object value, ValidationContext validationContext)
    {
        var listOfdValues = (value as List<string>)?[0];

        if (string.IsNullOrWhiteSpace(listOfdValues))
        {
            if (MinimumItems > 0)
                return new ValidationResult(this.ErrorMessage);
            else
                return null;
        };

        var list = new List<string>();

        list.AddRange(listOfdValues.Split(new[] { Separator }, System.StringSplitOptions.RemoveEmptyEntries));

        if (RemoveDuplicates) list = list.Distinct().ToList();

        var prop = validationContext.ObjectType.GetProperty(validationContext.MemberName);
        prop.SetValue(validationContext.ObjectInstance, list);
        value = list;

        if (regex != null)
            if (list.Any(c => string.IsNullOrWhiteSpace(c) || !regex.IsMatch(c)))
                return new ValidationResult(this.ErrorMessage);

        return null;
    }
}

How to check if a directory containing a file exist?

To check if a folder exists or not, you can simply use the exists() method:

// Create a File object representing the folder 'A/B'
def folder = new File( 'A/B' )

// If it doesn't exist
if( !folder.exists() ) {
  // Create all folders up-to and including B
  folder.mkdirs()
}

// Then, write to file.txt inside B
new File( folder, 'file.txt' ).withWriterAppend { w ->
  w << "Some text\n"
}

git - Your branch is ahead of 'origin/master' by 1 commit

git reset HEAD^

then the modified files should show up.

You could move the modified files into a new branch

use,

git checkout -b newbranch

git checkout commit -m "files modified"

git push origin newbranch

git checkout master

then you should be on a clean branch, and your changes should be stored in newbranch. You could later just merge this change into the master branch

Java swing application, close one window and open another when button is clicked

Call below method just after calling the method for opening new window, this will close the current window.

private void close(){
    WindowEvent windowEventClosing = new WindowEvent(this, WindowEvent.WINDOW_CLOSING);
    Toolkit.getDefaultToolkit().getSystemEventQueue().postEvent(windowEventClosing);
}

Also in properties of JFrame, make sure defaultCloseOperation is set as DISPOSE.

How to change the cursor into a hand when a user hovers over a list item?

For complete cross browser, use:

cursor: pointer;
cursor: hand;

python to arduino serial read & write

First you have to install a module call Serial. To do that go to the folder call Scripts which is located in python installed folder. If you are using Python 3 version it's normally located in location below,

C:\Python34\Scripts  

Once you open that folder right click on that folder with shift key. Then click on 'open command window here'. After that cmd will pop up. Write the below code in that cmd window,

pip install PySerial

and press enter.after that PySerial module will be installed. Remember to install the module u must have an INTERNET connection.


after successfully installed the module open python IDLE and write down the bellow code and run it.

import serial
# "COM11" is the port that your Arduino board is connected.set it to port that your are using        
ser = serial.Serial("COM11", 9600)
while True:
    cc=str(ser.readline())
    print(cc[2:][:-5])   

Bootstrap 3 Align Text To Bottom of Div

You can do this:

CSS:

#container {
    height:175px;
}

#container h3{
    position:absolute;
    bottom:0;
    left:0;
}

Then in HTML:

<div class="row">
    <div class="col-sm-6">
        <img src="//placehold.it/600x300" alt="Logo" />
    </div>
    <div id="container" class="col-sm-6">
        <h3>Some Text</h3>
    </div>
</div>

EDIT: add the <

How can I adjust DIV width to contents

Try width: max-content to adjust the width of the div by it's content.

<!DOCTYPE html>
<html>
<head>
<style>
div.ex1 {
  width:500px;
  margin: auto;
  border: 3px solid #73AD21;
}

div.ex2 {
  width: max-content;
  margin: auto;
  border: 3px solid #73AD21;
}
</style>
</head>
<body>

<div class="ex1">This div element has width 500px;</div>
<br>
<div class="ex2">Width by content size</div>

</body>
</html>

Exception Error c0000005 in VC++

I was having the same problem while running bulk tests for an assignment. Turns out when I relocated some iostream operations (printing to console) from class constructor to a method in class it was solved.

I assume it was something to do with iostream manipulations in the constructor.

Here is the fix:

// Before
CommandPrompt::CommandPrompt() : afs(nullptr), aff(nullptr) {
    cout << "Some text I was printing.." << endl;
};


// After
CommandPrompt::CommandPrompt() : afs(nullptr), aff(nullptr) {

};

Please feel free to explain more what the error is behind the scenes since it goes beyond my cpp knowledge.

How to convert array to a string using methods other than JSON?

serialize() is the function you are looking for. It will return a string representation of its input array or object in a PHP-specific internal format. The string may be converted back to its original form with unserialize().

But beware, that not all objects are serializable, or some may be only partially serializable and unable to be completely restored with unserialize().

$array = array(1,2,3,'foo');
echo serialize($array);

// Prints
a:4:{i:0;i:1;i:1;i:2;i:2;i:3;i:3;s:3:"foo";}

Javascript "Not a Constructor" Exception while creating objects

I've googled around also and found this solution:

You have a variable Project somewhere that is not a function. Then the new operator will complain about it. Try console.log(Project) at the place where you would have used it as a construcotr, and you will find it.

PHP: cannot declare class because the name is already in use

Another option to include_once or require_once is to use class autoloading. http://php.net/manual/en/language.oop5.autoload.php

Evaluate empty or null JSTL c tags

This code is correct but if you entered a lot of space (' ') instead of null or empty string return false.

To correct this use regular expresion (this code below check if the variable is null or empty or blank the same as org.apache.commons.lang.StringUtils.isNotBlank) :

<%@ taglib uri="http://java.sun.com/jsp/jstl/functions" prefix="fn" %>
        <c:if test="${not empty description}">
            <c:set var="description" value="${fn:replace(description, ' ', '')}" />
            <c:if test="${not empty description}">
                  The description is not blank.
            </c:if>
        </c:if>

jQuery UI - Draggable is not a function?

Instead of

<script src="http://ajax.googleapis.com/ajax/libs/jquery/1.4.1/jquery.min.js" type="text/javascript"></script>    
<script src="http://ajax.googleapis.com/ajax/libs/jqueryui/1.8.1/jquery-ui.min.js"></script>

Use

  <script src="http://ajax.googleapis.com/ajax/libs/jquery/1.11.2/jquery.min.js"></script>  
  <script src="https://ajax.googleapis.com/ajax/libs/jqueryui/1.11.4/jquery-ui.min.js" type="text/javascript"></script>

Insert a line break in mailto body

I would suggest you try the html tag <br>, in case your marketing application will recognize it.

I use %0D%0A. This should work as long as the email is HTML formatted.

<a href="mailto:[email protected]?subject=Subscribe&body=Lastame%20%3A%0D%0AFirstname%20%3A"><img alt="Subscribe" class="center" height="50" src="subscribe.png" style="width: 137px; height: 50px; color: #4da6f7; font-size: 20px; display: block;" width="137"></a>

You will likely want to take out the %20 before Firstname, otherwise you will have a space as the first character on the next line.

A note, when I tested this with your code, it worked (along with some extra spacing). Are you using a mail client that doesn't allow HTML formatting?

sudo: docker-compose: command not found

Or, just add your binary path into the PATH. At the end of the bashrc:

... 
export PATH=$PATH:/home/user/.local/bin/

save the file and run:

source .bashrc

and the command will work.

Plot multiple lines in one graph

The answer by @Federico Giorgi was a very good answer. It helpt me. Therefore, I did the following, in order to produce multiple lines in the same plot from the data of a single dataset, I used a for loop. Legend can be added as well.

plot(tab[,1],type="b",col="red",lty=1,lwd=2, ylim=c( min( tab, na.rm=T ),max( tab, na.rm=T ) )  )
for( i in 1:length( tab )) { [enter image description here][1]
lines(tab[,i],type="b",col=i,lty=1,lwd=2)
  } 
axis(1,at=c(1:nrow(tab)),labels=rownames(tab))

How can I drop a table if there is a foreign key constraint in SQL Server?

Type this .... SET foreign_key_checks = 0;
delete your table then type SET foreign_key_checks = 1;

MySQL – Temporarily disable Foreign Key Checks or Constraints

while-else-loop

Assuming you are coming from Python and accept this as the same thing:

def setLinkerAt(value, rowIndex):
    isEnough = lambda i: return i < dataColLinker.count()
    while (not isEnough(rowIndex)):
        dataColLinker.append(value)
    else:
        dataColLinker[rowIndex] = value 

The most similar I could come up with was:

public void setLinkerAt( int value, int rowIndex) {
    isEnough = (i) -> { return i < dataColLine.size; }
    if(isEnough()){
        dataColLinker.set(rowIndex, value);
    }
    else while(!isEnough(rowInex)) {
        dataColLinker.add(value);
    }

Note the need for the logic, and the reverse logic. I'm not sure this is a great solution (duplication of the logic), but the braceless else is the closest syntax I could think of, while maintaining the same act of not executing the logic more than required.

Assert equals between 2 Lists in Junit

Don't reinvent the wheel!

There's a Google Code library that does this for you: Hamcrest

[Hamcrest] Provides a library of matcher objects (also known as constraints or predicates) allowing 'match' rules to be defined declaratively, to be used in other frameworks. Typical scenarios include testing frameworks, mocking libraries and UI validation rules.

How can I add a hint or tooltip to a label in C# Winforms?

Just to share my idea...

I created a custom class to inherit the Label class. I added a private variable assigned as a Tooltip class and a public property, TooltipText. Then, gave it a MouseEnter delegate method. This is an easy way to work with multiple Label controls and not have to worry about assigning your Tooltip control for each Label control.

    public partial class ucLabel : Label
    {
        private ToolTip _tt = new ToolTip();

        public string TooltipText { get; set; }

        public ucLabel() : base() {
            _tt.AutoPopDelay = 1500;
            _tt.InitialDelay = 400;
//            _tt.IsBalloon = true;
            _tt.UseAnimation = true;
            _tt.UseFading = true;
            _tt.Active = true;
            this.MouseEnter += new EventHandler(this.ucLabel_MouseEnter);
        }

        private void ucLabel_MouseEnter(object sender, EventArgs ea)
        {
            if (!string.IsNullOrEmpty(this.TooltipText))
            {
                _tt.SetToolTip(this, this.TooltipText);
                _tt.Show(this.TooltipText, this.Parent);
            }
        }
    }

In the form or user control's InitializeComponent method (the Designer code), reassign your Label control to the custom class:

this.lblMyLabel = new ucLabel();

Also, change the private variable reference in the Designer code:

private ucLabel lblMyLabel;

Setting Java heap space under Maven 2 on Windows

On the Mac: Instead of JAVA_OPTS and MAVEN_OPTS, use _JAVA_OPTIONS instead. This works!

Gray out image with CSS?

Does it have to be gray? You could just set the opacity of the image lower (to dull it). Alternatively, you could create a <div> overlay and set that to be gray (change the alpha to get the effect).

  • html:

    <div id="wrapper">
        <img id="myImage" src="something.jpg" />
    </div>
    
  • css:

    #myImage {
        opacity: 0.4;
        filter: alpha(opacity=40); /* msie */
    }
    
    /* or */
    
    #wrapper {
        opacity: 0.4;
        filter: alpha(opacity=40); /* msie */
        background-color: #000;
    }
    

Printing Even and Odd using two Threads in Java

public class Main {
    public static void main(String[] args) throws Exception{
        int N = 100;
        PrintingThread oddNumberThread = new PrintingThread(N - 1);
        PrintingThread evenNumberThread = new PrintingThread(N);
        oddNumberThread.start();
        // make sure that even thread only start after odd thread
        while (!evenNumberThread.isAlive()) {
            if(oddNumberThread.isAlive()) {
                evenNumberThread.start();
            } else {
                Thread.sleep(100);
            }
        }

    }
}

class PrintingThread extends Thread {
    private static final Object object = new Object(); // lock for both threads
    final int N;
    // N determines whether given thread is even or odd
    PrintingThread(int N) {
        this.N = N;
    }

    @Override
    public void run() {
        synchronized (object) {
            int start = N % 2 == 0 ? 2 : 1; // if N is odd start from 1 else start from 0
            for (int i = start; i <= N; i = i + 2) {
                System.out.println(i);
                try {
                    object.notify(); // will notify waiting thread
                    object.wait(); // will make current thread wait
                } catch (InterruptedException e) {
                    e.printStackTrace();
                }
            }
        }
    }
}

java.lang.ClassNotFoundException: org.springframework.boot.SpringApplication Maven

The answer to the above question is "none of the above". When you download new STS it won't support the old Spring Boot parent version. Just update parent version with latest comes with STS it will work.

<parent>
    <groupId>org.springframework.boot</groupId>
    <artifactId>spring-boot-starter-parent</artifactId>
    <version>1.5.8.RELEASE</version>
    <relativePath/> <!-- lookup parent from repository -->
</parent>

If you have problem getting the latest, just create a new Spring Starter Project. Go to File->New->Spring Start Project and create a demo project you will get the latest parent version, change your version with that all will work. I do this every time I change STS.

What to do on TransactionTooLargeException

If you need to investigate which Parcel is causing your crash, you should consider trying TooLargeTool.

(I found this as a comment from @Max Spencer under the accepted answer and it was helpful in my case.)

How to start activity in another application?

If you guys are facing "Permission Denial: starting Intent..." error or if the app is getting crash without any reason during launching the app - Then use this single line code in Manifest

android:exported="true"

Please be careful with finish(); , if you missed out it the app getting frozen. if its mentioned the app would be a smooth launcher.

finish();

The other solution only works for two activities that are in the same application. In my case, application B doesn't know class com.example.MyExampleActivity.class in the code, so compile will fail.

I searched on the web and found something like this below, and it works well.

Intent intent = new Intent();
intent.setComponent(new ComponentName("com.example", "com.example.MyExampleActivity"));
startActivity(intent);

You can also use the setClassName method:

Intent intent = new Intent(Intent.ACTION_MAIN);
intent.setClassName("com.hotfoot.rapid.adani.wheeler.android", "com.hotfoot.rapid.adani.wheeler.android.view.activities.MainActivity");
startActivity(intent);
finish();

You can also pass the values from one app to another app :

Intent launchIntent = getApplicationContext().getPackageManager().getLaunchIntentForPackage("com.hotfoot.rapid.adani.wheeler.android.LoginActivity");
if (launchIntent != null) {
    launchIntent.putExtra("AppID", "MY-CHILD-APP1");
    launchIntent.putExtra("UserID", "MY-APP");
    launchIntent.putExtra("Password", "MY-PASSWORD");
    startActivity(launchIntent);
    finish();
} else {
    Toast.makeText(getApplicationContext(), " launch Intent not available", Toast.LENGTH_SHORT).show();
}

How to install an apk on the emulator in Android Studio?

Just download the apk from talkback website

Drag the downloaded apk to the started emulator, Go to settings on emulator > Search for talkback, you will now find it there

How to concatenate two strings in SQL Server 2005

I got a easy solution which will select from database table and let you do easily.

SELECT b.FirstName + b.LastName FROM tbl_Users b WHERE b.Id='11'

You can easily add a space there if you try

SELECT b.FirstName +' '+ b.LastName FROM Users b WHERE b.Id='23'

Here you can combine as much as your table have.

AngularJS format JSON string output

If you want to format the JSON and also do some syntax highlighting, you can use the ng-prettyjson directive. See the npm package.

Here is how to use it: <pre pretty-json="jsonObject"></pre>

For homebrew mysql installs, where's my.cnf?

in my system it was

nano /usr/local/etc/my.cnf.default 

as template and

nano /usr/local/etc/my.cnf

as working.

Set Response Status Code

As written before, but for beginner like me don't forget to include the return.

$this->response->statusCode(200);
return $this->response;

How to do a timer in Angular 5

You can simply use setInterval to create such timer in Angular, Use this Code for timer -

timeLeft: number = 60;
  interval;

startTimer() {
    this.interval = setInterval(() => {
      if(this.timeLeft > 0) {
        this.timeLeft--;
      } else {
        this.timeLeft = 60;
      }
    },1000)
  }

  pauseTimer() {
    clearInterval(this.interval);
  }

<button (click)='startTimer()'>Start Timer</button>
<button (click)='pauseTimer()'>Pause</button>

<p>{{timeLeft}} Seconds Left....</p>

Working Example

Another way using Observable timer like below -

import { timer } from 'rxjs';

observableTimer() {
    const source = timer(1000, 2000);
    const abc = source.subscribe(val => {
      console.log(val, '-');
      this.subscribeTimer = this.timeLeft - val;
    });
  }

<p (click)="observableTimer()">Start Observable timer</p> {{subscribeTimer}}

Working Example

For more information read here

C++ template constructor

Some points:

  • If you declare any constructor(including a templated one), the compiler will refrain from declaring a default constructor.
  • Unless you declare a copy-constructor (for class X one that takes X or X& or X const &) the compiler will generate the default copy-constructor.
  • If you provide a template constructor for class X which takes T const & or T or T& then the compiler will nevertheless generate a default non-templated copy-constructor, even though you may think that it shouldn't because when T = X the declaration matches the copy-constructor declaration.
  • In the latter case you may want to provide a non-templated copy-constructor along with the templated one. They will not conflict. When X is passed the nontemplated will be called. Otherwise the templated

HTH

Initial size for the ArrayList

If you want to add 10 items to your ArrayList you may try that:

for (int i = 0; i < 10; i++)
    arr.add(i);

If you have already declare an array size variable you would use the variable size instead of number '10'

Merging 2 branches together in GIT

If you want to merge changes in SubBranch to MainBranch

  1. you should be on MainBranch git checkout MainBranch
  2. then run merge command git merge SubBranch

Calculate mean and standard deviation from a vector of samples in C++ using Boost

//means deviation in c++

/A deviation that is a difference between an observed value and the true value of a quantity of interest (such as a population mean) is an error and a deviation that is the difference between the observed value and an estimate of the true value (such an estimate may be a sample mean) is a residual. These concepts are applicable for data at the interval and ratio levels of measurement./

#include <iostream>
#include <conio.h>
using namespace std;

/* run this program using the console pauser or add your own getch,     system("pause") or input loop */

int main(int argc, char** argv)
{
int i,cnt;
cout<<"please inter count:\t";
cin>>cnt;
float *num=new float [cnt];
float   *s=new float [cnt];
float sum=0,ave,M,M_D;

for(i=0;i<cnt;i++)
{
    cin>>num[i];
    sum+=num[i];    
}
ave=sum/cnt;
for(i=0;i<cnt;i++)
{
s[i]=ave-num[i];    
if(s[i]<0)
{
s[i]=s[i]*(-1); 
}
cout<<"\n|ave - number| = "<<s[i];  
M+=s[i];    
}
M_D=M/cnt;
cout<<"\n\n Average:             "<<ave;
cout<<"\n M.D(Mean Deviation): "<<M_D;
getch();
return 0;

}

Convert Java Object to JsonNode in Jackson

As of Jackson 1.6, you can use:

JsonNode node = mapper.valueToTree(map);

or

JsonNode node = mapper.convertValue(object, JsonNode.class);

Source: is there a way to serialize pojo's directly to treemodel?

Angular 4 img src is not found

Well, the problem was that, somehow, the path was not recognized when was inserted in src by a variable. I had to create a variable like this:

path:any = require("../../img/myImage.png");

and then I can use it in src. Thanks everyone!

How to quickly test some javascript code?

Install firebug: http://getfirebug.com/logging . You can use its console to test Javascript code. Google Chrome comes with Web Inspector in which you can do the same. IE and Safari also have Web Developer tools in which you can test Javascript.

jQuery check/uncheck radio button onclick

Improved version of answer from Jurrie

$('#myRadio').off('click').on('click', function() {
  if ($(this).data('checked')) {
    $(this).removeAttr('checked');
    $(this).data('checked', false);
  } else {
    $(this).data('checked', true);
  }
});

Live Demo

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

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

Follow these steps:

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

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

Here, create an folder called Server

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

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

IE throws JavaScript Error: The value of the property 'googleMapsQuery' is null or undefined, not a Function object (works in other browsers)

In my particular case, I had a similar error on a legacy website used in my organization. To solve the issue, I had to list the website a a "Trusted site".

To do so:

  • Click the Tools button, and then Internet options.
  • Go on the Security tab.
  • Click on Trusted sites and then on the sites button.
  • Enter the url of the website and click on Add.

I'm leaving this here in the remote case it will help someone.

How do I make an Android EditView 'Done' button and hide the keyboard when clicked?

android:imeActionLabel="Done" 
android:singleLine="true"

In the XML file works just fine. But this will also cause the editText to keep typing in a single line which you may not want. So adding following to your code will make sure that you won't end up typing everything on a single line.

mainText.setHorizontallyScrolling(false);
mainText.setMaxLines("Maximum integer value that you want to provide");

Can there exist two main methods in a Java program?

There can be more than one main method in a single program. Others are Overloaded method. This overloaded method works fine under a single main method

public class MainMultiple{

   public static void main(String args[]){
       main(122);
       main('f');
       main("hello java");
   }

   public static void main(int i){
       System.out.println("Overloaded main()"+i);
   }

   public static void main(char i){
       System.out.println("Overloaded main()"+i);
   }

   public static void main(String str){
       System.out.println("Overloaded main()"+str);
   }
}

How to check if a file is a valid image file?

A lot of times the first couple chars will be a magic number for various file formats. You could check for this in addition to your exception checking above.

How can I use a Python script in the command line without cd-ing to its directory? Is it the PYTHONPATH?

With PYTHONPATH set as in your example, you should be able to do

python -m gmbx

-m option will make Python search for your module in paths Python usually searches modules in, including what you added to PYTHONPATH. When you run interpreter like python gmbx.py, it looks for particular file and PYTHONPATH does not apply.

How to get a list of column names

You can use pragma related commands in sqlite like below

pragma table_info("table_name")
--Alternatively
select * from pragma_table_info("table_name")

If you require column names like id|foo|bar|age|street|address, basically your answer is in below query.

select group_concat(name,'|') from pragma_table_info("table_name")

TypeScript add Object to array with push

class PushObjects {
    testMethod(): Array<number> { 
        //declaration and initialisation of array onject
        var objs: number[] = [1,2,3,4,5,7];
        //push the elements into the array object
        objs.push(100);
        //pop the elements from the array
        objs.pop();
        return objs;
    }   
}

let pushObj = new PushObjects();
//create the button element from the dom object 
let btn = document.createElement('button');
//set the text value of the button
btn.textContent = "Click here";
//button click event
btn.onclick = function () { 

    alert(pushObj.testMethod());

} 

document.body.appendChild(btn);

How to download a file with Node.js (without using third-party libraries)?

Solution with timeout, prevent memory leak :

The following code is based on Brandon Tilley's answer :

var http = require('http'),
    fs = require('fs');

var request = http.get("http://example12345.com/yourfile.html", function(response) {
    if (response.statusCode === 200) {
        var file = fs.createWriteStream("copy.html");
        response.pipe(file);
    }
    // Add timeout.
    request.setTimeout(12000, function () {
        request.abort();
    });
});

Don't make file when you get an error, and prefere to use timeout to close your request after X secondes.

What is the difference between JVM, JDK, JRE & OpenJDK?

JDK: The complete package which you need to write and run java code

OpenJDK: An independent implementation of JDK for making it much better

JVM: Converts Java code into bytecode and provides the specifications which tells how should a Java code be compiled, loaded, verified, checked for errors and executed.

JRE: Implementation of the JVM with which some Java libraries are used to Run the program

New Array from Index Range Swift

This works for me:

var test = [1, 2, 3]
var n = 2
var test2 = test[0..<n]

Your issue could be with how you're declaring your array to begin with.

EDIT:

To fix your function, you have to cast your Slice to an array:

func aFunction(numbers: Array<Int>, position: Int) -> Array<Int> {
    var newNumbers = Array(numbers[0..<position])
    return newNumbers
}

// test
aFunction([1, 2, 3], 2) // returns [1, 2]

How to add a search box with icon to the navbar in Bootstrap 3?

_x000D_
_x000D_
<!DOCTYPE html>_x000D_
<html lang="en">_x000D_
_x000D_
<head>_x000D_
_x000D_
    <meta charset="utf-8">_x000D_
    <meta http-equiv="X-UA-Compatible" content="IE=edge">_x000D_
    <meta name="viewport" content="width=device-width, initial-scale=1">_x000D_
    <meta name="description" content="">_x000D_
    <meta name="author" content="">_x000D_
_x000D_
    <title>3 Col Portfolio - Start Bootstrap Template</title>_x000D_
_x000D_
    <!-- Bootstrap Core CSS -->_x000D_
    <link href="https://maxcdn.bootstrapcdn.com/bootstrap/3.3.6/css/bootstrap.min.css" rel="stylesheet"/>_x000D_
    <!-- HTML5 Shim and Respond.js IE8 support of HTML5 elements and media queries -->_x000D_
    <!-- WARNING: Respond.js doesn't work if you view the page via file:// -->_x000D_
    <!--[if lt IE 9]>_x000D_
        <script src="https://oss.maxcdn.com/libs/html5shiv/3.7.0/html5shiv.js"></script>_x000D_
        <script src="https://oss.maxcdn.com/libs/respond.js/1.4.2/respond.min.js"></script>_x000D_
    <![endif]-->_x000D_
_x000D_
</head>_x000D_
_x000D_
<body>_x000D_
_x000D_
    <!-- Navigation -->_x000D_
    <nav class="navbar navbar-inverse navbar-fixed-top" role="navigation">_x000D_
        <div class="container">_x000D_
            <!-- Brand and toggle get grouped for better mobile display -->_x000D_
            <div class="navbar-header">_x000D_
                <button type="button" class="navbar-toggle" data-toggle="collapse" data-target="#bs-example-navbar-collapse-1">_x000D_
                    <span class="sr-only">Toggle navigation</span>_x000D_
                    <span class="icon-bar"></span>_x000D_
                    <span class="icon-bar"></span>_x000D_
                    <span class="icon-bar"></span>_x000D_
                </button>_x000D_
                <a class="navbar-brand" href="#">Start Bootstrap</a>_x000D_
            </div>_x000D_
            <!-- Collect the nav links, forms, and other content for toggling -->_x000D_
            <div class="collapse navbar-collapse" id="bs-example-navbar-collapse-1">_x000D_
                <ul class="nav navbar-nav">_x000D_
                    <li>_x000D_
                        <a href="#">About</a>_x000D_
                    </li>_x000D_
                    <li>_x000D_
                        <a href="#">Services</a>_x000D_
                    </li>_x000D_
                    <li>_x000D_
                        <a href="#">Contact</a>_x000D_
                    </li>_x000D_
                </ul>_x000D_
                <form class="navbar-form navbar-right">_x000D_
                    <div class="input-group">_x000D_
                        <input type="text" name="keyword" placeholder="search..." class="form-control">_x000D_
                        <span class="input-group-btn">_x000D_
                            <button class="btn btn-default">Go</button>_x000D_
                        </span>_x000D_
                    </div>_x000D_
                </form>_x000D_
            </div>_x000D_
            <!-- /.navbar-collapse -->_x000D_
        </div>_x000D_
        <!-- /.container -->_x000D_
    </nav>_x000D_
_x000D_
    <!-- Page Content -->_x000D_
    <div class="container">_x000D_
_x000D_
        <!-- Page Header -->_x000D_
        <div class="row">_x000D_
            <div class="col-lg-12">_x000D_
                <h1 class="page-header">Page Heading_x000D_
                    <small>Secondary Text</small>_x000D_
                </h1>_x000D_
            </div>_x000D_
        </div>_x000D_
        <!-- /.row -->_x000D_
_x000D_
        <!-- Projects Row -->_x000D_
        <div class="row">_x000D_
            <div class="col-md-3 portfolio-item">_x000D_
                <a href="#">_x000D_
                    <img class="img-responsive" src="http://placehold.it/700x400" alt="">_x000D_
                </a>_x000D_
                <h3>_x000D_
                    <a href="#">Project Name</a>_x000D_
                </h3>_x000D_
                <p>Lorem ipsum dolor sit amet, consectetur adipiscing elit. Nam viverra euismod odio, gravida pellentesque urna varius vitae.</p>_x000D_
            </div>_x000D_
            <div class="col-md-3 portfolio-item">_x000D_
                <a href="#">_x000D_
                    <img class="img-responsive" src="http://placehold.it/700x400" alt="">_x000D_
                </a>_x000D_
                <h3>_x000D_
                    <a href="#">Project Name</a>_x000D_
                </h3>_x000D_
                <p>Lorem ipsum dolor sit amet, consectetur adipiscing elit. Nam viverra euismod odio, gravida pellentesque urna varius vitae.</p>_x000D_
            </div>_x000D_
            <div class="col-md-3 portfolio-item">_x000D_
                <a href="#">_x000D_
                    <img class="img-responsive" src="http://placehold.it/700x400" alt="">_x000D_
                </a>_x000D_
                <h3>_x000D_
                    <a href="#">Project Name</a>_x000D_
                </h3>_x000D_
                <p>Lorem ipsum dolor sit amet, consectetur adipiscing elit. Nam viverra euismod odio, gravida pellentesque urna varius vitae.</p>_x000D_
            </div>_x000D_
            <div class="col-md-3 portfolio-item">_x000D_
                <a href="#">_x000D_
                    <img class="img-responsive" src="http://placehold.it/700x400" alt="">_x000D_
                </a>_x000D_
                <h3>_x000D_
                    <a href="#">Project Name</a>_x000D_
                </h3>_x000D_
                <p>Lorem ipsum dolor sit amet, consectetur adipiscing elit. Nam viverra euismod odio, gravida pellentesque urna varius vitae.</p>_x000D_
            </div>_x000D_
        </div>_x000D_
        <!-- /.row -->_x000D_
_x000D_
        <!-- Projects Row -->_x000D_
        <div class="row">_x000D_
            <div class="col-md-3 portfolio-item">_x000D_
                <a href="#">_x000D_
                    <img class="img-responsive" src="http://placehold.it/700x400" alt="">_x000D_
                </a>_x000D_
                <h3>_x000D_
                    <a href="#">Project Name</a>_x000D_
                </h3>_x000D_
                <p>Lorem ipsum dolor sit amet, consectetur adipiscing elit. Nam viverra euismod odio, gravida pellentesque urna varius vitae.</p>_x000D_
            </div>_x000D_
            <div class="col-md-3 portfolio-item">_x000D_
                <a href="#">_x000D_
                    <img class="img-responsive" src="http://placehold.it/700x400" alt="">_x000D_
                </a>_x000D_
                <h3>_x000D_
                    <a href="#">Project Name</a>_x000D_
                </h3>_x000D_
                <p>Lorem ipsum dolor sit amet, consectetur adipiscing elit. Nam viverra euismod odio, gravida pellentesque urna varius vitae.</p>_x000D_
            </div>_x000D_
            <div class="col-md-3 portfolio-item">_x000D_
                <a href="#">_x000D_
                    <img class="img-responsive" src="http://placehold.it/700x400" alt="">_x000D_
                </a>_x000D_
                <h3>_x000D_
                    <a href="#">Project Name</a>_x000D_
                </h3>_x000D_
                <p>Lorem ipsum dolor sit amet, consectetur adipiscing elit. Nam viverra euismod odio, gravida pellentesque urna varius vitae.</p>_x000D_
            </div>_x000D_
            <div class="col-md-3 portfolio-item">_x000D_
                <a href="#">_x000D_
                    <img class="img-responsive" src="http://placehold.it/700x400" alt="">_x000D_
                </a>_x000D_
                <h3>_x000D_
                    <a href="#">Project Name</a>_x000D_
                </h3>_x000D_
                <p>Lorem ipsum dolor sit amet, consectetur adipiscing elit. Nam viverra euismod odio, gravida pellentesque urna varius vitae.</p>_x000D_
            </div>_x000D_
        </div>_x000D_
        <!-- /.row -->_x000D_
_x000D_
        <!-- Projects Row -->_x000D_
        <div class="row">_x000D_
            <div class="col-md-3 portfolio-item">_x000D_
                <a href="#">_x000D_
                    <img class="img-responsive" src="http://placehold.it/700x400" alt="">_x000D_
                </a>_x000D_
                <h3>_x000D_
                    <a href="#">Project Name</a>_x000D_
                </h3>_x000D_
                <p>Lorem ipsum dolor sit amet, consectetur adipiscing elit. Nam viverra euismod odio, gravida pellentesque urna varius vitae.</p>_x000D_
            </div>_x000D_
            <div class="col-md-3 portfolio-item">_x000D_
                <a href="#">_x000D_
                    <img class="img-responsive" src="http://placehold.it/700x400" alt="">_x000D_
                </a>_x000D_
                <h3>_x000D_
                    <a href="#">Project Name</a>_x000D_
                </h3>_x000D_
                <p>Lorem ipsum dolor sit amet, consectetur adipiscing elit. Nam viverra euismod odio, gravida pellentesque urna varius vitae.</p>_x000D_
            </div>_x000D_
            <div class="col-md-3 portfolio-item">_x000D_
                <a href="#">_x000D_
                    <img class="img-responsive" src="http://placehold.it/700x400" alt="">_x000D_
                </a>_x000D_
                <h3>_x000D_
                    <a href="#">Project Name</a>_x000D_
                </h3>_x000D_
                <p>Lorem ipsum dolor sit amet, consectetur adipiscing elit. Nam viverra euismod odio, gravida pellentesque urna varius vitae.</p>_x000D_
            </div>_x000D_
            <div class="col-md-3 portfolio-item">_x000D_
                <a href="#">_x000D_
                    <img class="img-responsive" src="http://placehold.it/700x400" alt="">_x000D_
                </a>_x000D_
                <h3>_x000D_
                    <a href="#">Project Name</a>_x000D_
                </h3>_x000D_
                <p>Lorem ipsum dolor sit amet, consectetur adipiscing elit. Nam viverra euismod odio, gravida pellentesque urna varius vitae.</p>_x000D_
            </div>_x000D_
        </div>_x000D_
        <!-- /.row -->_x000D_
_x000D_
        <!-- Projects Row -->_x000D_
        <div class="row">_x000D_
            <div class="col-md-3 portfolio-item">_x000D_
                <a href="#">_x000D_
                    <img class="img-responsive" src="http://placehold.it/700x400" alt="">_x000D_
                </a>_x000D_
                <h3>_x000D_
                    <a href="#">Project Name</a>_x000D_
                </h3>_x000D_
                <p>Lorem ipsum dolor sit amet, consectetur adipiscing elit. Nam viverra euismod odio, gravida pellentesque urna varius vitae.</p>_x000D_
            </div>_x000D_
            <div class="col-md-3 portfolio-item">_x000D_
                <a href="#">_x000D_
                    <img class="img-responsive" src="http://placehold.it/700x400" alt="">_x000D_
                </a>_x000D_
                <h3>_x000D_
                    <a href="#">Project Name</a>_x000D_
                </h3>_x000D_
                <p>Lorem ipsum dolor sit amet, consectetur adipiscing elit. Nam viverra euismod odio, gravida pellentesque urna varius vitae.</p>_x000D_
            </div>_x000D_
            <div class="col-md-3 portfolio-item">_x000D_
                <a href="#">_x000D_
                    <img class="img-responsive" src="http://placehold.it/700x400" alt="">_x000D_
                </a>_x000D_
                <h3>_x000D_
                    <a href="#">Project Name</a>_x000D_
                </h3>_x000D_
                <p>Lorem ipsum dolor sit amet, consectetur adipiscing elit. Nam viverra euismod odio, gravida pellentesque urna varius vitae.</p>_x000D_
            </div>_x000D_
            <div class="col-md-3 portfolio-item">_x000D_
                <a href="#">_x000D_
                    <img class="img-responsive" src="http://placehold.it/700x400" alt="">_x000D_
                </a>_x000D_
                <h3>_x000D_
                    <a href="#">Project Name</a>_x000D_
                </h3>_x000D_
                <p>Lorem ipsum dolor sit amet, consectetur adipiscing elit. Nam viverra euismod odio, gravida pellentesque urna varius vitae.</p>_x000D_
            </div>_x000D_
        </div>_x000D_
        <!-- /.row -->_x000D_
_x000D_
        <hr>_x000D_
_x000D_
        <!-- Pagination -->_x000D_
        <div class="row text-center">_x000D_
            <div class="col-lg-12">_x000D_
                <ul class="pagination">_x000D_
                    <li>_x000D_
                        <a href="#">&laquo;</a>_x000D_
                    </li>_x000D_
                    <li class="active">_x000D_
                        <a href="#">1</a>_x000D_
                    </li>_x000D_
                    <li>_x000D_
                        <a href="#">2</a>_x000D_
                    </li>_x000D_
                    <li>_x000D_
                        <a href="#">3</a>_x000D_
                    </li>_x000D_
                    <li>_x000D_
                        <a href="#">4</a>_x000D_
                    </li>_x000D_
                    <li>_x000D_
                        <a href="#">5</a>_x000D_
                    </li>_x000D_
                    <li>_x000D_
                        <a href="#">&raquo;</a>_x000D_
                    </li>_x000D_
                </ul>_x000D_
            </div>_x000D_
        </div>_x000D_
        <!-- /.row -->_x000D_
    </div>_x000D_
    <!-- Footer -->_x000D_
    <footer>_x000D_
        <div class="container">_x000D_
            <div class="row">_x000D_
                <div class="col-lg-4 col-md-4 col-sm-4">_x000D_
                    <h3>About</h3>_x000D_
                    <ul>_x000D_
                        <li>_x000D_
                            <i class="glyphicon glyphicon-home"></i> Your company address here_x000D_
                        </li>_x000D_
                        <li>_x000D_
                            <i class="glyphicon glyphicon-earphone"></i> 0982.808.065_x000D_
                        </li>_x000D_
                        <li>_x000D_
                            <i class="glyphicon glyphicon-envelope"></i> [email protected]_x000D_
                        </li>_x000D_
                        <li>_x000D_
                            <i class="glyphicon glyphicon-flag"></i> <a href="#">Fan page</a>_x000D_
                        </li>_x000D_
                        <li>_x000D_
                            <i class="glyphicon glyphicon-time"></i> 08:00-18:00 Monday to Friday_x000D_
                        </li>_x000D_
                    </ul>_x000D_
                </div>_x000D_
                <div class="col-lg-4 col-md-4 col-sm-4">_x000D_
                    <h3>Support</h3>_x000D_
                    <ul>_x000D_
                        <li>_x000D_
                            <a href="#" class="link">Terms of Service</a>_x000D_
                        </li>_x000D_
                        <li>_x000D_
                            <a href="#" class="link">Privacy policy</a>_x000D_
                        </li>_x000D_
                        <li>_x000D_
                            <a href="#" class="link">Warranty commitment</a>_x000D_
                        </li>_x000D_
                        <li>_x000D_
                            <a href="#" class="link">Site map</a>_x000D_
                        </li>_x000D_
                    </ul>_x000D_
                </div>_x000D_
                <div class="col-lg-4 col-md-4 col-sm-4">_x000D_
                    <h3>Other</h3>_x000D_
                    <p>Lorem ipsum dolor sit amet, consectetur adipisicing elit, sed do eiusmod_x000D_
                    tempor incididunt ut labore et dolore magna aliqua. Ut enim ad minim veniam,_x000D_
                    quis nostrud exercitation ullamco laboris nisi ut aliquip ex ea commodo_x000D_
                    consequat. Duis aute irure dolor in reprehenderit in voluptate velit esse_x000D_
                    cillum dolore eu fugiat nulla pariatur. Excepteur sint occaecat cupidatat non_x000D_
                    proident, sunt in culpa qui officia deserunt mollit anim id est laborum.</p>_x000D_
                </div>_x000D_
            </div>_x000D_
        </div>_x000D_
        <!-- /.row -->_x000D_
    </footer>_x000D_
_x000D_
    <!-- /.container -->_x000D_
_x000D_
    <!-- jQuery -->_x000D_
    <script src="https://ajax.googleapis.com/ajax/libs/jquery/2.1.1/jquery.min.js"></script>_x000D_
_x000D_
    <!-- Bootstrap Core JavaScript -->_x000D_
    <script src="https://maxcdn.bootstrapcdn.com/bootstrap/3.3.6/js/bootstrap.min.js"></script>_x000D_
_x000D_
</body>_x000D_
_x000D_
</html>
_x000D_
_x000D_
_x000D_

Count number of iterations in a foreach loop

Try:

$counter = 0;
foreach ($Contents as $item) {
          something 
          your code  ...
      $counter++;      
}
$total_count=$counter-1;

Best way to store date/time in mongodb

One datestamp is already in the _id object, representing insert time

So if the insert time is what you need, it's already there:

Login to mongodb shell

ubuntu@ip-10-0-1-223:~$ mongo 10.0.1.223
MongoDB shell version: 2.4.9
connecting to: 10.0.1.223/test

Create your database by inserting items

> db.penguins.insert({"penguin": "skipper"})
> db.penguins.insert({"penguin": "kowalski"})
> 

Lets make that database the one we are on now

> use penguins
switched to db penguins

Get the rows back:

> db.penguins.find()
{ "_id" : ObjectId("5498da1bf83a61f58ef6c6d5"), "penguin" : "skipper" }
{ "_id" : ObjectId("5498da28f83a61f58ef6c6d6"), "penguin" : "kowalski" }

Get each row in yyyy-MM-dd HH:mm:ss format:

> db.penguins.find().forEach(function (doc){ d = doc._id.getTimestamp(); print(d.getFullYear()+"-"+(d.getMonth()+1)+"-"+d.getDate() + " " + d.getHours() + ":" + d.getMinutes() + ":" + d.getSeconds()) })
2014-12-23 3:4:41
2014-12-23 3:4:53

If that last one-liner confuses you I have a walkthrough on how that works here: https://stackoverflow.com/a/27613766/445131

Detect network connection type on Android

You can try this:

public String ConnectionQuality() {
    NetworkInfo info = getInfo(context);
    if (info == null || !info.isConnected()) {
      return "UNKNOWN";
    }

    if(info.getType() == ConnectivityManager.TYPE_WIFI) {
        WifiManager wifiManager = (WifiManager) context.getSystemService(Context.WIFI_SERVICE);
        int numberOfLevels = 5;
        WifiInfo wifiInfo = wifiManager.getConnectionInfo();
        int level = WifiManager.calculateSignalLevel(wifiInfo.getRssi(), numberOfLevels);
        if(level == 2 )
                return "POOR";
            else if(level == 3 )
                return "MODERATE";
            else if(level == 4 )
                return "GOOD";
            else if(level == 5 )
                return "EXCELLENT";
            else
            return "UNKNOWN";
        }else if(info.getType() == ConnectivityManager.TYPE_MOBILE) {
            int networkClass = getNetworkClass(getNetworkType(context));
            if(networkClass == 1)
                return "POOR";
            else if(networkClass == 2 )
                return "GOOD";
            else if(networkClass == 3 )
                return "EXCELLENT";
            else
                return "UNKNOWN";
        }else
            return "UNKNOWN";  
}

public NetworkInfo getInfo(Context context) {
    return ((ConnectivityManager) context.getSystemService(Context.CONNECTIVITY_SERVICE)).getActiveNetworkInfo();
}

public int getNetworkClass(int networkType) {
    try {
      return getNetworkClassReflect(networkType);
    }catch (Exception ignored) {
    }

    switch (networkType) {
      case TelephonyManager.NETWORK_TYPE_GPRS:
      case 16: // TelephonyManager.NETWORK_TYPE_GSM:
      case TelephonyManager.NETWORK_TYPE_EDGE:
      case TelephonyManager.NETWORK_TYPE_CDMA:
      case TelephonyManager.NETWORK_TYPE_1xRTT:
      case TelephonyManager.NETWORK_TYPE_IDEN:
        return 1;
      case TelephonyManager.NETWORK_TYPE_UMTS:
      case TelephonyManager.NETWORK_TYPE_EVDO_0:
      case TelephonyManager.NETWORK_TYPE_EVDO_A:
      case TelephonyManager.NETWORK_TYPE_HSDPA:
      case TelephonyManager.NETWORK_TYPE_HSUPA:
      case TelephonyManager.NETWORK_TYPE_HSPA:
      case TelephonyManager.NETWORK_TYPE_EVDO_B:
      case TelephonyManager.NETWORK_TYPE_EHRPD:
      case TelephonyManager.NETWORK_TYPE_HSPAP:
      case 17: // TelephonyManager.NETWORK_TYPE_TD_SCDMA:
        return 2;
      case TelephonyManager.NETWORK_TYPE_LTE:
      case 18: // TelephonyManager.NETWORK_TYPE_IWLAN:
        return 3;
      default:
        return 0;
    }
}

private int getNetworkClassReflect(int networkType) throws NoSuchMethodException, InvocationTargetException, IllegalAccessException {  
    Method getNetworkClass = TelephonyManager.class.getDeclaredMethod("getNetworkClass", int.class);
    if (!getNetworkClass.isAccessible()) {
      getNetworkClass.setAccessible(true);
    }
    return (Integer) getNetworkClass.invoke(null, networkType); 
}

public static int getNetworkType(Context context) {
    return ((TelephonyManager) context.getSystemService(Context.TELEPHONY_SERVICE)).getNetworkType();
}

How to serialize an object to XML without getting xmlns="..."?

Ahh... nevermind. It's always the search after the question is posed that yields the answer. My object that is being serialized is obj and has already been defined. Adding an XMLSerializerNamespace with a single empty namespace to the collection does the trick.

In VB like this:

Dim xs As New XmlSerializer(GetType(cEmploymentDetail))
Dim ns As New XmlSerializerNamespaces()
ns.Add("", "")

Dim settings As New XmlWriterSettings()
settings.OmitXmlDeclaration = True

Using ms As New MemoryStream(), _
    sw As XmlWriter = XmlWriter.Create(ms, settings), _
    sr As New StreamReader(ms)
xs.Serialize(sw, obj, ns)
ms.Position = 0
Console.WriteLine(sr.ReadToEnd())
End Using

in C# like this:

//Create our own namespaces for the output
XmlSerializerNamespaces ns = new XmlSerializerNamespaces();

//Add an empty namespace and empty value
ns.Add("", "");

//Create the serializer
XmlSerializer slz = new XmlSerializer(someType);

//Serialize the object with our own namespaces (notice the overload)
slz.Serialize(myXmlTextWriter, someObject, ns);

GitHub: Permission denied (publickey). fatal: The remote end hung up unexpectedly

after you created the RSA key pair, you must to add it to SSH using:

ssh-add ~/.ssh/id_rsa

or wherever you created your rsa key pair.

How to Make A Chevron Arrow Using CSS?

_x000D_
_x000D_
.arrow {_x000D_
  display : inline-block;_x000D_
  font-size: 10px; /* adjust size */_x000D_
  line-height: 1em; /* adjust vertical positioning */_x000D_
  border: 3px solid #000000;_x000D_
  border-left: transparent;_x000D_
  border-bottom: transparent;_x000D_
  width: 1em; /* use font-size to change overall size */_x000D_
  height: 1em; /* use font-size to change overall size */_x000D_
}_x000D_
_x000D_
.arrow:before {_x000D_
  content: "\00a0"; /* needed to hook line-height to "something" */_x000D_
}_x000D_
_x000D_
.arrow.left {_x000D_
  margin-left: 0.5em;_x000D_
  -webkit-transform: rotate(225deg);_x000D_
  -moz-transform: rotate(225deg);_x000D_
  -o-transform: rotate(225deg);_x000D_
  -ms-transform: rotate(225deg);_x000D_
  transform: rotate(225deg);_x000D_
}_x000D_
_x000D_
.arrow.right {_x000D_
  margin-right: 0.5em;_x000D_
  -webkit-transform: rotate(45deg);_x000D_
  -moz-transform: rotate(45deg);_x000D_
  -o-transform: rotate(45deg);_x000D_
  -ms-transform: rotate(45deg);_x000D_
  transform: rotate(45deg);_x000D_
}_x000D_
_x000D_
.arrow.top {_x000D_
  line-height: 0.5em; /* use this to adjust vertical positioning */_x000D_
  margin-left: 0.5em;_x000D_
  margin-right: 0.5em;_x000D_
  -webkit-transform: rotate(-45deg);_x000D_
  -moz-transform: rotate(-45deg);_x000D_
  -o-transform: rotate(-45deg);_x000D_
  -ms-transform: rotate(-45deg);_x000D_
  transform: rotate(-45deg);_x000D_
}_x000D_
_x000D_
.arrow.bottom {_x000D_
  line-height: 2em;_x000D_
  /* use this to adjust vertical positioning */_x000D_
  margin-left: 0.5em;_x000D_
  margin-right: 0.5em;_x000D_
  -webkit-transform: rotate(135deg);_x000D_
  -moz-transform: rotate(135deg);_x000D_
  -o-transform: rotate(135deg);_x000D_
  -ms-transform: rotate(135deg);_x000D_
  transform: rotate(135deg);_x000D_
}
_x000D_
<div>_x000D_
  here are some arrows_x000D_
  <div class='arrow left'></div> space_x000D_
  <div class='arrow right'></div> space_x000D_
  <div class='arrow top'></div> space_x000D_
  <div class='arrow bottom'></div> space with proper spacing?_x000D_
</div>
_x000D_
_x000D_
_x000D_

Similar to Roko C, but a little more control over size and placement.

Rotating x axis labels in R for barplot

Rotate the x axis labels with angle equal or smaller than 90 degrees using base graphics. Code adapted from the R FAQ:

par(mar = c(7, 4, 2, 2) + 0.2) #add room for the rotated labels

#use mtcars dataset to produce a barplot with qsec colum information
mtcars = mtcars[with(mtcars, order(-qsec)), ] #order mtcars data set by column "qsec"

end_point = 0.5 + nrow(mtcars) + nrow(mtcars) - 1 #this is the line which does the trick (together with barplot "space = 1" parameter)

barplot(mtcars$qsec, col = "grey50", 
        main = "",
        ylab = "mtcars - qsec", ylim = c(0,5 + max(mtcars$qsec)),
        xlab = "",
        space = 1)
#rotate 60 degrees (srt = 60)
text(seq(1.5, end_point, by = 2), par("usr")[3]-0.25, 
     srt = 60, adj = 1, xpd = TRUE,
     labels = paste(rownames(mtcars)), cex = 0.65)

enter image description here

Best way to specify whitespace in a String.Split operation

Why dont you use?:

string[] ssizes = myStr.Split(' ', '\t');

How to change node.js's console font color?

In ubuntu you can simply use color codes:

var sys = require('sys');
process.stdout.write("x1B[31m" + your_message_in_red + "\x1B[0m\r\n");

What is the boundary in multipart/form-data?

multipart/form-data contains boundary to separate name/value pairs. The boundary acts like a marker of each chunk of name/value pairs passed when a form gets submitted. The boundary is automatically added to a content-type of a request header.

The form with enctype="multipart/form-data" attribute will have a request header Content-Type : multipart/form-data; boundary --- WebKit193844043-h (browser generated vaue).

The payload passed looks something like this:

Content-Type: multipart/form-data; boundary=---WebKitFormBoundary7MA4YWxkTrZu0gW

    -----WebKitFormBoundary7MA4YWxkTrZu0gW
    Content-Disposition: form-data; name=”file”; filename=”captcha”
    Content-Type:

    -----WebKitFormBoundary7MA4YWxkTrZu0gW
    Content-Disposition: form-data; name=”action”

    submit
    -----WebKitFormBoundary7MA4YWxkTrZu0gW--

On the webservice side, it's consumed in @Consumes("multipart/form-data") form.

Beware, when testing your webservice using chrome postman, you need to check the form data option(radio button) and File menu from the dropdown box to send attachment. Explicit provision of content-type as multipart/form-data throws an error. Because boundary is missing as it overrides the curl request of post man to server with content-type by appending the boundary which works fine.

See RFC1341 sec7.2 The Multipart Content-Type

how do I join two lists using linq or lambda expressions

The way to do this using the Extention Methods, instead of the linq query syntax would be like this:

var results = workOrders.Join(plans,
  wo => wo.WorkOrderNumber,
  p => p.WorkOrderNumber,
  (order,plan) => new {order.WorkOrderNumber, order.WorkDescription, plan.ScheduledDate}
);

How to correctly use "section" tag in HTML5?

The answer is in the current spec:

The section element represents a generic section of a document or application. A section, in this context, is a thematic grouping of content, typically with a heading.

Examples of sections would be chapters, the various tabbed pages in a tabbed dialog box, or the numbered sections of a thesis. A Web site's home page could be split into sections for an introduction, news items, and contact information.

Authors are encouraged to use the article element instead of the section element when it would make sense to syndicate the contents of the element.

The section element is not a generic container element. When an element is needed for styling purposes or as a convenience for scripting, authors are encouraged to use the div element instead. A general rule is that the section element is appropriate only if the element's contents would be listed explicitly in the document's outline.

Reference:

Also see:

It looks like there's been a lot of confusion about this element's purpose, but the one thing that's agreed upon is that it is not a generic wrapper, like <div> is. It should be used for semantic purposes, and not a CSS or JavaScript hook (although it certainly can be styled or "scripted").

A better example, from my understanding, might look something like this:

<div id="content">
  <article>
     <h2>How to use the section tag</h2>
     <section id="disclaimer">
         <h3>Disclaimer</h3>
         <p>Don't take my word for it...</p>
     </section>
     <section id="examples">
       <h3>Examples</h3>
       <p>But here's how I would do it...</p>
     </section>
     <section id="closing_notes">
       <h3>Closing Notes</h3>
       <p>Well that was fun. I wonder if the spec will change next week?</p>
     </section>
  </article>
</div>

Note that <div>, being completely non-semantic, can be used anywhere in the document that the HTML spec allows it, but is not necessary.

Border length smaller than div width?

You can use pseudoelements. E.g.

_x000D_
_x000D_
div {_x000D_
  width   : 200px;_x000D_
  height  : 50px;   _x000D_
  position: relative;_x000D_
  z-index : 1;_x000D_
  background: #eee;_x000D_
}_x000D_
_x000D_
div:before {_x000D_
  content : "";_x000D_
  position: absolute;_x000D_
  left    : 0;_x000D_
  bottom  : 0;_x000D_
  height  : 1px;_x000D_
  width   : 50%;  /* or 100px */_x000D_
  border-bottom:1px solid magenta;_x000D_
}
_x000D_
<div>Item 1</div>_x000D_
<div>Item 2</div>
_x000D_
_x000D_
_x000D_

No need to use extra markup for presentational purpose. :after is also supported from IE8.

edit:

if you need a right-aligned border, just change left: 0 with right: 0

if you need a center-aligned border just simply set left: 50px;

How to detect duplicate values in PHP array?

Stuff them into a map (pseudocode)

map[string -> int] $m
foreach($word in $array)
{
    if(!$m.contains($word))
        $m[$word] = 0;

    $m[$word] += 1;
}

How do I get Flask to run on port 80?

So it's throwing up that error message because you have apache2 running on port 80.

If this is for development, I would just leave it as it is on port 5000.

If it's for production either:

Not Recommended

  • Stop apache2 first;

Not recommended as it states in the documentation:

You can use the builtin server during development, but you should use a full deployment option for production applications. (Do not use the builtin development server in production.)

Recommended

  • Proxy HTTP traffic through apache2 to Flask.

This way, apache2 can handle all your static files (which it's very good at - much better than the debug server built into Flask) and act as a reverse proxy for your dynamic content, passing those requests to Flask.

Here's a link to the official documentation about setting up Flask with Apache + mod_wsgi.

Edit 1 - Clarification for @Djack

Proxy HTTP traffic to Flask through apache2

When a request comes to the server on port 80 (HTTP) or port 443 (HTTPS) a web server like Apache or Nginx handles the connection of the request and works out what to do with it. In our case a request received should be configured to be passed through to Flask on the WSGI protocol and handled by the Python code. This is the "dynamic" part.

reverse proxy for dynamic content

There are a few advantages to configuring your web server like the above;

  • SSL Termination - The web server will be optimized to handle HTTPS requests with only a little configuration. Don't "roll your own" in Python which is probably very insecure in comparison.
  • Security - Opening a port to the internet requires careful consideration of security. Flask's development server is not designed for this and could have open bugs or security issues in comparison to a web server designed for this purpose. Note that a badly configured web server can also be insecure!
  • Static File Handling - It is possible for the builtin Flask web server to handle static files however this is not recommended; Nginx/Apache are much more efficient at handling static files like images, CSS, Javascript files and will only pass "dynamic" requests (those where the content is often read from a database or the content changes) to be handled by the Python code.
  • +more. This is bordering on scope for this question. If you want more info do some research into this area.

Do we need to execute Commit statement after Update in SQL Server

The SQL Server Management Studio has implicit commit turned on, so all statements that are executed are implicitly commited.

This might be a scary thing if you come from an Oracle background where the default is to not have commands commited automatically, but it's not that much of a problem.

If you still want to use ad-hoc transactions, you can always execute

BEGIN TRANSACTION

within SSMS, and than the system waits for you to commit the data.

If you want to replicate the Oracle behaviour, and start an implicit transaction, whenever some DML/DDL is issued, you can set the SET IMPLICIT_TRANSACTIONS checkbox in

Tools -> Options -> Query Execution -> SQL Server -> ANSI

How many values can be represented with n bits?

The thing you are missing is which encoding scheme is being used. There are different ways to encode binary numbers. Look into signed number representations. For 9 bits, the ranges and the amount of numbers that can be represented will differ depending on the system used.

With CSS, how do I make an image span the full width of the page as a background image?

You set the CSS to :

#elementID {
    background: black url(http://www.electrictoolbox.com/images/rangitoto-3072x200.jpg) center no-repeat;
    height: 200px;
}

It centers the image, but does not scale it.

FIDDLE

In newer browsers you can use the background-size property and do:

#elementID {
    height: 200px; 
    width: 100%;
    background: black url(http://www.electrictoolbox.com/images/rangitoto-3072x200.jpg) no-repeat;
    background-size: 100% 100%;
}

FIDDLE

Other than that, a regular image is one way to do it, but then it's not really a background image.

?

How to change colors of a Drawable in Android?

This works with everything with background:

Textview, Button...

TextView text = (TextView) View.findViewById(R.id.MyText);
text.setBackgroundResource(Icon);    
text.getBackground().setColorFilter(getResources().getColor(Color), PorterDuff.Mode.SRC_ATOP);

What happens if you don't commit a transaction to a database (say, SQL Server)?

When you open a transaction nothing gets locked by itself. But if you execute some queries inside that transaction, depending on the isolation level, some rows, tables or pages get locked so it will affect other queries that try to access them from other transactions.

What is the main difference between PATCH and PUT request?

There are limitations in PUT over PATCH while making updates. Using PUT requires us to specify all attributes even if we want to change only one attribute. But if we use the PATCH method we can update only the fields we need and there is no need to mention all the fields. PATCH does not allow us to modify a value in an array, or remove an attribute or array entry.

How to trigger a click on a link using jQuery

With the code you provided, you cannot expect anything to happen. I second @mashappslabs : first add an event handler :

$("selector").click(function() {
    console.log("element was clicked"); // or alert("click");
});

then trigger your event :

$("selector").click(); //or
$("selector").trigger("click");

and you should see the message in your console.

How to round 0.745 to 0.75 using BigDecimal.ROUND_HALF_UP?

For your interest, to do the same with double

double doubleVal = 1.745;
double doubleVal2 = 0.745;
doubleVal = Math.round(doubleVal * 100 + 0.005) / 100.0;
doubleVal2 = Math.round(doubleVal2 * 100 + 0.005) / 100.0;
System.out.println("bdTest: " + doubleVal); //1.75
System.out.println("bdTest1: " + doubleVal2);//0.75

or just

double doubleVal = 1.745;
double doubleVal2 = 0.745;
System.out.printf("bdTest: %.2f%n",  doubleVal);
System.out.printf("bdTest1: %.2f%n",  doubleVal2);

both print

bdTest: 1.75
bdTest1: 0.75

I prefer to keep code as simple as possible. ;)

As @mshutov notes, you need to add a little more to ensure that a half value always rounds up. This is because numbers like 265.335 are a little less than they appear.

Serializing enums with Jackson

An easy way to serialize Enum is using @JsonFormat annotation. @JsonFormat can configure the serialization of a Enum in three ways.

@JsonFormat.Shape.STRING
public Enum OrderType {...}

uses OrderType::name as the serialization method. Serialization of OrderType.TypeA is “TYPEA”

@JsonFormat.Shape.NUMBER
Public Enum OrderTYpe{...}

uses OrderType::ordinal as the serialization method. Serialization of OrderType.TypeA is 1

@JsonFormat.Shape.OBJECT
Public Enum OrderType{...}

treats OrderType as a POJO. Serialization of OrderType.TypeA is {"id":1,"name":"Type A"}

JsonFormat.Shape.OBJECT is what you need in your case.

A little more complicated way is your solution, specifying a serializer for the Enum.

Check out this reference: https://fasterxml.github.io/jackson-annotations/javadoc/2.2.0/com/fasterxml/jackson/annotation/JsonFormat.html

How do I rotate the Android emulator display?

Make sure that "Auto Rotate" on your Android settings is enabled

Press F9 two times in less than 2 seconds = Normal view 0/360º

Press F10 two times in less than 2 seconds = Rotate 180º.

Press F11 two times in less than 2 seconds = Rotate 90º to the RiGHT.

Press F12 two times in less than 2 seconds = Rotate 90º to the LEFT.

Update Jenkins from a war file

Mine is installed under /usr/share/jenkins I thought it was installed via apt-get so might want to check there as well.

Ubuntu 12.04.1

Is it ok to run docker from inside docker?

It's OK to run Docker-in-Docker (DinD) and in fact Docker (the company) has an official DinD image for this.

The caveat however is that it requires a privileged container, which depending on your security needs may not be a viable alternative.

The alternative solution of running Docker using sibling containers (aka Docker-out-of-Docker or DooD) does not require a privileged container, but has a few drawbacks that stem from the fact that you are launching the container from within a context that is different from that one in which it's running (i.e., you launch the container from within a container, yet it's running at the host's level, not inside the container).

I wrote a blog describing the pros/cons of DinD vs DooD here.

Having said this, Nestybox (a startup I just founded) is working on a solution that runs true Docker-in-Docker securely (without using privileged containers). You can check it out at www.nestybox.com.

Java Webservice Client (Best way)

You can find some resources related to developing web services client using Apache axis2 here.

http://today.java.net/pub/a/today/2006/12/13/invoking-web-services-using-apache-axis2.html

Below posts gives good explanations about developing web services using Apache axis2.

http://www.ibm.com/developerworks/opensource/library/ws-webaxis1/

http://wso2.org/library/136

Adding double quote delimiters into csv file

Double quotes can be achieved using VBA in one of two ways

First one is often the best

"...text..." & Chr(34) & "...text..."

Or the second one, which is more literal

"...text..." & """" & "...text..."

Django template how to look up a dictionary value with a variable

For me creating a python file named template_filters.py in my App with below content did the job

# coding=utf-8
from django.template.base import Library

register = Library()


@register.filter
def get_item(dictionary, key):
    return dictionary.get(key)

usage is like what culebrón said :

{{ mydict|get_item:item.NAME }}

Calculate Pandas DataFrame Time Difference Between Two Columns in Hours and Minutes

This was driving me bonkers as the .astype() solution above didn't work for me. But I found another way. Haven't timed it or anything, but might work for others out there:

t1 = pd.to_datetime('1/1/2015 01:00')
t2 = pd.to_datetime('1/1/2015 03:30')

print pd.Timedelta(t2 - t1).seconds / 3600.0

...if you want hours. Or:

print pd.Timedelta(t2 - t1).seconds / 60.0

...if you want minutes.

A simple command line to download a remote maven2 artifact to the local repository?

Give them a trivial pom with these jars listed as dependencies and instructions to run:

mvn dependency:go-offline

This will pull the dependencies to the local repo.

A more direct solution is dependency:get, but it's a lot of arguments to type:

mvn dependency:get -DrepoUrl=something -Dartifact=group:artifact:version

httpd Server not started: (13)Permission denied: make_sock: could not bind to address [::]:88

Seems like you are running it not as "root". Only root can bind to this port (80). Check your configuration in the conf/httpd.conf file, Listen line and change the port to higher one.

Angular 2 - How to navigate to another route using this.router.parent.navigate('/about')?

Absolute path routing

There are 2 methods for navigation, .navigate() and .navigateByUrl()

You can use the method .navigateByUrl() for absolute path routing:

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

constructor(private router: Router) {}

navigateToLogin() {
   this.router.navigateByUrl('/login');
}

You put the absolute path to the URL of the component you want to navigate to.

Note: Always specify the complete absolute path when calling router's navigateByUrl method. Absolute paths must start with a leading /

// Absolute route - Goes up to root level    
this.router.navigate(['/root/child/child']);

// Absolute route - Goes up to root level with route params   
this.router.navigate(['/root/child', crisis.id]);

Relative path routing

If you want to use relative path routing, use the .navigate() method.

NOTE: It's a little unintuitive how the routing works, particularly parent, sibling, and child routes:

// Parent route - Goes up one level 
// (notice the how it seems like you're going up 2 levels)
this.router.navigate(['../../parent'], { relativeTo: this.route });

// Sibling route - Stays at the current level and moves laterally, 
// (looks like up to parent then down to sibling)
this.router.navigate(['../sibling'], { relativeTo: this.route });

// Child route - Moves down one level
this.router.navigate(['./child'], { relativeTo: this.route });

// Moves laterally, and also add route parameters
// if you are at the root and crisis.id = 15, will result in '/sibling/15'
this.router.navigate(['../sibling', crisis.id], { relativeTo: this.route });

// Moves laterally, and also add multiple route parameters
// will result in '/sibling;id=15;foo=foo'. 
// Note: this does not produce query string URL notation with ? and & ... instead it
// produces a matrix URL notation, an alternative way to pass parameters in a URL.
this.router.navigate(['../sibling', { id: crisis.id, foo: 'foo' }], { relativeTo: this.route });

Or if you just need to navigate within the current route path, but to a different route parameter:

// If crisis.id has a value of '15'
// This will take you from `/hero` to `/hero/15`
this.router.navigate([crisis.id], { relativeTo: this.route });

Link parameters array

A link parameters array holds the following ingredients for router navigation:

  • The path of the route to the destination component. ['/hero']
  • Required and optional route parameters that go into the route URL. ['/hero', hero.id] or ['/hero', { id: hero.id, foo: baa }]

Directory-like syntax

The router supports directory-like syntax in a link parameters list to help guide route name lookup:

./ or no leading slash is relative to the current level.

../ to go up one level in the route path.

You can combine relative navigation syntax with an ancestor path. If you must navigate to a sibling route, you could use the ../<sibling> convention to go up one level, then over and down the sibling route path.

Important notes about relative nagivation

To navigate a relative path with the Router.navigate method, you must supply the ActivatedRoute to give the router knowledge of where you are in the current route tree.

After the link parameters array, add an object with a relativeTo property set to the ActivatedRoute. The router then calculates the target URL based on the active route's location.

From official Angular Router Documentation

how to check the jdk version used to compile a .class file

Does the -verbose flag to your java command yield any useful info? If not, maybe java -X reveals something specific to your version that might help?

How to use SVG markers in Google Maps API v3

You need to pass optimized: false.

E.g.

var img = { url: 'img/puff.svg', scaledSide: new google.maps.Size(5, 5) };
new google.maps.Marker({position: this.mapOptions.center, map: this.map, icon: img, optimized: false,});

Without passing optimized: false, my svg appeared as a static image.

How to remove certain characters from a string in C++?

Here's yet another alternative:

template<typename T>
void Remove( std::basic_string<T> & Str, const T * CharsToRemove )
{
    std::basic_string<T>::size_type pos = 0;
    while (( pos = Str.find_first_of( CharsToRemove, pos )) != std::basic_string<T>::npos )
    {
        Str.erase( pos, 1 ); 
    }
}

std::string a ("(555) 555-5555");
Remove( a, "()-");

Works with std::string and std::wstring

border-radius not working

For my case, I have a dropdown list in my div container, so I can not use overflow: hidden or my dropdown list will be hidden.

Inspired by this discussion: https://twitter.com/siddharthkp/status/1094821277452234752 I use border-bottom-left-radius and border-bottom-right-radius in the child element to fix this issue.

make sure you add it the correct value for each child separately

enter image description here

How to execute a shell script from C in Linux?

I prefer fork + execlp for "more fine-grade" control as doron mentioned. Example code shown below.

Store you command in a char array parameters, and malloc space for the result.

int fd[2];
pipe(fd);
if ( (childpid = fork() ) == -1){
   fprintf(stderr, "FORK failed");
   return 1;
} else if( childpid == 0) {
   close(1);
   dup2(fd[1], 1);
   close(fd[0]);
   execlp("/bin/sh","/bin/sh","-c",parameters,NULL);
}
wait(NULL);
read(fd[0], result, RESULT_SIZE);
printf("%s\n",result);

Selecting last element in JavaScript array

Underscore and Lodash have the _.last(Array) method, that returns the last element in an Array. They both work about the same

_.last([5, 4, 3, 2, 1]);
=> 1

Ramda also has a _.last function

R.last(['fi', 'fo', 'fum']); //=> 'fum'

Windows CMD command for accessing usb?

Try this batch :

@echo off
Title List of connected external devices by Hackoo
Mode con cols=100 lines=20 & Color 9E
wmic LOGICALDISK where driveType=2 get deviceID > wmic.txt
for /f "skip=1" %%b IN ('type wmic.txt') DO (echo %%b & pause & Dir %%b)
Del wmic.txt
pause

how do I insert a column at a specific column index in pandas?

You could try to extract columns as list, massage this as you want, and reindex your dataframe:

>>> cols = df.columns.tolist()
>>> cols = [cols[-1]]+cols[:-1] # or whatever change you need
>>> df.reindex(columns=cols)

   n  l  v
0  0  a  1
1  0  b  2
2  0  c  1
3  0  d  2

EDIT: this can be done in one line ; however, this looks a bit ugly. Maybe some cleaner proposal may come...

>>> df.reindex(columns=['n']+df.columns[:-1].tolist())

   n  l  v
0  0  a  1
1  0  b  2
2  0  c  1
3  0  d  2

Prepare for Segue in Swift

This seems to be due to a problem in the UITableViewController subclass template. It comes with a version of the prepareForSegue method that would require you to unwrap the segue.

Replace your current prepareForSegue function with:

override func prepareForSegue(segue: UIStoryboardSegue!, sender: AnyObject!) {
    if (segue.identifier == "Load View") {
        // pass data to next view
    }
}

This version implicitly unwraps the parameters, so you should be fine.

Correct way to work with vector of arrays

You cannot store arrays in a vector or any other container. The type of the elements to be stored in a container (called the container's value type) must be both copy constructible and assignable. Arrays are neither.

You can, however, use an array class template, like the one provided by Boost, TR1, and C++0x:

std::vector<std::array<double, 4> >

(You'll want to replace std::array with std::tr1::array to use the template included in C++ TR1, or boost::array to use the template from the Boost libraries. Alternatively, you can write your own; it's quite straightforward.)

What is the difference between BIT and TINYINT in MySQL?

From my experience I'm telling you that BIT has problems on linux OS types(Ubuntu for ex). I developped my db on windows and after I deployed everything on linux, I had problems with queries that inserted or selected from tables that had BIT DATA TYPE.

Bit is not safe for now. I changed to tinyint(1) and worked perfectly. I mean that you only need a value to diferentiate if it's 1 or 0 and tinyint(1) it's ok for that

XCOPY switch to create specified directory if it doesn't exist?

I tried this on the command line using

D:\>xcopy myfile.dat xcopytest\test\

and the target directory was properly created.

If not you can create the target dir using the mkdir command with cmd's command extensions enabled like

cmd /x /c mkdir "$(SolutionDir)Prism4Demo.Shell\$(OutDir)Modules\"

('/x' enables command extensions in case they're not enabled by default on your system, I'm not that familiar with cmd)

use

cmd /? 
mkdir /?
xcopy /?

for further information :)

"OSError: [Errno 1] Operation not permitted" when installing Scrapy in OSX 10.11 (El Capitan) (System Integrity Protection)

I was missing a dependency somewhere else along the line, so I installed the other requirements for the project like this:

pip install --user -r requirements.txt

ORA-01008: not all variables bound. They are bound

The solution in my situation was similar answer to Charles Burns; and the problem was related to SQL code comments.

I was building (or updating, rather) an already-functioning SSRS report with Oracle datasource. I added some more parameters to the report, tested it in Visual Studio, it works great, so I deployed it to the report server, and then when the report is executed the report on the server I got the error message:

"ORA-01008: not all variables bound"

I tried quite a few different things (TNSNames.ora file installed on the server, Removed single line comments, Validate dataset query mapping). What it came down to was I had to remove a comment block directly after the WHERE keyword. The error message was resolved after moving the comment block after the WHERE CLAUSE conditions. I have other comments in the code also. It was just the one after the WHERE keyword causing the error.

SQL with error: "ORA-01008: not all variables bound"...

WHERE
/*
    OHH.SHIP_DATE BETWEEN TO_DATE('10/1/2018', 'MM/DD/YYYY') AND TO_DATE('10/31/2018', 'MM/DD/YYYY')
    AND OHH.STATUS_CODE<>'DL'
    AND OHH.BILL_COMP_CODE=100
    AND OHH.MASTER_ORDER_NBR IS NULL
*/

    OHH.SHIP_DATE BETWEEN :paramStartDate AND :paramEndDate
    AND OHH.STATUS_CODE<>'DL'
    AND OHH.BILL_COMP_CODE IN (:paramCompany)
    AND LOAD.DEPART_FROM_WHSE_CODE IN (:paramWarehouse) 
    AND OHH.MASTER_ORDER_NBR IS NULL
    AND LOAD.CLASS_CODE IN (:paramClassCode) 
    AND CUST.CUST_CODE || '-' || CUST.CUST_SHIPTO_CODE IN (:paramShipto) 

SQL executes successfully on the report server...

WHERE
    OHH.SHIP_DATE BETWEEN :paramStartDate AND :paramEndDate
    AND OHH.STATUS_CODE<>'DL'
    AND OHH.BILL_COMP_CODE IN (:paramCompany)
    AND LOAD.DEPART_FROM_WHSE_CODE IN (:paramWarehouse) 
    AND OHH.MASTER_ORDER_NBR IS NULL
    AND LOAD.CLASS_CODE IN (:paramClassCode) 
    AND CUST.CUST_CODE || '-' || CUST.CUST_SHIPTO_CODE IN (:paramShipto)   
/*
    OHH.SHIP_DATE BETWEEN TO_DATE('10/1/2018', 'MM/DD/YYYY') AND TO_DATE('10/31/2018', 'MM/DD/YYYY')
    AND OHH.STATUS_CODE<>'DL'
    AND OHH.BILL_COMP_CODE=100
    AND OHH.MASTER_ORDER_NBR IS NULL
*/

Here is what the dataset parameter mapping screen looks like.

enter image description here

What's the fastest way to convert String to Number in JavaScript?

Here is simple way to do it: var num = Number(str); in this example str is the variable that contains the string. You can tested and see how it works open: Google chrome developer tools, then go to the console and paste the following code. read the comments to understand better how the conversion is done.

// Here Im creating my variable as a string
var str = "258";


// here im printing the string variable: str
console.log ( str );


// here Im using typeof , this tells me that the variable str is the type: string
console.log ("The variable str is type: " + typeof str);


// here is where the conversion happens
// Number will take the string in the parentesis and transform it to a variable num as type: number
var num = Number(str);
console.log ("The variable num is type: " + typeof num);

Forward slash in Java Regex

Double escaping is required when presented as a string.

Whenever I'm making a new regular expression I do a bunch of tests with online tools, for example: http://www.regexplanet.com/advanced/java/index.html

That website allows you to enter the regular expression, which it'll escape into a string for you, and you can then test it against different inputs.

Get all unique values in a JavaScript array (remove duplicates)

_x000D_
_x000D_
(function() {_x000D_
    "use strict";_x000D_
_x000D_
    Array.prototype.unique = function unique() {_x000D_
        var self = this;_x000D_
        return self.filter(function(a) {_x000D_
            var that = this;_x000D_
            // console.log(that);_x000D_
            return !that[a] ? that[a] = true : false;_x000D_
        }, {});_x000D_
    }_x000D_
_x000D_
    var sampleArray = [0, 1, 2, 3, 4, 5, 6, 7, 8, 9, 0, 1, 2, 3, 4, 5, 6, 7, 8, 9];_x000D_
    var distinctArray = sampleArray.unique();_x000D_
    console.log(distinctArray);_x000D_
})();
_x000D_
Here is the simple way to solve this problem...
_x000D_
_x000D_
_x000D_

Setting Curl's Timeout in PHP

There is a quirk with this that might be relevant for some people... From the PHP docs comments.

If you want cURL to timeout in less than one second, you can use CURLOPT_TIMEOUT_MS, although there is a bug/"feature" on "Unix-like systems" that causes libcurl to timeout immediately if the value is < 1000 ms with the error "cURL Error (28): Timeout was reached". The explanation for this behavior is:

"If libcurl is built to use the standard system name resolver, that portion of the transfer will still use full-second resolution for timeouts with a minimum timeout allowed of one second."

What this means to PHP developers is "You can't use this function without testing it first, because you can't tell if libcurl is using the standard system name resolver (but you can be pretty sure it is)"

The problem is that on (Li|U)nix, when libcurl uses the standard name resolver, a SIGALRM is raised during name resolution which libcurl thinks is the timeout alarm.

The solution is to disable signals using CURLOPT_NOSIGNAL. Here's an example script that requests itself causing a 10-second delay so you can test timeouts:

if (!isset($_GET['foo'])) {
    // Client
    $ch = curl_init('http://localhost/test/test_timeout.php?foo=bar');
    curl_setopt($ch, CURLOPT_RETURNTRANSFER, true);
    curl_setopt($ch, CURLOPT_NOSIGNAL, 1);
    curl_setopt($ch, CURLOPT_TIMEOUT_MS, 200);
    $data = curl_exec($ch);
    $curl_errno = curl_errno($ch);
    $curl_error = curl_error($ch);
    curl_close($ch);

    if ($curl_errno > 0) {
        echo "cURL Error ($curl_errno): $curl_error\n";
    } else {
        echo "Data received: $data\n";
    }
} else {
    // Server
    sleep(10);
    echo "Done.";
}

From http://www.php.net/manual/en/function.curl-setopt.php#104597

How can I disable an <option> in a <select> based on its value in JavaScript?

You can also use this function,

function optionDisable(selectId, optionIndices)
{
    for (var idxCount=0; idxCount<optionIndices.length;idxCount++)
    {
        document.getElementById(selectId).children[optionIndices[idxCount]].disabled="disabled";
        document.getElementById(selectId).children[optionIndices[idxCount]].style.backgroundColor = '#ccc';
        document.getElementById(selectId).children[optionIndices[idxCount]].style.color = '#f00';
    }
}

Hiding button using jQuery

You can use the .hide() function bound to a click handler:

$('#Comanda').click(function() {
    $(this).hide();
});

possibly undefined macro: AC_MSG_ERROR

There are two possible reasons for that problem:

  1. did not install aclocal.
    solution:install libtool

    • For ubuntu: sudo apt-get install libtool
    • For centos: sudo yum install libtool
  2. the path to LIBTOOL.m4 is error.
    solution:

    1. use aclocal --print-ac-dir to check current path to aclocal.(It's usually should be "/usr/share/aclocal" or "/usr/share/aclocal")
    2. Then check if there are *.m4 files.
    3. If not, cp corresponding *.m4 files to this path.( Maybe cp /usr/share/aclocal/*.m4 /usr/local/share/aclocal/ or cp /usr/local/share/aclocal/*.m4 /usr/share/aclocal/)

Hope it helps

How to extract the first two characters of a string in shell scripting?

Just grep:

echo 'abcdef' | grep -Po "^.."        # ab

Filter an array using a formula (without VBA)

Today, in Office 365, Excel has so called 'array functions'. The filter function does exactly what you want. No need to use CTRL+SHIFT+ENTER anymore, a simple enter will suffice.

In Office 365, your problem would be simply solved by using:

=VLOOKUP(A3, FILTER(A2:C6, B2:B6="B"), 3, FALSE)

Appending to an empty DataFrame in Pandas?

And if you want to add a row, you can use a dictionary:

df = pd.DataFrame()
df = df.append({'name': 'Zed', 'age': 9, 'height': 2}, ignore_index=True)

which gives you:

   age  height name
0    9       2  Zed

How do I disable form fields using CSS?

This can be helpful:

<input type="text" name="username" value="admin" >

<style type="text/css">
input[name=username] {
    pointer-events: none;
 }
</style>

Update:

and if want to disable from tab index you can use it this way:

 <input type="text" name="username" value="admin" tabindex="-1" >

 <style type="text/css">
  input[name=username] {
    pointer-events: none;
   }
 </style>

Load jQuery with Javascript and use jQuery

There's a working JSFiddle with a small example here, that demonstrates exactly what you are looking for (unless I've misunderstood your request): http://jsfiddle.net/9N7Z2/188/

There are a few issues with that method of loading javascript dynamically. When it comes to the very basal frameworks, like jQuery, you actually probably want to load them statically, because otherwise, you would have to write a whole JavaScript loading framework...

You could use some of the existing JavaScript loaders, or write your own by watching for window.jQuery to get defined.

// Immediately-invoked function expression
(function() {
    // Load the script
    var script = document.createElement("SCRIPT");
    script.src = 'https://ajax.googleapis.com/ajax/libs/jquery/1.7.1/jquery.min.js';
    script.type = 'text/javascript';
    script.onload = function() {
        var $ = window.jQuery;
        // Use $ here...
    };
    document.getElementsByTagName("head")[0].appendChild(script);
})();

Just remember that if you need to support really old browsers, like IE8, load event handlers do not execute. In that case, you would need to poll for the existance of window.jQuery using repeated window.setTimeout. There is a working JSFiddle with that method here: http://jsfiddle.net/9N7Z2/3/

There are lots of people who have already done what you need to do. Check out some of the existing JavaScript Loader frameworks, like:

Read/Write String from/to a File in Android

I'm a bit of a beginner and struggled getting this to work today.

Below is the class that I ended up with. It works but I was wondering how imperfect my solution is. Anyway, I was hoping some of you more experienced folk might be willing to have a look at my IO class and give me some tips. Cheers!

public class HighScore {
    File data = new File(Environment.getExternalStorageDirectory().getAbsolutePath() + File.separator);
    File file = new File(data, "highscore.txt");
    private int highScore = 0;

    public int readHighScore() {
        try {
            BufferedReader br = new BufferedReader(new FileReader(file));
            try {
                highScore = Integer.parseInt(br.readLine());
                br.close();
            } catch (NumberFormatException | IOException e) {
                e.printStackTrace();
            }
        } catch (FileNotFoundException e) {
            try {
                file.createNewFile();
            } catch (IOException ioe) {
                ioe.printStackTrace();
            }
            e.printStackTrace();
        }
        return highScore;
    }

    public void writeHighScore(int highestScore) {
        try {
            BufferedWriter bw = new BufferedWriter(new FileWriter(file));
            bw.write(String.valueOf(highestScore));
            bw.close();
        } catch (IOException e) {
            e.printStackTrace();
        }
    }
}

Php header location redirect not working

Neer to specify exit code here so php not execute further

if ((isset($_POST['cancel'])) && ($_POST['cancel'] == 'cancel'))
{
    header('Location: page1.php');        
    exit(0); // require to exit here 
}

Mongodb find() query : return only unique values (no duplicates)

I think you can use db.collection.distinct(fields,query)

You will be able to get the distinct values in your case for NetworkID.

It should be something like this :

Db.collection.distinct('NetworkID')

Make footer stick to bottom of page correctly

Use this one. It will fix it.

#ibox_footer {
    padding-top: 3px; 
    position: absolute;
    height: 20px;
    margin-bottom: 0;
    bottom: 0;
    width: 100%;
}

Avoid printStackTrace(); use a logger call instead

The main reason is that Proguard would remove Log calls from production. Because by logging or printing StackTrace, it is possible to see them (information inside stack trace or Log) inside the Android phone by for example Logcat Reader application. So that it is a bad practice for security. Also, we do not access them during production, it would better to get removed from production. As ProGuard remove all Log calls not stackTrace, so it is better to use Log in catch blocks and let them removed from Production by Proguard.

php convert datetime to UTC

try

echo date('F d Y', strtotime('2010-01-19 00:00:00'));

will output:

January 19 2010

you should change format time to see other output

iPhone 6 Plus resolution confusion: Xcode or Apple's website? for development

The answer is that older apps run in 2208 x 1242 Zoomed Mode. But when an app is built for the new phones the resolutions available are: Super Retina HD 5.8 (iPhone X) 1125 x 2436 (458ppi), Retina HD 5.5 (iPhone 6, 7, 8 Plus) 1242 x 2208 and Retina HD 4.7 (iPhone 6) 750 x 1334. This is causing the confusion mentioned in the question. To build apps that use the full screen size of the new phones add LaunchImages in the sizes: 1125 x 2436, 1242 x 2208, 2208 x 1242 and 750 x 1334.


Updated for the new iPhones 12, 12 mini, 12 Pro, 12 Pro Max

Size for iPhone 12 Pro Max with @3x scaling, coordinate space: 428 x 926 points and 1284 x 2778 pixels, 458 ppi, device physical size is 3.07 x 6.33 in or 78.1 x 160.8 mm. 6.7" Super Retina XDR display.

Size for iPhone 12 Pro with @3x scaling, coordinate space: 390 x 844 points and 1170 x 2532 pixels, 460 ppi, device physical size is 2.82 x 5.78 in or 71.5 x 146.7 mm. 6.1" Super Retina XDR display.

Size for iPhone 12 with @2x scaling, coordinate space: 585 x 1266 points and 1170 x 2532 pixels, 460 ppi, device physical size is 2.82 x 5.78 in or 71.5 x 146.7 mm. 6.1" Super Retina XDR display.

Size for iPhone 12 mini with @2x scaling, coordinate space: 540 x 1170 points and 1080 x 2340 pixels, 476 ppi, device physical size is 2.53 x 5.18 in or 64.2 x 131.5 mm. 5.4" Super Retina XDR display.


Size for iPhone 11 Pro Max with @3x scaling, coordinate space: 414 x 896 points and 1242 x 2688 pixels, 458 ppi, device physical size is 3.06 x 6.22 in or 77.8 x 158.0 mm. 6.5" Super Retina XDR display.

Size for iPhone 11 Pro with @3x scaling, coordinate space: 375 x 812 points and 1125 x 2436 pixels, 458 ppi, device physical size is 2.81 x 5.67 in or 71.4 x 144.0 mm. 5.8" Super Retina XDR display.

Size for iPhone 11 with @2x scaling, coordinate space: 414 x 896 points and 828 x 1792 pixels, 326 ppi, device physical size is 2.98 x 5.94 in or 75.7 x 150.9 mm. 6.1" Liquid Retina HD display.

Size for iPhone X Max with @3x scaling (Apple name: Super Retina HD 6.5 display"), coordinate space: 414 x 896 points and 1242 x 2688 pixels, 458 ppi, device physical size is 3.05 x 6.20 in or 77.4 x 157.5 mm.

let screen = UIScreen.main
print("Screen bounds: \(screen.bounds), Screen resolution: \(screen.nativeBounds), scale: \(screen.scale)")
//iPhone X Max Screen bounds: (0.0, 0.0, 414.0, 896.0), Screen resolution: (0.0, 0.0, 1242.0, 2688.0), scale: 3.0

Size for iPhone X with @2x scaling (Apple name: Super Retina HD 6.1" display), coordinate space: 414 x 896 points and 828 x 1792 pixels, 326 ppi, device physical size is 2.98 x 5.94 in or 75.7 x 150.9 mm.

let screen = UIScreen.main
print("Screen bounds: \(screen.bounds), Screen resolution: \(screen.nativeBounds), scale: \(screen.scale)")
//iPhone X Screen bounds: (0.0, 0.0, 414.0, 896.0), Screen resolution: (0.0, 0.0, 828.0, 1792.0), scale: 2.0

Size for iPhone X and iPhone X with @3x scaling (Apple name: Super Retina HD 5.8" display), coordinate space: 375 x 812 points and 1125 x 2436 pixels, 458 ppi, device physical size is 2.79 x 5.65 in or 70.9 x 143.6 mm.

let screen = UIScreen.main
print("Screen bounds: \(screen.bounds), Screen resolution: \(screen.nativeBounds), scale: \(screen.scale)")
//iPhone X and X Screen bounds: (0.0, 0.0, 375.0, 812.0), Screen resolution: (0.0, 0.0, 1125.0, 2436.0), scale: 3.0

enter image description here

Size for iPhone 6, 6S, 7 and 8 with @3x scaling (Apple name: Retina HD 5.5), coordinate space: 414 x 736 points and 1242 x 2208 pixels, 401 ppi, screen physical size is 2.7 x 4.8 in or 68 x 122 mm. When running in Zoomed Mode, i.e. without the new LaunchImages or choosen in Setup on iPhone 6 Plus, the native scale is 2.88 and the screen is 320 x 568 points, which is the iPhone 5 native size:

Screen bounds: {{0, 0}, {414, 736}}, Screen resolution: <UIScreen: 0x7f97fad330b0; bounds = {{0, 0}, {414, 736}};
mode = <UIScreenMode: 0x7f97fae1ce00; size = 1242.000000 x 2208.000000>>, scale: 3.000000, nativeScale: 3.000000

Size for iPhone 6 and iPhone 6S with @2x scaling (Apple name: Retina HD 4.7), coordinate space: 375 x 667 points and 750 x 1334 pixels, 326 ppi, screen physical size is 2.3 x 4.1 in or 58 x 104 mm. When running in Zoomed Mode, i.e. without the new LaunchImages, the screen is 320 x 568 points, which is the iPhone 5 native size:

Screen bounds: {{0, 0}, {375, 667}}, Screen resolution: <UIScreen: 0x7fa01b5182d0; bounds = {{0, 0}, {375, 667}};
mode = <UIScreenMode: 0x7fa01b711760; size = 750.000000 x 1334.000000>>, scale: 2.000000, nativeScale: 2.000000

And iPhone 5 for comparison is 640 x 1136, iPhone 4 640 x 960.


Here is the code I used to check this out (note that nativeScale only runs on iOS 8):

UIScreen *mainScreen = [UIScreen mainScreen];
NSLog(@"Screen bounds: %@, Screen resolution: %@, scale: %f, nativeScale: %f",
          NSStringFromCGRect(mainScreen.bounds), mainScreen.coordinateSpace, mainScreen.scale, mainScreen.nativeScale);

Note: Upload LaunchImages otherwise the app will run in Zoomed Mode and not show the correct scaling, or screen sizes. In Zoomed Mode the nativeScale and scale will not be the same. On an actual device the scale can be 2.608 on the iPhone 6 Plus, even when it is not running in Zoomed Mode, but it will show scale of 3.0 when running on the simulator.

Comparing iPhone 6 and 6 Plus

Hexadecimal To Decimal in Shell Script

The error as reported appears when the variables are null (or empty):

$ unset var3 var4; var5=$(($var4-$var3))
bash: -: syntax error: operand expected (error token is "-")

That could happen because the value given to bc was incorrect. That might well be that bc needs UPPERcase values. It needs BFCA3000, not bfca3000. That is easily fixed in bash, just use the ^^ expansion:

var3=bfca3000; var3=`echo "ibase=16; ${var1^^}" | bc`

That will change the script to this:

#!/bin/bash

var1="bfca3000"
var2="efca3250"

var3="$(echo "ibase=16; ${var1^^}" | bc)"
var4="$(echo "ibase=16; ${var2^^}" | bc)"

var5="$(($var4-$var3))"

echo "Diference $var5"

But there is no need to use bc [1], as bash could perform the translation and substraction directly:

#!/bin/bash

var1="bfca3000"
var2="efca3250"

var5="$(( 16#$var2 - 16#$var1 ))"

echo "Diference $var5"

[1]Note: I am assuming the values could be represented in 64 bit math, as the difference was calculated in bash in your original script. Bash is limited to integers less than ((2**63)-1) if compiled in 64 bits. That will be the only difference with bc which does not have such limit.

How to serialize a JObject without the formatting?

Call JObject's ToString(Formatting.None) method.

Alternatively if you pass the object to the JsonConvert.SerializeObject method it will return the JSON without formatting.

Documentation: Write JSON text with JToken.ToString

Correct way to integrate jQuery plugins in AngularJS

i have alreay 2 situations where directives and services/factories didnt play well.

the scenario is that i have (had) a directive that has dependency injection of a service, and from the directive i ask the service to make an ajax call (with $http).

in the end, in both cases the ng-Repeat did not file at all, even when i gave the array an initial value.

i even tried to make a directive with a controller and an isolated-scope

only when i moved everything to a controller and it worked like magic.

example about this here Initialising jQuery plugin (RoyalSlider) in Angular JS

Converting list to numpy array

If you have a list of lists, you only needed to use ...

import numpy as np
...
npa = np.asarray(someListOfLists, dtype=np.float32)

per this LINK in the scipy / numpy documentation. You just needed to define dtype inside the call to asarray.

How to do an INNER JOIN on multiple columns

If you want to search on both FROM and TO airports, you'll want to join on the Airports table twice - then you can use both from and to tables in your results set:

SELECT
   Flights.*,fromAirports.*,toAirports.*
FROM
   Flights
INNER JOIN 
   Airports fromAirports on Flights.fairport = fromAirports.code
INNER JOIN 
   Airports toAirports on Flights.tairport = toAirports.code
WHERE
 ...

How can I run an EXE program from a Windows Service using C#?

i have tried this article Code Project, it is working fine for me. I have used the code too. article is excellent in explanation with screenshot.

I am adding necessary explanation to this scenario

You have just booted up your computer and are about to log on. When you log on, the system assigns you a unique Session ID. In Windows Vista, the first User to log on to the computer is assigned a Session ID of 1 by the OS. The next User to log on will be assigned a Session ID of 2. And so on and so forth. You can view the Session ID assigned to each logged on User from the Users tab in Task Manager. enter image description here

But your windows service is brought under session ID of 0. This session is isolated from other sessions. This ultimately prevent the windows service to invoke the application running under user session's like 1 or 2.

In order to invoke the application from windows service you need to copy the control from winlogon.exe which acts as present logged user as shown in below screenshot. enter image description here

Important codes

// obtain the process id of the winlogon process that 
// is running within the currently active session
Process[] processes = Process.GetProcessesByName("winlogon");
foreach (Process p in processes)
{
    if ((uint)p.SessionId == dwSessionId)
    {
        winlogonPid = (uint)p.Id;
    }
}

// obtain a handle to the winlogon process
hProcess = OpenProcess(MAXIMUM_ALLOWED, false, winlogonPid);

// obtain a handle to the access token of the winlogon process
if (!OpenProcessToken(hProcess, TOKEN_DUPLICATE, ref hPToken))
{
    CloseHandle(hProcess);
    return false;
}

// Security attibute structure used in DuplicateTokenEx and   CreateProcessAsUser
// I would prefer to not have to use a security attribute variable and to just 
// simply pass null and inherit (by default) the security attributes
// of the existing token. However, in C# structures are value types and   therefore
// cannot be assigned the null value.
SECURITY_ATTRIBUTES sa = new SECURITY_ATTRIBUTES();
sa.Length = Marshal.SizeOf(sa);

// copy the access token of the winlogon process; 
// the newly created token will be a primary token
if (!DuplicateTokenEx(hPToken, MAXIMUM_ALLOWED, ref sa, 
    (int)SECURITY_IMPERSONATION_LEVEL.SecurityIdentification, 
    (int)TOKEN_TYPE.TokenPrimary, ref hUserTokenDup))
    {
      CloseHandle(hProcess);
      CloseHandle(hPToken);
      return false;
    }

 STARTUPINFO si = new STARTUPINFO();
 si.cb = (int)Marshal.SizeOf(si);

// interactive window station parameter; basically this indicates 
// that the process created can display a GUI on the desktop
si.lpDesktop = @"winsta0\default";

// flags that specify the priority and creation method of the process
int dwCreationFlags = NORMAL_PRIORITY_CLASS | CREATE_NEW_CONSOLE;

// create a new process in the current User's logon session
 bool result = CreateProcessAsUser(hUserTokenDup,  // client's access token
                            null,             // file to execute
                            applicationName,  // command line
                            ref sa,           // pointer to process    SECURITY_ATTRIBUTES
                            ref sa,           // pointer to thread SECURITY_ATTRIBUTES
                            false,            // handles are not inheritable
                            dwCreationFlags,  // creation flags
                            IntPtr.Zero,      // pointer to new environment block 
                            null,             // name of current directory 
                            ref si,           // pointer to STARTUPINFO structure
                            out procInfo      // receives information about new process
                            );

&& (AND) and || (OR) in IF statements

No it won't, Java will short-circuit and stop evaluating once it knows the result.

What's the difference between a word and byte?

If a machine is byte-addressable and a word is the smallest unit that can be addressed on memory then I guess a word would be a byte!

How to get 30 days prior to current date?

I use date.js. It handles this easily and takes care of all the leap-year nastiness.

Replacing values from a column using a condition in R

I arrived here from a google search, since my other code is 'tidy' so leaving the 'tidy' way for anyone who else who may find it useful

library(dplyr)
iris %>% 
  mutate(Species = ifelse(as.character(Species) == "virginica", "newValue", as.character(Species)))

How to display the string html contents into webbrowser control?

Old question, but here's my go-to for this operation.

If browser.Document IsNot Nothing Then
    browser.Document.OpenNew(True)
    browser.Document.Write(My.Resources.htmlTemplate)
Else
    browser.DocumentText = My.Resources.htmlTemplate
End If

And be sure that any browser.Navigating event DOES NOT cancel "about:blank" URLs. Example event below for full control of WebBrowser navigating.

Private Sub browser_Navigating(sender As Object, e As WebBrowserNavigatingEventArgs) Handles browser.Navigating

    Try
        Me.Cursor = Cursors.WaitCursor

        Select Case e.Url.Scheme

            Case Constants.App_Url_Scheme

                Dim query As Specialized.NameValueCollection = System.Web.HttpUtility.ParseQueryString(e.Url.Query)

                Select Case e.Url.Host

                    Case Constants.Navigation.URLs.ToggleExpander.Host

                        Dim nodeID As String = query.Item(Constants.Navigation.URLs.ToggleExpander.Parameters.NodeID)

                        :
                        :
                        <other operations here>
                        :
                        :

                End Select

            Case Else
                e.Cancel = (e.Url.ToString() <> "about:blank")

        End Select

    Catch ex As Exception
        ExceptionBox.Show(ex, "Operation failed.")
    Finally
        Me.Cursor = Cursors.Default
    End Try

End Sub

CURRENT_TIMESTAMP in milliseconds

To get the Unix timestamp in seconds in MySQL:

select UNIX_TIMESTAMP();

Details: http://dev.mysql.com/doc/refman/5.5/en/date-and-time-functions.html#function_unix-timestamp

Not tested PostgreSQL, but according to this site it should work: http://www.raditha.com/postgres/timestamp.php

select round( date_part( 'epoch', now() ) );

How to join three table by laravel eloquent model

With Eloquent its very easy to retrieve relational data. Checkout the following example with your scenario in Laravel 5.

We have three models:

1) Article (belongs to user and category)

2) Category (has many articles)

3) User (has many articles)


1) Article.php

<?php

namespace App\Models;
 use Eloquent;

class Article extends Eloquent{

    protected $table = 'articles';

    public function user()
    {
        return $this->belongsTo('App\Models\User');
    }

    public function category()
    {
        return $this->belongsTo('App\Models\Category');
    }

}

2) Category.php

<?php

namespace App\Models;

use Eloquent;

class Category extends Eloquent
{
    protected $table = "categories";

    public function articles()
    {
        return $this->hasMany('App\Models\Article');
    }

}

3) User.php

<?php

namespace App\Models;
use Eloquent;

class User extends Eloquent
{
    protected $table = 'users';

    public function articles()
    {
        return $this->hasMany('App\Models\Article');
    }

}

You need to understand your database relation and setup in models. User has many articles. Category has many articles. Articles belong to user and category. Once you setup the relationships in Laravel, it becomes easy to retrieve the related information.

For example, if you want to retrieve an article by using the user and category, you would need to write:

$article = \App\Models\Article::with(['user','category'])->first();

and you can use this like so:

//retrieve user name 
$article->user->user_name  

//retrieve category name 
$article->category->category_name

In another case, you might need to retrieve all the articles within a category, or retrieve all of a specific user`s articles. You can write it like this:

$categories = \App\Models\Category::with('articles')->get();

$users = \App\Models\Category::with('users')->get();

You can learn more at http://laravel.com/docs/5.0/eloquent

RSA encryption and decryption in Python

In order to make it work you need to convert key from str to tuple before decryption(ast.literal_eval function). Here is fixed code:

import Crypto
from Crypto.PublicKey import RSA
from Crypto import Random
import ast

random_generator = Random.new().read
key = RSA.generate(1024, random_generator) #generate pub and priv key

publickey = key.publickey() # pub key export for exchange

encrypted = publickey.encrypt('encrypt this message', 32)
#message to encrypt is in the above line 'encrypt this message'

print 'encrypted message:', encrypted #ciphertext
f = open ('encryption.txt', 'w')
f.write(str(encrypted)) #write ciphertext to file
f.close()

#decrypted code below

f = open('encryption.txt', 'r')
message = f.read()


decrypted = key.decrypt(ast.literal_eval(str(encrypted)))

print 'decrypted', decrypted

f = open ('encryption.txt', 'w')
f.write(str(message))
f.write(str(decrypted))
f.close()

SQL ON DELETE CASCADE, Which Way Does the Deletion Occur?

Cascade will work when you delete something on table Courses. Any record on table BookCourses that has reference to table Courses will be deleted automatically.

But when you try to delete on table BookCourses only the table itself is affected and not on the Courses

follow-up question: why do you have CourseID on table Category?

Maybe you should restructure your schema into this,

CREATE TABLE Categories 
(
  Code CHAR(4) NOT NULL PRIMARY KEY,
  CategoryName VARCHAR(63) NOT NULL UNIQUE
);

CREATE TABLE Courses 
(
  CourseID INT NOT NULL PRIMARY KEY,
  BookID INT NOT NULL,
  CatCode CHAR(4) NOT NULL,
  CourseNum CHAR(3) NOT NULL,
  CourseSec CHAR(1) NOT NULL,
);

ALTER TABLE Courses
ADD FOREIGN KEY (CatCode)
REFERENCES Categories(Code)
ON DELETE CASCADE;

File Upload In Angular?

Since the code sample is a bit outdated I thought I'd share a more recent approach, using Angular 4.3 and the new(er) HttpClient API, @angular/common/http

export class FileUpload {

@ViewChild('selectedFile') selectedFileEl;

uploadFile() {
let params = new HttpParams();

let formData = new FormData();
formData.append('upload', this.selectedFileEl.nativeElement.files[0])

const options = {
    headers: new HttpHeaders().set('Authorization', this.loopBackAuth.accessTokenId),
    params: params,
    reportProgress: true,
    withCredentials: true,
}

this.http.post('http://localhost:3000/api/FileUploads/fileupload', formData, options)
.subscribe(
    data => {
        console.log("Subscribe data", data);
    },
    (err: HttpErrorResponse) => {
        console.log(err.message, JSON.parse(err.error).error.message);
    }
)
.add(() => this.uploadBtn.nativeElement.disabled = false);//teardown
}

What is the difference between null and undefined in JavaScript?

When you declare a variable in javascript, it is assigned the value undefined. This means the variable is untouched and can be assigned any value in future. It also implies that you don't know the value that this variable is going to hold at the time of declaration.

Now you can explicitly assign a variable null. It means that the variable does not have any value. For example - Some people don't have a middle name. So in such a case its better to assign the value null to the middlename variable of a person object.

Now suppose that someone is accessing the middlename variable of your person object and it has the value undefined. He wouldn't know if the developer forgot to initialize this variable or if it didn't have any value. If it has the value null, then the user can easily infer that middlename doesn't have any value and it is not an untouched variable.

How to implement swipe gestures for mobile devices?

The simplest solution I've found that doesn't require a plugin:

document.addEventListener('touchstart', handleTouchStart, false);        
document.addEventListener('touchmove', handleTouchMove, false);
var xDown = null;                                                        
var yDown = null;  

function handleTouchStart(evt) {                                         
    xDown = evt.touches[0].clientX;                                      
    yDown = evt.touches[0].clientY;                                      
}; 

function handleTouchMove(evt) {
    if ( ! xDown || ! yDown ) {
        return;
    }
    var xUp = evt.touches[0].clientX;                                    
    var yUp = evt.touches[0].clientY;
    var xDiff = xDown - xUp;
    var yDiff = yDown - yUp;

    if ( Math.abs( xDiff ) > Math.abs( yDiff ) ) {/*most significant*/
        if ( xDiff > 0 ) {
        /* left swipe */ 
        } else {
        /* right swipe */
        }                       
    } else {
        if ( yDiff > 0 ) {
        /* up swipe */ 
        } else { 
        /* down swipe */
        }                                                                 
    }
    /* reset values */
    xDown = null;
    yDown = null;                                             
};