Programs & Examples On #Perception

In SO, Perception means what an user believes by observing something.

Converting RGB to grayscale/intensity

is all this really necessary, human perception and CRT vs LCD will vary, but the R G B intensity does not, Why not L = (R + G + B)/3 and set the new RGB to L, L, L?

How do you performance test JavaScript code?

Quick answer

On jQuery (more specifically on Sizzle), we use this (checkout master and open speed/index.html on your browser), which in turn uses benchmark.js. This is used to performance test the library.

Long answer

If the reader doesn't know the difference between benchmark, workload and profilers, first read some performance testing foundations on the "readme 1st" section of spec.org. This is for system testing, but understanding this foundations will help JS perf testing as well. Some highlights:

What is a benchmark?

A benchmark is "a standard of measurement or evaluation" (Webster’s II Dictionary). A computer benchmark is typically a computer program that performs a strictly defined set of operations - a workload - and returns some form of result - a metric - describing how the tested computer performed. Computer benchmark metrics usually measure speed: how fast was the workload completed; or throughput: how many workload units per unit time were completed. Running the same computer benchmark on multiple computers allows a comparison to be made.

Should I benchmark my own application?

Ideally, the best comparison test for systems would be your own application with your own workload. Unfortunately, it is often impractical to get a wide base of reliable, repeatable and comparable measurements for different systems using your own application with your own workload. Problems might include generation of a good test case, confidentiality concerns, difficulty ensuring comparable conditions, time, money, or other constraints.

If not my own application, then what?

You may wish to consider using standardized benchmarks as a reference point. Ideally, a standardized benchmark will be portable, and may already have been run on the platforms that you are interested in. However, before you consider the results you need to be sure that you understand the correlation between your application/computing needs and what the benchmark is measuring. Are the benchmarks similar to the kinds of applications you run? Do the workloads have similar characteristics? Based on your answers to these questions, you can begin to see how the benchmark may approximate your reality.

Note: A standardized benchmark can serve as reference point. Nevertheless, when you are doing vendor or product selection, SPEC does not claim that any standardized benchmark can replace benchmarking your own actual application.

Performance testing JS

Ideally, the best perf test would be using your own application with your own workload switching what you need to test: different libraries, machines, etc.

If this is not feasible (and usually it is not). The first important step: define your workload. It should reflect your application's workload. In this talk, Vyacheslav Egorov talks about shitty workloads you should avoid.

Then, you could use tools like benchmark.js to assist you collect metrics, usually speed or throughput. On Sizzle, we're interested in comparing how fixes or changes affect the systemic performance of the library.

If something is performing really bad, your next step is to look for bottlenecks.

How do I find bottlenecks? Profilers

What is the best way to profile javascript execution?

Can't Find Theme.AppCompat.Light for New Android ActionBar Support

In my case the problem occurred since I wanted to use a SDK that doesnt include the required library. When I increased the min. SDK level the problem dissappeared. Of course directly including the library's itself, should remove the error as well.

Cast int to varchar

Yes

SELECT id || '' FROM some_table;
or SELECT id::text FROM some_table;

is postgresql, but mySql doesn't allow that!

short cut in mySql:

SELECT concat(id, '') FROM some_table;

Android YouTube app Play Video Intent

EDIT: The below implementation proved to have problems on at least some HTC devices (they crashed). For that reason I don't use setclassname and stick with the action chooser menu. I strongly discourage using my old implementation.

Following is the old implementation:

Intent intent = new Intent(android.content.Intent.ACTION_VIEW, Uri.parse(youtubelink));
if(Utility.isAppInstalled("com.google.android.youtube", getActivity())) {
    intent.setClassName("com.google.android.youtube", "com.google.android.youtube.WatchActivity");
}
startActivity(intent);

Where Utility is my own personal utility class with following methode:

public static boolean isAppInstalled(String uri, Context context) {
    PackageManager pm = context.getPackageManager();
    boolean installed = false;
    try {
        pm.getPackageInfo(uri, PackageManager.GET_ACTIVITIES);
        installed = true;
    } catch (PackageManager.NameNotFoundException e) {
        installed = false;
    }
    return installed;
}

First I check if youtube is installed, if it is installed, I tell android which package I prefer to open my intent.

Vertical Align text in a Label

To do this you should alter the vertical-align property of the input.

<dd><label class="<?=$email_confirm_class;?>" style="text-align:right; padding-right:3px">Confirm Email</label><input class="text" type="text" style="vertical-align: middle; border:none;" name="email_confirm" id="email_confirm" size="18" value="<?=$_POST['email_confirm'];?>" tabindex="4" /> *</dd>

Here is a more complete version. It has been tested in IE 8 and it works. see the difference by removing the vertical-align: middle from the input:

<html><head></head><body><dl><dt>test</dt><dd><label class="test" style="text-align:right; padding-right:3px">Confirm Email</label><input class="text" type="text" style="vertical-align: middle; font-size: 22px" name="email_confirm" id="email_confirm" size="28" value="test" tabindex="4" /> *</dd></dl></body></html>

Parsing Query String in node.js

require('url').parse('/status?name=ryan', {parseQueryString: true}).query

returns

{ name: 'ryan' }

ref: https://nodejs.org/api/url.html#url_urlobject_query

How to upload files to server using Putty (ssh)

You need an scp client. Putty is not one. You can use WinSCP or PSCP. Both are free software.

How to get all child inputs of a div element (jQuery)

You need

var i = $("#panel input"); 

or, depending on what exactly you want (see below)

var i = $("#panel :input"); 

the > will restrict to children, you want all descendants.

EDIT: As Nick pointed out, there's a subtle difference between $("#panel input") and $("#panel :input).

The first one will only retrieve elements of type input, that is <input type="...">, but not <textarea>, <button> and <select> elements. Thanks Nick, didn't know this myself and corrected my post accordingly. Left both options, because I guess the OP wasn't aware of that either and -technically- asked for inputs... :-)

Multiple Indexes vs Multi-Column Indexes

One item that seems to have been missed is star transformations. Index Intersection operators resolve the predicate by calculating the set of rows hit by each of the predicates before any I/O is done on the fact table. On a star schema you would index each individual dimension key and the query optimiser can resolve which rows to select by the index intersection computation. The indexes on individual columns give the best flexibility for this.

pandas: filter rows of DataFrame with operator chaining

This is unappealing as it requires I assign df to a variable before being able to filter on its values.

df[df["column_name"] != 5].groupby("other_column_name")

seems to work: you can nest the [] operator as well. Maybe they added it since you asked the question.

How to add column to numpy array

The easiest solution is to use numpy.insert().

The Advantage of np.insert() over np.append is that you can insert the new columns into custom indices.

import numpy as np

X = np.arange(20).reshape(10,2)

X = np.insert(X, [0,2], np.random.rand(X.shape[0]*2).reshape(-1,2)*10, axis=1)
'''

Adjust table column width to content size

If you want the table to still be 100% then set one of the columns to have a width:100%; That will extend that column to fill the extra space and allow the other columns to keep their auto width :)

Are arrays passed by value or passed by reference in Java?

Kind of a trick realty... Even references are passed by value in Java, hence a change to the reference itself being scoped at the called function level. The compiler and/or JVM will often turn a value type into a reference.

When to use .First and when to use .FirstOrDefault with LINQ?

This type of the function belongs to element operators. Some useful element operators are defined below.

  1. First/FirstOrDefault
  2. Last/LastOrDefault
  3. Single/SingleOrDefault

We use element operators when we need to select a single element from a sequence based on a certain condition. Here is an example.

  List<int> items = new List<int>() { 8, 5, 2, 4, 2, 6, 9, 2, 10 };

First() operator returns the first element of a sequence after satisfied the condition. If no element is found then it will throw an exception.

int result = items.Where(item => item == 2).First();

FirstOrDefault() operator returns the first element of a sequence after satisfied the condition. If no element is found then it will return default value of that type.

int result1 = items.Where(item => item == 2).FirstOrDefault();

How do you strip a character out of a column in SQL Server?

Use the "REPLACE" string function on the column in question:

UPDATE (yourTable)
SET YourColumn = REPLACE(YourColumn, '*', '')
WHERE (your conditions)

Replace the "*" with the character you want to strip out and specify your WHERE clause to match the rows you want to apply the update to.

Of course, the REPLACE function can also be used - as other answerer have shown - in a SELECT statement - from your question, I assumed you were trying to update a table.

Marc

How to do the Recursive SELECT query in MySQL?

Stored procedure is the best way to do it. Because Meherzad's solution would work only if the data follows the same order.

If we have a table structure like this

col1 | col2 | col3
-----+------+------
 3   | k    | 7
 5   | d    | 3
 1   | a    | 5
 6   | o    | 2
 2   | 0    | 8

It wont work. SQL Fiddle Demo

Here is a sample procedure code to achieve the same.

delimiter //
CREATE PROCEDURE chainReaction 
(
    in inputNo int
) 
BEGIN 
    declare final_id int default NULL;
    SELECT col3 
    INTO final_id 
    FROM table1
    WHERE col1 = inputNo;
    IF( final_id is not null) THEN
        INSERT INTO results(SELECT col1, col2, col3 FROM table1 WHERE col1 = inputNo);
        CALL chainReaction(final_id);   
    end if;
END//
delimiter ;

call chainReaction(1);
SELECT * FROM results;
DROP TABLE if exists results;

How do I load an HTML page in a <div> using JavaScript?

When using

$("#content").load("content.html");

Then remember that you can not "debug" in chrome locally, because XMLHttpRequest cannot load -- This does NOT mean that it does not work, it just means that you need to test your code on same domain aka. your server

Changing image sizes proportionally using CSS?

this is a known problem with CSS resizing, unless all images have the same proportion, you have no way to do this via CSS.

The best approach would be to have a container, and resize one of the dimensions (always the same) of the images. In my example I resized the width.

If the container has a specified dimension (in my example the width), when telling the image to have the width at 100%, it will make it the full width of the container. The auto at the height will make the image have the height proportional to the new width.

Ex:

HTML:

<div class="container">
<img src="something.png" />
</div>

<div class="container">
<img src="something2.png" />
</div>

CSS:

.container {
    width: 200px;
    height: 120px;
}

/* resize images */
.container img {
    width: 100%;
    height: auto;
}

Display the current time and date in an Android application

From How to get full date with correct format?:

Please, use

android.text.format.DateFormat.getDateFormat(Context context)
android.text.format.DateFormat.getTimeFormat(Context context)

to get valid time and date formats in sense of current user settings (12/24 time format, for example).

import android.text.format.DateFormat;

private void some() {
    final Calendar t = Calendar.getInstance();
    textView.setText(DateFormat.getTimeFormat(this/*Context*/).format(t.getTime()));
}

How to update data in one table from corresponding data in another table in SQL Server 2005

 UPDATE Employee SET Empid=emp3.empid 
 FROM EMP_Employee AS emp3
 WHERE Employee.Empid=emp3.empid

What is the difference between resource and endpoint?

The terms resource and endpoint are often used synonymously. But in fact they do not mean the same thing.

The term endpoint is focused on the URL that is used to make a request.
The term resource is focused on the data set that is returned by a request.

Now, the same resource can often be accessed by multiple different endpoints.
Also the same endpoint can return different resources, depending on a query string.

Let us see some examples:

Different endpoints accessing the same resource

Have a look at the following examples of different endpoints:

/api/companies/5/employees/3
/api/v2/companies/5/employees/3
/api/employees/3

They obviously could all access the very same resource in a given API.

Also an existing API could be changed completely. This could lead to new endpoints that would access the same old resources using totally new and different URLs:

/api/employees/3
/new_api/staff/3

One endpoint accessing different resources

If your endpoint returns a collection, you could implement searching/filtering/sorting using query strings. As a result the following URLs all use the same endpoint (/api/companies), but they can return different resources (or resource collections, which by definition are resources in themselves):

/api/companies
/api/companies?sort=name_asc
/api/companies?location=germany
/api/companies?search=siemens

Facebook Like-Button - hide count?

Accepted answer is good, but be careful with multilingual pages. The text differ in length:

English: Like

Dutch: Vind ik leuk

German: Gefällt mir

Just a heads up.

Scikit-learn train_test_split with indices

If you are using pandas you can access the index by calling .index of whatever array you wish to mimic. The train_test_split carries over the pandas indices to the new dataframes.

In your code you simply use x1.index and the returned array is the indexes relating to the original positions in x.

C# How do I click a button by hitting Enter whilst textbox has focus?

Or you can just use this simple 2 liner code :)

if (e.KeyCode == Keys.Enter)
            button1.PerformClick();

Stopping Docker containers by image name - Ubuntu

Adding on top of @VonC superb answer, here is a ZSH function that you can add into your .zshrc file:

dockstop() {
  docker rm $(docker stop $(docker ps -a -q --filter ancestor="$1" --format="{{.ID}}"))
}

Then in your command line, simply do dockstop myImageName and it will stop and remove all containers that were started from an image called myImageName.

How to define hash tables in Bash?

This is what I was looking for here:

declare -A hashmap
hashmap["key"]="value"
hashmap["key2"]="value2"
echo "${hashmap["key"]}"
for key in ${!hashmap[@]}; do echo $key; done
for value in ${hashmap[@]}; do echo $value; done
echo hashmap has ${#hashmap[@]} elements

This did not work for me with bash 4.1.5:

animals=( ["moo"]="cow" )

Wireshark vs Firebug vs Fiddler - pros and cons?

I use both Charles Proxy and Fiddler for my HTTP/HTTPS level debugging.

Pros of Charles Proxy:

  1. Handles HTTPS better (you get a Charles Certificate which you'd put in 'Trusted Authorities' list)
  2. Has more features like Load/Save Session (esp. useful when debugging multiple pages), Mirror a website (useful in caching assets and hence faster debugging), etc.
  3. As mentioned by jburgess, handles AMF.
  4. Displays JSON, XML and other kind of responses in a tree structure, making it easier to read. Displays images in image responses instead of binary data.

Cons of Charles Proxy:

  1. Cost :-)

How to ftp with a batch file?

This is an old post however, one alternative is to use the command options:

ftp -n -s:ftpcmd.txt

the -n will suppress the initial login and then the file contents would be: (replace the 127.0.0.1 with your FTP site url)

open 127.0.0.1
user myFTPuser myftppassword
other commands here...

This avoids the user/password on separate lines

jQuery - how can I find the element with a certain id?

This is one more option to find the element for above question

$("#tbIntervalos").find('td[id="'+horaInicial+'"]')

Change :hover CSS properties with JavaScript

If you use lightweight html ux lang, check here an example, write:

div root
 .onmouseover = ev => {root.style.backgroundColor='red'}
 .onmouseleave = ev => {root.style.backgroundColor='initial'}

The code above performes the css :hover metatag.

Format cell color based on value in another sheet and cell

Here's how I did it in Excel 2003 using conditional formatting.

To apply conditional formatting to Sheet1 using values from Sheet2, you need to mirror the values into Sheet1.

Creating a mirror of Sheet2, column B in Sheet 1

  1. Go to Sheet1.
  2. Insert a new column by right-clicking column A's header and selecting "Insert".
  3. Enter the following formula into A1:

    =IF(ISBLANK(Sheet2!B1),"",Sheet2!B1)

  4. Copy A1 by right-clicking it and selecting "Copy".
  5. Paste the formula into column A by right-clicking its header and selecting "Paste".

Sheet1, column A should now exactly mirror the values in Sheet2, column B.

(Note: if you don't like it in column A, it works just as well to have it in column Z or anywhere else.)

Applying the conditional formatting

  1. Stay on Sheet1.
  2. Select column B by left-clicking its header.
  3. Select the menu item Format > Conditional Formatting...
  4. Change Condition 1 to "Formula is" and enter this formula:

    =MATCH(B1,$A:$A,0)

  5. Click the Format... button and select a green background.

You should now see the green background applied to the matching cells in Sheet1.

Hiding the mirror column

  1. Stay on Sheet1.
  2. Right-click the header on column A and select "Hide".

This should automatically update Sheet1 whenever anything in Sheet2 is changed.

Make one div visible and another invisible

Making it invisible with visibility still makes it use up space. Rather try set the display to none to make it invisible, and then set the display to block to make it visible.

How to prevent favicon.ico requests?

A very simple solution is put the below code in your .htaccess. I had the same issue and it solve my problem.

<IfModule mod_alias.c>
    RedirectMatch 403 favicon.ico
</IfModule>

Reference: http://perishablepress.com/block-favicon-url-404-requests/

Make the first character Uppercase in CSS

Make it lowercase first:

.m_title {text-transform: lowercase}

Then make it the first letter uppercase:

.m_title:first-letter {text-transform: uppercase}

"text-transform: capitalize" works for a word; but if you want to use for sentences this solution is perfect.

Android OnClickListener - identify a button

use setTag();

like this:

@Override    
public void onClick(View v) {     
    int tag = (Integer) v.getTag();     
    switch (tag) {     
    case 1:     
        System.out.println("button1 click");     
        break;     
    case 2:     
        System.out.println("button2 click");     
       break;   
    }     
}     

Android Use Done button on Keyboard to click button

if you want to catch the keyboard enter button for doing your job which you want to done through any event like button click, you can write the below simple code for that text view

Edittext ed= (EditText) findViewById(R.id.edit_text);

ed.setOnEditorActionListener(new TextView.OnEditorActionListener() {
@Override
public boolean onEditorAction(TextView v, int actionId, KeyEvent event) {
    if (actionId == EditorInfo.IME_ACTION_DONE) {
        // Do you job here which you want to done through event
    }
    return false;
}
});

Change the selected value of a drop-down list with jQuery

<asp:DropDownList id="MyDropDown" runat="server" />

Use $("select[name$='MyDropDown']").val().

ORDER BY using Criteria API

You need to create an alias for the mother.kind. You do this like so.

Criteria c = session.createCriteria(Cat.class);
c.createAlias("mother.kind", "motherKind");
c.addOrder(Order.asc("motherKind.value"));
return c.list();

Warning: mysqli_query() expects parameter 1 to be mysqli, resource given

You are mixing mysqli and mysql extensions, which will not work.

You need to use

$myConnection= mysqli_connect("$db_host","$db_username","$db_pass") or die ("could not connect to mysql"); 

mysqli_select_db($myConnection, "mrmagicadam") or die ("no database");   

mysqli has many improvements over the original mysql extension, so it is recommended that you use mysqli.

Getting the error "Java.lang.IllegalStateException Activity has been destroyed" when using tabs with ViewPager

Wanted to add that my problem was in an activity where I tried to make a FragmentTransaction in onCreate BEFORE I called super.onCreate(). I just moved super.onCreate() to top of function and was worked fine.

How to get the background color code of an element in hex?

You have the color you just need to convert it into the format you want.

Here's a script that should do the trick: http://www.phpied.com/rgb-color-parser-in-javascript/

Window vs Page vs UserControl for WPF navigation?

All depends on the app you're trying to build. Use Windows if you're building a dialog based app. Use Pages if you're building a navigation based app. UserControls will be useful regardless of the direction you go as you can use them in both Windows and Pages.

A good place to start exploring is here: http://windowsclient.net/learn

Converting a float to a string without rounding it

len(repr(float(x)/3))

However I must say that this isn't as reliable as you think.

Floats are entered/displayed as decimal numbers, but your computer (in fact, your standard C library) stores them as binary. You get some side effects from this transition:

>>> print len(repr(0.1))
19
>>> print repr(0.1)
0.10000000000000001

The explanation on why this happens is in this chapter of the python tutorial.

A solution would be to use a type that specifically tracks decimal numbers, like python's decimal.Decimal:

>>> print len(str(decimal.Decimal('0.1')))
3

How to convert String into Hashmap in java

This is one solution. If you want to make it more generic, you can use the StringUtils library.

String value = "{first_name = naresh,last_name = kumar,gender = male}";
value = value.substring(1, value.length()-1);           //remove curly brackets
String[] keyValuePairs = value.split(",");              //split the string to creat key-value pairs
Map<String,String> map = new HashMap<>();               

for(String pair : keyValuePairs)                        //iterate over the pairs
{
    String[] entry = pair.split("=");                   //split the pairs to get key and value 
    map.put(entry[0].trim(), entry[1].trim());          //add them to the hashmap and trim whitespaces
}

For example you can switch

 value = value.substring(1, value.length()-1);

to

 value = StringUtils.substringBetween(value, "{", "}");

if you are using StringUtils which is contained in apache.commons.lang package.

Confirm button before running deleting routine from website

You have 2 options

1) Use javascript to confirm deletion (use onsubmit event handler), however if the client has JS disabled, you're in trouble.

2) Use PHP to echo out a confirmation message, along with the contents of the form (hidden if you like) as well as a submit button called "confirmation", in PHP check if $_POST["confirmation"] is set.

Fatal error: Call to undefined function pg_connect()

Uncommenting extension=php_pgsql.dll in the php.ini configuration files does work but, you may have to also restart your XAMPP server to finally get it working. I had to do this.

How to convert a currency string to a double with jQuery or Javascript?

This is my function. Works with all currencies..

function toFloat(num) {
    dotPos = num.indexOf('.');
    commaPos = num.indexOf(',');

    if (dotPos < 0)
        dotPos = 0;

    if (commaPos < 0)
        commaPos = 0;

    if ((dotPos > commaPos) && dotPos)
        sep = dotPos;
    else {
        if ((commaPos > dotPos) && commaPos)
            sep = commaPos;
        else
            sep = false;
    }

    if (sep == false)
        return parseFloat(num.replace(/[^\d]/g, ""));

    return parseFloat(
        num.substr(0, sep).replace(/[^\d]/g, "") + '.' + 
        num.substr(sep+1, num.length).replace(/[^0-9]/, "")
    );

}

Usage : toFloat("$1,100.00") or toFloat("1,100.00$")

How to join entries in a set into one string?

', '.join(set_3)

The join is a string method, not a set method.

Angular2 Routing with Hashtag to page anchor

Although Günter's answer is correct, it doesn't cover the "jump to" the anchor tag part.

Therefore, additionally to:

<a [routerLink]="['somepath']" fragment="Test">Jump to 'Test' anchor </a>
this._router.navigate( ['/somepath', id ], {fragment: 'test'});

... in the component (parent) where you need a "jump to" behavior, add:

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

class MyAppComponent {
  constructor(router: Router) {

    router.events.subscribe(s => {
      if (s instanceof NavigationEnd) {
        const tree = router.parseUrl(router.url);
        if (tree.fragment) {
          const element = document.querySelector("#" + tree.fragment);
          if (element) { element.scrollIntoView(true); }
        }
      }
    });

  }
}

Please note that this is a workaround! Follow this github issue for future updates. Credits to Victor Savkin for providing the solution!

Java String new line

Platform-Independent Line Breaks

finalString = "physical" + System.lineSeparator() + "distancing";
System.out.println(finalString);

Output:

physical
distancing

Notes:
Java 6: System.getProperty("line.separator")
Java 7 & above: System.lineSeparator()

Is there any advantage of using map over unordered_map in case of trivial keys?

From: http://www.cplusplus.com/reference/map/map/

"Internally, the elements in a map are always sorted by its key following a specific strict weak ordering criterion indicated by its internal comparison object (of type Compare).

map containers are generally slower than unordered_map containers to access individual elements by their key, but they allow the direct iteration on subsets based on their order."

PNG transparency issue in IE8

I had the same thing happen to a PNG with transparency that was set as the background-image of an <A> element with opacity applied.

The fix was to set the background-color of the <A> element.

So, the following:

filter: alpha(opacity=40);
-moz-opacity: 0.4;
-khtml-opacity: 0.4;
opacity: 0.4;
background-image: ...;

Turns into:

/* "Overwritten" by the background-image. However this fixes the IE7 and IE8 PNG-transparency-plus-opacity bug. */
background-color: #FFFFFF; 

filter: alpha(opacity=40);
-moz-opacity: 0.4;
-khtml-opacity: 0.4;
opacity: 0.4;
background-image: ...;

Python: "Indentation Error: unindent does not match any outer indentation level"

Maybe it's this part:

if speed      > self.buginfo["maxspeed"]: self.buginfo["maxspeed"] = speed
if generation > self.buginfo["maxgen"]  : self.buginfo["maxgen"]   = generation

Try to remove the extra space to make it look aligned.

Edit: from pep8

  Yes:

      x = 1
      y = 2
      long_variable = 3

  No:

      x             = 1
      y             = 2
      long_variable = 3

Try to follow that coding style.

Angular2 equivalent of $document.ready()

You can fire an event yourself in ngOnInit() of your Angular root component and then listen for this event outside of Angular.

This is Dart code (I don't know TypeScript) but should't be to hard to translate

@Component(selector: 'app-element')
@View(
    templateUrl: 'app_element.html',
)
class AppElement implements OnInit {
  ElementRef elementRef;
  AppElement(this.elementRef);

  void ngOnInit() {
    DOM.dispatchEvent(elementRef.nativeElement, new CustomEvent('angular-ready'));
  }
}

LIKE vs CONTAINS on SQL Server

The second (assuming you means CONTAINS, and actually put it in a valid query) should be faster, because it can use some form of index (in this case, a full text index). Of course, this form of query is only available if the column is in a full text index. If it isn't, then only the first form is available.

The first query, using LIKE, will be unable to use an index, since it starts with a wildcard, so will always require a full table scan.


The CONTAINS query should be:

SELECT * FROM table WHERE CONTAINS(Column, 'test');

For loop for HTMLCollection elements

I had a problem using forEach in IE 11 and also Firefox 49

I have found a workaround like this

Array.prototype.slice.call(document.getElementsByClassName("events")).forEach(function (key) {
        console.log(key.id);
    }

How to make a owl carousel with arrows instead of next previous

If you using latest Owl Carousel 2 version. You can replace the Navigation text by fontawesome icon. Code is below.

$('.your-class').owlCarousel({
        loop: true,
        items: 1, // Select Item Number
        autoplay:true,
        dots: false,
        nav: true,
        navText: ["<i class='fa fa-long-arrow-left'></i>","<i class='fa fa-long-arrow-right'></i>"],

    });

Missing maven .m2 folder

Is there some command to create this folder?

If smb face this issue again, you should know the most simple way to create .m2 folder.
If you unzipped maven and set up maven path variable - just try mvn clean command from anywhere you like!
Dont be afraid of error messages when running - it works and creates needed directory.

Cannot simply use PostgreSQL table name ("relation does not exist")

I had problems with this and this is the story (sad but true) :

  1. If your table name is all lower case like : accounts you can use: select * from AcCounTs and it will work fine

  2. If your table name is all lower case like : accounts The following will fail: select * from "AcCounTs"

  3. If your table name is mixed case like : Accounts The following will fail: select * from accounts

  4. If your table name is mixed case like : Accounts The following will work OK: select * from "Accounts"

I dont like remembering useless stuff like this but you have to ;)

Python: Binary To Decimal Conversion

You can use int casting which allows the base specification.

int(b, 2)  # Convert a binary string to a decimal int.

Find Nth occurrence of a character in a string

Here's another LINQ solution:

string input = "dtststx";
char searchChar = 't';
int occurrencePosition = 3; // third occurrence of the char
var result = input.Select((c, i) => new { Char = c, Index = i })
                  .Where(item => item.Char == searchChar)
                  .Skip(occurrencePosition - 1)
                  .FirstOrDefault();

if (result != null)
{
    Console.WriteLine("Position {0} of '{1}' occurs at index: {2}",
                        occurrencePosition, searchChar, result.Index);
}
else
{
    Console.WriteLine("Position {0} of '{1}' not found!",
                        occurrencePosition, searchChar);
}

Just for fun, here's a Regex solution. I saw some people initially used Regex to count, but when the question changed no updates were made. Here is how it can be done with Regex - again, just for fun. The traditional approach is best for simplicity.

string input = "dtststx";
char searchChar = 't';
int occurrencePosition = 3; // third occurrence of the char

Match match = Regex.Matches(input, Regex.Escape(searchChar.ToString()))
                   .Cast<Match>()
                   .Skip(occurrencePosition - 1)
                   .FirstOrDefault();

if (match != null)
    Console.WriteLine("Index: " + match.Index);
else
    Console.WriteLine("Match not found!");

Apply function to pandas groupby

Try:

g = pd.DataFrame(['A','B','A','C','D','D','E'])

# Group by the contents of column 0 
gg = g.groupby(0)  

# Create a DataFrame with the counts of each letter
histo = gg.apply(lambda x: x.count())

# Add a new column that is the count / total number of elements    
histo[1] = histo.astype(np.float)/len(g) 

print histo

Output:

   0         1
0             
A  2  0.285714
B  1  0.142857
C  1  0.142857
D  2  0.285714
E  1  0.142857

How to change the color of a SwitchCompat from AppCompat library

So some days I lack brain cells and:

<android.support.v7.widget.SwitchCompat
        android:layout_width="match_parent"
        android:layout_height="wrap_content"
        style="@style/CustomSwitchStyle"/>

does not apply the theme because style is incorrect. I was supposed to use app:theme :P

<android.support.v7.widget.SwitchCompat
        android:layout_width="match_parent"
        android:layout_height="wrap_content"
        app:theme="@style/CustomSwitchStyle"/>

Whoopsies. This post was what gave me insight into my mistake...hopefully if someone stumbles across this it will help them like it did me. Thank you Gaëtan Maisse for your answer

Unit testing with mockito for constructors

I believe, it is not possible to mock constructors using mockito. Instead, I suggest following approach

Class First {

   private Second second;

   public First(int num, String str) {
     if(second== null)
     {
       //when junit runs, you get the mocked object(not null), hence don't 
       //initialize            
       second = new Second(str);
     }
     this.num = num;
   }

   ... // some other methods
}

And, for test:

class TestFirst{
    @InjectMock
    First first;//inject mock the real testable class
    @Mock
    Second second

    testMethod(){

        //now you can play around with any method of the Second class using its 
        //mocked object(second),like:
        when(second.getSomething(String.class)).thenReturn(null);
    }
}

The target ... overrides the `OTHER_LDFLAGS` build setting defined in `Pods/Pods.xcconfig

If Xcode complains when linking, e.g. Library not found for -lPods, it doesn't detect the implicit dependencies:

Go to Product > Edit Scheme Click on Build Add the Pods static library Clean and build again

Pentaho Data Integration SQL connection

Turns out I will missing a class called mysql-connector-java-5.1.2.jar, I added it this folder (C:\Program Files\pentaho\design-tools\data-integration\lib) and it worked with a MySQL connection and my data and tables appear.

Use virtualenv with Python with Visual Studio Code in Ubuntu

I was able to use the workspace setting that other people on this page have been asking for.

In Preferences, ?+P, search for python.pythonPath in the search bar.

You should see something like:

// Path to Python, you can use a custom version of Python by modifying this setting to include the full path.
"python.pythonPath": "python"

Then click on the WORKSPACE SETTINGS tab on the right side of the window. This will make it so the setting is only applicable to the workspace you're in.

Afterwards, click on the pencil icon next to "python.pythonPath". This should copy the setting over the workspace settings.

Change the value to something like:

"python.pythonPath": "${workspaceFolder}/venv"

How to register ASP.NET 2.0 to web server(IIS7)?

The system I was working on is Windows Server 2008 Standard with IIS 7 (I guess that my experience will apply for all Windows systems of the same age).

Running

C:\Windows\Microsoft.NET\Framework\v4.0.30319\aspnet_regiis.exe -ir

SEEMED to work, as

C:\Windows\Microsoft.NET\Framework\v4.0.30319\aspnet_regiis.exe -lv

showed the .Net framework v4 registered with IIS.

But, running the same for .Net v2, namely

C:\Windows\Microsoft.NET\Framework\v2.0.50727\aspnet_regiis.exe -ir

did NOT result in

C:\Windows\Microsoft.NET\Framework\v2.0.50727\aspnet_regiis.exe -lv

showing the framework registered.

(And, for me, the installer for Kofax Capture Network Server was still missing ASP.NET.)

The solution was:

  • Open Server Manager
  • Go to Roles/Web Server (IIS)
  • Push Add Role Services
  • check ASP.NET under Application Development (and press Install)

After that, aspnet_regiis.exe -lv (either version) shows the framework registered. (And the Kofax installer was also happy and worked.)

how to insert a new line character in a string to PrintStream then use a scanner to re-read the file

The linefeed character \n is not the line separator in certain operating systems (such as windows, where it's "\r\n") - my suggestion is that you use \r\n instead, then it'll both see the line-break with only \n and \r\n, I've never had any problems using it.

Also, you should look into using a StringBuilder instead of concatenating the String in the while-loop at BookCatalog.toString(), it is a lot more effective. For instance:

public String toString() {
        BookNode current = front;
        StringBuilder sb = new StringBuilder();
        while (current!=null){
            sb.append(current.getData().toString()+"\r\n ");
            current = current.getNext();
        }
        return sb.toString();
}

How can I count text lines inside an DOM element? Can I?

Following @BobBrunius 2010 suggestion I created this with jQuery. No doubt it could be improved but it may help some.

_x000D_
_x000D_
$(document).ready(function() {_x000D_
_x000D_
  alert("Number of lines: " + getTextLinesNum($("#textbox")));_x000D_
_x000D_
});_x000D_
_x000D_
function getTextLinesNum($element) {_x000D_
_x000D_
  var originalHtml = $element.html();_x000D_
  var words = originalHtml.split(" ");_x000D_
  var linePositions = [];_x000D_
        _x000D_
  // Wrap words in spans_x000D_
  for (var i in words) {_x000D_
    words[i] = "<span>" + words[i] + "</span>";_x000D_
  }_x000D_
        _x000D_
  // Temporarily replace element content with spans. Layout should be identical._x000D_
  $element.html(words.join(" "));_x000D_
        _x000D_
  // Iterate through words and collect positions of text lines_x000D_
  $element.children("span").each(function () {_x000D_
    var lp = $(this).position().top;_x000D_
    if (linePositions.indexOf(lp) == -1) linePositions.push(lp);_x000D_
  });_x000D_
        _x000D_
  // Revert to original html content_x000D_
  $element.html(originalHtml);_x000D_
        _x000D_
  // Return number of text lines_x000D_
  return linePositions.length;_x000D_
_x000D_
}
_x000D_
#textbox {_x000D_
  width: 200px;_x000D_
  text-align: center;_x000D_
}
_x000D_
<script src="https://ajax.googleapis.com/ajax/libs/jquery/1.9.1/jquery.min.js"></script>_x000D_
<div id="textbox">Lorem ipsum dolor sit amet, consectetuer adipiscing elit,_x000D_
  <br>sed diam nonummy</div>
_x000D_
_x000D_
_x000D_

CSS to select/style first word

You have to wrap the word in a span to accomplish this.

Eclipse: How to install a plugin manually?

You can try this

click Help>Install New Software on the menu bar

enter image description here

enter image description here

enter image description here

enter image description here

Default values in a C Struct

<stdarg.h> allows you to define variadic functions (which accept an indefinite number of arguments, like printf()). I would define a function which took an arbitrary number of pairs of arguments, one which specifies the property to be updated, and one which specifies the value. Use an enum or a string to specify the name of the property.

Adding Http Headers to HttpClient

To set custom headers ON A REQUEST, build a request with the custom header before passing it to httpclient to send to http server. eg:

HttpClient client = HttpClients.custom().build();
HttpUriRequest request = RequestBuilder.get()
  .setUri(someURL)
  .setHeader(HttpHeaders.CONTENT_TYPE, "application/json")
  .build();
client.execute(request);

Default header is SET ON HTTPCLIENT to send on every request to the server.

How to change the default background color white to something else in twitter bootstrap

You can overwrite Bootstraps default CSS by adding your own rules.

<style type="text/css">
   body { background: navy !important; } /* Adding !important forces the browser to overwrite the default style applied by Bootstrap */
</style>

angular ng-repeat in reverse

That's because you are using JSON Object. When you face such problems then change your JSON Object to JSON Array Object.

For Example,

{"India":"IN","America":"US","United Kingdon":"UK"} json object
[{"country":"India","countryId":"IN"},{"country":"America","countryId":"US"},{"country":"United Kingdon","countryId":"UK"}] 

Filtering DataSet

No mention of Merge?

DataSet newdataset = new DataSet();

newdataset.Merge( olddataset.Tables[0].Select( filterstring, sortstring ));

Matplotlib color according to class labels

Assuming that you have your data in a 2d array, this should work:

import numpy
import pylab
xy = numpy.zeros((2, 1000))
xy[0] = range(1000)
xy[1] = range(1000)
colors = [int(i % 23) for i in xy[0]]
pylab.scatter(xy[0], xy[1], c=colors)
pylab.show()

You can also set a cmap attribute to control which colors will appear through use of a colormap; i.e. replace the pylab.scatter line with:

pylab.scatter(xy[0], xy[1], c=colors, cmap=pylab.cm.cool)

A list of color maps can be found here

Iterating over each line of ls -l output

As already mentioned, awk is the right tool for this. If you don't want to use awk, instead of parsing output of "ls -l" line by line, you could iterate over all files and do an "ls -l" for each individual file like this:

for x in * ; do echo `ls -ld $x` ; done

How to add a file to the last commit in git?

If you didn't push the update in remote then the simple solution is remove last local commit using following command: git reset HEAD^. Then add all files and commit again.

Javascript Cookie with no expiration date

If you don't set an expiration date the cookie will expire at the end of the user's session. I recommend using the date right before unix epoch time will extend passed a 32-bit integer. To put that in the cookie you would use document.cookie = "randomCookie=true; expires=Tue, 19 Jan 2038 03:14:07 UTC;, assuming that randomCookie is the cookie you are setting and true is it's respective value.

Convert from lowercase to uppercase all values in all character variables in dataframe

Another alternative is to use a combination of mutate_if() and str_to_uper() function, both from the tidyverse package:

df %>% mutate_if(is.character, str_to_upper) -> df

This will convert all string variables in the data frame to upper case. str_to_lower() do the opposite.

Provisioning Profiles menu item missing from Xcode 5

Stupid as it may sound but all "Provisioning Profiles" re-appear under "Organizer - Devices" once you connect a real device.

How to force C# .net app to run only one instance in Windows?

This is what I use in my application:

static void Main()
{
  bool mutexCreated = false;
  System.Threading.Mutex mutex = new System.Threading.Mutex( true, @"Local\slimCODE.slimKEYS.exe", out mutexCreated );

  if( !mutexCreated )
  {
    if( MessageBox.Show(
      "slimKEYS is already running. Hotkeys cannot be shared between different instances. Are you sure you wish to run this second instance?",
      "slimKEYS already running",
      MessageBoxButtons.YesNo,
      MessageBoxIcon.Question ) != DialogResult.Yes )
    {
      mutex.Close();
      return;
    }
  }

  // The usual stuff with Application.Run()

  mutex.Close();
}

QString to char* conversion

Your string may contain non Latin1 characters, which leads to undefined data. It depends of what you mean by "it deosn't seem to work".

Best way to check for nullable bool in a condition expression (if ...)

Lets check how the comparison with null is defined:

static void Main()
    {
        Console.WriteLine($"null != null  => {null != null}");
        Console.WriteLine($"null == null  => {null == null}");
        Console.WriteLine($"null != true  => {null != true}");
        Console.WriteLine($"null == true  => {null == true}");
        Console.WriteLine($"null != false => {null != false}");
        Console.WriteLine($"null == false => {null == false}");
    }

and the results are:

null != null  => False                                                                                                                                                                                                                                  
null == null  => True                                                                                                                                                                                                                                   
null != true  => True                                                                                                                                                                                                                                   
null == true  => False                                                                                                                                                                                                                                  
null != false => True                                                                                                                                                                                                                                   
null == false => False

So you can safely use:

// check if null or false
if (nullable != true) ...

// check if null or true
if (nullable != false) ...

// check if true or false
if (nullable != null) ...

Is SMTP based on TCP or UDP?

In theory SMTP can be handled by either TCP, UDP, or some 3rd party protocol.

As defined in RFC 821, RFC 2821, and RFC 5321:

SMTP is independent of the particular transmission subsystem and requires only a reliable ordered data stream channel.

In addition, the Internet Assigned Numbers Authority has allocated port 25 for both TCP and UDP for use by SMTP.

In practice however, most if not all organizations and applications only choose to implement the TCP protocol. For example, in Microsoft's port listing port 25 is only listed for TCP and not UDP.


The big difference between TCP and UDP that makes TCP ideal here is that TCP checks to make sure that every packet is received and re-sends them if they are not whereas UDP will simply send packets and not check for receipt. This makes UDP ideal for things like streaming video where every single packet isn't as important as keeping a continuous flow of packets from the server to the client.

Considering SMTP, it makes more sense to use TCP over UDP. SMTP is a mail transport protocol, and in mail every single packet is important. If you lose several packets in the middle of the message the recipient might not even receive the message and if they do they might be missing key information. This makes TCP more appropriate because it ensures that every packet is delivered.

What is the <leader> in a .vimrc file?

Be aware that when you do press your <leader> key you have only 1000ms (by default) to enter the command following it.

This is exacerbated because there is no visual feedback (by default) that you have pressed your <leader> key and vim is awaiting the command; and so there is also no visual way to know when this time out has happened.

If you add set showcmd to your vimrc then you will see your <leader> key appear in the bottom right hand corner of vim (to the left of the cursor location) and perhaps more importantly you will see it disappear when the time out happens.

The length of the timeout can also be set in your vimrc, see :help timeoutlen for more information.

Place cursor at the end of text in EditText

You should be able to achieve that with the help of EditText's method setSelection(), see here

What's the difference between 'git merge' and 'git rebase'?

Personally I don't find the standard diagramming technique very helpful - the arrows always seem to point the wrong way for me. (They generally point towards the "parent" of each commit, which ends up being backwards in time, which is weird).

To explain it in words:

  • When you rebase your branch onto their branch, you tell Git to make it look as though you checked out their branch cleanly, then did all your work starting from there. That makes a clean, conceptually simple package of changes that someone can review. You can repeat this process again when there are new changes on their branch, and you will always end up with a clean set of changes "on the tip" of their branch.
  • When you merge their branch into your branch, you tie the two branch histories together at this point. If you do this again later with more changes, you begin to create an interleaved thread of histories: some of their changes, some of my changes, some of their changes. Some people find this messy or undesirable.

For reasons I don't understand, GUI tools for Git have never made much of an effort to present merge histories more cleanly, abstracting out the individual merges. So if you want a "clean history", you need to use rebase.

I seem to recall having read blog posts from programmers who only use rebase and others that never use rebase.

Example

I'll try explaining this with a just-words example. Let's say other people on your project are working on the user interface, and you're writing documentation. Without rebase, your history might look something like:

Write tutorial
Merge remote-tracking branch 'origin/master' into fixdocs
Bigger buttons
Drop down list
Extend README
Merge remote-tracking branch 'origin/master' into fixdocs
Make window larger
Fix a mistake in howto.md

That is, merges and UI commits in the middle of your documentation commits.

If you rebased your code onto master instead of merging it, it would look like this:

Write tutorial
Extend README
Fix a mistake in howto.md
Bigger buttons
Drop down list
Make window larger

All of your commits are at the top (newest), followed by the rest of the master branch.

(Disclaimer: I'm the author of the "10 things I hate about Git" post referred to in another answer)

Under which circumstances textAlign property works in Flutter?

For maximum flexibility, I usually prefer working with SizedBox like this:

Row(
                                children: <Widget>[
                                  SizedBox(
                                      width: 235,
                                      child: Text('Hey, ')),
                                  SizedBox(
                                      width: 110,
                                      child: Text('how are'),
                                  SizedBox(
                                      width: 10,
                                      child: Text('you?'))
                                ],
                              )

I've experienced problems with text alignment when using alignment in the past, whereas sizedbox always does the work.

How to apply CSS page-break to print a table with lots of rows?

Here is an example:

Via css:

<style>
  .my-table {
    page-break-before: always;
    page-break-after: always;
  }
  .my-table tr {
    page-break-inside: avoid;
  }
</style>

or directly on the element:

<table style="page-break-before: always; page-break-after: always;">
  <tr style="page-break-inside: avoid;">
    ..
  </tr>
</table>

No newline at end of file

For what it's worth, I encountered this when I created an IntelliJ project on a Mac, and then moved the project over to my Windows machine. I had to manually open every file and change the encoding setting at the bottom right of the IntelliJ window. Probably not happening to most if any who read this question but that could have saved me a couple of hours of work...

Programmatically Check an Item in Checkboxlist where text is equal to what I want

//Multiple selection:

          private void clbsec(CheckedListBox clb, string text)
          {
              for (int i = 0; i < clb.Items.Count; i++)
              {
                  if(text == clb.Items[i].ToString())
                  {
                      clb.SetItemChecked(i, true);
                  }
              }
          }

using ==>

clbsec(checkedListBox1,"michael");

or 

clbsec(checkedListBox1,textBox1.Text);

or

clbsec(checkedListBox1,dataGridView1.CurrentCell.Value.toString());

Reverse engineering from an APK file to a project

No software & No too much steps..

Just upload your APK & get your all resources from this site..

https://www.apkdecompilers.com/

This website will decompile the code embedded in APK files and extract all the other assets in the file.

note: I decompile my APK file & get code within one miniute from this website

Update 1:

I found another online decompiler site,

http://www.javadecompilers.com/apk/ - Not working continuously asking for popup blocking

Update 2:

I found apk decompiler app in play store,

https://play.google.com/store/apps/details?id=com.njlabs.showjava

We can decompile the apk files in our android phone. and also we can able to view the java & xml files in this application

Update 3:

We can use another option Analyze APK feature from Android studio 2.2 version

Build -> Analyze APK -> Select your APK -> it give results

enter image description here

How can I set selected option selected in vue.js 2?

<select v-model="challan.warehouse_id">
<option value="">Select Warehouse</option>
<option v-for="warehouse in warehouses" v-bind:value="warehouse.id"  >
   {{ warehouse.name }}
</option>

Here "challan.warehouse_id" come from "challan" object you get from:

editChallan: function() {
    let that = this;
    axios.post('/api/challan_list/get_challan_data', {
    challan_id: that.challan_id
 })
 .then(function (response) {
    that.challan = response.data;
 })
 .catch(function (error) {
    that.errors = error;
  }); 
 }

git stash and git pull

When you have changes on your working copy, from command line do:

git stash 

This will stash your changes and clear your status report

git pull

This will pull changes from upstream branch. Make sure it says fast-forward in the report. If it doesn't, you are probably doing an unintended merge

git stash pop

This will apply stashed changes back to working copy and remove the changes from stash unless you have conflicts. In the case of conflict, they will stay in stash so you can start over if needed.

if you need to see what is in your stash

git stash list

Access denied for user 'root'@'localhost' with PHPMyAdmin

Edit your phpmyadmin config.inc.php file and if you have Password, insert that in front of Password in following code:

$cfg['Servers'][$i]['verbose'] = 'localhost';
$cfg['Servers'][$i]['host'] = 'localhost';
$cfg['Servers'][$i]['port'] = '3306';
$cfg['Servers'][$i]['socket'] = '';
$cfg['Servers'][$i]['connect_type'] = 'tcp';
$cfg['Servers'][$i]['extension'] = 'mysqli';
$cfg['Servers'][$i]['auth_type'] = 'config';
$cfg['Servers'][$i]['user'] = '**your-root-username**';
$cfg['Servers'][$i]['password'] = '**root-password**';
$cfg['Servers'][$i]['AllowNoPassword'] = true;

Visual Studio opens the default browser instead of Internet Explorer

Right-click on an aspx file and choose 'browse with'. I think there's an option there to set as default.

Is it possible to run one logrotate check manually?

If you want to force-run a single specific directory or daemon's log files, you can usually find the configuration in /etc/logrotate.d, and they will work standalone.

Keep in mind that global configuration specified in /etc/logrotate.conf will not apply, so if you do this you should ensure you specify all the options you want in the /etc/logrotate.d/[servicename] config file specifically.

You can try it out with -d to see what would happen:

logrotate -df /etc/logrotate.d/nginx

Then you can run (using nginx as an example):

logrotate -f /etc/logrotate.d/nginx

And the nginx logs alone will be rotated.

How to detect a USB drive has been plugged in?

It is easy to check for removable devices. However, there's no guarantee that it is a USB device:

var drives = DriveInfo.GetDrives()
    .Where(drive => drive.IsReady && drive.DriveType == DriveType.Removable);

This will return a list of all removable devices that are currently accessible. More information:

How to filter an array from all elements of another array

_x000D_
_x000D_
function arr(arr1,arr2){_x000D_
  _x000D_
  function filt(value){_x000D_
    return arr2.indexOf(value) === -1;_x000D_
    }_x000D_
  _x000D_
  return arr1.filter(filt)_x000D_
  }_x000D_
_x000D_
document.getElementById("p").innerHTML = arr([1,2,3,4],[2,4])
_x000D_
<p id="p"></p>
_x000D_
_x000D_
_x000D_

How do I clear the content of a div using JavaScript?

Just Javascript (as requested)

Add this function somewhere on your page (preferably in the <head>)

function clearBox(elementID)
{
    document.getElementById(elementID).innerHTML = "";
}

Then add the button on click event:

<button onclick="clearBox('cart_item')" />

In JQuery (for reference)

If you prefer JQuery you could do:

$("#cart_item").html("");

Show Youtube video source into HTML5 video tag?

Step 1: add &html5=True to your favorite youtube url

Step 2: Find <video/> tag in source

Step 3: Add controls="controls" to video tag: <video controls="controls"..../>

Example:

_x000D_
_x000D_
<video controls="controls" class="video-stream" x-webkit-airplay="allow" data-youtube-id="N9oxmRT2YWw" src="http://v20.lscache8.c.youtube.com/videoplayback?sparams=id%2Cexpire%2Cip%2Cipbits%2Citag%2Cratebypass%2Coc%3AU0hPRVRMVV9FSkNOOV9MRllD&amp;itag=43&amp;ipbits=0&amp;signature=D2BCBE2F115E68C5FF97673F1D797F3C3E3BFB99.59252109C7D2B995A8D51A461FF9A6264879948E&amp;sver=3&amp;ratebypass=yes&amp;expire=1300417200&amp;key=yt1&amp;ip=0.0.0.0&amp;id=37da319914f6616c"></video>
_x000D_
_x000D_
_x000D_

Note there seems to some expire stuff. I don't know how long the src string will work.

Still testing myself.

Edit (July 28, 2011): Note that this video src is specific to the browser you use to retrieve the page source. I think Youtube generates this HTML dynamically (at least currently) so in testing if I copy in Firefox this works in Firefox, but not Chrome, for example.

CSS blur on background image but not on content

backdrop-filter

Unfortunately Mozilla has really dropped the ball and taken it's time with the feature. I'm personally hoping it makes it in to the next Firefox ESR as that is what the next major version of Waterfox will use.

MDN (Mozilla Developer Network) article: https://developer.mozilla.org/en-US/docs/Web/CSS/backdrop-filter

Mozilla implementation: https://bugzilla.mozilla.org/show_bug.cgi?id=1178765

From the MDN documentation page:

/* URL to SVG filter */
backdrop-filter: url(commonfilters.svg#filter);

/* <filter-function> values */
backdrop-filter: blur(2px);
backdrop-filter: brightness(60%);
backdrop-filter: contrast(40%);
backdrop-filter: drop-shadow(4px 4px 10px blue);
backdrop-filter: grayscale(30%);
backdrop-filter: hue-rotate(120deg);
backdrop-filter: invert(70%);
backdrop-filter: opacity(20%);
backdrop-filter: sepia(90%);
backdrop-filter: saturate(80%);

/* Multiple filters */
backdrop-filter: url(filters.svg#filter) blur(4px) saturate(150%);

Difference between adjustResize and adjustPan in android?

As doc says also keep in mind the correct value combination:

The setting must be one of the values listed in the following table, or a combination of one "state..." value plus one "adjust..." value. Setting multiple values in either group — multiple "state..." values, for example — has undefined results. Individual values are separated by a vertical bar (|). For example:

<activity android:windowSoftInputMode="stateVisible|adjustResize" . . . >

OpenMP set_num_threads() is not working

Try setting your num_threads inside your omp parallel code, it worked for me. This will give output as 4

#pragma omp parallel
{
   omp_set_num_threads(4);
   int id = omp_get_num_threads();
   #pragma omp for
   for (i = 0:n){foo(A);}
}

printf("Number of threads: %d", id);

Different color for each bar in a bar chart; ChartJS

Here, I solved this issue by making two functions.

1. dynamicColors() to generate random color

function dynamicColors() {
    var r = Math.floor(Math.random() * 255);
    var g = Math.floor(Math.random() * 255);
    var b = Math.floor(Math.random() * 255);
    return "rgba(" + r + "," + g + "," + b + ", 0.5)";
}

2. poolColors() to create array of colors

function poolColors(a) {
    var pool = [];
    for(i = 0; i < a; i++) {
        pool.push(dynamicColors());
    }
    return pool;
}

Then, just pass it

datasets: [{
    data: arrData,
    backgroundColor: poolColors(arrData.length),
    borderColor: poolColors(arrData.length),
    borderWidth: 1
}]

Get only part of an Array in Java?

The length of an array in Java is immutable. So, you need to copy the desired part as a new array.
Use copyOfRange method from java.util.Arrays class:

int[] newArray = Arrays.copyOfRange(oldArray, startIndex, endIndex);

startIndex is the initial index of the range to be copied, inclusive.
endIndex is the final index of the range to be copied, exclusive. (This index may lie outside the array)

E.g.:

   //index   0   1   2   3   4
int[] arr = {10, 20, 30, 40, 50};
Arrays.copyOfRange(arr, 0, 2);          // returns {10, 20}
Arrays.copyOfRange(arr, 1, 4);          // returns {20, 30, 40}
Arrays.copyOfRange(arr, 2, arr.length); // returns {30, 40, 50} (length = 5)

Remove Item from ArrayList

Try it this way,

ArrayList<String> List_Of_Array = new ArrayList<String>();
List_Of_Array.add("A");
List_Of_Array.add("B");
List_Of_Array.add("C");
List_Of_Array.add("D");
List_Of_Array.add("E");
List_Of_Array.add("F");
List_Of_Array.add("G");
List_Of_Array.add("H");

int i[] = {5,3,1};

for (int j = 0; j < i.length; j++) {
    List_Of_Array.remove(i[j]);
}

Colouring plot by factor in R

The command palette tells you the colours and their order when col = somefactor. It can also be used to set the colours as well.

palette()
[1] "black"   "red"     "green3"  "blue"    "cyan"    "magenta" "yellow"  "gray"   

In order to see that in your graph you could use a legend.

legend('topright', legend = levels(iris$Species), col = 1:3, cex = 0.8, pch = 1)

You'll notice that I only specified the new colours with 3 numbers. This will work like using a factor. I could have used the factor originally used to colour the points as well. This would make everything logically flow together... but I just wanted to show you can use a variety of things.

You could also be specific about the colours. Try ?rainbow for starters and go from there. You can specify your own or have R do it for you. As long as you use the same method for each you're OK.

Deprecation warning in Moment.js - Not in a recognized ISO format

use moment in your function like this

 moment(new Date(date)).format('MM/DD/YYYY')

VBA: How to delete filtered rows in Excel?

As an alternative to using UsedRange or providing an explicit range address, the AutoFilter.Range property can also specify the affected range.

ActiveSheet.AutoFilter.Range.Offset(1,0).Rows.SpecialCells(xlCellTypeVisible).Delete(xlShiftUp)

As used here, Offset causes the first row after the AutoFilter range to also be deleted. In order to avoid that, I would try using .Resize() after .Offset().

How to declare an ArrayList with values?

Try this!

List<String> x = new ArrayList<String>(Arrays.asList("xyz", "abc"));

It's a good practice to declare the ArrayList with interface List if you don't have to invoke the specific methods.

DataTables: Cannot read property 'length' of undefined

This is really late to the party, but none of the solutions above worked for me. I didn't want the "Found total xxx records" so I added info:false to the config. When I removed that everything worked.

I should note that the first page loaded fine. When I hit next, the second page loaded, but immediately threw the above console error

Spring Boot Rest Controller how to return different HTTP status codes?

There are different ways to return status code, 1 : RestController class should extends BaseRest class, in BaseRest class we can handle exception and return expected error codes. for example :

@RestController
@RequestMapping
class RestController extends BaseRest{

}

@ControllerAdvice
public class BaseRest {
@ExceptionHandler({Exception.class,...})
    @ResponseStatus(value=HttpStatus.INTERNAL_SERVER_ERROR)
    public ErrorModel genericError(HttpServletRequest request, 
            HttpServletResponse response, Exception exception) {
        
        ErrorModel error = new ErrorModel();
        resource.addError("error code", exception.getLocalizedMessage());
        return error;
    }

Scale iFrame css width 100% like an image

I suppose this is a cleaner approach. It works with inline height and width properties (I set random value in the fiddle to prove that) and with CSS max-width property.

HTML:

<div class="wrapper">
    <div class="h_iframe">
        <iframe height="2" width="2" src="http://www.youtube.com/embed/WsFWhL4Y84Y" frameborder="0" allowfullscreen></iframe>
    </div>
    <p>Please scale the "result" window to notice the effect.</p>
</div>

CSS:

html,body        {height: 100%;}
.wrapper         {width: 80%; max-width: 600px; height: 100%; margin: 0 auto; background: #CCC}
.h_iframe        {position: relative; padding-top: 56%;}
.h_iframe iframe {position: absolute; top: 0; left: 0; width: 100%; height: 100%;}

http://jsfiddle.net/7WRHM/1001/

C# Creating an array of arrays

What you need to do is this:

int[] list1 = new int[4] { 1, 2, 3, 4};
int[] list2 = new int[4] { 5, 6, 7, 8};
int[] list3 = new int[4] { 1, 3, 2, 1 };
int[] list4 = new int[4] { 5, 4, 3, 2 };

int[][] lists = new int[][] {  list1 ,  list2 ,  list3 ,  list4  };

Another alternative would be to create a List<int[]> type:

List<int[]> data=new List<int[]>(){list1,list2,list3,list4};

Return multiple values to a method caller

Future version of C# is going to include named tuples. Have a look at this channel9 session for the demo https://channel9.msdn.com/Events/Build/2016/B889

Skip to 13:00 for the tuple stuff. This will allow stuff like:

(int sum, int count) Tally(IEnumerable<int> list)
{
// calculate stuff here
return (0,0)
}

int resultsum = Tally(numbers).sum

(incomplete example from video)

How to suspend/resume a process in Windows?

PsSuspend command line utility from SysInternals suite. It suspends / resumes a process by its id.

How to run a JAR file

I have this folder structure:

D:\JavaProjects\OlivePressApp\com\lynda\olivepress\Main.class D:\JavaProjects\OlivePressApp\com\lynda\olivepress\press\OlivePress.class D:\JavaProjects\OlivePressApp\com\lynda\olivepress\olives\Kalamata.class D:\JavaProjects\OlivePressApp\com\lynda\olivepress\olives\Ligurian.class D:\JavaProjects\OlivePressApp\com\lynda\olivepress\olives\Olive.class

Main.class is in package com.lynda.olivepress

There are two other packages:

com.lynda.olivepress.press

com.lynda.olivepress.olive

1) Create a file named "Manifest.txt" with Two Lines, First with Main-Class and a Second Empty Line.

Main-Class: com.lynda.olivepress.Main

D:\JavaProjects\OlivePressApp\ Manifest.txt

2) Create JAR with Manifest and Main-Class Entry Point

D:\JavaProjects\OlivePressApp>jar cfm OlivePressApp.jar Manifest.txt com/lynda/olivepress/Main.class com/lynda/olivepress/*

3) Run JAR

java -jar OlivePressApp.jar

Note: com/lynda/olivepress/* means including the other two packages mentioned above, before point 1)

Angular.js and HTML5 date input value -- how to get Firefox to show a readable date value in a date input?

Check this fully functional directive for MEAN.JS (Angular.js, bootstrap, Express.js and MongoDb)

Based on @Blackhole ´s response, we just finished it to be used with mongodb and express.

It will allow you to save and load dates from a mongoose connector

Hope it Helps!!

angular.module('myApp')
.directive(
  'dateInput',
  function(dateFilter) {
    return {
      require: 'ngModel',
      template: '<input type="date" class="form-control"></input>',
      replace: true,
      link: function(scope, elm, attrs, ngModelCtrl) {
        ngModelCtrl.$formatters.unshift(function (modelValue) {
          return dateFilter(modelValue, 'yyyy-MM-dd');
        });

        ngModelCtrl.$parsers.push(function(modelValue){
           return angular.toJson(modelValue,true)
          .substring(1,angular.toJson(modelValue).length-1);
        })

      }
    };
  });

The JADE/HTML:

div(date-input, ng-model="modelDate")

How to recover MySQL database from .myd, .myi, .frm files

Note that if you want to rebuild the MYI file then the correct use of REPAIR TABLE is:

REPAIR TABLE sometable USE_FRM;

Otherwise you will probably just get another error.

How can I programmatically determine if my app is running in the iphone simulator?

if nothing worked, try this

public struct Platform {

    public static var isSimulator: Bool {
        return TARGET_OS_SIMULATOR != 0 // Use this line in Xcode 7 or newer
    }

}

Trim a string in C

Easiest thing to do is a simple loop. I'm going to assume that you want the trimmed string returned in place.

char *
strTrim(char * s){
    int ix, jx;
    int len ;
    char * buf 
    len = strlen(s);  /* possibly should use strnlen */
    buf = (char *) malloc(strlen(s)+1);

    for(ix=0, jx=0; ix < len; ix++){
       if(!isspace(s[ix]))
          buf[jx++] = s[ix];

    buf[jx] = '\0';
    strncpy(s, buf, jx);  /* always looks as far as the null, but who cares? */
    free(buf);            /* no good leak goes unpunished */
    return s;             /* modifies s in place *and* returns it for swank */
 }

This gets rid of embedded blanks too, if String.Trim doesn't then it needs a bit more logic.

How to use HTTP GET in PowerShell?

In PowerShell v3, have a look at the Invoke-WebRequest and Invoke-RestMethod e.g.:

$msg = Read-Host -Prompt "Enter message"
$encmsg = [System.Web.HttpUtility]::UrlEncode($msg)
Invoke-WebRequest -Uri "http://smsserver/SNSManager/msgSend.jsp?uid&to=smartsms:*+001XXXXXX&msg=$encmsg&encoding=windows-1255"

MongoDB and "joins"

It's no join since the relationship will only be evaluated when needed. A join (in a SQL database) on the other hand will resolve relationships and return them as if they were a single table (you "join two tables into one").

You can read more about DBRef here: http://docs.mongodb.org/manual/applications/database-references/

There are two possible solutions for resolving references. One is to do it manually, as you have almost described. Just save a document's _id in another document's other_id, then write your own function to resolve the relationship. The other solution is to use DBRefs as described on the manual page above, which will make MongoDB resolve the relationship client-side on demand. Which solution you choose does not matter so much because both methods will resolve the relationship client-side (note that a SQL database resolves joins on the server-side).

How do I make JavaScript beep?

Using Houshalter's suggestion, I made this simple tone synthesizer demo.

Screenshot

Here is a screenshot. Try the live demo further down in this Answer (click Run code snippet).

screenshot of live demo available further down in this Answer

Demo code

_x000D_
_x000D_
audioCtx = new(window.AudioContext || window.webkitAudioContext)();_x000D_
_x000D_
show();_x000D_
_x000D_
function show() {_x000D_
  frequency = document.getElementById("fIn").value;_x000D_
  document.getElementById("fOut").innerHTML = frequency + ' Hz';_x000D_
_x000D_
  switch (document.getElementById("tIn").value * 1) {_x000D_
    case 0: type = 'sine'; break;_x000D_
    case 1: type = 'square'; break;_x000D_
    case 2: type = 'sawtooth'; break;_x000D_
    case 3: type = 'triangle'; break;_x000D_
  }_x000D_
  document.getElementById("tOut").innerHTML = type;_x000D_
_x000D_
  volume = document.getElementById("vIn").value / 100;_x000D_
  document.getElementById("vOut").innerHTML = volume;_x000D_
_x000D_
  duration = document.getElementById("dIn").value;_x000D_
  document.getElementById("dOut").innerHTML = duration + ' ms';_x000D_
}_x000D_
_x000D_
function beep() {_x000D_
  var oscillator = audioCtx.createOscillator();_x000D_
  var gainNode = audioCtx.createGain();_x000D_
_x000D_
  oscillator.connect(gainNode);_x000D_
  gainNode.connect(audioCtx.destination);_x000D_
_x000D_
  gainNode.gain.value = volume;_x000D_
  oscillator.frequency.value = frequency;_x000D_
  oscillator.type = type;_x000D_
_x000D_
  oscillator.start();_x000D_
_x000D_
  setTimeout(_x000D_
    function() {_x000D_
      oscillator.stop();_x000D_
    },_x000D_
    duration_x000D_
  );_x000D_
};
_x000D_
frequency_x000D_
<input type="range" id="fIn" min="40" max="6000" oninput="show()" />_x000D_
<span id="fOut"></span><br>_x000D_
type_x000D_
<input type="range" id="tIn" min="0" max="3" oninput="show()" />_x000D_
<span id="tOut"></span><br>_x000D_
volume_x000D_
<input type="range" id="vIn" min="0" max="100" oninput="show()" />_x000D_
<span id="vOut"></span><br>_x000D_
duration_x000D_
<input type="range" id="dIn" min="1" max="5000" oninput="show()" />_x000D_
<span id="dOut"></span>_x000D_
<br>_x000D_
<button onclick='beep();'>Play</button>
_x000D_
_x000D_
_x000D_

You can clone and tweak the code here: Tone synthesizer demo on JS Bin

Have fun!

Compatible browsers:

  • Chrome mobile & desktop
  • Firefox mobile & desktop
  • Opera mobile, mini & desktop
  • Android browser
  • Microsoft Edge browser
  • Safari on iPhone or iPad

Not Compatible

  • Internet Explorer version 11 (but does work on the Edge browser)

How to pass variable number of arguments to a PHP function

If you have your arguments in an array, you might be interested by the call_user_func_array function.

If the number of arguments you want to pass depends on the length of an array, it probably means you can pack them into an array themselves -- and use that one for the second parameter of call_user_func_array.

Elements of that array you pass will then be received by your function as distinct parameters.


For instance, if you have this function :

function test() {
  var_dump(func_num_args());
  var_dump(func_get_args());
}

You can pack your parameters into an array, like this :

$params = array(
  10,
  'glop',
  'test',
);

And, then, call the function :

call_user_func_array('test', $params);

This code will the output :

int 3

array
  0 => int 10
  1 => string 'glop' (length=4)
  2 => string 'test' (length=4)

ie, 3 parameters ; exactly like iof the function was called this way :

test(10, 'glop', 'test');

Pandas: Setting no. of max rows

Set display.max_rows:

pd.set_option('display.max_rows', 500)

For older versions of pandas (<=0.11.0) you need to change both display.height and display.max_rows.

pd.set_option('display.height', 500)
pd.set_option('display.max_rows', 500)

See also pd.describe_option('display').

You can set an option only temporarily for this one time like this:

from IPython.display import display
with pd.option_context('display.max_rows', 100, 'display.max_columns', 10):
    display(df) #need display to show the dataframe when using with in jupyter
    #some pandas stuff

You can also reset an option back to its default value like this:

pd.reset_option('display.max_rows')

And reset all of them back:

pd.reset_option('all')

Dictionary text file

There's also WordNet. Its data files format are well-documented.
I used it for building an embeddable dictionary library for iOS developers (www.lexicontext.com) and also in one of my apps.

How to iterate over a string in C?

sizeof(source) returns sizeof a pointer as source is declared as char *. Correct way to use it is strlen(source).

Next:

printf("%s",source[i]); 

expects string. i.e %s expects string but you are iterating in a loop to print each character. Hence use %c.

However your way of accessing(iterating) a string using the index i is correct and hence there are no other issues in it.

Simple way to copy or clone a DataRow?

You can use ImportRow method to copy Row from DataTable to DataTable with the same schema:

var row = SourceTable.Rows[RowNum];
DestinationTable.ImportRow(row);

Update:

With your new Edit, I believe:

var desRow = dataTable.NewRow();
var sourceRow = dataTable.Rows[rowNum];
desRow.ItemArray = sourceRow.ItemArray.Clone() as object[];

will work

Ignore cells on Excel line graph

In Excel 2007 you have the option to show empty cells as gaps, zero or connect data points with a line (I assume it's similar for Excel 2010):

enter image description here

If none of these are optimal and you have a "chunk" of data points (or even single ones) missing, you can group-and-hide them, which will remove them from the chart.

Before hiding:

enter image description here

After hiding:

enter image description here

How to format a float in javascript?

function trimNumber(num, len) {
  const modulu_one = 1;
  const start_numbers_float=2;
  var int_part = Math.trunc(num);
  var float_part = String(num % modulu_one);
      float_part = float_part.slice(start_numbers_float, start_numbers_float+len);
  return int_part+'.'+float_part;
}

How to make the checkbox unchecked by default always

One quick solution that came to mind :-

<input type="checkbox" id="markitem" name="markitem" value="1" onchange="GetMarkedItems(1)">
<label for="markitem" style="position:absolute; top:1px; left:165px;">&nbsp</label>
<!-- Fire the below javascript everytime the page reloads -->
<script type=text/javascript>
  document.getElementById("markitem").checked = false;
</script>
<!-- Tested on Latest FF, Chrome, Opera and IE. -->

Why does CSV file contain a blank line in between each data line when outputting with Dictwriter in Python

From http://docs.python.org/library/csv.html#csv.writer:

If csvfile is a file object, it must be opened with the ‘b’ flag on platforms where that makes a difference.

In other words, when opening the file you pass 'wb' as opposed to 'w'.
You can also use a with statement to close the file when you're done writing to it.
Tested example below:

from __future__ import with_statement # not necessary in newer versions
import csv
headers=['id', 'year', 'activity', 'lineitem', 'datum']
with open('file3.csv','wb') as fou: # note: 'wb' instead of 'w'
    output = csv.DictWriter(fou,delimiter=',',fieldnames=headers)
    output.writerow(dict((fn,fn) for fn in headers))
    output.writerows(rows)

How to add data validation to a cell using VBA

Use this one:

Dim ws As Worksheet
Dim range1 As Range, rng As Range
'change Sheet1 to suit
Set ws = ThisWorkbook.Worksheets("Sheet1")

Set range1 = ws.Range("A1:A5")
Set rng = ws.Range("B1")

With rng.Validation
    .Delete 'delete previous validation
    .Add Type:=xlValidateList, AlertStyle:=xlValidAlertStop, _
        Formula1:="='" & ws.Name & "'!" & range1.Address
End With

Note that when you're using Dim range1, rng As range, only rng has type of Range, but range1 is Variant. That's why I'm using Dim range1 As Range, rng As Range.
About meaning of parameters you can read is MSDN, but in short:

  • Type:=xlValidateList means validation type, in that case you should select value from list
  • AlertStyle:=xlValidAlertStop specifies the icon used in message boxes displayed during validation. If user enters any value out of list, he/she would get error message.
  • in your original code, Operator:= xlBetween is odd. It can be used only if two formulas are provided for validation.
  • Formula1:="='" & ws.Name & "'!" & range1.Address for list data validation provides address of list with values (in format =Sheet!A1:A5)

differences between using wmode="transparent", "opaque", or "window" for an embedded object on a webpage

Here is some weak adobe documentation on different flash 9 wmode settings.

A note of caution on wmode transparent is here in the adobe bug trac.

And new for flash 10, are two new wmodes: gpu and direct. Please refer to Adobe Knowledge Base about wmode.

How to show Page Loading div until the page has finished loading?

My blog will work 100 percent.

_x000D_
_x000D_
function showLoader()_x000D_
{_x000D_
    $(".loader").fadeIn("slow");_x000D_
}_x000D_
function hideLoader()_x000D_
{_x000D_
    $(".loader").fadeOut("slow");_x000D_
}
_x000D_
.loader {_x000D_
    position: fixed;_x000D_
    left: 0px;_x000D_
    top: 0px;_x000D_
    width: 100%;_x000D_
    height: 100%;_x000D_
    z-index: 9999;_x000D_
    background: url('pageLoader2.gif') 50% 50% no-repeat rgb(249,249,249);_x000D_
    opacity: .8;_x000D_
}
_x000D_
<div class="loader">
_x000D_
_x000D_
_x000D_

Git in Visual Studio - add existing project?

First create a 'Solution Folder' with the desired relative path. Note that Visual Studio 2012 does not create a system folder with the same relative path.

Now inside that 'Solution Folder' add a new project, but you must be careful when defining it that the relative path in the system matches the relative path of your new 'Solution Folder'. If the system folder you want does not exist, Visual Studio 2012 will now create it for the new project. (As noted above, it does not do this when you add a new 'Solution Folder'.)

If you want to add an existing file with the matching relative path, you must first create the file in the matching system relative path, from outside of Visual Studio. Then you can Add existing file in Visual Studio.

How do you build a Singleton in Dart?

Hello what about something like this? Very simple implementation, Injector itself is singleton and also added classes into it. Of course can be extended very easily. If you are looking for something more sophisticated check this package: https://pub.dartlang.org/packages/flutter_simple_dependency_injection

void main() {  
  Injector injector = Injector();
  injector.add(() => Person('Filip'));
  injector.add(() => City('New York'));

  Person person =  injector.get<Person>(); 
  City city =  injector.get<City>();

  print(person.name);
  print(city.name);
}

class Person {
  String name;

  Person(this.name);
}

class City {
  String name;

  City(this.name);
}


typedef T CreateInstanceFn<T>();

class Injector {
  static final Injector _singleton =  Injector._internal();
  final _factories = Map<String, dynamic>();

  factory Injector() {
    return _singleton;
  }

  Injector._internal();

  String _generateKey<T>(T type) {
    return '${type.toString()}_instance';
  }

  void add<T>(CreateInstanceFn<T> createInstance) {
    final typeKey = _generateKey(T);
    _factories[typeKey] = createInstance();
  }

  T get<T>() {
    final typeKey = _generateKey(T);
    T instance = _factories[typeKey];
    if (instance == null) {
      print('Cannot find instance for type $typeKey');
    }

    return instance;
  }
}

MySQL: Insert datetime into other datetime field

If you don't need the DATETIME value in the rest of your code, it'd be more efficient, simple and secure to use an UPDATE query with a sub-select, something like

UPDATE products SET t=(SELECT f FROM products WHERE id=17) WHERE id=42;

or in case it's in the same row in a single table, just

UPDATE products SET t=f WHERE id=42;

How to restart VScode after editing extension's config?

  1. Open the Command Palette

    Ctrl + Shift + P

  2. Then type:

    Reload Window
    

MySQL DAYOFWEEK() - my week begins with monday

Try to use the WEEKDAY() function.

Returns the weekday index for date (0 = Monday, 1 = Tuesday, … 6 = Sunday).

scale Image in an UIButton to AspectFit?

If you really want to scale an image, do it, but you should resize it before using it. Resizing it at run time will just lose CPU cycles.

This is the category I'm using to scale an image :

UIImage+Extra.h

@interface UIImage (Extras)
- (UIImage *)imageByScalingProportionallyToSize:(CGSize)targetSize;
@end;

UIImage+Extra.m

@implementation UIImage (Extras)

- (UIImage *)imageByScalingProportionallyToSize:(CGSize)targetSize {

UIImage *sourceImage = self;
UIImage *newImage = nil;

CGSize imageSize = sourceImage.size;
CGFloat width = imageSize.width;
CGFloat height = imageSize.height;

CGFloat targetWidth = targetSize.width;
CGFloat targetHeight = targetSize.height;

CGFloat scaleFactor = 0.0;
CGFloat scaledWidth = targetWidth;
CGFloat scaledHeight = targetHeight;

CGPoint thumbnailPoint = CGPointMake(0.0,0.0);

if (!CGSizeEqualToSize(imageSize, targetSize)) {

        CGFloat widthFactor = targetWidth / width;
        CGFloat heightFactor = targetHeight / height;

        if (widthFactor < heightFactor) 
                scaleFactor = widthFactor;
        else
                scaleFactor = heightFactor;

        scaledWidth  = width * scaleFactor;
        scaledHeight = height * scaleFactor;

        // center the image

        if (widthFactor < heightFactor) {
                thumbnailPoint.y = (targetHeight - scaledHeight) * 0.5; 
        } else if (widthFactor > heightFactor) {
                thumbnailPoint.x = (targetWidth - scaledWidth) * 0.5;
        }
}


// this is actually the interesting part:

UIGraphicsBeginImageContextWithOptions(targetSize, NO, 0);

CGRect thumbnailRect = CGRectZero;
thumbnailRect.origin = thumbnailPoint;
thumbnailRect.size.width  = scaledWidth;
thumbnailRect.size.height = scaledHeight;

[sourceImage drawInRect:thumbnailRect];

newImage = UIGraphicsGetImageFromCurrentImageContext();
UIGraphicsEndImageContext();

if(newImage == nil) NSLog(@"could not scale image");


return newImage ;
}

@end

You can use it to the size you want. Like :

[self.itemImageButton setImage:[stretchImage imageByScalingProportionallyToSize:CGSizeMake(20,20)]];

Is ASCII code 7-bit or 8-bit?

ASCII encoding is 7-bit, but in practice, characters encoded in ASCII are not stored in groups of 7 bits. Instead, one ASCII is stored in a byte, with the MSB usually set to 0 (yes, it's wasted in ASCII).

You can verify this by inputting a string in the ASCII character set in a text editor, setting the encoding to ASCII, and viewing the binary/hex:
enter image description here

Aside: the use of (strictly) ASCII encoding is now uncommon, in favor of UTF-8 (which does not waste the MSB mentioned above - in fact, an MSB of 1 indicates the code point is encoded with more than 1 byte).

How to count number of records per day?

You could also try this:

SELECT DISTINCT (DATE(dateadded)) AS unique_date, COUNT(*) AS amount
FROM table
GROUP BY unique_date
ORDER BY unique_date ASC

Batch files: List all files in a directory with relative paths

You could simply get the character length of the current directory, and remove them from your absolute list

setlocal EnableDelayedExpansion
for /L %%n in (1 1 500) do if "!__cd__:~%%n,1!" neq "" set /a "len=%%n+1"
setlocal DisableDelayedExpansion
for /r . %%g in (*.log) do (
  set "absPath=%%g"
  setlocal EnableDelayedExpansion
  set "relPath=!absPath:~%len%!"
  echo(!relPath!
  endlocal
)

Guid is all 0's (zeros)?

Can't tell you how many times this has caught. me.

Guid myGuid = Guid.NewGuid(); 

How to change icon on Google map marker

try this

var locations = [
        ['San Francisco: Power Outage', 37.7749295, -122.4194155,'http://labs.google.com/ridefinder/images/mm_20_purple.png'],
        ['Sausalito', 37.8590937, -122.4852507,'http://labs.google.com/ridefinder/images/mm_20_red.png'],
        ['Sacramento', 38.5815719, -121.4943996,'http://labs.google.com/ridefinder/images/mm_20_green.png'],
        ['Soledad', 36.424687, -121.3263187,'http://labs.google.com/ridefinder/images/mm_20_blue.png'],
        ['Shingletown', 40.4923784, -121.8891586,'http://labs.google.com/ridefinder/images/mm_20_yellow.png']
    ];



//inside the loop
marker = new google.maps.Marker({
                position: new google.maps.LatLng(locations[i][1], locations[i][2]),
                map: map,
                icon: locations[i][3]
            });

canvas.toDataURL() SecurityError

This method will prevent you from getting an 'Access-Control-Allow-Origin' error from the server you are accessing to.

var img = new Image();
var timestamp = new Date().getTime();
img.setAttribute('crossOrigin', 'anonymous');
img.src = url + '?' + timestamp;

Plot multiple lines in one graph

You should bring your data into long (i.e. molten) format to use it with ggplot2:

library("reshape2")
mdf <- melt(mdf, id.vars="Company", value.name="value", variable.name="Year")

And then you have to use aes( ... , group = Company ) to group them:

ggplot(data=mdf, aes(x=Year, y=value, group = Company, colour = Company)) +
    geom_line() +
    geom_point( size=4, shape=21, fill="white")

enter image description here

Is it good practice to make the constructor throw an exception?

This is totally valid, I do it all the time. I usually use IllegalArguemntException if it is a result of parameter checking.

In this case I wouldn't suggest asserts because they are turned off in a deployment build and you always want to stop this from happening, but they are valid if your group does ALL it's testing with asserts turned on and you think the chance of missing a parameter problem at runtime is more acceptable than throwing an exception that is maybe more likely to cause a runtime crash.

Also, an assert would be more difficult for the caller to trap, this is easy.

You probably want to list it as a "throws" in your method's javadocs along with the reason so that callers aren't surprised.

Run javascript script (.js file) in mongodb including another file inside js

Yes you can. The default location for script files is data/db

If you put any script there you can call it as

load("myjstest.js")      // or 
load("/data/db/myjstest.js")

Check the current number of connections to MongoDb

db.runCommand( { "connPoolStats" : 1 } )

{
    "numClientConnections" : 0,
    "numAScopedConnections" : 0,
    "totalInUse" : 0,
    "totalAvailable" : 0,
    "totalCreated" : 0,
    "hosts" : {

    },
    "replicaSets" : {

    },
    "ok" : 1
}

How to add property to object in PHP >= 5.3 strict mode without generating error

If you absolutely have to add the property to the object, I believe you could cast it as an array, add your property (as a new array key), then cast it back as an object. The only time you run into stdClass objects (I believe) is when you cast an array as an object or when you create a new stdClass object from scratch (and of course when you json_decode() something - silly me for forgetting!).

Instead of:

$foo = new StdClass();
$foo->bar = '1234';

You'd do:

$foo = array('bar' => '1234');
$foo = (object)$foo;

Or if you already had an existing stdClass object:

$foo = (array)$foo;
$foo['bar'] = '1234';
$foo = (object)$foo;

Also as a 1 liner:

$foo = (object) array_merge( (array)$foo, array( 'bar' => '1234' ) );

How to detect when an @Input() value changes in Angular?

I just want to add that there is another Lifecycle hook called DoCheck that is useful if the @Input value is not a primitive value.

I have an Array as an Input so this does not fire the OnChanges event when the content changes (because the checking that Angular does is 'simple' and not deep so the Array is still an Array, even though the content on the Array has changed).

I then implement some custom checking code to decide if I want to update my view with the changed Array.

JavaScript ternary operator example with functions

I know question is already answered.

But let me add one point here. This is not only case of true or false. See below:

var val="Do";

Var c= (val == "Do" || val == "Done")
          ? 7
          : 0

Here if val is Do or Done then c will be 7 else it will be zero. In this case c will be 7.

This is actually another perspective of this operator.

Setting active profile and config location from command line in spring boot

-Dspring.profiles.active=staging -Dspring.config.location=C:\Config

is not correct.

should be:

--spring.profiles.active=staging --spring.config.location=C:\Config

How to use environment variables in docker compose

The following is applicable for docker-compose 3.x Set environment variables inside the container

method - 1 Straight method

web:
  environment:
    - DEBUG=1
      POSTGRES_PASSWORD: 'postgres'
      POSTGRES_USER: 'postgres'

method - 2 The “.env” file

Create a .env file in the same location as the docker-compose.yml

$ cat .env
TAG=v1.5
POSTGRES_PASSWORD: 'postgres'

and your compose file will be like

$ cat docker-compose.yml
version: '3'
services:
  web:
    image: "webapp:${TAG}"
    postgres_password: "${POSTGRES_PASSWORD}"

source

How do I set an ASP.NET Label text from code behind on page load?

I know this was posted a long while ago, and it has been marked answered, but to me, the selected answer was not answering the question I thought the user was posing. It seemed to me he was looking for the approach one can take in ASP .Net that corresponds to his inline data binding previously performed in php.

Here was his php:

<p>Here is the username: <?php echo GetUserName(); ?></p>

Here is what one would do in ASP .Net:

<p>Here is the username: <%= GetUserName() %></p>

Do you need to dispose of objects and set them to null?

I agree with the common answer here that yes you should dispose and no you generally shouldn't set the variable to null... but I wanted to point out that dispose is NOT primarily about memory management. Yes, it can help (and sometimes does) with memory management, but it's primary purpose is to give you deterministic releasing of scarce resources.

For example, if you open a hardware port (serial for example), a TCP/IP socket, a file (in exclusive access mode) or even a database connection you have now prevented any other code from using those items until they are released. Dispose generally releases these items (along with GDI and other "os" handles etc. which there are 1000's of available, but are still limited overall). If you don't call dipose on the owner object and explicitly release these resources, then try to open the same resource again in the future (or another program does) that open attempt will fail because your undisposed, uncollected object still has the item open. Of course, when the GC collects the item (if the Dispose pattern has been implemented correctly) the resource will get released... but you don't know when that will be, so you don't know when it's safe to re-open that resource. This is the primary issue Dispose works around. Of course, releasing these handles often releases memory too, and never releasing them may never release that memory... hence all the talk about memory leaks, or delays in memory clean up.

I have seen real world examples of this causing problems. For instance, I have seen ASP.Net web applications that eventually fail to connect to the database (albeit for short periods of time, or until the web server process is restarted) because the sql server 'connection pool is full'... i.e, so many connections have been created and not explicitly released in so short a period of time that no new connections can be created and many of the connections in the pool, although not active, are still referenced by undiposed and uncollected objects and so can't be reused. Correctly disposing the database connections where necessary ensures this problem doesn't happen (at least not unless you have very high concurrent access).

failed to open stream: HTTP wrapper does not support writeable connections

Instead of doing file_put_contents(***WebSiteURL***...) you need to use the server path to /cache/lang/file.php (e.g. /home/content/site/folders/filename.php).

You cannot open a file over HTTP and expect it to be written. Instead you need to open it using the local path.

How to tell whether a point is to the right or left side of a line

Assuming the points are (Ax,Ay) (Bx,By) and (Cx,Cy), you need to compute:

(Bx - Ax) * (Cy - Ay) - (By - Ay) * (Cx - Ax)

This will equal zero if the point C is on the line formed by points A and B, and will have a different sign depending on the side. Which side this is depends on the orientation of your (x,y) coordinates, but you can plug test values for A,B and C into this formula to determine whether negative values are to the left or to the right.

Read a file one line at a time in node.js?

Since Node.js v0.12 and as of Node.js v4.0.0, there is a stable readline core module. Here's the easiest way to read lines from a file, without any external modules:

const fs = require('fs');
const readline = require('readline');

async function processLineByLine() {
  const fileStream = fs.createReadStream('input.txt');

  const rl = readline.createInterface({
    input: fileStream,
    crlfDelay: Infinity
  });
  // Note: we use the crlfDelay option to recognize all instances of CR LF
  // ('\r\n') in input.txt as a single line break.

  for (const line of rl) {
    // Each line in input.txt will be successively available here as `line`.
    console.log(`Line from file: ${line}`);
  }
}

processLineByLine();

Or alternatively:

var lineReader = require('readline').createInterface({
  input: require('fs').createReadStream('file.in')
});

lineReader.on('line', function (line) {
  console.log('Line from file:', line);
});

The last line is read correctly (as of Node v0.12 or later), even if there is no final \n.

UPDATE: this example has been added to Node's API official documentation.

Embedding Windows Media Player for all browsers

Use the following. It works in Firefox and Internet Explorer.

        <object id="MediaPlayer1" width="690" height="500" classid="CLSID:22D6F312-B0F6-11D0-94AB-0080C74C7E95"
            codebase="http://activex.microsoft.com/activex/controls/mplayer/en/nsmp2inf.cab#Version=5,1,52,701"
            standby="Loading Microsoft® Windows® Media Player components..." type="application/x-oleobject"
            >
            <param name="FileName" value='<%= GetSource() %>' />
            <param name="AutoStart" value="True" />
            <param name="DefaultFrame" value="mainFrame" />
            <param name="ShowStatusBar" value="0" />
            <param name="ShowPositionControls" value="0" />
            <param name="showcontrols" value="0" />
            <param name="ShowAudioControls" value="0" />
            <param name="ShowTracker" value="0" />
            <param name="EnablePositionControls" value="0" />


            <!-- BEGIN PLUG-IN HTML FOR FIREFOX-->
            <embed  type="application/x-mplayer2" pluginspage="http://www.microsoft.com/Windows/MediaPlayer/"
                src='<%= GetSource() %>' align="middle" width="600" height="500" defaultframe="rightFrame"
                 id="MediaPlayer2" />

And in JavaScript,

    function playVideo() {
        try{
                if(-1 != navigator.userAgent.indexOf("MSIE"))
                {
                        var obj = document.getElementById("MediaPlayer1");
                            obj.Play();

                }
                else
                {
                            var player = document.getElementById("MediaPlayer2");
                            player.controls.play();

                }
             }  
        catch(error) {
            alert(error)
        } 


        }

How to get default gateway in Mac OSX

The grep utility is not needed. Awk can do it all:

    netstat -rn | awk '/default/ {print $2}'
      192.168.128.1

Note that if you have something like Parallels (or a VPN, or both) running, you may see two or more default routing entries - it will be true if you use the 'grep' suggestion above, too.

    netstat -rn | awk '/default/ {print $2}'
      192.168.128.1
      link#12

and

    netstat -rn | awk '/default/ {print $2}'                             
      utun1
      192.168.128.1
      link#12

To set a variable (_default) for further use (assuming only one entry for 'default') .....

    _default=$( netstat -rn inet | awk '/default/ {print $2}' ) # I prefer $( ... ) over back-ticks

In the case of multiple default routes use:

    netstat -rn | awk '/default/ {if ( index($6, "en") > 0 ){print $2} }'
      192.168.128.1

These examples tested in Mavericks Terminal.app and are specific to OSX only. For example, other *nix versions frequently use 'eth' for ethernet/wireless connections, not 'en'. This is also only tested with ksh. Other shells may need a slightly different syntax.

How do I create a branch?

Create a new branch using the svn copy command as follows:

$ svn copy svn+ssh://host.example.com/repos/project/trunk \
           svn+ssh://host.example.com/repos/project/branches/NAME_OF_BRANCH \
      -m "Creating a branch of project"

How to find out what is locking my tables?

exec sp_lock

This query should give you existing locks.

exec sp_who SPID -- will give you some info

Having spids, you could check activity monitor(processes tab) to find out what processes are locking the tables ("details" for more info and "kill process" to kill it).

Remove characters except digits from string using Python?

The op mentions in the comments that he wants to keep the decimal place. This can be done with the re.sub method (as per the second and IMHO best answer) by explicitly listing the characters to keep e.g.

>>> re.sub("[^0123456789\.]","","poo123.4and5fish")
'123.45'

Average of multiple columns

Select Req_ID, sum(R1+R2+R3+R4+R5)/5 as Average
from Request
Group by Req_ID;

What's the difference between "Request Payload" vs "Form Data" as seen in Chrome dev tools Network tab

The Request Payload - or to be more precise: payload body of a HTTP Request - is the data normally send by a POST or PUT Request. It's the part after the headers and the CRLF of a HTTP Request.

A request with Content-Type: application/json may look like this:

POST /some-path HTTP/1.1
Content-Type: application/json

{ "foo" : "bar", "name" : "John" }

If you submit this per AJAX the browser simply shows you what it is submitting as payload body. That’s all it can do because it has no idea where the data is coming from.

If you submit a HTML-Form with method="POST" and Content-Type: application/x-www-form-urlencoded or Content-Type: multipart/form-data your request may look like this:

POST /some-path HTTP/1.1
Content-Type: application/x-www-form-urlencoded

foo=bar&name=John

In this case the form-data is the request payload. Here the Browser knows more: it knows that bar is the value of the input-field foo of the submitted form. And that’s what it is showing to you.

So, they differ in the Content-Type but not in the way data is submitted. In both cases the data is in the message-body. And Chrome distinguishes how the data is presented to you in the Developer Tools.

how to "execute" make file

As paxdiablo said make -f pax.mk would execute the pax.mk makefile, if you directly execute it by typing ./pax.mk, then you would get syntax error.

Also you can just type make if your file name is makefile/Makefile.

Suppose you have two files named makefile and Makefile in the same directory then makefile is executed if make alone is given. You can even pass arguments to makefile.

Check out more about makefile at this Tutorial : Basic understanding of Makefile

jQuery Validate Required Select

I don't know how was the plugin the time the question was asked (2010), but I faced the same problem today and solved it this way:

  1. Give your select tag a name attribute. For example in this case

    <select name="myselect">

  2. Instead of working with the attribute value="default" in the tag option, disable the default option or set value="" as suggested by Andrew Coats

    <option disabled="disabled">Choose...</option>

    or

    <option value="">Choose...</option>

  3. Set the plugin validation rule

    $( "#YOUR_FORM_ID" ).validate({ rules: { myselect: { required: true } } });

    or

    <select name="myselect" class="required">

Obs: Andrew Coats' solution works only if you have just one select in your form. If you want his solution to work with more than one select add a name attribute to your select.

Hope it helps! :)

Return background color of selected cell

If you are looking at a Table, a Pivot Table, or something with conditional formatting, you can try:

ActiveCell.DisplayFormat.Interior.Color

This also seems to work just fine on regular cells.

How to define a List bean in Spring?

And this is how to inject set in some property in Spring:

<bean id="process"
      class="biz.bsoft.processing">
    <property name="stages">
        <set value-type="biz.bsoft.AbstractStage">
            <ref bean="stageReady"/>
            <ref bean="stageSteady"/>
            <ref bean="stageGo"/>
        </set>
    </property>
</bean>

Where does Android app package gets installed on phone

The package it-self is located under /data/app/com.company.appname-xxx.apk.

/data/app/com.company.appname is only a directory created to store files like native libs, cache, ecc...

You can retrieve the package installation path with the Context.getPackageCodePath() function call.

Why is using onClick() in HTML a bad practice?

You're probably talking about unobtrusive Javascript, which would look like this:

<a href="#" id="someLink">link</a>

with the logic in a central javascript file looking something like this:

$('#someLink').click(function(){
    popup('/map/', 300, 300, 'map'); 
    return false;
});

The advantages are

  • behaviour (Javascript) is separated from presentation (HTML)
  • no mixing of languages
  • you're using a javascript framework like jQuery that can handle most cross-browser issues for you
  • You can add behaviour to a lot of HTML elements at once without code duplication

How can I delete (not disable) ActiveX add-ons in Internet Explorer (7 and 8 Beta 2)?

Tools > Manage Add-ons, right click "Name" header and enable the "In Folder" section. go to the directory for the plugin you're interested in. Right click the plugin file, and click "remove".

How to set HTML Auto Indent format on Sublime Text 3?

Create a Keybinding

To auto indent on Sublime text 3 with a key bind try going to

Preferences > Key Bindings - users

And adding this code between the square brackets

{"keys": ["alt+shift+f"], "command": "reindent", "args": {"single_line": false}}

it sets shift + alt + f to be your full page auto indent.

Source here

Note: if this doesn't work correctly then you should convert your indentation to tabs. Also comments in your code can push your code to the wrong indentation level and may have to be moved manually.

How to grep (search) committed code in the Git history

Okay, twice just today I've seen people wanting a closer equivalent for hg grep, which is like git log -pS but confines its output to just the (annotated) changed lines.

Which I suppose would be handier than /pattern/ in the pager if you're after a quick overview.

So here's a diff-hunk scanner that takes git log --pretty=%h -p output and spits annotated change lines. Put it in diffmarkup.l, say e.g. make ~/bin/diffmarkup, and use it like

git log --pretty=%h -pS pattern | diffmarkup | grep pattern
%option main 8bit nodefault
        // vim: tw=0
%top{
        #define _GNU_SOURCE 1
}
%x commitheader
%x diffheader
%x hunk
%%
        char *afile=0, *bfile=0, *commit=0;
        int aline,aremain,bline,bremain;
        int iline=1;

<hunk>\n        ++iline; if ((aremain+bremain)==0) BEGIN diffheader;
<*>\n   ++iline;

<INITIAL,commitheader,diffheader>^diff.*        BEGIN diffheader;
<INITIAL>.*     BEGIN commitheader; if(commit)free(commit); commit=strdup(yytext);
<commitheader>.*

<diffheader>^(deleted|new|index)" ".*   {}
<diffheader>^"---".*            if (afile)free(afile); afile=strdup(strchrnul(yytext,'/'));
<diffheader>^"+++".*            if (bfile)free(bfile); bfile=strdup(strchrnul(yytext,'/'));
<diffheader,hunk>^"@@ ".*       {
        BEGIN hunk; char *next=yytext+3;
        #define checkread(format,number) { int span; if ( !sscanf(next,format"%n",&number,&span) ) goto lostinhunkheader; next+=span; }
        checkread(" -%d",aline); if ( *next == ',' ) checkread(",%d",aremain) else aremain=1;
        checkread(" +%d",bline); if ( *next == ',' ) checkread(",%d",bremain) else bremain=1;
        break;
        lostinhunkheader: fprintf(stderr,"Lost at line %d, can't parse hunk header '%s'.\n",iline,yytext), exit(1);
        }
<diffheader>. yyless(0); BEGIN INITIAL;

<hunk>^"+".*    printf("%s:%s:%d:%c:%s\n",commit,bfile+1,bline++,*yytext,yytext+1); --bremain;
<hunk>^"-".*    printf("%s:%s:%d:%c:%s\n",commit,afile+1,aline++,*yytext,yytext+1); --aremain;
<hunk>^" ".*    ++aline, ++bline; --aremain; --bremain;
<hunk>. fprintf(stderr,"Lost at line %d, Can't parse hunk.\n",iline), exit(1);

Single Page Application: advantages and disadvantages

I understand this is an older question, but I would like to add another disadvantage of Single Page Applications:

If you build an API that returns results in a data language (such as XML or JSON) rather than a formatting language (like HTML), you are enabling greater application interoperability, for example, in business-to-business (B2B) applications. Such interoperability has great benefits but does allow people to write software to "mine" (or steal) your data. This particular disadvantage is common to all APIs that use a data language, and not to SPAs in general (indeed, an SPA that asks the server for pre-rendered HTML avoids this, but at the expense of poor model/view separation). This risk exposed by this disadvantage can be mitigated by various means, such as request limiting and connection blocking, etc.

how to send an array in url request

Separate with commas:

http://localhost:8080/MovieDB/GetJson?name=Actor1,Actor2,Actor3&startDate=20120101&endDate=20120505

or:

http://localhost:8080/MovieDB/GetJson?name=Actor1&name=Actor2&name=Actor3&startDate=20120101&endDate=20120505

or:

http://localhost:8080/MovieDB/GetJson?name[0]=Actor1&name[1]=Actor2&name[2]=Actor3&startDate=20120101&endDate=20120505

Either way, your method signature needs to be:

@RequestMapping(value = "/GetJson", method = RequestMethod.GET) 
public void getJson(@RequestParam("name") String[] ticker, @RequestParam("startDate") String startDate, @RequestParam("endDate") String endDate) {
   //code to get results from db for those params.
 }

Scale image to fit a bounding box

.boundingbox {
    width: 400px;
    height: 500px;
    border: 2px solid #F63;
}
img{
    width:400px;
    max-height: 500px;
    height:auto;
}

I'm editing my answer to further explain my soluton as I've got a down vote.

With the styles set as shown above in css, now the following html div will show the image always fit width wise and will adjust hight aspect ratio to width. Thus image will scale to fit a bounding box as asked in the question.

<div class="boundingbox"><img src="image.jpg"/></div>

target="_blank" vs. target="_new"

  • _blank as a target value will spawn a new window every time,
  • _new will only spawn one new window.

Also, every link clicked with a target value of _new will replace the page loaded in the previously spawned window.

You can click here When to use _blank or _new to try it out for yourself.

Avoid printStackTrace(); use a logger call instead

A production quality program should use one of the many logging alternatives (e.g. log4j, logback, java.util.logging) to report errors and other diagnostics. This has a number of advantages:

  • Log messages go to a configurable location.
  • The end user doesn't see the messages unless you configure the logging so that he/she does.
  • You can use different loggers and logging levels, etc to control how much little or much logging is recorded.
  • You can use different appender formats to control what the logging looks like.
  • You can easily plug the logging output into a larger monitoring / logging framework.
  • All of the above can be done without changing your code; i.e. by editing the deployed application's logging config file.

By contrast, if you just use printStackTrace, the deployer / end user has little if any control, and logging messages are liable to either be lost or shown to the end user in inappropriate circumstances. (And nothing terrifies a timid user more than a random stack trace.)

Hot deploy on JBoss - how do I make JBoss "see" the change?

Deploy the app as exploded (project.war folder), add in your web.xml:

<web-app>
    <context-param>
        <param-name>org.jboss.weld.development</param-name>
        <param-value>true</param-value>
    </context-param>

Update the web.xml time every-time you deploy (append blank line):

set PRJ_HOME=C:\Temp2\MyProject\src\main\webapp
set PRJ_CLSS_HOME=%PRJ_HOME%\WEB-INF\classes\com\myProject

set JBOSS_HOME= C:\Java\jboss-4.2.3.GA-jdk6\server\default\deploy\MyProject.war
set JBOSS_CLSS_HOME= %JBOSS_HOME%\WEB-INF\classes\com\myProject

copy %PRJ_CLSS_HOME%\frontend\actions\profile\ProfileAction.class %JBOSS_CLSS_HOME%\frontend\actions\profile\ProfileAction.class
copy %PRJ_CLSS_HOME%\frontend\actions\profile\AjaxAction.class %JBOSS_CLSS_HOME%\frontend\actions\profile\AjaxAction.class

ECHO.>>%JBOSS_HOME%\WEB-INF\web.xml

Python 2.7.10 error "from urllib.request import urlopen" no module named request

For now, it seems that I could get over that by adding a ? after the URL.

Ideal way to cancel an executing AsyncTask

This is how I write my AsyncTask
the key point is add Thread.sleep(1);

@Override   protected Integer doInBackground(String... params) {

        Log.d(TAG, PRE + "url:" + params[0]);
        Log.d(TAG, PRE + "file name:" + params[1]);
        downloadPath = params[1];

        int returnCode = SUCCESS;
        FileOutputStream fos = null;
        try {
            URL url = new URL(params[0]);
            File file = new File(params[1]);
            fos = new FileOutputStream(file);

            long startTime = System.currentTimeMillis();
            URLConnection ucon = url.openConnection();
            InputStream is = ucon.getInputStream();
            BufferedInputStream bis = new BufferedInputStream(is);

            byte[] data = new byte[10240]; 
            int nFinishSize = 0;
            while( bis.read(data, 0, 10240) != -1){
                fos.write(data, 0, 10240);
                nFinishSize += 10240;
                **Thread.sleep( 1 ); // this make cancel method work**
                this.publishProgress(nFinishSize);
            }              
            data = null;    
            Log.d(TAG, "download ready in"
                  + ((System.currentTimeMillis() - startTime) / 1000)
                  + " sec");

        } catch (IOException e) {
                Log.d(TAG, PRE + "Error: " + e);
                returnCode = FAIL;
        } catch (Exception e){
                 e.printStackTrace();           
        } finally{
            try {
                if(fos != null)
                    fos.close();
            } catch (IOException e) {
                Log.d(TAG, PRE + "Error: " + e);
                e.printStackTrace();
            }
        }

        return returnCode;
    }

Why does JPA have a @Transient annotation?

I will try to answer the question of "why". Imagine a situation where you have a huge database with a lot of columns in a table, and your project/system uses tools to generate entities from database. (Hibernate has those, etc...) Now, suppose that by your business logic you need a particular field NOT to be persisted. You have to "configure" your entity in a particular way. While Transient keyword works on an object - as it behaves within a java language, the @Transient only designed to answer the tasks that pertains only to persistence tasks.

The superclass "javax.servlet.http.HttpServlet" was not found on the Java Build Path

In case of JBoss... right click on project ? Build Java path ? add external JAR files.

Then browse to jboss-folder ? Common ? lib ? servlet-api.jar

. . Click OK, refresh the project, and run it...

jQuery Change event on an <input> element - any way to retain previous value?

A better approach is to store the old value using .data. This spares the creation of a global var which you should stay away from and keeps the information encapsulated within the element. A real world example as to why Global Vars are bad is documented here

e.g

<script>
    //look no global needed:)

    $(document).ready(function(){
        // Get the initial value
       var $el = $('#myInputElement');
       $el.data('oldVal',  $el.val() );


       $el.change(function(){
            //store new value
            var $this = $(this);
            var newValue = $this.data('newVal', $this.val());
       })
       .focus(function(){
            // Get the value when input gains focus
            var oldValue = $(this).data('oldVal');
       });
    });
</script>
<input id="myInputElement" type="text">

How to get Domain name from URL using jquery..?

Try like this.

var hostname = window.location.origin

If the URL is "http://example.com/path" then you will get  "http://example.com" as the result.

This won't work for local domains

When you have URL like "https://localhost/MyProposal/MyDir/MyTestPage.aspx" 
and your virtual directory path is "https://localhost/MyProposal/" 
In such cases, you will get "https://localhost".

C++ JSON Serialization

The jsoncons C++ header-only library also supports conversion between JSON text and C++ objects. Decode and encode are defined for all C++ classes that have json_type_traits defined. The standard library containers are already supported, and json_type_traits can be specialized for user types in the jsoncons namespace.

Below is an example:

#include <iostream>
#include <jsoncons/json.hpp>

namespace ns {
    enum class hiking_experience {beginner,intermediate,advanced};

    class hiking_reputon
    {
        std::string rater_;
        hiking_experience assertion_;
        std::string rated_;
        double rating_;
    public:
        hiking_reputon(const std::string& rater,
                       hiking_experience assertion,
                       const std::string& rated,
                       double rating)
            : rater_(rater), assertion_(assertion), rated_(rated), rating_(rating)
        {
        }

        const std::string& rater() const {return rater_;}
        hiking_experience assertion() const {return assertion_;}
        const std::string& rated() const {return rated_;}
        double rating() const {return rating_;}
    };

    class hiking_reputation
    {
        std::string application_;
        std::vector<hiking_reputon> reputons_;
    public:
        hiking_reputation(const std::string& application, 
                          const std::vector<hiking_reputon>& reputons)
            : application_(application), 
              reputons_(reputons)
        {}

        const std::string& application() const { return application_;}
        const std::vector<hiking_reputon>& reputons() const { return reputons_;}
    };

} // namespace ns

// Declare the traits using convenience macros. Specify which data members need to be serialized.

JSONCONS_ENUM_TRAITS_DECL(ns::hiking_experience, beginner, intermediate, advanced)
JSONCONS_ALL_CTOR_GETTER_TRAITS(ns::hiking_reputon, rater, assertion, rated, rating)
JSONCONS_ALL_CTOR_GETTER_TRAITS(ns::hiking_reputation, application, reputons)

using namespace jsoncons; // for convenience

int main()
{

std::string data = R"(
    {
       "application": "hiking",
       "reputons": [
       {
           "rater": "HikingAsylum",
           "assertion": "advanced",
           "rated": "Marilyn C",
           "rating": 0.90
         }
       ]
    }
)";

    // Decode the string of data into a c++ structure
    ns::hiking_reputation v = decode_json<ns::hiking_reputation>(data);

    // Iterate over reputons array value
    std::cout << "(1)\n";
    for (const auto& item : v.reputons())
    {
        std::cout << item.rated() << ", " << item.rating() << "\n";
    }

    // Encode the c++ structure into a string
    std::string s;
    encode_json<ns::hiking_reputation>(v, s, indenting::indent);
    std::cout << "(2)\n";
    std::cout << s << "\n";
}    

Output:

(1)
Marilyn C, 0.9
(2)
{
    "application": "hiking",
    "reputons": [
        {
            "assertion": "advanced",
            "rated": "Marilyn C",
            "rater": "HikingAsylum",
            "rating": 0.9
        }
    ]
}

Python: pandas merge multiple dataframes

There are 2 solutions for this, but it return all columns separately:

import functools

dfs = [df1, df2, df3]

df_final = functools.reduce(lambda left,right: pd.merge(left,right,on='date'), dfs)
print (df_final)
          date     a_x   b_x       a_y      b_y   c_x         a        b   c_y
0  May 15,2017  900.00  0.2%  1,900.00  1000000  0.2%  2,900.00  2000000  0.2%

k = np.arange(len(dfs)).astype(str)
df = pd.concat([x.set_index('date') for x in dfs], axis=1, join='inner', keys=k)
df.columns = df.columns.map('_'.join)
print (df)
                0_a   0_b       1_a      1_b   1_c       2_a      2_b   2_c
date                                                                       
May 15,2017  900.00  0.2%  1,900.00  1000000  0.2%  2,900.00  2000000  0.2%

Getting all types that implement an interface

To find all types in an assembly that implement IFoo interface:

var results = from type in someAssembly.GetTypes()
              where typeof(IFoo).IsAssignableFrom(type)
              select type;

Note that Ryan Rinaldi's suggestion was incorrect. It will return 0 types. You cannot write

where type is IFoo

because type is a System.Type instance, and will never be of type IFoo. Instead, you check to see if IFoo is assignable from the type. That will get your expected results.

Also, Adam Wright's suggestion, which is currently marked as the answer, is incorrect as well, and for the same reason. At runtime, you'll see 0 types come back, because all System.Type instances weren't IFoo implementors.

How can I detect keydown or keypress event in angular.js?

You can checkout Angular UI @ http://angular-ui.github.io/ui-utils/ which provide details event handle callback function for detecting keydown,keyup,keypress (also Enter key, backspace key, alter key ,control key)

<textarea ui-keydown="{27:'keydownCallback($event)'}"></textarea>
<textarea ui-keypress="{13:'keypressCallback($event)'}"></textarea>
<textarea ui-keydown="{'enter alt-space':'keypressCallback($event)'}"> </textarea>
<textarea ui-keyup="{'enter':'keypressCallback($event)'}"> </textarea>

Centering a canvas

Wrapping it with div should work. I tested it in Firefox, Chrome on Fedora 13 (demo).

#content {
   width: 95%;
   height: 95%;
   margin: auto;
}

#myCanvas {
   width: 100%;
   height: 100%;
   border: 1px solid black;
}

And the canvas should be enclosed in tag

<div id="content">
    <canvas id="myCanvas">Your browser doesn't support canvas tag</canvas>
</div>

Let me know if it works. Cheers.

How to generate List<String> from SQL query?

Or a nested List (okay, the OP was for a single column and this is for multiple columns..):

        //Base list is a list of fields, ie a data record
        //Enclosing list is then a list of those records, ie the Result set
        List<List<String>> ResultSet = new List<List<String>>();

        using (SqlConnection connection =
            new SqlConnection(connectionString))
        {
            // Create the Command and Parameter objects.
            SqlCommand command = new SqlCommand(qString, connection);

            // Create and execute the DataReader..
            connection.Open();
            SqlDataReader reader = command.ExecuteReader();
            while (reader.Read())
            {
                var rec = new List<string>();
                for (int i = 0; i <= reader.FieldCount-1; i++) //The mathematical formula for reading the next fields must be <=
                {                      
                    rec.Add(reader.GetString(i));
                }
                ResultSet.Add(rec);

            }
        }