Programs & Examples On #Searchbar

React - clearing an input value after form submit

this.mainInput doesn't actually point to anything. Since you are using a controlled component (i.e. the value of the input is obtained from state) you can set this.state.city to null:

onHandleSubmit(e) {
  e.preventDefault();
  const city = this.state.city;
  this.props.onSearchTermChange(city);
  this.setState({ city: '' });
}

Set UITableView content inset permanently

automaticallyAdjustsScrollViewInsets is deprecated in iOS11 (and the accepted solution no longer works). use:

if #available(iOS 11.0, *) {
    scrollView.contentInsetAdjustmentBehavior = .never
} else {
    automaticallyAdjustsScrollViewInsets = false
}

CSS fill remaining width

I know its quite late to answer this, but I guess it will help anyone ahead.

Well using CSS3 FlexBox. It can be acheived. Make you header as display:flex and divide its entire width into 3 parts. In the first part I have placed the logo, the searchbar in second part and buttons container in last part. apply justify-content: between to the header container and flex-grow:1 to the searchbar. That's it. The sample code is below.

_x000D_
_x000D_
#header {_x000D_
  background-color: #323C3E;_x000D_
  justify-content: space-between;_x000D_
  display: flex;_x000D_
}_x000D_
_x000D_
#searchBar, img{_x000D_
  align-self: center;_x000D_
}_x000D_
_x000D_
#searchBar{_x000D_
  flex-grow:1;_x000D_
  background-color: orange;_x000D_
  padding: 10px;_x000D_
}_x000D_
_x000D_
#searchBar input {_x000D_
  width: 100%;_x000D_
}_x000D_
_x000D_
.button {_x000D_
  padding: 22px;_x000D_
}_x000D_
_x000D_
.buttonsHolder{_x000D_
  display:flex;_x000D_
}
_x000D_
<div id="header" class="d-flex justify-content-between">_x000D_
    <img src="img/logo.png" />_x000D_
    <div id="searchBar">_x000D_
      <input type="text" />_x000D_
    </div>_x000D_
    <div class="buttonsHolder">_x000D_
      <div class="button orange inline" id="myAccount">_x000D_
        My Account_x000D_
      </div>_x000D_
      <div class="button red inline" id="basket">_x000D_
        Basket (2)_x000D_
      </div>_x000D_
    </div>_x000D_
</div>
_x000D_
_x000D_
_x000D_

Set value of textbox using JQuery

$(document).ready(function() {
 $('#main_search').val('hi');
});

Pagination on a list using ng-repeat

I know this thread is old now but I am answering it to keep things a bit updated.

With Angular 1.4 and above you can directly use limitTo filter which apart from accepting the limit parameter also accepts a begin parameter.

Usage: {{ limitTo_expression | limitTo : limit : begin}}

So now you may not need to use any third party library to achieve something like pagination. I have created a fiddle to illustrate the same.

Remove all whitespaces from NSString

This may help you if you are experiencing \u00a0 in stead of (whitespace). I had this problem when I was trying to extract Device Contact Phone Numbers. I needed to modify the phoneNumber string so it has no whitespace in it.

NSString* yourString = [yourString stringByReplacingOccurrencesOfString:@"\u00a0" withString:@""];

When yourString was the current phone number.

HTML5 placeholder css padding

line-height: normal; 

worked for me ;)

Changing Tint / Background color of UITabBar

[v setBackgroundColor ColorwithRed: Green: Blue: ];

How do I change a tab background color when using TabLayout?

What finally worked for me is similar to what @????DJ suggested, but the tabBackground should be in the layout file and not inside the style, so it looks like:

res/layout/somefile.xml:

<android.support.design.widget.TabLayout
    ....
    app:tabBackground="@drawable/tab_color_selector"
    ...
    />

and the selector res/drawable/tab_color_selector.xml:

<?xml version="1.0" encoding="utf-8"?>
<selector xmlns:android="http://schemas.android.com/apk/res/android">
    <item android:drawable="@color/tab_background_selected" android:state_selected="true"/>
    <item android:drawable="@color/tab_background_unselected"/>
</selector>

Can I do a max(count(*)) in SQL?

     select top 1 yr,count(*)  from movie
join casting on casting.movieid=movie.id
join actor on casting.actorid = actor.id
where actor.name = 'John Travolta'
group by yr order by 2 desc

Android: Expand/collapse animation

Here are two simple kotlin extension functions over view.

fun View.expand() {
    visibility = View.VISIBLE
    val animate = TranslateAnimation(0f, 0f, -height.toFloat(), 0f)
    animate.duration = 200
    animate.fillAfter = true
    startAnimation(animate)
}

fun View.collapse() {
    val animate = TranslateAnimation(0f, 0f, 0f, -height.toFloat() )
    animate.duration = 200
    animate.fillAfter = true
    startAnimation(animate)
}

What is the best way to concatenate two vectors?

All the solutions are correct, but I found it easier just write a function to implement this. like this:

template <class T1, class T2>
void ContainerInsert(T1 t1, T2 t2)
{
    t1->insert(t1->end(), t2->begin(), t2->end());
}

That way you can avoid the temporary placement like this:

ContainerInsert(vec, GetSomeVector());

Regex for parsing directory and filename

In languages that support regular expressions with non-capturing groups:

((?:[^/]*/)*)(.*)

I'll explain the gnarly regex by exploding it...

(
  (?:
    [^/]*
    /
  )
  *
)
(.*)

What the parts mean:

(  -- capture group 1 starts
  (?:  -- non-capturing group starts
    [^/]*  -- greedily match as many non-directory separators as possible
    /  -- match a single directory-separator character
  )  -- non-capturing group ends
  *  -- repeat the non-capturing group zero-or-more times
)  -- capture group 1 ends
(.*)  -- capture all remaining characters in group 2

Example

To test the regular expression, I used the following Perl script...

#!/usr/bin/perl -w

use strict;
use warnings;

sub test {
  my $str = shift;
  my $testname = shift;

  $str =~ m#((?:[^/]*/)*)(.*)#;

  print "$str -- $testname\n";
  print "  1: $1\n";
  print "  2: $2\n\n";
}

test('/var/log/xyz/10032008.log', 'absolute path');
test('var/log/xyz/10032008.log', 'relative path');
test('10032008.log', 'filename-only');
test('/10032008.log', 'file directly under root');

The output of the script...

/var/log/xyz/10032008.log -- absolute path
  1: /var/log/xyz/
  2: 10032008.log

var/log/xyz/10032008.log -- relative path
  1: var/log/xyz/
  2: 10032008.log

10032008.log -- filename-only
  1:
  2: 10032008.log

/10032008.log -- file directly under root
  1: /
  2: 10032008.log

How to create a new schema/new user in Oracle Database 11g?

SQL> select Username from dba_users
  2  ;

USERNAME
------------------------------
SYS
SYSTEM
ANONYMOUS
APEX_PUBLIC_USER
FLOWS_FILES
APEX_040000
OUTLN
DIP
ORACLE_OCM
XS$NULL
MDSYS

USERNAME
------------------------------
CTXSYS
DBSNMP
XDB
APPQOSSYS
HR

16 rows selected.

SQL> create user testdb identified by password;

User created.

SQL> select username from dba_users;

USERNAME
------------------------------
TESTDB
SYS
SYSTEM
ANONYMOUS
APEX_PUBLIC_USER
FLOWS_FILES
APEX_040000
OUTLN
DIP
ORACLE_OCM
XS$NULL

USERNAME
------------------------------
MDSYS
CTXSYS
DBSNMP
XDB
APPQOSSYS
HR

17 rows selected.

SQL> grant create session to testdb;

Grant succeeded.

SQL> create tablespace testdb_tablespace
  2  datafile 'testdb_tabspace.dat'
  3  size 10M autoextend on;

Tablespace created.

SQL> create temporary tablespace testdb_tablespace_temp
  2  tempfile 'testdb_tabspace_temp.dat'
  3  size 5M autoextend on;

Tablespace created.

SQL> drop user testdb;

User dropped.

SQL> create user testdb
  2  identified by password
  3  default tablespace testdb_tablespace
  4  temporary tablespace testdb_tablespace_temp;

User created.

SQL> grant create session to testdb;

Grant succeeded.

SQL> grant create table to testdb;

Grant succeeded.

SQL> grant unlimited tablespace to testdb;

Grant succeeded.

SQL>

Read file As String

public static String readFileToString(String filePath) {
    InputStream in = Test.class.getResourceAsStream(filePath);//filePath="/com/myproject/Sample.xml"
    try {
        return IOUtils.toString(in, StandardCharsets.UTF_8);
    } catch (IOException e) {
        logger.error("Failed to read the xml : ", e);
    }
    return null;
}

MySQL Select Date Equal to Today

SELECT users.id, DATE_FORMAT(users.signup_date, '%Y-%m-%d') 
FROM users 
WHERE DATE(signup_date) = CURDATE()

Spring 5.0.3 RequestRejectedException: The request was rejected because the URL was not normalized

In my case, the problem was caused by not being logged in with Postman, so I opened a connection in another tab with a session cookie I took from the headers in my Chrome session.

How can I remove Nan from list Python/NumPy

The question has changed, so to has the answer:

Strings can't be tested using math.isnan as this expects a float argument. In your countries list, you have floats and strings.

In your case the following should suffice:

cleanedList = [x for x in countries if str(x) != 'nan']

Old answer

In your countries list, the literal 'nan' is a string not the Python float nan which is equivalent to:

float('NaN')

In your case the following should suffice:

cleanedList = [x for x in countries if x != 'nan']

React Checkbox not sending onChange

onChange will not call handleChange on mobile when using defaultChecked. As an alternative you can can use onClick and onTouchEnd.

<input onClick={this.handleChange} onTouchEnd={this.handleChange} type="checkbox" defaultChecked={!!this.state.complete} />;

Possible to view PHP code of a website?

Noone cand read the file except for those who have access to the file. You must make the code readable (but not writable) by the web server. If the php code handler is running properly you can't read it by requesting by name from the web server.

If someone compromises your server you are at risk. Ensure that the web server can only write to locations it absolutely needs to. There are a few locations under /var which should be properly configured by your distribution. They should not be accessible over the web. /var/www should not be writable, but may contain subdirectories written to by the web server for dynamic content. Code handlers should be disabled for these.

Ensure you don't do anything in your php code which can lead to code injection. The other risk is directory traversal using paths containing .. or begining with /. Apache should already be patched to prevent this when it is handling paths. However, when it runs code, including php, it does not control the paths. Avoid anything that allows the web client to pass a file path.

Printing image with PrintDocument. how to adjust the image to fit paper size

You can use my code here

//Print Button Event Handeler
private void btnPrint_Click(object sender, EventArgs e)
{
    PrintDocument pd = new PrintDocument();
    pd.PrintPage += PrintPage;
    //here to select the printer attached to user PC
    PrintDialog printDialog1 = new PrintDialog();
    printDialog1.Document = pd;
    DialogResult result = printDialog1.ShowDialog();
    if (result == DialogResult.OK)
    {
        pd.Print();//this will trigger the Print Event handeler PrintPage
    }
}

//The Print Event handeler
private void PrintPage(object o, PrintPageEventArgs e)
{
    try
    {
        if (File.Exists(this.ImagePath))
        {
            //Load the image from the file
            System.Drawing.Image img = System.Drawing.Image.FromFile(@"C:\myimage.jpg");

            //Adjust the size of the image to the page to print the full image without loosing any part of it
            Rectangle m = e.MarginBounds;

            if ((double)img.Width / (double)img.Height > (double)m.Width / (double)m.Height) // image is wider
            {
                m.Height = (int)((double)img.Height / (double)img.Width * (double)m.Width);
            }
            else
            {
                m.Width = (int)((double)img.Width / (double)img.Height * (double)m.Height);
            }
            e.Graphics.DrawImage(img, m);
        }
    }
    catch (Exception)
    {

    }
}

How to find char in string and get all the indexes?

This is slightly modified version of Mark Ransom's answer that works if ch could be more than one character in length.

def find(term, ch):
    """Find all places with ch in str
    """
    for i in range(len(term)):
        if term[i:i + len(ch)] == ch:
            yield i

Could not load file or assembly 'System.Web.WebPages.Razor, Version=2.0.0.0

I downgraded via NuGet to MVC 4 and then upgraded again to 5.2.7 and it fixed this issue

Allow only numbers and dot in script

Hope this could help someone

$(document).on("input", ".numeric", function() {
this.value = this.value.match(/^\d+\.?\d{0,2}/);});

Custom events in jQuery?

I had a similar question, but was actually looking for a different answer; I'm looking to create a custom event. For example instead of always saying this:

$('#myInput').keydown(function(ev) {
    if (ev.which == 13) {
        ev.preventDefault();
        // Do some stuff that handles the enter key
    }
});

I want to abbreviate it to this:

$('#myInput').enterKey(function() {
    // Do some stuff that handles the enter key
});

trigger and bind don't tell the whole story - this is a JQuery plugin. http://docs.jquery.com/Plugins/Authoring

The "enterKey" function gets attached as a property to jQuery.fn - this is the code required:

(function($){
    $('body').on('keydown', 'input', function(ev) {
        if (ev.which == 13) {
            var enterEv = $.extend({}, ev, { type: 'enterKey' });
            return $(ev.target).trigger(enterEv);
        }
    });

    $.fn.enterKey = function(selector, data, fn) {
        return this.on('enterKey', selector, data, fn);
    };
})(jQuery);

http://jsfiddle.net/b9chris/CkvuJ/4/

A nicety of the above is you can handle keyboard input gracefully on link listeners like:

$('a.button').on('click enterKey', function(ev) {
    ev.preventDefault();
    ...
});

Edits: Updated to properly pass the right this context to the handler, and to return any return value back from the handler to jQuery (for example in case you were looking to cancel the event and bubbling). Updated to pass a proper jQuery event object to handlers, including key code and ability to cancel event.

Old jsfiddle: http://jsfiddle.net/b9chris/VwEb9/24/

Write bytes to file

The simplest way would be to convert your hexadecimal string to a byte array and use the File.WriteAllBytes method.

Using the StringToByteArray() method from this question, you'd do something like this:

string hexString = "0CFE9E69271557822FE715A8B3E564BE";

File.WriteAllBytes("output.dat", StringToByteArray(hexString));

The StringToByteArray method is included below:

public static byte[] StringToByteArray(string hex) {
    return Enumerable.Range(0, hex.Length)
                     .Where(x => x % 2 == 0)
                     .Select(x => Convert.ToByte(hex.Substring(x, 2), 16))
                     .ToArray();
}

<button> vs. <input type="button" />. Which to use?

<button>
  • by default behaves like if it had a "type="submit" attribute
  • can be used without a form as well as in forms.
  • text or html content allowed
  • css pseudo elements allowed (like :before)
  • tag name is usually unique to a single form

vs.

<input type='button'>
  • type should be set to 'submit' to behave as a submitting element
  • can only be used in forms.
  • only text content allowed
  • no css pseudo elements
  • same tag name as most of the forms elements (inputs)

--
in modern browsers, both elements are easily styleable with css but in most cases, button element is preferred as you can style more with inner html and pseudo elements

Java method to sum any number of ints

If your using Java8 you can use the IntStream:

int[] listOfNumbers = {5,4,13,7,7,8,9,10,5,92,11,3,4,2,1};
System.out.println(IntStream.of(listOfNumbers).sum());

Results: 181

Just 1 line of code which will sum the array.

How can I see CakePHP's SQL dump in the controller?

for cakephp 2.0 Write this function in AppModel.php

function getLastQuery()
{
    $dbo = $this->getDatasource();
    $logs = $dbo->getLog();
    $lastLog = end($logs['log']);
    return $lastLog['query'];
}

To use this in Controller Write : echo $this->YourModelName->getLastQuery();

Spring data jpa- No bean named 'entityManagerFactory' is defined; Injection of autowired dependencies failed

I had this issue after migrating from spring-boot-starter-data-jpa ver. 1.5.7 to 2.0.2 (from old hibernate to hibernate 5.2). In my @Configuration class I injected entityManagerFactory and transactionManager.

//I've got my data source defined in application.yml config file, 
//so there is no need to configure it from java.
@Autowired
DataSource dataSource;

@Bean
public LocalContainerEntityManagerFactoryBean entityManagerFactory() {
    //JpaVendorAdapteradapter can be autowired as well if it's configured in application properties.
    HibernateJpaVendorAdapter vendorAdapter = new HibernateJpaVendorAdapter();
    vendorAdapter.setGenerateDdl(false);

    LocalContainerEntityManagerFactoryBean factory = new LocalContainerEntityManagerFactoryBean();
    factory.setJpaVendorAdapter(vendorAdapter);
    //Add package to scan for entities.
    factory.setPackagesToScan("com.company.domain");
    factory.setDataSource(dataSource);
    return factory;
}

@Bean
public PlatformTransactionManager transactionManager(EntityManagerFactory entityManagerFactory) {
    JpaTransactionManager txManager = new JpaTransactionManager();
    txManager.setEntityManagerFactory(entityManagerFactory);
    return txManager;
}

Also remember to add hibernate-entitymanager dependency to pom.xml otherwise EntityManagerFactory won't be found on classpath:

<dependency>
        <groupId>org.hibernate</groupId>
        <artifactId>hibernate-entitymanager</artifactId>
        <version>5.0.12.Final</version>
</dependency>

Shortcut for changing font size

You can chnage font size by ctrl + mousewheel.

OR

tools --> options --> environment --> font and color.

Detail with screenshot is mentonied here

How to convert java.util.Date to java.sql.Date?

With the other answer you may have troubles with the time info (compare the dates with unexpected results!)

I suggest:

java.util.Calendar cal = Calendar.getInstance();
java.util.Date utilDate = new java.util.Date(); // your util date
cal.setTime(utilDate);
cal.set(Calendar.HOUR_OF_DAY, 0);
cal.set(Calendar.MINUTE, 0);
cal.set(Calendar.SECOND, 0);
cal.set(Calendar.MILLISECOND, 0);    
java.sql.Date sqlDate = new java.sql.Date(cal.getTime().getTime()); // your sql date
System.out.println("utilDate:" + utilDate);
System.out.println("sqlDate:" + sqlDate);

Converting a factor to numeric without losing information R (as.numeric() doesn't seem to work)

First, factor consists of indices and levels. This fact is very very important when you are struggling with factor.

For example,

> z <- factor(letters[c(3, 2, 3, 4)])

# human-friendly display, but internal structure is invisible
> z
[1] c b c d
Levels: b c d

# internal structure of factor
> unclass(z)
[1] 2 1 2 3
attr(,"levels")
[1] "b" "c" "d"

here, z has 4 elements.
The index is 2, 1, 2, 3 in that order.
The level is associated with each index: 1 -> b, 2 -> c, 3 -> d.

Then, as.numeric converts simply the index part of factor into numeric.
as.character handles the index and levels, and generates character vector expressed by its level.

?as.numeric says that Factors are handled by the default method.

Error in <my code> : object of type 'closure' is not subsettable

In case of this similar error Warning: Error in $: object of type 'closure' is not subsettable [No stack trace available]

Just add corresponding package name using :: e.g.

instead of tags(....)

write shiny::tags(....)

How do I remove link underlining in my HTML email?

All email clients adjust the HTML and the CSS code you provide by their own rules:

e.g.: gmail removes everything but the inner HTML of the body tag.

1. for most other clients you can have a style-tag in your header

<style type="text/css">
    a {text-decoration: none !important;}
</style>

note: don't use CSS comments as YAHOO!Mail might cause trouble.

2. to be on the save side add the same code inline into the A tag as you did and an extra span tag as well (the style rules in a tags get often removed)

<a href="" style="text-decoration: none !important;">
    <span style="text-decoration: none !important;">
        text
    </span>
</a>

Execute an action when an item on the combobox is selected

Not an answer to the original question, but an example to the how-to-make-reusable and working custom renderers without breaking MVC :-)

// WRONG
public class DataWrapper {
   final Data data;
   final String description;
   public DataWrapper(Object data, String description) {
       this.data = data;
       this.description = description;
   }
   ....
   @Override
   public String toString() {
       return description;
   } 
}
// usage
myModel.add(new DataWrapper(data1, data1.getName());

It is wrong in a MVC environment, because it is mixing data and view: now the model doesn't contain the data but a wrapper which is introduced for view reasons. That's breaking separation of concerns and encapsulation (every class interacting with the model needs to be aware of the wrapped data).

The driving forces for breaking of rules were:

  • keep functionality of the default KeySelectionManager (which is broken by a custom renderer)
  • reuse of the wrapper class (can be applied to any data type)

As in Swing a custom renderer is the small coin designed to accomodate for custom visual representation, a default manager which can't cope is ... broken. Tweaking design just to accommodate for such a crappy default is the wrong way round, kind of upside-down. The correct is, to implement a coping manager.

While re-use is fine, doing so at the price of breaking the basic architecture is not a good bargin.

We have a problem in the presentation realm, let's solve it in the presentation realm with the elements designed to solve exactly that problem. As you might have guessed, SwingX already has such a solution :-)

In SwingX, the provider of a string representation is called StringValue, and all default renderers take such a StringValue to configure themselves:

StringValue sv = new StringValue() {
     @Override
     public String getString(Object value) {
        if (value instanceof Data) {
            return ((Data) value).getSomeProperty();
        }
        return TO_STRING.getString(value);
     }
};
DefaultListRenderer renderer = new DefaultListRenderer(sv);

As the defaultRenderer is-a StringValue (implemented to delegate to the given), a well-behaved implementation of KeySelectionManager now can delegate to the renderer to find the appropriate item:

public BetterKeySelectionManager implements KeySelectionManager {

     @Override
     public int selectionForKey(char ch, ComboBoxModel model) {

         ....
         if (getCellRenderer() instance of StringValue) {
              String text = ((StringValue) getCellRenderer()).getString(model.getElementAt(row));
              ....
         } 
     }

}

Outlined the approach because it is easily implementable even without using SwingX, simply define implement something similar and use it:

  • some provider of a string representation
  • a custom renderer which is configurable by that provider and guarantees to use it in configuring itself
  • a well-behaved keySelectionManager with queries the renderer for its string represention

All except the string provider is reusable as-is (that is exactly one implemenation of the custom renderer and the keySelectionManager). There can be general implementations of the string provider, f.i. those formatting value or using bean properties via reflection. And all without breaking basic rules :-)

What is the difference between task and thread?

You can use Task to specify what you want to do then attach that Task with a Thread. so that Task would be executed in that newly made Thread rather than on the GUI thread.

Use Task with the TaskFactory.StartNew(Action action). In here you execute a delegate so if you didn't use any thread it would be executed in the same thread (GUI thread). If you mention a thread you can execute this Task in a different thread. This is an unnecessary work cause you can directly execute the delegate or attach that delegate to a thread and execute that delegate in that thread. So don't use it. it's just unnecessary. If you intend to optimize your software this is a good candidate to be removed.

**Please note that the Action is a delegate.

Difference between try-catch and throw in java

In my limited experience with the following details.throws is a declaration that declares multiple exceptions that may occur but do not necessarily occur, throw is an action that can throw only one exception, typically a non-runtime exception, try catch is a block that catches exceptions that can be handled when an exception occurs in a method,this exception can be thrown.An exception can be understood as a responsibility that should be taken care of by the behavior that caused the exception, rather than by its upper callers. I hope my answer will help you

xampp MySQL does not start

You have two versions of mysql using the same port. 3306. Change the port.

How to change the mysql port for xampp?

  1. Stop the xampp server, if it is already running.
  2. Edit the value to "port" in xampp/mysql/bin/my.ini

Code:

Password = your_password   
port =  3306  --->  3307  
socket =  "/ xampp / mysql / mysql.sock"

and here also

Code:

The MySQL server 
[ mysqld ] 
port =  3306  --->  3307 
socket =  "/ xampp / mysql / mysql.sock"
2. Start mysql service

jQuery returning "parsererror" for ajax request

I was also getting "Request return with error:parsererror." in the javascript console. In my case it wasn´t a matter of Json, but I had to pass to the view text area a valid encoding.

  String encodedString = getEncodedString(text, encoding);
  view.setTextAreaContent(encodedString);

Most Pythonic way to provide global configuration variables in config.py?

A small variation on Husky's idea that I use. Make a file called 'globals' (or whatever you like) and then define multiple classes in it, as such:

#globals.py

class dbinfo :      # for database globals
    username = 'abcd'
    password = 'xyz'

class runtime :
    debug = False
    output = 'stdio'

Then, if you have two code files c1.py and c2.py, both can have at the top

import globals as gl

Now all code can access and set values, as such:

gl.runtime.debug = False
print(gl.dbinfo.username)

People forget classes exist, even if no object is ever instantiated that is a member of that class. And variables in a class that aren't preceded by 'self.' are shared across all instances of the class, even if there are none. Once 'debug' is changed by any code, all other code sees the change.

By importing it as gl, you can have multiple such files and variables that lets you access and set values across code files, functions, etc., but with no danger of namespace collision.

This lacks some of the clever error checking of other approaches, but is simple and easy to follow.

Newline in markdown table?

When you're exporting to HTML, using <br> works. However, if you're using pandoc to export to LaTeX/PDF as well, you should use grid tables:

+---------------+---------------+--------------------+
| Fruit         | Price         | Advantages         |
+===============+===============+====================+
| Bananas       | first line\   | first line\        |
|               | next line     | next line          |
+---------------+---------------+--------------------+
| Bananas       | first line\   | first line\        |
|               | next line     | next line          |
+---------------+---------------+--------------------+

Proxy with urllib2

In addition set the proxy for the command line session Open a command line where you might want to run your script

netsh winhttp set proxy YourProxySERVER:yourProxyPORT

run your script in that terminal.

WITH CHECK ADD CONSTRAINT followed by CHECK CONSTRAINT vs. ADD CONSTRAINT

Further to the above excellent comments about trusted constraints:

select * from sys.foreign_keys where is_not_trusted = 1 ;
select * from sys.check_constraints where is_not_trusted = 1 ;

An untrusted constraint, much as its name suggests, cannot be trusted to accurately represent the state of the data in the table right now. It can, however, but can be trusted to check data added and modified in the future.

Additionally, untrusted constraints are disregarded by the query optimiser.

The code to enable check constraints and foreign key constraints is pretty bad, with three meanings of the word "check".

ALTER TABLE [Production].[ProductCostHistory] 
WITH CHECK -- This means "Check the existing data in the table".
CHECK CONSTRAINT -- This means "enable the check or foreign key constraint".
[FK_ProductCostHistory_Product_ProductID] -- The name of the check or foreign key constraint, or "ALL".

Linux Script to check if process is running and act on the result

If you changed awk '{print $1}' to '{ $1=""; print $0}' you will get all processes except for the first as a result. It will start with the field separator (a space generally) but I don't recall killall caring. So:

#! /bin/bash

logfile="/var/oscamlog/oscam1check.log"

case "$(pidof oscam1 | wc -w)" in

0)  echo "oscam1 not running, restarting oscam1:     $(date)" >> $logfile
    /usr/local/bin/oscam1 -b -c /usr/local/etc/oscam1 -t /usr/local/tmp.oscam1 &
    ;;
2)  echo "oscam1 running, all OK:     $(date)" >> $logfile
    ;;
*)  echo "multiple instances of oscam1 running. Stopping & restarting oscam1:     $(date)" >> $logfile
    kill $(pidof oscam1 | awk '{ $1=""; print $0}')
    ;;
esac

It is worth noting that the pidof route seems to work fine for commands that have no spaces, but you would probably want to go back to a ps-based string if you were looking for, say, a python script named myscript that showed up under ps like

root 22415 54.0 0.4 89116 79076 pts/1 S 16:40 0:00 /usr/bin/python /usr/bin/myscript

Just an FYI

Git - Won't add files?

It's impossible (for me) to add the first file to an empty repository cloned from GitHub. You need to follow the link README, that GitHub suggests to create. After you create your first file online, you can work normally with git.

This happened to me Nov 17, 2016.

Convert Char to String in C

Using fgetc(fp) only to be able to call strcpy(buffer,c); doesn't seem right.

You could simply build this buffer on your own:

char buffer[MAX_SIZE_OF_MY_BUFFER];

int i = 0;
char ch;
while (i < MAX_SIZE_OF_MY_BUFFER - 1 && (ch = fgetc(fp)) != EOF) {
    buffer[i++] = ch;
}
buffer[i] = '\0';  // terminating character

Note that this relies on the fact that you will read less than MAX_SIZE_OF_MY_BUFFER characters

Converting File to MultiPartFile

If you can't import MockMultipartFile using

import org.springframework.mock.web.MockMultipartFile;

you need to add the below dependency into pom.xml:

<dependency>
    <groupId>org.springframework.boot</groupId>
    <artifactId>spring-boot-starter-test</artifactId>
    <scope>test</scope>
</dependency>

Jquery - Uncaught TypeError: Cannot use 'in' operator to search for '324' in

I fixed a similar error by adding the json dataType like so:

$.ajax({
    type: "POST",
    url: "someUrl",
    dataType: "json",
    data: {
        varname1 : "varvalue1",
        varname2 : "varvalue2"
    },
    success: function (data) {
        $.each(data, function (varname, varvalue){
            ...
        });  
    }
});

And in my controller I had to use double quotes around any strings like so (note: they have to be escaped in java):

@RequestMapping(value = "/someUrl", method=RequestMethod.POST)
@ResponseBody
public String getJsonData(@RequestBody String parameters) {
    // parameters = varname1=varvalue1&varname2=varvalue2
    String exampleData = "{\"somename1\":\"somevalue1\",\"somename2\":\"somevalue2\"}";
    return exampleData;
}

So, you could try using double quotes around your numbers if they are being used as strings (and remove that last comma):

[{"id":"50","name":"SEO"},{"id":"22","name":"LPO"}]

Woocommerce get products

Always use tax_query to get posts/products from a particular category or any other taxonomy. You can also get the products using ID/slug of particular taxonomy...

$the_query = new WP_Query( array(
    'post_type' => 'product',
    'tax_query' => array(
        array (
            'taxonomy' => 'product_cat',
            'field' => 'slug',
            'terms' => 'accessories',
        )
    ),
) );

while ( $the_query->have_posts() ) :
    $the_query->the_post();
    the_title(); echo "<br>";
endwhile;


wp_reset_postdata();

How can I check if a program exists from a Bash script?

There are a ton of options here, but I was surprised no quick one-liners. This is what I used at the beginning of my scripts:

[[ "$(command -v mvn)" ]] || { echo "mvn is not installed" 1>&2 ; exit 1; }
[[ "$(command -v java)" ]] || { echo "java is not installed" 1>&2 ; exit 1; }

This is based on the selected answer here and another source.

How to redirect 404 errors to a page in ExpressJS?

express-error-handler lets you specify custom templates, static pages, or error handlers for your errors. It also does other useful error-handling things that every app should implement, like protect against 4xx error DOS attacks, and graceful shutdown on unrecoverable errors. Here's how you do what you're asking for:

var errorHandler = require('express-error-handler'),
  handler = errorHandler({
    static: {
      '404': 'path/to/static/404.html'
    }
  });

// After all your routes...
// Pass a 404 into next(err)
app.use( errorHandler.httpError(404) );

// Handle all unhandled errors:
app.use( handler );

Or for a custom handler:

handler = errorHandler({
  handlers: {
    '404': function err404() {
      // do some custom thing here...
    }
  }
}); 

Or for a custom view:

handler = errorHandler({
  views: {
    '404': '404.jade'
  }
});

How can I change image tintColor in iOS and WatchKit

if you have any id for the SVG image, you can fill the colours with respect to the ID.

    let image = SVGKImage(named: "iconName")
    let svgIMGV = SVGKFastImageView(frame: self.imgView.frame)
         svgIMGV.image = image
          svgIMGV.fillTintColor(colorImage: UIColor.red, iconID: "Bank")
// Add in extension SVGKImageView
extension SVGKImageView {
 func fillTintColor(colorImage: UIColor, iconID: String) {
        if self.image != nil && self.image.caLayerTree != nil {
            print(self.image.caLayerTree.sublayers)
            guard let sublayers = self.image.caLayerTree.sublayers else { return }
            fillRecursively(sublayers: sublayers, color: colorImage, iconID: iconID)
        }
    }

     private func fillRecursively(sublayers: [CALayer], color: UIColor, iconID: String, hasFoundLayer: Bool) {
        var isLayerFound = false
        for layer in sublayers {
            if let l = layer as? CAShapeLayer {

                print(l.name)                
                //IF you want to color the specific shapelayer by id else remove the l.name  == "myID"  validation
                if let name =  l.name,  hasFoundLayer == true && name == "myID" {
                    self.colorThatImageWIthColor(color: color, layer: l)
                    print("Colouring FInished")
                }
            } else {
                if layer.name == iconID {
                    if let innerSublayer = layer.sublayers as? [CAShapeLayer] {
                        fillRecursively(sublayers: innerSublayer, color: color, iconID: iconID, hasFoundLayer: true )
                        print("FOund")
                    }
                } else {
                    if let l = layer as? CALayer, let sub = l.sublayers {
                        fillRecursively(sublayers: sub, color: color, iconID: iconID, hasFoundLayer: false)
                    }
                }
            }

        }
    }

    func colorThatImageWIthColor(color: UIColor, layer: CAShapeLayer) {
        if layer.strokeColor != nil {
            layer.strokeColor = color.cgColor
        }
        if layer.fillColor != nil {
            layer.fillColor = color.cgColor
        }
    }

}

OR Checkout this example.

https://github.com/ravisfortune/SVGDEMO

How to use opencv in using Gradle?

As per OpenCV docs(1), below steps using OpenCV manager is the recommended way to use OpenCV for production runs. But, OpenCV manager(2) is an additional install from Google play store. So, if you prefer a self contained apk(not using OpenCV manager) or is currently in development/testing phase, I suggest answer at https://stackoverflow.com/a/27421494/1180117.

Recommended steps for using OpenCV in Android Studio with OpenCV manager.

  1. Unzip OpenCV Android sdk downloaded from OpenCV.org(3)
  2. From File -> Import Module, choose sdk/java folder in the unzipped opencv archive.
  3. Update build.gradle under imported OpenCV module to update 4 fields to match your project's build.gradle a) compileSdkVersion b) buildToolsVersion c) minSdkVersion and 4) targetSdkVersion.
  4. Add module dependency by Application -> Module Settings, and select the Dependencies tab. Click + icon at bottom(or right), choose Module Dependency and select the imported OpenCV module.

As the final step, in your Activity class, add snippet below.

    public class SampleJava extends Activity  {

        private BaseLoaderCallback mLoaderCallback = new BaseLoaderCallback(this) {
        @Override
        public void onManagerConnected(int status) {
            switch(status) {
                case LoaderCallbackInterface.SUCCESS:
                    Log.i(TAG,"OpenCV Manager Connected");
                    //from now onwards, you can use OpenCV API
                    Mat m = new Mat(5, 10, CvType.CV_8UC1, new Scalar(0));
                    break;
                case LoaderCallbackInterface.INIT_FAILED:
                    Log.i(TAG,"Init Failed");
                    break;
                case LoaderCallbackInterface.INSTALL_CANCELED:
                    Log.i(TAG,"Install Cancelled");
                    break;
                case LoaderCallbackInterface.INCOMPATIBLE_MANAGER_VERSION:
                    Log.i(TAG,"Incompatible Version");
                    break;
                case LoaderCallbackInterface.MARKET_ERROR:
                    Log.i(TAG,"Market Error");
                    break;
                default:
                    Log.i(TAG,"OpenCV Manager Install");
                    super.onManagerConnected(status);
                    break;
            }
        }
    };

    @Override
    protected void onResume() {
        super.onResume();
        //initialize OpenCV manager
        OpenCVLoader.initAsync(OpenCVLoader.OPENCV_VERSION_2_4_9, this, mLoaderCallback);
    }
}

Note: You could only make OpenCV calls after you receive success callback on onManagerConnected method. During run, you will be prompted for installation of OpenCV manager from play store, if it is not already installed. During development, if you don't have access to play store or is on emualtor, use appropriate OpenCV manager apk present in apk folder under downloaded OpenCV sdk archive .

Pros

  • Apk size reduction by around 40 MB ( consider upgrades too ).
  • OpenCV manager installs optimized binaries for your hardware which could help speed.
  • Upgrades to OpenCV manager might save your app from bugs in OpenCV.
  • Different apps could share same OpenCV library.

Cons

  • End user experience - might not like a install prompt from with your application.

How do I connect to an MDF database file?

string sqlCon = @"Data Source=.\SQLEXPRESS;" +
                @"AttachDbFilename=|DataDirectory|\SampleDB.mdf;
                Integrated Security=True;
                Connect Timeout=30;
                User Instance=True";
SqlConnection Con = new SqlConnection(sqlCon);

The filepath should have |DataDirectory| which actually links to "current project directory\App_Data\" or "current project directory" and get the .mdf file.....Place the .mdf in either of these places and should work in visual studio 2010.And when you use the standalone application on production system, then the current path where the executable file is, should have the .mdf file.

How to set underline text on textview?

Try this,

tv.setPaintFlags(Paint.UNDERLINE_TEXT_FLAG);

IndexError: list index out of range and python

If you have a list with 53 items, the last one is thelist[52] because indexing starts at 0.

IndexError

The IndexError is raised when attempting to retrieve an index from a sequence (e.g. list, tuple), and the index isn’t found in the sequence. The Python documentation defines when this exception is raised:

Raised when a sequence subscript is out of range. (Source)

Here’s an example that raises the IndexError:

test = list(range(53))
test[53]

---------------------------------------------------------------------------
IndexError                                Traceback (most recent call last)
<ipython-input-6-7879607f7f36> in <module>
      1 test = list(range(53))
----> 2 test[53]

IndexError: list index out of range

The error message line for an IndexError doesn’t provide great information. See that there is a sequence reference that is out of range and what the type of the sequence is, a list in this case. That information, combined with the rest of the traceback, is usually enough to help quickly identify how to fix the issue.

Error: Cannot access file bin/Debug/... because it is being used by another process

I have faced the same issue, but none of the answers above helped me! I just simply closed my Visual Studio 2017 then re-run it, and It worked!

How best to include other scripts?

Using source or $0 will not give you the real path of your script. You could use the process id of the script to retrieve its real path

ls -l       /proc/$$/fd           | 
grep        "255 ->"            |
sed -e      's/^.\+-> //'

I am using this script and it has always served me well :)

Disable/enable an input with jQuery?

2018, without JQuery (ES6)

Disable all input:

[...document.querySelectorAll('input')].map(e => e.disabled = true);

Disable input with id="my-input"

document.getElementById('my-input').disabled = true;

The question is with JQuery, it's just FYI.

PHP Get name of current directory

Actually I found the best solution is the following:

$cur_dir = explode('\\', getcwd());
echo $cur_dir[count($cur_dir)-1];

if your dir is www\var\path\ Current_Path

then this returns Current_path

Ruby, Difference between exec, system and %x() or Backticks

They do different things. exec replaces the current process with the new process and never returns. system invokes another process and returns its exit value to the current process. Using backticks invokes another process and returns the output of that process to the current process.

Authenticated HTTP proxy with Java

Try this runner I wrote. It could be helpful.

import java.io.InputStream;
import java.lang.reflect.Method;
import java.net.Authenticator;
import java.net.PasswordAuthentication;
import java.net.URL;
import java.net.URLConnection;
import java.util.Scanner;

public class ProxyAuthHelper {

    public static void main(String[] args) throws Exception {
        String tmp = System.getProperty("http.proxyUser", System.getProperty("https.proxyUser"));
        if (tmp == null) {
            System.out.println("Proxy username: ");
            tmp = new Scanner(System.in).nextLine();
        }
        final String userName = tmp;

        tmp = System.getProperty("http.proxyPassword", System.getProperty("https.proxyPassword"));
        if (tmp == null) {
            System.out.println("Proxy password: ");
            tmp = new Scanner(System.in).nextLine();
        }
        final char[] password = tmp.toCharArray();

        Authenticator.setDefault(new Authenticator() {
            @Override
            protected PasswordAuthentication getPasswordAuthentication() {
                System.out.println("\n--------------\nProxy auth: " + userName);
                return new PasswordAuthentication (userName, password);
            }

         });

        Class<?> clazz = Class.forName(args[0]);
        Method method = clazz.getMethod("main", String[].class);
        String[] newArgs = new String[args.length - 1];
        System.arraycopy(args, 1, newArgs, 0, newArgs.length);
        method.invoke(null, new Object[]{newArgs});
    }

}

Why is setTimeout(fn, 0) sometimes useful?

Since it is being passed a duration of 0, I suppose it is in order to remove the code passed to the setTimeout from the flow of execution. So if it's a function that could take a while, it won't prevent the subsequent code from executing.

Convert Decimal to Varchar

If you are using SQL Server 2012, 2014 or newer, use the Format Function instead:

select Format( decimalColumnName ,'FormatString','en-US' )

Review the Microsoft topic and .NET format syntax for how to define the format string.

An example for this question would be:

select Format( MyDecimalColumn ,'N','en-US' )

Request redirect to /Account/Login?ReturnUrl=%2f since MVC 3 install on server

If nothing works then add authentication mode="Windows" in your system.web attribute in your Web.Config file. hope it will work for you.

jquery .live('click') vs .click()

If you need simplify code then live is better in the most cases. If you need to get the best performance then delegate will always better than live. bind (click) vs delegate isn't so simple question (if you have a lot of similar items then delegate will be better).

Viewing local storage contents on IE

Edge (as opposed to IE11) has a better UI for Local storage / Session storage and cookies:

  • Open Dev tools (F12)
  • Go to Debugger tab
  • Click the folder icon to show a list of resources - opens in a separate tab

Dev tools screenshot

Getting list of files in documents folder

This solution works with Swift 4 (Xcode 9.2) and also with Swift 5 (Xcode 10.2.1+):

let fileManager = FileManager.default
let documentsURL = fileManager.urls(for: .documentDirectory, in: .userDomainMask)[0]
do {
    let fileURLs = try fileManager.contentsOfDirectory(at: documentsURL, includingPropertiesForKeys: nil)
    // process files
} catch {
    print("Error while enumerating files \(documentsURL.path): \(error.localizedDescription)")
}

Here's a reusable FileManager extension that also lets you skip or include hidden files in the results:

import Foundation

extension FileManager {
    func urls(for directory: FileManager.SearchPathDirectory, skipsHiddenFiles: Bool = true ) -> [URL]? {
        let documentsURL = urls(for: directory, in: .userDomainMask)[0]
        let fileURLs = try? contentsOfDirectory(at: documentsURL, includingPropertiesForKeys: nil, options: skipsHiddenFiles ? .skipsHiddenFiles : [] )
        return fileURLs
    }
}

// Usage
print(FileManager.default.urls(for: .documentDirectory) ?? "none")

Is the LIKE operator case-sensitive with MSSQL Server?

You can change from the property of every item.

case sensitive

How to count the number of files in a directory using Python

def directory(path,extension):
  list_dir = []
  list_dir = os.listdir(path)
  count = 0
  for file in list_dir:
    if file.endswith(extension): # eg: '.txt'
      count += 1
  return count

PHP "pretty print" json_encode

And for PHP 5.3, you can use this function, which can be embedded in a class or used in procedural style:

http://svn.kd2.org/svn/misc/libs/tools/json_readable_encode.php

Laravel 4: Redirect to a given url

Both Redirect::to() and Redirect::away() should work.

Difference

Redirect::to() does additional URL checks and generations. Those additional steps are done in Illuminate\Routing\UrlGenerator and do the following, if the passed URL is not a fully valid URL (even with protocol):

Determines if URL is secure
rawurlencode() the URL
trim() URL

src : https://medium.com/@zwacky/laravel-redirect-to-vs-redirect-away-dd875579951f

WebSockets protocol vs HTTP

For the TL;DR, here are 2 cents and a simpler version for your questions:

  1. WebSockets provides these benefits over HTTP:

    • Persistent stateful connection for the duration of the connection
    • Low latency: near-real-time communication between server/client due to no overhead of reestablishing connections for each request as HTTP requires.
    • Full duplex: both server and client can send/receive simultaneously
  2. WebSocket and HTTP protocol have been designed to solve different problems, I.E. WebSocket was designed to improve bi-directional communication whereas HTTP was designed to be stateless, distributed using a request/response model. Other than sharing the ports for legacy reasons (firewall/proxy penetration), there isn't much common ground to combine them into one protocol.

How to prevent auto-closing of console after the execution of batch file

Easy, add cmd to your last line of bat, BUT! if you reset or clear your system path, you must start your cmd with the full path, like:

%windir%\system32\cmd.exe

For example, I have a bat file to reset jdk to old version like this:

PATH=C:\Program Files\Java\jdk1.6.0_45\bin;C:\apache-ant-1.7.1\bin
SET JAVA_HOME=C:\Program Files\Java\jdk1.6.0_45
%windir%\system32\cmd.exe

since I reset the system path, I have to run cmd with the full path, or the system can't find cmd.exe, it will fail to run cmd, and just close the window, and you can't see the error msg.

Android: combining text & image on a Button or ImageButton

There's a much better solution for this problem.

Just take a normal Button and use the drawableLeft and the gravity attributes.

<Button
  android:layout_width="fill_parent"
  android:layout_height="wrap_content"
  android:drawableLeft="@drawable/my_btn_icon"
  android:gravity="left|center_vertical" />

This way you get a button which displays a icon in the left side of the button and the text at the right site of the icon vertical centered.

Android Viewpager as Image Slide Gallery

I made a library named AndroidImageSlider, you can have a try.

enter image description here

VB.NET: how to prevent user input in a ComboBox

this is the most simple way but it works for me with a ComboBox1 name

SOLUTION on 3 Basic STEPS:

step 1.

Declare a variable at the beginning of your form which will hold the original text value of the ComboBox. Example:

     Dim xCurrentTextValue as string

step 2.

Create the event combobox1 key down and Assign to xCurrentTextValue variable the current text of the combobox if any key diferrent than "ENTER" is pressed the combobox text value keeps the original text value

Example:

Private Sub ComboBox1_KeyDown(sender As Object, e As KeyEventArgs) Handles ComboBox1.KeyDown

    xCurrentTextValue = ComboBox1.Text

    If e.KeyCode <> Keys.Enter Then
        Me.ComboBox1.Text = xCmbItem
    End If

End Sub

step 3.

Validate the when the combo text is changed if len(xcurrenttextvalue)> 0 or is different than nothing then the combobox1 takes the xcurrenttextvalue variable value

Private Sub ComboBox1_TextChanged(sender As Object, e As EventArgs) Handles ComboBox1.TextChanged
    If Len(xCurrentTextValue) > 0 Then
        Me.ComboBox1.Text = xCurrentTextValue

    End If
End Sub

========================================================== that's it,

Originally I only tried the step number 2, but I have problems when you press the DEL key and DOWN arrow key, also for some reason it didn't validate the keydown event unless I display any message box


!Sorry, this is a correction on step number 2, I forgot to change the variable xCmbItem to xCurrentTextValue, xCmbItem it was used for my personal use

THIS IS THE CORRECT CODE

xCurrentTextValue = ComboBox1.Text

If e.KeyCode <> Keys.Enter Then
    Me.ComboBox1.Text = xCurrentTextValue
End If

SyntaxError of Non-ASCII character

You should define source code encoding, add this to the top of your script:

# -*- coding: utf-8 -*-

The reason why it works differently in console and in the IDE is, likely, because of different default encodings set. You can check it by running:

import sys
print sys.getdefaultencoding()

Also see:

How do I concatenate two strings in Java?

you can use stringbuffer, stringbuilder, and as everyone before me mentioned, "+". I'm not sure how fast "+" is (I think it is the fastest for shorter strings), but for longer I think builder and buffer are about equal (builder is slightly faster because it's not synchronized).

Remove new lines from string and replace with one empty space

A few comments on the accepted answer:

The + means "1 or more". I don't think you need to repeat \s. I think you can simply write '/\s+/'.

Also, if you want to remove whitespace first and last in the string, add trim.

With these modifications, the code would be:

$string = preg_replace('/\s+/', ' ', trim($string));

CASCADE DELETE just once

I took Joe Love's answer and rewrote it using the IN operator with sub-selects instead of = to make the function faster (according to Hubbitus's suggestion):

create or replace function delete_cascade(p_schema varchar, p_table varchar, p_keys varchar, p_subquery varchar default null, p_foreign_keys varchar[] default array[]::varchar[])
 returns integer as $$
declare

    rx record;
    rd record;
    v_sql varchar;
    v_subquery varchar;
    v_primary_key varchar;
    v_foreign_key varchar;
    v_rows integer;
    recnum integer;

begin

    recnum := 0;
    select ccu.column_name into v_primary_key
        from
        information_schema.table_constraints  tc
        join information_schema.constraint_column_usage AS ccu ON ccu.constraint_name = tc.constraint_name and ccu.constraint_schema=tc.constraint_schema
        and tc.constraint_type='PRIMARY KEY'
        and tc.table_name=p_table
        and tc.table_schema=p_schema;

    for rx in (
        select kcu.table_name as foreign_table_name, 
        kcu.column_name as foreign_column_name, 
        kcu.table_schema foreign_table_schema,
        kcu2.column_name as foreign_table_primary_key
        from information_schema.constraint_column_usage ccu
        join information_schema.table_constraints tc on tc.constraint_name=ccu.constraint_name and tc.constraint_catalog=ccu.constraint_catalog and ccu.constraint_schema=ccu.constraint_schema 
        join information_schema.key_column_usage kcu on kcu.constraint_name=ccu.constraint_name and kcu.constraint_catalog=ccu.constraint_catalog and kcu.constraint_schema=ccu.constraint_schema
        join information_schema.table_constraints tc2 on tc2.table_name=kcu.table_name and tc2.table_schema=kcu.table_schema
        join information_schema.key_column_usage kcu2 on kcu2.constraint_name=tc2.constraint_name and kcu2.constraint_catalog=tc2.constraint_catalog and kcu2.constraint_schema=tc2.constraint_schema
        where ccu.table_name=p_table  and ccu.table_schema=p_schema
        and TC.CONSTRAINT_TYPE='FOREIGN KEY'
        and tc2.constraint_type='PRIMARY KEY'
)
    loop
        v_foreign_key := rx.foreign_table_schema||'.'||rx.foreign_table_name||'.'||rx.foreign_column_name;
        v_subquery := 'select "'||rx.foreign_table_primary_key||'" as key from '||rx.foreign_table_schema||'."'||rx.foreign_table_name||'"
             where "'||rx.foreign_column_name||'"in('||coalesce(p_keys, p_subquery)||') for update';
        if p_foreign_keys @> ARRAY[v_foreign_key] then
            --raise notice 'circular recursion detected';
        else
            p_foreign_keys := array_append(p_foreign_keys, v_foreign_key);
            recnum:= recnum + delete_cascade(rx.foreign_table_schema, rx.foreign_table_name, null, v_subquery, p_foreign_keys);
            p_foreign_keys := array_remove(p_foreign_keys, v_foreign_key);
        end if;
    end loop;

    begin
        if (coalesce(p_keys, p_subquery) <> '') then
            v_sql := 'delete from '||p_schema||'."'||p_table||'" where "'||v_primary_key||'"in('||coalesce(p_keys, p_subquery)||')';
            --raise notice '%',v_sql;
            execute v_sql;
            get diagnostics v_rows = row_count;
            recnum := recnum + v_rows;
        end if;
        exception when others then recnum=0;
    end;

    return recnum;

end;
$$
language PLPGSQL;

How to remove a build from itunes connect?

Choose the build

The answer is that you Mouse over the icon for your build and at the end of the line you'll see a little colored minus in a circle. This removes the build and you can now click on the + sign and choose a new build for submitting.

It is an unbelievably complicated web page with tricks and gizmos to do the thing you want. I'm sure Steve never saw this page or tried to use it.

Surely it's better practice to design the screen so that you can see the options all the time, not to have the screen change depending on whether you have an app in review or not!

How do I resolve `The following packages have unmet dependencies`

First of all try this

sudo apt-get update
sudo apt-get clean
sudo apt-get autoremove

If error still persists then do this

sudo apt --fix-broken install
sudo apt-get update && sudo apt-get upgrade
sudo dpkg --configure -a
sudo apt-get install -f

Afterwards try this again:

sudo apt-get install npm

But if it still couldn't resolve issues check for the dependencies using sudo dpkg --configure -a and remove them one-by-one . Let's say dependencies are on npm then go for this ,

sudo apt-get remove nodejs
sudo apt-get remove npm

Then go to /etc/apt/sources.list.d and remove any node list if you have. Then do a

sudo apt-get update

Then check for the dependencies problem again using sudo dpkg --configure -a and if it's all clear then you are done . Later on install npm again using this

v=8   # set to 4, 5, 6, ... as needed
curl -sL https://deb.nodesource.com/setup_$v.x | sudo -E bash -

Then install the Node.js package.

sudo apt-get install -y nodejs

The answer above will work for general cases also(for dependencies on other packages like django ,etc) just after first two processes use the same process for the package you are facing dependency with.

docker mounting volumes on host

VOLUME is used in Dockerfile to expose the volume to be used by other containers. Example, create Dockerfile as:

FROM ubuntu:14.04

RUN mkdir /myvol  
RUN echo "hello world" > /myvol/greeting  
VOLUME /myvol

build the image:

$ docker build -t testing_volume .

Run the container, say container1:

$ docker run -it <image-id of above image> bash

Now run another container with volumes-from option as (say-container2)

$ docker run -it --volumes-from <id-of-above-container> ubuntu:14.04 bash

You will get all data from container1 /myvol directory into container2 at same location.

-v option is given at run time of container which is used to mount container's directory on host. It is simple to use, just provide -v option with argument as <host-path>:<container-path>. The whole command may be as $ docker run -v <host-path>:<container-path> <image-id>

Access restriction: The type 'Application' is not API (restriction on required library rt.jar)

Remove Existing/Configured System Library: Eclipse(IDE) -> Project Explorer -> Project Name-> (Option) Build Path -> Configure Build Path -> Java Build Path -> Libraries -> (Select) JRE System Library [(For me)jre1.8.0_231] -> Remove.

Currently you are at same location: Eclipse(IDE) -> Project Explorer -> Project Name-> (Option) Build Path -> Configure Build Path -> Java Build Path -> Libraries

Now Add Same System Library Again: Add Library -> JRE System Library -> Workspace default JRE ((For me)jre1.8.0_231) -> Finish -> Apply -> Close.

Now wait to finish it.

Push to GitHub without a password using ssh-key

Additionally for gists, it seems you must leave out the username

git remote set-url origin [email protected]:<Project code>

How to vertically align text inside a flexbox?

RESULT

enter image description here

HTML

<ul class="list">
  <li>This is the text</li>
  <li>This is another text</li>
  <li>This is another another text</li>
</ul>

Use align-items instead of align-self and I also added flex-direction to column.

CSS

* {
  padding: 0;
  margin: 0;
  box-sizing: border-box;
}

html,
body {
  height: 100%;
}

.list {
  display: flex;
  justify-content: center;
  flex-direction: column;  /* <--- I added this */
  align-items: center;   /* <--- Change here */
  height: 100px;
  width: 100%;
  background: silver;
}

.list li {  
  background: gold;
  height: 20%; 
}

Convert List to Pandas Dataframe Column

Use:

L = ['Thanks You', 'Its fine no problem', 'Are you sure']

#create new df 
df = pd.DataFrame({'col':L})
print (df)

                   col
0           Thanks You
1  Its fine no problem
2         Are you sure

df = pd.DataFrame({'oldcol':[1,2,3]})

#add column to existing df 
df['col'] = L
print (df)
   oldcol                  col
0       1           Thanks You
1       2  Its fine no problem
2       3         Are you sure

Thank you DYZ:

#default column name 0
df = pd.DataFrame(L)
print (df)
                     0
0           Thanks You
1  Its fine no problem
2         Are you sure

Usage of $broadcast(), $emit() And $on() in AngularJS

  • Broadcast: We can pass the value from parent to child (i.e parent -> child controller.)
  • Emit: we can pass the value from child to parent (i.e.child ->parent controller.)
  • On: catch the event dispatched by $broadcast or $emit.

git add remote branch

If the remote branch already exists then you can (probably) get away with..

git checkout branch_name

and git will automatically set up to track the remote branch with the same name on origin.

Java Try Catch Finally blocks without Catch

Don't you try it with that program? It'll goto finally block and executing the finally block, but, the exception won't be handled. But, that exception can be overruled in the finally block!

What is Unicode, UTF-8, UTF-16?

Unicode is a standard which maps the characters in all languages to a particular numeric value called Code Points. The reason it does this is that it allows different encodings to be possible using the same set of code points.

UTF-8 and UTF-16 are two such encodings. They take code points as input and encodes them using some well-defined formula to produce the encoded string.

Choosing a particular encoding depends upon your requirements. Different encodings have different memory requirements and depending upon the characters that you will be dealing with, you should choose the encoding which uses the least sequences of bytes to encode those characters.

For more in-depth details about Unicode, UTF-8 and UTF-16, you can check out this article,

What every programmer should know about Unicode

MySQL - SELECT all columns WHERE one column is DISTINCT

Select the datecolumn of month so that u can get only one row per link, e.g.:

select link, min(datecolumn) from posted WHERE ad='$key' ORDER BY day, month

Good luck............

Or

u if you have date column as timestamp convert the format to date and perform distinct on link so that you can get distinct link values based on date instead datetime

psql - save results of command to a file

The psql \o command was already described by jhwist.

An alternative approach is using the COPY TO command to write directly to a file on the server. This has the advantage that it's dumped in an easy-to-parse format of your choice -- rather than psql's tabulated format. It's also very easy to import to another table/database using COPY FROM.

NB! This requires superuser privileges and will write to a file on the server.

Example: COPY (SELECT foo, bar FROM baz) TO '/tmp/query.csv' (format csv, delimiter ';')

Creates a CSV file with ';' as the field separator.

As always, see the documentation for details

Validate IPv4 address in Java

There is also an undocumented utility class sun.net.util.IPAddressUtil, which you should not actually use, although it might be useful in a quick one-off, throw-away utility:

boolean isIP = IPAddressUtil.isIPv4LiteralAddress(ipAddressString);

Internally, this is the utility class InetAddress uses to parse IP addresses.

Note that this will return true for strings like "123", which, technically are valid IPv4 addresses, just not in dot-decimal notation.

How do I compile and run a program in Java on my Mac?

You need to make sure that a mac compatible version of java exists on your computer. Do java -version from terminal to check that. If not, download the apple jdk from the apple website. (Sun doesn't make one for apple themselves, IIRC.)

From there, follow the same command line instructions from compiling your program that you would use for java on any other platform.

How can I delete all cookies with JavaScript?

On the face of it, it looks okay - if you call eraseCookie() on each cookie that is read from document.cookie, then all of your cookies will be gone.

Try this:

var cookies = document.cookie.split(";");
for (var i = 0; i < cookies.length; i++)
  eraseCookie(cookies[i].split("=")[0]);

All of this with the following caveat:

  • JavaScript cannot remove cookies that have the HttpOnly flag set.

$(document).ready(function(){ Uncaught ReferenceError: $ is not defined

I know this is an old question, and most people have replied with good answers. But for reference and hopefully saving somebody else's time. Check if your function:

$(document).ready(function(){}

is being called after you have loaded the JQuery library

Writing a VLOOKUP function in vba

Have you tried:

Dim result As String 
Dim sheet As Worksheet 
Set sheet = ActiveWorkbook.Sheets("Data") 
result = Application.WorksheetFunction.VLookup(sheet.Range("AN2"), sheet.Range("AA9:AF20"), 5, False)

Declare global variables in Visual Studio 2010 and VB.NET

small remark: I am using modules in webbased application (asp.net). I need to remember that everything I store in the variables on the module are seen by everyone in the application, read website. Not only in my session. If i try to add up a calculation in my session I need to make an array to filter the numbers for my session and for others. Modules is a great way to work but need concentration on how to use it.

To help against mistakes: classes are send to the

CarbageCollector

when the page is finished. My modules stay alive (as long as the application is not ended or restarted) and I can reuse the data in it. I use this to save data that sometimes is lost because of the sessionhandling by IIS.

IIS Form auth

and

IIS_session

are not in sync, and with my module I pull back data that went over de cliff.

Sizing elements to percentage of screen width/height

There is many way to do this.

1. Using MediaQuery : Its return fullscreen of your device including appbar,toolbar

 Container(
        width: MediaQuery.of(context).size.width * 0.50,
        height: MediaQuery.of(context).size.height*0.50, 
        color: Colors.blueAccent[400],
 )

enter image description here


2. Using Expanded : You can set width/height in ratio

 Container(
        height: MediaQuery.of(context).size.height * 0.50,
        child: Row(
          children: <Widget>[
            Expanded(
              flex: 70,
              child: Container(
                color: Colors.lightBlue[400],
              ),
            ),
            Expanded(
              flex: 30,
              child: Container(
                color: Colors.deepPurple[800],
              ),
            )
          ],
        ),
    )

enter image description here



3. Others Like Flexible and AspectRatio and FractionallySizedBox

Converting ArrayList to HashMap

[edited]

using your comment about productCode (and assuming product code is a String) as reference...

 for(Product p : productList){
        s.put(p.getProductCode() , p);
    }

Difference between static STATIC_URL and STATIC_ROOT on Django

STATICFILES_DIRS: You can keep the static files for your project here e.g. the ones used by your templates.

STATIC_ROOT: leave this empty, when you do manage.py collectstatic, it will search for all the static files on your system and move them here. Your static file server is supposed to be mapped to this folder wherever it is located. Check it after running collectstatic and you'll find the directory structure django has built.

--------Edit----------------

As pointed out by @DarkCygnus, STATIC_ROOT should point at a directory on your filesystem, the folder should be empty since it will be populated by Django.

STATIC_ROOT = os.path.join(BASE_DIR, 'staticfiles')

or

STATIC_ROOT = '/opt/web/project/static_files'

--------End Edit -----------------

STATIC_URL: '/static/' is usually fine, it's just a prefix for static files.

Error "Metadata file '...\Release\project.dll' could not be found in Visual Studio"

Did you check the Configuration manager settings? In the project settings dialog top right corner.

Sometimes it happens that between all the release entries a debug entry comes in. If so, the auto dependency created by the dependency graph of the solution gets all confused.

Node.js getaddrinfo ENOTFOUND

in my case error was because of using incorrect host value was

  var options = {
    host: 'graph.facebook.com/v2.12/',
    path: path
  }

should be

  var options = {
    host: 'graph.facebook.com',
    path: path
  }

so anything after .com or .net etc should be moved to path parameter value

How can I use different certificates on specific connections?

I've had to do something like this when using commons-httpclient to access an internal https server with a self-signed certificate. Yes, our solution was to create a custom TrustManager that simply passed everything (logging a debug message).

This comes down to having our own SSLSocketFactory that creates SSL sockets from our local SSLContext, which is set up to have only our local TrustManager associated with it. You don't need to go near a keystore/certstore at all.

So this is in our LocalSSLSocketFactory:

static {
    try {
        SSL_CONTEXT = SSLContext.getInstance("SSL");
        SSL_CONTEXT.init(null, new TrustManager[] { new LocalSSLTrustManager() }, null);
    } catch (NoSuchAlgorithmException e) {
        throw new RuntimeException("Unable to initialise SSL context", e);
    } catch (KeyManagementException e) {
        throw new RuntimeException("Unable to initialise SSL context", e);
    }
}

public Socket createSocket(String host, int port) throws IOException, UnknownHostException {
    LOG.trace("createSocket(host => {}, port => {})", new Object[] { host, new Integer(port) });

    return SSL_CONTEXT.getSocketFactory().createSocket(host, port);
}

Along with other methods implementing SecureProtocolSocketFactory. LocalSSLTrustManager is the aforementioned dummy trust manager implementation.

How to move all HTML element children to another parent using JavaScript?

Modern way:

newParent.append(...oldParent.childNodes);
  1. .append is the replacement for .appendChild. The main difference is that it accepts multiple nodes at once and even plain strings, like .append('hello!')
  2. oldParent.childNodes is iterable so it can be spread with ... to become multiple parameters of .append()

Compatibility tables of both (in short: Edge 17+, Safari 10+):

How to implement a binary tree?

Simple implementation of BST in Python

class TreeNode:
    def __init__(self, value):
        self.left = None
        self.right = None
        self.data = value

class Tree:
    def __init__(self):
        self.root = None

    def addNode(self, node, value):
        if(node==None):
            self.root = TreeNode(value)
        else:
            if(value<node.data):
                if(node.left==None):
                    node.left = TreeNode(value)
                else:
                    self.addNode(node.left, value)
            else:
                if(node.right==None):
                    node.right = TreeNode(value)
                else:
                    self.addNode(node.right, value)

    def printInorder(self, node):
        if(node!=None):
            self.printInorder(node.left)
            print(node.data)
            self.printInorder(node.right)

def main():
    testTree = Tree()
    testTree.addNode(testTree.root, 200)
    testTree.addNode(testTree.root, 300)
    testTree.addNode(testTree.root, 100)
    testTree.addNode(testTree.root, 30)
    testTree.printInorder(testTree.root)

How to round up a number in Javascript?

I've been using @AndrewMarshall answer for a long time, but found some edge cases. The following tests doesn't pass:

equals(roundUp(9.69545, 4), 9.6955);
equals(roundUp(37.760000000000005, 4), 37.76);
equals(roundUp(5.83333333, 4), 5.8333);

Here is what I now use to have round up behave correctly:

// Closure
(function() {
  /**
   * Decimal adjustment of a number.
   *
   * @param {String}  type  The type of adjustment.
   * @param {Number}  value The number.
   * @param {Integer} exp   The exponent (the 10 logarithm of the adjustment base).
   * @returns {Number} The adjusted value.
   */
  function decimalAdjust(type, value, exp) {
    // If the exp is undefined or zero...
    if (typeof exp === 'undefined' || +exp === 0) {
      return Math[type](value);
    }
    value = +value;
    exp = +exp;
    // If the value is not a number or the exp is not an integer...
    if (isNaN(value) || !(typeof exp === 'number' && exp % 1 === 0)) {
      return NaN;
    }
    // If the value is negative...
    if (value < 0) {
      return -decimalAdjust(type, -value, exp);
    }
    // Shift
    value = value.toString().split('e');
    value = Math[type](+(value[0] + 'e' + (value[1] ? (+value[1] - exp) : -exp)));
    // Shift back
    value = value.toString().split('e');
    return +(value[0] + 'e' + (value[1] ? (+value[1] + exp) : exp));
  }

  // Decimal round
  if (!Math.round10) {
    Math.round10 = function(value, exp) {
      return decimalAdjust('round', value, exp);
    };
  }
  // Decimal floor
  if (!Math.floor10) {
    Math.floor10 = function(value, exp) {
      return decimalAdjust('floor', value, exp);
    };
  }
  // Decimal ceil
  if (!Math.ceil10) {
    Math.ceil10 = function(value, exp) {
      return decimalAdjust('ceil', value, exp);
    };
  }
})();

// Round
Math.round10(55.55, -1);   // 55.6
Math.round10(55.549, -1);  // 55.5
Math.round10(55, 1);       // 60
Math.round10(54.9, 1);     // 50
Math.round10(-55.55, -1);  // -55.5
Math.round10(-55.551, -1); // -55.6
Math.round10(-55, 1);      // -50
Math.round10(-55.1, 1);    // -60
Math.round10(1.005, -2);   // 1.01 -- compare this with Math.round(1.005*100)/100 above
Math.round10(-1.005, -2);  // -1.01
// Floor
Math.floor10(55.59, -1);   // 55.5
Math.floor10(59, 1);       // 50
Math.floor10(-55.51, -1);  // -55.6
Math.floor10(-51, 1);      // -60
// Ceil
Math.ceil10(55.51, -1);    // 55.6
Math.ceil10(51, 1);        // 60
Math.ceil10(-55.59, -1);   // -55.5
Math.ceil10(-59, 1);       // -50

Source: https://developer.mozilla.org/en-US/docs/Web/JavaScript/Reference/Global_Objects/Math/round

How do we check if a pointer is NULL pointer?

The compiler must provide a consistent type system, and provide a set of standard conversions. Neither the integer value 0 nor the NULL pointer need to be represented by all-zero bits, but the compiler must take care of converting the "0" token in the input file to the correct representation for integer zero, and the cast to pointer type must convert from integer to pointer representation.

The implication of this is that

void *p;
memset(&p, 0, sizeof p);
if(p) { ... }

is not guaranteed to behave the same on all target systems, as you are making an assumption about the bit pattern here.

As an example, I have an embedded platform that has no memory protection, and keeps the interrupt vectors at address 0, so by convention, integers and pointers are XORed with 0x2000000 when converted, which leaves (void *)0 pointing at an address that generates a bus error when dereferenced, however testing the pointer with an if statement will return it to integer representation first, which is then all-zeros.

How do I center list items inside a UL element?

A more modern way is to use flexbox:

_x000D_
_x000D_
ul{_x000D_
  list-style-type:none;_x000D_
  display:flex;_x000D_
  justify-content: center;_x000D_
_x000D_
}_x000D_
ul li{_x000D_
  display: list-item;_x000D_
  background: black;_x000D_
  padding: 5px 10px;_x000D_
  color:white;_x000D_
  margin: 0 3px;_x000D_
}_x000D_
div{_x000D_
  background: wheat;_x000D_
}
_x000D_
<div>_x000D_
<ul>_x000D_
  <li>One</li>_x000D_
  <li>Two</li>_x000D_
  <li>Three</li>_x000D_
</ul>  _x000D_
_x000D_
</div>
_x000D_
_x000D_
_x000D_

Async always WaitingForActivation

For my answer, it is worth remembering that the TPL (Task-Parallel-Library), Task class and TaskStatus enumeration were introduced prior to the async-await keywords and the async-await keywords were not the original motivation of the TPL.

In the context of methods marked as async, the resulting Task is not a Task representing the execution of the method, but a Task for the continuation of the method.

This is only able to make use of a few possible states:

  • Canceled
  • Faulted
  • RanToCompletion
  • WaitingForActivation

I understand that Runningcould appear to have been a better default than WaitingForActivation, however this could be misleading, as the majority of the time, an async method being executed is not actually running (i.e. it may be await-ing something else). The other option may have been to add a new value to TaskStatus, however this could have been a breaking change for existing applications and libraries.

All of this is very different to when making use of Task.Run which is a part of the original TPL, this is able to make use of all the possible values of the TaskStatus enumeration.

If you wish to keep track of the status of an async method, take a look at the IProgress(T) interface, this will allow you to report the ongoing progress. This blog post, Async in 4.5: Enabling Progress and Cancellation in Async APIs will provide further information on the use of the IProgress(T) interface.

Using other keys for the waitKey() function of opencv

I too found this perplexing. I'm running Ubuntu 18 and found the following: If the cv.imshow window has focus, you'll get one set of values in the terminal - like the ASCII values discussed above.

If the Terminal has focus, you'll see different values. IE- you'll see "a" when you press the a key (instead of ASCII value 97) and "^]" instead of "27" when you press Escape.

I didn't see the 6 digit numbers mentioned above in either case and I used similar code. It seems the value for waitKey is the polling period in mS. The dots illustrate this.

Run this snippet and press keys while focus is on the test image, then click on the terminal window and press the same keys.

    import cv2
    img = cv2.imread('test.jpg') 
    cv2.imshow('Your test image', img)

    while(1):
      k = cv2.waitKey(300)
      if k == 27:
        break
      elif k==-1:
       print "."
       continue
      else:
        print k 

Running conda with proxy

You can configure a proxy with conda by adding it to the .condarc, like

proxy_servers:
    http: http://user:[email protected]:8080
    https: https://user:[email protected]:8080

or set the HTTP_PROXY and HTTPS_PROXY environment variables. Note that in your case you need to add the scheme to the proxy url, like https://proxy-us.bla.com:123.

See http://conda.pydata.org/docs/config.html#configure-conda-for-use-behind-a-proxy-server.

VBA copy rows that meet criteria to another sheet

After formatting the previous answer to my own code, I have found an efficient way to copy all necessary data if you are attempting to paste the values returned via AutoFilter to a separate sheet.

With .Range("A1:A" & LastRow)
    .Autofilter Field:=1, Criteria1:="=*" & strSearch & "*"
    .Offset(1,0).SpecialCells(xlCellTypeVisible).Cells.Copy
    Sheets("Sheet2").activate
    DestinationRange.PasteSpecial
End With

In this block, the AutoFilter finds all of the rows that contain the value of strSearch and filters out all of the other values. It then copies the cells (using offset in case there is a header), opens the destination sheet and pastes the values to the specified range on the destination sheet.

generate days from date range

thx Pentium10 - you made me join stackoverflow :) - this is my porting to msaccess - think it'll work on any version:

SELECT date_value
FROM (SELECT a.espr1+(10*b.espr1)+(100*c.espr1) AS integer_value,
dateadd("d",integer_value,dateserial([start_year], [start_month], [start_day])) as date_value
FROM (select * from 
    (
    select top 1 "0" as espr1 from MSysObjects
    union all
    select top 1 "1" as espr2 from MSysObjects
    union all
    select top 1 "2" as espr3 from MSysObjects
    union all
    select top 1 "3" as espr4 from MSysObjects
    union all
    select top 1 "4" as espr5 from MSysObjects
    union all
    select top 1 "5" as espr6 from MSysObjects
    union all
    select top 1 "6" as espr7 from MSysObjects
    union all
    select top 1 "7" as espr8 from MSysObjects
    union all
    select top 1 "8" as espr9 from MSysObjects
    union all
    select top 1 "9" as espr9 from MSysObjects
    ) as a,
    (
    select top 1 "0" as espr1 from MSysObjects
    union all
    select top 1 "1" as espr2 from MSysObjects
    union all
    select top 1 "2" as espr3 from MSysObjects
    union all
    select top 1 "3" as espr4 from MSysObjects
    union all
    select top 1 "4" as espr5 from MSysObjects
    union all
    select top 1 "5" as espr6 from MSysObjects
    union all
    select top 1 "6" as espr7 from MSysObjects
    union all
    select top 1 "7" as espr8 from MSysObjects
    union all
    select top 1 "8" as espr9 from MSysObjects
    union all
    select top 1 "9" as espr9 from MSysObjects
    ) as b,
    (
    select top 1 "0" as espr1 from MSysObjects
    union all
    select top 1 "1" as espr2 from MSysObjects
    union all
    select top 1 "2" as espr3 from MSysObjects
    union all
    select top 1 "3" as espr4 from MSysObjects
    union all
    select top 1 "4" as espr5 from MSysObjects
    union all
    select top 1 "5" as espr6 from MSysObjects
    union all
    select top 1 "6" as espr7 from MSysObjects
    union all
    select top 1 "7" as espr8 from MSysObjects
    union all
    select top 1 "8" as espr9 from MSysObjects
    union all
    select top 1 "9" as espr9 from MSysObjects
    ) as c   
)  as d) 
WHERE date_value 
between dateserial([start_year], [start_month], [start_day]) 
and dateserial([end_year], [end_month], [end_day]);

referenced MSysObjects just 'cause access need a table countin' at least 1 record, in a from clause - any table with at least 1 record would do.

How can I convert integer into float in Java?

// The integer I want to convert

int myInt = 100;

// Casting of integer to float

float newFloat = (float) myInt

How do I set a VB.Net ComboBox default value

You can try this:

Me.cbo1.Text = Me.Cbo1.Items(0).Tostring

How do I combine a background-image and CSS3 gradient on the same element?

I was trying to do the same thing. While background-color and background-image exist on separate layers within an object -- meaning they can co-exist -- CSS gradients seem to co-opt the background-image layer.

From what I can tell, border-image seems to have wider support than multiple backgrounds, so maybe that's an alternative approach.

http://articles.sitepoint.com/article/css3-border-images

UPDATE: A bit more research. Seems Petra Gregorova has something working here --> http://petragregorova.com/demos/css-gradient-and-bg-image-final.html

Is there a PowerShell "string does not contain" cmdlet or syntax?

You can use the -notmatch operator to get the lines that don't have the characters you are interested in.

     Get-Content $FileName | foreach-object { 
     if ($_ -notmatch $arrayofStringsNotInterestedIn) { $) }

Send email by using codeigniter library via localhost

I had the same problem and I solved by using the postcast server. You can install it locally and use it.

OS X Terminal shortcut: Jump to beginning/end of line

fn + shift + leftArrow = goto beginning of line
fn + shift + rightArrow = goto end of line

these work for me

How to make a 3D scatter plot in Python?

Use the following code it worked for me:

# Create the figure
fig = plt.figure()
ax = fig.add_subplot(111, projection='3d')

# Generate the values
x_vals = X_iso[:, 0:1]
y_vals = X_iso[:, 1:2]
z_vals = X_iso[:, 2:3]

# Plot the values
ax.scatter(x_vals, y_vals, z_vals, c = 'b', marker='o')
ax.set_xlabel('X-axis')
ax.set_ylabel('Y-axis')
ax.set_zlabel('Z-axis')

plt.show()

while X_iso is my 3-D array and for X_vals, Y_vals, Z_vals I copied/used 1 column/axis from that array and assigned to those variables/arrays respectively.

Node Express sending image files as API response

There is an api in Express.

res.sendFile

app.get('/report/:chart_id/:user_id', function (req, res) {
    // res.sendFile(filepath);
});

http://expressjs.com/en/api.html#res.sendFile

Bootstrap: align input with button

Use .form-inline = This will left-align labels and inline-block controls for a compact layout

Example: http://jsfiddle.net/hSuy4/292/

<div class="form-inline">
<input type="text">
<input type="button" class="btn" value="submit">
</div>

.form-horizontal = Right align labels and float them to the left to make them appear on the same line as controls which is better for 2 column form layout.

(e.g. 
Label 1: [textbox]
Label 2: [textbox]
     : [button]
)

Examples: http://twitter.github.io/bootstrap/base-css.html#forms

What is the format for the PostgreSQL connection string / URL?

The following worked for me

const conString = "postgres://YourUserName:YourPassword@YourHostname:5432/YourDatabaseName";

Where is Python's sys.path initialized from?

Python really tries hard to intelligently set sys.path. How it is set can get really complicated. The following guide is a watered-down, somewhat-incomplete, somewhat-wrong, but hopefully-useful guide for the rank-and-file python programmer of what happens when python figures out what to use as the initial values of sys.path, sys.executable, sys.exec_prefix, and sys.prefix on a normal python installation.

First, python does its level best to figure out its actual physical location on the filesystem based on what the operating system tells it. If the OS just says "python" is running, it finds itself in $PATH. It resolves any symbolic links. Once it has done this, the path of the executable that it finds is used as the value for sys.executable, no ifs, ands, or buts.

Next, it determines the initial values for sys.exec_prefix and sys.prefix.

If there is a file called pyvenv.cfg in the same directory as sys.executable or one directory up, python looks at it. Different OSes do different things with this file.

One of the values in this config file that python looks for is the configuration option home = <DIRECTORY>. Python will use this directory instead of the directory containing sys.executable when it dynamically sets the initial value of sys.prefix later. If the applocal = true setting appears in the pyvenv.cfg file on Windows, but not the home = <DIRECTORY> setting, then sys.prefix will be set to the directory containing sys.executable.

Next, the PYTHONHOME environment variable is examined. On Linux and Mac, sys.prefix and sys.exec_prefix are set to the PYTHONHOME environment variable, if it exists, superseding any home = <DIRECTORY> setting in pyvenv.cfg. On Windows, sys.prefix and sys.exec_prefix is set to the PYTHONHOME environment variable, if it exists, unless a home = <DIRECTORY> setting is present in pyvenv.cfg, which is used instead.

Otherwise, these sys.prefix and sys.exec_prefix are found by walking backwards from the location of sys.executable, or the home directory given by pyvenv.cfg if any.

If the file lib/python<version>/dyn-load is found in that directory or any of its parent directories, that directory is set to be to be sys.exec_prefix on Linux or Mac. If the file lib/python<version>/os.py is is found in the directory or any of its subdirectories, that directory is set to be sys.prefix on Linux, Mac, and Windows, with sys.exec_prefix set to the same value as sys.prefix on Windows. This entire step is skipped on Windows if applocal = true is set. Either the directory of sys.executable is used or, if home is set in pyvenv.cfg, that is used instead for the initial value of sys.prefix.

If it can't find these "landmark" files or sys.prefix hasn't been found yet, then python sets sys.prefix to a "fallback" value. Linux and Mac, for example, use pre-compiled defaults as the values of sys.prefix and sys.exec_prefix. Windows waits until sys.path is fully figured out to set a fallback value for sys.prefix.

Then, (what you've all been waiting for,) python determines the initial values that are to be contained in sys.path.

  1. The directory of the script which python is executing is added to sys.path. On Windows, this is always the empty string, which tells python to use the full path where the script is located instead.
  2. The contents of PYTHONPATH environment variable, if set, is added to sys.path, unless you're on Windows and applocal is set to true in pyvenv.cfg.
  3. The zip file path, which is <prefix>/lib/python35.zip on Linux/Mac and os.path.join(os.dirname(sys.executable), "python.zip") on Windows, is added to sys.path.
  4. If on Windows and no applocal = true was set in pyvenv.cfg, then the contents of the subkeys of the registry key HK_CURRENT_USER\Software\Python\PythonCore\<DLLVersion>\PythonPath\ are added, if any.
  5. If on Windows and no applocal = true was set in pyvenv.cfg, and sys.prefix could not be found, then the core contents of the of the registry key HK_CURRENT_USER\Software\Python\PythonCore\<DLLVersion>\PythonPath\ is added, if it exists;
  6. If on Windows and no applocal = true was set in pyvenv.cfg, then the contents of the subkeys of the registry key HK_LOCAL_MACHINE\Software\Python\PythonCore\<DLLVersion>\PythonPath\ are added, if any.
  7. If on Windows and no applocal = true was set in pyvenv.cfg, and sys.prefix could not be found, then the core contents of the of the registry key HK_CURRENT_USER\Software\Python\PythonCore\<DLLVersion>\PythonPath\ is added, if it exists;
  8. If on Windows, and PYTHONPATH was not set, the prefix was not found, and no registry keys were present, then the relative compile-time value of PYTHONPATH is added; otherwise, this step is ignored.
  9. Paths in the compile-time macro PYTHONPATH are added relative to the dynamically-found sys.prefix.
  10. On Mac and Linux, the value of sys.exec_prefix is added. On Windows, the directory which was used (or would have been used) to search dynamically for sys.prefix is added.

At this stage on Windows, if no prefix was found, then python will try to determine it by searching all the directories in sys.path for the landmark files, as it tried to do with the directory of sys.executable previously, until it finds something. If it doesn't, sys.prefix is left blank.

Finally, after all this, Python loads the site module, which adds stuff yet further to sys.path:

It starts by constructing up to four directories from a head and a tail part. For the head part, it uses sys.prefix and sys.exec_prefix; empty heads are skipped. For the tail part, it uses the empty string and then lib/site-packages (on Windows) or lib/pythonX.Y/site-packages and then lib/site-python (on Unix and Macintosh). For each of the distinct head-tail combinations, it sees if it refers to an existing directory, and if so, adds it to sys.path and also inspects the newly added path for configuration files.

How to POST request using RestSharp

it is better to use json after post your resuest like below

  var clien = new RestClient("https://smple.com/");
  var request = new RestRequest("index", Method.POST);
  request.AddHeader("Sign", signinstance);    
  request.AddJsonBody(JsonConvert.SerializeObject(yourclass));
  var response = client.Execute<YourReturnclassSample>(request);
  if (response.StatusCode == System.Net.HttpStatusCode.Created)
   {
       return Ok(response.Content);
   }

linq query to return distinct field values from a list of objects

I wanted to bind a particular data to dropdown and it should be distinct. I did the following:

List<ClassDetails> classDetails;
List<string> classDetailsData = classDetails.Select(dt => dt.Data).Distinct.ToList();
ddlData.DataSource = classDetailsData;
ddlData.Databind();

See if it helps

Choosing the default value of an Enum type without having to change values

Actually an enum's default is the first element in the enum whose value is 0.

So for example:

public enum Animals
{
    Cat,
    Dog,
    Pony = 0,
}
//its value will actually be Cat not Pony unless you assign a non zero value to Cat.
Animals animal;

Running a shell script through Cygwin on Windows

The existing answers all seem to run this script in a DOS console window.

This may be acceptable, but for example means that colour codes (changing text colour) don't work but instead get printed out as they are:

there is no item "[032mGroovy[0m"

I found this solution some time ago, so I'm not sure whether mintty.exe is a standard Cygwin utility or whether you have to run the setup program to get it, but I run like this:

D:\apps\cygwin64\bin\mintty.exe -i /Cygwin-Terminal.ico  bash.exe .\myShellScript.sh

... this causes the script to run in a Cygwin BASH console instead of a Windows DOS console.

JavaScript Array splice vs slice

Another example:

[2,4,8].splice(1, 2) -> returns [4, 8], original array is [2]

[2,4,8].slice(1, 2) -> returns 4, original array is [2,4,8]

C function that counts lines in file

Here is my function

char *fileName = "input-1.txt";
countOfLinesFromFile(fileName);

void countOfLinesFromFile(char *filename){
FILE* myfile = fopen(filename, "r");
int ch, number_of_lines = 0;
do
{
    ch = fgetc(myfile);
    if(ch == '\n')
        number_of_lines++;
}
while (ch != EOF);
if(ch != '\n' && number_of_lines != 0)
    number_of_lines++;
fclose(myfile);
printf("number of lines in  %s   = %d",filename, number_of_lines);

}

JavaScript Loading Screen while page loads

You can wait until the body is ready:

_x000D_
_x000D_
function onReady(callback) {_x000D_
  var intervalId = window.setInterval(function() {_x000D_
    if (document.getElementsByTagName('body')[0] !== undefined) {_x000D_
      window.clearInterval(intervalId);_x000D_
      callback.call(this);_x000D_
    }_x000D_
  }, 1000);_x000D_
}_x000D_
_x000D_
function setVisible(selector, visible) {_x000D_
  document.querySelector(selector).style.display = visible ? 'block' : 'none';_x000D_
}_x000D_
_x000D_
onReady(function() {_x000D_
  setVisible('.page', true);_x000D_
  setVisible('#loading', false);_x000D_
});
_x000D_
body {_x000D_
  background: #FFF url("https://i.imgur.com/KheAuef.png") top left repeat-x;_x000D_
  font-family: 'Alex Brush', cursive !important;_x000D_
}_x000D_
_x000D_
.page    { display: none; padding: 0 0.5em; }_x000D_
.page h1 { font-size: 2em; line-height: 1em; margin-top: 1.1em; font-weight: bold; }_x000D_
.page p  { font-size: 1.5em; line-height: 1.275em; margin-top: 0.15em; }_x000D_
_x000D_
#loading {_x000D_
  display: block;_x000D_
  position: absolute;_x000D_
  top: 0;_x000D_
  left: 0;_x000D_
  z-index: 100;_x000D_
  width: 100vw;_x000D_
  height: 100vh;_x000D_
  background-color: rgba(192, 192, 192, 0.5);_x000D_
  background-image: url("https://i.stack.imgur.com/MnyxU.gif");_x000D_
  background-repeat: no-repeat;_x000D_
  background-position: center;_x000D_
}
_x000D_
<link href="https://cdnjs.cloudflare.com/ajax/libs/meyer-reset/2.0/reset.min.css" rel="stylesheet"/>_x000D_
<link href="https://fonts.googleapis.com/css?family=Alex+Brush" rel="stylesheet">_x000D_
<div class="page">_x000D_
  <h1>The standard Lorem Ipsum passage</h1>_x000D_
  <p>Lorem ipsum dolor sit amet, consectetur adipisicing elit, sed do eiusmod tempor incididunt ut labore et dolore magna aliqua. Ut enim ad minim veniam, quis nostrud exercitation ullamco laboris nisi ut aliquip ex ea commodo consequat. Duis aute irure_x000D_
    dolor in reprehenderit in voluptate velit esse cillum dolore eu fugiat nulla pariatur. Excepteur sint occaecat cupidatat non proident, sunt in culpa qui officia deserunt mollit anim id est laborum.</p>_x000D_
</div>_x000D_
<div id="loading"></div>
_x000D_
_x000D_
_x000D_

Here is a JSFiddle that demonstrates this technique.

How to run a function when the page is loaded?

window.onload = function() { ... etc. is not a great answer.

This will likely work, but it will also break any other functions already hooking to that event. Or, if another function hooks into that event after yours, it will break yours. So, you can spend lots of hours later trying to figure out why something that was working isn't anymore.

A more robust answer here:

if(window.attachEvent) {
    window.attachEvent('onload', yourFunctionName);
} else {
    if(window.onload) {
        var curronload = window.onload;
        var newonload = function(evt) {
            curronload(evt);
            yourFunctionName(evt);
        };
        window.onload = newonload;
    } else {
        window.onload = yourFunctionName;
    }
}

Some code I have been using, I forget where I found it to give the author credit.

function my_function() {
    // whatever code I want to run after page load
}
if (window.attachEvent) {window.attachEvent('onload', my_function);}
else if (window.addEventListener) {window.addEventListener('load', my_function, false);}
else {document.addEventListener('load', my_function, false);}

Hope this helps :)

How to change Bootstrap's global default font size?

In v4 change the SASS variable:

$font-size-base: 1rem !default;

Simplest way to detect a pinch

My answer is inspired by Jeffrey's answer. Where that answer gives a more abstract solution, I try to provide more concrete steps on how to potentially implement it. This is simply a guide, one that can be implemented more elegantly. For a more detailed example check out this tutorial by MDN web docs.

HTML:

<div id="zoom_here">....</div>

JS

<script>
var dist1=0;
function start(ev) {
           if (ev.targetTouches.length == 2) {//check if two fingers touched screen
               dist1 = Math.hypot( //get rough estimate of distance between two fingers
                ev.touches[0].pageX - ev.touches[1].pageX,
                ev.touches[0].pageY - ev.touches[1].pageY);                  
           }
    
    }
    function move(ev) {
           if (ev.targetTouches.length == 2 && ev.changedTouches.length == 2) {
                 // Check if the two target touches are the same ones that started
               var dist2 = Math.hypot(//get rough estimate of new distance between fingers
                ev.touches[0].pageX - ev.touches[1].pageX,
                ev.touches[0].pageY - ev.touches[1].pageY);
                //alert(dist);
                if(dist1>dist2) {//if fingers are closer now than when they first touched screen, they are pinching
                  alert('zoom out');
                }
                if(dist1<dist2) {//if fingers are further apart than when they first touched the screen, they are making the zoomin gesture
                   alert('zoom in');
                }
           }
           
    }
        document.getElementById ('zoom_here').addEventListener ('touchstart', start, false);
        document.getElementById('zoom_here').addEventListener('touchmove', move, false);
</script>

How to make space between LinearLayout children?

You just need to wrap items with linear layouts which have layout_weight. To have items horizontally separated, use this

<LinearLayout
    ...
    ...
  <LinearLayout
      android:layout_width="0dp"
      android:layout_height="wrap_content"
      android:layout_weight="1"
      android:gravity="center">

      // your item

  </LinearLayout>
</LinearLayout>

Get lengths of a list in a jinja2 template

Alex' comment looks good but I was still confused with using range. The following worked for me while working on a for condition using length within range.

{% for i in range(0,(nums['list_users_response']['list_users_result']['users'])| length) %}
<li>    {{ nums['list_users_response']['list_users_result']['users'][i]['user_name'] }} </li>
{% endfor %}

Java - Writing strings to a CSV file

I think this is a simple code in java which will show the string value in CSV after compile this code.

public class CsvWriter {

    public static void main(String args[]) {
        // File input path
        System.out.println("Starting....");
        File file = new File("/home/Desktop/test/output.csv");
        try {
            FileWriter output = new FileWriter(file);
            CSVWriter write = new CSVWriter(output);

            // Header column value
            String[] header = { "ID", "Name", "Address", "Phone Number" };
            write.writeNext(header);
            // Value
            String[] data1 = { "1", "First Name", "Address1", "12345" };
            write.writeNext(data1);
            String[] data2 = { "2", "Second Name", "Address2", "123456" };
            write.writeNext(data2);
            String[] data3 = { "3", "Third Name", "Address3", "1234567" };
            write.writeNext(data3);
            write.close();
        } catch (Exception e) {
            // TODO: handle exception
            e.printStackTrace();

        }

        System.out.println("End.");

    }
}

Incrementing a variable inside a Bash loop

Using the following 1 line command for changing many files name in linux using phrase specificity:

find -type f -name '*.jpg' | rename 's/holiday/honeymoon/'

For all files with the extension ".jpg", if they contain the string "holiday", replace it with "honeymoon". For instance, this command would rename the file "ourholiday001.jpg" to "ourhoneymoon001.jpg".

This example also illustrates how to use the find command to send a list of files (-type f) with the extension .jpg (-name '*.jpg') to rename via a pipe (|). rename then reads its file list from standard input.

Regex: match everything but specific pattern

Not a regexp expert, but I think you could use a negative lookahead from the start, e.g. ^(?!foo).*$ shouldn't match anything starting with foo.

Ant task to run an Ant target only if a file exists?

Available and Condition

<target name="check-abc">
    <available file="abc.txt" property="abc.present"/>
</target>

<target name="do-if-abc" depends="check-abc" if="abc.present">
    ...
</target> 

How do I determine whether my calculation of pi is accurate?

You could use multiple approaches and see if they converge to the same answer. Or grab some from the 'net. The Chudnovsky algorithm is usually used as a very fast method of calculating pi. http://www.craig-wood.com/nick/articles/pi-chudnovsky/

setting textColor in TextView in layout/main.xml main layout file not referencing colors.xml file. (It wants a #RRGGBB instead of @color/text_color)

You should write textcolor in xml as

android:textColor="@color/text_color"

or

android:textColor="#FFFFFF"

What are the pros and cons of parquet format compared to other formats?

I think the main difference I can describe relates to record oriented vs. column oriented formats. Record oriented formats are what we're all used to -- text files, delimited formats like CSV, TSV. AVRO is slightly cooler than those because it can change schema over time, e.g. adding or removing columns from a record. Other tricks of various formats (especially including compression) involve whether a format can be split -- that is, can you read a block of records from anywhere in the dataset and still know it's schema? But here's more detail on columnar formats like Parquet.

Parquet, and other columnar formats handle a common Hadoop situation very efficiently. It is common to have tables (datasets) having many more columns than you would expect in a well-designed relational database -- a hundred or two hundred columns is not unusual. This is so because we often use Hadoop as a place to denormalize data from relational formats -- yes, you get lots of repeated values and many tables all flattened into a single one. But it becomes much easier to query since all the joins are worked out. There are other advantages such as retaining state-in-time data. So anyway it's common to have a boatload of columns in a table.

Let's say there are 132 columns, and some of them are really long text fields, each different column one following the other and use up maybe 10K per record.

While querying these tables is easy with SQL standpoint, it's common that you'll want to get some range of records based on only a few of those hundred-plus columns. For example, you might want all of the records in February and March for customers with sales > $500.

To do this in a row format the query would need to scan every record of the dataset. Read the first row, parse the record into fields (columns) and get the date and sales columns, include it in your result if it satisfies the condition. Repeat. If you have 10 years (120 months) of history, you're reading every single record just to find 2 of those months. Of course this is a great opportunity to use a partition on year and month, but even so, you're reading and parsing 10K of each record/row for those two months just to find whether the customer's sales are > $500.

In a columnar format, each column (field) of a record is stored with others of its kind, spread all over many different blocks on the disk -- columns for year together, columns for month together, columns for customer employee handbook (or other long text), and all the others that make those records so huge all in their own separate place on the disk, and of course columns for sales together. Well heck, date and months are numbers, and so are sales -- they are just a few bytes. Wouldn't it be great if we only had to read a few bytes for each record to determine which records matched our query? Columnar storage to the rescue!

Even without partitions, scanning the small fields needed to satisfy our query is super-fast -- they are all in order by record, and all the same size, so the disk seeks over much less data checking for included records. No need to read through that employee handbook and other long text fields -- just ignore them. So, by grouping columns with each other, instead of rows, you can almost always scan less data. Win!

But wait, it gets better. If your query only needed to know those values and a few more (let's say 10 of the 132 columns) and didn't care about that employee handbook column, once it had picked the right records to return, it would now only have to go back to the 10 columns it needed to render the results, ignoring the other 122 of the 132 in our dataset. Again, we skip a lot of reading.

(Note: for this reason, columnar formats are a lousy choice when doing straight transformations, for example, if you're joining all of two tables into one big(ger) result set that you're saving as a new table, the sources are going to get scanned completely anyway, so there's not a lot of benefit in read performance, and because columnar formats need to remember more about the where stuff is, they use more memory than a similar row format).

One more benefit of columnar: data is spread around. To get a single record, you can have 132 workers each read (and write) data from/to 132 different places on 132 blocks of data. Yay for parallelization!

And now for the clincher: compression algorithms work much better when it can find repeating patterns. You could compress AABBBBBBCCCCCCCCCCCCCCCC as 2A6B16C but ABCABCBCBCBCCCCCCCCCCCCCC wouldn't get as small (well, actually, in this case it would, but trust me :-) ). So once again, less reading. And writing too.

So we read a lot less data to answer common queries, it's potentially faster to read and write in parallel, and compression tends to work much better.

Columnar is great when your input side is large, and your output is a filtered subset: from big to little is great. Not as beneficial when the input and outputs are about the same.

But in our case, Impala took our old Hive queries that ran in 5, 10, 20 or 30 minutes, and finished most in a few seconds or a minute.

Hope this helps answer at least part of your question!

Set the selected index of a Dropdown using jQuery

I'm writing this answer in 2015, and for some reason (probably older versions of jQuery) none of the other answers have worked for me. I mean, they change the selected index, but it doesn't actually reflect on the actual dropdown.

Here is another way to change the index, and actually have it reflect in the dropdown:

$('#mydropdown').val('first').change();

Java :Add scroll into text area

Try adding these two lines to your code. I hope it will work. It worked for me :)

display.setLineWrap(true);
display.setWrapStyleWord(true);

Picture of output is shown below

enter image description here

What is the correct value for the disabled attribute?

  • For XHTML, <input type="text" disabled="disabled" /> is the valid markup.
  • For HTML5, <input type="text" disabled /> is valid and used by W3C on their samples.
  • In fact, both ways works on all major browsers.

BASH Syntax error near unexpected token 'done'

I have exactly the same issue as above, and took me the whole day to discover that it doesn't like my newline approach. Instead I reused the same code with semi-colon approach instead. For example my initial code using the newline (which threw the same error as yours):

Y=1
while test "$Y" -le "20"
do
        echo "Number $Y"
        Y=$[Y+1]
done

And using code with semicolon approach with worked wonder:

Y=1 ; while test "$Y" -le "20"; do echo "Number $Y"; Y=$[Y+1] ; done

I notice the same problem occurs for other commands as well using the newline approach, so I think I am gonna stick to using semicolon for my future code.

Limit characters displayed in span

You can use the CSS property max-width and use it with ch unit.
And, as this is a <span>, use a display: inline-block; (or block).

Here is an example:

<span style="
  display:inline-block;
  white-space: nowrap;
  overflow: hidden;
  text-overflow: ellipsis;
  max-width: 13ch;">
Lorem ipsum dolor sit amet
</span>

Which outputs:

Lorem ipsum...

_x000D_
_x000D_
<span style="_x000D_
  display:inline-block;_x000D_
  white-space: nowrap;_x000D_
  overflow: hidden;_x000D_
  text-overflow: ellipsis;_x000D_
  max-width: 13ch;">_x000D_
Lorem ipsum dolor sit amet_x000D_
</span>
_x000D_
_x000D_
_x000D_

How to select the first row of each group?

Window functions:

Something like this should do the trick:

import org.apache.spark.sql.functions.{row_number, max, broadcast}
import org.apache.spark.sql.expressions.Window

val df = sc.parallelize(Seq(
  (0,"cat26",30.9), (0,"cat13",22.1), (0,"cat95",19.6), (0,"cat105",1.3),
  (1,"cat67",28.5), (1,"cat4",26.8), (1,"cat13",12.6), (1,"cat23",5.3),
  (2,"cat56",39.6), (2,"cat40",29.7), (2,"cat187",27.9), (2,"cat68",9.8),
  (3,"cat8",35.6))).toDF("Hour", "Category", "TotalValue")

val w = Window.partitionBy($"hour").orderBy($"TotalValue".desc)

val dfTop = df.withColumn("rn", row_number.over(w)).where($"rn" === 1).drop("rn")

dfTop.show
// +----+--------+----------+
// |Hour|Category|TotalValue|
// +----+--------+----------+
// |   0|   cat26|      30.9|
// |   1|   cat67|      28.5|
// |   2|   cat56|      39.6|
// |   3|    cat8|      35.6|
// +----+--------+----------+

This method will be inefficient in case of significant data skew.

Plain SQL aggregation followed by join:

Alternatively you can join with aggregated data frame:

val dfMax = df.groupBy($"hour".as("max_hour")).agg(max($"TotalValue").as("max_value"))

val dfTopByJoin = df.join(broadcast(dfMax),
    ($"hour" === $"max_hour") && ($"TotalValue" === $"max_value"))
  .drop("max_hour")
  .drop("max_value")

dfTopByJoin.show

// +----+--------+----------+
// |Hour|Category|TotalValue|
// +----+--------+----------+
// |   0|   cat26|      30.9|
// |   1|   cat67|      28.5|
// |   2|   cat56|      39.6|
// |   3|    cat8|      35.6|
// +----+--------+----------+

It will keep duplicate values (if there is more than one category per hour with the same total value). You can remove these as follows:

dfTopByJoin
  .groupBy($"hour")
  .agg(
    first("category").alias("category"),
    first("TotalValue").alias("TotalValue"))

Using ordering over structs:

Neat, although not very well tested, trick which doesn't require joins or window functions:

val dfTop = df.select($"Hour", struct($"TotalValue", $"Category").alias("vs"))
  .groupBy($"hour")
  .agg(max("vs").alias("vs"))
  .select($"Hour", $"vs.Category", $"vs.TotalValue")

dfTop.show
// +----+--------+----------+
// |Hour|Category|TotalValue|
// +----+--------+----------+
// |   0|   cat26|      30.9|
// |   1|   cat67|      28.5|
// |   2|   cat56|      39.6|
// |   3|    cat8|      35.6|
// +----+--------+----------+

With DataSet API (Spark 1.6+, 2.0+):

Spark 1.6:

case class Record(Hour: Integer, Category: String, TotalValue: Double)

df.as[Record]
  .groupBy($"hour")
  .reduce((x, y) => if (x.TotalValue > y.TotalValue) x else y)
  .show

// +---+--------------+
// | _1|            _2|
// +---+--------------+
// |[0]|[0,cat26,30.9]|
// |[1]|[1,cat67,28.5]|
// |[2]|[2,cat56,39.6]|
// |[3]| [3,cat8,35.6]|
// +---+--------------+

Spark 2.0 or later:

df.as[Record]
  .groupByKey(_.Hour)
  .reduceGroups((x, y) => if (x.TotalValue > y.TotalValue) x else y)

The last two methods can leverage map side combine and don't require full shuffle so most of the time should exhibit a better performance compared to window functions and joins. These cane be also used with Structured Streaming in completed output mode.

Don't use:

df.orderBy(...).groupBy(...).agg(first(...), ...)

It may seem to work (especially in the local mode) but it is unreliable (see SPARK-16207, credits to Tzach Zohar for linking relevant JIRA issue, and SPARK-30335).

The same note applies to

df.orderBy(...).dropDuplicates(...)

which internally uses equivalent execution plan.

How do I programmatically "restart" an Android app?

The application I'm working on has to give the user the possibility to choose which fragments to display (fragments are dynamically changed at run-time). The best solution for me was to restart completely the application.

So I tried plenty of solutions and none of them has worked for me, but this:

final Intent mStartActivity = new Intent(SettingsActivity.this, Splash.class);
final int mPendingIntentId = 123456;
final PendingIntent mPendingIntent = PendingIntent.getActivity(SettingsActivity.this, mPendingIntentId, mStartActivity,
                    PendingIntent.FLAG_CANCEL_CURRENT);
final AlarmManager mgr = (AlarmManager) SettingsActivity.this.getSystemService(Context.ALARM_SERVICE);
mgr.set(AlarmManager.RTC, System.currentTimeMillis() + 100, mPendingIntent);
this.finishAffinity(); //notice here
Runtime.getRuntime().exit(0); //notice here

Hoping that is going to help someone else!

Image is not showing in browser?

Your path should be like this : "http://websitedomain//folderpath/66.jpg">

<img  src="http://websitedomain/folderpath/66.jpg" width="400" height="400" ></img>

Datetime format Issue: String was not recognized as a valid DateTime

You may use this type format (get formatted data from sql server)


FORMAT(convert(datetime,'16/04/2018 10:52:20',103),'dd/MM/yyyy HH:mm:ss', 'en-us')


CONVERT(VARCHAR,convert(datetime,'16/04/2018 10:52:20',103), 120)

Unique constraint on multiple columns

By using the constraint definition on table creation, you can specify one or multiple constraints that span multiple columns. The syntax, simplified from technet's documentation, is in the form of:

CONSTRAINT constraint_name UNIQUE [ CLUSTERED | NONCLUSTERED ] 
(
    column [ ASC | DESC ] [ ,...n ]
)

Therefore, the resuting table definition would be:

CREATE TABLE [dbo].[user](
    [userID] [int] IDENTITY(1,1) NOT NULL,
    [fcode] [int] NULL,
    [scode] [int] NULL,
    [dcode] [int] NULL,
    [name] [nvarchar](50) NULL,
    [address] [nvarchar](50) NULL,
    CONSTRAINT [PK_user_1] PRIMARY KEY CLUSTERED 
    (
        [userID] ASC
    ),
    CONSTRAINT [UQ_codes] UNIQUE NONCLUSTERED
    (
        [fcode], [scode], [dcode]
    )
) ON [PRIMARY]

Resource leak: 'in' is never closed

The Scanner should be closed. It is a good practice to close Readers, Streams...and this kind of objects to free up resources and aovid memory leaks; and doing so in a finally block to make sure that they are closed up even if an exception occurs while handling those objects.

Javascript receipt printing using POS Printer

I have recently implemented the receipt printing simply by pressing a button on a web page, without having to enter the printer options. I have done it using EPSON javascript SDK for ePOS. I have test it on EPSON TM-m30 receipt printer.

Here is the sample code.

var printer = null;
var ePosDev = null;

function InitMyPrinter() {
    console.log("Init Printer");

    var printerPort = 8008;
    var printerAddress = "192.168.198.168";
    if (isSSL) {
        printerPort = 8043;
    }
    ePosDev = new epson.ePOSDevice();
    ePosDev.connect(printerAddress, printerPort, cbConnect);
}

//Printing
function cbConnect(data) {
    if (data == 'OK' || data == 'SSL_CONNECT_OK') {
        ePosDev.createDevice('local_printer', ePosDev.DEVICE_TYPE_PRINTER,
            {'crypto': false, 'buffer': false}, cbCreateDevice_printer);
    } else {
        console.log(data);
    }
}

function cbCreateDevice_printer(devobj, retcode) {
    if (retcode == 'OK') {
        printer = devobj;
        printer.timeout = 60000;
        printer.onreceive = function (res) { //alert(res.success);
            console.log("Printer Object Created");

        };
        printer.oncoveropen = function () { //alert('coveropen');
            console.log("Printer Cover Open");

        };
    } else {
        console.log(retcode);
        isRegPrintConnected = false;
    }
}

function print(salePrintObj) {
    debugger;
    if (isRegPrintConnected == false
        || printer == null) {
        return;
    }
    console.log("Printing Started");


    printer.addLayout(printer.LAYOUT_RECEIPT, 800, 0, 0, 0, 35, 0);
    printer.addTextAlign(printer.ALIGN_CENTER);
    printer.addTextSmooth(true);
    printer.addText('\n');
    printer.addText('\n');

    printer.addTextDouble(true, true);
    printer.addText(CompanyName + '\n');

    printer.addTextDouble(false, false);
    printer.addText(CompanyHeader + '\n');
    printer.addText('\n');

    printer.addTextAlign(printer.ALIGN_LEFT);
    printer.addText('DATE: ' + currentDate + '\t\t');

    printer.addTextAlign(printer.ALIGN_RIGHT);
    printer.addText('TIME: ' + currentTime + '\n');

    printer.addTextAlign(printer.ALIGN_LEFT);

    printer.addTextAlign(printer.ALIGN_RIGHT);
    printer.addText('REGISTER: ' + RegisterName + '\n');
    printer.addTextAlign(printer.ALIGN_LEFT);
    printer.addText('SALE # ' + SaleNumber + '\n');

    printer.addTextAlign(printer.ALIGN_CENTER);
    printer.addTextStyle(false, false, true, printer.COLOR_1);
    printer.addTextStyle(false, false, false, printer.COLOR_1);
    printer.addTextDouble(false, true);
    printer.addText('* SALE RECEIPT *\n');
    printer.addTextDouble(false, false);
....
....
....

}

Android Studio error: "Environment variable does not point to a valid JVM installation"

I solved this problem by making sure that the value of JAVA_HOME was the folder location in English

C:\Program Files\Java\jdk1.8.0_31

rather than the folder location that one can see/explorer browse in my Windows7 - Portuguese installation

C:\Programas\Java\jdk1.8.0_31

How to pad a string with leading zeros in Python 3

Make use of the zfill() helper method to left-pad any string, integer or float with zeros; it's valid for both Python 2.x and Python 3.x.

Sample usage:

print str(1).zfill(3);
# Expected output: 001

Description:

When applied to a value, zfill() returns a value left-padded with zeros when the length of the initial string value less than that of the applied width value, otherwise, the initial string value as is.

Syntax:

str(string).zfill(width)
# Where string represents a string, an integer or a float, and
# width, the desired length to left-pad.

Zooming MKMapView to fit annotation pins?

For iOS 7 and above (Referring MKMapView.h) :

// Position the map such that the provided array of annotations are all visible to the fullest extent possible.          

- (void)showAnnotations:(NSArray *)annotations animated:(BOOL)animated NS_AVAILABLE(10_9, 7_0);

remark from – Abhishek Bedi

You just call:

 [yourMapView showAnnotations:@[yourAnnotation] animated:YES];

CSS Custom Dropdown Select that works across all browsers IE7+ FF Webkit

<select class="dropdownmenu" name="drop-down">
    <option class="dropdownmenu_list1" value="select-option">Choose ...</option>
    <option class="dropdownmenu_list2" value="Topic 1">Option 1</option>
    <option class="dropdownmenu_list3" value="Topic 2">Option 2</option>
</select>

This works best in Firefox. Too bad that Chrome and Safari do not support this rather easy CSS styling.

Java dynamic array sizes?

In Java Array Sizes are always of Fixed Length But there is way in which you can Dynamically increase the Size of the Array at Runtime Itself

This is the most "used" as well as preferred way to do it-

    int temp[]=new int[stck.length+1];
    for(int i=0;i<stck.length;i++)temp[i]=stck[i];
    stck=temp;

In the above code we are initializing a new temp[] array, and further using a for loop to initialize the contents of the temp with the contents of the original array ie. stck[]. And then again copying it back to the original one, giving us a new array of new SIZE.

No doubt it generates a CPU Overhead due to reinitializing an array using for loop repeatedly. But you can still use and implement it in your code. For the best practice use "Linked List" instead of Array, if you want the data to be stored dynamically in the memory, of variable length.

Here's a Real-Time Example based on Dynamic Stacks to INCREASE ARRAY SIZE at Run-Time

File-name: DStack.java

public class DStack {
private int stck[];
int tos;

void Init_Stck(int size) {
    stck=new int[size];
    tos=-1;
}
int Change_Stck(int size){
    return stck[size];
}

public void push(int item){
    if(tos==stck.length-1){
        int temp[]=new int[stck.length+1];
        for(int i=0;i<stck.length;i++)temp[i]=stck[i];
        stck=temp;
        stck[++tos]=item;
    }
    else
        stck[++tos]=item;
}
public int pop(){
    if(tos<0){
        System.out.println("Stack Underflow");
        return 0;
    }
    else return stck[tos--];
}

public void display(){
    for(int x=0;x<stck.length;x++){
        System.out.print(stck[x]+" ");
    }
    System.out.println();
}

}

File-name: Exec.java
(with the main class)

import java.util.*;
public class Exec {

private static Scanner in;

public static void main(String[] args) {
    in = new Scanner(System.in);
    int option,item,i=1;
    DStack obj=new DStack();
    obj.Init_Stck(1);
    do{
        System.out.println();
        System.out.println("--MENU--");
        System.out.println("1. Push a Value in The Stack");
        System.out.println("2. Pop a Value from the Stack");
        System.out.println("3. Display Stack");
        System.out.println("4. Exit");
        option=in.nextInt();
        switch(option){
        case 1:
            System.out.println("Enter the Value to be Pushed");
            item=in.nextInt();
            obj.push(item);
            break;
        case 2:
            System.out.println("Popped Item: "+obj.pop());
            obj.Change_Stck(obj.tos);
            break;
        case 3:
            System.out.println("Displaying...");
            obj.display();
            break;
        case 4:
            System.out.println("Exiting...");
            i=0;
            break;
        default:
            System.out.println("Enter a Valid Value");

        }
    }while(i==1);

}

}

Hope this solves your query.

"Could not find the main class" error when running jar exported by Eclipse

Verify that you can start your application like that:

java -cp myjarfile.jar snake.Controller

I just read when I double click on it - this sounds like a configuration issue with your operating system. You're double-clicking the file on a windows explorer window? Try to run it from a console/terminal with the command

java -jar myjarfile.jar

Further Reading


The manifest has to end with a new line. Please check your file, a missing new line will cause trouble.

Set adb vendor keys

I tried every method listed here and in Android adb devices unauthorized

What eventually worked for me was the option just below USB Debugging 'Revoke auths'

How to convert color code into media.brush?

Sorry to be so late to the party! I came across a similar issue, in WinRT. I'm not sure whether you're using WPF or WinRT, but they do differ in some ways (some better than others). Hopefully this will help people across the board, whichever situation they're in.

You could always use the code from the converter class I created to re-use and do in your C# code-behind, or wherever you're using it, to be honest:

I made it with the intention that a 6-digit (RGB), or an 8-digit (ARGB) Hex value could be used either way.

So I created a converter class:

public class StringToSolidColorBrushConverter : IValueConverter
{
    public object Convert(object value, Type targetType, object parameter, string language)
    {
        var hexString = (value as string).Replace("#", "");

        if (string.IsNullOrWhiteSpace(hexString)) throw new FormatException();
        if (hexString.Length != 6 || hexString.Length != 8) throw new FormatException();

        try
        {
            var a = hexString.Length == 8 ? hexString.Substring(0, 2) : "255";
            var r = hexString.Length == 8 ? hexString.Substring(2, 2) : hexString.Substring(0, 2);
            var g = hexString.Length == 8 ? hexString.Substring(4, 2) : hexString.Substring(2, 2);
            var b = hexString.Length == 8 ? hexString.Substring(6, 2) : hexString.Substring(4, 2);

            return new SolidColorBrush(ColorHelper.FromArgb(
                byte.Parse(a, System.Globalization.NumberStyles.HexNumber),
                byte.Parse(r, System.Globalization.NumberStyles.HexNumber),
                byte.Parse(g, System.Globalization.NumberStyles.HexNumber),
                byte.Parse(b, System.Globalization.NumberStyles.HexNumber)));
        }
        catch
        {
            throw new FormatException();
        }
    }

    public object ConvertBack(object value, Type targetType, object parameter, string language)
    {
        throw new NotImplementedException();
    }
}

Added it into my App.xaml:

<ResourceDictionary>
    ...
    <converters:StringToSolidColorBrushConverter x:Key="StringToSolidColorBrushConverter" />
    ...
</ResourceDictionary>

And used it in my View's Xaml:

<Grid>
    <Rectangle Fill="{Binding RectangleColour,
               Converter={StaticResource StringToSolidColorBrushConverter}}"
               Height="20" Width="20" />
</Grid>

Works a charm!

Side note... Unfortunately, WinRT hasn't got the System.Windows.Media.BrushConverter that H.B. suggested; so I needed another way, otherwise I would have made a VM property that returned a SolidColorBrush (or similar) from the RectangleColour string property.

Colorized grep -- viewing the entire file with highlighted matches

It might seem like a dirty hack.

grep "^\|highlight1\|highlight2\|highlight3" filename

Which means - match the beginning of the line(^) or highlight1 or highlight2 or highlight3. As a result, you will get highlighted all highlight* pattern matches, even in the same line.

Get JSON Data from URL Using Android?

    BufferedReader reader = new BufferedReader(new InputStreamReader(response.getEntity().getContent(), "UTF-8"));
String sResponse;
StringBuilder s = new StringBuilder();

while ((sResponse = reader.readLine()) != null) {
    s = s.append(sResponse);
}
Gson gson = new Gson();

JSONObject jsonObject = new JSONObject(s.toString());
String link = jsonObject.getString("Result");

How to access Session variables and set them in javascript?

You can't access Session directly in JavaScript.

You can make a hidden field and pass it to your page and then use JavaScript to retrieve the object via document.getElementById

How to enable zoom controls and pinch zoom in a WebView?

Check if you don't have a ScrollView wrapping your Webview.

In my case that was the problem. It seems ScrollView gets in the way of the pinch gesture.

To fix it, just take your Webview outside the ScrollView.

How to replace a set of tokens in a Java String?

String.format("Hello %s Please find attached %s which is due on %s", name, invoice, date)

Tkinter scrollbar for frame

We can add scroll bar even without using Canvas. I have read it in many other post we can't add vertical scroll bar in frame directly etc etc. But after doing many experiment found out way to add vertical as well as horizontal scroll bar :). Please find below code which is used to create scroll bar in treeView and frame.

f = Tkinter.Frame(self.master,width=3)
f.grid(row=2, column=0, columnspan=8, rowspan=10, pady=30, padx=30)
f.config(width=5)
self.tree = ttk.Treeview(f, selectmode="extended")
scbHDirSel =tk.Scrollbar(f, orient=Tkinter.HORIZONTAL, command=self.tree.xview)
scbVDirSel =tk.Scrollbar(f, orient=Tkinter.VERTICAL, command=self.tree.yview)
self.tree.configure(yscrollcommand=scbVDirSel.set, xscrollcommand=scbHDirSel.set)           
self.tree["columns"] = (self.columnListOutput)
self.tree.column("#0", width=40)
self.tree.heading("#0", text='SrNo', anchor='w')
self.tree.grid(row=2, column=0, sticky=Tkinter.NSEW,in_=f, columnspan=10, rowspan=10)
scbVDirSel.grid(row=2, column=10, rowspan=10, sticky=Tkinter.NS, in_=f)
scbHDirSel.grid(row=14, column=0, rowspan=2, sticky=Tkinter.EW,in_=f)
f.rowconfigure(0, weight=1)
f.columnconfigure(0, weight=1)

Does 'position: absolute' conflict with Flexbox?

You have to give width:100% to parent to center the text.

_x000D_
_x000D_
 .parent {_x000D_
   display: flex;_x000D_
   justify-content: center;_x000D_
   position: absolute;_x000D_
   width:100%_x000D_
 }
_x000D_
<div class="parent">_x000D_
  <div class="child">text</div>_x000D_
</div>
_x000D_
_x000D_
_x000D_

If you also need to centre align vertically, give height:100% and align-itens: center

.parent {
   display: flex;
   justify-content: center;
   align-items: center;
   position: absolute;
   width:100%;
   height: 100%;
 }

Angularjs autocomplete from $http

You need to write a controller with ng-change function in scope. In ng-change callback you do a call to server and update completions. Here is a stub (without $http as this is a plunk):

HTML

<!doctype html>
<html ng-app="plunker">
    <head>
        <script src="http://ajax.googleapis.com/ajax/libs/angularjs/1.0.5/angular.js"></script>
        <script src="http://angular-ui.github.io/bootstrap/ui-bootstrap-tpls-0.4.0.js"></script>
        <script src="example.js"></script>
        <link href="//netdna.bootstrapcdn.com/twitter-bootstrap/2.3.1/css/bootstrap-combined.min.css" rel="stylesheet">
    </head>
    <body>
        <div class='container-fluid' ng-controller="TypeaheadCtrl">
            <pre>Model: {{selected| json}}</pre>
            <pre>{{states}}</pre>
            <input type="text" ng-change="onedit()" ng-model="selected" typeahead="state for state in states | filter:$viewValue">
        </div>
    </body>
</html>

JS

angular.module('plunker', ['ui.bootstrap']);

function TypeaheadCtrl($scope) {
  $scope.selected = undefined;
  $scope.states = [];

  $scope.onedit = function(){
    $scope.states = [];

    for(var i = 0; i < Math.floor((Math.random()*10)+1); i++){
      var value = "";

      for(var j = 0; j < i; j++){
        value += j;
      }
      $scope.states.push(value);
    }
  }
}

Can't clone a github repo on Linux via HTTPS

You can manual disable ssl verfiy, and try again. :)

git config --global http.sslverify false

How to check a string for a special character?

You can use string.punctuation and any function like this

import string
invalidChars = set(string.punctuation.replace("_", ""))
if any(char in invalidChars for char in word):
    print "Invalid"
else:
    print "Valid"

With this line

invalidChars = set(string.punctuation.replace("_", ""))

we are preparing a list of punctuation characters which are not allowed. As you want _ to be allowed, we are removing _ from the list and preparing new set as invalidChars. Because lookups are faster in sets.

any function will return True if atleast one of the characters is in invalidChars.

Edit: As asked in the comments, this is the regular expression solution. Regular expression taken from https://stackoverflow.com/a/336220/1903116

word = "Welcome"
import re
print "Valid" if re.match("^[a-zA-Z0-9_]*$", word) else "Invalid"

Does file_get_contents() have a timeout setting?

Yes! By passing a stream context in the third parameter:

Here with a timeout of 1s:

file_get_contents("https://abcedef.com", 0, stream_context_create(["http"=>["timeout"=>1]]));

Source in comment section of https://www.php.net/manual/en/function.file-get-contents.php

HTTP context options:

method
header
user_agent
content
request_fulluri
follow_location
max_redirects
protocol_version
timeout

Other contexts: https://www.php.net/manual/en/context.php

Schema validation failed with the following errors: Data path ".builders['app-shell']" should have required property 'class'

What i did was to uninstall and install the "^0.13.0". I confirm/ support this last answer. It worked for me as well. I had uninstall version "^0.800.0" and installed the "^0.13.0". rebuild your project it will work fine.

How to deal with floating point number precision in JavaScript?

The result you've got is correct and fairly consistent across floating point implementations in different languages, processors and operating systems - the only thing that changes is the level of the inaccuracy when the float is actually a double (or higher).

0.1 in binary floating points is like 1/3 in decimal (i.e. 0.3333333333333... forever), there's just no accurate way to handle it.

If you're dealing with floats always expect small rounding errors, so you'll also always have to round the displayed result to something sensible. In return you get very very fast and powerful arithmetic because all the computations are in the native binary of the processor.

Most of the time the solution is not to switch to fixed-point arithmetic, mainly because it's much slower and 99% of the time you just don't need the accuracy. If you're dealing with stuff that does need that level of accuracy (for instance financial transactions) Javascript probably isn't the best tool to use anyway (as you've want to enforce the fixed-point types a static language is probably better).

You're looking for the elegant solution then I'm afraid this is it: floats are quick but have small rounding errors - always round to something sensible when displaying their results.

How can I get column names from a table in SQL Server?

By using this query you get the answer:

select Column_name 
from Information_schema.columns 
where Table_name like 'table name'

multi line comment vb.net in Visual studio 2010

Highlight block of text, then:

Comment Block: Ctrl + K + C

Uncomment Block: Ctrl + K + U

Tested in Visual Studio 2012

SQL Server : trigger how to read value for Insert, Update, Delete

There is no updated dynamic table. There is just inserted and deleted. On an UPDATE command, the old data is stored in the deleted dynamic table, and the new values are stored in the inserted dynamic table.

Think of an UPDATE as a DELETE/INSERT combination.

ASP.NET MVC: What is the correct way to redirect to pages/actions in MVC?

1) When the user logs out (Forms signout in Action) I want to redirect to a login page.

public ActionResult Logout() {
    //log out the user
    return RedirectToAction("Login");
}

2) In a Controller or base Controller event eg Initialze, I want to redirect to another page (AbsoluteRootUrl + Controller + Action)

Why would you want to redirect from a controller init?

the routing engine automatically handles requests that come in, if you mean you want to redirect from the index action on a controller simply do:

public ActionResult Index() {
    return RedirectToAction("whateverAction", "whateverController");
}

How to change the datetime format in pandas

The below code worked for me instead of the previous one - try it out !

df['DOB']=pd.to_datetime(df['DOB'].astype(str), format='%m/%d/%Y')

Initializing select with AngularJS and ng-repeat

For the select tag, angular provides the ng-options directive. It gives you the specific framework to set up options and set a default. Here is the updated fiddle using ng-options that works as expected: http://jsfiddle.net/FxM3B/4/

Updated HTML (code stays the same)

<body ng-app ng-controller="AppCtrl">
<div>Operator is: {{filterCondition.operator}}</div>
<select ng-model="filterCondition.operator" ng-options="operator.value as operator.displayName for operator in operators">
</select>
</body>

jQuery delete all table rows except first

I think this is more readable given the intent:

$('someTableSelector').children( 'tr:not(:first)' ).remove();

Using children also takes care of the case where the first row contains a table by limiting the depth of the search.

If you had an TBODY element, you can do this:

$("someTableSelector > tbody:last").children().remove();

If you have THEAD or TFOOT elements you'll need to do something different.

Conditional statement in a one line lambda function in python?

The right way to do this is simple:

def rate(T):
    if (T > 200):
        return 200*exp(-T)
    else:
        return 400*exp(-T)

There is absolutely no advantage to using lambda here. The only thing lambda is good for is allowing you to create anonymous functions and use them in an expression (as opposed to a statement). If you immediately assign the lambda to a variable, it's no longer anonymous, and it's used in a statement, so you're just making your code less readable for no reason.

The rate function defined this way can be stored in an array, passed around, called, etc. in exactly the same way a lambda function could. It'll be exactly the same (except a bit easier to debug, introspect, etc.).


From a comment:

Well the function needed to fit in one line, which i didn't think you could do with a named function?

I can't imagine any good reason why the function would ever need to fit in one line. But sure, you can do that with a named function. Try this in your interpreter:

>>> def foo(x): return x + 1

Also these functions are stored as strings which are then evaluated using "eval" which i wasn't sure how to do with regular functions.

Again, while it's hard to be 100% sure without any clue as to why why you're doing this, I'm at least 99% sure that you have no reason or a bad reason for this. Almost any time you think you want to pass Python functions around as strings and call eval so you can use them, you actually just want to pass Python functions around as functions and use them as functions.

But on the off chance that this really is what you need here: Just use exec instead of eval.

You didn't mention which version of Python you're using. In 3.x, the exec function has the exact same signature as the eval function:

exec(my_function_string, my_globals, my_locals)

In 2.7, exec is a statement, not a function—but you can still write it in the same syntax as in 3.x (as long as you don't try to assign the return value to anything) and it works.

In earlier 2.x (before 2.6, I think?) you have to do it like this instead:

exec my_function_string in my_globals, my_locals

How does #include <bits/stdc++.h> work in C++?

That header file is not part of the C++ standard, is therefore non-portable, and should be avoided.

Moreover, even if there were some catch-all header in the standard, you would want to avoid it in lieu of specific headers, since the compiler has to actually read in and parse every included header (including recursively included headers) every single time that translation unit is compiled.

How do I count unique visitors to my site?

I have edited the "Best answer" code, though I found a useful thing that was missing. This is will also track the ip of a user if they are using a Proxy or simply if the server has nginx installed as a proxy reverser.

I added this code to his script at the top of the function:

function getRealIpAddr()
{
    if (!empty($_SERVER['HTTP_CLIENT_IP']))   //check ip from share internet
    {
      $ip=$_SERVER['HTTP_CLIENT_IP'];
    }
    elseif (!empty($_SERVER['HTTP_X_FORWARDED_FOR']))   //to check ip is pass from proxy
    {
      $ip=$_SERVER['HTTP_X_FORWARDED_FOR'];
    }
    else
    {
      $ip=$_SERVER['REMOTE_ADDR'];
    }
    return $ip;
}
$adresseip = getRealIpAddr();

Afther that I edited his code.

Find the line that says the following:

// get the user name if it is logged, or the visitors IP (and add the identifier)

    $uvon = isset($_SESSION['nume']) ? $_SESSION['nume'] : $_SERVER['SERVER_ADDR']. $vst_id;

and replace it with this:

$uvon = isset($_SESSION['nume']) ? $_SESSION['nume'] : $adresseip. $vst_id;

This will work.

Here is the full code if anything happens:

<?php

function getRealIpAddr()
{
    if (!empty($_SERVER['HTTP_CLIENT_IP']))   //check ip from share internet
    {
      $ip=$_SERVER['HTTP_CLIENT_IP'];
    }
    elseif (!empty($_SERVER['HTTP_X_FORWARDED_FOR']))   //to check ip is pass from proxy
    {
      $ip=$_SERVER['HTTP_X_FORWARDED_FOR'];
    }
    else
    {
      $ip=$_SERVER['REMOTE_ADDR'];
    }
    return $ip;
}
$adresseip = getRealIpAddr();

// Script Online Users and Visitors - http://coursesweb.net/php-mysql/
if(!isset($_SESSION)) session_start();        // start Session, if not already started

$filetxt = 'userson.txt';  // the file in which the online users /visitors are stored
$timeon = 120;             // number of secconds to keep a user online
$sep = '^^';               // characters used to separate the user name and date-time
$vst_id = '-vst-';        // an identifier to know that it is a visitor, not logged user

/*
 If you have an user registration script,
 replace $_SESSION['nume'] with the variable in which the user name is stored.
 You can get a free registration script from:  http://coursesweb.net/php-mysql/register-login-script-users-online_s2
*/

// get the user name if it is logged, or the visitors IP (and add the identifier)

    $uvon = isset($_SESSION['nume']) ? $_SESSION['nume'] : $_SERVER['SERVER_ADDR']. $vst_id;

$rgxvst = '/^([0-9\.]*)'. $vst_id. '/i';         // regexp to recognize the line with visitors
$nrvst = 0;                                       // to store the number of visitors

// sets the row with the current user /visitor that must be added in $filetxt (and current timestamp)

    $addrow[] = $uvon. $sep. time();

// check if the file from $filetxt exists and is writable

    if(is_writable($filetxt)) {
      // get into an array the lines added in $filetxt
      $ar_rows = file($filetxt, FILE_IGNORE_NEW_LINES | FILE_SKIP_EMPTY_LINES);
      $nrrows = count($ar_rows);

            // number of rows

  // if there is at least one line, parse the $ar_rows array

      if($nrrows>0) {
        for($i=0; $i<$nrrows; $i++) {
          // get each line and separate the user /visitor and the timestamp
          $ar_line = explode($sep, $ar_rows[$i]);
      // add in $addrow array the records in last $timeon seconds
          if($ar_line[0]!=$uvon && (intval($ar_line[1])+$timeon)>=time()) {
            $addrow[] = $ar_rows[$i];
          }
        }
      }
    }

$nruvon = count($addrow);                   // total online
$usron = '';                                    // to store the name of logged users
// traverse $addrow to get the number of visitors and users
for($i=0; $i<$nruvon; $i++) {
 if(preg_match($rgxvst, $addrow[$i])) $nrvst++;       // increment the visitors
 else {
   // gets and stores the user's name
   $ar_usron = explode($sep, $addrow[$i]);
   $usron .= '<br/> - <i>'. $ar_usron[0]. '</i>';
 }
}
$nrusr = $nruvon - $nrvst;              // gets the users (total - visitors)

// the HTML code with data to be displayed
$reout = '<div id="uvon"><h4>Online: '. $nruvon. '</h4>Visitors: '. $nrvst. '<br/>Users: '. $nrusr. $usron. '</div>';

// write data in $filetxt
if(!file_put_contents($filetxt, implode("\n", $addrow))) $reout = 'Error: Recording file not exists, or is not writable';

// if access from <script>, with GET 'uvon=showon', adds the string to return into a JS statement
// in this way the script can also be included in .html files
if(isset($_GET['uvon']) && $_GET['uvon']=='showon') $reout = "document.write('$reout');";

echo $reout;             // output /display the result

Haven't tested this on the Sql script yet.

Why can't I define a default constructor for a struct in .NET?

Just special-case it. If you see a numerator of 0 and a denominator of 0, pretend like it has the values you really want.

Easy way to print Perl array? (with a little formatting)

You can simply print it.

@a = qw(abc def hij);

print "@a";

You will got:

abc def hij

What is the bower (and npm) version syntax?

If there is no patch number, ~ is equivalent to appending .x to the non-tilde version. If there is a patch number, ~ allows all patch numbers >= the specified one.

~1     := 1.x
~1.2   := 1.2.x
~1.2.3 := (>=1.2.3 <1.3.0)

I don't have enough points to comment on the accepted answer, but some of the tilde information is at odds with the linked semver documentation: "angular": "~1.2" will not match 1.3, 1.4, 1.4.9. Also "angular": "~1" and "angular": "~1.0" are not equivalent. This can be verified with the npm semver calculator.

Xcode: failed to get the task for process

Just had the same problem - app was being installed OK, but won't run from Xcode with the "process launch failed: failed to get the task for process".

Turns out my development certificate expired during the night. Regenerating the certificate and the provisioning profiles solved the problem.

.htaccess not working on localhost with XAMPP

I've setup xampp for my localhost as well, I've not done anything with the files created by xampp during or after setup.

But in the '.htaccess' file, make sure you've set it to something like this. Works for me, and this should not make any difference for you.

RewriteEngine On
RewriteRule ^filename/?$ filename.html

Change .html to whatever format you're using.

Make sure your install is clean, and just make the .htaccess file. Also remember to put one .htaccess file for each directory (don't really know if you can use ONE file for all folders, but to be safe, just do this and it will always work.

How do you implement a good profanity filter?

I agree with the futility of the subject, but if you have to have a filter, check out Ning's Boxwood:

Boxwood is a PHP extension for fast replacement of multiple words in a piece of text. It supports case-sensitive and case-insensitive matching. It requires that the text it operates on be encoded as UTF-8.

Also see this blog post for more details:

With Boxwood, you can have your list of search terms be as long as you like -- the search and replace algorithm doesn't get slower with more words on the list of words to look for. It works by building a trie of all the search terms and then scans your subject text just once, walking down elements of the trie and comparing them to characters in your text. It supports US-ASCII and UTF-8, case-sensitive or insensitive matching, and has some English-centric word boundary checking logic.

Angular2 - Radio Button Binding

Here is a solution that works for me. It involves radio button binding--but not binding to business data, but instead, binding to the state of the radio button. It is probably NOT the best solution for new projects, but is appropriate for my project. My project has a ton of existing code written in a different technology which I am porting to Angular. The old code follows a pattern in which the code is very interested in examining each radio button to see if it is the selected one. The solution is a variation of the click handler solutions, some of which have already been mentioned on Stack Overflow. The value added of this solution may be:

  1. Works with the pattern of old code that I have to work with.
  2. I created a helper class to try to reduce the number of "if" statements in the click handler, and to handle any group of radio buttons.

This solution involves

  1. Using a different model for each radio button.
  2. Setting the "checked" attribute with the radio button's model.
  3. Passing the model of the clicked radio button to the helper class.
  4. The helper class makes sure the models are up-to-date.
  5. At "submit time" this allows the old code to examine the state of the radio buttons to see which one is selected by examining the models.

Example:

<input type="radio"
    [checked]="maleRadioButtonModel.selected"
    (click)="radioButtonGroupList.selectButton(maleRadioButtonModel)"

...

 <input type="radio"
    [checked]="femaleRadioButtonModel.selected"
    (click)="radioButtonGroupList.selectButton(femaleRadioButtonModel)"

...

When the user clicks a radio button, the selectButton method of the helper class gets invoked. It is passed the model for the radio button that got clicked. The helper class sets the boolean "selected" field of the passed in model to true, and sets the "selected" field of all the other radio button models to false.

During initialization the component must construct an instance of the helper class with a list of all radio button models in the group. In the example, "radioButtonGroupList" would be an instance of the helper class whose code is:

 import {UIButtonControlModel} from "./ui-button-control.model";


 export class UIRadioButtonGroupListModel {

  private readonly buttonList : UIButtonControlModel[];
  private readonly debugName : string;


  constructor(buttonList : UIButtonControlModel[], debugName : string) {

    this.buttonList = buttonList;
    this.debugName = debugName;

    if (this.buttonList == null) {
      throw new Error("null buttonList");
    }

    if (this.buttonList.length < 2) {
      throw new Error("buttonList has less than 2 elements")
    }
  }



  public selectButton(buttonToSelect : UIButtonControlModel) : void {

    let foundButton : boolean = false;
    for(let i = 0; i < this.buttonList.length; i++) {
      let oneButton : UIButtonControlModel = this.buttonList[i];
      if (oneButton === buttonToSelect) {
        oneButton.selected = true;
        foundButton = true;
      } else {
        oneButton.selected = false;
      }

    }

    if (! foundButton) {
      throw new Error("button not found in buttonList");
    }
  }
}

Flutter : Vertically center column

With Column, use:

mainAxisAlignment: MainAxisAlignment.center

It align its children(s) to center of its parent Space vertically

Difference between `constexpr` and `const`

const applies for variables, and prevents them from being modified in your code.

constexpr tells the compiler that this expression results in a compile time constant value, so it can be used in places like array lengths, assigning to const variables, etc. The link given by Oli has a lot of excellent examples.

Basically they are 2 different concepts altogether, and can (and should) be used together.

ConcurrentHashMap vs Synchronized HashMap

The short answer:

Both maps are thread-safe implementations of the Map interface. ConcurrentHashMap is implemented for higher throughput in cases where high concurrency is expected.

Brian Goetz's article on the idea behind ConcurrentHashMap is a very good read. Highly recommended.

Closure in Java 7

Here is Neal Gafter's blog one of the pioneers introducing closures in Java. His post on closures from January 28, 2007 is named A Definition of Closures On his blog there is lots of information to get you started as well as videos. An here is an excellent Google talk - Advanced Topics In Programming Languages - Closures For Java with Neal Gafter, as well.

How to update an "array of objects" with Firestore?

Here is the latest example from the Firestore documentation:

firebase.firestore.FieldValue.ArrayUnion

var washingtonRef = db.collection("cities").doc("DC");

// Atomically add a new region to the "regions" array field.
washingtonRef.update({
    regions: firebase.firestore.FieldValue.arrayUnion("greater_virginia")
});

// Atomically remove a region from the "regions" array field.
washingtonRef.update({
    regions: firebase.firestore.FieldValue.arrayRemove("east_coast")
});

mysql_config not found when installing mysqldb python interface

I fixed this problem with the following steps:

sudo apt-get install libmysqlclient-dev
sudo apt-get install python-dev
sudo python setup.py install

MaxJsonLength exception in ASP.NET MVC during JavaScriptSerializer

It appears this has been fixed in MVC4.

You can do this, which worked well for me:

public ActionResult SomeControllerAction()
{
  var jsonResult = Json(veryLargeCollection, JsonRequestBehavior.AllowGet);
  jsonResult.MaxJsonLength = int.MaxValue;
  return jsonResult;
}