Programs & Examples On #Multiple dispatch

A technique for polymorphic invocation of methods based on the types of many (or all) arguments. Compare to single-dispatch, used in common OO languages, where methods can only be polymorphic in the first argument -- the runtime resolution of a.doSomething(x, y, z) depends only on the type of a.

Python function overloading

I think a Bullet class hierarchy with the associated polymorphism is the way to go. You can effectively overload the base class constructor by using a metaclass so that calling the base class results in the creation of the appropriate subclass object. Below is some sample code to illustrate the essence of what I mean.

Updated

The code has been modified to run under both Python 2 and 3 to keep it relevant. This was done in a way that avoids the use Python's explicit metaclass syntax, which varies between the two versions.

To accomplish that objective, a BulletMetaBase instance of the BulletMeta class is created by explicitly calling the metaclass when creating the Bullet baseclass (rather than using the __metaclass__= class attribute or via a metaclass keyword argument depending on the Python version).

class BulletMeta(type):
    def __new__(cls, classname, bases, classdict):
        """ Create Bullet class or a subclass of it. """
        classobj = type.__new__(cls, classname, bases, classdict)
        if classname != 'BulletMetaBase':
            if classname == 'Bullet':  # Base class definition?
                classobj.registry = {}  # Initialize subclass registry.
            else:
                try:
                    alias = classdict['alias']
                except KeyError:
                    raise TypeError("Bullet subclass %s has no 'alias'" %
                                    classname)
                if alias in Bullet.registry: # unique?
                    raise TypeError("Bullet subclass %s's alias attribute "
                                    "%r already in use" % (classname, alias))
                # Register subclass under the specified alias.
                classobj.registry[alias] = classobj

        return classobj

    def __call__(cls, alias, *args, **kwargs):
        """ Bullet subclasses instance factory.

            Subclasses should only be instantiated by calls to the base
            class with their subclass' alias as the first arg.
        """
        if cls != Bullet:
            raise TypeError("Bullet subclass %r objects should not to "
                            "be explicitly constructed." % cls.__name__)
        elif alias not in cls.registry: # Bullet subclass?
            raise NotImplementedError("Unknown Bullet subclass %r" %
                                      str(alias))
        # Create designated subclass object (call its __init__ method).
        subclass = cls.registry[alias]
        return type.__call__(subclass, *args, **kwargs)


class Bullet(BulletMeta('BulletMetaBase', (object,), {})):
    # Presumably you'd define some abstract methods that all here
    # that would be supported by all subclasses.
    # These definitions could just raise NotImplementedError() or
    # implement the functionality is some sub-optimal generic way.
    # For example:
    def fire(self, *args, **kwargs):
        raise NotImplementedError(self.__class__.__name__ + ".fire() method")

    # Abstract base class's __init__ should never be called.
    # If subclasses need to call super class's __init__() for some
    # reason then it would need to be implemented.
    def __init__(self, *args, **kwargs):
        raise NotImplementedError("Bullet is an abstract base class")


# Subclass definitions.
class Bullet1(Bullet):
    alias = 'B1'
    def __init__(self, sprite, start, direction, speed):
        print('creating %s object' % self.__class__.__name__)
    def fire(self, trajectory):
        print('Bullet1 object fired with %s trajectory' % trajectory)


class Bullet2(Bullet):
    alias = 'B2'
    def __init__(self, sprite, start, headto, spead, acceleration):
        print('creating %s object' % self.__class__.__name__)


class Bullet3(Bullet):
    alias = 'B3'
    def __init__(self, sprite, script): # script controlled bullets
        print('creating %s object' % self.__class__.__name__)


class Bullet4(Bullet):
    alias = 'B4'
    def __init__(self, sprite, curve, speed): # for bullets with curved paths
        print('creating %s object' % self.__class__.__name__)


class Sprite: pass
class Curve: pass

b1 = Bullet('B1', Sprite(), (10,20,30), 90, 600)
b2 = Bullet('B2', Sprite(), (-30,17,94), (1,-1,-1), 600, 10)
b3 = Bullet('B3', Sprite(), 'bullet42.script')
b4 = Bullet('B4', Sprite(), Curve(), 720)
b1.fire('uniform gravity')
b2.fire('uniform gravity')

Output:

creating Bullet1 object
creating Bullet2 object
creating Bullet3 object
creating Bullet4 object
Bullet1 object fired with uniform gravity trajectory
Traceback (most recent call last):
  File "python-function-overloading.py", line 93, in <module>
    b2.fire('uniform gravity') # NotImplementedError: Bullet2.fire() method
  File "python-function-overloading.py", line 49, in fire
    raise NotImplementedError(self.__class__.__name__ + ".fire() method")
NotImplementedError: Bullet2.fire() method

How to do a non-greedy match in grep?

Sorry I am 9 years late, but this might work for the viewers in 2020.

So suppose you have a line like "Hello my name is Jello". Now you want to find the words that start with 'H' and end with 'o', with any number of characters in between. And we don't want lines we just want words. So for that we can use the expression:

grep "H[^ ]*o" file

This will return all the words. The way this works is that: It will allow all the characters instead of space character in between, this way we can avoid multiple words in the same line.

Now you can replace the space character with any other character you want. Suppose the initial line was "Hello-my-name-is-Jello", then you can get words using the expression:

grep "H[^-]*o" file

Configure cron job to run every 15 minutes on Jenkins

Your syntax is slightly wrong. Say:

*/15 * * * * command
  |
  |--> `*/15` would imply every 15 minutes.

* indicates that the cron expression matches for all values of the field.

/ describes increments of ranges.

How can I hide the Android keyboard using JavaScript?

I've fixed like this, with this "$(input).prop('readonly',true);" in beforeShow

Ex:

$('input.datepicker').datepicker(
                        {   
                            changeMonth: false,
                            changeYear: false,
                            beforeShow: function(input, instance) { 
                                $(input).datepicker('setDate', new Date());
                                $(input).prop('readonly',true);
                            }
                        }                         
                     ); 

how to add css class to html generic control div?

If you're going to be repeating this, might as well have an extension method:

// appends a string class to the html controls class attribute
public static void AddClass(this HtmlControl control, string newClass)
{
    if (control.Attributes["class"].IsNotNullAndNotEmpty())
    {
        control.Attributes["class"] += " " + newClass;
    }
    else
    {
        control.Attributes["class"] = newClass;
    }
}

Error: Segmentation fault (core dumped)

In my case I imported pyxlsd module before module wich works with db Mysql. After I did put Mysql module first(upper in code) it became to work like a clock. Think there was some namespace issue.

Wordpress keeps redirecting to install-php after migration

This happened to me after I copy migrated an existing website to WP Engine and forgot to do one thing required by WP Engine:

Update the WordPress core installation of the site that is being copied to the latest version.

So here was the problem then:

My old site that I was copying from another server to WP Engine had version 4.0. However, when you copy an existing site to WP Engine, you don't copy the WordPress core files, you only copy the contents of wp-content and the state (or snapshot) of the existing database. So the state of the database for my existing site was for an installation running WP 4.0. Nevertheless, when you create a new WordPress install on WP Engine, that install is created with the latest version of WordPress, which, at the time happened to be version 4.0.1, so that means the core files on the destination (WP Engine) were for a 4.0.1 installation but the database snapshot I was gonna import into WP Engine was for version 4.0. So when I overwrote the default WP Engine database with the import of the copy the database of my old site, I got the redirection error to the install script.

So to fix it, I just logged into the WordPress admin site of the site on WP Engine, made sure to reset the file permissions (by clicking the blue button), which, you sometimes have to do on WP Engine, and then re-installed the WordPress core, which, basically updates your database so that internally the db state was for a WordPress 4.0.1 install and the core files also match the version.

Took me a while to figure out what was going on.

Iterating through a golang map

You could just write it out in multiline like this,

$ cat dict.go
package main

import "fmt"

func main() {
        items := map[string]interface{}{
                "foo": map[string]int{
                        "strength": 10,
                        "age": 2000,
                },
                "bar": map[string]int{
                        "strength": 20,
                        "age": 1000,
                },
        }
        for key, value := range items {
                fmt.Println("[", key, "] has items:")
                for k,v := range value.(map[string]int) {
                        fmt.Println("\t-->", k, ":", v)
                }

        }
}

And the output:

$ go run dict.go
[ foo ] has items:
        --> strength : 10
        --> age : 2000
[ bar ] has items:
        --> strength : 20
        --> age : 1000

Counting inversions in an array

Here's my O(n log n) solution in Ruby:

def solution(t)
    sorted, inversion_count = sort_inversion_count(t)
    return inversion_count
end

def sort_inversion_count(t)
    midpoint = t.length / 2
    left_half = t[0...midpoint]
    right_half = t[midpoint..t.length]

    if midpoint == 0
        return t, 0
    end

    sorted_left_half, left_half_inversion_count = sort_inversion_count(left_half)
    sorted_right_half, right_half_inversion_count = sort_inversion_count(right_half)

    sorted = []
    inversion_count = 0
    while sorted_left_half.length > 0 or sorted_right_half.length > 0
        if sorted_left_half.empty?
            sorted.push sorted_right_half.shift
        elsif sorted_right_half.empty?
            sorted.push sorted_left_half.shift
        else
            if sorted_left_half[0] > sorted_right_half[0]
                inversion_count += sorted_left_half.length
                sorted.push sorted_right_half.shift
            else
                sorted.push sorted_left_half.shift
            end
        end
    end

    return sorted, inversion_count + left_half_inversion_count + right_half_inversion_count
end

And some test cases:

require "minitest/autorun"

class TestCodility < Minitest::Test
    def test_given_example
        a = [-1, 6, 3, 4, 7, 4]
        assert_equal solution(a), 4
    end

    def test_empty
        a = []
        assert_equal solution(a), 0
    end

    def test_singleton
        a = [0]
        assert_equal solution(a), 0
    end

    def test_none
        a = [1,2,3,4,5,6,7]
        assert_equal solution(a), 0
    end

    def test_all
        a = [5,4,3,2,1]
        assert_equal solution(a), 10
    end

    def test_clones
        a = [4,4,4,4,4,4]
        assert_equal solution(a), 0
    end
end

How to style CSS role

we can use

 element[role="ourRole"] {
    requried style !important; /*for overriding the old css styles */
    }

Print text instead of value from C enum

i'm new to this but a switch statement will defenitely work

#include <stdio.h>

enum mycolor;

int main(int argc, const char * argv[])

{
enum Days{Sunday=1,Monday=2,Tuesday=3,Wednesday=4,Thursday=5,Friday=6,Saturday=7};

enum Days TheDay;


printf("Please enter the day of the week (0 to 6)\n");

scanf("%d",&TheDay);

switch (TheDay)
 {

case Sunday:
        printf("the selected day is sunday");
        break;
    case Monday:
        printf("the selected day is monday");
        break;
    case Tuesday:
        printf("the selected day is Tuesday");
        break;
    case Wednesday:
        printf("the selected day is Wednesday");
        break;
    case Thursday:
        printf("the selected day is thursday");
        break;
    case Friday:
        printf("the selected day is friday");
        break;
    case Saturday:
        printf("the selected day is Saturaday");
        break;
    default:
        break;
}

return 0;
}

Why does checking a variable against multiple values with `OR` only check the first value?

("Jesse" or "jesse")

The above expression tests whether or not "Jesse" evaluates to True. If it does, then the expression will return it; otherwise, it will return "jesse". The expression is equivalent to writing:

"Jesse" if "Jesse" else "jesse"

Because "Jesse" is a non-empty string though, it will always evaluate to True and thus be returned:

>>> bool("Jesse")  # Non-empty strings evaluate to True in Python
True
>>> bool("")  # Empty strings evaluate to False
False
>>>
>>> ("Jesse" or "jesse")
'Jesse'
>>> ("" or "jesse")
'jesse'
>>>

This means that the expression:

name == ("Jesse" or "jesse")

is basically equivalent to writing this:

name == "Jesse"

In order to fix your problem, you can use the in operator:

# Test whether the value of name can be found in the tuple ("Jesse", "jesse")
if name in ("Jesse", "jesse"):

Or, you can lowercase the value of name with str.lower and then compare it to "jesse" directly:

# This will also handle inputs such as "JeSSe", "jESSE", "JESSE", etc.
if name.lower() == "jesse":

Bad Request - Invalid Hostname IIS7

I got this error when I tried to call a webservice using "localhost". I fixed it by using the actual IP instead (192.168...)

Set value of textarea in jQuery

I tried with .val() .text() .html() and had some bugs using jQuery to read or set value of a textarea... i endup using native js

$('#message').blur(function() {    
    if (this.value == '') { this.value = msg_greeting; }
});

sed one-liner to convert all uppercase to lowercase?

Here are many solutions :

To upercaser with perl, tr, sed and awk

perl -ne 'print uc'
perl -npe '$_=uc'
perl -npe 'tr/[a-z]/[A-Z]/'
perl -npe 'tr/a-z/A-Z/'
tr '[a-z]' '[A-Z]'
sed y/abcdefghijklmnopqrstuvwxyz/ABCDEFGHIJKLMNOPQRSTUVWXYZ/
sed 's/\([a-z]\)/\U\1/g'
sed 's/.*/\U&/'
awk '{print toupper($0)}'

To lowercase with perl, tr, sed and awk

perl -ne 'print lc'
perl -npe '$_=lc'
perl -npe 'tr/[A-Z]/[a-z]/'
perl -npe 'tr/A-Z/a-z/'
tr '[A-Z]' '[a-z]'
sed y/ABCDEFGHIJKLMNOPQRSTUVWXYZ/abcdefghijklmnopqrstuvwxyz/
sed 's/\([A-Z]\)/\L\1/g'
sed 's/.*/\L&/'
awk '{print tolower($0)}'

Complicated bash to lowercase :

while read v;do v=${v//A/a};v=${v//B/b};v=${v//C/c};v=${v//D/d};v=${v//E/e};v=${v//F/f};v=${v//G/g};v=${v//H/h};v=${v//I/i};v=${v//J/j};v=${v//K/k};v=${v//L/l};v=${v//M/m};v=${v//N/n};v=${v//O/o};v=${v//P/p};v=${v//Q/q};v=${v//R/r};v=${v//S/s};v=${v//T/t};v=${v//U/u};v=${v//V/v};v=${v//W/w};v=${v//X/x};v=${v//Y/y};v=${v//Z/z};echo "$v";done

Complicated bash to uppercase :

while read v;do v=${v//a/A};v=${v//b/B};v=${v//c/C};v=${v//d/D};v=${v//e/E};v=${v//f/F};v=${v//g/G};v=${v//h/H};v=${v//i/I};v=${v//j/J};v=${v//k/K};v=${v//l/L};v=${v//m/M};v=${v//n/N};v=${v//o/O};v=${v//p/P};v=${v//q/Q};v=${v//r/R};v=${v//s/S};v=${v//t/T};v=${v//u/U};v=${v//v/V};v=${v//w/W};v=${v//x/X};v=${v//y/Y};v=${v//z/Z};echo "$v";done

Simple bash to lowercase :

while read v;do echo "${v,,}"; done

Simple bash to uppercase :

while read v;do echo "${v^^}"; done

Note that ${v,} and ${v^} only change the first letter.

You should use it that way :

(while read v;do echo "${v,,}"; done) < input_file.txt > output_file.txt

How to get cookie expiration date / creation date from javascript?

One possibility is to delete to cookie you are looking for the expiration date from and rewrite it. Then you'll know the expiration date.

Getting JavaScript object key list

_x000D_
_x000D_
var obj = {
  key1: 'value1',
  key2: 'value2',
  key3: 'value3',
  key4: 'value4'
};
var keys = [];

for (var k in obj) keys.push(k);

console.log("total " + keys.length + " keys: " + keys);
_x000D_
_x000D_
_x000D_

How can I disable all views inside the layout?

This is a pretty delayed answer.But it might help someone. Many answers mentioned above seem to be good. But if your layout.xml has nested viewgroups. Then above answers may not provide full result. Hence i have posted my opinion as a snippet. With the code below one can disable all views (Including Nested ViewGroups).

NOTE: Try avoiding nested ViewGroups as they are not recommended.

 private void setEnableView(boolean b) {
    LinearLayout layout = (LinearLayout)findViewById(R.id.parent_container);
    ArrayList<ViewGroup> arrVg = new ArrayList<>();
    for (int i = 0; i < layout.getChildCount(); i++) {
        View child = layout.getChildAt(i);
        if (child instanceof ViewGroup) {
            ViewGroup vg = (ViewGroup) child;
            arrVg.add(vg);
        }
        child.setEnabled(b);
    }

    for (int j=0;j< arrVg.size();j++){
        ViewGroup vg = arrVg.get(j);
        for (int k = 0; k < vg.getChildCount(); k++) {
         vg.getChildAt(k).setEnabled(b);
        }
    }
}

ViewBag, ViewData and TempData

void Keep()

Calling this method with in the current action ensures that all the items in TempData are not removed at the end of the current request.

    @model MyProject.Models.EmpModel;
    @{
    Layout = "~/Views/Shared/_Layout.cshtml";
    ViewBag.Title = "About";
    var tempDataEmployeet = TempData["emp"] as Employee; //need typcasting
    TempData.Keep(); // retains all strings values
    } 

void Keep(string key)

Calling this method with in the current action ensures that specific item in TempData is not removed at the end of the current request.

    @model MyProject.Models.EmpModel;
    @{
    Layout = "~/Views/Shared/_Layout.cshtml";
    ViewBag.Title = "About";
    var tempDataEmployeet = TempData["emp"] as Employee; //need typcasting
    TempData.Keep("emp"); // retains only "emp" string values
    } 

Working with select using AngularJS's ng-options

In CoffeeScript:

#directive
app.directive('select2', ->
    templateUrl: 'partials/select.html'
    restrict: 'E'
    transclude: 1
    replace: 1
    scope:
        options: '='
        model: '='
    link: (scope, el, atr)->
        el.bind 'change', ->
            console.log this.value
            scope.model = parseInt(this.value)
            console.log scope
            scope.$apply()
)
<!-- HTML partial -->
<select>
  <option ng-repeat='o in options'
          value='{{$index}}' ng-bind='o'></option>
</select>

<!-- HTML usage -->
<select2 options='mnuOffline' model='offlinePage.toggle' ></select2>

<!-- Conclusion -->
<p>Sometimes it's much easier to create your own directive...</p>

Oracle - how to remove white spaces?

I have used below command to remove white space in Oracle

My Table Name is - NG_CAP_SENDER_INFO_MTR

My Column Name is - SENINFO_FROM

UPDATE NG_CAP_SENDER_INFO_MTR SET SENINFO_FROM = TRIM(SENINFO_FROM); 

Already Answer on StackOverflow LTRIM RTRIM

And its working fine

How do I display the value of a Django form field in a template?

This was a feature request that got fixed in Django 1.3.

Here's the bug: https://code.djangoproject.com/ticket/10427

Basically, if you're running something after 1.3, in Django templates you can do:

{{ form.field.value|default_if_none:"" }}

Or in Jinja2:

{{ form.field.value()|default("") }}

Note that field.value() is a method, but in Django templates ()'s are omitted, while in Jinja2 method calls are explicit.

If you want to know what version of Django you're running, it will tell you when you do the runserver command.

If you are on something prior to 1.3, you can probably use the fix posted in the above bug: https://code.djangoproject.com/ticket/10427#comment:24

How to solve privileges issues when restore PostgreSQL Database

You can probably safely ignore the error messages in this case. Failing to add a comment to the public schema and installing plpgsql (which should already be installed) aren't going to cause any real problems.

However, if you want to do a complete re-install you'll need a user with appropriate permissions. That shouldn't be the user your application routinely runs as of course.

A server with the specified hostname could not be found

It might be DNS Pollution issue, at least for my case (in China).

If you're also in China or some places that has DNS Pollution issue, you might solve this by modifying the DNS (to 8.8.8.8 as an example) for your Mac as well.


I got this error inner my iPad App & this happens randomly, it's such boring. Keep trying is not a good solution for me, though it might works somehow. Finally, I just changed my Wi-Fi DNS and no more error now. Steps:

  1. Your device, Settings/Wi-Fi
  2. Choose connected Wi-Fi pot
  3. Press DHCP/DNS
  4. Set to 8.8.8.8

remove legend title in ggplot

Another option using labs and setting colour to NULL.

ggplot(df, aes(x, y, colour = g)) +
  geom_line(stat = "identity") +
  theme(legend.position = "bottom") +
  labs(colour = NULL)

enter image description here

Execute Immediate within a stored procedure keeps giving insufficient priviliges error

Alternatively you can grant the user DROP_ANY_TABLE privilege if need be and the procedure will run as is without the need for any alteration. Dangerous maybe but depends what you're doing :)

What's the difference between the Window.Loaded and Window.ContentRendered events

If you visit this link https://msdn.microsoft.com/library/ms748948%28v=vs.100%29.aspx#Window_Lifetime_Events and scroll down to Window Lifetime Events it will show you the event order.

Open:

  1. SourceInitiated
  2. Activated
  3. Loaded
  4. ContentRendered

Close:

  1. Closing
  2. Deactivated
  3. Closed

Set position / size of UI element as percentage of screen size

For TextView and it's descendants (e.g., Button) you can get the display size from the WindowManager and then set the TextView height to be some fraction of it:

Button btn = new Button (this);
android.view.Display display = ((android.view.WindowManager)getSystemService(Context.WINDOW_SERVICE)).getDefaultDisplay(); 
btn.setHeight((int)(display.getHeight()*0.68));

Change image source with JavaScript

The problem was that you were using .src without needing it and you also needed to differentiate which img you wanted to change.

function changeImage(a, imgid) {
    document.getElementById(imgid).src=a;
}
<div id="main_img">
    <img id="img" src="1772031_29_b.jpg">
</div>
<div id="thumb_img">
    <img id="1" src='1772031_29_t.jpg'  onclick='changeImage("1772031_29_b.jpg", "1");'>
    <img id="2" src='1772031_55_t.jpg'  onclick='changeImage("1772031_55_b.jpg", "2");'>
    <img id="3" src='1772031_53_t.jpg'  onclick='changeImage("1772031_53_b.jpg", "3");'>
</div>

How can I have Github on my own server?

You can run Git (not the whole Github) via Apache HTTP Server, so that you host the Git repo on your server's filesystem and expose it via HTTP. You get all Git functionalities, but obviously you won't be able to pull-request or track issues. Any tool attached to your self-hosted Git repo can implement the rest of the features.

Reference: http://git-scm.com/docs/git-http-backend

Sending mail from Python using SMTP

The script I use is quite similar; I post it here as an example of how to use the email.* modules to generate MIME messages; so this script can be easily modified to attach pictures, etc.

I rely on my ISP to add the date time header.

My ISP requires me to use a secure smtp connection to send mail, I rely on the smtplib module (downloadable at http://www1.cs.columbia.edu/~db2501/ssmtplib.py)

As in your script, the username and password, (given dummy values below), used to authenticate on the SMTP server, are in plain text in the source. This is a security weakness; but the best alternative depends on how careful you need (want?) to be about protecting these.

=======================================

#! /usr/local/bin/python


SMTPserver = 'smtp.att.yahoo.com'
sender =     'me@my_email_domain.net'
destination = ['recipient@her_email_domain.com']

USERNAME = "USER_NAME_FOR_INTERNET_SERVICE_PROVIDER"
PASSWORD = "PASSWORD_INTERNET_SERVICE_PROVIDER"

# typical values for text_subtype are plain, html, xml
text_subtype = 'plain'


content="""\
Test message
"""

subject="Sent from Python"

import sys
import os
import re

from smtplib import SMTP_SSL as SMTP       # this invokes the secure SMTP protocol (port 465, uses SSL)
# from smtplib import SMTP                  # use this for standard SMTP protocol   (port 25, no encryption)

# old version
# from email.MIMEText import MIMEText
from email.mime.text import MIMEText

try:
    msg = MIMEText(content, text_subtype)
    msg['Subject']=       subject
    msg['From']   = sender # some SMTP servers will do this automatically, not all

    conn = SMTP(SMTPserver)
    conn.set_debuglevel(False)
    conn.login(USERNAME, PASSWORD)
    try:
        conn.sendmail(sender, destination, msg.as_string())
    finally:
        conn.quit()

except:
    sys.exit( "mail failed; %s" % "CUSTOM_ERROR" ) # give an error message

Read Session Id using Javascript

Here's a short and sweet JavaScript function to fetch the session ID:

function session_id() {
    return /SESS\w*ID=([^;]+)/i.test(document.cookie) ? RegExp.$1 : false;
}

Or if you prefer a variable, here's a simple one-liner:

var session_id = /SESS\w*ID=([^;]+)/i.test(document.cookie) ? RegExp.$1 : false;

Should match the session ID cookie for PHP, JSP, .NET, and I suppose various other server-side processors as well.

Angularjs - ng-cloak/ng-show elements blink

Though the documentation doesn't mention it, it might not be enough to add the display: none; rule to your CSS. In cases where you are loading angular.js in the body or templates aren't compiled soon enough, use the ng-cloak directive and include the following in your CSS:

/* 
  Allow angular.js to be loaded in body, hiding cloaked elements until 
  templates compile.  The !important is important given that there may be 
  other selectors that are more specific or come later and might alter display.  
 */
[ng\:cloak], [ng-cloak], .ng-cloak {
  display: none !important;
}

As mentioned in the comment, the !important is important. For example, if you have the following markup

<ul class="nav">
  <li><a href="/foo" ng-cloak>{{bar}}</a></li>
</ul>

and you happen to be using bootstrap.css, the following selector is more specific for your ng-cloak'ed element

.nav > li > a {
  display: block;
}

So if you include a rule with simply display: none;, Bootstrap's rule will take precedence and the display will be set to block, so you'll see the flicker before the template compiles.

Checking if a textbox is empty in Javascript

onchange will work only if the value of the textbox changed compared to the value it had before, so for the first time it won't work because the state didn't change.

So it is better to use onblur event or on submitting the form.

_x000D_
_x000D_
function checkTextField(field) {_x000D_
  document.getElementById("error").innerText =_x000D_
    (field.value === "") ? "Field is empty." : "Field is filled.";_x000D_
}
_x000D_
<input type="text" onblur="checkTextField(this);" />_x000D_
<p id="error"></p>
_x000D_
_x000D_
_x000D_

(Or old live demo.)

Differences between MySQL and SQL Server

@abdu

The main thing I've found that MySQL has over MSSQL is timezone support - the ability to nicely change between timezones, respecting daylight savings is fantastic.

Compare this:

mysql> SELECT CONVERT_TZ('2008-04-01 12:00:00', 'UTC', 'America/Los_Angeles');
+-----------------------------------------------------------------+
| CONVERT_TZ('2008-04-01 12:00:00', 'UTC', 'America/Los_Angeles') |
+-----------------------------------------------------------------+
| 2008-04-01 05:00:00                                             |
+-----------------------------------------------------------------+

to the contortions involved at this answer.

As for the 'easier to use' comment, I would say that the point is that they are different, and if you know one, there will be an overhead in learning the other.

Read input stream twice

If you are using RestTemplate to make http calls Simply add an interceptor. Response body is cached by the implementation of ClientHttpResponse. Now inputstream can be retrieved from respose as many times as we need

ClientHttpRequestInterceptor interceptor =  new ClientHttpRequestInterceptor() {

            @Override
            public ClientHttpResponse intercept(HttpRequest request, byte[] body,
                    ClientHttpRequestExecution execution) throws IOException {
                ClientHttpResponse  response = execution.execute(request, body);

                  // additional work before returning response
                  return response 
            }
        };

    // Add the interceptor to RestTemplate Instance 

         restTemplate.getInterceptors().add(interceptor); 

Finding child element of parent pure javascript

The children property returns an array of elements, like so:

parent = document.querySelector('.parent');
children = parent.children; // [<div class="child1">]

There are alternatives to querySelector, like document.getElementsByClassName('parent')[0] if you so desire.


Edit: Now that I think about it, you could just use querySelectorAll to get decendents of parent having a class name of child1:

children = document.querySelectorAll('.parent .child1');

The difference between qS and qSA is that the latter returns all elements matching the selector, while the former only returns the first such element.

Find Item in ObservableCollection without using a loop

An observablecollection can be a List

{
    BuchungsSatz item = BuchungsListe.ToList.Find(x => x.BuchungsAuftragId == DGBuchungenAuftrag.CurrentItem.Id);
}

How do I make a Windows batch script completely silent?

Copies a directory named html & all its contents to a destination directory in silent mode. If the destination directory is not present it will still create it.

@echo off
TITLE Copy Folder with Contents

set SOURCE=C:\labs
set DESTINATION=C:\Users\MyUser\Desktop\html

xcopy %SOURCE%\html\* %DESTINATION%\* /s /e /i /Y >NUL

  1. /S Copies directories and subdirectories except empty ones.

  2. /E Copies directories and subdirectories, including empty ones. Same as /S /E. May be used to modify /T.

  3. /I If destination does not exist and copying more than one file, assumes that destination must be a directory.

  4. /Y Suppresses prompting to confirm you want to overwrite an existing destination file.

How can I convert a date to GMT?

I am trying with the below. This seems to be working fine. Are there any limitations to this approach? Please confirm.

var now=new Date();                         // Sun Apr 02 2017 2:00:00 GMT+1000 (AEST)
var gmtRe = /GMT([\-\+]?\d{4})/;
var tz = gmtRe.exec(now)[1];               // +1000
var hour=tz/100;                           // 10
var min=tz%100;                            // 0
now.setHours(now.getHours()-hour);
now.setMinutes(now.getMinutes()-min);      // Sat Apr 01 2017 16:00:00 GMT

How to create virtual column using MySQL SELECT?

Something like:

SELECT id, email, IF(active = 1, 'enabled', 'disabled') AS account_status FROM users

This allows you to make operations and show it as columns.

EDIT:

you can also use joins and show operations as columns:

SELECT u.id, e.email, IF(c.id IS NULL, 'no selected', c.name) AS country
FROM users u LEFT JOIN countries c ON u.country_id = c.id

Biggest differences of Thrift vs Protocol Buffers?

I think the basic data structure is different

  1. Protocol Buffer use variable-length integee which refers to variable-length digital encoding, turning a fixed-length number into a variable-length number to save space.
  2. Thrift proposed different types of serialization formats (called "protocols"). In fact, Thrift has two different JSON encodings, and no less than three different binary encoding methods.

In conclusion,these two libraries are completely different. Thrift likes a one-stop shop, giving you the entire integrated RPC framework and many options (supporting cross-language), while Protocol Buffers is more inclined to "just do one thing and do it well".

Console.WriteLine does not show up in Output window

If you intend to use this output in production, then use the Trace class members. This makes the code portable, you can wire up different types of listeners and output to the console window, debug window, log file, or whatever else you like.

If this is just some temporary debugging code that you're using to verify that certain code is being executed or has the correct values, then use the Debug class as Zach suggests.

If you absolutely must use the console, then you can attach a console in the program's Main method.

expected constructor, destructor, or type conversion before ‘(’ token

You are missing the std namespace reference in the cc file. You should also call nom.c_str() because there is no implicit conversion from std::string to const char * expected by ifstream's constructor.

Polygone::Polygone(std::string nom) {
    std::ifstream fichier (nom.c_str(), std::ifstream::in);
    // ...
}

How can I right-align text in a DataGridView column?

<DataGridTextColumn Header="Quantity" Binding="{Binding Quantity}" >
  <DataGridTextColumn.ElementStyle>
    <Style TargetType="{x:Type TextBlock}">
       <Setter Property="HorizontalAlignment" Value="Right" />
    </Style>
  </DataGridTextColumn.ElementStyle>
</DataGridTextColumn>

Java Hashmap: How to get key from value?

For Android development targeting API < 19, Vitalii Fedorenko one-to-one relationship solution doesn't work because Objects.equals isn't implemented. Here's a simple alternative:

public <K, V> K getKeyByValue(Map<K, V> map, V value) {
    for (Map.Entry<K, V> entry : map.entrySet()) {
            if (value.equals(entry.getValue())) {
            return entry.getKey();
        }
    }
    return null;
}

How to solve javax.net.ssl.SSLHandshakeException Error?

Now I solved this issue in this way,

import javax.net.ssl.HttpsURLConnection;
import javax.net.ssl.SSLContext;
import javax.net.ssl.TrustManager;
import javax.net.ssl.X509TrustManager;
import java.io.OutputStream;
// Create a trust manager that does not validate certificate chains like the 
default TrustManager[] trustAllCerts = new TrustManager[] {
    new X509TrustManager() {
        public java.security.cert.X509Certificate[] getAcceptedIssuers() {
            return null;
        }
        public void checkClientTrusted(java.security.cert.X509Certificate[] certs, String authType) {
            //No need to implement. 
        }
        public void checkServerTrusted(java.security.cert.X509Certificate[] certs, String authType) {
            //No need to implement. 
        }
    }
};
// Install the all-trusting trust manager
try {
    SSLContext sc = SSLContext.getInstance("SSL");
    sc.init(null, trustAllCerts, new java.security.SecureRandom());
    HttpsURLConnection.setDefaultSSLSocketFactory(sc.getSocketFactory());
} catch (Exception e) {
    System.out.println(e);
}

AttributeError: 'str' object has no attribute 'strftime'

You should use datetime object, not str.

>>> from datetime import datetime
>>> cr_date = datetime(2013, 10, 31, 18, 23, 29, 227)
>>> cr_date.strftime('%m/%d/%Y')
'10/31/2013'

To get the datetime object from the string, use datetime.datetime.strptime:

>>> datetime.strptime(cr_date, '%Y-%m-%d %H:%M:%S.%f')
datetime.datetime(2013, 10, 31, 18, 23, 29, 227)
>>> datetime.strptime(cr_date, '%Y-%m-%d %H:%M:%S.%f').strftime('%m/%d/%Y')
'10/31/2013'

Why does instanceof return false for some literals?

Primitives are a different kind of type than objects created from within Javascript. From the Mozilla API docs:

var color1 = new String("green");
color1 instanceof String; // returns true
var color2 = "coral";
color2 instanceof String; // returns false (color2 is not a String object)

I can't find any way to construct primitive types with code, perhaps it's not possible. This is probably why people use typeof "foo" === "string" instead of instanceof.

An easy way to remember things like this is asking yourself "I wonder what would be sane and easy to learn"? Whatever the answer is, Javascript does the other thing.

Refresh an asp.net page on button click

When you say refresh the page, its new instance of the page that you are creating so you need to either have a static variable/session variable or a method to store and retrieve the count of hits on your page.

As far as refreshing the page is concerned, Response.Redirect(Request.RawUrl); or window.location=window.location would do the job for you.

Draw an X in CSS

You want an entity known as a cross mark:

http://www.fileformat.info/info/unicode/char/274c/index.htm

The code for it is &#10060; and it displays like ❌

If you want a perfectly centered cross mark, like this:

cross mark demo

try the following CSS:

div {
    height: 100px;
    width: 100px;
    background-color: #FA6900;
    border-radius: 5px;
    position: relative;
}

div:after {
    position: absolute;
    top: 0;
    bottom: 0;
    left: 0;
    right: 0;
    content: "\274c"; /* use the hex value here... */
    font-size: 50px; 
    color: #FFF;
    line-height: 100px;
    text-align: center;
}

See Demo Fiddle

Cross-Browser Issue

The cross-mark entity does not display with Safari or Chrome. However, the same entity displays well in Firefox, IE and Opera.

It is safe to use the smaller but similarly shaped multiplication sign entity, &#xd7; which displays as ×.

How do I disable "missing docstring" warnings at a file-level in Pylint?

Go to file "settings.json" and disable the Python pydocstyle:

"python.linting.pydocstyleEnabled": false

Creating new table with SELECT INTO in SQL

The syntax for creating a new table is

CREATE TABLE new_table
AS
SELECT *
  FROM old_table

This will create a new table named new_table with whatever columns are in old_table and copy the data over. It will not replicate the constraints on the table, it won't replicate the storage attributes, and it won't replicate any triggers defined on the table.

SELECT INTO is used in PL/SQL when you want to fetch data from a table into a local variable in your PL/SQL block.

cut or awk command to print first field of first row

sed -n 1p /etc/*release |cut -d " " -f1

if tab delimited:

sed -n 1p /etc/*release |cut -f1

Close a MessageBox after several seconds

I did it like this

var owner = new Form { TopMost = true };
Task.Delay(30000).ContinueWith(t => {
owner.Invoke(new Action(()=>
{
      if (!owner.IsDisposed)
      {
          owner.Close();
      }
   }));
});
var dialogRes =  MessageBox.Show(owner, msg, "Info", MessageBoxButtons.YesNo, MessageBoxIcon.Information);

Get a list of resources from classpath directory

Custom Scanner

Implement your own scanner. For example:

(limitations of this solution are mentioned in the comments)

private List<String> getResourceFiles(String path) throws IOException {
    List<String> filenames = new ArrayList<>();

    try (
            InputStream in = getResourceAsStream(path);
            BufferedReader br = new BufferedReader(new InputStreamReader(in))) {
        String resource;

        while ((resource = br.readLine()) != null) {
            filenames.add(resource);
        }
    }

    return filenames;
}

private InputStream getResourceAsStream(String resource) {
    final InputStream in
            = getContextClassLoader().getResourceAsStream(resource);

    return in == null ? getClass().getResourceAsStream(resource) : in;
}

private ClassLoader getContextClassLoader() {
    return Thread.currentThread().getContextClassLoader();
}

Spring Framework

Use PathMatchingResourcePatternResolver from Spring Framework.

Ronmamo Reflections

The other techniques might be slow at runtime for huge CLASSPATH values. A faster solution is to use ronmamo's Reflections API, which precompiles the search at compile time.

is it possible to get the MAC address for machine using nmap

With the recent version of nmap 6.40, it will automatically show you the MAC address. example:

nmap 192.168.0.1-255

this command will scan your network from 192.168.0.1 to 255 and will display the hosts with their MAC address on your network.

in case you want to display the mac address for a single client, use this command make sure you are on root or use "sudo"

sudo nmap -Pn 192.168.0.1

this command will display the host MAC address and the open ports.

hope that is helpful.

Referencing value in a closed Excel workbook using INDIRECT?

If you know the number of sheet you want to reference you can use below function to find out the name. Than you can use it in INDIRECT funcion.

Public Function GETSHEETNAME(address As String, Optional SheetNumber As Integer = 1) As String

    Set WS = GetObject(address).Worksheets
    GETSHEETNAME = WS(SheetNumber).Name

End Function

This solution doesn't require referenced workbook to be open - Excel gonna open it by itself (but it's gonna be hidden).

How do I parse command line arguments in Java?

If you want something lightweight (jar size ~ 20 kb) and simple to use, you can try argument-parser. It can be used in most of the use cases, supports specifying arrays in the argument and has no dependency on any other library. It works for Java 1.5 or above. Below excerpt shows an example on how to use it:

public static void main(String[] args) {
    String usage = "--day|-d day --mon|-m month [--year|-y year][--dir|-ds directoriesToSearch]";
    ArgumentParser argParser = new ArgumentParser(usage, InputData.class);
    InputData inputData = (InputData) argParser.parse(args);
    showData(inputData);

    new StatsGenerator().generateStats(inputData);
}

More examples can be found here

Best way to store data locally in .NET (C#)

My first inclination is an access database. The .mdb files are stored locally, and can be encrypted if that is deemed necessary. Though XML or JSON would also work for many scenarios. Flat files I would only use for read only, non-search (forward read only) information. I tend to prefer csv format to set width.

Static methods - How to call a method from another method?

You can’t call non-static methods from static methods, but by creating an instance inside the static method.

It should work like that

class test2(object):
    def __init__(self):
        pass

    @staticmethod
    def dosomething():
        print "do something"
        # Creating an instance to be able to
        # call dosomethingelse(), or you
        # may use any existing instance
        a = test2()
        a.dosomethingelse()

    def dosomethingelse(self):
        print "do something else"

test2.dosomething()

How can I selectively escape percent (%) in Python strings?

I have tried different methods to print a subplot title, look how they work. It's different when i use Latex.

It works with '%%' and 'string'+'%' in a typical case.

If you use Latex it worked using 'string'+'\%'

So in a typical case:

import matplotlib.pyplot as plt
fig,ax = plt.subplots(4,1)
float_number = 4.17
ax[0].set_title('Total: (%1.2f' %float_number + '\%)')
ax[1].set_title('Total: (%1.2f%%)' %float_number)
ax[2].set_title('Total: (%1.2f' %float_number + '%%)')
ax[3].set_title('Total: (%1.2f' %float_number + '%)')

Title examples with %

If we use latex:

import matplotlib.pyplot as plt
import matplotlib
font = {'family' : 'normal',
        'weight' : 'bold',
        'size'   : 12}
matplotlib.rc('font', **font)
matplotlib.rcParams['text.usetex'] = True
matplotlib.rcParams['text.latex.unicode'] = True
fig,ax = plt.subplots(4,1)
float_number = 4.17
#ax[0].set_title('Total: (%1.2f\%)' %float_number) This makes python crash
ax[1].set_title('Total: (%1.2f%%)' %float_number)
ax[2].set_title('Total: (%1.2f' %float_number + '%%)')
ax[3].set_title('Total: (%1.2f' %float_number + '\%)')

We get this: Title example with % and latex

Parsing a comma-delimited std::string

You could also use the following function.

void tokenize(const string& str, vector<string>& tokens, const string& delimiters = ",")
{
  // Skip delimiters at beginning.
  string::size_type lastPos = str.find_first_not_of(delimiters, 0);

  // Find first non-delimiter.
  string::size_type pos = str.find_first_of(delimiters, lastPos);

  while (string::npos != pos || string::npos != lastPos) {
    // Found a token, add it to the vector.
    tokens.push_back(str.substr(lastPos, pos - lastPos));

    // Skip delimiters.
    lastPos = str.find_first_not_of(delimiters, pos);

    // Find next non-delimiter.
    pos = str.find_first_of(delimiters, lastPos);
  }
}

correct way to use super (argument passing)

Sometimes two classes may have some parameter names in common. In that case, you can't pop the key-value pairs off of **kwargs or remove them from *args. Instead, you can define a Base class which unlike object, absorbs/ignores arguments:

class Base(object):
    def __init__(self, *args, **kwargs): pass

class A(Base):
    def __init__(self, *args, **kwargs):
        print "A"
        super(A, self).__init__(*args, **kwargs)

class B(Base):
    def __init__(self, *args, **kwargs):
        print "B"
        super(B, self).__init__(*args, **kwargs)

class C(A):
    def __init__(self, arg, *args, **kwargs):
        print "C","arg=",arg
        super(C, self).__init__(arg, *args, **kwargs)

class D(B):
    def __init__(self, arg, *args, **kwargs):
        print "D", "arg=",arg
        super(D, self).__init__(arg, *args, **kwargs)

class E(C,D):
    def __init__(self, arg, *args, **kwargs):
        print "E", "arg=",arg
        super(E, self).__init__(arg, *args, **kwargs)

print "MRO:", [x.__name__ for x in E.__mro__]
E(10)

yields

MRO: ['E', 'C', 'A', 'D', 'B', 'Base', 'object']
E arg= 10
C arg= 10
A
D arg= 10
B

Note that for this to work, Base must be the penultimate class in the MRO.

How to convert hex to ASCII characters in the Linux shell?

You can use this command (python script) for larger inputs:

echo 58595a | python -c "import sys; import binascii; print(binascii.unhexlify(sys.stdin.read().strip()).decode())"

The result will be:

XYZ

And for more simplicity, define an alias:

alias hexdecoder='python -c "import sys; import binascii; print(binascii.unhexlify(sys.stdin.read().strip()).decode())"'

echo 58595a | hexdecoder

Where can I get a virtual machine online?

You can get free Virtual Machine and many more things online for 3 months provided by Microsoft Azure. I guess you need VPN for learning purpose. For that it would suffice.

Refer http://www.windowsazure.com/en-us/pricing/free-trial/

Find maximum value of a column and return the corresponding row values using Pandas

In order to print the Country and Place with maximum value, use the following line of code.

print(df[['Country', 'Place']][df.Value == df.Value.max()])

Padding zeros to the left in postgreSQL

You can use the rpad and lpad functions to pad numbers to the right or to the left, respectively. Note that this does not work directly on numbers, so you'll have to use ::char or ::text to cast them:

SELECT RPAD(numcol::text, 3, '0'), -- Zero-pads to the right up to the length of 3
       LPAD(numcol::text, 3, '0'), -- Zero-pads to the left up to the length of 3
FROM   my_table

Python method for reading keypress?

It's really late now but I made a quick script which works for Windows, Mac and Linux, simply by using each command line:

import os, platform

def close():
    if platform.system() == "Windows":
        print("Press any key to exit . . .")
        os.system("pause>nul")
        exit()
    
    elif platform.system() == "Linux":
        os.system("read -n1 -r -p \"Press any key to exit . . .\" key")
        exit()
    
    elif platform.system() == "Darwin":
        print("Press any key to exit . . .")
        os.system("read -n 1 -s -p \"\"")
        exit()
    
    else:
        exit()

It uses only inbuilt functions, and should work for all three (although I've only tested Windows and Linux...).

Capturing mobile phone traffic on Wireshark

Another option which has not been suggested here is to run the app you want to monitor in the Android emulator from the Android SDK. You can then easily capture the traffic with wireshark on the same machine.

This was the easiest option for me.

How to import local packages in go?

If you are using Go 1.5 above, you can try to use vendoring feature. It allows you to put your local package under vendor folder and import it with shorter path. In your case, you can put your common and routers folder inside vendor folder so it would be like

myapp/
--vendor/
----common/
----routers/
------middleware/
--main.go

and import it like this

import (
    "common"
    "routers"
    "routers/middleware"
)

This will work because Go will try to lookup your package starting at your project’s vendor directory (if it has at least one .go file) instead of $GOPATH/src.

FYI: You can do more with vendor, because this feature allows you to put "all your dependency’s code" for a package inside your own project's directory so it will be able to always get the same dependencies versions for all builds. It's like npm or pip in python, but you need to manually copy your dependencies to you project, or if you want to make it easy, try to look govendor by Daniel Theophanes

For more learning about this feature, try to look up here

Understanding and Using Vendor Folder by Daniel Theophanes

Understanding Go Dependency Management by Lucas Fernandes da Costa

I hope you or someone else find it helpfully

You don't have write permissions for the /Library/Ruby/Gems/2.3.0 directory. (mac user)

Update: I've since written a very detailed explanation of the various ways you can install Ruby gems on a Mac. My original recommendation to use a script still stands, but my article goes into more detail: https://www.moncefbelyamani.com/the-definitive-guide-to-installing-ruby-gems-on-a-mac/

You are correct that macOS won't let you change anything with the Ruby version that comes installed with your Mac. However, it's possible to install gems like bundler using a separate version of Ruby that doesn't interfere with the one provided by Apple.

Using sudo to install gems, or changing permissions of system files and directories is strongly discouraged, even if you know what you are doing. Can we please stop providing this bad advice? Here's a detailed article I wrote showing how sudo gem install can wipe out your computer: https://www.moncefbelyamani.com/why-you-should-never-use-sudo-to-install-ruby-gems/

The solution involves two main steps:

  1. Install a separate version of Ruby that does not interfere with the one that came with your Mac.
  2. Update your PATH such that the location of the new Ruby version is first in the PATH. Some tools do this automatically for you. If you're not familiar with the PATH and how it works, read my guide.

There are several ways to install Ruby on a Mac. The best way that I recommend, and that I wish was more prevalent in the various installation instructions out there, is to use an automated script that will set up a proper Ruby environment for you. This drastically reduces the chances of running into an error due to inadequate instructions that make the user do a bunch of stuff manually and leaving it up to them to figure out all the necessary steps.

The other route you can take is to spend extra time doing everything manually and hoping for the best. First, you will want to install Homebrew, which installs the prerequisite command line tools, and makes it easy to install other necessary tools.

Then, the two easiest ways to install a separate version of Ruby are:

If you would like the flexibility of easily switching between many Ruby versions [RECOMMENDED]

Choose one of these four options:

  • chruby and ruby-install - my personal recommendations and the ones that are automatically installed by my script. These can be installed with Homebrew:
brew install chruby ruby-install

If you chose chruby and ruby-install, you can then install the latest Ruby like this:

ruby-install ruby

Once you've installed everything and configured your .zshrc or .bash_profile according to the instructions from the tools above, quit and restart Terminal, then switch to the version of Ruby that you want. In the case of chruby, it would be something like this:

chruby 2.7.2

Whether you need to configure .zshrc or .bash_profile depends on which shell you are using. If you're not sure, read this guide: https://www.moncefbelyamani.com/which-shell-am-i-using-how-can-i-switch/

If you know for sure you don't need more than one version of Ruby at the same time (besides the one that came with macOS)

  • Install ruby with Homebrew:
brew install ruby

Then update your PATH by running (replace 2.7.0 with your newly installed version):

echo 'export PATH="/usr/local/opt/ruby/bin:/usr/local/lib/ruby/gems/2.7.0/bin:$PATH"' >> ~/.zshrc

Then "refresh" your shell for these changes to take effect:

source ~/.zshrc

Or you can open a new terminal tab, or quit and restart Terminal.

Replace .zshrc with .bash_profile if you are using Bash. If you're not sure which shell you are using, read this guide: https://www.moncefbelyamani.com/which-shell-am-i-using-how-can-i-switch/

To check that you're now using the non-system version of Ruby, you can run the following commands:

which ruby

It should be something other than /usr/bin/ruby

ruby -v

It should be something other than 2.6.3 if you're on macOS Catalina. As of today, 2.7.2 is the latest Ruby version.

Once you have this new version of Ruby installed, you can now install bundler (or any other gem):

gem install bundler

PowerShell: Format-Table without headers

Another approach is to use ForEach-Object to project individual items to a string and then use the Out-String CmdLet to project the final results to a string or string array:

gci Microsoft.PowerShell.Core\Registry::HKEY_CLASSES_ROOT\CID | foreach { "CID Key {0}" -f $_.Name } | Out-String

#Result: One multi-line string equal to:
@"
CID Key HKEY_CLASSES_ROOT\CID\2a621c8a-7d4b-4d7b-ad60-a957fd70b0d0
CID Key HKEY_CLASSES_ROOT\CID\2ec6f5b2-8cdc-461e-9157-ffa84c11ba7d
CID Key HKEY_CLASSES_ROOT\CID\5da2ceaf-bc35-46e0-aabd-bd826023359b
CID Key HKEY_CLASSES_ROOT\CID\d13ad82e-d4fb-495f-9b78-01d2946e6426
"@

gci Microsoft.PowerShell.Core\Registry::HKEY_CLASSES_ROOT\CID | foreach { "CID Key {0}" -f $_.Name } | Out-String -Stream

#Result: An array of single line strings equal to:
@(
"CID Key HKEY_CLASSES_ROOT\CID\2a621c8a-7d4b-4d7b-ad60-a957fd70b0d0",
"CID Key HKEY_CLASSES_ROOT\CID\2ec6f5b2-8cdc-461e-9157-ffa84c11ba7d",
"CID Key HKEY_CLASSES_ROOT\CID\5da2ceaf-bc35-46e0-aabd-bd826023359b",
"CID Key HKEY_CLASSES_ROOT\CID\d13ad82e-d4fb-495f-9b78-01d2946e6426")

The benefit of this approach is that you can store the result to a variable and it will NOT have any empty lines.

How to remove/ignore :hover css style on touch devices

This is also a possible workaround, but you will have to go through your css and add a .no-touch class before your hover styles.

Javascript:

if (!("ontouchstart" in document.documentElement)) {
document.documentElement.className += " no-touch";
}

CSS Example:

<style>
p span {
    display: none;
}

.no-touch p:hover span {
    display: inline;
}
</style>
<p><a href="/">Tap me</a><span>You tapped!</span></p>

Source

P.s. But we should remember, there are coming more and more touch-devices to the market, which are also supporting mouse input at the same time.

Why do I get AttributeError: 'NoneType' object has no attribute 'something'?

The NoneType is the type of the value None. In this case, the variable lifetime has a value of None.

A common way to have this happen is to call a function missing a return.

There are an infinite number of other ways to set a variable to None, however.

Get random sample from list while maintaining ordering of items?

Maybe you can just generate the sample of indices and then collect the items from your list.

randIndex = random.sample(range(len(mylist)), sample_size)
randIndex.sort()
rand = [mylist[i] for i in randIndex]

Oracle: not a valid month

1.

To_Date(To_Char(MaxDate, 'DD/MM/YYYY')) = REP_DATE

is causing the issue. when you use to_date without the time format, oracle will use the current sessions NLS format to convert, which in your case might not be "DD/MM/YYYY". Check this...

SQL> select sysdate from dual;

SYSDATE
---------
26-SEP-12

Which means my session's setting is DD-Mon-YY

SQL> select to_char(sysdate,'MM/DD/YYYY') from dual;

TO_CHAR(SY
----------
09/26/2012


SQL> select to_date(to_char(sysdate,'MM/DD/YYYY')) from dual;
select to_date(to_char(sysdate,'MM/DD/YYYY')) from dual
               *
ERROR at line 1:
ORA-01843: not a valid month

SQL> select to_date(to_char(sysdate,'MM/DD/YYYY'),'MM/DD/YYYY') from dual;

TO_DATE(T
---------
26-SEP-12

2.

More importantly, Why are you converting to char and then to date, instead of directly comparing

MaxDate = REP_DATE

If you want to ignore the time component in MaxDate before comparision, you should use..

trunc(MaxDate ) = rep_date

instead.

==Update : based on updated question.

Rep_Date = 01/04/2009 Rep_Time = 01/01/1753 13:00:00

I think the problem is more complex. if rep_time is intended to be only time, then you cannot store it in the database as a date. It would have to be a string or date to time interval or numerically as seconds (thanks to Alex, see this) . If possible, I would suggest using one column rep_date that has both the date and time and compare it to the max date column directly.

If it is a running system and you have no control over repdate, you could try this.

trunc(rep_date) = trunc(maxdate) and 
to_char(rep_date,'HH24:MI:SS') = to_char(maxdate,'HH24:MI:SS')

Either way, the time is being stored incorrectly (as you can tell from the year 1753) and there could be other issues going forward.

How to get everything after a certain character?

Here is the method by using explode:

$text = explode('_', '233718_This_is_a_string', 2)[1]; // Returns This_is_a_string

or:

$text = @end((explode('_', '233718_This_is_a_string', 2)));

By specifying 2 for the limit parameter in explode(), it returns array with 2 maximum elements separated by the string delimiter. Returning 2nd element ([1]), will give the rest of string.


Here is another one-liner by using strpos (as suggested by @flu):

$needle = '233718_This_is_a_string';
$text = substr($needle, (strpos($needle, '_') ?: -1) + 1); // Returns This_is_a_string

When to use RabbitMQ over Kafka?

RabbitMQ is a traditional general purpose message broker. It enables web servers to respond to requests quickly and deliver messages to multiple services. Publishers are able to publish messages and make them available to queues, so that consumers can retrieve them. The communication can be either asynchronous or synchronous.


On the other hand, Apache Kafka is not just a message broker. It was initially designed and implemented by LinkedIn in order to serve as a message queue. Since 2011, Kafka has been open sourced and quickly evolved into a distributed streaming platform, which is used for the implementation of real-time data pipelines and streaming applications.

It is horizontally scalable, fault-tolerant, wicked fast, and runs in production in thousands of companies.

Modern organisations have various data pipelines that facilitate the communication between systems or services. Things get a bit more complicated when a reasonable number of services needs to communicate with each other at real time.

The architecture becomes complex since various integrations are required in order to enable the inter-communication of these services. More precisely, for an architecture that encompasses m source and n target services, n x m distinct integrations need to be written. Also, every integration comes with a different specification, meaning that one might require a different protocol (HTTP, TCP, JDBC, etc.) or a different data representation (Binary, Apache Avro, JSON, etc.), making things even more challenging. Furthermore, source services might address increased load from connections that could potentially impact latency.

Apache Kafka leads to more simple and manageable architectures, by decoupling data pipelines. Kafka acts as a high-throughput distributed system where source services push streams of data, making them available for target services to pull them at real-time.

Also, a lot of open-source and enterprise-level User Interfaces for managing Kafka Clusters are available now. For more details refer to my articles Overview of UI monitoring tools for Apache Kafka clusters and Why Apache Kafka?


The decision of whether to go for RabbitMQ or Kafka is dependent to the requirements of your project. In general, if you want a simple/traditional pub-sub message broker then go for RabbitMQ. If you want to build an event-driven architecture on top of which your organisation will be acting on events at real-time, then go for Apache Kafka as it provides more functionality for this architectural type (for example Kafka Streams or ksqlDB).

cin and getline skipping input

The structure of your menu code is the issue:

cin >> choice;   // new line character is left in the stream

 switch ( ... ) {
     // We enter the handlers, '\n' still in the stream
 }

cin.ignore();   // Put this right after cin >> choice, before you go on
                // getting input with getline.

How to update core-js to core-js@3 dependency?

For npm

 npm install --save core-js@^3

for yarn

yarn add core-js@^3

Java Convert GMT/UTC to Local time doesn't work as expected

I also recommend using Joda as mentioned before.

Solving your problem using standard Java Date objects only can be done as follows:

    // **** YOUR CODE **** BEGIN ****
    long ts = System.currentTimeMillis();
    Date localTime = new Date(ts);
    String format = "yyyy/MM/dd HH:mm:ss";
    SimpleDateFormat sdf = new SimpleDateFormat(format);

    // Convert Local Time to UTC (Works Fine)
    sdf.setTimeZone(TimeZone.getTimeZone("UTC"));
    Date gmtTime = new Date(sdf.format(localTime));
    System.out.println("Local:" + localTime.toString() + "," + localTime.getTime() + " --> UTC time:"
            + gmtTime.toString() + "," + gmtTime.getTime());

    // **** YOUR CODE **** END ****

    // Convert UTC to Local Time
    Date fromGmt = new Date(gmtTime.getTime() + TimeZone.getDefault().getOffset(localTime.getTime()));
    System.out.println("UTC time:" + gmtTime.toString() + "," + gmtTime.getTime() + " --> Local:"
            + fromGmt.toString() + "-" + fromGmt.getTime());

Output:

Local:Tue Oct 15 12:19:40 CEST 2013,1381832380522 --> UTC time:Tue Oct 15 10:19:40 CEST 2013,1381825180000
UTC time:Tue Oct 15 10:19:40 CEST 2013,1381825180000 --> Local:Tue Oct 15 12:19:40 CEST 2013-1381832380000

A generic list of anonymous class

I guess

List<T> CreateEmptyGenericList<T>(T example) {
    return new List<T>();
}

void something() {
    var o = new { Id = 1, Name = "foo" };
    var emptyListOfAnonymousType = CreateEmptyGenericList(o);
}

will work.

You might also consider writing it like this:

void something() {
    var String = string.Emtpy;
    var Integer = int.MinValue;
    var emptyListOfAnonymousType = CreateEmptyGenericList(new { Id = Integer, Name = String });
}

How to pass form input value to php function

No, the action should be the name of php file. With on click you may only call JavaScript. And please be aware the hiding your code from the user undermines trust. JS runs on the browser so some trust is needed.

Working with UTF-8 encoding in Python source

In the source header you can declare:

#!/usr/bin/env python
# -*- coding: utf-8 -*-
....

It is described in the PEP 0263:

Then you can use UTF-8 in strings:

#!/usr/bin/env python
# -*- coding: utf-8 -*-

u = 'idzie waz waska drózka'
uu = u.decode('utf8')
s = uu.encode('cp1250')
print(s)

This declaration is not needed in Python 3 as UTF-8 is the default source encoding (see PEP 3120).

In addition, it may be worth verifying that your text editor properly encodes your code in UTF-8. Otherwise, you may have invisible characters that are not interpreted as UTF-8.

Hide Button After Click (With Existing Form on Page)

This is my solution. I Hide and then confirm check

onclick="return ConfirmSubmit(this);" />

function ConfirmSubmit(sender)
    {
        sender.disabled = true;
        var displayValue = sender.style.
        sender.style.display = 'none'

        if (confirm('Seguro que desea entregar los paquetes?')) {
            sender.disabled = false
            return true;
        }

        sender.disabled = false;
        sender.style.display = displayValue;
        return false;
    }

postgres: upgrade a user to be a superuser?

ALTER USER myuser WITH SUPERUSER;

You can read more at the Documentation

How to amend a commit without changing commit message (reusing the previous one)?

git commit -C HEAD --amend will do what you want. The -C option takes the metadata from another commit.

Install Qt on Ubuntu

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

How to specify jdk path in eclipse.ini on windows 8 when path contains space

I was facing the same issue but was unable to solve, until I try this:

  1. Please make sure you put -vm
  2. Then press Enter
  3. And then paste C:\Program Files\Java\jdk1.6.0_07\bin\javaw.exe

POST data to a URL in PHP

cURL-less you can use in php5

$url = 'URL';
$data = array('field1' => 'value', 'field2' => 'value');
$options = array(
        'http' => array(
        'header'  => "Content-type: application/x-www-form-urlencoded\r\n",
        'method'  => 'POST',
        'content' => http_build_query($data),
    )
);

$context  = stream_context_create($options);
$result = file_get_contents($url, false, $context);
var_dump($result);

Getting HTML elements by their attribute names

In jQuery this is so:

$("span['property'=v:name]"); // for selecting your span element

VB.Net .Clear() or txtbox.Text = "" textbox clear methods

Specifically if you want to clear your text box in VB.NET or VB 6.0, write this code:

TextBox1.Items.Clear()

If you are using VBA, then the use this code :

TextBox1.Text = "" or TextBox1.Clear()

Remove trailing zeros from decimal in SQL Server

Cast(20.5500 as Decimal(6,2))

should do it.

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

getClientRects return the client rects like this and if you want to get the lines, use the follow function like this

function getRowRects(element) {
    var rects = [],
        clientRects = element.getClientRects(),
        len = clientRects.length,
        clientRect, top, rectsLen, rect, i;

    for(i=0; i<len; i++) {
        has = false;
        rectsLen = rects.length;
        clientRect = clientRects[i];
        top = clientRect.top;
        while(rectsLen--) {
            rect = rects[rectsLen];
            if (rect.top == top) {
                has = true;
                break;
            }
        }
        if(has) {
            rect.right = rect.right > clientRect.right ? rect.right : clientRect.right;
            rect.width = rect.right - rect.left;
        }
        else {
            rects.push({
                top: clientRect.top,
                right: clientRect.right,
                bottom: clientRect.bottom,
                left: clientRect.left,
                width: clientRect.width,
                height: clientRect.height
            });
        }
    }
    return rects;
}

Android SDK folder taking a lot of disk space. Do we need to keep all of the System Images?

By deleting all emulator, sometime memory will not be reduce to our expectation. So open below mention path in you c drive

C:\Users{Username}.android\avd

In this avd folder, you can able to see all the avd's which you created earlier. So you need to delete all avd's that will remove all the unused spaces grab by your emulator's. Than create the fresh emulator for you works.

Changing Underline color

Problem with border-bottom is the extra distance between the text and the line. Problem with text-decoration-color is lack of browser support. Therefore my solution is the use of a background-image with a line. This supports any markup, color(s) and style of the line. top (12px in my example) is dependent on line-height of your text.

 u {
    text-decoration: none;
    background: transparent url(blackline.png) repeat-x 0px 12px;
}

How do I send email with JavaScript without opening the mail client?

You cannot cause the user's browser to send email silently. That would be a horrible security problem as any website could use their system as a spam relay and/or harvest their email address.

You need to make an HTTP request to a server side process (written in the language of your choice) which sends the mail from your server.

How to while loop until the end of a file in Python without checking for empty line?

I discovered while following the above suggestions that for line in f: does not work for a pandas dataframe (not that anyone said it would) because the end of file in a dataframe is the last column, not the last row. for example if you have a data frame with 3 fields (columns) and 9 records (rows), the for loop will stop after the 3rd iteration, not after the 9th iteration. Teresa

Scala list concatenation, ::: vs ++

Legacy. List was originally defined to be functional-languages-looking:

1 :: 2 :: Nil // a list
list1 ::: list2  // concatenation of two lists

list match {
  case head :: tail => "non-empty"
  case Nil          => "empty"
}

Of course, Scala evolved other collections, in an ad-hoc manner. When 2.8 came out, the collections were redesigned for maximum code reuse and consistent API, so that you can use ++ to concatenate any two collections -- and even iterators. List, however, got to keep its original operators, aside from one or two which got deprecated.

Stored Procedure parameter default value - is this a constant or a variable

It has to be a constant - the value has to be computable at the time that the procedure is created, and that one computation has to provide the value that will always be used.

Look at the definition of sys.all_parameters:

default_value sql_variant If has_default_value is 1, the value of this column is the value of the default for the parameter; otherwise, NULL.

That is, whatever the default for a parameter is, it has to fit in that column.


As Alex K pointed out in the comments, you can just do:

CREATE PROCEDURE [dbo].[problemParam] 
    @StartDate INT = NULL,
    @EndDate INT = NULL
AS  
BEGIN
   SET @StartDate = COALESCE(@StartDate,CONVERT(INT,(CONVERT(CHAR(8),GETDATE()-130,112))))

provided that NULL isn't intended to be a valid value for @StartDate.


As to the blog post you linked to in the comments - that's talking about a very specific context - that, the result of evaluating GETDATE() within the context of a single query is often considered to be constant. I don't know of many people (unlike the blog author) who would consider a separate expression inside a UDF to be part of the same query as the query that calls the UDF.

Remove a modified file from pull request

A pull request is just that: a request to merge one branch into another.

Your pull request doesn't "contain" anything, it's just a marker saying "please merge this branch into that one".

The set of changes the PR shows in the web UI is just the changes between the target branch and your feature branch. To modify your pull request, you must modify your feature branch, probably with a force push to the feature branch.

In your case, you'll probably want to amend your commit. Not sure about your exact situation, but some combination of interactive rebase and add -p should sort you out.

How to kill a child process by the parent process?

Send a SIGTERM or a SIGKILL to it:

http://en.wikipedia.org/wiki/SIGKILL

http://en.wikipedia.org/wiki/SIGTERM

SIGTERM is polite and lets the process clean up before it goes, whereas, SIGKILL is for when it won't listen >:)

Example from the shell (man page: http://unixhelp.ed.ac.uk/CGI/man-cgi?kill )

kill -9 pid

In C, you can do the same thing using the kill syscall:

kill(pid, SIGKILL);

See the following man page: http://linux.die.net/man/2/kill

Copy file(s) from one project to another using post build event...VS2010

xcopy "$(ProjectDir)Views\Home\Index.cshtml" "$(SolutionDir)MEFMVCPOC\Views\Home"

and if you want to copy entire folders:

xcopy /E /Y "$(ProjectDir)Views" "$(SolutionDir)MEFMVCPOC\Views"

Update: here's the working version

xcopy "$(ProjectDir)Views\ModuleAHome\Index.cshtml" "$(SolutionDir)MEFMVCPOC\Views\ModuleAHome\" /Y /I

Here are some commonly used switches with xcopy:

  • /I - treat as a directory if copying multiple files.
  • /Q - Do not display the files being copied.
  • /S - Copy subdirectories unless empty.
  • /E - Copy empty subdirectories.
  • /Y - Do not prompt for overwrite of existing files.
  • /R - Overwrite read-only files.

Create a batch file to copy and rename file

type C:\temp\test.bat>C:\temp\test.log

Integer to hex string in C++

You can try the following. It's working...

#include <iostream>
#include <fstream>
#include <string>
#include <sstream>
using namespace std;

template <class T>
string to_string(T t, ios_base & (*f)(ios_base&))
{
  ostringstream oss;
  oss << f << t;
  return oss.str();
}

int main ()
{
  cout<<to_string<long>(123456, hex)<<endl;
  system("PAUSE");
  return 0;
}

ClientScript.RegisterClientScriptBlock?

See if the below helps you:

I was using the following earlier:

ClientScript.RegisterClientScriptBlock(Page.GetType(), "AlertMsg", "<script language='javascript'>alert('The Web Policy need to be accepted to submit the new assessor information.');</script>");

After implementing AJAX in this page, it stopped working. After reading your blog, I changed the above to:

ScriptManager.RegisterClientScriptBlock(imgBtnSubmit, this.GetType(), "AlertMsg", "<script language='javascript'>alert('The Web Policy need to be accepted to submit the new assessor information.');</script>", false);

This is working perfectly fine.

(It’s .NET 2.0 Framework, I am using)

XXHDPI and XXXHDPI dimensions in dp for images and icons in android

try like this. hope it works

drawable-sw720dp-xxhdpi and values-sw720dp-xxhdpi

drawable-sw720dp-xxxhdpi and values-sw720dp-xxxhdpi

link might destroy so pasted ans

reference Android xxx-hdpi real devices

xxxhdpi was only introduced because of the way that launcher icons are scaled on the nexus 5's launcher Because the nexus 5's default launcher uses bigger icons, xxxhdpi was introduced so that icons would still look good on the nexus 5's launcher.

also check these links

Different resolution support android

Application Skeleton to support multiple screen

Is there a list of screen resolutions for all Android based phones and tablets?

Unable to find the requested .Net Framework Data Provider. It may not be installed. - when following mvc3 asp.net tutorial

This happened to me because I created a new project which was trying to use System.Web.Providers DefaultMembershipProvider for membership. My DB and application was set up to use System.Web.Security.SqlMembershipProvider instead. I had to update the provider and connection string (since this provider seems to have some weird connection string requirements) to get it working.

TypeError: Router.use() requires middleware function but got a Object

I was getting the same error message but had a different issue. Posting for others that are stuck on same.

I ported the get, post, put, delete functions to new router file while refactoring, and forgot to edit the paths. Example:

Incorrect:

//server.js
app.use('/blog-posts', blogPostsRouter);

//routers/blogPostsRouter.js
router.get('/blog-posts', (req, res) => {
  res.json(BlogPosts.get());
});

Correct:

//server.js
app.use('/blog-posts', blogPostsRouter);

//routers/blogPostsRouter.js
router.get('/', (req, res) => {
  res.json(BlogPosts.get());
});

Took a while to spot, as the error had me checking syntax where I might have been wrapping an argument in an object or where I missed the module.exports = router;

Not able to start Genymotion device

VMs used to work for me under Genymotion 2.0.0. with default RAM and CPU settings and VirtualBox 4.3.2 (on ubuntu 13.10). Upgrading to 2.0.1 made them stop working and give the error you mentioned.

I tried various fixes as I described here: https://stackoverflow.com/a/20018833/2527118, but in summary what fixed my problem was to delete VM and recreate it (same source and settings) in GenyMotion. You might want to try the other fixes (less destructive) before doing that.

Andrei

Increasing the Command Timeout for SQL command

Since it takes 2 mins to respond, you can increase the timeout to 3 mins by adding the below code

scGetruntotals.CommandTimeout = 180;

Note : the parameter value is in seconds.

What is a quick way to force CRLF in C# / .NET?

string nonNormalized = "\r\n\n\r";

string normalized = nonNormalized.Replace("\r", "\n").Replace("\n", "\r\n");

Equivalent of waitForVisible/waitForElementPresent in Selenium WebDriver tests using Java?

For individual element the code below could be used:

private boolean isElementPresent(By by) {
        try {
            driver.findElement(by);
            return true;
        } catch (NoSuchElementException e) {
            return false;
        }
    }
for (int second = 0;; second++) {
            if (second >= 60){
                fail("timeout");
            }
            try {
                if (isElementPresent(By.id("someid"))){
                    break;
                }
                }
            catch (Exception e) {

            }
            Thread.sleep(1000);
        }

Signing a Windows EXE file

And yet another option, if you're developing on Windows 10 but don't have Microsoft's signtool.exe installed, you can use Bash on Ubuntu on Windows to sign your app. Here is a run down:

https://blog.synapp.nz/2017/06/16/code-signing-a-windows-application-on-linux-on-windows/

Getting the base url of the website and globally passing it to twig in Symfony 2

 <base href="{{ app.request.getSchemeAndHttpHost() }}"/>

or from controller

$this->container->get('router')->getContext()->getSchemeAndHttpHost()

Move to another EditText when Soft Keyboard Next is clicked on Android

In Kotlin I have used Bellow like..

  1. xml:

    <EditText
      android:id="@+id/et_amount"
      android:layout_width="match_parent"
      android:layout_height="wrap_content"
      android:imeOptions="actionNext"
      android:inputType="number"
      android:singleLine="true" />
    
  2. in kotlin:

    et_amount.setOnEditorActionListener { v, actionId, event ->
    
        if (actionId == EditorInfo.IME_ACTION_NEXT) {
            // do some code
            true
        } else {
            false
        }
    }
    

How do I print a list of "Build Settings" in Xcode project?

In Xcode 4 and possibly before, in the run script build phase there is an option "Show enviroment variables in build phase". If selected this will show then on a olive green background in the build log.

Create a hexadecimal colour based on a string with JavaScript

I convert this for Java.

Tanks for all.

public static int getColorFromText(String text)
    {
        if(text == null || text.length() < 1)
            return Color.BLACK;

        int hash = 0;

        for (int i = 0; i < text.length(); i++)
        {
            hash = text.charAt(i) + ((hash << 5) - hash);
        }

        int c = (hash & 0x00FFFFFF);
        c = c - 16777216;

        return c;
    }

Getting rid of bullet points from <ul>

Put

<style type="text/css">
 ul#otis {
     list-style-type: none;
   }
</style>

immediately before the list to test it out. Or

<ul style="list-style-type: none;">

C# refresh DataGridView when updating or inserted on another form

putting a quick example, should be a sufficient starting point

Code in Form A

public event EventHandler<EventArgs> RowAdded;

private void btnRowAdded_Click(object sender, EventArgs e)
{
     // insert data
     // if successful raise event
     OnRowAddedEvent();
}

private void OnRowAddedEvent()
{
     var listener = RowAdded;
     if (listener != null)
         listener(this, EventArgs.Empty);
}

Code in Form B

private void button1_Click(object sender, EventArgs e)
{
     var frm = new Form2();
     frm.RowAdded += new EventHandler<EventArgs>(frm_RowAdded);
     frm.Show();
}

void frm_RowAdded(object sender, EventArgs e)
{
     // retrieve data again
}

You can even consider creating your own EventArgs class that can contain the newly added data. You can then use this to directly add the data to a new row in DatagridView

libstdc++.so.6: cannot open shared object file: No such file or directory

/usr/local/cilk/bin/../lib32/pinbin is dynamically linked to a library libstdc++.so.6 which is not present anymore. You need to recompile Cilk

how to use free cloud database with android app?

As Wingman said, Google App Engine is a great solution for your scenario.

You can get some information about GAE+Android here: https://developers.google.com/eclipse/docs/appengine_connected_android

And from this Google IO 2012 session: http://www.youtube.com/watch?v=NU_wNR_UUn4

What's the best way to dedupe a table?

Ran into the problem today, none of the existing answers helped me. Assume you want to deduplicate your table named your_table.

Step 1: Create a new table with deduped values

If borrowed this code from somewhere else on StackOverflow but can't seem to find it again. It works fine against PostgreSQL. It creates a table your_table_deduped where (col1, col2) are unique.

CREATE TABLE your_table_deduped AS
SELECT * FROM your_table WHERE ctid NOT IN
(SELECT ctid FROM
  (SELECT ctid, ROW_NUMBER() OVER
    (PARTITION BY col1, col2 ORDER BY ctid) AS rnum
  FROM your_table) t
WHERE t.rnum > 1);

Step 2: Replace your first table with the deduped copy

We only delete the values in this step, because it allows us to keep the indexes, constraints, etc. in your table.

DELETE FROM your_table;
INSERT INTO your_table
SELECT * FROM your_table_deduped;

Step 3: Delete the deduped copy

DROP TABLE site_daily_kpis_dedup;

And voila, you have deduplicated your table!

Regex pattern inside SQL Replace function?

i think this solution is faster and simple. i use always CTE/recursive beacuse WHILE is so slow on mssql. I use it in projects I work with and large databases.

/*
Function:           dbo.kSql_ReplaceRegExp
Create Date:        20.02.2021
Author:             Karcan Ozbal

Description:        The given string value will be replaced according to the given regexp/pattern.

Parameter(s):       @Value       : Value/Text to REPLACE.
                    @RegExp      : The regexp/pattern to be used for REPLACE operation.

Usage:              select dbo.kSql_ReplaceRegExp('2T3EST5','%[0-9]%')
Output:             'TEST'
*/
ALTER FUNCTION [dbo].[kSql_ReplaceRegExp](
    @Value nvarchar(max),
    @RegExp nvarchar(50)
)
RETURNS nvarchar(max)
AS
BEGIN
    DECLARE @Result nvarchar(max)

    ;WITH CTE AS (
        SELECT NUM = 1, VALUE = @Value, IDX = PATINDEX(@RegExp, @Value)
        UNION ALL
        SELECT NUM + 1, VALUE = REPLACE(VALUE, SUBSTRING(VALUE,IDX,1),''), IDX = PATINDEX(@RegExp, REPLACE(VALUE, SUBSTRING(VALUE,IDX,1),'')) 
        FROM CTE
        WHERE IDX > 0
    )
    SELECT TOP(1) @Result = VALUE 
    FROM CTE 
    ORDER BY NUM DESC
    OPTION (maxrecursion 0)

    RETURN @Result
END

See changes to a specific file using git

You can execute

git status -s

This will show modified files name and then by copying the interested file path you can see changes using git diff

git diff <filepath + filename>

Set the layout weight of a TextView programmatically

You have to use TableLayout.LayoutParams with something like this:

TextView tv = new TextView(v.getContext());
tv.setLayoutParams(new TableLayout.LayoutParams(LayoutParams.WRAP_CONTENT, LayoutParams.WRAP_CONTENT, 1f));

The last parameter is the weight.

When and how should I use a ThreadLocal variable?

There is very good example in book Java Concurrency in Practice. Where author (Joshua Bloch) explains how Thread confinement is one of the simplest ways to achieve thread safety and ThreadLocal is more formal means of maintaining thread confinement. In the end he also explain how people can abuse it by using it as global variables.

I have copied the text from the mentioned book but code 3.10 is missing as it is not much important to understand where ThreadLocal should be use.

Thread-local variables are often used to prevent sharing in designs based on mutable Singletons or global variables. For example, a single-threaded application might maintain a global database connection that is initialized at startup to avoid having to pass a Connection to every method. Since JDBC connections may not be thread-safe, a multithreaded application that uses a global connection without additional coordination is not thread-safe either. By using a ThreadLocal to store the JDBC connection, as in ConnectionHolder in Listing 3.10, each thread will have its own connection.

ThreadLocal is widely used in implementing application frameworks. For example, J2EE containers associate a transaction context with an executing thread for the duration of an EJB call. This is easily implemented using a static Thread-Local holding the transaction context: when framework code needs to determine what transaction is currently running, it fetches the transaction context from this ThreadLocal. This is convenient in that it reduces the need to pass execution context information into every method, but couples any code that uses this mechanism to the framework.

It is easy to abuse ThreadLocal by treating its thread confinement property as a license to use global variables or as a means of creating “hidden” method arguments. Like global variables, thread-local variables can detract from reusability and introduce hidden couplings among classes, and should therefore be used with care.

Difference between UTF-8 and UTF-16?

Simple way to differentiate UTF-8 and UTF-16 is to identify commonalities between them.

Other than sharing same unicode number for given character, each one is their own format.

UTF-8 try to represent, every unicode number given to character with one byte(If it is ASCII), else 2 two bytes, else 4 bytes and so on...

UTF-16 try to represent, every unicode number given to character with two byte to start with. If two bytes are not sufficient, then uses 4 bytes. IF that is also not sufficient, then uses 6 bytes.

Theoretically, UTF-16 is more space efficient, but in practical UTF-8 is more space efficient as most of the characters(98% of data) for processing are ASCII and UTF-8 try to represent them with single byte and UTF-16 try to represent them with 2 bytes.

Also, UTF-8 is superset of ASCII encoding. So every app that expects ASCII data would also accepted by UTF-8 processor. This is not true for UTF-16. UTF-16 could not understand ASCII, and this is big hurdle for UTF-16 adoption.

Another point to note is, all UNICODE as of now could be fit in 4 bytes of UTF-8 maximum(Considering all languages of world). This is same as UTF-16 and no real saving in space compared to UTF-8 ( https://stackoverflow.com/a/8505038/3343801 )

So, people use UTF-8 where ever possible.

How to quickly drop a user with existing privileges

There is no REVOKE ALL PRIVILEGES ON ALL VIEWS, so I ended with:

do $$
DECLARE r record;
begin
  for r in select * from pg_views where schemaname = 'myschem'
  loop
    execute 'revoke all on ' || quote_ident(r.schemaname) ||'.'|| quote_ident(r.viewname) || ' from "XUSER"';
  end loop;
end $$;

and usual:

REVOKE ALL PRIVILEGES ON DATABASE mydb FROM "XUSER";
REVOKE ALL PRIVILEGES ON SCHEMA myschem FROM "XUSER";
REVOKE ALL PRIVILEGES ON ALL TABLES IN SCHEMA myschem FROM "XUSER";
REVOKE ALL PRIVILEGES ON ALL SEQUENCES IN SCHEMA myschem FROM "XUSER";
REVOKE ALL PRIVILEGES ON ALL FUNCTIONS IN SCHEMA myschem FROM "XUSER";

for the following to succeed:

drop role "XUSER";

SASS - use variables across multiple files

This answer shows how I ended up using this and the additional pitfalls I hit.

I made a master SCSS file. This file must have an underscore at the beginning for it to be imported:

// assets/_master.scss 
$accent: #6D87A7;           
$error: #811702;

Then, in the header of all of my other .SCSS files, I import the master:

// When importing the master, you leave out the underscore, and it
// will look for a file with the underscore. This prevents the SCSS
// compiler from generating a CSS file from it.
@import "assets/master";

// Then do the rest of my CSS afterwards:
.text { color: $accent; }

IMPORTANT

Do not include anything but variables, function declarations and other SASS features in your _master.scss file. If you include actual CSS, it will duplicate this CSS across every file you import the master into.

What is the default maximum heap size for Sun's JVM from Java SE 6?

With JDK, You can also use jinfo to connect to the JVM for the <PROCESS_ID> in question and get the value for MaxHeapSize:

jinfo -flag MaxHeapSize <PROCESS_ID>

How to develop a soft keyboard for Android?

Create Custom Key Board for Own EditText

Download Entire Code

In this post i Created Simple Keyboard which contains Some special keys like ( France keys ) and it's supported Capital letters and small letters and Number keys and some Symbols .

package sra.keyboard;

import android.app.Activity;
import android.os.Bundle;
import android.util.Log;
import android.view.MotionEvent;
import android.view.View;
import android.view.WindowManager;
import android.view.View.OnClickListener;
import android.view.View.OnFocusChangeListener;
import android.view.View.OnTouchListener;
import android.widget.Button;
import android.widget.EditText;
import android.widget.RelativeLayout;

public class Main extends Activity implements OnTouchListener, OnClickListener,
  OnFocusChangeListener {
 private EditText mEt, mEt1; // Edit Text boxes
 private Button mBSpace, mBdone, mBack, mBChange, mNum;
 private RelativeLayout mLayout, mKLayout;
 private boolean isEdit = false, isEdit1 = false;
 private String mUpper = "upper", mLower = "lower";
 private int w, mWindowWidth;
 private String sL[] = { "a", "b", "c", "d", "e", "f", "g", "h", "i", "j",
   "k", "l", "m", "n", "o", "p", "q", "r", "s", "t", "u", "v", "w",
   "x", "y", "z", "ç", "à", "é", "è", "û", "î" };
 private String cL[] = { "A", "B", "C", "D", "E", "F", "G", "H", "I", "J",
   "K", "L", "M", "N", "O", "P", "Q", "R", "S", "T", "U", "V", "W",
   "X", "Y", "Z", "ç", "à", "é", "è", "û", "î" };
 private String nS[] = { "!", ")", "'", "#", "3", "$", "%", "&", "8", "*",
   "?", "/", "+", "-", "9", "0", "1", "4", "@", "5", "7", "(", "2",
   "\"", "6", "_", "=", "]", "[", "<", ">", "|" };
 private Button mB[] = new Button[32];

 @Override
 public void onCreate(Bundle savedInstanceState) {
  super.onCreate(savedInstanceState);
  try {
   setContentView(R.layout.main);
   // adjusting key regarding window sizes
   setKeys();
   setFrow();
   setSrow();
   setTrow();
   setForow();
   mEt = (EditText) findViewById(R.id.xEt);
   mEt.setOnTouchListener(this);
   mEt.setOnFocusChangeListener(this);
   mEt1 = (EditText) findViewById(R.id.et1);

   mEt1.setOnTouchListener(this);
   mEt1.setOnFocusChangeListener(this);
   mEt.setOnClickListener(this);
   mEt1.setOnClickListener(this);
   mLayout = (RelativeLayout) findViewById(R.id.xK1);
   mKLayout = (RelativeLayout) findViewById(R.id.xKeyBoard);

  } catch (Exception e) {
   Log.w(getClass().getName(), e.toString());
  }

 }

 @Override
 public boolean onTouch(View v, MotionEvent event) {
  if (v == mEt) {
   hideDefaultKeyboard();
   enableKeyboard();

  }
  if (v == mEt1) {
   hideDefaultKeyboard();
   enableKeyboard();

  }
  return true;
 }

 @Override
 public void onClick(View v) {

  if (v == mBChange) {

   if (mBChange.getTag().equals(mUpper)) {
    changeSmallLetters();
    changeSmallTags();
   } else if (mBChange.getTag().equals(mLower)) {
    changeCapitalLetters();
    changeCapitalTags();
   }

  } else if (v != mBdone && v != mBack && v != mBChange && v != mNum) {
   addText(v);

  } else if (v == mBdone) {

   disableKeyboard();

  } else if (v == mBack) {
   isBack(v);
  } else if (v == mNum) {
   String nTag = (String) mNum.getTag();
   if (nTag.equals("num")) {
    changeSyNuLetters();
    changeSyNuTags();
    mBChange.setVisibility(Button.INVISIBLE);

   }
   if (nTag.equals("ABC")) {
    changeCapitalLetters();
    changeCapitalTags();
   }

  }

 }

 @Override
 public void onFocusChange(View v, boolean hasFocus) {
  if (v == mEt && hasFocus == true) {
   isEdit = true;
   isEdit1 = false;

  } else if (v == mEt1 && hasFocus == true) {
   isEdit = false;
   isEdit1 = true;

  }

 }

 private void addText(View v) {
  if (isEdit == true) {
   String b = "";
   b = (String) v.getTag();
   if (b != null) {
    // adding text in Edittext
    mEt.append(b);

   }
  }

  if (isEdit1 == true) {
   String b = "";
   b = (String) v.getTag();
   if (b != null) {
    // adding text in Edittext
    mEt1.append(b);

   }

  }

 }

 private void isBack(View v) {
  if (isEdit == true) {
   CharSequence cc = mEt.getText();
   if (cc != null && cc.length() > 0) {
    {
     mEt.setText("");
     mEt.append(cc.subSequence(0, cc.length() - 1));
    }

   }
  }

  if (isEdit1 == true) {
   CharSequence cc = mEt1.getText();
   if (cc != null && cc.length() > 0) {
    {
     mEt1.setText("");
     mEt1.append(cc.subSequence(0, cc.length() - 1));
    }
   }
  }
 }
 private void changeSmallLetters() {
  mBChange.setVisibility(Button.VISIBLE);
  for (int i = 0; i < sL.length; i++)
   mB[i].setText(sL[i]);
  mNum.setTag("12#");
 }
 private void changeSmallTags() {
  for (int i = 0; i < sL.length; i++)
   mB[i].setTag(sL[i]);
  mBChange.setTag("lower");
  mNum.setTag("num");
 }
 private void changeCapitalLetters() {
  mBChange.setVisibility(Button.VISIBLE);
  for (int i = 0; i < cL.length; i++)
   mB[i].setText(cL[i]);
  mBChange.setTag("upper");
  mNum.setText("12#");

 }

 private void changeCapitalTags() {
  for (int i = 0; i < cL.length; i++)
   mB[i].setTag(cL[i]);
  mNum.setTag("num");

 }

 private void changeSyNuLetters() {

  for (int i = 0; i < nS.length; i++)
   mB[i].setText(nS[i]);
  mNum.setText("ABC");
 }

 private void changeSyNuTags() {
  for (int i = 0; i < nS.length; i++)
   mB[i].setTag(nS[i]);
  mNum.setTag("ABC");
 }

 // enabling customized keyboard
 private void enableKeyboard() {

  mLayout.setVisibility(RelativeLayout.VISIBLE);
  mKLayout.setVisibility(RelativeLayout.VISIBLE);

 }

 // Disable customized keyboard
 private void disableKeyboard() {
  mLayout.setVisibility(RelativeLayout.INVISIBLE);
  mKLayout.setVisibility(RelativeLayout.INVISIBLE);

 }

 private void hideDefaultKeyboard() {
  getWindow().setSoftInputMode(
    WindowManager.LayoutParams.SOFT_INPUT_STATE_ALWAYS_HIDDEN);

 }

 private void setFrow() {
  w = (mWindowWidth / 13);
  w = w - 15;
  mB[16].setWidth(w);
  mB[22].setWidth(w + 3);
  mB[4].setWidth(w);
  mB[17].setWidth(w);
  mB[19].setWidth(w);
  mB[24].setWidth(w);
  mB[20].setWidth(w);
  mB[8].setWidth(w);
  mB[14].setWidth(w);
  mB[15].setWidth(w);
  mB[16].setHeight(50);
  mB[22].setHeight(50);
  mB[4].setHeight(50);
  mB[17].setHeight(50);
  mB[19].setHeight(50);
  mB[24].setHeight(50);
  mB[20].setHeight(50);
  mB[8].setHeight(50);
  mB[14].setHeight(50);
  mB[15].setHeight(50);

 }

 private void setSrow() {
  w = (mWindowWidth / 10);
  mB[0].setWidth(w);
  mB[18].setWidth(w);
  mB[3].setWidth(w);
  mB[5].setWidth(w);
  mB[6].setWidth(w);
  mB[7].setWidth(w);
  mB[26].setWidth(w);
  mB[9].setWidth(w);
  mB[10].setWidth(w);
  mB[11].setWidth(w);
  mB[26].setWidth(w);

  mB[0].setHeight(50);
  mB[18].setHeight(50);
  mB[3].setHeight(50);
  mB[5].setHeight(50);
  mB[6].setHeight(50);
  mB[7].setHeight(50);
  mB[9].setHeight(50);
  mB[10].setHeight(50);
  mB[11].setHeight(50);
  mB[26].setHeight(50);
 }

 private void setTrow() {
  w = (mWindowWidth / 12);
  mB[25].setWidth(w);
  mB[23].setWidth(w);
  mB[2].setWidth(w);
  mB[21].setWidth(w);
  mB[1].setWidth(w);
  mB[13].setWidth(w);
  mB[12].setWidth(w);
  mB[27].setWidth(w);
  mB[28].setWidth(w);
  mBack.setWidth(w);

  mB[25].setHeight(50);
  mB[23].setHeight(50);
  mB[2].setHeight(50);
  mB[21].setHeight(50);
  mB[1].setHeight(50);
  mB[13].setHeight(50);
  mB[12].setHeight(50);
  mB[27].setHeight(50);
  mB[28].setHeight(50);
  mBack.setHeight(50);

 }

 private void setForow() {
  w = (mWindowWidth / 10);
  mBSpace.setWidth(w * 4);
  mBSpace.setHeight(50);
  mB[29].setWidth(w);
  mB[29].setHeight(50);

  mB[30].setWidth(w);
  mB[30].setHeight(50);

  mB[31].setHeight(50);
  mB[31].setWidth(w);
  mBdone.setWidth(w + (w / 1));
  mBdone.setHeight(50);

 }

 private void setKeys() {
  mWindowWidth = getWindowManager().getDefaultDisplay().getWidth(); // getting
  // window
  // height
  // getting ids from xml files
  mB[0] = (Button) findViewById(R.id.xA);
  mB[1] = (Button) findViewById(R.id.xB);
  mB[2] = (Button) findViewById(R.id.xC);
  mB[3] = (Button) findViewById(R.id.xD);
  mB[4] = (Button) findViewById(R.id.xE);
  mB[5] = (Button) findViewById(R.id.xF);
  mB[6] = (Button) findViewById(R.id.xG);
  mB[7] = (Button) findViewById(R.id.xH);
  mB[8] = (Button) findViewById(R.id.xI);
  mB[9] = (Button) findViewById(R.id.xJ);
  mB[10] = (Button) findViewById(R.id.xK);
  mB[11] = (Button) findViewById(R.id.xL);
  mB[12] = (Button) findViewById(R.id.xM);
  mB[13] = (Button) findViewById(R.id.xN);
  mB[14] = (Button) findViewById(R.id.xO);
  mB[15] = (Button) findViewById(R.id.xP);
  mB[16] = (Button) findViewById(R.id.xQ);
  mB[17] = (Button) findViewById(R.id.xR);
  mB[18] = (Button) findViewById(R.id.xS);
  mB[19] = (Button) findViewById(R.id.xT);
  mB[20] = (Button) findViewById(R.id.xU);
  mB[21] = (Button) findViewById(R.id.xV);
  mB[22] = (Button) findViewById(R.id.xW);
  mB[23] = (Button) findViewById(R.id.xX);
  mB[24] = (Button) findViewById(R.id.xY);
  mB[25] = (Button) findViewById(R.id.xZ);
  mB[26] = (Button) findViewById(R.id.xS1);
  mB[27] = (Button) findViewById(R.id.xS2);
  mB[28] = (Button) findViewById(R.id.xS3);
  mB[29] = (Button) findViewById(R.id.xS4);
  mB[30] = (Button) findViewById(R.id.xS5);
  mB[31] = (Button) findViewById(R.id.xS6);
  mBSpace = (Button) findViewById(R.id.xSpace);
  mBdone = (Button) findViewById(R.id.xDone);
  mBChange = (Button) findViewById(R.id.xChange);
  mBack = (Button) findViewById(R.id.xBack);
  mNum = (Button) findViewById(R.id.xNum);
  for (int i = 0; i < mB.length; i++)
   mB[i].setOnClickListener(this);
  mBSpace.setOnClickListener(this);
  mBdone.setOnClickListener(this);
  mBack.setOnClickListener(this);
  mBChange.setOnClickListener(this);
  mNum.setOnClickListener(this);

 }

}

WAMP shows error 'MSVCR100.dll' is missing when install

  1. Uninstall WAMP

  2. Download Microsoft Visual C++ Redistributable Packages for Visual Studio 2012 Update 4 and Microsoft Visual C++ Redistributable for Visual Studio 2015, 2017 and 2019

    Microsoft Visual C++ Redistributable Packages for Visual Studio 2012 Update 4

    Microsoft Visual C++ Redistributable for Visual Studio 2015, 2017 and 2019 x86

    Microsoft Visual C++ Redistributable for Visual Studio 2015, 2017 and 2019 x64

  • Note :- Download both x86 and x64 versions if you are using 64 bit O/S
  1. Install both x86 and x64 versions of Visual C++ Redistributable Packages for Visual Studio 2012 Update 4 and Visual C++ Redistributable for Visual Studio 2015, 2017 and 2019

enter image description here

  1. Intsall WAMP again. That's it. All the problems will solve.

upstream sent too big header while reading response header from upstream

If nginx is running as a proxy / reverse proxy

that is, for users of ngx_http_proxy_module

In addition to fastcgi, the proxy module also saves the request header in a temporary buffer.

So you may need also to increase the proxy_buffer_size and the proxy_buffers, or disable it totally (Please read the nginx documentation).

Example of proxy buffering configuration

http {
  proxy_buffer_size   128k;
  proxy_buffers   4 256k;
  proxy_busy_buffers_size   256k;
}

Example of disabling your proxy buffer (recommended for long polling servers)

http {
  proxy_buffering off;
}

For more information: Nginx proxy module documentation

How to obtain the location of cacerts of the default java installation?

In MacOS Mojave, the location is:

/Library/Java/JavaVirtualMachines/jdk1.8.0_192.jdk/Contents/Home/jre/lib/security/cacerts 

If using sdkman to manage java versions, the cacerts is in

~/.sdkman/candidates/java/current/jre/lib/security

Plot two graphs in same plot in R

we can also use lattice library

library(lattice)
x <- seq(-2,2,0.05)
y1 <- pnorm(x)
y2 <- pnorm(x,1,1)
xyplot(y1 + y2 ~ x, ylab = "y1 and y2", type = "l", auto.key = list(points = FALSE,lines = TRUE))

For specific colors

xyplot(y1 + y2 ~ x,ylab = "y1 and y2", type = "l", auto.key = list(points = F,lines = T), par.settings = list(superpose.line = list(col = c("red","green"))))

enter image description here

How do I delete a local repository in git?

To piggyback on rkj's answer, to avoid endless prompts (and force the command recursively), enter the following into the command line, within the project folder:

$ rm -rf .git

Or to delete .gitignore and .gitmodules if any (via @aragaer):

$ rm -rf .git*

Then from the same ex-repository folder, to see if hidden folder .git is still there:

$ ls -lah

If it's not, then congratulations, you've deleted your local git repo, but not a remote one if you had it. You can delete GitHub repo on their site (github.com).

To view hidden folders in Finder (Mac OS X) execute these two commands in your terminal window:

defaults write com.apple.finder AppleShowAllFiles TRUE
killall Finder

Source: http://lifehacker.com/188892/show-hidden-files-in-finder.

Set up Python 3 build system with Sublime Text 3

If you are using PyQt, then for normal work, you should add "shell":"true" value, this looks like:

{
  "cmd": ["c:/Python32/python.exe", "-u", "$file"],
  "file_regex": "^[ ]*File \"(...*?)\", line ([0-9]*)",
  "selector": "source.python",
  "shell":"true"
}

How to Convert UTC Date To Local time Zone in MySql Select Query

 select convert_tz(now(),@@session.time_zone,'+05:30')

replace '+05:30' with desired timezone. see here - https://stackoverflow.com/a/3984412/2359994

to format into desired time format, eg:

 select DATE_FORMAT(convert_tz(now(),@@session.time_zone,'+05:30') ,'%b %d %Y %h:%i:%s %p') 

you will get similar to this -> Dec 17 2014 10:39:56 AM

MySQL show status - active or total connections?

You can also do

SHOW STATUS WHERE `variable_name` = 'Max_used_connections';

count of entries in data frame in R

You could use table:

R> x <- read.table(textConnection('
   Believe Age Gender Presents Behaviour
1    FALSE   9   male       25   naughty
2     TRUE   5   male       20      nice
3     TRUE   4 female       30      nice
4     TRUE   4   male       34   naughty'
), header=TRUE)

R> table(x$Believe)

FALSE  TRUE 
    1     3 

Change Circle color of radio button

@jh314 is correct. In AndroidManifest.xml,

 <application
    android:allowBackup="true"
    android:icon="@drawable/icon"
    android:label="@string/app_name"
    android:theme="@style/AppTheme"></application>

In style.xml

  <!-- Application theme. -->
<style name="AppTheme" parent="Theme.AppCompat.Light.NoActionBar">
    <item name="colorAccent">@color/red</item>
    <!-- All customizations that are NOT specific to a particular API-level can go here. -->
</style>

the item name must be colorAccent,it decides the application's widgets default color.

But if you want to change the color in code,Maybe @aknay's answer is correct.

How can I create a unique constraint on my column (SQL Server 2008 R2)?

Set column as unique in SQL Server from the GUI:

They really make you run around the barn to do it with the GUI:

Make sure your column does not violate the unique constraint before you begin.

  1. Open SQL Server Management Studio.
  2. Right click your Table, click "Design".
  3. Right click the column you want to edit, a popup menu appears, click Indexes/Keys.
  4. Click the "Add" Button.
  5. Expand the "General" tab.
  6. Make sure you have the column you want to make unique selected in the "columns" box.
  7. Change the "Type" box to "Unique Key".
  8. Click "Close".
  9. You see a little asterisk in the file window, this means changes are not yet saved.
  10. Press Save or hit Ctrl+s. It should save, and your column should be unique.

Or set column as unique from the SQL Query window:

alter table location_key drop constraint pinky;
alter table your_table add constraint pinky unique(yourcolumn);

Changes take effect immediately:

Command(s) completed successfully.

How do you hide the Address bar in Google Chrome for Chrome Apps?

enter image description here

in macOS make service by automator.

that's it. you can assign short cut.

Getting the computer name in Java

I agree with peterh's answer, so for those of you who like to copy and paste instead of 60 more seconds of Googling:

private String getComputerName()
{
    Map<String, String> env = System.getenv();
    if (env.containsKey("COMPUTERNAME"))
        return env.get("COMPUTERNAME");
    else if (env.containsKey("HOSTNAME"))
        return env.get("HOSTNAME");
    else
        return "Unknown Computer";
}

I have tested this in Windows 7 and it works. If peterh was right the else if should take care of Mac and Linux. Maybe someone can test this? You could also implement Brian Roach's answer inside the else if you wanted extra robustness.

Get index of array element faster than O(n)

Is there a good reason not to use a hash? Lookups are O(1) vs. O(n) for the array.

Group by in LINQ

Absolutely - you basically want:

var results = from p in persons
              group p.car by p.PersonId into g
              select new { PersonId = g.Key, Cars = g.ToList() };

Or as a non-query expression:

var results = persons.GroupBy(
    p => p.PersonId, 
    p => p.car,
    (key, g) => new { PersonId = key, Cars = g.ToList() });

Basically the contents of the group (when viewed as an IEnumerable<T>) is a sequence of whatever values were in the projection (p.car in this case) present for the given key.

For more on how GroupBy works, see my Edulinq post on the topic.

(I've renamed PersonID to PersonId in the above, to follow .NET naming conventions.)

Alternatively, you could use a Lookup:

var carsByPersonId = persons.ToLookup(p => p.PersonId, p => p.car);

You can then get the cars for each person very easily:

// This will be an empty sequence for any personId not in the lookup
var carsForPerson = carsByPersonId[personId];

Iterating over Typescript Map

Per the TypeScript 2.3 release notes on "New --downlevelIteration":

for..of statements, Array Destructuring, and Spread elements in Array, Call, and New expressions support Symbol.iterator in ES5/E3 if available when using --downlevelIteration

This is not enabled by default! Add "downlevelIteration": true to your tsconfig.json, or pass --downlevelIteration flag to tsc, to get full iterator support.

With this in place, you can write for (let keyval of myMap) {...} and keyval's type will be automatically inferred.


Why is this turned off by default? According to TypeScript contributor @aluanhaddad,

It is optional because it has a very significant impact on the size of generated code, and potentially on performance, for all uses of iterables (including arrays).

If you can target ES2015 ("target": "es2015" in tsconfig.json or tsc --target ES2015) or later, enabling downlevelIteration is a no-brainer, but if you're targeting ES5/ES3, you might benchmark to ensure iterator support doesn't impact performance (if it does, you might be better off with Array.from conversion or forEach or some other workaround).

Manually Set Value for FormBuilder Control

In Angular 2 Final (RC5+) there are new APIs for updating form values. The patchValue() API method supports partial form updates, where we only need to specify some of the fields:

this.form.patchValue({id: selected.id})

There is also the setValue() API method that needs an object with all the form fields. If there is a field missing, we will get an error.

jQuery add image inside of div tag

If we want to change the content of <div> tag whenever the function image()is called, we have to do like this:

Javascript

function image() {
    var img = document.createElement("IMG");
    img.src = "/images/img1.gif";
    $('#image').html(img); 
}

HTML

<div id="image"></div>
<div><a href="javascript:image();">First Image</a></div>

How to Set AllowOverride all

On Linux, in order to relax access to the document root, you should edit the following file:

/etc/httpd/conf/httpd.conf

And depending on what directory level you want to relax access to, you have to change the directive

AllowOverride None

to

AllowOverride All

So, assuming you want to allow access to files on the /var/www/html directory, you should change the following lines from:

<Directory "/var/www/html">
 AllowOverride None
</Directory>

to

<Directory "/var/www/html">
 AllowOverride All
</Directory>

Make XAMPP / Apache serve file outside of htdocs folder

Ok, per pix0r's, Sparks' and Dave's answers it looks like there are three ways to do this:


Virtual Hosts

  1. Open C:\xampp\apache\conf\extra\httpd-vhosts.conf.
  2. Un-comment ~line 19 (NameVirtualHost *:80).
  3. Add your virtual host (~line 36):

    <VirtualHost *:80>
        DocumentRoot C:\Projects\transitCalculator\trunk
        ServerName transitcalculator.localhost
        <Directory C:\Projects\transitCalculator\trunk>
            Order allow,deny
            Allow from all
        </Directory>
    </VirtualHost>
    
  4. Open your hosts file (C:\Windows\System32\drivers\etc\hosts).

  5. Add

    127.0.0.1 transitcalculator.localhost #transitCalculator
    

    to the end of the file (before the Spybot - Search & Destroy stuff if you have that installed).

  6. Save (You might have to save it to the desktop, change the permissions on the old hosts file (right click > properties), and copy the new one into the directory over the old one (or rename the old one) if you are using Vista and have trouble).
  7. Restart Apache.

Now you can access that directory by browsing to http://transitcalculator.localhost/.


Make an Alias

  1. Starting ~line 200 of your http.conf file, copy everything between <Directory "C:/xampp/htdocs"> and </Directory> (~line 232) and paste it immediately below with C:/xampp/htdocs replaced with your desired directory (in this case C:/Projects) to give your server the correct permissions for the new directory.

  2. Find the <IfModule alias_module></IfModule> section (~line 300) and add

    Alias /transitCalculator "C:/Projects/transitCalculator/trunk"
    

    (or whatever is relevant to your desires) below the Alias comment block, inside the module tags.


Change your document root

  1. Edit ~line 176 in C:\xampp\apache\conf\httpd.conf; change DocumentRoot "C:/xampp/htdocs" to #DocumentRoot "C:/Projects" (or whatever you want).

  2. Edit ~line 203 to match your new location (in this case C:/Projects).


Notes:

  • You have to use forward slashes "/" instead of back slashes "\".
  • Don't include the trailing "/" at the end.
  • restart your server.

.NET obfuscation tools/strategy

Avoid Reactor. It is completely useless (and yes I paid for a license). Xenocode was the best one I encountered and bought a license for too. The support was very good but I didn't need it much as it just worked. I tested every obfuscator I could find and my conclusion is that xenocode was far and away the most robust and did the best job (also possibility to post process your .NET exe to a native exe which I didn't see anywhere else.).

There are two main differences between reactor and xenocode. The first one is that Xenocode actually works. The second is that the execution speed of your assemblies is no different. With reactor it was about 6 million times slower. I also got the impression that reactor was a one man operation.

Splitting a dataframe string column into multiple different columns

The way via unlist and matrix seems a bit convoluted, and requires you to hard-code the number of elements (this is actually a pretty big no-go. Of course you could circumvent hard-coding that number and determine it at run-time)

I would go a different route, and construct a data frame directly from the list that strsplit returns. For me, this is conceptually simpler. There are essentially two ways of doing this:

  1. as.data.frame – but since the list is exactly the wrong way round (we have a list of rows rather than a list of columns) we have to transpose the result. We also clear the rownames since they are ugly by default (but that’s strictly unnecessary!):

    `rownames<-`(t(as.data.frame(strsplit(text, '\\.'))), NULL)
    
  2. Alternatively, use rbind to construct a data frame from the list of rows. We use do.call to call rbind with all the rows as separate arguments:

    do.call(rbind, strsplit(text, '\\.'))
    

Both ways yield the same result:

     [,1] [,2] [,3]  [,4]
[1,] "F"  "US" "CLE" "V13"
[2,] "F"  "US" "CA6" "U13"
[3,] "F"  "US" "CA6" "U13"
[4,] "F"  "US" "CA6" "U13"
[5,] "F"  "US" "CA6" "U13"
[6,] "F"  "US" "CA6" "U13"
…

Clearly, the second way is much simpler than the first.

SQL Server Management Studio missing

Try restarting your computer if you just installed SQL Server and there's no choice in the SQL Server Installation Center to install SQL Server Management Studio.

This choice (see image below) only appeared for me after I installed SQL Server, then restarted my computer:

enter image description here

Why is my Button text forced to ALL CAPS on Lollipop?

By default, Button in android provides all caps keyword. If you want button text to be in lower case or mixed case you can disable textAllCaps flag using android:textAllCaps="false"

Difference between "while" loop and "do while" loop

While Loop:

while(test-condition)
{
      statements;
      increment/decrement;
}
  1. Lower Execution Time and Speed
  2. Entry Conditioned Loop
  3. No fixed number of iterations

Do While Loop:

do
{
      statements;
      increment/decrement;
}while(test-condition);
  1. Higher Execution Time and Speed
  2. Exit Conditioned Loop
  3. Minimum one number of iteration

Find out more on this topic here: Difference Between While and Do While Loop

This is valid for C programming, Java programming and other languages as well because the concepts remain the same, only the syntax changes.

Also, another small but a differentiating factor to note is that the do while loop consists of a semicolon at the end of the while condition.

Content Security Policy "data" not working for base64 Images in Chrome 28

Try this

data to load:

<svg xmlns='http://www.w3.org/2000/svg' viewBox='0 0 4 5'><path fill='#343a40' d='M2 0L0 2h4zm0 5L0 3h4z'/></svg>

get a utf8 to base64 convertor and convert the "svg" string to:

PHN2ZyB4bWxucz0naHR0cDovL3d3dy53My5vcmcvMjAwMC9zdmcnIHZpZXdCb3g9JzAgMCA0IDUn
PjxwYXRoIGZpbGw9JyMzNDNhNDAnIGQ9J00yIDBMMCAyaDR6bTAgNUwwIDNoNHonLz48L3N2Zz4=

and the CSP is

img-src data: image/svg+xml;base64,PHN2ZyB4bWxucz0naHR0cDovL3d3dy53My5vcmcvMjAwMC9zdmcnIHZpZXdCb3g9JzAgMCA0IDUn
PjxwYXRoIGZpbGw9JyMzNDNhNDAnIGQ9J00yIDBMMCAyaDR6bTAgNUwwIDNoNHonLz48L3N2Zz4=

Resetting MySQL Root Password with XAMPP on Localhost

Reset XAMPP MySQL root password through SQL update phpmyadmin to work with it:

-Start the Apache Server and MySQL instances from the XAMPP control panel. After the server started, open any web browser and go to http://localhost/phpmyadmin/. This will open the phpMyAdmin interface. Using this interface we can manager the MySQL server from the web browser.

-In the phpMyAdmin window, select SQL tab from the right panel. This will open the SQL tab where we can run the SQL queries.

-Now type the following query in the textarea and click Go

  • "UPDATE mysql.user SET Password=PASSWORD('password') WHERE User='root';"

  • hit go

  • "FLUSH PRIVILEGES;"

  • hit go

-Now you will see a message saying that the query has been executed successfully.

-If you refresh the page, you will be getting a error message. This is because the phpMyAdmin configuration file is not aware of our newly set root passoword. To do this we have to modify the phpMyAdmin config file.

-Open the file C:\xampp\phpMyAdmin\config.inc.php in your favorite text editor. Search for the string:

$cfg\['Servers'\]\[$i\]['password'] = ''; and change it to like this, 
$cfg\['Servers'\]\[$i\]['password'] = 'password'; Here the ‘password’ is what we set to the root user using the SQL query.
$cfg['Servers'][$i]['AllowNoPassword'] = false; // set to false for password required
$cfg['Servers'][$i]['auth_type'] = 'cookie'; // web cookie auth

-Now all set to go. Save the config.inc.php file and restart the XAMPP server.

Modified from Source: http://veerasundar.com/blog/2009/01/how-to-change-the-root-password-for-mysql-in-xampp/

Don't change link color when a link is clicked

Don't over complicate it. Just give the link a color using the tags. It will leave a constant color that won't change even if you click it. So in your case just set it to blue. If it is set to a particular color of blue just you want to copy, you can press "print scrn" on your keyboard, paste in paint, and using the color picker(shaped as a dropper) pick the color of the link and view the code in the color settings.

Scanf/Printf double variable C

For variable argument functions like printf and scanf, the arguments are promoted, for example, any smaller integer types are promoted to int, float is promoted to double.

scanf takes parameters of pointers, so the promotion rule takes no effect. It must use %f for float* and %lf for double*.

printf will never see a float argument, float is always promoted to double. The format specifier is %f. But C99 also says %lf is the same as %f in printf:

C99 §7.19.6.1 The fprintf function

l (ell) Specifies that a following d, i, o, u, x, or X conversion specifier applies to a long int or unsigned long int argument; that a following n conversion specifier applies to a pointer to a long int argument; that a following c conversion specifier applies to a wint_t argument; that a following s conversion specifier applies to a pointer to a wchar_t argument; or has no effect on a following a, A, e, E, f, F, g, or G conversion specifier.

ORDER BY the IN value list

I think this way is better :

SELECT * FROM "comments" WHERE ("comments"."id" IN (1,3,2,4))
    ORDER BY  id=1 DESC, id=3 DESC, id=2 DESC, id=4 DESC

How to find out client ID of component for ajax update/render? Cannot find component with expression "foo" referenced from "bar"

I know this already has a great answer by BalusC but here is a little trick I use to get the container to tell me the correct clientId.

  1. Remove the update on your component that is not working
  2. Put a temporary component with a bogus update within the component you were trying to update
  3. hit the page, the servlet exception error will tell you the correct client Id you need to reference.
  4. Remove bogus component and put correct clientId in the original update

Here is code example as my words may not describe it best.

<p:tabView id="tabs">
    <p:tab id="search" title="Search">                        
        <h:form id="insTable">
            <p:dataTable id="table" var="lndInstrument" value="#{instrumentBean.instruments}">
                <p:column>
                    <p:commandLink id="select"

Remove the failing update within this component

 oncomplete="dlg.show()">
                        <f:setPropertyActionListener value="#{lndInstrument}" 
                                        target="#{instrumentBean.selectedInstrument}" />
                        <h:outputText value="#{lndInstrument.name}" />
                    </p:commandLink>                                    
                </p:column>
            </p:dataTable>
            <p:dialog id="dlg" modal="true" widgetVar="dlg">
                <h:panelGrid id="display">

Add a component within the component of the id you are trying to update using an update that will fail

   <p:commandButton id="BogusButton" update="BogusUpdate"></p:commandButton>

                    <h:outputText value="Name:" />
                    <h:outputText value="#{instrumentBean.selectedInstrument.name}" />
                </h:panelGrid>
            </p:dialog>                            
        </h:form>
    </p:tab>
</p:tabView>

Hit this page and view the error. The error is: javax.servlet.ServletException: Cannot find component for expression "BogusUpdate" referenced from tabs:insTable: BogusButton

So the correct clientId to use would then be the bold plus the id of the target container (display in this case)

tabs:insTable:display

How to linebreak an svg text within javascript?

I have adapted a bit the solution by @steco, switching the dependency from d3 to jquery and adding the height of the text element as parameter

function wrap(text, width, height) {
  text.each(function(idx,elem) {
    var text = $(elem);
    text.attr("dy",height);
        var words = text.text().split(/\s+/).reverse(),
        word,
        line = [],
        lineNumber = 0,
        lineHeight = 1.1, // ems
        y = text.attr("y"),
        dy = parseFloat( text.attr("dy") ),
        tspan = text.text(null).append("tspan").attr("x", 0).attr("y", y).attr("dy", dy + "em");
    while (word = words.pop()) {
      line.push(word);
      tspan.text(line.join(" "));
      if (elem.getComputedTextLength() > width) {
        line.pop();
        tspan.text(line.join(" "));
        line = [word];
        tspan = text.append("tspan").attr("x", 0).attr("y", y).attr("dy", ++lineNumber * lineHeight + dy + "em").text(word);
      }
    }
  });
}

What is the difference between re.search and re.match?

search ⇒ find something anywhere in the string and return a match object.

match ⇒ find something at the beginning of the string and return a match object.

Get the element with the highest occurrence in an array

I came up with a shorter solution, but it's using lodash. Works with any data, not just strings. For objects can be used:

const mostFrequent = _.maxBy(Object.values(_.groupBy(inputArr, el => el.someUniqueProp)), arr => arr.length)[0];

This is for strings:

const mostFrequent = _.maxBy(Object.values(_.groupBy(inputArr, el => el)), arr => arr.length)[0];

Just grouping data under a certain criteria, then finding the largest group.

Option to ignore case with .contains method?

In Java 8 you can use the Stream interface:

return dvdList.stream().anyMatch(d -> d.getTitle().equalsIgnoreCase("SomeTitle"));

Remote debugging a Java application

This is how you should setup Eclipse Debugger for remote debugging:

Eclipse Settings:

1.Click the Run Button
2.Select the Debug Configurations
3.Select the “Remote Java Application”
4.New Configuration

  • Name : GatewayPortalProject
  • Project : GatewayPortal-portlet
  • Connection Type: Socket Attach
  • Connection Properties: i) localhost ii) 8787

For JBoss:

1.Change the /path/toJboss/jboss-eap-6.1/bin/standalone.conf in your vm as follows: Uncomment the following line by removing the #:

JAVA_OPTS="$JAVA_OPTS -agentlib:jdwp=transport=dt_socket,address=8787,server=y,suspend=n"

For Tomcat :

In catalina.bat file :

Step 1:

CATALINA_OPTS="-Xdebug -Xrunjdwp:transport=dt_socket,address=8000,server=y,suspend=n"

Step 2:

JPDA_OPTS="-agentlib:jdwp=transport=dt_socket,address=8000,server=y,suspend=n"

Step 3: Run Tomcat from command prompt like below:

catalina.sh jpda start

Then you need to set breakpoints in the Java classes you desire to debug.

How to convert current date to epoch timestamp?

That should do it

import time

date_time = '29.08.2011 11:05:02'
pattern = '%d.%m.%Y %H:%M:%S'
epoch = int(time.mktime(time.strptime(date_time, pattern)))
print epoch

How do I add a library (android-support-v7-appcompat) in IntelliJ IDEA

This is my solution:

  1. Copy&paste $ANDROID_SDK/extras/android/support/v7/appcompat to your project ROOT

  2. Open "Project Structure" on Intellij, click "Modules" on "Project Settings", then click "appcompat"->"android', make sure "Library Module" checkbox is checked.

  3. click "YOUR-PROJECT_NAME" under "appcompat", remove "android-support-v4" and "android-support-v7-compat"; ensure the checkbox before "appcompat" is checked. And, click "ok" to close "Project Structure" dialogue.

  4. back to the mainwindow, click "appcompat"->"libs" on the top-left project area. Right-click on "android-support-v4", select menuitem "Add as library", change "Add to Module" to "Your-project". Same with "android-support-v7-compat".

After doing above, intellij should be able to correctly find the android-support-XXXX modules.

Good Luck!

Why am I seeing net::ERR_CLEARTEXT_NOT_PERMITTED errors after upgrading to Cordova Android 8?

you should add

<base-config cleartextTrafficPermitted="true">
    <trust-anchors>
        <certificates src="system" />
    </trust-anchors>
</base-config>

to

resources/android/xml/network_security_config.xml

like this

<network-security-config>
<base-config cleartextTrafficPermitted="true">
    <trust-anchors>
        <certificates src="system" />
    </trust-anchors>
</base-config>

<domain-config cleartextTrafficPermitted="true">
    <domain includeSubdomains="true">localhost</domain>
</domain-config> </network-security-config>

Facebook login message: "URL Blocked: This redirect failed because the redirect URI is not whitelisted in the app’s Client OAuth Settings."

In my case, I just had to make sure I have my urls both with and without www for Application Domain and Redirect URLs:

enter image description here

In my case, I had to use: signin-facebook after my site url, for redirect url.

Open Jquery modal dialog on click event

$(function() {

$('#clickMe').click(function(event) {
    var mytext = $('#myText').val();

    $('<div id="dialog">'+mytext+'</div>').appendTo('body');        
    event.preventDefault();

        $("#dialog").dialog({                   
            width: 600,
            modal: true,
            close: function(event, ui) {
                $("#dialog").hide();
                }
            });
    }); //close click
});

Better to use .hide() instead of .remove(). With .remove() it returns undefined if you have pressed the link once, then close the modal and if you press the modal link again, it returns undefined with .remove.

With .hide() it doesnt and it works like a breeze. Ty for the snippet in the first hand!

"Cannot create an instance of OLE DB provider" error as Windows Authentication user

For error 7302 in particular, I discovered, in my registry, when looking for OraOLEDB.Oracle that the InprocServer32 location was wrong.

If that's the case, or you can't find that string in the registry, then you'll have to install or re-register the component.

I had to delete the key from the GUID level, and then find the ProgID (OraOLEDB.Oracle) key, and delete that too. (The ProgID links to the CLSID as a pair).

Then I re-registered OraOLEDB.Oracle by calling regsvr32.exe on ORAOLEDB*.dll.

Just re-registering alone didn't solve the problem, I had to delete the registry keys to make it point to the correct location. Alternatively, hack the InprocServer32 location.

Now I have error 7308, about single threaded apartments; rolling on!

Disable webkit's spin buttons on input type="number"?

You can also hide spinner with following trick :

input[type=number]::-webkit-inner-spin-button,
input[type=number]::-webkit-outer-spin-button {
  opacity:0;
  pointer-events:none;
}

multiprocessing.Pool: When to use apply, apply_async or map?

Regarding apply vs map:

pool.apply(f, args): f is only executed in ONE of the workers of the pool. So ONE of the processes in the pool will run f(args).

pool.map(f, iterable): This method chops the iterable into a number of chunks which it submits to the process pool as separate tasks. So you take advantage of all the processes in the pool.

How do I get the file name from a String containing the Absolute file path?

extract file name using java regex *.

public String extractFileName(String fullPathFile){
        try {
            Pattern regex = Pattern.compile("([^\\\\/:*?\"<>|\r\n]+$)");
            Matcher regexMatcher = regex.matcher(fullPathFile);
            if (regexMatcher.find()){
                return regexMatcher.group(1);
            }
        } catch (PatternSyntaxException ex) {
            LOG.info("extractFileName::pattern problem <"+fullPathFile+">",ex);
        }
        return fullPathFile;
    }

Git pull - Please move or remove them before you can merge

Apparently the files were added in remote repository, no matter what was the content of .gitignore file in the origin.

As the files exist in the remote repository, git has to pull them to your local work tree as well and therefore complains that the files already exist.

.gitignore is used only for scanning for the newly added files, it doesn't have anything to do with the files which were already added.

So the solution is to remove the files in your work tree and pull the latest version. Or the long-term solution is to remove the files from the repository if they were added by mistake.

A simple example to remove files from the remote branch is to

$git checkout <brachWithFiles>
$git rm -r *.extension
$git commit -m "fixin...."
$git push

Then you can try the $git merge again

What does `return` keyword mean inside `forEach` function?

The return exits the current function, but the iterations keeps on, so you get the "next" item that skips the if and alerts the 4...

If you need to stop the looping, you should just use a plain for loop like so:

$('button').click(function () {
   var arr = [1, 2, 3, 4, 5];
   for(var i = 0; i < arr.length; i++) {
     var n = arr[i]; 
     if (n == 3) {
         break;
      }
      alert(n);
   })
})

You can read more about js break & continue here: http://www.w3schools.com/js/js_break.asp

jump to line X in nano editor

According to section 2.2 of the manual, you can use the Escape key pressed twice in place of the CTRL key. This allowed me to use Nano's key combination for GO TO LINE when running Nano on a Jupyter/ JupyterHub and accessing through my browser. The normal key combination was getting 'swallowed' as the manual warns about can more often happen with the ALT key on some systems, and which can be replaced by one press of the ESCAPE key.
So for jump to line it was ESCAPE pressed twice, followed by shift key + dash key.

From milliseconds to hour, minutes, seconds and milliseconds

Maybe can be shorter an more elegant. But I did it.

public String getHumanTimeFormatFromMilliseconds(String millisecondS){
    String message = "";
    long milliseconds = Long.valueOf(millisecondS);
    if (milliseconds >= 1000){
        int seconds = (int) (milliseconds / 1000) % 60;
        int minutes = (int) ((milliseconds / (1000 * 60)) % 60);
        int hours = (int) ((milliseconds / (1000 * 60 * 60)) % 24);
        int days = (int) (milliseconds / (1000 * 60 * 60 * 24));
        if((days == 0) && (hours != 0)){
            message = String.format("%d hours %d minutes %d seconds ago", hours, minutes, seconds);
        }else if((hours == 0) && (minutes != 0)){
            message = String.format("%d minutes %d seconds ago", minutes, seconds);
        }else if((days == 0) && (hours == 0) && (minutes == 0)){
            message = String.format("%d seconds ago", seconds);
        }else{
            message = String.format("%d days %d hours %d minutes %d seconds ago", days, hours, minutes, seconds);
        }
    } else{
        message = "Less than a second ago.";
    }
    return message;
}

java.lang.UnsupportedClassVersionError

This was a fresh linux Mint xfce machine

I have been battling this for a about a week. I'm trying to learn Java on Netbeans IDE and so naturally I get the combo file straight from Oracle. Which is a package of the JDK and the Netbeans IDE together in a tar file located here.

located http://www.oracle.com/technetwork/java/javase/downloads/index.html file name JDK 8u25 with NetBeans 8.0.1

after installing them (or so I thought) I would make/compile a simple program like "hello world" and that would spit out a jar file that you would be able to run in a terminal. Keep in mind that the program ran in the Netbeans IDE.

I would end up with this error: java.lang.UnsupportedClassVersionError:

Even though I ran the file from oracle website I still had the old version of the Java runtime which was not compatible to run my jar file which was compiled with the new java runtime.

After messing with stuff that was mostly over my head from setting Paths to editing .bashrc with no remedy.

I came across a solution that was easy enough for even me. I have come across something that auto installs java and configures it on your system and it works with the latest 1.8.*

One of the steps is adding a PPA wasn't sure about this at first but seems ok as it has worked for me


sudo add-apt-repository ppa:webupd8team/java

sudo apt-get update

sudo apt-get install oracle-java8-installer


domenic@domenic-AO532h ~ $ java -version java version "1.8.0_25" Java(TM) SE Runtime Environment (build 1.8.0_25-b17) Java HotSpot(TM) Server VM (build 25.25-b02, mixed mode)

I think it also configures the browser java as well.

I hope this helps others.

How to log PostgreSQL queries?

You also need add these lines in PostgreSQL and restart the server:

log_directory = 'pg_log'                    
log_filename = 'postgresql-dateformat.log'
log_statement = 'all'
logging_collector = on

Text overwrite in visual studio 2010

press your keyboard Insert Key

How to remove td border with html?

<table border="1" cellspacing="0" cellpadding="0">
    <tr>
        <td>
            <table border="0">
                <tr>
                    <td>one</td>
                    <td>two</td>
                </tr>
                <tr>
                    <td>one</td>
                </tr>
            </table>
        </td>
    </tr>
</table>

CSS :selected pseudo class similar to :checked, but for <select> elements

the :checked pseudo-class initially applies to such elements that have the HTML4 selected and checked attributes

Source: w3.org


So, this CSS works, although styling the color is not possible in every browser:

option:checked { color: red; }

An example of this in action, hiding the currently selected item from the drop down list.

_x000D_
_x000D_
option:checked { display:none; }
_x000D_
<select>_x000D_
    <option>A</option>_x000D_
    <option>B</option>_x000D_
    <option>C</option>_x000D_
</select>
_x000D_
_x000D_
_x000D_


To style the currently selected option in the closed dropdown as well, you could try reversing the logic:

select { color: red; }
option:not(:checked) { color: black; } /* or whatever your default style is */

Comparing two columns, and returning a specific adjacent cell in Excel

In cell D2 and copied down:

=IF(COUNTIF($A$2:$A$5,C2)=0,"",VLOOKUP(C2,$A$2:$B$5,2,FALSE))

How can I output leading zeros in Ruby?

Can't you just use string formatting of the value before you concat the filename?

"%03d" % number

Control the size of points in an R scatterplot?

Try the cex argument:

?par

  • cex
    A numerical value giving the amount by which plotting text and symbols should be magnified relative to the default. Note that some graphics functions such as plot.default have an argument of this name which multiplies this graphical parameter, and some functions such as points accept a vector of values which are recycled. Other uses will take just the first value if a vector of length greater than one is supplied.

Free FTP Library

I like Alex FTPS Client which is written by a Microsoft MVP name Alex Pilotti. It's a C# library you can use in Console apps, Windows Forms, PowerShell, ASP.NET (in any .NET language). If you have a multithreaded app you will have to configure the library to run syncronously, but overall a good client that will most likely get you what you need.

Sorting Values of Set

Use the Integer wrapper class instead of String because it is doing the hard work for you by implementing Comparable<Integer>. Then java.util.Collections.sort(list); would do the trick.

Getting a list of values from a list of dicts

A very simple way to do it is:

list1=['']
j=0
for i in com_list:
    if j==0:
        list1[0]=(i['value'])
    else:
        list1.append(i['value'])
    j+=1

Output:

['apple', 'banana', 'cars']

In Python, how to display current time in readable format

First the quick and dirty way, and second the precise way (recognizing daylight's savings or not).

import time
time.ctime() # 'Mon Oct 18 13:35:29 2010'
time.strftime('%l:%M%p %Z on %b %d, %Y') # ' 1:36PM EDT on Oct 18, 2010'
time.strftime('%l:%M%p %z on %b %d, %Y') # ' 1:36PM EST on Oct 18, 2010'

Fatal error: Call to a member function fetch_assoc() on a non-object

Please check if you have already close the database connection or not. In my case i was getting the error because the connection was close in upper line.