SyntaxFix

Programs & Examples On #Pack

A function in several scripting languages for packing data into a binary structure. The opposite of the `unpack` function.

Remove large .pack file created by git

One option:

run git gc manually to condense a number of pack files into one or a few pack files. This operation is persistent (i.e. the large pack file will retain its compression behavior) so it may be beneficial to compress a repository periodically with git gc --aggressive

Another option is to save the code and .git somewhere and then delete the .git and start again using this existing code, creating a new git repository (git init).

exception in initializer error in java when using Netbeans

I found that I had bound jFormattedCheckBox1.foreground to jCheckBox1[${selected}].... this was the problem. Thank you for your help.

It seems that a color should not be able to be bound to a boolean. I guess bindings are an advanced feature?

I found the problem by deleting all of the controls, then running, then undoing and then deleting one at a time. When I found the offending control, I examined the properties.

Script parameters in Bash

The arguments that you provide to a bashscript will appear in the variables $1 and $2 and $3 where the number refers to the argument. $0 is the command itself.

The arguments are seperated by spaces, so if you would provide the -from and -to in the command, they will end up in these variables too, so for this:

./ocrscript.sh -from /home/kristoffer/test.png -to /home/kristoffer/test.txt

You'll get:

$0    # ocrscript.sh
$1    # -from
$2    # /home/kristoffer/test.png
$3    # -to
$4    # /home/kristoffer/test.txt

It might be easier to omit the -from and the -to, like:

ocrscript.sh /home/kristoffer/test.png /home/kristoffer/test.txt

Then you'll have:

$1    # /home/kristoffer/test.png
$2    # /home/kristoffer/test.txt

The downside is that you'll have to supply it in the right order. There are libraries that can make it easier to parse named arguments on the command line, but usually for simple shell scripts you should just use the easy way, if it's no problem.

Then you can do:

/usr/local/bin/abbyyocr9 -rl Swedish -if "$1" -of "$2" 2>&1

The double quotes around the $1 and the $2 are not always necessary but are adviced, because some strings won't work if you don't put them between double quotes.

How to check if all list items have the same value and return it, or return an “otherValue” if they don’t?

A slight variation on the above simplified approach.

var result = yyy.Distinct().Count() == yyy.Count();

How do I find out if first character of a string is a number?

Regular expressions are very strong but expensive tool. It is valid to use them for checking if the first character is a digit but it is not so elegant :) I prefer this way: 

public boolean isLeadingDigit(final String value){
    final char c = value.charAt(0);
    return (c >= '0' && c <= '9');
}

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

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

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

How to get the number of columns in a matrix?

Use the size() function.

>> size(A,2)

Ans =

   3

The second argument specifies the dimension of which number of elements are required which will be '2' if you want the number of columns.

Official documentation.

Add a tooltip to a div

 
<!doctype html>
<html lang="en">
<head>
  <meta charset="utf-8">
  <title>jQuery UI tooltip</title>
  <link rel="stylesheet" href="http://code.jquery.com/ui/1.11.0/themes/smoothness/jquery-ui.css">
  <script src="http://code.jquery.com/jquery-1.10.2.js"></script>
  <script src="http://code.jquery.com/ui/1.11.0/jquery-ui.js"></script>  
  <script>
  $(function() {
    $("#tooltip").tooltip();
  });
  </script>
</head>
<body>
<div id="tooltip" title="I am tooltip">mouse over me</div>
</body>
</html>

You can also customise tooltip style. Please refer this link: http://jqueryui.com/tooltip/#custom-style

Compute a confidence interval from sample data

 
import numpy as np
import scipy.stats


def mean_confidence_interval(data, confidence=0.95):
    a = 1.0 * np.array(data)
    n = len(a)
    m, se = np.mean(a), scipy.stats.sem(a)
    h = se * scipy.stats.t.ppf((1 + confidence) / 2., n-1)
    return m, m-h, m+h

you can calculate like this way.

align textbox and text/labels in html?

You have two boxes, left and right, for each label/input pair. Both boxes are in one row and have fixed width. Now, you just have to make label text float to the right with text-align: right;

Here's a simple example:

http://jsfiddle.net/qP46X/

How to specify preference of library path?

Add the path to where your new library is to LD_LIBRARY_PATH (it has slightly different name on Mac ...)

Your solution should work with using the -L/my/dir -lfoo options, at runtime use LD_LIBRARY_PATH to point to the location of your library.

Careful with using LD_LIBRARY_PATH - in short (from link):

..implications..:
Security: Remember that the directories specified in LD_LIBRARY_PATH get searched before(!) the standard locations? In that way, a nasty person could get your application to load a version of a shared library that contains malicious code! That’s one reason why setuid/setgid executables do neglect that variable!
Performance: The link loader has to search all the directories specified, until it finds the directory where the shared library resides – for ALL shared libraries the application is linked against! This means a lot of system calls to open(), that will fail with “ENOENT (No such file or directory)”! If the path contains many directories, the number of failed calls will increase linearly, and you can tell that from the start-up time of the application. If some (or all) of the directories are in an NFS environment, the start-up time of your applications can really get long – and it can slow down the whole system!
Inconsistency: This is the most common problem. LD_LIBRARY_PATH forces an application to load a shared library it wasn’t linked against, and that is quite likely not compatible with the original version. This can either be very obvious, i.e. the application crashes, or it can lead to wrong results, if the picked up library not quite does what the original version would have done. Especially the latter is sometimes hard to debug.

OR

Use the rpath option via gcc to linker - runtime library search path, will be used instead of looking in standard dir (gcc option):

-Wl,-rpath,$(DEFAULT_LIB_INSTALL_PATH)

This is good for a temporary solution. Linker first searches the LD_LIBRARY_PATH for libraries before looking into standard directories.

If you don't want to permanently update LD_LIBRARY_PATH you can do it on the fly on command line:

LD_LIBRARY_PATH=/some/custom/dir ./fooo

You can check what libraries linker knows about using (example):

/sbin/ldconfig -p | grep libpthread
        libpthread.so.0 (libc6, OS ABI: Linux 2.6.4) => /lib/libpthread.so.0

And you can check which library your application is using:

ldd foo
        linux-gate.so.1 =>  (0xffffe000)
        libpthread.so.0 => /lib/libpthread.so.0 (0xb7f9e000)
        libxml2.so.2 => /usr/lib/libxml2.so.2 (0xb7e6e000)
        librt.so.1 => /lib/librt.so.1 (0xb7e65000)
        libm.so.6 => /lib/libm.so.6 (0xb7d5b000)
        libc.so.6 => /lib/libc.so.6 (0xb7c2e000)
        /lib/ld-linux.so.2 (0xb7fc7000)
        libdl.so.2 => /lib/libdl.so.2 (0xb7c2a000)
        libz.so.1 => /lib/libz.so.1 (0xb7c18000)

How to prevent tensorflow from allocating the totality of a GPU memory?

For TensorFlow 2.0 and 2.1 (docs):

import tensorflow as tf
tf.config.gpu.set_per_process_memory_growth(True)

For TensorFlow 2.2+ (docs):

import tensorflow as tf
gpus = tf.config.experimental.list_physical_devices('GPU')
for gpu in gpus:
  tf.config.experimental.set_memory_growth(gpu, True)

The docs also list some more methods:

  • Set environment variable TF_FORCE_GPU_ALLOW_GROWTH to true.
  • Use tf.config.experimental.set_virtual_device_configuration to set a hard limit on a Virtual GPU device.

How to get Wikipedia content using Wikipedia's API?

You can use JQuery to do that. First create the url with appropriate parameters. Check this link to understand what the parameters mean. Then use $.ajax() method to retrieve the articles. Note that wikipedia does not allow cross origin request. That's why we are using dataType : jsonp in the request.

var wikiURL = "https://en.wikipedia.org/w/api.php";
wikiURL += '?' + $.param({
    'action' : 'opensearch',
    'search' : 'your_search_term',
    'prop'  : 'revisions',
    'rvprop' : 'content',
    'format' : 'json',
    'limit' : 10
});

 $.ajax( {
    url: wikiURL,
    dataType: 'jsonp',
    success: function(data) {
       console.log(data);
    }
} );

How to enter a formula into a cell using VBA?

I would do it like this:

Worksheets("EmployeeCosts").Range("B" & var1a).Formula = _
Replace("=SUM(H5:H{SOME_VAR})","{SOME_VAR}",var1a)

In case you have some more complex formula it will be handy

The SMTP server requires a secure connection or the client was not authenticated. The server response was: 5.5.1 Authentication Required?

First check for gmail's security related issues. You may have enabled double authentication in gmail. Also check your gmail inbox if you are getting any security alerts. In such cases check other answer of @mjb as below

Below is the very general thing that i always check first for such issues

client.UseDefaultCredentials = true;

set it to false.

Note @Joe King's answer - you must set client.UseDefaultCredentials before you set client.Credentials

How can I convert a stack trace to a string?

For me the cleanest and easiest way was:

import java.util.Arrays;
Arrays.toString(e.getStackTrace());

The type arguments cannot be inferred from the usage. Try specifying the type arguments explicitly

C# compiler have only lambda

arg => arg.MyProperty

for infer type of arg(TModel) an type of arg.MyProperty(TProperty). It's impossible.

Text size and different android screen sizes

@forcelain I think you need to check this Google IO Pdf for Design. In that pdf go to Page No:77 in which you will find how there suggesting for using dimens.xml for different devices of android for Example see Below structure :

res/values/dimens.xml

res/values-small/dimens.xml

res/values-normal/dimens.xml

res/values-large/dimens.xml

res/values-xlarge/dimens.xml

for Example you have used below dimens.xml in values.

<?xml version="1.0" encoding="utf-8"?>
<resources>
   <dimen name="text_size">18sp</dimen>
</resources>

In other values folder you need to change values for your text size .

Note: As indicated by @espinchi the small, normal, large and xlarge have been deprecated since Android 3.2 in favor of the following:

Declaring Tablet Layouts for Android 3.2

For the first generation of tablets running Android 3.0, the proper way to declare tablet layouts was to put them in a directory with the xlarge configuration qualifier (for example, res/layout-xlarge/). In order to accommodate other types of tablets and screen sizes—in particular, 7" tablets—Android 3.2 introduces a new way to specify resources for more discrete screen sizes. The new technique is based on the amount of space your layout needs (such as 600dp of width), rather than trying to make your layout fit the generalized size groups (such as large or xlarge).

The reason designing for 7" tablets is tricky when using the generalized size groups is that a 7" tablet is technically in the same group as a 5" handset (the large group). While these two devices are seemingly close to each other in size, the amount of space for an application's UI is significantly different, as is the style of user interaction. Thus, a 7" and 5" screen should not always use the same layout. To make it possible for you to provide different layouts for these two kinds of screens, Android now allows you to specify your layout resources based on the width and/or height that's actually available for your application's layout, specified in dp units.

For example, after you've designed the layout you want to use for tablet-style devices, you might determine that the layout stops working well when the screen is less than 600dp wide. This threshold thus becomes the minimum size that you require for your tablet layout. As such, you can now specify that these layout resources should be used only when there is at least 600dp of width available for your application's UI.

You should either pick a width and design to it as your minimum size, or test what is the smallest width your layout supports once it's complete.

Note: Remember that all the figures used with these new size APIs are density-independent pixel (dp) values and your layout dimensions should also always be defined using dp units, because what you care about is the amount of screen space available after the system accounts for screen density (as opposed to using raw pixel resolution). For more information about density-independent pixels, read Terms and concepts, earlier in this document. Using new size qualifiers

The different resource configurations that you can specify based on the space available for your layout are summarized in table 2. These new qualifiers offer you more control over the specific screen sizes your application supports, compared to the traditional screen size groups (small, normal, large, and xlarge).

Note: The sizes that you specify using these qualifiers are not the actual screen sizes. Rather, the sizes are for the width or height in dp units that are available to your activity's window. The Android system might use some of the screen for system UI (such as the system bar at the bottom of the screen or the status bar at the top), so some of the screen might not be available for your layout. Thus, the sizes you declare should be specifically about the sizes needed by your activity—the system accounts for any space used by system UI when declaring how much space it provides for your layout. Also beware that the Action Bar is considered a part of your application's window space, although your layout does not declare it, so it reduces the space available for your layout and you must account for it in your design.

Table 2. New configuration qualifiers for screen size (introduced in Android 3.2). Screen configuration Qualifier values Description smallestWidth swdp

Examples: sw600dp sw720dp

The fundamental size of a screen, as indicated by the shortest dimension of the available screen area. Specifically, the device's smallestWidth is the shortest of the screen's available height and width (you may also think of it as the "smallest possible width" for the screen). You can use this qualifier to ensure that, regardless of the screen's current orientation, your application's has at least dps of width available for its UI.

For example, if your layout requires that its smallest dimension of screen area be at least 600 dp at all times, then you can use this qualifier to create the layout resources, res/layout-sw600dp/. The system will use these resources only when the smallest dimension of available screen is at least 600dp, regardless of whether the 600dp side is the user-perceived height or width. The smallestWidth is a fixed screen size characteristic of the device; the device's smallestWidth does not change when the screen's orientation changes.

The smallestWidth of a device takes into account screen decorations and system UI. For example, if the device has some persistent UI elements on the screen that account for space along the axis of the smallestWidth, the system declares the smallestWidth to be smaller than the actual screen size, because those are screen pixels not available for your UI.

This is an alternative to the generalized screen size qualifiers (small, normal, large, xlarge) that allows you to define a discrete number for the effective size available for your UI. Using smallestWidth to determine the general screen size is useful because width is often the driving factor in designing a layout. A UI will often scroll vertically, but have fairly hard constraints on the minimum space it needs horizontally. The available width is also the key factor in determining whether to use a one-pane layout for handsets or multi-pane layout for tablets. Thus, you likely care most about what the smallest possible width will be on each device. Available screen width wdp

Examples: w720dp w1024dp

Specifies a minimum available width in dp units at which the resources should be used—defined by the value. The system's corresponding value for the width changes when the screen's orientation switches between landscape and portrait to reflect the current actual width that's available for your UI.

This is often useful to determine whether to use a multi-pane layout, because even on a tablet device, you often won't want the same multi-pane layout for portrait orientation as you do for landscape. Thus, you can use this to specify the minimum width required for the layout, instead of using both the screen size and orientation qualifiers together. Available screen height hdp

Examples: h720dp h1024dp etc.

Specifies a minimum screen height in dp units at which the resources should be used—defined by the value. The system's corresponding value for the height changes when the screen's orientation switches between landscape and portrait to reflect the current actual height that's available for your UI.

Using this to define the height required by your layout is useful in the same way as wdp is for defining the required width, instead of using both the screen size and orientation qualifiers. However, most apps won't need this qualifier, considering that UIs often scroll vertically and are thus more flexible with how much height is available, whereas the width is more rigid.

While using these qualifiers might seem more complicated than using screen size groups, it should actually be simpler once you determine the requirements for your UI. When you design your UI, the main thing you probably care about is the actual size at which your application switches between a handset-style UI and a tablet-style UI that uses multiple panes. The exact point of this switch will depend on your particular design—maybe you need a 720dp width for your tablet layout, maybe 600dp is enough, or 480dp, or some number between these. Using these qualifiers in table 2, you are in control of the precise size at which your layout changes.

For more discussion about these size configuration qualifiers, see the Providing Resources document. Configuration examples

To help you target some of your designs for different types of devices, here are some numbers for typical screen widths:

320dp: a typical phone screen (240x320 ldpi, 320x480 mdpi, 480x800 hdpi, etc).
480dp: a tweener tablet like the Streak (480x800 mdpi).
600dp: a 7” tablet (600x1024 mdpi).
720dp: a 10” tablet (720x1280 mdpi, 800x1280 mdpi, etc).

Using the size qualifiers from table 2, your application can switch between your different layout resources for handsets and tablets using any number you want for width and/or height. For example, if 600dp is the smallest available width supported by your tablet layout, you can provide these two sets of layouts:

res/layout/main_activity.xml # For handsets res/layout-sw600dp/main_activity.xml # For tablets

In this case, the smallest width of the available screen space must be 600dp in order for the tablet layout to be applied.

For other cases in which you want to further customize your UI to differentiate between sizes such as 7” and 10” tablets, you can define additional smallest width layouts:

res/layout/main_activity.xml # For handsets (smaller than 600dp available width) res/layout-sw600dp/main_activity.xml # For 7” tablets (600dp wide and bigger) res/layout-sw720dp/main_activity.xml

For 10” tablets (720dp wide and bigger)

Notice that the previous two sets of example resources use the "smallest width" qualifier, swdp, which specifies the smallest of the screen's two sides, regardless of the device's current orientation. Thus, using swdp is a simple way to specify the overall screen size available for your layout by ignoring the screen's orientation.

However, in some cases, what might be important for your layout is exactly how much width or height is currently available. For example, if you have a two-pane layout with two fragments side by side, you might want to use it whenever the screen provides at least 600dp of width, whether the device is in landscape or portrait orientation. In this case, your resources might look like this:

res/layout/main_activity.xml # For handsets (smaller than 600dp available width) res/layout-w600dp/main_activity.xml # Multi-pane (any screen with 600dp available width or more)

Notice that the second set is using the "available width" qualifier, wdp. This way, one device may actually use both layouts, depending on the orientation of the screen (if the available width is at least 600dp in one orientation and less than 600dp in the other orientation).

If the available height is a concern for you, then you can do the same using the hdp qualifier. Or, even combine the wdp and hdp qualifiers if you need to be really specific.

How do you add Boost libraries in CMakeLists.txt?

Adapting @LainIwakura's answer for modern CMake syntax with imported targets, this would be:

set(Boost_USE_STATIC_LIBS OFF) 
set(Boost_USE_MULTITHREADED ON)  
set(Boost_USE_STATIC_RUNTIME OFF) 
find_package(Boost 1.45.0 COMPONENTS filesystem regex) 

if(Boost_FOUND)
    add_executable(progname file1.cxx file2.cxx) 
    target_link_libraries(progname Boost::filesystem Boost::regex)
endif()

Note that it is not necessary anymore to specify the include directories manually, since it is already taken care of through the imported targets Boost::filesystem and Boost::regex.
regex and filesystem can be replaced by any boost libraries you need.

Import JSON file in React

 
var langs={
  ar_AR:require('./locale/ar_AR.json'),
  cs_CZ:require('./locale/cs_CZ.json'),
  de_DE:require('./locale/de_DE.json'),
  el_GR:require('./locale/el_GR.json'),
  en_GB:require('./locale/en_GB.json'),
  es_ES:require('./locale/es_ES.json'),
  fr_FR:require('./locale/fr_FR.json'),
  hu_HU:require('./locale/hu_HU.json')
}
module.exports=langs;

Require it in your module:

let langs=require('./languages');

regards

jQuery equivalent of JavaScript's addEventListener method

The closest thing would be the bind function:

http://api.jquery.com/bind/

$('#foo').bind('click', function() {
  alert('User clicked on "foo."');
});

Determining image file size + dimensions via Javascript?

Regarding the width and height:

var img = document.getElementById('imageId'); 

var width = img.clientWidth;
var height = img.clientHeight;

Regarding the filesize you can use performance

var size = performance.getEntriesByName(url)[0];
console.log(size.transferSize); // or decodedBodySize might differ if compression is used on server side

Call child component method from parent class - Angular

I had an exact situation where the Parent-component had a Select element in a form and on submit, I needed to call the relevant Child-Component's method according to the selected value from the select element.

Parent.HTML:

<form (ngSubmit)='selX' [formGroup]="xSelForm">
    <select formControlName="xSelector">
      ...
    </select>
<button type="submit">Submit</button>
</form>
<child [selectedX]="selectedX"></child>

Parent.TS:

selX(){
  this.selectedX = this.xSelForm.value['xSelector'];
}

Child.TS:

export class ChildComponent implements OnChanges {
  @Input() public selectedX;

  //ngOnChanges will execute if there is a change in the value of selectedX which has been passed to child as an @Input.

  ngOnChanges(changes: { [propKey: string]: SimpleChange }) {
    this.childFunction();
  }
  childFunction(){ }
}

Hope this helps.

Android Bitmap to Base64 String

Try this, first scale your image to required width and height, just pass your original bitmap, required width and required height to the following method and get scaled bitmap in return:

For example: Bitmap scaledBitmap = getScaledBitmap(originalBitmap, 250, 350);

private Bitmap getScaledBitmap(Bitmap b, int reqWidth, int reqHeight)
{
    int bWidth = b.getWidth();
    int bHeight = b.getHeight();

    int nWidth = bWidth;
    int nHeight = bHeight;

    if(nWidth > reqWidth)
    {
        int ratio = bWidth / reqWidth;
        if(ratio > 0)
        {
            nWidth = reqWidth;
            nHeight = bHeight / ratio;
        }
    }

    if(nHeight > reqHeight)
    {
        int ratio = bHeight / reqHeight;
        if(ratio > 0)
        {
            nHeight = reqHeight;
            nWidth = bWidth / ratio;
        }
    }

    return Bitmap.createScaledBitmap(b, nWidth, nHeight, true);
}

Now just pass your scaled bitmap to the following method and get base64 string in return:

For example: String base64String = getBase64String(scaledBitmap);

private String getBase64String(Bitmap bitmap)
{
    ByteArrayOutputStream baos = new ByteArrayOutputStream();

    bitmap.compress(Bitmap.CompressFormat.JPEG, 100, baos);

    byte[] imageBytes = baos.toByteArray();

    String base64String = Base64.encodeToString(imageBytes, Base64.NO_WRAP);

    return base64String;
}

To decode the base64 string back to bitmap image:

byte[] decodedByteArray = Base64.decode(base64String, Base64.NO_WRAP);
Bitmap decodedBitmap = BitmapFactory.decodeByteArray(decodedByteArray, 0, decodedString.length);

What is the easiest way to disable/enable buttons and links (jQuery + Bootstrap)

Great answer and contributions from all! I had to extend this function slightly to include disabling of select elements:

jQuery.fn.extend({
disable: function (state) {
    return this.each(function () {
        var $this = jQuery(this);
        if ($this.is('input, button'))
            this.disabled = state;
        else if ($this.is('select') && state)
            $this.attr('disabled', 'disabled');
        else if ($this.is('select') && !state)
            $this.removeAttr('disabled');
        else
            $this.toggleClass('disabled', state);
    });
}});

Seems to be working for me. Thanks all!

How can I increment a date by one day in Java?

In Java 8 simple way to do is:

Date.from(Instant.now().plusSeconds(SECONDS_PER_DAY))

How to copy Docker images from one host to another without using a repository

You can use a one-liner with DOCKER_HOST variable:

docker save app:1.0 | gzip | DOCKER_HOST=ssh://user@remotehost docker load

Datatable select with multiple conditions

Try this,
I think ,this is one of the simple solutions.

int rowIndex = table.Rows.IndexOf(table.Select("A = 'foo' AND B = 'bar' AND C = 'baz'")[0]);
string strD= Convert.ToString(table.Rows[rowIndex]["D"]);

Make sure,combination of values for column A, B and C is unique in the datatable.

Python basics printing 1 to 100

The answers here have pointed out that because after incrementing count it doesn't equal exactly 100, then it keeps going as the criteria isn't met (it's likely you want < to say less than 100).

I'll just add that you should really be looking at Python's builtin range function which generates a sequence of integers from a starting value, up to (but not including) another value, and an optional step - so you can adjust from adding 1 or 3 or 9 at a time...

0-100 (but not including 100, defaults starting from 0 and stepping by 1):

for number in range(100):
    print(number)

0-100 (but not including and makes sure number doesn't go above 100) in steps of 3:

for number in range(0, 100, 3):
    print(number)

Disable/Enable button in Excel/VBA

... I don't know if you're using an activex button or not, but when I insert an activex button into sheet1 in Excel called CommandButton1, the following code works fine:

Sub test()

   Sheets(1).CommandButton1.Enabled = False

End Sub

Hope this helps...

Bootstrap css hides portion of container below navbar navbar-fixed-top

I guess the problem you have is related to the dynamic height that the fixed navbar at the top has. For example, when a user logs in, you need to display some kind of "Hello [User Name]" and when the name is too wide, the navbar needs to use more height so this text doesn't overlap with the navbar menu. As the navbar has the style "position: fixed", the body stays underneath it and a taller part of it becomes hidden so you need to "dynamically" change the padding at the top every time the navbar height changes which would happen in the following case scenarios:

  1. The page is loaded / reloaded.
  2. The browser window is resized as this could hit a different responsive breakpoint.
  3. The navbar content is modified directly or indirectly as this could provoke a height change.

This dynamicity is not covered by regular CSS so I can only think of one way to solve this problem if the user has JavaScript enabled. Please try the following jQuery code snippet to resolve case scenarios 1 and 2; for case scenario 3 please remember to call the function onResize() after any change in the navbar content:

_x000D_
_x000D_ 
var onResize = function() {_x000D_
  // apply dynamic padding at the top of the body according to the fixed navbar height_x000D_
  $("body").css("padding-top", $(".navbar-fixed-top").height());_x000D_
};_x000D_
_x000D_
// attach the function to the window resize event_x000D_
$(window).resize(onResize);_x000D_
_x000D_
// call it also when the page is ready after load or reload_x000D_
$(function() {_x000D_
  onResize();_x000D_
});
_x000D_ 
<script src="https://ajax.googleapis.com/ajax/libs/jquery/1.10.2/jquery.min.js"></script>
_x000D_
_x000D_
_x000D_

How to remove decimal part from a number in C#

If you just need the integer part of the double then use explicit cast to int. 

int number = (int) a;

You may use Convert.ToInt32 Method (Double), but this will round the number to the nearest integer.

value, rounded to the nearest 32-bit signed integer. If value is halfway between two whole numbers, the even number is returned; that is, 4.5 is converted to 4, and 5.5 is converted to 6.

RestSharp simple complete example

Changing

RestResponse response = client.Execute(request);

to 

IRestResponse response = client.Execute(request);

worked for me.

Oracle SqlPlus - saving output in a file but don't show on screen

Right from the SQL*Plus manual
http://download.oracle.com/docs/cd/B19306_01/server.102/b14357/ch8.htm#sthref1597

SET TERMOUT

SET TERMOUT OFF suppresses the display so that you can spool output from a script without seeing it on the screen.

If both spooling to file and writing to terminal are not required, use SET TERMOUT OFF in >SQL scripts to disable terminal output.

SET TERMOUT is not supported in iSQL*Plus

random.seed(): What does it do?

random.seed(a, version) in python is used to initialize the pseudo-random number generator (PRNG).

PRNG is algorithm that generates sequence of numbers approximating the properties of random numbers. These random numbers can be reproduced using the seed value. So, if you provide seed value, PRNG starts from an arbitrary starting state using a seed.

Argument a is the seed value. If the a value is None, then by default, current system time is used.

and version is An integer specifying how to convert the a parameter into a integer. Default value is 2.

import random
random.seed(9001)
random.randint(1, 10) #this gives output of 1
# 1

If you want the same random number to be reproduced then provide the same seed again

random.seed(9001)
random.randint(1, 10) # this will give the same output of 1
# 1

If you don't provide the seed, then it generate different number and not 1 as before

random.randint(1, 10) # this gives 7 without providing seed
# 7

If you provide different seed than before, then it will give you a different random number

random.seed(9002)
random.randint(1, 10) # this gives you 5 not 1
# 5

So, in summary, if you want the same random number to be reproduced, provide the seed. Specifically, the same seed.

How to deal with page breaks when printing a large HTML table

 
<!DOCTYPE HTML>
<html>
<head>
<meta http-equiv="Content-Type" content="text/html; charset=UTF-8">
<title>Test</title>
<style type="text/css">
    table { page-break-inside:auto }
    tr    { page-break-inside:avoid; page-break-after:auto }
    thead { display:table-header-group }
    tfoot { display:table-footer-group }
</style>
</head>
<body>
    <table>
        <thead>
            <tr><th>heading</th></tr>
        </thead>
        <tfoot>
            <tr><td>notes</td></tr>
        </tfoot>
        <tbody>
        <tr>
            <td>x</td>
        </tr>
        <tr>
            <td>x</td>
        </tr>
        <!-- 500 more rows -->
        <tr>
            <td>x</td>
        </tr>
    </tbody>
    </table>
</body>
</html>

git clone error: RPC failed; curl 56 OpenSSL SSL_read: SSL_ERROR_SYSCALL, errno 10054

(based on anser from Hakan Fistik)

You can also set the postBuffer globally, which might be necessary, if you haven't checkout out the repository yet!

git config http.postBuffer 524288000

Not equal string

It should be this:

if (myString!="-1")
{
//Do things
}

Your equals and exclamation are the wrong way round.

non static method cannot be referenced from a static context

You are calling nextInt statically by using Random.nextInt.

Instead, create a variable, Random r = new Random(); and then call r.nextInt(10).

It would be definitely worth while to check out:

Update:

You really should replace this line,

Random Random = new Random();

with something like this,

Random r = new Random();

If you use variable names as class names you'll run into a boat load of problems. Also as a Java convention, use lowercase names for variables. That might help avoid some confusion.

How to use PowerShell select-string to find more than one pattern in a file?

If you want to match the two words in either order, use:

gci C:\Logs| select-string -pattern '(VendorEnquiry.*Failed)|(Failed.*VendorEnquiry)'

If Failed always comes after VendorEnquiry on the line, just use:

gci C:\Logs| select-string -pattern '(VendorEnquiry.*Failed)'

How to add image that is on my computer to a site in css or html?

The image needs to be in the same folder that your html page is in, then create a href to that folder with the picture name at the end. Example:

<img src="C:\users\home\pictures\picture.png"/>

How to sort a collection by date in MongoDB?

if your date format is like this : 14/02/1989 ----> you may find some problems

you need to use ISOdate like this :

var start_date = new Date(2012, 07, x, x, x);

-----> the result ------>ISODate("2012-07-14T08:14:00.201Z")

now just use the query like this :

 collection.find( { query : query ,$orderby :{start_date : -1}} ,function (err, cursor) {...}

that's it :)

ERROR 2002 (HY000): Can't connect to local MySQL server through socket '/var/run/mysqld/mysql.sock' (2)

You must do:

ls -lart /var/run/mysqld/
mkdir /var/run/mysqld
touch /var/run/mysqld/myssqld.sock
ls -lart /var/run/mysqld/
chown -R mysql /var/run/mysqld/
ls -lart /var/run/mysqld/
/etc/init.d/mysql restart

Then access like so:

mysql -u root -p
mysql> show databases;

ORA-01653: unable to extend table by in tablespace ORA-06512

You could also turn on autoextend for the whole database using this command:

ALTER DATABASE DATAFILE 'C:\ORACLEXE\APP\ORACLE\ORADATA\XE\SYSTEM.DBF'
AUTOEXTEND ON NEXT 1M MAXSIZE 1024M;

Just change the filepath to point to your system.dbf file.

Credit Here

View tabular file such as CSV from command line

Have a look at csvkit. It provides a set of tools that adhere to the UNIX philosophy (meaning they are small, simple, single-purposed and can be combined).

Here is an example that extracts the ten most populated cities in Germany from the free Maxmind World Cities database and displays the result in a console-readable format:

$ csvgrep -e iso-8859-1 -c 1 -m "de" worldcitiespop | csvgrep -c 5 -r "\d+" 
  | csvsort -r -c 5 -l | csvcut -c 1,2,4,6 | head -n 11 | csvlook
-----------------------------------------------------
|  line_number | Country | AccentCity | Population  |
-----------------------------------------------------
|  1           | de      | Berlin     | 3398362     |
|  2           | de      | Hamburg    | 1733846     |
|  3           | de      | Munich     | 1246133     |
|  4           | de      | Cologne    | 968823      |
|  5           | de      | Frankfurt  | 648034      |
|  6           | de      | Dortmund   | 594255      |
|  7           | de      | Stuttgart  | 591688      |
|  8           | de      | Düsseldorf | 577139      |
|  9           | de      | Essen      | 576914      |
|  10          | de      | Bremen     | 546429      |
-----------------------------------------------------

Csvkit is platform independent because it is written in Python.

Get the week start date and week end date from week number

I just encounter a similar case with this one, but the solution here seems not helping me. So I try to figure it out by myself. I work out the week start date only, week end date should be of similar logic.

Select 
      Sum(NumberOfBrides) As [Wedding Count], 
      DATEPART( wk, WeddingDate) as [Week Number],
      DATEPART( year, WeddingDate) as [Year],
      DATEADD(DAY, 1 - DATEPART(WEEKDAY, dateadd(wk, DATEPART( wk, WeddingDate)-1,  DATEADD(yy,DATEPART( year, WeddingDate)-1900,0))), dateadd(wk, DATEPART( wk, WeddingDate)-1, DATEADD(yy,DATEPART( year, WeddingDate)-1900,0))) as [Week Start]

FROM  MemberWeddingDates
Group By DATEPART( year, WeddingDate), DATEPART( wk, WeddingDate)
Order By Sum(NumberOfBrides) Desc

Maven error "Failure to transfer..."

Please Make sure that settings.XML file in the folder .m2 is valid first Then after clean the repository using below command in cmd

cd %userprofile%\.m2\repository
for /r %i in (*.lastUpdated) do del %i

Angular and debounce

We can create a [debounce] directive which overwrites ngModel's default viewToModelUpdate function with an empty one.

Directive Code

@Directive({ selector: '[debounce]' })
export class MyDebounce implements OnInit {
    @Input() delay: number = 300;

    constructor(private elementRef: ElementRef, private model: NgModel) {
    }

    ngOnInit(): void {
        const eventStream = Observable.fromEvent(this.elementRef.nativeElement, 'keyup')
            .map(() => {
                return this.model.value;
            })
            .debounceTime(this.delay);

        this.model.viewToModelUpdate = () => {};

        eventStream.subscribe(input => {
            this.model.viewModel = input;
            this.model.update.emit(input);
        });
    }
}

How to use it

<div class="ui input">
  <input debounce [delay]=500 [(ngModel)]="myData" type="text">
</div>

String.strip() in Python

If you can comment out code and your program still works, then yes, that code was optional.

.strip() with no arguments (or None as the first argument) removes all whitespace at the start and end, including spaces, tabs, newlines and carriage returns. Leaving it in doesn't do any harm, and allows your program to deal with unexpected extra whitespace inserted into the file.

For example, by using .strip(), the following two lines in a file would lead to the same end result:

 foo\tbar \n
foo\tbar\n

I'd say leave it in.

Can I have multiple primary keys in a single table?

A primary key is the key that uniquely identifies a record and is used in all indexes. This is why you can't have more than one. It is also generally the key that is used in joining to child tables but this is not a requirement. The real purpose of a PK is to make sure that something allows you to uniquely identify a record so that data changes affect the correct record and so that indexes can be created.

However, you can put multiple fields in one primary key (a composite PK). This will make your joins slower (espcially if they are larger string type fields) and your indexes larger but it may remove the need to do joins in some of the child tables, so as far as performance and design, take it on a case by case basis. When you do this, each field itself is not unique, but the combination of them is. If one or more of the fields in a composite key should also be unique, then you need a unique index on it. It is likely though that if one field is unique, this is a better candidate for the PK.

Now at times, you have more than one candidate for the PK. In this case you choose one as the PK or use a surrogate key (I personally prefer surrogate keys for this instance). And (this is critical!) you add unique indexes to each of the candidate keys that were not chosen as the PK. If the data needs to be unique, it needs a unique index whether it is the PK or not. This is a data integrity issue. (Note this is also true anytime you use a surrogate key; people get into trouble with surrogate keys because they forget to create unique indexes on the candidate keys.)

There are occasionally times when you want more than one surrogate key (which are usually the PK if you have them). In this case what you want isn't more PK's, it is more fields with autogenerated keys. Most DBs don't allow this, but there are ways of getting around it. First consider if the second field could be calculated based on the first autogenerated key (Field1 * -1 for instance) or perhaps the need for a second autogenerated key really means you should create a related table. Related tables can be in a one-to-one relationship. You would enforce that by adding the PK from the parent table to the child table and then adding the new autogenerated field to the table and then whatever fields are appropriate for this table. Then choose one of the two keys as the PK and put a unique index on the other (the autogenerated field does not have to be a PK). And make sure to add the FK to the field that is in the parent table. In general if you have no additional fields for the child table, you need to examine why you think you need two autogenerated fields.

What does the "@" symbol do in Powershell?

You can also wrap the output of a cmdlet (or pipeline) in @() to ensure that what you get back is an array rather than a single item.

For instance, dir usually returns a list, but depending on the options, it might return a single object. If you are planning on iterating through the results with a foreach-object, you need to make sure you get a list back. Here's a contrived example:

$results = @( dir c:\autoexec.bat)

One more thing... an empty array (like to initialize a variable) is denoted @().

Making a cURL call in C#

Or in restSharp:

var client = new RestClient("https://example.com/?urlparam=true");
var request = new RestRequest(Method.POST);
request.AddHeader("content-type", "application/x-www-form-urlencoded");
request.AddHeader("cache-control", "no-cache");
request.AddHeader("header1", "headerval");
request.AddParameter("application/x-www-form-urlencoded", "bodykey=bodyval", ParameterType.RequestBody);
IRestResponse response = client.Execute(request);

Xcode 12, building for iOS Simulator, but linking in object file built for iOS, for architecture arm64

For Pod Developers In your Podspec add:

s.pod_target_xcconfig = { 'EXCLUDED_ARCHS[sdk=iphonesimulator*]' => 'arm64' }
s.user_target_xcconfig = { 'EXCLUDED_ARCHS[sdk=iphonesimulator*]' => 'arm64' }

Then in your sample project Sample project files settings

See it working in this project

What causes this error? "Runtime error 380: Invalid property value"

What causes runtime error 380? Attempting to set a property of an object or control to a value that is not allowed. Look through the code that runs when your search form loads (Form_Load etc.) for any code that sets a property to something that depends on runtime values.

My other advice is to add some error handling and some logging to track down the exact line that is causing the error.

  • Logging Sprinkle statements through the code that say "Got to X", "Got to Y", etc. Use these to find the exact location of the error. You can write to a text file or the event log or use OutputDebugString.
  • Error handling Here's how to get a stack trace for the error. Add an error handler to every routine that might be involved, like this code below. The essential free tool MZTools can do this automatically. You could also use Erl to report line numbers and find the exact line - MZTools can automatically put in line numbers for you.

_

 On Error Goto Handler
   <routine contents>   
 Handler: 
   Err.Raise Err.Number, "(function_name)->" & Err.source, Err.Description

Powershell: Get FQDN Hostname

Here's the method that I've always used:

$fqdn= $(ping localhost -n 1)[1].split(" ")[1]

LINQ to SQL: Multiple joins ON multiple Columns. Is this possible?

U can also use :

var query =
    from t1 in myTABLE1List 
    join t2 in myTABLE1List
      on new { ColA=t1.ColumnA, ColB=t1.ColumnB } equals new { ColA=t2.ColumnA, ColB=t2.ColumnB }
    join t3 in myTABLE1List
      on new {ColC=t2.ColumnA, ColD=t2.ColumnB } equals new { ColC=t3.ColumnA, ColD=t3.ColumnB }

Tomcat in Intellij Idea Community Edition

The maven plugin and embedded Tomcat are usable work-arounds (I like second better because you can debug) but actual web server integration is a feature only available in intelij paid editions.

After installing with pip, "jupyter: command not found"

Once you run pip install jupyter. Make sure you restart the terminal so it would update environment and home variable. This worked for me

How to get an ASP.NET MVC Ajax response to redirect to new page instead of inserting view into UpdateTargetId?

The behavior you're trying to produce is not really best done using AJAX. AJAX would be best used if you wanted to only update a portion of the page, not completely redirect to some other page. That defeats the whole purpose of AJAX really.

I would suggest to just not use AJAX with the behavior you're describing.

Alternatively, you could try using jquery Ajax, which would submit the request and then you specify a callback when the request completes. In the callback you could determine if it failed or succeeded, and redirect to another page on success. I've found jquery Ajax to be much easier to use, especially since I'm already using the library for other things anyway.

You can find documentation about jquery ajax here, but the syntax is as follows:

jQuery.ajax( options )  

jQuery.get( url, data, callback, type)

jQuery.getJSON( url, data, callback )

jQuery.getScript( url, callback )

jQuery.post( url, data, callback, type)

RSA Public Key format

Reference Decoder of CRL,CRT,CSR,NEW CSR,PRIVATE KEY, PUBLIC KEY,RSA,RSA Public Key Parser

RSA Public Key 

-----BEGIN RSA PUBLIC KEY-----
-----END RSA PUBLIC KEY-----

Encrypted Private Key 

-----BEGIN RSA PRIVATE KEY-----
Proc-Type: 4,ENCRYPTED
-----END RSA PRIVATE KEY-----

CRL 

-----BEGIN X509 CRL-----
-----END X509 CRL-----

CRT 

-----BEGIN CERTIFICATE-----
-----END CERTIFICATE-----

CSR

-----BEGIN CERTIFICATE REQUEST-----
-----END CERTIFICATE REQUEST-----

NEW CSR

-----BEGIN NEW CERTIFICATE REQUEST-----
-----END NEW CERTIFICATE REQUEST-----

PEM

-----BEGIN RSA PRIVATE KEY-----
-----END RSA PRIVATE KEY-----

PKCS7

-----BEGIN PKCS7-----
-----END PKCS7-----

PRIVATE KEY

-----BEGIN PRIVATE KEY-----
-----END PRIVATE KEY-----

DSA KEY

-----BEGIN DSA PRIVATE KEY-----
-----END DSA PRIVATE KEY-----

Elliptic Curve

-----BEGIN EC PRIVATE KEY-----
-----END EC PRIVATE KEY-----

PGP Private Key

-----BEGIN PGP PRIVATE KEY BLOCK-----
-----END PGP PRIVATE KEY BLOCK-----

PGP Public Key

-----BEGIN PGP PUBLIC KEY BLOCK-----
-----END PGP PUBLIC KEY BLOCK-----

Increasing the maximum number of TCP/IP connections in Linux

To improve upon the answer given by derobert,

You can determine what your OS connection limit is by catting nf_conntrack_max.

For example: cat /proc/sys/net/netfilter/nf_conntrack_max

You can use the following script to count the number of tcp connections to a given range of tcp ports. By default 1-65535.

This will confirm whether or not you are maxing out your OS connection limit.

Here's the script.

#!/bin/bash
OS=$(uname)

case "$OS" in
    'SunOS')
            AWK=/usr/bin/nawk
            ;;
    'Linux')
            AWK=/bin/awk
            ;;
    'AIX')
            AWK=/usr/bin/awk
            ;;
esac

netstat -an | $AWK -v start=1 -v end=65535 ' $NF ~ /TIME_WAIT|ESTABLISHED/ && $4 !~ /127\.0\.0\.1/ {
    if ($1 ~ /\./)
            {sip=$1}
    else {sip=$4}

    if ( sip ~ /:/ )
            {d=2}
    else {d=5}

    split( sip, a, /:|\./ )

    if ( a[d] >= start && a[d] <= end ) {
            ++connections;
            }
    }
    END {print connections}'

How can a Java program get its own process ID?

Since Java 9 there is a method Process.getPid() which returns the native ID of a process:

public abstract class Process {

    ...

    public long getPid();
}

To get the process ID of the current Java process one can use the ProcessHandle interface:

System.out.println(ProcessHandle.current().pid());

How do you handle a "cannot instantiate abstract class" error in C++?

Why can't we create Object of Abstract Class ? When we create a pure virtual function in Abstract class, we reserve a slot for a function in the VTABLE(studied in last topic), but doesn't put any address in that slot. Hence the VTABLE will be incomplete. As the VTABLE for Abstract class is incomplete, hence the compiler will not let the creation of object for such class and will display an errror message whenever you try to do so.

Pure Virtual definitions

Pure Virtual functions can be given a small definition in the Abstract class, which you want all the derived classes to have. Still you cannot create object of Abstract class. Also, the Pure Virtual function must be defined outside the class definition. If you will define it inside the class definition, complier will give an error. Inline pure virtual definition is Illegal.

How to display a JSON representation and not [Object Object] on the screen

If you want to see what you you have inside an object in your web app, then use the json pipe in a component HTML template, for example:

<li *ngFor="let obj of myArray">{{obj | json}}</li>

Tested and valid using Angular 4.3.2.

How to create a dynamic array of integers

 
int main()
{
  int size;

  std::cin >> size;

  int *array = new int[size];

  delete [] array;

  return 0;
}

Don't forget to delete every array you allocate with new.

Is the MIME type 'image/jpg' the same as 'image/jpeg'?

tl;dr the "standards" are a hodge-podge mess; it depends who you ask!

Overall, there appears to be no MIME type image/jpg. Yet, in practice, nearly all software handles image files named "*.jpg" just fine.
This particular topic is confusing because the varying association of file name extension associated to a MIME type depends which organization created the table of file name extensions to MIME types. In other words, file name extension .jpg could be many different things.

For example, here are three "complete lists" and one RFC that with varying JPEG Image format file name extensions and the associated MIME types.

These "complete lists" and RFC do not have MIME type image/jpg! But for MIME type image/jpeg some lists do have varying file name extensions (.jpeg, .jpg, …). Other lists do not mention image/jpeg.

Also, there are different types of JPEG Image formats (e.g. Progressive JPEG Image format, JPEG 2000, etcetera) and "JPEG Extensions" that may or may not overlap in file name extension and declared MIME type.

Another confusing thing is RFC 3745 does not appear to match IANA Media Types yet the same RFC is supposed to inform the IANA Media Types document. For example, in RFC 3745 .jpf is preferred file extension for image/jpx but in IANA Media Types the name jpf is not present (and that IANA document references RFC 3745!).

Another confusing thing is IANA Media Types lists "names" but does not list "file name extensions". This is on purpose, but confuses the endeavor of mapping file name extensions to MIME types.

Another confusing thing: is it "mime", or "MIME", or "MIME type", or "mime type", or "mime/type", or "media type"?


The most official seeming document by IANA is surprisingly inadequate. No MIME type is registered for file extension .jpg yet there exists the odd vnd.sealedmedia.softseal.jpg. File extension.JPEG is only known as a video type while file extension .jpeg is an image type (when did lowercase and uppercase letters start mattering!?). At the same time, jpeg2000 is type video yet RFC 3745 considers JPEG 2000 an image type! The IANA list seems to cater to company-specific jpeg formats (e.g. vnd.sealedmedia.softseal.jpg).


In summary...

Because of the prior confusions, it is difficult to find an industry-accepted canonical document that maps file name extensions to MIME types, particularly for the JPEG Image File Format.


Related question "List of ALL MimeTypes on the Planet, mapped to File Extensions?".

Can't load AMD 64-bit .dll on a IA 32-bit platform

Uninstall(delete) this: jre, jdk, eclipse. Download 32 bit(x86) version of this programs:jre, jdk, eclipse. And install it.

Class name does not name a type in C++

 
error 'Class' does not name a type

Just in case someone does the same idiotic thing I did ... I was creating a small test program from scratch and I typed Class instead of class (with a small C). I didn't take any notice of the quotes in the error message and spent a little too long not understanding my problem.

My search for a solution brought me here so I guess the same could happen to someone else.

How to view changes made to files on a certain revision in Subversion

Call this in the project:

svn diff -r REVNO:HEAD --summarize

REVNO is the start revision number and HEAD is the end revision number. If HEAD is equal to the last revision number, it can skip it.

The command returns a list with all files that are changed/added/deleted in this revision period.

The command can be called with the URL revision parameter to check changes like this:

svn diff -r REVNO:HEAD --summarize SVN_URL

PostgreSQL: days/months/years between two dates

This question is full of misunderstandings. First lets understand the question fully. The asker wants to get the same result as for when running the MS SQL Server function DATEDIFF ( datepart , startdate , enddate ) where datepart takes dd, mm, or yy.

This function is defined by:

This function returns the count (as a signed integer value) of the specified datepart boundaries crossed between the specified startdate and enddate.

That means how many day boundaries, month boundaries, or year boundaries, are crossed. Not how many days, months, or years it is between them. That's why datediff(yy, '2010-04-01', '2012-03-05') is 2, and not 1. There is less than 2 years between those dates, meaning only 1 whole year has passed, but 2 year boundaries have crossed, from 2010 to 2011, and from 2011 to 2012.

The following are my best attempt at replicating the logic correctly.

-- datediff(dd`, '2010-04-01', '2012-03-05') = 704 // 704 changes of day in this interval
select ('2012-03-05'::date - '2010-04-01'::date );
-- 704 changes of day

-- datediff(mm, '2010-04-01', '2012-03-05') = 23  // 23 changes of month
select (date_part('year', '2012-03-05'::date) - date_part('year', '2010-04-01'::date)) * 12 + date_part('month', '2012-03-05'::date) - date_part('month', '2010-04-01'::date)
-- 23 changes of month

-- datediff(yy, '2010-04-01', '2012-03-05') = 2   // 2 changes of year
select date_part('year', '2012-03-05'::date) - date_part('year', '2010-04-01'::date);
-- 2 changes of year

How to get DataGridView cell value in messagebox?

You can use the DataGridViewCell.Value Property to retrieve the value stored in a particular cell.

So to retrieve the value of the 'first' selected Cell and display in a MessageBox, you can:

MessageBox.Show(dataGridView1.SelectedCells[0].Value.ToString());

The above probably isn't exactly what you need to do. If you provide more details we can provide better help.

What is the Linux equivalent to DOS pause?

read without any parameters will only continue if you press enter. The DOS pause command will continue if you press any key. Use read –n1 if you want this behaviour.

VBA Runtime Error 1004 "Application-defined or Object-defined error" when Selecting Range

You may receive a "Run-time error 1004" error message when you programmatically set a large array string to a range in Excel 2003

In Office Excel 2003, when you programmatically set a range value with an array containing a large string, you may receive an error message similar to the following:

Run-time error '1004'. Application-defined or operation-defined error.

This issue may occur if one or more of the cells in an array (range of cells) contain a character string that is set to contain more than 911 characters.

To work around this issue, edit the script so that no cells in the array contain a character string that holds more than 911 characters.

For example, the following line of code from the example code block below defines a character string that contains 912 characters:

Sub XLTest()
Dim aValues(4)

  aValues(0) = "Test1"
  aValues(1) = "Test2"
  aValues(2) = "Test3"

  MsgBox "First the Good range set."
  aValues(3) = String(911, 65)

  Range("A1:D1").Value = aValues

  MsgBox "Now the bad range set."
  aValues(3) = String(912, 66)
  Range("A2:D2").Value = aValues

End Sub

Other versions of Excel or free alternatives like Calc should work as well.

Insert data into hive table

If table is without partition then code will be,

Insert into table table_name select col_a,col_b,col_c from another_table(source table)

--here any condition can be applied such as limit, group by, order by etc...

If table is with partitions then code will be,

set hive.exec.dynamic.partition=true;
set hive.exec.dynamic.partition.mode=nonstrict;

insert into table table_name partition(partition_col1, paritition_col2) select col_a,col_b,col_c,partition_col1,partition_col2 from another_table(source table)

--here any condition can be applied such as limit, group by, order by etc...

What is the difference between Views and Materialized Views in Oracle?

A view uses a query to pull data from the underlying tables.

A materialized view is a table on disk that contains the result set of a query.

Materialized views are primarily used to increase application performance when it isn't feasible or desirable to use a standard view with indexes applied to it. Materialized views can be updated on a regular basis either through triggers or by using the ON COMMIT REFRESH option. This does require a few extra permissions, but it's nothing complex. ON COMMIT REFRESH has been in place since at least Oracle 10.

Task vs Thread differences

Source

Thread

Thread represents an actual OS-level thread, with its own stack and kernel resources. (technically, a CLR implementation could use fibers instead, but no existing CLR does this) Thread allows the highest degree of control; you can Abort() or Suspend() or Resume() a thread (though this is a very bad idea), you can observe its state, and you can set thread-level properties like the stack size, apartment state, or culture.

The problem with Thread is that OS threads are costly. Each thread you have consumes a non-trivial amount of memory for its stack, and adds additional CPU overhead as the processor context-switch between threads. Instead, it is better to have a small pool of threads execute your code as work becomes available.

There are times when there is no alternative Thread. If you need to specify the name (for debugging purposes) or the apartment state (to show a UI), you must create your own Thread (note that having multiple UI threads is generally a bad idea). Also, if you want to maintain an object that is owned by a single thread and can only be used by that thread, it is much easier to explicitly create a Thread instance for it so you can easily check whether code trying to use it is running on the correct thread.

ThreadPool

ThreadPool is a wrapper around a pool of threads maintained by the CLR. ThreadPool gives you no control at all; you can submit work to execute at some point, and you can control the size of the pool, but you can't set anything else. You can't even tell when the pool will start running the work you submit to it.

Using ThreadPool avoids the overhead of creating too many threads. However, if you submit too many long-running tasks to the threadpool, it can get full, and later work that you submit can end up waiting for the earlier long-running items to finish. In addition, the ThreadPool offers no way to find out when a work item has been completed (unlike Thread.Join()), nor a way to get the result. Therefore, ThreadPool is best used for short operations where the caller does not need the result.

Task

Finally, the Task class from the Task Parallel Library offers the best of both worlds. Like the ThreadPool, a task does not create its own OS thread. Instead, tasks are executed by a TaskScheduler; the default scheduler simply runs on the ThreadPool.

Unlike the ThreadPool, Task also allows you to find out when it finishes, and (via the generic Task) to return a result. You can call ContinueWith() on an existing Task to make it run more code once the task finishes (if it's already finished, it will run the callback immediately). If the task is generic, ContinueWith() will pass you the task's result, allowing you to run more code that uses it.

You can also synchronously wait for a task to finish by calling Wait() (or, for a generic task, by getting the Result property). Like Thread.Join(), this will block the calling thread until the task finishes. Synchronously waiting for a task is usually bad idea; it prevents the calling thread from doing any other work, and can also lead to deadlocks if the task ends up waiting (even asynchronously) for the current thread.

Since tasks still run on the ThreadPool, they should not be used for long-running operations, since they can still fill up the thread pool and block new work. Instead, Task provides a LongRunning option, which will tell the TaskScheduler to spin up a new thread rather than running on the ThreadPool.

All newer high-level concurrency APIs, including the Parallel.For*() methods, PLINQ, C# 5 await, and modern async methods in the BCL, are all built on Task.

Conclusion

The bottom line is that Task is almost always the best option; it provides a much more powerful API and avoids wasting OS threads.

The only reasons to explicitly create your own Threads in modern code are setting per-thread options, or maintaining a persistent thread that needs to maintain its own identity.

JQuery $.ajax() post - data in a java servlet

Simple method to sending data using java script and ajex call.

First right your form like this 

<form id="frm_details" method="post" name="frm_details">
<input  id="email" name="email" placeholder="Your Email id" type="text" />
    <button class="subscribe-box__btn" type="submit">Need Assistance</button>
</form>

javascript logic target on form id #frm_details after sumbit 

$(function(){
        $("#frm_details").on("submit", function(event) {
            event.preventDefault();

            var formData = {
                'email': $('input[name=email]').val() //for get email 
            };
            console.log(formData);

            $.ajax({
                url: "/tsmisc/api/subscribe-newsletter",
                type: "post",
                data: formData,
                success: function(d) {
                    alert(d);
                }
            });
        });
    }) 





General 
Request URL:https://test.abc
Request Method:POST
Status Code:200 
Remote Address:13.76.33.57:443

From Data
email:[email protected]

Reversing an Array in Java

 
 public void swap(int[] arr,int a,int b)
 {
    int temp=arr[a];
    arr[a]=arr[b];
    arr[b]=temp;        
}
public int[] reverseArray(int[] arr){
    int size=arr.length-1;

    for(int i=0;i<size;i++){

        swap(arr,i,size--); 

    }

    return arr;
}

Set an environment variable in git bash

If you want to set environment variables permanently in Git-Bash, you have two options:

  1. Set a regular Windows environment variable. Git-bash gets all existing Windows environment variables at startupp.

  2. Set up env variables in .bash_profile file.

.bash_profile is by default located in a user home folder, like C:\users\userName\git-home\.bash_profile. You can change the path to the bash home folder by setting HOME Windows environment variable.

.bash_profile file uses the regular Bash syntax and commands

# Export a variable in .bash_profile
export DIR=c:\dir
# Nix path style works too
export DIR=/c/dir

# And don't forget to add quotes if a variable contains whitespaces
export ANOTHER_DIR="c:\some dir"

Read more information about Bash configurations files.

How can I clear the terminal in Visual Studio Code?

Go to

  1. File >Preferences >Keyboard shortcuts.
  2. Search for "Terminal: clear"
  3. By default no keyboard shortcut is assigned.
  4. Just click on the Plus (+)icon in the banner and give the preferred shortcut of your choice to clear the terminal.
  5. I prefer to use ctrl+k as that shortcut is not assigned with any command.

Rounded Corners Image in Flutter

you can use ClipRRect like this :

  Padding(
                  padding: const EdgeInsets.all(8.0),
                  child: ClipRRect(
                    borderRadius: BorderRadius.circular(25),
                    child: Image.asset(
                      'assets/images/pic13.jpeg',
                      fit: BoxFit.cover,
                    ),
                  ),
                )

you can set your radius, or user for only for topLeft or bottom left like :

Padding(
              padding: const EdgeInsets.all(8.0),
              child: ClipRRect(
                borderRadius: BorderRadius.only(
                    topLeft: Radius.circular(25)
                ,bottomLeft: Radius.circular(25)),
                child: Image.asset(
                  'assets/images/pic13.jpeg',
                  fit: BoxFit.cover,
                ),
              ),
            )

How to allow Cross domain request in apache2

 
OS=GNU/Linux Debian
Httpd=Apache/2.4.10

Change in /etc/apache2/apache2.conf

<Directory /var/www/html>
     Order Allow,Deny
     Allow from all
     AllowOverride all
     Header set Access-Control-Allow-Origin "*"
</Directory>

Add/activate module

 a2enmod headers

Restart service

/etc/init.d/apache2 restart

How do I fix the multiple-step OLE DB operation errors in SSIS?

Also check if the script has no batch seperator commands (remove the 'GO' statements on a single line).

Android, How can I Convert String to Date?

 
     import java.text.ParseException;
     import java.text.SimpleDateFormat;
     import java.util.Date;
     public class MyClass 
     {
     public static void main(String args[]) 
     {
     SimpleDateFormat formatter = new SimpleDateFormat("EEE MMM dd HH:mm:ss Z yyyy");

     String dateInString = "Wed Mar 14 15:30:00 EET 2018";

     SimpleDateFormat formatterOut = new SimpleDateFormat("dd MMM yyyy");


     try {

        Date date = formatter.parse(dateInString);
        System.out.println(date);
        System.out.println(formatterOut.format(date));

         } catch (ParseException e) {
        e.printStackTrace();
         }
    }
    }

here is your Date object date and the output is :

Wed Mar 14 13:30:00 UTC 2018

14 Mar 2018

Creating a comma separated list from IList<string> or IEnumerable<string>

I think that the cleanest way to create a comma-separated list of string values is simply:

string.Join<string>(",", stringEnumerable);

Here is a full example:

IEnumerable<string> stringEnumerable= new List<string>();
stringList.Add("Comma");
stringList.Add("Separated");

string.Join<string>(",", stringEnumerable);

There is no need to make a helper function, this is built into .NET 4.0 and above.

Is it possible to run .APK/Android apps on iPad/iPhone devices?

It is not natively possible to run Android application under iOS (which powers iPhone, iPad, iPod, etc.)

This is because both runtime stacks use entirely different approaches. Android runs Dalvik (a "variant of Java") bytecode packaged in APK files while iOS runs Compiled (from Obj-C) code from IPA files. Excepting time/effort/money and litigations (!), there is nothing inherently preventing an Android implementation on Apple hardware, however.

It looks to package a small Dalvik VM with each application and targeted towards developers.

See iPhoDroid:

Looks to be a dual-boot solution for 2G/3G jailbroken devices. Very little information available, but there are some YouTube videos.

See iAndroid:

iAndroid is a new iOS application for jailbroken devices that simulates the Android operating system experience on the iPhone or iPod touch. While it’s still very far from completion, the project is taking shape.

I am not sure the approach(es) it uses to enable this: it could be emulation or just a simulation (e.g. "looks like"). The requirement of being jailbroken makes it sound like emulation might be used ..

See BlueStacks, per the Holo Dev's comment:

It looks to be an "Android App Player" for OS X (and Windows). However, afaik, it does not [currently] target iOS devices ..

YMMV

java.lang.ClassNotFoundException: org.eclipse.core.runtime.adaptor.EclipseStarter

check jar files in your project which are mentioned in config.ini if not proper then install manually and then follow the following steps:

  1. Select your product configuration file, right-click on it and select Run As Run Configurations
  2. Select "Validate plug-ins prior to launching". This will check if you have all required plug-ins in your run configuration. If this check reports that some plug-ins are missing, try clicking the "Add Required-Plug-Ins" button. Also make sure to define all dependencies in your product. And your application start running

How do you load custom UITableViewCells from Xib files?

Check this - http://eppz.eu/blog/custom-uitableview-cell/ - really convenient way using a tiny class that ends up one line in controller implementation:

-(UITableViewCell*)tableView:(UITableView*) tableView cellForRowAtIndexPath:(NSIndexPath*) indexPath
{
    return [TCItemCell cellForTableView:tableView
                          atIndexPath:indexPath
                      withModelSource:self];
}

enter image description here

Select current element in jQuery

Fortunately, jQuery selectors allow you much more freedom:

$("div a").click( function(event)
{
   var clicked = $(this); // jQuery wrapper for clicked element
   // ... click-specific code goes here ...
});

...will attach the specified callback to each <a> contained in a <div>.

How do I count unique visitors to my site?

Unique views is always a hard nut to crack. Checking the IP might work, but an IP can be shared by more than one user. A cookie could be a viable option, but a cookie can expire or be modified by the client.

In your case, it don't seem to be a big issue if the cookie is modified tho, so i would recommend using a cookie in a case like this. When the page is loaded, check if there is a cookie, if there is not, create one and add a +1 to views. If it is set, don't do the +1.

Set the cookies expiration date to whatever you want it to be, week or day if that's what you want, and it will expire after that time. After expiration, it will be a unique user again!

Edit:
Thought it might be a good idea to add this notice here...
Since around the end of 2016 a IP address (static or dynamic) is seen as personal data in the EU.
That means that you are only allowed to store a IP address with a good reason (and I'm not sure if tracking views is a good reason). So if you intend to store the IP address of visitors, I would recommend hashing or encrypting it with a algorithm which can not be reversed, to make sure that you are not breaching any law (especially after the GDPR laws have been implemented).

How can I add to a List's first position?

You do that by inserting into position 0:

List myList = new List();
myList.Insert(0, "test");

How can I add C++11 support to Code::Blocks compiler?

The answer with screenshots (put the checkbox as in the second pic, then press OK):

enter image description here enter image description here

Switching users inside Docker image to a non-root user

In case you need to perform privileged tasks like changing permissions of folders you can perform those tasks as a root user and then create a non-privileged user and switch to it:

From <some-base-image:tag>

# Switch to root user
USER root # <--- Usually you won't be needed it - Depends on base image

# Run privileged command
RUN apt install <packages>
RUN apt <privileged command>

# Set user and group
ARG user=appuser
ARG group=appuser
ARG uid=1000
ARG gid=1000
RUN groupadd -g ${gid} ${group}
RUN useradd -u ${uid} -g ${group} -s /bin/sh -m ${user} # <--- the '-m' create a user home directory

# Switch to user
USER ${uid}:${gid}

# Run non-privileged command
RUN apt <non-privileged command>

What happened to the .pull-left and .pull-right classes in Bootstrap 4?

Changed to float-right float-left float-xx-left and float-xx-right

Simple Random Samples from a Sql database

If you need exactly m rows, realistically you'll generate your subset of IDs outside of SQL. Most methods require at some point to select the "nth" entry, and SQL tables are really not arrays at all. The assumption that the keys are consecutive in order to just join random ints between 1 and the count is also difficult to satisfy — MySQL for example doesn't support it natively, and the lock conditions are... tricky.

Here's an O(max(n, m lg n))-time, O(n)-space solution assuming just plain BTREE keys:

  1. Fetch all values of the key column of the data table in any order into an array in your favorite scripting language in O(n)
  2. Perform a Fisher-Yates shuffle, stopping after m swaps, and extract the subarray [0:m-1] in ?(m)
  3. "Join" the subarray with the original dataset (e.g. SELECT ... WHERE id IN (<subarray>)) in O(m lg n)

Any method that generates the random subset outside of SQL must have at least this complexity. The join can't be any faster than O(m lg n) with BTREE (so O(m) claims are fantasy for most engines) and the shuffle is bounded below n and m lg n and doesn't affect the asymptotic behavior.

In Pythonic pseudocode:

ids = sql.query('SELECT id FROM t')
for i in range(m):
  r = int(random() * (len(ids) - i))
  ids[i], ids[i + r] = ids[i + r], ids[i]

results = sql.query('SELECT * FROM t WHERE id IN (%s)' % ', '.join(ids[0:m-1])

How to convert a multipart file to File?

MultipartFile.transferTo(File) is nice, but don't forget to clean the temp file after all.

// ask JVM to ask operating system to create temp file
File tempFile = File.createTempFile(TEMP_FILE_PREFIX, TEMP_FILE_POSTFIX);

// ask JVM to delete it upon JVM exit if you forgot / can't delete due exception
tempFile.deleteOnExit();

// transfer MultipartFile to File
multipartFile.transferTo(tempFile);

// do business logic here
result = businessLogic(tempFile);

// tidy up
tempFile.delete();

Check out Razzlero's comment about File.deleteOnExit() executed upon JVM exit (which may be extremely rare) details below.

Check if specific input file is empty

 
 if( ($_POST) && (!empty($_POST['cover_image'])) )    //verifies  if post exists and cover_image is not empty
    {
    //execute whatever code you want
    }

Excel formula to reference 'CELL TO THE LEFT'

When creating your conditional formatting, set the range to which it applies to what you want (the whole sheet), then enter a relative formula (remove the $ signs) as if you were only formatting the upper-left corner.

Excel will properly apply the formatting to the rest of the cells accordingly.

In this example, starting in B1, the left cell would be A1. Just use that--no advanced formula required.

If you're looking for something more advanced, you can play around with column(), row(), and indirect(...).

need to add a class to an element

You should be using className

result.className = "red"

Python 2.7: %d, %s, and float()

See String Formatting Operations:

%d is the format code for an integer. %f is the format code for a float.

%s prints the str() of an object (What you see when you print(object)).

%r prints the repr() of an object (What you see when you print(repr(object)).

For a float %s, %r and %f all display the same value, but that isn't the case for all objects. The other fields of a format specifier work differently as well:

>>> print('%10.2s' % 1.123) # print as string, truncate to 2 characters in a 10-place field.
        1.
>>> print('%10.2f' % 1.123) # print as float, round to 2 decimal places in a 10-place field.
      1.12

How can prepared statements protect from SQL injection attacks?

I read through the answers and still felt the need to stress the key point which illuminates the essence of Prepared Statements. Consider two ways to query one's database where user input is involved:

Naive Approach

One concatenates user input with some partial SQL string to generate a SQL statement. In this case the user can embed malicious SQL commands, which will then be sent to the database for execution.

String SQLString = "SELECT * FROM CUSTOMERS WHERE NAME='"+userInput+"'"

For example, malicious user input can lead to SQLString being equal to "SELECT * FROM CUSTOMERS WHERE NAME='James';DROP TABLE CUSTOMERS;'

Due to the malicious user, SQLString contains 2 statements, where the 2nd one ("DROP TABLE CUSTOMERS") will cause harm.

Prepared Statements

In this case, due to the separation of the query & data, the user input is never treated as a SQL statement, and thus is never executed. It is for this reason, that any malicious SQL code injected would cause no harm. So the "DROP TABLE CUSTOMERS" would never be executed in the case above.

In a nutshell, with prepared statements malicious code introduced via user input will not be executed!

proper name for python * operator?

I call *args "star args" or "varargs" and **kwargs "keyword args".

How do I make a semi transparent background?

If you want to make transparent background is gray, pls try:

   .transparent{
       background:rgba(1,1,1,0.5);
   }

How to write character & in android strings.xml

Mac and Android studio users:

Type your char such as & in the string.xml or layout and choose "Option" and "return" keys. Please refer the screen shot

What is difference between Lightsail and EC2?

Testing¹ reveals that Lightsail instances in fact are EC2 instances, from the t2 class of burstable instances.

EC2, of course, has many more instance families and classes other than the t2, almost all of which are more "powerful" (or better equipped for certain tasks) than these, but also much more expensive. But for meaningful comparisons, the 512 MiB Lightsail instance appears to be completely equivalent in specifications to the similarly-priced t2.nano, the 1GiB is a t2.micro, the 2 GiB is a t2.small, etc.

Lightsail is a lightweight, simplified product offering -- hard disks are fixed size EBS SSD volumes, instances are still billable when stopped, security group rules are much less flexible, and only a very limited subset of EC2 features and options are accessible.

It also has a dramatically simplified console, and even though the machines run in EC2, you can't see them in the EC2 section of the AWS console. The instances run in a special VPC, but this aspect is also provisioned automatically, and invisible in the console. Lightsail supports optionally peering this hidden VPC with your default VPC in the same AWS region, allowing Lightsail instances to access services like EC2 and RDS in the default VPC within the same AWS account.²

Bandwidth is unlimited, but of course free bandwidth is not -- however, Lightsail instances do include a significant monthly bandwidth allowance before any bandwidth-related charges apply.³ Lightsail also has a simplified interface to Route 53 with limited functionality.

But if those sound like drawbacks, they aren't. The point of Lightsail seems to be simplicity. The flexibility of EC2 (and much of AWS) leads inevitably to complexity. The target market for Lightsail appears to be those who "just want a simple VPS" without having to navigate the myriad options available in AWS services like EC2, EBS, VPC, and Route 53. There is virtually no learning curve, here. You don't even technically need to know how to use SSH with a private key -- the Lightsail console even has a built-in SSH client -- but there is no requirement that you use it. You can access these instances normally, with a standard SSH client.

¹Lightsail instances, just like "regular" EC2 (VPC and Classic) instances, have access to the instance metadata service, which allows an instance to discover things about itself, such as its instance type and availability zone. Lightsail instances are identified in the instance metadata as t2 machines.

²The Lightsail docs are not explicit about the fact that peering only works with your Default VPC, but this appears to be the case. If your AWS account was created in 2013 or before, then you may not actually have a VPC with the "Default VPC" designation. This can be resolved by submitting a support request, as I explained in Can't establish VPC peering connection from Amazon Lightsail (at Server Fault).

³The bandwidth allowance applies to both inbound and outbound traffic; after this total amount of traffic is exceeded, inbound traffic continues to be free, but outbound traffic becomes billable. See "What does data transfer cost?" in the Lightsail FAQ.

How to make a smooth image rotation in Android?

This works fine

<?xml version="1.0" encoding="UTF-8"?>
<rotate xmlns:android="http://schemas.android.com/apk/res/android"
    android:duration="1600"
    android:fromDegrees="0"
    android:interpolator="@android:anim/linear_interpolator"
    android:pivotX="50%"
    android:pivotY="50%"
    android:repeatCount="infinite"
    android:toDegrees="358" />

To reverse rotate:

<?xml version="1.0" encoding="UTF-8"?>
<rotate xmlns:android="http://schemas.android.com/apk/res/android"
    android:duration="1600"
    android:fromDegrees="358"
    android:interpolator="@android:anim/linear_interpolator"
    android:pivotX="50%"
    android:pivotY="50%"
    android:repeatCount="infinite"
    android:toDegrees="0" />

SQL Inner join 2 tables with multiple column conditions and update

You should join T1 and T2 tables using sql joins in order to analyze from two tables. Link for learn joins : https://www.w3schools.com/sql/sql_join.asp

User Control - Custom Properties

You do this via attributes on the properties, like this:

[Description("Test text displayed in the textbox"),Category("Data")] 
public string Text {
  get => myInnerTextBox.Text;
  set => myInnerTextBox.Text = value;
}

The category is the heading under which the property will appear in the Visual Studio Properties box. Here's a more complete MSDN reference, including a list of categories.

Removing duplicates from a String in Java

 
public static void main(String[] args) {

    int i,j;
    StringBuffer str=new StringBuffer();
    Scanner in = new Scanner(System.in);
    System.out.print("Enter string: ");

    str.append(in.nextLine());

    for (i=0;i<str.length()-1;i++)
    {
        for (j=1;j<str.length();j++)
        {
            if (str.charAt(i)==str.charAt(j))
                str.deleteCharAt(j);
        }
    }
    System.out.println("Removed String: " + str);
}

How do I check if a string contains another string in Objective-C?

If you need this once write:

NSString *stringToSearchThrough = @"-rangeOfString method finds and returns the range of the first occurrence of a given string within the receiver.";
BOOL contains = [stringToSearchThrough rangeOfString:@"occurence of a given string"].location != NSNotFound;

Non-resolvable parent POM for Could not find artifact and 'parent.relativePath' points at wrong local POM

Any way you mentioned /root/.m2/settings.xml.

But in my Case i missed the settings.xml to configure in the maven preferences. enter image description here so that maven will search for the relative_path pom.xml from the remote_repository which is configured in settings.xml

How to execute two mysql queries as one in PHP/MYSQL?

As others have answered, the mysqli API can execute multi-queries with the msyqli_multi_query() function.

For what it's worth, PDO supports multi-query by default, and you can iterate over the multiple result sets of your multiple queries:

$stmt = $dbh->prepare("
    select sql_calc_found_rows * from foo limit 1 ; 
    select found_rows()");
$stmt->execute();
do {
  while ($row = $stmt->fetch()) {
    print_r($row);
  }
} while ($stmt->nextRowset());

However, multi-query is pretty widely considered a bad idea for security reasons. If you aren't careful about how you construct your query strings, you can actually get the exact type of SQL injection vulnerability shown in the classic "Little Bobby Tables" XKCD cartoon. When using an API that restrict you to single-query, that can't happen.

Check if Key Exists in NameValueCollection

I don't think any of these answers are quite right/optimal. NameValueCollection not only doesn't distinguish between null values and missing values, it's also case-insensitive with regards to it's keys. Thus, I think a full solution would be:

public static bool ContainsKey(this NameValueCollection @this, string key)
{
    return @this.Get(key) != null 
        // I'm using Keys instead of AllKeys because AllKeys, being a mutable array,
        // can get out-of-sync if mutated (it weirdly re-syncs when you modify the collection).
        // I'm also not 100% sure that OrdinalIgnoreCase is the right comparer to use here.
        // The MSDN docs only say that the "default" case-insensitive comparer is used
        // but it could be current culture or invariant culture
        || @this.Keys.Cast<string>().Contains(key, StringComparer.OrdinalIgnoreCase);
}

Rails: FATAL - Peer authentication failed for user (PG::Error)

Adding host: localhost was the magic for me

development:
  adapter: postgresql
  database: database_name_here
  host: localhost
  username: user_name_here

How to bundle vendor scripts separately and require them as needed with Webpack?

in my webpack.config.js (Version 1,2,3) file, I have

function isExternal(module) {
  var context = module.context;

  if (typeof context !== 'string') {
    return false;
  }

  return context.indexOf('node_modules') !== -1;
}

in my plugins array

plugins: [
  new CommonsChunkPlugin({
    name: 'vendors',
    minChunks: function(module) {
      return isExternal(module);
    }
  }),
  // Other plugins
]

Now I have a file that only adds 3rd party libs to one file as required.

If you want get more granular where you separate your vendors and entry point files:

plugins: [
  new CommonsChunkPlugin({
    name: 'common',
    minChunks: function(module, count) {
      return !isExternal(module) && count >= 2; // adjustable
    }
  }),
  new CommonsChunkPlugin({
    name: 'vendors',
    chunks: ['common'],
    // or if you have an key value object for your entries
    // chunks: Object.keys(entry).concat('common')
    minChunks: function(module) {
      return isExternal(module);
    }
  })
]

Note that the order of the plugins matters a lot.

Also, this is going to change in version 4. When that's official, I update this answer.

Update: indexOf search change for windows users

.Net System.Mail.Message adding multiple "To" addresses

Put in addresses this code:

objMessage.To.Add(***addresses:=***"[email protected] , [email protected] , [email protected]")

What is @RenderSection in asp.net MVC

Suppose if I have GetAllEmployees.cshtml

<h2>GetAllEmployees</h2>

<p>
    <a asp-action="Create">Create New</a>
</p>
<table class="table">
    <thead>
         // do something ...
    </thead>
    <tbody>
       // do something ...
    </tbody>
</table>

   //Added my custom scripts in the scripts sections

@section Scripts
    {
    <script src="~/js/customScripts.js"></script>
    }

And another view "GetEmployeeDetails.cshtml" with no scripts

<h2>GetEmployeeByDetails</h2>

@Model.PageTitle
<p>
    <a asp-action="Create">Create New</a>
</p>
<table class="table">
    <thead>
       // do something ... 
    </thead>
    <tbody>
       // do something ...
    </tbody>
</table>

And my layout page "_layout.cshtml"

@RenderSection("Scripts", required: true)

So, when I navigate to GetEmployeeDetails.cshtml. I get the error that there is no section scripts to be rendered in GetEmployeeDetails.cshtml. If I change the flag in @RenderSection() from required : true to ``required : false`. It means render the scripts defined in the @section scripts of the views if present.Else, do nothing. And the refined approach would be in _layout.cshtml

@if (IsSectionDefined("Scripts"))
    {
        @RenderSection("Scripts", required: true)
    }

Setting dropdownlist selecteditem programmatically

 
var index = ctx.Items.FirstOrDefault(item => Equals(item.Value, Settings.Default.Format_Encoding));
ctx.SelectedIndex = ctx.Items.IndexOf(index);

OR

foreach (var listItem in ctx.Items)
  listItem.Selected = Equals(listItem.Value as Encoding, Settings.Default.Format_Encoding);

Should work.. especially when using extended RAD controls in which FindByText/Value doesn't even exist!

how to properly display an iFrame in mobile safari

If the iFrame content is not yours then the solution below will not work.

With Android all you need to do is to surround the iframe with a DIV and set the height on the div to document.documentElement.clientHeight. IOS, however, is a different animal. Although I have not yet tried Sharon's solution it does seem like a good solution. I did find a simpler solution but it only works with IOS 5.+.

Surround your iframe element with a DIV (lets call it scroller), set the height of the DIV and make sure that the new DIV has the following styling:

$('#scroller').css({'overflow' : 'auto', '-webkit-overflow-scrolling' : 'touch'});

This alone will work but you will notice that in most implementations the content in the iframe goes blank when scrolling and is basically rendered useless. My understanding is that this behavior has been reported as a bug to Apple as early as iOS 5.0. To get around that problem, find the body element in the iframe and add -webkit-transform', 'translate3d(0, 0, 0) like so:

$('#contentIframe').contents().find('body').css('-webkit-transform', 'translate3d(0, 0, 0)');

If your app or iframe is heavy on memory usage you might get a hitchy scroll for which you might need to use Sharon's solution.

How can I get the current date and time in UTC or GMT in Java?

If you want a Date object with fields adjusted for UTC you can do it like this with Joda Time:

import org.joda.time.DateTimeZone;
import java.util.Date;

...

Date local = new Date();
System.out.println("Local: " + local);
DateTimeZone zone = DateTimeZone.getDefault();
long utc = zone.convertLocalToUTC(local.getTime(), false);
System.out.println("UTC: " + new Date(utc));

Time complexity of Euclid's Algorithm

There's a great look at this on the wikipedia article.

It even has a nice plot of complexity for value pairs.

It is not O(a%b).

It is known (see article) that it will never take more steps than five times the number of digits in the smaller number. So the max number of steps grows as the number of digits (ln b). The cost of each step also grows as the number of digits, so the complexity is bound by O(ln^2 b) where b is the smaller number. That's an upper limit, and the actual time is usually less.

Merge two json/javascript arrays in to one array

 
var json1=["Chennai","Bangalore"];
var json2=["TamilNadu","Karanataka"];

finaljson=json1.concat(json2);

What's a decent SFTP command-line client for windows?

This little application does the job for me. I could not find another CLI based client that would access my IIS based TLS/SSL secured ftp site: http://netwinsite.com/surgeftp/sslftp.htm

Check if string contains only letters in javascript

With /^[a-zA-Z]/ you only check the first character:

  • ^: Assert position at the beginning of the string
  • [a-zA-Z]: Match a single character present in the list below:
    • a-z: A character in the range between "a" and "z"
    • A-Z: A character in the range between "A" and "Z"

If you want to check if all characters are letters, use this instead:

/^[a-zA-Z]+$/.test(str);
  • ^: Assert position at the beginning of the string
  • [a-zA-Z]: Match a single character present in the list below:
    • +: Between one and unlimited times, as many as possible, giving back as needed (greedy)
    • a-z: A character in the range between "a" and "z"
    • A-Z: A character in the range between "A" and "Z"
  • $: Assert position at the end of the string (or before the line break at the end of the string, if any)

Or, using the case-insensitive flag i, you could simplify it to

/^[a-z]+$/i.test(str);

Or, since you only want to test, and not match, you could check for the opposite, and negate it:

!/[^a-z]/i.test(str);

whitespaces in the path of windows filepath

 
path = r"C:\Users\mememe\Google Drive\Programs\Python\file.csv"

Closing the path in r"string" also solved this problem very well.

"replace" function examples

Here's two simple examples

> x <- letters[1:4]
> replace(x, 3, 'Z') #replacing 'c' by 'Z'
[1] "a" "b" "Z" "d"
> 
> y <- 1:10
> replace(y, c(4,5), c(20,30)) # replacing 4th and 5th elements by 20 and 30
 [1]  1  2  3 20 30  6  7  8  9 10

Python: 'break' outside loop

This is an old question, but if you wanted to break out of an if statement, you could do:

while 1:
    if blah:
        break

How to delete Certain Characters in a excel 2010 cell

Replace [ with nothing, then ] with nothing.

How to export JSON from MongoDB using Robomongo

A Quick and dirty way: Just write your query as db.getCollection('collection').find({}).toArray() and right click Copy JSON. Paste the data in the editor of your choice.

enter image description here

Why did I get the compile error "Use of unassigned local variable"?

A very dummy mistake, but you can get this with a class too if you didn't instantiate it.

BankAccount account;
account.addMoney(5);

The above will produce the same error whereas:

class BankAccount
{
    int balance = 0;
    public void addMoney(int amount)
    {
        balance += amount;
    }
}

Do the following to eliminate the error:

BankAccount account = new BankAccount();
account.addMoney(5);

Split Strings into words with multiple word boundary delimiters

I had to come up with my own solution since everything I've tested so far failed at some point.

>>> import re
>>> def split_words(text):
...     rgx = re.compile(r"((?:(?<!'|\w)(?:\w-?'?)+(?<!-))|(?:(?<='|\w)(?:\w-?'?)+(?=')))")
...     return rgx.findall(text)

It seems to be working fine, at least for the examples below.

>>> split_words("The hill-tops gleam in morning's spring.")
['The', 'hill-tops', 'gleam', 'in', "morning's", 'spring']
>>> split_words("I'd say it's James' 'time'.")
["I'd", 'say', "it's", "James'", 'time']
>>> split_words("tic-tac-toe's tic-tac-toe'll tic-tac'tic-tac we'll--if tic-tac")
["tic-tac-toe's", "tic-tac-toe'll", "tic-tac'tic-tac", "we'll", 'if', 'tic-tac']
>>> split_words("google.com [email protected] split_words")
['google', 'com', 'email', 'google', 'com', 'split_words']
>>> split_words("Kurt Friedrich Gödel (/'g??rd?l/;[2] German: ['k???t 'gø?dl?] (listen);")
['Kurt', 'Friedrich', 'Gödel', ''g??rd?l', '2', 'German', ''k??', 't', ''gø?dl', 'listen']
>>> split_words("April 28, 1906 – January 14, 1978) was an Austro-Hungarian-born Austrian...")
['April', '28', '1906', 'January', '14', '1978', 'was', 'an', 'Austro-Hungarian-born', 'Austrian']

How to build minified and uncompressed bundle with webpack?

You should export an array like this:

const path = require('path');
const webpack = require('webpack');

const libName = 'YourLibraryName';

function getConfig(env) {
  const config = {
    mode: env,
    output: {
      path: path.resolve('dist'),
      library: libName,
      libraryTarget: 'umd',
      filename: env === 'production' ? `${libName}.min.js` : `${libName}.js`
    },
    target: 'web',
    .... your shared options ...
  };

  return config;
}

module.exports = [
  getConfig('development'),
  getConfig('production'),
];

Resize image proportionally with MaxHeight and MaxWidth constraints

Like this?

public static void Test()
{
    using (var image = Image.FromFile(@"c:\logo.png"))
    using (var newImage = ScaleImage(image, 300, 400))
    {
        newImage.Save(@"c:\test.png", ImageFormat.Png);
    }
}

public static Image ScaleImage(Image image, int maxWidth, int maxHeight)
{
    var ratioX = (double)maxWidth / image.Width;
    var ratioY = (double)maxHeight / image.Height;
    var ratio = Math.Min(ratioX, ratioY);

    var newWidth = (int)(image.Width * ratio);
    var newHeight = (int)(image.Height * ratio);

    var newImage = new Bitmap(newWidth, newHeight);

    using (var graphics = Graphics.FromImage(newImage))
        graphics.DrawImage(image, 0, 0, newWidth, newHeight);

    return newImage;
}

Giving graphs a subtitle in matplotlib

Although this doesn't give you the flexibility associated with multiple font sizes, adding a newline character to your pyplot.title() string can be a simple solution;

plt.title('Really Important Plot\nThis is why it is important')

Install an apk file from command prompt?

You can build on the command line with ant. See this guide.

Then, you can install it by using adb on the command line.

adb install -r MyApp.apk

The -r flag is to replace the existing application.

Inserting a tab character into text using C#

It can also be useful to use String.Format, e.g.

String.Format("{0}\t{1}", FirstName,Count);

.NET Events - What are object sender & EventArgs e?

Manually cast the sender to the type of your custom control, and then use it to delete or disable etc. Eg, something like this:

private void myCustomControl_Click(object sender, EventArgs e)
{
  ((MyCustomControl)sender).DoWhatever();
}

The 'sender' is just the object that was actioned (eg clicked).

The event args is subclassed for more complex controls, eg a treeview, so that you can know more details about the event, eg exactly where they clicked.

jQuery: Can I call delay() between addClass() and such?

I know this this is a very old post but I've combined a few of the answers into a jQuery wrapper function that supports chaining. Hope it benefits someone:

$.fn.queueAddClass = function(className) {
    this.queue('fx', function(next) {
        $(this).addClass(className);
        next();
    });
    return this;
};

And here's a removeClass wrapper:

$.fn.queueRemoveClass = function(className) {
    this.queue('fx', function(next) {
        $(this).removeClass(className);
        next();
    });
    return this;
};

Now you can do stuff like this - wait 1sec, add .error, wait 3secs, remove .error:

$('#div').delay(1000).queueAddClass('error').delay(2000).queueRemoveClass('error');

Center an item with position: relative

You can use calc to position element relative to center. For example if you want to position element 200px right from the center .. you can do this :

#your_element{
    position:absolute;
    left: calc(50% + 200px);
}

Dont forget this

When you use signs + and - you must have one blank space between sign and number, but when you use signs * and / there is no need for blank space.

How do you add PostgreSQL Driver as a dependency in Maven?

 
<dependency>
    <groupId>org.postgresql</groupId>
    <artifactId>postgresql</artifactId>
    <scope>runtime</scope>
</dependency>

How can I remove "\r\n" from a string in C#? Can I use a regular expression?

Here is the perfect method:

Please note that Environment.NewLine works on on Microsoft platforms.

In addition to the above, you need to add \r and \n in a separate function!

Here is the code which will support whether you type on Linux, Windows, or Mac:

var stringTest = "\r Test\nThe Quick\r\n brown fox";

Console.WriteLine("Original is:");
Console.WriteLine(stringTest);
Console.WriteLine("-------------");

stringTest = stringTest.Trim().Replace("\r", string.Empty);
stringTest = stringTest.Trim().Replace("\n", string.Empty);
stringTest = stringTest.Replace(Environment.NewLine, string.Empty);

Console.WriteLine("Output is : ");
Console.WriteLine(stringTest);
Console.ReadLine();

How do I make an HTML button not reload the page

In HTML:

<input type="submit" onclick="return false">

With jQuery, some similar variant, already mentioned.

How to implement common bash idioms in Python?

I just discovered how to combine the best parts of bash and ipython. Up to now this seems more comfortable to me than using subprocess and so on. You can easily copy big parts of existing bash scripts and e.g. add error handling in the python way :) And here is my result:

#!/usr/bin/env ipython3

# *** How to have the most comfort scripting experience of your life ***
# ######################################################################
#
# … by using ipython for scripting combined with subcommands from bash!
#
# 1. echo "#!/usr/bin/env ipython3" > scriptname.ipy    # creates new ipy-file
#
# 2. chmod +x scriptname.ipy                            # make in executable
#
# 3. starting with line 2, write normal python or do some of
#    the ! magic of ipython, so that you can use unix commands
#    within python and even assign their output to a variable via
#    var = !cmd1 | cmd2 | cmd3                          # enjoy ;)
#
# 4. run via ./scriptname.ipy - if it fails with recognizing % and !
#    but parses raw python fine, please check again for the .ipy suffix

# ugly example, please go and find more in the wild
files = !ls *.* | grep "y"
for file in files:
  !echo $file | grep "p"
# sorry for this nonsense example ;)

See IPython docs on system shell commands and using it as a system shell.

What is SELF JOIN and when would you use it?

You'd use a self-join on a table that "refers" to itself - e.g. a table of employees where managerid is a foreign-key to employeeid on that same table.

Example:

SELECT E.name, ME.name AS manager
FROM dbo.Employees E
LEFT JOIN dbo.Employees ME
ON ME.employeeid = E.managerid

How do I add FTP support to Eclipse?

Install Aptana plugin to your Eclipse installation.

It has built-in FTP support, and it works excellently.

You can:

  • Edit files directly from the FTP server
  • Perform file/folder management (copy, delete, move, rename, etc.)
  • Upload/download files to/from FTP server
  • Synchronize local files with FTP server. You can make several profiles (actually projects) for this so you won't have to reinput over and over again.

As a matter of fact the FTP support is so good I'm using Aptana (or Eclipse + Aptana) now for all my FTP needs. Plus I get syntax highlighting/whatever coding support there is. Granted, Eclipse is not the speediest app to launch, but it doesn't bug me so much.

How to compare if two structs, slices or maps are equal?

If you're comparing them in unit test, a handy alternative is EqualValues function in testify.

Error retrieving parent for item: No resource found that matches the given name 'android:TextAppearance.Material.Widget.Button.Borderless.Colored'

in my case i was using compile sdk 23 and build tools 25.0.0 just changed compile sdk to 25 and done..

How do I compare two DateTime objects in PHP 5.2.8?

As of PHP 7.x, you can use the following:

$aDate = new \DateTime('@'.(time()));
$bDate = new \DateTime('@'.(time() - 3600));

$aDate <=> $bDate; // => 1, `$aDate` is newer than `$bDate`

Is there a way to iterate over a dictionary?

Yes, NSDictionary supports fast enumeration. With Objective-C 2.0, you can do this:

// To print out all key-value pairs in the NSDictionary myDict
for(id key in myDict)
    NSLog(@"key=%@ value=%@", key, [myDict objectForKey:key]);

The alternate method (which you have to use if you're targeting Mac OS X pre-10.5, but you can still use on 10.5 and iPhone) is to use an NSEnumerator:

NSEnumerator *enumerator = [myDict keyEnumerator];
id key;
// extra parens to suppress warning about using = instead of ==
while((key = [enumerator nextObject]))
    NSLog(@"key=%@ value=%@", key, [myDict objectForKey:key]);

Get value from text area

 
$('textarea').val();

textarea.value would be pure JavaScript, but here you're trying to use JavaScript as a not-valid jQuery method (.value).

INSTALL_FAILED_DUPLICATE_PERMISSION... C2D_MESSAGE

See this link it said that it will work when they are signed by the same key. The release key and the debug key are not the same.

So do it:

buildTypes {
        release {
            minifyEnabled true
            signingConfig signingConfigs.release//signing by the same key
            proguardFiles getDefaultProguardFile('proguard-android.txt'), 'proguard-android.txt'

        }
        debug {
            applicationIdSuffix ".debug"
            debuggable true
            signingConfig signingConfigs.release//signing by the same key
        }

    }

 signingConfigs {
        release {
            storeFile file("***\\key_.jks")
            storePassword "key_***"
            keyAlias "key_***"
            keyPassword "key_"***"
        }


}

UL has margin on the left

I don't see any margin or margin-left declarations for #footer-wrap li.

This ought to do the trick:

#footer-wrap ul,
#footer-wrap li {
    margin-left: 0;
    list-style-type: none;
}

How to install numpy on windows using pip install?

Check installation of python 2.7 than install/reinstall pip which described here than open command line and write 

pip install numpy

or 

pip install scipy

if already installed try this

pip install -U numpy

Is module __file__ attribute absolute or relative?

With the help of the of Guido mail provided by @kindall, we can understand the standard import process as trying to find the module in each member of sys.path, and file as the result of this lookup (more details in PyMOTW Modules and Imports.). So if the module is located in an absolute path in sys.path the result is absolute, but if it is located in a relative path in sys.path the result is relative.

Now the site.py startup file takes care of delivering only absolute path in sys.path, except the initial '', so if you don't change it by other means than setting the PYTHONPATH (whose path are also made absolute, before prefixing sys.path), you will get always an absolute path, but when the module is accessed through the current directory.

Now if you trick sys.path in a funny way you can get anything.

As example if you have a sample module foo.py in /tmp/ with the code:

import sys
print(sys.path)
print (__file__)

If you go in /tmp you get:

>>> import foo
['', '/tmp', '/usr/lib/python3.3', ...]
./foo.py

When in in /home/user, if you add /tmp your PYTHONPATH you get:

>>> import foo
['', '/tmp', '/usr/lib/python3.3', ...]
/tmp/foo.py

Even if you add ../../tmp, it will be normalized and the result is the same.

But if instead of using PYTHONPATH you use directly some funny path you get a result as funny as the cause.

>>> import sys
>>> sys.path.append('../../tmp')
>>> import foo
['', '/usr/lib/python3.3', .... , '../../tmp']
../../tmp/foo.py

Guido explains in the above cited thread, why python do not try to transform all entries in absolute paths:

we don't want to have to call getpwd() on every import .... getpwd() is relatively slow and can sometimes fail outright,

So your path is used as it is.

Get size of an Iterable in Java

You can cast your iterable to a list then use .size() on it.

Lists.newArrayList(iterable).size();

For the sake of clarity, the above method will require the following import:

import com.google.common.collect.Lists;

How to remove files and directories quickly via terminal (bash shell)

Yes, there is. The -r option tells rm to be recursive, and remove the entire file hierarchy rooted at its arguments; in other words, if given a directory, it will remove all of its contents and then perform what is effectively an rmdir.

The other two options you should know are -i and -f. -i stands for interactive; it makes rm prompt you before deleting each and every file. -f stands for force; it goes ahead and deletes everything without asking. -i is safer, but -f is faster; only use it if you're absolutely sure you're deleting the right thing. You can specify these with -r or not; it's an independent setting.

And as usual, you can combine switches: rm -r -i is just rm -ri, and rm -r -f is rm -rf.

Also note that what you're learning applies to bash on every Unix OS: OS X, Linux, FreeBSD, etc. In fact, rm's syntax is the same in pretty much every shell on every Unix OS. OS X, under the hood, is really a BSD Unix system.

Search text in fields in every table of a MySQL database

This solution
a) is only MySQL, no other language needed, and
b) returns SQL results, ready for processing!

#Search multiple database tables and/or columns
#Version 0.1 - JK 2014-01
#USAGE: 1. set the search term @search, 2. set the scope by adapting the WHERE clause of the `information_schema`.`columns` query
#NOTE: This is a usage example and might be advanced by setting the scope through a variable, putting it all in a function, and so on...

#define the search term here (using rules for the LIKE command, e.g % as a wildcard)
SET @search = '%needle%';

#settings
SET SESSION group_concat_max_len := @@max_allowed_packet;

#ini variable
SET @sql = NULL;

#query for prepared statement
SELECT
    GROUP_CONCAT("SELECT '",`TABLE_NAME`,"' AS `table`, '",`COLUMN_NAME`,"' AS `column`, `",`COLUMN_NAME`,"` AS `value` FROM `",TABLE_NAME,"` WHERE `",COLUMN_NAME,"` LIKE '",@search,"'" SEPARATOR "\nUNION\n") AS col
INTO @sql
FROM `information_schema`.`columns`
WHERE TABLE_NAME IN
(
    SELECT TABLE_NAME FROM `information_schema`.`columns`
    WHERE
        TABLE_SCHEMA IN ("my_database")
        && TABLE_NAME IN ("my_table1", "my_table2") || TABLE_NAME LIKE "my_prefix_%"
);

#prepare and execute the statement
PREPARE stmt FROM @sql;
EXECUTE stmt;
DEALLOCATE PREPARE stmt;

How can I disable notices and warnings in PHP within the .htaccess file?

It is probably not the best thing to do. You need to at least check out your PHP error log for things going wrong ;)

# PHP error handling for development servers
php_flag display_startup_errors off
php_flag display_errors off
php_flag html_errors off
php_flag log_errors on
php_flag ignore_repeated_errors off
php_flag ignore_repeated_source off
php_flag report_memleaks on
php_flag track_errors on
php_value docref_root 0
php_value docref_ext 0
php_value error_log /home/path/public_html/domain/PHP_errors.log
php_value error_reporting -1
php_value log_errors_max_len 0

How do you normalize a file path in Bash?

A portable and reliable solution is to use python, which is preinstalled pretty much everywhere (including Darwin). You have two options:

  1. abspath returns an absolute path but does not resolve symlinks:

    python -c "import os,sys; print(os.path.abspath(sys.argv[1]))" path/to/file

  2. realpath returns an absolute path and in doing so resolves symlinks, generating a canonical path:

    python -c "import os,sys; print(os.path.realpath(sys.argv[1]))" path/to/file

In each case, path/to/file can be either a relative or absolute path.

How to find whether or not a variable is empty in Bash?

I have also seen

if [ "x$variable" = "x" ]; then ...

which is obviously very robust and shell independent.

Also, there is a difference between "empty" and "unset". See How to tell if a string is not defined in a Bash shell script.

CSS "and" and "or"

The :not pseudo-class is not supported by IE. I'd got for something like this instead:

.registration_form_right input[type="text"],
.registration_form_right input[type="password"],
.registration_form_right input[type="submit"],
.registration_form_right input[type="button"] {
  ...
}

Some duplication there, but it's a small price to pay for higher compatibility.

Giving height to table and row in Bootstrap

The simple solution that worked for me as below, wrap the table with a div and change the line-height, this line-height is taken as a ratio.

_x000D_
_x000D_ 
<div class="col-md-6" style="line-height: 0.5">_x000D_
                                <table class="table table-striped" >_x000D_
                                    <thead>_x000D_
                                    <tr>_x000D_
                                        <th>Parameter</th>_x000D_
                                        <th>Recorded Value</th>_x000D_
                                        <th>Individual Score</th>_x000D_
                                    </tr>_x000D_
                                    </thead>_x000D_
                                    <tbody>_x000D_
                                    <tr>_x000D_
                                        <td>Respiratory Rate</td>_x000D_
                                        <td>Doe</td>_x000D_
                                        <td>[email protected]</td>_x000D_
                                    </tr>_x000D_
                                    <tr>_x000D_
                                        <td>Respiratory Effort</td>_x000D_
                                        <td>Moe</td>_x000D_
                                        <td>[email protected]</td>_x000D_
                                    </tr>_x000D_
                                    <tr>_x000D_
                                        <td>Oxygon Saturation</td>_x000D_
                                        <td>Dooley</td>_x000D_
                                        <td>[email protected]</td>_x000D_
                                    </tr>_x000D_
                                    </tbody>_x000D_
                                </table>_x000D_
                            </div>
_x000D_
_x000D_
_x000D_

Try changing the value as it fits for you.

Java SimpleDateFormat for time zone with a colon separator?

if you used the java 7, you could have used the following Date Time Pattern. Seems like this pattern is not supported in the Earlier version of java.

String dateTimeString  = "2010-03-01T00:00:00-08:00";
DateFormat df = new SimpleDateFormat("yyyy-MM-dd'T'HH:mm:ssXXX");
Date date = df.parse(dateTimeString);

For More information refer to the SimpleDateFormat documentation.

Resolve promises one after another (i.e. in sequence)?

To do this simply in ES6:

function(files) {
  // Create a new empty promise (don't do that with real people ;)
  var sequence = Promise.resolve();

  // Loop over each file, and add on a promise to the
  // end of the 'sequence' promise.
  files.forEach(file => {

    // Chain one computation onto the sequence
    sequence = 
      sequence
        .then(() => performComputation(file))
        .then(result => doSomething(result)); 
        // Resolves for each file, one at a time.

  })

  // This will resolve after the entire chain is resolved
  return sequence;
}

Programmatically change the src of an img tag

 
<img src="../template/edit.png" name="edit-save" onclick="this.src = '../template/save.png'" />

Android studio - Failed to find target android-18

Thank you RobertoAV96.

You're my hero. But it's not enough. In my case, I changed both compileSdkVersion, and buildToolsVersion. Now it work. Hope this help

buildscript {
       repositories {
           mavenCentral()
       }
       dependencies {
          classpath 'com.android.tools.build:gradle:0.6.+'
       }
   }
   apply plugin: 'android'

   dependencies {
       compile fileTree(dir: 'libs', include: '*.jar')
   }

   android {
       compileSdkVersion 19
       buildToolsVersion "19"

       sourceSets {
           main {
               manifest.srcFile 'AndroidManifest.xml'
               java.srcDirs = ['src']
               resources.srcDirs = ['src']
               aidl.srcDirs = ['src']
               renderscript.srcDirs = ['src']
               res.srcDirs = ['res']
               assets.srcDirs = ['assets']
           }

           // Move the tests to tests/java, tests/res, etc...
           instrumentTest.setRoot('tests')
           // Move the build types to build-types/<type>
           // For instance, build-types/debug/java, build-types/debug/AndroidManifest.xml, ..
           // This moves them out of them default location under src/<type>/... which would
           // conflict with src/ being used by the main source set.
           // Adding new build types or product flavors should be accompanied
           // by a similar customization.
           debug.setRoot('build-types/debug')
           release.setRoot('build-types/release')
       }
   }

How to get Rails.logger printing to the console/stdout when running rspec?

For Rails 4.x the log level is configured a bit different than in Rails 3.x

Add this to config/environment/test.rb

# Enable stdout logger
config.logger = Logger.new(STDOUT)

# Set log level
config.log_level = :ERROR

The logger level is set on the logger instance from config.log_level at: https://github.com/rails/rails/blob/v4.2.4/railties/lib/rails/application/bootstrap.rb#L70

Environment variable

As a bonus, you can allow overwriting the log level using an environment variable with a default value like so:

# default :ERROR
config.log_level = ENV.fetch("LOG_LEVEL", "ERROR")

And then running tests from shell:

# Log level :INFO (the value is uppercased in bootstrap.rb)
$ LOG_LEVEL=info rake test

# Log level :ERROR
$ rake test

Convert Pandas Column to DateTime

If you have more than one column to be converted you can do the following:

df[["col1", "col2", "col3"]] = df[["col1", "col2", "col3"]].apply(pd.to_datetime)

How to get the HTML's input element of "file" type to only accept pdf files?

To get the HTML file input form element to only accept PDFs, you can use the accept attribute in modern browsers such as Firefox 9+, Chrome 16+, Opera 11+ and IE10+ like such:

<input name="file1" type="file" accept="application/pdf">

You can string together multiple mime types with a comma.

The following string will accept JPG, PNG, GIF, PDF, and EPS files:

<input name="foo" type="file" accept="image/jpeg,image/gif,image/png,application/pdf,image/x-eps">

In older browsers the native OS file dialog cannot be restricted – you'd have to use Flash or a Java applet or something like that to handle the file transfer.

And of course it goes without saying that this doesn't do anything to verify the validity of the file type. You'll do that on the server-side once the file has uploaded.

A little update – with javascript and the FileReader API you could do more validation client-side before uploading huge files to your server and checking them again.

Return value from a VBScript function

To return a value from a VBScript function, assign the value to the name of the function, like this:

Function getNumber
    getNumber = "423"
End Function

Using Ajax.BeginForm with ASP.NET MVC 3 Razor

I think that all the answers missed a crucial point:

If you use the Ajax form so that it needs to update itself (and NOT another div outside of the form) then you need to put the containing div OUTSIDE of the form. For example:

 <div id="target">
 @using (Ajax.BeginForm("MyAction", "MyController",
            new AjaxOptions
            {
                HttpMethod = "POST",
                InsertionMode = InsertionMode.Replace,
                UpdateTargetId = "target"
            }))
 {
      <!-- whatever -->
 }
 </div>

Otherwise you will end like @David where the result is displayed in a new page.

How to access local files of the filesystem in the Android emulator?

In Android Studio 3.0 and later do this:

View > Tool Windows > Device File Explorer

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

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

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

Whats the CSS to make something go to the next line in the page?

Have the element display as a block:

display: block;

Volley - POST/GET parameters

CustomRequest is a way to solve the Volley's JSONObjectRequest can't post parameters like the StringRequest

here is the helper class which allow to add params:

    import java.io.UnsupportedEncodingException;
    import java.util.Map;    
    import org.json.JSONException;
    import org.json.JSONObject;    
    import com.android.volley.NetworkResponse;
    import com.android.volley.ParseError;
    import com.android.volley.Request;
    import com.android.volley.Response;
    import com.android.volley.Response.ErrorListener;
    import com.android.volley.Response.Listener;
    import com.android.volley.toolbox.HttpHeaderParser;

    public class CustomRequest extends Request<JSONObject> {

    private Listener<JSONObject> listener;
    private Map<String, String> params;

    public CustomRequest(String url, Map<String, String> params,
            Listener<JSONObject> reponseListener, ErrorListener errorListener) {
        super(Method.GET, url, errorListener);
        this.listener = reponseListener;
        this.params = params;
    }

    public CustomRequest(int method, String url, Map<String, String> params,
            Listener<JSONObject> reponseListener, ErrorListener errorListener) {
        super(method, url, errorListener);
        this.listener = reponseListener;
        this.params = params;
    }

    protected Map<String, String> getParams()
            throws com.android.volley.AuthFailureError {
        return params;
    };

    @Override
    protected Response<JSONObject> parseNetworkResponse(NetworkResponse response) {
        try {
            String jsonString = new String(response.data,
                    HttpHeaderParser.parseCharset(response.headers));
            return Response.success(new JSONObject(jsonString),
                    HttpHeaderParser.parseCacheHeaders(response));
        } catch (UnsupportedEncodingException e) {
            return Response.error(new ParseError(e));
        } catch (JSONException je) {
            return Response.error(new ParseError(je));
        }
    }

    @Override
    protected void deliverResponse(JSONObject response) {
        // TODO Auto-generated method stub
        listener.onResponse(response);
    }

}

thanks to Greenchiu

Django Reverse with arguments '()' and keyword arguments '{}' not found

The solution @miki725 is absolutely correct. Alternatively, if you would like to use the args attribute as opposed to kwargs, then you can simply modify your code as follows:

project_id = 4
reverse('edit_project', args=(project_id,))

An example of this can be found in the documentation. This essentially does the same thing, but the attributes are passed as arguments. Remember that any arguments that are passed need to be assigned a value before being reversed. Just use the correct namespace, which in this case is 'edit_project'.

PHP filesize MB/KB conversion

A complete example.

<?php
    $units = explode(' ','B KB MB GB TB PB');
    echo("<html><body>");
    echo('file size: ' . format_size(filesize("example.txt")));
    echo("</body></html>");


    function format_size($size) {

        $mod = 1024;

        for ($i = 0; $size > $mod; $i++) {
            $size /= $mod;
        }

        $endIndex = strpos($size, ".")+3;

        return substr( $size, 0, $endIndex).' '.$units[$i];
    }
?>

What does the Ellipsis object do?

Summing up what others have said, as of Python 3, Ellipsis is essentially another singleton constant similar to None, but without a particular intended use. Existing uses include:

  • In slice syntax to represent the full slice in remaining dimensions
  • In type hinting to indicate only part of a type(Callable[..., int] or Tuple[str, ...])
  • In type stub files to indicate there is a default value without specifying it

Possible uses could include:

  • As a default value for places where None is a valid option
  • As the content for a function you haven't implemented yet

How to set environment variables from within package.json?

Set the environment variable in the script command:

...
"scripts": {
  "start": "node app.js",
  "test": "NODE_ENV=test mocha --reporter spec"
},
...

Then use process.env.NODE_ENV in your app.

Note: This is for Mac & Linux only. For Windows refer to the comments.

How to add browse file button to Windows Form using C#

These links explain it with examples

http://dotnetperls.com/openfiledialog

http://www.geekpedia.com/tutorial67_Using-OpenFileDialog-to-open-files.html

private void button1_Click(object sender, EventArgs e)
{
    int size = -1;
    DialogResult result = openFileDialog1.ShowDialog(); // Show the dialog.
    if (result == DialogResult.OK) // Test result.
    {
       string file = openFileDialog1.FileName;
       try
       {
          string text = File.ReadAllText(file);
          size = text.Length;
       }
       catch (IOException)
       {
       }
    }
    Console.WriteLine(size); // <-- Shows file size in debugging mode.
    Console.WriteLine(result); // <-- For debugging use.
}

SQL to add column and comment in table in single command

Add comments for two different columns of the EMPLOYEE table :

COMMENT ON EMPLOYEE
     (WORKDEPT IS 'see DEPARTMENT table for names',
     EDLEVEL IS 'highest grade level passed in school' )

What is the default initialization of an array in Java?

Java says that the default length of a JAVA array at the time of initialization will be 10.

private static final int DEFAULT_CAPACITY = 10;

But the size() method returns the number of inserted elements in the array, and since at the time of initialization, if you have not inserted any element in the array, it will return zero.

private int size;

public boolean add(E e) {
    ensureCapacityInternal(size + 1);  // Increments modCount!!
    elementData[size++] = e;
    return true;
}

public void add(int index, E element) {
    rangeCheckForAdd(index);
    ensureCapacityInternal(size + 1);  // Increments modCount!!
    System.arraycopy(elementData, index, elementData, index + 1,size - index);
    elementData[index] = element;
    size++;
}

How to fill background image of an UIView

For Swift use this...

UIGraphicsBeginImageContext(self.view.frame.size)
UIImage(named: "ImageName.png")?.draw(in: self.view.bounds)

if let image = UIGraphicsGetImageFromCurrentImageContext(){
    UIGraphicsEndImageContext()
    self.view.backgroundColor = UIColor(patternImage: image)
}else{
    UIGraphicsEndImageContext()
    debugPrint("Image not available")
 }

How to achieve ripple animation using support library?

Basic ripple setup

  • Ripples contained within the view.
    android:background="?selectableItemBackground"

  • Ripples that extend beyond the view's bounds:
    android:background="?selectableItemBackgroundBorderless"

    Have a look here for resolving ?(attr) xml references in Java code.

Support Library

  • Using ?attr: (or the ? shorthand) instead of ?android:attr references the support library, so is available back to API 7.

Ripples with images/backgrounds

  • To have a image or background and overlaying ripple the easiest solution is to wrap the View in a FrameLayout with the ripple set with setForeground() or setBackground().

Honestly there is no clean way of doing this otherwise.

How to run Visual Studio post-build events for debug build only

You can pass the configuration name to the post-build script and check it in there to see if it should run.

Pass the configuration name with $(ConfigurationName).

Checking it is based on how you are implementing the post-build step -- it will be a command-line argument.

Copy multiple files with Ansible

 
- hosts: lnx
  tasks:
    - find: paths="/appl/scripts/inq" recurse=yes patterns="inq.Linux*"
      register: file_to_copy
    - copy: src={{ item.path }} dest=/usr/local/sbin/
      owner: root
      mode: 0775
      with_items: "{{ files_to_copy.files }}"

Hashing a string with Sha256

In the PHP version you can send 'true' in the last parameter, but the default is 'false'. The following algorithm is equivalent to the default PHP's hash function when passing 'sha256' as the first parameter:

public static string GetSha256FromString(string strData)
    {
        var message = Encoding.ASCII.GetBytes(strData);
        SHA256Managed hashString = new SHA256Managed();
        string hex = "";

        var hashValue = hashString.ComputeHash(message);
        foreach (byte x in hashValue)
        {
            hex += String.Format("{0:x2}", x);
        }
        return hex;
    }

Select first row in each GROUP BY group?

The Query:

SELECT purchases.*
FROM purchases
LEFT JOIN purchases as p 
ON 
  p.customer = purchases.customer 
  AND 
  purchases.total < p.total
WHERE p.total IS NULL

HOW DOES THAT WORK! (I've been there)

We want to make sure that we only have the highest total for each purchase.

Some Theoretical Stuff (skip this part if you only want to understand the query)

Let Total be a function T(customer,id) where it returns a value given the name and id To prove that the given total (T(customer,id)) is the highest we have to prove that We want to prove either

  • ?x T(customer,id) > T(customer,x) (this total is higher than all other total for that customer)

OR

  • ¬?x T(customer, id) < T(customer, x) (there exists no higher total for that customer)

The first approach will need us to get all the records for that name which I do not really like.

The second one will need a smart way to say there can be no record higher than this one.

Back to SQL

If we left joins the table on the name and total being less than the joined table:

LEFT JOIN purchases as p 
ON 
p.customer = purchases.customer 
AND 
purchases.total < p.total

we make sure that all records that have another record with the higher total for the same user to be joined:

+--------------+---------------------+-----------------+------+------------+---------+
| purchases.id |  purchases.customer | purchases.total | p.id | p.customer | p.total |
+--------------+---------------------+-----------------+------+------------+---------+
|            1 | Tom                 |             200 |    2 | Tom        |     300 |
|            2 | Tom                 |             300 |      |            |         |
|            3 | Bob                 |             400 |    4 | Bob        |     500 |
|            4 | Bob                 |             500 |      |            |         |
|            5 | Alice               |             600 |    6 | Alice      |     700 |
|            6 | Alice               |             700 |      |            |         |
+--------------+---------------------+-----------------+------+------------+---------+

That will help us filter for the highest total for each purchase with no grouping needed:

WHERE p.total IS NULL
    
+--------------+----------------+-----------------+------+--------+---------+
| purchases.id | purchases.name | purchases.total | p.id | p.name | p.total |
+--------------+----------------+-----------------+------+--------+---------+
|            2 | Tom            |             300 |      |        |         |
|            4 | Bob            |             500 |      |        |         |
|            6 | Alice          |             700 |      |        |         |
+--------------+----------------+-----------------+------+--------+---------+

And that's the answer we need.

How to merge specific files from Git branches

You can stash and stash pop the file:

git checkout branch1
git checkout branch2 file.py
git stash
git checkout branch1
git stash pop

What is the optimal way to compare dates in Microsoft SQL server?

Converting to a DATE or using an open-ended date range in any case will yield the best performance. FYI, convert to date using an index are the best performers. More testing a different techniques in article: What is the most efficient way to trim time from datetime? Posted by Aaron Bertrand

From that article:

DECLARE @dateVar datetime = '19700204';

-- Quickest when there is an index on t.[DateColumn], 
-- because CONVERT can still use the index.
SELECT t.[DateColumn]
FROM MyTable t
WHERE = CONVERT(DATE, t.[DateColumn]) = CONVERT(DATE, @dateVar);

-- Quicker when there is no index on t.[DateColumn]
DECLARE @dateEnd datetime = DATEADD(DAY, 1, @dateVar);
SELECT t.[DateColumn] 
FROM MyTable t
WHERE t.[DateColumn] >= @dateVar AND 
      t.[DateColumn] < @dateEnd;

Also from that article: using BETWEEN, DATEDIFF or CONVERT(CHAR(8)... are all slower.

javascript popup alert on link click

Single line works just fine:

<a href="http://example.com/"
 onclick="return confirm('Please click on OK to continue.');">click me</a>

Adding another line with a different link on the same page works fine too:

<a href="http://stackoverflow.com/"
 onclick="return confirm('Click on another OK to continue.');">another link</a>

How can I set an SQL Server connection string?

.NET DataProvider -- Standard Connection with username and password

using System.Data.SqlClient;

SqlConnection conn = new SqlConnection();
conn.ConnectionString =
  "Data Source=ServerName;" +
  "Initial Catalog=DataBaseName;" +
  "User id=UserName;" +
  "Password=Secret;";
conn.Open();

.NET DataProvider -- Trusted Connection

SqlConnection conn = new SqlConnection();
conn.ConnectionString =
  "Data Source=ServerName;" +
  "Initial Catalog=DataBaseName;" +
  "Integrated Security=SSPI;";
conn.Open();

Refer to the documentation.

gitignore all files of extension in directory

I have tried opening the .gitignore file in my vscode, windows 10. There you can see, some previously added ignore files (if any).

To create a new rule to ignore a file with (.js) extension, append the extension of the file like this:

*.js

This will ignore all .js files in your git repository.

To exclude certain type of file from a particular directory, you can add this:

**/foo/*.js

This will ignore all .js files inside only /foo/ directory.

For a detailed learning you can visit: about git-ignore

Java8: sum values from specific field of the objects in a list

You can also collect with an appropriate summing collector like Collectors#summingInt(ToIntFunction)

Returns a Collector that produces the sum of a integer-valued function applied to the input elements. If no elements are present, the result is 0.

For example

Stream<Obj> filtered = list.stream().filter(o -> o.field > 10);
int sum = filtered.collect(Collectors.summingInt(o -> o.field));

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

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

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

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

Uninstall Django completely

The Issue is with pip --version or python --version.

try solving issue with pip2.7 uninstall Django command

If you are not able to uninstall using the above command then for sure your pip2.7 version is not installed so you can follow the below steps:

1)which pip2.7 it should give you an output like this :

/usr/local/bin/pip2.7

2) If you have not got this output please install pip using following commands

$ wget https://bootstrap.pypa.io/get-pip.py
$ sudo python2.7 get-pip.py

3) Now check your pip version : which pip2.7 Now you will get 

/usr/local/bin/pip2.7 as output

4) uninstall Django using pip2.7 uninstall Django command.

Problem can also be related to Python version. I had a similar problem, this is how I uninstalled Django.

Issue occurred because I had multiple python installed in my virtual environment.

$ ls

activate       activate_this.py  easy_install-3.4  pip2.7  python     python3        wheel
activate.csh   easy_install      pip               pip3    python2    python3.4
activate.fish  easy_install-2.7  pip2              pip3.4  python2.7  python-config

Now when I tried to un-install using pip uninstall Django Django got uninstalled from python 2.7 but not from python 3.4 so I followed the following steps to resolve the issue :

1)alias python=/usr/bin/python3

2) Now check your python version using python -V command

3) If you have switched to your required python version now you can simply uninstall Django using pip3 uninstall Django command

Hope this answer helps.

jQuery click event not working after adding class

You should use the following:

$('#gentab').on('click', 'a.tabclick', function(event) {
    event.preventDefault();
    var liId = $(this).closest("li").attr("id");
    alert(liId);  
});

This will attach your event to any anchors within the #gentab element, reducing the scope of having to check the whole document element tree and increasing efficiency.

I want to vertical-align text in select box

I used to use height and line-height with the same values, but the proved to be inconsistent across the interwebs. My current approach is to mix that with padding like so.

select {
  font-size:14px;
  height:18px;
  line-height:18px;
  padding:5px 0;
  width:200px;
  text-align:center;
}

You could also use padding for the horizontal value instead of the width + text-align