Programs & Examples On #Pre commit

Pre-commit is an action taken prior to committing your code into a version control system.

SVN Error: Commit blocked by pre-commit hook (exit code 1) with output: Error: n/a (6)

A pre-commit hook is something that runs on the server, so this probably has nothing to do with your local setup. It could be that you changed something in a settings panel on myversioncontrol.com that is implemented using a pre-commit hook or the myversioncontrol people made an error and added a non-functioning hook.

HttpListener Access Denied

If you use http://localhost:80/ as a prefix, you can listen to http requests with no need for Administrative privileges.

Is there a decent wait function in C++?

Before the return statement in you main, insert this code:

system("pause");

This will hold the console until you hit a key.

#include<iostream>
#include<string>

using namespace std;

int main()
{
    string s;
    cout << "Please enter your first name followed by a newline\n";
    cin >> s;
    cout << "Hello, " << s << '\n';
    system("pause");
    return 0; // this return statement isn't necessary
}

Angular window resize event

Below code lets observe any size change for any given div in Angular.

<div #observed-div>
</div>

then in the Component:

oldWidth = 0;
oldHeight = 0;

@ViewChild('observed-div') myDiv: ElementRef;
ngAfterViewChecked() {
  const newWidth = this.myDiv.nativeElement.offsetWidth;
  const newHeight = this.myDiv.nativeElement.offsetHeight;
  if (this.oldWidth !== newWidth || this.oldHeight !== newHeight)
    console.log('resized!');

  this.oldWidth = newWidth;
  this.oldHeight = newHeight;
}

Code for printf function in C

Here's the GNU version of printf... you can see it passing in stdout to vfprintf:

__printf (const char *format, ...)
{
   va_list arg;
   int done;

   va_start (arg, format);
   done = vfprintf (stdout, format, arg);
   va_end (arg);

   return done;
}

See here.

Here's a link to vfprintf... all the formatting 'magic' happens here.

The only thing that's truly 'different' about these functions is that they use varargs to get at arguments in a variable length argument list. Other than that, they're just traditional C. (This is in contrast to Pascal's printf equivalent, which is implemented with specific support in the compiler... at least it was back in the day.)

How to retrieve form values from HTTPPOST, dictionary or?

If you want to get the form data directly from Http request, without any model bindings or FormCollection you can use this:

[HttpPost] 
public ActionResult SubmitAction() {

    // This will return an string array of all keys in the form.
    // NOTE: you specify the keys in form by the name attributes e.g:
    // <input name="this is the key" value="some value" type="test" />
    var keys = Request.Form.AllKeys;

    // This will return the value for the keys.
    var value1 = Request.Form.Get(keys[0]);
    var value2 = Request.Form.Get(keys[1]);
}

iOS - UIImageView - how to handle UIImage image orientation

Inspired from @Aqua Answer.....

in Objective C

- (UIImage *)fixImageOrientation:(UIImage *)img {

   UIGraphicsBeginImageContext(img.size);
   [img drawAtPoint:CGPointZero];

   UIImage *newImg = UIGraphicsGetImageFromCurrentImageContext();
   UIGraphicsEndImageContext();

   if (newImg) {
       return newImg;
   }

   return img;
}

React-router: How to manually invoke Link?

React Router v5 - React 16.8+ with Hooks (updated 09/23/2020)

If you're leveraging React Hooks, you can take advantage of the useHistory API that comes from React Router v5.

import React, {useCallback} from 'react';
import {useHistory} from 'react-router-dom';

export default function StackOverflowExample() {
  const history = useHistory();
  const handleOnClick = useCallback(() => history.push('/sample'), [history]);

  return (
    <button type="button" onClick={handleOnClick}>
      Go home
    </button>
  );
}

Another way to write the click handler if you don't want to use useCallback

const handleOnClick = () => history.push('/sample');

React Router v4 - Redirect Component

The v4 recommended way is to allow your render method to catch a redirect. Use state or props to determine if the redirect component needs to be shown (which then trigger's a redirect).

import { Redirect } from 'react-router';

// ... your class implementation

handleOnClick = () => {
  // some action...
  // then redirect
  this.setState({redirect: true});
}

render() {
  if (this.state.redirect) {
    return <Redirect push to="/sample" />;
  }

  return <button onClick={this.handleOnClick} type="button">Button</button>;
}

Reference: https://reacttraining.com/react-router/web/api/Redirect

React Router v4 - Reference Router Context

You can also take advantage of Router's context that's exposed to the React component.

static contextTypes = {
  router: PropTypes.shape({
    history: PropTypes.shape({
      push: PropTypes.func.isRequired,
      replace: PropTypes.func.isRequired
    }).isRequired,
    staticContext: PropTypes.object
  }).isRequired
};

handleOnClick = () => {
  this.context.router.push('/sample');
}

This is how <Redirect /> works under the hood.

Reference: https://github.com/ReactTraining/react-router/blob/master/packages/react-router/modules/Redirect.js#L46,L60

React Router v4 - Externally Mutate History Object

If you still need to do something similar to v2's implementation, you can create a copy of BrowserRouter then expose the history as an exportable constant. Below is a basic example but you can compose it to inject it with customizable props if needed. There are noted caveats with lifecycles, but it should always rerender the Router, just like in v2. This can be useful for redirects after an API request from an action function.

// browser router file...
import createHistory from 'history/createBrowserHistory';
import { Router } from 'react-router';

export const history = createHistory();

export default class BrowserRouter extends Component {
  render() {
    return <Router history={history} children={this.props.children} />
  }
}

// your main file...
import BrowserRouter from './relative/path/to/BrowserRouter';
import { render } from 'react-dom';

render(
  <BrowserRouter>
    <App/>
  </BrowserRouter>
);

// some file... where you don't have React instance references
import { history } from './relative/path/to/BrowserRouter';

history.push('/sample');

Latest BrowserRouter to extend: https://github.com/ReactTraining/react-router/blob/master/packages/react-router-dom/modules/BrowserRouter.js

React Router v2

Push a new state to the browserHistory instance:

import {browserHistory} from 'react-router';
// ...
browserHistory.push('/sample');

Reference: https://github.com/reactjs/react-router/blob/master/docs/guides/NavigatingOutsideOfComponents.md

Changing default shell in Linux

You should have a 'skeleton' somewhere in /etc, probably /etc/skeleton, or check the default settings, probably /etc/default or something. Those are scripts that define standard environment variables getting set during a login.

If it is just for your own account: check the (hidden) file ~/.profile and ~/.login. Or generate them, if they don't exist. These are also evaluated by the login process.

How to use java.Set

Did you override equals and hashCode in the Block class?

EDIT:

I assumed you mean it doesn't work at runtime... did you mean that or at compile time? If compile time what is the error message? If it crashes at runtime what is the stack trace? If it compiles and runs but doesn't work right then the equals and hashCode are the likely issue.

How do I get an object's unqualified (short) class name?

You can do this with reflection. Specifically, you can use the ReflectionClass::getShortName method, which gets the name of the class without its namespace.

First, you need to build a ReflectionClass instance, and then call the getShortName method of that instance:

$reflect = new ReflectionClass($object);
if ($reflect->getShortName() === 'Name') {
    // do this
}

However, I can't imagine many circumstances where this would be desirable. If you want to require that the object is a member of a certain class, the way to test it is with instanceof. If you want a more flexible way to signal certain constraints, the way to do that is to write an interface and require that the code implement that interface. Again, the correct way to do this is with instanceof. (You can do it with ReflectionClass, but it would have much worse performance.)

Function return value in PowerShell

It's hard to say without looking at at code. Make sure your function doesn't return more than one object and that you capture any results made from other calls. What do you get for:

@($returnURL).count

Anyway, two suggestions:

Cast the object to string:

...
return [string]$rs

Or just enclose it in double quotes, same as above but shorter to type:

...
return "$rs"

Combine or merge JSON on node.js without jQuery

Let object1 and object2 be two JSON object.

var object1 = [{"name": "John"}];
var object2 = [{"location": "San Jose"}];

object1.push(object2);

This will simply append object2 in object1:

[{"name":"John"},{"location":"San Jose"}]

Refresh Page and Keep Scroll Position

This might be useful for refreshing also. But if you want to keep track of position on the page before you click on a same position.. The following code will help.

Also added a data-confirm for prompting the user if they really want to do that..

Note: I'm using jQuery and js-cookie.js to store cookie info.

$(document).ready(function() {
    // make all links with data-confirm prompt the user first.
    $('[data-confirm]').on("click", function (e) {
        e.preventDefault();
        var msg = $(this).data("confirm");
        if(confirm(msg)==true) {
            var url = this.href;
            if(url.length>0) window.location = url;
            return true;
        }
        return false;
    });

    // on certain links save the scroll postion.
    $('.saveScrollPostion').on("click", function (e) {
        e.preventDefault();
        var currentYOffset = window.pageYOffset;  // save current page postion.
        Cookies.set('jumpToScrollPostion', currentYOffset);
        if(!$(this).attr("data-confirm")) {  // if there is no data-confirm on this link then trigger the click. else we have issues.
            var url = this.href;
            window.location = url;
            //$(this).trigger('click');  // continue with click event.
        }
    });

    // check if we should jump to postion.
    if(Cookies.get('jumpToScrollPostion') !== "undefined") {
        var jumpTo = Cookies.get('jumpToScrollPostion');
        window.scrollTo(0, jumpTo);
        Cookies.remove('jumpToScrollPostion');  // and delete cookie so we don't jump again.
    }
});

A example of using it like this.

<a href='gotopage.html' class='saveScrollPostion' data-confirm='Are you sure?'>Goto what the heck</a>

Adding an external directory to Tomcat classpath

I might be a bit late for the party but I follow below steps to make it fully configurable using IntelliJ's way of in-IDE app test. I believe the best way to go with is to Combine below with @BelusC's answer.

1. run the application using IDE's tomcat run config. 
2. ps -ef | grep -i tomcat //this will give you a good idea about what the ide doing actually.
3. Copy the -Dcatalina.base parameter value from the command. this is your application specific catalina base. In this folder you can play with catalina.properties, application root path etc.. basically everything you have been doing is doable here too. 

Python: Total sum of a list of numbers with the for loop

x=[1,2,3,4,5]
sum=0
for s in range(0,len(x)):
   sum=sum+x[s]
print sum   

Javascript communication between browser tabs/windows

You can do this via local storage API. Note that this works only between 2 tabs. you can't put both sender and receiver on the same page:

On sender page:

localStorage.setItem("someKey", "someValue");

On the receiver page

    $(document).ready(function () {

        window.addEventListener('storage', storageEventHandler, false);

        function storageEventHandler(evt) {
            alert("storage event called key: " + evt.key);
        }
    });

Not able to pip install pickle in python 3.6

import pickle

intArray = [i for i in range(1,100)]
output = open('data.pkl', 'wb')
pickle.dump(intArray, output)
output.close()

Test your pickle quickly. pickle is a part of standard python library and available by default.

Iterating through populated rows

I'm going to make a couple of assumptions in my answer. I'm assuming your data starts in A1 and there are no empty cells in the first column of each row that has data.

This code will:

  1. Find the last row in column A that has data
  2. Loop through each row
  3. Find the last column in current row with data
  4. Loop through each cell in current row up to last column found.

This is not a fast method but will iterate through each one individually as you suggested is your intention.


Sub iterateThroughAll()
    ScreenUpdating = False
    Dim wks As Worksheet
    Set wks = ActiveSheet

    Dim rowRange As Range
    Dim colRange As Range

    Dim LastCol As Long
    Dim LastRow As Long
    LastRow = wks.Cells(wks.Rows.Count, "A").End(xlUp).Row

    Set rowRange = wks.Range("A1:A" & LastRow)

    'Loop through each row
    For Each rrow In rowRange
        'Find Last column in current row
        LastCol = wks.Cells(rrow, wks.Columns.Count).End(xlToLeft).Column
        Set colRange = wks.Range(wks.Cells(rrow, 1), wks.Cells(rrow, LastCol))

        'Loop through all cells in row up to last col
        For Each cell In colRange
            'Do something to each cell
            Debug.Print (cell.Value)
        Next cell
    Next rrow
    ScreenUpdating = True
End Sub

How to convert a column of DataTable to a List

1.Very Simple Code to iterate datatable and get columns in list.

2.code ==>>>

 foreach (DataColumn dataColumn in dataTable.Columns)
 {
    var list = dataTable.Rows.OfType<DataRow>()
     .Select(dataRow => dataRow.Field<string> 
       (dataColumn.ToString())).ToList();
 }

How to get the scroll bar with CSS overflow on iOS

I have done some testing and using CSS3 to redefine the scrollbars works and you get to keep your Overflow:scroll; or Overflow:auto

I ended up with something like this...

::-webkit-scrollbar {
    width: 15px;
    height: 15px;
    border-bottom: 1px solid #eee; 
    border-top: 1px solid #eee;
}
::-webkit-scrollbar-thumb {
    border-radius: 8px;
    background-color: #C3C3C3;
    border: 2px solid #eee;
}

::-webkit-scrollbar-track {
    -webkit-box-shadow: inset 0 0 6px rgba(0,0,0,0.2); 
} 

The only down side which I have not yet been able to figure out is how to interact with the scrollbars on iProducts but you can interact with the content to scroll it

How to check if an integer is in a given range?

if(i <= 0 || i >=100)

It will work.

Consistency of hashCode() on a Java string

As said above, in general you should not rely on the hash code of a class remaining the same. Note that even subsequent runs of the same application on the same VM may produce different hash values. AFAIK the Sun JVM's hash function calculates the same hash on every run, but that's not guaranteed.

Note that this is not theoretical. The hash function for java.lang.String was changed in JDK1.2 (the old hash had problems with hierarchical strings like URLs or file names, as it tended to produce the same hash for strings which only differed at the end).

java.lang.String is a special case, as the algorithm of its hashCode() is (now) documented, so you can probably rely on that. I'd still consider it bad practice. If you need a hash algorithm with special, documented properties, just write one :-).

How do I measure a time interval in C?

Using the time.h library, try something like this:

long start_time, end_time, elapsed;

start_time = clock();
// Do something
end_time = clock();

elapsed = (end_time - start_time) / CLOCKS_PER_SEC * 1000;

Can I grep only the first n lines of a file?

An extension to Joachim Isaksson's answer: Quite often I need something from the middle of a long file, e.g. lines 5001 to 5020, in which case you can combine head with tail:

head -5020 file.txt | tail -20 | grep x

This gets the first 5020 lines, then shows only the last 20 of those, then pipes everything to grep.

(Edited: fencepost error in my example numbers, added pipe to grep)

Python pip install module is not found. How to link python to pip location?

If your python and pip binaries are from different versions, modules installed using pip will not be available to python.

Steps to resolve:

  1. Open up a fresh terminal with a default environment and locate the binaries for pip and python.
readlink $(which pip)
../Cellar/python@2/2.7.15_1/bin/pip

readlink $(which python)
/usr/local/bin/python3      <-- another symlink

readlink /usr/local/bin/python3
../Cellar/python/3.7.2/bin/python3

Here you can see an obvious mismatch between the versions 2.7.15_1 and 3.7.2 in my case.

  1. Replace the pip symlink with the pip binary which matches your current version of python. Use your python version in the following command.
ln -is /usr/local/Cellar/python/3.7.2/bin/pip3 $(which pip)

The -i flag promts you to overwrite if the target exists.

That should do the trick.

Initializing data.frames()

I always just convert a matrix:

x <- as.data.frame(matrix(nrow = 100, ncol = 10))

How to compare two dates in Objective-C

By this method also you can compare two dates

NSDate * dateOne = [NSDate date];
NSDate * dateTwo = [NSDate date];

if([dateOne compare:dateTwo] == NSOrderedAscending)
{

}

Label python data points on plot

How about print (x, y) at once.

from matplotlib import pyplot as plt

fig = plt.figure()
ax = fig.add_subplot(111)

A = -0.75, -0.25, 0, 0.25, 0.5, 0.75, 1.0
B = 0.73, 0.97, 1.0, 0.97, 0.88, 0.73, 0.54

plt.plot(A,B)
for xy in zip(A, B):                                       # <--
    ax.annotate('(%s, %s)' % xy, xy=xy, textcoords='data') # <--

plt.grid()
plt.show()

enter image description here

Why is my power operator (^) not working?

First of all ^ is a Bitwise XOR operator not power operator.

You can use other things to find power of any number. You can use for loop to find power of any number

Here is a program to find x^y i.e. xy

double i, x, y, pow;

x = 2;
y = 5; 
pow = 1;
for(i=1; i<=y; i++)
{
    pow = pow * x;
}

printf("2^5 = %lf", pow);

You can also simply use pow() function to find power of any number

double power, x, y;
x = 2;
y = 5;
power = pow(x, y); /* include math.h header file */

printf("2^5 = %lf", power);

Convert XmlDocument to String

" is shown as \" in the debugger, but the data is correct in the string, and you don't need to replace anything. Try to dump your string to a file and you will note that the string is correct.

subquery in codeigniter active record

    $where.= '(';
    $where.= 'admin_trek.trek='."%$search%".'  AND ';
    $where.= 'admin_trek.state_id='."$search".'  OR ';
    $where.= 'admin_trek.difficulty='."$search".' OR ';
    $where.= 'admin_trek.month='."$search".'  AND ';
    $where.= 'admin_trek.status = 1)';

    $this->db->select('*');
    $this->db->from('admin_trek');
    $this->db->join('admin_difficulty',admin_difficulty.difficulty_id = admin_trek.difficulty');
    $this->db->where($where); 
    $query = $this->db->get();

Eloquent Collection: Counting and Detect Empty

According to Laravel Documentation states you can use this way:

$result->isEmpty();

The isEmpty method returns true if the collection is empty; otherwise, false is returned.

How to justify a single flexbox item (override justify-content)

If you aren't actually restricted to keeping all of these elements as sibling nodes you can wrap the ones that go together in another default flex box, and have the container of both use space-between.

_x000D_
_x000D_
.space-between {_x000D_
  border: 1px solid red;_x000D_
  display: flex;_x000D_
  justify-content: space-between;_x000D_
}_x000D_
.default-flex {_x000D_
  border: 1px solid blue;_x000D_
  display: flex;_x000D_
}_x000D_
.child {_x000D_
  width: 100px;_x000D_
  height: 100px;_x000D_
  border: 1px solid;_x000D_
}
_x000D_
<div class="space-between">_x000D_
  <div class="child">1</div>_x000D_
  <div class="default-flex">_x000D_
    <div class="child">2</div>_x000D_
    <div class="child">3</div>_x000D_
    <div class="child">4</div>_x000D_
    <div class="child">5</div>_x000D_
  </div>_x000D_
</div>
_x000D_
_x000D_
_x000D_

Or if you were doing the same thing with flex-start and flex-end reversed you just swap the order of the default-flex container and lone child.

How to run a javascript function during a mouseover on a div

Using the title attribute:

<div id="sub1 sub2 sub3" title="some text on mouse over">some text</div>

Apply CSS to jQuery Dialog Buttons

There is also a simple answer for defining specific styles that are only going to be applied to that specific button and you can have Jquery declare element style when declaring the dialog:

id: "button-delete",
text: "Delete",
style: "display: none;",
click: function () {}

after doing that here is what the html shows: enter image description here

doing this allows you to set it, but it is not necessarily easy to change using jquery later.

TypeError: worker() takes 0 positional arguments but 1 was given

another use case for this error is when you import functions within the class definition. this makes the subsequent function calls a part of the class object. In this case you can use @staticmethod on the library import function or make a static path call directly to the function. see example below

In this example "self.bar()" will throw a TypeError, but it can be fixed in two ways

# in lib.py
def bar():
  print('something to do')

# in foo.py
class foo():
  from .lib import bar

  def __init__(self):
    self.bar()

Option 1:

# in lib.py
def bar():
  print('something to do')

# in foo.py
class foo():
  from .lib import bar

  def __init__(self):
    lib.bar()

Option 2:

# in lib.py:
@staticmethod
def bar():
  print('something to do')

# in foo.py
class foo():
  from .lib import bar

  def __init__(self):
    self.bar()

Checking character length in ruby

Instead of using a regular expression, just check if string.length > 25

In WPF, what are the differences between the x:Name and Name attributes?

The specified x:Name becomes the name of a field that is created in the underlying code when XAML is processed, and that field holds a reference to the object. In Silverlight, using the managed API, the process of creating this field is performed by the MSBuild target steps, which also are responsible for joining the partial classes for a XAML file and its code-behind. This behavior is not necessarily XAML-language specified; it is the particular implementation that Silverlight applies to use x:Name in its programming and application models.

Read More on MSDN...

how to add css class to html generic control div?

To add a class to a div that is generated via the HtmlGenericControl way you can use:

div1.Attributes.Add("class", "classname"); 

If you are using the Panel option, it would be:

panel1.CssClass = "classname";

How to fix div on scroll

(function($) {
  var triggers = [];
  $.fn.floatingFixed = function(options) {
    options = $.extend({}, $.floatingFixed.defaults, options);
    var r = $(this).each(function() {
      var $this = $(this), pos = $this.position();
      pos.position = $this.css("position");
      $this.data("floatingFixedOrig", pos);
      $this.data("floatingFixedOptions", options);
      triggers.push($this);
    });
    windowScroll();
    return r;
  };

  $.floatingFixed = $.fn.floatingFixed;
  $.floatingFixed.defaults = {
    padding: 0
  };

  var $window = $(window);
  var windowScroll = function() {
    if(triggers.length === 0) { return; }
    var scrollY = $window.scrollTop();
    for(var i = 0; i < triggers.length; i++) {
      var t = triggers[i], opt = t.data("floatingFixedOptions");
      if(!t.data("isFloating")) {
        var off = t.offset();
        t.data("floatingFixedTop", off.top);
        t.data("floatingFixedLeft", off.left);
      }
      var top = top = t.data("floatingFixedTop");
      if(top < scrollY + opt.padding && !t.data("isFloating")) {
        t.css({position: 'fixed', top: opt.padding, left: t.data("floatingFixedLeft"), width: t.width() }).data("isFloating", true);
      } else if(top >= scrollY + opt.padding && t.data("isFloating")) {
        var pos = t.data("floatingFixedOrig");
        t.css(pos).data("isFloating", false);
      }
    }
  };

  $window.scroll(windowScroll).resize(windowScroll);
})(jQuery);

and then make any div as floating fixed by calling

$('#id of the div').floatingFixed();

source: https://github.com/cheald/floatingFixed

How to get the mysql table columns data type?

Please use the below mysql query.

SELECT COLUMN_NAME, DATA_TYPE, CHARACTER_MAXIMUM_LENGTH 
FROM information_schema.columns 
WHERE table_schema = '<DATABASE NAME>' 
AND table_name = '<TABLE NAME>' 
AND COLUMN_NAME = '<COLOMN NAME>' 

MySql Query Result

Getting path of captured image in Android using camera intent

Try like this

Pass Camera Intent like below

Intent intent = new Intent(this);
startActivityForResult(intent, REQ_CAMERA_IMAGE);

And after capturing image Write an OnActivityResult as below

protected void onActivityResult(int requestCode, int resultCode, Intent data) {  
    if (requestCode == CAMERA_REQUEST && resultCode == RESULT_OK) {
        Bitmap photo = (Bitmap) data.getExtras().get("data"); 
        imageView.setImageBitmap(photo);
        knop.setVisibility(Button.VISIBLE);


        // CALL THIS METHOD TO GET THE URI FROM THE BITMAP
        Uri tempUri = getImageUri(getApplicationContext(), photo);

        // CALL THIS METHOD TO GET THE ACTUAL PATH
        File finalFile = new File(getRealPathFromURI(tempUri));

        System.out.println(mImageCaptureUri);
    }  
}

public Uri getImageUri(Context inContext, Bitmap inImage) {
    ByteArrayOutputStream bytes = new ByteArrayOutputStream();
    inImage.compress(Bitmap.CompressFormat.JPEG, 100, bytes);
    String path = Images.Media.insertImage(inContext.getContentResolver(), inImage, "Title", null);
    return Uri.parse(path);
}

public String getRealPathFromURI(Uri uri) {
    String path = "";
    if (getContentResolver() != null) {
        Cursor cursor = getContentResolver().query(uri, null, null, null, null);
        if (cursor != null) {
            cursor.moveToFirst();
            int idx = cursor.getColumnIndex(MediaStore.Images.ImageColumns.DATA);
            path = cursor.getString(idx);
            cursor.close();
        }
    }
    return path;
}

And check log

Edit:

Lots of people are asking how to not get a thumbnail. You need to add this code instead for the getImageUri method:

public Uri getImageUri(Context inContext, Bitmap inImage) {
    Bitmap OutImage = Bitmap.createScaledBitmap(inImage, 1000, 1000,true);
    String path = MediaStore.Images.Media.insertImage(inContext.getContentResolver(), OutImage, "Title", null);
    return Uri.parse(path);
}

The other method Compresses the file. You can adjust the size by changing the number 1000,1000

C# - Fill a combo box with a DataTable

This line

mnuActionLanguage.ComboBox.DisplayMember = "Lang.Language";

is wrong. Change it to

mnuActionLanguage.ComboBox.DisplayMember = "Language";

and it will work (even without DataBind()).

Hidden Columns in jqGrid

This thread is pretty old I suppose, but in case anyone else stumbles across this question... I had to grab a value from the selected row of a table, but I didn't want to show the column that row was from. I used hideCol, but had the same problem as Andy where it looked messy. To fix it (call it a hack) I just re-set the width of the grid.

jQuery(document).ready(function() {

       jQuery("#ItemGrid").jqGrid({ 
                ..., 
                width: 700,
                ...
        }).hideCol('StoreId').setGridWidth(700)

Since my row widths are automatic, when I reset the width of the table it reset the column widths but excluded the hidden one, so they filled in the gap.

Android Fragment no view found for ID?

I got this error when I upgraded from com.android.support:support-v4:21.0.0 to com.android.support:support-v4:22.1.1.

I had to change my layout from this:

<?xml version="1.0" encoding="utf-8"?>
<FrameLayout xmlns:android="http://schemas.android.com/apk/res/android"
    android:id="@+id/container_frame_layout"
    android:layout_width="match_parent"
    android:layout_height="match_parent">
</FrameLayout> 

To this:

<?xml version="1.0" encoding="utf-8"?>
<FrameLayout xmlns:android="http://schemas.android.com/apk/res/android"
    android:layout_width="match_parent"
    android:layout_height="match_parent">

    <FrameLayout
        android:id="@+id/container_frame_layout"
        android:layout_width="match_parent"
        android:layout_height="match_parent">
    </FrameLayout>

</FrameLayout> 

So the layout MUST have a child view. I'm assuming they enforced this in the new library.

C++ display stack trace on exception

AFAIK libunwind is quite portable and so far I haven't found anything easier to use.

How to use org.apache.commons package?

You are supposed to download the jar files that contain these libraries. Libraries may be used by adding them to the classpath.

For Commons Net you need to download the binary files from Commons Net download page. Then you have to extract the file and add the commons-net-2-2.jar file to some location where you can access it from your application e.g. to /lib.

If you're running your application from the command-line you'll have to define the classpath in the java command: java -cp .;lib/commons-net-2-2.jar myapp. More info about how to set the classpath can be found from Oracle documentation. You must specify all directories and jar files you'll need in the classpath excluding those implicitely provided by the Java runtime. Notice that there is '.' in the classpath, it is used to include the current directory in case your compiled class is located in the current directory.

For more advanced reading, you might want to read about how to define the classpath for your own jar files, or the directory structure of a war file when you're creating a web application.

If you are using an IDE, such as Eclipse, you have to remember to add the library to your build path before the IDE will recognize it and allow you to use the library.

How do you set CMAKE_C_COMPILER and CMAKE_CXX_COMPILER for building Assimp for iOS?

Option 1:

You can set CMake variables at command line like this:

cmake -D CMAKE_C_COMPILER="/path/to/your/c/compiler/executable" -D CMAKE_CXX_COMPILER "/path/to/your/cpp/compiler/executable" /path/to/directory/containing/CMakeLists.txt

See this to learn how to create a CMake cache entry.


Option 2:

In your shell script build_ios.sh you can set environment variables CC and CXX to point to your C and C++ compiler executable respectively, example:

export CC=/path/to/your/c/compiler/executable
export CXX=/path/to/your/cpp/compiler/executable
cmake /path/to/directory/containing/CMakeLists.txt

Option 3:

Edit the CMakeLists.txt file of "Assimp": Add these lines at the top (must be added before you use project() or enable_language() command)

set(CMAKE_C_COMPILER "/path/to/your/c/compiler/executable")
set(CMAKE_CXX_COMPILER "/path/to/your/cpp/compiler/executable")

See this to learn how to use set command in CMake. Also this is a useful resource for understanding use of some of the common CMake variables.


Here is the relevant entry from the official FAQ: https://gitlab.kitware.com/cmake/community/wikis/FAQ#how-do-i-use-a-different-compiler

What is the logic behind the "using" keyword in C++?

In C++11, the using keyword when used for type alias is identical to typedef.

7.1.3.2

A typedef-name can also be introduced by an alias-declaration. The identifier following the using keyword becomes a typedef-name and the optional attribute-specifier-seq following the identifier appertains to that typedef-name. It has the same semantics as if it were introduced by the typedef specifier. In particular, it does not define a new type and it shall not appear in the type-id.

Bjarne Stroustrup provides a practical example:

typedef void (*PFD)(double);    // C style typedef to make `PFD` a pointer to a function returning void and accepting double
using PF = void (*)(double);    // `using`-based equivalent of the typedef above
using P = [](double)->void; // using plus suffix return type, syntax error
using P = auto(double)->void // Fixed thanks to DyP

Pre-C++11, the using keyword can bring member functions into scope. In C++11, you can now do this for constructors (another Bjarne Stroustrup example):

class Derived : public Base { 
public: 
    using Base::f;    // lift Base's f into Derived's scope -- works in C++98
    void f(char);     // provide a new f 
    void f(int);      // prefer this f to Base::f(int) 

    using Base::Base; // lift Base constructors Derived's scope -- C++11 only
    Derived(char);    // provide a new constructor 
    Derived(int);     // prefer this constructor to Base::Base(int) 
    // ...
}; 

Ben Voight provides a pretty good reason behind the rationale of not introducing a new keyword or new syntax. The standard wants to avoid breaking old code as much as possible. This is why in proposal documents you will see sections like Impact on the Standard, Design decisions, and how they might affect older code. There are situations when a proposal seems like a really good idea but might not have traction because it would be too difficult to implement, too confusing, or would contradict old code.


Here is an old paper from 2003 n1449. The rationale seems to be related to templates. Warning: there may be typos due to copying over from PDF.

First let’s consider a toy example:

template <typename T>
class MyAlloc {/*...*/};

template <typename T, class A>
class MyVector {/*...*/};

template <typename T>

struct Vec {
typedef MyVector<T, MyAlloc<T> > type;
};
Vec<int>::type p; // sample usage

The fundamental problem with this idiom, and the main motivating fact for this proposal, is that the idiom causes the template parameters to appear in non-deducible context. That is, it will not be possible to call the function foo below without explicitly specifying template arguments.

template <typename T> void foo (Vec<T>::type&);

So, the syntax is somewhat ugly. We would rather avoid the nested ::type We’d prefer something like the following:

template <typename T>
using Vec = MyVector<T, MyAlloc<T> >; //defined in section 2 below
Vec<int> p; // sample usage

Note that we specifically avoid the term “typedef template” and introduce the new syntax involving the pair “using” and “=” to help avoid confusion: we are not defining any types here, we are introducing a synonym (i.e. alias) for an abstraction of a type-id (i.e. type expression) involving template parameters. If the template parameters are used in deducible contexts in the type expression then whenever the template alias is used to form a template-id, the values of the corresponding template parameters can be deduced – more on this will follow. In any case, it is now possible to write generic functions which operate on Vec<T> in deducible context, and the syntax is improved as well. For example we could rewrite foo as:

template <typename T> void foo (Vec<T>&);

We underscore here that one of the primary reasons for proposing template aliases was so that argument deduction and the call to foo(p) will succeed.


The follow-up paper n1489 explains why using instead of using typedef:

It has been suggested to (re)use the keyword typedef — as done in the paper [4] — to introduce template aliases:

template<class T> 
    typedef std::vector<T, MyAllocator<T> > Vec;

That notation has the advantage of using a keyword already known to introduce a type alias. However, it also displays several disavantages among which the confusion of using a keyword known to introduce an alias for a type-name in a context where the alias does not designate a type, but a template; Vec is not an alias for a type, and should not be taken for a typedef-name. The name Vec is a name for the family std::vector< [bullet] , MyAllocator< [bullet] > > – where the bullet is a placeholder for a type-name. Consequently we do not propose the “typedef” syntax. On the other hand the sentence

template<class T>
    using Vec = std::vector<T, MyAllocator<T> >;

can be read/interpreted as: from now on, I’ll be using Vec<T> as a synonym for std::vector<T, MyAllocator<T> >. With that reading, the new syntax for aliasing seems reasonably logical.

I think the important distinction is made here, aliases instead of types. Another quote from the same document:

An alias-declaration is a declaration, and not a definition. An alias- declaration introduces a name into a declarative region as an alias for the type designated by the right-hand-side of the declaration. The core of this proposal concerns itself with type name aliases, but the notation can obviously be generalized to provide alternate spellings of namespace-aliasing or naming set of overloaded functions (see ? 2.3 for further discussion). [My note: That section discusses what that syntax can look like and reasons why it isn't part of the proposal.] It may be noted that the grammar production alias-declaration is acceptable anywhere a typedef declaration or a namespace-alias-definition is acceptable.

Summary, for the role of using:

  • template aliases (or template typedefs, the former is preferred namewise)
  • namespace aliases (i.e., namespace PO = boost::program_options and using PO = ... equivalent)
  • the document says A typedef declaration can be viewed as a special case of non-template alias-declaration. It's an aesthetic change, and is considered identical in this case.
  • bringing something into scope (for example, namespace std into the global scope), member functions, inheriting constructors

It cannot be used for:

int i;
using r = i; // compile-error

Instead do:

using r = decltype(i);

Naming a set of overloads.

// bring cos into scope
using std::cos;

// invalid syntax
using std::cos(double);

// not allowed, instead use Bjarne Stroustrup function pointer alias example
using test = std::cos(double);

How do I set a VB.Net ComboBox default value

Another good method for setting a DropDownList style combobox:

Combox1.SelectedIndex = Combox1.FindStringExact("test1")

How to put a UserControl into Visual Studio toolBox

The issue with my designer was 32 vs 64 bit issue. I could add the control to tool box after following the instructions in Cannot add Controls from 64-bit Assemblies to the Toolbox or Use in Designers Within the Visual Studio IDE MS KB article.

PHP max_input_vars

Have just attempted this fix with 5.3.3 and there's no change. Googling around I found this web page http://anothersysadmin.wordpress.com/2012/02/16/php-5-3-max_input_vars-and-big-forms/ detailing other settings which need changing if your server uses the Suhosin patch which Apache under Debian does.

The site explains:

So, if you want to increase this number to, say, 3000 from the default number which is 1000, you have to put in your php.ini these lines:

max_input_vars = 3000 suhosin.post.max_vars = 3000 suhosin.request.max_vars = 3000

I tested it (added settings to php.ini both in /etc/php5/apache2 and /etc/php5/cli, and restarted Apache successfully) but still no max_input_vars variable in phpinfo.

A few sites point to PHP 5.3.9 as the first PHP version in which this change will take, so my fault for not RTM properly in the first place, although I'm interested to see people reporting it working in version above 5.3.3 but below 5.3.9.

Can't drop table: A foreign key constraint fails

This should do the trick:

SET FOREIGN_KEY_CHECKS=0; DROP TABLE bericht; SET FOREIGN_KEY_CHECKS=1;

As others point out, this is almost never what you want, even though it's whats asked in the question. A more safe solution is to delete the tables depending on bericht before deleting bericht. See CloudyMarble answer on how to do that. I use bash and the method in my post to drop all tables in a database when I don't want to or can't delete and recreate the database itself.

The #1217 error happens when other tables has foreign key constraints to the table you are trying to delete and you are using the InnoDB database engine. This solution temporarily disables checking the restraints and then re-enables them. Read the documentation for more. Be sure to delete foreign key restraints and fields in tables depending on bericht, otherwise you might leave your database in a broken state.

Php multiple delimiters in explode

Simply you can use the following code:

$arr=explode('sep1',str_replace(array('sep2','sep3','sep4'),'sep1',$mystring));

HashMap to return default value for non-found keys?

Java 8 introduced a nice computeIfAbsent default method to Map interface which stores lazy-computed value and so doesn't break map contract:

Map<Key, Graph> map = new HashMap<>();
map.computeIfAbsent(aKey, key -> createExpensiveGraph(key));

Origin: http://blog.javabien.net/2014/02/20/loadingcache-in-java-8-without-guava/

Disclamer: This answer doesn't match exactly what OP asked but may be handy in some cases matching question's title when keys number is limited and caching of different values would be profitable. It shouldn't be used in opposite case with plenty of keys and same default value as this would needlessly waste memory.

What is the attribute property="og:title" inside meta tag?

og:title is one of the open graph meta tags. og:... properties define objects in a social graph. They are used for example by Facebook.

og:title stands for the title of your object as it should appear within the graph (see here for more http://ogp.me/ )

Current date and time as string

Non C++11 solution: With the <ctime> header, you could use strftime. Make sure your buffer is large enough, you wouldn't want to overrun it and wreak havoc later.

#include <iostream>
#include <ctime>

int main ()
{
  time_t rawtime;
  struct tm * timeinfo;
  char buffer[80];

  time (&rawtime);
  timeinfo = localtime(&rawtime);

  strftime(buffer,sizeof(buffer),"%d-%m-%Y %H:%M:%S",timeinfo);
  std::string str(buffer);

  std::cout << str;

  return 0;
}

Convert blob URL to normal URL

another way to create a data url from blob url may be using canvas.

var canvas = document.createElement("canvas")
var context = canvas.getContext("2d")
context.drawImage(img, 0, 0) // i assume that img.src is your blob url
var dataurl = canvas.toDataURL("your prefer type", your prefer quality)

as what i saw in mdn, canvas.toDataURL is supported well by browsers. (except ie<9, always ie<9)

AngularJS How to dynamically add HTML and bind to controller

For those, like me, who did not have the possibility to use angular directive and were "stuck" outside of the angular scope, here is something that might help you.

After hours searching on the web and on the angular doc, I have created a class that compiles HTML, place it inside a targets, and binds it to a scope ($rootScope if there is no $scope for that element)

/**
 * AngularHelper : Contains methods that help using angular without being in the scope of an angular controller or directive
 */
var AngularHelper = (function () {
    var AngularHelper = function () { };

    /**
     * ApplicationName : Default application name for the helper
     */
    var defaultApplicationName = "myApplicationName";

    /**
     * Compile : Compile html with the rootScope of an application
     *  and replace the content of a target element with the compiled html
     * @$targetDom : The dom in which the compiled html should be placed
     * @htmlToCompile : The html to compile using angular
     * @applicationName : (Optionnal) The name of the application (use the default one if empty)
     */
    AngularHelper.Compile = function ($targetDom, htmlToCompile, applicationName) {
        var $injector = angular.injector(["ng", applicationName || defaultApplicationName]);

        $injector.invoke(["$compile", "$rootScope", function ($compile, $rootScope) {
            //Get the scope of the target, use the rootScope if it does not exists
            var $scope = $targetDom.html(htmlToCompile).scope();
            $compile($targetDom)($scope || $rootScope);
            $rootScope.$digest();
        }]);
    }

    return AngularHelper;
})();

It covered all of my cases, but if you find something that I should add to it, feel free to comment or edit.

Hope it will help.

SQL join format - nested inner joins

For readability, I restructured the query... starting with the apparent top-most level being Table1, which then ties to Table3, and then table3 ties to table2. Much easier to follow if you follow the chain of relationships.

Now, to answer your question. You are getting a large count as the result of a Cartesian product. For each record in Table1 that matches in Table3 you will have X * Y. Then, for each match between table3 and Table2 will have the same impact... Y * Z... So your result for just one possible ID in table 1 can have X * Y * Z records.

This is based on not knowing how the normalization or content is for your tables... if the key is a PRIMARY key or not..

Ex:
Table 1       
DiffKey    Other Val
1          X
1          Y
1          Z

Table 3
DiffKey   Key    Key2  Tbl3 Other
1         2      6     V
1         2      6     X
1         2      6     Y
1         2      6     Z

Table 2
Key    Key2   Other Val
2      6      a
2      6      b
2      6      c
2      6      d
2      6      e

So, Table 1 joining to Table 3 will result (in this scenario) with 12 records (each in 1 joined with each in 3). Then, all that again times each matched record in table 2 (5 records)... total of 60 ( 3 tbl1 * 4 tbl3 * 5 tbl2 )count would be returned.

So, now, take that and expand based on your 1000's of records and you see how a messed-up structure could choke a cow (so-to-speak) and kill performance.

SELECT
      COUNT(*)
   FROM
      Table1 
         INNER JOIN Table3
            ON Table1.DifferentKey = Table3.DifferentKey
            INNER JOIN Table2
               ON Table3.Key =Table2.Key
               AND Table3.Key2 = Table2.Key2 

how to play video from url

It has something to do with your link and content. Try the following two links:

    String path="http://www.ted.com/talks/download/video/8584/talk/761";
    String path1="http://commonsware.com/misc/test2.3gp";

    Uri uri=Uri.parse(path1);

    VideoView video=(VideoView)findViewById(R.id.VideoView01);
    video.setVideoURI(uri);
    video.start();

Start with "path1", it is a small light weight video stream and then try the "path", it is a higher resolution than "path1", a perfect high resolution for the mobile phone.

Multiple variables in a 'with' statement?

contextlib.nested supports this:

import contextlib

with contextlib.nested(open("out.txt","wt"), open("in.txt")) as (file_out, file_in):

   ...

Update:
To quote the documentation, regarding contextlib.nested:

Deprecated since version 2.7: The with-statement now supports this functionality directly (without the confusing error prone quirks).

See Rafal Dowgird's answer for more information.

Easy way to write contents of a Java InputStream to an OutputStream

you can use this method

public static void copyStream(InputStream is, OutputStream os)
 {
     final int buffer_size=1024;
     try
     {
         byte[] bytes=new byte[buffer_size];
         for(;;)
         {
           int count=is.read(bytes, 0, buffer_size);
           if(count==-1)
               break;
           os.write(bytes, 0, count);
         }
     }
     catch(Exception ex){}
 }

R: "Unary operator error" from multiline ggplot2 command

This is a well-known nuisance when posting multiline commands in R. (You can get different behavior when you source() a script to when you copy-and-paste the lines, both with multiline and comments)

Rule: always put the dangling '+' at the end of a line so R knows the command is unfinished:

ggplot(...) + geom_whatever1(...) +
  geom_whatever2(...) +
  stat_whatever3(...) +
  geom_title(...) + scale_y_log10(...)

Don't put the dangling '+' at the start of the line, since that tickles the error:

Error in "+ geom_whatever2(...) invalid argument to unary operator"

And obviously don't put dangling '+' at both end and start since that's a syntax error.

So, learn a habit of being consistent: always put '+' at end-of-line.

cf. answer to "Split code over multiple lines in an R script"

Command CompileSwift failed with a nonzero exit code in Xcode 10

I attempted

  • Closing & Reopening Xcode
  • Cleaning Build Folder
  • Running pod install --repo-update

and all of these still did not fix the problem.

Restarting the Mac did the trick!

How to get the current working directory in Java?

Mention that it is checked only in Windows but i think it works perfect on other Operating Systems [Linux,MacOs,Solaris] :).


I had 2 .jar files in the same directory . I wanted from the one .jar file to start the other .jar file which is in the same directory.

The problem is that when you start it from the cmd the current directory is system32.


Warnings!

  • The below seems to work pretty well in all the test i have done even with folder name ;][[;'57f2g34g87-8+9-09!2#@!$%^^&() or ()%&$%^@# it works well.
  • I am using the ProcessBuilder with the below as following:

..

//The class from which i called this was the class `Main`
String path = getBasePathForClass(Main.class);
String applicationPath=  new File(path + "application.jar").getAbsolutePath();


System.out.println("Directory Path is : "+applicationPath);

//Your know try catch here
//Mention that sometimes it doesn't work for example with folder `;][[;'57f2g34g87-8+9-09!2#@!$%^^&()` 
ProcessBuilder builder = new ProcessBuilder("java", "-jar", applicationPath);
builder.redirectErrorStream(true);
Process process = builder.start();

//...code

getBasePathForClass(Class<?> classs):

    /**
     * Returns the absolute path of the current directory in which the given
     * class
     * file is.
     * 
     * @param classs
     * @return The absolute path of the current directory in which the class
     *         file is.
     * @author GOXR3PLUS[StackOverFlow user] + bachden [StackOverFlow user]
     */
    public static final String getBasePathForClass(Class<?> classs) {

        // Local variables
        File file;
        String basePath = "";
        boolean failed = false;

        // Let's give a first try
        try {
            file = new File(classs.getProtectionDomain().getCodeSource().getLocation().toURI().getPath());

            if (file.isFile() || file.getPath().endsWith(".jar") || file.getPath().endsWith(".zip")) {
                basePath = file.getParent();
            } else {
                basePath = file.getPath();
            }
        } catch (URISyntaxException ex) {
            failed = true;
            Logger.getLogger(classs.getName()).log(Level.WARNING,
                    "Cannot firgue out base path for class with way (1): ", ex);
        }

        // The above failed?
        if (failed) {
            try {
                file = new File(classs.getClassLoader().getResource("").toURI().getPath());
                basePath = file.getAbsolutePath();

                // the below is for testing purposes...
                // starts with File.separator?
                // String l = local.replaceFirst("[" + File.separator +
                // "/\\\\]", "")
            } catch (URISyntaxException ex) {
                Logger.getLogger(classs.getName()).log(Level.WARNING,
                        "Cannot firgue out base path for class with way (2): ", ex);
            }
        }

        // fix to run inside eclipse
        if (basePath.endsWith(File.separator + "lib") || basePath.endsWith(File.separator + "bin")
                || basePath.endsWith("bin" + File.separator) || basePath.endsWith("lib" + File.separator)) {
            basePath = basePath.substring(0, basePath.length() - 4);
        }
        // fix to run inside netbeans
        if (basePath.endsWith(File.separator + "build" + File.separator + "classes")) {
            basePath = basePath.substring(0, basePath.length() - 14);
        }
        // end fix
        if (!basePath.endsWith(File.separator)) {
            basePath = basePath + File.separator;
        }
        return basePath;
    }

Using port number in Windows host file

I managed to achieve this by using Windows included Networking tool netsh.

As Mat points out : The hosts file is for host name resolution only, so a combination of the two did the trick for me.

Example


Overview

example.app:80
 |                           <--Link by Hosts File
 +--> 127.65.43.21:80
       |                     <--Link by netsh Utility
       +--> localhost:8081

Actions

  • Started my server on localhost:8081
  • Added my "local DNS" in the hosts file as a new line
    • 127.65.43.21 example.app
      • Any free address in the network 127.0.0.0/8 (127.x.x.x) can be used.
      • Note: I am assuming 127.65.43.21:80 is not occupied by another service.
      • You can check with netstat -a -n -p TCP | grep "LISTENING"
  • added the following network configuration with netsh command utility
    • netsh interface portproxy add v4tov4 listenport=80 listenaddress=127.65.43.21 connectport=8081 connectaddress=127.0.0.1
  • I can now access the server at http://example.app

Notes:
- These commands/file modifications need to be executed with Admin rights

- netsh portproxy needs ipv6 libraries even only to use v4tov4, typically they will also be included by default, otherwise install them using the following command: netsh interface ipv6 install


You can see the entry you have added with the command:

netsh interface portproxy show v4tov4

You can remove the entry with the following command:

netsh interface portproxy delete v4tov4 listenport=80 listenaddress=127.65.43.21


Links to Resources:

Why would a JavaScript variable start with a dollar sign?

The $ character has no special meaning to the JavaScript engine. It's just another valid character in a variable name like a-z, A-Z, _, 0-9, etc...

How to count the occurrence of certain item in an ndarray?

Try this:

a = np.array([0, 0, 0, 1, 0, 1, 1, 0, 0, 0, 0, 1])
list(a).count(1)

List all devices, partitions and volumes in Powershell

On Windows Powershell:

Get-PSDrive 
[System.IO.DriveInfo]::getdrives()
wmic diskdrive
wmic volume

Also the utility dskwipe: http://smithii.com/dskwipe

dskwipe.exe -l

AngularJS: How to run additional code after AngularJS has rendered a template?

Finally i found the solution, i was using a REST service to update my collection. In order to convert datatable jquery is the follow code:

$scope.$watchCollection( 'conferences', function( old, nuew ) {
        if( old === nuew ) return;
        $( '#dataTablex' ).dataTable().fnDestroy();
        $timeout(function () {
                $( '#dataTablex' ).dataTable();
        });
    });

Basic Apache commands for a local Windows machine

For frequent uses of this command I found it easy to add the location of C:\xampp\apache\bin to the PATH. Use whatever directory you have this installed in.

Then you can run from any directory in command line:

httpd -k restart

The answer above that suggests httpd -k -restart is actually a typo. You can see the commands by running httpd /?

Find duplicate records in MongoDB

db.getCollection('orders').aggregate([  
    {$group: { 
            _id: {name: "$name"},
            uniqueIds: {$addToSet: "$_id"},
            count: {$sum: 1}
        } 
    },
    {$match: { 
        count: {"$gt": 1}
        }
    }
])

First Group Query the group according to the fields.

Then we check the unique Id and count it, If count is greater then 1 then the field is duplicate in the entire collection so that thing is to be handle by $match query.

Downloading an entire S3 bucket?

If you use Visual Studio, download "AWS Toolkit for Visual Studio".

After installed, go to Visual Studio - AWS Explorer - S3 - Your bucket - Double click

In the window you will be able to select all files. Right click and download files.

How to create table using select query in SQL Server?

select <column list> into <dest. table> from <source table>;

You could do this way.

SELECT windows_release, windows_service_pack_level, 
       windows_sku, os_language_version
into   new_table_name
FROM   sys.dm_os_windows_info OPTION (RECOMPILE);

SHA512 vs. Blowfish and Bcrypt

I would recommend Ulrich Drepper's SHA-256/SHA-512 based crypt implementation.

We ported these algorithms to Java, and you can find a freely licensed version of them at ftp://ftp.arlut.utexas.edu/java_hashes/.

Note that most modern (L)Unices support Drepper's algorithm in their /etc/shadow files.

How can I programmatically check whether a keyboard is present in iOS app?

To check weather keyboard is appeared, we can use the Keyboard predefined notifications.

UIKeyboardDidShowNotification ,UIKeyboardDidHideNotification

For example I can use the following code to listen the keyboard notification

// Listen for keyboard appearances and disappearances

[[NSNotificationCenter defaultCenter] addObserver:self 
                                         selector:@selector(keyboardDidShow:)
                                             name:UIKeyboardDidShowNotification
                                           object:nil];

[[NSNotificationCenter defaultCenter] addObserver:self
                                         selector:@selector(keyboardDidHide:)
                                             name:UIKeyboardDidHideNotification
                                           object:nil];

in the methods I can get notifications

- (void)keyboardDidShow: (NSNotification *) notifyKeyBoardShow{
    // key board is closed
}

- (void)keyboardDidHide: (NSNotification *) notifyKeyBoardHide{
    // key board is opened
}

How do I remove an object from an array with JavaScript?

delete obj[1];

Note that this will not change array indices. Any array members you delete will remain as "slots" that contain undefined.

Open mvc view in new window from controller

You're asking the wrong question. The codebehind (controller) has nothing to do with what the frontend does. In fact, that's the strength of MVC -- you separate the code/concept from the view.

If you want an action to open in a new window, then links to that action need to tell the browser to open a new window when clicked.

A pseudo example: <a href="NewWindow" target="_new">Click Me</a>

And that's all there is to it. Set the target of links to that action.

How do I execute a *.dll file

To Run a .dll file..First find out what are functions it is exporting..Dll files will excecute the functions specified in the Export Category..To know what function it is Exporting refer "filealyzer" Application..It will show you the export function under "PE EXPORT" Category..Notedown the function name-- Then open the command prompt,Type Rundll32 dllname,functionname (dllname--name of your dll) (Functionname-- name of the function you found under the PE Export) Note:Makesure that your command prompt location is your dll file location

How can I add a class attribute to an HTML element generated by MVC's HTML Helpers?

In order to create an anonymous type (or any type) with a property that has a reserved keyword as its name in C#, you can prepend the property name with an at sign, @:

Html.BeginForm("Foo", "Bar", FormMethod.Post, new { @class = "myclass"})

For VB.NET this syntax would be accomplished using the dot, ., which in that language is default syntax for all anonymous types:

Html.BeginForm("Foo", "Bar", FormMethod.Post, new with { .class = "myclass" })

How to use onResume()?

After an activity started, restarted (onRestart() happens before onStart()), or paused (onPause()), onResume() called. When the activity is in the state of onResume(), the activity is ready to be used by the app user.

I have studied the activity lifecycle a little bit, and here's my understanding of this topic: If you want to restart the activity (A) at the end of the execution of another, there could be a few different cases.

  1. The other activity (B) has been paused and/or stopped or destroyed, and the activity A possibly had been paused (onPause()), in this case, activity A will call onResume()

  2. The activity B has been paused and/or stopped or destroyed, the activity A possibly had been stopped (onStop()) due to memory thing, in this case, activity A will call onRestart() first, onStart() second, then onResume()

  3. The activity B has been paused and/or stopped or destroyed, the activity A has been destroyed, the programmer can call onStart() manually to start the activity first, then onResume() because when an activity is in the destroyed status the activity has not started, and this happens before the activity being completely removed. If the activity is removed, the activity needs to be created again. Manually calling onStart() I think it's because if the activity not started and it is created, onStart() will be called after onCreate().

If you want to update data, make a data update function and put the function inside the onResume(). Or put a loadData function inside onResume()

It's better to understand the lifecycle with the help of the Activity lifecycle diagram.

how to print json data in console.log

This is an old post but I'm chiming in because (as Narem briefly mentioned) a few of the printf-like features are available with the console.log formatters. In the case of the question, you can benefit from the string, number or json formatters for your data.

Examples:

console.log("Quantity %s, Price: %d", data.quantity-row_122, data.price-row_122);
console.log("Quantity and Price Data %j", data);

Working with Enums in android

Android's preferred approach is int constants enforced with @IntDef:

public static final int GENDER_MALE = 1;
public static final int GENDER_FEMALE = 2;

@Retention(RetentionPolicy.SOURCE)
@IntDef ({GENDER_MALE, GENDER_FEMALE})
public @interface Gender{}

// Example usage...
void exampleFunc(@Gender int gender) {
  switch(gender) {
  case GENDER_MALE:

     break;
  case GENDER_FEMALE:
     // TODO
     break;
  }
}

Docs: https://developer.android.com/studio/write/annotations.html#enum-annotations

change html text from link with jquery

You have to use the jquery's text() function. What it does is:

Get the combined text contents of all matched elements.

The result is a string that contains the combined text contents of all matched elements. This method works on both HTML and XML documents. Cannot be used on input elements. For input field text use the val attribute.

For example:

Find the text in the first paragraph (stripping out the html), then set the html of the last paragraph to show it is just text (the bold is gone).

var str = $("p:first").text();
$("p:last").html(str);

Test Paragraph.

Test Paragraph.

With your markup you have to do:

$('a#a_tbnotesverbergen').text('new text');

and it will result in

<a id="a_tbnotesverbergen" href="#nothing">new text</a>

Convert PEM traditional private key to PKCS8 private key

Try using following command. I haven't tried it but I think it should work.

openssl pkcs8 -topk8 -inform PEM -outform DER -in filename -out filename -nocrypt

What is PAGEIOLATCH_SH wait type in SQL Server?

PAGEIOLATCH_SH wait type usually comes up as the result of fragmented or unoptimized index.

Often reasons for excessive PAGEIOLATCH_SH wait type are:

  • I/O subsystem has a problem or is misconfigured
  • Overloaded I/O subsystem by other processes that are producing the high I/O activity
  • Bad index management
  • Logical or physical drive misconception
  • Network issues/latency
  • Memory pressure
  • Synchronous Mirroring and AlwaysOn AG

In order to try and resolve having high PAGEIOLATCH_SH wait type, you can check:

  • SQL Server, queries and indexes, as very often this could be found as a root cause of the excessive PAGEIOLATCH_SH wait types
  • For memory pressure before jumping into any I/O subsystem troubleshooting

Always keep in mind that in case of high safety Mirroring or synchronous-commit availability in AlwaysOn AG, increased/excessive PAGEIOLATCH_SH can be expected.

You can find more details about this topic in the article Handling excessive SQL Server PAGEIOLATCH_SH wait types

how to find array size in angularjs

You can find the number of members in a Javascript array by using its length property:

var number = $scope.names.length;

Docs - Array.prototype.length

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

This problems gave me great headache when i tried to use reverse for generating activation link and send it via email of course. So i think from tests.py it will be same. The correct way to do this is following:

from django.test import Client
from django.core.urlresolvers import reverse

#app name - name of the app where the url is defined
client= Client()
response = client.get(reverse('app_name:edit_project', project_id=4)) 

Simple way to query connected USB devices info in Python?

I can think of a quick code like this.

Since all USB ports can be accessed via /dev/bus/usb/< bus >/< device >

For the ID generated, even if you unplug the device and reattach it [ could be some other port ]. It will be the same.

import re
import subprocess
device_re = re.compile("Bus\s+(?P<bus>\d+)\s+Device\s+(?P<device>\d+).+ID\s(?P<id>\w+:\w+)\s(?P<tag>.+)$", re.I)
df = subprocess.check_output("lsusb")
devices = []
for i in df.split('\n'):
    if i:
        info = device_re.match(i)
        if info:
            dinfo = info.groupdict()
            dinfo['device'] = '/dev/bus/usb/%s/%s' % (dinfo.pop('bus'), dinfo.pop('device'))
            devices.append(dinfo)
print devices

Sample output here will be:

[
{'device': '/dev/bus/usb/001/009', 'tag': 'Apple, Inc. Optical USB Mouse [Mitsumi]', 'id': '05ac:0304'},
{'device': '/dev/bus/usb/001/001', 'tag': 'Linux Foundation 2.0 root hub', 'id': '1d6b:0002'},
{'device': '/dev/bus/usb/001/002', 'tag': 'Intel Corp. Integrated Rate Matching Hub', 'id': '8087:0020'},
{'device': '/dev/bus/usb/001/004', 'tag': 'Microdia ', 'id': '0c45:641d'}
]

Code Updated for Python 3

import re
import subprocess
device_re = re.compile(b"Bus\s+(?P<bus>\d+)\s+Device\s+(?P<device>\d+).+ID\s(?P<id>\w+:\w+)\s(?P<tag>.+)$", re.I)
df = subprocess.check_output("lsusb")
devices = []
for i in df.split(b'\n'):
    if i:
        info = device_re.match(i)
        if info:
            dinfo = info.groupdict()
            dinfo['device'] = '/dev/bus/usb/%s/%s' % (dinfo.pop('bus'), dinfo.pop('device'))
            devices.append(dinfo)
            
print(devices)

Programmatically go back to the previous fragment in the backstack

Add those line to your onBackPressed() Method. popBackStackImmediate() method will get you back to the previous fragment if you have any fragment on back stack `

if(getFragmentManager().getBackStackEntryCount() > 0){
     getFragmentManager().popBackStackImmediate();
}
else{
    super.onBackPressed();
}

`

How to truncate the time on a DateTime object in Python?

Here is yet another way which fits in one line but is not particularly elegant:

dt = datetime.datetime.fromordinal(datetime.date.today().toordinal())

Can I style an image's ALT text with CSS?

Sure you can!

http://jsfiddle.net/VfTGW/

I do this as a fallback for header logo images, I think some versions of IE will not abide. Edit: Or Chrome apparently - I don't even see alt text in the demo(?). Firefox works well however.

_x000D_
_x000D_
img {_x000D_
  color: green;_x000D_
  font: 40px Impact;_x000D_
}
_x000D_
<img src="404" alt="Alt Text">
_x000D_
_x000D_
_x000D_

java.lang.IllegalArgumentException: No converter found for return value of type

Use @ResponseBody and getter/setter. Hope it will solve your issue.

@RequestMapping(value = "/bar/foo", method = RequestMethod.GET)
@ResponseBody
public ResponseEntity<foo> foo() {

and update your mvc-dispatcher-servlet.xml:

<mvc:annotation-driven>
     <mvc:message-converters>
            <bean class="org.springframework.http.converter.StringHttpMessageConverter"/>
            <bean class="org.springframework.http.converter.json.MappingJackson2HttpMessageConverter"/>
   </mvc:message-converters>
</mvc:annotation-driven>

Ajax success event not working

I'm using XML to carry the result back from the php on the server to the webpage and I have had the same behaviour.

In my case the reason was , that the closing tag did not match the opening tag.

<?php
....
header("Content-Type: text/xml");
echo "<?xml version=\"1.0\" encoding=\"utf-8\"?>
    <result>
        <status>$status</status>
        <OPENING_TAG>$message</CLOSING_TAG>
    </result>";
?>

How to get first N number of elements from an array

Using a simple example:

var letters = ["a", "b", "c", "d"];
var letters_02 = letters.slice(0, 2);
console.log(letters_02)

Output: ["a", "b"]

var letters_12 = letters.slice(1, 2);
console.log(letters_12)

Output: ["b"]

Note: slice provides only a shallow copy and DOES NOT modify the original array.

C# - What does the Assert() method do? Is it still useful?

The way I think of it is Debug.Assert is a way to establish a contract about how a method is supposed to be called, focusing on specifics about the values of a paramter (instead of just the type). For example, if you are not supposed to send a null in the second parameter you add the Assert around that parameter to tell the consumer not to do that.

It prevents someone from using your code in a boneheaded way. But it also allows that boneheaded way to go through to production and not give the nasty message to a customer (assuming you build a Release build).

How to fix: Error device not found with ADB.exe

Try changing USB port. Try restarting adb server.

How can I capture the right-click event in JavaScript?

I think that you are looking for something like this:

   function rightclick() {
    var rightclick;
    var e = window.event;
    if (e.which) rightclick = (e.which == 3);
    else if (e.button) rightclick = (e.button == 2);
    alert(rightclick); // true or false, you can trap right click here by if comparison
}

(http://www.quirksmode.org/js/events_properties.html)

And then use the onmousedown even with the function rightclick() (if you want to use it globally on whole page you can do this <body onmousedown=rightclick(); >

Auto-refreshing div with jQuery - setTimeout or another method?

Another modification:

function update() {
  $.get("response.php", function(data) {
    $("#some_div").html(data);
    window.setTimeout(update, 10000);
  });
}

The difference with this is that it waits 10 seconds AFTER the ajax call is one. So really the time between refreshes is 10 seconds + length of ajax call. The benefit of this is if your server takes longer than 10 seconds to respond, you don't get two (and eventually, many) simultaneous AJAX calls happening.

Also, if the server fails to respond, it won't keep trying.

I've used a similar method in the past using .ajax to handle even more complex behaviour:

function update() {
  $("#notice_div").html('Loading..'); 
  $.ajax({
    type: 'GET',
    url: 'response.php',
    timeout: 2000,
    success: function(data) {
      $("#some_div").html(data);
      $("#notice_div").html(''); 
      window.setTimeout(update, 10000);
    },
    error: function (XMLHttpRequest, textStatus, errorThrown) {
      $("#notice_div").html('Timeout contacting server..');
      window.setTimeout(update, 60000);
    }
}

This shows a loading message while loading (put an animated gif in there for typical "web 2.0" style). If the server times out (in this case takes longer than 2s) or any other kind of error happens, it shows an error, and it waits for 60 seconds before contacting the server again.

This can be especially beneficial when doing fast updates with a larger number of users, where you don't want everyone to suddenly cripple a lagging server with requests that are all just timing out anyways.

Getting the parameters of a running JVM

I am adding this new answer because as per JDK8 documentation jcmd is suggested approach now.

It is suggested to use the latest utility, jcmd instead of the previous jstack, jinfo, and jmap utilities for enhanced diagnostics and reduced performance overhead.

Below are commands to get your properties/flags you want.

jcmd pid VM.system_properties
jcmd pid VM.flags

We need pid, for this use jcmd -l, like below

username@users-Air:~/javacode$ jcmd -l 
11441 Test 
6294 Test 
29197 jdk.jcmd/sun.tools.jcmd.JCmd -l 

Now time to use these pids to get properties/flags you want

Command: jcmd 11441 VM.system_properties

11441:
#Tue Oct 17 12:44:50 IST 2017
gopherProxySet=false
awt.toolkit=sun.lwawt.macosx.LWCToolkit
file.encoding.pkg=sun.io
java.specification.version=9
sun.cpu.isalist=
sun.jnu.encoding=UTF-8
java.class.path=.
java.vm.vendor=Oracle Corporation
sun.arch.data.model=64
java.vendor.url=http\://java.oracle.com/
user.timezone=Asia/Kolkata
java.vm.specification.version=9
os.name=Mac OS X
sun.java.launcher=SUN_STANDARD
user.country=US
sun.boot.library.path=/Library/Java/JavaVirtualMachines/jdk-9.jdk/Contents/Home/lib
sun.java.command=Test
http.nonProxyHosts=local|*.local|169.254/16|*.169.254/16
jdk.debug=release
sun.cpu.endian=little
user.home=/Users/XXXX
user.language=en
java.specification.vendor=Oracle Corporation
java.home=/Library/Java/JavaVirtualMachines/jdk-9.jdk/Contents/Home
file.separator=/
java.vm.compressedOopsMode=Zero based
line.separator=\n
java.specification.name=Java Platform API Specification
java.vm.specification.vendor=Oracle Corporation
java.awt.graphicsenv=sun.awt.CGraphicsEnvironment
sun.management.compiler=HotSpot 64-Bit Tiered Compilers
ftp.nonProxyHosts=local|*.local|169.254/16|*.169.254/16
java.runtime.version=9+181
user.name=XXXX
path.separator=\:
os.version=10.12.6
java.runtime.name=Java(TM) SE Runtime Environment
file.encoding=UTF-8
java.vm.name=Java HotSpot(TM) 64-Bit Server VM
java.vendor.url.bug=http\://bugreport.java.com/bugreport/
java.io.tmpdir=/var/folders/dm/gd6lc90d0hg220lzw_m7krr00000gn/T/
java.version=9
user.dir=/Users/XXXX/javacode
os.arch=x86_64
java.vm.specification.name=Java Virtual Machine Specification
java.awt.printerjob=sun.lwawt.macosx.CPrinterJob
sun.os.patch.level=unknown
MyParam=2
java.library.path=/Users/XXXX/Library/Java/Extensions\:/Library/Java/Extensions\:/Network/Library/Java/Extensions\:/System/Library/Java/Extensions\:/usr/lib/java\:.
java.vm.info=mixed mode
java.vendor=Oracle Corporation
java.vm.version=9+181
sun.io.unicode.encoding=UnicodeBig
java.class.version=53.0
socksNonProxyHosts=local|*.local|169.254/16|*.169.254/16

Command : jcmd 11441 VM.flags output:

11441:
-XX:CICompilerCount=3 -XX:ConcGCThreads=1 -XX:G1ConcRefinementThreads=4 -XX:G1HeapRegionSize=1048576 -XX:InitialHeapSize=67108864 -XX:MarkStackSize=4194304 -XX:MaxHeapSize=1073741824 -XX:MaxNewSize=643825664 -XX:MinHeapDeltaBytes=1048576 -XX:NonNMethodCodeHeapSize=5830092 -XX:NonProfiledCodeHeapSize=122914074 -XX:ProfiledCodeHeapSize=122914074 -XX:ReservedCodeCacheSize=251658240 -XX:+SegmentedCodeCache -XX:-UseAOT -XX:+UseCompressedClassPointers -XX:+UseCompressedOops -XX:+UseFastUnorderedTimeStamps -XX:+UseG1GC 

For more instructions of usages of jcmd, see my blog post

Prepend line to beginning of a file

In modes 'a' or 'a+', any writing is done at the end of the file, even if at the current moment when the write() function is triggered the file's pointer is not at the end of the file: the pointer is moved to the end of file before any writing. You can do what you want in two manners.

1st way, can be used if there are no issues to load the file into memory:

def line_prepender(filename, line):
    with open(filename, 'r+') as f:
        content = f.read()
        f.seek(0, 0)
        f.write(line.rstrip('\r\n') + '\n' + content)

2nd way:

def line_pre_adder(filename, line_to_prepend):
    f = fileinput.input(filename, inplace=1)
    for xline in f:
        if f.isfirstline():
            print line_to_prepend.rstrip('\r\n') + '\n' + xline,
        else:
            print xline,

I don't know how this method works under the hood and if it can be employed on big big file. The argument 1 passed to input is what allows to rewrite a line in place; the following lines must be moved forwards or backwards in order that the inplace operation takes place, but I don't know the mechanism

jQuery when element becomes visible

I just Improved ProllyGeek`s answer

Someone may find it useful. you can access displayChanged(event, state) event when .show(), .hide() or .toggle() is called on element

(function() {
  var eventDisplay = new $.Event('displayChanged'),
    origShow = $.fn.show,
    origHide = $.fn.hide;
  //
  $.fn.show = function() {
    origShow.apply(this, arguments);
    $(this).trigger(eventDisplay,['show']);
  };
  //
  $.fn.hide = function() {
    origHide.apply(this, arguments);
    $(this).trigger(eventDisplay,['hide']);
  };
  //
})();

$('#header').on('displayChanged', function(e,state) {
      console.log(state);
});

$('#header').toggle(); // .show() .hide() supported

How to generate service reference with only physical wsdl file

There are two ways to go about this. You can either use the IDE to generate a WSDL, or you can do it via the command line.

1. To create it via the IDE:

In the solution explorer pane, right click on the project that you would like to add the Service to:

enter image description here

Then, you can enter the path to your service WSDL and hit go:

enter image description here

2. To create it via the command line:

Open a VS 2010 Command Prompt (Programs -> Visual Studio 2010 -> Visual Studio Tools)
Then execute:

WSDL /verbose C:\path\to\wsdl

WSDL.exe will then output a .cs file for your consumption.

If you have other dependencies that you received with the file, such as xsd's, add those to the argument list:

WSDL /verbose C:\path\to\wsdl C:\path\to\some\xsd C:\path\to\some\xsd

If you need VB output, use /language:VB in addition to the /verbose.

JavaScript alert box with timer

setTimeout( function ( ) { alert( "moo" ); }, 10000 ); //displays msg in 10 seconds

Convert cells(1,1) into "A1" and vice versa

The Address property of a cell can get this for you:

MsgBox Cells(1, 1).Address(RowAbsolute:=False, ColumnAbsolute:=False)

returns A1.

The other way around can be done with the Row and Column property of Range:

MsgBox Range("A1").Row & ", " & Range("A1").Column

returns 1,1.

Compare data of two Excel Columns A & B, and show data of Column A that do not exist in B

Put this in C2 and copy down

=IF(ISNA(VLOOKUP(A2,$B$2:$B$65535,1,FALSE)),"not in B","")

Then if the value in A isn't in B the cell in column C will say "not in B".

tslint / codelyzer / ng lint error: "for (... in ...) statements must be filtered with an if statement"

use Object.keys:

Object.keys(this.formErrors).map(key => {
  this.formErrors[key] = '';
  const control = form.get(key);

  if(control && control.dirty && !control.valid) {
    const messages = this.validationMessages[key];
    Object.keys(control.errors).map(key2 => {
      this.formErrors[key] += messages[key2] + ' ';
    });
  }
});

Python iterating through object attributes

You can use the standard Python idiom, vars():

for attr, value in vars(k).items():
    print(attr, '=', value)

Convert Xml to Table SQL Server

This is the answer, hope it helps someone :)

First there are two variations on how the xml can be written:

1

<row>
    <IdInvernadero>8</IdInvernadero>
    <IdProducto>3</IdProducto>
    <IdCaracteristica1>8</IdCaracteristica1>
    <IdCaracteristica2>8</IdCaracteristica2>
    <Cantidad>25</Cantidad>
    <Folio>4568457</Folio>
</row>
<row>
    <IdInvernadero>3</IdInvernadero>
    <IdProducto>3</IdProducto>
    <IdCaracteristica1>1</IdCaracteristica1>
    <IdCaracteristica2>2</IdCaracteristica2>
    <Cantidad>72</Cantidad>
    <Folio>4568457</Folio>
</row>

Answer:

SELECT  
       Tbl.Col.value('IdInvernadero[1]', 'smallint'),  
       Tbl.Col.value('IdProducto[1]', 'smallint'),  
       Tbl.Col.value('IdCaracteristica1[1]', 'smallint'),
       Tbl.Col.value('IdCaracteristica2[1]', 'smallint'),
       Tbl.Col.value('Cantidad[1]', 'int'),
       Tbl.Col.value('Folio[1]', 'varchar(7)')
FROM   @xml.nodes('//row') Tbl(Col)  

2.

<row IdInvernadero="8" IdProducto="3" IdCaracteristica1="8" IdCaracteristica2="8" Cantidad ="25" Folio="4568457" />                         
<row IdInvernadero="3" IdProducto="3" IdCaracteristica1="1" IdCaracteristica2="2" Cantidad ="72" Folio="4568457" />

Answer:

SELECT  
       Tbl.Col.value('@IdInvernadero', 'smallint'),  
       Tbl.Col.value('@IdProducto', 'smallint'),  
       Tbl.Col.value('@IdCaracteristica1', 'smallint'),
       Tbl.Col.value('@IdCaracteristica2', 'smallint'),
       Tbl.Col.value('@Cantidad', 'int'),
       Tbl.Col.value('@Folio', 'varchar(7)')

FROM   @xml.nodes('//row') Tbl(Col)

Taken from:

  1. http://kennyshu.blogspot.com/2007/12/convert-xml-file-to-table-in-sql-2005.html

  2. http://msdn.microsoft.com/en-us/library/ms345117(SQL.90).aspx

Error - replacement has [x] rows, data has [y]

TL;DR ...and late to the party, but that short explanation might help future googlers..

In general that error message means that the replacement doesn't fit into the corresponding column of the dataframe.

A minimal example:

df <- data.frame(a = 1:2); df$a <- 1:3

throws the error

Error in $<-.data.frame(*tmp*, a, value = 1:3) : replacement has 3 rows, data has 2

which is clear, because the vector a of df has 2 entries (rows) whilst the vector we try to replace it has 3 entries (rows).

Is there a code obfuscator for PHP?

I'm not sure you can label obfuscation of an interpreted language as pointless (I'm unable to add a comment to Schwern's post, so here goes a new entry).

I think it's a little shortsighted to assume you know all the possible scenarios where someone would like to obfuscate code, and you assume that anyone will actually be willing to go to whatever necessary lengths to view that code once obfuscated. Consider my current scenario:

I work for a consulting company that is developing a large and fairly sophisticated PHP-based site. The project will be hosted on a client's server that is hosting other sites developed by other consultancies. Technically any code we write is owned by the client, so we can't license it. However, any other consultancy (competitor) with access to the server can copy our code without getting permission from the client first. We therefore have a genuine reason for obfuscation - to make the effort required for a competitor to understand our code more than the effort of creating a copy of our work from scratch.

How to do a SQL NOT NULL with a DateTime?

SELECT * FROM Table where codtable not in (Select codtable from Table where fecha is null)

Python for and if on one line

Found this one:

[x for (i,x) in enumerate(my_list) if my_list[i] == "two"]

Will print:

["two"]

How can I do an OrderBy with a dynamic string parameter?

If you are using plain LINQ-to-objects and don't want to take a dependency on an external library it is not hard to achieve what you want.

The OrderBy() clause accepts a Func<TSource, TKey> that gets a sort key from a source element. You can define the function outside the OrderBy() clause:

Func<Item, Object> orderByFunc = null;

You can then assign it to different values depending on the sort criteria:

if (sortOrder == SortOrder.SortByName)
  orderByFunc = item => item.Name;
else if (sortOrder == SortOrder.SortByRank)
  orderByFunc = item => item.Rank;

Then you can sort:

var sortedItems = items.OrderBy(orderByFunc);

This example assumes that the source type is Item that have properties Name and Rank.

Note that in this example TKey is Object to not constrain the property types that can be sorted on. If the func returns a value type (like Int32) it will get boxed when sorting and that is somewhat inefficient. If you can constrain TKey to a specific value type you can work around this problem.

NavigationBar bar, tint, and title text color in iOS 8

To do this job in storyboard (Interface Builder Inspector)

With help of IBDesignable, we can add more options to Interface Builder Inspector for UINavigationController and tweak them on storyboard. First, add the following code to your project.

@IBDesignable extension UINavigationController {
    @IBInspectable var barTintColor: UIColor? {
        set {
            navigationBar.barTintColor = newValue
        }
        get {
            guard  let color = navigationBar.barTintColor else { return nil }
            return color
        }
    }

    @IBInspectable var tintColor: UIColor? {
        set {
            navigationBar.tintColor = newValue
        }
        get {
            guard  let color = navigationBar.tintColor else { return nil }
            return color
        }
    }

    @IBInspectable var titleColor: UIColor? {
        set {
            guard let color = newValue else { return }
            navigationBar.titleTextAttributes = [NSForegroundColorAttributeName: color]
        }
        get {
            return navigationBar.titleTextAttributes?["NSForegroundColorAttributeName"] as? UIColor
        }
    }
}

Then simply set the attributes for UINavigationController on storyboard.

enter image description here

Installing PIL (Python Imaging Library) in Win7 64 bits, Python 2.6.4

I think I had a similar problem in the past, with another python library. I believe that it was a windows permission issue. Try adding "Users" to your python directory, and give them full access.

How can I read Chrome Cache files?

EDIT: The below answer no longer works see here


In Chrome or Opera, open a new tab and navigate to chrome://view-http-cache/

Click on whichever file you want to view. You should then see a page with a bunch of text and numbers. Copy all the text on that page. Paste it in the text box below.

Press "Go". The cached data will appear in the Results section below.

How to add/subtract time (hours, minutes, etc.) from a Pandas DataFrame.Index whos objects are of type datetime.time?

This one worked for me:

>> print(df)
                          TotalVolume  Symbol
2016-04-15 09:00:00       108400       2802.T
2016-04-15 09:05:00       50300        2802.T

>> print(df.set_index(pd.to_datetime(df.index.values) - datetime(2016, 4, 15)))

             TotalVolume  Symbol
09:00:00     108400       2802.T
09:05:00     50300        2802.T

HttpClient 4.0.1 - how to release connection?

I've got this problem when I use HttpClient in Multithread envirnoment (Servlets). One servlet still holds connection and another one want to get connection.

Solution:

version 4.0 use ThreadSafeClientConnManager

version 4.2 use PoolingClientConnectionManager

and set this two setters:

setDefaultMaxPerRoute
setMaxTotal

zsh compinit: insecure directories

On macOS Sierra you need to run: sudo chown -R $(whoami):staff /usr/local

Check whether values in one data frame column exist in a second data frame

Use %in% as follows

A$C %in% B$C

Which will tell you which values of column C of A are in B.

What is returned is a logical vector. In the specific case of your example, you get:

A$C %in% B$C
# [1]  TRUE FALSE  TRUE  TRUE

Which you can use as an index to the rows of A or as an index to A$C to get the actual values:

# as a row index
A[A$C %in% B$C,  ]  # note the comma to indicate we are indexing rows

# as an index to A$C
A$C[A$C %in% B$C]
[1] 1 3 4  # returns all values of A$C that are in B$C

We can negate it too:

A$C[!A$C %in% B$C]
[1] 2   # returns all values of A$C that are NOT in B$C



If you want to know if a specific value is in B$C, use the same function:

  2 %in% B$C   # "is the value 2 in B$C ?"  
  # FALSE

  A$C[2] %in% B$C  # "is the 2nd element of A$C in B$C ?"  
  # FALSE

How to set proper codeigniter base url?

Base URL should be absolute, including the protocol:

$config['base_url'] = "http://somesite.com/somedir/";

If using the URL helper, then base_url() will output the above string.

Passing arguments to base_url() or site_url() will result in the following (assuming $config['index_page'] = "index.php";:

echo base_url('assets/stylesheet.css'); // http://somesite.com/somedir/assets/stylesheet.css
echo site_url('mycontroller/mymethod'); // http://somesite.com/somedir/index.php/mycontroller/mymethod

Register .NET Framework 4.5 in IIS 7.5

Hosting asp.net 4.5/4.5.1 Web application on Local IIS 1)Be Sure IIS Installation before Visual Installation Installataion then aspnet_regiis will already registerd with IIS

If Not Install IIS and then Register aspnet_regiis with IIS by cmd Editor

For VS2012 and 32 bit OS Run Below code on command editor :

1)Install IIS First & then

2)

cd C:\Windows\Microsoft.NET\Framework\v4.0.30319   

  C:\Windows\Microsoft.NET\Framework\v4.0.30319> aspnet_regiis -i

For VS2012 and 64 bit OS Below code on command editor:

1)Install IIS First & then

2)

cd C:\Windows\Microsoft.NET\Framework64\v4.0.30319    
  C:\Windows\Microsoft.NET\Framework64\v4.0.30319> aspnet_regiis -i

BY Following Above Steps Current Version of VS2012 registered with IIS Hosting (VS2012 Web APP)

Create VS2012 Web Application(WebForm/MVC) then Build Application Right Click On WebApplication(WebForm/MVC) go to 'Properties' Click On 'Web' Tab on then 'Use Local IIS Web Server' Then Uncheck 'Use IIS Express' (If Visul Studio 2013 Select 'Local IIS' from Dropdown) Provide Project Url like "http://localhost/MvcDemoApp" Then Click On 'Create Virtual Directory' Button Then Open IIS by Prssing 'Window + R' Run Command and type 'inetmgr' and 'Enter' (or 'OK' Button) Then Expand 'Sites->Default Web Site' you Hosted Successfully. If Still Gets any Server Error like 'The resource cannot be found.' Then Include following code in web.config

 <configuration>
     <system.webServer>
         <modules runAllManagedModulesForAllRequests="true"></modules>

And Run Application

If still problem occurs Check application pool by : In iis Right click on application->Manage Application->Advanced setting->General. you see the application pool. then close advance setting window. click on 'Application Pools' you will see the all application pools in middle window. Right click on application pool in which application hosted(DefaultAppPool). click 'Basic Setting' -> Change .Net FrameWork Version to->.Net FrameWork v4.0.30349

How to check if the user can go back in browser history or not

I'm not sure if this works and it is completely untested, but try this:

<script type="text/javascript">

    function goBack() {
        history.back();
    }

    if (history.length > 0) { //if there is a history...
        document.getElementsByTagName('button')[].onclick="goBack()"; //assign function "goBack()" to all buttons onClick
    } else {
        die();
    }
</script>

And somewhere in HTML:

<button value="Button1"> //These buttons have no action
<button value="Button2">

EDIT:

What you can also do is to research what browsers support the back function (I think they all do) and use the standard JavaScript browser detection object found, and described thoroughly, on this page. Then you can have 2 different pages: one for the "good browsers" compatible with the back button and one for the "bad browsers" telling them to go update their browser

Execute an action when an item on the combobox is selected

The simple solution would be to use a ItemListener. When the state changes, you would simply check the currently selected item and set the text accordingly

import java.awt.BorderLayout;
import java.awt.EventQueue;
import java.awt.event.ItemEvent;
import java.awt.event.ItemListener;
import javax.swing.JComboBox;
import javax.swing.JFrame;
import javax.swing.JPanel;
import javax.swing.JTextField;
import javax.swing.UIManager;
import javax.swing.UnsupportedLookAndFeelException;

public class TestComboBox06 {

    public static void main(String[] args) {
        new TestComboBox06();
    }

    public TestComboBox06() {
        EventQueue.invokeLater(new Runnable() {
            @Override
            public void run() {
                try {
                    UIManager.setLookAndFeel(UIManager.getSystemLookAndFeelClassName());
                } catch (ClassNotFoundException ex) {
                } catch (InstantiationException ex) {
                } catch (IllegalAccessException ex) {
                } catch (UnsupportedLookAndFeelException ex) {
                }

                JFrame frame = new JFrame("Test");
                frame.setDefaultCloseOperation(JFrame.EXIT_ON_CLOSE);
                frame.setLayout(new BorderLayout());
                frame.add(new TestPane());
                frame.pack();
                frame.setLocationRelativeTo(null);
                frame.setVisible(true);
            }

        });
    }

    public class TestPane extends JPanel {

        private JComboBox cb;
        private JTextField field;

        public TestPane() {
            cb = new JComboBox(new String[]{"Item 1", "Item 2"});
            field = new JTextField(12);

            add(cb);
            add(field);

            cb.setSelectedItem(null);

            cb.addItemListener(new ItemListener() {
                @Override
                public void itemStateChanged(ItemEvent e) {
                    Object item = cb.getSelectedItem();
                    if ("Item 1".equals(item)) {
                        field.setText("20");
                    } else if ("Item 2".equals(item)) {
                        field.setText("30");
                    }
                }
            });
        }

    }

}

A better solution would be to create a custom object that represents the value to be displayed and the value associated with it...

Updated

Now I no longer have a 10 month chewing on my ankles, I updated the example to use a ListCellRenderer which is a more correct approach then been lazy and overriding toString

import java.awt.BorderLayout;
import java.awt.Component;
import java.awt.EventQueue;
import java.awt.event.ItemEvent;
import java.awt.event.ItemListener;
import javax.swing.DefaultListCellRenderer;
import javax.swing.JComboBox;
import javax.swing.JFrame;
import javax.swing.JList;
import javax.swing.JPanel;
import javax.swing.JTextField;
import javax.swing.UIManager;
import javax.swing.UnsupportedLookAndFeelException;

public class TestComboBox06 {

    public static void main(String[] args) {
        new TestComboBox06();
    }

    public TestComboBox06() {
        EventQueue.invokeLater(new Runnable() {
            @Override
            public void run() {
                try {
                    UIManager.setLookAndFeel(UIManager.getSystemLookAndFeelClassName());
                } catch (ClassNotFoundException ex) {
                } catch (InstantiationException ex) {
                } catch (IllegalAccessException ex) {
                } catch (UnsupportedLookAndFeelException ex) {
                }

                JFrame frame = new JFrame("Test");
                frame.setDefaultCloseOperation(JFrame.EXIT_ON_CLOSE);
                frame.setLayout(new BorderLayout());
                frame.add(new TestPane());
                frame.pack();
                frame.setLocationRelativeTo(null);
                frame.setVisible(true);
            }

        });
    }

    public class TestPane extends JPanel {

        private JComboBox cb;
        private JTextField field;

        public TestPane() {
            cb = new JComboBox(new Item[]{
                new Item("Item 1", "20"), 
                new Item("Item 2", "30")});
            cb.setRenderer(new ItemCelLRenderer());
            field = new JTextField(12);

            add(cb);
            add(field);

            cb.setSelectedItem(null);

            cb.addItemListener(new ItemListener() {
                @Override
                public void itemStateChanged(ItemEvent e) {
                    Item item = (Item)cb.getSelectedItem();
                    field.setText(item.getValue());
                }
            });
        }

    }

    public class Item {
        private String value;
        private String text;

        public Item(String text, String value) {
            this.text = text;
            this.value = value;
        }

        public String getText() {
            return text;
        }

        public String getValue() {
            return value;
        }

    }

    public class ItemCelLRenderer extends DefaultListCellRenderer {

        @Override
        public Component getListCellRendererComponent(JList<?> list, Object value, int index, boolean isSelected, boolean cellHasFocus) {
            super.getListCellRendererComponent(list, value, index, isSelected, cellHasFocus); //To change body of generated methods, choose Tools | Templates.
            if (value instanceof Item) {
                setText(((Item)value).getText());
            }
            return this;
        }

    }

}

How to execute an oracle stored procedure?

Both 'is' and 'as' are valid syntax. Output is disabled by default. Try a procedure that also enables output...

create or replace procedure temp_proc is
begin
  DBMS_OUTPUT.ENABLE(1000000);
  DBMS_OUTPUT.PUT_LINE('Test');
end;

...and call it in a PLSQL block...

begin
  temp_proc;
end;

...as SQL is non-procedural.

Google Text-To-Speech API

As of now, Google official Text-to-Speech service is available at https://cloud.google.com/text-to-speech/

It's free for the first 4 million characters.

How to determine if .NET Core is installed

Run this command

dotnet --list-sdks

enter image description here

What is the best way to do a substring in a batch file?

Well, for just getting the filename of your batch the easiest way would be to just use %~n0.

@echo %~n0

will output the name (without the extension) of the currently running batch file (unless executed in a subroutine called by call). The complete list of such “special” substitutions for path names can be found with help for, at the very end of the help:

In addition, substitution of FOR variable references has been enhanced. You can now use the following optional syntax:

%~I         - expands %I removing any surrounding quotes (")
%~fI        - expands %I to a fully qualified path name
%~dI        - expands %I to a drive letter only
%~pI        - expands %I to a path only
%~nI        - expands %I to a file name only
%~xI        - expands %I to a file extension only
%~sI        - expanded path contains short names only
%~aI        - expands %I to file attributes of file
%~tI        - expands %I to date/time of file
%~zI        - expands %I to size of file
%~$PATH:I   - searches the directories listed in the PATH
               environment variable and expands %I to the
               fully qualified name of the first one found.
               If the environment variable name is not
               defined or the file is not found by the
               search, then this modifier expands to the
               empty string

The modifiers can be combined to get compound results:

%~dpI       - expands %I to a drive letter and path only
%~nxI       - expands %I to a file name and extension only
%~fsI       - expands %I to a full path name with short names only

To precisely answer your question, however: Substrings are done using the :~start,length notation:

%var:~10,5%

will extract 5 characters from position 10 in the environment variable %var%.

NOTE: The index of the strings is zero based, so the first character is at position 0, the second at 1, etc.

To get substrings of argument variables such as %0, %1, etc. you have to assign them to a normal environment variable using set first:

:: Does not work:
@echo %1:~10,5

:: Assign argument to local variable first:
set var=%1
@echo %var:~10,5%

The syntax is even more powerful:

  • %var:~-7% extracts the last 7 characters from %var%
  • %var:~0,-4% would extract all characters except the last four which would also rid you of the file extension (assuming three characters after the period [.]).

See help set for details on that syntax.

How to detect DataGridView CheckBox event change?

In the event CellContentClick you can use this strategy:

private void myDataGrid_CellContentClick(object sender, DataGridViewCellEventArgs e)
{    
    if (e.ColumnIndex == 2)//set your checkbox column index instead of 2
    {   //When you check
        if (Convert.ToBoolean(myDataGrid.Rows[e.RowIndex].Cells[2].EditedFormattedValue) == true)
        {
            //EXAMPLE OF OTHER CODE
            myDataGrid.Rows[e.RowIndex].Cells[5].Value = DateTime.Now.ToShortDateString();

            //SET BY CODE THE CHECK BOX
            myDataGrid.Rows[e.RowIndex].Cells[2].Value = 1;
        }
        else //When you decheck
        {
            myDataGrid.Rows[e.RowIndex].Cells[5].Value = String.Empty;

            //SET BY CODE THE CHECK BOX
            myDataGrid.Rows[e.RowIndex].Cells[2].Value = 0;
        }
    }
}

what is Array.any? for javascript

Array has a length property :

[].length // 0
[0].length // 1
[4, 8, 15, 16, 23, 42].length // 6

How do I "shake" an Android device within the Android emulator to bring up the dev menu to debug my React Native app

As while developing react native apps, we play with the terminal so much

so I added a script in the scripts in the package.json file

"menu": "adb shell input keyevent 82"

and I hit $ yarn menu

for the menu to appear on the emulator it will forward the keycode 82 to the emulator via ADB not the optimal way but I like it and felt to share it.

enter image description here

Copy tables from one database to another in SQL Server

If there is existing table and we wants to copy only data, we can try this query.

insert into Destination_Existing_Tbl select col1,col2 FROM Source_Tbl

Merge PDF files

A slight variation using a dictionary for greater flexibility (e.g. sort, dedup):

import os
from PyPDF2 import PdfFileMerger
# use dict to sort by filepath or filename
file_dict = {}
for subdir, dirs, files in os.walk("<dir>"):
    for file in files:
        filepath = subdir + os.sep + file
        # you can have multiple endswith
        if filepath.endswith((".pdf", ".PDF")):
            file_dict[file] = filepath
# use strict = False to ignore PdfReadError: Illegal character error
merger = PdfFileMerger(strict=False)

for k, v in file_dict.items():
    print(k, v)
    merger.append(v)

merger.write("combined_result.pdf")

Preprocessing in scikit learn - single sample - Depreciation warning

I faced the same issue and got the same deprecation warning. I was using a numpy array of [23, 276] when I got the message. I tried reshaping it as per the warning and end up in nowhere. Then I select each row from the numpy array (as I was iterating over it anyway) and assigned it to a list variable. It worked then without any warning.

array = []
array.append(temp[0])

Then you can use the python list object (here 'array') as an input to sk-learn functions. Not the most efficient solution, but worked for me.

How to check if keras tensorflow backend is GPU or CPU version?

According to the documentation.

If you are running on the TensorFlow or CNTK backends, your code will automatically run on GPU if any available GPU is detected.

You can check what all devices are used by tensorflow by -

from tensorflow.python.client import device_lib
print(device_lib.list_local_devices())

Also as suggested in this answer

import tensorflow as tf
sess = tf.Session(config=tf.ConfigProto(log_device_placement=True))

This will print whether your tensorflow is using a CPU or a GPU backend. If you are running this command in jupyter notebook, check out the console from where you have launched the notebook.

If you are sceptic whether you have installed the tensorflow gpu version or not. You can install the gpu version via pip.

pip install tensorflow-gpu

javax.net.ssl.SSLHandshakeException: Remote host closed connection during handshake during web service communicaiton

This is what solve my problem.

If you are trying to use debugger make sure you breakpoint is not on URL or URLConnection just put your breakpoint on BufferReader or inside while loop.

If nothing works try using apache library http://hc.apache.org/index.html.

no SSL, no JDK update needed, no need to set properties even, just simple trick :)

Changing file permission in Python

FYI here is a function to convert a permission string with 9 characters (e.g. 'rwsr-x-wt') to a mask that can be used with os.chmod().

def perm2mask(p):
        
    assert len(p) == 9, 'Bad permission length'
    assert all(p[k] in 'rw-' for k in [0,1,3,4,6,7]), 'Bad permission format (read-write)'
    assert all(p[k] in 'xs-' for k in [2,5]), 'Bad permission format (execute)'
    assert p[8] in 'xt-', 'Bad permission format (execute other)'
    
    m = 0
    
    if p[0] == 'r': m |= stat.S_IRUSR 
    if p[1] == 'w': m |= stat.S_IWUSR 
    if p[2] == 'x': m |= stat.S_IXUSR 
    if p[2] == 's': m |= stat.S_IXUSR | stat.S_ISUID 
    
    if p[3] == 'r': m |= stat.S_IRGRP 
    if p[4] == 'w': m |= stat.S_IWGRP 
    if p[5] == 'x': m |= stat.S_IXGRP 
    if p[5] == 's': m |= stat.S_IXGRP | stat.S_ISGID 
    
    if p[6] == 'r': m |= stat.S_IROTH 
    if p[7] == 'w': m |= stat.S_IWOTH 
    if p[8] == 'x': m |= stat.S_IXOTH 
    if p[8] == 't': m |= stat.S_IXOTH | stat.S_ISVTX
    
    return m

Note that setting SUID/SGID/SVTX bits will automatically set the corresponding execute bit. Without this, the resulting permission would be invalid (ST characters).

How to add new column to MYSQL table?

You should look into normalizing your database to avoid creating columns at runtime.

Make 3 tables:

  1. assessment
  2. question
  3. assessment_question (columns assessmentId, questionId)

Put questions and assessments in their respective tables and link them together through assessment_question using foreign keys.

How to implement an android:background that doesn't stretch?

I had a background image, not big in size, but with weird dimensions - therefore the stretching and bad performance. I made a method with parameters Context, a View and a drawable ID(int) that will match the device screen size. Use this in e.g a Fragments onCreateView to set the background.

public void setBackground(Context context, View view, int drawableId){
    Bitmap bitmap = BitmapFactory.decodeResource(context.getResources(),drawableId);

    bitmap = Bitmap.createScaledBitmap(bitmap, Resources.getSystem().
             getDisplayMetrics().widthPixels,
             Resources.getSystem().getDisplayMetrics().heightPixels,
             true);

    BitmapDrawable bitmapDrawable = new BitmapDrawable(context.getResources(), 
                                    bitmap);

    view.setBackground(bitmapDrawable);
}

Can not deserialize instance of java.lang.String out of START_OBJECT token

You're mapping this JSON

{
    "id": 2,
    "socket": "0c317829-69bf-43d6-b598-7c0c550635bb",
    "type": "getDashboard",
    "data": {
        "workstationUuid": "ddec1caa-a97f-4922-833f-632da07ffc11"
    },
    "reply": true
}

that contains an element named data that has a JSON object as its value. You are trying to deserialize the element named workstationUuid from that JSON object into this setter.

@JsonProperty("workstationUuid")
public void setWorkstation(String workstationUUID) {

This won't work directly because Jackson sees a JSON_OBJECT, not a String.

Try creating a class Data

public class Data { // the name doesn't matter 
    @JsonProperty("workstationUuid")
    private String workstationUuid;
    // getter and setter
}

the switch up your method

@JsonProperty("data")
public void setWorkstation(Data data) {
    // use getter to retrieve it

How do I do redo (i.e. "undo undo") in Vim?

CTRL+r

The "r" is lower-case.

Creating a new ArrayList in Java

Do this: List<Class> myArray= new ArrayList<Class>();

Slicing a dictionary

You should be iterating over the tuple and checking if the key is in the dict not the other way around, if you don't check if the key exists and it is not in the dict you are going to get a key error:

print({k:d[k] for k in l if k in d})

Some timings:

 {k:d[k] for k in set(d).intersection(l)}

In [22]: %%timeit                        
l = xrange(100000)
{k:d[k] for k in l}
   ....: 
100 loops, best of 3: 11.5 ms per loop

In [23]: %%timeit                        
l = xrange(100000)
{k:d[k] for k in set(d).intersection(l)}
   ....: 
10 loops, best of 3: 20.4 ms per loop

In [24]: %%timeit                        
l = xrange(100000)
l = set(l)                              
{key: d[key] for key in d.viewkeys() & l}
   ....: 
10 loops, best of 3: 24.7 ms per

In [25]: %%timeit                        

l = xrange(100000)
{k:d[k] for k in l if k in d}
   ....: 
100 loops, best of 3: 17.9 ms per loop

I don't see how {k:d[k] for k in l} is not readable or elegant and if all elements are in d then it is pretty efficient.

Unable to import path from django.urls

As error shows that path can not be imported.

enter image description here

So here we will use the url instead of path as shown below:-

first import the url package then replace the path with url

from django.conf.urls import url
urlpatterns = [
    url('admin/', admin.site.urls),
]

for more information you can take the reference of this link.

Calculating average of an array list?

sum += i;

You're adding the index; you should be adding the actual item in the ArrayList:

sum += marks.get(i);

Also, to ensure the return value isn't truncated, force one operand to double and change your method signature to double:

return (double)sum / marks.size();

Password Strength Meter

Password Strength Algorithm:

Password Length:
    5 Points: Less than 4 characters
    10 Points: 5 to 7 characters
    25 Points: 8 or more

Letters:
    0 Points: No letters
    10 Points: Letters are all lower case
    20 Points: Letters are upper case and lower case

Numbers:
    0 Points: No numbers
    10 Points: 1 number
    20 Points: 3 or more numbers

Characters:
    0 Points: No characters
    10 Points: 1 character
    25 Points: More than 1 character

Bonus:
    2 Points: Letters and numbers
    3 Points: Letters, numbers, and characters
    5 Points: Mixed case letters, numbers, and characters

Password Text Range:

    >= 90: Very Secure
    >= 80: Secure
    >= 70: Very Strong
    >= 60: Strong
    >= 50: Average
    >= 25: Weak
    >= 0: Very Weak

Settings Toggle to true or false, if you want to change what is checked in the password

var m_strUpperCase = "ABCDEFGHIJKLMNOPQRSTUVWXYZ";
var m_strLowerCase = "abcdefghijklmnopqrstuvwxyz";
var m_strNumber = "0123456789";
var m_strCharacters = "!@#$%^&*?_~"

Check password


function checkPassword(strPassword)
{
    // Reset combination count
    var nScore = 0;

    // Password length
    // -- Less than 4 characters
    if (strPassword.length < 5)
    {
        nScore += 5;
    }
    // -- 5 to 7 characters
    else if (strPassword.length > 4 && strPassword.length < 8)
    {
        nScore += 10;
    }
    // -- 8 or more
    else if (strPassword.length > 7)
    {
        nScore += 25;
    }

    // Letters
    var nUpperCount = countContain(strPassword, m_strUpperCase);
    var nLowerCount = countContain(strPassword, m_strLowerCase);
    var nLowerUpperCount = nUpperCount + nLowerCount;
    // -- Letters are all lower case
    if (nUpperCount == 0 && nLowerCount != 0) 
    { 
        nScore += 10; 
    }
    // -- Letters are upper case and lower case
    else if (nUpperCount != 0 && nLowerCount != 0) 
    { 
        nScore += 20; 
    }

    // Numbers
    var nNumberCount = countContain(strPassword, m_strNumber);
    // -- 1 number
    if (nNumberCount == 1)
    {
        nScore += 10;
    }
    // -- 3 or more numbers
    if (nNumberCount >= 3)
    {
        nScore += 20;
    }

    // Characters
    var nCharacterCount = countContain(strPassword, m_strCharacters);
    // -- 1 character
    if (nCharacterCount == 1)
    {
        nScore += 10;
    }   
    // -- More than 1 character
    if (nCharacterCount > 1)
    {
        nScore += 25;
    }

    // Bonus
    // -- Letters and numbers
    if (nNumberCount != 0 && nLowerUpperCount != 0)
    {
        nScore += 2;
    }
    // -- Letters, numbers, and characters
    if (nNumberCount != 0 && nLowerUpperCount != 0 && nCharacterCount != 0)
    {
        nScore += 3;
    }
    // -- Mixed case letters, numbers, and characters
    if (nNumberCount != 0 && nUpperCount != 0 && nLowerCount != 0 && nCharacterCount != 0)
    {
        nScore += 5;
    }


    return nScore;
}

// Runs password through check and then updates GUI 


function runPassword(strPassword, strFieldID) 
{
    // Check password
    var nScore = checkPassword(strPassword);


     // Get controls
        var ctlBar = document.getElementById(strFieldID + "_bar"); 
        var ctlText = document.getElementById(strFieldID + "_text");
        if (!ctlBar || !ctlText)
            return;

        // Set new width
        ctlBar.style.width = (nScore*1.25>100)?100:nScore*1.25 + "%";

    // Color and text
    // -- Very Secure
    /*if (nScore >= 90)
    {
        var strText = "Very Secure";
        var strColor = "#0ca908";
    }
    // -- Secure
    else if (nScore >= 80)
    {
        var strText = "Secure";
        vstrColor = "#7ff67c";
    }
    // -- Very Strong
    else 
    */
    if (nScore >= 80)
    {
        var strText = "Very Strong";
        var strColor = "#008000";
    }
    // -- Strong
    else if (nScore >= 60)
    {
        var strText = "Strong";
        var strColor = "#006000";
    }
    // -- Average
    else if (nScore >= 40)
    {
        var strText = "Average";
        var strColor = "#e3cb00";
    }
    // -- Weak
    else if (nScore >= 20)
    {
        var strText = "Weak";
        var strColor = "#Fe3d1a";
    }
    // -- Very Weak
    else
    {
        var strText = "Very Weak";
        var strColor = "#e71a1a";
    }

    if(strPassword.length == 0)
    {
    ctlBar.style.backgroundColor = "";
    ctlText.innerHTML =  "";
    }
else
    {
    ctlBar.style.backgroundColor = strColor;
    ctlText.innerHTML =  strText;
}
}

// Checks a string for a list of characters
function countContain(strPassword, strCheck)
{ 
    // Declare variables
    var nCount = 0;

    for (i = 0; i < strPassword.length; i++) 
    {
        if (strCheck.indexOf(strPassword.charAt(i)) > -1) 
        { 
                nCount++;
        } 
    } 

    return nCount; 
} 

You can customize by yourself according to your requirement.

How to add include and lib paths to configure/make cycle?

Set LDFLAGS and CFLAGS when you run make:

$ LDFLAGS="-L/home/me/local/lib" CFLAGS="-I/home/me/local/include" make

If you don't want to do that a gazillion times, export these in your .bashrc (or your shell equivalent). Also set LD_LIBRARY_PATH to include /home/me/local/lib:

export LD_LIBRARY_PATH=$LD_LIBRARY_PATH:/home/me/local/lib

Classpath including JAR within a JAR

You need to build a custom class-loader to do this or a third-party library that supports this. Your best bet is to extract the jar from the runtime and add them to the classpath (or have them already added to the classpath).

Creating JSON on the fly with JObject

You can use the JObject.Parse operation and simply supply single quote delimited JSON text.

JObject  o = JObject.Parse(@"{
  'CPU': 'Intel',
  'Drives': [
    'DVD read/writer',
    '500 gigabyte hard drive'
  ]
}");

This has the nice benefit of actually being JSON and so it reads as JSON.

Or you have test data that is dynamic you can use JObject.FromObject operation and supply a inline object.

JObject o = JObject.FromObject(new
{
    channel = new
    {
        title = "James Newton-King",
        link = "http://james.newtonking.com",
        description = "James Newton-King's blog.",
        item =
            from p in posts
            orderby p.Title
            select new
            {
                title = p.Title,
                description = p.Description,
                link = p.Link,
                category = p.Categories
            }
    }
});

Json.net documentation for serialization

an htop-like tool to display disk activity in linux

You could use iotop. It doesn't rely on a kernel patch. It Works with stock Ubuntu kernel

There is a package for it in the Ubuntu repos. You can install it using

sudo apt-get install iotop

iotop

Jquery asp.net Button Click Event via ajax

I found myself wanting to do this and I reviewed the above answers and did a hybrid approach of them. It got a little tricky, but here is what I did:

My button already worked with a server side post. I wanted to let that to continue to work so I left the "OnClick" the same, but added a OnClientClick:

OnClientClick="if (!OnClick_Submit()) return false;"

Here is my full button element in case it matters:

<asp:Button UseSubmitBehavior="false" runat="server" Class="ms-ButtonHeightWidth jiveSiteSettingsSubmit" OnClientClick="if (!OnClick_Submit()) return false;" OnClick="BtnSave_Click" Text="<%$Resources:wss,multipages_okbutton_text%>" id="BtnOK" accesskey="<%$Resources:wss,okbutton_accesskey%>" Enabled="true"/>

If I inspect the onclick attribute of the HTML button at runtime it actually looks like this:

if (!OnClick_Submit()) return false;WebForm_DoPostBackWithOptions(new WebForm_PostBackOptions("ctl00$PlaceHolderMain$ctl03$RptControls$BtnOK", "", true, "", "", false, true))

Then in my Javascript I added the OnClick_Submit method. In my case I needed to do a check to see if I needed to show a dialog to the user. If I show the dialog I return false causing the event to stop processing. If I don't show the dialog I return true causing the event to continue processing and my postback logic to run as it used to.

function OnClick_Submit() {
    var initiallyActive = initialState.socialized && initialState.activityEnabled;
    var socialized = IsSocialized();
    var enabled = ActivityStreamsEnabled();

    var displayDialog;

    // Omitted the setting of displayDialog for clarity

    if (displayDialog) {
        $("#myDialog").dialog('open');
        return false;
    }
    else {
        return true;
    }
}

Then in my Javascript code that runs when the dialog is accepted, I do the following depending on how the user interacted with the dialog:

$("#myDialog").dialog('close');
__doPostBack('message', '');

The "message" above is actually different based on what message I want to send.

But wait, there's more!

Back in my server-side code, I changed OnLoad from:

protected override void OnLoad(EventArgs e)
{
    base.OnLoad(e)
    if (IsPostBack)
    {
        return;
    }

    // OnLoad logic removed for clarity
}

To:

protected override void OnLoad(EventArgs e)
{
    base.OnLoad(e)
    if (IsPostBack)
    {
        switch (Request.Form["__EVENTTARGET"])
        {
            case "message1":
                // We did a __doPostBack with the "message1" command provided
                Page.Validate();
                BtnSave_Click(this, new CommandEventArgs("message1", null));
                break;

            case "message2":
                // We did a __doPostBack with the "message2" command provided
                Page.Validate();
                BtnSave_Click(this, new CommandEventArgs("message2", null));
                break;
            }
            return;
    }

    // OnLoad logic removed for clarity
}

Then in BtnSave_Click method I do the following:

CommandEventArgs commandEventArgs = e as CommandEventArgs;
string message = (commandEventArgs == null) ? null : commandEventArgs.CommandName;

And finally I can provide logic based on whether or not I have a message and based on the value of that message.

How to reverse apply a stash?

git stash show -p | git apply --reverse

Warning, that would not in every case: "git apply -R"(man) did not handle patches that touch the same path twice correctly, which has been corrected with Git 2.30 (Q1 2021).

This is most relevant in a patch that changes a path from a regular file to a symbolic link (and vice versa).

See commit b0f266d (20 Oct 2020) by Jonathan Tan (jhowtan).
(Merged by Junio C Hamano -- gitster -- in commit c23cd78, 02 Nov 2020)

apply: when -R, also reverse list of sections

Helped-by: Junio C Hamano
Signed-off-by: Jonathan Tan

A patch changing a symlink into a file is written with 2 sections (in the code, represented as "struct patch"): firstly, the deletion of the symlink, and secondly, the creation of the file.

When applying that patch with -R, the sections are reversed, so we get: (1) creation of a symlink, then (2) deletion of a file.

This causes an issue when the "deletion of a file" section is checked, because Git observes that the so-called file is not a file but a symlink, resulting in a "wrong type" error message.

What we want is: (1) deletion of a file, then (2) creation of a symlink.

In the code, this is reflected in the behavior of previous_patch() when invoked from check_preimage() when the deletion is checked.
Creation then deletion means that when the deletion is checked, previous_patch() returns the creation section, triggering a mode conflict resulting in the "wrong type" error message.

But deletion then creation means that when the deletion is checked, previous_patch() returns NULL, so the deletion mode is checked against lstat, which is what we want.

There are also other ways a patch can contain 2 sections referencing the same file, for example, in 7a07841c0b ("git-apply: handle a patch that touches the same path more than once better", 2008-06-27, Git v1.6.0-rc0 -- merge). "git apply -R"(man) fails in the same way, and this commit makes this case succeed.

Therefore, when building the list of sections, build them in reverse order (by adding to the front of the list instead of the back) when -R is passed.

Forcing anti-aliasing using css: Is this a myth?

Not a pure CSS but natively supported method without any font replacement hacks: Simply convert your font to SVG and place it higher(before WOFF or TTF) in @font-face order. Voila! Fonts are smooth now, because they're no longer treated as a font but an SVG shape which will be nicely smoothened.

Note: I noticed that SVG can weight more than WOFF or TTF.

I want to get the type of a variable at runtime

If by the type of a variable you mean the runtime class of the object that the variable points to, then you can get this through the class reference that all objects have.

val name = "sam";
name: java.lang.String = sam
name.getClass
res0: java.lang.Class[_] = class java.lang.String

If you however mean the type that the variable was declared as, then you cannot get that. Eg, if you say

val name: Object = "sam"

then you will still get a String back from the above code.

Android studio 3.0: Unable to resolve dependency for :app@dexOptions/compileClasspath': Could not resolve project :animators

This thread seems to have wondered a bit, however as relating to the original question, not only do you have to have your buildTypes in both build.gradle files, you need to have your productFlavors (if you are using them of course) in both build.gradle files as well.

How do you cast a List of supertypes to a List of subtypes?

The problem is that your method does NOT return a list of TestA if it contains a TestB, so what if it was correctly typed? Then this cast:

class TestA{};
class TestB extends TestA{};
List<? extends TestA> listA;
List<TestB> listB = (List<TestB>) listA;

works about as well as you could hope for (Eclipse warns you of an unchecked cast which is exactly what you are doing, so meh). So can you use this to solve your problem? Actually you can because of this:

List<TestA> badlist = null; // Actually contains TestBs, as specified
List<? extends TestA> talist = badlist;  // Umm, works
List<TextB> tblist = (List<TestB>)talist; // TADA!

Exactly what you asked for, right? or to be really exact:

List<TestB> tblist = (List<TestB>)(List<? extends TestA>) badlist;

seems to compile just fine for me.

Is it possible to reference one CSS rule within another?

You can easily do so with SASS pre-processor by using @extend.

someDiv {
    @extend .opacity;
    @extend .radius;
}

Ohterwise, you could use JavaScript (jQuery) as well:

$('someDiv').addClass('opacity radius')

The easiest is of course to add multiple classes right in the HTML

<div class="opacity radius">

href image link download on click

Try this...

<a href="/path/to/image" download>
    <img src="/path/to/image" />
 </a>

Get the time of a datetime using T-SQL?

You can try the following code to get time as HH:MM format:

 SELECT CONVERT(VARCHAR(5),getdate(),108)

iOS UIImagePickerController result image orientation after upload

If you enable editing, then the edited image (as opposed to the original) will be oriented as expected:

UIImagePickerController *imagePickerController = [[UIImagePickerController alloc] init];
imagePickerController.allowsEditing = YES;
// set delegate and present controller

- (void)imagePickerController:(UIImagePickerController *)picker didFinishPickingMediaWithInfo:(NSDictionary *)info {
    UIImage *photo = [info valueForKey:UIImagePickerControllerEditedImage];
    // do whatever
}

Enabling editing allows the user to resize and move the image before tapping "Use Photo"

ActionController::InvalidAuthenticityToken

For rails 5, it better to add protect_from_forgery prepend: true than to skip the verify_authentication_token

How to execute a .bat file from a C# windows form app?

Here is what you are looking for:

Service hangs up at WaitForExit after calling batch file

It's about a question as to why a service can't execute a file, but it shows all the code necessary to do so.

Using CSS to align a button bottom of the screen using relative positions

<button style="position: absolute; left: 20%; right: 20%; bottom: 5%;"> Button </button>

Find object in list that has attribute equal to some value (that meets any condition)

Since it has not been mentioned just for completion. The good ol' filter to filter your to be filtered elements.

Functional programming ftw.

####### Set Up #######
class X:

    def __init__(self, val):
        self.val = val

elem = 5

my_unfiltered_list = [X(1), X(2), X(3), X(4), X(5), X(5), X(6)]

####### Set Up #######

### Filter one liner ### filter(lambda x: condition(x), some_list)
my_filter_iter = filter(lambda x: x.val == elem, my_unfiltered_list)
### Returns a flippin' iterator at least in Python 3.5 and that's what I'm on

print(next(my_filter_iter).val)
print(next(my_filter_iter).val)
print(next(my_filter_iter).val)

### [1, 2, 3, 4, 5, 5, 6] Will Return: ###
# 5
# 5
# Traceback (most recent call last):
#   File "C:\Users\mousavin\workspace\Scripts\test.py", line 22, in <module>
#     print(next(my_filter_iter).value)
# StopIteration


# You can do that None stuff or whatever at this point, if you don't like exceptions.

I know that generally in python list comprehensions are preferred or at least that is what I read, but I don't see the issue to be honest. Of course Python is not an FP language, but Map / Reduce / Filter are perfectly readable and are the most standard of standard use cases in functional programming.

So there you go. Know thy functional programming.

filter condition list

It won't get any easier than this:

next(filter(lambda x: x.val == value,  my_unfiltered_list)) # Optionally: next(..., None) or some other default value to prevent Exceptions

how to get docker-compose to use the latest image from repository

I've seen this occur in our 7-8 docker production system. Another solution that worked for me in production was to run

docker-compose down
docker-compose up -d

this removes the containers and seems to make 'up' create new ones from the latest image.

This doesn't yet solve my dream of down+up per EACH changed container (serially, less down time), but it works to force 'up' to update the containers.

what is numeric(18, 0) in sql server 2008 r2

The first value is the precision and the second is the scale, so 18,0 is essentially 18 digits with 0 digits after the decimal place. If you had 18,2 for example, you would have 18 digits, two of which would come after the decimal...

example of 18,2: 1234567890123456.12

There is no functional difference between numeric and decimal, other that the name and I think I recall that numeric came first, as in an earlier version.

And to answer, "can I add (-10) in that column?" - Yes, you can.

UIWebView open links in Safari

In my case I want to make sure that absolutely everything in the web view opens Safari except the initial load and so I use...

- (BOOL)webView:(UIWebView *)inWeb shouldStartLoadWithRequest:(NSURLRequest *)inRequest navigationType:(UIWebViewNavigationType)inType {
     if(inType != UIWebViewNavigationTypeOther) {
        [[UIApplication sharedApplication] openURL:[inRequest URL]];
        return NO;
     }
     return YES;
}

How to use BigInteger?

Other replies have nailed it; BigInteger is immutable. Here's the minor change to make that code work.

BigInteger sum = BigInteger.valueOf(0);
for(int i = 2; i < 5000; i++) {
    if (isPrim(i)) {
        sum = sum.add(BigInteger.valueOf(i));
    }
}

u'\ufeff' in Python string

Here is based on the answer from Mark Tolonen. The string included different languages of the word 'test' that's separated by '|', so you can see the difference.

u = u'ABCtestß???másbêta|test|??????|??|??|???|???????|???????|????????|ki?m tra|Ölçek|'
e8 = u.encode('utf-8')        # encode without BOM
e8s = u.encode('utf-8-sig')   # encode with BOM
e16 = u.encode('utf-16')      # encode with BOM
e16le = u.encode('utf-16le')  # encode without BOM
e16be = u.encode('utf-16be')  # encode without BOM
print('utf-8     %r' % e8)
print('utf-8-sig %r' % e8s)
print('utf-16    %r' % e16)
print('utf-16le  %r' % e16le)
print('utf-16be  %r' % e16be)
print()
print('utf-8  w/ BOM decoded with utf-8     %r' % e8s.decode('utf-8'))
print('utf-8  w/ BOM decoded with utf-8-sig %r' % e8s.decode('utf-8-sig'))
print('utf-16 w/ BOM decoded with utf-16    %r' % e16.decode('utf-16'))
print('utf-16 w/ BOM decoded with utf-16le  %r' % e16.decode('utf-16le'))

Here is a test run:

>>> u = u'ABCtestß???másbêta|test|??????|??|??|???|???????|???????|????????|ki?m tra|Ölçek|'
>>> e8 = u.encode('utf-8')        # encode without BOM
>>> e8s = u.encode('utf-8-sig')   # encode with BOM
>>> e16 = u.encode('utf-16')      # encode with BOM
>>> e16le = u.encode('utf-16le')  # encode without BOM
>>> e16be = u.encode('utf-16be')  # encode without BOM
>>> print('utf-8     %r' % e8)
utf-8     b'ABCtest\xce\xb2\xe8\xb2\x9d\xe5\xa1\x94\xec\x9c\x84m\xc3\xa1sb\xc3\xaata|test|\xd8\xa7\xd8\xae\xd8\xaa\xd8\xa8\xd8\xa7\xd8\xb1|\xe6\xb5\x8b\xe8\xaf\x95|\xe6\xb8\xac\xe8\xa9\xa6|\xe3\x83\x86\xe3\x82\xb9\xe3\x83\x88|\xe0\xa4\xaa\xe0\xa4\xb0\xe0\xa5\x80\xe0\xa4\x95\xe0\xa5\x8d\xe0\xa4\xb7\xe0\xa4\xbe|\xe0\xb4\xaa\xe0\xb4\xb0\xe0\xb4\xbf\xe0\xb4\xb6\xe0\xb5\x8b\xe0\xb4\xa7\xe0\xb4\xa8|\xd7\xa4\xd6\xbc\xd7\xa8\xd7\x95\xd7\x91\xd7\x99\xd7\xa8\xd7\x9f|ki\xe1\xbb\x83m tra|\xc3\x96l\xc3\xa7ek|'
>>> print('utf-8-sig %r' % e8s)
utf-8-sig b'\xef\xbb\xbfABCtest\xce\xb2\xe8\xb2\x9d\xe5\xa1\x94\xec\x9c\x84m\xc3\xa1sb\xc3\xaata|test|\xd8\xa7\xd8\xae\xd8\xaa\xd8\xa8\xd8\xa7\xd8\xb1|\xe6\xb5\x8b\xe8\xaf\x95|\xe6\xb8\xac\xe8\xa9\xa6|\xe3\x83\x86\xe3\x82\xb9\xe3\x83\x88|\xe0\xa4\xaa\xe0\xa4\xb0\xe0\xa5\x80\xe0\xa4\x95\xe0\xa5\x8d\xe0\xa4\xb7\xe0\xa4\xbe|\xe0\xb4\xaa\xe0\xb4\xb0\xe0\xb4\xbf\xe0\xb4\xb6\xe0\xb5\x8b\xe0\xb4\xa7\xe0\xb4\xa8|\xd7\xa4\xd6\xbc\xd7\xa8\xd7\x95\xd7\x91\xd7\x99\xd7\xa8\xd7\x9f|ki\xe1\xbb\x83m tra|\xc3\x96l\xc3\xa7ek|'
>>> print('utf-16    %r' % e16)
utf-16    b"\xff\xfeA\x00B\x00C\x00t\x00e\x00s\x00t\x00\xb2\x03\x9d\x8cTX\x04\xc7m\x00\xe1\x00s\x00b\x00\xea\x00t\x00a\x00|\x00t\x00e\x00s\x00t\x00|\x00'\x06.\x06*\x06(\x06'\x061\x06|\x00Km\xd5\x8b|\x00,nf\x8a|\x00\xc60\xb90\xc80|\x00*\t0\t@\t\x15\tM\t7\t>\t|\x00*\r0\r?\r6\rK\r'\r(\r|\x00\xe4\x05\xbc\x05\xe8\x05\xd5\x05\xd1\x05\xd9\x05\xe8\x05\xdf\x05|\x00k\x00i\x00\xc3\x1em\x00 \x00t\x00r\x00a\x00|\x00\xd6\x00l\x00\xe7\x00e\x00k\x00|\x00"
>>> print('utf-16le  %r' % e16le)
utf-16le  b"A\x00B\x00C\x00t\x00e\x00s\x00t\x00\xb2\x03\x9d\x8cTX\x04\xc7m\x00\xe1\x00s\x00b\x00\xea\x00t\x00a\x00|\x00t\x00e\x00s\x00t\x00|\x00'\x06.\x06*\x06(\x06'\x061\x06|\x00Km\xd5\x8b|\x00,nf\x8a|\x00\xc60\xb90\xc80|\x00*\t0\t@\t\x15\tM\t7\t>\t|\x00*\r0\r?\r6\rK\r'\r(\r|\x00\xe4\x05\xbc\x05\xe8\x05\xd5\x05\xd1\x05\xd9\x05\xe8\x05\xdf\x05|\x00k\x00i\x00\xc3\x1em\x00 \x00t\x00r\x00a\x00|\x00\xd6\x00l\x00\xe7\x00e\x00k\x00|\x00"
>>> print('utf-16be  %r' % e16be)
utf-16be  b"\x00A\x00B\x00C\x00t\x00e\x00s\x00t\x03\xb2\x8c\x9dXT\xc7\x04\x00m\x00\xe1\x00s\x00b\x00\xea\x00t\x00a\x00|\x00t\x00e\x00s\x00t\x00|\x06'\x06.\x06*\x06(\x06'\x061\x00|mK\x8b\xd5\x00|n,\x8af\x00|0\xc60\xb90\xc8\x00|\t*\t0\t@\t\x15\tM\t7\t>\x00|\r*\r0\r?\r6\rK\r'\r(\x00|\x05\xe4\x05\xbc\x05\xe8\x05\xd5\x05\xd1\x05\xd9\x05\xe8\x05\xdf\x00|\x00k\x00i\x1e\xc3\x00m\x00 \x00t\x00r\x00a\x00|\x00\xd6\x00l\x00\xe7\x00e\x00k\x00|"
>>> print()

>>> print('utf-8  w/ BOM decoded with utf-8     %r' % e8s.decode('utf-8'))
utf-8  w/ BOM decoded with utf-8     '\ufeffABCtestß???másbêta|test|??????|??|??|???|???????|???????|????????|ki?m tra|Ölçek|'
>>> print('utf-8  w/ BOM decoded with utf-8-sig %r' % e8s.decode('utf-8-sig'))
utf-8  w/ BOM decoded with utf-8-sig 'ABCtestß???másbêta|test|??????|??|??|???|???????|???????|????????|ki?m tra|Ölçek|'
>>> print('utf-16 w/ BOM decoded with utf-16    %r' % e16.decode('utf-16'))
utf-16 w/ BOM decoded with utf-16    'ABCtestß???másbêta|test|??????|??|??|???|???????|???????|????????|ki?m tra|Ölçek|'
>>> print('utf-16 w/ BOM decoded with utf-16le  %r' % e16.decode('utf-16le'))
utf-16 w/ BOM decoded with utf-16le  '\ufeffABCtestß???másbêta|test|??????|??|??|???|???????|???????|????????|ki?m tra|Ölçek|'

It's worth to know that only both utf-8-sig and utf-16 get back the original string after both encode and decode.

jQuery get value of select onChange

For all selects, invoke this function.

$('select').on('change', function()
{
    alert( this.value );
});

For only one select:

$('#select_id') 

Easiest way to convert a List to a Set in Java

Let's not forget our relatively new friend, stream API. If you need to preprocess list before converting it to a set, it's better to have something like:

list.stream().<here goes some preprocessing>.collect(Collectors.toSet());

Can't ping a local VM from the host

try to drop the firewall on your laptop and see if there is difference. Maybe Your laptop is firewall blocking some broadcasts that prevents local network name resolution.

How can I strip first X characters from string using sed?

Here's a concise method to cut the first X characters using cut(1). This example removes the first 4 characters by cutting a substring starting with 5th character.

echo "$pid" | cut -c 5-

Change color of PNG image via CSS?

Think I have a solution for this that's a) exactly what you were looking for 5 years ago, and b) is a bit simpler than the other code options here.

With any white png (eg, white icon on transparent background), you can add an ::after selector to recolor.

.icon {
    background: url(img/icon.png); /* Your icon */
    position: relative; /* Allows an absolute positioned psuedo element */
}

.icon::after{
    position: absolute; /* Positions psuedo element relative to .icon */
    width: 100%; /* Same dimensions as .icon */
    height: 100%;
    content: ""; /* Allows psuedo element to show */
    background: #EC008C; /* The color you want the icon to change to */
    mix-blend-mode: multiply; /* Only apply color on top of white, use screen if icon is black */
}

See this codepen (applying the color swap on hover): http://codepen.io/chrscblls/pen/bwAXZO

How to increase Bootstrap Modal Width?

default dialog size is 500px. If you want your dialog look large than default size than you should add class="modal-dialog modal-lg modal-dialog-centered" you can see the difference.

How to establish a connection pool in JDBC?

Pool

  • Pooling Mechanism is the way of creating the Objects in advance. When a class is loaded.
  • It improves the application performance [By re using same object's to perform any action on Object-Data] & memory [allocating and de-allocating many objects creates a significant memory management overhead].
  • Object clean-up is not required as we are using same Object, reducing the Garbage collection load.

« Pooling [ Object pool, String Constant Pool, Thread Pool, Connection pool]

String Constant pool

  • String literal pool maintains only one copy of each distinct string value. which must be immutable.
  • When the intern method is invoked, it check object availability with same content in pool using equals method. « If String-copy is available in the Pool then returns the reference. « Otherwise, String object is added to the pool and returns the reference.

Example: String to verify Unique Object from pool.

public class StringPoolTest {
    public static void main(String[] args) { // Integer.valueOf(), String.equals()
        String eol = System.getProperty("line.separator"); //java7 System.lineSeparator();

        String s1 = "Yash".intern();
        System.out.format("Val:%s Hash:%s SYS:%s "+eol, s1, s1.hashCode(), System.identityHashCode(s1));
        String s2 = "Yas"+"h".intern();
        System.out.format("Val:%s Hash:%s SYS:%s "+eol, s2, s2.hashCode(), System.identityHashCode(s2));
        String s3 = "Yas".intern()+"h".intern();
        System.out.format("Val:%s Hash:%s SYS:%s "+eol, s3, s3.hashCode(), System.identityHashCode(s3));
        String s4 = "Yas"+"h";
        System.out.format("Val:%s Hash:%s SYS:%s "+eol, s4, s4.hashCode(), System.identityHashCode(s4));
    }
}

Connection pool using Type-4 Driver using 3rd party libraries[ DBCP2, c3p0, Tomcat JDBC]

Type 4 - The Thin driver converts JDBC calls directly into the vendor-specific database protocol Ex[Oracle - Thick, MySQL - Quora]. wiki

In Connection pool mechanism, when the class is loaded it get's the physical JDBC connection objects and provides a wrapped physical connection object to user. PoolableConnection is a wrapper around the actual connection.

  • getConnection() pick one of the free wrapped-connection form the connection objectpool and returns it.
  • close() instead of closing it returns the wrapped-connection back to pool.

Example: Using ~ DBCP2 Connection Pool with Java 7[try-with-resources]

public class ConnectionPool {
    static final BasicDataSource ds_dbcp2 = new BasicDataSource();
    static final ComboPooledDataSource ds_c3p0 = new ComboPooledDataSource();
    static final DataSource ds_JDBC = new DataSource();

    static Properties prop = new Properties();
    static {
        try {
            prop.load(ConnectionPool.class.getClassLoader().getResourceAsStream("connectionpool.properties"));

            ds_dbcp2.setDriverClassName( prop.getProperty("DriverClass") );
            ds_dbcp2.setUrl( prop.getProperty("URL") );
            ds_dbcp2.setUsername( prop.getProperty("UserName") );
            ds_dbcp2.setPassword( prop.getProperty("Password") );
            ds_dbcp2.setInitialSize( 5 );

            ds_c3p0.setDriverClass( prop.getProperty("DriverClass") );
            ds_c3p0.setJdbcUrl( prop.getProperty("URL") );
            ds_c3p0.setUser( prop.getProperty("UserName") );
            ds_c3p0.setPassword( prop.getProperty("Password") );
            ds_c3p0.setMinPoolSize(5);
            ds_c3p0.setAcquireIncrement(5);
            ds_c3p0.setMaxPoolSize(20);

            PoolProperties pool = new PoolProperties();
            pool.setUrl( prop.getProperty("URL") );
            pool.setDriverClassName( prop.getProperty("DriverClass") );
            pool.setUsername( prop.getProperty("UserName") );
            pool.setPassword( prop.getProperty("Password") );
            pool.setValidationQuery("SELECT 1");// SELECT 1(mysql) select 1 from dual(oracle)

            pool.setInitialSize(5);
            pool.setMaxActive(3);
            ds_JDBC.setPoolProperties( pool );
        } catch (IOException e) {   e.printStackTrace();
        } catch (PropertyVetoException e) { e.printStackTrace(); }
    }

    public static Connection getDBCP2Connection() throws SQLException {
        return ds_dbcp2.getConnection();
    }

    public static Connection getc3p0Connection() throws SQLException {
        return ds_c3p0.getConnection();
    }

    public static Connection getJDBCConnection() throws SQLException {
        return ds_JDBC.getConnection();
    }
}
public static boolean exists(String UserName, String Password ) throws SQLException {
    boolean exist = false;
    String SQL_EXIST = "SELECT * FROM users WHERE username=? AND password=?";
    try ( Connection connection = ConnectionPool.getDBCP2Connection();
          PreparedStatement pstmt = connection.prepareStatement(SQL_EXIST); ) {
        pstmt.setString(1, UserName );
        pstmt.setString(2, Password );

        try (ResultSet resultSet = pstmt.executeQuery()) {
            exist = resultSet.next(); // Note that you should not return a ResultSet here.
        }
    }
    System.out.println("User : "+exist);
    return exist;
}

jdbc:<DB>:<drivertype>:<HOST>:<TCP/IP PORT>:<dataBaseName> jdbc:oracle:thin:@localhost:1521:myDBName jdbc:mysql://localhost:3306/myDBName

connectionpool.properties

URL         : jdbc:mysql://localhost:3306/myDBName
DriverClass : com.mysql.jdbc.Driver
UserName    : root
Password    :

Web Application: To avoid connection problem when all the connection's are closed[MySQL "wait_timeout" default 8 hours] in-order to reopen the connection with underlying DB.

You can do this to Test Every Connection by setting testOnBorrow = true and validationQuery= "SELECT 1" and donot use autoReconnect for MySQL server as it is deprecated. issue

===== ===== context.xml ===== =====
<?xml version="1.0" encoding="UTF-8"?>
<!-- The contents of this file will be loaded for a web application -->
<Context>
    <Resource name="jdbc/MyAppDB" auth="Container" 
        factory="org.apache.tomcat.jdbc.pool.DataSourceFactory" 
        type="javax.sql.DataSource" 

        initialSize="5" minIdle="5" maxActive="15" maxIdle="10"

        testWhileIdle="true"
            timeBetweenEvictionRunsMillis="30000"

        testOnBorrow="true"
            validationQuery="SELECT 1"
            validationInterval="30000"


        driverClassName="com.mysql.jdbc.Driver" 
        url="jdbc:mysql://localhost:3306/myDBName" 
        username="yash" password="777"
    />
</Context>

===== ===== web.xml ===== =====
<resource-ref>
    <description>DB Connection</description>
    <res-ref-name>jdbc/MyAppDB</res-ref-name>
    <res-type>javax.sql.DataSource</res-type>
    <res-auth>Container</res-auth>
</resource-ref>
===== ===== DBOperations ===== =====
servlet «   init() {}
Normal call used by sevlet  « static {}

static DataSource ds;
static {
    try {
        Context ctx=new InitialContext();
        Context envContext = (Context)ctx.lookup("java:comp/env");
        ds  =   (DataSource) envContext.lookup("jdbc/MyAppDB");
    } catch (NamingException e) {   e.printStackTrace();    }
}

See these also:

Remove URL parameters without refreshing page

I belive the best and simplest method for this is:

var newURL = location.href.split("?")[0];
window.history.pushState('object', document.title, newURL);

Json.net serialize/deserialize derived types?

Since the question is so popular, it may be useful to add on what to do if you want to control the type property name and its value.

The long way is to write custom JsonConverters to handle (de)serialization by manually checking and setting the type property.

A simpler way is to use JsonSubTypes, which handles all the boilerplate via attributes:

[JsonConverter(typeof(JsonSubtypes), "Sound")]
[JsonSubtypes.KnownSubType(typeof(Dog), "Bark")]
[JsonSubtypes.KnownSubType(typeof(Cat), "Meow")]
public class Animal
{
    public virtual string Sound { get; }
    public string Color { get; set; }
}

public class Dog : Animal
{
    public override string Sound { get; } = "Bark";
    public string Breed { get; set; }
}

public class Cat : Animal
{
    public override string Sound { get; } = "Meow";
    public bool Declawed { get; set; }
}

How to scroll to top of the page in AngularJS?

You can use

$window.scrollTo(x, y);

where x is the pixel along the horizontal axis and y is the pixel along the vertical axis.

  1. Scroll to top

    $window.scrollTo(0, 0);
    
  2. Focus on element

    $window.scrollTo(0, angular.element('put here your element').offsetTop);   
    

Example

Update:

Also you can use $anchorScroll

Example

moment.js, how to get day of week number

I think this would work

moment().weekday(); //if today is thursday it will return 4

Is there shorthand for returning a default value if None in Python?

You can use a conditional expression:

x if x is not None else some_value

Example:

In [22]: x = None

In [23]: print x if x is not None else "foo"
foo

In [24]: x = "bar"

In [25]: print x if x is not None else "foo"
bar

Python module for converting PDF to text

PDFminer gave me perhaps one line [page 1 of 7...] on every page of a pdf file I tried with it.

The best answer I have so far is pdftoipe, or the c++ code it's based on Xpdf.

see my question for what the output of pdftoipe looks like.

What is a magic number, and why is it bad?

A magic number is a sequence of characters at the start of a file format, or protocol exchange. This number serves as a sanity check.

Example: Open up any GIF file, you will see at the very start: GIF89. "GIF89" being the magic number.

Other programs can read the first few characters of a file and properly identify GIFs.

The danger is that random binary data can contain these same characters. But it is very unlikely.

As for protocol exchange, you can use it to quickly identify that the current 'message' that is being passed to you is corrupted or not valid.

Magic numbers are still useful.

CSS background image to fit width, height should auto-scale in proportion

I'm not sure what you're looking for exactly, but you really should check out these excellent blog posts written by Chris Coyier from CSS-Tricks:

http://css-tricks.com/how-to-resizeable-background-image/

http://css-tricks.com/perfect-full-page-background-image/

Read the descriptions for each of the articles and see if they're what you're looking for.

The first answers the following question:

Is there a way to make a background image resizeable? As in, fill the background of a web page edge-to-edge with an image, no matter the size of the browser window. Also, have it resize larger or smaller as the browser window changes. Also, make sure it retains its ratio (doesn't stretch weird). Also, doesn't cause scrollbars, just cuts off vertically if it needs to. Also, comes in on the page as an inline tag.

The second post's goal is to get the following, a "background image on a website that covers the entire browser window at all times. "

Hope this helps.

Create a simple Login page using eclipse and mysql

You Can simply Use One Jsp Page To accomplish the task.

<%@page contentType="text/html" pageEncoding="UTF-8"%>
<%@page import="java.sql.*"%>
<!DOCTYPE html>
<html>
   <head>
    <meta http-equiv="Content-Type" content="text/html; charset=UTF-8">
    <title>JSP Page</title>
</head>
<body>
    <%
        String username=request.getParameter("user_name");
        String password=request.getParameter("password");
        String role=request.getParameter("role");
        try
        {
            Class.forName("com.mysql.jdbc.Driver");
            Connection con=DriverManager.getConnection("jdbc:mysql://localhost:3306/t_fleet","root","root");
            Statement st=con.createStatement();
            String query="select * from tbl_login where user_name='"+username+"' and password='"+password+"' and role='"+role+"'";
            ResultSet rs=st.executeQuery(query);
            while(rs.next())
            {
                session.setAttribute( "user_name",rs.getString(2));
                session.setMaxInactiveInterval(3000);
                response.sendRedirect("homepage.jsp");
            }
            %>



        <%}
        catch(Exception e)
        {
            out.println(e);
        }
    %>

</body>

I have use username, password and role to get into the system. One more thing to implement is you can do page permission checking through jsp and javascript function.

Fastest way to update 120 Million records

If the table has an index which you can iterate over I would put update top(10000) statement in a while loop moving over the data. That would keep the transaction log slim and won't have such a huge impact on the disk system. Also, I would recommend to play with maxdop option (setting it closer to 1).

Access Session attribute on jstl

You don't need the jsp:useBean to set the model if you already have a controller which prepared the model.

Just access it plain by EL:

<p>${Questions.questionPaperID}</p>
<p>${Questions.question}</p>

or by JSTL <c:out> tag if you'd like to HTML-escape the values or when you're still working on legacy Servlet 2.3 containers or older when EL wasn't supported in template text yet:

<p><c:out value="${Questions.questionPaperID}" /></p>
<p><c:out value="${Questions.question}" /></p>

See also:


Unrelated to the problem, the normal practice is by the way to start attribute name with a lowercase, like you do with normal variable names.

session.setAttribute("questions", questions);

and alter EL accordingly to use ${questions}.

Also note that you don't have any JSTL tag in your code. It's all plain JSP.

How do I drop a foreign key constraint only if it exists in sql server?

In SQL Server 2016 you can use DROP IF EXISTS:

CREATE TABLE t(id int primary key, 
               parentid int
                    constraint tpartnt foreign key references t(id))
GO
ALTER TABLE t
DROP CONSTRAINT IF EXISTS tpartnt
GO
DROP TABLE IF EXISTS t

See http://blogs.msdn.com/b/sqlserverstorageengine/archive/2015/11/03/drop-if-exists-new-thing-in-sql-server-2016.aspx

Content type 'application/x-www-form-urlencoded;charset=UTF-8' not supported for @RequestBody MultiValueMap

Add a header to your request to set content type to application/json

curl -H 'Content-Type: application/json' -s -XPOST http://your.domain.com/ -d YOUR_JSON_BODY

this way spring knows how to parse the content.

How do you properly return multiple values from a Promise?

You can return an object containing both values — there's nothing wrong with that.

Another strategy is to keep the value, via closures, instead of passing it through:

somethingAsync().then(afterSomething);

function afterSomething(amazingData) {
  return processAsync(amazingData).then(function (processedData) {
    // both amazingData and processedData are in scope here
  });
}

Fully rather than partially inlined form (equivalent, arguably more consistent):

somethingAsync().then(function (amazingData) {
  return processAsync(amazingData).then(function (processedData) {
    // both amazingData and processedData are in scope here
  });
}

Passing array in GET for a REST call

Instead of using http GET, use http POST. And JSON. Or XML

This is how your request stream to the server would look like.

POST /appointments HTTP/1.0
Content-Type: application/json
Content-Length: (calculated by your utility)

{users: [user:{id:id1}, user:{id:id2}]}

Or in XML,

POST /appointments HTTP/1.0
Content-Type: application/json
Content-Length: (calculated by your utility)

<users><user id='id1'/><user id='id2'/></users>

You could certainly continue using GET as you have proposed, as it is certainly simpler.

/appointments?users=1d1,1d2

Which means you would have to keep your data structures very simple.

However, if/when your data structure gets more complex, http GET and without JSON, your programming and ability to recognise the data gets very difficult.

Therefore,unless you could keep your data structure simple, I urge you adopt a data transfer framework. If your requests are browser based, the industry usual practice is JSON. If your requests are server-server, than XML is the most convenient framework.

JQuery

If your client is a browser and you are not using GWT, you should consider using jquery REST. Google on RESTful services with jQuery.

Can an interface extend multiple interfaces in Java?

From the Oracle documentation page about multiple inheritance type,we can find the accurate answer here. Here we should first know the type of multiple inheritance in java:-

  1. Multiple inheritance of state.
  2. Multiple inheritance of implementation.
  3. Multiple inheritance of type.

Java "doesn't support the multiple inheritance of state, but it support multiple inheritance of implementation with default methods since java 8 release and multiple inheritance of type with interfaces.

Then here the question arises for "diamond problem" and how Java deal with that:-

  1. In case of multiple inheritance of implementation java compiler gives compilation error and asks the user to fix it by specifying the interface name. Example here:-

                interface A {
                    void method();
                }
    
                interface B extends A {
                    @Override
                    default void method() {
                        System.out.println("B");
                    }
                }
    
                interface C extends A { 
                    @Override
                    default void method() {
                        System.out.println("C");
                    }
                }
    
                interface D extends B, C {
    
                }
    

So here we will get error as:- interface D inherits unrelated defaults for method() from types B and C interface D extends B, C

You can fix it like:-

interface D extends B, C {
                @Override
                default void method() {
                    B.super.method();
                }
            }
  1. In multiple inheritance of type java allows it because interface doesn't contain mutable fields and only one implementation will belong to the class so java doesn't give any issue and it allows you to do so.

In Conclusion we can say that java doesn't support multiple inheritance of state but it does support multiple inheritance of implementation and multiple inheritance of type.

ActiveRecord find and only return selected columns

In Rails 2

l = Location.find(:id => id, :select => "name, website, city", :limit => 1)

...or...

l = Location.find_by_sql(:conditions => ["SELECT name, website, city FROM locations WHERE id = ? LIMIT 1", id])

This reference doc gives you the entire list of options you can use with .find, including how to limit by number, id, or any other arbitrary column/constraint.

In Rails 3 w/ActiveRecord Query Interface

l = Location.where(["id = ?", id]).select("name, website, city").first

Ref: Active Record Query Interface

You can also swap the order of these chained calls, doing .select(...).where(...).first - all these calls do is construct the SQL query and then send it off.