Programs & Examples On #Sstream

What exactly does stringstream do?

Sometimes it is very convenient to use stringstream to convert between strings and other numerical types. The usage of stringstream is similar to the usage of iostream, so it is not a burden to learn.

Stringstreams can be used to both read strings and write data into strings. It mainly functions with a string buffer, but without a real I/O channel.

The basic member functions of stringstream class are

  • str(), which returns the contents of its buffer in string type.

  • str(string), which set the contents of the buffer to the string argument.

Here is an example of how to use string streams.

ostringstream os;
os << "dec: " << 15 << " hex: " << std::hex << 15 << endl;
cout << os.str() << endl;

The result is dec: 15 hex: f.

istringstream is of more or less the same usage.

To summarize, stringstream is a convenient way to manipulate strings like an independent I/O device.

FYI, the inheritance relationships between the classes are:

string stream classes

Creating a Zoom Effect on an image on hover using CSS?

SOLUTION 1: You can download zoom-master.
SOLUTION 2: Go to here .
SOLUTION 3: Your own codes

_x000D_
_x000D_
.hover-zoom {_x000D_
    -moz-transition:all 0.3s;_x000D_
    -webkit-transition:all 0.3s;_x000D_
     transition:all 0.3s_x000D_
 }_x000D_
.hover-zoom:hover {_x000D_
    -moz-transform: scale(1.1);_x000D_
    -webkit-transform: scale(1.1);_x000D_
     transform: scale(1.5)_x000D_
 }
_x000D_
<img class="hover-zoom"  src="https://i.stack.imgur.com/ewRqh.jpg" _x000D_
     width="100px"/>
_x000D_
_x000D_
_x000D_


How to send a pdf file directly to the printer using JavaScript?

a function to house the print trigger...

function printTrigger(elementId) {
    var getMyFrame = document.getElementById(elementId);
    getMyFrame.focus();
    getMyFrame.contentWindow.print();
}

an button to give the user access...

(an onClick on an a or button or input or whatever you wish)

<input type="button" value="Print" onclick="printTrigger('iFramePdf');" />
an iframe pointing to your PDF...

<iframe id="iFramePdf" src="myPdfUrl.pdf" style="dispaly:none;"></iframe>

More : http://www.fpdf.org/en/script/script36.php

How to add native library to "java.library.path" with Eclipse launch (instead of overriding it)

The solution offered by Rob Elsner in one of the comments above works perfectly (OSX 10.9, Eclipse Kepler). One has to append their additional paths to that separated by ":".

You could also use ${system_property:java.library.path} – Rob Elsner Nov 22 '10 at 23:01

How to give a time delay of less than one second in excel vba?

Everyone tries Application.Wait, but that's not really reliable. If you ask it to wait for less than a second, you'll get anything between 0 and 1, but closer to 10 seconds. Here's a demonstration using a wait of 0.5 seconds:

Sub TestWait()
  Dim i As Long
  For i = 1 To 5
    Dim t As Double
    t = Timer
    Application.Wait Now + TimeValue("0:00:00") / 2
    Debug.Print Timer - t
  Next
End Sub

Here's the output, an average of 0.0015625 seconds:

0
0
0
0.0078125
0

Admittedly, Timer may not be the ideal way to measure these events, but you get the idea.

The Timer approach is better:

Sub TestTimer()
  Dim i As Long
  For i = 1 To 5
    Dim t As Double
    t = Timer
    Do Until Timer - t >= 0.5
      DoEvents
    Loop
    Debug.Print Timer - t
  Next
End Sub

And the results average is very close to 0.5 seconds:

0.5
0.5
0.5
0.5
0.5

Different ways of clearing lists

del list[:] 

Will delete the values of that list variable

del list

Will delete the variable itself from memory

How to create a vector of user defined size but with no predefined values?

With the constructor:

// create a vector with 20 integer elements
std::vector<int> arr(20);

for(int x = 0; x < 20; ++x)
   arr[x] = x;

How can I debug what is causing a connection refused or a connection time out?

Use a packet analyzer to intercept the packets to/from somewhere.com. Studying those packets should tell you what is going on.

Time-outs or connections refused could mean that the remote host is too busy.

ImportError: No module named pandas

When I try to build docker image zeppelin-highcharts, I find that the base image openjdk:8 also does not have pandas installed. I solved it with this steps.

curl --silent --show-error --retry 5 https://bootstrap.pypa.io/get-pip.py | python
pip install pandas

I refered what-is-the-official-preferred-way-to-install-pip-and-virtualenv-systemwide

pip install failing with: OSError: [Errno 13] Permission denied on directory

User doesn't have write permission for some Python installation paths. You can give the permission by:

sudo chown -R $USER /absolute/path/to/directory

So you should give permission, then try to install it again, if you have new paths you should also give permission:

sudo chown -R $USER /usr/local/lib/python2.7/

Add back button to action bar

if anyone else need the solution

@Override
public boolean onOptionsItemSelected(MenuItem item) {
    int id = item.getItemId();

    if (id == android.R.id.home) {
        onBackPressed();
    }

    return super.onOptionsItemSelected(item);
}

Align DIV's to bottom or baseline

this works (i only tested ie & ff):

<html>
<head>
    <style type="text/css">
        #parent {
            height: 300px;
            width: 300px;
            background-color: #ccc;
            border: 1px solid red;
            position: relative;
        }
        #child  {
            height: 100px;
            width: 30px;
            background-color: #eee;
            border: 1px solid green;
            position: absolute;
            bottom: 0;
            left: 0;
        }
    </style>
</head>
<body>
    <div id="parent">parent
        <div id="child">child</div>
    </div>
    outside
</body>
</html>

hope that helps.

VBA Macro to compare all cells of two Excel files

A very simple check you can do with Cell formulas:

Sheet 1 (new - old)

=(if(AND(Ref_New<>"";Ref_Old="");Ref_New;"")

Sheet 2 (old - new)

=(if(AND(Ref_Old<>"";Ref_New="");Ref_Old;"")

This formulas should work for an ENGLISH Excel. For other languages they need to be translated. (For German i can assist)

You need to open all three Excel Documents, then copy the first formula into A1 of your sheet 1 and the second into A1 of sheet 2. Now click in A1 of the first cell and mark "Ref_New", now you can select your reference, go to the new file and click in the A1, go back to sheet1 and do the same for "Ref_Old" with the old file. Replace also the other "Ref_New".

Doe the same for Sheet two.

Now copy the formaula form A1 over the complete range where zour data is in the old and the new file.

But two cases are not covered here:

  1. In the compared cell of New and Old is the same data (Resulting Cell will be empty)
  2. In the compared cell of New and Old is diffe data (Resulting Cell will be empty)

To cover this two cases also, you should create your own function, means learn VBA. A very useful Excel page is cpearson.com

How to use Bootstrap in an Angular project?

If you use angular cli, after adding bootstrap into package.json and install the package, all you need is add boostrap.min.css into .angular-cli.json's "styles" section.

One important thing is "When you make changes to .angular-cli.json you will need to re-start ng serve to pick up configuration changes."

Ref:

https://github.com/angular/angular-cli/wiki/stories-include-bootstrap

What is your favorite C programming trick?

#if TESTMODE == 1    
    debug=1;
    while(0);     // Get attention
#endif

The while(0); has no effect on the program, but the compiler will issue a warning about "this does nothing", which is enough to get me to go look at the offending line and then see the real reason I wanted to call attention to it.

"webxml attribute is required" error in Maven

This is because you have not included web.xml in your web project and trying to build war using maven. To resolve this error, you need to set the failOnMissingWebXml to false in pom.xml file.

For example:

<properties>
    <failOnMissingWebXml>false</failOnMissingWebXml>   
</properties>

Please see the blog for more details: https://ankurjain26.blogspot.in/2017/05/error-assembling-war-webxml-attribute.html

Android: Color To Int conversion

All the methods and variables in Color are static. You can not instantiate a Color object.

Official Color Docs

The Color class defines methods for creating and converting color ints.

Colors are represented as packed ints, made up of 4 bytes: alpha, red, green, blue.

The values are unpremultiplied, meaning any transparency is stored solely in the alpha component, and not in the color components.

The components are stored as follows (alpha << 24) | (red << 16) | (green << 8) | blue.

Each component ranges between 0..255 with 0 meaning no contribution for that component, and 255 meaning 100% contribution.

Thus opaque-black would be 0xFF000000 (100% opaque but no contributions from red, green, or blue), and opaque-white would be 0xFFFFFFFF

Swift double to string

It is not casting, it is creating a string from a value with a format.

let a: Double = 1.5
let b: String = String(format: "%f", a)

print("b: \(b)") // b: 1.500000

With a different format:

let c: String = String(format: "%.1f", a)

print("c: \(c)") // c: 1.5

You can also omit the format property if no formatting is needed.

In Firebase, is there a way to get the number of children of a node without loading all the node data?

write a cloud function to and update the node count.

// below function to get the given node count.
const functions = require('firebase-functions');
const admin = require('firebase-admin');
admin.initializeApp(functions.config().firebase);

exports.userscount = functions.database.ref('/users/')
    .onWrite(event => {

      console.log('users number : ', event.data.numChildren());


      return event.data.ref.parent.child('count/users').set(event.data.numChildren());
    }); 

Refer :https://firebase.google.com/docs/functions/database-events

root--| |-users ( this node contains all users list) |
|-count |-userscount : (this node added dynamically by cloud function with the user count)

How to remove outliers in boxplot in R?

See ?boxplot for all the help you need.

 outline: if ‘outline’ is not true, the outliers are not drawn (as
          points whereas S+ uses lines).

boxplot(x,horizontal=TRUE,axes=FALSE,outline=FALSE)

And for extending the range of the whiskers and suppressing the outliers inside this range:

   range: this determines how far the plot whiskers extend out from the
          box.  If ‘range’ is positive, the whiskers extend to the most
          extreme data point which is no more than ‘range’ times the
          interquartile range from the box. A value of zero causes the
          whiskers to extend to the data extremes.

# change the value of range to change the whisker length
boxplot(x,horizontal=TRUE,axes=FALSE,range=2)

Reading RFID with Android phones

I recently worked on a project to read the RFID tags. The project used the Devices from manufacturers like Zebra (we were using RFD8500 ) & TSL.

More devices are from Motorola & other vendors as well!

We have to use the native SDK api's provided by the manufacturer, how it works is by pairing the device by the Bluetooth of the phones and so the data transfer between both devices take place! The programming is based on subscribe pattern where the scan should be read by the device trigger(hardware trigger) or soft trigger (from the application).

The Tag read gives us the tagId & the RSSI which is the distance factor from the RFID tags!

This is the sample app:

We get all the device paired to our Android/iOS phones :

get device list

connect

connected

Scan

MD5 is 128 bits but why is it 32 characters?

That's 32 hex characters - 1 hex character is 4 bits.

Gradle's dependency cache may be corrupt (this sometimes occurs after a network connection timeout.)

If it has happened after upgrading Android Studio, It can be caused by an out of date buildtool, Update Android SDK BuildTools

Adding delay between execution of two following lines

Like @Sunkas wrote, performSelector:withObject:afterDelay: is the pendant to the dispatch_after just that it is shorter and you have the normal objective-c syntax. If you need to pass arguments to the block you want to delay, you can just pass them through the parameter withObject and you will receive it in the selector you call:

[self performSelector:@selector(testStringMethod:) 
           withObject:@"Test Test" 
           afterDelay:0.5];

- (void)testStringMethod:(NSString *)string{
    NSLog(@"string  >>> %@", string);
}

If you still want to choose yourself if you execute it on the main thread or on the current thread, there are specific methods which allow you to specify this. Apples Documentation tells this:

If you want the message to be dequeued when the run loop is in a mode other than the default mode, use the performSelector:withObject:afterDelay:inModes: method instead. If you are not sure whether the current thread is the main thread, you can use the performSelectorOnMainThread:withObject:waitUntilDone: or performSelectorOnMainThread:withObject:waitUntilDone:modes: method to guarantee that your selector executes on the main thread. To cancel a queued message, use the cancelPreviousPerformRequestsWithTarget: or cancelPreviousPerformRequestsWithTarget:selector:object: method.

How to use null in switch

Some libraries attempt to offer alternatives to the builtin java switch statement. Vavr is one of them, they generalize it to pattern matching.

Here is an example from their documentation:

String s = Match(i).of(
    Case($(1), "one"),
    Case($(2), "two"),
    Case($(), "?")
);

You can use any predicate, but they offer many of them out of the box, and $(null) is perfectly legal. I find this a more elegant solution than the alternatives, but this requires java8 and a dependency on the vavr library...

How To: Best way to draw table in console app (C#)

class ArrayPrinter
    {
    #region Declarations

    static bool isLeftAligned = false;
    const string cellLeftTop = "+";
    const string cellRightTop = "+";
    const string cellLeftBottom = "+";
    const string cellRightBottom = "+";
    const string cellHorizontalJointTop = "-";
    const string cellHorizontalJointbottom = "-";
    const string cellVerticalJointLeft = "+";
    const string cellTJoint = "+";
    const string cellVerticalJointRight = "¦";
    const string cellHorizontalLine = "-";
    const string cellVerticalLine = "¦";

    #endregion

    #region Private Methods

    private static int GetMaxCellWidth(string[,] arrValues)
    {
        int maxWidth = 1;

        for (int i = 0; i < arrValues.GetLength(0); i++)
        {
            for (int j = 0; j < arrValues.GetLength(1); j++)
            {
                int length = arrValues[i, j].Length;
                if (length > maxWidth)
                {
                    maxWidth = length;
                }
            }
        }

        return maxWidth;
    }

    private static string GetDataInTableFormat(string[,] arrValues)
    {
        string formattedString = string.Empty;

        if (arrValues == null)
            return formattedString;

        int dimension1Length = arrValues.GetLength(0);
        int dimension2Length = arrValues.GetLength(1);

        int maxCellWidth = GetMaxCellWidth(arrValues);
        int indentLength = (dimension2Length * maxCellWidth) + (dimension2Length - 1);
        //printing top line;
        formattedString = string.Format("{0}{1}{2}{3}", cellLeftTop, Indent(indentLength), cellRightTop, System.Environment.NewLine);

        for (int i = 0; i < dimension1Length; i++)
        {
            string lineWithValues = cellVerticalLine;
            string line = cellVerticalJointLeft;
            for (int j = 0; j < dimension2Length; j++)
            {
                string value = (isLeftAligned) ? arrValues[i, j].PadRight(maxCellWidth, ' ') : arrValues[i, j].PadLeft(maxCellWidth, ' ');
                lineWithValues += string.Format("{0}{1}", value, cellVerticalLine);
                line += Indent(maxCellWidth);
                if (j < (dimension2Length - 1))
                {
                    line += cellTJoint;
                }
            }
            line += cellVerticalJointRight;
            formattedString += string.Format("{0}{1}", lineWithValues, System.Environment.NewLine);
            if (i < (dimension1Length - 1))
            {
                formattedString += string.Format("{0}{1}", line, System.Environment.NewLine);
            }
        }

        //printing bottom line
        formattedString += string.Format("{0}{1}{2}{3}", cellLeftBottom, Indent(indentLength), cellRightBottom, System.Environment.NewLine);
        return formattedString;
    }

    private static string Indent(int count)
    {
        return string.Empty.PadLeft(count, '-');                 
    }

    #endregion

    #region Public Methods

    public static void PrintToStream(string[,] arrValues, StreamWriter writer)
    {
        if (arrValues == null)
            return;

        if (writer == null)
            return;

        writer.Write(GetDataInTableFormat(arrValues));
    }

    public static void PrintToConsole(string[,] arrValues)
    {
        if (arrValues == null)
            return;

        Console.WriteLine(GetDataInTableFormat(arrValues));
    }

    #endregion

    static void Main(string[] args)
    {           
        int value = 997;
        string[,] arrValues = new string[5, 5];
        for (int i = 0; i < arrValues.GetLength(0); i++)
        {
            for (int j = 0; j < arrValues.GetLength(1); j++)
            {
                value++;
                arrValues[i, j] = value.ToString();
            }
        }
        ArrayPrinter.PrintToConsole(arrValues);
        Console.ReadLine();
    }
}

Elasticsearch error: cluster_block_exception [FORBIDDEN/12/index read-only / allow delete (api)], flood stage disk watermark exceeded

This happens when Elasticsearch thinks the disk is running low on space so it puts itself into read-only mode.

By default Elasticsearch's decision is based on the percentage of disk space that's free, so on big disks this can happen even if you have many gigabytes of free space.

The flood stage watermark is 95% by default, so on a 1TB drive you need at least 50GB of free space or Elasticsearch will put itself into read-only mode.

For docs about the flood stage watermark see https://www.elastic.co/guide/en/elasticsearch/reference/6.2/disk-allocator.html.

The right solution depends on the context - for example a production environment vs a development environment.

Solution 1: free up disk space

Freeing up enough disk space so that more than 5% of the disk is free will solve this problem. Elasticsearch won't automatically take itself out of read-only mode once enough disk is free though, you'll have to do something like this to unlock the indices:

$ curl -XPUT -H "Content-Type: application/json" https://[YOUR_ELASTICSEARCH_ENDPOINT]:9200/_all/_settings -d '{"index.blocks.read_only_allow_delete": null}'

Solution 2: change the flood stage watermark setting

Change the "cluster.routing.allocation.disk.watermark.flood_stage" setting to something else. It can either be set to a lower percentage or to an absolute value. Here's an example of how to change the setting from the docs:

PUT _cluster/settings
{
  "transient": {
    "cluster.routing.allocation.disk.watermark.low": "100gb",
    "cluster.routing.allocation.disk.watermark.high": "50gb",
    "cluster.routing.allocation.disk.watermark.flood_stage": "10gb",
    "cluster.info.update.interval": "1m"
  }
}

Again, after doing this you'll have to use the curl command above to unlock the indices, but after that they should not go into read-only mode again.

How to set selected value of jquery select2?

For multiple values something like this:

$("#HouseIds").select2("val", @Newtonsoft.Json.JsonConvert.SerializeObject(Model.HouseIds));

which will translate to something like this

$("#HouseIds").select2("val", [35293,49525]);

What exactly is the meaning of an API?

Searches should include Wikipedia, which is surprisingly good for a number of programming concepts/terms such as Application Programming Interface:

What is an API?

An application programming interface (API) is a particular set of rules ('code') and specifications that software programs can follow to communicate with each other. It serves as an interface between different software programs and facilitates their interaction, similar to the way the user interface facilitates interaction between humans and computers.

How is it used?

The same way any set of rules are used.

When and where is it used?

Depends upon realm and API, naturally. Consider these:

  1. The x86 (IA-32) Instruction Set (very useful ;-)
  2. A BIOS interrupt call
  3. OpenGL which is often exposed as a C library
  4. Core Windows system calls: WinAPI
  5. The Classes and Methods in Ruby's core library
  6. The Document Object Model exposed by browsers to JavaScript
  7. Web services, such as those provided by Facebook's Graph API
  8. An implementation of a protocol such as JNI in Java

Happy coding.

align text center with android

Just add these 2 lines;

android:gravity="center_horizontal"
android:textAlignment="center"

Swift - Integer conversion to Hours/Minutes/Seconds

Another way would be convert seconds to date and take the components i.e seconds, minutes and hour from date itself. This solution has limitation only till 23:59:59

Extracting Nupkg files using command line

did the same thing like this:

clear
cd PACKAGE_DIRECTORY

function Expand-ZIPFile($file, $destination)
{
    $shell = New-Object -ComObject Shell.Application
    $zip = $shell.NameSpace($file)
    foreach($item in $zip.items())
    {
        $shell.Namespace($destination).copyhere($item)
    }
}

Dir *.nupkg | rename-item -newname {  $_.name  -replace ".nupkg",".zip"  }

Expand-ZIPFile "Package.1.0.0.zip" “DESTINATION_PATH”

Check if a div exists with jquery

As karim79 mentioned, the first is the most concise. However I could argue that the second is more understandable as it is not obvious/known to some Javascript/jQuery programmers that non-zero/false values are evaluated to true in if-statements. And because of that, the third method is incorrect.

Bootstrap Carousel : Remove auto slide

data-interval="false"

Add this to the corresponding div ...

PRINT statement in T-SQL

Do you have variables that are associated with these print statements been output? if so, I have found that if the variable has no value then the print statement will not be ouput.

Detect when input has a 'readonly' attribute

Try a simple way:

if($('input[readonly="readonly"]')){
   alert("foo");
}

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

Try this function

BOOL UIKeyboardIsVisible(){

BOOL keyboardVisible=NO;
// Locate non-UIWindow.
UIWindow *keyboardWindow = nil;
for (UIWindow *testWindow in [[UIApplication sharedApplication] windows]) {
    if (![[testWindow class] isEqual:[UIWindow class]]) {
        keyboardWindow = testWindow;
        break;
    }
}
// Locate UIKeyboard.
for (UIView *possibleKeyboard in [keyboardWindow subviews]) {
    // iOS 4 sticks the UIKeyboard inside a UIPeripheralHostView.
    if ([[possibleKeyboard description] hasPrefix:@"<UIPeripheralHostView"]) {
        keyboardVisible=YES;
    }
    if ([[possibleKeyboard description] hasPrefix:@"<UIKeyboard"]) {
        keyboardVisible=YES;
        break;
    }
}
return keyboardVisible;

}

from: iOS: How to access the `UIKeyboard`?

Check if xdebug is working

Starting with xdebug 3 you can use the following command line :

php -r "xdebug_info();"

And it will display useful information about your xdebug installation.

Plot logarithmic axes with matplotlib in python

if you want to change the base of logarithm, just add:

plt.yscale('log',base=2) 

Before Matplotlib 3.3, you would have to use basex/basey as the bases of log

Problem with converting int to string in Linq to entities

I solved a similar problem by placing the conversion of the integer to string out of the query. This can be achieved by putting the query into an object.

var items = from c in contacts
            select new 
            {
                Value = c.ContactId,
                Text = c.Name
            };
var itemList = new SelectList();
foreach (var item in items)
{
    itemList.Add(new SelectListItem{ Value = item.ContactId, Text = item.Name });
}

Why isn't ProjectName-Prefix.pch created automatically in Xcode 6?

Use :

$(PROJECT_DIR)/Project name/PrefixHeader.pch

Hide all elements with class using plain Javascript

As simple as the following:

let elements = document.querySelectorAll('.custom-class')

elements.forEach((item: any) => {
  item.style.display = 'none'
})

With that, you avoid all the looping, indexing, and such.

MySQL: How to reset or change the MySQL root password?

when changing/resetting the MySQL password the following commands listed above did not help. I found that going into the terminal and using these commands is pointless. instead use the command sudo stop everything. DELETE SYSTEM 32 for windows if that helps.

Eliminate extra separators below UITableView

Try with this

for Objective C

- (void)viewDidLoad 
 {
  [super viewDidLoad];
  // This will remove extra separators from tableview
  self.yourTableView.tableFooterView = [UIView new];
}

for Swift

override func viewDidLoad() {
 super.viewDidLoad()
 self.yourTableView.tableFooterView = UIView()
}

getting the index of a row in a pandas apply function

Either:

1. with row.name inside the apply(..., axis=1) call:

df = pandas.DataFrame([[1,2,3],[4,5,6]], columns=['a','b','c'], index=['x','y'])

   a  b  c
x  1  2  3
y  4  5  6

df.apply(lambda row: row.name, axis=1)

x    x
y    y

2. with iterrows() (slower)

DataFrame.iterrows() allows you to iterate over rows, and access their index:

for idx, row in df.iterrows():
    ...

How to get JQuery.trigger('click'); to initiate a mouse click

You can't simulate a click event with javascript. jQuery .trigger() function only fires an event named "click" on the element, which you can capture with .on() jQuery method.

How to monitor network calls made from iOS Simulator

Recently i found a git repo that makes it easy.

You can try it.

This is an app's screenshot: enter image description here

Best regards.

How to remove the focus from a TextBox in WinForms?

It seems that I don't have to set the focus to any other elements. On a Windows Phone 7 application, I've been using the Focus method to unset the Focus of a Textbox.

Giving the following command will set the focus to nothing:

void SearchBox_KeyDown(object sender, System.Windows.Input.KeyEventArgs e)
{
    if (e.Key == Key.Enter)
    {
        Focus();
    }
}

http://msdn.microsoft.com/en-us/library/system.windows.forms.control.focus.aspx

It worked for me, but I don't know why didn't it work for you :/

Split a string into an array of strings based on a delimiter

var  
    su  : string;        // What we want split
    si  : TStringList;   // Result of splitting
    Delimiter : string;
    ...
    Delimiter := ';';
    si.Text := ReplaceStr(su, Delimiter, #13#10);

Lines in si list will contain splitted strings.

Composer could not find a composer.json

I encountered the same error, and was able to solve it as follows:

  1. composer diagnose to see if something is wrong with the version of composer installed
  2. composer self-update to install the latest version
  3. composer update to update your composer.json file.

Save and retrieve image (binary) from SQL Server using Entity Framework 6

Convert the image to a byte[] and store that in the database.


Add this column to your model:

public byte[] Content { get; set; }

Then convert your image to a byte array and store that like you would any other data:

public byte[] ImageToByteArray(System.Drawing.Image imageIn)
{
    using(var ms = new MemoryStream())
    {
        imageIn.Save(ms, System.Drawing.Imaging.ImageFormat.Gif);

        return ms.ToArray();
    }
}

public Image ByteArrayToImage(byte[] byteArrayIn)
{
     using(var ms = new MemoryStream(byteArrayIn))
     {
         var returnImage = Image.FromStream(ms);

         return returnImage;
     }
}

Source: Fastest way to convert Image to Byte array

var image = new ImageEntity()
{
   Content = ImageToByteArray(image)
};

_context.Images.Add(image);
_context.SaveChanges();

When you want to get the image back, get the byte array from the database and use the ByteArrayToImage and do what you wish with the Image

This stops working when the byte[] gets to big. It will work for files under 100Mb

javascript compare strings without being case sensitive

You can also use string.match().

var string1 = "aBc";
var match = string1.match(/AbC/i);

if(match) {
}

jQuery detect if string contains something

You could use String.prototype.indexOf to accomplish that. Try something like this:

_x000D_
_x000D_
$('.type').keyup(function() {_x000D_
  var v = $(this).val();_x000D_
  if (v.indexOf('> <') !== -1) {_x000D_
    console.log('contains > <');_x000D_
  }_x000D_
  console.log(v);_x000D_
});
_x000D_
<script src="https://ajax.googleapis.com/ajax/libs/jquery/2.1.1/jquery.min.js"></script>_x000D_
<textarea class="type"></textarea>
_x000D_
_x000D_
_x000D_

Update

Modern browsers also have a String.prototype.includes method.

How to Replace dot (.) in a string in Java

If you want to replace a simple string and you don't need the abilities of regular expressions, you can just use replace, not replaceAll.

replace replaces each matching substring but does not interpret its argument as a regular expression.

str = xpath.replace(".", "/*/");

Remove 'b' character do in front of a string literal in Python 3

This should do the trick:

pw_bytes.decode("utf-8")

Regular Expression For Duplicate Words

I believe this regex handles more situations:

/(\b\S+\b)\s+\b\1\b/

A good selection of test strings can be found here: http://callumacrae.github.com/regex-tuesday/challenge1.html

Get a timestamp in C in microseconds?

You need to add in the seconds, too:

unsigned long time_in_micros = 1000000 * tv.tv_sec + tv.tv_usec;

Note that this will only last for about 232/106 =~ 4295 seconds, or roughly 71 minutes though (on a typical 32-bit system).

Is There a Better Way of Checking Nil or Length == 0 of a String in Ruby?

As it was said here before Rails (ActiveSupport) have a handy blank? method and it is implemented like this:

class Object
  def blank?
    respond_to?(:empty?) ? empty? : !self
  end
end

Pretty easy to add to any ruby-based project.

The beauty of this solution is that it works auto-magicaly not only for Strings but also for Arrays and other types.

How to overcome the CORS issue in ReactJS

the simplest way what I found from a tutorial of "TraversyMedia" is that just use https://cors-anywhere.herokuapp.com in 'axios' or 'fetch' api

https://cors-anywhere.herokuapp.com/{type_your_url_here} 

e.g.

axios.get(`https://cors-anywhere.herokuapp.com/https://www.api.com/`)

and in your case edit url as

url: 'https://cors-anywhere.herokuapp.com/https://www.api.com',

Using setTimeout to delay timing of jQuery actions

Try this:

function explode(){
  alert("Boom!");
}
setTimeout(explode, 2000);

S3 - Access-Control-Allow-Origin Header

I arrived at this thread, and none of the above solutions turned out to apply to my case. It turns out, I simply had to remove a trailing slash from the <AllowedOrigin> URL in my bucket's CORS configuration.

Fails:

<?xml version="1.0" encoding="UTF-8"?>
<CORSConfiguration xmlns="http://s3.amazonaws.com/doc/2006-03-01/">
    <CORSRule>
        <AllowedOrigin>http://www.mywebsite.com/</AllowedOrigin>
        <AllowedMethod>GET</AllowedMethod>
        <MaxAgeSeconds>3000</MaxAgeSeconds>
        <AllowedHeader>*</AllowedHeader>
    </CORSRule>
</CORSConfiguration>

Wins:

<?xml version="1.0" encoding="UTF-8"?>
<CORSConfiguration xmlns="http://s3.amazonaws.com/doc/2006-03-01/">
    <CORSRule>
        <AllowedOrigin>http://www.mywebsite.com</AllowedOrigin>
        <AllowedMethod>GET</AllowedMethod>
        <MaxAgeSeconds>3000</MaxAgeSeconds>
        <AllowedHeader>*</AllowedHeader>
    </CORSRule>
</CORSConfiguration>

I hope this saves someone some hair-pulling.

How to convert byte array to string and vice versa?

While base64 encoding is safe and one could argue "the right answer", I arrived here looking for a way to convert a Java byte array to/from a Java String as-is. That is, where each member of the byte array remains intact in its String counterpart, with no extra space required for encoding/transport.

This answer describing 8bit transparent encodings was very helpful for me. I used ISO-8859-1 on terabytes of binary data to convert back and forth successfully (binary <-> String) without the inflated space requirements needed for a base64 encoding, so is safe for my use-case - YMMV.

This was also helpful in explaining when/if you should experiment.

Multiple maven repositories in one gradle file

you have to do like this in your project level gradle file

allprojects {
    repositories {
        jcenter()
        maven { url "http://dl.appnext.com/" }
        maven { url "https://maven.google.com" }
    }
}

How do you add an array to another array in Ruby and not end up with a multi-dimensional result?

If the new data could be an array or a scalar, and you want to prevent the new data to be nested if it was an array, the splat operator is awesome! It returns a scalar for a scalar, and an unpacked list of arguments for an array.

1.9.3-p551 :020 > a = [1, 2]
 => [1, 2] 
1.9.3-p551 :021 > b = [3, 4]
 => [3, 4] 
1.9.3-p551 :022 > c = 5
 => 5 
1.9.3-p551 :023 > a.object_id
 => 6617020 
1.9.3-p551 :024 > a.push *b
 => [1, 2, 3, 4] 
1.9.3-p551 :025 > a.object_id
 => 6617020 
1.9.3-p551 :026 > a.push *c
 => [1, 2, 3, 4, 5] 
1.9.3-p551 :027 > a.object_id
 => 6617020 

Docker error: invalid reference format: repository name must be lowercase

On MacOS when your are working on an iCloud drive, your $PWD will contain a directory "Mobile Documents". It does not seem to like the space!

As a workaround, I copied my project to local drive where there is no space in the path to my project folder.

I do not see a way you can get around changnig the default path to iCloud which is ~/Library/Mobile Documents/com~apple~CloudDocs

The space in the path in "Mobile Documents" seems to be what docker run does not like.

Visual Studio Code: format is not using indent settings

Disable all plugins (then enable one by one and verify)

Install / upgrade gradle on Mac OS X

As mentioned in this tutorial, it's as simple as:

To install

brew install gradle

To upgrade

brew upgrade gradle

(using Homebrew of course)

Also see (finally) updated docs.

Cheers :)!

How to format a JavaScript date

Here is a script that does exactly what you want

https://github.com/UziTech/js-date-format

var d = new Date("2010-8-10");
document.write(d.format("DD-MMM-YYYY"));

What's a simple way to get a text input popup dialog box on an iPhone

UIAlertview *alt = [[UIAlertView alloc]initWithTitle:@"\n\n\n" message:nil delegate:nil cancelButtonTitle:nil otherButtonTitles:@"OK", nil];

UILabel *lbl1 = [[UILabel alloc]initWithFrame:CGRectMake(25,17, 100, 30)];
lbl1.text=@"User Name";

UILabel *lbl2 = [[UILabel alloc]initWithFrame:CGRectMake(25, 60, 80, 30)];
lbl2.text = @"Password";

UITextField *username=[[UITextField alloc]initWithFrame:CGRectMake(130, 17, 130, 30)];
UITextField *password=[[UITextField alloc]initWithFrame:CGRectMake(130, 60, 130, 30)];

lbl1.textColor = [UIColor whiteColor];
lbl2.textColor = [UIColor whiteColor];

[lbl1 setBackgroundColor:[UIColor clearColor]];
[lbl2 setBackgroundColor:[UIColor clearColor]];

username.borderStyle = UITextBorderStyleRoundedRect;
password.borderStyle = UITextBorderStyleRoundedRect;

[alt addSubview:lbl1];
[alt addSubview:lbl2];
[alt addSubview:username];
[alt addSubview:password];

[alt show];

Tests not running in Test Explorer

In my case it worked to update the MSTest nuget packages. Could reproduce this problem even on blank MSTest project and updating the packages worked.

react-native: command not found

If for some strange reasons, the path to react-native is not in the PATH, you should take note where the react-native executable is installed. Generally, the issue with command not found is because they are not in PATH.

For example, I use nodenv and run npm install -g react-native

/Users/khoa/.nodenv/versions/10.10.0/bin/react-native -> /Users/khoa/.nodenv/versions/10.10.0/lib/node_modules/react-native/local-cli/wrong-react-native.js

So I need to add that to my PATH

export PATH=$HOME/.nodenv/versions/10.10.0/bin:$PATH

You can verify with echo $PATH

Or you can use npx to execute local npm modules, for example

npx react-native run-ios --simulator='iPhone X'

How to verify a method is called two times with mockito verify()

Using the appropriate VerificationMode:

import static org.mockito.Mockito.atLeast;
import static org.mockito.Mockito.times;
import static org.mockito.Mockito.verify;

verify(mockObject, atLeast(2)).someMethod("was called at least twice");
verify(mockObject, times(3)).someMethod("was called exactly three times");

Purpose of installing Twitter Bootstrap through npm?

If you NPM those modules you can serve them using static redirect.

First install the packages:

npm install jquery
npm install bootstrap

Then on the server.js:

var express = require('express');
var app = express();

// prepare server
app.use('/api', api); // redirect API calls
app.use('/', express.static(__dirname + '/www')); // redirect root
app.use('/js', express.static(__dirname + '/node_modules/bootstrap/dist/js')); // redirect bootstrap JS
app.use('/js', express.static(__dirname + '/node_modules/jquery/dist')); // redirect JS jQuery
app.use('/css', express.static(__dirname + '/node_modules/bootstrap/dist/css')); // redirect CSS bootstrap

Then, finally, at the .html:

<link rel="stylesheet" href="/css/bootstrap.min.css">
<script src="/js/jquery.min.js"></script>
<script src="/js/bootstrap.min.js"></script>

I would not serve pages directly from the folder where your server.js file is (which is usually the same as node_modules) as proposed by timetowonder, that way people can access your server.js file.

Of course you can simply download and copy & paste on your folder, but with NPM you can simply update when needed... easier, I think.

MVC3 EditorFor readOnly

<div class="editor-field">
        @Html.EditorFor(model => model.userName)
</div>

Use jquery to disable

<script type="text/javascript">
   $(document).ready(function () {
      $('#userName').attr('disabled', true);
     });
</script>

How to call webmethod in Asp.net C#

There are quite a few elements of the $.Ajax() that can cause issues if they are not defined correctly. I would suggest rewritting your javascript in its most basic form, you will most likely find that it works fine.

Script example:

$.ajax({
    type: "POST",
    url: '/Default.aspx/TestMethod',
    data: '{message: "HAI" }',
    contentType: "application/json; charset=utf-8",
    success: function (data) {
        console.log(data);
    },
    failure: function (response) {
        alert(response.d);
    }
});

WebMethod example:

[WebMethod]
public static string TestMethod(string message)
{
     return "The message" + message;
}

How to emit an event from parent to child?

Using RxJs, you can declare a Subject in your parent component and pass it as Observable to child component, child component just need to subscribe to this Observable.

Parent-Component

eventsSubject: Subject<void> = new Subject<void>();

emitEventToChild() {
  this.eventsSubject.next();
}

Parent-HTML

<child [events]="eventsSubject.asObservable()"> </child>    

Child-Component

private eventsSubscription: Subscription;

@Input() events: Observable<void>;

ngOnInit(){
  this.eventsSubscription = this.events.subscribe(() => doSomething());
}

ngOnDestroy() {
  this.eventsSubscription.unsubscribe();
}

What is the difference between Serializable and Externalizable in Java?

Some differences:

  1. For Serialization there is no need of default constructor of that class because Object because JVM construct the same with help of Reflection API. In case of Externalization contructor with no arg is required, because the control is in hand of programmar and later on assign the deserialized data to object via setters.

  2. In serialization if user want to skip certain properties to be serialized then has to mark that properties as transient, vice versa is not required for Externalization.

  3. When backward compatiblity support is expected for any class then it is recommended to go with Externalizable. Serialization supports defaultObject persisting and if object structure is broken then it will cause issue while deserializing.

Javascript to stop HTML5 video playback on modal window close

When you close the video you just need to pause it.

$("#closeSimple").click(function() {
    $("div#simpleModal").removeClass("show");
    $("#videoContainer")[0].pause();
    return false;                   
});

<video id="videoContainer" width="320" height="240" src="Davis_5109iPadFig3.m4v" controls="controls"> </video>

Also, for reference, here's the Opera documentation for scripting video controls.

Merge PDF files with PHP

I've done this before. I had a pdf that I generated with fpdf, and I needed to add on a variable amount of PDFs to it.

So I already had an fpdf object and page set up (http://www.fpdf.org/) And I used fpdi to import the files (http://www.setasign.de/products/pdf-php-solutions/fpdi/) FDPI is added by extending the PDF class:

class PDF extends FPDI
{

} 



    $pdffile = "Filename.pdf";
    $pagecount = $pdf->setSourceFile($pdffile);  
    for($i=0; $i<$pagecount; $i++){
        $pdf->AddPage();  
        $tplidx = $pdf->importPage($i+1, '/MediaBox');
        $pdf->useTemplate($tplidx, 10, 10, 200); 
    }

This basically makes each pdf into an image to put into your other pdf. It worked amazingly well for what I needed it for.

relative path to CSS file

Background

Absolute: The browser will always interpret / as the root of the hostname. For example, if my site was http://google.com/ and I specified /css/images.css then it would search for that at http://google.com/css/images.css. If your project root was actually at /myproject/ it would not find the css file. Therefore, you need to determine where your project folder root is relative to the hostname, and specify that in your href notation.

Relative: If you want to reference something you know is in the same path on the url - that is, if it is in the same folder, for example http://mysite.com/myUrlPath/index.html and http://mysite.com/myUrlPath/css/style.css, and you know that it will always be this way, you can go against convention and specify a relative path by not putting a leading / in front of your path, for example, css/style.css.

Filesystem Notations: Additionally, you can use standard filesystem notations like ... If you do http://google.com/images/../images/../images/myImage.png it would be the same as http://google.com/images/myImage.png. If you want to reference something that is one directory up from your file, use ../myFile.css.


Your Specific Case

In your case, you have two options:

  • <link rel="stylesheet" type="text/css" href="/ServletApp/css/styles.css"/>
  • <link rel="stylesheet" type="text/css" href="css/styles.css"/>

The first will be more concrete and compatible if you move things around, however if you are planning to keep the file in the same location, and you are planning to remove the /ServletApp/ part of the URL, then the second solution is better.

How to list records with date from the last 10 days?

Yes this does work in PostgreSQL (assuming the column "date" is of datatype date) Why don't you just try it?

The standard ANSI SQL format would be:

SELECT Table.date 
FROM Table 
WHERE date > current_date - interval '10' day;

I prefer that format as it makes things easier to read (but it is the same as current_date - 10).

Twitter - How to embed native video from someone else's tweet into a New Tweet or a DM

I found a faster way of embedding:

  • Just copy the link.
  • Paste the link and remove the "?s=19" part and add "/video/1"
  • That's it.

Create a List of primitive int?

In Java the type of any variable is either a primitive type or a reference type. Generic type arguments must be reference types. Since primitives do not extend Object they cannot be used as generic type arguments for a parametrized type.

Instead use the Integer class which is a wrapper for int:

List<Integer> list = new ArrayList<Integer>();

If your using Java 7 you can simplify this declaration using the diamond operator:

List<Integer> list = new ArrayList<>();

With autoboxing in Java the primitive type int will become an Integer when necessary.

Autoboxing is the automatic conversion that the Java compiler makes between the primitive types and their corresponding object wrapper classes.

So the following is valid:

int myInt = 1;
List<Integer> list = new ArrayList<Integer>();
list.add(myInt);

System.out.println(list.get(0)); //prints 1

oracle - what statements need to be committed?

DML have to be committed or rollbacked. DDL cannot.

http://www.orafaq.com/faq/what_are_the_difference_between_ddl_dml_and_dcl_commands

You can switch auto-commit on and that's again only for DML. DDL are never part of transactions and therefore there is nothing like an explicit commit/rollback.

truncate is DDL and therefore commited implicitly.

Edit
I've to say sorry. Like @DCookie and @APC stated in the comments there exist sth like implicit commits for DDL. See here for a question about that on Ask Tom. This is in contrast to what I've learned and I am still a bit curious about.

powershell - extract file name and extension

Check the BaseName and Extension properties of the FileInfo object.

jQuery issue in Internet Explorer 8

In short, it's because of the IE8 parsing engine.

Guess why Microsoft has trouble working with the new HTML5 tags (like "section") too? It's because MS decided that they will not use regular XML parsing, like the rest of the world. Yes, that's right - they did a ton of propaganda on XML but in the end, they fall back on a "stupid" parsing engine looking for "known tags" and messing stuff up when something new comes around.

Same goes for IE8 and the jquery issue with "load", "get" and "post". Again, Microsoft decided to "walk their own path" with version 8. Hoping that they solve(d) this in IE9, the only current option is to fall back on IE7 parsing with <meta http-equiv="X-UA-Compatible" content="IE=EmulateIE7" />.

Oh well... what a surprise that Microsoft made us post stuff on forums again. ;)

how do I join two lists using linq or lambda expressions

It sounds like you want something like:

var query = from order in workOrders
            join plan in plans
                 on order.WorkOrderNumber equals plan.WorkOrderNumber
            select new
            {
                order.WorkOrderNumber,
                order.Description,
                plan.ScheduledDate
            };

How can I run a windows batch file but hide the command window?

Create a shortcut to your bat file by using the right-click and selecting Create shortcut. Right-click on the shortcut you created and click on properties. Click on the Run drop-down box and select Minimized.

Plot multiple lines in one graph

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

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

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

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

enter image description here

Where IN clause in LINQ

This expression should do what you want to achieve.

dataSource.StateList.Where(s => countryCodes.Contains(s.CountryCode))

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

They're both the same thing, a lot of framework elements expose a name property themselves, but for those that don't you can use x:name - I usually just stick with x:name because it works for everything.

Controls can expose name themselves as a Dependency Property if they want to (because they need to use that Dependency Property internally), or they can choose not to.

More details in msdn here and here:

Some WPF framework-level applications might be able to avoid any use of the x:Name attribute, because the Name dependency property as specified within the WPF namespace for several of the important base classes such as FrameworkElement/FrameworkContentElement satisfies this same purpose. There are still some common XAML and framework scenarios where code access to an element with no Name property is necessary, most notably in certain animation and storyboard support classes. For instance, you should specify x:Name on timelines and transforms created in XAML, if you intend to reference them from code.

If Name is available as a property on the class, Name and x:Name can be used interchangeably as attributes, but an error will result if both are specified on the same element.

Read a file in Node.js

Run this code, it will fetch data from file and display in console

function fileread(filename)
{            
   var contents= fs.readFileSync(filename);
   return contents;
}        
var fs =require("fs");  // file system        
var data= fileread("abc.txt");
//module.exports.say =say;
//data.say();
console.log(data.toString());

Android Log.v(), Log.d(), Log.i(), Log.w(), Log.e() - When to use each one?

The Android Studio website has recently (I think) provided some advice what kind of messages to expect from different log levels that may be useful along with Kurtis' answer:

  • Verbose - Show all log messages (the default).
  • Debug - Show debug log messages that are useful during development only, as well as the message levels lower in this list.
  • Info - Show expected log messages for regular usage, as well as the message levels lower in this list.
  • Warn - Show possible issues that are not yet errors, as well as the message levels lower in this list.
  • Error - Show issues that have caused errors, as well as the message level lower in this list.
  • Assert - Show issues that the developer expects should never happen.

how to make log4j to write to the console as well

This works well for console in debug mode

log4j.appender.console=org.apache.log4j.ConsoleAppender
log4j.appender.console.Threshold=DEBUG
log4j.appender.console.Target=System.out
log4j.appender.console.layout=org.apache.log4j.PatternLayout
log4j.appender.console.layout.conversionPattern=%d{yyyy-MM-dd HH:mm:ss,SSS} %-5p - %m%n

How to align this span to the right of the div?

If you can modify the HTML: http://jsfiddle.net/8JwhZ/3/

<div class="title">
  <span class="name">Cumulative performance</span>
  <span class="date">20/02/2011</span>
</div>

.title .date { float:right }
.title .name { float:left }

How exactly does the python any() function work?

>>> names = ['King', 'Queen', 'Joker']
>>> any(n in 'King and john' for n in names)
True

>>> all(n in 'King and Queen' for n in names)
False

It just reduce several line of code into one. You don't have to write lengthy code like:

for n in names:
    if n in 'King and john':
       print True
    else:
       print False

Limit characters displayed in span

You can do this with jQuery :

_x000D_
_x000D_
$(document).ready(function(){_x000D_
  _x000D_
  $('.claimedRight').each(function (f) {_x000D_
_x000D_
      var newstr = $(this).text().substring(0,20);_x000D_
      $(this).text(newstr);_x000D_
_x000D_
    });_x000D_
})
_x000D_
<!DOCTYPE html>_x000D_
<html>_x000D_
<head>_x000D_
    <title></title>_x000D_
    <script         src="https://ajax.googleapis.com/ajax/libs/jquery/2.1.1/jquery.min.js"></script>_x000D_
</head>_x000D_
<body>_x000D_
    <span class="claimedRight" maxlength="20">Hello this is the first test string. _x000D_
    </span><br>_x000D_
    <span class="claimedRight" maxlength="20">Hello this is the second test string. _x000D_
    </span>_x000D_
    _x000D_
    _x000D_
</body>_x000D_
</html>
_x000D_
_x000D_
_x000D_

How to execute AngularJS controller function on page load?

On the one hand as @Mark-Rajcok said you can just get away with private inner function:

// at the bottom of your controller
var init = function () {
   // check if there is query in url
   // and fire search in case its value is not empty
};
// and fire it after definition
init();

Also you can take a look at ng-init directive. Implementation will be much like:

// register controller in html
<div data-ng-controller="myCtrl" data-ng-init="init()"></div>

// in controller
$scope.init = function () {
    // check if there is query in url
    // and fire search in case its value is not empty
};

But take care about it as angular documentation implies (since v1.2) to NOT use ng-init for that. However imo it depends on architecture of your app.

I used ng-init when I wanted to pass a value from back-end into angular app:

<div data-ng-controller="myCtrl" data-ng-init="init('%some_backend_value%')"></div>

Excel - find cell with same value in another worksheet and enter the value to the left of it

Assuming employee numbers are in the first column and their names are in the second:

=VLOOKUP(A1, Sheet2!A:B, 2,false)

Remove items from one list in another

In my case I had two different lists, with a common identifier, kind of like a foreign key. The second solution cited by "nzrytmn":

var result =  list1.Where(p => !list2.Any(x => x.ID == p.ID && x.property1 == p.property1)).ToList();

Was the one that best fit in my situation. I needed to load a DropDownList without the records that had already been registered.

Thank you !!!

This is my code:

t1 = new T1();
t2 = new T2();

List<T1> list1 = t1.getList();
List<T2> list2 = t2.getList();

ddlT3.DataSource= list2.Where(s => !list1.Any(p => p.Id == s.ID)).ToList();
ddlT3.DataTextField = "AnyThing";
ddlT3.DataValueField = "IdAnyThing";
ddlT3.DataBind();

How to loop through Excel files and load them into a database using SSIS package?

I had a similar issue and found that it was much simpler to to get rid of the Excel files as soon as possible. As part of the first steps in my package I used Powershell to extract the data out of the Excel files into CSV files. My own Excel files were simple but here

Extract and convert all Excel worksheets into CSV files using PowerShell

is an excellent article by Tim Smith on extracting data from multiple Excel files and/or multiple sheets.

Once the Excel files have been converted to CSV the data import is much less complicated.

How to increase icons size on Android Home Screen?

If you want to change settings in the launcher, change icon size, or grid size just hold down on an empty part of your home screen. Tap the three Dots and there you go.

From https://forums.oneplus.net/threads/how-to-change-icon-and-grid-size-trebuchet-settings.84820/

When configuring the phone for first time I saw something about a grid somewhere, but couldn't find it again. Luckily I found the answer on the link above.

PHP syntax question: What does the question mark and colon mean?

This is the PHP ternary operator (also known as a conditional operator) - if first operand evaluates true, evaluate as second operand, else evaluate as third operand.

Think of it as an "if" statement you can use in expressions. Can be very useful in making concise assignments that depend on some condition, e.g.

$param = isset($_GET['param']) ? $_GET['param'] : 'default';

There's also a shorthand version of this (in PHP 5.3 onwards). You can leave out the middle operand. The operator will evaluate as the first operand if it true, and the third operand otherwise. For example:

$result = $x ?: 'default';

It is worth mentioning that the above code when using i.e. $_GET or $_POST variable will throw undefined index notice and to prevent that we need to use a longer version, with isset or a null coalescing operator which is introduced in PHP7:

$param = $_GET['param'] ?? 'default';

IIS Config Error - This configuration section cannot be used at this path

I came across this thread and solve the issue by below steps, My problem may be different. Hope this can help some one .

In Turn windows feature on and off navigate to server roles and select the least below mentioned items .

enter image description here

Cheers !

C# string replace

Use:

line.Replace(@""",""", ";");

How to simulate a touch event in Android?

If I understand clearly, you want to do this programatically. Then, you could use the onTouchEvent method of View, and create a MotionEvent with the coordinates you need.

How do you performance test JavaScript code?

Quick answer

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

Long answer

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

What is a benchmark?

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

Should I benchmark my own application?

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

If not my own application, then what?

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

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

Performance testing JS

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

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

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

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

How do I find bottlenecks? Profilers

What is the best way to profile javascript execution?

How do I install g++ on MacOS X?

That's the compiler that comes with Apple's XCode tools package. They've hacked on it a little, but basically it's just g++.

You can download XCode for free (well, mostly, you do have to sign up to become an ADC member, but that's free too) here: http://developer.apple.com/technology/xcode.html

Edit 2013-01-25: This answer was correct in 2010. It needs an update.

While XCode tools still has a command-line C++ compiler, In recent versions of OS X (I think 10.7 and later) have switched to clang/llvm (mostly because Apple wants all the benefits of Open Source without having to contribute back and clang is BSD licensed). Secondly, I think all you have to do to install XCode is to download it from the App store. I'm pretty sure it's free there.

So, in order to get g++ you'll have to use something like homebrew (seemingly the current way to install Open Source software on the Mac (though homebrew has a lot of caveats surrounding installing gcc using it)), fink (basically Debian's apt system for OS X/Darwin), or MacPorts (Basically, OpenBSDs ports system for OS X/Darwin) to get it.

Fink definitely has the right packages. On 2016-12-26, it had gcc 5 and gcc 6 packages.

I'm less familiar with how MacPorts works, though some initial cursory investigation indicates they have the relevant packages as well.

docker-compose up for only certain containers

You usually don't want to do this. With Docker Compose you define services that compose your app. npm and manage.py are just management commands. You don't need a container for them. If you need to, say create your database tables with manage.py, all you have to do is:

docker-compose run client python manage.py create_db

Think of it as the one-off dynos Heroku uses.

If you really need to treat these management commands as separate containers (and also use Docker Compose for these), you could create a separate .yml file and start Docker Compose with the following command:

docker-compose up -f my_custom_docker_compose.yml

Set proxy through windows command line including login parameters

The best way around this is (and many other situations) in my experience, is to use cntlm which is a local no-authentication proxy which points to a remote authentication proxy. You can then just set WinHTTP to point to your local CNTLM (usually localhost:3128), and you can set CNTLM itself to point to the remote authentication proxy. CNTLM has a "magic NTLM dialect detection" option which generates password hashes to be put into the CNTLM configuration files.

Creating a JSON dynamically with each input value using jquery

I don't think you can turn JavaScript objects into JSON strings using only jQuery, assuming you need the JSON string as output.

Depending on the browsers you are targeting, you can use the JSON.stringify function to produce JSON strings.

See http://www.json.org/js.html for more information, there you can also find a JSON parser for older browsers that don't support the JSON object natively.

In your case:

var array = [];
$("input[class=email]").each(function() {
    array.push({
        title: $(this).attr("title"),
        email: $(this).val()
    });
});
// then to get the JSON string
var jsonString = JSON.stringify(array);

How to enable curl in Wamp server

The steps are as follows :

  1. Close WAMP (if running)
  2. Navigate to WAMP\bin\php\(your version of php)\
  3. Edit php.ini
  4. Search for curl, uncomment extension=php_curl.dll
  5. Navigate to WAMP\bin\Apache\(your version of apache)\bin\
  6. Edit php.ini
  7. Search for curl, uncomment extension=php_curl.dll
  8. Save both
  9. Restart WAMP

Remove menubar from Electron app

For Electron 7.1.1, you can use this:

const {app, BrowserWindow, Menu} = require('electron')
Menu.setApplicationMenu(false)

Do you use source control for your database items?

Yes, we source control our sql scripts too with subversion. It's a good practice and you can recreate the schema with default data whenever needed.

"Eliminate render-blocking CSS in above-the-fold content"

Consider using a package to automatically generate inline styles from your css files. A good one is Grunt Critical or Critical css for Laravel.

When do Java generics require <? extends T> instead of <T> and is there any downside of switching?

It boils down to:

Class<? extends Serializable> c1 = null;
Class<java.util.Date> d1 = null;
c1 = d1; // compiles
d1 = c1; // wont compile - would require cast to Date

You can see the Class reference c1 could contain a Long instance (since the underlying object at a given time could have been List<Long>), but obviously cannot be cast to a Date since there is no guarantee that the "unknown" class was Date. It is not typsesafe, so the compiler disallows it.

However, if we introduce some other object, say List (in your example this object is Matcher), then the following becomes true:

List<Class<? extends Serializable>> l1 = null;
List<Class<java.util.Date>> l2 = null;
l1 = l2; // wont compile
l2 = l1; // wont compile

...However, if the type of the List becomes ? extends T instead of T....

List<? extends Class<? extends Serializable>> l1 = null;
List<? extends Class<java.util.Date>> l2 = null;
l1 = l2; // compiles
l2 = l1; // won't compile

I think by changing Matcher<T> to Matcher<? extends T>, you are basically introducing the scenario similar to assigning l1 = l2;

It's still very confusing having nested wildcards, but hopefully that makes sense as to why it helps to understand generics by looking at how you can assign generic references to each other. It's also further confusing since the compiler is inferring the type of T when you make the function call (you are not explicitly telling it was T is).

Systrace for Windows

Here is a pretty intersting article, I don't know if it hits the target you are looking for but I think you may find it leading you in the direction you want.

http://jbremer.org/intercepting-system-calls-on-x86_64-windows/

Why doesn't Java allow overriding of static methods?

A Static method, variable, block or nested class belongs to the entire class rather than an object.

A Method in Java is used to expose the behaviour of an Object / Class. Here, as the method is static (i.e, static method is used to represent the behaviour of a class only.) changing/ overriding the behaviour of entire class will violate the phenomenon of one of the fundamental pillar of Object oriented programming i.e, high cohesion. (remember a constructor is a special kind of method in Java.)

High Cohesion - One class should have only one role. For example: A car class should produce only car objects and not bike, trucks, planes etc. But the Car class may have some features(behaviour) that belongs to itself only.

Therefore, while designing the java programming language. The language designers thought to allow developers to keep some behaviours of a class to itself only by making a method static in nature.


The below piece code tries to override the static method, but will not encounter any compilation error.

public class Vehicle {
static int VIN;

public static int getVehileNumber() {
    return VIN;
}}

class Car extends Vehicle {
static int carNumber;

public static int getVehileNumber() {
    return carNumber;
}}

This is because, here we are not overriding a method but we are just re-declaring it. Java allows re-declaration of a method (static/non-static).

Removing the static keyword from getVehileNumber() method of Car class will result into compilation error, Since, we are trying to change the functionality of static method which belongs to Vehicle class only.

Also, If the getVehileNumber() is declared as final then the code will not compile, Since the final keyword restricts the programmer from re-declaring the method.

public static final int getVehileNumber() {
return VIN;     }

Overall, this is upto software designers for where to use the static methods. I personally prefer to use static methods to perform some actions without creating any instance of a class. Secondly, to hide the behaviour of a class from outside world.

How to execute command stored in a variable?

If you just do eval $cmd when we do cmd="ls -l" (interactively and in a script) we get the desired result. In your case, you have a pipe with a grep without a pattern, so the grep part will fail with an error message. Just $cmd will generate a "command not found" (or some such) message. So try use eval and use a finished command, not one that generates an error message.

What does "res.render" do, and what does the html file look like?

Renders a view and sends the rendered HTML string to the client.

res.render('index');

Or

res.render('index', function(err, html) {
  if(err) {...}
  res.send(html);
});

DOCS HERE: https://expressjs.com/en/api.html#res.render

MySQL my.cnf performance tuning recommendations

Try starting with the Percona wizard and comparing their recommendations against your current settings one by one. Don't worry there aren't as many applicable settings as you might think.

https://tools.percona.com/wizard

Update circa 2020: Sorry, this tool reached it's end of life: https://www.percona.com/blog/2019/04/22/end-of-life-query-analyzer-and-mysql-configuration-generator/

Everyone points to key_buffer_size first which you have addressed. With 96GB memory I'd be wary of any tiny default value (likely to be only 96M!).

Can you get the column names from a SqlDataReader?

You sure can.


protected void GetColumNames_DataReader()
{
  System.Data.SqlClient.SqlConnection SqlCon = new System.Data.SqlClient.SqlConnection("server=localhost;database=northwind;trusted_connection=true");
  System.Data.SqlClient.SqlCommand SqlCmd = new System.Data.SqlClient.SqlCommand("SELECT * FROM Products", SqlCon);

  SqlCon.Open();

  System.Data.SqlClient.SqlDataReader SqlReader = SqlCmd.ExecuteReader();
  System.Int32 _columncount = SqlReader.FieldCount;

  System.Web.HttpContext.Current.Response.Write("SqlDataReader Columns");
  System.Web.HttpContext.Current.Response.Write(" ");

  for ( System.Int32 iCol = 0; iCol < _columncount; iCol ++ )
  {
    System.Web.HttpContext.Current.Response.Write("Column " + iCol.ToString() + ": ");
    System.Web.HttpContext.Current.Response.Write(SqlReader.GetName( iCol ).ToString());
    System.Web.HttpContext.Current.Response.Write(" ");
  }

}

This is originally from: http://www.dotnetjunkies.ddj.com/Article/B82A22D1-8437-4C7A-B6AA-C6C9BE9DB8A6.dcik

Maintain/Save/Restore scroll position when returning to a ListView

Isn't simply android:saveEnabled="true" in the ListView xml declaration enough?

Removing "bullets" from unordered list <ul>

ul.menu li a:before, ul.menu li .item:before, ul.menu li .separator:before {
  content: "\2022";
  font-family: FontAwesome;
  margin-right: 10px;
  display: inline;
  vertical-align: middle;
  font-size: 1.6em;
  font-weight: normal;
}

Is present in your site's CSS, looks like it's coming from a compiled CSS file from within your application. Perhaps from a plugin. Changing the name of the "menu" class you are using should resolve the issue.

Visual for you - http://i.imgur.com/d533SQD.png

Simplest/cleanest way to implement a singleton in JavaScript

I think I have found the cleanest way to program in JavaScript, but you'll need some imagination. I got this idea from a working technique in the book JavaScript: The Good Parts.

Instead of using the new keyword, you could create a class like this:

function Class()
{
    var obj = {}; // Could also be used for inheritance if you don't start with an empty object.

    var privateVar;
    obj.publicVar;

    obj.publicMethod = publicMethod;
    function publicMethod(){}

    function privateMethod(){}

    return obj;
}

You can instantiate the above object by saying:

var objInst = Class(); // !!! NO NEW KEYWORD

Now with this work method in mind, you could create a singleton like this:

ClassSingleton = function()
{
    var instance = null;

    function Class() // This is the class like the above one
    {
        var obj = {};
        return obj;
    }

    function getInstance()
    {
        if( !instance )
            instance = Class(); // Again no 'new' keyword;

        return instance;
    }

    return { getInstance : getInstance };
}();

Now you can get your instance by calling

var obj = ClassSingleton.getInstance();

I think this is the neatest way as the complete "Class" is not even accessible.

jQuery - Getting form values for ajax POST

var username = $('#username').val();
var email= $('#email').val();
var password= $('#password').val();

Error: "setFile(null,false) call failed" when using log4j

i just add write permission to "logs" folder and it works for me

add write permission

How to get request URL in Spring Boot RestController

Allows getting any URL on your system, not just a current one.

import org.springframework.hateoas.mvc.ControllerLinkBuilder
...
ControllerLinkBuilder linkBuilder = ControllerLinkBuilder.linkTo(methodOn(YourController.class).getSomeEntityMethod(parameterId, parameterTwoId))

URI methodUri = linkBuilder.Uri()
String methodUrl = methodUri.getPath()

How to install Jdk in centos

I advise you to use the same JDK as you may use with Windows: the Oracle one.

http://www.oracle.com/technetwork/java/javase/downloads/index.html
Go to the Java SE 7u67 section and click on JDK7 Download button on the right.

On the new page select the option "(¤) Accept License Agreement"
Then click on jdk-7u67-linux-x64.rpm

On your CentOS, as root, run:

$ rpm -Uvh jdk-7u67-linux-x64.rpm
$ alternatives --install /usr/bin/java java /usr/java/latest/bin/java 2

You may already have a Java 5 installed on your box... before installing the downloaded rpm remove previous Java by running this command yum remove java

How can I generate random number in specific range in Android?

Random r = new Random();
int i1 = r.nextInt(80 - 65) + 65;

This gives a random integer between 65 (inclusive) and 80 (exclusive), one of 65,66,...,78,79.

How to easily initialize a list of Tuples?

    var colors = new[]
    {
        new { value = Color.White, name = "White" },
        new { value = Color.Silver, name = "Silver" },
        new { value = Color.Gray, name = "Gray" },
        new { value = Color.Black, name = "Black" },
        new { value = Color.Red, name = "Red" },
        new { value = Color.Maroon, name = "Maroon" },
        new { value = Color.Yellow, name = "Yellow" },
        new { value = Color.Olive, name = "Olive" },
        new { value = Color.Lime, name = "Lime" },
        new { value = Color.Green, name = "Green" },
        new { value = Color.Aqua, name = "Aqua" },
        new { value = Color.Teal, name = "Teal" },
        new { value = Color.Blue, name = "Blue" },
        new { value = Color.Navy, name = "Navy" },
        new { value = Color.Pink, name = "Pink" },
        new { value = Color.Fuchsia, name = "Fuchsia" },
        new { value = Color.Purple, name = "Purple" }
    };
    foreach (var color in colors)
    {
        stackLayout.Children.Add(
            new Label
            {
                Text = color.name,
                TextColor = color.value,
            });
        FontSize = Device.GetNamedSize(NamedSize.Large, typeof(Label))
    }

this is a Tuple<Color, string>

How to use global variables in React Native?

The way you should be doing it in React Native (as I understand it), is by saving your 'global' variable in your index.js, for example. From there you can then pass it down using props.

Example:

    class MainComponent extends Component {

        componentDidMount() {
            //Define some variable in your component
            this.variable = "What's up, I'm a variable";
        }
        ...
        render () {
            <Navigator
                renderScene={(() => {
                    return(
                        <SceneComponent
                                //Pass the variable you want to be global through here
                                myPassedVariable={this.variable}/>
                    );
                })}/>
        }
    }


    class SceneComponent extends Component {

        render() {
            return(
                <Text>{this.props.myPassedVariable}</Text>
            );
        }

    }

How to get current class name including package name in Java?

The fully-qualified name is opbtained as follows:

String fqn = YourClass.class.getName();

But you need to read a classpath resource. So use

InputStream in = YourClass.getResourceAsStream("resource.txt");

Fastest way to compute entropy in Python

This method extends the other solutions by allowing for binning. For example, bin=None (default) won't bin x and will compute an empirical probability for each element of x, while bin=256 chunks x into 256 bins before computing the empirical probabilities.

import numpy as np

def entropy(x, bins=None):
    N   = x.shape[0]
    if bins is None:
        counts = np.bincount(x)
    else:
        counts = np.histogram(x, bins=bins)[0] # 0th idx is counts
    p   = counts[np.nonzero(counts)]/N # avoids log(0)
    H   = -np.dot( p, np.log2(p) )
    return H 

How to Execute SQL Server Stored Procedure in SQL Developer?

EXEC proc_name @paramValue1 = 0, @paramValue2 = 'some text';
GO

If the Stored Procedure objective is to perform an INSERT on a table that has an Identity field declared, then the field, in this scenario @paramValue1, should be declared and just pass the value 0, because it will be auto-increment.

How to ALTER multiple columns at once in SQL Server

If you do the changes in management studio and generate scripts it makes a new table and inserts the old data into that with the changed data types. Here is a small example changing two column’s data types

/*
   12 August 201008:30:39
   User: 
   Server: CLPPRGRTEL01\TELSQLEXPRESS
   Database: Tracker_3
   Application: 
*/

/* To prevent any potential data loss issues, you should review this script in detail before running it outside the context of the database designer.*/
BEGIN TRANSACTION
SET QUOTED_IDENTIFIER ON
SET ARITHABORT ON
SET NUMERIC_ROUNDABORT OFF
SET CONCAT_NULL_YIELDS_NULL ON
SET ANSI_NULLS ON
SET ANSI_PADDING ON
SET ANSI_WARNINGS ON
COMMIT
BEGIN TRANSACTION
GO
ALTER TABLE dbo.tblDiary
    DROP CONSTRAINT FK_tblDiary_tblDiary_events
GO
ALTER TABLE dbo.tblDiary_events SET (LOCK_ESCALATION = TABLE)
GO
COMMIT
BEGIN TRANSACTION
GO
CREATE TABLE dbo.Tmp_tblDiary
    (
    Diary_ID int NOT NULL IDENTITY (1, 1),
    Date date NOT NULL,
    Diary_event_type_ID int NOT NULL,
    Notes varchar(MAX) NULL,
    Expected_call_volumes real NULL,
    Expected_duration real NULL,
    Skill_affected smallint NULL
    )  ON T3_Data_2
     TEXTIMAGE_ON T3_Data_2
GO
ALTER TABLE dbo.Tmp_tblDiary SET (LOCK_ESCALATION = TABLE)
GO
SET IDENTITY_INSERT dbo.Tmp_tblDiary ON
GO
IF EXISTS(SELECT * FROM dbo.tblDiary)
     EXEC('INSERT INTO dbo.Tmp_tblDiary (Diary_ID, Date, Diary_event_type_ID, Notes, Expected_call_volumes, Expected_duration, Skill_affected)
        SELECT Diary_ID, Date, Diary_event_type_ID, CONVERT(varchar(MAX), Notes), Expected_call_volumes, Expected_duration, CONVERT(smallint, Skill_affected) FROM dbo.tblDiary WITH (HOLDLOCK TABLOCKX)')
GO
SET IDENTITY_INSERT dbo.Tmp_tblDiary OFF
GO
DROP TABLE dbo.tblDiary
GO
EXECUTE sp_rename N'dbo.Tmp_tblDiary', N'tblDiary', 'OBJECT' 
GO
ALTER TABLE dbo.tblDiary ADD CONSTRAINT
    PK_tblDiary PRIMARY KEY NONCLUSTERED 
    (
    Diary_ID
    ) WITH( PAD_INDEX = OFF, FILLFACTOR = 86, STATISTICS_NORECOMPUTE = OFF, IGNORE_DUP_KEY = OFF, ALLOW_ROW_LOCKS = ON, ALLOW_PAGE_LOCKS = ON) ON T3_Data_2

GO
CREATE UNIQUE CLUSTERED INDEX tblDiary_ID ON dbo.tblDiary
    (
    Diary_ID
    ) WITH( PAD_INDEX = OFF, FILLFACTOR = 86, STATISTICS_NORECOMPUTE = OFF, IGNORE_DUP_KEY = OFF, ALLOW_ROW_LOCKS = ON, ALLOW_PAGE_LOCKS = ON) ON T3_Data_2
GO
CREATE NONCLUSTERED INDEX tblDiary_date ON dbo.tblDiary
    (
    Date
    ) WITH( PAD_INDEX = OFF, FILLFACTOR = 86, STATISTICS_NORECOMPUTE = OFF, IGNORE_DUP_KEY = OFF, ALLOW_ROW_LOCKS = ON, ALLOW_PAGE_LOCKS = ON) ON T3_Data_2
GO
ALTER TABLE dbo.tblDiary WITH NOCHECK ADD CONSTRAINT
    FK_tblDiary_tblDiary_events FOREIGN KEY
    (
    Diary_event_type_ID
    ) REFERENCES dbo.tblDiary_events
    (
    Diary_event_ID
    ) ON UPDATE  CASCADE 
     ON DELETE  CASCADE 

GO
COMMIT

Failed to load c++ bson extension

Followint @user1548357 I decided to change the module file itself. So as to avoid the problems pointed out by the valid comments below I included my changes in a postinstall script so that I can set it and forget it and be assured that it will run when my modules are installed.

// package.json
"scripts": {
    // other scripts
    "postinstall": "node ./bson.fix.js"
},

and the script is:

// bson.fix.js
var fs = require('fs');
var file = './node_modules/bson/ext/index.js'
fs.readFile(file, 'utf8', function (err,data) {
  if (err) {
    return console.log(err);
  }
  var result = data.replace(/\.\.\/build\/Release\/bson/g, 'bson');
  fs.writeFile(file, result, 'utf8', function (err) {
     if (err) return console.log(err);
     console.log('Fixed bson module so as to use JS version');
  });
});

How to apply a CSS filter to a background image

Of course, this is not a CSS-solution, but you can use the CDN Proton with filter:

body {
    background: url('https://i0.wp.com/IMAGEURL?w=600&filter=blurgaussian&smooth=1');
}

It is from https://developer.wordpress.com/docs/photon/api/#filter

Placing an image to the top right corner - CSS

While looking at the same problem, I found an example

<style type="text/css">
#topright {
    position: absolute;
    right: 0;
    top: 0;
    display: block;
    height: 125px;
    width: 125px;
    background: url(TRbanner.gif) no-repeat;
    text-indent: -999em;
    text-decoration: none;
}
</style>

<a id="topright" href="#" title="TopRight">Top Right Link Text</a>

The trick here is to create a small, (I used GIMP) a PNG (or GIF) that has a transparent background, (and then just delete the opposite bottom corner.)

what's the default value of char?

Default value of Character is Character.MIN_VALUE which internally represented as MIN_VALUE = '\u0000'

Additionally, you can check if the character field contains default value as

Character DEFAULT_CHAR = new Character(Character.MIN_VALUE);
if (DEFAULT_CHAR.compareTo((Character) value) == 0)
{

}

Referenced Project gets "lost" at Compile Time

Check your build types of each project under project properties - I bet one or the other will be set to build against .NET XX - Client Profile.

With inconsistent versions, specifically with one being Client Profile and the other not, then it works at design time but fails at compile time. A real gotcha.

There is something funny going on in Visual Studio 2010 for me, which keeps setting projects seemingly randomly to Client Profile, sometimes when I create a project, and sometimes a few days later. Probably some keyboard shortcut I'm accidentally hitting...

How to rename uploaded file before saving it into a directory?

You guess correctly. Read the manual page for move_uploaded_file. Set the second parameter to whereever your want to save the file.

If it doesn't work, there is something wrong with your $fileName. Please post your most recent code.

How to set an HTTP proxy in Python 2.7?

For installing pip with get-pip.py behind a proxy I went with the steps below. My server was even behind a jump server.

From the jump server:

ssh -R 18080:proxy-server:8080 my-python-server

On the "python-server"

export https_proxy=https://localhost:18080 ; export http_proxy=http://localhost:18080 ; export ftp_proxy=$http_proxy
python get-pip.py

Success.

Switch android x86 screen resolution

To change the Android-x86 screen resolution on VirtualBox you need to:

  1. Add custom screen resolution:
    Android <6.0:

    VBoxManage setextradata "VM_NAME_HERE" "CustomVideoMode1" "320x480x16"
    

    Android >=6.0:

    VBoxManage setextradata "VM_NAME_HERE" "CustomVideoMode1" "320x480x32"
    
  2. Figure out what is the ‘hex’-value for your VideoMode:
    2.1. Start the VM
    2.2. In GRUB menu enter a (Android >=6.0: e)
    2.3. In the next screen append vga=ask and press Enter
    2.4. Find your resolution and write down/remember the 'hex'-value for Mode column

  3. Translate the value to decimal notation (for example 360 hex is 864 in decimal).

  4. Go to menu.lst and modify it:
    4.1. From the GRUB menu select Debug Mode
    4.2. Input the following:

    mount -o remount,rw /mnt  
    cd /mnt/grub  
    vi menu.lst
    

    4.3. Add vga=864 (if your ‘hex’-value is 360). Now it should look like this:

    kernel /android-2.3-RC1/kernel quiet root=/dev/ram0 androidboot_hardware=eeepc acpi_sleep=s3_bios,s3_mode DPI=160 UVESA_MODE=320x480 SRC=/android-2.3-RC1 SDCARD=/data/sdcard.img vga=864

    4.4. Save it:

    :wq
    
  5. Unmount and reboot:

    cd /
    umount /mnt
    reboot -f
    

Hope this helps.

why windows 7 task scheduler task fails with error 2147942667

For me it was the "Start In" - I accidentally left in the '.py' at the end of the name of my program. And I forgot to capitalize the name of the folder it was in ('Apps').

How do I get the current date and time in PHP?

Set your time zone:

date_default_timezone_set('Asia/Calcutta');

Then call the date functions

$date = date('Y-m-d H:i:s');

Import a file from a subdirectory?

Take a look at the Packages documentation (Section 6.4) here: http://docs.python.org/tutorial/modules.html

In short, you need to put a blank file named

__init__.py

in the "lib" directory.

How to pass argument to Makefile from command line?

Much easier aproach. Consider a task:

provision:
        ansible-playbook -vvvv \
        -i .vagrant/provisioners/ansible/inventory/vagrant_ansible_inventory \
        --private-key=.vagrant/machines/default/virtualbox/private_key \
        --start-at-task="$(AT)" \
        -u vagrant playbook.yml

Now when I want to call it I just run something like:

AT="build assets" make provision

or just:

make provision in this case AT is an empty string

How to convert a char to a String?

  char vIn = 'A';
  String vOut = Character.toString(vIn);

For these types of conversion, I have site bookmarked called https://www.converttypes.com/ It helps me quickly get the conversion code for most of the languages I use.

How to get the Facebook user id using the access token

You just have to hit another Graph API:

https://graph.facebook.com/me?access_token={access-token}

It will give your e-mail Id and user Id (for Facebook) also.

POST request with a simple string in body with Alamofire

I modified @Silmaril's answer to extend Alamofire's Manager. This solution uses EVReflection to serialize an object directly:

//Extend Alamofire so it can do POSTs with a JSON body from passed object
extension Alamofire.Manager {
    public class func request(
        method: Alamofire.Method,
        _ URLString: URLStringConvertible,
          bodyObject: EVObject)
        -> Request
    {
        return Manager.sharedInstance.request(
            method,
            URLString,
            parameters: [:],
            encoding: .Custom({ (convertible, params) in
                let mutableRequest = convertible.URLRequest.copy() as! NSMutableURLRequest
                mutableRequest.HTTPBody = bodyObject.toJsonString().dataUsingEncoding(NSUTF8StringEncoding, allowLossyConversion: false)
                return (mutableRequest, nil)
            })
        )
    }
}

Then you can use it like this:

Alamofire.Manager.request(.POST, endpointUrlString, bodyObject: myObjectToPost)

Editing the date formatting of x-axis tick labels in matplotlib

From the package matplotlib.dates as shown in this example the date format can be applied to the axis label and ticks for plot.

Below I have given an example for labeling axis ticks for multiplots

import matplotlib.pyplot as plt
import matplotlib.dates as mdates
import pandas as pd

df = pd.read_csv('US_temp.csv')
plt.plot(df['Date'],df_f['MINT'],label='Min Temp.')
plt.plot(df['Date'],df_f['MAXT'],label='Max Temp.')
plt.legend()
####### Use the below functions #######
dtFmt = mdates.DateFormatter('%b') # define the formatting
plt.gca().xaxis.set_major_formatter(dtFmt) # apply the format to the desired axis
plt.show()

As simple as that

align textbox and text/labels in html?

you can do a multi div layout like this

<div class="fieldcontainer">
    <div class="label"></div>
    <div class="field"></div>
</div>

where .fieldcontainer { clear: both; } .label { float: left; width: ___ } .field { float: left; }

Or, I actually prefer tables for forms like this. This is very much tabular data and it comes out very clean. Both will work though.

Select elements by attribute in CSS

It's also possible to select attributes regardless of their content, in modern browsers

with:

[data-my-attribute] {
   /* Styles */
}

[anything] {
   /* Styles */
}

For example: http://codepen.io/jasonm23/pen/fADnu

Works on a very significant percentage of browsers.

Note this can also be used in a JQuery selector, or using document.querySelector

CSS-Only Scrollable Table with fixed headers

This answer will be used as a placeholder for the not fully supported position: sticky and will be updated over time. It is currently advised to not use the native implementation of this in a production environment.

See this for the current support: https://caniuse.com/#feat=css-sticky


Use of position: sticky

An alternative answer would be using position: sticky. As described by W3C:

A stickily positioned box is positioned similarly to a relatively positioned box, but the offset is computed with reference to the nearest ancestor with a scrolling box, or the viewport if no ancestor has a scrolling box.

This described exactly the behavior of a relative static header. It would be easy to assign this to the <thead> or the first <tr> HTML-tag, as this should be supported according to W3C. However, both Chrome, IE and Edge have problems assigning a sticky position property to these tags. There also seems to be no priority in solving this at the moment.

What does seem to work for a table element is assigning the sticky property to a table-cell. In this case the <th> cells.

Because a table is not a block-element that respects the static size you assign to it, it is best to use a wrapper element to define the scroll-overflow.

The code

_x000D_
_x000D_
div {_x000D_
  display: inline-block;_x000D_
  height: 150px;_x000D_
  overflow: auto_x000D_
}_x000D_
_x000D_
table th {_x000D_
  position: -webkit-sticky;_x000D_
  position: sticky;_x000D_
  top: 0;_x000D_
}_x000D_
_x000D_
_x000D_
/* == Just general styling, not relevant :) == */_x000D_
_x000D_
table {_x000D_
  border-collapse: collapse;_x000D_
}_x000D_
_x000D_
th {_x000D_
  background-color: #1976D2;_x000D_
  color: #fff;_x000D_
}_x000D_
_x000D_
th,_x000D_
td {_x000D_
  padding: 1em .5em;_x000D_
}_x000D_
_x000D_
table tr {_x000D_
  color: #212121;_x000D_
}_x000D_
_x000D_
table tr:nth-child(odd) {_x000D_
  background-color: #BBDEFB;_x000D_
}
_x000D_
<div>_x000D_
  <table border="0">_x000D_
    <thead>_x000D_
      <tr>_x000D_
        <th>head1</th>_x000D_
        <th>head2</th>_x000D_
        <th>head3</th>_x000D_
        <th>head4</th>_x000D_
      </tr>_x000D_
    </thead>_x000D_
    <tr>_x000D_
      <td>row 1, cell 1</td>_x000D_
      <td>row 1, cell 2</td>_x000D_
      <td>row 1, cell 2</td>_x000D_
      <td>row 1, cell 2</td>_x000D_
    </tr>_x000D_
    <tr>_x000D_
      <td>row 2, cell 1</td>_x000D_
      <td>row 2, cell 2</td>_x000D_
      <td>row 1, cell 2</td>_x000D_
      <td>row 1, cell 2</td>_x000D_
    </tr>_x000D_
    <tr>_x000D_
      <td>row 2, cell 1</td>_x000D_
      <td>row 2, cell 2</td>_x000D_
      <td>row 1, cell 2</td>_x000D_
      <td>row 1, cell 2</td>_x000D_
    </tr>_x000D_
    <tr>_x000D_
      <td>row 2, cell 1</td>_x000D_
      <td>row 2, cell 2</td>_x000D_
      <td>row 1, cell 2</td>_x000D_
      <td>row 1, cell 2</td>_x000D_
    </tr>_x000D_
    <tr>_x000D_
      <td>row 2, cell 1</td>_x000D_
      <td>row 2, cell 2</td>_x000D_
      <td>row 1, cell 2</td>_x000D_
      <td>row 1, cell 2</td>_x000D_
    </tr>_x000D_
  </table>_x000D_
</div>
_x000D_
_x000D_
_x000D_

In this example I use a simple <div> wrapper to define the scroll-overflow done with a static height of 150px. This can of course be any size. Now that the scrolling box has been defined, the sticky <th> elements will corespondent "to the nearest ancestor with a scrolling box", which is the div-wrapper.


Use of a position: sticky polyfill

Non-supported devices can make use of a polyfill, which implements the behavior through code. An example is stickybits, which resembles the same behavior as the browser's implemented position: sticky.

Example with polyfill: http://jsfiddle.net/7UZA4/6957/

Get root view from current activity

if you are in a activity, assume there is only one root view,you can get it like this.

ViewGroup viewGroup = (ViewGroup) ((ViewGroup) this
        .findViewById(android.R.id.content)).getChildAt(0);

you can then cast it to your real class

or you could using

getWindow().getDecorView();

notice this will include the actionbar view, your view is below the actionbar view

Why I'm getting 'Non-static method should not be called statically' when invoking a method in a Eloquent model?

Just in case this helps someone, I was getting this error because I completely missed the stated fact that the scope prefix must not be used when calling a local scope. So if you defined a local scope in your model like this:

public function scopeRecentFirst($query)
{
    return $query->orderBy('updated_at', 'desc');
}

You should call it like:

$CurrentUsers = \App\Models\Users::recentFirst()->get();

Note that the prefix scope is not present in the call.

How to get the dimensions of a tensor (in TensorFlow) at graph construction time?

I see most people confused about tf.shape(tensor) and tensor.get_shape() Let's make it clear:

  1. tf.shape

tf.shape is used for dynamic shape. If your tensor's shape is changable, use it. An example: a input is an image with changable width and height, we want resize it to half of its size, then we can write something like:
new_height = tf.shape(image)[0] / 2

  1. tensor.get_shape

tensor.get_shape is used for fixed shapes, which means the tensor's shape can be deduced in the graph.

Conclusion: tf.shape can be used almost anywhere, but t.get_shape only for shapes can be deduced from graph.

Easiest way to copy a table from one database to another?

it's worked good for me

CREATE TABLE dbto.table_name like dbfrom.table_name;
insert into  dbto.table_name select * from dbfrom.table_name;

How to test if a string contains one of the substrings in a list, in pandas?

Here is a one line lambda that also works:

df["TrueFalse"] = df['col1'].apply(lambda x: 1 if any(i in x for i in searchfor) else 0)

Input:

searchfor = ['og', 'at']

df = pd.DataFrame([('cat', 1000.0), ('hat', 2000000.0), ('dog', 1000.0), ('fog', 330000.0),('pet', 330000.0)], columns=['col1', 'col2'])

   col1  col2
0   cat 1000.0
1   hat 2000000.0
2   dog 1000.0
3   fog 330000.0
4   pet 330000.0

Apply Lambda:

df["TrueFalse"] = df['col1'].apply(lambda x: 1 if any(i in x for i in searchfor) else 0)

Output:

    col1    col2        TrueFalse
0   cat     1000.0      1
1   hat     2000000.0   1
2   dog     1000.0      1
3   fog     330000.0    1
4   pet     330000.0    0

What's causing my java.net.SocketException: Connection reset?

This is an old thread, but I ran into java.net.SocketException: Connection reset yesterday.

The server-side application had its throttling settings changed to allow only 1 connection at a time! Thus, sometimes calls went through and sometimes not. I solved the problem by changing the throttling settings.

select data up to a space?

select left(col, charindex(' ', col) - 1)

Can I use a min-height for table, tr or td?

In CSS 2.1, the effect of 'min-height' and 'max-height' on tables, inline tables, table cells, table rows, and row groups is undefined.

So try wrapping the content in a div, and give the div a min-height jsFiddle here

<table cellspacing="0" cellpadding="0" border="0" style="width:300px">
    <tbody>
        <tr>
            <td>
                <div style="min-height: 100px; background-color: #ccc">
                    Hello World !
                </div>
            </td>
            <td>
                <div style="min-height: 100px; background-color: #f00">
                    Good Morning !
                </div>
            </td>
        </tr>
    </tbody>
</table>

How to get back to the latest commit after checking out a previous commit?

git reflog //find the hash of the commit that you want to checkout
git checkout <commit number>>

How to clear a textbox using javascript

<input type="text" value="A new value" onfocus="javascript: if(this.value == 'A new value'){ this.value = ''; }" onblur="javascript: if(this.value==''){this.value='A new value';}" />

Turn off textarea resizing

CSS3 can solve this problem. Unfortunately it's only supported on 60% of used browsers nowadays.

For IE and iOS you can't turn off resizing but you can limit the textarea dimension by setting its width and height.

/* One can also turn on/off specific axis. Defaults to both on. */
textarea { resize:vertical; } /* none|horizontal|vertical|both */

See Demo

Neither BindingResult nor plain target object for bean name available as request attr

I worked on this same issue and I am sure I have found out the exact reason for it.

Neither BindingResult nor plain target object for bean name 'command' available as request attribute

If your successView property value (name of jsp page) is the same as your input page name, then second value of ModelAndView constructor must be match with the commandName of the input page.

E.g.

index.jsp

<html>
<body>
    <table>
        <tr><td><a href="Login.html">Login</a></td></tr>
    </table>
</body>
</html>

dispatcher-servlet.xml

<bean id="viewResolver"
    class="org.springframework.web.servlet.view.InternalResourceViewResolver">

    <property name="prefix">
        <value>/WEB-INF/jsp/</value>
    </property>
    <property name="suffix">
        <value>.jsp</value>
    </property>
</bean>
<bean id="urlMapping"
    class="org.springframework.web.servlet.handler.SimpleUrlHandlerMapping">
    <property name="urlMap">
        <map>              
            <entry key="/Login.html">
                <ref bean="userController"/>
            </entry>
        </map>          
    </property>             
</bean>     
 <bean id="userController" class="controller.AddCountryFormController">     
       <property name="commandName"><value>country</value></property>
       <property name="commandClass"><value>controller.Country</value></property>        
       <property name="formView"><value>countryForm</value></property>
       <property name="successView"><value>countryForm</value></property>
   </bean>      

AddCountryFormController.java

package controller;

import javax.servlet.http.*;
import org.springframework.web.servlet.ModelAndView;
import org.springframework.validation.BindException;
import org.springframework.web.servlet.mvc.SimpleFormController;


public class AddCountryFormController extends SimpleFormController
{

    public AddCountryFormController(){
        setCommandName("Country.class");
    }

    protected ModelAndView onSubmit(HttpServletRequest request,HttpServletResponse response,Object command,BindException errors){

            Country country=(Country)command;

            System.out.println("calling onsubmit method !!!!!");

        return new ModelAndView(getSuccessView(),"country",country);

    }

}

Country.java

package controller;

public class Country
{
    private String countryName;

    public void setCountryName(String value){
        countryName=value;
    }

    public String getCountryName(){
        return countryName;
    }

}

countryForm.jsp

<%@ taglib prefix="form" uri="http://www.springframework.org/tags/form" %>
<html>
<body>
    <form:form commandName="country" method="POST" >
            <table>
                    <tr><td><form:input path="countryName"/></td></tr>
                    <tr><td><input type="submit" value="Save"/></td></tr>
            </table>
    </form:form>
</body>
<html>

Input page commandName="country" ModelAndView Constructor as return new ModelAndView(getSuccessView(),"country",country); Means inputpage commandName==ModeAndView(,"commandName",)

Getting data-* attribute for onclick event for an html element

User $() to get jQuery object from your link and data() to get your values

<a id="option1" 
   data-id="10" 
   data-option="21" 
   href="#" 
   onclick="goDoSomething($(this).data('id'),$(this).data('option'));">
       Click to do something
</a>

Use -notlike to filter out multiple strings in PowerShell

Easiest way I find for multiple searches is to pipe them all (probably heavier CPU use) but for your example user:

Get-EventLog -LogName Security | where {$_.UserName -notlike "*user1"} |  where {$_.UserName -notlike "*user2"}

Adding a view controller as a subview in another view controller

A couple of observations:

  1. When you instantiate the second view controller, you are calling ViewControllerB(). If that view controller programmatically creates its view (which is unusual) that would be fine. But the presence of the IBOutlet suggests that this second view controller's scene was defined in Interface Builder, but by calling ViewControllerB(), you are not giving the storyboard a chance to instantiate that scene and hook up all the outlets. Thus the implicitly unwrapped UILabel is nil, resulting in your error message.

    Instead, you want to give your destination view controller a "storyboard id" in Interface Builder and then you can use instantiateViewController(withIdentifier:) to instantiate it (and hook up all of the IB outlets). In Swift 3:

    let controller = storyboard!.instantiateViewController(withIdentifier: "scene storyboard id")
    

    You can now access this controller's view.

  2. But if you really want to do addSubview (i.e. you're not transitioning to the next scene), then you are engaging in a practice called "view controller containment". You do not just want to simply addSubview. You want to do some additional container view controller calls, e.g.:

    let controller = storyboard!.instantiateViewController(withIdentifier: "scene storyboard id")
    addChild(controller)
    controller.view.frame = ...  // or, better, turn off `translatesAutoresizingMaskIntoConstraints` and then define constraints for this subview
    view.addSubview(controller.view)
    controller.didMove(toParent: self)
    

    For more information about why this addChild (previously called addChildViewController) and didMove(toParent:) (previously called didMove(toParentViewController:)) are necessary, see WWDC 2011 video #102 - Implementing UIViewController Containment. In short, you need to ensure that your view controller hierarchy stays in sync with your view hierarchy, and these calls to addChild and didMove(toParent:) ensure this is the case.

    Also see Creating Custom Container View Controllers in the View Controller Programming Guide.


By the way, the above illustrates how to do this programmatically. It is actually much easier if you use the "container view" in Interface Builder.

enter image description here

Then you don't have to worry about any of these containment-related calls, and Interface Builder will take care of it for you.

For Swift 2 implementation, see previous revision of this answer.

How to select unique records by SQL

I find that if I can't use DISTINCT for any reason, then GROUP BY will work.

How can I drop a table if there is a foreign key constraint in SQL Server?

To drop a table if there is a foreign key constraint in MySQL Server?

Run the sql query:

SET FOREIGN_KEY_CHECKS = 0; DROP TABLE table_name

Hope it helps!

How do I share variables between different .c files?

In 99.9% of all cases it is bad program design to share non-constant, global variables between files. There are very few cases when you actually need to do this: they are so rare that I cannot come up with any valid cases. Declarations of hardware registers perhaps.

In most of the cases, you should either use (possibly inlined) setter/getter functions ("public"), static variables at file scope ("private"), or incomplete type implementations ("private") instead.

In those few rare cases when you need to share a variable between files, do like this:

// file.h
extern int my_var;

// file.c
#include "file.h"
int my_var = something;

// main.c
#include "file.h"
use(my_var);

Never put any form of variable definition in a h-file.

Google Chrome forcing download of "f.txt" file

Seems related to https://groups.google.com/forum/#!msg/google-caja-discuss/ite6K5c8mqs/Ayqw72XJ9G8J.

The so-called "Rosetta Flash" vulnerability is that allowing arbitrary yet identifier-like text at the beginning of a JSONP response is sufficient for it to be interpreted as a Flash file executing in that origin. See for more information: http://miki.it/blog/2014/7/8/abusing-jsonp-with-rosetta-flash/

JSONP responses from the proxy servlet now: * are prefixed with "/**/", which still allows them to execute as JSONP but removes requester control over the first bytes of the response. * have the response header Content-Disposition: attachment.

jQuery get value of selected radio button

You can get the value of selected radio button by Id using this in javascript/jQuery.

$("#InvCopyRadio:checked").val();

I hope this will help.

Removing Duplicate Values from ArrayList

public static List<String> removeDuplicateElements(List<String> array){
    List<String> temp = new ArrayList<String>();
    List<Integer> count = new ArrayList<Integer>();
    for (int i=0; i<array.size()-2; i++){
        for (int j=i+1;j<array.size()-1;j++)
            {
                if (array.get(i).compareTo(array.get(j))==0) {
                    count.add(i);
                    int kk = i;
                }
            }
        }
        for (int i = count.size()+1;i>0;i--) {
            array.remove(i);
        }
        return array;
    }
}

Google Play Services GCM 9.2.0 asks to "update" back to 9.0.0

open app/build.gradle from your app-module and rewrite below line after dependencies block. This allows the plugin to determine what version of Play services you are using

apply plugin: 'com.google.gms.google-services'

I got this idea from here. In this tutorial second point is saying that above plugin line be at the bottom of your app/build.gradle file so that no dependency collisions are introduced. Hope it will help you out.

MySQL Install: ERROR: Failed to build gem native extension

I had also forgotten to actually install MySQL in the first place. Following this guide helped a lot.

http://www.djangoapp.com/blog/2011/07/24/installation-of-mysql-server-on-mac-os-x-lion/

As well as adding these lines to my .profile:

export PATH="/usr/local/mysql/bin:$PATH"
alias mysql=/usr/local/mysql/bin/mysql
alias mysqladmin=/usr/local/mysql/bin/mysqladmin

How can I get the first two digits of a number?

Comparing the O(n) time solution with the "constant time" O(1) solution provided in other answers goes to show that if the O(n) algorithm is fast enough, n may have to get very large before it is slower than a slow O(1).

The strings version is approx. 60% faster than the "maths" version for numbers of 20 or fewer digits. They become closer only when then number of digits approaches 200 digits

# the "maths" version
import math

def first_n_digits1(num, n):
    return num // 10 ** (int(math.log(num, 10)) - n + 1)

%timeit first_n_digits1(34523452452, 2)
1.21 µs ± 75 ns per loop (mean ± std. dev. of 7 runs, 1000000 loops each)

%timeit first_n_digits1(34523452452, 8)
1.24 µs ± 47.5 ns per loop (mean ± std. dev. of 7 runs, 1000000 loops each)

# 22 digits
%timeit first_n_digits1(3423234239472523452452, 2)
1.33 µs ± 59.4 ns per loop (mean ± std. dev. of 7 runs, 1000000 loops each)

%timeit first_n_digits1(3423234239472523452452, 15)
1.23 µs ± 61.2 ns per loop (mean ± std. dev. of 7 runs, 1000000 loops each)

# 196 digits
%timeit first_n_digits1(3423234239472523409283475908723908723409872390871243908172340987123409871234012089172340987734507612340981344509873123401234670350981234098123140987314509812734091823509871345109871234098172340987125988123452452, 39)
1.86 µs ± 21.8 ns per loop (mean ± std. dev. of 7 runs, 100000 loops each)

# The "string" verions
def first_n_digits2(num, n):
    return int(str(num)[:n])

%timeit first_n_digits2(34523452452, 2)
744 ns ± 28.1 ns per loop (mean ± std. dev. of 7 runs, 1000000 loops each)

%timeit first_n_digits2(34523452452, 8)
768 ns ± 42.7 ns per loop (mean ± std. dev. of 7 runs, 1000000 loops each)

# 22 digits
%timeit first_n_digits2(3423234239472523452452, 2)
767 ns ± 33.6 ns per loop (mean ± std. dev. of 7 runs, 1000000 loops each)

%timeit first_n_digits2(3423234239472523452452, 15)
830 ns ± 55.1 ns per loop (mean ± std. dev. of 7 runs, 1000000 loops each)

# 196 digits
%timeit first_n_digits2(3423234239472523409283475908723908723409872390871243908098712340987123401208917234098773450761234098134450987312340123467035098123409812314098734091823509871345109871234098172340987125988123452452, 39)
1.87 µs ± 140 ns per loop (mean ± std. dev. of 7 runs, 100000 loops each)

How do I include a pipe | in my linux find -exec command?

the solution is easy: execute via sh

... -exec sh -c "zcat {} | agrep -dEOE 'grep' " \;

How to sort 2 dimensional array by column value?

Using the arrow function, and sorting by the second string field

_x000D_
_x000D_
var a = [[12, 'CCC'], [58, 'AAA'], [57, 'DDD'], [28, 'CCC'],[18, 'BBB']];_x000D_
a.sort((a, b) => a[1].localeCompare(b[1]));_x000D_
console.log(a)
_x000D_
_x000D_
_x000D_

How to create a drop shadow only on one side of an element?

It's always better to read the specs. There is no box-shadow-bottom property, and as Lea points out you should always place the un-prefixed property at the bottom, after the prefixed ones.

So it's:

_x000D_
_x000D_
.shadow {_x000D_
  -webkit-box-shadow: 0px 2px 4px #000000;_x000D_
  -moz-box-shadow: 0px 2px 4px #000000;_x000D_
  box-shadow: 0px 2px 4px #000000;_x000D_
}
_x000D_
<div class="shadow">Some content</div>
_x000D_
_x000D_
_x000D_

Spaces cause split in path with PowerShell

For any file path with space, simply put them in double quotations will work in Windows Powershell. For example, if you want to go to Program Files directory, instead of use

PS C:\> cd Program Files

which will induce error, simply use the following will solve the problem:

PS C:\> cd "Program Files"

Reading/writing an INI file

If you only need read access and not write access and you are using the Microsoft.Extensions.Confiuration (comes bundled in by default with ASP.NET Core but works with regular programs too) you can use the NuGet package Microsoft.Extensions.Configuration.Ini to import ini files in to your configuration settings.

public Startup(IHostingEnvironment env)
{
    var builder = new ConfigurationBuilder()
        .SetBasePath(env.ContentRootPath)
        .AddIniFile("SomeConfig.ini", optional: false);
    Configuration = builder.Build();
}

Npm install failed with "cannot run in wd"

I fixed this by changing the ownership of /usr/local and ~/Users/user-name like so:

sudo chown -R my_name /usr/local

This allowed me to do everything without sudo

IIS7 folder permissions for web application

If it's any help to anyone, give permission to "IIS_IUSRS" group.

Note that if you can't find "IIS_IUSRS", try prepending it with your server's name, like "MySexyServer\IIS_IUSRS".

Why ModelState.IsValid always return false in mvc

"ModelState.IsValid" tells you that the model is consumed by the view (i.e. PaymentAdviceEntity) is satisfy all types of validation or not specified in the model properties by DataAnotation.

In this code the view does not bind any model properties. So if you put any DataAnotations or validation in model (i.e. PaymentAdviceEntity). then the validations are not satisfy. say if any properties in model is Name which makes required in model.Then the value of the property remains blank after post.So the model is not valid (i.e. ModelState.IsValid returns false). You need to remove the model level validations.

How to start Apache and MySQL automatically when Windows 8 comes up

You can do it via cmd.

For Apache

Open cmd in administrator mode. Change directory to C:/xampp/apache/bin. Run the command as httpd.exe -k install. Your Apache server service will be installed. You can start it from services.

For MySQL

Change directory to C:/xampp/mysql/bin. Run the command as mysqld --install. Your MySQL service will be installed. You can start it from services.

Note: Make sure the selected Apache and MySQL services are set to start automatically.

You're done. There isn't any need to launch the XAMPP control panel

UnicodeEncodeError: 'ascii' codec can't encode character at special name

You really want to do this

flog.write("\nCompany Name: "+ pCompanyName.encode('utf-8'))

This is the "encode late" strategy described in this unicode presentation (slides 32 through 35).

document .click function for touch device

To apply it everywhere, you could do something like

$('body').on('click', function() {
   if($('.children').is(':visible')) {
      $('ul.children').slideUp('slow');
   }
});

Should I use Python 32bit or Python 64bit

You do not need to use 64bit since windows will emulate 32bit programs using wow64. But using the native version (64bit) will give you more performance.

Bundler: Command not found

I did this (Ubuntu latest as of March 2013 [ I think :) ]):

sudo gem install bundler

Credit goes to Ray Baxter.

If you need gem, I installed Ruby this way (though this is chronically taxing):

mkdir /tmp/ruby && cd /tmp/ruby
wget http://ftp.ruby-lang.org/pub/ruby/1.9/ruby-1.9.3-p327.tar.gz
tar xfvz ruby-1.9.3-p327.tar.gz
cd ruby-1.9.3-p327
./configure
make
sudo make install

JavaScript before leaving the page

In order to have a popop with Chrome 14+, you need to do the following :

jQuery(window).bind('beforeunload', function(){
    return 'my text';
});

The user will be asked if he want to stay or leave.

How to get post slug from post in WordPress?

If you want to get slug of the post from the loop then use:

global $post;
echo $post->post_name;

If you want to get slug of the post outside the loop then use:

$post_id = 45; //specify post id here
$post = get_post($post_id); 
$slug = $post->post_name;

In C/C++ what's the simplest way to reverse the order of bits in a byte?

You may be interested in std::vector<bool> (that is bit-packed) and std::bitset

It should be the simplest as requested.

#include <iostream>
#include <bitset>
using namespace std;
int main() {
  bitset<8> bs = 5;
  bitset<8> rev;
  for(int ii=0; ii!= bs.size(); ++ii)
    rev[bs.size()-ii-1] = bs[ii];
  cerr << bs << " " << rev << endl;
}

Other options may be faster.

EDIT: I owe you a solution using std::vector<bool>

#include <algorithm>
#include <iterator>
#include <iostream>
#include <vector>
using namespace std;
int main() {
  vector<bool> b{0,0,0,0,0,1,0,1};
  reverse(b.begin(), b.end());
  copy(b.begin(), b.end(), ostream_iterator<int>(cerr));
  cerr << endl;
}

The second example requires c++0x extension (to initialize the array with {...}). The advantage of using a bitset or a std::vector<bool> (or a boost::dynamic_bitset) is that you are not limited to bytes or words but can reverse an arbitrary number of bits.

HTH

How to delete a cookie?

Try this:

function delete_cookie( name, path, domain ) {
  if( get_cookie( name ) ) {
    document.cookie = name + "=" +
      ((path) ? ";path="+path:"")+
      ((domain)?";domain="+domain:"") +
      ";expires=Thu, 01 Jan 1970 00:00:01 GMT";
  }
}

You can define get_cookie() like this:

function get_cookie(name){
    return document.cookie.split(';').some(c => {
        return c.trim().startsWith(name + '=');
    });
}

Communication between tabs or windows

I wrote an article on this on my blog: http://www.ebenmonney.com/blog/how-to-implement-remember-me-functionality-using-token-based-authentication-and-localstorage-in-a-web-application .

Using a library I created storageManager you can achieve this as follows:

storageManager.savePermanentData('data', 'key'): //saves permanent data
storageManager.saveSyncedSessionData('data', 'key'); //saves session data to all opened tabs
storageManager.saveSessionData('data', 'key'); //saves session data to current tab only
storageManager.getData('key'); //retrieves data

There are other convenient methods as well to handle other scenarios as well