Programs & Examples On #Quickgraph

QuickGraph is an open source generic graph library .NET. It handles both directed and undirected graphs and has algorithms for traversing and searching the graphs.

Dialog to pick image from gallery or from camera

You can implement this code to select image from gallery or camera :-

private ImageView imageview;
private Button btnSelectImage;
private Bitmap bitmap;
private File destination = null;
private InputStream inputStreamImg;
private String imgPath = null;
private final int PICK_IMAGE_CAMERA = 1, PICK_IMAGE_GALLERY = 2;

Now on button click event, you can able to call your method of select Image. This is inside activity's onCreate.

imageview = (ImageView) findViewById(R.id.imageview);
btnSelectImage = (Button) findViewById(R.id.btnSelectImage);

//OnbtnSelectImage click event...
btnSelectImage.setOnClickListener(new View.OnClickListener() {
        @Override
        public void onClick(View v) {
            selectImage();
        }
    });

Outside of your activity's oncreate.

// Select image from camera and gallery
private void selectImage() {
    try {
        PackageManager pm = getPackageManager();
        int hasPerm = pm.checkPermission(Manifest.permission.CAMERA, getPackageName());
        if (hasPerm == PackageManager.PERMISSION_GRANTED) {
            final CharSequence[] options = {"Take Photo", "Choose From Gallery","Cancel"};
            android.support.v7.app.AlertDialog.Builder builder = new android.support.v7.app.AlertDialog.Builder(activity);
            builder.setTitle("Select Option");
            builder.setItems(options, new DialogInterface.OnClickListener() {
                @Override
                public void onClick(DialogInterface dialog, int item) {
                    if (options[item].equals("Take Photo")) {
                        dialog.dismiss();
                        Intent intent = new Intent(MediaStore.ACTION_IMAGE_CAPTURE);
                        startActivityForResult(intent, PICK_IMAGE_CAMERA);
                    } else if (options[item].equals("Choose From Gallery")) {
                        dialog.dismiss();
                        Intent pickPhoto = new Intent(Intent.ACTION_PICK, MediaStore.Images.Media.EXTERNAL_CONTENT_URI);
                        startActivityForResult(pickPhoto, PICK_IMAGE_GALLERY);
                    } else if (options[item].equals("Cancel")) {
                        dialog.dismiss();
                    }
                }
            });
            builder.show();
        } else
            Toast.makeText(this, "Camera Permission error", Toast.LENGTH_SHORT).show();
    } catch (Exception e) {
        Toast.makeText(this, "Camera Permission error", Toast.LENGTH_SHORT).show();
        e.printStackTrace();
    }
}

@Override
public void onActivityResult(int requestCode, int resultCode, Intent data) {
    super.onActivityResult(requestCode, resultCode, data);
    inputStreamImg = null;
    if (requestCode == PICK_IMAGE_CAMERA) {
        try {
            Uri selectedImage = data.getData();
            bitmap = (Bitmap) data.getExtras().get("data");
            ByteArrayOutputStream bytes = new ByteArrayOutputStream();
            bitmap.compress(Bitmap.CompressFormat.JPEG, 50, bytes);

            Log.e("Activity", "Pick from Camera::>>> ");

            String timeStamp = new SimpleDateFormat("yyyyMMdd_HHmmss", Locale.getDefault()).format(new Date());
            destination = new File(Environment.getExternalStorageDirectory() + "/" +
                    getString(R.string.app_name), "IMG_" + timeStamp + ".jpg");
            FileOutputStream fo;
            try {
                destination.createNewFile();
                fo = new FileOutputStream(destination);
                fo.write(bytes.toByteArray());
                fo.close();
            } catch (FileNotFoundException e) {
                e.printStackTrace();
            } catch (IOException e) {
                e.printStackTrace();
            }

            imgPath = destination.getAbsolutePath();
            imageview.setImageBitmap(bitmap);

        } catch (Exception e) {
            e.printStackTrace();
        }
    } else if (requestCode == PICK_IMAGE_GALLERY) {
        Uri selectedImage = data.getData();
        try {
            bitmap = MediaStore.Images.Media.getBitmap(this.getContentResolver(), selectedImage);
            ByteArrayOutputStream bytes = new ByteArrayOutputStream();
            bitmap.compress(Bitmap.CompressFormat.JPEG, 50, bytes);
            Log.e("Activity", "Pick from Gallery::>>> ");

            imgPath = getRealPathFromURI(selectedImage);
            destination = new File(imgPath.toString());
            imageview.setImageBitmap(bitmap);

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

public String getRealPathFromURI(Uri contentUri) {
    String[] proj = {MediaStore.Audio.Media.DATA};
    Cursor cursor = managedQuery(contentUri, proj, null, null, null);
    int column_index = cursor.getColumnIndexOrThrow(MediaStore.Audio.Media.DATA);
    cursor.moveToFirst();
    return cursor.getString(column_index);
}

Atlast, finally add the camera and write external storage permission to AndroidManifest.xml

It works for me greatly, hope it will also works for you.

Setting max width for body using Bootstrap

You don't have to modify bootstrap-responsive by removing @media (max-width:1200px) ...

My application has a max-width of 1600px. Here's how it worked for me:

  1. Create bootstrap-custom.css - As much as possible, I don't want to override my original bootstrap css.

  2. Inside bootstrap-custom.css, override the container-fluid by including this code:

Like this:

/* set a max-width for horizontal fluid layout and make it centered */
.container-fluid {
  margin-right: auto;
  margin-left: auto;
  max-width: 1600px; /* or 950px */
}

How To Convert A Number To an ASCII Character?

you can simply cast it.

char c = (char)100;

How do I print a double value with full precision using cout?

C++20 std::format

This great new C++ library feature has the advantage of not affecting the state of std::cout as std::setprecision does:

#include <format>
#include <string>

int main() {
    std::cout << std::format("{:.2} {:.3}\n", 3.1415, 3.1415);
}

Expected output:

3.14 3.145

The as mentioned at https://stackoverflow.com/a/65329803/895245 not if you don't pass the precision explicitly it prints the shortest decimal representation with a round-trip guarantee. TODO understand in more detail how it compares to: dbl::max_digits10 as shown at https://stackoverflow.com/a/554134/895245 with {:.{}}:

#include <format>
#include <limits>
#include <string>

int main() {
    std::cout << std::format("{:.{}}\n",
        3.1415926535897932384626433, dbl::max_digits10);
}

See also:

Ignore cells on Excel line graph

In Excel 2007 you have the option to show empty cells as gaps, zero or connect data points with a line (I assume it's similar for Excel 2010):

enter image description here

If none of these are optimal and you have a "chunk" of data points (or even single ones) missing, you can group-and-hide them, which will remove them from the chart.

Before hiding:

enter image description here

After hiding:

enter image description here

Integer.valueOf() vs. Integer.parseInt()

The difference between these two methods is:

  • parseXxx() returns the primitive type
  • valueOf() returns a wrapper object reference of the type.

How to draw an empty plot?

The following does not plot anything in the plot and it will remain empty.

plot(NULL, xlim=c(0,1), ylim=c(0,1), ylab="y label", xlab="x lablel")

This is useful when you want to add lines or dots afterwards within a for loop or something similar. Just remember to change the xlim and ylim values based on the data you want to plot.

As a side note: This can also be used for Boxplot, Violin plots and swarm plots. for those remember to add add = TRUE to their plotting function and also specify at = to specify on which number you want to plot them (default is x axis unless you have set horz = TRUE in these functions.

Get MAC address using shell script

Observe that the interface name and the MAC address are the first and last fields on a line with no leading whitespace.

If one of the indented lines contains inet addr: the latest interface name and MAC address should be printed.

ifconfig -a |
awk '/^[a-z]/ { iface=$1; mac=$NF; next }
    /inet addr:/ { print iface, mac }'

Note that multiple interfaces could meet your criteria. Then, the script will print multiple lines. (You can add ; exit just before the final closing brace if you always only want to print the first match.)

How do I run two commands in one line in Windows CMD?

A number of processing symbols can be used when running several commands on the same line, and may lead to processing redirection in some cases, altering output in other case, or just fail. One important case is placing on the same line commands that manipulate variables.

@echo off
setlocal enabledelayedexpansion
set count=0
set "count=1" & echo %count% !count!

0 1

As you see in the above example, when commands using variables are placed on the same line, you must use delayed expansion to update your variable values. If your variable is indexed, use CALL command with %% modifiers to update its value on the same line:

set "i=5" & set "arg!i!=MyFile!i!" & call echo path!i!=%temp%\%%arg!i!%%

path5=C:\Users\UserName\AppData\Local\Temp\MyFile5

WordPress path url in js script file

According to the Wordpress documentation, you should use wp_localize_script() in your functions.php file. This will create a Javascript Object in the header, which will be available to your scripts at runtime.

See Codex

Example:

<?php wp_localize_script('mylib', 'WPURLS', array( 'siteurl' => get_option('siteurl') )); ?>

To access this variable within in Javascript, you would simply do:

<script type="text/javascript">
    var url = WPURLS.siteurl;
</script>

Disable Laravel's Eloquent timestamps

You either have to declare public $timestamps = false; in every model, or create a BaseModel, define it there, and have all your models extend it instead of eloquent. Just bare in mind pivot tables MUST have timestamps if you're using Eloquent.

Update: Note that timestamps are no longer REQUIRED in pivot tables after Laravel v3.

Update: You can also disable timestamps by removing $table->timestamps() from your migration.

How do DATETIME values work in SQLite?

SQlite does not have a specific datetime type. You can use TEXT, REAL or INTEGER types, whichever suits your needs.

Straight from the DOCS

SQLite does not have a storage class set aside for storing dates and/or times. Instead, the built-in Date And Time Functions of SQLite are capable of storing dates and times as TEXT, REAL, or INTEGER values:

  • TEXT as ISO8601 strings ("YYYY-MM-DD HH:MM:SS.SSS").
  • REAL as Julian day numbers, the number of days since noon in Greenwich on November 24, 4714 B.C. according to the proleptic Gregorian calendar.
  • INTEGER as Unix Time, the number of seconds since 1970-01-01 00:00:00 UTC.

Applications can chose to store dates and times in any of these formats and freely convert between formats using the built-in date and time functions.

SQLite built-in Date and Time functions can be found here.

jQuery find element by data attribute value

You can also use .filter()

$('.slide-link').filter('[data-slide="0"]').addClass('active');

How do I check if an object has a specific property in JavaScript?

JavaScript is now evolving and growing it has now good and best even efficient way to check it

Here are some easy ways to check if object has a particular property:

  1. Using hasOwnProperty()
const hero = {
  name: 'Batman'
};

hero.hasOwnProperty('name');     // => true
hero.hasOwnProperty('realName'); // => false
  1. Using keyword/operator in
const hero = {
  name: 'Batman'
};

'name' in hero;     // => true
'realName' in hero; // => false
  1. Comparing with undefined keyword
const hero = {
  name: 'Batman'
};

hero.name;     // => 'Batman'
hero.realName; // => undefined

// So consider this
hero.realName == undefined // => true (which means property does not exists in object)
hero.name == undefined // => false (which means that property exists in object)

For more information, check here.

C Macro definition to determine big endian or little endian machine?

Please pay attention that most of the answers here are not portable, since compilers today will evaluate those answers in compilation time (depends on the optimization) and return a specific value based on a specific endianness, while the actual machine endianness can differ. The values on which the endianness is tested, won't never reach the system memory thus the real executed code will return the same result regardless of the actual endianness.

For example, in ARM Cortex-M3 the implemented endianness will reflect in a status bit AIRCR.ENDIANNESS and compiler cannot know this value in compile time.

Compilation output for some of the answers suggested here:

https://godbolt.org/z/GJGNE2 for this answer,

https://godbolt.org/z/Yv-pyJ for this answer, and so on.

To solve it you will need to use the volatile qualifier. Yogeesh H T's answer is the closest one for today's real life usage, but since Christoph suggests more comprehensive solution, a slight fix to his answer would make the answer complete, just add volatile to the union declaration: static const volatile union.

This would assure storing and reading from memory, which is needed to determine endianness.

Where should I put the CSS and Javascript code in an HTML webpage?

CSS includes should go in the head before any js script includes. Javascript can go anywhere, but really the function of the file could determine the location. If it builds page content put it on the head. If its used for events or tracking, you can put it before the </body>

Linking a UNC / Network drive on an html page

Setup IIS on the network server and change the path to http://server/path/to/file.txt

EDIT: Make sure you enable directory browsing in IIS

Update Fragment from ViewPager

Very simple to override the method in the fragment:

@Override

public void setUserVisibleHint(boolean isVisibleToUser) {
    super.setUserVisibleHint(isVisibleToUser);

    if(isVisibleToUser){
        actionView();
    }
    else{
        //no
    }      
}

error_reporting(E_ALL) does not produce error

you can try to put this in your php.ini:

ini_set("display_errors", "1");
error_reporting(E_ALL);

In php.ini file also you can set error_reporting();

List of Timezone IDs for use with FindTimeZoneById() in C#?

I know it's old and old question but Microsoft appears to have provided this through MSDN now.

http://msdn.microsoft.com/en-us/library/gg154758.aspx

How to set the min and max height or width of a Frame?

A workaround - at least for the minimum size: You can use grid to manage the frames contained in root and make them follow the grid size by setting sticky='nsew'. Then you can use root.grid_rowconfigure and root.grid_columnconfigure to set values for minsize like so:

from tkinter import Frame, Tk

class MyApp():
    def __init__(self):
        self.root = Tk()

        self.my_frame_red = Frame(self.root, bg='red')
        self.my_frame_red.grid(row=0, column=0, sticky='nsew')

        self.my_frame_blue = Frame(self.root, bg='blue')
        self.my_frame_blue.grid(row=0, column=1, sticky='nsew')

        self.root.grid_rowconfigure(0, minsize=200, weight=1)
        self.root.grid_columnconfigure(0, minsize=200, weight=1)
        self.root.grid_columnconfigure(1, weight=1)

        self.root.mainloop()

if __name__ == '__main__':
    app = MyApp()

But as Brian wrote (in 2010 :D) you can still resize the window to be smaller than the frame if you don't limit its minsize.

Match whitespace but not newlines

The below regex would match white spaces but not of a new line character.

(?:(?!\n)\s)

DEMO

If you want to add carriage return also then add \r with the | operator inside the negative lookahead.

(?:(?![\n\r])\s)

DEMO

Add + after the non-capturing group to match one or more white spaces.

(?:(?![\n\r])\s)+

DEMO

I don't know why you people failed to mention the POSIX character class [[:blank:]] which matches any horizontal whitespaces (spaces and tabs). This POSIX chracter class would work on BRE(Basic REgular Expressions), ERE(Extended Regular Expression), PCRE(Perl Compatible Regular Expression).

DEMO

How to create EditText with cross(x) button at end of it?

I did the UI part like below:

<RelativeLayout
    android:layout_width="fill_parent"
    android:layout_height="50dp"
    android:layout_marginTop="9dp"
    android:padding="5dp">

    <EditText
        android:id="@+id/etSearchToolbar"
        android:layout_width="fill_parent"
        android:layout_height="match_parent"
        android:textSize="13dp"
        android:padding="10dp"
        android:textColor="@android:color/darker_gray"
        android:textStyle="normal"
        android:hint="Search"
        android:imeOptions="actionSearch"
        android:inputType="text"
        android:background="@drawable/edittext_bg"
        android:maxLines="1" />

    <ImageView
        android:id="@+id/ivClearSearchText"
        android:layout_width="wrap_content"
        android:layout_height="wrap_content"
        android:layout_centerVertical="true"
        android:layout_marginRight="6dp"
        android:src="@drawable/balloon_overlay_close"
        android:layout_alignParentRight="true"
        android:layout_alignParentEnd="true" />
</RelativeLayout>

edittext_bg.xml

<?xml version="1.0" encoding="utf-8"?>
<!-- res/drawable/rounded_edittext_focused.xml -->
<shape xmlns:android="http://schemas.android.com/apk/res/android"
    android:padding="10dp"
    android:shape="rectangle" >

    <solid android:color="#FFFFFF" />

    <stroke
        android:width="1dp"
        android:color="#C9C9CE" />

    <corners
        android:bottomLeftRadius="15dp"
        android:bottomRightRadius="15dp"
        android:topLeftRadius="15dp"
        android:topRightRadius="15dp" />

</shape>

balloon_overlay_close.pngenter image description here

Cross/Clear button hide/show:

searchBox.addTextChangedListener(new TextWatcher() {
    @Override
    public void beforeTextChanged(CharSequence charSequence, int i, int i1, int i2) {}

    @Override
    public void onTextChanged(CharSequence charSequence, int i, int i1, int i2) {
        if(charSequence.length() > 0){
            clearSearch.setVisibility(View.VISIBLE);
        }else{
            clearSearch.setVisibility(View.GONE);
        }
    }

    @Override
    public void afterTextChanged(Editable editable) {}
});

Handle search stuffs (i.e when user clicks search from soft key board)

searchBox.setOnEditorActionListener(new TextView.OnEditorActionListener() {
    @Override
    public boolean onEditorAction(TextView v, int actionId, KeyEvent event) {
        if (actionId == EditorInfo.IME_ACTION_SEARCH) {
            String contents = searchBox.getText().toString().trim();
            if(contents.length() > 0){
                //do search

            }else{
                //if something to do for empty edittext
            }

            return true;
        }
        return false;
    }
});

Clear/Cross button

clearSearch.setOnClickListener(new View.OnClickListener() {
    @Override
    public void onClick(View view) {
        searchBox.setText("");
    }
});

How do I prevent site scraping?

Putting your content behind a captcha would mean that robots would find it difficult to access your content. However, humans would be inconvenienced so that may be undesirable.

How to create an AVD for Android 4.0

I had a similar problem but using IntelliJ IDEA rather than Eclipse. I already had the ARM EABI installed, but I still got the error.

For IntelliJ IDEA, it appears you also have to create an AVB first before running the emulator, so to do this you must just go into Android SDK Manager and create a new AVB. This should solve your problem... Please make sure you have followed the above answer to include the ARM before following these steps.

"No such file or directory" but it exists

I got the same error for a simple bash script that wouldn't have 32/64-bit issues. This is possibly because the script you are trying to run has an error in it. This ubuntu forum post indicates that with normal script files you can add 'sh' in front and you might get some debug output from it. e.g.

$ sudo sh arm-mingw32ce-g++

and see if you get any output.

In my case the actual problem was that the file that I was trying to execute was in Windows format rather than linux.

Pandas merge two dataframes with different columns

I had this problem today using any of concat, append or merge, and I got around it by adding a helper column sequentially numbered and then doing an outer join

helper=1
for i in df1.index:
    df1.loc[i,'helper']=helper
    helper=helper+1
for i in df2.index:
    df2.loc[i,'helper']=helper
    helper=helper+1
df1.merge(df2,on='helper',how='outer')

Reading Space separated input in python

the_string = raw_input()
name, age = the_string.split()

performing HTTP requests with cURL (using PROXY)

From man curl:

-x, --proxy <[protocol://][user:password@]proxyhost[:port]>

     Use the specified HTTP proxy. 
     If the port number is not specified, it is assumed at port 1080.

General way:

export http_proxy=http://your.proxy.server:port/

Then you can connect through proxy from (many) application.

And, as per comment below, for https:

export https_proxy=https://your.proxy.server:port/

How to return a file using Web API?

I've been wondering if there was a simple way to download a file in a more ... "generic" way. I came up with this.

It's a simple ActionResult that will allow you to download a file from a controller call that returns an IHttpActionResult. The file is stored in the byte[] Content. You can turn it into a stream if needs be.

I used this to return files stored in a database's varbinary column.

    public class FileHttpActionResult : IHttpActionResult
    {
        public HttpRequestMessage Request { get; set; }

        public string FileName { get; set; }
        public string MediaType { get; set; }
        public HttpStatusCode StatusCode { get; set; }

        public byte[] Content { get; set; }

        public Task<HttpResponseMessage> ExecuteAsync(CancellationToken cancellationToken)
        {
            HttpResponseMessage response = new HttpResponseMessage(StatusCode);

            response.StatusCode = StatusCode;
            response.Content = new StreamContent(new MemoryStream(Content));
            response.Content.Headers.ContentDisposition = new ContentDispositionHeaderValue("attachment");
            response.Content.Headers.ContentDisposition.FileName = FileName;
            response.Content.Headers.ContentType = new MediaTypeHeaderValue(MediaType);

            return Task.FromResult(response);
        }
    }

Process to convert simple Python script into Windows executable

You could create an installer for you EXE file by:
1. Press WinKey + R
2. Type "iexpress" (without quotes) into the run window
3. Complete the wizard for creating the installation program.
4. Distribute the completed EXE.

How do I vertically center an H1 in a div?

Just use padding top and bottom, it will automatically center the content vertically.

Do I need a content-type header for HTTP GET requests?

The problem with not passing over the content-type on a GET message is that sure the content-type is irrelevant because the server side determines the content anyway. The problem that I have encountered is that there are now a lot of places that set up their webservices to be smart enough to pick up the content-type that you pass and return the response in the 'type' that you request. Eg. we are currently messaging with a place that defaults to JSON, however, they have set their webservice up so that if you pass a content-type of xml they will then return xml rather than their JSON default. Which I think going forward is a great idea

Replacing a 32-bit loop counter with 64-bit introduces crazy performance deviations with _mm_popcnt_u64 on Intel CPUs

Culprit: False Data Dependency (and the compiler isn't even aware of it)

On Sandy/Ivy Bridge and Haswell processors, the instruction:

popcnt  src, dest

appears to have a false dependency on the destination register dest. Even though the instruction only writes to it, the instruction will wait until dest is ready before executing. This false dependency is (now) documented by Intel as erratum HSD146 (Haswell) and SKL029 (Skylake)

Skylake fixed this for lzcnt and tzcnt.
Cannon Lake (and Ice Lake) fixed this for popcnt.
bsf/bsr have a true output dependency: output unmodified for input=0. (But no way to take advantage of that with intrinsics - only AMD documents it and compilers don't expose it.)

(Yes, these instructions all run on the same execution unit).


This dependency doesn't just hold up the 4 popcnts from a single loop iteration. It can carry across loop iterations making it impossible for the processor to parallelize different loop iterations.

The unsigned vs. uint64_t and other tweaks don't directly affect the problem. But they influence the register allocator which assigns the registers to the variables.

In your case, the speeds are a direct result of what is stuck to the (false) dependency chain depending on what the register allocator decided to do.

  • 13 GB/s has a chain: popcnt-add-popcnt-popcnt → next iteration
  • 15 GB/s has a chain: popcnt-add-popcnt-add → next iteration
  • 20 GB/s has a chain: popcnt-popcnt → next iteration
  • 26 GB/s has a chain: popcnt-popcnt → next iteration

The difference between 20 GB/s and 26 GB/s seems to be a minor artifact of the indirect addressing. Either way, the processor starts to hit other bottlenecks once you reach this speed.


To test this, I used inline assembly to bypass the compiler and get exactly the assembly I want. I also split up the count variable to break all other dependencies that might mess with the benchmarks.

Here are the results:

Sandy Bridge Xeon @ 3.5 GHz: (full test code can be found at the bottom)

  • GCC 4.6.3: g++ popcnt.cpp -std=c++0x -O3 -save-temps -march=native
  • Ubuntu 12

Different Registers: 18.6195 GB/s

.L4:
    movq    (%rbx,%rax,8), %r8
    movq    8(%rbx,%rax,8), %r9
    movq    16(%rbx,%rax,8), %r10
    movq    24(%rbx,%rax,8), %r11
    addq    $4, %rax

    popcnt %r8, %r8
    add    %r8, %rdx
    popcnt %r9, %r9
    add    %r9, %rcx
    popcnt %r10, %r10
    add    %r10, %rdi
    popcnt %r11, %r11
    add    %r11, %rsi

    cmpq    $131072, %rax
    jne .L4

Same Register: 8.49272 GB/s

.L9:
    movq    (%rbx,%rdx,8), %r9
    movq    8(%rbx,%rdx,8), %r10
    movq    16(%rbx,%rdx,8), %r11
    movq    24(%rbx,%rdx,8), %rbp
    addq    $4, %rdx

    # This time reuse "rax" for all the popcnts.
    popcnt %r9, %rax
    add    %rax, %rcx
    popcnt %r10, %rax
    add    %rax, %rsi
    popcnt %r11, %rax
    add    %rax, %r8
    popcnt %rbp, %rax
    add    %rax, %rdi

    cmpq    $131072, %rdx
    jne .L9

Same Register with broken chain: 17.8869 GB/s

.L14:
    movq    (%rbx,%rdx,8), %r9
    movq    8(%rbx,%rdx,8), %r10
    movq    16(%rbx,%rdx,8), %r11
    movq    24(%rbx,%rdx,8), %rbp
    addq    $4, %rdx

    # Reuse "rax" for all the popcnts.
    xor    %rax, %rax    # Break the cross-iteration dependency by zeroing "rax".
    popcnt %r9, %rax
    add    %rax, %rcx
    popcnt %r10, %rax
    add    %rax, %rsi
    popcnt %r11, %rax
    add    %rax, %r8
    popcnt %rbp, %rax
    add    %rax, %rdi

    cmpq    $131072, %rdx
    jne .L14

So what went wrong with the compiler?

It seems that neither GCC nor Visual Studio are aware that popcnt has such a false dependency. Nevertheless, these false dependencies aren't uncommon. It's just a matter of whether the compiler is aware of it.

popcnt isn't exactly the most used instruction. So it's not really a surprise that a major compiler could miss something like this. There also appears to be no documentation anywhere that mentions this problem. If Intel doesn't disclose it, then nobody outside will know until someone runs into it by chance.

(Update: As of version 4.9.2, GCC is aware of this false-dependency and generates code to compensate it when optimizations are enabled. Major compilers from other vendors, including Clang, MSVC, and even Intel's own ICC are not yet aware of this microarchitectural erratum and will not emit code that compensates for it.)

Why does the CPU have such a false dependency?

We can speculate: it runs on the same execution unit as bsf / bsr which do have an output dependency. (How is POPCNT implemented in hardware?). For those instructions, Intel documents the integer result for input=0 as "undefined" (with ZF=1), but Intel hardware actually gives a stronger guarantee to avoid breaking old software: output unmodified. AMD documents this behaviour.

Presumably it was somehow inconvenient to make some uops for this execution unit dependent on the output but others not.

AMD processors do not appear to have this false dependency.


The full test code is below for reference:

#include <iostream>
#include <chrono>
#include <x86intrin.h>

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

   using namespace std;
   uint64_t size=1<<20;

   uint64_t* buffer = new uint64_t[size/8];
   char* charbuffer=reinterpret_cast<char*>(buffer);
   for (unsigned i=0;i<size;++i) charbuffer[i]=rand()%256;

   uint64_t count,duration;
   chrono::time_point<chrono::system_clock> startP,endP;
   {
      uint64_t c0 = 0;
      uint64_t c1 = 0;
      uint64_t c2 = 0;
      uint64_t c3 = 0;
      startP = chrono::system_clock::now();
      for( unsigned k = 0; k < 10000; k++){
         for (uint64_t i=0;i<size/8;i+=4) {
            uint64_t r0 = buffer[i + 0];
            uint64_t r1 = buffer[i + 1];
            uint64_t r2 = buffer[i + 2];
            uint64_t r3 = buffer[i + 3];
            __asm__(
                "popcnt %4, %4  \n\t"
                "add %4, %0     \n\t"
                "popcnt %5, %5  \n\t"
                "add %5, %1     \n\t"
                "popcnt %6, %6  \n\t"
                "add %6, %2     \n\t"
                "popcnt %7, %7  \n\t"
                "add %7, %3     \n\t"
                : "+r" (c0), "+r" (c1), "+r" (c2), "+r" (c3)
                : "r"  (r0), "r"  (r1), "r"  (r2), "r"  (r3)
            );
         }
      }
      count = c0 + c1 + c2 + c3;
      endP = chrono::system_clock::now();
      duration=chrono::duration_cast<std::chrono::nanoseconds>(endP-startP).count();
      cout << "No Chain\t" << count << '\t' << (duration/1.0E9) << " sec \t"
            << (10000.0*size)/(duration) << " GB/s" << endl;
   }
   {
      uint64_t c0 = 0;
      uint64_t c1 = 0;
      uint64_t c2 = 0;
      uint64_t c3 = 0;
      startP = chrono::system_clock::now();
      for( unsigned k = 0; k < 10000; k++){
         for (uint64_t i=0;i<size/8;i+=4) {
            uint64_t r0 = buffer[i + 0];
            uint64_t r1 = buffer[i + 1];
            uint64_t r2 = buffer[i + 2];
            uint64_t r3 = buffer[i + 3];
            __asm__(
                "popcnt %4, %%rax   \n\t"
                "add %%rax, %0      \n\t"
                "popcnt %5, %%rax   \n\t"
                "add %%rax, %1      \n\t"
                "popcnt %6, %%rax   \n\t"
                "add %%rax, %2      \n\t"
                "popcnt %7, %%rax   \n\t"
                "add %%rax, %3      \n\t"
                : "+r" (c0), "+r" (c1), "+r" (c2), "+r" (c3)
                : "r"  (r0), "r"  (r1), "r"  (r2), "r"  (r3)
                : "rax"
            );
         }
      }
      count = c0 + c1 + c2 + c3;
      endP = chrono::system_clock::now();
      duration=chrono::duration_cast<std::chrono::nanoseconds>(endP-startP).count();
      cout << "Chain 4   \t"  << count << '\t' << (duration/1.0E9) << " sec \t"
            << (10000.0*size)/(duration) << " GB/s" << endl;
   }
   {
      uint64_t c0 = 0;
      uint64_t c1 = 0;
      uint64_t c2 = 0;
      uint64_t c3 = 0;
      startP = chrono::system_clock::now();
      for( unsigned k = 0; k < 10000; k++){
         for (uint64_t i=0;i<size/8;i+=4) {
            uint64_t r0 = buffer[i + 0];
            uint64_t r1 = buffer[i + 1];
            uint64_t r2 = buffer[i + 2];
            uint64_t r3 = buffer[i + 3];
            __asm__(
                "xor %%rax, %%rax   \n\t"   // <--- Break the chain.
                "popcnt %4, %%rax   \n\t"
                "add %%rax, %0      \n\t"
                "popcnt %5, %%rax   \n\t"
                "add %%rax, %1      \n\t"
                "popcnt %6, %%rax   \n\t"
                "add %%rax, %2      \n\t"
                "popcnt %7, %%rax   \n\t"
                "add %%rax, %3      \n\t"
                : "+r" (c0), "+r" (c1), "+r" (c2), "+r" (c3)
                : "r"  (r0), "r"  (r1), "r"  (r2), "r"  (r3)
                : "rax"
            );
         }
      }
      count = c0 + c1 + c2 + c3;
      endP = chrono::system_clock::now();
      duration=chrono::duration_cast<std::chrono::nanoseconds>(endP-startP).count();
      cout << "Broken Chain\t"  << count << '\t' << (duration/1.0E9) << " sec \t"
            << (10000.0*size)/(duration) << " GB/s" << endl;
   }

   free(charbuffer);
}

An equally interesting benchmark can be found here: http://pastebin.com/kbzgL8si
This benchmark varies the number of popcnts that are in the (false) dependency chain.

False Chain 0:  41959360000 0.57748 sec     18.1578 GB/s
False Chain 1:  41959360000 0.585398 sec    17.9122 GB/s
False Chain 2:  41959360000 0.645483 sec    16.2448 GB/s
False Chain 3:  41959360000 0.929718 sec    11.2784 GB/s
False Chain 4:  41959360000 1.23572 sec     8.48557 GB/s

Function pointer to member function

The syntax is wrong. A member pointer is a different type category from a ordinary pointer. The member pointer will have to be used together with an object of its class:

class A {
public:
 int f();
 int (A::*x)(); // <- declare by saying what class it is a pointer to
};

int A::f() {
 return 1;
}


int main() {
 A a;
 a.x = &A::f; // use the :: syntax
 printf("%d\n",(a.*(a.x))()); // use together with an object of its class
}

a.x does not yet say on what object the function is to be called on. It just says that you want to use the pointer stored in the object a. Prepending a another time as the left operand to the .* operator will tell the compiler on what object to call the function on.

"elseif" syntax in JavaScript

Conditional statements are used to perform different actions based on different conditions.

Use if to specify a block of code to be executed, if a specified condition is true

Use else to specify a block of code to be executed, if the same condition is false

Use else if to specify a new condition to test, if the first condition is false

How to apply a CSS filter to a background image

Now this become even simpler and more flexible by using CSS GRID.You just have to overlap the blured background(imgbg) with the text(h2)

<div class="container">
 <div class="imgbg"></div>
 <h2>
  Lorem ipsum dolor sit amet consectetur, adipisicing elit. Facilis enim
  aut rerum mollitia quas voluptas delectus facere magni cum unde?:)
 </h2>
</div>

and the css:

.container {
        display: grid;
        width: 30em;
      }

.imgbg {
        background: url(bg3.jpg) no-repeat center;
        background-size: cover;
        grid-column: 1/-1;
        grid-row: 1/-1;
        filter: blur(4px);
      }


     .container h2 {
        text-transform: uppercase;
        grid-column: 1/-1;
        grid-row: 1/-1;
        z-index: 2;
      }

getting " (1) no such column: _id10 " error

I think you missed a equal sign at:

Cursor c = ourDatabase.query(DATABASE_TABLE, column, KEY_ROWID + "" + l, null, null, null, null);  

Change to:

Cursor c = ourDatabase.query(DATABASE_TABLE, column, KEY_ROWID + " = " + l, null, null, null, null); 

What's the difference between dependencies, devDependencies and peerDependencies in npm package.json file?

There are some modules and packages only necessary for development, which are not needed in production. Like it says it in the documentation:

If someone is planning on downloading and using your module in their program, then they probably don't want or need to download and build the external test or documentation framework that you use. In this case, it's best to list these additional items in a devDependencies hash.

Include PHP inside JavaScript (.js) files

A slightly modified version based on Blorgbeard one, for easily referenceable associative php arrays to javascript object literals:

PHP File (*.php)

First define an array with the values to be used into javascript files:

<?php
$phpToJsVars = [
  'value1' => 'foo1',
  'value2' => 'foo2'    
];
?>

Now write the php array values into a javascript object literal:

<script type="text/javascript">
var phpVars = { 
<?php 
  foreach ($phpToJsVars as $key => $value) {
    echo '  ' . $key . ': ' . '"' . $value . '",' . "\n";  
  }
?>
};
</script>

Javascript file (*.js)

Now we can access the javscript object literal from any other .js file with the notation:

phpVars["value1"]
phpVars["value2"]

How do you completely remove Ionic and Cordova installation from mac?

Here the command to remove cordova and ionic from your machine

npm uninstall cordova ionic

HTTP Error 403.14 - Forbidden - The Web server is configured to not list the contents of this directory

There can be multiple reasons for the issue. One that worked for me on IIS 8.5 was as follow

Steps

  1. Type "turn windows features on or off" in search.
  2. Click on "Add Roles and features" in Server Manager.
  3. In Wizard scroll down to the Web server and select : Web Server -> Application Development. Select all except CGI from the list as shown in the screen shot

enter image description here

  1. Finally hit next and Install.
  2. Restart IIS

Your website may start working.

How to select clear table contents without destroying the table?

There is a condition that most of these solutions do not address. I revised Patrick Honorez's solution to handle it. I felt I had to share this because I was pulling my hair out when the original function was occasionally clearing more data that I expected.

The situation happens when the table only has one column and the .SpecialCells(xlCellTypeConstants).ClearContents attempts to clear the contents of the top row. In this situation, only one cell is selected (the top row of the table that only has one column) and the SpecialCells command applies to the entire sheet instead of the selected range. What was happening to me was other cells on the sheet that were outside of my table were also getting cleared.

I did some digging and found this advice from Mathieu Guindon: Range SpecialCells ClearContents clears whole sheet

Range({any single cell}).SpecialCells({whatever}) seems to work off the entire sheet.

Range({more than one cell}).SpecialCells({whatever}) seems to work off the specified cells.

If the list/table only has one column (in row 1), this revision will check to see if the cell has a formula and if not, it will only clear the contents of that one cell.

Public Sub ClearList(lst As ListObject)
'Clears a listObject while leaving 1 empty row + formula
' https://stackoverflow.com/a/53856079/1898524
'
'With special help from this post to handle a single column table.
'   Range({any single cell}).SpecialCells({whatever}) seems to work off the entire sheet.
'   Range({more than one cell}).SpecialCells({whatever}) seems to work off the specified cells.
' https://stackoverflow.com/questions/40537537/range-specialcells-clearcontents-clears-whole-sheet-instead

    On Error Resume Next
    
    With lst
        '.Range.Worksheet.Activate ' Enable this if you are debugging 
    
        If .ShowAutoFilter Then .AutoFilter.ShowAllData
        If .DataBodyRange.Rows.Count = 1 Then Exit Sub ' Table is already clear
        .DataBodyRange.Offset(1).Rows.Clear
        
        If .DataBodyRange.Columns.Count > 1 Then ' Check to see if SpecialCells is going to evaluate just one cell.
            .DataBodyRange.Rows(1).SpecialCells(xlCellTypeConstants).ClearContents
        ElseIf Not .Range.HasFormula Then
            ' Only one cell in range and it does not contain a formula.
            .DataBodyRange.Rows(1).ClearContents
        End If

        .Resize .Range.Rows("1:2")
        
        .HeaderRowRange.Offset(1).Select

        ' Reset used range on the sheet
        Dim X
        X = .Range.Worksheet.UsedRange.Rows.Count 'see J-Walkenbach tip 73

    End With

End Sub

A final step I included is a tip that is attributed to John Walkenbach, sometimes noted as J-Walkenbach tip 73 Automatically Resetting The Last Cell

Mapping a JDBC ResultSet to an object

If you don't want to use any JPA provider such as OpenJPA or Hibernate, you can just give Apache DbUtils a try.

http://commons.apache.org/proper/commons-dbutils/examples.html

Then your code will look like this:

QueryRunner run = new QueryRunner(dataSource);

// Use the BeanListHandler implementation to convert all
// ResultSet rows into a List of Person JavaBeans.
ResultSetHandler<List<Person>> h = new BeanListHandler<Person>(Person.class);

// Execute the SQL statement and return the results in a List of
// Person objects generated by the BeanListHandler.
List<Person> persons = run.query("SELECT * FROM Person", h);

Dump all tables in CSV format using 'mysqldump'

First, I can give you the answer for one table:

The trouble with all these INTO OUTFILE or --tab=tmpfile (and -T/path/to/directory) answers is that it requires running mysqldump on the same server as the MySQL server, and having those access rights.

My solution was simply to use mysql (not mysqldump) with the -B parameter, inline the SELECT statement with -e, then massage the ASCII output with sed, and wind up with CSV including a header field row:

Example:

 mysql -B -u username -p password database -h dbhost -e "SELECT * FROM accounts;" \
 | sed "s/\"/\"\"/g;s/'/\'/;s/\t/\",\"/g;s/^/\"/;s/$/\"/;s/\n//g"

"id","login","password","folder","email" "8","mariana","xxxxxxxxxx","mariana","" "3","squaredesign","xxxxxxxxxxxxxxxxx","squaredesign","[email protected]" "4","miedziak","xxxxxxxxxx","miedziak","[email protected]" "5","Sarko","xxxxxxxxx","Sarko","" "6","Logitrans Poland","xxxxxxxxxxxxxx","LogitransPoland","" "7","Amos","xxxxxxxxxxxxxxxxxxxx","Amos","" "9","Annabelle","xxxxxxxxxxxxxxxx","Annabelle","" "11","Brandfathers and Sons","xxxxxxxxxxxxxxxxx","BrandfathersAndSons","" "12","Imagine Group","xxxxxxxxxxxxxxxx","ImagineGroup","" "13","EduSquare.pl","xxxxxxxxxxxxxxxxx","EduSquare.pl","" "101","tmp","xxxxxxxxxxxxxxxxxxxxx","_","[email protected]"

Add a > outfile.csv at the end of that one-liner, to get your CSV file for that table.

Next, get a list of all your tables with

mysql -u username -ppassword dbname -sN -e "SHOW TABLES;"

From there, it's only one more step to make a loop, for example, in the Bash shell to iterate over those tables:

 for tb in $(mysql -u username -ppassword dbname -sN -e "SHOW TABLES;"); do
     echo .....;
 done

Between the do and ; done insert the long command I wrote in Part 1 above, but substitute your tablename with $tb instead.

Uninstall / remove a Homebrew package including all its dependencies

EDIT:

It looks like the issue is now solved using an external command called brew rmdeps or brew rmtree.

To install and use, issue the following commands:

$ brew tap beeftornado/rmtree
$ brew rmtree <package>

See the above link for more information and discussion.


Original answer:

It appears that currently, there's no easy way to accomplish this.

However, I filed an issue on Homebrew's GitHub page, and somebody suggested a temporary solution until they add an exclusive command to solve this.

There's an external command called brew leaves which prints all packages that are not dependencies of other packages.

If you do a logical and on the output of brew leaves and brew deps <package>, you might just get a list of the orphaned dependency packages, which you can uninstall manually afterwards. Combine this with xargs and you'll get what you need, I guess (untested, don't count on this).


EDIT: Somebody just suggested a very similar solution, using join instead of xargs:

brew rm FORMULA
brew rm $(join <(brew leaves) <(brew deps FORMULA))

See the comment on the issue mentioned above for more info.

comparing elements of the same array in java

for (int i = 0; i < a.length; i++) {
    for (int k = 0; k < a.length; k++) {
        if (a[i] != a[k]) {
            System.out.println(a[i] + " not the same with  " + a[k + 1] + "\n");
        }
    }
}

You can start from k=1 & keep "a.length-1" in outer for loop, in order to reduce two comparisions,but that doesnt make any significant difference.

How to avoid the need to specify the WSDL location in a CXF or JAX-WS generated webservice client?

We use

wsdlLocation = "WEB-INF/wsdl/WSDL.wsdl"

In other words, use a path relative to the classpath.

I believe the WSDL may be needed at runtime for validation of messages during marshal/unmarshal.

Solutions for INSERT OR UPDATE on SQL Server

I had tried below solution and it works for me, when concurrent request for insert statement occurs.

begin tran
if exists (select * from table with (updlock,serializable) where key = @key)
begin
   update table set ...
   where key = @key
end
else
begin
   insert table (key, ...)
   values (@key, ...)
end
commit tran

How to call getResources() from a class which has no context?

The normal solution to this is to pass an instance of the context to the class as you create it, or after it is first created but before you need to use the context.

Another solution is to create an Application object with a static method to access the application context although that couples the Droid object fairly tightly into the code.

Edit, examples added

Either modify the Droid class to be something like this

 public Droid(Context context,int x, int y) {
    this.bitmap = BitmapFactory.decodeResource(context.getResources(), R.drawable.birdpic);
    this.x = x;
    this.y = y;
    }   

Or create an Application something like this:

public class App extends android.app.Application
{
    private static App mApp = null;
    /* (non-Javadoc)
     * @see android.app.Application#onCreate()
     */
    @Override
    public void onCreate()
    {
        super.onCreate();
        mApp = this;
    }
    public static Context context()
    {
        return mApp.getApplicationContext();
    }
}

And call App.context() wherever you need a context - note however that not all functions are available on an application context, some are only available on an activity context but it will certainly do with your need for getResources().

Please note that you'll need to add android:name to your application definition in your manifest, something like this:

<application
    android:icon="@drawable/icon"
    android:label="@string/app_name"
    android:name=".App" >

The response content cannot be parsed because the Internet Explorer engine is not available, or

In your invoke web request just use the parameter -UseBasicParsing

e.g. in your script (line 2) you should use:

$rss = Invoke-WebRequest -UseBasicParsing

According to the documentation, this parameter is necessary on systems where IE isn't installed or configured.

Uses the response object for HTML content without Document Object Model (DOM) parsing. This parameter is required when Internet Explorer is not installed on the computers, such as on a Server Core installation of a Windows Server operating system.

How to get disk capacity and free space of remote computer

$disk = Get-WmiObject Win32_LogicalDisk -ComputerName remotecomputer -Filter "DeviceID='C:'" |
Select-Object Size,FreeSpace

$disk.Size
$disk.FreeSpace

To extract the values only and assign them to a variable:

$disk = Get-WmiObject Win32_LogicalDisk -ComputerName remotecomputer -Filter "DeviceID='C:'" |
Foreach-Object {$_.Size,$_.FreeSpace}

How to run .jar file by double click on Windows 7 64-bit?

What is listed in right-click-> Open With ? Is some other program listed as the default program ? Is a Java Runtime listed ? If a Java Runtime is listed, you can open with it, and make it the default program to run with.

ie,

Right Click ->  Properties -> Change -> C:\Program Files\Java\jre7\bin\javaw.exe

How can I scan barcodes on iOS?

For a native iOS 7 bar code scanner take a look at my project on GitHub:

https://github.com/werner77/WECodeScanner

Append column to pandas dataframe

It seems in general you're just looking for a join:

> dat1 = pd.DataFrame({'dat1': [9,5]})
> dat2 = pd.DataFrame({'dat2': [7,6]})
> dat1.join(dat2)
   dat1  dat2
0     9     7
1     5     6

How to randomly pick an element from an array

You can use the Random generator to generate a random index and return the element at that index:

//initialization
Random generator = new Random();
int randomIndex = generator.nextInt(myArray.length);
return myArray[randomIndex];

Difference between SRC and HREF

apnerve's answer was correct before HTML 5 came out, now it's a little more complicated.

For example, the script element, according to the HTML 5 specification, has two global attributes which change how the src attribute functions: async and defer. These change how the script (embedded inline or imported from external file) should be executed.

This means there are three possible modes that can be selected using these attributes:

  1. When the async attribute is present, then the script will be executed asynchronously, as soon as it is available.
  2. When the async attribute is not present but the defer attribute is present, then the script is executed when the page has finished parsing.
  3. When neither attribute is present, then the script is fetched and executed immediately, before the user agent continues parsing the page.

For details please see HTML 5 recommendation

I just wanted to update with a new answer for whoever occasionally visits this topic. Some of the answers should be checked and archived by stackoverflow and every one of us.

Convert ASCII TO UTF-8 Encoding

"ASCII is a subset of UTF-8, so..." - so UTF-8 is a set? :)

In other words: any string build with code points from x00 to x7F has indistinguishable representations (byte sequences) in ASCII and UTF-8. Converting such string is pointless.

Passing a method as a parameter in Ruby

You can use the & operator on the Method instance of your method to convert the method to a block.

Example:

def foo(arg)
  p arg
end

def bar(&block)
  p 'bar'
  block.call('foo')
end

bar(&method(:foo))

More details at http://weblog.raganwald.com/2008/06/what-does-do-when-used-as-unary.html

ASP.NET MVC: What is the purpose of @section?

You want to use sections when you want a bit of code/content to render in a placeholder that has been defined in a layout page.

In the specific example you linked, he has defined the RenderSection in the _Layout.cshtml. Any view that uses that layout can define an @section of the same name as defined in Layout, and it will replace the RenderSection call in the layout.

Perhaps you're wondering how we know Index.cshtml uses that layout? This is due to a bit of MVC/Razor convention. If you look at the dialog where he is adding the view, the box "Use layout or master page" is checked, and just below that it says "Leave empty if it is set in a Razor _viewstart file". It isn't shown, but inside that _ViewStart.cshtml file is code like:

@{
    Layout = "~/Views/Shared/_Layout.cshtml";
}

The way viewstarts work is that any cshtml file within the same directory or child directories will run the ViewStart before it runs itself.

Which is what tells us that Index.cshtml uses Shared/_Layout.cshtml.

How to declare a global variable in C++

You declare the variable as extern in a common header:

//globals.h
extern int x;

And define it in an implementation file.

//globals.cpp
int x = 1337;

You can then include the header everywhere you need access to it.

I suggest you also wrap the variable inside a namespace.

PHP - cannot use a scalar as an array warning

The Other Issue I have seen on this is when nesting arrays this tends to throw the warning, consider the following:

$data = [
"rs" => null
]

this above will work absolutely fine when used like:

$data["rs"] =  5;

But the below will throw a warning ::

$data = [
    "rs" => [
       "rs1" => null;
       ]
    ]
..

$data[rs][rs1] = 2; // this will throw the warning unless assigned to an array

How does EL empty operator work in JSF?

From EL 2.2 specification (get the one below "Click here to download the spec for evaluation"):

1.10 Empty Operator - empty A

The empty operator is a prefix operator that can be used to determine if a value is null or empty.

To evaluate empty A

  • If A is null, return true
  • Otherwise, if A is the empty string, then return true
  • Otherwise, if A is an empty array, then return true
  • Otherwise, if A is an empty Map, return true
  • Otherwise, if A is an empty Collection, return true
  • Otherwise return false

So, considering the interfaces, it works on Collection and Map only. In your case, I think Collection is the best option. Or, if it's a Javabean-like object, then Map. Either way, under the covers, the isEmpty() method is used for the actual check. On interface methods which you can't or don't want to implement, you could throw UnsupportedOperationException.

Submit a form using jQuery

You will have to use $("#formId").submit().

You would generally call this from within a function.

For example:

<input type='button' value='Submit form' onClick='submitDetailsForm()' />

<script language="javascript" type="text/javascript">
    function submitDetailsForm() {
       $("#formId").submit();
    }
</script>

You can get more information on this on the Jquery website.

How to set selected value on select using selectpicker plugin from bootstrap

$('.selectpicker option:selected').val();

Just put option:selected to get value, because the bootstrap selectpicker change to and appear in diferent way. But select still there selected

Laravel Eloquent Join vs Inner Join?

Probably not what you want to hear, but a "feeds" table would be a great middleman for this sort of transaction, giving you a denormalized way of pivoting to all these data with a polymorphic relationship.

You could build it like this:

<?php

Schema::create('feeds', function($table) {
    $table->increments('id');
    $table->timestamps();
    $table->unsignedInteger('user_id');
    $table->foreign('user_id')->references('id')->on('users')->onDelete('cascade');
    $table->morphs('target'); 
});

Build the feed model like so:

<?php

class Feed extends Eloquent
{
    protected $fillable = ['user_id', 'target_type', 'target_id'];

    public function user()
    {
        return $this->belongsTo('User');
    }

    public function target()
    {
        return $this->morphTo();
    }
}

Then keep it up to date with something like:

<?php

Vote::created(function(Vote $vote) {
    $target_type = 'Vote';
    $target_id   = $vote->id;
    $user_id     = $vote->user_id;

    Feed::create(compact('target_type', 'target_id', 'user_id'));
});

You could make the above much more generic/robust—this is just for demonstration purposes.

At this point, your feed items are really easy to retrieve all at once:

<?php

Feed::whereIn('user_id', $my_friend_ids)
    ->with('user', 'target')
    ->orderBy('created_at', 'desc')
    ->get();

How do I resolve "Run-time error '429': ActiveX component can't create object"?

The file msrdo20.dll is missing from the installation.

According to the Support Statement for Visual Basic 6.0 on Windows Vista, Windows Server 2008 and Windows 7 this file should be distributed with the application.

I'm not sure why it isn't, but my solution is to place the file somewhere on the machine, and register it using regsvr32 in the command line, eg:

regsvr32 c:\windows\system32\msrdo20.dll

In an ideal world you would package this up with the redistributable.

Stylesheet not loaded because of MIME-type

I came across this issue having the same problem adding a custom look and feel to an Azure B2C user flow. What I found was that the root that the html page referred to was ../oauth/v2 (i.e. the oauth server path) rather than the path to my storage bob.

Putting in the full url of the pages fixed the problem for me.

Java: How to convert List to Map

Many solutions come to mind, depending on what you want to achive:

Every List item is key and value

for( Object o : list ) {
    map.put(o,o);
}

List elements have something to look them up, maybe a name:

for( MyObject o : list ) {
    map.put(o.name,o);
}

List elements have something to look them up, and there is no guarantee that they are unique: Use Googles MultiMaps

for( MyObject o : list ) {
    multimap.put(o.name,o);
}

Giving all the elements the position as a key:

for( int i=0; i<list.size; i++ ) {
    map.put(i,list.get(i));
}

...

It really depends on what you want to achive.

As you can see from the examples, a Map is a mapping from a key to a value, while a list is just a series of elements having a position each. So they are simply not automatically convertible.

How to read a text file directly from Internet using Java?

For an old school input stream, use this code:

  InputStream in = new URL("http://google.com/").openConnection().getInputStream();

How to check if field is null or empty in MySQL?

Either use

SELECT IF(field1 IS NULL or field1 = '', 'empty', field1) as field1 
from tablename

or

SELECT case when field1 IS NULL or field1 = ''
            then 'empty'
            else field1
       end as field1 
from tablename

If you only want to check for null and not for empty strings then you can also use ifnull() or coalesce(field1, 'empty'). But that is not suitable for empty strings.

Can I have a video with transparent background using HTML5 video tag?

Update: Webm with an alpha channel is now supported in Chrome and Firefox.

For other browers, there are workarounds, but they involve re-rendering the video using Canvas and it is kind of a hack. seeThru is one example. It works pretty well on HTML5 desktop browsers (even IE9) but it doesn't seem to work very well on mobile. I couldn't get it to work at all on Chrome for Android. It did work on Firefox for Android but with a pretty lousy framerate. I think you might be out of luck for mobile, although I'd love to be proven wrong.

How can we redirect a Java program console output to multiple files?

Go to run as and choose Run Configurations -> Common and in the Standard Input and Output you can choose a File also.

Using jquery to delete all elements with a given id

id of dom element shout be unique. Use class instead (<span class='myclass'>). To remove all span with this class:

$('.myclass').remove()

Find commit by hash SHA in Git

Just use the following command

git show a2c25061

or (the exact equivalent):

git log -p -1 a2c25061

Why would one mark local variables and method parameters as "final" in Java?

In the case of local variables, I tend to avoid this. It causes visual clutter, and is generally unnecessary - a function should be short enough or focus on a single impact to let you quickly see that you are modify something that shouldn't be.

In the case of magic numbers, I would put them as a constant private field anyway rather than in the code.

I only use final in situations where it is necessary (e.g., passing values to anonymous classes).

Android fastboot waiting for devices

To use the fastboot command you first need to put your device in fastboot mode:

$ adb reboot bootloader

Once the device is in fastboot mode, you can boot it with your own kernel, for example:

$ fastboot boot myboot.img

The above will only boot your kernel once and the old kernel will be used again when you reboot the device. To replace the kernel on the device, you will need to flash it to the device:

$ fastboot flash boot myboot.img

Hope that helps.

Read an Excel file directly from a R script

As noted above in many of the other answers, there are many good packages that connect to the XLS/X file and get the data in a reasonable way. However, you should be warned that under no circumstances should you use the clipboard (or a .csv) file to retrieve data from Excel. To see why, enter =1/3 into a cell in excel. Now, reduce the number of decimal points visible to you to two. Then copy and paste the data into R. Now save the CSV. You'll notice in both cases Excel has helpfully only kept the data that was visible to you through the interface and you've lost all of the precision in your actual source data.

VBA procedure to import csv file into access

The easiest way to do it is to link the CSV-file into the Access database as a table. Then you can work on this table as if it was an ordinary access table, for instance by creating an appropriate query based on this table that returns exactly what you want.

You can link the table either manually or with VBA like this

DoCmd.TransferText TransferType:=acLinkDelim, TableName:="tblImport", _
    FileName:="C:\MyData.csv", HasFieldNames:=true

UPDATE

Dim db As DAO.Database

' Re-link the CSV Table
Set db = CurrentDb
On Error Resume Next:   db.TableDefs.Delete "tblImport":   On Error GoTo 0
db.TableDefs.Refresh
DoCmd.TransferText TransferType:=acLinkDelim, TableName:="tblImport", _
    FileName:="C:\MyData.csv", HasFieldNames:=true
db.TableDefs.Refresh

' Perform the import
db.Execute "INSERT INTO someTable SELECT col1, col2, ... FROM tblImport " _
   & "WHERE NOT F1 IN ('A1', 'A2', 'A3')"
db.Close:   Set db = Nothing

How open PowerShell as administrator from the run window

The easiest way to open an admin Powershell window in Windows 10 (and Windows 8) is to add a "Windows Powershell (Admin)" option to the "Power User Menu". Once this is done, you can open an admin powershell window via Win+X,A or by right-clicking on the start button and selecting "Windows Powershell (Admin)":

[Windows 10/Windows 8 Power User menu with "Windows Powershell (Admin)

Here's where you replace the "Command Prompt" option with a "Windows Powershell" option:

[Taskbar and Start Menu Properties: "Replace Command Prompt With Windows Powershell"

Can't access object property, even though it shows up in a console log

If this is an issue occurring when working with Mongoose, the following may happen:

console.log(object)

returns everything, including the desired key.

console.log(object.key)

returns undefined.

If that is happening, it means that the key is missing from the Mongoose Schema. Adding it in will resolve the issue.

How can I include a YAML file inside another?

Probably it was not supported when question was asked but you can import other YAML file into one:

imports: [/your_location_to_yaml_file/Util.area.yaml]

Though I don't have any online reference but this works for me.

How to enable native resolution for apps on iPhone 6 and 6 Plus?

I didn't want to introduce an asset catalog.

Per the answer from seahorseseaeo here, adding the following to info.plist worked for me. (I edited it as a "source code".) I then named the images [email protected] and [email protected]

<key>UILaunchImages</key>
<array>
    <dict>
        <key>UILaunchImageMinimumOSVersion</key>
        <string>8.0</string>
        <key>UILaunchImageName</key>
        <string>Default-667h</string>
        <key>UILaunchImageOrientation</key>
        <string>Portrait</string>
        <key>UILaunchImageSize</key>
        <string>{375, 667}</string>
    </dict>
    <dict>
        <key>UILaunchImageMinimumOSVersion</key>
        <string>8.0</string>
        <key>UILaunchImageName</key>
        <string>Default-736h</string>
        <key>UILaunchImageOrientation</key>
        <string>Portrait</string>
        <key>UILaunchImageSize</key>
        <string>{414, 736}</string>
    </dict>
</array>

How to convert map to url query string?

This is the solution I implemented, using Java 8 and org.apache.http.client.URLEncodedUtils. It maps the entries of the map into a list of BasicNameValuePair and then uses Apache's URLEncodedUtils to turn that into a query string.

List<BasicNameValuePair> nameValuePairs = params.entrySet().stream()
   .map(entry -> new BasicNameValuePair(entry.getKey(), entry.getValue()))
   .collect(Collectors.toList());

URLEncodedUtils.format(nameValuePairs, Charset.forName("UTF-8"));

Best way to store password in database

I may be slightly off-topic as you did mention the need for a username and password, and my understanding of the issue is admitedly not the best but is OpenID something worth considering?

If you use OpenID then you don't end up storing any credentials at all if I understand the technology correctly and users can use credentials that they already have, avoiding the need to create a new identity that is specific to your application.

It may not be suitable if the application in question is purely for internal use though

RPX provides a nice easy way to intergrate OpenID support into an application.

UITableView example for Swift

For completeness sake, and for those that do not wish to use the Interface Builder, here's a way of creating the same table as in Suragch's answer entirely programatically - albeit with a different size and position.

class ViewController: UIViewController, UITableViewDelegate, UITableViewDataSource  {

    var tableView: UITableView = UITableView()
    let animals = ["Horse", "Cow", "Camel", "Sheep", "Goat"]
    let cellReuseIdentifier = "cell"

    override func viewDidLoad() {
        super.viewDidLoad()

        tableView.frame = CGRectMake(0, 50, 320, 200)
        tableView.delegate = self
        tableView.dataSource = self
        tableView.registerClass(UITableViewCell.self, forCellReuseIdentifier: cellReuseIdentifier)

        self.view.addSubview(tableView)
    }

    func tableView(tableView: UITableView, numberOfRowsInSection section: Int) -> Int {
        return animals.count
    }

    func tableView(tableView: UITableView, cellForRowAtIndexPath indexPath: NSIndexPath) -> UITableViewCell {
        let cell:UITableViewCell = tableView.dequeueReusableCellWithIdentifier(cellReuseIdentifier) as UITableViewCell!

        cell.textLabel?.text = animals[indexPath.row]

        return cell
    }

    func tableView(tableView: UITableView, didSelectRowAtIndexPath indexPath: NSIndexPath) {
        print("You tapped cell number \(indexPath.row).")
    }

}

Make sure you have remembered to import UIKit.

lambda expression for exists within list

If listOfIds is a list, this will work, but, List.Contains() is a linear search, so this isn't terribly efficient.

You're better off storing the ids you want to look up into a container that is suited for searching, like Set.

List<int> listOfIds = new List(GetListOfIds());
lists.Where(r=>listOfIds.Contains(r.Id));

What is the --save option for npm install?

according to NPM Doc

enter image description here

So it seems that by running npm install package_name, the package dependency should be automatically added to package.json right?

Is it possible to install another version of Python to Virtualenv?

Pre-requisites:

  1. sudo easy_install virtualenv
  2. sudo pip install virtualenvwrapper

Installing virtualenv with Python2.6:

  1. You could manually download, build and install another version of Python to /usr/local or another location.

  2. If it's another location other than /usr/local, add it to your PATH.

  3. Reload your shell to pick up the updated PATH.

  4. From this point on, you should be able to call the following 2 python binaries from your shell python2.5 and python2.6

  5. Create a new instance of virtualenv with python2.6:

    mkvirtualenv --python=python2.6 yournewenv

increase font size of hyperlink text html

increase the padding size of font and then try to increase font size:-

style="padding-bottom:40px; font-size: 50px;"

java.io.FileNotFoundException: /storage/emulated/0/New file.txt: open failed: EACCES (Permission denied)

Implement runtime permission for running your app on Android 6.0 Marshmallow (API 23) or later.

or you can manually enable the storage permission-

goto settings>apps> "your_app_name" >click on it >then click permissions> then enable the storage. Thats it.

But i suggest go the for first one which is, Implement runtime permissions in your code.

Duplicate / Copy records in the same MySQL table

A late answer I know, but it still a common question, I would like to add another answer that It worked for me, with only using a single line insert into statement, and I think it is straightforward, without creating any new table (since it could be an issue with CREATE TEMPORARY TABLE permissions):

INSERT INTO invoices (col_1, col_2, col_3, ... etc)
  SELECT
    t.col_1,
    t.col_2,
    t.col_3,
    ...
    t.updated_date,
  FROM invoices t;

The solution is working for AUTO_INCREMENT id column, otherwise, you can add ID column as well to statement:

INSERT INTO invoices (ID, col_1, col_2, col_3, ... etc)
  SELECT
    MAX(ID)+1,
    t.col_1,
    t.col_2,
    t.col_3,
    ... etc ,
  FROM invoices t;

It is really easy and straightforward, you can update anything else in a single line without any second update statement for later, (ex: update a title column with extra text or replacing a string with another), also you can be specific with what exactly you want to duplicate, if all then it is, if some, you can do so.

Exporting data In SQL Server as INSERT INTO

for SQl server Mng Studio 2016:

enter image description here

PostgreSQL Autoincrement

Starting with Postgres 10, identity columns as defined by the SQL standard are also supported:

create table foo 
(
  id integer generated always as identity
);

creates an identity column that can't be overridden unless explicitly asked for. The following insert will fail with a column defined as generated always:

insert into foo (id) 
values (1);

This can however be overruled:

insert into foo (id) overriding system value 
values (1);

When using the option generated by default this is essentially the same behaviour as the existing serial implementation:

create table foo 
(
  id integer generated by default as identity
);

When a value is supplied manually, the underlying sequence needs to be adjusted manually as well - the same as with a serial column.


An identity column is not a primary key by default (just like a serial column). If it should be one, a primary key constraint needs to be defined manually.

Detect Safari using jQuery

Using a mix of feature detection and Useragent string:

    var is_opera = !!window.opera || navigator.userAgent.indexOf(' OPR/') >= 0;
    var is_Edge = navigator.userAgent.indexOf("Edge") > -1;
    var is_chrome = !!window.chrome && !is_opera && !is_Edge;
    var is_explorer= typeof document !== 'undefined' && !!document.documentMode && !is_Edge;
    var is_firefox = typeof window.InstallTrigger !== 'undefined';
    var is_safari = /^((?!chrome|android).)*safari/i.test(navigator.userAgent);

Usage:
if (is_safari) alert('Safari');

Or for Safari only, use this :

if ( /^((?!chrome|android).)*safari/i.test(navigator.userAgent)) {alert('Its Safari');}

Angular 4 setting selected option in Dropdown

If you want to select a value as default, in your form builder give it a value :

this.myForm = this.FB.group({
    mySelect: [this.options[0].key, [/* Validators here */]]
});

Now in your HTML :

<form [formGroup]="myForm">
    <select [formControlName]="mySelect">
        <option *ngFor="let opt of options" [value]="opt.key">ANY TEXT YOU WANT HERE</option>
    </select>
</form>

What my code does is giving your select a value, that is equal to the first value of your options list. This is how you select an option as default in Angular, selected is useless.

Calling a function every 60 seconds

A better use of jAndy's answer to implement a polling function that polls every interval seconds, and ends after timeout seconds.

function pollFunc(fn, timeout, interval) {
    var startTime = (new Date()).getTime();
    interval = interval || 1000;

    (function p() {
        fn();
        if (((new Date).getTime() - startTime ) <= timeout)  {
            setTimeout(p, interval);
        }
    })();
}

pollFunc(sendHeartBeat, 60000, 1000);

UPDATE

As per the comment, updating it for the ability of the passed function to stop the polling:

function pollFunc(fn, timeout, interval) {
    var startTime = (new Date()).getTime();
    interval = interval || 1000,
    canPoll = true;

    (function p() {
        canPoll = ((new Date).getTime() - startTime ) <= timeout;
        if (!fn() && canPoll)  { // ensures the function exucutes
            setTimeout(p, interval);
        }
    })();
}

pollFunc(sendHeartBeat, 60000, 1000);

function sendHeartBeat(params) {
    ...
    ...
    if (receivedData) {
        // no need to execute further
        return true; // or false, change the IIFE inside condition accordingly.
    }
}

New Line Issue when copying data from SQL Server 2012 to Excel

Line Split Issues when Copying Data from SQL Server to Excel. see below example and try using replace some characters.

SELECT replace(replace(CountyCode, char(10), ''), char(13), '') 
FROM [MSSQLTipsDemo].[dbo].[CountryInfo]

"Input string was not in a correct format."

If you are not validating explicitly for numbers in the text field, in any case its better to use

int result=0;
if(int.TryParse(textBox1.Text,out result))

Now if the result is success then you can proceed with your calculations.

How do I concatenate or merge arrays in Swift?

With Swift 5, according to your needs, you may choose one of the six following ways to concatenate/merge two arrays.


#1. Merge two arrays into a new array with Array's +(_:_:) generic operator

Array has a +(_:_:) generic operator. +(_:_:) has the following declaration:

Creates a new collection by concatenating the elements of a collection and a sequence.

static func + <Other>(lhs: Array<Element>, rhs: Other) -> Array<Element> where Other : Sequence, Self.Element == Other.Element

The following Playground sample code shows how to merge two arrays of type [Int] into a new array using +(_:_:) generic operator:

let array1 = [1, 2, 3]
let array2 = [4, 5, 6]

let flattenArray = array1 + array2
print(flattenArray) // prints [1, 2, 3, 4, 5, 6]

#2. Append the elements of an array into an existing array with Array's +=(_:_:) generic operator

Array has a +=(_:_:) generic operator. +=(_:_:) has the following declaration:

Appends the elements of a sequence to a range-replaceable collection.

static func += <Other>(lhs: inout Array<Element>, rhs: Other) where Other : Sequence, Self.Element == Other.Element

The following Playground sample code shows how to append the elements of an array of type [Int] into an existing array using +=(_:_:) generic operator:

var array1 = [1, 2, 3]
let array2 = [4, 5, 6]

array1 += array2
print(array1) // prints [1, 2, 3, 4, 5, 6]

#3. Append an array to another array with Array's append(contentsOf:) method

Swift Array has an append(contentsOf:) method. append(contentsOf:) has the following declaration:

Adds the elements of a sequence or collection to the end of this collection.

mutating func append<S>(contentsOf newElements: S) where S : Sequence, Self.Element == S.Element

The following Playground sample code shows how to append an array to another array of type [Int] using append(contentsOf:) method:

var array1 = [1, 2, 3]
let array2 = [4, 5, 6]

array1.append(contentsOf: array2)
print(array1) // prints [1, 2, 3, 4, 5, 6]

#4. Merge two arrays into a new array with Sequence's flatMap(_:) method

Swift provides a flatMap(_:) method for all types that conform to Sequence protocol (including Array). flatMap(_:) has the following declaration:

Returns an array containing the concatenated results of calling the given transformation with each element of this sequence.

func flatMap<SegmentOfResult>(_ transform: (Self.Element) throws -> SegmentOfResult) rethrows -> [SegmentOfResult.Element] where SegmentOfResult : Sequence

The following Playground sample code shows how to merge two arrays of type [Int] into a new array using flatMap(_:) method:

let array1 = [1, 2, 3]
let array2 = [4, 5, 6]

let flattenArray = [array1, array2].flatMap({ (element: [Int]) -> [Int] in
    return element
})
print(flattenArray) // prints [1, 2, 3, 4, 5, 6]

#5. Merge two arrays into a new array with Sequence's joined() method and Array's init(_:) initializer

Swift provides a joined() method for all types that conform to Sequence protocol (including Array). joined() has the following declaration:

Returns the elements of this sequence of sequences, concatenated.

func joined() -> FlattenSequence<Self>

Besides, Swift Array has a init(_:) initializer. init(_:) has the following declaration:

Creates an array containing the elements of a sequence.

init<S>(_ s: S) where Element == S.Element, S : Sequence

Therefore, the following Playground sample code shows how to merge two arrays of type [Int] into a new array using joined() method and init(_:) initializer:

let array1 = [1, 2, 3]
let array2 = [4, 5, 6]

let flattenCollection = [array1, array2].joined() // type: FlattenBidirectionalCollection<[Array<Int>]>
let flattenArray = Array(flattenCollection)
print(flattenArray) // prints [1, 2, 3, 4, 5, 6]

#6. Merge two arrays into a new array with Array's reduce(_:_:) method

Swift Array has a reduce(_:_:) method. reduce(_:_:) has the following declaration:

Returns the result of combining the elements of the sequence using the given closure.

func reduce<Result>(_ initialResult: Result, _ nextPartialResult: (Result, Element) throws -> Result) rethrows -> Result

The following Playground code shows how to merge two arrays of type [Int] into a new array using reduce(_:_:) method:

let array1 = [1, 2, 3]
let array2 = [4, 5, 6]

let flattenArray = [array1, array2].reduce([], { (result: [Int], element: [Int]) -> [Int] in
    return result + element
})
print(flattenArray) // prints [1, 2, 3, 4, 5, 6]

Android sqlite how to check if a record exists

One thing the top voted answer did not mention was that you need single quotes, 'like this', around your search value if it is a text value like so:

public boolean checkIfMyTitleExists(String title) {
    String Query = "Select * from " + TABLE_NAME + " where " + COL1 + " = " + "'" + title + "'";
    Cursor cursor = database.rawQuery(Query, null);
    if(cursor.getCount() <= 0){
        cursor.close();
        return false;
    }
    cursor.close();

    return true;
}

Otherwise, you will get a "SQL(query) error or missing database" error like I did without the single quotes around the title field.

If it is a numeric value, it does not need single quotes.

Refer to this SQL post for more details

Error:Execution failed for task ':app:compileDebugKotlin'. > Compilation error. See log for more details

I had misleading error messages similar to the ones posted in the question:

Compilation error. See log for more details

And:

org.gradle.api.tasks.TaskExecutionException: Execution failed for task ':app:compileDebugKotlin'.
    at org.gradle.api.internal.tasks.execution.ExecuteActionsTaskExecuter.executeActions(ExecuteActionsTaskExecuter.java:100)
    at org.gradle.api.internal.tasks.execution.ExecuteActionsTaskExecuter.execute(ExecuteActionsTaskExecuter.java:70)
    at org.gradle.api.internal.tasks.execution.OutputDirectoryCreatingTaskExecuter.execute(OutputDirectoryCreatingTaskExecuter.java:51)
    at org.gradle.api.internal.tasks.execution.SkipUpToDateTaskExecuter.execute(SkipUpToDateTaskExecuter.java:62)
    at org.gradle.api.internal.tasks.execution.ResolveTaskOutputCachingStateExecuter.execute(ResolveTaskOutputCachingStateExecuter.java:54)
    at org.gradle.api.internal.tasks.execution.ValidatingTaskExecuter.execute(ValidatingTaskExecuter.java:60)
    at org.gradle.api.internal.tasks.execution.SkipEmptySourceFilesTaskExecuter.execute(SkipEmptySourceFilesTaskExecuter.java:97)
    at org.gradle.api.internal.tasks.execution.CleanupStaleOutputsExecuter.execute(CleanupStaleOutputsExecuter.java:87)
    at org.gradle.api.internal.tasks.execution.ResolveTaskArtifactStateTaskExecuter.execute(ResolveTaskArtifactStateTaskExecuter.java:52)
    at org.gradle.api.internal.tasks.execution.SkipTaskWithNoActionsExecuter.execute(SkipTaskWithNoActionsExecuter.java:52)
    at org.gradle.api.internal.tasks.execution.SkipOnlyIfTaskExecuter.execute(SkipOnlyIfTaskExecuter.java:54)
    at org.gradle.api.internal.tasks.execution.ExecuteAtMostOnceTaskExecuter.execute(ExecuteAtMostOnceTaskExecuter.java:43)
    at org.gradle.api.internal.tasks.execution.CatchExceptionTaskExecuter.execute(CatchExceptionTaskExecuter.java:34)
    at org.gradle.execution.taskgraph.DefaultTaskGraphExecuter$EventFiringTaskWorker$1.run(DefaultTaskGraphExecuter.java:248)
    at org.gradle.internal.progress.DefaultBuildOperationExecutor$RunnableBuildOperationWorker.execute(DefaultBuildOperationExecutor.java:336)
    at org.gradle.internal.progress.DefaultBuildOperationExecutor$RunnableBuildOperationWorker.execute(DefaultBuildOperationExecutor.java:328)
    at org.gradle.internal.progress.DefaultBuildOperationExecutor.execute(DefaultBuildOperationExecutor.java:199)
    at org.gradle.internal.progress.DefaultBuildOperationExecutor.run(DefaultBuildOperationExecutor.java:110)
    at org.gradle.execution.taskgraph.DefaultTaskGraphExecuter$EventFiringTaskWorker.execute(DefaultTaskGraphExecuter.java:241)
    at org.gradle.execution.taskgraph.DefaultTaskGraphExecuter$EventFiringTaskWorker.execute(DefaultTaskGraphExecuter.java:230)
    at org.gradle.execution.taskgraph.DefaultTaskPlanExecutor$TaskExecutorWorker.processTask(DefaultTaskPlanExecutor.java:123)
    at org.gradle.execution.taskgraph.DefaultTaskPlanExecutor$TaskExecutorWorker.access$200(DefaultTaskPlanExecutor.java:79)
    at org.gradle.execution.taskgraph.DefaultTaskPlanExecutor$TaskExecutorWorker$1.execute(DefaultTaskPlanExecutor.java:104)
    at org.gradle.execution.taskgraph.DefaultTaskPlanExecutor$TaskExecutorWorker$1.execute(DefaultTaskPlanExecutor.java:98)
    at org.gradle.execution.taskgraph.DefaultTaskExecutionPlan.execute(DefaultTaskExecutionPlan.java:626)
    at org.gradle.execution.taskgraph.DefaultTaskExecutionPlan.executeWithTask(DefaultTaskExecutionPlan.java:581)
    at org.gradle.execution.taskgraph.DefaultTaskPlanExecutor$TaskExecutorWorker.run(DefaultTaskPlanExecutor.java:98)
    at org.gradle.internal.concurrent.ExecutorPolicy$CatchAndRecordFailures.onExecute(ExecutorPolicy.java:63)
    at org.gradle.internal.concurrent.ManagedExecutorImpl$1.run(ManagedExecutorImpl.java:46)
    at java.util.concurrent.ThreadPoolExecutor.runWorker(ThreadPoolExecutor.java:1142)
    at java.util.concurrent.ThreadPoolExecutor$Worker.run(ThreadPoolExecutor.java:617)
    at org.gradle.internal.concurrent.ThreadFactoryImpl$ManagedThreadRunnable.run(ThreadFactoryImpl.java:55)
    at java.lang.Thread.run(Thread.java:745)
Caused by: org.gradle.api.GradleException: Compilation error. See log for more details
    at org.jetbrains.kotlin.gradle.tasks.TasksUtilsKt.throwGradleExceptionIfError(tasksUtils.kt:16)
    at org.jetbrains.kotlin.gradle.tasks.KotlinCompile.processCompilerExitCode(Tasks.kt:429)
    at org.jetbrains.kotlin.gradle.tasks.KotlinCompile.callCompiler$kotlin_gradle_plugin(Tasks.kt:390)
    at org.jetbrains.kotlin.gradle.tasks.KotlinCompile.callCompiler$kotlin_gradle_plugin(Tasks.kt:274)
    at org.jetbrains.kotlin.gradle.tasks.AbstractKotlinCompile.execute(Tasks.kt:233)
    at sun.reflect.NativeMethodAccessorImpl.invoke0(Native Method)
    at sun.reflect.NativeMethodAccessorImpl.invoke(NativeMethodAccessorImpl.java:62)
    at sun.reflect.DelegatingMethodAccessorImpl.invoke(DelegatingMethodAccessorImpl.java:43)
    at java.lang.reflect.Method.invoke(Method.java:498)
    at org.gradle.internal.reflect.JavaMethod.invoke(JavaMethod.java:73)
    at org.gradle.api.internal.project.taskfactory.IncrementalTaskAction.doExecute(IncrementalTaskAction.java:46)
    at org.gradle.api.internal.project.taskfactory.StandardTaskAction.execute(StandardTaskAction.java:39)
    at org.gradle.api.internal.project.taskfactory.StandardTaskAction.execute(StandardTaskAction.java:26)
    at org.gradle.api.internal.tasks.execution.ExecuteActionsTaskExecuter$1.run(ExecuteActionsTaskExecuter.java:121)
    at org.gradle.internal.progress.DefaultBuildOperationExecutor$RunnableBuildOperationWorker.execute(DefaultBuildOperationExecutor.java:336)
    at org.gradle.internal.progress.DefaultBuildOperationExecutor$RunnableBuildOperationWorker.execute(DefaultBuildOperationExecutor.java:328)
    at org.gradle.internal.progress.DefaultBuildOperationExecutor.execute(DefaultBuildOperationExecutor.java:199)
    at org.gradle.internal.progress.DefaultBuildOperationExecutor.run(DefaultBuildOperationExecutor.java:110)
    at org.gradle.api.internal.tasks.execution.ExecuteActionsTaskExecuter.executeAction(ExecuteActionsTaskExecuter.java:110)
    at org.gradle.api.internal.tasks.execution.ExecuteActionsTaskExecuter.executeActions(ExecuteActionsTaskExecuter.java:92)
    ... 32 more

Solution:

I solved it by

  1. Clicking on Gradle (on the right side bar) ->
  2. Then under :app
  3. Then choose assembleDebug (or assembleYourFlavor if you use flavors)

In Picture:

1 & 2:

s1

3:

s2

Error will show up in Run: tab.

Try/catch does not seem to have an effect

I was able to duplicate your result when trying to run a remote WMI query. The exception thrown is not caught by the Try/Catch, nor will a Trap catch it, since it is not a "terminating error". In PowerShell, there are terminating errors and non-terminating errors . It appears that Try/Catch/Finally and Trap only works with terminating errors.

It is logged to the $error automatic variable and you can test for these type of non-terminating errors by looking at the $? automatic variable, which will let you know if the last operation succeeded ($true) or failed ($false).

From the appearance of the error generated, it appears that the error is returned and not wrapped in a catchable exception. Below is a trace of the error generated.

PS C:\scripts\PowerShell> Trace-Command -Name errorrecord  -Expression {Get-WmiObject win32_bios -ComputerName HostThatIsNotThere}  -PSHost
DEBUG: InternalCommand Information: 0 :  Constructor Enter Ctor
Microsoft.PowerShell.Commands.GetWmiObjectCommand: 25857563
DEBUG: InternalCommand Information: 0 :  Constructor Leave Ctor
Microsoft.PowerShell.Commands.GetWmiObjectCommand: 25857563
DEBUG: ErrorRecord Information: 0 :  Constructor Enter Ctor
System.Management.Automation.ErrorRecord: 19621801 exception =
System.Runtime.InteropServices.COMException (0x800706BA): The RPC
server is unavailable. (Exception from HRESULT: 0x800706BA)
   at
System.Runtime.InteropServices.Marshal.ThrowExceptionForHRInternal(Int32 errorCode, IntPtr errorInfo)
   at System.Management.ManagementScope.InitializeGuts(Object o)
   at System.Management.ManagementScope.Initialize()
   at System.Management.ManagementObjectSearcher.Initialize()
   at System.Management.ManagementObjectSearcher.Get()
   at Microsoft.PowerShell.Commands.GetWmiObjectCommand.BeginProcessing()
errorId = GetWMICOMException errorCategory = InvalidOperation
targetObject =
DEBUG: ErrorRecord Information: 0 :  Constructor Leave Ctor
System.Management.Automation.ErrorRecord: 19621801

A work around for your code could be:

try
{
    $colItems = get-wmiobject -class "Win32_PhysicalMemory" -namespace "root\CIMV2" -computername $strComputerName -Credential $credentials
    if ($?)
    {
      foreach ($objItem in $colItems) 
      {
          write-host "Bank Label: " $objItem.BankLabel
          write-host "Capacity: " ($objItem.Capacity / 1024 / 1024)
          write-host "Caption: " $objItem.Caption
          write-host "Creation Class Name: " $objItem.CreationClassName      
          write-host
      }
    }
    else
    {
       throw $error[0].Exception
    }

Prevent direct access to a php include file

Add this to the page that you want to only be included

<?php
if(!defined('MyConst')) {
   die('Direct access not permitted');
}
?>

then on the pages that include it add

<?php
define('MyConst', TRUE);
?>

Serialize an object to XML

I have a simple way to serialize an object to XML using C#, it works great and it's highly reusable. I know this is an older thread, but I wanted to post this because someone may find this helpful to them.

Here is how I call the method:

var objectToSerialize = new MyObject();
var xmlString = objectToSerialize.ToXmlString();

Here is the class that does the work:

Note: Since these are extension methods they need to be in a static class.

using System.IO;
using System.Xml.Serialization;

public static class XmlTools
{
    public static string ToXmlString<T>(this T input)
    {
        using (var writer = new StringWriter())
        {
            input.ToXml(writer);
            return writer.ToString();
        }
    }

    private static void ToXml<T>(this T objectToSerialize, StringWriter writer)
    {
        new XmlSerializer(typeof(T)).Serialize(writer, objectToSerialize);
    }
}

Configuring so that pip install can work from github

I had similar issue when I had to install from github repo, but did not want to install git , etc.

The simple way to do it is using zip archive of the package. Add /zipball/master to the repo URL:

    $ pip install https://github.com/hmarr/django-debug-toolbar-mongo/zipball/master
Downloading/unpacking https://github.com/hmarr/django-debug-toolbar-mongo/zipball/master
  Downloading master
  Running setup.py egg_info for package from https://github.com/hmarr/django-debug-toolbar-mongo/zipball/master
Installing collected packages: django-debug-toolbar-mongo
  Running setup.py install for django-debug-toolbar-mongo
Successfully installed django-debug-toolbar-mongo
Cleaning up...

This way you will make pip work with github source repositories.

path.join vs path.resolve with __dirname

Yes there is a difference between the functions but the way you are using them in this case will result in the same outcome.

path.join returns a normalized path by merging two paths together. It can return an absolute path, but it doesn't necessarily always do so.

For instance:

path.join('app/libs/oauth', '/../ssl')

resolves to app/libs/ssl

path.resolve, on the other hand, will resolve to an absolute path.

For instance, when you run:

path.resolve('bar', '/foo');

The path returned will be /foo since that is the first absolute path that can be constructed.

However, if you run:

path.resolve('/bar/bae', '/foo', 'test');

The path returned will be /foo/test again because that is the first absolute path that can be formed from right to left.

If you don't provide a path that specifies the root directory then the paths given to the resolve function are appended to the current working directory. So if your working directory was /home/mark/project/:

path.resolve('test', 'directory', '../back');

resolves to

/home/mark/project/test/back

Using __dirname is the absolute path to the directory containing the source file. When you use path.resolve or path.join they will return the same result if you give the same path following __dirname. In such cases it's really just a matter of preference.

python: after installing anaconda, how to import pandas

I know there are a lot of answers to this already but I would like to put in my two cents. When creating a virtual environment in anaconda launcher you still need to install the packages you need. This is deceiving because I assumed since I was using anaconda that packages such as pandas, numpy etc would be include. This is not the case. It gives you a fresh environment with none of those packages installed, at least mine did. All my packages installed into the environment with no problem and work correctly.

Row names & column names in R

I think that using colnames and rownames makes the most sense; here's why.

Using names has several disadvantages. You have to remember that it means "column names", and it only works with data frame, so you'll need to call colnames whenever you use matrices. By calling colnames, you only have to remember one function. Finally, if you look at the code for colnames, you will see that it calls names in the case of a data frame anyway, so the output is identical.

rownames and row.names return the same values for data frame and matrices; the only difference that I have spotted is that where there aren't any names, rownames will print "NULL" (as does colnames), but row.names returns it invisibly. Since there isn't much to choose between the two functions, rownames wins on the grounds of aesthetics, since it pairs more prettily withcolnames. (Also, for the lazy programmer, you save a character of typing.)

ENOENT, no such file or directory

Another possibility is that you are missing an .npmrc file if you are pulling any packages that are not publicly available.

You will need to add an .npmrc file at the root directory and add the private/internal registry inside of the .npmrc file like this:

registry=http://private.package.source/secret/npm-packages/

Conversion of a varchar data type to a datetime data type resulted in an out-of-range value in SQL query

hope this may help you:

SELECT  CAST(LoginTime AS DATE)
         FROM    AuditTrail 

If you want to have some filters over this datetime or it's different parts, you can use built-in functions such as Year and Month

Bootstrap navbar Active State not working

when use header.php for every page for the navbar code, the jquery does not work, the active is applied and then removed, a simple solution, is as follows

on every page set variable <?php $pageName = "index"; ?> on Index page and similarly <?php $pageName = "contact"; ?> on Contact us page

then call the header.php (ie the nav code is in header.php) <?php include('header.php'); >

in the header.php ensure that each nav-link is as follows

<a class="nav-link <?php if ($page_name == 'index') {echo "active";} ?> href="index.php">Home</a>

<a class="nav-link <?php if ($page_name == 'contact') {echo "active";} ?> href="contact.php">Contact Us</a>

hope this helps cause i have spent days to get the jquery to work but failed,

if someone would kindly explain what exactly is the issue when the header.php is included and then page loads... why the jquery fails to add the active class to the nav-link..??

IntelliJ IDEA generating serialVersionUID

After spending some time on Serialization, I find that, we should not generate serialVersionUID with some random value, we should give it a meaningful value.

Here is a details comment on this. I am coping the comment here.

Actually, you should not be "generating" serial version UIDs. It is a dumb "feature" that stems from the general misunderstanding of how that ID is used by Java. You should be giving these IDs meaningful, readable values, e.g. starting with 1L, and incrementing them each time you think the new version of the class should render all previous versions (that might be previously serialized) obsolete. All utilities that generate such IDs basically do what the JVM does when the ID is not defined: they generate the value based on the content of the class file, hence coming up with unreadable meaningless long integers. If you want each and every version of your class to be distinct (in the eyes of the JVM) then you should not even specify the serialVersionUID value isnce the JVM will produce one on the fly, and the value of each version of your class will be unique. The purpose of defining that value explicitly is to tell the serialization mechanism to treat different versions of the class that have the same SVUID as if they are the same, e.g. not to reject the older serialized versions. So, if you define the ID and never change it (and I assume that's what you do since you rely on the auto-generation, and you probably never re-generate your IDs) you are ensuring that all - even absolutely different - versions of your class will be considered the same by the serialization mechanism. Is that what you want? If not, and if you indeed want to have control over how your objects are recognized, you should be using simple values that you yourself can understand and easily update when you decide that the class has changed significantly. Having a 23-digit value does not help at all.

Hope this helps. Good luck.

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

To get this working for Calabash automated tests

There is a pull request up to fix the issue of xcode 12 not working with calabash https://github.com/calabash/run_loop/pull/757

A temporary solution is to use this WIP branch, although it is not great to have to use this as it is a draft PR. Xcode 12 support for Calabash will hopefully come in the future.

Change in your Gemfile

gem "run_loop"

to

gem 'run_loop', git: 'https://github.com/calabash/run_loop.git', branch: 'xcode_14_support'

iOS app 'The application could not be verified' only on one device

As I notice The application could not be verified. raise up because in your device there is already an app installed with the same bundle identifier.

I got this issue because in my device there is my app that download from App store. and i test its update Version from Xcode. And i used same identifier that is live app and my development testing app. So i just remove app-store Live app from my device and this error going to be fix.

Change Bootstrap tooltip color

We are using bootstrap 3.0 on our website, but none of the above steps worked in updating the styling of the tooltip. But I did find a solution using jQueryUI styling instead

https://jqueryui.com/tooltip/#custom-style

CSS

  .ui-tooltip, .arrow:after {
    background: black;
    border: 2px solid white;
  }
  .ui-tooltip {
    padding: 10px 20px;
    color: white;
    border-radius: 20px;
    font: bold 14px "Helvetica Neue", Sans-Serif;
    text-transform: uppercase;
    box-shadow: 0 0 7px black;
  }

HTML

<div class="qu_help" data-toggle="tooltip" title="Some Random Title"> 
   <span class="glyphicon glyphicon-question-sign" aria-hidden="true"></span>
</div>

I'm adding this answer in case someone else is in a similar situation as I was.

Entity Framework - Generating Classes

  1. Open the EDMX model
  2. Right click -> Update Model from Browser -> Stored Procedure -> Select your stored procedure -> Finish
  3. See the Model Browser popping up next to Solution Explorer.
  4. Go to Function Imports -> Right click on your Stored Procedure -> Add Function Import
  5. Select the Entities under Return a Collection of -> Select your Entity name from the drop down
  6. Build your Solution.

Powershell Get-ChildItem most recent file in directory

Yes I think this would be quicker.

Get-ChildItem $folder | Sort-Object -Descending -Property LastWriteTime -Top 1 

Bootstrap 3 Carousel fading to new slide instead of sliding to new slide

This can be accomplished using only CSS. To change the carousel to a fade transition instead of slide, use one of the following snippets (LESS or standard CSS).

LESS

// Fade transition for carousel items
.carousel {
  .item {
    left: 0 !important;
    .transition(opacity .4s); //adjust timing here
  }
  .carousel-control {
    background-image: none; // remove background gradients on controls
  }
  // Fade controls with items
  .next.left,
  .prev.right {
    opacity: 1;
    z-index: 1;
  }
  .active.left,
  .active.right {
    opacity: 0;
    z-index: 2;
  }
}

Plain CSS:

/* Fade transition for carousel items */
.carousel .item {
    left: 0 !important;
      -webkit-transition: opacity .4s; /*adjust timing here */
         -moz-transition: opacity .4s;
           -o-transition: opacity .4s;
              transition: opacity .4s;
}
.carousel-control {
    background-image: none !important; /* remove background gradients on controls */
}
/* Fade controls with items */
.next.left,
.prev.right {
    opacity: 1;
    z-index: 1;
}
.active.left,
.active.right {
    opacity: 0;
    z-index: 2;
}

Stream file using ASP.NET MVC FileContentResult in a browser with a name?

public FileContentResult GetImage(int productId) { 
     Product prod = repository.Products.FirstOrDefault(p => p.ProductID == productId); 
     if (prod != null) { 
         return File(prod.ImageData, prod.ImageMimeType); 
      } else { 
         return null; 
     } 
}

Intermediate language used in scalac?

The nearest equivalents would be icode and bcode as used by scalac, view Miguel Garcia's site on the Scalac optimiser for more information, here: http://magarciaepfl.github.io/scala/

You might also consider Java bytecode itself to be your intermediate representation, given that bytecode is the ultimate output of scalac.

Or perhaps the true intermediate is something that the JIT produces before it finally outputs native instructions?

Ultimately though... There's no single place that you can point at an claim "there's the intermediate!". Scalac works in phases that successively change the abstract syntax tree, every single phase produces a new intermediate. The whole thing is like an onion, and it's very hard to try and pick out one layer as somehow being more significant than any other.

How can I implement custom Action Bar with custom buttons in Android?

Please write following code in menu.xml file:

<menu xmlns:android="http://schemas.android.com/apk/res/android"
      xmlns:my_menu_tutorial_app="http://schemas.android.com/apk/res-auto"
      xmlns:tools="http://schemas.android.com/tools"
      tools:context="com.example.mymenus.menu_app.MainActivity">
<item android:id="@+id/item_one"
      android:icon="@drawable/menu_icon"
      android:orderInCategory="l01"
      android:title="Item One"
      my_menu_tutorial_app:showAsAction="always">
      <!--sub-menu-->
      <menu>
          <item android:id="@+id/sub_one"
                android:title="Sub-menu item one" />
          <item android:id="@+id/sub_two"
                android:title="Sub-menu item two" />
      </menu>

Also write this java code in activity class file:

public boolean onOptionsItemSelected(MenuItem item)
{
    super.onOptionsItemSelected(item);
    Toast.makeText(this, "Menus item selected: " +
        item.getTitle(), Toast.LENGTH_SHORT).show();
    switch (item.getItemId())
    {
        case R.id.sub_one:
            isItemOneSelected = true;
            supportInvalidateOptionsMenu();
            return true;
        case MENU_ITEM + 1:
            isRemoveItem = true;
            supportInvalidateOptionsMenu();
            return true;
        default:
            return false;
    }
}

This is the easiest way to display menus in action bar.

Best way to get value from Collection by index

use for each loop...

ArrayList<Character> al = new ArrayList<>();    
String input="hello";

for (int i = 0; i < input.length(); i++){
    al.add(input.charAt(i));
}

for (Character ch : al) {               
    System.Out.println(ch);             
}

How to re-create database for Entity Framework?

My solution is best suited for :
- deleted your mdf file
- want to re-create your db.

In order to recreate your database you need add the connection using Visual Studio.

Step 1 : Go to Server Explorer add new connection( or look for a add db icon).

Step 2 : Change Datasource to Microsoft SQL Server Database File.

Step 3 : add any database name you desire in the Database file name field.(preferably the same name you have in the web.config AttachDbFilename attribute)

Step 4 : click browse and navigate to where you will like it to be located.

Step 5 : in the package manager console run command update-database

Could not execute menu item (internal error)[Exception] - When changing PHP version from 5.3.1 to 5.2.9

The problem was the MySQL56 service was running and it has occupied the port of WAMP MySQL.After MySQL56 service stopped the WAMP server started successfully.

Equivalent VB keyword for 'break'

Exit [construct], and intelisense will tell you which one(s) are valid in a particular place.

How to select all records from one table that do not exist in another table?

Here's what worked best for me.

SELECT *
FROM @T1
EXCEPT
SELECT a.*
FROM @T1 a
JOIN @T2 b ON a.ID = b.ID

This was more than twice as fast as any other method I tried.

Git: how to reverse-merge a commit?

To revert a merge commit, you need to use: git revert -m <parent number>. So for example, to revert the recent most merge commit using the parent with number 1 you would use:

git revert -m 1 HEAD

To revert a merge commit before the last commit, you would do:

git revert -m 1 HEAD^

Use git show <merge commit SHA1> to see the parents, the numbering is the order they appear e.g. Merge: e4c54b3 4725ad2

git merge documentation: http://schacon.github.com/git/git-merge.html

git merge discussion (confusing but very detailed): http://schacon.github.com/git/howto/revert-a-faulty-merge.txt

Java array reflection: isArray vs. instanceof

There is no difference in behavior that I can find between the two (other than the obvious null-case). As for which version to prefer, I would go with the second. It is the standard way of doing this in Java.

If it confuses readers of your code (because String[] instanceof Object[] is true), you may want to use the first to be more explicit if code reviewers keep asking about it.

React Hook "useState" is called in function "app" which is neither a React function component or a custom React Hook function

React components (both functional as well as class) must begin with a capital letter. Like

const App=(props)=><div>Hey</div>

class App extends React.Component{
   render(){
     return <div>Hey</div>
   }
}

React identifies user-defined components by following this semantic. React's JSX transpiles to React.createElement function which returns an object representation of the dom node. The type property of this object tells whether it is a user-defined component or a dom element like div. Therefore it is important to follow this semantics

Since useState hook can only be used inside the functional component(or a custom hook) this is the reason why you are getting the error because react is not able to identify it as a user-defined component in the first place.

useState can also be used inside the custom hooks which is used for the reusability and the abstraction of logic. So according to the rules of hooks, the name of a custom hook must begin with a "use" prefix and must be in a camelCase

What's the difference between event.stopPropagation and event.preventDefault?

_x000D_
_x000D_
$("#but").click(function(event){_x000D_
console.log("hello");_x000D_
  event.preventDefault();_x000D_
 });_x000D_
_x000D_
_x000D_
$("#foo").click(function(){_x000D_
 alert("parent click event fired !");_x000D_
});
_x000D_
<script src="https://ajax.googleapis.com/ajax/libs/jquery/2.1.1/jquery.min.js"></script>_x000D_
<div id="foo">_x000D_
  <button id="but">button</button>_x000D_
</div>
_x000D_
_x000D_
_x000D_

ASP.NET: HTTP Error 500.19 – Internal Server Error 0x8007000d

I had this problem with a brand new web service. Solved it by adding read-only access for Everyone on Properties->Security for the folder that the service was in.

Unable to load script from assets index.android.bundle on windows

I think you don't have yarn installed try installing it with chocolatey or something. It should be installed before creating your project (react-native init command).

No need of creating assets directory.

Reply if it doesn't work.

Edit: In the recent version of react-native they have fixed it. If you want complete freedom from this just uninstall node (For complete uninstallation Completely remove node refer this link) and reinstall node, react-native-cli then create your new project.

iterate through a map in javascript

I'd use standard javascript:

for (var m in myMap){
    for (var i=0;i<myMap[m].length;i++){
    ... do something with myMap[m][i] ...
    }
} 

Note the different ways of treating objects and arrays.

What is the (function() { } )() construct in JavaScript?

Start here:

var b = 'bee';
console.log(b);  // global

Put it in a function and it is no longer global -- your primary goal.

function a() {
  var b = 'bee';
  console.log(b);
}
a();
console.log(b);  // ReferenceError: b is not defined -- *as desired*

Call the function immediately -- oops:

function a() {
  var b = 'bee';
  console.log(b);
}();             // SyntaxError: Expected () to start arrow function, but got ';' instead of '=>'

Use the parentheses to avoid a syntax error:

(function a() {
  var b = 'bee';
  console.log(b);
})(); // OK now

You can leave off the function name:

(function () {    // no name required
  var b = 'bee';
  console.log(b);
})();

It doesn't need to be any more complicated than that.

How to return a value from a Form in C#?

If you want to pass data to form2 from form1 without passing like new form(sting "data");

Do like that in form 1

using (Form2 form2= new Form2())
{
   form2.ReturnValue1 = "lalala";
   form2.ShowDialog();
}

in form 2 add

public string ReturnValue1 { get; set; }

private void form2_Load(object sender, EventArgs e)
{
   MessageBox.Show(ReturnValue1);
}

Also you can use value in form1 like this if you want to swap something in form1

just in form1

textbox.Text =form2.ReturnValue1

Fixing slow initial load for IIS

Writing a ping service/script to hit your idle website is rather a best way to go because you will have a complete control. Other options that you have mentioned would be available if you have leased a dedicated hosting box.

In a shared hosting space, warmup scripts are the best first level defense (self help is the best help). Here is an article which shares an idea on how to do it from your own web application.

Difference between EXISTS and IN in SQL?

EXISTS Is Faster in Performance than IN. If Most of the filter criteria is in subquery then better to use IN and If most of the filter criteria is in main query then better to use EXISTS.

What is the difference between XAMPP or WAMP Server & IIS?

In addition to the above, WAMP supports 64 bit PHP on Windows systems while XAMPP only offers 32 bit versions. This actually made me switch to WAMP on my Windows machine since you need 64 bit PHP 7 to get bigint numbers correctly from MySQL

Handling JSON Post Request in Go

I found the following example from the docs really helpful (source here).

package main

import (
    "encoding/json"
    "fmt"
    "io"
    "log"
    "strings"
)

func main() {
    const jsonStream = `
        {"Name": "Ed", "Text": "Knock knock."}
        {"Name": "Sam", "Text": "Who's there?"}
        {"Name": "Ed", "Text": "Go fmt."}
        {"Name": "Sam", "Text": "Go fmt who?"}
        {"Name": "Ed", "Text": "Go fmt yourself!"}
    `
    type Message struct {
        Name, Text string
    }
    dec := json.NewDecoder(strings.NewReader(jsonStream))
    for {
        var m Message
        if err := dec.Decode(&m); err == io.EOF {
            break
        } else if err != nil {
            log.Fatal(err)
        }
        fmt.Printf("%s: %s\n", m.Name, m.Text)
    }
}

The key here being that the OP was looking to decode

type test_struct struct {
    Test string
}

...in which case we would drop the const jsonStream, and replace the Message struct with the test_struct:

func test(rw http.ResponseWriter, req *http.Request) {
    dec := json.NewDecoder(req.Body)
    for {
        var t test_struct
        if err := dec.Decode(&t); err == io.EOF {
            break
        } else if err != nil {
            log.Fatal(err)
        }
        log.Printf("%s\n", t.Test)
    }
}

Update: I would also add that this post provides some great data about responding with JSON as well. The author explains struct tags, which I was not aware of.

Since JSON does not normally look like {"Test": "test", "SomeKey": "SomeVal"}, but rather {"test": "test", "somekey": "some value"}, you can restructure your struct like this:

type test_struct struct {
    Test string `json:"test"`
    SomeKey string `json:"some-key"`
}

...and now your handler will parse JSON using "some-key" as opposed to "SomeKey" (which you will be using internally).

Why does JSON.parse fail with the empty string?

As an empty string is not valid JSON it would be incorrect for JSON.parse('') to return null because "null" is valid JSON. e.g.

JSON.parse("null");

returns null. It would be a mistake for invalid JSON to also be parsed to null.

While an empty string is not valid JSON two quotes is valid JSON. This is an important distinction.

Which is to say a string that contains two quotes is not the same thing as an empty string.

JSON.parse('""');

will parse correctly, (returning an empty string). But

JSON.parse('');

will not.

Valid minimal JSON strings are

The empty object '{}'

The empty array '[]'

The string that is empty '""'

A number e.g. '123.4'

The boolean value true 'true'

The boolean value false 'false'

The null value 'null'

append option to select menu?

Something like this:

var option = document.createElement("option");
option.text = "Text";
option.value = "myvalue";
var select = document.getElementById("id-to-my-select-box");
select.appendChild(option);

nvm keeps "forgetting" node in new terminal session

If you have tried everything still no luck you can try this :_

1 -> Uninstall NVM

rm -rf ~/.nvm

2 -> Remove npm dependencies by following this

3 -> Install NVM

curl -o- https://raw.githubusercontent.com/creationix/nvm/v0.33.11/install.sh | bash

4 -> Set ~/.bash_profile configuration

Run sudo nano ~/.bash_profile

Copy and paste following this

export NVM_DIR="$HOME/.nvm"
[ -s "$NVM_DIR/nvm.sh" ] && \. "$NVM_DIR/nvm.sh"  # This loads nvm
[ -s "$NVM_DIR/bash_completion" ] && \. "$NVM_DIR/bash_completion"  # This loads nvm bash_completion

5 -> CONTROL + X save the changes

6 -> Run . ~/.bash_profile

7 -> Now you should have nvm installed on your machine, to install node run nvm install v7.8.0 this will be default node version or you can install any version of node

set environment variable in python script

You can add elements to your environment by using

os.environ['LD_LIBRARY_PATH'] = 'my_path'

and run subprocesses in a shell (that uses your os.environ) by using

subprocess.call('sqsub -np ' + var1 + '/homedir/anotherdir/executable', shell=True)

How exactly does the android:onClick XML attribute differ from setOnClickListener?

Supporting Ruivo's answer, yes you have to declare method as "public" to be able to use in Android's XML onclick - I am developing an app targeting from API Level 8 (minSdk...) to 16 (targetSdk...).

I was declaring my method as private and it caused error, just declaring it as public works great.

Uploading a file in Rails

Update 2018

While everything written below still holds true, Rails 5.2 now includes active_storage, which allows stuff like uploading directly to S3 (or other cloud storage services), image transformations, etc. You should check out the rails guide and decide for yourself what fits your needs.


While there are plenty of gems that solve file uploading pretty nicely (see https://www.ruby-toolbox.com/categories/rails_file_uploads for a list), rails has built-in helpers which make it easy to roll your own solution.

Use the file_field-form helper in your form, and rails handles the uploading for you:

<%= form_for @person do |f| %>
  <%= f.file_field :picture %>
<% end %>

You will have access in the controller to the uploaded file as follows:

uploaded_io = params[:person][:picture]
File.open(Rails.root.join('public', 'uploads', uploaded_io.original_filename), 'wb') do |file|
  file.write(uploaded_io.read)
end

It depends on the complexity of what you want to achieve, but this is totally sufficient for easy file uploading/downloading tasks. This example is taken from the rails guides, you can go there for further information: http://guides.rubyonrails.org/form_helpers.html#uploading-files

Finding modified date of a file/folder

Here's what worked for me:

$a = Get-ChildItem \\server\XXX\Received_Orders\*.* | Where{$_.LastWriteTime -ge (Get-Date).AddDays(-7)}
if ($a = (Get-ChildItem \\server\XXX\Received_Orders\*.* | Where{$_.LastWriteTime -gt (Get-Date).AddDays(-7)}  
#Im using the -gt switch instead of -ge
{}
Else
{
'STORE XXX HAS NOT RECEIVED ANY ORDERS IN THE PAST 7 DAYS'
}


$b = Get-ChildItem \\COMP NAME\Folder\*.* | Where{$_.LastWriteTime -ge (Get-Date).AddDays(-1)}
if ($b = (Get-ChildItem \\COMP NAME\TFolder\*.* | Where{$_.LastWriteTime -gt (Get-Date).AddDays(-1)))}
{}
Else
{
'STORE XXX DID NOT RUN ITS BACKUP LAST NIGHT'
}

`getchar()` gives the same output as the input string

There is an underlying buffer/stream that getchar() and friends read from. When you enter text, the text is stored in a buffer somewhere. getchar() can stream through it one character at a time. Each read returns the next character until it reaches the end of the buffer. The reason it's not asking you for subsequent characters is that it can fetch the next one from the buffer.

If you run your script and type directly into it, it will continue to prompt you for input until you press CTRL+D (end of file). If you call it like ./program < myInput where myInput is a text file with some data, it will get the EOF when it reaches the end of the input. EOF isn't a character that exists in the stream, but a sentinel value to indicate when the end of the input has been reached.

As an extra warning, I believe getchar() will also return EOF if it encounters an error, so you'll want to check ferror(). Example below (not tested, but you get the idea).

main() {
    int c;
    do {
        c = getchar();
        if (c == EOF && ferror()) {
            perror("getchar");
        }
        else {
            putchar(c);
        }
    }
    while(c != EOF);
}

Eclipse - debugger doesn't stop at breakpoint

One additional comment regarding Vineet Reynolds answer.

I found out that I had to set -XX:+UseParallelGC in eclipse.ini

I setup the virtual machine (vm) arguments as follows

-vmargs
-Dosgi.requiredJavaVersion=1.7
-Xms512m
-Xmx1024m
-XX:+UseParallelGC
-XX:PermSize=256M
-XX:MaxPermSize=512M

that solved the issue.

Boxplot in R showing the mean

Based on the answers by @James and @Jyotirmoy Bhattacharya I came up with this solution:

zx <- replicate (5, rnorm(50))
zx_means <- (colMeans(zx, na.rm = TRUE))
boxplot(zx, horizontal = FALSE, outline = FALSE)
points(zx_means, pch = 22, col = "darkgrey", lwd = 7)

(See this post for more details)

If you would like to add points to horizontal box plots, please see this post.

How to get file name when user select a file via <input type="file" />?

just tested doing this and it seems to work in firefox & IE

<html>
    <head>
        <script type="text/javascript">
            function alertFilename()
            {
                var thefile = document.getElementById('thefile');
                alert(thefile.value);
            }
        </script>
    </head>
    <body>
        <form>
            <input type="file" id="thefile" onchange="alertFilename()" />
            <input type="button" onclick="alertFilename()" value="alert" />
        </form>
    </body>
</html>

What does it mean when Statement.executeUpdate() returns -1?

For executeUpdate statements against a DB2 for z/OS server, the value that is returned depends on the type of SQL statement that is being executed:

For an SQL statement that can have an update count, such as an INSERT, UPDATE, or DELETE statement, the returned value is the number of affected rows. It can be:

A positive number, if a positive number of rows are affected by the operation, and the operation is not a mass delete on a segmented table space.

0, if no rows are affected by the operation.

-1, if the operation is a mass delete on a segmented table space.

For a DB2 CALL statement, a value of -1 is returned, because the DB2 database server cannot determine the number of affected rows. Calls to getUpdateCount or getMoreResults for a CALL statement also return -1. For any other SQL statement, a value of -1 is returned.

PHP - Get array value with a numeric index

I am proposing my idea about it against any disadvantages array_values( ) function, because I think that is not a direct get function. In this way it have to create a copy of the values numerically indexed array and then access. If PHP does not hide a method that automatically translates an integer in the position of the desired element, maybe a slightly better solution might consist of a function that runs the array with a counter until it leads to the desired position, then return the element reached.

So the work would be optimized for very large array of sizes, since the algorithm would be best performing indices for small, stopping immediately. In the solution highlighted of array_values( ), however, it has to do with a cycle flowing through the whole array, even if, for e.g., I have to access $ array [1].

function array_get_by_index($index, $array) {

    $i=0;
    foreach ($array as $value) {
        if($i==$index) {
            return $value;
        }
        $i++;
    }
    // may be $index exceedes size of $array. In this case NULL is returned.
    return NULL;
}

Breaking out of a for loop in Java

How about

for (int k = 0; k < 10; k = k + 2) {
    if (k == 2) {
        break;
    }

    System.out.println(k);
}

The other way is a labelled loop

myloop:  for (int i=0; i < 5; i++) {

              for (int j=0; j < 5; j++) {

                if (i * j > 6) {
                  System.out.println("Breaking");
                  break myloop;
                }

                System.out.println(i + " " + j);
              }
          }

For an even better explanation you can check here

IE11 meta element Breaks SVG

It sounds as though you're not in a modern document mode. Internet Explorer 11 shows the SVG just fine when you're in Standards Mode. Make sure that if you have an x-ua-compatible meta tag, you have it set to Edge, rather than an earlier mode.

<meta http-equiv="X-UA-Compatible" content="IE=edge">

You can determine your document mode by opening up your F12 Developer Tools and checking either the document mode dropdown (seen at top-right, currently "Edge") or the emulation tab:

enter image description here

If you do not have an x-ua-compatible meta tag (or header), be sure to use a doctype that will put the document into Standards mode, such as <!DOCTYPE html>.

enter image description here

How do I generate a random int number?

 int n = new Random().Next();

You can also give minimum and maximum value to Next() function. Like:

 int n = new Random().Next(5, 10);

Moving items around in an ArrayList

To Move item in list simply add:

// move item to index 0
Object object = ObjectList.get(index);
ObjectList.remove(index);
ObjectList.add(0,object);

To Swap two items in list simply add:

// swap item 10 with 20
Collections.swap(ObjectList,10,20);

ValueError: unconverted data remains: 02:05

  timeobj = datetime.datetime.strptime(my_time, '%Y-%m-%d %I:%M:%S')
  File "/usr/lib/python2.7/_strptime.py", line 335, in _strptime
    data_string[found.end():])
ValueError: unconverted data remains:

In my case, the problem was an extra space in the input date string. So I used strip() and it started to work.

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

hdpi 480x800 px Samsung S2

xhdpi 720x1280 px - Nexus 4 phone - 4.7,4.8 inches Samsung Galaxy S3 Motorola Moto G

xxhdpi 1080x1920 px - Nexus 5 phone - 4.95 inches Samsung Galaxy S4 Samsung Galaxy S5 Samsung Galaxy Note 3 - 5.7 inches LG G2 HTC One M8 HTC One M9 Sony Xperia Z1
Sony Xperia Z2 Sony Xperia Z3 Sony Xperia Z3+

xxxhdpi 1440x2560 px - Nexus 6 phablet - 6 inches Samsung S6 Samsung S6 Edge Samsung Galaxy Note 4 - 5.7 inches LG G3
LG G4

xxhdpi 1920×1200 px - Nexus 7 tablet - 7 inches Sony Z3 Tablet Compact LG G Pad 8.3 - 8.3 inches Sony Xperia Z2 Tablet - 10.1 inches

xxxhdpi 2560×1600 px - Nexus 10 tablet - 10.1 inches ~Google Nexus 9 Sony Xperia Z4 tablet Samsung Galaxy Note Pro 12.2 Samsung Galaxy Note 10.1 Samsung Galaxy Tab S 10.5 Dell Venue 8 7840

how to configure config.inc.php to have a loginform in phpmyadmin

$cfg['Servers'][$i]['auth_type'] = 'cookie';

should work.

From the manual:

auth_type = 'cookie' prompts for a MySQL username and password in a friendly HTML form. This is also the only way by which one can log in to an arbitrary server (if $cfg['AllowArbitraryServer'] is enabled). Cookie is good for most installations (default in pma 3.1+), it provides security over config and allows multiple users to use the same phpMyAdmin installation. For IIS users, cookie is often easier to configure than http.

Update .NET web service to use TLS 1.2

PowerBI Embedded requires TLS 1.2.

The answer above by Etienne Faucher is your solution. quick link to above answer... quick link to above answer... ( https://stackoverflow.com/a/45442874 )

PowerBI Requires TLS 1.2 June 2020 - This Is your Answer - Consider Forcing your IIS runtime to get up to 4.6 to force the default TLS 1.2 behavior you are looking for from the framework. The above answer gives you a config change only solution.

Symptoms: Forced Closed Rejected TCP/IP Connection to Microsoft PowerBI Embedded that just shows up all of a sudden across your systems.

These PowerBI Calls just stop working with a Hard TCP/IP Close error like a firewall would block a connection. Usually the auth steps work - it is when you hit the service for specific workspace and report id's that it fails.

This is the 2020 note from Microsoft PowerBI about TLS 1.2 required

PowerBIClient

methods that show this problem

GetReportsInGroupAsync GetReportsInGroupAsAdminAsync GetReportsAsync GetReportsAsAdminAsync Microsoft.PowerBI.Api HttpClientHandler Force TLS 1.1 TLS 1.2

Search Error Terms to help people find this: System.Net.Http.HttpRequestException: An error occurred while sending the request System.Net.WebException: The underlying connection was closed: An unexpected error occurred on a send. System.IO.IOException: Unable to read data from the transport connection: An existing connection was forcibly closed by the remote host.

Add a property to a JavaScript object using a variable as the name?

ajavascript have two type of annotation for fetching javascript Object properties:

Obj = {};

1) (.) annotation eg. Obj.id this will only work if the object already have a property with name 'id'

2) ([]) annotation eg . Obj[id] here if the object does not have any property with name 'id',it will create a new property with name 'id'.

so for below example:

A new property will be created always when you write Obj[name]. And if the property already exist with the same name it will override it.

const obj = {}
    jQuery(itemsFromDom).each(function() {
      const element = jQuery(this)
      const name = element.attr('id')
      const value = element.attr('value')
      // This will work
      obj[name]= value;
    })

How to add System.Windows.Interactivity to project?

I got it via the Prism.WPF NuGet-Package. (it includes Windows.System.Interactivity)

How can I search Git branches for a file or directory?

You could use gitk --all and search for commits "touching paths" and the pathname you are interested in.

How to convert image into byte array and byte array to base64 String in android?

They have wrapped most stuff need to solve your problem, one of the tests looks like this:

String filename = CSSURLEmbedderTest.class.getResource("folder.png").getPath().replace("%20", " ");
String code = "background: url(folder.png);";

StringWriter writer = new StringWriter();
embedder = new CSSURLEmbedder(new StringReader(code), true);
embedder.embedImages(writer, filename.substring(0, filename.lastIndexOf("/")+1));

String result = writer.toString();
assertEquals("background: url(" + folderDataURI + ");", result);

Operator overloading ==, !=, Equals

public class BOX
{
    double height, length, breadth;

    public static bool operator == (BOX b1, BOX b2)
    {
        if (b1 is null)
            return b2 is null;

        return b1.Equals(b2);
    }

    public static bool operator != (BOX b1, BOX b2)
    {
        return !(b1 == b2);
    }

    public override bool Equals(object obj)
    {
        if (obj == null)
            return false;

        return obj is BOX b2? (length == b2.length && 
                               breadth == b2.breadth && 
                               height == b2.height): false;

    }

    public override int GetHashCode()
    {
        return (height,length,breadth).GetHashCode();
    }
}

How to format a JavaScript date

Sugar.js has excellent extensions to the Date object, including a Date.format method.

Examples from the documentation:

Date.create().format('{Weekday} {Month} {dd}, {yyyy}');

Date.create().format('{12hr}:{mm}{tt}')

How to send value attribute from radio button in PHP

The radio buttons are sent on form submit when they are checked only...

use isset() if true then its checked otherwise its not

How to set cursor position in EditText?

EditText editText = findViewById(R.id.editText);
editText.setSelection(editText.getText().length());

JAVA_HOME should point to a JDK not a JRE

In addition to sovas' response on how to add the JAVA_HOME variable, if it was working before and stopped working, ensure that the path still exists. I updated Java recently which deleted the old version, invalidating my JAVA_HOME environment variable.

click command in selenium webdriver does not work

Thanks for all the answers everyone! I have found a solution, turns out I didn't provide enough code in my question.

The problem was NOT with the click() function after all, but instead related to cas authentication used with my project. In Selenium IDE my login test executed a "open" command to the following location,

/cas/login?service=https%1F%8FAPPNAME%2FMOREURL%2Fj_spring_cas_security

That worked. I exported the test to Selenium webdriver which naturally preserved that location. The command in Selenium Webdriver was,

driver.get(baseUrl + "/cas/login?service=https%1A%2F%8FAPPNAME%2FMOREURL%2Fj_spring_cas_security");

For reasons I have yet to understand the above failed. When I changed it to,

driver.get(baseUrl + "MOREURL/");

The click command suddenly started to work... I will edit this answer if I can figure out why exactly this is.

Note: I obscured the URLs used above to protect my company's product.

How to fix git error: RPC failed; curl 56 GnuTLS

You can set some option to resolve the issue

Either at global level: (needed if you clone, don't forget to reset after)

$ git config --global http.sslVerify false
$ git config --global http.postBuffer 1048576000

or on a local repository

$ git config http.sslVerify false
$ git config http.postBuffer 1048576000

Multiline input form field using Bootstrap

I think the problem is that you are using type="text" instead of textarea. What you want is:

<textarea class="span6" rows="3" placeholder="What's up?" required></textarea>

To clarify, a type="text" will always be one row, where-as a textarea can be multiple.

Get user profile picture by Id

Through the Javascript SDK (v2.12 - April, 2017) you can get the details of the picture request this way:

FB.api("/" + uid + "/picture?redirect=0", function (response) {
  console.log(response);

  // prints the following:
  //data: {
  //  height: 50
  //  is_silhouette: false
  //  url: "https://lookaside.facebook.com/platform/profilepic/?asid=…&height=50&width=50&ext=…&hash…"
  //  width: 50
  //}

  if (response && !response.error) {
    // change the src attribute of img elements
    [...document.getElementsByClassName('fb-user-img')].forEach(
      i => i.src = response.data.url
    );

    // OR redirect to the URL above
    location.assign(response.data.url);
  }
});

For getting the JSON response the parameter redirect with 0 (zero) as value is important since the request redirects to the image by default. You may still add other parameters in the same URL. Examples:

  • "/" + uid + "/picture?redirect=0&width=100&height=100": a 100x100 image will be returned;
  • "/" + uid + "/picture?redirect=0&type=large": a 200x200 image is returned. Other possible type values include: small, normal, album, and square.

How to switch between frames in Selenium WebDriver using Java

to switchto a frame:

driver.switchTo.frame("Frame_ID");

to switch to the default again.

driver.switchTo().defaultContent();

How can you dynamically create variables via a while loop?

Unless there is an overwhelming need to create a mess of variable names, I would just use a dictionary, where you can dynamically create the key names and associate a value to each.

a = {}
k = 0
while k < 10:
    <dynamically create key> 
    key = ...
    <calculate value> 
    value = ...
    a[key] = value 
    k += 1

There are also some interesting data structures in the new 'collections' module that might be applicable:

http://docs.python.org/dev/library/collections.html

File Upload using AngularJS

You may consider IaaS for file upload, such as Uploadcare. There is an Angular package for it: https://github.com/uploadcare/angular-uploadcare

Technically it's implemented as a directive, providing different options for uploading, and manipulations for uploaded images within the widget:

<uploadcare-widget
  ng-model="object.image.info.uuid"
  data-public-key="YOURKEYHERE"
  data-locale="en"
  data-tabs="file url"
  data-images-only="true"
  data-path-value="true"
  data-preview-step="true"
  data-clearable="true"
  data-multiple="false"
  data-crop="400:200"
  on-upload-complete="onUCUploadComplete(info)"
  on-widget-ready="onUCWidgetReady(widget)"
  value="{{ object.image.info.cdnUrl }}"
 />

More configuration options to play with: https://uploadcare.com/widget/configure/

reading from app.config file

Try:

string value = ConfigurationManager.AppSettings[key];

For more details check: Reading Keys from App.Config

How to get the cell value by column name not by index in GridView in asp.net

GridView does not act as column names, as that's it's datasource property to know those things.

If you still need to know the index given a column name, then you can create a helper method to do this as the gridview Header normally contains this information.

int GetColumnIndexByName(GridViewRow row, string columnName)
{
    int columnIndex = 0;
    foreach (DataControlFieldCell cell in row.Cells)
    {
        if (cell.ContainingField is BoundField)
            if (((BoundField)cell.ContainingField).DataField.Equals(columnName))
                break;
        columnIndex++; // keep adding 1 while we don't have the correct name
    }
    return columnIndex;
}

remember that the code above will use a BoundField... then use it like:

protected void GridView_RowDataBound(object sender, GridViewRowEventArgs e)
{
    if (e.Row.RowType == DataControlRowType.DataRow)
    {
        int index = GetColumnIndexByName(e.Row, "myDataField");
        string columnValue = e.Row.Cells[index].Text;
    }
}

I would strongly suggest that you use the TemplateField to have your own controls, then it's easier to grab those controls like:

<asp:GridView ID="gv" runat="server">
    <Columns>
        <asp:TemplateField>
            <ItemTemplate>
                <asp:Label ID="lblName" runat="server" Text='<%# Eval("Name") %>' />
            </ItemTemplate>
        </asp:TemplateField>
    </Columns>
</asp:GridView>

and then use

string columnValue = ((Label)e.Row.FindControl("lblName")).Text;

jQuery: count number of rows in a table

Here's my take on it:

//Helper function that gets a count of all the rows <TR> in a table body <TBODY>
$.fn.rowCount = function() {
    return $('tr', $(this).find('tbody')).length;
};

USAGE:

var rowCount = $('#productTypesTable').rowCount();

How to use session in JSP pages to get information?

Suppose you want to use, say ID in any other webpage then you can do it by following code snippet :

String id=(String)session.getAttribute("uid");

Here uid is the attribute in which you have stored the ID earlier. You can set it by:

session.setAttribute("uid",id);

Should try...catch go inside or outside a loop?

That depends on the failure handling. If you just want to skip the error elements, try inside:

for(int i = 0; i < max; i++) {
    String myString = ...;
    try {
        float myNum = Float.parseFloat(myString);
        myFloats[i] = myNum;
    } catch (NumberFormatException ex) {
        --i;
    }
}

In any other case i would prefer the try outside. The code is more readable, it is more clean. Maybe it would be better to throw an IllegalArgumentException in the error case instead if returning null.

Read a zipped file as a pandas DataFrame

For "zip" files, you can use import zipfile and your code will be working simply with these lines:

import zipfile
import pandas as pd
with zipfile.ZipFile("Crime_Incidents_in_2013.zip") as z:
   with z.open("Crime_Incidents_in_2013.csv") as f:
      train = pd.read_csv(f, header=0, delimiter="\t")
      print(train.head())    # print the first 5 rows

And the result will be:

X,Y,CCN,REPORT_DAT,SHIFT,METHOD,OFFENSE,BLOCK,XBLOCK,YBLOCK,WARD,ANC,DISTRICT,PSA,NEIGHBORHOOD_CLUSTER,BLOCK_GROUP,CENSUS_TRACT,VOTING_PRECINCT,XCOORD,YCOORD,LATITUDE,LONGITUDE,BID,START_DATE,END_DATE,OBJECTID
0  -77.054968548763071,38.899775938598317,0925135...                                                                                                                                                               
1  -76.967309569035052,38.872119553647011,1003352...                                                                                                                                                               
2  -76.996184958456539,38.927921847721443,1101010...                                                                                                                                                               
3  -76.943077541353617,38.883686046653935,1104551...                                                                                                                                                               
4  -76.939209158039446,38.892278093281632,1125028...

Javascript checkbox onChange

I know this seems like noob answer but I'm putting it here so that it can help others in the future.

Suppose you are building a table with a foreach loop. And at the same time adding checkboxes at the end.

<!-- Begin Loop-->
<tr>
 <td><?=$criteria?></td>
 <td><?=$indicator?></td>
 <td><?=$target?></td>
 <td>
   <div class="form-check">
    <input type="checkbox" class="form-check-input" name="active" value="<?=$id?>" <?=$status?'checked':''?>> 
<!-- mark as 'checked' if checkbox was selected on a previous save -->
   </div>
 </td>
</tr>
<!-- End of Loop -->

You place a button below the table with a hidden input:

<form method="post" action="/goalobj-review" id="goalobj">

 <!-- we retrieve saved checkboxes & concatenate them into a string separated by commas.i.e. $saved_data = "1,2,3"; -->

 <input type="hidden" name="result" id="selected" value="<?= $saved_data ?>>
 <button type="submit" class="btn btn-info" form="goalobj">Submit Changes</button>
</form>

You can write your script like so:

<script type="text/javascript">
    var checkboxes = document.getElementsByClassName('form-check-input');
    var i;
    var tid = setInterval(function () {
        if (document.readyState !== "complete") {
            return;
        }
        clearInterval(tid);
    for(i=0;i<checkboxes.length;i++){
        checkboxes[i].addEventListener('click',checkBoxValue);
    }
    },100);

    function checkBoxValue(event) {
        var selected = document.querySelector("input[id=selected]");
        var result = 0;
        if(this.checked) {

            if(selected.value.length > 0) {
                result = selected.value + "," + this.value;
                document.querySelector("input[id=selected]").value = result;
            } else {
                result = this.value;
                document.querySelector("input[id=selected]").value = result;
            }
        }
        if(! this.checked) { 

// trigger if unchecked. if checkbox is marked as 'checked' from a previous saved is deselected, this will also remove its corresponding value from our hidden input.

            var compact = selected.value.split(","); // split string into array
            var index = compact.indexOf(this.value); // return index of our selected checkbox
            compact.splice(index,1); // removes 1 item at specified index
            var newValue = compact.join(",") // returns a new string
            document.querySelector("input[id=selected]").value = newValue;
        }

    }
</script>

The ids of your checkboxes will be submitted as a string "1,2" within the result variable. You can then break it up at the controller level however you want.

Reading file line by line (with space) in Unix Shell scripting - Issue

Try this,

IFS=''
while read line
do
    echo $line
done < file.txt

EDIT:

From man bash

IFS - The Internal Field Separator that is used for word
splitting after expansion and to split lines into words
with  the  read  builtin  command. The default value is
``<space><tab><newline>''

JavaScript ES6 promise for loop

If you are limited to ES6, the best option is Promise all. Promise.all(array) also returns an array of promises after successfully executing all the promises in array argument. Suppose, if you want to update many student records in the database, the following code demonstrates the concept of Promise.all in such case-

let promises = students.map((student, index) => {
//where students is a db object
student.rollNo = index + 1;
student.city = 'City Name';
//Update whatever information on student you want
return student.save();
});
Promise.all(promises).then(() => {
  //All the save queries will be executed when .then is executed
  //You can do further operations here after as all update operations are completed now
});

Map is just an example method for loop. You can also use for or forin or forEach loop. So the concept is pretty simple, start the loop in which you want to do bulk async operations. Push every such async operation statement in an array declared outside the scope of that loop. After the loop completes, execute the Promise all statement with the prepared array of such queries/promises as argument.

The basic concept is that the javascript loop is synchronous whereas database call is async and we use push method in loop that is also sync. So, the problem of asynchronous behavior doesn't occur inside the loop.

MongoDB: update every document on one field

This code will be helpful for you

        Model.update({
            'type': "newuser"
        }, {
            $set: {
                email: "[email protected]",
                phoneNumber:"0123456789"
            }
        }, {
            multi: true
        },
        function(err, result) {
            console.log(result);
            console.log(err);
        })  

Programmatically navigate using React router

React-Router 5.1.0+ Answer (using hooks and React >16.8)

You can use the new useHistory hook on Functional Components and Programmatically navigate:

import { useHistory } from "react-router-dom";

function HomeButton() {
  let history = useHistory();
  // use history.push('/some/path') here
};

React-Router 4.0.0+ Answer

In 4.0 and above, use the history as a prop of your component.

class Example extends React.Component {
   // use `this.props.history.push('/some/path')` here
};

NOTE: this.props.history does not exist in the case your component was not rendered by <Route>. You should use <Route path="..." component={YourComponent}/> to have this.props.history in YourComponent

React-Router 3.0.0+ Answer

In 3.0 and above, use the router as a prop of your component.

class Example extends React.Component {
   // use `this.props.router.push('/some/path')` here
};

React-Router 2.4.0+ Answer

In 2.4 and above, use a higher order component to get the router as a prop of your component.

import { withRouter } from 'react-router';

class Example extends React.Component {
   // use `this.props.router.push('/some/path')` here
};

// Export the decorated class
var DecoratedExample = withRouter(Example);

// PropTypes
Example.propTypes = {
  router: React.PropTypes.shape({
    push: React.PropTypes.func.isRequired
  }).isRequired
};

React-Router 2.0.0+ Answer

This version is backwards compatible with 1.x so there's no need to an Upgrade Guide. Just going through the examples should be good enough.

That said, if you wish to switch to the new pattern, there's a browserHistory module inside the router that you can access with

import { browserHistory } from 'react-router'

Now you have access to your browser history, so you can do things like push, replace, etc... Like:

browserHistory.push('/some/path')

Further reading: Histories and Navigation


React-Router 1.x.x Answer

I will not go into upgrading details. You can read about that in the Upgrade Guide

The main change about the question here is the change from Navigation mixin to History. Now it's using the browser historyAPI to change route so we will use pushState() from now on.

Here's an exemple using Mixin:

var Example = React.createClass({
  mixins: [ History ],
  navigateToHelpPage () {
    this.history.pushState(null, `/help`);
  }
})

Note that this History comes from rackt/history project. Not from React-Router itself.

If you don't want to use Mixin for some reason (maybe because of ES6 class), then you can access the history that you get from the router from this.props.history. It will be only accessible for the components rendered by your Router. So, if you want to use it in any child components it needs to be passed down as an attribute via props.

You can read more about the new release at their 1.0.x documentation

Here is a help page specifically about navigating outside your component

It recommends grabbing a reference history = createHistory() and calling replaceState on that.

React-Router 0.13.x Answer

I got into the same problem and could only find the solution with the Navigation mixin that comes with react-router.

Here's how I did it

import React from 'react';
import {Navigation} from 'react-router';

let Authentication = React.createClass({
  mixins: [Navigation],

  handleClick(e) {
    e.preventDefault();

    this.transitionTo('/');
  },

  render(){
    return (<div onClick={this.handleClick}>Click me!</div>);
  }
});

I was able to call transitionTo() without the need to access .context

Or you could try the fancy ES6 class

import React from 'react';

export default class Authentication extends React.Component {
  constructor(props) {
    super(props);
    this.handleClick = this.handleClick.bind(this);
  }

  handleClick(e) {
    e.preventDefault();

    this.context.router.transitionTo('/');
  }

  render(){
    return (<div onClick={this.handleClick}>Click me!</div>);
  }
}

Authentication.contextTypes = {
  router: React.PropTypes.func.isRequired
};

React-Router-Redux

Note: if you're using Redux, there is another project called React-Router-Redux that gives you redux bindings for ReactRouter, using somewhat the same approach that React-Redux does

React-Router-Redux has a few methods available that allow for simple navigating from inside action creators. These can be particularly useful for people that have existing architecture in React Native, and they wish to utilize the same patterns in React Web with minimal boilerplate overhead.

Explore the following methods:

  • push(location)
  • replace(location)
  • go(number)
  • goBack()
  • goForward()

Here is an example usage, with Redux-Thunk:

./actioncreators.js

import { goBack } from 'react-router-redux'

export const onBackPress = () => (dispatch) => dispatch(goBack())

./viewcomponent.js

<button
  disabled={submitting}
  className="cancel_button"
  onClick={(e) => {
    e.preventDefault()
    this.props.onBackPress()
  }}
>
  CANCEL
</button>

Install Windows Service created in Visual Studio

You need to open the Service.cs file in the designer, right click it and choose the menu-option "Add Installer".

It won't install right out of the box... you need to create the installer class first.

Some reference on service installer:

How to: Add Installers to Your Service Application

Quite old... but this is what I am talking about:

Windows Services in C#: Adding the Installer (part 3)

By doing this, a ProjectInstaller.cs will be automaticaly created. Then you can double click this, enter the designer, and configure the components:

  • serviceInstaller1 has the properties of the service itself: Description, DisplayName, ServiceName and StartType are the most important.

  • serviceProcessInstaller1 has this important property: Account that is the account in which the service will run.

For example:

this.serviceProcessInstaller1.Account = ServiceAccount.LocalSystem;

LINQ Using Max() to select a single row

You can also do:

(from u in table
orderby u.Status descending
select u).Take(1);

DateTime.TryParseExact() rejecting valid formats

This is the Simple method, Use ParseExact

CultureInfo provider = CultureInfo.InvariantCulture;
DateTime result;
String dateString = "Sun 08 Jun 2013 8:30 AM -06:00";
String format = "ddd dd MMM yyyy h:mm tt zzz";
result = DateTime.ParseExact(dateString, format, provider);

This should work for you.

How to read file using NPOI

private static ISheet GetFileStream(string fullFilePath)
    {
        var fileExtension = Path.GetExtension(fullFilePath);
        string sheetName;
        ISheet sheet = null;
        switch (fileExtension)
        {
            case ".xlsx":
                using (var fs = new FileStream(fullFilePath, FileMode.Open, FileAccess.Read))
                {
                    var wb = new XSSFWorkbook(fs);
                    sheetName = wb.GetSheetAt(0).SheetName;
                    sheet = (XSSFSheet) wb.GetSheet(sheetName);
                }
                break;
            case ".xls":
                using (var fs = new FileStream(fullFilePath, FileMode.Open, FileAccess.Read))
                {
                    var wb = new HSSFWorkbook(fs);
                    sheetName = wb.GetSheetAt(0).SheetName;
                    sheet = (HSSFSheet) wb.GetSheet(sheetName);
                }
                break;
        }
        return sheet;
    }

    private static DataTable GetRequestsDataFromExcel(string fullFilePath)
    {
        try
        {
            var sh = GetFileStream(fullFilePath);
            var dtExcelTable = new DataTable();
            dtExcelTable.Rows.Clear();
            dtExcelTable.Columns.Clear();
            var headerRow = sh.GetRow(0);
            int colCount = headerRow.LastCellNum;
            for (var c = 0; c < colCount; c++)
                dtExcelTable.Columns.Add(headerRow.GetCell(c).ToString());
            var i = 1;
            var currentRow = sh.GetRow(i);
            while (currentRow != null)
            {
                var dr = dtExcelTable.NewRow();
                for (var j = 0; j < currentRow.Cells.Count; j++)
                {
                    var cell = currentRow.GetCell(j);

                    if (cell != null)
                        switch (cell.CellType)
                        {
                            case CellType.Numeric:
                                dr[j] = DateUtil.IsCellDateFormatted(cell)
                                    ? cell.DateCellValue.ToString(CultureInfo.InvariantCulture)
                                    : cell.NumericCellValue.ToString(CultureInfo.InvariantCulture);
                                break;
                            case CellType.String:
                                dr[j] = cell.StringCellValue;
                                break;
                            case CellType.Blank:
                                dr[j] = string.Empty;
                                break;
                        }
                }
                dtExcelTable.Rows.Add(dr);
                i++;
                currentRow = sh.GetRow(i);
            }
            return dtExcelTable;
        }
        catch (Exception e)
        {
            throw;
        }
    }

JsonMappingException: No suitable constructor found for type [simple type, class ]: can not instantiate from JSON object

When I ran into this problem, it was a result of trying to use an inner class to serve as the DO. Construction of the inner class (silently) required an instance of the enclosing class -- which wasn't available to Jackson.

In this case, moving the inner class to its own .java file fixed the problem.

Converting stream of int's to char's in java

maybe not the fastest one:

//for example there is an integer with the value of 5:
int i = 5;

//getting the char '5' out of it:
char c = String.format("%s",i).charAt(0); 

Why is my toFixed() function not working?

Your conversion data is response[25] and follow the below steps.

var i = parseFloat(response[25]).toFixed(2)
console.log(i)//-6527.34

Upgrade to python 3.8 using conda

You can update your python version to 3.8 in conda using the command

conda install -c anaconda python=3.8

as per https://anaconda.org/anaconda/python. Though not all packages support 3.8 yet, running

conda update --all

may resolve some dependency failures. You can also create a new environment called py38 using this command

conda create -n py38 python=3.8

Edit - note that the conda install option will potentially take a while to solve the environment, and if you try to abort this midway through you will lose your Python installation (usually this means it will resort to non-conda pre-installed system Python installation).