Why am I not getting a java.util.ConcurrentModificationException in this example?

I had that same problem but in case that I was adding en element into iterated list. I made it this way

public static void remove(Integer remove) {
    for(int i=0; i<integerList.size(); i++) {
        //here is maybe fine to deal with integerList.get(i)==null
        if(integerList.get(i).equals(remove)) {                
            integerList.remove(i);
        }
    }
}

Now everything goes fine because you don't create any iterator over your list, you iterate over it "manually". And condition i < integerList.size() will never fool you because when you remove/add something into List size of the List decrement/increment..

Hope it helps, for me that was solution.

Why is a ConcurrentModificationException thrown and how to debug it

Try either CopyOnWriteArrayList or CopyOnWriteArraySet depending on what you are trying to do.

How do I import a specific version of a package using go get?

Go 1.11 will have a feature called go modules and you can simply add a dependency with a version. Follow these steps:

go mod init .
go mod edit -require github.com/wilk/[email protected]
go get -v -t ./...   
go build
go install

Here's more info on that topic - https://github.com/golang/go/wiki/Modules

bundle install returns "Could not locate Gemfile"

I had this problem on Ubuntu 18.04. I updated the gem

sudo gem install rails
sudo gem install jekyll
sudo gem install jekyll bundler
cd ~/desiredFolder
jekyll new <foldername>
cd <foldername> OR 
bundle init
bundle install
bundle add jekyll
bundle exec jekyll serve

All worked and goto your browser just go to http://127.0.0.1:4000/ and it really should be running

Changing the size of a column referenced by a schema-bound view in SQL Server

The views are probably created using the WITH SCHEMABINDING option and this means they are explicitly wired up to prevent such changes. Looks like the schemabinding worked and prevented you from breaking those views, lucky day, heh? Contact your database administrator and ask him to do the change, after it asserts the impact on the database.

From MSDN:

SCHEMABINDING

Binds the view to the schema of the underlying table or tables. When SCHEMABINDING is specified, the base table or tables cannot be modified in a way that would affect the view definition. The view definition itself must first be modified or dropped to remove dependencies on the table that is to be modified.

Refreshing Web Page By WebDriver When Waiting For Specific Condition

One important thing to note is that the driver.navigate().refresh() call sometimes seems to be asynchronous, meaning it does not wait for the refresh to finish, it just "kicks off the refresh" and doesn't block further execution while the browser is reloading the page.

While this only seems to happen in a minority of cases, we figured that it's better to make sure this works 100% by adding a manual check whether the page really started reloading.

Here's the code I wrote for that in our base page object class:

public void reload() {
    // remember reference to current html root element
    final WebElement htmlRoot = getDriver().findElement(By.tagName("html"));

    // the refresh seems to sometimes be asynchronous, so this sometimes just kicks off the refresh,
    // but doesn't actually wait for the fresh to finish
    getDriver().navigate().refresh();

    // verify page started reloading by checking that the html root is not present anymore
    final long startTime = System.currentTimeMillis();
    final long maxLoadTime = TimeUnit.SECONDS.toMillis(getMaximumLoadTime());
    boolean startedReloading = false;
    do {
        try {
            startedReloading = !htmlRoot.isDisplayed();
        } catch (ElementNotVisibleException | StaleElementReferenceException ex) {
            startedReloading = true;
        }
    } while (!startedReloading && (System.currentTimeMillis() - startTime < maxLoadTime));

    if (!startedReloading) {
        throw new IllegalStateException("Page " + getName() + " did not start reloading in " + maxLoadTime + "ms");
    }

    // verify page finished reloading
    verify();
}

Some notes:

Since you're reloading the page, you can't just check existence of a given element, because the element will be there before the reload starts and after it's done as well. So sometimes you might get true, but the page didn't even start loading yet.
When the page reloads, checking WebElement.isDisplayed() will throw a StaleElementReferenceException. The rest is just to cover all bases
getName(): internal method that gets the name of the page
getMaximumLoadTime(): internal method that returns how long page should be allowed to load in seconds
verify(): internal method makes sure the page actually loaded

Again, in a vast majority of cases, the do/while loop runs a single time because the code beyond navigate().refresh() doesn't get executed until the browser actually reloaded the page completely, but we've seen cases where it actually takes seconds to get through that loop because the navigate().refresh() didn't block until the browser finished loading.

Make content horizontally scroll inside a div

Same as what clairesuzy answered, except you can get a similar result by adding display: flex instead of white-space: nowrap. Using display: flex will collapse the img "margins", in case that behavior is preferred.

TypeError: $.ajax(...) is not a function?

Don't use the slim build of jQuery, which doesn't have the ajax function in it. Use the full version instead from https://jquery.com/download/

Note: Make sure to not use the jquery link copied from Bootstrap website, because they use the slim version.

Appending items to a list of lists in python

Python lists are mutable objects and here:

plot_data = [[]] * len(positions)

you are repeating the same list len(positions) times.

>>> plot_data = [[]] * 3
>>> plot_data
[[], [], []]
>>> plot_data[0].append(1)
>>> plot_data
[[1], [1], [1]]
>>>

Each list in your list is a reference to the same object. You modify one, you see the modification in all of them.

If you want different lists, you can do this way:

plot_data = [[] for _ in positions]

for example:

>>> pd = [[] for _ in range(3)]
>>> pd
[[], [], []]
>>> pd[0].append(1)
>>> pd
[[1], [], []]

How to see docker image contents

docker save nginx > nginx.tar
tar -xvf nginx.tar

Following files are present:

manifest.json – Describes filesystem layers and name of json file that has the Container properties.
.json – Container properties
– Each “layerid” directory contains json file describing layer property and filesystem associated with that layer. Docker stores Container images as layers to optimize storage space by reusing layers across images.

https://sreeninet.wordpress.com/2016/06/11/looking-inside-container-images/

you can use dive to view the image content interactively with TUI

https://github.com/wagoodman/dive

How can I use UIColorFromRGB in Swift?

This is worked for me in swift. Try this

bottomBorder.borderColor = UIColor (red: 255.0/255.0, green: 215.0/255.0, blue: 60/255.0, alpha: 1.0).CGColor

window.open with target "_blank" in Chrome

"_blank" is not guaranteed to be a new tab or window. It's implemented differently per-browser.

You can, however, put anything into target. I usually just say "_tab", and every browser I know of just opens it in a new tab.

Be aware that it means it's a named target, so if you try to open 2 URLs, they will use the same tab.

Reading an Excel file in PHP

I'm using below excel file url: https://github.com/inventorbala/Sample-Excel-files/blob/master/sample-excel-files.xlsx

Output:

How do I get an animated gif to work in WPF?

Check my code, I hope this helped you :)

         public async Task GIF_Animation_Pro(string FileName,int speed,bool _Repeat)
                    {
    int ab=0;
                        var gif = GifBitmapDecoder.Create(new Uri(FileName), BitmapCreateOptions.PreservePixelFormat, BitmapCacheOption.Default);
                        var getFrames = gif.Frames;
                        BitmapFrame[] frames = getFrames.ToArray();
                        await Task.Run(() =>
                        {


                            while (ab < getFrames.Count())
                            {
                                Thread.Sleep(speed);
try
{
                                Dispatcher.Invoke(() =>
                                {
                                    gifImage.Source = frames[ab];
                                });
                                if (ab == getFrames.Count - 1&&_Repeat)
                                {
                                    ab = 0;

                                }
                                ab++;
            }
 catch
{
}

                            }
                        });
                    }

     public async Task GIF_Animation_Pro(Stream stream, int speed,bool _Repeat)
            {
 int ab = 0;   
                var gif = GifBitmapDecoder.Create(stream , BitmapCreateOptions.PreservePixelFormat, BitmapCacheOption.Default);
                var getFrames = gif.Frames;
                BitmapFrame[] frames = getFrames.ToArray();
                await Task.Run(() =>
                {


                    while (ab < getFrames.Count())
                    {
                        Thread.Sleep(speed);
    try
    {


                     Dispatcher.Invoke(() =>
                        {
                            gifImage.Source = frames[ab];
                        });
                        if (ab == getFrames.Count - 1&&_Repeat)
                        {
                            ab = 0;

                        }
                        ab++;
    }
     catch{} 



                    }
                });
            }

How to comment out a block of code in Python

Another editor-based solution: text "rectangles" in Emacs.

Highlight the code you want to comment out, then C-x-r-t #

To un-comment the code: highlight, then C-x-r-k

I use this all-day, every day. (Assigned to hot-keys, of course.)

This and powerful regex search/replace is the reason I tolerate Emacs's other "eccentricities".

Why plt.imshow() doesn't display the image?

The solution was as simple as adding plt.show() at the end of the code snippet:

import numpy as np
np.random.seed(123)
from keras.models import Sequential
from keras.layers import Dense, Dropout, Activation, Flatten
from keras.layers import Convolution2D, MaxPooling2D
from keras.utils import np_utils
from keras.datasets import mnist
(X_train,y_train),(X_test,y_test) = mnist.load_data()
print X_train.shape
from matplotlib import pyplot as plt
plt.imshow(X_train[0])
plt.show()

AngularJs .$setPristine to reset form

Had a similar problem, where I had to set the form back to pristine, but also to untouched, since $invalid and $error were both used to show error messages. Only using setPristine() was not enough to clear the error messages.

I solved it by using setPristine() and setUntouched(). (See Angular's documentation: https://docs.angularjs.org/api/ng/type/ngModel.NgModelController)

So, in my controller, I used:

$scope.form.setPristine(); 
$scope.form.setUntouched();

These two functions reset the complete form to $pristine and back to $untouched, so that all error messages were cleared.

Daylight saving time and time zone best practices

For the web, the rules aren't that complicated...

Server-side, use UTC
Client-side, use Olson
- Reason: UTC-offsets are not daylight savings-safe (e.g. New York is EST (UTC - 5 Hours) part of the year, EDT (UTC - 4 Hours) rest of the year).
- For client-side time zone determination, you have two options:
  - 1) Have user set zone (Safer)
    - Resources: Web-ready Olson tz HTML Dropdown and JSON
  - 2) Auto-detect zone
    - Resource: jsTimezoneDetect

The rest is just UTC/local conversion using your server-side datetime libraries. Good to go...

ProcessStartInfo hanging on "WaitForExit"? Why?

Mark Byers' answer is excellent, but I would just add the following:

The OutputDataReceived and ErrorDataReceived delegates need to be removed before the outputWaitHandle and errorWaitHandle get disposed. If the process continues to output data after the timeout has been exceeded and then terminates, the outputWaitHandle and errorWaitHandle variables will be accessed after being disposed.

(FYI I had to add this caveat as an answer as I couldn't comment on his post.)

How to use ArrayList.addAll()?

Collections.addAll is what you want.

Collections.addAll(myArrayList, '+', '-', '*', '^');

Another option is to pass the list into the constructor using Arrays.asList like this:

List<Character> myArrayList = new ArrayList<Character>(Arrays.asList('+', '-', '*', '^'));

If, however, you are good with the arrayList being fixed-length, you can go with the creation as simple as list = Arrays.asList(...). Arrays.asList specification states that it returns a fixed-length list which acts as a bridge to the passed array, which could be not what you need.

How to read a CSV file from a URL with Python?

Using pandas it is very simple to read a csv file directly from a url

import pandas as pd
data = pd.read_csv('https://example.com/passkey=wedsmdjsjmdd')

This will read your data in tabular format, which will be very easy to process

How to force HTTPS using a web.config file

For those using ASP.NET MVC. You can use the RequireHttpsAttribute to force all responses to be HTTPS:

GlobalFilters.Filters.Add(new RequireHttpsAttribute());

Other things you may also want to do to help secure your site:

Force Anti-Forgery tokens to use SSL/TLS:
```
AntiForgeryConfig.RequireSsl = true;
```

Require Cookies to require HTTPS by default by changing the Web.config file:

<system.web>
    <httpCookies httpOnlyCookies="true" requireSSL="true" />
</system.web>

Use the NWebSec.Owin NuGet package and add the following line of code to enable Strict Transport Security (HSTS) across the site. Don't forget to add the Preload directive below and submit your site to the HSTS Preload site. More information here and here. Note that if you are not using OWIN, there is a Web.config method you can read up on on the NWebSec site.
```
// app is your OWIN IAppBuilder app in Startup.cs
app.UseHsts(options => options.MaxAge(days: 720).Preload());
```

Use the NWebSec.Owin NuGet package and add the following line of code to enable Public Key Pinning (HPKP) across the site. More information here and here.

// app is your OWIN IAppBuilder app in Startup.cs
app.UseHpkp(options => options
    .Sha256Pins(
        "Base64 encoded SHA-256 hash of your first certificate e.g. cUPcTAZWKaASuYWhhneDttWpY3oBAkE3h2+soZS7sWs=",
        "Base64 encoded SHA-256 hash of your second backup certificate e.g. M8HztCzM3elUxkcjR2S5P4hhyBNf6lHkmjAHKhpGPWE=")
    .MaxAge(days: 30));

Include the https scheme in any URL's used. Content Security Policy (CSP) HTTP header and Subresource Integrity (SRI) do not play nice when you imit the scheme in some browsers. It is better to be explicit about HTTPS. e.g.
```
<script src="https://ajax.aspnetcdn.com/ajax/bootstrap/3.3.4/bootstrap.min.js">
</script>
```
Use the ASP.NET MVC Boilerplate Visual Studio project template to generate a project with all of this and much more built in. You can also view the code on GitHub.

How to SSH into Docker?

Notice: this answer promotes a tool I've written.

The selected answer here suggests to install an SSH server into every image. Conceptually this is not the right approach (https://docs.docker.com/articles/dockerfile_best-practices/).

I've created a containerized SSH server that you can 'stick' to any running container. This way you can create compositions with every container. The only requirement is that the container has bash.

The following example would start an SSH server exposed on port 2222 of the local machine.

$ docker run -d -p 2222:22 \
  -v /var/run/docker.sock:/var/run/docker.sock \
  -e CONTAINER=my-container -e AUTH_MECHANISM=noAuth \
  jeroenpeeters/docker-ssh

$ ssh -p 2222 localhost

For more pointers and documentation see: https://github.com/jeroenpeeters/docker-ssh

Not only does this defeat the idea of one process per container, it is also a cumbersome approach when using images from the Docker Hub since they often don't (and shouldn't) contain an SSH server.

Multiple SQL joins

It will be something like this:

SELECT b.Title, b.Edition, b.Year, b.Pages, b.Rating, c.Category, p.Publisher, w.LastName
FROM
    Books b
    JOIN Categories_Book cb ON cb._ISBN = b._Books_ISBN
    JOIN Category c ON c._CategoryID = cb._Categories_Category_ID
    JOIN Publishers p ON p._PublisherID = b.PublisherID
    JOIN Writers_Books wb ON wb._Books_ISBN = b._ISBN
    JOIN Writer w ON w._WritersID = wb._Writers_WriterID

You use the join statement to indicate which fields from table A map to table B. I'm using aliases here thats why you see Books b the Books table will be referred to as b in the rest of the query. This makes for less typing.

FYI your naming convention is very strange, I would expect it to be more like this:

Book: ID, ISBN , BookTitle, Edition, Year, PublisherID, Pages, Rating
Category: ID, [Name]
BookCategory: ID, CategoryID, BookID
Publisher: ID, [Name]
Writer: ID, LastName
BookWriter: ID, WriterID, BookID

How to extract file name from path?

Here's a simple VBA solution I wrote that works with Windows, Unix, Mac, and URL paths.

sFileName = Mid(Mid(sPath, InStrRev(sPath, "/") + 1), InStrRev(sPath, "\") + 1)

sFolderName = Left(sPath, Len(sPath) - Len(sFileName))

You can test the output using this code:

'Visual Basic for Applications 
http = "https://www.server.com/docs/Letter.txt"
unix = "/home/user/docs/Letter.txt"
dos = "C:\user\docs\Letter.txt"
win = "\\Server01\user\docs\Letter.txt"
blank = ""

sPath = unix 
sFileName = Mid(Mid(sPath, InStrRev(sPath, "/") + 1), InStrRev(sPath, "\") + 1)
sFolderName = Left(sPath, Len(sPath) - Len(sFileName))

Debug.print "Folder: " & sFolderName & " File: " & sFileName

Also see: Wikipedia - Path (computing)

Display all dataframe columns in a Jupyter Python Notebook

I know this question is a little old but the following worked for me in a Jupyter Notebook running pandas 0.22.0 and Python 3:

import pandas as pd
pd.set_option('display.max_columns', <number of columns>)

You can do the same for the rows too:

pd.set_option('display.max_rows', <number of rows>)

This saves importing IPython, and there are more options in the pandas.set_option documentation: https://pandas.pydata.org/pandas-docs/stable/reference/api/pandas.set_option.html

How to generate unique ID with node.js

node-uuid is deprecated so please use uuid

npm install uuid --save
// Generate a v1 UUID (time-based) 
const uuidV1 = require('uuid/v1');
uuidV1(); // -> '6c84fb90-12c4-11e1-840d-7b25c5ee775a' 

// Generate a v4 UUID (random) 
const uuidV4 = require('uuid/v4');
uuidV4(); // -> '110ec58a-a0f2-4ac4-8393-c866d813b8d1'

Npm link

How to set the java.library.path from Eclipse

For a given application launch, you can do it as jim says.

If you want to set it for the entire workspace, you can also set it under

Window->
  Preferences->
    Java->
      Installed JREs

Each JRE has a "Default VM arguments" (which I believe are completely ignored if any VM args are set for a run configuration.)

You could even set up different JRE/JDKs with different parameters and have some projects use one, other projects use another.

MYSQL Sum Query with IF Condition

How about this?

SUM(IF(PaymentType = "credit card", totalamount, 0)) AS CreditCardTotal

Alert handling in Selenium WebDriver (selenium 2) with Java

Alert alert = driver.switchTo().alert();

alert.accept();

You can also decline the alert box:


Alert alert = driver.switchTo().alert();

alert().dismiss();

Android: how to refresh ListView contents?

I'm doing the same thing using invalidateViews() and that works for me. If you want it to invalidate immediately you could try calling postInvalidate after calling invalidateViews.

Finding three elements in an array whose sum is closest to a given number

Here is the program in java which is O(N^2)

import java.util.Stack;


public class GetTripletPair {

    /** Set a value for target sum */
    public static final int TARGET_SUM = 32;

    private Stack<Integer> stack = new Stack<Integer>();

    /** Store the sum of current elements stored in stack */
    private int sumInStack = 0;
    private int count =0 ;


    public void populateSubset(int[] data, int fromIndex, int endIndex) {

        /*
        * Check if sum of elements stored in Stack is equal to the expected
        * target sum.
        * 
        * If so, call print method to print the candidate satisfied result.
        */
        if (sumInStack == TARGET_SUM) {
            print(stack);
        }

        for (int currentIndex = fromIndex; currentIndex < endIndex; currentIndex++) {

            if (sumInStack + data[currentIndex] <= TARGET_SUM) {
                ++count;
                stack.push(data[currentIndex]);
                sumInStack += data[currentIndex];

                /*
                * Make the currentIndex +1, and then use recursion to proceed
                * further.
                */
                populateSubset(data, currentIndex + 1, endIndex);
                --count;
                sumInStack -= (Integer) stack.pop();
            }else{
            return;
        }
        }
    }

    /**
    * Print satisfied result. i.e. 15 = 4+6+5
    */

    private void print(Stack<Integer> stack) {
        StringBuilder sb = new StringBuilder();
        sb.append(TARGET_SUM).append(" = ");
        for (Integer i : stack) {
            sb.append(i).append("+");
        }
        System.out.println(sb.deleteCharAt(sb.length() - 1).toString());
    }

    private static final int[] DATA = {4,13,14,15,17};

    public static void main(String[] args) {
        GetAllSubsetByStack get = new GetAllSubsetByStack();
        get.populateSubset(DATA, 0, DATA.length);
    }
}

SQLite in Android How to update a specific row

At first create a ContentValues object :

ContentValues cv = new ContentValues();
cv.put("Field1","Bob");
cv.put("Field2","19");

Then use the update method. Note, the third argument is the where clause. The "?" is a placeholder. It will be replaced with the fourth argument (id)

myDB.update(MY_TABLE_NAME, cv, "_id = ?", new String[]{id});

This is the cleanest solution to update a specific row.

Change color inside strings.xml

I would use a SpannableString to change the color.

int colorBlue = getResources().getColor(R.color.blue);
    String text = getString(R.string.text);
    SpannableString spannable = new SpannableString(text);
    // here we set the color
    spannable.setSpan(new ForegroundColorSpan(colorBlue), 0, text.length(), 0);

OR you may try this

Passing Multiple route params in Angular2

Two Methods for Passing Multiple route params in Angular

Method-1

In app.module.ts

Set path as component2.

imports: [
 RouterModule.forRoot(
 [ {path: 'component2/:id1/:id2', component: MyComp2}])
]

Call router to naviagte to MyComp2 with multiple params id1 and id2.

export class MyComp1 {
onClick(){
    this._router.navigate( ['component2', "id1","id2"]);
 }
}

Method-2

In app.module.ts

Set path as component2.

imports: [
 RouterModule.forRoot(
 [ {path: 'component2', component: MyComp2}])
]

Call router to naviagte to MyComp2 with multiple params id1 and id2.

export class MyComp1 {
onClick(){
    this._router.navigate( ['component2', {id1: "id1 Value", id2: 
    "id2  Value"}]);
 }
}

How do you install GLUT and OpenGL in Visual Studio 2012?

Download the GLUT library. At first step Copy the glut32.dll and paste it in C:\Windows\System32 folder.Second step copy glut.h file and paste it in C:\Program Files\Microsoft Visual Studio\VC\include folder and third step copy glut32.lib and paste it in c:\Program Files\Microsoft Visual Studio\VC\lib folder. Now you can create visual c++ console application project and include glut.h header file then you can write code for GLUT project. If you are using 64 bit windows machine then path and glut library may be different but process is similar.

Vertical divider CSS

.headerDivider {
     border-left:1px solid #38546d; 
     border-right:1px solid #16222c; 
     height:80px;
     position:absolute;
     right:249px;
     top:10px; 
}

<div class="headerDivider"></div>

How to delete a folder with files using Java

directry cannot simply delete if it has the files so you may need to delete the files inside first and then directory

public class DeleteFileFolder {

public DeleteFileFolder(String path) {

    File file = new File(path);
    if(file.exists())
    {
        do{
            delete(file);
        }while(file.exists());
    }else
    {
        System.out.println("File or Folder not found : "+path);
    }

}
private void delete(File file)
{
    if(file.isDirectory())
    {
        String fileList[] = file.list();
        if(fileList.length == 0)
        {
            System.out.println("Deleting Directory : "+file.getPath());
            file.delete();
        }else
        {
            int size = fileList.length;
            for(int i = 0 ; i < size ; i++)
            {
                String fileName = fileList[i];
                System.out.println("File path : "+file.getPath()+" and name :"+fileName);
                String fullPath = file.getPath()+"/"+fileName;
                File fileOrFolder = new File(fullPath);
                System.out.println("Full Path :"+fileOrFolder.getPath());
                delete(fileOrFolder);
            }
        }
    }else
    {
        System.out.println("Deleting file : "+file.getPath());
        file.delete();
    }
}

SQL How to Select the most recent date item

With SQL Server try:

SELECT TOP 1 * FROM dbo.youTable WHERE user_id = 'userid' ORDER BY date_added desc

Python reshape list to ndim array

You can think of reshaping that the new shape is filled row by row (last dimension varies fastest) from the flattened original list/array.

An easy solution is to shape the list into a (100, 28) array and then transpose it:

x = np.reshape(list_data, (100, 28)).T

Update regarding the updated example:

np.reshape([0, 0, 1, 1, 2, 2, 3, 3], (4, 2)).T
# array([[0, 1, 2, 3],
#        [0, 1, 2, 3]])

np.reshape([0, 0, 1, 1, 2, 2, 3, 3], (2, 4))
# array([[0, 0, 1, 1],
#        [2, 2, 3, 3]])

Way to get number of digits in an int?

Another string approach. Short and sweet - for any integer n.

int length = ("" + n).length();

JavaScript: filter() for Objects

First of all, it's considered bad practice to extend Object.prototype. Instead, provide your feature as utility function on Object, just like there already are Object.keys, Object.assign, Object.is, ...etc.

I provide here several solutions:

Using reduce and Object.keys
As (1), in combination with Object.assign
Using map and spread syntax instead of reduce
Using Object.entries and Object.fromEntries

1. Using `reduce` and `Object.keys`

With reduce and Object.keys to implement the desired filter (using ES6 arrow syntax):

_x000D_

Object.filter = (obj, predicate) => _x000D_
    Object.keys(obj)_x000D_
          .filter( key => predicate(obj[key]) )_x000D_
          .reduce( (res, key) => (res[key] = obj[key], res), {} );_x000D_
_x000D_
// Example use:_x000D_
var scores = {_x000D_
    John: 2, Sarah: 3, Janet: 1_x000D_
};_x000D_
var filtered = Object.filter(scores, score => score > 1); _x000D_
console.log(filtered);

_x000D_

Note that in the above code predicate must be an inclusion condition (contrary to the exclusion condition the OP used), so that it is in line with how Array.prototype.filter works.

2. As (1), in combination with `Object.assign`

In the above solution the comma operator is used in the reduce part to return the mutated res object. This could of course be written as two statements instead of one expression, but the latter is more concise. To do it without the comma operator, you could use Object.assign instead, which does return the mutated object:

_x000D_

Object.filter = (obj, predicate) => _x000D_
    Object.keys(obj)_x000D_
          .filter( key => predicate(obj[key]) )_x000D_
          .reduce( (res, key) => Object.assign(res, { [key]: obj[key] }), {} );_x000D_
_x000D_
// Example use:_x000D_
var scores = {_x000D_
    John: 2, Sarah: 3, Janet: 1_x000D_
};_x000D_
var filtered = Object.filter(scores, score => score > 1); _x000D_
console.log(filtered);

_x000D_

3. Using `map` and spread syntax instead of `reduce`

Here we move the Object.assign call out of the loop, so it is only made once, and pass it the individual keys as separate arguments (using the spread syntax):

_x000D_

Object.filter = (obj, predicate) => _x000D_
    Object.assign(...Object.keys(obj)_x000D_
                    .filter( key => predicate(obj[key]) )_x000D_
                    .map( key => ({ [key]: obj[key] }) ) );_x000D_
_x000D_
// Example use:_x000D_
var scores = {_x000D_
    John: 2, Sarah: 3, Janet: 1_x000D_
};_x000D_
var filtered = Object.filter(scores, score => score > 1); _x000D_
console.log(filtered);

_x000D_

4. Using `Object.entries` and `Object.fromEntries`

As the solution translates the object to an intermediate array and then converts that back to a plain object, it would be useful to make use of Object.entries (ES2017) and the opposite (i.e. create an object from an array of key/value pairs) with Object.fromEntries (ES2019).

It leads to this "one-liner" method on Object:

_x000D_

Object.filter = (obj, predicate) => _x000D_
                  Object.fromEntries(Object.entries(obj).filter(predicate));_x000D_
_x000D_
// Example use:_x000D_
var scores = {_x000D_
    John: 2, Sarah: 3, Janet: 1_x000D_
};_x000D_
_x000D_
var filtered = Object.filter(scores, ([name, score]) => score > 1); _x000D_
console.log(filtered);

_x000D_

The predicate function gets a key/value pair as argument here, which is a bit different, but allows for more possibilities in the predicate function's logic.

Converting a list to a set changes element order

You can remove the duplicated values and keep the list order of insertion with one line of code, Python 3.8.2

mylist = ['b', 'b', 'a', 'd', 'd', 'c']


results = list({value:"" for value in mylist})

print(results)

>>> ['b', 'a', 'd', 'c']

results = list(dict.fromkeys(mylist))

print(results)

>>> ['b', 'a', 'd', 'c']

Is it possible to run a .NET 4.5 app on XP?

The Mono project dropped Windows XP support and "forgot" to mention it. Although they still claim Windows XP SP2 is the minimum supported version, it is actually Windows Vista.

The last version of Mono to support Windows XP was 3.2.3.

convert a JavaScript string variable to decimal/money

You can also use the Number constructor/function (no need for a radix and usable for both integers and floats):

Number('09'); /=> 9
Number('09.0987'); /=> 9.0987

Alternatively like Andy E said in the comments you can use + for conversion

+'09'; /=> 9
+'09.0987'; /=> 9.0987

How can I get screen resolution in java?

This call will give you the information you want.

Dimension screenSize = Toolkit.getDefaultToolkit().getScreenSize();

How to trigger event when a variable's value is changed?

just use a property

int  _theVariable;
public int TheVariable{
  get{return _theVariable;}
  set{
    _theVariable = value; 
    if ( _theVariable == 1){
      //Do stuff here.
    }
  }
}

How do I create a crontab through a script

It is an approach to incrementally add the cron job:

  ssh USER_NAME@$PRODUCT_IP nohup "echo '*/2 * * * * ping -c2 PRODUCT_NAME.com >> /var/www/html/test.html' | crontab -u USER_NAME -"

Iterating on a file doesn't work the second time

Yes, that is normal behavior. You basically read to the end of the file the first time (you can sort of picture it as reading a tape), so you can't read any more from it unless you reset it, by either using f.seek(0) to reposition to the start of the file, or to close it and then open it again which will start from the beginning of the file.

If you prefer you can use the with syntax instead which will automatically close the file for you.

e.g.,

with open('baby1990.html', 'rU') as f:
  for line in f:
     print line

once this block is finished executing, the file is automatically closed for you, so you could execute this block repeatedly without explicitly closing the file yourself and read the file this way over again.

How to make an ImageView with rounded corners?

You can try this library - RoundedImageView

It is:

A fast ImageView that supports rounded corners, ovals, and circles. A full superset of CircleImageView.

I've used it in my project, and it is very easy.

How to convert array values to lowercase in PHP?

use array_map():

$yourArray = array_map('strtolower', $yourArray);

In case you need to lowercase nested array (by Yahya Uddin):

$yourArray = array_map('nestedLowercase', $yourArray);

function nestedLowercase($value) {
    if (is_array($value)) {
        return array_map('nestedLowercase', $value);
    }
    return strtolower($value);
}

How to get ID of clicked element with jQuery

You just need to remove the hash from the beginning:

$('a.pagerlink').click(function() { 
    var id = $(this).attr('id').substring(1);
    $container.cycle(id); 
    return false; 
});

How to compare two java objects

1) == evaluates reference equality in this case
2) im not too sure about the equals, but why not simply overriding the compare method and plant it inside MyClass?

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

Try This:

sqlplus -s ${ORA_CONN_STR} <<EOF >/dev/null

File upload from <input type="file">

Try this small lib, works with Angular 5.0.0

https://www.npmjs.com/package/ng2-file-upload

Quickstart example with ng2-file-upload 1.3.0:

User clicks custom button, which triggers upload dialog from hidden input type="file" , uploading started automatically after selecting single file.

app.module.ts:

import {FileUploadModule} from "ng2-file-upload";

your.component.html:

...
  <button mat-button onclick="document.getElementById('myFileInputField').click()" >
    Select and upload file
  </button>
  <input type="file" id="myFileInputField" ng2FileSelect [uploader]="uploader" style="display:none">
...

your.component.ts:

import {FileUploader} from 'ng2-file-upload';
...    
uploader: FileUploader;
...
constructor() {
   this.uploader = new FileUploader({url: "/your-api/some-endpoint"});
   this.uploader.onErrorItem = item => {
       console.error("Failed to upload");
       this.clearUploadField();
   };
   this.uploader.onCompleteItem = (item, response) => {
       console.info("Successfully uploaded");
       this.clearUploadField();

       // (Optional) Parsing of response
       let responseObject = JSON.parse(response) as MyCustomClass;

   };

   // Asks uploader to start upload file automatically after selecting file
  this.uploader.onAfterAddingFile = fileItem => this.uploader.uploadAll();
}

private clearUploadField(): void {
    (<HTMLInputElement>window.document.getElementById('myFileInputField'))
    .value = "";
}

Alternative lib, works in Angular 4.2.4, but requires some workarounds to adopt to Angular 5.0.0

https://www.npmjs.com/package/angular2-http-file-upload

Python "SyntaxError: Non-ASCII character '\xe2' in file"

If you are just trying to use UTF-8 characters or don't care if they are in your code, add this line to the top of your .py file

# -*- coding: utf-8 -*-

Get selected item value from Bootstrap DropDown with specific ID

You might want to modify your jQuery code a bit to '#demolist li a' so it specifically selects the text that is in the link rather than the text that is in the li element. That would allow you to have a sub-menu without causing issues. Also since your are specifically selecting the a tag you can access it with $(this).text();.

$('#datebox li a').on('click', function(){
    //$('#datebox').val($(this).text());
    alert($(this).text());
});

Splitting string into multiple rows in Oracle

regular expressions is a wonderful thing :)

with temp as  (
       select 108 Name, 'test' Project, 'Err1, Err2, Err3' Error  from dual
       union all
       select 109, 'test2', 'Err1' from dual
     )

SELECT distinct Name, Project, trim(regexp_substr(str, '[^,]+', 1, level)) str
  FROM (SELECT Name, Project, Error str FROM temp) t
CONNECT BY instr(str, ',', 1, level - 1) > 0
order by Name

Why is String immutable in Java?

If HELLO is your String then you can't change HELLO to HILLO. This property is called immutability property.

You can have multiple pointer String variable to point HELLO String.

But if HELLO is char Array then you can change HELLO to HILLO. Eg,

char[] charArr = 'HELLO';
char[1] = 'I'; //you can do this

Answer:

Programming languages have immutable data variables so that it can be used as keys in key, value pair. String variables are used as keys/indices, so they are immutable.

Docker official registry (Docker Hub) URL

For those trying to create a Google Cloud instance using the "Deploy a container image to this VM instance." option then the correct url format would be

docker.io/<dockerimagename>:version

The suggestion above of registry.hub.docker.com/library/<dockerimagename> did not work for me.

I finally found the solution here (in my case, i was trying to run docker.io/tensorflow/serving:latest)

Creating java date object from year,month,day

Months are zero-based in Calendar. So 12 is interpreted as december + 1 month. Use

c.set(year, month - 1, day, 0, 0);

How to prevent scientific notation in R?

To set the use of scientific notation in your entire R session, you can use the scipen option. From the documentation (?options):

‘scipen’: integer.  A penalty to be applied when deciding to print
          numeric values in fixed or exponential notation.  Positive
          values bias towards fixed and negative towards scientific
          notation: fixed notation will be preferred unless it is more
          than ‘scipen’ digits wider.

So in essence this value determines how likely it is that scientific notation will be triggered. So to prevent scientific notation, simply use a large positive value like 999:

options(scipen=999)

How to undo 'git reset'?

1.Use git reflog to get all references update.

2.git reset <id_of_commit_to_which_you_want_restore>

Hiding table data using <div style="display:none">

Just apply the style attribute to the tr tag. In the case of multiple tr tags, you will have to apply the style to each element, or wrap them in a tbody tag:

<table>
  <tr><th>Test Table</th><tr>
  <tbody style="display:none">
    <tr><td>123456789</td><tr>
    <tr><td>123456789</td><tr>
    <tr><td>123456789</td><tr>
  </tbody>
</table>

Read file content from S3 bucket with boto3

You might also consider the smart_open module, which supports iterators:

from smart_open import smart_open

# stream lines from an S3 object
for line in smart_open('s3://mybucket/mykey.txt', 'rb'):
    print(line.decode('utf8'))

and context managers:

with smart_open('s3://mybucket/mykey.txt', 'rb') as s3_source:
    for line in s3_source:
         print(line.decode('utf8'))

    s3_source.seek(0)  # seek to the beginning
    b1000 = s3_source.read(1000)  # read 1000 bytes

Find smart_open at https://pypi.org/project/smart_open/

Changing Underline color

In practice, it is possible, if you use span element instead of font:

<style>
u { color: black; }
.red { color: red }
</style>
<u><span class='red'><br>$username</span></u>

See jsfiddle. Appears to work on Chrome, Safari, Firefox, IE, Opera (tested on Win 7 with newest versions).

The code in the question should work, too, but it does not work for some reason on WebKit browsers (Chrome, Safari).

By the CSS spec: “The color(s) required for the text decoration must be derived from the 'color' property value of the element on which 'text-decoration' is set. The color of decorations must remain the same even if descendant elements have different 'color' values.”

What Ruby IDE do you prefer?

E Text Editor is great (TextMate compatible sort-of-clone for Windows).

Adjust plot title (main) position

To summarize and explain visually how it works. Code construction is as follows:

par(mar = c(3,2,2,1))
barplot(...all parameters...)
title("Title text", adj = 0.5, line = 0)

explanation:

par(mar = c(low, left, top, right)) - margins of the graph area.

title("text" - title text
      adj  = from left (0) to right (1) with anything in between: 0.1, 0.2, etc...
      line = positive values move title text up, negative - down)

Styling a disabled input with css only

A space in a CSS selector selects child elements.

.btn input

This is basically what you wrote and it would select <input> elements within any element that has the btn class.

I think you're looking for

input[disabled].btn:hover, input[disabled].btn:active, input[disabled].btn:focus

This would select <input> elements with the disabled attribute and the btn class in the three different states of hover, active and focus.

Razor View throwing "The name 'model' does not exist in the current context"

I had the same problem when deploying to an Azure App Service

In my case it was because ~/Views/Web.config wasn't included in the project.

It worked in IIS Express but when I deployed to azure, I got the same error. By not being included in the .csproj file, it wasn't deployed.

The solution was to ensure ~/Views/Web.config is included in the project.

If you go to solution explorer and click the "Show all files" icon, then open up Views you might see an unincluded Web.config file under there.

Add it in, re-publish, and bob's your uncle.

CSS Flex Box Layout: full-width row and columns

You've almost done it. However setting flex: 0 0 <basis> declaration to the columns would prevent them from growing/shrinking; And the <basis> parameter would define the width of columns.

In addition, you could use CSS3 calc() expression to specify the height of columns with the respect to the height of the header.

#productShowcaseTitle {
  flex: 0 0 100%; /* Let it fill the entire space horizontally */
  height: 100px;
}

#productShowcaseDetail,
#productShowcaseThumbnailContainer {
  height: calc(100% - 100px); /* excluding the height of the header */
}

_x000D_

#productShowcaseContainer {_x000D_
  display: flex;_x000D_
  flex-flow: row wrap;_x000D_
_x000D_
  height: 600px;_x000D_
  width: 580px;_x000D_
}_x000D_
_x000D_
#productShowcaseTitle {_x000D_
  flex: 0 0 100%; /* Let it fill the entire space horizontally */_x000D_
  height: 100px;_x000D_
  background-color: silver;_x000D_
}_x000D_
_x000D_
#productShowcaseDetail {_x000D_
  flex: 0 0 66%; /* ~ 2 * 33.33% */_x000D_
  height: calc(100% - 100px); /* excluding the height of the header */_x000D_
  background-color: lightgray;_x000D_
}_x000D_
_x000D_
#productShowcaseThumbnailContainer {_x000D_
  flex: 0 0 34%;  /* ~ 33.33% */_x000D_
  height: calc(100% - 100px); /* excluding the height of the header */_x000D_
  background-color: black;_x000D_
}

_x000D_

<div id="productShowcaseContainer">_x000D_
  <div id="productShowcaseTitle"></div>_x000D_
  <div id="productShowcaseDetail"></div>_x000D_
  <div id="productShowcaseThumbnailContainer"></div>_x000D_
</div>

_x000D_

(Vendor prefixes omitted due to brevity)

Alternatively, if you could change your markup e.g. wrapping the columns by an additional <div> element, it would be achieved without using calc() as follows:

<div class="contentContainer"> <!-- Added wrapper -->
    <div id="productShowcaseDetail"></div>
    <div id="productShowcaseThumbnailContainer"></div>
</div>

#productShowcaseContainer {
  display: flex;
  flex-direction: column;
  height: 600px; width: 580px;
}

.contentContainer { display: flex; flex: 1; }
#productShowcaseDetail { flex: 3; }
#productShowcaseThumbnailContainer { flex: 2; }

_x000D_

#productShowcaseContainer {_x000D_
  display: flex;_x000D_
  flex-direction: column;_x000D_
_x000D_
  height: 600px;_x000D_
  width: 580px;_x000D_
}_x000D_
_x000D_
.contentContainer {_x000D_
  display: flex;_x000D_
  flex: 1;_x000D_
}_x000D_
_x000D_
#productShowcaseTitle {_x000D_
  height: 100px;_x000D_
  background-color: silver;_x000D_
}_x000D_
_x000D_
#productShowcaseDetail {_x000D_
  flex: 3;_x000D_
  background-color: lightgray;_x000D_
}_x000D_
_x000D_
#productShowcaseThumbnailContainer {_x000D_
  flex: 2;_x000D_
  background-color: black;_x000D_
}

_x000D_

<div id="productShowcaseContainer">_x000D_
  <div id="productShowcaseTitle"></div>_x000D_
_x000D_
  <div class="contentContainer"> <!-- Added wrapper -->_x000D_
    <div id="productShowcaseDetail"></div>_x000D_
    <div id="productShowcaseThumbnailContainer"></div>_x000D_
  </div>_x000D_
</div>

_x000D_

(Vendor prefixes omitted due to brevity)

Android Volley - BasicNetwork.performRequest: Unexpected response code 400

Just to update all, after some deliberations, I have decided to use Async Http Client instead to solve my earlier problem. The library allows a cleaner approach (to me) to manipulate HTTP responses especially in cases where JSON objects are returned in all scenarios/HTTP statuses.

protected void getLogin() {

    EditText username = (EditText) findViewById(R.id.username); 
    EditText password = (EditText) findViewById(R.id.password); 

    RequestParams params = new RequestParams();
    params.put("username", username.getText().toString());
    params.put("password", password.getText().toString());

    RestClient.post(getHost() + "api/v1/auth/login", params,
            new JsonHttpResponseHandler() {

        @Override
        public void onSuccess(int statusCode, Header[] headers,
                JSONObject response) {

            try {

                //process JSONObject obj 
                Log.w("myapp","success status code..." + statusCode);

            } catch (JSONException e) {
                // TODO Auto-generated catch block
                e.printStackTrace();
            }
        }

        @Override
        public void onFailure(int statusCode, Header[] headers,
                Throwable throwable, JSONObject errorResponse) {
            Log.w("myapp", "failure status code..." + statusCode);


            try {
                //process JSONObject obj
                Log.w("myapp", "error ..."  + errorResponse.getString("message").toString());
            } catch (JSONException e) {
                // TODO Auto-generated catch block
                e.printStackTrace();
            }
        }
    });
}

How to add hours to current time in python

from datetime import datetime, timedelta

nine_hours_from_now = datetime.now() + timedelta(hours=9)
#datetime.datetime(2012, 12, 3, 23, 24, 31, 774118)

And then use string formatting to get the relevant pieces:

>>> '{:%H:%M:%S}'.format(nine_hours_from_now)
'23:24:31'

If you're only formatting the datetime then you can use:

>>> format(nine_hours_from_now, '%H:%M:%S')
'23:24:31'

Or, as @eumiro has pointed out in comments - strftime

What is the best way to get the first letter from a string in Java, returned as a string of length 1?

Performance wise substring(0, 1) is better as found by following:

    String example = "something";
    String firstLetter  = "";

    long l=System.nanoTime();
    firstLetter = String.valueOf(example.charAt(0));
    System.out.println("String.valueOf: "+ (System.nanoTime()-l));

    l=System.nanoTime();
    firstLetter = Character.toString(example.charAt(0));
    System.out.println("Character.toString: "+ (System.nanoTime()-l));

    l=System.nanoTime();
    firstLetter = example.substring(0, 1);
    System.out.println("substring: "+ (System.nanoTime()-l));

Output:

String.valueOf: 38553
Character.toString: 30451
substring: 8660

Calling a Variable from another Class

class Program
{
    Variable va = new Variable();
    static void Main(string[] args)
    {
        va.name = "Stackoverflow";
    }
}

How to delete all files older than 3 days when "Argument list too long"?

Another solution for the original question, esp. useful if you want to remove only SOME of the older files in a folder, would be smth like this:

find . -name "*.sess" -mtime +100

and so on.. Quotes block shell wildcards, thus allowing you to "find" millions of files :)

Titlecase all entries into a form_for text field

You don't want to take care of normalizing your data in a view - what if the user changes the data that gets submitted? Instead you could take care of it in the model using the before_save (or the before_validation) callback. Here's an example of the relevant code for a model like yours:

class Place < ActiveRecord::Base   before_save do |place|     place.city = place.city.downcase.titleize     place.country = place.country.downcase.titleize   end end

You can also check out the Ruby on Rails guide for more info.

To answer you question more directly, something like this would work:

<%= f.text_field :city, :value => (f.object.city ? f.object.city.titlecase : '') %>

This just means if f.object.city exists, display the titlecase version of it, and if it doesn't display a blank string.

How do you run a single query through mysql from the command line?

From the mysql man page:

   You can execute SQL statements in a script file (batch file) like this:

       shell> mysql db_name < script.sql > output.tab

Put the query in script.sql and run it.

Error while installing json gem 'mkmf.rb can't find header files for ruby'

BEFORE you follow the tip from Joki's answer (below) and IF :

you have MacOS 10.14.6
at /Library/Developer/CommandLineTools/SDKs/ you have folders MacOSX.sdk(symbolic), MacOSX10.14.sdk, MacOSX10.15.sdk
Move MacOSX10.15.sdk to anywhere (admin privileges needs)
Delete symbolic link (admin privileges needs)
At /Library/Developer/CommandLineTools/SDKs/ create another symbolic link now to MacOSX10.14.sdk folder using (admin privileges needs)

sudo ln -s /Library/Developer/CommandLineTools/SDKs/MacOSX10.14.sdk MacOSX.sdk
Now you can follow Joki's answer

WARNING! If you move MacOSX10.15.sdk folder to /Library/Developer/CommandLineTools/SDKs/ again, the command

ruby -rrbconfig -e 'puts RbConfig::CONFIG["rubyhdrdir"]'

will show MacOSX10.15.sdk folder like default again, nowadays I dunno how to fix it! My suggestion, compress the folder and put the original folder until fix will be available.

How to multiply duration by integer?

My turn:

https://play.golang.org/p/RifHKsX7Puh

package main

import (
    "fmt"
    "time"
)

func main() {
    var n int = 77
    v := time.Duration( 1.15 * float64(n) ) * time.Second

    fmt.Printf("%v %T", v, v)
}

It helps to remember the simple fact, that underlyingly the time.Duration is a mere int64, which holds nanoseconds value.

This way, conversion to/from time.Duration becomes a formality. Just remember:

int64
always nanosecs

Simplest way to append data to a SQL Column

how to specify new environment location for conda create

You can create it like this

conda create --prefix C:/tensorflow2 python=3.7

and you don't have to move to that folder to activate it.

# To activate this environment, use:
# > activate C:\tensorflow2

As you see I do it like this.

D:\Development_Avector\PycharmProjects\TensorFlow>activate C:\tensorflow2

(C:\tensorflow2) D:\Development_Avector\PycharmProjects\TensorFlow>

(C:\tensorflow2) D:\Development_Avector\PycharmProjects\TensorFlow>conda --version
conda 4.5.13

Retrieving subfolders names in S3 bucket from boto3

The following works for me... S3 objects:

s3://bucket/
    form1/
       section11/
          file111
          file112
       section12/
          file121
    form2/
       section21/
          file211
          file112
       section22/
          file221
          file222
          ...
      ...
   ...

Using:

from boto3.session import Session
s3client = session.client('s3')
resp = s3client.list_objects(Bucket=bucket, Prefix='', Delimiter="/")
forms = [x['Prefix'] for x in resp['CommonPrefixes']]

we get:

form1/
form2/
...

With:

resp = s3client.list_objects(Bucket=bucket, Prefix='form1/', Delimiter="/")
sections = [x['Prefix'] for x in resp['CommonPrefixes']]

we get:

form1/section11/
form1/section12/

How to see remote tags?

Even without cloning or fetching, you can check the list of tags on the upstream repo with git ls-remote:

git ls-remote --tags /url/to/upstream/repo

(as illustrated in "When listing git-ls-remote why there's “^{}” after the tag name?")

xbmono illustrates in the comments that quotes are needed:

git ls-remote --tags /some/url/to/repo "refs/tags/MyTag^{}"

Note that you can always push your commits and tags in one command with (git 1.8.3+, April 2013):

git push --follow-tags

See Push git commits & tags simultaneously.

Regarding Atlassian SourceTree specifically:

Note that, from this thread, SourceTree ONLY shows local tags.

There is an RFE (Request for Enhancement) logged in SRCTREEWIN-4015 since Dec. 2015.

A simple workaround:

see a list of only unpushed tags?

git push --tags

or check the "Push all tags" box on the "Push" dialog box, all tags will be pushed to your remote.

That way, you will be "sure that they are present in remote so that other developers can pull them".

Should 'using' directives be inside or outside the namespace?

This thread already has some great answers, but I feel I can bring a little more detail with this additional answer.

First, remember that a namespace declaration with periods, like:

namespace MyCorp.TheProduct.SomeModule.Utilities
{
    ...
}

is entirely equivalent to:

namespace MyCorp
{
    namespace TheProduct
    {
        namespace SomeModule
        {
            namespace Utilities
            {
                ...
            }
        }
    }
}

If you wanted to, you could put using directives on all of these levels. (Of course, we want to have usings in only one place, but it would be legal according to the language.)

The rule for resolving which type is implied, can be loosely stated like this: First search the inner-most "scope" for a match, if nothing is found there go out one level to the next scope and search there, and so on, until a match is found. If at some level more than one match is found, if one of the types are from the current assembly, pick that one and issue a compiler warning. Otherwise, give up (compile-time error).

Now, let's be explicit about what this means in a concrete example with the two major conventions.

(1) With usings outside:

using System;
using System.Collections.Generic;
using System.Linq;
//using MyCorp.TheProduct;  <-- uncommenting this would change nothing
using MyCorp.TheProduct.OtherModule;
using MyCorp.TheProduct.OtherModule.Integration;
using ThirdParty;

namespace MyCorp.TheProduct.SomeModule.Utilities
{
    class C
    {
        Ambiguous a;
    }
}

In the above case, to find out what type Ambiguous is, the search goes in this order:

Nested types inside C (including inherited nested types)
Types in the current namespace MyCorp.TheProduct.SomeModule.Utilities
Types in namespace MyCorp.TheProduct.SomeModule
Types in MyCorp.TheProduct
Types in MyCorp
Types in the null namespace (the global namespace)
Types in System, System.Collections.Generic, System.Linq, MyCorp.TheProduct.OtherModule, MyCorp.TheProduct.OtherModule.Integration, and ThirdParty

The other convention:

(2) With usings inside:

namespace MyCorp.TheProduct.SomeModule.Utilities
{
    using System;
    using System.Collections.Generic;
    using System.Linq;
    using MyCorp.TheProduct;                           // MyCorp can be left out; this using is NOT redundant
    using MyCorp.TheProduct.OtherModule;               // MyCorp.TheProduct can be left out
    using MyCorp.TheProduct.OtherModule.Integration;   // MyCorp.TheProduct can be left out
    using ThirdParty;

    class C
    {
        Ambiguous a;
    }
}

Now, search for the type Ambiguous goes in this order:

Nested types inside C (including inherited nested types)
Types in the current namespace MyCorp.TheProduct.SomeModule.Utilities
Types in System, System.Collections.Generic, System.Linq, MyCorp.TheProduct, MyCorp.TheProduct.OtherModule, MyCorp.TheProduct.OtherModule.Integration, and ThirdParty
Types in namespace MyCorp.TheProduct.SomeModule
Types in MyCorp
Types in the null namespace (the global namespace)

(Note that MyCorp.TheProduct was a part of "3." and was therefore not needed between "4." and "5.".)

Concluding remarks

No matter if you put the usings inside or outside the namespace declaration, there's always the possibility that someone later adds a new type with identical name to one of the namespaces which have higher priority.

Also, if a nested namespace has the same name as a type, it can cause problems.

It is always dangerous to move the usings from one location to another because the search hierarchy changes, and another type may be found. Therefore, choose one convention and stick to it, so that you won't have to ever move usings.

Visual Studio's templates, by default, put the usings outside of the namespace (for example if you make VS generate a new class in a new file).

One (tiny) advantage of having usings outside is that you can then utilize the using directives for a global attribute, for example [assembly: ComVisible(false)] instead of [assembly: System.Runtime.InteropServices.ComVisible(false)].

How do I view 'git diff' output with my preferred diff tool/ viewer?

Solution for Windows/msys git

After reading the answers, I discovered a simpler way that involves changing only one file.

Create a batch file to invoke your diff program, with argument 2 and 5. This file must be somewhere in your path. (If you don't know where that is, put it in c:\windows). Call it, for example, "gitdiff.bat". Mine is:
```
@echo off
REM This is gitdiff.bat
"C:\Program Files\WinMerge\WinMergeU.exe" %2 %5
```
Set the environment variable to point to your batch file. For example:GIT_EXTERNAL_DIFF=gitdiff.bat. Or through powershell by typing git config --global diff.external gitdiff.bat.

It is important to not use quotes, or specify any path information, otherwise it won't work. That's why gitdiff.bat must be in your path.

Now when you type "git diff", it will invoke your external diff viewer.

Python URLLib / URLLib2 POST

u = urllib2.urlopen('http://myserver/inout-tracker', data)
h.request('POST', '/inout-tracker/index.php', data, headers)

Using the path /inout-tracker without a trailing / doesn't fetch index.php. Instead the server will issue a 302 redirect to the version with the trailing /.

Doing a 302 will typically cause clients to convert a POST to a GET request.

Get push notification while App in foreground iOS

Here is the code to receive Push Notification when app in active state (foreground or open). UNUserNotificationCenter documentation

@available(iOS 10.0, *)
func userNotificationCenter(center: UNUserNotificationCenter, willPresentNotification notification: UNNotification, withCompletionHandler completionHandler: (UNNotificationPresentationOptions) -> Void)
{
     completionHandler([UNNotificationPresentationOptions.Alert,UNNotificationPresentationOptions.Sound,UNNotificationPresentationOptions.Badge])
}

If you need to access userInfo of notification use code: notification.request.content.userInfo

Strange Characters in database text: Ã, Ã, ¢, â‚ €,

This is surely an encoding problem. You have a different encoding in your database and in your website and this fact is the cause of the problem. Also if you ran that command you have to change the records that are already in your tables to convert those character in UTF-8.

Update: Based on your last comment, the core of the problem is that you have a database and a data source (the CSV file) which use different encoding. Hence you can convert your database in UTF-8 or, at least, when you get the data that are in the CSV, you have to convert them from UTF-8 to latin1.

You can do the convertion following this articles:

C#, Looping through dataset and show each record from a dataset column

DateTime TaskStart = DateTime.Parse(dr["TaskStart"].ToString());

An unhandled exception of type 'System.TypeInitializationException' occurred in EntityFramework.dll

Just go to Web.Config from Main folder, not the one in Views Folder:

configSections

section name="entityFramework" type="System.Data. .....,Version=" <strong>5</strong>.0.0.0"..

<..>

ADJUST THE VERSION OF EntityFramework you have installed, ex. like Version 6.0.0.0"

How to check if array element exists or not in javascript?

I had to wrap techfoobar's answer in a try..catch block, like so:

try {
  if(typeof arrayName[index] == 'undefined') {
    // does not exist
  }
  else {
  // does exist
  }
} 
catch (error){ /* ignore */ }

...that's how it worked in chrome, anyway (otherwise, the code stopped with an error).

How to use Checkbox inside Select Option

Try multiple-select, especially multiple-items. Looks to be much clean and managed solution, with tons of examples. You can also view the source.

<div>
  <div class="form-group row">
    <label class="col-sm-2">
      Basic Select
    </label>

    <div class="col-sm-10">
      <select multiple="multiple">
        <option value="1">1</option>
        <option value="2">2</option>
      </select>
    </div>
  </div>

  <div class="form-group row">
    <label class="col-sm-2">
      Group Select
    </label>

    <div class="col-sm-10">
      <select multiple="multiple">
        <optgroup label="Group 1">
          <option value="1">1</option>
          <option value="2">2</option>
        </optgroup>
        <optgroup label="Group 2">
          <option value="6">6</option>
          <option value="7">7</option>
        </optgroup>
        <optgroup label="Group 3">
          <option value="11">11</option>
          <option value="12">12</option>
        </optgroup>
      </select>
    </div>
  </div>
</div>

<script>
  $(function() {
    $('select').multipleSelect({
      multiple: true,
      multipleWidth: 60
    })
  })
</script>

firefox proxy settings via command line

I don't think there is a direct way to set the proxy (on Windows).

You could however install an add-on like FoxyProxy, create several configurations for different proxies and prior to starting FireFox move the appropriate configuration to the correct folder in your FireFox profile (using a batch file).

Jquery, checking if a value exists in array or not

http://api.jquery.com/jQuery.inArray/

if ($.inArray('example', myArray) != -1)
{
  // found it
}

Plot two graphs in same plot in R

You can also use par and plot on the same graph but different axis. Something as follows:

plot( x, y1, type="l", col="red" )
par(new=TRUE)
plot( x, y2, type="l", col="green" )

If you read in detail about par in R, you will be able to generate really interesting graphs. Another book to look at is Paul Murrel's R Graphics.

Turn off textarea resizing

Try this CSS to disable resizing

The CSS to disable resizing for all textareas looks like this:

textarea {
    resize: none;
}

You could instead just assign it to a single textarea by name (where the textarea HTML is ):

textarea[name=foo] {
    resize: none;
}

Or by id (where the textarea HTML is ):

#foo {
    resize: none;
}

Taken from: http://www.electrictoolbox.com/disable-textarea-resizing-safari-chrome/

Thymeleaf using path variables to th:href

I was trying to go through a list of objects, display them as rows in a table, with each row being a link. This worked for me. Hope it helps.

// CUSTOMER_LIST is a model attribute
<table>
    <th:block th:each="customer : ${CUSTOMER_LIST}">
        <tr>
            <td><a th:href="@{'/main?id=' + ${customer.id}}" th:text="${customer.fullName}" /></td>
        </tr>
    </th:block>
</table>

Intellij reformat on file save

If you're developing in Flutter, there's a new experimental option as of 5/1/2018 that allows you to format code on save.

How to get a .csv file into R?

As Dirk said, the function you are after is 'read.csv' or one of the other read.table variants. Given your sample data above, I think you will want to do something like this:

setwd("c:/random/directory")

df <- read.csv("myRandomFile.csv", header=TRUE)

All we did in the above was set the directory to where your .csv file is and then read the .csv into a dataframe named df. You can check that the data loaded properly by checking the structure of the object with:

str(df)

Assuming the data loaded properly, you can think go on to perform any number of statistical methods with the data in your data frame. I think summary(df) would be a good place to start. Learning how to use the help in R will be immensely useful, and a quick read through the help on CRAN will save you lots of time in the future: http://cran.r-project.org/

TypeError: a bytes-like object is required, not 'str' when writing to a file in Python3

Like it has been already mentioned, you are reading the file in binary mode and then creating a list of bytes. In your following for loop you are comparing string to bytes and that is where the code is failing.

Decoding the bytes while adding to the list should work. The changed code should look as follows:

with open(fname, 'rb') as f:
    lines = [x.decode('utf8').strip() for x in f.readlines()]

The bytes type was introduced in Python 3 and that is why your code worked in Python 2. In Python 2 there was no data type for bytes:

>>> s=bytes('hello')
>>> type(s)
<type 'str'>

Upgrade version of Pandas

According to an article on Medium, this will work:

install --upgrade pandas==1.0.0rc0

Error handling with try and catch in Laravel

You are inside a namespace so you should use \Exception to specify the global namespace:

try {

  $this->buildXMLHeader();

} catch (\Exception $e) {

    return $e->getMessage();
}

In your code you've used catch (Exception $e) so Exception is being searched in/as:

App\Services\PayUService\Exception

Since there is no Exception class inside App\Services\PayUService so it's not being triggered. Alternatively, you can use a use statement at the top of your class like use Exception; and then you can use catch (Exception $e).

How can you have SharePoint Link Lists default to opening in a new window?

You can edit the page in SharePoint designer, convert the List View web part to an XSLT Data View. (by right click + "Convert to XSLT Data View").
Then you can edit the XSLT - find the A tag and add an attribute target="_blank"

Executing multiple commands from a Windows cmd script

I have just been doing the exact same(ish) task of creating a batch script to run maven test scripts. The problem is that calling maven scrips with mvn clean install ... is itself a script and so needs to be done with call mvn clean install.

Code that will work

rem run a maven clean install
cd C:\rbe-ui-test-suite 
call mvn clean install
rem now run through all the test scripts
call mvn clean install -Prun-integration-tests -Dpattern=tc-login
call mvn clean install -Prun-integration-tests -Dpattern=login-1

Note rather the use of call. This will allow the use of consecutive maven scripts in the batch file.

NSURLErrorDomain error codes description

The NSURLErrorDomain error codes are listed here https://developer.apple.com/documentation/foundation/1508628-url_loading_system_error_codes

However, 400 is just the http status code (http://www.w3.org/Protocols/HTTP/HTRESP.html) being returned which means you've got something wrong with your request.

How do you iterate through every file/directory recursively in standard C++?

You don't. The C++ standard has no concept of directories. It is up to the implementation to turn a string into a file handle. The contents of that string and what it maps to is OS dependent. Keep in mind that C++ can be used to write that OS, so it gets used at a level where asking how to iterate through a directory is not yet defined (because you are writing the directory management code).

Look at your OS API documentation for how to do this. If you need to be portable, you will have to have a bunch of #ifdefs for various OSes.

How do I replace part of a string in PHP?

This is probably what you need:

$text = str_replace(' ', '_', substr($text, 0, 10));

Change Oracle port from port 8080

Oracle (database) can use many ports. when you install the software it scans for free ports and decides which port to use then.

The database listener defaults to 1520 but will use 1521 or 1522 if 1520 is not available. This can be adjusted in the listener.ora files.

The Enterprise Manager, web-based database administration tool defaults to port 80 but will use 8080 if 80 is not available.

See here for details on how to change the port number for enterprise manager: http://download-uk.oracle.com/docs/cd/B14099_19/integrate.1012/b19370/manage_oem.htm#i1012853

Check if a string matches a regex in Bash script

A good way to test if a string is a correct date is to use the command date:

if date -d "${DATE}" >/dev/null 2>&1
then
  # do what you need to do with your date
else
  echo "${DATE} incorrect date" >&2
  exit 1
fi

from comment: one can use formatting

if [ "2017-01-14" == $(date -d "2017-01-14" '+%Y-%m-%d') ]

How can I check if a URL exists via PHP?

All above solutions + extra sugar. (Ultimate AIO solution)

/**
 * Check that given URL is valid and exists.
 * @param string $url URL to check
 * @return bool TRUE when valid | FALSE anyway
 */
function urlExists ( $url ) {
    // Remove all illegal characters from a url
    $url = filter_var($url, FILTER_SANITIZE_URL);

    // Validate URI
    if (filter_var($url, FILTER_VALIDATE_URL) === FALSE
        // check only for http/https schemes.
        || !in_array(strtolower(parse_url($url, PHP_URL_SCHEME)), ['http','https'], true )
    ) {
        return false;
    }

    // Check that URL exists
    $file_headers = @get_headers($url);
    return !(!$file_headers || $file_headers[0] === 'HTTP/1.1 404 Not Found');
}

Example:

var_dump ( urlExists('http://stackoverflow.com/') );
// Output: true;

Formatting Decimal places in R

The function formatC() can be used to format a number to two decimal places. Two decimal places are given by this function even when the resulting values include trailing zeros.

How to Parse JSON Array with Gson

You can parse the JSONArray directly, don't need to wrap your Post class with PostEntity one more time and don't need new JSONObject().toString() either:

Gson gson = new Gson();
String jsonOutput = "Your JSON String";
Type listType = new TypeToken<List<Post>>(){}.getType();
List<Post> posts = gson.fromJson(jsonOutput, listType);

Hope that helps.

How to fix the "java.security.cert.CertificateException: No subject alternative names present" error?

my problem with getting this error was resolved by using the full URL "qatest.ourCompany.com/webService" instead of just "qatest/webService". Reason was that our security certificate had a wildcard i.e. "*.ourCompany.com". Once I put in the full address the exception went away. Hope this helps.

How do you disable viewport zooming on Mobile Safari?

Using the CSS touch-action property is the most elegant solution. Tested on iOS 13.5 and iOS 14.

To disable pinch zoom gestures and and double-tap to zoom:

body {
  touch-action: pan-x pan-y;
}

If your app also has no need for panning, i.e. scrolling, use this:

body {
  touch-action: none;
}

How do I import modules or install extensions in PostgreSQL 9.1+?

Postgrseql 9.1 provides for a new command CREATE EXTENSION. You should use it to install modules.

Modules provided in 9.1 can be found here.. The include,

adminpack , auth_delay , auto_explain , btree_gin , btree_gist
, chkpass , citext , cube , dblink , dict_int
, dict_xsyn , dummy_seclabel , earthdistance , file_fdw , fuzzystrmatch
, hstore , intagg , intarray , isn , lo
, ltree , oid2name , pageinspect , passwordcheck , pg_archivecleanup
, pgbench , pg_buffercache , pgcrypto , pg_freespacemap , pgrowlocks
, pg_standby , pg_stat_statements , pgstattuple , pg_test_fsync , pg_trgm
, pg_upgrade , seg , sepgsql , spi , sslinfo , tablefunc
, test_parser , tsearch2 , unaccent , uuid-ossp , vacuumlo
, xml2

If for instance you wanted to install earthdistance, simply use this command:

CREATE EXTENSION earthdistance;

If you wanted to install an extension with a hyphen in its name, like uuid-ossp, you need to enclose the extension name in double quotes:

CREATE EXTENSION "uuid-ossp";

Read more about contrib, and the modules available in 9.1.
Read about the new extension infrastructure, and the SQL commands to manage it here You can now more easily uninstall a module, see DROP EXTENSION. You can also get an extension list, and there is basic support for version numbers.

How to fix Python indentation

Using Vim, it shouldn't be more involved than hitting Esc, and then typing...

:%s/\t/    /g

...on the file you want to change. That will convert all tabs to four spaces. If you have inconsistent spacing as well, then that will be more difficult.

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

If you want to take into consideration the platform (x64, x86 etc) and the configuration (Debug or Release) it would be something like this:

xcopy "$(SolutionDir)\$(Platform)\$(Configuration)\$(TargetName).dll" "$(SolutionDir)TestDirectory\bin\$(Platform)\$(Configuration)\" /F /Y

Replace new line/return with space using regex

Your regex is good altough I would replace it with the empty string

String resultString = subjectString.replaceAll("[\t\n\r]", "");

You expect a space between "text." and "And" right?

I get that space when I try the regex by copying your sample

"This is my text. "

So all is well here. Maybe if you just replace it with the empty string it will work. I don't know why you replace it with \s. And the alternation | is not necessary in a character class.

Download and install an ipa from self hosted url on iOS

More simply you can utilize DropBox for this. The steps basically remain the same. You can do the following-:

1) upload your .ipa to dropBox, Share the link for this .ipa

2) Paste the shared link for .ipa in your manifest.plist file , Upload manifest file in DropBox again share the link for this .plist file

3)paste the link for this Plist in your index.html file with a suitable tag.

Share this index.html file with anybody who can tap on the URL and download. or you can directly hit the URL instead.

How to replace plain URLs with links?

Correct URL detection with international domains & astral characters support is not trivial thing. linkify-it library builds regex from many conditions, and final size is about 6 kilobytes :) . It's more accurate than all libs, currently referenced in accepted answer.

See linkify-it demo to check live all edge cases and test your ones.

If you need to linkify HTML source, you should parse it first, and iterate each text token separately.

Changing the space between each item in Bootstrap navbar

As of Bootstrap 4, you can use the spacing utilities.

Add for instance px-2 in the classes of the nav-item to increase the padding.

List comprehension with if statement

You put the if at the end:

[y for y in a if y not in b]

List comprehensions are written in the same order as their nested full-specified counterparts, essentially the above statement translates to:

outputlist = []
for y in a:
    if y not in b:
        outputlist.append(y)

Your version tried to do this instead:

outputlist = []
if y not in b:
    for y in a:
        outputlist.append(y)

but a list comprehension must start with at least one outer loop.

SSH to AWS Instance without key pairs

AWS added a new feature to connect to instance without any open port, the AWS SSM Session Manager. https://aws.amazon.com/blogs/aws/new-session-manager/

I've created a neat SSH ProxyCommand script that temporary adds your public ssh key to target instance during connection to target instance. The nice thing about this is you will connect without the need to add the ssh(22) port to your security groups, because the ssh connection is tunneled through ssm session manager.

AWS SSM SSH ProxyComand -> https://gist.github.com/qoomon/fcf2c85194c55aee34b78ddcaa9e83a1

Best way to parse RSS/Atom feeds with PHP

Another great free parser - http://bncscripts.com/free-php-rss-parser/ It's very light ( only 3kb ) and simple to use!

EntityType has no key defined error

You don't have to use key attribute all the time. Make sure the mapping file properly addressed the key

this.HasKey(t => t.Key);
this.ToTable("PacketHistory");
this.Property(p => p.Key)
            .HasColumnName("PacketHistorySK");

and don't forget to add the mapping in the Repository's OnModelCreating

modelBuilder.Configurations.Add(new PacketHistoryMap());

How do I kill a process using Vb.NET or C#?

You can bypass the security concerns, and create a much politer application by simply checking if the Word process is running, and asking the user to close it, then click a 'Continue' button in your app. This is the approach taken by many installers.

private bool isWordRunning() 
{
    return System.Diagnostics.Process.GetProcessesByName("winword").Length > 0;
}

Of course, you can only do this if your app has a GUI

dyld: Library not loaded ... Reason: Image not found

For anyone that might still be having this problem:

This is an ongoing problem on Apple's side, and what worked for me is upgrading to ios 13.4(beta). Installed that and worked like a charm.

Using JSON POST Request

An example using jQuery is below. Hope this helps

<!DOCTYPE html PUBLIC "-//W3C//DTD XHTML 1.0 Transitional//EN" "http://www.w3.org/TR/xhtml1/DTD/xhtml1-transitional.dtd">
<html>
<title>My jQuery JSON Web Page</title>
<head>
<script type="text/javascript" src="https://ajax.googleapis.com/ajax/libs/jquery/1.7.2/jquery.min.js"></script>
<script type="text/javascript">

JSONTest = function() {

    var resultDiv = $("#resultDivContainer");

    $.ajax({
        url: "https://example.com/api/",
        type: "POST",
        data: { apiKey: "23462", method: "example", ip: "208.74.35.5" },
        dataType: "json",
        success: function (result) {
            switch (result) {
                case true:
                    processResponse(result);
                    break;
                default:
                    resultDiv.html(result);
            }
        },
        error: function (xhr, ajaxOptions, thrownError) {
        alert(xhr.status);
        alert(thrownError);
        }
    });
};

</script>
</head>
<body>

<h1>My jQuery JSON Web Page</h1>

<div id="resultDivContainer"></div>

<button type="button" onclick="JSONTest()">JSON</button>

</body>
</html>

Firebug debug process

Firebug XHR debug process

How to get an isoformat datetime string including the default timezone?

You can do it in Python 2.7+ with python-dateutil (which is insalled on Mac by default):

>>> from datetime import datetime
>>> from dateutil.tz import tzlocal
>>> datetime.now(tzlocal()).isoformat()
'2016-10-22T12:45:45.353489-03:00'

Or you if you want to convert from an existed stored string:

>>> from datetime import datetime
>>> from dateutil.tz import tzlocal
>>> from dateutil.parser import parse
>>> parse("2016-10-21T16:33:27.696173").replace(tzinfo=tzlocal()).isoformat()
'2016-10-21T16:33:27.696173-03:00' <-- Atlantic Daylight Time (ADT) 
>>> parse("2016-01-21T16:33:27.696173").replace(tzinfo=tzlocal()).isoformat()
'2016-01-21T16:33:27.696173-04:00' <-- Atlantic Standard Time (AST)

Hashset vs Treeset

1.HashSet allows null object.

2.TreeSet will not allow null object. If you try to add null value it will throw a NullPointerException.

3.HashSet is much faster than TreeSet.

e.g.

 TreeSet<String> ts = new TreeSet<String>();
 ts.add(null); // throws NullPointerException

 HashSet<String> hs = new HashSet<String>();
 hs.add(null); // runs fine

How to extract the year from a Python datetime object?

The other answers to this question seem to hit it spot on. Now how would you figure this out for yourself without stack overflow? Check out IPython, an interactive Python shell that has tab auto-complete.

> ipython
import Python 2.5 (r25:51908, Nov  6 2007, 16:54:01)
Type "copyright", "credits" or "license" for more information.

IPython 0.8.2.svn.r2750 -- An enhanced Interactive Python.
?         -> Introduction and overview of IPython's features.
%quickref -> Quick reference.
help      -> Python's own help system.
object?   -> Details about 'object'. ?object also works, ?? prints more.

In [1]: import datetime
In [2]: now=datetime.datetime.now()
In [3]: now.

press tab a few times and you'll be prompted with the members of the "now" object:

now.__add__           now.__gt__            now.__radd__          now.__sub__           now.fromordinal       now.microsecond       now.second            now.toordinal         now.weekday
now.__class__         now.__hash__          now.__reduce__        now.astimezone        now.fromtimestamp     now.min               now.strftime          now.tzinfo            now.year
now.__delattr__       now.__init__          now.__reduce_ex__     now.combine           now.hour              now.minute            now.strptime          now.tzname
now.__doc__           now.__le__            now.__repr__          now.ctime             now.isocalendar       now.month             now.time              now.utcfromtimestamp
now.__eq__            now.__lt__            now.__rsub__          now.date              now.isoformat         now.now               now.timetuple         now.utcnow
now.__ge__            now.__ne__            now.__setattr__       now.day               now.isoweekday        now.replace           now.timetz            now.utcoffset
now.__getattribute__  now.__new__           now.__str__           now.dst               now.max               now.resolution        now.today             now.utctimetuple

and you'll see that now.year is a member of the "now" object.

C fopen vs open

Using open, read, write means you have to worry about signal interaptions.

If the call was interrupted by a signal handler the functions will return -1 and set errno to EINTR.

So the proper way to close a file would be

while (retval = close(fd), retval == -1 && ernno == EINTR) ;

Python Pandas Counting the Occurrences of a Specific value

Couple of ways using count or sum

In [338]: df
Out[338]:
  col1 education
0    a       9th
1    b       9th
2    c       8th

In [335]: df.loc[df.education == '9th', 'education'].count()
Out[335]: 2

In [336]: (df.education == '9th').sum()
Out[336]: 2

In [337]: df.query('education == "9th"').education.count()
Out[337]: 2

Math constant PI value in C

The closest thing C does to "computing p" in a way that's directly visible to applications is acos(-1) or similar. This is almost always done with polynomial/rational approximations for the function being computed (either in C, or by the FPU microcode).

However, an interesting issue is that computing the trigonometric functions (sin, cos, and tan) requires reduction of their argument modulo 2p. Since 2p is not a diadic rational (and not even rational), it cannot be represented in any floating point type, and thus using any approximation of the value will result in catastrophic error accumulation for large arguments (e.g. if x is 1e12, and 2*M_PI differs from 2p by e, then fmod(x,2*M_PI) differs from the correct value of 2p by up to 1e12*e/p times the correct value of x mod 2p. That is to say, it's completely meaningless.

A correct implementation of C's standard math library simply has a gigantic very-high-precision representation of p hard coded in its source to deal with the issue of correct argument reduction (and uses some fancy tricks to make it not-quite-so-gigantic). This is how most/all C versions of the sin/cos/tan functions work. However, certain implementations (like glibc) are known to use assembly implementations on some cpus (like x86) and don't perform correct argument reduction, leading to completely nonsensical outputs. (Incidentally, the incorrect asm usually runs about the same speed as the correct C code for small arguments.)

Upload video files via PHP and save them in appropriate folder and have a database entry

HTML Code

<html>
<body>

<head>
<title></title>
</head>

<body>

<form action="upload.php" method="post" enctype="multipart/form-data">
    <label for="file"><span>Filename:</span></label>
    <input type="file" name="file" id="file" /> 
    <br />
<input type="submit" name="submit" value="Submit" />
</form>



<?php

    //============================= DATABASE CONNECTIVITY d ====================
    $servername = "localhost";
    $username = "root";
    $password = "";
    $dbname = "test";

    // Create connection
    $conn = new mysqli($servername, $username, $password, $dbname);
    // Check connection
    if ($conn->connect_error) {
        die("Connection failed: " . $conn->connect_error);
    } 
    else

    //============================= DATABASE CONNECTIVITY u ====================
    //============================= Retrieve data from DB d ====================
    $sql = "SELECT name, size, type FROM videos";
    $result = $conn->query($sql);

    if ($result->num_rows > 0) {
    // output data of each row
    while($row = $result->fetch_assoc()) 
        {
        $path = "uploaded/" . $row["name"];

            echo $path . "<br>";

        }
    } else {
        echo "0 results";
    }
    $conn->close();
    //============================= Retrieve data from DB d ====================

?>


</body>
</html>

UL list style not applying

If I'm not mistaken, you should be applying this rule to the li, not the ul.

ul li {list-style-type: disc;}

Get the POST request body from HttpServletRequest

Easy way with commons-io.

IOUtils.toString(request.getReader());

https://commons.apache.org/proper/commons-io/javadocs/api-2.5/org/apache/commons/io/IOUtils.html

Remove an item from a dictionary when its key is unknown

a = {'name': 'your_name','class': 4}
if 'name' in a: del a['name']

Check if a Windows service exists and delete in PowerShell

More recent versions of PS have Remove-WmiObject. Beware of silent fails for $service.delete() ...

PS D:\> $s3=Get-WmiObject -Class Win32_Service -Filter "Name='TSATSvrSvc03'"

PS D:\> $s3.delete()
...
ReturnValue      : 2
...
PS D:\> $?
True
PS D:\> $LASTEXITCODE
0
PS D:\> $result=$s3.delete()

PS D:\> $result.ReturnValue
2

PS D:\> Remove-WmiObject -InputObject $s3
Remove-WmiObject : Access denied 
At line:1 char:1
+ Remove-WmiObject -InputObject $s3
+ ~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~
    + CategoryInfo          : InvalidOperation: (:) [Remove-WmiObject], ManagementException
    + FullyQualifiedErrorId : RemoveWMIManagementException,Microsoft.PowerShell.Commands.RemoveWmiObject

PS D:\>

For my situation I needed to be running 'As Administrator'

Ng-model does not update controller value

I was facing same problem... The resolution that worked for me is to use this keyword..........

alert(this.ModelName);

How to get VM arguments from inside of Java application?

With this code you can get the JVM arguments:

import java.lang.management.ManagementFactory;
import java.lang.management.RuntimeMXBean;
...
RuntimeMXBean runtimeMxBean = ManagementFactory.getRuntimeMXBean();
List<String> arguments = runtimeMxBean.getInputArguments();

How to select some rows with specific rownames from a dataframe?

You can also use this:

DF[paste0("stu",c(2,3,5,9)), ]

UnicodeDecodeError: 'charmap' codec can't decode byte X in position Y: character maps to <undefined>

If file = open(filename, encoding="utf8") doesn't work, try
file = open(filename, errors="ignore"), if you want to remove unneeded characters.

HTML input field hint

I think for your situation, the easy and simple for your html input , you can probably add the attribute title

<input name="Username" value="Enter username.." type="text" size="20" maxlength="20" title="enter username">

PHP date add 5 year to current date

Its very very easy with Carbon. $date = "2016-02-16"; // Or Your date $newDate = Carbon::createFromFormat('Y-m-d', $date)->addYear(1);

MySQL query String contains

Mine is using LOCATE in mysql:

LOCATE(substr,str), LOCATE(substr,str,pos)

This function is multi-byte safe, and is case-sensitive only if at least one argument is a binary string.

In your case:

mysql_query("
SELECT * FROM `table`
WHERE LOCATE('{$needle}','column') > 0
");

Get docker container id from container name

You can try this:

docker inspect --format="{{.Id}}" container_name

This approach is OS independent.

Standard way to embed version into python package?

Using `setuptools` and `pbr`

There is not a standard way to manage version, but the standard way to manage your packages is setuptools.

The best solution I've found overall for managing version is to use setuptools with the pbr extension. This is now my standard way of managing version.

Setting up your project for full packaging may be overkill for simple projects, but if you need to manage version, you are probably at the right level to just set everything up. Doing so also makes your package releasable at PyPi so everyone can download and use it with Pip.

PBR moves most metadata out of the setup.py tools and into a setup.cfg file that is then used as a source for most metadata, which can include version. This allows the metadata to be packaged into an executable using something like pyinstaller if needed (if so, you will probably need this info), and separates the metadata from the other package management/setup scripts. You can directly update the version string in setup.cfg manually, and it will be pulled into the *.egg-info folder when building your package releases. Your scripts can then access the version from the metadata using various methods (these processes are outlined in sections below).

When using Git for VCS/SCM, this setup is even better, as it will pull in a lot of the metadata from Git so that your repo can be your primary source of truth for some of the metadata, including version, authors, changelogs, etc. For version specifically, it will create a version string for the current commit based on git tags in the repo.

PyPA - Packaging Python Packages with SetupTools - Tutorial
PBR latest build usage documentation - How to setup an 8-line setup.py and a setup.cfg file with the metadata.

As PBR will pull version, author, changelog and other info directly from your git repo, so some of the metadata in setup.cfg can be left out and auto generated whenever a distribution is created for your package (using setup.py)

Get the current version in real-time

setuptools will pull the latest info in real-time using setup.py:

python setup.py --version

This will pull the latest version either from the setup.cfg file, or from the git repo, based on the latest commit that was made and tags that exist in the repo. This command doesn't update the version in a distribution though.

Updating the version metadata

When you create a distribution with setup.py (i.e. py setup.py sdist, for example), then all the current info will be extracted and stored in the distribution. This essentially runs the setup.py --version command and then stores that version info into the package.egg-info folder in a set of files that store distribution metadata.

Note on process to update version meta-data:

If you are not using pbr to pull version data from git, then just update your setup.cfg directly with new version info (easy enough, but make sure this is a standard part of your release process).

If you are using git, and you don't need to create a source or binary distribution (using python setup.py sdist or one of the python setup.py bdist_xxx commands) the simplest way to update the git repo info into your <mypackage>.egg-info metadata folder is to just run the python setup.py install command. This will run all the PBR functions related to pulling metadata from the git repo and update your local .egg-info folder, install script executables for any entry-points you have defined, and other functions you can see from the output when you run this command.

Note that the .egg-info folder is generally excluded from being stored in the git repo itself in standard Python .gitignore files (such as from Gitignore.IO), as it can be generated from your source. If it is excluded, make sure you have a standard "release process" to get the metadata updated locally before release, and any package you upload to PyPi.org or otherwise distribute must include this data to have the correct version. If you want the Git repo to contain this info, you can exclude specific files from being ignored (i.e. add !*.egg-info/PKG_INFO to .gitignore)

Accessing the version from a script

You can access the metadata from the current build within Python scripts in the package itself. For version, for example, there are several ways to do this I have found so far:

## This one is a new built-in as of Python 3.8.0 should become the standard
from importlib-metadata import version

v0 = version("mypackage")
print('v0 {}'.format(v0))

## I don't like this one because the version method is hidden
import pkg_resources  # part of setuptools

v1 = pkg_resources.require("mypackage")[0].version
print('v1 {}'.format(v1))

# Probably best for pre v3.8.0 - the output without .version is just a longer string with
# both the package name, a space, and the version string
import pkg_resources  # part of setuptools

v2 = pkg_resources.get_distribution('mypackage').version
print('v2 {}'.format(v2))

## This one seems to be slower, and with pyinstaller makes the exe a lot bigger
from pbr.version import VersionInfo

v3 = VersionInfo('mypackage').release_string()
print('v3 {}'.format(v3))

You can put one of these directly in your __init__.py for the package to extract the version info as follows, similar to some other answers:

__all__ = (
    '__version__',
    'my_package_name'
)

import pkg_resources  # part of setuptools

__version__ = pkg_resources.get_distribution("mypackage").version

Address already in use: JVM_Bind

as the exception says there is already another server running on the same port. you can either kill that service or change glassfish to run on another poet

Use CSS to remove the space between images

An easy way that is compatible pretty much everywhere is to set font-size: 0 on the container, provided you don't have any descendent text nodes you need to style (though it is trivial to override this where needed).

.nospace {
   font-size: 0;
}

jsFiddle.

You could also change from the default display: inline into block or inline-block. Be sure to use the workarounds required for <= IE7 (and possibly ancient Firefoxes) for inline-block to work.

How can I check if a program exists from a Bash script?

Expanding on @lhunath's and @GregV's answers, here's the code for the people who want to easily put that check inside an if statement:

exists()
{
  command -v "$1" >/dev/null 2>&1
}

Here's how to use it:

if exists bash; then
  echo 'Bash exists!'
else
  echo 'Your system does not have Bash'
fi

Recursively list all files in a directory including files in symlink directories

I knew tree was an appropriate, but I didn't have tree installed. So, I got a pretty close alternate here

find ./ | sed -e 's/[^-][^\/]*\//--/g;s/--/ |-/'

How do I remove a substring from the end of a string in Python?

Python >= 3.9:

'abcdc.com'.removesuffix('.com')

Python < 3.9:

def remove_suffix(text, suffix):
    if text.endswith(suffix):
        text = text[:-len(suffix)]
    return text

remove_suffix('abcdc.com', '.com')

Request header field Access-Control-Allow-Headers is not allowed by Access-Control-Allow-Headers

this is backend problem. if use sails api on backend change cors.js and add your filed here

module.exports.cors = {
  allRoutes: true,
  origin: '*',
  credentials: true,
  methods: 'GET, POST, PUT, DELETE, OPTIONS, HEAD',
  headers: 'Origin, X-Requested-With, Content-Type, Accept, Engaged-Auth-Token'
};

How can I make a "color map" plot in matlab?

By default mesh will color surface values based on the (default) jet colormap (i.e. hot is higher). You can additionally use surf for filled surface patches and set the 'EdgeColor' property to 'None' (so the patch edges are non-visible).

[X,Y] = meshgrid(-8:.5:8);
R = sqrt(X.^2 + Y.^2) + eps;
Z = sin(R)./R;

% surface in 3D
figure;
surf(Z,'EdgeColor','None');

enter image description here

2D map: You can get a 2D map by switching the view property of the figure

% 2D map using view
figure;
surf(Z,'EdgeColor','None');
view(2);

enter image description here

... or treating the values in Z as a matrix, viewing it as a scaled image using imagesc and selecting an appropriate colormap.

% using imagesc to view just Z
figure;
imagesc(Z); 
colormap jet;

enter image description here

The color pallet of the map is controlled by colormap(map), where map can be custom or any of the built-in colormaps provided by MATLAB:

enter image description here

Update/Refining the map: Several design options on the map (resolution, smoothing, axis etc.) can be controlled by the regular MATLAB options. As @Floris points out, here is a smoothed, equal-axis, no-axis labels maps, adapted to this example:

figure;
surf(X, Y, Z,'EdgeColor', 'None', 'facecolor', 'interp');
view(2);
axis equal; 
axis off;

enter image description here

Conversion from byte array to base64 and back

The reason the encoded array is longer by about a quarter is that base-64 encoding uses only six bits out of every byte; that is its reason of existence - to encode arbitrary data, possibly with zeros and other non-printable characters, in a way suitable for exchange through ASCII-only channels, such as e-mail.

The way you get your original array back is by using Convert.FromBase64String:

 byte[] temp_backToBytes = Convert.FromBase64String(temp_inBase64);

How do I build JSON dynamically in javascript?

First, I think you're calling it the wrong thing. "JSON" stands for "JavaScript Object Notation" - it's just a specification for representing some data in a string that explicitly mimics JavaScript object (and array, string, number and boolean) literals. You're trying to build up a JavaScript object dynamically - so the word you're looking for is "object".

With that pedantry out of the way, I think that you're asking how to set object and array properties.

// make an empty object
var myObject = {};

// set the "list1" property to an array of strings
myObject.list1 = ['1', '2'];

// you can also access properties by string
myObject['list2'] = [];
// accessing arrays is the same, but the keys are numbers
myObject.list2[0] = 'a';
myObject['list2'][1] = 'b';

myObject.list3 = [];
// instead of placing properties at specific indices, you
// can push them on to the end
myObject.list3.push({});
// or unshift them on to the beginning
myObject.list3.unshift({});
myObject.list3[0]['key1'] = 'value1';
myObject.list3[1]['key2'] = 'value2';

myObject.not_a_list = '11';

That code will build up the object that you specified in your question (except that I call it myObject instead of myJSON). For more information on accessing properties, I recommend the Mozilla JavaScript Guide and the book JavaScript: The Good Parts.

What is a C++ delegate?

A delegate is a class that wraps a pointer or reference to an object instance, a member method of that object's class to be called on that object instance, and provides a method to trigger that call.

Here's an example:

template <class T>
class CCallback
{
public:
    typedef void (T::*fn)( int anArg );

    CCallback(T& trg, fn op)
        : m_rTarget(trg)
        , m_Operation(op)
    {
    }

    void Execute( int in )
    {
        (m_rTarget.*m_Operation)( in );
    }

private:

    CCallback();
    CCallback( const CCallback& );

    T& m_rTarget;
    fn m_Operation;

};

class A
{
public:
    virtual void Fn( int i )
    {
    }
};


int main( int /*argc*/, char * /*argv*/ )
{
    A a;
    CCallback<A> cbk( a, &A::Fn );
    cbk.Execute( 3 );
}

Fastest way to zero out a 2d array in C?

If array is truly an array, then you can "zero it out" with:

memset(array, 0, sizeof array);

But there are two points you should know:

this works only if array is really a "two-d array", i.e., was declared T array[M][N]; for some type T.
it works only in the scope where array was declared. If you pass it to a function, then the name array decays to a pointer, and sizeof will not give you the size of the array.

Let's do an experiment:

#include <stdio.h>

void f(int (*arr)[5])
{
    printf("f:    sizeof arr:       %zu\n", sizeof arr);
    printf("f:    sizeof arr[0]:    %zu\n", sizeof arr[0]);
    printf("f:    sizeof arr[0][0]: %zu\n", sizeof arr[0][0]);
}

int main(void)
{
    int arr[10][5];
    printf("main: sizeof arr:       %zu\n", sizeof arr);
    printf("main: sizeof arr[0]:    %zu\n", sizeof arr[0]);
    printf("main: sizeof arr[0][0]: %zu\n\n", sizeof arr[0][0]);
    f(arr);
    return 0;
}

On my machine, the above prints:

main: sizeof arr:       200
main: sizeof arr[0]:    20
main: sizeof arr[0][0]: 4

f:    sizeof arr:       8
f:    sizeof arr[0]:    20
f:    sizeof arr[0][0]: 4

Even though arr is an array, it decays to a pointer to its first element when passed to f(), and therefore the sizes printed in f() are "wrong". Also, in f() the size of arr[0] is the size of the array arr[0], which is an "array [5] of int". It is not the size of an int *, because the "decaying" only happens at the first level, and that is why we need to declare f() as taking a pointer to an array of the correct size.

So, as I said, what you were doing originally will work only if the two conditions above are satisfied. If not, you will need to do what others have said:

memset(array, 0, m*n*sizeof array[0][0]);

Finally, memset() and the for loop you posted are not equivalent in the strict sense. There could be (and have been) compilers where "all bits zero" does not equal zero for certain types, such as pointers and floating-point values. I doubt that you need to worry about that though.

How to hide collapsible Bootstrap 4 navbar on click

You can add the collapse component to the links like this..

<ul class="navbar-nav mr-auto">
     <li class="nav-item active">
         <a class="nav-link" href="#home" data-toggle="collapse" data-target=".navbar-collapse.show">Home <span class="sr-only">(current)</span></a>
     </li>
     <li class="nav-item">
         <a class="nav-link" href="#about-us" data-toggle="collapse" data-target=".navbar-collapse.show">About</a>
     </li>
     <li class="nav-item">
         <a class="nav-link" href="#pricing" data-toggle="collapse" data-target=".navbar-collapse.show">Pricing</a>
     </li>
 </ul>

BS3 demo using 'data-toggle' method

Or, (perhaps a better way) use jQuery like this..

$('.navbar-nav>li>a').on('click', function(){
    $('.navbar-collapse').collapse('hide');
});

BS3 demo using jQuery method

Update 2019 - Bootstrap 4

The navbar has changed, but the "close after click" method is still the same:

BS4 demo jQuery method
BS4 demo data-toggle method

Update 2021 - Bootstrap 5 (beta)

Use javascript to add a click event listener on the menu items to close the Collapse navbar..

const navLinks = document.querySelectorAll('.nav-item')
const menuToggle = document.getElementById('navbarSupportedContent')
const bsCollapse = new bootstrap.Collapse(menuToggle)
navLinks.forEach((l) => {
    l.addEventListener('click', () => { bsCollapse.toggle() })
})

BS5 demo javascript method

Or, Use the data-bs-toggle and data-bs-target data attributes in the markup on each link to toggle the Collapse navbar...

<nav class="navbar navbar-expand-lg navbar-light bg-light">
    <div class="container">
        <a class="navbar-brand" href="#">Navbar</a>
        <button class="navbar-toggler" type="button" data-bs-toggle="collapse" data-bs-target="#navbarSupportedContent" aria-controls="navbarSupportedContent" aria-expanded="false" aria-label="Toggle navigation">
            <span class="navbar-toggler-icon"></span>
        </button>
        <div class="collapse navbar-collapse" id="navbarSupportedContent">
            <ul class="navbar-nav me-auto">
                <li class="nav-item active">
                    <a class="nav-link" href="#" data-bs-toggle="collapse" data-bs-target=".navbar-collapse.show">Home</a>
                </li>
                <li class="nav-item">
                    <a class="nav-link" href="#" data-bs-toggle="collapse" data-bs-target=".navbar-collapse.show">Link</a>
                </li>
                <li class="nav-item">
                    <a class="nav-link disabled" href="#" data-bs-toggle="collapse" data-bs-target=".navbar-collapse.show">Disabled</a>
                </li>
            </ul>
            <form class="d-flex my-2 my-lg-0">
                <input class="form-control me-sm-2" type="search" placeholder="Search" aria-label="Search">
                <button class="btn btn-outline-success my-2 my-sm-0" type="submit">Search</button>
            </form>
        </div>
    </div>
</nav>

BS5 demo data-attributes method

pip install fails with "connection error: [SSL: CERTIFICATE_VERIFY_FAILED] certificate verify failed (_ssl.c:598)"

In my case, I was running Python in the minimal alpine docker image. It was missing root CA certificates. Fix:

apk update && apk add ca-certificates

Convert a double to a QString

Check out the documentation

Quote:

QString provides many functions for converting numbers into strings and strings into numbers. See the arg() functions, the setNum() functions, the number() static functions, and the toInt(), toDouble(), and similar functions.

Difference between parameter and argument

They are often used interchangeably in text, but in most standards the distinction is that an argument is an expression passed to a function, where a parameter is a reference declared in a function declaration.

How to add property to a class dynamically?

Something that works for me is this:

class C:
    def __init__(self):
        self._x=None

    def g(self):
        return self._x

    def s(self, x):
        self._x = x

    def d(self):
        del self._x

    def s2(self,x):
        self._x=x+x

    x=property(g,s,d)


c = C()
c.x="a"
print(c.x)

C.x=property(C.g, C.s2)
C.x=C.x.deleter(C.d)
c2 = C()
c2.x="a"
print(c2.x)

Output

a
aa

Replace specific text with a redacted version using Python

You can do it using named-entity recognition (NER). It's fairly simple and there are out-of-the-shelf tools out there to do it, such as spaCy.

NER is an NLP task where a neural network (or other method) is trained to detect certain entities, such as names, places, dates and organizations.

Example:

Sponge Bob went to South beach, he payed a ticket of $200!
I know, Michael is a good person, he goes to McDonalds, but donates to charity at St. Louis street.

Returns:

Just be aware that this is not 100%!

Here are a little snippet for you to try out:

import spacy

phrases = ['Sponge Bob went to South beach, he payed a ticket of $200!', 'I know, Michael is a good person, he goes to McDonalds, but donates to charity at St. Louis street.']
nlp = spacy.load('en')
for phrase in phrases:
   doc = nlp(phrase)
   replaced = ""
   for token in doc:
      if token in doc.ents:
         replaced+="XXXX "
      else:
         replaced+=token.text+" "

You could, instead of replacing with XXXX, replace based on the entity type, like:

if ent.label_ == "PERSON":
   replaced += "<PERSON> "

Then:

import re, random

personames = ["Jack", "Mike", "Bob", "Dylan"]

phrase = re.replace("<PERSON>", random.choice(personames), phrase)

WCF gives an unsecured or incorrectly secured fault error

In my case I was using certificates for authentication with certificateValidationMode set to "PeerTrust" and I had forgotten to install the client certificate in windows store (LocalMachine\TrustedPeople) to make it accepted by the server.

Bootstrap 3 - 100% height of custom div inside column

You need to set the height of every parent element of the one you want the height defined.

<html style="height: 100%;">
  <body style="height: 100%;">
    <div style="height: 100%;">
      <p>
        Make this division 100% height.
      </p>
    </div>
  </body>
</html>

Article.

JsFiddle example

How to discard local changes in an SVN checkout?

How to dynamically add a style for text-align using jQuery

$(this).css("text-align", "center"); should work, make sure 'this' is the element you're actually trying to set the text-align style to.

Java ArrayList of Arrays?

BTW. you should prefer coding against an Interface.

private ArrayList<String[]> action = new ArrayList<String[]>();

Should be

private List<String[]> action = new ArrayList<String[]>();

How to get the request parameters in Symfony 2?

$request = Request::createFromGlobals();
$getParameter = $request->get('getParameter');

Check if Nullable Guid is empty in c#

Note that HasValue will return true for an empty Guid.

bool validGuid = SomeProperty.HasValue && SomeProperty != Guid.Empty;

Error Running React Native App From Terminal (iOS)

1) Go to Xcode Preferences

2) Locate the location tab

3) Set the Xcode verdion in Given Command Line Tools

Now, it ll successfully work.

bootstrap 3 tabs not working properly

My problem was that I sillily concluded bootstrap documentation is the latest one.
If you are using Bootstrap 4, the necessary working tab markub is: http://v4-alpha.getbootstrap.com/components/navs/#javascript-behavior

<ul>
  <li class="nav-item"><a class="active" href="#a" data-toggle="tab">a</a></li>
  <li class="nav-item"><a                href="#b" data-toggle="tab">b</a></li>
</ul>

<div class="tab-content">
  <div class="tab-pane active" id="a">a</div>
  <div class="tab-pane"        id="b">b</div>
</div>

What is Android keystore file, and what is it used for?

Android Market requires you to sign all apps you publish with a certificate, using a public/private key mechanism (the certificate is signed with your private key). This provides a layer of security that prevents, among other things, remote attackers from pushing malicious updates to your application to market (all updates must be signed with the same key).

From The App-Signing Guide of the Android Developer's site:

In general, the recommended strategy for all developers is to sign all of your applications with the same certificate, throughout the expected lifespan of your applications. There are several reasons why you should do so...

Using the same key has a few benefits - One is that it's easier to share data between applications signed with the same key. Another is that it allows multiple apps signed with the same key to run in the same process, so a developer can build more "modular" applications.

SLF4J: Class path contains multiple SLF4J bindings

This is issue because of StaticLoggerBinder.class class belongs to two different jars. this class references from logback-classic-1.2.3.jar and same class also referenced from log4j-slf4j-impl-2.10.0.jar. both of jar in classpath. Hence there is conflict between them. This is reason of log file is not generation even though log4j2.xml file in classpath [src/main/resource].

We have so select one of jar, I recommend use log4j-slf4j-impl-2.10.0.jar file and exclude logback-classic-1.2.3.jar file. Solution: open pom file and view the dependency Hierarchy [eclipse] or run
mvn dependency:tree command to find out the dependency tree and source of dependency that download the dependency. find the conflicting dependency and exclude them. For Springboot application try this.

<dependency>
            <groupId>org.springframework.boot</groupId>
            <artifactId>spring-boot-starter-web</artifactId>
            <exclusions>
                    <exclusion>
                        <groupId>org.springframework.boot</groupId>
                        <artifactId>spring-boot-starter-logging</artifactId>
                    </exclusion>
                </exclusions>
        </dependency>
    <dependency>
            <groupId>org.springframework.boot</groupId>
            <artifactId>spring-boot-starter-actuator</artifactId>
            <exclusions>
                <exclusion>
                    <groupId>org.springframework.boot</groupId>
                    <artifactId>spring-boot-starter-logging</artifactId>
                </exclusion>
            </exclusions>
        </dependency>

This is working fine for me after struggling a lots.

Fastest way to get the first object from a queryset in django?

If you plan to get first element often - you can extend QuerySet in this direction:

class FirstQuerySet(models.query.QuerySet):
    def first(self):
        return self[0]


class ManagerWithFirstQuery(models.Manager):
    def get_query_set(self):
        return FirstQuerySet(self.model)

Define model like this:

class MyModel(models.Model):
    objects = ManagerWithFirstQuery()

And use it like this:

 first_object = MyModel.objects.filter(x=100).first()

requestFeature() must be called before adding content

Change the Compile SDK version,Target SDK version to Build Tools version to 24.0.0 in build.gradle if u face issue in request Feature

.NET - Get protocol, host, and port

Request.Url will return you the Uri of the request. Once you have that, you can retrieve pretty much anything you want. To get the protocol, call the Scheme property.

Sample:

Uri url = Request.Url;
string protocol = url.Scheme;

Hope this helps.

How to Use pdf.js

Import data into Google Colaboratory

This allows you to upload your files through Google Drive.

Run the below code (found this somewhere previously but I can't find the source again - credits to whoever wrote it!):

!apt-get install -y -qq software-properties-common python-software-properties module-init-tools
!add-apt-repository -y ppa:alessandro-strada/ppa 2>&1 > /dev/null
!apt-get update -qq 2>&1 > /dev/null
!apt-get -y install -qq google-drive-ocamlfuse fuse

from google.colab import auth
auth.authenticate_user()
from oauth2client.client import GoogleCredentials
creds = GoogleCredentials.get_application_default()
import getpass

!google-drive-ocamlfuse -headless -id={creds.client_id} -secret={creds.client_secret} < /dev/null 2>&1 | grep URL
vcode = getpass.getpass()
!echo {vcode} | google-drive-ocamlfuse -headless -id={creds.client_id} -secret={creds.client_secret}

Click on the first link that comes up which will prompt you to sign in to Google; after that another will appear which will ask for permission to access to your Google Drive.

Then, run this which creates a directory named 'drive', and links your Google Drive to it:

!mkdir -p drive
!google-drive-ocamlfuse drive

If you do a !ls now, there will be a directory drive, and if you do a !ls drive you can see all the contents of your Google Drive.

So for example, if I save my file called abc.txt in a folder called ColabNotebooks in my Google Drive, I can now access it via a path drive/ColabNotebooks/abc.txt

How to symbolicate crash log Xcode?

There is an easier way using Xcode (without using command line tools and looking up addresses one at a time)

Take any .xcarchive file. If you have one from before you can use that. If you don't have one, create one by running the Product > Archive from Xcode.
Right click on the .xcarchive file and select 'Show Package Contents'
Copy the dsym file (of the version of the app that crashed) to the dSYMs folder
Copy the .app file (of the version of the app that crashed) to the Products > Applications folder
Edit the Info.plist and edit the CFBundleShortVersionString and CFBundleVersion under the ApplicationProperties dictionary. This will help you identify the archive later
Double click the .xcarchive to import it to Xcode. It should open Organizer.
Go back to the crash log (in Devices window in Xcode)
Drag your .crash file there (if not already present)
The entire crash log should now be symbolicated. If not, then right click and select 'Re-symbolicate crash log'

How to "wait" a Thread in Android

I just add this line exactly as it appears below (if you need a second delay):

try {
    Thread.sleep(1000);
} catch(InterruptedException e) {
    // Process exception
}

I find the catch IS necessary (Your app can crash due to Android OS as much as your own code).

SVG support for Internet Explorer 8 and below

How to call Stored Procedure in Entity Framework 6 (Code-First)?

You can pass parameters to sp_GetById and fetch the results either in ToList() or FirstOrDefault();

var param  = new SqlParameter("@id", 106);
var result = dbContext
               .Database
               .SqlQuery<Category>("dbo.sp_GetById @id", param)
               .FirstOrDefault();

What's the best way to determine which version of Oracle client I'm running?

You should put a semicolon at the end of select * from v$version;.

Like this you will get all info you need...

If you are looking just for Oracle for example you can do as:

SQL> select * from v$version where banner like 'Oracle%';

"Items collection must be empty before using ItemsSource."

I ran into this problem because one level of tag, <ListView.View> to be specirfic, was missing in my XAML.

This code produced this error.

<Grid>
    <ListView Margin="10" Name="lvDataBinding" >
        <GridView>
            <GridViewColumn Header="Name" Width="120" DisplayMemberBinding="{Binding Name}" />
            <GridViewColumn Header="Age" Width="50" DisplayMemberBinding="{Binding Age}" />
            <GridViewColumn Header="Mail" Width="150" DisplayMemberBinding="{Binding Mail}" />
        </GridView>
    </ListView>
</Grid>

The following fixed it

<Grid>
    <ListView Margin="10" Name="lvDataBinding" >
        <ListView.View> <!-- This was missing in top! -->
            <GridView>
                <GridViewColumn Header="Name" Width="120" DisplayMemberBinding="{Binding Name}" />
                <GridViewColumn Header="Age" Width="50" DisplayMemberBinding="{Binding Age}" />
                <GridViewColumn Header="Mail" Width="150" DisplayMemberBinding="{Binding Mail}" />
            </GridView>
        </ListView.View>
    </ListView>
</Grid>

standard_init_linux.go:190: exec user process caused "no such file or directory" - Docker

It's a CRLF problem. I fixed the problem using this:

git config --global core.eol lf

git config --global core.autocrlf input

find . -type f -print0 | xargs -0 dos2unix

Adding values to Arraylist

Two last variants are the same, int is wrapped to Integer automatically where you need an Object. If you not write any class in <> it will be Object by default. So there is no difference, but it will be better to understanding if you write Object.

What are the most common naming conventions in C?

Here's an (apparently) uncommon one, which I've found useful: module name in CamelCase, then an underscore, then function or file-scope name in CamelCase. So for example:

Bluetooth_Init()
CommsHub_Update()
Serial_TxBuffer[]

What is the format specifier for unsigned short int?

Here is a good table for printf specifiers. So it should be %hu for unsigned short int.

And link to Wikipedia "C data types" too.

Include another JSP file

At page translation time, the content of the file given in the include directive is ‘pasted’ as it is, in the place where the JSP include directive is used. Then the source JSP page is converted into a java servlet class. The included file can be a static resource or a JSP page. Generally, JSP include directive is used to include header banners and footers.

Syntax for include a jsp file:

<%@ include file="relative url">

Example

<%@include file="page_name.jsp" %>

How to convert a table to a data frame

If you are using the tidyverse, you can use

as_data_frame(table(myvector))

to get a tibble (i.e. a data frame with some minor variations from the base class)

How to store Configuration file and read it using React

You can use the dotenv package no matter what setup you use. It allows you to create a .env in your project root and specify your keys like so

REACT_APP_SERVER_PORT=8000

In your applications entry file your just call dotenv(); before accessing the keys like so

process.env.REACT_APP_SERVER_PORT

Split output of command by columns using Bash?

Please note that the tr -s ' ' option will not remove any single leading spaces. If your column is right-aligned (as with ps pid)...

$ ps h -o pid,user -C ssh,sshd | tr -s " "
 1543 root
19645 root
19731 root

Then cutting will result in a blank line for some of those fields if it is the first column:

$ <previous command> | cut -d ' ' -f1

19645
19731

Unless you precede it with a space, obviously

$ <command> | sed -e "s/.*/ &/" | tr -s " "

Now, for this particular case of pid numbers (not names), there is a function called pgrep:

$ pgrep ssh

Shell functions

However, in general it is actually still possible to use shell functions in a concise manner, because there is a neat thing about the read command:

$ <command> | while read a b; do echo $a; done

The first parameter to read, a, selects the first column, and if there is more, everything else will be put in b. As a result, you never need more variables than the number of your column +1.

So,

while read a b c d; do echo $c; done

will then output the 3rd column. As indicated in my comment...

A piped read will be executed in an environment that does not pass variables to the calling script.

out=$(ps whatever | { read a b c d; echo $c; })

arr=($(ps whatever | { read a b c d; echo $c $b; }))
echo ${arr[1]}     # will output 'b'`

The Array Solution

So we then end up with the answer by @frayser which is to use the shell variable IFS which defaults to a space, to split the string into an array. It only works in Bash though. Dash and Ash do not support it. I have had a really hard time splitting a string into components in a Busybox thing. It is easy enough to get a single component (e.g. using awk) and then to repeat that for every parameter you need. But then you end up repeatedly calling awk on the same line, or repeatedly using a read block with echo on the same line. Which is not efficient or pretty. So you end up splitting using ${name%% *} and so on. Makes you yearn for some Python skills because in fact shell scripting is not a lot of fun anymore if half or more of the features you are accustomed to, are gone. But you can assume that even python would not be installed on such a system, and it wasn't ;-).

Navigation bar with UIImage for title

let's do try and checkout

let image = UIImage(named: "Navbar_bg.png")
navigationItem.titleView = UIImageView(image: image)
let imageView = UIImageView(frame: CGRect(x: 0, y: 0, width: 40, height: 40))
imageView.contentMode = .ScaleAspectFit

What is the maximum possible length of a query string?

Different web stacks do support different lengths of http-requests. I know from experience that the early stacks of Safari only supported 4000 characters and thus had difficulty handling ASP.net pages because of the USER-STATE. This is even for POST, so you would have to check the browser and see what the stack limit is. I think that you may reach a limit even on newer browsers. I cannot remember but one of them (IE6, I think) had a limit of 16-bit limit, 32,768 or something.

Switch statement equivalent in Windows batch file

I guess all other options would be more cryptic. For those who like readable and non-cryptic code:

IF        "%ID%"=="0" (
    REM do something

) ELSE IF "%ID%"=="1" (
    REM do something else

) ELSE IF "%ID%"=="2" (
    REM do another thing

) ELSE (
    REM default case...
)

It's like an anecdote:

Magician: Put the egg under the hat, do the magic passes ... Remove the hat and ... get the same egg but in the side view ...

The IF ELSE solution isn't that bad. It's almost as good as python's if elif else. More cryptic 'eggs' can be found here.

How to get anchor text/href on click using jQuery?

Updated code

$('a','div.res').click(function(){
  var currentAnchor = $(this);
  alert(currentAnchor.text());
  alert(currentAnchor.attr('href'));
});

Use a list of values to select rows from a pandas dataframe

You can use isin method:

In [1]: df = pd.DataFrame({'A': [5,6,3,4], 'B': [1,2,3,5]})

In [2]: df
Out[2]:
   A  B
0  5  1
1  6  2
2  3  3
3  4  5

In [3]: df[df['A'].isin([3, 6])]
Out[3]:
   A  B
1  6  2
2  3  3

And to get the opposite use ~:

In [4]: df[~df['A'].isin([3, 6])]
Out[4]:
   A  B
0  5  1
3  4  5

How to export SQL Server 2005 query to CSV

You can use following Node.js module to do it with a breeze:

https://www.npmjs.com/package/mssql-to-csv

Programs & Examples On #Concurrentmodification

Why am I not getting a java.util.ConcurrentModificationException in this example?

Why is a ConcurrentModificationException thrown and how to debug it

How do I import a specific version of a package using go get?

bundle install returns "Could not locate Gemfile"

Changing the size of a column referenced by a schema-bound view in SQL Server

Refreshing Web Page By WebDriver When Waiting For Specific Condition

Make content horizontally scroll inside a div

TypeError: $.ajax(...) is not a function?

Appending items to a list of lists in python

How to see docker image contents

How can I use UIColorFromRGB in Swift?

window.open with target "_blank" in Chrome

Reading an Excel file in PHP

How do I get an animated gif to work in WPF?

How to comment out a block of code in Python

Why plt.imshow() doesn't display the image?

AngularJs .$setPristine to reset form

Daylight saving time and time zone best practices

ProcessStartInfo hanging on "WaitForExit"? Why?

How to use ArrayList.addAll()?

How to read a CSV file from a URL with Python?

How to force HTTPS using a web.config file

How to SSH into Docker?

Multiple SQL joins

How to extract file name from path?

Display all dataframe columns in a Jupyter Python Notebook

How to generate unique ID with node.js

How to set the java.library.path from Eclipse

MYSQL Sum Query with IF Condition

Alert handling in Selenium WebDriver (selenium 2) with Java

Android: how to refresh ListView contents?

Finding three elements in an array whose sum is closest to a given number

SQLite in Android How to update a specific row

Change color inside strings.xml

Passing Multiple route params in Angular2

How do you install GLUT and OpenGL in Visual Studio 2012?

Vertical divider CSS

How to delete a folder with files using Java

SQL How to Select the most recent date item

Python reshape list to ndim array

Way to get number of digits in an int?

JavaScript: filter() for Objects

1. Using reduce and Object.keys

2. As (1), in combination with Object.assign

3. Using map and spread syntax instead of reduce

4. Using Object.entries and Object.fromEntries

Converting a list to a set changes element order

Is it possible to run a .NET 4.5 app on XP?

convert a JavaScript string variable to decimal/money

How can I get screen resolution in java?

How to trigger event when a variable's value is changed?

How do I create a crontab through a script

Iterating on a file doesn't work the second time

How to make an ImageView with rounded corners?

How to convert array values to lowercase in PHP?

How to get ID of clicked element with jQuery

How to compare two java objects

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

File upload from <input type="file">

Python "SyntaxError: Non-ASCII character '\xe2' in file"

Get selected item value from Bootstrap DropDown with specific ID

Splitting string into multiple rows in Oracle

Why is String immutable in Java?

Docker official registry (Docker Hub) URL

Creating java date object from year,month,day

How to prevent scientific notation in R?

How to undo 'git reset'?

Hiding table data using <div style="display:none">

Read file content from S3 bucket with boto3

Changing Underline color

What Ruby IDE do you prefer?

Adjust plot title (main) position

Styling a disabled input with css only

Razor View throwing "The name 'model' does not exist in the current context"

CSS Flex Box Layout: full-width row and columns

Android Volley - BasicNetwork.performRequest: Unexpected response code 400

How to add hours to current time in python

What is the best way to get the first letter from a string in Java, returned as a string of length 1?

Calling a Variable from another Class

1. Using `reduce` and `Object.keys`

2. As (1), in combination with `Object.assign`

3. Using `map` and spread syntax instead of `reduce`

4. Using `Object.entries` and `Object.fromEntries`