Programs & Examples On #Variable length array

A variable length array is an array in C99 and other languages whose size is unknown at compile time; instead, it's determined at runtime.

How can I initialize an array without knowing it size?

Here is the code for you`r class . but this also contains lot of refactoring. Please add a for each rather than for. cheers :)

 static int isLeft(ArrayList<String> left, ArrayList<String> right)

    {
        int f = 0;
        for (int i = 0; i < left.size(); i++) {
            for (int j = 0; j < right.size(); j++)

            {
                if (left.get(i).charAt(0) == right.get(j).charAt(0)) {
                    System.out.println("Grammar is left recursive");
                    f = 1;
                }

            }
        }
        return f;

    }

    public static void main(String[] args) {
        // TODO code application logic here
        ArrayList<String> left = new ArrayList<String>();
        ArrayList<String> right = new ArrayList<String>();


        Scanner sc = new Scanner(System.in);
        System.out.println("enter no of prod");
        int n = sc.nextInt();
        for (int i = 0; i < n; i++) {
            System.out.println("enter left prod");
            String leftText = sc.next();
            left.add(leftText);
            System.out.println("enter right prod");
            String rightText = sc.next();
            right.add(rightText);
        }

        System.out.println("the productions are");
        for (int i = 0; i < n; i++) {
            System.out.println(left.get(i) + "->" + right.get(i));
        }
        int flag;
        flag = isLeft(left, right);
        if (flag == 1) {
            System.out.println("Removing left recursion");
        } else {
            System.out.println("No left recursion");
        }

    }

C compile error: "Variable-sized object may not be initialized"

Simply declare length to be a cons, if it is not then you should be allocating memory dynamically

Why aren't variable-length arrays part of the C++ standard?

This was considered for inclusion in C++/1x, but was dropped (this is a correction to what I said earlier).

It would be less useful in C++ anyway since we already have std::vector to fill this role.

How to get files in a relative path in C#

Pretty straight forward, use relative path

string[] offerFiles = Directory.GetFiles(Server.MapPath("~/offers"), "*.csv");

Blur or dim background when Android PopupWindow active

Another trick is to use 2 popup windows instead of one. The 1st popup window will simply be a dummy view with translucent background which provides the dim effect. The 2nd popup window is your intended popup window.

Sequence while creating pop up windows: Show the dummy pop up window 1st and then the intended popup window.

Sequence while destroying: Dismiss the intended pop up window and then the dummy pop up window.

The best way to link these two is to add an OnDismissListener and override the onDismiss() method of the intended to dimiss the dummy popup window from their.

Code for the dummy popup window:

fadepopup.xml

<?xml version="1.0" encoding="utf-8"?>
<LinearLayout xmlns:android="http://schemas.android.com/apk/res/android"
    android:layout_width="match_parent"
    android:layout_height="match_parent"
    android:orientation="vertical" 
    android:id="@+id/fadePopup"
    android:background="#AA000000">
</LinearLayout>

Show fade popup to dim the background

private PopupWindow dimBackground() {

    LayoutInflater inflater = (LayoutInflater) EPGGRIDActivity.this
            .getSystemService(Context.LAYOUT_INFLATER_SERVICE);
    final View layout = inflater.inflate(R.layout.fadepopup,
            (ViewGroup) findViewById(R.id.fadePopup));
    PopupWindow fadePopup = new PopupWindow(layout, windowWidth, windowHeight, false);
    fadePopup.showAtLocation(layout, Gravity.NO_GRAVITY, 0, 0);
    return fadePopup;
}

The server encountered an internal error that prevented it from fulfilling this request - in servlet 3.0

In here:

    if (ValidationUtils.isNullOrEmpty(lastName)) {
        registrationErrors.add(ValidationErrors.LAST_NAME);
    }
    if (!ValidationUtils.isEmailValid(email)) {
        registrationErrors.add(ValidationErrors.EMAIL);
    }

you check for null or empty value on lastname, but in isEmailValid you don't check for empty value. Something like this should do

    if (ValidationUtils.isNullOrEmpty(email) || !ValidationUtils.isEmailValid(email)) {
        registrationErrors.add(ValidationErrors.EMAIL);
    }

or better yet, fix your ValidationUtils.isEmailValid() to cope with null email values. It shouldn't crash, it should just return false.

What is the largest Safe UDP Packet Size on the Internet

I fear i incur upset reactions but nevertheless, to clarify for me if i'm wrong or those seeing this question and being interested in an answer:

my understanding of https://tools.ietf.org/html/rfc1122 whose status is "an official specification" and as such is the reference for the terminology used in this question and which is neither superseded by another RFC nor has errata contradicting the following:

theoretically, ie. based on the written spec., UDP like given by https://tools.ietf.org/html/rfc1122#section-4 has no "packet size". Thus the answer could be "indefinite"

In practice, which is what this questions likely seeked (and which could be updated for current tech in action), this might be different and I don't know.

I apologize if i caused upsetting. https://tools.ietf.org/html/rfc1122#page-8 The "Internet Protocol Suite" and "Architectural Assumptions" don't make clear to me the "assumption" i was on, based on what I heard, that the layers are separate. Ie. the layer UDP is in does not have to concern itself with the layer IP is in (and the IP layer does have things like Reassembly, EMTU_R, Fragmentation and MMS_R (https://tools.ietf.org/html/rfc1122#page-56))

Why is conversion from string constant to 'char*' valid in C but invalid in C++

You can declare like one of the below options:

char data[] = "Testing String";

or

const char* data = "Testing String";

or

char* data = (char*) "Testing String";

AppStore - App status is ready for sale, but not in app store

I had "ready for sale" status for 1 week and app still wasn't visible in store. I "changed" the pricing (from free to free starting today) like KlimczakM suggested in one of comments above. Also, I changed promotional text and saved changes. After less than half of hour app was in the store.

Searching word in vim?

For basic searching:

  • /pattern - search forward for pattern
  • ?pattern - search backward
  • n - repeat forward search
  • N - repeat backward

Some variables you might want to set:

  • :set ignorecase - case insensitive
  • :set smartcase - use case if any caps used
  • :set incsearch - show match as search

Mock MVC - Add Request Parameter to test

@ModelAttribute is a Spring mapping of request parameters to a particular object type. so your parameters might look like userClient.username and userClient.firstName, etc. as MockMvc imitates a request from a browser, you'll need to pass in the parameters that Spring would use from a form to actually build the UserClient object.

(i think of ModelAttribute is kind of helper to construct an object from a bunch of fields that are going to come in from a form, but you may want to do some reading to get a better definition)

How can I find the dimensions of a matrix in Python?

The number of rows of a list of lists would be: len(A) and the number of columns len(A[0]) given that all rows have the same number of columns, i.e. all lists in each index are of the same size.

Enable UTF-8 encoding for JavaScript

just add your script like this:

<script src="/js/intlTelInput.min.js" charset="utf-8"></script>

Duplicate / Copy records in the same MySQL table

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

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

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

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

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

PHP Fatal error: Class 'PDO' not found

you can just find-out loaded config file by executing below command,

 php -i | grep 'php.ini'

Then add below lines to correct php.ini file

extension=pdo.so
extension=pdo_sqlite.so
extension=pdo_mysql.so
extension=sqlite.so

Then restart web server,

service httpd restart

How to combine two strings together in PHP?

No one mentioned this but there is other possibility. I'm using it for huge sql queries. You can use .= operator :)

$string = "the color is ";
$string .= "red";

echo $string; // gives: the color is red

How to get dictionary values as a generic list

Off course, myDico.Values is List<List<MyType>>.

Use Linq if you want to flattern your lists

var items = myDico.SelectMany (d => d.Value).ToList();

Windows equivalent of 'touch' (i.e. the node.js way to create an index.html)

From the Terminal of Visual Code Studio on Windows 10, this is what worked for me to create a new file:

type > hello.js
echo > orange.js
ni > peach.js

Freemarker iterating over hashmap keys

Edit: Don't use this solution with FreeMarker 2.3.25 and up, especially not .get(prop). See other answers.

You use the built-in keys function, e.g. this should work:

<#list user?keys as prop>
    ${prop} = ${user.get(prop)}
</#list>  

How to check for null in a single statement in scala?

Try to avoid using null in Scala. It's really there only for interoperability with Java. In Scala, use Option for things that might be empty. If you're calling a Java API method that might return null, wrap it in an Option immediately.

def getObject : Option[QueueObject] = {
  // Wrap the Java result in an Option (this will become a Some or a None)
  Option(someJavaObject.getResponse)
}

Note: You don't need to put it in a val or use an explicit return statement in Scala; the result will be the value of the last expression in the block (in fact, since there's only one statement, you don't even need a block).

def getObject : Option[QueueObject] = Option(someJavaObject.getResponse)

Besides what the others have already shown (for example calling foreach on the Option, which might be slightly confusing), you could also call map on it (and ignore the result of the map operation if you don't need it):

getObject map QueueManager.add

This will do nothing if the Option is a None, and call QueueManager.add if it is a Some.

I find using a regular if however clearer and simpler than using any of these "tricks" just to avoid an indentation level. You could also just write it on one line:

if (getObject.isDefined) QueueManager.add(getObject.get)

or, if you want to deal with null instead of using Option:

if (getObject != null) QueueManager.add(getObject)

edit - Ben is right, be careful to not call getObject more than once if it has side-effects; better write it like this:

val result = getObject
if (result.isDefined) QueueManager.add(result.get)

or:

val result = getObject
if (result != null) QueueManager.add(result)

How to change date format (MM/DD/YY) to (YYYY-MM-DD) in date picker

Try this:

$.datepicker.parseDate("yy-mm-dd", minValue);

What's the difference between JavaScript and Java?

Here are some differences between the two languages:

  • Java is a statically typed language; JavaScript is dynamic.
  • Java is class-based; JavaScript is prototype-based.
  • Java constructors are special functions that can only be called at object creation; JavaScript "constructors" are just standard functions.
  • Java requires all non-block statements to end with a semicolon; JavaScript inserts semicolons at the ends of certain lines.
  • Java uses block-based scoping; JavaScript uses function-based scoping.
  • Java has an implicit this scope for non-static methods, and implicit class scope; JavaScript has implicit global scope.

Here are some features that I think are particular strengths of JavaScript:

  • JavaScript supports closures; Java can simulate sort-of "closures" using anonymous classes. (Real closures may be supported in a future version of Java.)
  • All JavaScript functions are variadic; Java functions are only variadic if explicitly marked.
  • JavaScript prototypes can be redefined at runtime, and has immediate effect for all referring objects. Java classes cannot be redefined in a way that affects any existing object instances.
  • JavaScript allows methods in an object to be redefined independently of its prototype (think eigenclasses in Ruby, but on steroids); methods in a Java object are tied to its class, and cannot be redefined at runtime.

Rails Object to hash

You could definitely use the attributes to return all attributes but you could add an instance method to Post, call it "to_hash" and have it return the data you would like in a hash. Something like

def to_hash
 { name: self.name, active: true }
end

Python: Binary To Decimal Conversion

You can use int casting which allows the base specification.

int(b, 2)  # Convert a binary string to a decimal int.

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.

JavaScript function in href vs. onclick

This works

<a href="#" id="sampleApp" onclick="myFunction(); return false;">Click Here</a>

Delegation: EventEmitter or Observable in Angular

If one wants to follow a more Reactive oriented style of programming, then definitely the concept of "Everything is a stream" comes into picture and hence, use Observables to deal with these streams as often as possible.

Application.WorksheetFunction.Match method

You are getting this error because the value cannot be found in the range. String or integer doesn't matter. Best thing to do in my experience is to do a check first to see if the value exists.

I used CountIf below, but there is lots of different ways to check existence of a value in a range.

Public Sub test()

Dim rng As Range
Dim aNumber As Long

aNumber = 666

Set rng = Sheet5.Range("B16:B615")

    If Application.WorksheetFunction.CountIf(rng, aNumber) > 0 Then

        rowNum = Application.WorksheetFunction.Match(aNumber, rng, 0)

    Else
        MsgBox aNumber & " does not exist in range " & rng.Address
    End If

End Sub

ALTERNATIVE WAY

Public Sub test()
    Dim rng As Range
    Dim aNumber As Variant
    Dim rowNum As Long

    aNumber = "2gg"

    Set rng = Sheet5.Range("B1:B20")

    If Not IsError(Application.Match(aNumber, rng, 0)) Then
        rowNum = Application.Match(aNumber, rng, 0)
        MsgBox rowNum
    Else
        MsgBox "error"
    End If
End Sub

OR

Public Sub test()
    Dim rng As Range
    Dim aNumber As Variant
    Dim rowNum As Variant

    aNumber = "2gg"

    Set rng = Sheet5.Range("B1:B20")

    rowNum = Application.Match(aNumber, rng, 0)

    If Not IsError(rowNum) Then
        MsgBox rowNum
    Else
        MsgBox "error"
    End If
End Sub

Find maximum value of a column and return the corresponding row values using Pandas

Assuming df has a unique index, this gives the row with the maximum value:

In [34]: df.loc[df['Value'].idxmax()]
Out[34]: 
Country        US
Place      Kansas
Value         894
Name: 7

Note that idxmax returns index labels. So if the DataFrame has duplicates in the index, the label may not uniquely identify the row, so df.loc may return more than one row.

Therefore, if df does not have a unique index, you must make the index unique before proceeding as above. Depending on the DataFrame, sometimes you can use stack or set_index to make the index unique. Or, you can simply reset the index (so the rows become renumbered, starting at 0):

df = df.reset_index()

Can I save input from form to .txt in HTML, using JAVASCRIPT/jQuery, and then use it?

Answer is YES

<html>
<head>
</head>
<body>
<script language="javascript">
function WriteToFile()
{
var fso = new ActiveXObject("Scripting.FileSystemObject");
var s = fso.CreateTextFile("C:\\NewFile.txt", true);
var text=document.getElementById("TextArea1").innerText;
s.WriteLine(text);
s.WriteLine('***********************');
s.Close();
}
</script>

<form name="abc">
<textarea name="text">FIFA</textarea>
<button onclick="WriteToFile()">Click to save</Button>  
</form> 

</body>
</html>

How to generate a random number between a and b in Ruby?

For 10 and 10**24

rand(10**24-10)+10

Android EditText Max Length

I had the same problem.

Here is a workaround

android:inputType="textNoSuggestions|textVisiblePassword"
android:maxLength="6"

Thx to How can I turnoff suggestions in EditText?

Is it possible to import a whole directory in sass using @import?

You can generate SASS file which imports everything automatically, I use this Gulp task:

concatFilenames = require('gulp-concat-filenames')

let concatFilenamesOptions = {
    root: './',
    prepend: "@import '",
    append: "'"
}
gulp.task('sass-import', () => {
    gulp.src(path_src_sass)
        .pipe(concatFilenames('app.sass', concatFilenamesOptions))
        .pipe(gulp.dest('./build'))
})

You can also control importing order by ordering the folders like this:

path_src_sass = [
    './style/**/*.sass', // mixins, variables - import first
    './components/**/*.sass', // singule components
    './pages/**/*.sass' // higher-level templates that could override components settings if necessary
]

Android Studio says "cannot resolve symbol" but project compiles

Change compile to implementation in the build.gradle.

How to SHA1 hash a string in Android?

String.format("%02X%02X%02X%02X%02X%02X%02X%02X%02X%02X%02X%02X%02X%02X%02X%02X%02X%02X%02X%02X", result[0], result[1], result[2], result[3], 
    result[4], result[5], result[6], result[7],
    result[8], result[9], result[10], result[11],
    result[12], result[13], result[14], result[15],
    result[16], result[17], result[18], result[19]);

How to clear the cache of nginx?

I had the exact same problem - I was running my nginx in Virtualbox. I did not have caching turned on. But looks like sendfile was set to on in nginx.conf and that was causing the problem. @kolbyjack mentioned it above in the comments.

When I turned off sendfile - it worked fine.

This is because:

Sendfile is used to ‘copy data between one file descriptor and another‘ and apparently has some real trouble when run in a virtual machine environment, or at least when run through Virtualbox. Turning this config off in nginx causes the static file to be served via a different method and your changes will be reflected immediately and without question

It is related to this bug: https://www.virtualbox.org/ticket/12597

How do I create a link to add an entry to a calendar?

You can have the program create an .ics (iCal) version of the calendar and then you can import this .ics into whichever calendar program you'd like: Google, Outlook, etc.

I know this post is quite old, so I won't bother inputting any code. But please comment on this if you'd like me to provide an outline of how to do this.

Convert json data to a html table

I have rewritten your code in vanilla-js, using DOM methods to prevent html injection.

Demo

_x000D_
_x000D_
var _table_ = document.createElement('table'),_x000D_
  _tr_ = document.createElement('tr'),_x000D_
  _th_ = document.createElement('th'),_x000D_
  _td_ = document.createElement('td');_x000D_
_x000D_
// Builds the HTML Table out of myList json data from Ivy restful service._x000D_
function buildHtmlTable(arr) {_x000D_
  var table = _table_.cloneNode(false),_x000D_
    columns = addAllColumnHeaders(arr, table);_x000D_
  for (var i = 0, maxi = arr.length; i < maxi; ++i) {_x000D_
    var tr = _tr_.cloneNode(false);_x000D_
    for (var j = 0, maxj = columns.length; j < maxj; ++j) {_x000D_
      var td = _td_.cloneNode(false);_x000D_
      cellValue = arr[i][columns[j]];_x000D_
      td.appendChild(document.createTextNode(arr[i][columns[j]] || ''));_x000D_
      tr.appendChild(td);_x000D_
    }_x000D_
    table.appendChild(tr);_x000D_
  }_x000D_
  return table;_x000D_
}_x000D_
_x000D_
// Adds a header row to the table and returns the set of columns._x000D_
// Need to do union of keys from all records as some records may not contain_x000D_
// all records_x000D_
function addAllColumnHeaders(arr, table) {_x000D_
  var columnSet = [],_x000D_
    tr = _tr_.cloneNode(false);_x000D_
  for (var i = 0, l = arr.length; i < l; i++) {_x000D_
    for (var key in arr[i]) {_x000D_
      if (arr[i].hasOwnProperty(key) && columnSet.indexOf(key) === -1) {_x000D_
        columnSet.push(key);_x000D_
        var th = _th_.cloneNode(false);_x000D_
        th.appendChild(document.createTextNode(key));_x000D_
        tr.appendChild(th);_x000D_
      }_x000D_
    }_x000D_
  }_x000D_
  table.appendChild(tr);_x000D_
  return columnSet;_x000D_
}_x000D_
_x000D_
document.body.appendChild(buildHtmlTable([{_x000D_
    "name": "abc",_x000D_
    "age": 50_x000D_
  },_x000D_
  {_x000D_
    "age": "25",_x000D_
    "hobby": "swimming"_x000D_
  },_x000D_
  {_x000D_
    "name": "xyz",_x000D_
    "hobby": "programming"_x000D_
  }_x000D_
]));
_x000D_
_x000D_
_x000D_

Gulp error: The following tasks did not complete: Did you forget to signal async completion?

Here you go: No synchronous tasks.

No synchronous tasks

Synchronous tasks are no longer supported. They often led to subtle mistakes that were hard to debug, like forgetting to return your streams from a task.

When you see the Did you forget to signal async completion? warning, none of the techniques mentioned above were used. You'll need to use the error-first callback or return a stream, promise, event emitter, child process, or observable to resolve the issue.

Using async/await

When not using any of the previous options, you can define your task as an async function, which wraps your task in a promise. This allows you to work with promises synchronously using await and use other synchronous code.

const fs = require('fs');

async function asyncAwaitTask() {
  const { version } = fs.readFileSync('package.json');
  console.log(version);
  await Promise.resolve('some result');
}

exports.default = asyncAwaitTask;

How can I return the difference between two lists?

You may call U.difference(lists) method in underscore-java library. I am the maintainer of the project. Live example

import com.github.underscore.U;
import java.util.Arrays;
import java.util.List;

public class Main {
    public static void main(String[] args) {
        List<Integer> list1 = Arrays.asList(1, 2, 3);
        List<Integer> list2 = Arrays.asList(1, 2);
        List<Integer> list3 = U.difference(list1, list2);
        System.out.println(list3);
        // [3]
    }
}

How to get video duration, dimension and size in PHP?

getID3 supports video formats. See: http://getid3.sourceforge.net/

Edit: So, in code format, that'd be like:

include_once('pathto/getid3.php');
$getID3 = new getID3;
$file = $getID3->analyze($filename);
echo("Duration: ".$file['playtime_string'].
" / Dimensions: ".$file['video']['resolution_x']." wide by ".$file['video']['resolution_y']." tall".
" / Filesize: ".$file['filesize']." bytes<br />");

Note: You must include the getID3 classes before this will work! See the above link.

Edit: If you have the ability to modify the PHP installation on your server, a PHP extension for this purpose is ffmpeg-php. See: http://ffmpeg-php.sourceforge.net/

How to generate and validate a software license key?

It is not possible to prevent software piracy completely. You can prevent casual piracy and that's what all licensing solutions out their do.

Node (machine) locked licensing is best if you want to prevent reuse of license keys. I have been using Cryptlex for about a year now for my software. It has a free plan also, so if you don't expect too many customers you can use it for free.

A Simple AJAX with JSP example

loadXMLDoc JS function should return false, otherwise it will result in postback.

Webpack "OTS parsing error" loading fonts

I know this doesn't answer OPs exact question but I came here with the same symptom but a different cause:

I had the .scss files of Slick Slider included like this:

@import "../../../node_modules/slick-carousel/slick/slick.scss";

On closer inspection it turned out that the it was trying to load the font from an invalid location (<host>/assets/css/fonts/slick.woff), the way it was referenced from the stylesheet.

I ended up simply copying the /font/ to my assets/css/ and the issue was resolved for me.

Comparing the contents of two files in Sublime Text

There are a number of diff plugins available via Package Control. I've used Sublimerge Pro, which worked well enough, but it's a commercial product (with an unlimited trial period) and closed-source, so you can't tweak it if you want to change something, or just look at its internals. FileDiffs is quite popular, judging by the number of installs, so you might want to try that one out.

CSS @font-face not working with Firefox, but working with Chrome and IE

I don't know how you created the syntax as I neved used svg in font declaration, but Font Squirel has a really good tool to create a bullet proof syntax font-face from just one font.

http://www.fontsquirrel.com/fontface/generator

why should I make a copy of a data frame in pandas

This expands on Paul's answer. In Pandas, indexing a DataFrame returns a reference to the initial DataFrame. Thus, changing the subset will change the initial DataFrame. Thus, you'd want to use the copy if you want to make sure the initial DataFrame shouldn't change. Consider the following code:

df = DataFrame({'x': [1,2]})
df_sub = df[0:1]
df_sub.x = -1
print(df)

You'll get:

x
0 -1
1  2

In contrast, the following leaves df unchanged:

df_sub_copy = df[0:1].copy()
df_sub_copy.x = -1

How to install a specific JDK on Mac OS X?

JDK is the Java Development Kit (used to develop Java software).

JRE is the Java Runtime Environment (used to run any .jar file 'Java software').

The JDK contains a JRE inside it.

On Windows when you update Java, it updates the JRE automatically.

On Mac you do not have a JRE separated you have it, but inside the JDK, so when you update Java it will update your JRE which is inside your JDK; it doesn't install an JDK for you. You need to get it from somewhere else.

How to Set OnClick attribute with value containing function in ie8?

You could also set onclick to call your function like this:

foo.onclick = function() { callYourJSFunction(arg1, arg2); };

This way, you can pass arguments too. .....

C# Convert a Base64 -> byte[]

You have to use Convert.FromBase64String to turn a Base64 encoded string into a byte[].

How to fix warning from date() in PHP"

error_reporting(E_ALL ^ E_WARNING);

:)

You should change subject to "How to fix warning from date() in PHP"...

How to show Alert Message like "successfully Inserted" after inserting to DB using ASp.net MVC3

Personally I'd go with AJAX.

If you cannot switch to @Ajax... helpers, I suggest you to add a couple of properties in your model

public bool TriggerOnLoad { get; set; }
public string TriggerOnLoadMessage { get; set: }

Change your view to a strongly typed Model via

@using MyModel

Before returning the View, in case of successfull creation do something like

MyModel model = new MyModel();
model.TriggerOnLoad = true;
model.TriggerOnLoadMessage = "Object successfully created!";
return View ("Add", model);

then in your view, add this

@{
   if (model.TriggerOnLoad) {
   <text>
   <script type="text/javascript">
     alert('@Model.TriggerOnLoadMessage');
   </script>
   </text>
   }
}

Of course inside the tag you can choose to do anything you want, event declare a jQuery ready function:

$(document).ready(function () {
   alert('@Model.TriggerOnLoadMessage');
});

Please remember to reset the Model properties upon successfully alert emission.

Another nice thing about MVC is that you can actually define an EditorTemplate for all this, and then use it in your view via:

@Html.EditorFor (m => m.TriggerOnLoadMessage)

But in case you want to build up such a thing, maybe it's better to define your own C# class:

class ClientMessageNotification {
    public bool TriggerOnLoad { get; set; }
    public string TriggerOnLoadMessage { get; set: }
}

and add a ClientMessageNotification property in your model. Then write EditorTemplate / DisplayTemplate for the ClientMessageNotification class and you're done. Nice, clean, and reusable.

How to disable and then enable onclick event on <div> with javascript

I'm confused by your question, seems to me that the question title and body are asking different things. If you want to disable/enable a click event on a div simply do:

$("#id").on('click', function(){ //enables click event
    //do your thing here
});

$("#id").off('click'); //disables click event

If you want to disable a div, use the following code:

$("#id").attr('disabled','disabled');

Hope this helps.

edit: oops, didn't see the other bind/unbind answer. Sorry. Those methods are also correct, though they've been deprecated in jQuery 1.7, and replaced by on()/off()

SQL statement to get column type

Another variation using MS SQL:

SELECT TYPE_NAME(system_type_id) 
FROM sys.columns 
WHERE name = 'column_name'
AND [object_id] = OBJECT_ID('[dbo].[table_name]');

How can I combine multiple nested Substitute functions in Excel?

I would use the following approach:

=SUBSTITUTE(LEFT(A2,LEN(A2)-X),"_","-")

where X denotes the length of things you're not after. And, for X I'd use

(ISERROR(FIND("_S",A2,1))*2)+
(ISERROR(FIND("_40K",A2,1))*4)+
(ISERROR(FIND("_60K",A2,1))*4)+
(ISERROR(FIND("_AB",A2,1))*3)+
(ISERROR(FIND("_CD",A2,1))*3)+
(ISERROR(FIND("_EF",A2,1))*3)

The above ISERROR(FIND("X",.,.))*x will return 0 if X is not found and x (the length of X) if it is found. So technically you're trimming A2 from the right with possible matches.

The advantage of this approach above the other mentioned is that it's more apparent what substitution (or removal) is taking place, since the "substitution" is not nested.

Iterating over JSON object in C#

dynamic dynJson = JsonConvert.DeserializeObject(json);
foreach (var item in dynJson)
{
    Console.WriteLine("{0} {1} {2} {3}\n", item.id, item.displayName, 
        item.slug, item.imageUrl);
}

or

var list = JsonConvert.DeserializeObject<List<MyItem>>(json);

public class MyItem
{
    public string id;
    public string displayName;
    public string name;
    public string slug;
    public string imageUrl;
}

How to check if one DateTime is greater than the other in C#

I'd like to demonstrate that if you convert to .Date that you don't need to worry about hours/mins/seconds etc:

    [Test]
    public void ConvertToDateWillHaveTwoDatesEqual()
    {
        DateTime d1 = new DateTime(2008, 1, 1);
        DateTime d2 = new DateTime(2008, 1, 2);
        Assert.IsTrue(d1 < d2);

        DateTime d3 = new DateTime(2008, 1, 1,7,0,0);
        DateTime d4 = new DateTime(2008, 1, 1,10,0,0);
        Assert.IsTrue(d3 < d4);
        Assert.IsFalse(d3.Date < d4.Date);
    }

Google maps API V3 method fitBounds()

 var map = new google.maps.Map(document.getElementById("map"),{
                mapTypeId: google.maps.MapTypeId.ROADMAP

            });
var bounds = new google.maps.LatLngBounds();

for (i = 0; i < locations.length; i++){
        marker = new google.maps.Marker({
            position: new google.maps.LatLng(locations[i][1], locations[i][2]),
            map: map
        });
bounds.extend(marker.position);
}
map.fitBounds(bounds);

Dynamically updating plot in matplotlib

Here is a way which allows to remove points after a certain number of points plotted:

import matplotlib.pyplot as plt
# generate axes object
ax = plt.axes()

# set limits
plt.xlim(0,10) 
plt.ylim(0,10)

for i in range(10):        
     # add something to axes    
     ax.scatter([i], [i]) 
     ax.plot([i], [i+1], 'rx')

     # draw the plot
     plt.draw() 
     plt.pause(0.01) #is necessary for the plot to update for some reason

     # start removing points if you don't want all shown
     if i>2:
         ax.lines[0].remove()
         ax.collections[0].remove()

How do I make a transparent border with CSS?

Yep, you can use border: 1px solid transparent

Another solution is to use outline on hover (and set the border to 0) which doesn't affect the document flow:

li{
    display:inline-block;
    padding:5px;
    border:0;
}
li:hover{
    outline:1px solid #FC0;
}

NB. You can only set the outline as a sharthand property, not for individual sides. It's only meant to be used for debugging but it works nicely.

Easy way of running the same junit test over and over?

You could run your JUnit test from a main method and repeat it so many times you need:

package tests;

import static org.junit.Assert.*;

import org.junit.Test;
import org.junit.runner.Result;

public class RepeatedTest {

    @Test
    public void test() {
        fail("Not yet implemented");
    }

    public static void main(String args[]) {

        boolean runForever = true;

        while (runForever) {
            Result result = org.junit.runner.JUnitCore.runClasses(RepeatedTest.class);

            if (result.getFailureCount() > 0) {
                runForever = false;
               //Do something with the result object

            }
        }

    }

}

how to insert a new line character in a string to PrintStream then use a scanner to re-read the file

The linefeed character \n is not the line separator in certain operating systems (such as windows, where it's "\r\n") - my suggestion is that you use \r\n instead, then it'll both see the line-break with only \n and \r\n, I've never had any problems using it.

Also, you should look into using a StringBuilder instead of concatenating the String in the while-loop at BookCatalog.toString(), it is a lot more effective. For instance:

public String toString() {
        BookNode current = front;
        StringBuilder sb = new StringBuilder();
        while (current!=null){
            sb.append(current.getData().toString()+"\r\n ");
            current = current.getNext();
        }
        return sb.toString();
}

How do I center content in a div using CSS?

By using transform: works like a charm!

<div class="parent">
    <span>center content using transform</span>
    </div>

    //CSS
    .parent {
        position: relative;
        height: 200px;
        border: 1px solid;
    }
    .parent span {
        position: absolute;
        top: 50%;
        left: 50%;
        -webkit-transform: translate(-50%, -50%);
        transform: translate(-50%, -50%);
    }

How do I display the current value of an Android Preference in the Preference summary?

public class ProfileManagement extends PreferenceActivity implements
OnPreferenceChangeListener {
    EditTextPreference screenName;
    ListPreference sex;

    @Override
    protected void onCreate(Bundle savedInstanceState) {
            super.onCreate(savedInstanceState);
            addPreferencesFromResource(R.layout.profile_management);

            screenName = (EditTextPreference) findPreference("editTextPref");
            sex = (ListPreference) findPreference("sexSelector");

            screenName.setOnPreferenceChangeListener(this);
            sex.setOnPreferenceChangeListener(this);

    }   

    @Override
    public boolean onPreferenceChange(Preference preference, Object newValue) {
        preference.setSummary(newValue.toString());
        return true;
    }
}

How do I seed a random class to avoid getting duplicate random values

this workes for me:

private int GetaRandom()
    {
        Thread.Sleep(1);
        return new Random(DateTime.Now.Millisecond).Next();
    }

Advantages of SQL Server 2008 over SQL Server 2005?

  • Transparent Data Encryption. The ability to encrypt an entire database.
  • Backup Encryption. Executed at backup time to prevent tampering.
  • External Key Management. Storing Keys separate from the data.
  • Auditing. Monitoring of data access.
  • Data Compression. Fact Table size reduction and improved performance.
  • Resource Governor. Restrict users or groups from consuming high levels or resources.
  • Hot Plug CPU. Add CPUs on the fly.
  • Performance Studio. Collection of performance monitoring tools.
  • Installation improvements. Disk images and service pack uninstall options.
  • Dynamic Development. New ADO and Visual Studio options as well as Dot Net 3.
  • Entity Data Services. Line Of Business (LOB) framework and Entity Query Language (eSQL)
  • LINQ. Development query language for access multiple types of data such as SQL and XML.
  • Data Synchronizing. Development of frequently disconnected applications.
  • Large UDT. No size restriction on UDT.
  • Dates and Times. New data types: Date, Time, Date Time Offset.
  • File Stream. New data type VarBinary(Max) FileStream for managing binary data.
  • Table Value Parameters. The ability to pass an entire table to a stored procedure.
  • Spatial Data. Data type for storing Latitude, Longitude, and GPS entries.
  • Full Text Search. Native Indexes, thesaurus as metadata, and backup ability.
  • SQL Server Integration Service. Improved multiprocessor support and faster lookups.
  • MERGE. TSQL command combining Insert, Update, and Delete.
  • SQL Server Analysis Server. Stack improvements, faster block computations.
  • SQL Server Reporting Server. Improved memory management and better rendering.
  • Microsoft Office 2007. Use OFFICE as an SSRS template. SSRS to WORD.
  • SQL 2000 Support Ends. Mainstream Support for SQL 2000 is coming to an end.

(Good intro article part 1, part 2, part 3. As for compelling reasons, that depends on what you are using SQL server for. Do you need hierarchical data types? Do you currently store files in the database and want to switch over to SQL Server's new filestream feature? Could you use more disk space by turning on data compression?

And let's not forget the ability to MERGE data.

Tomcat 8 Maven Plugin for Java 8

Plugin run Tomcat 7.0.47:

mvn org.apache.tomcat.maven:tomcat7-maven-plugin:2.2:run

 ...
 INFO: Starting Servlet Engine: Apache Tomcat/7.0.47

This is sample to run plugin with Tomcat 8 and Java 8: Cargo embedded tomcat: custom context.xml

How do I remove a comma off the end of a string?

This is a classic question, with two solutions. If you want to remove exactly one comma, which may or may not be there, use:

if (substr($string, -1, 1) == ',')
{
  $string = substr($string, 0, -1);
}

If you want to remove all commas from the end of a line use the simpler:

$string = rtrim($string, ',');

The rtrim function (and corresponding ltrim for left trim) is very useful as you can specify a range of characters to remove, i.e. to remove commas and trailing whitespace you would write:

$string = rtrim($string, ", \t\n");

What is the difference between onBlur and onChange attribute in HTML?

onBlur is when your focus is no longer on the field in question.

The onblur property returns the onBlur event handler code, if any, that exists on the current element.

onChange is when the value of the field changes.

Get and Set a Single Cookie with Node.js HTTP Server

Cookies are transfered through HTTP-Headers
You'll only have to parse the request-headers and put response-headers.

How can I use Google's Roboto font on a website?

For Website you can use 'Roboto' font as below:

If you have created separate css file then put below line at the top of css file as:

@import url('https://fonts.googleapis.com/css?family=Roboto:300,300i,400,400i,500,500i,700,700i,900,900i');

Or if you don't want to create separate file then add above line in between <style>...</style>:

<style>
  @import url('https://fonts.googleapis.com/css? 
  family=Roboto:300,300i,400,400i,500,500i,700,700i,900,900i');
</style>

then:

html, body {
    font-family: 'Roboto', sans-serif;
}

What is the difference between spark.sql.shuffle.partitions and spark.default.parallelism?

From the answer here, spark.sql.shuffle.partitions configures the number of partitions that are used when shuffling data for joins or aggregations.

spark.default.parallelism is the default number of partitions in RDDs returned by transformations like join, reduceByKey, and parallelize when not set explicitly by the user. Note that spark.default.parallelism seems to only be working for raw RDD and is ignored when working with dataframes.

If the task you are performing is not a join or aggregation and you are working with dataframes then setting these will not have any effect. You could, however, set the number of partitions yourself by calling df.repartition(numOfPartitions) (don't forget to assign it to a new val) in your code.


To change the settings in your code you can simply do:

sqlContext.setConf("spark.sql.shuffle.partitions", "300")
sqlContext.setConf("spark.default.parallelism", "300")

Alternatively, you can make the change when submitting the job to a cluster with spark-submit:

./bin/spark-submit --conf spark.sql.shuffle.partitions=300 --conf spark.default.parallelism=300

Wait until flag=true

using non blocking javascript with EventTarget API

In my example, i need to wait for a callback before to use it. I have no idea when this callback is set. It can be before of after i need to execute it. And i can need to call it several time (everything async)

_x000D_
_x000D_
// bus to pass event_x000D_
const bus = new EventTarget();_x000D_
_x000D_
// it's magic_x000D_
const waitForCallback = new Promise((resolve, reject) => {_x000D_
    bus.addEventListener("initialized", (event) => {_x000D_
        resolve(event.detail);_x000D_
    });_x000D_
});_x000D_
_x000D_
_x000D_
_x000D_
// LET'S TEST IT !_x000D_
_x000D_
_x000D_
// launch before callback has been set_x000D_
waitForCallback.then((callback) => {_x000D_
    console.log(callback("world"));_x000D_
});_x000D_
_x000D_
_x000D_
// async init_x000D_
setTimeout(() => {_x000D_
    const callback = (param) => { return `hello ${param.toString()}`; }_x000D_
    bus.dispatchEvent(new CustomEvent("initialized", {detail: callback}));_x000D_
}, 500);_x000D_
_x000D_
_x000D_
// launch after callback has been set_x000D_
setTimeout(() => {_x000D_
    waitForCallback.then((callback) => {_x000D_
        console.log(callback("my little pony"));_x000D_
    });_x000D_
}, 1000);
_x000D_
_x000D_
_x000D_

Split output of command by columns using Bash?

Getting the correct line (example for line no. 6) is done with head and tail and the correct word (word no. 4) can be captured with awk:

command|head -n 6|tail -n 1|awk '{print $4}'

How do you get the list of targets in a makefile?

If you have bash completion for make installed, the completion script will define a function _make_target_extract_script. This function is meant to create a sed script which can be used to obtain the targets as a list.

Use it like this:

# Make sure bash completion is enabled
source /etc/bash_completion 

# List targets from Makefile
sed -nrf <(_make_target_extract_script --) Makefile

Authenticate with GitHub using a token

I'm on Ubuntu 20.04 and I kept getting the message that soon I wouldn't be able to login from console. I was terribly confused. Finally, I got to the URL below which will work. But you need to know how to create a PAT (Personal Access Token) which you are going to have to keep in a file on your computer.

Here's what the final URL will look like:

git push https://[email protected]/user-name/repo.git

long PAT (Personal Access Token) value -- The entire long value between the // and the @ sign in the url is your PAT.

user-name will be your exact username

repo.git will be your exact repo name

You need to generate a PAT following the steps at: https://docs.github.com/en/github/authenticating-to-github/creating-a-personal-access-token

That will give you the PAT value that you will place in your URL.

When you create the PAT make sure you choose the following options so it has the ability to allow you to manage your REPOs. PAT settings

Save Your PAT Or Lose It

Once you have your PAT. You're going to need to save it in a file locally so you can use it again. If you don't save it somewhere there is no way to ever see it again and you'll be forced to create a new PAT

Now you're going to need at the very least :

  1. a way to display it in your console so you can see it again.
  2. or, A way to copy it to your clipboard automatically.

For 1, just use :

$ cat ~/files/myPatFile.txt

Where the path is a real path to the location and file where you stored your PAT value.

For 2

$ xclip -selection clipboard < ~/files/myPatFile.txt

That'll copy the contents of the file to the clipboard so you can use your PAT more easily.

FYI - if you don't have xclip do the following:

$ sudo apt-get install xclip

Downloads and installs xclip. If you don't have apt-get, you might need to use another installer (like yum)

PDOException SQLSTATE[HY000] [2002] No such file or directory

Check your port carefully . In my case it was 8889 and i am using 8888. change "DB_HOST" from "localhost" to "127.0.0.1" and vice versa

How do you change the launcher logo of an app in Android Studio?

Here are my steps for the task:

  1. Create PNG image file of size 512x512 pixels
  2. In Android Studio, in project view, highlight a mipmap directory
  3. In menu, go to File>New>Image Asset
  4. Click Image Button in Asset type button row
  5. Click on 3 Dot Box at right of Path Box.
  6. Drag image to source asset box
  7. Click Next (Note: Existing launcher files will be overwritten)
  8. Click Finish

WooCommerce - get category for product page

I literally striped out this line of code from content-single-popup.php located in woocommerce folder in my theme directory.

global $product; 
echo $product->get_categories( ', ', ' ' . _n( ' ', '  ', $cat_count, 'woocommerce' ) . ' ', ' ' );

Since my theme that I am working on has integrated woocommerce in it, this was my solution.

JSON.net: how to deserialize without using the default constructor?

Solution:

public Response Get(string jsonData) {
    var json = JsonConvert.DeserializeObject<modelname>(jsonData);
    var data = StoredProcedure.procedureName(json.Parameter, json.Parameter, json.Parameter, json.Parameter);
    return data;
}

Model:

public class modelname {
    public long parameter{ get; set; }
    public int parameter{ get; set; }
    public int parameter{ get; set; }
    public string parameter{ get; set; }
}

Open File in Another Directory (Python)

import os
import os.path
import shutil

You find your current directory:

d = os.getcwd() #Gets the current working directory

Then you change one directory up:

os.chdir("..") #Go up one directory from working directory

Then you can get a tupple/list of all the directories, for one directory up:

o = [os.path.join(d,o) for o in os.listdir(d) if os.path.isdir(os.path.join(d,o))] # Gets all directories in the folder as a tuple

Then you can search the tuple for the directory you want and open the file in that directory:

for item in o:
    if os.path.exists(item + '\\testfile.txt'):
    file = item + '\\testfile.txt'

Then you can do stuf with the full file path 'file'

How to get build time stamp from Jenkins build variables?

Try use Build Timestamp Plugin and use BUILD_TIMESTAMP variable.

How to check if a date is in a given range?

Convert both dates to timestamps then do

pseudocode:

if date_from_user > start_date && date_from_user < end_date
    return true

Adding css class through aspx code behind

If you're not using the id for anything other than code-behind reference (since .net mangles the ids), you could use a panel control and reference it in your codebehind:

<asp:panel runat="server" id="classMe"></asp:panel>

classMe.cssClass = "someClass"

How to solve '...is a 'type', which is not valid in the given context'? (C#)

CERAS is a class name which cannot be assigned. As the class implements IDisposable a typical usage would be:

using (CERas.CERAS ceras = new CERas.CERAS())
{
    // call some method on ceras
}

How to fix "Your Ruby version is 2.3.0, but your Gemfile specified 2.2.5" while server starting

Your Gemfile has a line reading

ruby '2.2.5'

Change it to

ruby '2.3.0'

Then run

bundle install

What is a NullReferenceException, and how do I fix it?

You can fix NullReferenceException in a clean way using Null-conditional Operators in c#6 and write less code to handle null checks.

It's used to test for null before performing a member access (?.) or index (?[) operation.

Example

  var name = p?.Spouse?.FirstName;

is equivalent to:

    if (p != null)
    {
        if (p.Spouse != null)
        {
            name = p.Spouse.FirstName;
        }
    }

The result is that the name will be null when p is null or when p.Spouse is null.

Otherwise, the variable name will be assigned the value of the p.Spouse.FirstName.

For More details : Null-conditional Operators

Jaxb, Class has two properties of the same name

just added this to my class

@XmlAccessorType(XmlAccessType.FIELD)

worked like a cham

Using Address Instead Of Longitude And Latitude With Google Maps API

You can parse the geolocation through the addresses. Create an Array with jquery like this:

//follow this structure
var addressesArray = [
  'Address Str.No, Postal Area/city'
]

//loop all the addresses and call a marker for each one
for (var x = 0; x < addressesArray.length; x++) {
  $.getJSON('http://maps.googleapis.com/maps/api/geocode/json?address='+addressesArray[x]+'&sensor=false', null, function (data) {
    var p = data.results[0].geometry.location
    var latlng = new google.maps.LatLng(p.lat, p.lng);
    //it will place marker based on the addresses, which they will be translated as geolocations.
    var aMarker= new google.maps.Marker({
      position: latlng,
      map: map
    });
  });
}

Also please note that Google limit your results if you don't have a business account with them, and you my get an error if you use too many addresses.

Online PHP syntax checker / validator

In case you're interested, an offline checker that does complicated type analysis: http://strongphp.org It is not online however.

How can I use "e" (Euler's number) and power operation in python 2.7

You can use exp(x) function of math library, which is same as e^x. Hence you may write your code as:

import math
x.append(1 - math.exp( -0.5 * (value1*value2)**2))

I have modified the equation by replacing 1/2 as 0.5. Else for Python <2.7, we'll have to explicitly type cast the division value to float because Python round of the result of division of two int as integer. For example: 1/2 gives 0 in python 2.7 and below.

C# "must declare a body because it is not marked abstract, extern, or partial"

You can just use the keywork value to accomplish this.

public int Hour {
    get{
        // Do some logic if you want
        //return some custom stuff based on logic

        // or just return the value
        return value;
    }; set { 
        // Do some logic stuff 
        if(value < MINVALUE){
            this.Hour = 0;
        } else {
            // Or just set the value
            this.Hour = value;
        }
    }
}

jquery: get elements by class name and add css to each of them

What makes jQuery easy to use is that you don't have to apply attributes to each element. The jQuery object contains an array of elements, and the methods of the jQuery object applies the same attributes to all the elements in the array.

There is also a shorter form for $(document).ready(function(){...}) in $(function(){...}).

So, this is all you need:

$(function(){
  $('div.easy_editor').css('border','9px solid red');
});

If you want the code to work for any element with that class, you can just specify the class in the selector without the tag name:

$(function(){
  $('.easy_editor').css('border','9px solid red');
});

Display label text with line breaks in c#

I know this thread is old, but...

If you're using html encoding (like AntiXSS), the previous answers will not work. The break tags will be rendered as text, rather than applying a carriage return. You can wrap your asp label in a pre tag, and it will display with whatever line breaks are set from the code behind.

Example:

<pre style="width:600px;white-space:pre-wrap;"><asp:Label ID="lblMessage" Runat="server" visible ="true"/></pre>

jQuery form validation on button click

You can also achieve other way using button tag

According new html5 attribute you also can add a form attribute like

<form id="formId">
    <input type="text" name="fname">
</form>

<button id="myButton" form='#formId'>My Awesome Button</button>

So the button will be attached to the form.

This should work with the validate() plugin of jQuery like :

var validator = $( "#formId" ).validate();
validator.element( "#myButton" );

It's working too with input tag

Source :

https://developer.mozilla.org/docs/Web/HTML/Element/Button

JUnit 5: How to assert an exception is thrown?

Now Junit5 provides a way to assert the exceptions

You can test both general exceptions and customized exceptions

A general exception scenario:

ExpectGeneralException.java

public void validateParameters(Integer param ) {
    if (param == null) {
        throw new NullPointerException("Null parameters are not allowed");
    }
}

ExpectGeneralExceptionTest.java

@Test
@DisplayName("Test assert NullPointerException")
void testGeneralException(TestInfo testInfo) {
    final ExpectGeneralException generalEx = new ExpectGeneralException();

     NullPointerException exception = assertThrows(NullPointerException.class, () -> {
            generalEx.validateParameters(null);
        });
    assertEquals("Null parameters are not allowed", exception.getMessage());
}

You can find a sample to test CustomException here : assert exception code sample

ExpectCustomException.java

public String constructErrorMessage(String... args) throws InvalidParameterCountException {
    if(args.length!=3) {
        throw new InvalidParameterCountException("Invalid parametercount: expected=3, passed="+args.length);
    }else {
        String message = "";
        for(String arg: args) {
            message += arg;
        }
        return message;
    }
}

ExpectCustomExceptionTest.java

@Test
@DisplayName("Test assert exception")
void testCustomException(TestInfo testInfo) {
    final ExpectCustomException expectEx = new ExpectCustomException();

     InvalidParameterCountException exception = assertThrows(InvalidParameterCountException.class, () -> {
            expectEx.constructErrorMessage("sample ","error");
        });
    assertEquals("Invalid parametercount: expected=3, passed=2", exception.getMessage());
}

Get elements by attribute when querySelectorAll is not available without using libraries?

Use

//find first element with "someAttr" attribute
document.querySelector('[someAttr]')

or

//find all elements with "someAttr" attribute
document.querySelectorAll('[someAttr]') 

to find elements by attribute. It's now supported in all relevant browsers (even IE8): http://caniuse.com/#search=queryselector

The pipe ' ' could not be found angular2 custom pipe

Make sure you are not facing a "cross module" problem

If the component which is using the pipe, doesn't belong to the module which has declared the pipe component "globally" then the pipe is not found and you get this error message.

In my case I've declared the pipe in a separate module and imported this pipe module in any other module having components using the pipe.

I have declared a that the component in which you are using the pipe is

the Pipe Module

 import { NgModule }      from '@angular/core';
 import { myDateFormat }          from '../directives/myDateFormat';

 @NgModule({
     imports:        [],
     declarations:   [myDateFormat],
     exports:        [myDateFormat],
 })

 export class PipeModule {

   static forRoot() {
      return {
          ngModule: PipeModule,
          providers: [],
      };
   }
 } 

Usage in another module (e.g. app.module)

  // Import APPLICATION MODULES
  ...
  import { PipeModule }    from './tools/PipeModule';

  @NgModule({
     imports: [
    ...
    , PipeModule.forRoot()
    ....
  ],

Setting the User-Agent header for a WebClient request

You can also use that:

client.Headers.Add(HttpRequestHeader.UserAgent, "My app.");

What's the difference between `raw_input()` and `input()` in Python 3?

Python 2:

  • raw_input() takes exactly what the user typed and passes it back as a string.

  • input() first takes the raw_input() and then performs an eval() on it as well.

The main difference is that input() expects a syntactically correct python statement where raw_input() does not.

Python 3:

  • raw_input() was renamed to input() so now input() returns the exact string.
  • Old input() was removed.

If you want to use the old input(), meaning you need to evaluate a user input as a python statement, you have to do it manually by using eval(input()).

Getting a list of files in a directory with a glob

Very Simplest Method:

NSArray *paths = NSSearchPathForDirectoriesInDomains(NSDocumentDirectory, 
                                                     NSUserDomainMask, YES);
NSString *documentsDirectory = [paths objectAtIndex:0];

NSFileManager *manager = [NSFileManager defaultManager];
NSArray *fileList = [manager contentsOfDirectoryAtPath:documentsDirectory 
                                                 error:nil];
//--- Listing file by name sort
NSLog(@"\n File list %@",fileList);

//---- Sorting files by extension    
NSArray *filePathsArray = 
  [[NSFileManager defaultManager] subpathsOfDirectoryAtPath:documentsDirectory  
                                                      error:nil];
NSPredicate *predicate = [NSPredicate predicateWithFormat:@"SELF EndsWith '.png'"];
filePathsArray =  [filePathsArray filteredArrayUsingPredicate:predicate];
NSLog(@"\n\n Sorted files by extension %@",filePathsArray);

How do I use WPF bindings with RelativeSource?

If you want to bind to another property on the object:

{Binding Path=PathToProperty, RelativeSource={RelativeSource Self}}

If you want to get a property on an ancestor:

{Binding Path=PathToProperty,
    RelativeSource={RelativeSource AncestorType={x:Type typeOfAncestor}}}

If you want to get a property on the templated parent (so you can do 2 way bindings in a ControlTemplate)

{Binding Path=PathToProperty, RelativeSource={RelativeSource TemplatedParent}}

or, shorter (this only works for OneWay bindings):

{TemplateBinding Path=PathToProperty}

Meaning of end='' in the statement print("\t",end='')?

See the documentation for the print function: print()

The content of end is printed after the thing you want to print. By default it contains a newline ("\n") but it can be changed to something else, like an empty string.

How do I get unique elements in this array?

Have you looked at this page?

http://www.mongodb.org/display/DOCS/Aggregation#Aggregation-Distinct

That might save you some time?

eg db.addresses.distinct("zip-code");

Read and write into a file using VBScript

You could also read the entire file in, and store it in an array

Set filestreamIN = CreateObject("Scripting.FileSystemObject").OpenTextFile("C:\Test.txt",1)
file = Split(filestreamIN.ReadAll(), vbCrLf)
filestreamIN.Close()
Set filestreamIN = Nothing

Manipulate the array in any way you choose, and then write the array back to the file.

Set filestreamOUT = CreateObject("Scripting.FileSystemObject").OpenTextFile("C:\Test.txt",2,true)

for i = LBound(file) to UBound(file)
    filestreamOUT.WriteLine(file(i))
Next

filestreamOUT.Close()
Set filestreamOUT = Nothing 

make an html svg object also a clickable link

A simplification of Richard's solution. Works at least in Firefox, Safari and Opera:

<a href="..." style="display: block;">
    <object data="..." style="pointer-events: none;" />
</a>

See http://www.noupe.com/tutorial/svg-clickable-71346.html for additional solutions.

Mockito: Trying to spy on method is calling the original method

In my case, using Mockito 2.0, I had to change all the any() parameters to nullable() in order to stub the real call.

Convert ArrayList to String array in Android

String[] array = new String[items2.size()];
items2.toArray(array);

How can I join multiple SQL tables using the IDs?

SELECT 
    a.nameA, /* TableA.nameA */
    d.nameD /* TableD.nameD */
FROM TableA a 
    INNER JOIN TableB b on b.aID = a.aID 
    INNER JOIN TableC c on c.cID = b.cID 
    INNER JOIN TableD d on d.dID = a.dID 
WHERE DATE(c.`date`) = CURDATE()

How do I add a tool tip to a span element?

In most browsers, the title attribute will render as a tooltip, and is generally flexible as to what sorts of elements it'll work with.

<span title="This will show as a tooltip">Mouse over for a tooltip!</span>
<a href="http://www.stackoverflow.com" title="Link to stackoverflow.com">stackoverflow.com</a>
<img src="something.png" alt="Something" title="Something">

All of those will render tooltips in most every browser.

Why does the Google Play store say my Android app is incompatible with my own device?

I had the same problem. It was caused by having different version codes and numbers in my manifest and gradle build script. I resolved it by removing the version code and version number from my manifest and letting gradle take care of it.

Parsing json and searching through it

As json.loads simply returns a dict, you can use the operators that apply to dicts:

>>> jdata = json.load('{"uri": "http:", "foo", "bar"}')
>>> 'uri' in jdata       # Check if 'uri' is in jdata's keys
True
>>> jdata['uri']         # Will return the value belonging to the key 'uri'
u'http:'

Edit: to give an idea regarding how to loop through the data, consider the following example:

>>> import json
>>> jdata = json.loads(open ('bookmarks.json').read())
>>> for c in jdata['children'][0]['children']:
...     print 'Title: {}, URI: {}'.format(c.get('title', 'No title'),
                                          c.get('uri', 'No uri'))
...
Title: Recently Bookmarked, URI: place:folder=BOOKMARKS_MENU(...)
Title: Recent Tags, URI: place:sort=14&type=6&maxResults=10&queryType=1
Title: , URI: No uri
Title: Mozilla Firefox, URI: No uri

Inspecting the jdata data structure will allow you to navigate it as you wish. The pprint call you already have is a good starting point for this.

Edit2: Another attempt. This gets the file you mentioned in a list of dictionaries. With this, I think you should be able to adapt it to your needs.

>>> def build_structure(data, d=[]):
...     if 'children' in data:
...         for c in data['children']:
...             d.append({'title': c.get('title', 'No title'),
...                                      'uri': c.get('uri', None)})
...             build_structure(c, d)
...     return d
...
>>> pprint.pprint(build_structure(jdata))
[{'title': u'Bookmarks Menu', 'uri': None},
 {'title': u'Recently Bookmarked',
  'uri':   u'place:folder=BOOKMARKS_MENU&folder=UNFILED_BOOKMARKS&(...)'},
 {'title': u'Recent Tags',
  'uri':   u'place:sort=14&type=6&maxResults=10&queryType=1'},
 {'title': u'', 'uri': None},
 {'title': u'Mozilla Firefox', 'uri': None},
 {'title': u'Help and Tutorials',
  'uri':   u'http://www.mozilla.com/en-US/firefox/help/'},
 (...)
}]

To then "search through it for u'uri': u'http:'", do something like this:

for c in build_structure(jdata):
    if c['uri'].startswith('http:'):
        print 'Started with http'

PHP new line break in emails

I know this is an old question but anyway it might help someone.

I tend to use PHP_EOL for this purposes (due to cross-platform compatibility).

echo "line 1".PHP_EOL."line 2".PHP_EOL;

If you're planning to show the result in a browser then you have to use "<br>".

EDIT: since your exact question is about emails, things are a bit different. For pure text emails see Brendan Bullen's accepted answer. For HTML emails you simply use HTML formatting.

Determine the path of the executing BASH script

echo Running from `dirname $0`

Android: How to stretch an image to the screen width while maintaining aspect ratio?

ScaleType.CENTER_CROP will do what you want: stretch to full width, and scale the height accordingly. if the scaled height exceeds the screen limits, the image will be cropped.

JUNIT testing void methods

If your method has no side effects, and doesn't return anything, then it's not doing anything.

If your method does some computation and returns the result of that computation, you can obviously enough assert that the result returned is correct.

If your code doesn't return anything but does have side effects, you can call the code and then assert that the correct side effects have happened. What the side effects are will determine how you do the checks.

In your example, you are calling static methods from your non-returning functions, which makes it tricky unless you can inspect that the result of all those static methods are correct. A better way - from a testing point of view - is to inject actual objects in that you call methods on. You can then use something like EasyMock or Mockito to create a Mock Object in your unit test, and inject the mock object into the class. The Mock Object then lets you assert that the correct functions were called, with the correct values and in the correct order.

For example:

private ErrorFile errorFile;

public void setErrorFile(ErrorFile errorFile) {
    this.errorFile = errorFile;
}

private void method1(arg1) {
    if (arg1.indexOf("$") == -1) {

        //Add an error message 
        errorFile.addErrorMessage("There is a dollar sign in the specified parameter");
    }
}

Then in your test you can write:

public void testMethod1() {
    ErrorFile errorFile = EasyMock.createMock(ErrorFile.class);
    errorFile.addErrorMessage("There is a dollar sign in the specified parameter");
    EasyMock.expectLastCall(errorFile);
    EasyMock.replay(errorFile);

    ClassToTest classToTest = new ClassToTest();
    classToTest.setErrorFile(errorFile);
    classToTest.method1("a$b");

    EasyMock.verify(errorFile); // This will fail the test if the required addErrorMessage call didn't happen
}

libclntsh.so.11.1: cannot open shared object file.

I had to install the dependency

oracle-instantclient12.2-basic-12.2.0.1.0-1.x86_64

How do you use bcrypt for hashing passwords in PHP?

Current thinking: hashes should be the slowest available, not the fastest possible. This suppresses rainbow table attacks.

Also related, but precautionary: An attacker should never have unlimited access to your login screen. To prevent that: Set up an IP address tracking table that records every hit along with the URI. If more than 5 attempts to login come from the same IP address in any five minute period, block with explanation. A secondary approach is to have a two-tiered password scheme, like banks do. Putting a lock-out for failures on the second pass boosts security.

Summary: slow down the attacker by using time-consuming hash functions. Also, block on too many accesses to your login, and add a second password tier.

Pass in an enum as a method parameter

First change the method parameter Enum supportedPermissions to SupportedPermissions supportedPermissions.

Then create your file like this

file = new File
{  
    Name = name,
    Id = id,
    Description = description,
    SupportedPermissions = supportedPermissions
};

And the call to your method should be

CreateFile(id, name, description, SupportedPermissions.basic);

Check table exist or not before create it in Oracle

I know this topic is a bit old, but I think I did something that may be useful for someone, so I'm posting it.

I compiled suggestions from this thread's answers into a procedure:

CREATE OR REPLACE PROCEDURE create_table_if_doesnt_exist(
  p_table_name VARCHAR2,
  create_table_query VARCHAR2
) AUTHID CURRENT_USER IS
  n NUMBER;
BEGIN
  SELECT COUNT(*) INTO n FROM user_tables WHERE table_name = UPPER(p_table_name);
  IF (n = 0) THEN
    EXECUTE IMMEDIATE create_table_query;
  END IF;
END;

You can then use it in a following way:

call create_table_if_doesnt_exist('my_table', 'CREATE TABLE my_table (
        id NUMBER(19) NOT NULL PRIMARY KEY,
        text VARCHAR2(4000),
        modified_time TIMESTAMP
  )'
);

I know that it's kinda redundant to pass table name twice, but I think that's the easiest here.

Hope somebody finds above useful :-).

Wpf control size to content?

I had a problem like this whereby I had specified the width of my Window, but had the height set to Auto. The child DockPanel had it's VerticalAlignment set to Top and the Window had it's VerticalContentAlignment set to Top, yet the Window would still be much taller than the contents.

Using Snoop, I discovered that the ContentPresenter within the Window (part of the Window, not something I had put there) has it's VerticalAlignment set to Stretch and can't be changed without retemplating the entire Window!

After a lot of frustration, I discovered the SizeToContent property - you can use this to specify whether you want the Window to size vertically, horizontally or both, according to the size of the contents - everything is sizing nicely now, I just can't believe it took me so long to find that property!

Is there any quick way to get the last two characters in a string?

In my case, I wanted the opposite. I wanted to strip off the last 2 characters in my string. This was pretty simple:

String myString = someString.substring(0, someString.length() - 2);

Calculate difference in keys contained in two Python dictionaries

Based on ghostdog74's answer,

dicta = {"a":1,"d":2}
dictb = {"a":5,"d":2}

for value in dicta.values():
    if not value in dictb.values():
        print value

will print differ value of dicta

Pyspark replace strings in Spark dataframe column

For Spark 1.5 or later, you can use the functions package:

from pyspark.sql.functions import *
newDf = df.withColumn('address', regexp_replace('address', 'lane', 'ln'))

Quick explanation:

  • The function withColumn is called to add (or replace, if the name exists) a column to the data frame.
  • The function regexp_replace will generate a new column by replacing all substrings that match the pattern.

In-place type conversion of a NumPy array

Use this:

In [105]: a
Out[105]: 
array([[15, 30, 88, 31, 33],
       [53, 38, 54, 47, 56],
       [67,  2, 74, 10, 16],
       [86, 33, 15, 51, 32],
       [32, 47, 76, 15, 81]], dtype=int32)

In [106]: float32(a)
Out[106]: 
array([[ 15.,  30.,  88.,  31.,  33.],
       [ 53.,  38.,  54.,  47.,  56.],
       [ 67.,   2.,  74.,  10.,  16.],
       [ 86.,  33.,  15.,  51.,  32.],
       [ 32.,  47.,  76.,  15.,  81.]], dtype=float32)

A simple algorithm for polygon intersection

I have no very simple solution, but here are the main steps for the real algorithm:

  1. Do a custom double linked list for the polygon vertices and edges. Using std::list won't do because you must swap next and previous pointers/offsets yourself for a special operation on the nodes. This is the only way to have simple code, and this will give good performance.
  2. Find the intersection points by comparing each pair of edges. Note that comparing each pair of edge will give O(N²) time, but improving the algorithm to O(N·logN) will be easy afterwards. For some pair of edges (say a?b and c?d), the intersection point is found by using the parameter (from 0 to 1) on edge a?b, which is given by t?=d0/(d0-d1), where d0 is (c-a)×(b-a) and d1 is (d-a)×(b-a). × is the 2D cross product such as p×q=p?·q?-p?·q?. After having found t?, finding the intersection point is using it as a linear interpolation parameter on segment a?b: P=a+t?(b-a)
  3. Split each edge adding vertices (and nodes in your linked list) where the segments intersect.
  4. Then you must cross the nodes at the intersection points. This is the operation for which you needed to do a custom double linked list. You must swap some pair of next pointers (and update the previous pointers accordingly).

Then you have the raw result of the polygon intersection resolving algorithm. Normally, you will want to select some region according to the winding number of each region. Search for polygon winding number for an explanation on this.

If you want to make a O(N·logN) algorithm out of this O(N²) one, you must do exactly the same thing except that you do it inside of a line sweep algorithm. Look for Bentley Ottman algorithm. The inner algorithm will be the same, with the only difference that you will have a reduced number of edges to compare, inside of the loop.

Starting iPhone app development in Linux?

The only way I know of doing development in Linux for the iPhone would be to install Vmware and work on getting OS X running in a virtual machine. With that said there are some "legal" concerns in doing that. It is reported that OS X Server can be virtualized but as far as the development story on that I don't know.

If you are truly serious, that's the what I'd investigate.

Good luck.

EOFException - how to handle?

While reading from the file, your are not terminating your loop. So its read all the values and correctly throws EOFException on the next iteration of the read at line below:

 price = in.readDouble();

If you read the documentation, it says:

Throws:

EOFException - if this input stream reaches the end before reading eight bytes.

IOException - the stream has been closed and the contained input stream does not support reading after close, or another I/O error occurs.

Put a proper termination condition in your while loop to resolve the issue e.g. below:

     while(in.available() > 0)  <--- if there are still bytes to read

Add Favicon to Website

  1. This is not done in PHP. It's part of the <head> tags in a HTML page.
  2. That icon is called a favicon. According to Wikipedia:

    A favicon (short for favorites icon), also known as a shortcut icon, website icon, URL icon, or bookmark icon is a 16×16 or 32×32 pixel square icon associated with a particular website or webpage.

  3. Adding it is easy. Just add an .ico image file that is either 16x16 pixels or 32x32 pixels. Then, in the web pages, add <link rel="shortcut icon" href="favicon.ico" type="image/x-icon"> to the <head> element.
  4. You can easily generate favicons here.

Force IE compatibility mode off using tags

If you want each individual web page to load the chosen content and are using asp.net. Just apply it as the first tag under the heading tag in Views>shared>Layout.cshtml

just a tip

What Ruby IDE do you prefer?

For very simple Linux support if you like TextMate, try just gedit loaded with the right plugins. Easy to set up and really customizable, I use it for just about everything. There's also a lot of talk about emacs plugins if you're already using that normally.

Gedit: How to set up like TextMate

javascript get x and y coordinates on mouse click

It sounds like your printMousePos function should:

  1. Get the X and Y coordinates of the mouse
  2. Add those values to the HTML

Currently, it does this:

  1. Creates (undefined) variables for the X and Y coordinates of the mouse
  2. Attaches a function to the "mousemove" event (which will set those variables to the mouse coordinates when triggered by a mouse move)
  3. Adds the current values of your variables to the HTML

See the problem? Your variables are never getting set, because as soon as you add your function to the "mousemove" event you print them.

It seems like you probably don't need that mousemove event at all; I would try something like this:

function printMousePos(e) {
    var cursorX = e.pageX;
    var cursorY = e.pageY;
    document.getElementById('test').innerHTML = "x: " + cursorX + ", y: " + cursorY;
}

Combine or merge JSON on node.js without jQuery

If using Node version >= 4, use Object.assign() (see Ricardo Nolde's answer).

If using Node 0.x, there is the built in util._extend:

var extend = require('util')._extend
var o = extend({}, {name: "John"});
extend(o,  {location: "San Jose"});

It doesn't do a deep copy and only allows two arguments at a time, but is built in. I saw this mentioned on a question about cloning objects in node: https://stackoverflow.com/a/15040626.

If you're concerned about using a "private" method, you could always proxy it:

// myutil.js
exports.extend = require('util')._extend;

and replace it with your own implementation if it ever disappears. This is (approximately) their implementation:

exports.extend = function(origin, add) {
    if (!add || (typeof add !== 'object' && add !== null)){
        return origin;
    }

    var keys = Object.keys(add);
    var i = keys.length;
    while(i--){
        origin[keys[i]] = add[keys[i]];
    }
    return origin;
};

Fastest way to check if a value exists in a list

def check_availability(element, collection: iter):
    return element in collection

Usage

check_availability('a', [1,2,3,4,'a','b','c'])

I believe this is the fastest way to know if a chosen value is in an array.

What is the problem with shadowing names defined in outer scopes?

A good workaround in some cases may be to move the variables and code to another function:

def print_data(data):
    print data

def main():
    data = [4, 5, 6]
    print_data(data)

main()

vertical divider between two columns in bootstrap

With Bootstrap 4 you can use borders, avoiding writing other CSS.

border-left

And if you want space between content and border you can use padding. (in this example padding left 4px)

pl-4

Example:

_x000D_
_x000D_
    <link href="https://stackpath.bootstrapcdn.com/bootstrap/4.4.1/css/bootstrap.min.css" rel="stylesheet"/>_x000D_
_x000D_
    <div class="row">_x000D_
      <div class="offset-6 border-left pl-4">First</div>_x000D_
      <div class="offset-6 border-left pl-4">Second</div>_x000D_
    </div>
_x000D_
_x000D_
_x000D_

String representation of an Enum

My answer, working on @user29964 's answer (which is by far the simplest and closest to a Enum) is

 public class StringValue : System.Attribute
    {
        private string _value;

        public StringValue(string value)
        {
            _value = value;
        }

        public string Value
        {
            get { return _value; }
        }



        public static string GetStringValue(Enum Flagvalue)
        {
            Type type = Flagvalue.GetType();
            string[] flags = Flagvalue.ToString().Split(',').Select(x => x.Trim()).ToArray();
            List<string> values = new List<string>();

            for (int i = 0; i < flags.Length; i++)
            {

                FieldInfo fi = type.GetField(flags[i].ToString());

                StringValue[] attrs =
                   fi.GetCustomAttributes(typeof(StringValue),
                                           false) as StringValue[];
                if (attrs.Length > 0)
                {
                    values.Add(attrs[0].Value);
                }
            }
            return String.Join(",", values);

        }

usage

[Flags]
    public enum CompeteMetric
    {

        /// <summary>
        /// u
        /// </summary>
        [StringValue("u")]//Json mapping
        Basic_UniqueVisitors = 1 //Basic
             ,
        /// <summary>
        /// vi
        /// </summary>
        [StringValue("vi")]//json mapping
        Basic_Visits = 2// Basic
            ,
        /// <summary>
        /// rank
        /// </summary>
        [StringValue("rank")]//json mapping
        Basic_Rank = 4//Basic
 }

Example

        CompeteMetric metrics = CompeteMetric.Basic_Visits | CompeteMetric.Basic_Rank;
        string strmetrics = StringValue.GetStringValue(metrics);

this will return "vi,rank"

Spring AMQP + RabbitMQ 3.3.5 ACCESS_REFUSED - Login was refused using authentication mechanism PLAIN

The error

ACCESS_REFUSED - Login was refused using authentication mechanism PLAIN. For details see the broker logfile.

can occur if the credentials that your application is trying to use to connect to RabbitMQ are incorrect or missing.

I had this happen when the RabbitMQ credentials stored in my ASP.NET application's web.config file had a value of "" for the password instead of the actual password string value.

Is System.nanoTime() completely useless?

This doesn't seem to be a problem on a Core 2 Duo running Windows XP and JRE 1.5.0_06.

In a test with three threads I don't see System.nanoTime() going backwards. The processors are both busy, and threads go to sleep occasionally to provoke moving threads around.

[EDIT] I would guess that it only happens on physically separate processors, i.e. that the counters are synchronized for multiple cores on the same die.

Add a space (" ") after an element using :after

I needed this instead of using padding because I used inline-block containers to display a series of individual events in a workflow timeline. The last event in the timeline needed no arrow after it.

Ended up with something like:

.transaction-tile:after {
  content: "\f105";
}

.transaction-tile:last-child:after {
  content: "\00a0";
}

Used fontawesome for the gt (chevron) character. For whatever reason "content: none;" was producing alignment issues on the last tile.

iPad Safari scrolling causes HTML elements to disappear and reappear with a delay

There are cases where a rotation is applied and/or a Z index is used.

Rotation: An existing declaration of -webkit-transform to rotate an element might not be enough to tackle the appearance problem as well (like -webkit-transform: rotate(-45deg)). In this case you can use -webkit-transform: translateZ(0px) rotateZ(-45deg) as a trick (mind the rotateZ).

Z index: Together with the rotation you might define a positive z-index property, like z-index: 42. The above steps described under "Rotation" were in my case enough to resolve the issue, even with the empty translateZ(0px). I suspect though that the Z index in this case may have caused the disappearing and reappearing in the first place. In any case the z-index: 42 property needs to be kept -- -webkit-transform: translateZ(42px) only is not enough.

npm install error - unable to get local issuer certificate

Anyone gets this error when 'npm install' is trying to fetch a package from HTTPS server with a self-signed or invalid certificate.

Quick and insecure solution:

npm config set strict-ssl false

Why this solution is insecure? The above command tells npm to connect and fetch module from server even server do not have valid certificate and server identity is not verified. So if there is a proxy server between npm client and actual server, it provided man in middle attack opportunity to an intruder.

Secure solution:

If any module in your package.json is hosted on a server with self-signed CA certificate then npm is unable to identify that server with an available system CA certificates. So you need to provide CA certificate for server validation with the explicit configuration in .npmrc. In .npmrc you need to provide cafile, please refer more detail about cafile configuration here

cafile=./ca-certs.pem

In ca-certs file, you can add any number of CA certificates(public) that you required to identify servers. The certificate should be in “Base-64 encoded X.509 (.CER)(PEM)” format.

For example,

# cat ca-certs.pem 
DigiCert Global Root CA
=======================
-----BEGIN CERTIFICATE-----
CAUw7C29C79Fv1C5qfPrmAE.....
-----END CERTIFICATE-----

VeriSign Class 3 Public Primary Certification Authority - G5
========================================
-----BEGIN CERTIFICATE-----
MIIE0zCCA7ugAwIBAgIQ......
-----END CERTIFICATE-----

Note: once you provide cafile configuration in .npmrc, npm try to identify all server using CA certificate(s) provided in cafile only, it won't check system CA certificate bundles then. If someone wants all well-known public CA authority certificat bundle then can get from here.

One other situation when you get this error:

If you have mentioned Git URL as a dependency in package.json and git is on invalid/self-signed certificate then also npm throws a similar error. You can fix it with following configuration for git client

git config --global http.sslVerify false 

When do I need a fb:app_id or fb:admins?

Including the fb:app_id tag in your HTML HEAD will allow the Facebook scraper to associate the Open Graph entity for that URL with an application. This will allow any admins of that app to view Insights about that URL and any social plugins connected with it.

The fb:admins tag is similar, but allows you to just specify each user ID that you would like to give the permission to do the above.

You can include either of these tags or both, depending on how many people you want to admin the Insights, etc. A single as fb:admins is pretty much a minimum requirement. The rest of the Open Graph tags will still be picked up when people share and like your URL, however it may cause problems in the future, so please include one of the above.

fb:admins is specified like this:
<meta property="fb:admins" content="USER_ID"/>
OR
<meta property="fb:admins" content="USER_ID,USER_ID2,USER_ID3"/>

and fb:app_id like this:
<meta property="fb:app_id" content="APPID"/>

how to call a onclick function in <a> tag?

Fun! There are a few things to tease out here:

  • $leadID seems to be a php string. Make sure it gets printed in the right place. Also be aware of all the risks involved in passing your own strings around, like cross-site scripting and SQL injection vulnerabilities. There’s really no excuse for having Internet-facing production code not running on a solid framework.
  • Strings in Javascript (like in PHP and usually HTML) need to be enclosed in " or ' characters. Since you’re already inside both " and ', you’ll want to escape whichever you choose. \' to escape the PHP quotes, or &apos; to escape the HTML quotes.
  • <a /> elements are commonly used for “hyper”links, and almost always with a href attribute to indicate their destination, like this: <a href="http://www.google.com">Google homepage</a>.
  • You’re trying to double up on watching when the user clicks. Why? Because a standard click both activates the link (causing the browser to navigate to whatever URL, even that executes Javascript), and “triggers” the onclick event. Tip: Add a return false; to a Javascript event to suppress default behavior.
  • Within Javascript, onclick doesn’t mean anything on its own. That’s because onclick is a property, and not a variable. There has to be a reference to some object, so it knows whose onclick we’re talking about! One such object is window. You could write <a href="javascript:window.onclick = location.reload;">Activate me to reload when anything is clicked</a>.
  • Within HTML, onclick can mean something on its own, as long as its part of an HTML tag: <a href="#" onclick="location.reload(); return false;">. I bet you had this in mind.
  • Big difference between those two kinds of = assignments. The Javascript = expects something that hasn’t been run yet. You can wrap things in a function block to signal code that should be run later, if you want to specify some arguments now (like I didn’t above with reload): <a href="javascript:window.onclick = function () { window.open( ... ) };"> ....
  • Did you know you don’t even need to use Javascript to signal the browser to open a link in a new window? There’s a special target attribute for that: <a href="http://www.google.com" target="_blank">Google homepage</a>.

Hope those are useful.

Calculate time difference in minutes in SQL Server

Use DateDiff with MINUTE difference:

SELECT DATEDIFF(MINUTE, '11:10:10' , '11:20:00') AS MinuteDiff

Query that may help you:

SELECT StartTime, EndTime, DATEDIFF(MINUTE, StartTime , EndTime) AS MinuteDiff 
FROM TableName

Best way to create unique token in Rails?

This might be a late response but in order to avoid using a loop you can also call the method recursively. It looks and feels slightly cleaner to me.

class ModelName < ActiveRecord::Base

  before_create :generate_token

  protected

  def generate_token
    self.token = SecureRandom.urlsafe_base64
    generate_token if ModelName.exists?(token: self.token)
  end

end

URL to compose a message in Gmail (with full Gmail interface and specified to, bcc, subject, etc.)

The GMail web client supports mailto: links

For regular @gmail.com accounts: https://mail.google.com/mail/?extsrc=mailto&url=...

For G Suite accounts on domain gsuitedomain.com: https://mail.google.com/a/gsuitedomain.com/mail/?extsrc=mailto&url=...

... needs to be replaced with a urlencoded mailto: link.

Demo: https://mail.google.com/mail/?extsrc=mailto&url=mailto%3A%3Fto%3Dsomeguy%40gmail.com%26bcc%3Dmyattorney%40gmail.com%2Cbuzzfeed%40gmail.com%26subject%3DHi%2520There%26body%3Dbody%2520goes%2520here

Learn more about mailto: links by reading RFC6068

Pandas convert dataframe to array of tuples

Motivation
Many data sets are large enough that we need to concern ourselves with speed/efficiency. So I offer this solution in that spirit. It happens to also be succinct.

For the sake of comparison, let's drop the index column

df = data_set.drop('index', 1)

Solution
I'll propose the use of zip and map

list(zip(*map(df.get, df)))

[('2012-02-17', 24.75, 25.03),
 ('2012-02-16', 25.0, 25.07),
 ('2012-02-15', 24.99, 25.15),
 ('2012-02-14', 24.68, 25.05),
 ('2012-02-13', 24.62, 24.77),
 ('2012-02-10', 24.38, 24.61)]

It happens to also be flexible if we wanted to deal with a specific subset of columns. We'll assume the columns we've already displayed are the subset we want.

list(zip(*map(df.get, ['data_date', 'data_1', 'data_2'])))

[('2012-02-17', 24.75, 25.03),
 ('2012-02-16', 25.0, 25.07),
 ('2012-02-15', 24.99, 25.15),
 ('2012-02-14', 24.68, 25.05),
 ('2012-02-13', 24.62, 24.77),
 ('2012-02-10', 24.38, 24.61)]

What is Quicker?

Turn's out records is quickest followed by asymptotically converging zipmap and iter_tuples

I'll use a library simple_benchmarks that I got from this post

from simple_benchmark import BenchmarkBuilder
b = BenchmarkBuilder()

import pandas as pd
import numpy as np

def tuple_comp(df): return [tuple(x) for x in df.to_numpy()]
def iter_namedtuples(df): return list(df.itertuples(index=False))
def iter_tuples(df): return list(df.itertuples(index=False, name=None))
def records(df): return df.to_records(index=False).tolist()
def zipmap(df): return list(zip(*map(df.get, df)))

funcs = [tuple_comp, iter_namedtuples, iter_tuples, records, zipmap]
for func in funcs:
    b.add_function()(func)

def creator(n):
    return pd.DataFrame({"A": random.randint(n, size=n), "B": random.randint(n, size=n)})

@b.add_arguments('Rows in DataFrame')
def argument_provider():
    for n in (10 ** (np.arange(4, 11) / 2)).astype(int):
        yield n, creator(n)

r = b.run()

Check the results

r.to_pandas_dataframe().pipe(lambda d: d.div(d.min(1), 0))

        tuple_comp  iter_namedtuples  iter_tuples   records    zipmap
100       2.905662          6.626308     3.450741  1.469471  1.000000
316       4.612692          4.814433     2.375874  1.096352  1.000000
1000      6.513121          4.106426     1.958293  1.000000  1.316303
3162      8.446138          4.082161     1.808339  1.000000  1.533605
10000     8.424483          3.621461     1.651831  1.000000  1.558592
31622     7.813803          3.386592     1.586483  1.000000  1.515478
100000    7.050572          3.162426     1.499977  1.000000  1.480131

r.plot()

enter image description here

How to iterate over rows in a DataFrame in Pandas

cs95 shows that Pandas vectorization far outperforms other Pandas methods for computing stuff with dataframes.

I wanted to add that if you first convert the dataframe to a NumPy array and then use vectorization, it's even faster than Pandas dataframe vectorization, (and that includes the time to turn it back into a dataframe series).

If you add the following functions to cs95's benchmark code, this becomes pretty evident:

def np_vectorization(df):
    np_arr = df.to_numpy()
    return pd.Series(np_arr[:,0] + np_arr[:,1], index=df.index)

def just_np_vectorization(df):
    np_arr = df.to_numpy()
    return np_arr[:,0] + np_arr[:,1]

Enter image description here

MySQL: can't access root account

You can use the init files. Check the MySQL official documentation on How to Reset the Root Password (including comments for alternative solutions).

So basically using init files, you can add any SQL queries that you need for fixing your access (such as GRAND, CREATE, FLUSH PRIVILEGES, etc.) into init file (any file).

Here is my example of recovering root account:

echo "CREATE USER 'root'@'localhost' IDENTIFIED BY 'root';" > your_init_file.sql
echo "GRANT ALL PRIVILEGES ON *.* TO 'root'@'localhost' WITH GRANT OPTION;" >> your_init_file.sql 
echo "FLUSH PRIVILEGES;" >> your_init_file.sql

and after you've created your file, you can run:

killall mysqld
mysqld_safe --init-file=$PWD/your_init_file.sql

then to check if this worked, press Ctrl+Z and type: bg to run the process from the foreground into the background, then verify your access by:

mysql -u root -proot
mysql> show grants;
+-------------------------------------------------------------------------------------------------------------+
| Grants for root@localhost                                                                                   |
+-------------------------------------------------------------------------------------------------------------+
| GRANT USAGE ON *.* TO 'root'@'localhost' IDENTIFIED BY PASSWORD '*81F5E21E35407D884A6CD4A731AEBFB6AF209E1B' |

See also:

Is an HTTPS query string secure?

SSL first connects to the host, so the host name and port number are transferred as clear text. When the host responds and the challenge succeeds, the client will encrypt the HTTP request with the actual URL (i.e. anything after the third slash) and and send it to the server.

There are several ways to break this security.

It is possible to configure a proxy to act as a "man in the middle". Basically, the browser sends the request to connect to the real server to the proxy. If the proxy is configured this way, it will connect via SSL to the real server but the browser will still talk to the proxy. So if an attacker can gain access of the proxy, he can see all the data that flows through it in clear text.

Your requests will also be visible in the browser history. Users might be tempted to bookmark the site. Some users have bookmark sync tools installed, so the password could end up on deli.ci.us or some other place.

Lastly, someone might have hacked your computer and installed a keyboard logger or a screen scraper (and a lot of Trojan Horse type viruses do). Since the password is visible directly on the screen (as opposed to "*" in a password dialog), this is another security hole.

Conclusion: When it comes to security, always rely on the beaten path. There is just too much that you don't know, won't think of and which will break your neck.

How to replace comma (,) with a dot (.) using java

str = str.replace(',', '.')

should do the trick.

read file in classpath

import java.io.BufferedReader;
import java.io.File;
import java.io.FileNotFoundException;
import java.io.FileReader;
import java.io.IOException;

public class readFile {
    /**
     * feel free to make any modification I have have been here so I feel you
     * 
     * @param args
     * @throws InterruptedException
     */
    public static void main(String[] args) throws InterruptedException {
        File dir = new File(".");// read file from same directory as source //
        if (dir.isDirectory()) {
            File[] files = dir.listFiles();
            for (File file : files) {
                // if you wanna read file name with txt files
                if (file.getName().contains("txt")) {
                    System.out.println(file.getName());
                }

                // if you want to open text file and read each line then
                if (file.getName().contains("txt")) {
                    try {
                        // FileReader reads text files in the default encoding.
                        FileReader fileReader = new FileReader(
                                file.getAbsolutePath());
                        // Always wrap FileReader in BufferedReader.
                        BufferedReader bufferedReader = new BufferedReader(
                                fileReader);
                        String line;
                        // get file details and get info you need.
                        while ((line = bufferedReader.readLine()) != null) {
                            System.out.println(line);
                            // here you can say...
                            // System.out.println(line.substring(0, 10)); this
                            // prints from 0 to 10 indext
                        }
                    } catch (FileNotFoundException ex) {
                        System.out.println("Unable to open file '"
                                + file.getName() + "'");
                    } catch (IOException ex) {
                        System.out.println("Error reading file '"
                                + file.getName() + "'");
                        // Or we could just do this:
                        ex.printStackTrace();
                    }
                }
            }
        }

    }`enter code here`

}

Error:(23, 17) Failed to resolve: junit:junit:4.12

If you're behind a proxy server, just add your proxy settings in gradle.properties

systemProp.http.proxyHost=x.xx.xx.x

systemProp.http.proxyPort=xxxx

systemProp.https.proxyHost=x.xx.xx.x

systemProp.https.proxyPort=xxxx

It worked for me.

Simulate low network connectivity for Android

as suggested by @VicVu Charles (or any other proxy tool) is an easier way to go. But I would Like to add that you can do this with your device also, not just genymotion or other emulators. Process will be the same:

Modify your device/emulator's wifi setting to use manual proxy. And then Set the Proxy hostname & port a. set the hostname as ip of your system (get the ip of your pc/mac using ifconfig/ifconfig) b. set the port number of genymotion (check the proxy settings in charles)

PS: Your device/emulator MUST be using the same wifi since the ip you are using will most probably be the private ip.

2 "style" inline css img tags?

Do not use more than one style attribute. Just seperate styles in the style attribute with ; It is a block of inline CSS, so think of this as you would do CSS in a separate stylesheet.

So in this case its: style="height:100px;width:100px;"

You can use this for any CSS style, so if you wanted to change the colour of the text to white: style="height:100px;width:100px;color:#ffffff" and so on.

However, it is worth using inline CSS sparingly, as it can make code less manageable in future. Using an external stylesheet may be a better option for this. It depends really on your requirements. Inline CSS does make for quicker coding.

Understanding the grid classes ( col-sm-# and col-lg-# ) in Bootstrap 3

This might be late as I think most of us are using BS4. This article explained all the questions you asked in a detailed and simple manner also includes what to do when. The detailed guide to use bs4 or bootstrap

https://uxplanet.org/how-the-bootstrap-4-grid-works-a1b04703a3b7

Normalizing images in OpenCV

The other answers normalize an image based on the entire image. But if your image has a predominant color (such as black), it will mask out the features that you're trying to enhance since it will not be as pronounced. To get around this limitation, we can normalize the image based on a subsection region of interest (ROI). Essentially we will normalize based on the section of the image that we want to enhance instead of equally treating each pixel with the same weight. Take for instance this earth image:

Input image -> Normalization based on entire image

If we want to enhance the clouds by normalizing based on the entire image, the result will not be very sharp and will be over saturated due to the black background. The features to enhance are lost. So to obtain a better result we can crop a ROI, normalize based on the ROI, and then apply the normalization back onto the original image. Say we crop the ROI highlighted in green:

This gives us this ROI

The idea is to calculate the mean and standard deviation of the ROI and then clip the frame based on the lower and upper range. In addition, we could use an offset to dynamically adjust the clip intensity. From here we normalize the original image to this new range. Here's the result:

Before -> After

Code

import cv2
import numpy as np

# Load image as grayscale and crop ROI
image = cv2.imread('1.png', 0)
x, y, w, h = 364, 633, 791, 273
ROI = image[y:y+h, x:x+w]

# Calculate mean and STD
mean, STD  = cv2.meanStdDev(ROI)

# Clip frame to lower and upper STD
offset = 0.2
clipped = np.clip(image, mean - offset*STD, mean + offset*STD).astype(np.uint8)

# Normalize to range
result = cv2.normalize(clipped, clipped, 0, 255, norm_type=cv2.NORM_MINMAX)

cv2.imshow('image', image)
cv2.imshow('ROI', ROI)
cv2.imshow('result', result)
cv2.waitKey()

The difference between normalizing based on the entire image vs a specific section of the ROI can be visualized by applying a heatmap to the result. Notice the difference on how the clouds are defined.

Input image -> heatmap

Normalized on entire image -> heatmap

Normalized on ROI -> heatmap

Heatmap code

import matplotlib.pyplot as plt
import numpy as np
import cv2

image = cv2.imread('result.png', 0)
colormap = plt.get_cmap('inferno')
heatmap = (colormap(image) * 2**16).astype(np.uint16)[:,:,:3]
heatmap = cv2.cvtColor(heatmap, cv2.COLOR_RGB2BGR)

cv2.imshow('image', image)
cv2.imshow('heatmap', heatmap)
cv2.waitKey()

Note: The ROI bounding box coordinates were obtained using how to get ROI Bounding Box Coordinates without Guess & Check and heatmap code was from how to convert a grayscale image to heatmap image with Python OpenCV

Convert a PHP script into a stand-alone windows executable

I had problems with most of the tools in other answers as they are all very outdated.

If you need a solution that will "just work", pack a bare-bones version of php with your project in a WinRar SFX archive, set it to extract everything to a temporary directory and execute php your_script.php.

To run a basic script, the only files required are php.exe and php5.dll (or php5ts.dll depending on version).

To add extensions, pack them along with a php.ini file:

[PHP]
extension_dir = "."
extension=php_curl.dll
extension=php_xxxx.dll
...

How to get SQL from Hibernate Criteria API (*not* for logging)

For anyone wishing to do this in a single line (e.g in the Display/Immediate window, a watch expression or similar in a debug session), the following will do so and "pretty print" the SQL:

new org.hibernate.jdbc.util.BasicFormatterImpl().format((new org.hibernate.loader.criteria.CriteriaJoinWalker((org.hibernate.persister.entity.OuterJoinLoadable)((org.hibernate.impl.CriteriaImpl)crit).getSession().getFactory().getEntityPersister(((org.hibernate.impl.CriteriaImpl)crit).getSession().getFactory().getImplementors(((org.hibernate.impl.CriteriaImpl)crit).getEntityOrClassName())[0]),new org.hibernate.loader.criteria.CriteriaQueryTranslator(((org.hibernate.impl.CriteriaImpl)crit).getSession().getFactory(),((org.hibernate.impl.CriteriaImpl)crit),((org.hibernate.impl.CriteriaImpl)crit).getEntityOrClassName(),org.hibernate.loader.criteria.CriteriaQueryTranslator.ROOT_SQL_ALIAS),((org.hibernate.impl.CriteriaImpl)crit).getSession().getFactory(),(org.hibernate.impl.CriteriaImpl)crit,((org.hibernate.impl.CriteriaImpl)crit).getEntityOrClassName(),((org.hibernate.impl.CriteriaImpl)crit).getSession().getEnabledFilters())).getSQLString());

...or here's an easier to read version:

new org.hibernate.jdbc.util.BasicFormatterImpl().format(
  (new org.hibernate.loader.criteria.CriteriaJoinWalker(
     (org.hibernate.persister.entity.OuterJoinLoadable)
      ((org.hibernate.impl.CriteriaImpl)crit).getSession().getFactory().getEntityPersister(
        ((org.hibernate.impl.CriteriaImpl)crit).getSession().getFactory().getImplementors(
          ((org.hibernate.impl.CriteriaImpl)crit).getEntityOrClassName())[0]),
     new org.hibernate.loader.criteria.CriteriaQueryTranslator(
          ((org.hibernate.impl.CriteriaImpl)crit).getSession().getFactory(),
          ((org.hibernate.impl.CriteriaImpl)crit),
          ((org.hibernate.impl.CriteriaImpl)crit).getEntityOrClassName(),
          org.hibernate.loader.criteria.CriteriaQueryTranslator.ROOT_SQL_ALIAS),
     ((org.hibernate.impl.CriteriaImpl)crit).getSession().getFactory(),
     (org.hibernate.impl.CriteriaImpl)crit,
     ((org.hibernate.impl.CriteriaImpl)crit).getEntityOrClassName(),
     ((org.hibernate.impl.CriteriaImpl)crit).getSession().getEnabledFilters()
   )
  ).getSQLString()
);

Notes:

  1. The answer is based on the solution posted by ramdane.i.
  2. It assumes the Criteria object is named crit. If named differently, do a search and replace.
  3. It assumes the Hibernate version is later than 3.3.2.GA but earlier than 4.0 in order to use BasicFormatterImpl to "pretty print" the HQL. If using a different version, see this answer for how to modify. Or perhaps just remove the pretty printing entirely as it's just a "nice to have".
  4. It's using getEnabledFilters rather than getLoadQueryInfluencers() for backwards compatibility since the latter was introduced in a later version of Hibernate (3.5???)
  5. It doesn't output the actual parameter values used if the query is parameterized.

Laravel 5.2 redirect back with success message

You can simply use back() function to redirect no need to use redirect()->back() make sure you are using 5.2 or greater than 5.2 version.

You can replace your code to below code.

return back()->with('message', 'WORKS!');

In the view file replace below code.

@if(session()->has('message'))
    <div class="alert alert-success">
        {{ session()->get('message') }}
    </div>
@endif

For more detail, you can read here

back() is just a helper function. It's doing the same thing as redirect()->back()

How to scroll the window using JQuery $.scrollTo() function

$('html, body').animate({scrollTop: $("#page").offset().top}, 2000);

Setting default permissions for newly created files and sub-directories under a directory in Linux?

It's ugly, but you can use the setfacl command to achieve exactly what you want.

On a Solaris machine, I have a file that contains the acls for users and groups. Unfortunately, you have to list all of the users (at least I couldn't find a way to make this work otherwise):

user::rwx
user:user_a:rwx
user:user_b:rwx
...
group::rwx
mask:rwx
other:r-x
default:user:user_a:rwx
default:user:user_b:rwx
....
default:group::rwx
default:user::rwx
default:mask:rwx
default:other:r-x

Name the file acl.lst and fill in your real user names instead of user_X.

You can now set those acls on your directory by issuing the following command:

setfacl -f acl.lst /your/dir/here

Attach a file from MemoryStream to a MailMessage in C#

Since I couldn't find confirmation of this anywhere, I tested if disposing of the MailMessage and/or the Attachment object would dispose of the stream loaded into them as I expected would happen.

It does appear with the following test that when the MailMessage is disposed, all streams used to create attachments will also be disposed. So as long as you dispose your MailMessage the streams that went into creating it do not need handling beyond that.

MailMessage mail = new MailMessage();
//Create a MemoryStream from a file for this test
MemoryStream ms = new MemoryStream(File.ReadAllBytes(@"C:\temp\test.gif"));

mail.Attachments.Add(new System.Net.Mail.Attachment(ms, "test.gif"));
if (mail.Attachments[0].ContentStream == ms) Console.WriteLine("Streams are referencing the same resource");
Console.WriteLine("Stream length: " + mail.Attachments[0].ContentStream.Length);

//Dispose the mail as you should after sending the email
mail.Dispose();
//--Or you can dispose the attachment itself
//mm.Attachments[0].Dispose();

Console.WriteLine("This will throw a 'Cannot access a closed Stream.' exception: " + ms.Length);

"column not allowed here" error in INSERT statement

This error creeps in if we make some spelling mistake in entering the variable name. Like in stored proc, I have the variable name x and in my insert statement I am using

insert into tablename values(y);

It will throw an error column not allowed here.

How to sort a Pandas DataFrame by index?

Slightly more compact:

df = pd.DataFrame([1, 2, 3, 4, 5], index=[100, 29, 234, 1, 150], columns=['A'])
df = df.sort_index()
print(df)

Note:

Error: Cannot find module '../lib/utils/unsupported.js' while using Ionic

In my case it was $NODE_PATH missing:

NODE="/home/ubuntu/local/node" #here your user account after home
NODE_PATH="/usr/local/lib/node_modules" 
PATH="$PATH:/usr/local/sbin:/usr/local/bin:/usr/sbin:/usr/bin:/sbin:/bin:/usr/games:$NODE/bin:$NODE/lib/node_modules"

To check just echo $NODE_PATH empty means it is not set. Add them to .bashrc is recommended.

How to Retrieve value from JTextField in Java Swing?

* First we declare JTextField like this

 JTextField  testField = new JTextField(10);

* We can get textfield value in String like this on any button click event.

button.addActionListener(new ActionListener(){
   public void actionPerformed(ActionEvent ae){
      String getValue = testField.getText()

   }
})

Keras model.summary() result - Understanding the # of Parameters

I feed a 514 dimensional real-valued input to a Sequential model in Keras. My model is constructed in following way :

    predictivemodel = Sequential()
    predictivemodel.add(Dense(514, input_dim=514, W_regularizer=WeightRegularizer(l1=0.000001,l2=0.000001), init='normal'))
    predictivemodel.add(Dense(257, W_regularizer=WeightRegularizer(l1=0.000001,l2=0.000001), init='normal'))
    predictivemodel.compile(loss='mean_squared_error', optimizer='adam', metrics=['accuracy'])

When I print model.summary() I get following result:

Layer (type)    Output Shape  Param #     Connected to                   
================================================================
dense_1 (Dense) (None, 514)   264710      dense_input_1[0][0]              
________________________________________________________________
activation_1    (None, 514)   0           dense_1[0][0]                    
________________________________________________________________
dense_2 (Dense) (None, 257)   132355      activation_1[0][0]               
================================================================
Total params: 397065
________________________________________________________________ 

For the dense_1 layer , number of params is 264710. This is obtained as : 514 (input values) * 514 (neurons in the first layer) + 514 (bias values)

For dense_2 layer, number of params is 132355. This is obtained as : 514 (input values) * 257 (neurons in the second layer) + 257 (bias values for neurons in the second layer)

Error: " 'dict' object has no attribute 'iteritems' "

As you are in python3 , use dict.items() instead of dict.iteritems()

iteritems() was removed in python3, so you can't use this method anymore.

Take a look at Python 3.0 Wiki Built-in Changes section, where it is stated:

Removed dict.iteritems(), dict.iterkeys(), and dict.itervalues().

Instead: use dict.items(), dict.keys(), and dict.values() respectively.

How to print register values in GDB?

If you're trying to print a specific register in GDB, you have to omit the % sign. For example,

info registers eip

If your executable is 64 bit, the registers start with r. Starting them with e is not valid.

info registers rip

Those can be abbreviated to:

i r rip

Import CSV to SQLite

Here's how I did it.

  • Make/Convert csv file to be seperated by tabs (\t) AND not enclosed by any quotes (sqlite interprets quotes literally - says old docs)
  • Enter the sqlite shell of the db to which the data needs to be added

    sqlite> .separator "\t" ---IMPORTANT! should be in double quotes sqlite> .import afile.csv tablename-to-import-to

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 :)

On Windows, running "import tensorflow" generates No module named "_pywrap_tensorflow" error

The problem was the cuDNN Library for me - for whatever reason cudnn-8.0-windows10-x64-v6.0 was NOT working - I used cudnn-8.0-windows10-x64-v5.1 - ALL GOOD!

My setup working with Win10 64 and the Nvidia GTX780M:

  • Be sure you have the lib MSVCP140.DLL by checking your system/path - if not get it here
  • Run the windows installer for python 3.5.3-amd64 from here - DO NOT try newer versions as they probably won't work
  • Get the cuDNN v5.1 for CUDA 8.0 from here - put it under your users folder or in another known location (you will need this in your path)
  • Get CUDA 8.0 x86_64 from here
  • Set PATH vars as expected to point at the cuDNN libs and python (the python path should be added during the python install)
  • Make sure that ".DLL" is included in your PATHEXT variable
  • If you are using tensorflow 1.3 then you want to use cudnn64_6.dll github.com/tensorflow/tensorflow/issues/7705

If you run Windows 32 be sure to get the 32 bit versions of the files mentioned above.

Database Diagram Support Objects cannot be Installed ... no valid owner

The real problem is that the default owner(dbo) doesn't have a login mapped to it at all.As I tried to map the sa login to the database owner I received another error stating "User,group, or role 'dbo' already exists...".However if you try this code it will actually works :

EXEC sp_dbcmptlevel 'yourDB', '90';

go

ALTER AUTHORIZATION ON DATABASE::yourDB TO "yourLogin"

go

use [yourDB]

go

EXECUTE AS USER = N'dbo' REVERT

go

How to pass a Javascript Array via JQuery Post so that all its contents are accessible via the PHP $_POST array?

I think we should sent in this format

var array = [1, 2, 3, 4, 5];
$.post('/controller/MyAction', $.param({ data: array }, true), function(data) {});

Its already mentioned in Pass array to mvc Action via AJAX

It worked for me

Removing nan values from an array

As shown by others

x[~numpy.isnan(x)]

works. But it will throw an error if the numpy dtype is not a native data type, for example if it is object. In that case you can use pandas.

x[~pandas.isna(x)] or x[~pandas.isnull(x)]

QByteArray to QString

You can use:

QString::fromStdString(byteArray.toStdString())

How to check if a string contains an element from a list in Python

It is better to parse the URL properly - this way you can handle http://.../file.doc?foo and http://.../foo.doc/file.exe correctly.

from urlparse import urlparse
import os
path = urlparse(url_string).path
ext = os.path.splitext(path)[1]
if ext in extensionsToCheck:
  print(url_string)

How to open a new form from another form

I would use a value that gets set when more button get pushed closed the first dialog and then have the original form test the value and then display the the there dialog.

For the Ex

  1. Create three windows froms
  2. Form1 Form2 Form3
  3. Add One button to Form1
  4. Add Two buttons to form2

Form 1 Code

 public partial class Form1 : Form
{
    public Form1()
    {
        InitializeComponent();
    }

    private bool DrawText = false;

    private void button1_Click(object sender, EventArgs e)
    {
        Form2 f2 = new Form2();
        f2.ShowDialog();
        if (f2.ShowMoreActions)
        {
            Form3 f3 = new Form3();
            f3.ShowDialog();
        }

    }

Form2 code

 public partial class Form2 : Form
 {
        public Form2()
        {
            InitializeComponent();
        }

        public bool ShowMoreActions = false;
        private void button1_Click(object sender, EventArgs e)
        {
            ShowMoreActions = true;
            this.Close();
        }


        private void button2_Click(object sender, EventArgs e)
        {
            this.Close();
        }
    }

Leave form3 as is

#pragma pack effect

I have seen people use it to make sure that a structure takes a whole cache line to prevent false sharing in a multithreaded context. If you are going to have a large number of objects that are going to be loosely packed by default it could save memory and improve cache performance to pack them tighter, though unaligned memory access will usually slow things down so there might be a downside.

How to pass a type as a method parameter in Java

I had a similar question, so I worked up a complete runnable answer below. What I needed to do is pass a class (C) to an object (O) of an unrelated class and have that object (O) emit new objects of class (C) back to me when I asked for them.

The example below shows how this is done. There is a MagicGun class that you load with any subtype of the Projectile class (Pebble, Bullet or NuclearMissle). The interesting is you load it with subtypes of Projectile, but not actual objects of that type. The MagicGun creates the actual object when it's time to shoot.

The Output

You've annoyed the target!
You've holed the target!
You've obliterated the target!
click
click

The Code

import java.util.ArrayList;
import java.util.List;

public class PassAClass {
    public static void main(String[] args) {
        MagicGun gun = new MagicGun();
        gun.loadWith(Pebble.class);
        gun.loadWith(Bullet.class);
        gun.loadWith(NuclearMissle.class);
        //gun.loadWith(Object.class);   // Won't compile -- Object is not a Projectile
        for(int i=0; i<5; i++){
            try {
                String effect = gun.shoot().effectOnTarget();
                System.out.printf("You've %s the target!\n", effect);
            } catch (GunIsEmptyException e) {
                System.err.printf("click\n");
            }
        }
    }
}

class MagicGun {
    /**
     * projectiles holds a list of classes that extend Projectile. Because of erasure, it
     * can't hold be a List<? extends Projectile> so we need the SuppressWarning. However
     * the only way to add to it is the "loadWith" method which makes it typesafe. 
     */
    private @SuppressWarnings("rawtypes") List<Class> projectiles = new ArrayList<Class>();
    /**
     * Load the MagicGun with a new Projectile class.
     * @param projectileClass The class of the Projectile to create when it's time to shoot.
     */
    public void loadWith(Class<? extends Projectile> projectileClass){
        projectiles.add(projectileClass);
    }
    /**
     * Shoot the MagicGun with the next Projectile. Projectiles are shot First In First Out.
     * @return A newly created Projectile object.
     * @throws GunIsEmptyException
     */
    public Projectile shoot() throws GunIsEmptyException{
        if (projectiles.isEmpty())
            throw new GunIsEmptyException();
        Projectile projectile = null;
        // We know it must be a Projectile, so the SuppressWarnings is OK
        @SuppressWarnings("unchecked") Class<? extends Projectile> projectileClass = projectiles.get(0);
        projectiles.remove(0);
        try{
            // http://www.java2s.com/Code/Java/Language-Basics/ObjectReflectioncreatenewinstance.htm
            projectile = projectileClass.newInstance();
        } catch (InstantiationException e) {
            System.err.println(e);
        } catch (IllegalAccessException e) {
            System.err.println(e);
        }
        return projectile;
    }
}

abstract class Projectile {
    public abstract String effectOnTarget();
}

class Pebble extends Projectile {
    @Override public String effectOnTarget() {
        return "annoyed";
    }
}

class Bullet extends Projectile {
    @Override public String effectOnTarget() {
        return "holed";
    }
}

class NuclearMissle extends Projectile {
    @Override public String effectOnTarget() {
        return "obliterated";
    }
}

class GunIsEmptyException extends Exception {
    private static final long serialVersionUID = 4574971294051632635L;
}

Beautiful way to remove GET-variables with PHP?

Couldn't you use the server variables to do this?

Or would this work?:

unset($_GET['page']);
$url = $_SERVER['SCRIPT_NAME'] ."?".http_build_query($_GET);

Just a thought.

How to install packages offline?

As a continues to @chaokunyang answer, I want to put here the script I write that does the work:

  1. Write a "requirements.txt" file that specifies the libraries you want to pack.
  2. Create a tar file that contains all your libraries (see the Packer script).
  3. Put the created tar file in the target machine and untar it.
  4. run the Installer script (which is also packed into the tar file).

"requirements.txt" file

docker==4.4.0

Packer side: file name: "create-offline-python3.6-dependencies-repository.sh"

#!/usr/bin/env bash

# This script follows the steps described in this link:
# https://stackoverflow.com/a/51646354/8808983

LIBRARIES_DIR="python3.6-wheelhouse"

if [ -d ${LIBRARIES_DIR} ]; then
    rm -rf ${LIBRARIES_DIR}/*
else
    mkdir ${LIBRARIES_DIR}
fi

pip download -r requirements.txt -d ${LIBRARIES_DIR}

files_to_add=("requirements.txt" "install-python-libraries-offline.sh")

for file in "${files_to_add[@]}"; do
    echo "Adding file ${file}"
    cp "$file" ${LIBRARIES_DIR}
done

tar -cf ${LIBRARIES_DIR}.tar ${LIBRARIES_DIR}

Installer side: file name: "install-python-libraries-offline.sh"

#!/usr/bin/env bash

# This script follows the steps described in this link:
# https://stackoverflow.com/a/51646354/8808983

# This file should run during the installation process from inside the libraries directory, after it was untared:
# pythonX-wheelhouse.tar -> untar -> pythonX-wheelhouse
# |
# |--requirements.txt
# |--install-python-libraries-offline.sh


pip3 install -r requirements.txt --no-index --find-links .

How to pass object from one component to another in Angular 2?

you could also store your data in an service with an setter and get it over a getter

import { Injectable } from '@angular/core';

@Injectable()
export class StorageService {

    public scope: Array<any> | boolean = false;

    constructor() {
    }

    public getScope(): Array<any> | boolean {
        return this.scope;
    }

    public setScope(scope: any): void {
        this.scope = scope;
    }
}

Pyspark: Filter dataframe based on multiple conditions

faster way (without pyspark.sql.functions)

    df.filter((df.d<5)&((df.col1 != df.col3) |
                    (df.col2 != df.col4) & 
                    (df.col1 ==df.col3)))\
    .show()

Declaring an unsigned int in Java

Whether a value in an int is signed or unsigned depends on how the bits are interpreted - Java interprets bits as a signed value (it doesn't have unsigned primitives).

If you have an int that you want to interpret as an unsigned value (e.g. you read an int from a DataInputStream that you know should be interpreted as an unsigned value) then you can do the following trick.

int fourBytesIJustRead = someObject.getInt();
long unsignedValue = fourBytesIJustRead & 0xffffffffL;

Note, that it is important that the hex literal is a long literal, not an int literal - hence the 'L' at the end.

How to run html file using node js

Move your HTML file in a folder "www". Create a file "server.js" with code :

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

app.use(express.static(__dirname + '/www'));

app.listen('3000');
console.log('working on 3000');

After creation of file, run the command "node server.js"

Why is the Visual Studio 2015/2017/2019 Test Runner not discovering my xUnit v2 tests

None of the above solutions worked for me (dotnetcore 1.1, VS2017). Here's what fixed it:

  1. Add NuGet Package Microsoft.TestPlatform.TestHost
  2. Add NuGet Package Microsoft.NET.Test.Sdk

Those are in addition to these packages I installed prior:

  • xunit (2.3.0-beta1-build3642)
  • xunit.runner.visualstudio (2.3.0-beta1-build1309)

python: how to identify if a variable is an array or a scalar

preds_test[0] is of shape (128,128,1) Lets check its data type using isinstance() function isinstance takes 2 arguments. 1st argument is data 2nd argument is data type isinstance(preds_test[0], np.ndarray) gives Output as True. It means preds_test[0] is an array.

ProcessStartInfo hanging on "WaitForExit"? Why?

Rob answered it and saved me few more hours of trials. Read the output/error buffer before waiting:

// Read the output stream first and then wait.
string output = p.StandardOutput.ReadToEnd();
p.WaitForExit();

Angular - ng: command not found

For Linux user

$ alias ng="/home/jones/node_modules/@angular/cli/bin/ng"

then check angular/cli version

ng --version

enter image description here

How to encode URL parameters?

Using new ES6 Object.entries(), it makes for a fun little nested map/join:

_x000D_
_x000D_
const encodeGetParams = p => _x000D_
  Object.entries(p).map(kv => kv.map(encodeURIComponent).join("=")).join("&");_x000D_
_x000D_
const params = {_x000D_
  user: "María Rodríguez",_x000D_
  awesome: true,_x000D_
  awesomeness: 64,_x000D_
  "ZOMG+&=*(": "*^%*GMOZ"_x000D_
};_x000D_
_x000D_
console.log("https://example.com/endpoint?" + encodeGetParams(params))
_x000D_
_x000D_
_x000D_

How to check all checkboxes using jQuery?

$('#checkAll').on('change', function(){
    if($(this).attr('checked')){
        $('input[type=checkbox]').attr('checked',true);
    }
    else{
        $('input[type=checkbox]').removeAttr('checked');
    }
});

How do I clear/delete the current line in terminal?

I have the complete shortcuts list:

  1. Ctrl+a Move cursor to start of line
  2. Ctrl+e Move cursor to end of line
  3. Ctrl+b Move back one character
  4. Alt+b Move back one word
  5. Ctrl+f Move forward one character
  6. Alt+f Move forward one word
  7. Ctrl+d Delete current character
  8. Ctrl+w Cut the last word
  9. Ctrl+k Cut everything after the cursor
  10. Alt+d Cut word after the cursor
  11. Alt+w Cut word before the cursor
  12. Ctrl+y Paste the last deleted command
  13. Ctrl+_ Undo
  14. Ctrl+u Cut everything before the cursor
  15. Ctrl+xx Toggle between first and current position
  16. Ctrl+l Clear the terminal
  17. Ctrl+c Cancel the command
  18. Ctrl+r Search command in history - type the search term
  19. Ctrl+j End the search at current history entry
  20. Ctrl+g Cancel the search and restore original line
  21. Ctrl+n Next command from the History
  22. Ctrl+p previous command from the History

jQuery: How can I create a simple overlay?

Here is a simple javascript only solution

function displayOverlay(text) {
    $("<table id='overlay'><tbody><tr><td>" + text + "</td></tr></tbody></table>").css({
        "position": "fixed",
        "top": 0,
        "left": 0,
        "width": "100%",
        "height": "100%",
        "background-color": "rgba(0,0,0,.5)",
        "z-index": 10000,
        "vertical-align": "middle",
        "text-align": "center",
        "color": "#fff",
        "font-size": "30px",
        "font-weight": "bold",
        "cursor": "wait"
    }).appendTo("body");
}

function removeOverlay() {
    $("#overlay").remove();
}

Demo:

http://jsfiddle.net/UziTech/9g0pko97/

Gist:

https://gist.github.com/UziTech/7edcaef02afa9734e8f2

What does "collect2: error: ld returned 1 exit status" mean?

Try running task manager to determine if your program is still running.

If it is running then stop it and run it again. the [Error] ld returned 1 exit status will not come back

Windows 7: unable to register DLL - Error Code:0X80004005

Use following command should work on windows 7. don't forget to enclose the dll name with full path in double quotations.

C:\Windows\SysWOW64>regsvr32 "c:\dll.name" 

Check if all values in list are greater than a certain number

 a = [[a, 2], [b, 3], [c, 4], [d, 5], [a, 1], [b, 6], [e, 7], [h, 8]]

I need this from above one

 a = [[a, 3], [b, 9], [c, 4], [d, 5], [e, 7], [h, 8]]
a.append([0, 0])
for i in range(len(a)):
     for j in range(i + 1, len(a) - 1):
            if a[i][0] == a[j][0]:
                    a[i][1] += a[j][1]
                    del a[j]
a.pop()
        

Update cordova plugins in one command

This is my Windows Batch version for update all plugins in one command

How to use:

From command line, in the same folder of project, run

c:\> batchNameFile

or

c:\> batchNameFile autoupdate

Where "batchNameFile" is the name of .BAT file, with the script below.

For only test ( first exmple ) or to force every update avaiable ( 2nd example )

@echo off

cls

set pluginListFile=update.plugin.list

if exist %pluginListFile% del %pluginListFile%

Echo "Reading installed Plugins"
Call cordova plugins > %pluginListFile%
echo.

for /F "tokens=1,2 delims= " %%a in ( %pluginListFile% ) do (
   Echo "Checking online version for %%a"

   for /F "delims=" %%I in ( 'npm info %%a version' ) do (
     Echo "Local : %%b"
     Echo "Online: %%I"
     if %%b LSS %%I Call :toUpdate %%a %~1
     :cont
     echo.
   )
)

if exist %pluginListFile% del %pluginListFile%

Exit /B

:toUpdate
Echo "Need Update !"
if '%~2' == 'autoupdate' Call :DoUpdate %~1
goto cont

:DoUpdate
Echo "Removing Plugin"
Call cordova plugin rm %~1
Echo "Adding Plugin"
Call cordova plugin add %~1
goto cont

This batch was only tested in Windows 10