Programs & Examples On #Store

A store is a data repository of a set of integrated objects. These objects are modeled using classes defined in database schemas. Data store includes not only data repositories like databases, it is a more general concept that includes also flat files that can store data.

How to reset the state of a Redux store?

One thing the solution in the accepted answer doesn't do is clear the cache for parameterized selectors. If you have a selector like this:

export const selectCounter1 = (state: State) => state.counter1;
export const selectCounter2 = (state: State) => state.counter2;
export const selectTotal = createSelector(
  selectCounter1,
  selectCounter2,
  (counter1, counter2) => counter1 + counter2
);

Then you would have to release them on logout like this:

selectTotal.release();

Otherwise the memoized value for the last call of the selector and the values of the last parameters will still be in memory.

Code samples are from the ngrx docs.

C# winforms combobox dynamic autocomplete

In previous replies are drawbacks. Offers its own version with the selection in the drop down list the desired item:

    private ConnectSqlForm()
    {
        InitializeComponent();
        cmbDatabases.TextChanged += UpdateAutoCompleteComboBox;
        cmbDatabases.KeyDown += AutoCompleteComboBoxKeyPress;
    }

    private void UpdateAutoCompleteComboBox(object sender, EventArgs e)
    {
        var comboBox = sender as ComboBox;
        if(comboBox == null)
        return;
        string txt = comboBox.Text;
        string foundItem = String.Empty;
        foreach(string item in comboBox.Items)
            if (!String.IsNullOrEmpty(txt) && item.ToLower().StartsWith(txt.ToLower()))
            {
                foundItem = item;
                break;
            }

        if (!String.IsNullOrEmpty(foundItem))
        {
            if (String.IsNullOrEmpty(txt) || !txt.Equals(foundItem))
            {
                comboBox.TextChanged -= UpdateAutoCompleteComboBox;
                comboBox.Text = foundItem;
                comboBox.DroppedDown = true;
                Cursor.Current = Cursors.Default;
                comboBox.TextChanged += UpdateAutoCompleteComboBox;
            }

            comboBox.SelectionStart = txt.Length;
            comboBox.SelectionLength = foundItem.Length - txt.Length;
        }
        else
            comboBox.DroppedDown = false;
    }

    private void AutoCompleteComboBoxKeyPress(object sender, KeyEventArgs e)
    {
        var comboBox = sender as ComboBox;
        if (comboBox != null && comboBox.DroppedDown)
        {
            switch (e.KeyCode)
            {
                case Keys.Back:
                    int sStart = comboBox.SelectionStart;
                    if (sStart > 0)
                    {
                        sStart--;
                        comboBox.Text = sStart == 0 ? "" : comboBox.Text.Substring(0, sStart);
                    }
                    e.SuppressKeyPress = true;
                    break;
            }

        }
    }

How does functools partial do what it does?

short answer, partial gives default values to the parameters of a function that would otherwise not have default values.

from functools import partial

def foo(a,b):
    return a+b

bar = partial(foo, a=1) # equivalent to: foo(a=1, b)
bar(b=10)
#11 = 1+10
bar(a=101, b=10)
#111=101+10

Change WPF controls from a non-main thread using Dispatcher.Invoke

The first thing is to understand that, the Dispatcher is not designed to run long blocking operation (such as retrieving data from a WebServer...). You can use the Dispatcher when you want to run an operation that will be executed on the UI thread (such as updating the value of a progress bar).

What you can do is to retrieve your data in a background worker and use the ReportProgress method to propagate changes in the UI thread.

If you really need to use the Dispatcher directly, it's pretty simple:

Application.Current.Dispatcher.BeginInvoke(
  DispatcherPriority.Background,
  new Action(() => this.progressBar.Value = 50));

Angular 2: How to style host element of the component?

There was a bug, but it was fixed in the meantime. :host { } works fine now.

Also supported are

  • :host(selector) { ... } for selector to match attributes, classes, ... on the host element
  • :host-context(selector) { ... } for selector to match elements, classes, ...on parent components

  • selector /deep/ selector (alias selector >>> selector doesn't work with SASS) for styles to match across element boundaries

    • UPDATE: SASS is deprecating /deep/.
      Angular (TS and Dart) added ::ng-deep as a replacement that's also compatible with SASS.

    • UPDATE2: ::slotted ::slotted is now supported by all new browsers and can be used with `ViewEncapsulation.ShadowDom
      https://developer.mozilla.org/en-US/docs/Web/CSS/::slotted

See also Load external css style into Angular 2 Component

/deep/ and >>> are not affected by the same selector combinators that in Chrome which are deprecated.
Angular emulates (rewrites) them, and therefore doesn't depend on browsers supporting them.

This is also why /deep/ and >>> don't work with ViewEncapsulation.Native which enables native shadow DOM and depends on browser support.

$(document).ready not Working

One possibility, take a look:

<script language="javascript" type="text/javascript" src="./jquery-3.1.1.slim.min.js" />

vs

<script language="javascript" type="text/javascript" src="./jquery-3.1.1.slim.min.js"></script>

The first method is actually wrong, however the browser does not complain at all. You need to be sure that you are indeed closing the javascript tag in the proper way.

What is the optimal algorithm for the game 2048?

I wrote a 2048 solver in Haskell, mainly because I'm learning this language right now.

My implementation of the game slightly differs from the actual game, in that a new tile is always a '2' (rather than 90% 2 and 10% 4). And that the new tile is not random, but always the first available one from the top left. This variant is also known as Det 2048.

As a consequence, this solver is deterministic.

I used an exhaustive algorithm that favours empty tiles. It performs pretty quickly for depth 1-4, but on depth 5 it gets rather slow at a around 1 second per move.

Below is the code implementing the solving algorithm. The grid is represented as a 16-length array of Integers. And scoring is done simply by counting the number of empty squares.

bestMove :: Int -> [Int] -> Int
bestMove depth grid = maxTuple [ (gridValue depth (takeTurn x grid), x) | x <- [0..3], takeTurn x grid /= [] ]

gridValue :: Int -> [Int] -> Int
gridValue _ [] = -1
gridValue 0 grid = length $ filter (==0) grid  -- <= SCORING
gridValue depth grid = maxInList [ gridValue (depth-1) (takeTurn x grid) | x <- [0..3] ]

I thinks it's quite successful for its simplicity. The result it reaches when starting with an empty grid and solving at depth 5 is:

Move 4006
[2,64,16,4]
[16,4096,128,512]
[2048,64,1024,16]
[2,4,16,2]

Game Over

Source code can be found here: https://github.com/popovitsj/2048-haskell

How do I test if a recordSet is empty? isNull?

If Not temp_rst1 Is Nothing Then ...

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

The problem

The problem is in the network layer. Here are the status codes explained:

  • Connection refused: The peer is not listening on the respective network port you're trying to connect to. This usually means that either a firewall is actively denying the connection or the respective service is not started on the other site or is overloaded.

  • Connection timed out: During the attempt to establish the TCP connection, no response came from the other side within a given time limit. In the context of urllib this may also mean that the HTTP response did not arrive in time. This is sometimes also caused by firewalls, sometimes by network congestion or heavy load on the remote (or even local) site.

In context

That said, it is probably not a problem in your script, but on the remote site. If it's occuring occasionally, it indicates that the other site has load problems or the network path to the other site is unreliable.

Also, as it is a problem with the network, you cannot tell what happened on the other side. It is possible that the packets travel fine in the one direction but get dropped (or misrouted) in the other.

It is also not a (direct) DNS problem, that would cause another error (Name or service not known or something similar). It could however be the case that the DNS is configured to return different IP addresses on each request, which would connect you (DNS caching left aside) to different addresses hosts on each connection attempt. It could in turn be the case that some of these hosts are misconfigured or overloaded and thus cause the aforementioned problems.

Debugging this

As suggested in the another answer, using a packet analyzer can help to debug the issue. You won't see much however except the packets reflecting exactly what the error message says.

To rule out network congestion as a problem you could use a tool like mtr or traceroute or even ping to see if packets get lost to the remote site. Note that, if you see loss in mtr (and any traceroute tool for that matter), you must always consider the first host where loss occurs (in the route from yours to remote) as the one dropping packets, due to the way ICMP works. If the packets get lost only at the last hop over a long time (say, 100 packets), that host definetly has an issue. If you see that this behaviour is persistent (over several days), you might want to contact the administrator.

Loss in a middle of the route usually corresponds to network congestion (possibly due to maintenance), and there's nothing you could do about it (except whining at the ISP about missing redundance).

If network congestion is not a problem (i.e. not more than, say, 5% of the packets get lost), you should contact the remote server administrator to figure out what's wrong. He may be able to see relevant infos in system logs. Running a packet analyzer on the remote site might also be more revealing than on the local site. Checking whether the port is open using netstat -tlp is definetly recommended then.

How to copy selected files from Android with adb pull

As to the short script, the following runs on my Linux host

#!/bin/bash
HOST_DIR=<pull-to>
DEVICE_DIR=/sdcard/<pull-from>
EXTENSION="\.jpg"

while read MYFILE ; do
    adb pull "$DEVICE_DIR/$MYFILE" "$HOST_DIR/$MYFILE"
done < $(adb shell ls -1 "$DEVICE_DIR" | grep "$EXTENSION")

"ls minus one" lets "ls" show one file per line, and the quotation marks allow spaces in the filename.

Get the Selected value from the Drop down box in PHP

You need to set a name on the <select> tag like so:

<select name="select_catalog" id="select_catalog">

You can get it in php with this:

$_POST['select_catalog'];

SQL How to remove duplicates within select query?

here is the solution for your query returning only one row for each date in that table here in the solution 'tony' will occur twice as two different start dates are there for it

SELECT * FROM 
(
    SELECT T1.*, ROW_NUMBER() OVER(PARTITION BY TRUNC(START_DATE),OWNER_NAME ORDER BY 1,2 DESC )  RNM
    FROM TABLE T1
)
WHERE RNM=1

Is `shouldOverrideUrlLoading` really deprecated? What can I use instead?

Documenting in detail for future readers:

The short answer is you need to override both the methods. The shouldOverrideUrlLoading(WebView view, String url) method is deprecated in API 24 and the shouldOverrideUrlLoading(WebView view, WebResourceRequest request) method is added in API 24. If you are targeting older versions of android, you need the former method, and if you are targeting 24 (or later, if someone is reading this in distant future) it's advisable to override the latter method as well.

The below is the skeleton on how you would accomplish this:

class CustomWebViewClient extends WebViewClient {

    @SuppressWarnings("deprecation")
    @Override
    public boolean shouldOverrideUrlLoading(WebView view, String url) {
        final Uri uri = Uri.parse(url);
        return handleUri(uri);
    }

    @TargetApi(Build.VERSION_CODES.N)
    @Override
    public boolean shouldOverrideUrlLoading(WebView view, WebResourceRequest request) {
        final Uri uri = request.getUrl();
        return handleUri(uri);
    }

    private boolean handleUri(final Uri uri) {
        Log.i(TAG, "Uri =" + uri);
        final String host = uri.getHost();
        final String scheme = uri.getScheme();
        // Based on some condition you need to determine if you are going to load the url 
        // in your web view itself or in a browser. 
        // You can use `host` or `scheme` or any part of the `uri` to decide.
        if (/* any condition */) {
            // Returning false means that you are going to load this url in the webView itself
            return false;
        } else {
            // Returning true means that you need to handle what to do with the url
            // e.g. open web page in a Browser
            final Intent intent = new Intent(Intent.ACTION_VIEW, uri);
            startActivity(intent);
            return true;
        }
    }
}

Just like shouldOverrideUrlLoading, you can come up with a similar approach for shouldInterceptRequest method.

How to get the CUDA version?

One can get the cuda version by typing the following in the terminal:

$ nvcc -V

# below is the result
nvcc: NVIDIA (R) Cuda compiler driver
Copyright (c) 2005-2017 NVIDIA Corporation
Built on Fri_Nov__3_21:07:56_CDT_2017
Cuda compilation tools, release 9.1, V9.1.85

Alternatively, one can manually check for the version by first finding out the installation directory using:

$ whereis -b cuda         
cuda: /usr/local/cuda

And then cd into that directory and check for the CUDA version.

Creating a new DOM element from an HTML string using built-in DOM methods or Prototype

Use insertAdjacentHTML(). It works with all current browsers, even with IE11.

_x000D_
_x000D_
var mylist = document.getElementById('mylist');_x000D_
mylist.insertAdjacentHTML('beforeend', '<li>third</li>');
_x000D_
<ul id="mylist">_x000D_
 <li>first</li>_x000D_
 <li>second</li>_x000D_
</ul>
_x000D_
_x000D_
_x000D_

macro for Hide rows in excel 2010

You almost got it. You are hiding the rows within the active sheet. which is okay. But a better way would be add where it is.

Rows("52:55").EntireRow.Hidden = False

becomes

activesheet.Rows("52:55").EntireRow.Hidden = False

i've had weird things happen without it. As for making it automatic. You need to use the worksheet_change event within the sheet's macro in the VBA editor (not modules, double click the sheet1 to the far left of the editor.) Within that sheet, use the drop down menu just above the editor itself (there should be 2 listboxes). The listbox to the left will have the events you are looking for. After that just throw in the macro. It should look like the below code,

Private Sub Worksheet_Change(ByVal Target As Range)
test1
end Sub

That's it. Anytime you change something, it will run the macro test1.

How are ssl certificates verified?

Here is a very simplified explanation:

  1. Your web browser downloads the web server's certificate, which contains the public key of the web server. This certificate is signed with the private key of a trusted certificate authority.

  2. Your web browser comes installed with the public keys of all of the major certificate authorities. It uses this public key to verify that the web server's certificate was indeed signed by the trusted certificate authority.

  3. The certificate contains the domain name and/or ip address of the web server. Your web browser confirms with the certificate authority that the address listed in the certificate is the one to which it has an open connection.

  4. Your web browser generates a shared symmetric key which will be used to encrypt the HTTP traffic on this connection; this is much more efficient than using public/private key encryption for everything. Your browser encrypts the symmetric key with the public key of the web server then sends it back, thus ensuring that only the web server can decrypt it, since only the web server has its private key.

Note that the certificate authority (CA) is essential to preventing man-in-the-middle attacks. However, even an unsigned certificate will prevent someone from passively listening in on your encrypted traffic, since they have no way to gain access to your shared symmetric key.

Oracle SQL Developer - tables cannot be seen

I had this problem on my Mac. Fixed it by uninstalling it AND removing the /Users/aa77686/.sqldeveloper folder. Uninstalling without deleting that folder did not fix it.
Then redownloaded and reinstalled.
Started it up, added connections and it worked fine.
Quit it, restarted it several times and it shows the tables, etc. correctly each time so far.

XSLT equivalent for JSON

There is now! I recently created a library, json-transforms, exactly for this purpose:

https://github.com/ColinEberhardt/json-transforms

It uses a combination of JSPath, a DSL modelled on XPath, and a recursive pattern matching approach, inspired directly by XSLT.

Here's a quick example. Given the following JSON object:

const json = {
  "automobiles": [
    { "maker": "Nissan", "model": "Teana", "year": 2011 },
    { "maker": "Honda", "model": "Jazz", "year": 2010 },
    { "maker": "Honda", "model": "Civic", "year": 2007 },
    { "maker": "Toyota", "model": "Yaris", "year": 2008 },
    { "maker": "Honda", "model": "Accord", "year": 2011 }
  ]
};

Here's a transformation:

const jsont = require('json-transforms');
const rules = [
  jsont.pathRule(
    '.automobiles{.maker === "Honda"}', d => ({
      Honda: d.runner()
    })
  ),
  jsont.pathRule(
    '.{.maker}', d => ({
      model: d.match.model,
      year: d.match.year
    })
  ),
  jsont.identity
];

const transformed  = jsont.transform(json, rules);

Which output the following:

{
  "Honda": [
    { "model": "Jazz", "year": 2010 },
    { "model": "Civic", "year": 2007 },
    { "model": "Accord", "year": 2011 }
  ]
}

This transform is composed of three rules. The first matches any automobile which is made by Honda, emitting an object with a Honda property, then recursively matching. The second rule matches any object with a maker property, outputting the model and year properties. The final is the identity transform that recursively matches.

How to update a value in a json file and save it through node.js

Save data after task completion

fs.readFile("./sample.json", 'utf8', function readFileCallback(err, data) {
        if (err) {
          console.log(err);
        } else {
          fs.writeFile("./sample.json", JSON.stringify(result), 'utf8', err => {
            if (err) throw err;
            console.log('File has been saved!');
          });
        }
      });

Insert ellipsis (...) into HTML tag if content too wide

There's actually a pretty straightforward way to do this in CSS exploiting the fact that IE extends this with non-standards and FF supports :after

You can also do this in JS if you wish by inspecting the scrollWidth of the target and comparing it to it's parents width, but imho this is less robust.

Edit: this is apparently more developed than I thought. CSS3 support may soon exist, and some imperfect extensions are available for you to try.

That last one is good reading.

How to insert new row to database with AUTO_INCREMENT column without specifying column names?

Even better, use DEFAULT instead of NULL. You want to store the default value, not a NULL that might trigger a default value.

But you'd better name all columns, with a piece of SQL you can create all the INSERT, UPDATE and DELETE's you need. Just check the information_schema and construct the queries you need. There is no need to do it all by hand, SQL can help you out.

jQuery UI Dialog Box - does not open after being closed

I use the dialog as an dialog file browser and uploader then I rewrite the code like this

var dialog1 = $("#dialog").dialog({ 
              autoOpen: false, 
              height: 480, 
              width: 640 
}); 
$('#tikla').click(function() {  
    dialog1.load('./browser.php').dialog('open');
});   

everything seems to work great.

Most efficient way to remove special characters from string

I agree with this code sample. The only different it I make it into Extension Method of string type. So that you can use it in a very simple line or code:

string test = "abc@#$123";
test.RemoveSpecialCharacters();

Thank to Guffa for your experiment.

public static class MethodExtensionHelper
    {
    public static string RemoveSpecialCharacters(this string str)
        {
            StringBuilder sb = new StringBuilder();
            foreach (char c in str)
            {
                if ((c >= '0' && c <= '9') || (c >= 'A' && c <= 'Z') || (c >= 'a' && c <= 'z') || c == '_')
                {
                    sb.Append(c);
                }
            }
            return sb.ToString();
        }
}

Mysql password expired. Can't connect

Just download MySQL workbench to log in. It will prompt you to change the password immediately and automatically.

How do I use HTML as the view engine in Express?

to server html pages through routing, I have done this.

var hbs = require('express-hbs');
app.engine('hbs', hbs.express4({
  partialsDir: __dirname + '/views/partials'
}));
app.set('views', __dirname + '/views');
app.set('view engine', 'hbs');

and renamed my .html files to .hbs files - handlebars support plain html

How to add/subtract dates with JavaScript?

The way I like, is if you have a date object you can subtract another date object from it to get the difference. Date objects are based on milliseconds from a certain date.

var date1 = new Date(2015, 02, 18); // "18/03/2015", month is 0-index
var date2 = new Date(2015, 02, 20); // "20/03/2015"

var msDiff = date2 - date1; // 172800000, this is time in milliseconds
var daysDiff = msDiff / 1000 / 60 / 60 / 24; // 2 days

So this is how you subtract dates. Now if you want to add them? date1 + date2 gives an error.. But if I want to get the time in ms I can use:

var dateMs = date1 - 0;
// say I want to add 5 days I can use
var days = 5;
var msToAdd = days * 24 * 60 * 60 * 1000; 
var newDate = new Date(dateMs + msToAdd);

By subtracting 0 you turn the date object into the milliseconds format.

Getting cursor position in Python

You will not find such function in standard Python libraries, while this function is Windows specific. However if you use ActiveState Python, or just install win32api module to standard Python Windows installation you can use:

x, y = win32api.GetCursorPos()

How can I provide multiple conditions for data trigger in WPF?

THIS ANSWER IS FOR ANIMATIONS ONLY


If you wanna implement the AND logic, you should use MultiTrigger, here is an example:

Suppose we want to do some actions if the property Text="" (empty string) AND IsKeyboardFocused="False", then your code should look like the following:

<MultiTrigger>
    <MultiTrigger.Conditions>
        <Condition Property="Text" Value="" />
        <Condition Property="IsKeyboardFocused" Value="False" />
    </MultiTrigger.Conditions>
        <MultiTrigger.EnterActions>
            <!-- Your actions here -->
        </MultiTrigger.EnterActions>
</MultiTrigger>

If you wanna implement the OR logic, there are couple of ways, and it depends on what you try to do:

The first option is to use multiple Triggers.
So, suppose you wanna do something if either Text="" OR IsKeyboardFocused="False",
then your code should look something like this:

<Trigger Property="IsEnabled" Value="false">
    <Setter Property="Opacity" TargetName="border" Value="0.56"/>
</Trigger>
<Trigger Property="IsMouseOver" Value="true">
    <Setter Property="BorderBrush" TargetName="border" 
            Value="{StaticResource TextBox.MouseOver.Border}"/>
</Trigger>


But the problem in this is what will I do if i wanna do something if either Text ISN'T null OR IsKeyboard="True"? This can be achieved by the second approach:
Recall De Morgan's rule, that says !(!x && !y) = x || y.
So we'll use it to solve the previous problem, by writing a multi trigger that it's triggered when Text="" and IsKeyboard="True", and we'll do our actions in EXIT ACTIONS, like this:

<MultiTrigger>
    <MultiTrigger.Conditions>
        <Condition Property="Text" Value="" />
        <Condition Property="IsKeyboardFocused" Value="False" />
    </MultiTrigger.Conditions>
    <MultiTrigger.ExitActions>
        <!-- Do something here -->
    </MultiTrigger.ExitActions>
</MultiTrigger>

How to echo out the values of this array?

var_dump($value)

it solved my problem, hope yours too.

How to get files in a relative path in C#

Pretty straight forward, use relative path

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

Image size (Python, OpenCV)

from this tutorial: https://www.tutorialkart.com/opencv/python/opencv-python-get-image-size/

import cv2

# read image
img = cv2.imread('/home/ubuntu/Walnut.jpg', cv2.IMREAD_UNCHANGED)

# get dimensions of image
dimensions = img.shape

# height, width, number of channels in image

height = img.shape[0]
width = img.shape[1]
channels = img.shape[2]

from this other tutorial: https://www.pyimagesearch.com/2018/07/19/opencv-tutorial-a-guide-to-learn-opencv/

image = cv2.imread("jp.png")

(h, w, d) = image.shape

Please double check things before posting answers.

Connection failed: SQLState: '01000' SQL Server Error: 10061

Received SQLSTATE 01000 in the following error message below:

SQL Agent - Jobs Failed: The SQL Agent Job "LiteSpeed Backup Full" has failed with the message "The job failed. The Job was invoked by User X. The last step to run was step 1 (Step1). NOTE: Failed to notify via email. - Executed as user: X. LiteSpeed(R) for SQL Server Version 6.5.0.1460 Copyright 2011 Quest Software, Inc. [SQLSTATE 01000] (Message 1) LiteSpeed for SQL Server could not open backup file: (N:\BACKUP2\filename.BAK). The previous system message is the reason for the failure. [SQLSTATE 42000] (Error 60405). The step failed."

In my case this was related to permission on drive N following an SQL Server failover on an Active/Passive SQL cluster.

All SQL resources where failed over to the seconary resouce and back to the preferred node following maintenance. When the Quest LiteSpeed job then executed on the preferred node it was clear the previous permissions for SQL server user X had been lost on drive N and SQLSTATE 10100 was reported.

Simply added the permissions again to the backup destination drive and the issue was resolved.

Hope that helps someone.

Windows 2008 Enterprise

SQL Server 2008 Active/Passive cluster.

How to determine the IP address of a Solaris system

The following worked pretty well for me:

ping -s my_host_name

Get absolute path of initially run script

If you want to get current working directory use getcwd()

http://php.net/manual/en/function.getcwd.php

__FILE__ will return path with filename for example on XAMPP C:\xampp\htdocs\index.php instead of C:\xampp\htdocs\

How to add/update an attribute to an HTML element using JavaScript?

What seems easy is actually tricky if you want to be completely compatible.

var e = document.createElement('div');

Let's say you have an id of 'div1' to add.

e['id'] = 'div1';
e.id = 'div1';
e.attributes['id'] = 'div1';
e.createAttribute('id','div1')
These will all work except the last in IE 5.5 (which is ancient history at this point but still is XP's default with no updates).

But there are contingencies, of course. Will not work in IE prior to 8:e.attributes['style'] Will not error but won't actually set the class, it must be className:e['class'] .
However, if you're using attributes then this WILL work:e.attributes['class']

In summary, think of attributes as literal and object-oriented.

In literal, you just want it to spit out x='y' and not think about it. This is what attributes, setAttribute, createAttribute is for (except for IE's style exception). But because these are really objects things can get confused.

Since you are going to the trouble of properly creating a DOM element instead of jQuery innerHTML slop, I would treat it like one and stick with the e.className = 'fooClass' and e.id = 'fooID'. This is a design preference, but in this instance trying to treat is as anything other than an object works against you.

It will never backfire on you like the other methods might, just be aware of class being className and style being an object so it's style.width not style="width:50px". Also remember tagName but this is already set by createElement so you shouldn't need to worry about it.

This was longer than I wanted, but CSS manipulation in JS is tricky business.

Correct way to create rounded corners in Twitter Bootstrap

What you want is a Bootstrap panel. Just add the panel class, and your header will look uniform. You can also add classes panel panel-info, panel panel-success, etc. It works for pretty much any block element, and should work with <header>, but I expect it would be used mostly with <div>s.

Parsing JSON using Json.net

(This question came up high on a search engine result, but I ended up using a different approach. Adding an answer to this old question in case other people with similar questions read this)

You can solve this with Json.Net and make an extension method to handle the items you want to loop:

public static Tuple<string, int, int> ToTuple(this JToken token)
{
    var type = token["attributes"]["OBJECT_TYPE"].ToString();
    var x = token["position"]["x"].Value<int>();
    var y = token["position"]["y"].Value<int>();
    return new Tuple<string, int, int>(type, x, y);
}

And then access the data like this: (scenario: writing to console):

var tuples = JObject.Parse(myJsonString)["objects"].Select(item => item.ToTuple()).ToList();
tuples.ForEach(t => Console.WriteLine("{0}: ({1},{2})", t.Item1, t.Item2, t.Item3));

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

hdpi 480x800 px Samsung S2

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

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

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

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

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

Amazon Linux: apt-get: command not found

If you're using Amazon Linux it's CentOS-based, which is RedHat-based. RH-based installs use yum not apt-get. Something like yum search httpd should show you the available Apache packages - you likely want yum install httpd24.

Note: Amazon Linux 2 has diverged from CentOS since the writing of this answer, but still uses yum.

git push to specific branch

If your Local branch and remote branch is the same name then you can just do it:

git push origin branchName

When your local and remote branch name is different then you can just do it:

git push origin localBranchName:remoteBranchName

Fastest way to find second (third...) highest/lowest value in vector or column

dplyr has the function nth, where the first argument is the vector and the second is which place you want. This goes for repeating elements as well. For example:

x = c(1,2, 8, 16, 17, 20, 1, 20)

Finding the second largest value:

 nth(unique(x),length(unique(x))-1)

[1] 17

How can I get a resource "Folder" from inside my jar File?

Finally, I found the solution:

final String path = "sample/folder";
final File jarFile = new File(getClass().getProtectionDomain().getCodeSource().getLocation().getPath());

if(jarFile.isFile()) {  // Run with JAR file
    final JarFile jar = new JarFile(jarFile);
    final Enumeration<JarEntry> entries = jar.entries(); //gives ALL entries in jar
    while(entries.hasMoreElements()) {
        final String name = entries.nextElement().getName();
        if (name.startsWith(path + "/")) { //filter according to the path
            System.out.println(name);
        }
    }
    jar.close();
} else { // Run with IDE
    final URL url = Launcher.class.getResource("/" + path);
    if (url != null) {
        try {
            final File apps = new File(url.toURI());
            for (File app : apps.listFiles()) {
                System.out.println(app);
            }
        } catch (URISyntaxException ex) {
            // never happens
        }
    }
}

The second block just work when you run the application on IDE (not with jar file), You can remove it if you don't like that.

Add/delete row from a table

I would try formatting your table correctly first off like so:

I cannot help but thinking that formatting the table could at the very least not do any harm.

<table>
   <thead>
      <th>Header1</th>
      ......
   </thead>
   <tbody>
       <tr><td>Content1</td>....</tr>
       ......
   </tbody>
</table>

How to drop rows of Pandas DataFrame whose value in a certain column is NaN

Don't drop, just take the rows where EPS is not NA:

df = df[df['EPS'].notna()]

Unable to launch the IIS Express Web server, Failed to register URL, Access is denied

Got this error as well lately. Tried all the above fixes, but none worked.

To disable it, type services.msc in command prompt, then right click and disable Internet Connection Sharing. I edited the properties of it as well to disable at startup. Mine looks like so now: services capture screenshot.

How do I make a checkbox required on an ASP.NET form?

If you want a true validator that does not rely on jquery and handles server side validation as well ( and you should. server side validation is the most important part) then here is a control

public class RequiredCheckBoxValidator : System.Web.UI.WebControls.BaseValidator
{
    private System.Web.UI.WebControls.CheckBox _ctrlToValidate = null;
    protected System.Web.UI.WebControls.CheckBox CheckBoxToValidate
    {
        get
        {
            if (_ctrlToValidate == null)
                _ctrlToValidate = FindControl(this.ControlToValidate) as System.Web.UI.WebControls.CheckBox;

            return _ctrlToValidate;
        }
    }

    protected override bool ControlPropertiesValid()
    {
        if (this.ControlToValidate.Length == 0)
            throw new System.Web.HttpException(string.Format("The ControlToValidate property of '{0}' is required.", this.ID));

        if (this.CheckBoxToValidate == null)
            throw new System.Web.HttpException(string.Format("This control can only validate CheckBox."));

        return true;
    }

    protected override bool EvaluateIsValid()
    {
        return CheckBoxToValidate.Checked;
    }

    protected override void OnPreRender(EventArgs e)
    {
        base.OnPreRender(e);

        if (this.Visible && this.Enabled)
        {
            System.Web.UI.ClientScriptManager cs = this.Page.ClientScript;
            if (this.DetermineRenderUplevel() && this.EnableClientScript)
            {
                cs.RegisterExpandoAttribute(this.ClientID, "evaluationfunction", "cb_verify", false);
            }
            if (!this.Page.ClientScript.IsClientScriptBlockRegistered(this.GetType().FullName))
            {
                cs.RegisterClientScriptBlock(this.GetType(), this.GetType().FullName, GetClientSideScript());
            } 
        }
    }

    private string GetClientSideScript()
    {
        return @"<script language=""javascript"">function cb_verify(sender) {var cntrl = document.getElementById(sender.controltovalidate);return cntrl.checked;}</script>";
    }
}

How to implement static class member functions in *.cpp file?

helper.hxx

class helper
{
 public: 
   static void fn1 () 
   { /* defined in header itself */ }

   /* fn2 defined in src file helper.cxx */
   static void fn2(); 
};

helper.cxx

#include "helper.hxx"
void helper::fn2()
{
  /* fn2 defined in helper.cxx */
  /* do something */
}

A.cxx

#include "helper.hxx"
A::foo() {
  helper::fn1(); 
  helper::fn2();
}

To know more about how c++ handles static functions visit: Are static member functions in c++ copied in multiple translation units?

How to format x-axis time scale values in Chart.js v2

I had a different use case, I want different formats based how long between start and end time of data in graph. I found this to be simplest approach

    xAxes = {
        type: "time",
        time: {
            displayFormats: {
                hour: "hA"
            }
        },
        display: true,
        ticks: {
            reverse: true
        },
        gridLines: {display: false}
    }
    // if more than two days between start and end of data,  set format to show date,  not hrs
    if ((parseInt(Cookies.get("epoch_max")) - parseInt(Cookies.get("epoch_min"))) > (1000*60*60*24*2)) {
        xAxes.time.displayFormats.hour = "MMM D";
    }

How to test valid UUID/GUID?

Currently, UUID's are as specified in RFC4122. An often neglected edge case is the NIL UUID, noted here. The following regex takes this into account and will return a match for a NIL UUID. See below for a UUID which only accepts non-NIL UUIDs. Both of these solutions are for versions 1 to 5 (see the first character of the third block).

Therefore to validate a UUID...

/^[0-9a-f]{8}-[0-9a-f]{4}-[0-5][0-9a-f]{3}-[089ab][0-9a-f]{3}-[0-9a-f]{12}$/i

...ensures you have a canonically formatted UUID that is Version 1 through 5 and is the appropriate Variant as per RFC4122.

NOTE: Braces { and } are not canonical. They are an artifact of some systems and usages.

Easy to modify the above regex to meet the requirements of the original question.

HINT: regex group/captures

To avoid matching NIL UUID:

/^[0-9a-f]{8}-[0-9a-f]{4}-[1-5][0-9a-f]{3}-[89ab][0-9a-f]{3}-[0-9a-f]{12}$/i

How can I check if a directory exists in a Bash shell script?

You can use test -d (see man test).

-d file True if file exists and is a directory.

For example:

test -d "/etc" && echo Exists || echo Does not exist

Note: The test command is same as conditional expression [ (see: man [), so it's portable across shell scripts.

[ - This is a synonym for the test builtin, but the last argument must, be a literal ], to match the opening [.

For possible options or further help, check:

  • help [
  • help test
  • man test or man [

increase the java heap size permanently?

For Windows users, you can add a system environment variable named _JAVA_OPTIONS, and set the heap size values there. The JVM should be able to grab the virtual machine options from _JAVA_OPTIONS.

How do I remove the passphrase for the SSH key without having to create a new key?

You might want to add the following to your .bash_profile (or equivalent), which starts ssh-agent on login.

if [ -f ~/.agent.env ] ; then
    . ~/.agent.env > /dev/null
    if ! kill -0 $SSH_AGENT_PID > /dev/null 2>&1; then
        echo "Stale agent file found. Spawning new agent… "
        eval `ssh-agent | tee ~/.agent.env`
        ssh-add
    fi 
else
    echo "Starting ssh-agent"
    eval `ssh-agent | tee ~/.agent.env`
    ssh-add
fi

On some Linux distros (Ubuntu, Debian) you can use:

ssh-copy-id -i ~/.ssh/id_dsa.pub username@host

This will copy the generated id to a remote machine and add it to the remote keychain.

You can read more here and here.

How do I make Java register a string input with spaces?

Since it's a long time and people keep suggesting to use Scanner#nextLine(), there's another chance that Scanner can take spaces included in input.

Class Scanner

A Scanner breaks its input into tokens using a delimiter pattern, which by default matches whitespace.

You can use Scanner#useDelimiter() to change the delimiter of Scanner to another pattern such as a line feed or something else.

Scanner in = new Scanner(System.in);
in.useDelimiter("\n"); // use LF as the delimiter
String question;

System.out.println("Please input question:");
question = in.next();

// TODO do something with your input such as removing spaces...

if (question.equalsIgnoreCase("howdoyoulikeschool?") )
    /* it seems strings do not allow for spaces */
    System.out.println("CLOSED!!");
else
    System.out.println("Que?");

Error inflating class android.support.v7.widget.Toolbar?

Sorry Guys. I have solved this Issue long ago. I did a lot of changes. So I can't figure out which one does the trick.

  1. I have changed the id as suggested by Jared Burrows.

  2. Removed my support library and cleaned my project and Re added it.

  3. Go to File -> Invalidate Caches/Restart.

Hope it works.

This is how my code looks now

activity.xml

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

    <include
        android:id="@+id/toolbar_actionbar"
        layout="@layout/toolbar_default"
        android:layout_width="match_parent"
        android:layout_height="wrap_content"/>

    <android.support.v4.widget.DrawerLayout
        android:id="@+id/drawer"
        xmlns:android="http://schemas.android.com/apk/res/android"
        android:layout_width="match_parent"
        android:layout_height="match_parent"
        android:layout_below="@+id/toolbar_actionbar">

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

        <fragment
            android:id="@+id/fragment_drawer"
            android:name="com.arul.anahy.drawer.NavigationDrawerFragment"
            android:layout_width="@dimen/navigation_drawer_width"
            android:layout_height="match_parent"
            android:layout_gravity="start"
            app:layout="@layout/fragment_navigation_drawer"/>
    </android.support.v4.widget.DrawerLayout>
</RelativeLayout>

toolbar_default.xml

<?xml version="1.0" encoding="utf-8"?>
<android.support.v7.widget.Toolbar
    style="@style/ToolBarStyle"
    xmlns:android="http://schemas.android.com/apk/res/android"
    android:layout_width="match_parent"
    android:layout_height="wrap_content"
    android:background="?attr/colorPrimary"
    android:minHeight="@dimen/abc_action_bar_default_height_material"/>

ToolBarStyle

<style name="ToolBarStyle" parent="">
        <item name="popupTheme">@style/ThemeOverlay.AppCompat.Light</item>
        <item name="theme">@style/ThemeOverlay.AppCompat.Dark.ActionBar</item>
 </style>

CreateProcess error=2, The system cannot find the file specified

My recomendation is to keep the getRuntime().exec because exec uses the ProcessBuilder.

Try

 p=r.exec(new String[] {"winrar", "x", "h:\\myjar.jar", "*.*", "h:\\new"}, null, dir);

Get JSONArray without array name?

You don't need to call json.getJSONArray() at all, because the JSON you're working with already is an array. So, don't construct an instance of JSONObject; use a JSONArray. This should suffice:

// ...
JSONArray json = new JSONArray(result);
// ...

for(int i=0;i<json.length();i++){                        
    HashMap<String, String> map = new HashMap<String, String>();    
    JSONObject e = json.getJSONObject(i);

    map.put("id",  String.valueOf(i));
    map.put("name", "Earthquake name:" + e.getString("eqid"));
    map.put("magnitude", "Magnitude: " +  e.getString("magnitude"));
    mylist.add(map);            
}

You can't use exactly the same methods as in the tutorial, because the JSON you're dealing with needs to be parsed into a JSONArray at the root, not a JSONObject.

How to export html table to excel or pdf in php

Use a PHP Excel for generatingExcel file. You can find a good one called PHPExcel here: https://github.com/PHPOffice/PHPExcel

And for PDF generation use http://princexml.com/

Show compose SMS view in Android

You can omit tel number for letting user just choose from contacts, but inserting your sms text in the body. Code is for Xamarin Android:

    var uri = Uri.Parse("smsto:"); //append your number here for explicit nb
    var intent = new Intent(Intent.ActionSendto, uri);
    intent.PutExtra("sms_body", text);
    Context.StartActivity(intent);

where

Context is Xamarin.Essentials.Platform.CurrentActivity ?? Application.Context

stdlib and colored output in C

You can output special color control codes to get colored terminal output, here's a good resource on how to print colors.

For example:

printf("\033[22;34mHello, world!\033[0m");  // shows a blue hello world

EDIT: My original one used prompt color codes, which doesn't work :( This one does (I tested it).

Web Service vs WCF Service

The major difference is time-out, WCF Service has timed-out when there is no response, but web-service does not have this property.

"RangeError: Maximum call stack size exceeded" Why?

The answer with for is correct, but if you really want to use functional style avoiding for statement - you can use the following instead of your expression:

Array.from(Array(1000000), () => Math.random());

The Array.from() method creates a new Array instance from an array-like or iterable object. The second argument of this method is a map function to call on every element of the array.

Following the same idea you can rewrite it using ES2015 Spread operator:

[...Array(1000000)].map(() => Math.random())

In both examples you can get an index of the iteration if you need, for example:

[...Array(1000000)].map((_, i) => i + Math.random())

PHP Warning: POST Content-Length of 8978294 bytes exceeds the limit of 8388608 bytes in Unknown on line 0

1. First u will find the php.ini file.

u can find php.ini file from this path. C:\xampp\php or from xampp folder.

2. Now open php.ini file and change the following:

1. post-max-size (change 8M to 800M).

2. upload-max-filesize (change 2M to 2000M).

3. Now stop the Apache server and MySQL.

4. Now restart Apache server and MySQL.

It worked fine after that.

Enjoy ur working now :)

How do I get the result of a command in a variable in windows?

If you're looking for the solution provided in Using the result of a command as an argument in bash?

then here is the code:

@echo off
if not "%1"=="" goto get_basename_pwd
for /f "delims=X" %%i in ('cd') do call %0 %%i
for /f "delims=X" %%i in ('dir /o:d /b') do echo %%i>>%filename%.txt
goto end

:get_basename_pwd
set filename=%~n1

:end
  • This will call itself with the result of the CD command, same as pwd.
  • String extraction on parameters will return the filename/folder.
  • Get the contents of this folder and append to the filename.txt

[Credits]: Thanks to all the other answers and some digging on the Windows XP commands page.

Refresh DataGridView when updating data source

I ran into this myself. My recommendation: If you have ownership of the datasource, don't use a List. Use a BindingList. The BindingList has events that fire when items are added or changed, and the DataGridView will automatically update itself when these events are fired.

What is the difference between Swing and AWT?

AWT 1 . AWT occupies more memory space 2 . AWT is platform dependent 3 . AWT require javax.awt package

swings 1 . Swing occupies less memory space 2 . Swing component is platform independent 3 . Swing requires javax.swing package

Where can I download Spring Framework jars without using Maven?

Please edit to keep this list of mirrors current

I found this maven repo where you could download from directly a zip file containing all the jars you need.

Alternate solution: Maven

The solution I prefer is using Maven, it is easy and you don't have to download each jar alone. You can do it with the following steps:

  1. Create an empty folder anywhere with any name you prefer, for example spring-source

  2. Create a new file named pom.xml

  3. Copy the xml below into this file

  4. Open the spring-source folder in your console

  5. Run mvn install

  6. After download finished, you'll find spring jars in /spring-source/target/dependencies

    <project xmlns="http://maven.apache.org/POM/4.0.0" xmlns:xsi="http://www.w3.org/2001/XMLSchema-instance" xsi:schemaLocation="http://maven.apache.org/POM/4.0.0 http://maven.apache.org/xsd/maven-4.0.0.xsd">
      <modelVersion>4.0.0</modelVersion>
      <groupId>spring-source-download</groupId>
      <artifactId>SpringDependencies</artifactId>
      <version>1.0</version>
      <properties>
        <project.build.sourceEncoding>UTF-8</project.build.sourceEncoding>
      </properties>
      <dependencies>
        <dependency>
          <groupId>org.springframework</groupId>
          <artifactId>spring-context</artifactId>
          <version>3.2.4.RELEASE</version>
        </dependency>
      </dependencies>
      <build>
        <plugins>
          <plugin>
            <groupId>org.apache.maven.plugins</groupId>
            <artifactId>maven-dependency-plugin</artifactId>
            <version>2.8</version>
            <executions>
              <execution>
                <id>download-dependencies</id>
                <phase>generate-resources</phase>
                <goals>
                  <goal>copy-dependencies</goal>
                </goals>
                <configuration>
                  <outputDirectory>${project.build.directory}/dependencies</outputDirectory>
                </configuration>
              </execution>
            </executions>
          </plugin>
        </plugins>
      </build>
    </project>
    

Also, if you need to download any other spring project, just copy the dependency configuration from its corresponding web page.

For example, if you want to download Spring Web Flow jars, go to its web page, and add its dependency configuration to the pom.xml dependencies, then run mvn install again.

<dependency>
  <groupId>org.springframework.webflow</groupId>
  <artifactId>spring-webflow</artifactId>
  <version>2.3.2.RELEASE</version>
</dependency>

TypeError: $ is not a function WordPress

I was able to resolve this very easily my simply enqueuing jQuery wp_enqueue_script("jquery");

Exception of type 'System.OutOfMemoryException' was thrown. Why?

Where does it fail?

I agree that your issue is probably that your dataset of 600,000 rows is probably just too large. I see that you are then adding it to Session. If you are using Sql session state, it will have to serialize that data as well.

Even if you dispose of your objects properly, you will always have at least 2 copies of this dataset in memory if you run it twice, once in session, once in procedural code. This will never scale in a web application.

Do the math, 600,000 rows, at even 1-128 bit guid per row would yield 9.6 megabytes (600k * 128 / 8) of just data, not to mention the dataset overhead.

Trim down your results.

Does file_get_contents() have a timeout setting?

For me work when i change my php.ini in my host:

; Default timeout for socket based streams (seconds)
default_socket_timeout = 300

JPA - Returning an auto generated id after persist()

The ID is only guaranteed to be generated at flush time. Persisting an entity only makes it "attached" to the persistence context. So, either flush the entity manager explicitely:

em.persist(abc);
em.flush();
return abc.getId();

or return the entity itself rather than its ID. When the transaction ends, the flush will happen, and users of the entity outside of the transaction will thus see the generated ID in the entity.

@Override
public ABC addNewABC(ABC abc) {
    abcDao.insertABC(abc);
    return abc;
}

Download files from server php

Here is the code that will not download courpt files

$filename = "myfile.jpg";
$file = "/uploads/images/".$filename;

header('Content-type: application/octet-stream');
header("Content-Type: ".mime_content_type($file));
header("Content-Disposition: attachment; filename=".$filename);
while (ob_get_level()) {
    ob_end_clean();
}
readfile($file);

I have included mime_content_type which will return content type of file .

To prevent from corrupt file download i have added ob_get_level() and ob_end_clean();

WPF C# button style

<!--Customize button -->

<LinearGradientBrush x:Key="Buttongradient" StartPoint="0.500023,0.999996" EndPoint="0.500023,4.37507e-006">
    <GradientStop Color="#5e5e5e" Offset="1" />
    <GradientStop Color="#0b0b0b" Offset="0" />
</LinearGradientBrush> 

<Style x:Key="hhh" TargetType="{x:Type Button}">
    <Setter Property="Background" Value="{DynamicResource Buttongradient}"/>
    <Setter Property="Foreground" Value="White" />
    <Setter Property="FontSize" Value="15" />
    <Setter Property="SnapsToDevicePixels" Value="True" />
    <Setter Property="Template">
        <Setter.Value>
            <ControlTemplate TargetType="{x:Type Button}">
                <Border CornerRadius="4" Background="{TemplateBinding Background}" BorderBrush="Black" BorderThickness="0.5">
                    <Border.Effect>
                        <DropShadowEffect ShadowDepth="0" BlurRadius="2"></DropShadowEffect>
                    </Border.Effect>

                    <Grid>

                        <Path Width="9" Height="16.5" Stretch="Fill" Fill="#000"  HorizontalAlignment="Left" Margin="16.5,0,0,0" Data="F1 M 30.0833,22.1667L 50.6665,37.6043L 50.6665,38.7918L 30.0833,53.8333L 30.0833,22.1667 Z " Opacity="0.2">

                        </Path>
                        <Path x:Name="PathIcon" Width="8" Height="15"  Stretch="Fill" Fill="#4C87B3" HorizontalAlignment="Left" Margin="17,0,0,0" Data="F1 M 30.0833,22.1667L 50.6665,37.6043L 50.6665,38.7918L 30.0833,53.8333L 30.0833,22.1667 Z ">
                            <Path.Effect>
                                <DropShadowEffect ShadowDepth="0" BlurRadius="5"></DropShadowEffect>
                            </Path.Effect>
                        </Path>


                        <Line  HorizontalAlignment="Left" Margin="40,0,0,0" Name="line4" Stroke="Black" VerticalAlignment="Top" Width="2" Y1="0" Y2="640" Opacity="0.5" />
                        <ContentPresenter x:Name="MyContentPresenter" Content="{TemplateBinding Content}" HorizontalAlignment="Center" VerticalAlignment="Center" Margin="0,0,0,0" />
                    </Grid>
                </Border>

                <ControlTemplate.Triggers>
                    <Trigger Property="IsMouseOver" Value="True">
                        <Setter Property="Background" Value="#E59400" />
                        <Setter Property="Foreground" Value="White" />
                        <Setter TargetName="PathIcon" Property="Fill" Value="Black" />
                    </Trigger>

                    <Trigger Property="IsPressed" Value="True">
                        <Setter Property="Background" Value="OrangeRed" />
                        <Setter Property="Foreground" Value="White" />
                    </Trigger>
                </ControlTemplate.Triggers>
            </ControlTemplate>
        </Setter.Value>
    </Setter>
</Style>  

printf, wprintf, %s, %S, %ls, char* and wchar*: Errors not announced by a compiler warning?

For s: When used with printf functions, specifies a single-byte or multi-byte character string; when used with wprintf functions, specifies a wide-character string. Characters are displayed up to the first null character or until the precision value is reached.

For S: When used with printf functions, specifies a wide-character string; when used with wprintf functions, specifies a single-byte or multi-byte character string. Characters are displayed up to the first null character or until the precision value is reached.

In Unix-like platform, s and S have the same meaning as windows platform.

Reference: https://msdn.microsoft.com/en-us/library/hf4y5e3w.aspx

How do I remove all HTML tags from a string without knowing which tags are in it?

You can use the below code on your string and you will get the complete string without html part.

string title = "<b> Hulk Hogan's Celebrity Championship Wrestling &nbsp;&nbsp;&nbsp;<font color=\"#228b22\">[Proj # 206010]</font></b>&nbsp;&nbsp;&nbsp; (Reality Series, &nbsp;)".Replace("&nbsp;",string.Empty);            
        string s = Regex.Replace(title, "<.*?>", String.Empty);

How can I compare two strings in java and define which of them is smaller than the other alphabetically?

If you would like to ignore case you could use the following:

String s = "yip";
String best = "yodel";
int compare = s.compareToIgnoreCase(best);
if(compare < 0){
    //-1, --> s is less than best. ( s comes alphabetically first)
}
else if(compare > 0 ){
// best comes alphabetically first.
}
else{
    // strings are equal.
}

Declare and Initialize String Array in VBA

In the specific case of a String array you could initialize the array using the Split Function as it returns a String array rather than a Variant array:

Dim arrWsNames() As String
arrWsNames = Split("Value1,Value2,Value3", ",")

This allows you to avoid using the Variant data type and preserve the desired type for arrWsNames.

Initialise a list to a specific length in Python

If the "default value" you want is immutable, @eduffy's suggestion, e.g. [0]*10, is good enough.

But if you want, say, a list of ten dicts, do not use [{}]*10 -- that would give you a list with the same initially-empty dict ten times, not ten distinct ones. Rather, use [{} for i in range(10)] or similar constructs, to construct ten separate dicts to make up your list.

Intercept page exit event

Instead of an annoying confirmation popup, it would be nice to delay leaving just a bit (matter of milliseconds) to manage successfully posting the unsaved data to the server, which I managed for my site using writing dummy text to the console like this:

window.onbeforeunload=function(e){
  // only take action (iterate) if my SCHEDULED_REQUEST object contains data        
  for (var key in SCHEDULED_REQUEST){   
    postRequest(SCHEDULED_REQUEST); // post and empty SCHEDULED_REQUEST object
    for (var i=0;i<1000;i++){
      // do something unnoticable but time consuming like writing a lot to console
      console.log('buying some time to finish saving data'); 
    };
    break;
  };
}; // no return string --> user will leave as normal but data is send to server

Edit: See also Synchronous_AJAX and how to do that with jquery

Tracking the script execution time in PHP

As an alternative you can just put this line in your code blocks and check php logs, for really slow functions it's pretty useful:

trigger_error("Task done at ". strftime('%H:%m:%S', time()), E_USER_NOTICE); 

For serious debugging use XDebug + Cachegrind, see https://blog.nexcess.net/2011/01/29/diagnosing-slow-php-execution-with-xdebug-and-kcachegrind/

How do I enumerate the properties of a JavaScript object?

I think an example of the case that has caught me by surprise is relevant:

var myObject = { name: "Cody", status: "Surprised" };
for (var propertyName in myObject) {
  document.writeln( propertyName + " : " + myObject[propertyName] );
}

But to my surprise, the output is

name : Cody
status : Surprised
forEach : function (obj, callback) {
    for (prop in obj) {
        if (obj.hasOwnProperty(prop) && typeof obj[prop] !== "function") {
            callback(prop);
        }
    }
}

Why? Another script on the page has extended the Object prototype:

Object.prototype.forEach = function (obj, callback) {
  for ( prop in obj ) {
    if ( obj.hasOwnProperty( prop ) && typeof obj[prop] !== "function" ) {
      callback( prop );
    }
  }
};

How to change fonts in matplotlib (python)?

The Helvetica font does not come included with Windows, so to use it you must download it as a .ttf file. Then you can refer matplotlib to it like this (replace "crm10.ttf" with your file):

import os
from matplotlib import font_manager as fm, rcParams
import matplotlib.pyplot as plt

fig, ax = plt.subplots()

fpath = os.path.join(rcParams["datapath"], "fonts/ttf/cmr10.ttf")
prop = fm.FontProperties(fname=fpath)
fname = os.path.split(fpath)[1]
ax.set_title('This is a special font: {}'.format(fname), fontproperties=prop)
ax.set_xlabel('This is the default font')

plt.show()

print(fpath) will show you where you should put the .ttf.

You can see the output here: https://matplotlib.org/gallery/api/font_file.html

Algorithm to find all Latitude Longitude locations within a certain distance from a given Lat Lng location

you may check this equation i think it will help

SELECT id, ( 3959 * acos( cos( radians(37) ) * cos( radians( lat ) ) * cos( radians( lng ) - radians(-122) ) + sin( radians(37) ) * sin( radians( lat ) ) ) ) AS distance FROM markers HAVING distance < 25 ORDER BY distance LIMIT 0 , 20;

isPrime Function for Python Language

(https://www.youtube.com/watch?v=Vxw1b8f_yts&t=3384s) Avinash Jain

for i in range(2,5003):
    j = 2
    c = 0
    while j < i:
        if i % j == 0:
            c = 1
            j = j + 1
        else:
            j = j + 1
    if c == 0:
        print(str(i) + ' is a prime number')
    else:
        c = 0

ClassNotFoundException: org.slf4j.LoggerFactory

You'll need to download SLF4J's jars from the official site as either a zip (v1.7.4) or tar.gz (v1.7.4)

The download contains multiple jars based on how you want to use SLF4J. If you're simply trying to resolve the requirement of some other library (GWT, I assume) and don't really care about using SLF4J correctly, then I would probably pick the slf4j-api-1.7.4.jar since the Simple jar suggested by another answer does not contain, to my knowledge, the specific class you're looking for.

Change Default branch in gitlab

In 8.0+ it looks like this was moved into the project. If you open your project and go to the gear icon on the right, then "Edit Project" you can set the default branch for the project.

How to connect to Oracle 11g database remotely

First. It is necessary add static IP address for Computer A AND B. For example in my case Computer A (172.20.14.13) and B (172.20.14.78).

Second. In Computer A with Net Manager add for Listener new address (172.20.14.13) or manually add new record in listener.ora

# listener.ora Network Configuration File: E:\app\user\product\11.2.0\dbhome_1\NETWORK\ADMIN\listener.ora
# Generated by Oracle configuration tools.

SID_LIST_LISTENER =
  (SID_LIST =
    (SID_DESC =
      (SID_NAME = CLRExtProc)
      (ORACLE_HOME = E:\app\user\product\11.2.0\dbhome_1)
      (PROGRAM = extproc)
      (ENVS = "EXTPROC_DLLS=ONLY:E:\app\user\product\11.2.0\dbhome_1\bin\oraclr11.dll")
    )
  )

LISTENER =
  (DESCRIPTION_LIST =
    (DESCRIPTION =
      (ADDRESS = (PROTOCOL = IPC)(KEY = EXTPROC1521))
    )
    (DESCRIPTION =
      (ADDRESS = (PROTOCOL = TCP)(HOST = localhost)(PORT = 1521))
    )
    (DESCRIPTION =
      (ADDRESS = (PROTOCOL = TCP)(HOST = 172.20.14.13)(PORT = 1521))
    )
  )

ADR_BASE_LISTENER = E:\app\user

Third. With Net Manager create Service Naming with IP address computer B (172.20.14.78) or manually add new record in tnsnames.ora

# tnsnames.ora Network Configuration File: E:\app\user\product\11.2.0\dbhome_1\NETWORK\ADMIN\tnsnames.ora
# Generated by Oracle configuration tools.

ALINADB =
  (DESCRIPTION =
    (ADDRESS_LIST =
      (ADDRESS = (PROTOCOL = TCP)(HOST = localhost)(PORT = 1521))
    )
    (CONNECT_DATA =
      (SERVER = DEDICATED)
      (SERVICE_NAME = alinadb)
    )
  )

LISTENER_ALINADB =
  (ADDRESS = (PROTOCOL = TCP)(HOST = localhost)(PORT = 1521))


LOCAL =
  (DESCRIPTION =
    (ADDRESS_LIST =
      (ADDRESS = (PROTOCOL = TCP)(HOST = 172.20.14.13)(PORT = 1521))
    )
    (CONNECT_DATA =
      (SERVER = DEDICATED)
      (SERVICE_NAME = alinadb)
    )
  )

ORACLR_CONNECTION_DATA =
  (DESCRIPTION =
    (ADDRESS_LIST =
      (ADDRESS = (PROTOCOL = IPC)(KEY = EXTPROC1521))
    )
    (CONNECT_DATA =
      (SID = CLRExtProc)
      (PRESENTATION = RO)
    )
  )

ORCL =
  (DESCRIPTION =
    (ADDRESS_LIST =
      (ADDRESS = (PROTOCOL = TCP)(HOST = 172.20.14.78)(PORT = 1521))
    )
    (CONNECT_DATA =
      (SERVER = DEDICATED)
      (SERVICE_NAME = orcl)
    )
  )

Fourth. In computer B (172.20.14.78) install win64_11gR2_client (For example it is for me in Windows 10 Pro 64 bit )

Five. Create with Net Configuration Assistant listener (localhost) or manually add record in listener.ora

# listener.ora Network Configuration File: F:\app\alinasoft\product\11.2.0\client_1\network\admin\listener.ora
# Generated by Oracle configuration tools.

    LISTENER =
      (DESCRIPTION_LIST =
        (DESCRIPTION =
          (ADDRESS = (PROTOCOL = TCP)(HOST = myserver)(PORT = 1521))
          (ADDRESS = (PROTOCOL = IPC)(KEY = EXTPROC1521))
        )
      )

    ADR_BASE_LISTENER = F:\app\alinasoft

Six. With Net Manager create Service Naming with IP address computer A (172.20.14.13) or manually add new record in tnsnames.ora.

SERVER-DB =
  (DESCRIPTION =
    (ADDRESS_LIST =
      (ADDRESS = (PROTOCOL = TCP)(HOST = 172.20.14.13)(PORT = 1521))
    )
    (CONNECT_DATA =
      (SERVER = DEDICATED)
      (SERVICE_NAME = alinadb)
    )
  )

Seven (Computer A - (172.20.14.13)) for database operations and connectivity from remote clients, the following executables must be added to the Windows Firewall exception list: (see image) Oracle_home\bin\oracle.exe - Oracle Database executable Oracle_home\bin\tnslsnr.exe - Oracle Listener

Eight Allow connections for port 1158 (Computer A - (172.20.14.13)) for Oracle Enterprise Manager (https://172.20.14.13:1158/em/console/logon/logon)

Ninth Allow connections for port 1521 ( in and out) (Computer A - (172.20.14.17))

Tenth In computer B 172.20.14.78 sqlplus /NOLOG CONNECT system/oracle@//172.20.14.13:1521/alinadb

If uses Toad, in my case is enter image description here

How do I install chkconfig on Ubuntu?

Install this package in Ubuntu:

apt install sysv-rc-conf

its a substitute for chkconfig cmd.

After install run this cmd:

sysv-rc-conf --list

It'll show all services in all the runlevels. You can also run this:

sysv-rc-conf --level (runlevel number ex:1 2 3 4 5 6 )

Now you can choose which service should be active in boot time.

Center image in table td in CSS

Set a fixed with of your image in your css and add an auto-margin/padding on the image to...

div.image img {
    width: 100px;
    margin: auto;
}

Or set the text-align to center...

td {
    text-align: center;
}

Serialize an object to string

I know this is not really an answer to the question, but based on the number of votes for the question and the accepted answer, I suspect the people are actually using the code to serialize an object to a string.

Using XML serialization adds unnecessary extra text rubbish to the output.

For the following class

public class UserData
{
    public int UserId { get; set; }
}

it generates

<?xml version="1.0" encoding="utf-16"?>
<UserData xmlns:xsd="http://www.w3.org/2001/XMLSchema" 
          xmlns:xsi="http://www.w3.org/2001/XMLSchema-instance">
   <UserId>0</UserId>
</UserData>

Better solution is to use JSON serialization (one of the best is Json.NET). To serialize an object:

var userData = new UserData {UserId = 0};
var userDataString = JsonConvert.SerializeObject(userData);

To deserialize an object:

var userData = JsonConvert.DeserializeObject<UserData>(userDataString);

The serialized JSON string would look like:

{"UserId":0}

How can I generate an MD5 hash?

Another option is to use the Guava Hashing methods:

Hasher hasher = Hashing.md5().newHasher();
hasher.putString("my string");
byte[] md5 = hasher.hash().asBytes();

Handy if you are already using Guava (which if you're not, you probably should be).

How to use JavaScript regex over multiple lines?

[.\n] does not work because . has no special meaning inside of [], it just means a literal .. (.|\n) would be a way to specify "any character, including a newline". If you want to match all newlines, you would need to add \r as well to include Windows and classic Mac OS style line endings: (.|[\r\n]).

That turns out to be somewhat cumbersome, as well as slow, (see KrisWebDev's answer for details), so a better approach would be to match all whitespace characters and all non-whitespace characters, with [\s\S], which will match everything, and is faster and simpler.

In general, you shouldn't try to use a regexp to match the actual HTML tags. See, for instance, these questions for more information on why.

Instead, try actually searching the DOM for the tag you need (using jQuery makes this easier, but you can always do document.getElementsByTagName("pre") with the standard DOM), and then search the text content of those results with a regexp if you need to match against the contents.

How to export data from Excel spreadsheet to Sql Server 2008 table

From your SQL Server Management Studio, you open Object Explorer, go to your database where you want to load the data into, right click, then pick Tasks > Import Data.

This opens the Import Data Wizard, which typically works pretty well for importing from Excel. You can pick an Excel file, pick what worksheet to import data from, you can choose what table to store it into, and what the columns are going to be. Pretty flexible indeed.

You can run this as a one-off, or you can store it as a SQL Server Integration Services (SSIS) package into your file system, or into SQL Server itself, and execute it over and over again (even scheduled to run at a given time, using SQL Agent).

Update: yes, yes, yes, you can do all those things you keep asking - have you even tried at least once to run that wizard??

OK, here it comes - step by step:

Step 1: pick your Excel source

enter image description here

Step 2: pick your SQL Server target database

enter image description here

Step 3: pick your source worksheet (from Excel) and your target table in your SQL Server database; see the "Edit Mappings" button!

enter image description here

Step 4: check (and change, if needed) your mappings of Excel columns to SQL Server columns in the table:

enter image description here

Step 5: if you want to use it later on, save your SSIS package to SQL Server:

enter image description here

Step 6: - success! This is on a 64-bit machine, works like a charm - just do it!!

How do I print to the debug output window in a Win32 app?

You can also use WriteConsole method to print on console.

AllocConsole();
LPSTR lpBuff = "Hello Win32 API";
DWORD dwSize = 0;
WriteConsole(GetStdHandle(STD_OUTPUT_HANDLE), lpBuff, lstrlen(lpBuff), &dwSize, NULL);

Enable vertical scrolling on textarea

Try this: http://jsfiddle.net/8fv6e/8/

It is another version of the answers.

HTML:

<label for="aboutDescription" id="aboutHeading">About</label>
<textarea rows="15" cols="50" id="aboutDescription"
    style="max-height:100px;min-height:100px; resize: none"></textarea>
<a  id="imageURLId" target="_blank">Go to
    HomePage</a>

CSS:

#imageURLId{
font-size: 14px;
font-weight: normal;
resize: none;
overflow-y: scroll;

}

How do I check in JavaScript if a value exists at a certain array index?

You can use Loadsh library to do this more efficiently, like:

if you have an array named "pets", for example:

var pets = ['dog', undefined, 'cat', null];

console.log(_.isEmpty(pets[1])); // true
console.log(_.isEmpty(pets[3])); // true
console.log(_.isEmpty(pets[4])); // false

_.map( pets, (pet, index) => { console.log(index + ': ' + _.isEmpty(pet) ) });

To check all array values for null or undefined values:

_x000D_
_x000D_
var pets = ['dog', undefined, 'cat', null];_x000D_
_x000D_
console.log(_.isEmpty(pets[1])); // true_x000D_
console.log(_.isEmpty(pets[3])); // true_x000D_
console.log(_.isEmpty(pets[4])); // false_x000D_
_x000D_
_.map( pets, (pet, index) => { console.log(index + ': ' + _.isEmpty(pet) ) });
_x000D_
<script src="https://cdnjs.cloudflare.com/ajax/libs/underscore.js/1.8.3/underscore-min.js"></script>
_x000D_
_x000D_
_x000D_

Check more examples in http://underscorejs.org/

URL string format for connecting to Oracle database with JDBC

DriverManager.registerDriver(new oracle.jdbc.driver.OracleDriver());         
connection = DriverManager.getConnection("jdbc:oracle:thin:@machinename:portnum:schemaname","userid","password");

How do I format a number with commas in T-SQL?

`/* Author: Tsiridis Dimitris */
/* Greek amount format. For the other change the change on replace of '.' & ',' */
CREATE FUNCTION dbo.formatAmount  (
@amtIn as varchar(20)
) RETURNS varchar(20)
AS
BEGIN 

return cast(REPLACE(SUBSTRING(CONVERT(varchar(20), CAST(@amtIn AS money), 1),1,
LEN(CONVERT(varchar(20), CAST(@amtIn AS money), 1))-3), ',','.')
 + replace(RIGHT(CONVERT(varchar(20), CAST(@amtIn AS money), 1),3), '.',',') AS VARCHAR(20))

END

SELECT [geniki].[dbo].[formatAmount]('9888777666555.44')`

Ruby: Easiest Way to Filter Hash Keys?

The easiest way is to include the gem 'activesupport' (or gem 'active_support').

params.slice(:choice1, :choice2, :choice3)

Spring - @Transactional - What happens in background?

The simplest answer is:

On whichever method you declare @Transactional the boundary of transaction starts and boundary ends when method completes.

If you are using JPA call then all commits are with in this transaction boundary.

Lets say you are saving entity1, entity2 and entity3. Now while saving entity3 an exception occur, then as enitiy1 and entity2 comes in same transaction so entity1 and entity2 will be rollback with entity3.

Transaction :

  1. entity1.save
  2. entity2.save
  3. entity3.save

Any exception will result in rollback of all JPA transactions with DB.Internally JPA transaction are used by Spring.

How to replace plain URLs with links?

Replacing URLs with links (Answer to the General Problem)

The regular expression in the question misses a lot of edge cases. When detecting URLs, it's always better to use a specialized library that handles international domain names, new TLDs like .museum, parentheses and other punctuation within and at the end of the URL, and many other edge cases. See the Jeff Atwood's blog post The Problem With URLs for an explanation of some of the other issues.

The best summary of URL matching libraries is in Dan Dascalescu's Answer +100
(as of Feb 2014)


"Make a regular expression replace more than one match" (Answer to the specific problem)

Add a "g" to the end of the regular expression to enable global matching:

/ig;

But that only fixes the problem in the question where the regular expression was only replacing the first match. Do not use that code.

Using .NET, how can you find the mime type of a file based on the file signature not the extension

Edit: Just use Mime Detective

I use byte array sequences to determine the correct MIME type of a given file. The advantage of this over just looking at the file extension of the file name is that if a user were to rename a file to bypass certain file type upload restrictions, the file name extension would fail to catch this. On the other hand, getting the file signature via byte array will stop this mischievous behavior from happening.

Here is an example in C#:

public class MimeType
{
    private static readonly byte[] BMP = { 66, 77 };
    private static readonly byte[] DOC = { 208, 207, 17, 224, 161, 177, 26, 225 };
    private static readonly byte[] EXE_DLL = { 77, 90 };
    private static readonly byte[] GIF = { 71, 73, 70, 56 };
    private static readonly byte[] ICO = { 0, 0, 1, 0 };
    private static readonly byte[] JPG = { 255, 216, 255 };
    private static readonly byte[] MP3 = { 255, 251, 48 };
    private static readonly byte[] OGG = { 79, 103, 103, 83, 0, 2, 0, 0, 0, 0, 0, 0, 0, 0 };
    private static readonly byte[] PDF = { 37, 80, 68, 70, 45, 49, 46 };
    private static readonly byte[] PNG = { 137, 80, 78, 71, 13, 10, 26, 10, 0, 0, 0, 13, 73, 72, 68, 82 };
    private static readonly byte[] RAR = { 82, 97, 114, 33, 26, 7, 0 };
    private static readonly byte[] SWF = { 70, 87, 83 };
    private static readonly byte[] TIFF = { 73, 73, 42, 0 };
    private static readonly byte[] TORRENT = { 100, 56, 58, 97, 110, 110, 111, 117, 110, 99, 101 };
    private static readonly byte[] TTF = { 0, 1, 0, 0, 0 };
    private static readonly byte[] WAV_AVI = { 82, 73, 70, 70 };
    private static readonly byte[] WMV_WMA = { 48, 38, 178, 117, 142, 102, 207, 17, 166, 217, 0, 170, 0, 98, 206, 108 };
    private static readonly byte[] ZIP_DOCX = { 80, 75, 3, 4 };

    public static string GetMimeType(byte[] file, string fileName)
    {

        string mime = "application/octet-stream"; //DEFAULT UNKNOWN MIME TYPE

        //Ensure that the filename isn't empty or null
        if (string.IsNullOrWhiteSpace(fileName))
        {
            return mime;
        }

        //Get the file extension
        string extension = Path.GetExtension(fileName) == null
                               ? string.Empty
                               : Path.GetExtension(fileName).ToUpper();

        //Get the MIME Type
        if (file.Take(2).SequenceEqual(BMP))
        {
            mime = "image/bmp";
        }
        else if (file.Take(8).SequenceEqual(DOC))
        {
            mime = "application/msword";
        }
        else if (file.Take(2).SequenceEqual(EXE_DLL))
        {
            mime = "application/x-msdownload"; //both use same mime type
        }
        else if (file.Take(4).SequenceEqual(GIF))
        {
            mime = "image/gif";
        }
        else if (file.Take(4).SequenceEqual(ICO))
        {
            mime = "image/x-icon";
        }
        else if (file.Take(3).SequenceEqual(JPG))
        {
            mime = "image/jpeg";
        }
        else if (file.Take(3).SequenceEqual(MP3))
        {
            mime = "audio/mpeg";
        }
        else if (file.Take(14).SequenceEqual(OGG))
        {
            if (extension == ".OGX")
            {
                mime = "application/ogg";
            }
            else if (extension == ".OGA")
            {
                mime = "audio/ogg";
            }
            else
            {
                mime = "video/ogg";
            }
        }
        else if (file.Take(7).SequenceEqual(PDF))
        {
            mime = "application/pdf";
        }
        else if (file.Take(16).SequenceEqual(PNG))
        {
            mime = "image/png";
        }
        else if (file.Take(7).SequenceEqual(RAR))
        {
            mime = "application/x-rar-compressed";
        }
        else if (file.Take(3).SequenceEqual(SWF))
        {
            mime = "application/x-shockwave-flash";
        }
        else if (file.Take(4).SequenceEqual(TIFF))
        {
            mime = "image/tiff";
        }
        else if (file.Take(11).SequenceEqual(TORRENT))
        {
            mime = "application/x-bittorrent";
        }
        else if (file.Take(5).SequenceEqual(TTF))
        {
            mime = "application/x-font-ttf";
        }
        else if (file.Take(4).SequenceEqual(WAV_AVI))
        {
            mime = extension == ".AVI" ? "video/x-msvideo" : "audio/x-wav";
        }
        else if (file.Take(16).SequenceEqual(WMV_WMA))
        {
            mime = extension == ".WMA" ? "audio/x-ms-wma" : "video/x-ms-wmv";
        }
        else if (file.Take(4).SequenceEqual(ZIP_DOCX))
        {
            mime = extension == ".DOCX" ? "application/vnd.openxmlformats-officedocument.wordprocessingml.document" : "application/x-zip-compressed";
        }

        return mime;
    }


}

Notice I handled DOCX file types differently since DOCX is really just a ZIP file. In this scenario, I simply check the file extension once I verified that it has that sequence. This example is far from complete for some people, but you can easily add your own.

If you want to add more MIME types, you can get the byte array sequences of many different file types from here. Also, here is another good resource concerning file signatures.

What I do a lot of times if all else fails is step through several files of a particular type that I am looking for and look for a pattern in the byte sequence of the files. In the end, this is still basic verification and cannot be used for 100% proof of determining file types.

Pandas: Looking up the list of sheets in an excel file

You can still use the ExcelFile class (and the sheet_names attribute):

xl = pd.ExcelFile('foo.xls')

xl.sheet_names  # see all sheet names

xl.parse(sheet_name)  # read a specific sheet to DataFrame

see docs for parse for more options...

Convert string to date in bash

We can use date -d option

1) Change format to "%Y-%m-%d" format i.e 20121212 to 2012-12-12

date -d '20121212' +'%Y-%m-%d'

2)Get next or last day from a given date=20121212. Like get a date 7 days in past with specific format

date -d '20121212 -7 days' +'%Y-%m-%d'

3) If we are getting date in some variable say dat

dat2=$(date -d "$dat -1 days" +'%Y%m%d')

Uncaught TypeError: undefined is not a function while using jQuery UI

You may see if you are not loading jQuery twice somehow. Especially after your plugin JavaScript file loaded.

I has the same error and found that one of my external PHP files was loading jQuery again.

Assignment inside lambda expression in Python

The pythonic way to track state during iteration is with generators. The itertools way is quite hard to understand IMHO and trying to hack lambdas to do this is plain silly. I'd try:

def keep_last_empty(input):
    last = None
    for item in iter(input):
        if item.name: yield item
        else: last = item
    if last is not None: yield last

output = list(keep_last_empty(input))

Overall, readability trumps compactness every time.

How to pass all arguments passed to my bash script to a function of mine?

Use the $@ variable, which expands to all command-line parameters separated by spaces.

abc "$@"

Finding the median of an unsorted array

Let the problem be: finding the Kth largest element in an unsorted array.

Divide the array into n/5 groups where each group consisting of 5 elements.

Now a1,a2,a3....a(n/5) represent the medians of each group.

x = Median of the elements a1,a2,.....a(n/5).

Now if k<n/2 then we can remove the largets, 2nd largest and 3rd largest element of the groups whose median is greater than the x. We can now call the function again with 7n/10 elements and finding the kth largest value.

else if k>n/2 then we can remove the smallest ,2nd smallest and 3rd smallest element of the group whose median is smaller than the x. We can now call the function of again with 7n/10 elements and finding the (k-3n/10)th largest value.

Time Complexity Analysis: T(n) time complexity to find the kth largest in an array of size n.

T(n) = T(n/5) + T(7n/10) + O(n)

if you solve this you will find out that T(n) is actually O(n)

n/5 + 7n/10 = 9n/10 < n

plotting different colors in matplotlib

for color in ['r', 'b', 'g', 'k', 'm']:
    plot(x, y, color=color)

How to switch from the default ConstraintLayout to RelativeLayout in Android Studio

I think u want to change the default settings of android studio. Whenever a layout or Activity in created u want to create "RelativeLayout" by default. In that case, flow the step below

  1. click any folder u used to create layout or Activity
  2. then "New>> Edit File Templates
  3. then go to "Other" tab
  4. select "LayoutResourceFile.xml" and "LayoutResourceFile_vertical.xml"
  5. change "${ROOT_TAG}" to "RelativeLayout"
  6. click "Ok"

you are done

How to specify more spaces for the delimiter using cut?

If you want to pick columns from a ps output, any reason to not use -o?

e.g.

ps ax -o pid,vsz
ps ax -o pid,cmd

Minimum column width allocated, no padding, only single space field separator.

ps ax --no-headers -o pid:1,vsz:1,cmd

3443 24600 -bash
8419 0 [xfsalloc]
8420 0 [xfs_mru_cache]
8602 489316 /usr/sbin/apache2 -k start
12821 497240 /usr/sbin/apache2 -k start
12824 497132 /usr/sbin/apache2 -k start

Pid and vsz given 10 char width, 1 space field separator.

ps ax --no-headers -o pid:10,vsz:10,cmd

  3443      24600 -bash
  8419          0 [xfsalloc]
  8420          0 [xfs_mru_cache]
  8602     489316 /usr/sbin/apache2 -k start
 12821     497240 /usr/sbin/apache2 -k start
 12824     497132 /usr/sbin/apache2 -k start

Used in a script:-

oldpid=12824
echo "PID: ${oldpid}"
echo "Command: $(ps -ho cmd ${oldpid})"

Sort columns of a dataframe by column name

If you only want one or more columns in the front and don't care about the order of the rest:

require(dplyr)
test %>%
  select(B, everything())

Vertically align text within a div

Add a vertical align to the CSS content #column-content strong too:

#column-content strong {
    ...
    vertical-align: middle;
}

Also see your updated example.

=== UPDATE ===

With a span around the other text and another vertical align:

HTML:

... <span>yet another text content that should be centered vertically</span> ...

CSS:

#column-content span {
    vertical-align: middle;
}

Also see the next example.

How to sort a collection by date in MongoDB?

Sorting by date doesn't require anything special. Just sort by the desired date field of the collection.

Updated for the 1.4.28 node.js native driver, you can sort ascending on datefield using any of the following ways:

collection.find().sort({datefield: 1}).toArray(function(err, docs) {...});
collection.find().sort('datefield', 1).toArray(function(err, docs) {...});
collection.find().sort([['datefield', 1]]).toArray(function(err, docs) {...});
collection.find({}, {sort: {datefield: 1}}).toArray(function(err, docs) {...});
collection.find({}, {sort: [['datefield', 1]]}).toArray(function(err, docs) {...});

'asc' or 'ascending' can also be used in place of the 1.

To sort descending, use 'desc', 'descending', or -1 in place of the 1.

Git Clone from GitHub over https with two-factor authentication

If your repo have 2FA enabled. Highly suggest to use the app provided by github.com Here is the link: https://desktop.github.com/

After you downloaded it and installed it. Follow the withard, the app will ask you to provide the one time password for login. Once you filled in the one time password, you could see your repo/projects now.

Convert pandas data frame to series

It's not smart enough to realize it's still a "vector" in math terms.

Say rather that it's smart enough to recognize a difference in dimensionality. :-)

I think the simplest thing you can do is select that row positionally using iloc, which gives you a Series with the columns as the new index and the values as the values:

>>> df = pd.DataFrame([list(range(5))], columns=["a{}".format(i) for i in range(5)])
>>> df
   a0  a1  a2  a3  a4
0   0   1   2   3   4
>>> df.iloc[0]
a0    0
a1    1
a2    2
a3    3
a4    4
Name: 0, dtype: int64
>>> type(_)
<class 'pandas.core.series.Series'>

WAMP Cannot access on local network 403 Forbidden

To expand on RiggsFolly’s answer—or for anyone who is facing the same issue but is using Apache 2.2 or below—this format should work well:

Order Deny,Allow
Deny from all
Allow from 127.0.0.1 ::1
Allow from localhost
Allow from 192.168
Allow from 10
Satisfy Any

For more details on the format changes for Apache 2.4, the official Upgrading to 2.2 from 2.4 page is pretty clear & concise. Key point being:

The old access control idioms should be replaced by the new authentication mechanisms, although for compatibility with old configurations, the new module mod_access_compat is provided.

Which means, system admins around the world don’t necessarily have to panic about changing Apache 2.2 configs to be 2.4 compliant just yet.

When to use a View instead of a Table?

You should design your table WITHOUT considering the views.
Apart from saving joins and conditions, Views do have a performance advantage: SQL Server may calculate and save its execution plan in the view, and therefore make it faster than "on the fly" SQL statements.
View may also ease your work regarding user access at field level.

How to run shell script on host from docker container?

docker run --detach-keys="ctrl-p" -it -v /:/mnt/rootdir --name testing busybox
# chroot /mnt/rootdir
# 

Run a mySQL query as a cron job?

It depends on what runs cron on your system, but all you have to do to run a php script from cron is to do call the location of the php installation followed by the script location. An example with crontab running every hour:

# crontab -e
00 * * * * /usr/local/bin/php /home/path/script.php

On my system, I don't even have to put the path to the php installation:

00 * * * * php /home/path/script.php

On another note, you should not be using mysql extension because it is deprecated, unless you are using an older installation of php. Read here for a comparison.

Disable browser 'Save Password' functionality

Not really - the only thing you could realistically do is offer advice on the site; maybe, before their first time signing in, you could show them a form with information indicating that it is not recommended that they allow the browser to store the password.

Then the user will immediately follow the advice, write down the password on a post-it note and tape it to their monitor.

Is it possible in Java to access private fields via reflection

Yes it is possible.

You need to use the getDeclaredField method (instead of the getField method), with the name of your private field:

Field privateField = Test.class.getDeclaredField("str");

Additionally, you need to set this Field to be accessible, if you want to access a private field:

privateField.setAccessible(true);

Once that's done, you can use the get method on the Field instance, to access the value of the str field.

Is there a constraint that restricts my generic method to numeric types?

I was wondering the same as samjudson, why only to integers? and if that is the case, you might want to create a helper class or something like that to hold all the types you want.

If all you want are integers, don't use a generic, that is not generic; or better yet, reject any other type by checking its type.

Get operating system info

Based on the answer by Fred-II I wanted to share my take on the getOS function, it avoids globals, merges both lists and detects the architecture (x32/x64)

/**
 * @param $user_agent null
 * @return string
 */
function getOS($user_agent = null)
{
    if(!isset($user_agent) && isset($_SERVER['HTTP_USER_AGENT'])) {
        $user_agent = $_SERVER['HTTP_USER_AGENT'];
    }

    // https://stackoverflow.com/questions/18070154/get-operating-system-info-with-php
    $os_array = [
        'windows nt 10'                              =>  'Windows 10',
        'windows nt 6.3'                             =>  'Windows 8.1',
        'windows nt 6.2'                             =>  'Windows 8',
        'windows nt 6.1|windows nt 7.0'              =>  'Windows 7',
        'windows nt 6.0'                             =>  'Windows Vista',
        'windows nt 5.2'                             =>  'Windows Server 2003/XP x64',
        'windows nt 5.1'                             =>  'Windows XP',
        'windows xp'                                 =>  'Windows XP',
        'windows nt 5.0|windows nt5.1|windows 2000'  =>  'Windows 2000',
        'windows me'                                 =>  'Windows ME',
        'windows nt 4.0|winnt4.0'                    =>  'Windows NT',
        'windows ce'                                 =>  'Windows CE',
        'windows 98|win98'                           =>  'Windows 98',
        'windows 95|win95'                           =>  'Windows 95',
        'win16'                                      =>  'Windows 3.11',
        'mac os x 10.1[^0-9]'                        =>  'Mac OS X Puma',
        'macintosh|mac os x'                         =>  'Mac OS X',
        'mac_powerpc'                                =>  'Mac OS 9',
        'linux'                                      =>  'Linux',
        'ubuntu'                                     =>  'Linux - Ubuntu',
        'iphone'                                     =>  'iPhone',
        'ipod'                                       =>  'iPod',
        'ipad'                                       =>  'iPad',
        'android'                                    =>  'Android',
        'blackberry'                                 =>  'BlackBerry',
        'webos'                                      =>  'Mobile',

        '(media center pc).([0-9]{1,2}\.[0-9]{1,2})'=>'Windows Media Center',
        '(win)([0-9]{1,2}\.[0-9x]{1,2})'=>'Windows',
        '(win)([0-9]{2})'=>'Windows',
        '(windows)([0-9x]{2})'=>'Windows',

        // Doesn't seem like these are necessary...not totally sure though..
        //'(winnt)([0-9]{1,2}\.[0-9]{1,2}){0,1}'=>'Windows NT',
        //'(windows nt)(([0-9]{1,2}\.[0-9]{1,2}){0,1})'=>'Windows NT', // fix by bg

        'Win 9x 4.90'=>'Windows ME',
        '(windows)([0-9]{1,2}\.[0-9]{1,2})'=>'Windows',
        'win32'=>'Windows',
        '(java)([0-9]{1,2}\.[0-9]{1,2}\.[0-9]{1,2})'=>'Java',
        '(Solaris)([0-9]{1,2}\.[0-9x]{1,2}){0,1}'=>'Solaris',
        'dos x86'=>'DOS',
        'Mac OS X'=>'Mac OS X',
        'Mac_PowerPC'=>'Macintosh PowerPC',
        '(mac|Macintosh)'=>'Mac OS',
        '(sunos)([0-9]{1,2}\.[0-9]{1,2}){0,1}'=>'SunOS',
        '(beos)([0-9]{1,2}\.[0-9]{1,2}){0,1}'=>'BeOS',
        '(risc os)([0-9]{1,2}\.[0-9]{1,2})'=>'RISC OS',
        'unix'=>'Unix',
        'os/2'=>'OS/2',
        'freebsd'=>'FreeBSD',
        'openbsd'=>'OpenBSD',
        'netbsd'=>'NetBSD',
        'irix'=>'IRIX',
        'plan9'=>'Plan9',
        'osf'=>'OSF',
        'aix'=>'AIX',
        'GNU Hurd'=>'GNU Hurd',
        '(fedora)'=>'Linux - Fedora',
        '(kubuntu)'=>'Linux - Kubuntu',
        '(ubuntu)'=>'Linux - Ubuntu',
        '(debian)'=>'Linux - Debian',
        '(CentOS)'=>'Linux - CentOS',
        '(Mandriva).([0-9]{1,3}(\.[0-9]{1,3})?(\.[0-9]{1,3})?)'=>'Linux - Mandriva',
        '(SUSE).([0-9]{1,3}(\.[0-9]{1,3})?(\.[0-9]{1,3})?)'=>'Linux - SUSE',
        '(Dropline)'=>'Linux - Slackware (Dropline GNOME)',
        '(ASPLinux)'=>'Linux - ASPLinux',
        '(Red Hat)'=>'Linux - Red Hat',
        // Loads of Linux machines will be detected as unix.
        // Actually, all of the linux machines I've checked have the 'X11' in the User Agent.
        //'X11'=>'Unix',
        '(linux)'=>'Linux',
        '(amigaos)([0-9]{1,2}\.[0-9]{1,2})'=>'AmigaOS',
        'amiga-aweb'=>'AmigaOS',
        'amiga'=>'Amiga',
        'AvantGo'=>'PalmOS',
        //'(Linux)([0-9]{1,2}\.[0-9]{1,2}\.[0-9]{1,3}(rel\.[0-9]{1,2}){0,1}-([0-9]{1,2}) i([0-9]{1})86){1}'=>'Linux',
        //'(Linux)([0-9]{1,2}\.[0-9]{1,2}\.[0-9]{1,3}(rel\.[0-9]{1,2}){0,1} i([0-9]{1}86)){1}'=>'Linux',
        //'(Linux)([0-9]{1,2}\.[0-9]{1,2}\.[0-9]{1,3}(rel\.[0-9]{1,2}){0,1})'=>'Linux',
        '[0-9]{1,2}\.[0-9]{1,2}\.[0-9]{1,3}'=>'Linux',
        '(webtv)/([0-9]{1,2}\.[0-9]{1,2})'=>'WebTV',
        'Dreamcast'=>'Dreamcast OS',
        'GetRight'=>'Windows',
        'go!zilla'=>'Windows',
        'gozilla'=>'Windows',
        'gulliver'=>'Windows',
        'ia archiver'=>'Windows',
        'NetPositive'=>'Windows',
        'mass downloader'=>'Windows',
        'microsoft'=>'Windows',
        'offline explorer'=>'Windows',
        'teleport'=>'Windows',
        'web downloader'=>'Windows',
        'webcapture'=>'Windows',
        'webcollage'=>'Windows',
        'webcopier'=>'Windows',
        'webstripper'=>'Windows',
        'webzip'=>'Windows',
        'wget'=>'Windows',
        'Java'=>'Unknown',
        'flashget'=>'Windows',

        // delete next line if the script show not the right OS
        //'(PHP)/([0-9]{1,2}.[0-9]{1,2})'=>'PHP',
        'MS FrontPage'=>'Windows',
        '(msproxy)/([0-9]{1,2}.[0-9]{1,2})'=>'Windows',
        '(msie)([0-9]{1,2}.[0-9]{1,2})'=>'Windows',
        'libwww-perl'=>'Unix',
        'UP.Browser'=>'Windows CE',
        'NetAnts'=>'Windows',
    ];

    // https://github.com/ahmad-sa3d/php-useragent/blob/master/core/user_agent.php
    $arch_regex = '/\b(x86_64|x86-64|Win64|WOW64|x64|ia64|amd64|ppc64|sparc64|IRIX64)\b/ix';
    $arch = preg_match($arch_regex, $user_agent) ? '64' : '32';

    foreach ($os_array as $regex => $value) {
        if (preg_match('{\b('.$regex.')\b}i', $user_agent)) {
            return $value.' x'.$arch;
        }
    }

    return 'Unknown';
}

Most concise way to convert a Set<T> to a List<T>

List<String> l = new ArrayList<String>(listOfTopicAuthors);

Query to check index on a table

check this as well This gives an overview of associated constraints across a database. Please also include facilitating where condition with table name of interest so gives information faster.

   select 
a.TABLE_CATALOG as DB_name,a.TABLE_SCHEMA as tbl_schema, a.TABLE_NAME as tbl_name,a. CONSTRAINT_NAME as constraint_name,b.CONSTRAINT_TYPE
 from INFORMATION_SCHEMA.CONSTRAINT_COLUMN_USAGE a
join INFORMATION_SCHEMA.TABLE_CONSTRAINTS b on
 a.CONSTRAINT_NAME=b.CONSTRAINT_NAME

Redefining the Index in a Pandas DataFrame object

If you don't want 'a' in the index

In :

col = ['a','b','c']

data = DataFrame([[1,2,3],[10,11,12],[20,21,22]],columns=col)

data

Out:

    a   b   c
0   1   2   3
1  10  11  12
2  20  21  22

In :

data2 = data.set_index('a')

Out:

     b   c
a
1    2   3
10  11  12
20  21  22

In :

data2.index.name = None

Out:

     b   c
 1   2   3
10  11  12
20  21  22

How to change Toolbar home icon color

Well there is a more easy way to do this

drawerToggle = new ActionBarDrawerToggle(this, drawer, toolbar, R.string.open_drawer, R.string.close_drawer);
arrow = drawerToggle.getDrawerArrowDrawable();

And then

arrow.setColor(getResources().getColor(R.color.blue);

The type List is not generic; it cannot be parameterized with arguments [HTTPClient]

Your import has a subtle error:

import java.awt.List;

It should be:

import java.util.List;

The problem is that both awt and Java's util package provide a class called List. The former is a display element, the latter is a generic type used with collections. Furthermore, java.util.ArrayList extends java.util.List, not java.awt.List so if it wasn't for the generics, it would have still been a problem.

Edit: (to address further questions given by OP) As an answer to your comment, it seems that there is anther subtle import issue.

import org.omg.DynamicAny.NameValuePair;

should be

import org.apache.http.NameValuePair

nameValuePairs now uses the correct generic type parameter, the generic argument for new UrlEncodedFormEntity, which is List<? extends NameValuePair>, becomes valid, since your NameValuePair is now the same as their NameValuePair. Before, org.omg.DynamicAny.NameValuePair did not extend org.apache.http.NameValuePair and the shortened type name NameValuePair evaluated to org.omg... in your file, but org.apache... in their code.

How to check whether a string is Base64 encoded or not

There is no way to distinct string and base64 encoded, except the string in your system has some specific limitation or identification.

How to output loop.counter in python jinja template?

The counter variable inside the loop is called loop.index in jinja2.

>>> from jinja2 import Template

>>> s = "{% for element in elements %}{{loop.index}} {% endfor %}"
>>> Template(s).render(elements=["a", "b", "c", "d"])
1 2 3 4

See http://jinja.pocoo.org/docs/templates/ for more.

An unhandled exception was generated during the execution of the current web request

In my case, I created a new project and when I ran it the first time, it gave me the following error:

An unhandled exception was generated during the execution of the current web request. Information regarding the origin and location of the exception can be identified using the exception stack trace below.

So my solution was to go to the Package Manager Console inside the Visual Studio and run:Update-Package

Problem solved!!

How to get PID of process I've just started within java program?

If portability is not a concern, and you just want to get the pid on Windows without a lot of hassle while using code that is tested and known to work on all modern versions of Windows, you can use kohsuke's winp library. It is also available on Maven Central for easy consumption.

Process process = //...;
WinProcess wp = new WinProcess(process);
int pid = wp.getPid();

Calling one Bash script from another Script passing it arguments with quotes and spaces

You need to use : "$@" (WITH the quotes) or "${@}" (same, but also telling the shell where the variable name starts and ends).

(and do NOT use : $@, or "$*", or $*).

ex:

#testscript1:
echo "TestScript1 Arguments:"
for an_arg in "$@" ; do
   echo "${an_arg}"
done
echo "nb of args: $#"
./testscript2 "$@"   #invokes testscript2 with the same arguments we received

I'm not sure I understood your other requirement ( you want to invoke './testscript2' in single quotes?) so here are 2 wild guesses (changing the last line above) :

'./testscript2' "$@"  #only makes sense if "/path/to/testscript2" containes spaces?

./testscript2 '"some thing" "another"' "$var" "$var2"  #3 args to testscript2

Please give me the exact thing you are trying to do

edit: after his comment saying he attempts tesscript1 "$1" "$2" "$3" "$4" "$5" "$6" to run : salt 'remote host' cmd.run './testscript2 $1 $2 $3 $4 $5 $6'

You have many levels of intermediate: testscript1 on host 1, needs to run "salt", and give it a string launching "testscrit2" with arguments in quotes...

You could maybe "simplify" by having:

#testscript1

#we receive args, we generate a custom script simulating 'testscript2 "$@"'
theargs="'$1'"
shift
for i in "$@" ; do
   theargs="${theargs} '$i'"
done

salt 'remote host' cmd.run "./testscript2 ${theargs}"

if THAt doesn't work, then instead of running "testscript2 ${theargs}", replace THE LAST LINE above by

echo "./testscript2 ${theargs}" >/tmp/runtestscript2.$$  #generate custom script locally ($$ is current pid in bash/sh/...)
scp /tmp/runtestscript2.$$ user@remotehost:/tmp/runtestscript2.$$ #copy it to remotehost
salt 'remotehost' cmd.run "./runtestscript2.$$" #the args are inside the custom script!
ssh user@remotehost "rm /tmp/runtestscript2.$$" #delete the remote one
rm /tmp/runtestscript2.$$ #and the local one

How to check for an empty object in an AngularJS view

I had to validate an empty object check as below

ex:

<div  data-ng-include="'/xx/xx/xx/regtabs.html'" data-ng-if =
    "$parent.$eval((errors | json) != '{}')" >
</div>

The error is my scope object, it is being defined in my controller as $scope.error = {};

Copy data into another table

If both tables are truly the same schema:

INSERT INTO newTable
SELECT * FROM oldTable

Otherwise, you'll have to specify the column names (the column list for newTable is optional if you are specifying a value for all columns and selecting columns in the same order as newTable's schema):

INSERT INTO newTable (col1, col2, col3)
SELECT column1, column2, column3
FROM oldTable

Getting Error:JRE_HOME variable is not defined correctly when trying to run startup.bat of Apache-Tomcat

Your JRE_HOME does not need to point to the "bin" directory. Just set it to C:\Program Files\Java\jre1.8.0_25

Show spinner GIF during an $http request in AngularJS?

This works well for me:

HTML:

  <div id="loader" class="ng-hide" ng-show="req.$$state.pending">
    <img class="ajax-loader" 
         width="200" 
         height="200" 
         src="/images/spinner.gif" />
  </div>

Angular:

  $scope.req = $http.get("/admin/view/"+id).success(function(data) {          
      $scope.data = data;
  });

While the promise returned from $http is pending, ng-show will evaluate it to be "truthy". This is automatically updated once the promise is resolved... which is exactly what we want.

How to migrate GIT repository from one server to a new one

Copy it over. It's really that simple. :)

On the client side, just edit .git/config in the client's local repo to point your remotes to the new URL as necessary.

Change MySQL default character set to UTF-8 in my.cnf?

MySQL v5.5.3 and greater:

Just add three lines only in the [mysqld] section:

[mysqld]
character-set-server = utf8
collation-server = utf8_unicode_ci
skip-character-set-client-handshake

Note: Including skip-character-set-client-handshake here obviates the need to include both init-connect in [mysqld] and default-character-set in the [client] and [mysql] sections.

Why is an OPTIONS request sent and can I disable it?

What worked for me was to import "github.com/gorilla/handlers" and then use it this way:

router := mux.NewRouter()
router.HandleFunc("/config", getConfig).Methods("GET")
router.HandleFunc("/config/emcServer", createEmcServers).Methods("POST")

headersOk := handlers.AllowedHeaders([]string{"X-Requested-With", "Content-Type"})
originsOk := handlers.AllowedOrigins([]string{"*"})
methodsOk := handlers.AllowedMethods([]string{"GET", "HEAD", "POST", "PUT", "OPTIONS"})

log.Fatal(http.ListenAndServe(":" + webServicePort, handlers.CORS(originsOk, headersOk, methodsOk)(router)))

As soon as I executed an Ajax POST request and attaching JSON data to it, Chrome would always add the Content-Type header which was not in my previous AllowedHeaders config.

HTML CSS How to stop a table cell from expanding

It appears that your HTML syntax is incorrect for the table cell. Before you try the other idea below, confirm if this works or not... You can also try adding this to your table itself: table-layout:fixed.. .

<td style="overflow: hidden; width: 280px; text-align: left; valign: top; whitespace: nowrap;">
   [content]
</td>

New HTML

<td>
   <div class="MyClass"">
       [content]
   </div>
</td>

CSS Class:

.MyClass{
   height: 280px; 
   width: 456px; 
   overflow: hidden;
   white-space: nowrap;
}

Configuring IntelliJ IDEA for unit testing with JUnit

Press Ctrl+Shift+T in the code editor. It will show you popup with suggestion to create a test.

Mac OS: ? Cmd+Shift+T

How to get the last N records in mongodb?

In order to get last N records you can execute below query:

db.yourcollectionname.find({$query: {}, $orderby: {$natural : -1}}).limit(yournumber)

if you want only one last record:

db.yourcollectionname.findOne({$query: {}, $orderby: {$natural : -1}})

Note: In place of $natural you can use one of the columns from your collection.

Is it possible to make input fields read-only through CSS?

Why not hide the input element and replace it with a label element with the same content?

I puzzled over how the React TODOMVC app accomplished this same thing and this is the strategy they came up with.

To see it in action, check out the app below, and watch the CSS properties of the TODO items when you double click them and then click away.

http://todomvc.com/examples/react-backbone/#/

When you render the page you can have either an editable input, or a non-editable label with display:none; depending on your media query.

How can I require at least one checkbox be checked before a form can be submitted?

Make all the checkboxes required and add a change listener. If any one checkbox is ticked, remove required attribute from all the checkboxes. Below is a sample code.

<div class="form-group browsers">
    <label class="control-label col-md-4" for="optiontext">Select an option</label>
    <div class="col-md-6">
        <input type="checkbox" name="browser" value="Chrome" required/> Google Chrome<br>
        <input type="checkbox" name="browser" value="IE" required/> Internet Explorer<br>
        <input type="checkbox" name="browser" value="Mozilla" required/> Mozilla Firefox<br>
        <input type="checkbox" name="browser" value="Edge" required/> Microsoft Edge
    </div>
</div>

Change listener :

$(function(){
    var requiredCheckboxes = $('.browsers :checkbox[required]');
    requiredCheckboxes.change(function(){
        if(requiredCheckboxes.is(':checked')) {
            requiredCheckboxes.removeAttr('required');
        } else {
            requiredCheckboxes.attr('required', 'required');
        }
    });
});

How to add Tomcat Server in eclipse

Right Click on the server tab, go for NEW-> Server. then choose recent version of tomcat server. Click on next, and then give path for your tomcat server.(You can download tomcat server from this link https://tomcat.apache.org/download-80.cgi#8.5.32). Click on finish.

You can start your server now..!!

Update Fragment from ViewPager

Update Fragment from ViewPager

You need to implement getItemPosition(Object obj) method.

This method is called when you call

notifyDataSetChanged()

on your ViewPagerAdaper. Implicitly this method returns POSITION_UNCHANGED value that means something like this: "Fragment is where it should be so don't change anything."

So if you need to update Fragment you can do it with:

  • Always return POSITION_NONE from getItemPosition() method. It which means: "Fragment must be always recreated"
  • You can create some update() method that will update your Fragment(fragment will handle updates itself)

Example of second approach:

public interface Updateable {
   public void update();
}


public class MyFragment extends Fragment implements Updateable {

   ...

   public void update() {
     // do your stuff
   }
}

And in FragmentPagerAdapter you'll do something like this:

@Override
public int getItemPosition(Object object) {
   MyFragment f = (MyFragment ) object;
   if (f != null) {
      f.update();
   }
  return super.getItemPosition(object);
}

And if you'll choose first approach it can looks like:

@Override
public int getItemPosition(Object object) {
   return POSITION_NONE;
}

Note: It's worth to think a about which approach you'll pick up.

memory error in python

If you get an unexpected MemoryError and you think you should have plenty of RAM available, it might be because you are using a 32-bit python installation.

The easy solution, if you have a 64-bit operating system, is to switch to a 64-bit installation of python.

The issue is that 32-bit python only has access to ~4GB of RAM. This can shrink even further if your operating system is 32-bit, because of the operating system overhead.

You can learn more about why 32-bit operating systems are limited to ~4GB of RAM here: https://superuser.com/questions/372881/is-there-a-technical-reason-why-32-bit-windows-is-limited-to-4gb-of-ram

Fatal error: Call to undefined function pg_connect()

I had the same symptom in win7. I got this script:

<?php
    phpinfo();
    pg_connect("blah");

When I executed the phpinfo.php script via apache (http://localhost/phpinfo.php) then I got the error message: Call to undefined function pg_connect() in...

When I executed the same script from command line (php phpinfo.php) then I got the expected message: PHP Warning: pg_connect(): Unable to connect to PostgreSQL server: missing "=" after "blah"

In both cases the expected php.ini was used:

Loaded Configuration File   C:\Program Files (x86)\php\php.ini 

but the pgsql section was completely missing from the phpinfo in case of the apache-based execution and it was present in the command-line-based execution.

The solution was that I added the following line to the apache httpd.conf:

LoadFile "C:/Program Files (x86)/php/libpq.dll"

It seems that for some reason this file is not loaded automatically when apache runs the php script but it is loaded if I run the php script from the command line.

I hope it helps.

Git Commit Messages: 50/72 Formatting

Is the maximum recommended title length really 50?

I have believed this for years, but as I just noticed the documentation of "git commit" actually states

$ git help commit | grep -C 1 50
      Though not required, it’s a good idea to begin the commit message with
      a single short (less than 50 character) line summarizing the change,
      followed by a blank line and then a more thorough description. The text

$  git version
git version 2.11.0

One could argue that "less then 50" can only mean "no longer than 49".

How to put a symbol above another in LaTeX?

If you're using # as an operator, consider defining a new operator for it:

\newcommand{\pound}{\operatornamewithlimits{\#}}

You can then write things like \pound_{n = 1}^N and get:

alt text

Generator expressions vs. list comprehensions

Iterating over the generator expression or the list comprehension will do the same thing. However, the list comprehension will create the entire list in memory first while the generator expression will create the items on the fly, so you are able to use it for very large (and also infinite!) sequences.

How to increase Java heap space for a tomcat app

There is a mechanism to do it without modifying any files that are in the distribution. You can create a separate file %CATALINA_HOME%\bin\setenv.bat or $CATALINA_HOME/bin/setenv.sh and put your environment variables there. Further, the memory settings apply to the JVM, not Tomcat, so I'd set the JAVA_OPTS variable instead:

set JAVA_OPTS=-Xmx512m

Why should you use strncpy instead of strcpy?

While I know the intent behind strncpy, it is not really a good function. Avoid both. Raymond Chen explains.

Personally, my conclusion is simply to avoid strncpy and all its friends if you are dealing with null-terminated strings. Despite the "str" in the name, these functions do not produce null-terminated strings. They convert a null-terminated string into a raw character buffer. Using them where a null-terminated string is expected as the second buffer is plain wrong. Not only do you fail to get proper null termination if the source is too long, but if the source is short you get unnecessary null padding.

See also Why is strncpy insecure?

Conditional WHERE clause with CASE statement in Oracle

You can write the where clause as:

where (case when (:stateCode = '') then (1)
            when (:stateCode != '') and (vw.state_cd in (:stateCode)) then 1
            else 0)
       end) = 1;

Alternatively, remove the case entirely:

where (:stateCode = '') or
      ((:stateCode != '') and vw.state_cd in (:stateCode));

Or, even better:

where (:stateCode = '') or vw.state_cd in (:stateCode)

How do I set the time zone of MySQL?

On Windows (IIS) in order to be able to SET GLOBAL time_zone = 'Europe/Helsinki' (or whatever) the MySQL time_zone description tables need to be populated first.

I downloaded these from this link https://dev.mysql.com/downloads/timezones.html

After running the downloaded SQL query I was able to set the GLOBAL time_zone and resolve the issue I had where SELECT NOW(); was returning GMT rather than BST.

Use of exit() function

The exit() function is a type of function with a return type without an argument. It's defined by the stdlib header file.

You need to use ( exit(0) or exit(EXIT_SUCCESS)) or (exit(non-zero) or exit(EXIT_FAILURE) ).

Auto expand a textarea using jQuery

Solution with pure JS

function autoSize() {
  if (element) {
    element.setAttribute('rows', 2) // minimum rows
    const rowsRequired = parseInt(
      (element.scrollHeight - TEXTAREA_CONFIG.PADDING) / TEXTAREA_CONFIG.LINE_HEIGHT
    )
    if (rowsRequired !== parseInt(element.getAttribute('rows'))) {
      element.setAttribute('rows', rowsRequired)
    }
  }
}

https://jsfiddle.net/Samb102/cjqa2kf4/54/

How to get input text length and validate user in javascript

JavaScript validation is not secure as anybody can change what your script does in the browser. Using it for enhancing the visual experience is ok though.

var textBox = document.getElementById("myTextBox");
var textLength = textBox.value.length;
if(textLength > 5)
{
    //red
    textBox.style.backgroundColor = "#FF0000";
}
else
{
    //green
    textBox.style.backgroundColor = "#00FF00";
}

Correct set of dependencies for using Jackson mapper

I spent few hours on this.

Even if I had the right dependency the problem was fixed only after I deleted the com.fasterxml.jackson folder in the .m2 repository under C:\Users\username.m2 and updated the project

How to parse an RSS feed using JavaScript?

You can use jquery-rss or Vanilla RSS, which comes with nice templating and is super easy to use:

// Example for jquery.rss
$("#your-div").rss("https://stackoverflow.com/feeds/question/10943544", {
    limit: 3,
    layoutTemplate: '<ul class="inline">{entries}</ul>',
    entryTemplate: '<li><a href="{url}">[{author}@{date}] {title}</a><br/>{shortBodyPlain}</li>'
})

// Example for Vanilla RSS
const RSS = require('vanilla-rss');
const rss = new RSS(
    document.querySelector("#your-div"),
    "https://stackoverflow.com/feeds/question/10943544",
    { 
      // options go here
    }
);
rss.render().then(() => {
  console.log('Everything is loaded and rendered');
});

See http://jsfiddle.net/sdepold/ozq2dn9e/1/ for a working example.

Determine path of the executing script

The answer of rakensi from Getting path of an R script is the most correct and really brilliant IMHO. Yet, it's still a hack incorporating a dummy function. I'm quoting it here, in order to have it easier found by others.

sourceDir <- getSrcDirectory(function(dummy) {dummy})

This gives the directory of the file where the statement was placed (where the dummy function is defined). It can then be used to set the working direcory and use relative paths e.g.

setwd(sourceDir)
source("other.R")

or to create absolute paths

 source(paste(sourceDir, "/other.R", sep=""))

Git fails when pushing commit to github

If this command not help

git config http.postBuffer 524288000

Try to change ssh method to https

git remote -v
git remote rm origin 
git remote add origin https://github.com/username/project.git

'printf' vs. 'cout' in C++

I'm not a programmer, but I have been a human factors engineer. I feel a programming language should be easy to learn, understand and use, and this requires that it have a simple and consistent linguistic structure. Although all the languages is symbolic and thus, at its core, arbitrary, there are conventions and following them makes the language easier to learn and use.

There are a vast number of functions in C++ and other languages written as function(parameter), a syntax that was originally used for functional relationships in mathematics in the pre-computer era. printf() follows this syntax and if the writers of C++ wanted to create any logically different method for reading and writing files they could have simply created a different function using a similar syntax.

In Python we of course can print using the also fairly standard object.method syntax, i.e. variablename.print, since variables are objects, but in C++ they are not.

I'm not fond of the cout syntax because the << operator does not follow any rules. It is a method or function, i.e. it takes a parameter and does something to it. However it is written as though it were a mathematical comparison operator. This is a poor approach from a human factors standpoint.

Undefined behavior and sequence points

In C99(ISO/IEC 9899:TC3) which seems absent from this discussion thus far the following steteents are made regarding order of evaluaiton.

[...]the order of evaluation of subexpressions and the order in which side effects take place are both unspecified. (Section 6.5 pp 67)

The order of evaluation of the operands is unspecified. If an attempt is made to modify the result of an assignment operator or to access it after the next sequence point, the behavior[sic] is undefined.(Section 6.5.16 pp 91)

How to correct "TypeError: 'NoneType' object is not subscriptable" in recursive function?

One of the values you pass on to Ancestors becomes None at some point, it says, so check if otu, tree, tree[otu] or tree[otu][0] are None in the beginning of the function instead of only checking tree[otu][0][0] == None. But perhaps you should reconsider your path of action and the datatype in question to see if you could improve the structure somewhat.

java.sql.SQLException Parameter index out of range (1 > number of parameters, which is 0)

This is an issue with the jdbc Driver version. I had this issue when I was using mysql-connector-java-commercial-5.0.3-bin.jar but when I changed to a later driver version mysql-connector-java-5.1.22.jar, the issue was fixed.

Should MySQL have its timezone set to UTC?

PHP and MySQL have their own default timezone configurations. You should synchronize time between your data base and web application, otherwise you could run some issues.

Read this tutorial: How To Synchronize Your PHP and MySQL Timezones

Substitute multiple whitespace with single whitespace in Python

A simple possibility (if you'd rather avoid REs) is

' '.join(mystring.split())

The split and join perform the task you're explicitly asking about -- plus, they also do the extra one that you don't talk about but is seen in your example, removing trailing spaces;-).

SQL Server after update trigger

You should be able to access the INSERTED table and retrieve ID or table's primary key. Something similar to this example ...

CREATE TRIGGER [dbo].[after_update] ON [dbo].[MYTABLE]
AFTER UPDATE AS 
BEGIN
    DECLARE @id AS INT
    SELECT @id = [IdColumnName]
    FROM INSERTED

    UPDATE MYTABLE 
    SET mytable.CHANGED_ON = GETDATE(),
    CHANGED_BY=USER_NAME(USER_ID())
    WHERE [IdColumnName] = @id

Here's a link on MSDN on the INSERTED and DELETED tables available when using triggers: http://msdn.microsoft.com/en-au/library/ms191300.aspx

What is the difference between DBMS and RDBMS?

DBMS: is a software system that allows Defining, Creation, Querying, Update, and Administration of data stored in data files.

Features:

  • Normal book keeping system, Flat files, MS Excel, FoxPRO, XML, etc.
  • Less or No provision for: Constraints, Security, ACID rules, users, etc.

RDBMS: is a DBMS that is based on Relational model that stores data in tabular form.

  • SQL Server, Sybase, Oracle, MySQL, IBM DB2, MS Access, etc.

Features:

  • Database, with Tables having relations maintained by FK
  • DDL, DML
  • Data Integrity & ACID rules
  • Multiple User Access
  • Backup & Restore
  • Database Administration

Why are there two ways to unstage a file in Git?

I'm surprised noone mentioned the git reflog (http://git-scm.com/docs/git-reflog):

# git reflog
<find the place before your staged anything>
# git reset HEAD@{1}

The reflog is a git history that not only tracks the changes to the repo, but also tracks the user actions (Eg. pull, checkout to different branch, etc) and allows to undo those actions. So instead of unstaging the file that was mistakingly staged, where you can revert to the point where you didn't stage the files.

This is similar to git reset HEAD <file> but in certain cases may be more granular.

Sorry - not really answering your question, but just pointing yet another way to unstage files that I use quite often (I for one like answers by Ryan Stewart and waldyrious very much.) ;) I hope it helps.

Numpy `ValueError: operands could not be broadcast together with shape ...`

If X and beta do not have the same shape as the second term in the rhs of your last line (i.e. nsample), then you will get this type of error. To add an array to a tuple of arrays, they all must be the same shape.

I would recommend looking at the numpy broadcasting rules.

hash keys / values as array

var myHash = {"apples": 3, "oranges": 4, "bananas": 42}
vals=(function(e){a=[];for (var i in e) a.push(e[i]); return a;})(myHash).join(',')
keys=(function(e){a=[];for (var i in e) a.push(  i ); return a;})(myHash).join(',')
console.log(vals,keys)

basically

array=(function(e){a=[];for (var i in e) a.push(e[i]); return a;})(HASHHERE)

How to run crontab job every week on Sunday

10 * * * Sun

Position 1 for minutes, allowed values are 1-60
position 2 for hours, allowed values are 1-24
position 3 for day of month ,allowed values are 1-31
position 4 for month ,allowed values are 1-12 
position 5 for day of week ,allowed values are 1-7 or and the day starts at Monday. 

Android Studio - Gradle sync project failed

After applying this fix that was found here... https://code.google.com/p/android/issues/detail?id=208295

in file $SDK/ndk_bundle/source.properties replace "12.0.2753695 beta 1" to "12.0.2753695-beta1"

My project was built successfully and ran on device and emulators although 5 warnings still remains.

What is "android:allowBackup"?

This is not explicitly mentioned, but based on the following docs, I think it is implied that an app needs to declare and implement a BackupAgent in order for data backup to work, even in the case when allowBackup is set to true (which is the default value).

http://developer.android.com/reference/android/R.attr.html#allowBackup http://developer.android.com/reference/android/app/backup/BackupManager.html http://developer.android.com/guide/topics/data/backup.html

Palindrome check in Javascript

Maybe I will suggest alternative solution:

function checkPalindrom (str) {
  return str == str.split('').reverse().join('');
}

UPD. Keep in mind however that this is pretty much "cheating" approach, a demonstration of smart usage of language features, but not the most practical algorithm (time O(n), space O(n)). For real life application or coding interview you should definitely use loop solution. The one posted by Jason Sebring in this thread is both simple and efficient (time O(n), space O(1)).

Rails 4 LIKE query - ActiveRecord adds quotes

.find(:all, where: "value LIKE product_%", params: { limit: 20, page: 1 })

MySQL LIMIT on DELETE statement

DELETE t.* FROM test t WHERE t.name = 'foo' LIMIT 1

@Andre If I understood what you are asking, I think the only thing missing is the t.* before FROM.

How to make a input field readonly with JavaScript?

document.getElementById("").readOnly = true

How to run JUnit tests with Gradle?

testCompile is deprecated. Gradle 7 compatible:

dependencies {
...
   testImplementation 'junit:junit:4.13'
}

and if you use the default folder structure (src/test/java/...) the test section is simply:

test {
    useJUnit()
}

Finally:

gradlew clean test

Alos see: https://docs.gradle.org/current/userguide/java_testing.html

How to define a variable in a Dockerfile?

You can use ARG variable defaultValue and during the run command you can even update this value using --build-arg variable=value. To use these variables in the docker file you can refer them as $variable in run command.

Note: These variables would be available for Linux commands like RUN echo $variable and they wouldn't persist in the image.

How to change the opacity (alpha, transparency) of an element in a canvas element after it has been drawn?

You can't. It's immediate mode graphics. But you can sort of simulate it by drawing a rectangle over it in the background color with an opacity.

If the image is over something other than a constant color, then it gets quite a bit trickier. You should be able to use the pixel manipulation methods in this case. Just save the area before drawing the image, and then blend that back on top with an opacity afterwards.

Can a Byte[] Array be written to a file in C#?

Yep, why not?

fs.Write(myByteArray, 0, myByteArray.Length);

Play sound on button click android

Tested and working 100%

public class MainActivity extends ActionBarActivity {
    Context context = this;
    MediaPlayer mp;

    @Override
    public void onCreate(Bundle savedInstanceState) {
        super.onCreate(savedInstanceState);
        setContentView(R.layout.main_layout);
        mp = MediaPlayer.create(context, R.raw.sound);
        final Button b = (Button) findViewById(R.id.Button);
        b.setOnClickListener(new View.OnClickListener() {
            @Override
            public void onClick(View v) {

                try {
                    if (mp.isPlaying()) {
                        mp.stop();
                        mp.release();
                        mp = MediaPlayer.create(context, R.raw.sound);
                    } mp.start();
                } catch(Exception e) { e.printStackTrace(); }
            }
        });
    }
}

This was all we had to do

if (mp.isPlaying()) {
    mp.stop();
    mp.release();
    mp = MediaPlayer.create(context, R.raw.sound);
}

UIDevice uniqueIdentifier deprecated - What to do now?

NSLog(@"%@",[[UIDevice currentDevice]identifierForVendor]);

TypeScript error: Type 'void' is not assignable to type 'boolean'

It means that the callback function you passed to this.dataStore.data.find should return a boolean and have 3 parameters, two of which can be optional:

  • value: Conversations
  • index: number
  • obj: Conversation[]

However, your callback function does not return anything (returns void). You should pass a callback function with the correct return value:

this.dataStore.data.find((element, index, obj) => {
    // ...

    return true; // or false
});

or:

this.dataStore.data.find(element => {
    // ...

    return true; // or false
});

Reason why it's this way: the function you pass to the find method is called a predicate. The predicate here defines a boolean outcome based on conditions defined in the function itself, so that the find method can determine which value to find.

In practice, this means that the predicate is called for each item in data, and the first item in data for which your predicate returns true is the value returned by find.

How to set Grid row and column positions programmatically

for (int i = 0; i < 6; i++)
{
    test.ColumnDefinitions.Add(new ColumnDefinition());

    Label t1 = new Label();
    t1.Content = "Test" + i;

    Grid.SetColumn(t1, i);
    Grid.SetRow(t1, 0);
    test.Children.Add(t1);
}

matplotlib colorbar in each subplot

This can be easily solved with the the utility make_axes_locatable. I provide a minimal example that shows how this works and should be readily adaptable:

bar to each image

import matplotlib.pyplot as plt
from mpl_toolkits.axes_grid1 import make_axes_locatable

import numpy as np

m1 = np.random.rand(3, 3)
m2 = np.arange(0, 3*3, 1).reshape((3, 3))

fig = plt.figure(figsize=(16, 12))
ax1 = fig.add_subplot(121)
im1 = ax1.imshow(m1, interpolation='None')

divider = make_axes_locatable(ax1)
cax = divider.append_axes('right', size='5%', pad=0.05)
fig.colorbar(im1, cax=cax, orientation='vertical')

ax2 = fig.add_subplot(122)
im2 = ax2.imshow(m2, interpolation='None')

divider = make_axes_locatable(ax2)
cax = divider.append_axes('right', size='5%', pad=0.05)
fig.colorbar(im2, cax=cax, orientation='vertical');

Hyper-V: Create shared folder between host and guest with internal network

Share Files, Folders or Drives Between Host and Hyper-V Virtual Machine

Prerequisites

  1. Ensure that Enhanced session mode settings are enabled on the Hyper-V host.

    Start Hyper-V Manager, and in the Actions section, select "Hyper-V Settings".

    hyper-v-settings

    Make sure that enhanced session mode is allowed in the Server section. Then, make sure that the enhanced session mode is available in the User section.

    use-enhanced-session-mode

  2. Enable Hyper-V Guest Services for your virtual machine

    Right-click on Virtual Machine > Settings. Select the Integration Services in the left-lower corner of the menu. Check Guest Service and click OK.

    enable-guest-services

Steps to share devices with Hyper-v virtual machine:

  1. Start a virtual machine and click Show Options in the pop-up windows.

    connect-to-vm

    Or click "Edit Session Settings..." in the Actions panel on the right

    edit-session-sessions

    It may only appear when you're (able to get) connected to it. If it doesn't appear try Starting and then Connecting to the VM while paying close attention to the panel in the Hyper-V Manager.

  2. View local resources. Then, select the "More..." menu.

    click-more

  3. From there, you can choose which devices to share. Removable drives are especially useful for file sharing.

    choose-the-devices-that-you-want-to-use

  4. Choose to "Save my settings for future connections to this virtual machine".

    save-my-settings-for-future-connections-to-this-vm

  5. Click Connect. Drive sharing is now complete, and you will see the shared drive in this PC > Network Locations section of Windows Explorer after using the enhanced session mode to sigh to the VM. You should now be able to copy files from a physical machine and paste them into a virtual machine, and vice versa.

    shared-drives-from-local-pc

Source (and for more info): Share Files, Folders or Drives Between Host and Hyper-V Virtual Machine

Set height of chart in Chart.js

Just to add on to the answer given by @numediaweb

In case you're banging your head against the wall because after following the instructions to set maintainAspectRatio=false: I originally copied my code from an example I got on a website on using Chart.js with Angular 2+:

        <div style="display: block">
          <canvas baseChart
                  [datasets]="chartData"
                  [labels]="chartLabels"
                  [options]="chartOptions"
                  [legend]="chartLegend"
                  [colors]="chartColors"
                  [chartType]="chartType">
          </canvas>
        </div>

To make this work correctly you must remove the embedded (and unnecessary) style="display: block" Instead define a class for the enclosing div, and define its height in CSS.

Once you do that, the chart should have responsive width but fixed height.

How to count the number of lines of a string in javascript

Here is the working sample fiddle

Just remove additional \r\n and "|" from your reg ex.

'DataFrame' object has no attribute 'sort'

sort() was deprecated for DataFrames in favor of either:

sort() was deprecated (but still available) in Pandas with release 0.17 (2015-10-09) with the introduction of sort_values() and sort_index(). It was removed from Pandas with release 0.20 (2017-05-05).

Multiple definition of ... linker error

Don't define variables in headers. Put declarations in header and definitions in one of the .c files.

In config.h

extern const char *names[];

In some .c file:

const char *names[] =
    {
        "brian", "stefan", "steve"
    };

If you put a definition of a global variable in a header file, then this definition will go to every .c file that includes this header, and you will get multiple definition error because a varible may be declared multiple times but can be defined only once.