Programs & Examples On #Abpeoplepickerview

The ABPeoplePickerView class allows you to customize the behavior of people-picker views in an application’s user interface.

Difference between $(document.body) and $('body')

I have found a pretty big difference in timing when testing in my browser.

I used the following script:

WARNING: running this will freeze your browser a bit, might even crash it.

_x000D_
_x000D_
var n = 10000000, i;_x000D_
i = n;_x000D_
console.time('selector');_x000D_
while (i --> 0){_x000D_
    $("body");_x000D_
}_x000D_
_x000D_
console.timeEnd('selector');_x000D_
_x000D_
i = n;_x000D_
console.time('element');_x000D_
while (i --> 0){_x000D_
    $(document.body);_x000D_
}_x000D_
_x000D_
console.timeEnd('element');
_x000D_
<script src="https://ajax.googleapis.com/ajax/libs/jquery/2.1.1/jquery.min.js"></script>
_x000D_
_x000D_
_x000D_

I did 10 million interactions, and those were the results (Chrome 65):

selector: 19591.97509765625ms
element: 4947.8759765625ms

Passing the element directly is around 4 times faster than passing the selector.

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

Swift 3 Implementation

    import Foundation
class KeyboardStateListener: NSObject
{
    static let shared = KeyboardStateListener()
    var isVisible = false

    func start() {
        NotificationCenter.default.addObserver(self, selector: #selector(didShow), name: NSNotification.Name.UIKeyboardWillShow, object: nil)
        NotificationCenter.default.addObserver(self, selector: #selector(didHide), name: NSNotification.Name.UIKeyboardWillHide, object: nil)
    }

    func didShow()
    {
        isVisible = true
    }

    func didHide()
    {
        isVisible = false
    } 
}

How to trigger a build only if changes happen on particular set of files

I answered this question in another post:

How to get list of changed files since last build in Jenkins/Hudson

#!/bin/bash

set -e

job_name="whatever"
JOB_URL="http://myserver:8080/job/${job_name}/"
FILTER_PATH="path/to/folder/to/monitor"

python_func="import json, sys
obj = json.loads(sys.stdin.read())
ch_list = obj['changeSet']['items']
_list = [ j['affectedPaths'] for j in ch_list ]
for outer in _list:
  for inner in outer:
    print inner
"

_affected_files=`curl --silent ${JOB_URL}${BUILD_NUMBER}'/api/json' | python -c "$python_func"`

if [ -z "`echo \"$_affected_files\" | grep \"${FILTER_PATH}\"`" ]; then
  echo "[INFO] no changes detected in ${FILTER_PATH}"
  exit 0
else
  echo "[INFO] changed files detected: "
  for a_file in `echo "$_affected_files" | grep "${FILTER_PATH}"`; do
    echo "    $a_file"
  done;
fi;

You can add the check directly to the top of the job's exec shell, and it will exit 0 if no changes are detected... Hence, you can always poll the top level for check-in's to trigger a build.

Adding System.Web.Script reference in class library

The ScriptIgnoreAttribute class is in the System.Web.Extensions.dll assembly (Located under Assemblies > Framework in the VS Reference Manager). You have to add a reference to that assembly in your class library project.

You can find this information at top of the MSDN page for the ScriptIgnoreAttribute class.

ini_set("memory_limit") in PHP 5.3.3 is not working at all

Let's do a test with 2 examples:

    <?php    
    $memory = (int)ini_get("memory_limit"); // Display your current value in php.ini (for example: 64M)
    echo "original memory: ".$memory."<br>";
    ini_set('memory_limit','128M'); // Try to override the memory limit for this script
    echo "new memory:".$memory;
    }
    // Will display:
    // original memory: 64
    // new memory: 64
    ?>

The above example doesn't work for overriding the memory_limit value. But This will work:

    <?php
    $memory = (int)ini_get("memory_limit"); // get the current value
    ini_set('memory_limit','128'); // override the value
    echo "original memory: ".$memory."<br>"; // echo the original value
    $new_memory = (int)ini_get("memory_limit"); // get the new value
    echo "new memory: ".$new_memory;  // echo the new value
    // Will display:
    // original memory: 64
    // new memory: 128
    ?>

You have to place the ini_set('memory_limit','128M'); at the top of the file or at least before any echo.

As for me, suhosin wasn't the solution because it doesn't even appear in my phpinfo(), but this worked:

    <?php
    ini_set('memory_limit','2048M'); // set at the top of the file
    (...)
    ?>

Change drawable color programmatically

Syntax

"your image name".setColorFilter("your context".getResources().getColor("color name"));

Example

myImage.setColorFilter(mContext.getResources().getColor(R.color.deep_blue_new));

How does one create an InputStream from a String?

InputStream in = new ByteArrayInputStream(yourstring.getBytes());

jQuery: Performing synchronous AJAX requests

how remote is that url ? is it from the same domain ? the code looks okay

try this

$.ajaxSetup({async:false});
$.get(remote_url, function(data) { remote = data; });
// or
remote = $.get(remote_url).responseText;

Remove a data connection from an Excel 2010 spreadsheet in compatibility mode

I had the same problem today. If after you delete all of the connections, the connection properties still live on. I clicked on properties, deleted the name by selecting the name window and deleting it.

A warning came up to verify I really wanted to do it. After selecting yes, it got rid of the connection. Save the workbook.

I am a hack at Excel but this seemed to work.

Converting a value to 2 decimal places within jQuery

you can use just javascript for it

var total =10.8
(total).toFixed(2); 10.80


alert(total.toFixed(2))); 

Get domain name

If you want specific users to have access to all or part of the WMI object space, you need to permission them as shown here. Note that you have to be running on as an admin to perform this setting.

Assign one struct to another in C

First Look at this example :

The C code for a simple C program is given below

struct Foo {
    char a;
    int b;
    double c;
    } foo1,foo2;

void foo_assign(void)
{
    foo1 = foo2;
}
int main(/*char *argv[],int argc*/)
{
    foo_assign();
return 0;
}

The Equivalent ASM Code for foo_assign() is

00401050 <_foo_assign>:
  401050:   55                      push   %ebp
  401051:   89 e5                   mov    %esp,%ebp
  401053:   a1 20 20 40 00          mov    0x402020,%eax
  401058:   a3 30 20 40 00          mov    %eax,0x402030
  40105d:   a1 24 20 40 00          mov    0x402024,%eax
  401062:   a3 34 20 40 00          mov    %eax,0x402034
  401067:   a1 28 20 40 00          mov    0x402028,%eax
  40106c:   a3 38 20 40 00          mov    %eax,0x402038
  401071:   a1 2c 20 40 00          mov    0x40202c,%eax
  401076:   a3 3c 20 40 00          mov    %eax,0x40203c
  40107b:   5d                      pop    %ebp
  40107c:   c3                      ret    

As you can see that a assignment is simply replaced by a "mov" instruction in assembly, the assignment operator simply means moving data from one memory location to another memory location. The assignment will only do it for immediate members of a structures and will fail to copy when you have Complex datatypes in a structure. Here COMPLEX means that you cant have array of pointers ,pointing to lists.

An array of characters within a structure will itself not work on most compilers, this is because assignment will simply try to copy without even looking at the datatype to be of complex type.

Scroll back to the top of scrollable div

If the html content overflow a single viewport, this worked for me using only javascript:

document.getElementsByTagName('body')[0].scrollTop = 0;

Regards,

How to convert a byte array to Stream

In your case:

MemoryStream ms = new MemoryStream(buffer);

My eclipse won't open, i download the bundle pack it keeps saying error log

Make sure you have the prerequisite, a JVM (http://wiki.eclipse.org/Eclipse/Installation#Install_a_JVM) installed.

This will be a JRE and JDK package.

There are a number of sources which includes: http://www.oracle.com/technetwork/java/javase/downloads/index.html.

How to lowercase a pandas dataframe string column if it has missing values?

use pandas vectorized string methods; as in the documentation:

these methods exclude missing/NA values automatically

.str.lower() is the very first example there;

>>> df['x'].str.lower()
0    one
1    two
2    NaN
Name: x, dtype: object

LINQ: Select where object does not contain items from list

Try this simple LINQ:

//For a file list/array
var files = Directory.GetFiles(folderPath, "*.*", SearchOption.AllDirectories);

//simply use Where ! x.Contains
var notContain = files.Where(x => ! x.Contains(@"\$RECYCLE.BIN\")).ToList();

//Or use Except()
var containing = files.Where(x => x.Contains(@"\$RECYCLE.BIN\")).ToList();
    notContain = files.Except(containing).ToList();

Trying to get property of non-object - CodeIgniter

In my case, I was looping through a series of objects from an XML file, but some of the instances apparently were not objects which was causing the error. Checking if the object was empty before processing it fixed the problem.

In other words, without checking if the object was empty, the script would error out on any empty object with the error as given below.

Trying to get property of non-object

For Example:

if (!empty($this->xml_data->thing1->thing2))
{
   foreach ($this->xml_data->thing1->thing2 as $thing)
   {

   }
}

Argument list too long error for rm, cp, mv commands

I found that for extremely large lists of files (>1e6), these answers were too slow. Here is a solution using parallel processing in python. I know, I know, this isn't linux... but nothing else here worked.

(This saved me hours)

# delete files
import os as os
import glob
import multiprocessing as mp

directory = r'your/directory'
os.chdir(directory)


files_names = [i for i in glob.glob('*.{}'.format('pdf'))]

# report errors from pool

def callback_error(result):
    print('error', result)

# delete file using system command
def delete_files(file_name):
     os.system('rm -rf ' + file_name)

pool = mp.Pool(12)  
# or use pool = mp.Pool(mp.cpu_count())


if __name__ == '__main__':
    for file_name in files_names:
        print(file_name)
        pool.apply_async(delete_files,[file_name], error_callback=callback_error)

Resizable table columns with jQuery

I've done my own jquery ui widget, just thinking if it's good enough.

https://github.com/OnekO/colresizable

Curl GET request with json parameter

This should work :

  curl -i -H "Accept: application/json" 'server:5050/a/c/getName{"param0":"pradeep"}'

use option -i instead of x.

jQuery Event : Detect changes to the html/text of a div

There is no inbuilt solution to this problem, this is a problem with your design and coding pattern.

You can use publisher/subscriber pattern. For this you can use jQuery custom events or your own event mechanism.

First,

function changeHtml(selector, html) {
    var elem = $(selector);
    jQuery.event.trigger('htmlchanging', { elements: elem, content: { current: elem.html(), pending: html} });
    elem.html(html);
    jQuery.event.trigger('htmlchanged', { elements: elem, content: html });
}

Now you can subscribe divhtmlchanging/divhtmlchanged events as follow,

$(document).bind('htmlchanging', function (e, data) {
    //your before changing html, logic goes here
});

$(document).bind('htmlchanged', function (e, data) {
    //your after changed html, logic goes here
});

Now, you have to change your div content changes through this changeHtml() function. So, you can monitor or can do necessary changes accordingly because bind callback data argument containing the information.

You have to change your div's html like this;

changeHtml('#mydiv', '<p>test content</p>');

And also, you can use this for any html element(s) except input element. Anyway you can modify this to use with any element(s).

select count(*) from select

You're missing a FROM and you need to give the subquery an alias.

SELECT COUNT(*) FROM 
(
  SELECT DISTINCT a.my_id, a.last_name, a.first_name, b.temp_val
   FROM dbo.Table_A AS a 
   INNER JOIN dbo.Table_B AS b 
   ON a.a_id = b.a_id
) AS subquery;

jQuery - Get Width of Element when Not Visible (Display: None)

One solution, though it won't work in all situations, is to hide the element by setting the opacity to 0. A completely transparent element will have width.

The draw back is that the element will still take up space, but that won't be an issue in all cases.

For example:

$(img).css("opacity", 0)  //element cannot be seen
width = $(img).width()    //but has width

php form action php self

Another (and in my opinion proper) method is use the __FILE__ constant if you don't like to rely on $_SERVER variables.

$parts = explode(DIRECTORY_SEPARATOR, __FILE__);
$fileName = end($parts);
echo $fileName;

About magic and predefined constants: 1, 2.

Vertical and horizontal align (middle and center) with CSS

There are many methods :

  1. Center horizontal and vertical align of an element with fixed measure

CSS

 <div style="width:200px;height:100px;position:absolute;left:50%;top:50%;
margin-left:-100px;margin-top:-50px;">
<!–content–>
</div> 

2 . Center horizontally and vertically a single line of text

CSS

<div style="width:400px;height:200px;text-align:center;line-height:200px;">
<!–content–>
</div>  

3 . Center horizontal and vertical align of an element with no specific measure

CSS

<div style="display:table;height:300px;text-align:center;">
<div style="display:table-cell;vertical-align:middle;">
<!–content–>
</div>
</div>  

IntelliJ - Convert a Java project/module into a Maven project/module

  1. Open 'Maven projects' (tab on the right side).
  2. Use 'Add Maven Projects'
  3. Find your pom.xml

Div Size Automatically size of content

The best way to do this is to set display: inline;. Note, however, that in inline display, you lose access to some layout properties, such as manual height and vertical margins, but this doesn't appear to be a problem for your page.

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

Python: import cx_Oracle ImportError: No module named cx_Oracle error is thown

I had a similar problem, you gotta make sure you have:

  1. oracle instant client
  2. cx_Oracle binary( from SourceForge )
  3. Python IMPORTANT: Make sure they are ALL either 64-bit or 32-bit, mixing is gonna cause problems

What's the difference between "Request Payload" vs "Form Data" as seen in Chrome dev tools Network tab

The Request Payload - or to be more precise: payload body of a HTTP Request - is the data normally send by a POST or PUT Request. It's the part after the headers and the CRLF of a HTTP Request.

A request with Content-Type: application/json may look like this:

POST /some-path HTTP/1.1
Content-Type: application/json

{ "foo" : "bar", "name" : "John" }

If you submit this per AJAX the browser simply shows you what it is submitting as payload body. That’s all it can do because it has no idea where the data is coming from.

If you submit a HTML-Form with method="POST" and Content-Type: application/x-www-form-urlencoded or Content-Type: multipart/form-data your request may look like this:

POST /some-path HTTP/1.1
Content-Type: application/x-www-form-urlencoded

foo=bar&name=John

In this case the form-data is the request payload. Here the Browser knows more: it knows that bar is the value of the input-field foo of the submitted form. And that’s what it is showing to you.

So, they differ in the Content-Type but not in the way data is submitted. In both cases the data is in the message-body. And Chrome distinguishes how the data is presented to you in the Developer Tools.

hibernate - get id after save object

Let's say your primary key is an Integer and the object you save is "ticket", then you can get it like this. When you save the object, a Serializable id is always returned

Integer id = (Integer)session.save(ticket);

How to convert php array to utf8?

You can use string utf8_encode( string $data ) function to accomplish what you want. It is for a single string. You can write your own function using which you can convert an array with the help of utf8_encode function.

How to call an element in a numpy array?

Use numpy. array. flatten() to convert a 2D NumPy array into a 1D array print(array_2d) array_1d = array_2d. flatten() flatten array_2d print(array_1d)

How to select multiple files with <input type="file">?

You can do it now with HTML5

In essence you use the multiple attribute on the file input.

<input type='file' multiple>

HTML <select> selected option background-color CSS style

<select name=protect_email size=1 style="background: #009966; color: #FFF;" onChange="this.style.backgroundColor=this.options[this.selectedIndex].style.backgroundColor">    
<option value=0 style="background: #009966; color: #FFF;" selected>Protect my email</option>;  
<option value=1 style="background: #FF0000; color: #FFF;">Show email on advert</option>;
</select>; 

http://pro.org.uk/classified/Directory?act=book&category=120

Tested it in FF,Opera,Konqueror worked fine...

How Should I Declare Foreign Key Relationships Using Code First Entity Framework (4.1) in MVC3?

If you have an Order class, adding a property that references another class in your model, for instance Customer should be enough to let EF know there's a relationship in there:

public class Order
{
    public int ID { get; set; }

    // Some other properties

    // Foreign key to customer
    public virtual Customer Customer { get; set; }
}

You can always set the FK relation explicitly:

public class Order
{
    public int ID { get; set; }

    // Some other properties

    // Foreign key to customer
    [ForeignKey("Customer")]
    public string CustomerID { get; set; }
    public virtual Customer Customer { get; set; }
}

The ForeignKeyAttribute constructor takes a string as a parameter: if you place it on a foreign key property it represents the name of the associated navigation property. If you place it on the navigation property it represents the name of the associated foreign key.

What this means is, if you where to place the ForeignKeyAttribute on the Customer property, the attribute would take CustomerID in the constructor:

public string CustomerID { get; set; }
[ForeignKey("CustomerID")]
public virtual Customer Customer { get; set; }

EDIT based on Latest Code You get that error because of this line:

[ForeignKey("Parent")]
public Patient Patient { get; set; }

EF will look for a property called Parent to use it as the Foreign Key enforcer. You can do 2 things:

1) Remove the ForeignKeyAttribute and replace it with the RequiredAttribute to mark the relation as required:

[Required]
public virtual Patient Patient { get; set; }

Decorating a property with the RequiredAttribute also has a nice side effect: The relation in the database is created with ON DELETE CASCADE.

I would also recommend making the property virtual to enable Lazy Loading.

2) Create a property called Parent that will serve as a Foreign Key. In that case it probably makes more sense to call it for instance ParentID (you'll need to change the name in the ForeignKeyAttribute as well):

public int ParentID { get; set; }

In my experience in this case though it works better to have it the other way around:

[ForeignKey("Patient")]
public int ParentID { get; set; }

public virtual Patient Patient { get; set; }

mysql query result in php variable

$query    =    "SELECT username, userid FROM user WHERE username = 'admin' ";
$result    =    $conn->query($query);

if (!$result) {
  echo 'Could not run query: ' . mysql_error();
  exit;
}

$arrayResult    =    mysql_fetch_array($result);

//Now you can access $arrayResult like this

$arrayResult['userid'];    // output will be userid which will be in database
$arrayResult['username'];  // output will be admin

//Note- userid and username will be column name of user table.

Importing a csv into mysql via command line

try this:

mysql -uusername -ppassword --local-infile scrapping -e "LOAD DATA LOCAL INFILE 'CSVname.csv'  INTO TABLE table_name  FIELDS TERMINATED BY ',' LINES TERMINATED BY '\n'"

How do I convert an interval into a number of hours with postgres?

To get the number of days the easiest way would be:

SELECT EXTRACT(DAY FROM NOW() - '2014-08-02 08:10:56');

As far as I know it would return the same as:

SELECT (EXTRACT(epoch FROM (SELECT (NOW() - '2014-08-02 08:10:56')))/86400)::int;

display html page with node.js

Check this basic code to setup html server. its work for me.

var http = require('http'),
    fs = require('fs');


fs.readFile('./index.html', function (err, html) {
    if (err) {
        throw err; 
    }       
    http.createServer(function(request, response) {  
        response.writeHeader(200, {"Content-Type": "text/html"});  
        response.write(html);  
        response.end();  
    }).listen(8000);
});

How to convert milliseconds to "hh:mm:ss" format?

Well, you could try something like this, :

public String getElapsedTimeHoursMinutesSecondsString() {       
     long elapsedTime = getElapsedTime();  
     String format = String.format("%%0%dd", 2);  
     elapsedTime = elapsedTime / 1000;  
     String seconds = String.format(format, elapsedTime % 60);  
     String minutes = String.format(format, (elapsedTime % 3600) / 60);  
     String hours = String.format(format, elapsedTime / 3600);  
     String time =  hours + ":" + minutes + ":" + seconds;  
     return time;  
 }  

to convert milliseconds to a time value

Program to find prime numbers

One line code in C# :-

Console.WriteLine(String.Join(Environment.NewLine, 
    Enumerable.Range(2, 300)
        .Where(n => Enumerable.Range(2, (int)Math.Sqrt(n) - 1)
        .All(nn => n % nn != 0)).ToArray()));                                    

Checking if a file is a directory or just a file

Normally you want to perform this check atomically with using the result, so stat() is useless. Instead, open() the file read-only first and use fstat(). If it's a directory, you can then use fdopendir() to read it. Or you can try opening it for writing to begin with, and the open will fail if it's a directory. Some systems (POSIX 2008, Linux) also have an O_DIRECTORY extension to open which makes the call fail if the name is not a directory.

Your method with opendir() is also good if you want a directory, but you should not close it afterwards; you should go ahead and use it.

subsetting a Python DataFrame

I'll assume that Time and Product are columns in a DataFrame, df is an instance of DataFrame, and that other variables are scalar values:

For now, you'll have to reference the DataFrame instance:

k1 = df.loc[(df.Product == p_id) & (df.Time >= start_time) & (df.Time < end_time), ['Time', 'Product']]

The parentheses are also necessary, because of the precedence of the & operator vs. the comparison operators. The & operator is actually an overloaded bitwise operator which has the same precedence as arithmetic operators which in turn have a higher precedence than comparison operators.

In pandas 0.13 a new experimental DataFrame.query() method will be available. It's extremely similar to subset modulo the select argument:

With query() you'd do it like this:

df[['Time', 'Product']].query('Product == p_id and Month < mn and Year == yr')

Here's a simple example:

In [9]: df = DataFrame({'gender': np.random.choice(['m', 'f'], size=10), 'price': poisson(100, size=10)})

In [10]: df
Out[10]:
  gender  price
0      m     89
1      f    123
2      f    100
3      m    104
4      m     98
5      m    103
6      f    100
7      f    109
8      f     95
9      m     87

In [11]: df.query('gender == "m" and price < 100')
Out[11]:
  gender  price
0      m     89
4      m     98
9      m     87

The final query that you're interested will even be able to take advantage of chained comparisons, like this:

k1 = df[['Time', 'Product']].query('Product == p_id and start_time <= Time < end_time')

"The file "MyApp.app" couldn't be opened because you don't have permission to view it" when running app in Xcode 6 Beta 4

I fixed this myself switching between "arm32" and "arm64" architectures. From the "Build Settings", I modified "Architectures" and "Valid Architectures" from "arm32" to "arm64" and it worked. After changing a number of other settings, switching between arm32 and arm64 no longer makes a difference, so I'm skeptical if this was the route cause.

Previously I tried all the other suggestions here:

  • plist was unmodified
  • EXECUTIBLE_NAME was unmodified
  • Build Clean
  • Delete DerivedData
  • Default Compiler

How do I to insert data into an SQL table using C# as well as implement an upload function?

You should use parameters in your query to prevent attacks, like if someone entered '); drop table ArticlesTBL;--' as one of the values.

string query = "INSERT INTO ArticlesTBL (ArticleTitle, ArticleContent, ArticleType, ArticleImg, ArticleBrief,  ArticleDateTime, ArticleAuthor, ArticlePublished, ArticleHomeDisplay, ArticleViews)";
query += " VALUES (@ArticleTitle, @ArticleContent, @ArticleType, @ArticleImg, @ArticleBrief, @ArticleDateTime, @ArticleAuthor, @ArticlePublished, @ArticleHomeDisplay, @ArticleViews)";

SqlCommand myCommand = new SqlCommand(query, myConnection);
myCommand.Parameters.AddWithValue("@ArticleTitle", ArticleTitleTextBox.Text);
myCommand.Parameters.AddWithValue("@ArticleContent", ArticleContentTextBox.Text);
// ... other parameters
myCommand.ExecuteNonQuery();

Exploits of a Mom

(xkcd)

Chart.js v2 - hiding grid lines

options: {
    scales: {
        xAxes: [{
            gridLines: {
                drawOnChartArea: false
            }
        }],
        yAxes: [{
            gridLines: {
                drawOnChartArea: false
            }
        }]
    }
}

Visual Studio Code - Target of URI doesn't exist 'package:flutter/material.dart'

I didn't think this was possible: I had to delete flutter folder and reinstall it from scratch!

Are SSL certificates bound to the servers ip address?

SSL certificates are bound to a 'common name', which is usually a fully qualified domain name but can be a wildcard name (eg. *.domain.com) or even an IP address, but it usually isn't.

In your case, you are accessing your LDAP server by a hostname and it sounds like your two LDAP servers have different SSL certificates installed. Are you able to view (or download and view) the details of the SSL certificate? Each SSL certificate will have a unique serial numbers and fingerprint which will need to match. I assume the certificate is being rejected as these details don't match with what's in your certificate store.

Your solution will be to ensure that both LDAP servers have the same SSL certificate installed.

BTW - you can normally override DNS entries on your workstation by editing a local 'hosts' file, but I wouldn't recommend this.

How to read a text file into a list or an array with Python

So you want to create a list of lists... We need to start with an empty list

list_of_lists = []

next, we read the file content, line by line

with open('data') as f:
    for line in f:
        inner_list = [elt.strip() for elt in line.split(',')]
        # in alternative, if you need to use the file content as numbers
        # inner_list = [int(elt.strip()) for elt in line.split(',')]
        list_of_lists.append(inner_list)

A common use case is that of columnar data, but our units of storage are the rows of the file, that we have read one by one, so you may want to transpose your list of lists. This can be done with the following idiom

by_cols = zip(*list_of_lists)

Another common use is to give a name to each column

col_names = ('apples sold', 'pears sold', 'apples revenue', 'pears revenue')
by_names = {}
for i, col_name in enumerate(col_names):
    by_names[col_name] = by_cols[i]

so that you can operate on homogeneous data items

 mean_apple_prices = [money/fruits for money, fruits in
                     zip(by_names['apples revenue'], by_names['apples_sold'])]

Most of what I've written can be speeded up using the csv module, from the standard library. Another third party module is pandas, that lets you automate most aspects of a typical data analysis (but has a number of dependencies).


Update While in Python 2 zip(*list_of_lists) returns a different (transposed) list of lists, in Python 3 the situation has changed and zip(*list_of_lists) returns a zip object that is not subscriptable.

If you need indexed access you can use

by_cols = list(zip(*list_of_lists))

that gives you a list of lists in both versions of Python.

On the other hand, if you don't need indexed access and what you want is just to build a dictionary indexed by column names, a zip object is just fine...

file = open('some_data.csv')
names = get_names(next(file))
columns = zip(*((x.strip() for x in line.split(',')) for line in file)))
d = {}
for name, column in zip(names, columns): d[name] = column

How to create tar.gz archive file in Windows?

tar.gz file is just a tar file that's been gzipped. Both tar and gzip are available for windows.

If you like GUIs (Graphical user interface), 7zip can pack with both tar and gzip.

C++ Object Instantiation

Well, the reason to use the pointer would be exactly the same that the reason to use pointers in C allocated with malloc: if you want your object to live longer than your variable!

It is even highly recommended to NOT use the new operator if you can avoid it. Especially if you use exceptions. In general it is much safer to let the compiler free your objects.

Calculate last day of month in JavaScript

This will give you current month first and last day.

If you need to change 'year' remove d.getFullYear() and set your year.

If you need to change 'month' remove d.getMonth() and set your year.

_x000D_
_x000D_
var d = new Date();_x000D_
var days = ["Sunday", "Monday", "Tuesday", "Wednesday", "Thursday", "Friday", "Saturday"];_x000D_
var fistDayOfMonth = days[(new Date(d.getFullYear(), d.getMonth(), 1).getDay())];_x000D_
 var LastDayOfMonth = days[(new Date(d.getFullYear(), d.getMonth() + 1, 0).getDay())]; _x000D_
console.log("First Day :" + fistDayOfMonth); _x000D_
console.log("Last Day:" + LastDayOfMonth);_x000D_
alert("First Day :" + fistDayOfMonth); _x000D_
alert("Last Day:" + LastDayOfMonth);
_x000D_
_x000D_
_x000D_

Subprocess check_output returned non-zero exit status 1

For Windows users: Try deleting files: java.exe, javaw.exe and javaws.exe from Windows\System32

My issue was the java version 1.7 installed.

oracle varchar to number

If you want formated number then use

SELECT TO_CHAR(number, 'fmt')
   FROM DUAL;

SELECT TO_CHAR('123', 999.99)
   FROM DUAL;

Result 123.00

How do I POST a x-www-form-urlencoded request using Fetch?

You can use react-native-easy-app that is easier to send http request and formulate interception request.

import { XHttp } from 'react-native-easy-app';

* Synchronous request
const params = {name:'rufeng',age:20}
const response = await XHttp().url(url).param(params).formEncoded().execute('GET');
const {success, json, message, status} = response;


* Asynchronous requests
XHttp().url(url).param(params).formEncoded().get((success, json, message, status)=>{
    if (success){
       this.setState({content: JSON.stringify(json)});
    } else {
       showToast(msg);
    }
});

How do I install Eclipse with C++ in Ubuntu 12.10 (Quantal Quetzal)?

http://www.eclipse.org/cdt/ ^Give that a try

I have not used the CDT for eclipse but I do use Eclipse Java for Ubuntu 12.04 and it works wonders.

How to set custom ActionBar color / style?

For Android 3.0 and higher only

When supporting Android 3.0 and higher only, you can define the action bar's background like this:

res/values/themes.xml

<?xml version="1.0" encoding="utf-8"?>
<resources>
    <!-- the theme applied to the application or activity -->
    <style name="CustomActionBarTheme" parent="@style/Theme.Holo.Light.DarkActionBar">
       <item name="android:actionBarStyle">@style/MyActionBar</item>
    </style>

<!-- ActionBar styles -->
  <style name="MyActionBar" parent="@style/Widget.Holo.Light.ActionBar.Solid.Inverse">
       <item name="android:background">#ff0000</item>
  </style>
</resources>

For Android 2.1 and higher

When using the Support Library, your style XML file might look like this:

<?xml version="1.0" encoding="utf-8"?>
  <resources>
  <!-- the theme applied to the application or activity -->
 <style name="CustomActionBarTheme" parent="@style/Theme.AppCompat.Light.DarkActionBar">
    <item name="android:actionBarStyle">@style/MyActionBar</item>

    <!-- Support library compatibility -->
    <item name="actionBarStyle">@style/MyActionBar</item>
</style>

<!-- ActionBar styles -->
<style name="MyActionBar"
       parent="@style/Widget.AppCompat.Light.ActionBar.Solid.Inverse">
    <item name="android:background">@drawable/actionbar_background</item>

    <!-- Support library compatibility -->
    <item name="background">@drawable/actionbar_background</item>
  </style>
 </resources>

Then apply your theme to your entire app or individual activities:

for more details Documentaion

How do I save a String to a text file using Java?

If you wish to keep the carriage return characters from the string into a file here is an code example:

    jLabel1 = new JLabel("Enter SQL Statements or SQL Commands:");
    orderButton = new JButton("Execute");
    textArea = new JTextArea();
    ...


    // String captured from JTextArea()
    orderButton.addActionListener(new ActionListener() {
        public void actionPerformed(ActionEvent ae) {
            // When Execute button is pressed
            String tempQuery = textArea.getText();
            tempQuery = tempQuery.replaceAll("\n", "\r\n");
            try (PrintStream out = new PrintStream(new FileOutputStream("C:/Temp/tempQuery.sql"))) {
                out.print(tempQuery);
            } catch (FileNotFoundException e) {
                // TODO Auto-generated catch block
                e.printStackTrace();
            }
            System.out.println(tempQuery);
        }

    });

a tag as a submit button?

Try something like below

 <a href="#" onclick="this.forms['formName'].submit()">Submit</a> 

Strings in C, how to get subString

char largeSrt[] = "123456789-123";  // original string

char * substr;
substr = strchr(largeSrt, '-');     // we save the new string "-123"
int substringLength = strlen(largeSrt) - strlen(substr); // 13-4=9 (bigger string size) - (new string size) 

char *newStr = malloc(sizeof(char) * substringLength + 1);// keep memory free to new string
strcpy(newStr, largeSrt, substringLength);  // copy only 9 characters 
newStr[substringLength] = '\0'; // close the new string with final character

printf("newStr=%s\n", newStr);

free(newStr);   // you free the memory 

Saving an image in OpenCV

In my experience OpenCV writes a black image when SaveImage is given a matrix with bit depth different from 8 bit. In fact, this is sort of documented:

Only 8-bit single-channel or 3-channel (with ‘BGR’ channel order) images can be saved using this function. If the format, depth or channel order is different, use cvCvtScale and cvCvtColor to convert it before saving, or use universal cvSave to save the image to XML or YAML format.

In your case you may first investigate what kind of image is captured, change capture properties (I suppose CV_CAP_PROP_CONVERT_RGB might be important) or convert it manually afterwards.

This is an example how to convert to 8-bit representation with OpenCV. cc here is an original matrix of type CV_32FC1, cc8u is its scaled version which is actually written by SaveImage:

# I want to save cc here
cc8u = CreateMat(cc.rows, cc.cols, CV_8U)
ccmin,ccmax,minij,maxij = MinMaxLoc(cc)
ccscale, ccshift = 255.0/(ccmax-ccmin), -ccmin
CvtScale(cc, cc8u, ccscale, ccshift)
SaveImage("cc.png", cc8u)

(sorry, this is Python code, but it should be easy to translate it to C/C++)

How to connect Robomongo to MongoDB

Note: Commenting out bind_ip can make your system vulnerable to security flaws. Please see Security Checklist. It is a better idea to add more IP addresses than to open up your system to everything.

You need to edit your /etc/mongod.conf file's bind_ip variable to include the IP of the computer you're using, or eliminate it altogether.

I was able to connect using the following mongod.conf file. I commented out bind_ip and uncommented port.

# mongod.conf

# Where to store the data.

# Note: if you run MongoDB as a non-root user (recommended) you may
# need to create and set permissions for this directory manually.
# E.g., if the parent directory isn't mutable by the MongoDB user.

dbpath=/var/lib/mongodb

# Where to log
logpath=/var/log/mongodb/mongod.log

logappend=true

port = 27017

# Listen to local interface only. Comment out to listen on all
interfaces.

#bind_ip = 127.0.0.1


# Disables write-ahead journaling
# nojournal = true

# Enables periodic logging of CPU utilization and I/O wait
#cpu = true

# Turn on/off security.  Off is currently the default
#noauth = true

#auth = true

# Verbose logging output.
#verbose = true

# Inspect all client data for validity on receipt (useful for
# developing drivers)
#objcheck = true

# Enable db quota management
#quota = true

# Set oplogging level where n is
#   0=off (default)
#   1=W
#   2=R
#   3=both
#   7=W+some reads
#diaglog = 0

# Ignore query hints
#nohints = true

# Enable the HTTP interface (Defaults to port 28017).
#httpinterface = true

# Turns off server-side scripting.  This will result in greatly limited
# functionality
#noscripting = true

# Turns off table scans.  Any query that would do a table scan fails.
#notablescan = true

# Disable data file preallocation.
#noprealloc = true

# Specify .ns file size for new databases.
# nssize = <size>

# Replication Options
# In replicated MongoDB databases, specify the replica set name here
#replSet=setname

# Maximum size in megabytes for replication operation log
#oplogSize=1024

# Path to a key file storing authentication info for connections
# between replica set members
#keyFile=/path/to/keyfile

Don't forget to restart the mongod service before trying to connect:

service mongod restart

From Robomongo, I used the following connection settings:

Connection Tab:

  • Address: [VPS IP] : 27017

SSH Tab:

  • SSH Address: [VPS IP] : 22

  • SSH User Name: [Username for sudo enabled user]

  • SSH Auth Method: Password

  • User Password: Supersecret

How can I get a precise time, for example in milliseconds in Objective-C?

You can get current time in milliseconds since January 1st, 1970 using an NSDate:

- (double)currentTimeInMilliseconds {
    NSDate *date = [NSDate date];
    return [date timeIntervalSince1970]*1000;
}

Open a link in browser with java button?

A solution without the Desktop environment is BrowserLauncher2. This solution is more general as on Linux, Desktop is not always available.

The lenghty answer is posted at https://stackoverflow.com/a/21676290/873282

Doctrine findBy 'does not equal'

There is now a an approach to do this, using Doctrine's Criteria.

A full example can be seen in How to use a findBy method with comparative criteria, but a brief answer follows.

use \Doctrine\Common\Collections\Criteria;

// Add a not equals parameter to your criteria
$criteria = new Criteria();
$criteria->where(Criteria::expr()->neq('prize', 200));

// Find all from the repository matching your criteria
$result = $entityRepository->matching($criteria);

java.lang.RuntimeException: com.android.builder.dexing.DexArchiveMergerException: Unable to merge dex in Android Studio 3.0

Enable Multidex through build.gradle of your app module

multiDexEnabled true

Same as below -

android {
    compileSdkVersion 27
    defaultConfig {
        applicationId "com.xx.xxx"
        minSdkVersion 15
        targetSdkVersion 27
        versionCode 1
        versionName "1.0"
        multiDexEnabled true //Add this
        testInstrumentationRunner "android.support.test.runner.AndroidJUnitRunner"
    }
    buildTypes {
        release {
            shrinkResources true
            minifyEnabled true
            proguardFiles getDefaultProguardFile('proguard-android-optimize.txt'), 'proguard-rules.pro'
        }
    }
}

Then follow below steps -

  1. From the Build menu -> press the Clean Project button.
  2. When task completed, press the Rebuild Project button from the Build menu.
  3. From menu File -> Invalidate cashes / Restart

compile is now deprecated so it's better to use implementation or api

How to run Rake tasks from within Rake tasks?

task :invoke_another_task do
  # some code
  Rake::Task["another:task"].invoke
end

How to animate button in android?

Dependency

Add it in your root build.gradle at the end of repositories:

allprojects {
repositories {
    ...
    maven { url "https://jitpack.io" }
}}

and then add dependency dependencies { compile 'com.github.varunest:sparkbutton:1.0.5' }

Usage

XML

<com.varunest.sparkbutton.SparkButton
        android:id="@+id/spark_button"
        android:layout_width="40dp"
        android:layout_height="40dp"
        app:sparkbutton_activeImage="@drawable/active_image"
        app:sparkbutton_inActiveImage="@drawable/inactive_image"
        app:sparkbutton_iconSize="40dp"
        app:sparkbutton_primaryColor="@color/primary_color"
        app:sparkbutton_secondaryColor="@color/secondary_color" />

Java (Optional)

SparkButton button  = new SparkButtonBuilder(context)
            .setActiveImage(R.drawable.active_image)
            .setInActiveImage(R.drawable.inactive_image)
            .setDisabledImage(R.drawable.disabled_image)
            .setImageSizePx(getResources().getDimensionPixelOffset(R.dimen.button_size))
            .setPrimaryColor(ContextCompat.getColor(context, R.color.primary_color))
            .setSecondaryColor(ContextCompat.getColor(context, R.color.secondary_color))
            .build();

How can I use std::maps with user-defined types as key?

By default std::map (and std::set) use operator< to determine sorting. Therefore, you need to define operator< on your class.

Two objects are deemed equivalent if !(a < b) && !(b < a).

If, for some reason, you'd like to use a different comparator, the third template argument of the map can be changed, to std::greater, for example.

Undo working copy modifications of one file in Git?

I have Done through git bash:

(use "git checkout -- <file>..." to discard changes in working directory)

  1. Git status. [So we have seen one file wad modified.]
  2. git checkout -- index.html [i have changed in index.html file :
  3. git status [now those changes was removed]

enter image description here

How to find files recursively by file type and copy them to a directory while in ssh?

Try this:

find . -name "*.pdf" -type f -exec cp {} ./pdfsfolder \;

How to run Gradle from the command line on Mac bash

./gradlew

Your directory with gradlew is not included in the PATH, so you must specify path to the gradlew. . means "current directory".

Performance of FOR vs FOREACH in PHP

It's 2020 and stuffs had greatly evolved with php 7.4 and opcache.

Here is the OP^ benchmark, ran as unix CLI, without the echo and html parts.

Test ran locally on a regular computer.

php -v

PHP 7.4.6 (cli) (built: May 14 2020 10:02:44) ( NTS )

Modified benchmark script:

<?php 
 ## preperations; just a simple environment state

  $test_iterations = 100;
  $test_arr_size = 1000;

  // a shared function that makes use of the loop; this should
  // ensure no funny business is happening to fool the test
  function test($input)
  {
    //echo '<!-- '.trim($input).' -->';
  }

  // for each test we create a array this should avoid any of the
  // arrays internal representation or optimizations from getting
  // in the way.

  // normal array
  $test_arr1 = array();
  $test_arr2 = array();
  $test_arr3 = array();
  // hash tables
  $test_arr4 = array();
  $test_arr5 = array();

  for ($i = 0; $i < $test_arr_size; ++$i)
  {
    mt_srand();
    $hash = md5(mt_rand());
    $key = substr($hash, 0, 5).$i;

    $test_arr1[$i] = $test_arr2[$i] = $test_arr3[$i] = $test_arr4[$key] = $test_arr5[$key]
      = $hash;
  }

  ## foreach

  $start = microtime(true);
  for ($j = 0; $j < $test_iterations; ++$j)
  {
    foreach ($test_arr1 as $k => $v)
    {
      test($v);
    }
  }
  echo 'foreach '.(microtime(true) - $start)."\n";  

  ## foreach (using reference)

  $start = microtime(true);
  for ($j = 0; $j < $test_iterations; ++$j)
  {
    foreach ($test_arr2 as &$value)
    {
      test($value);
    }
  }
  echo 'foreach (using reference) '.(microtime(true) - $start)."\n";

  ## for

  $start = microtime(true);
  for ($j = 0; $j < $test_iterations; ++$j)
  {
    $size = count($test_arr3);
    for ($i = 0; $i < $size; ++$i)
    {
      test($test_arr3[$i]);
    }
  }
  echo 'for '.(microtime(true) - $start)."\n";  

  ## foreach (hash table)

  $start = microtime(true);
  for ($j = 0; $j < $test_iterations; ++$j)
  {
    foreach ($test_arr4 as $k => $v)
    {
      test($v);
    }
  }
  echo 'foreach (hash table) '.(microtime(true) - $start)."\n";

  ## for (hash table)

  $start = microtime(true);
  for ($j = 0; $j < $test_iterations; ++$j)
  {
    $keys = array_keys($test_arr5);
    $size = sizeOf($test_arr5);
    for ($i = 0; $i < $size; ++$i)
    {
      test($test_arr5[$keys[$i]]);
    }
  }
  echo 'for (hash table) '.(microtime(true) - $start)."\n";

Output:

foreach 0.0032877922058105
foreach (using reference) 0.0029420852661133
for 0.0025191307067871
foreach (hash table) 0.0035080909729004
for (hash table) 0.0061779022216797

As you can see the evolution is insane, about 560 time faster than reported in 2012.

On my machines and servers, following my numerous experiments, basics for loops are the fastest. This is even clearer using nested loops ($i $j $k..)

It is also the most flexible in usage, and has a better readability from my view.

Using jQuery, Restricting File Size Before Uploading

Try below code:

var sizeInKB = input.files[0].size/1024; //Normally files are in bytes but for KB divide by 1024 and so on
var sizeLimit= 30;

if (sizeInKB >= sizeLimit) {
    alert("Max file size 30KB");
    return false;
}

Passing bash variable to jq

I know is a bit later to reply, sorry. But that works for me.

export K8S_public_load_balancer_url="$(kubectl get services -n ${TENANT}-production -o wide | grep "ingress-nginx-internal$" | awk '{print $4}')"

And now I am able to fetch and pass the content of the variable to jq

export TF_VAR_public_load_balancer_url="$(aws elbv2 describe-load-balancers --region eu-west-1 | jq -r '.LoadBalancers[] | select (.DNSName == "'$K8S_public_load_balancer_url'") | .LoadBalancerArn')"

In my case I needed to use double quote and quote to access the variable value.

Cheers.

CSS property to pad text inside of div

Just use div { padding: 20px; } and substract 40px from your original div width.

Like Philip Wills pointed out, you can also use box-sizing instead of substracting 40px:

div {
    padding: 20px;
    -moz-box-sizing: border-box; 
    box-sizing: border-box;
}

The -moz-box-sizing is for Firefox.

Class file for com.google.android.gms.internal.zzaja not found

Do not mix 12 and 15, use this

implementation 'com.google.firebase:firebase-core:16.0.0'
implementation 'com.google.firebase:firebase-auth:16.0.1'
implementation 'com.google.firebase:firebase-messaging:17.0.0'

How to set border's thickness in percentages?

You can also use

border-left: 9vw solid #F5E5D6;
border-right: 9vw solid #F5E5D6;     

OR

border: 9vw solid #F5E5D6;

Using OpenSSL what does "unable to write 'random state'" mean?

Apparently, I needed to run OpenSSL as root in order for it to have permission to the seeding file.

How do you run a command as an administrator from the Windows command line?

Simple pipe trick, ||, with some .vbs used at top of your batch. It will exit regular and restart as administrator.

@AT>NUL||echo set shell=CreateObject("Shell.Application"):shell.ShellExecute "%~dpnx0",,"%CD%", "runas", 1:set shell=nothing>%~n0.vbs&start %~n0.vbs /realtime& timeout 1 /NOBREAK>nul& del /Q %~n0.vbs&cls&exit

It also del /Q the temp.vbs when it's done using it.

How to stop/shut down an elasticsearch node?

Considering you have 3 nodes.

Prepare your cluster

export ES_HOST=localhost:9200

# Disable shard allocation
curl -X PUT "$ES_HOST/_cluster/settings" -H 'Content-Type: application/json' -d'
{
  "persistent": {
    "cluster.routing.allocation.enable": "none"
  }
}
'

# Stop non-essential indexing and perform a synced flush
curl -X POST "$ES_HOST/_flush/synced"

Stop elasticsearch service in each node

# check nodes
export ES_HOST=localhost:9200
curl -X GET "$ES_HOST/_cat/nodes"

# node 1
systemctl stop elasticsearch.service

# node 2
systemctl stop elasticsearch.service

# node 3
systemctl stop elasticsearch.service

Restarting cluster again

# start
systemctl start elasticsearch.service

# Reenable shard allocation once the node has joined the cluster
curl -X PUT "$ES_HOST/_cluster/settings" -H 'Content-Type: application/json' -d'
{
  "persistent": {
    "cluster.routing.allocation.enable": null
  }
}
'

Tested on Elasticseach 6.5

Source:

  1. https://www.elastic.co/guide/en/elasticsearch/reference/6.5/stopping-elasticsearch.html
  2. https://www.elastic.co/guide/en/elasticsearch/reference/6.5/rolling-upgrades.html

Keep CMD open after BAT file executes

If you are starting the script within the command line, then add exit /b to keep CMD opened

Include an SVG (hosted on GitHub) in MarkDown

rawgit.com solves this problem nicely. For each request, it retrieves the appropriate document from GitHub and, crucially, serves it with the correct Content-Type header.

How to solve "Could not establish trust relationship for the SSL/TLS secure channel with authority"

This occurred when trying to connect to the WCF Service via. the IP e.g. https://111.11.111.1:port/MyService.svc while using a certificate tied to a name e.g. mysite.com.

Switching to the https://mysite.com:port/MyService.svc resolved it.

How to close a Java Swing application from the code

I guess a EXIT_ON_CLOSE

frame.setDefaultCloseOperation(JFrame.EXIT_ON_CLOSE);

before System.exit(0) is better since you can write a Window Listener to make some cleaning operations before actually leaving the app.

That window listener allows you to defined:

public void windowClosing(WindowEvent e) {
    displayMessage("WindowListener method called: windowClosing.");
    //A pause so user can see the message before
    //the window actually closes.
    ActionListener task = new ActionListener() {
        boolean alreadyDisposed = false;
        public void actionPerformed(ActionEvent e) {
            if (frame.isDisplayable()) {
                alreadyDisposed = true;
                frame.dispose();
            }
        }
    };
    Timer timer = new Timer(500, task); //fire every half second
    timer.setInitialDelay(2000);        //first delay 2 seconds
    timer.setRepeats(false);
    timer.start();
}

public void windowClosed(WindowEvent e) {
    //This will only be seen on standard output.
    displayMessage("WindowListener method called: windowClosed.");
}

Auto Scale TextView Text to Fit within Bounds

I just created the following method (based on the ideas of Chase) which might help you if you want to draw text to any canvas:

private static void drawText(Canvas canvas, int xStart, int yStart,
        int xWidth, int yHeigth, String textToDisplay,
        TextPaint paintToUse, float startTextSizeInPixels,
        float stepSizeForTextSizeSteps) {

    // Text view line spacing multiplier
    float mSpacingMult = 1.0f;
    // Text view additional line spacing
    float mSpacingAdd = 0.0f;
    StaticLayout l = null;
    do {
        paintToUse.setTextSize(startTextSizeInPixels);
        startTextSizeInPixels -= stepSizeForTextSizeSteps;
        l = new StaticLayout(textToDisplay, paintToUse, xWidth,
                Alignment.ALIGN_NORMAL, mSpacingMult, mSpacingAdd, true);
    } while (l.getHeight() > yHeigth);

    int textCenterX = xStart + (xWidth / 2);
    int textCenterY = (yHeigth - l.getHeight()) / 2;

    canvas.save();
    canvas.translate(textCenterX, textCenterY);
    l.draw(canvas);
    canvas.restore();
}

This could be used e.g. in any onDraw() method of any custom view.

How to remove all MySQL tables from the command-line without DROP database permissions?

Try this.

This works even for tables with constraints (foreign key relationships). Alternatively you can just drop the database and recreate, but you may not have the necessary permissions to do that.

mysqldump -u[USERNAME] -p[PASSWORD] \
  --add-drop-table --no-data [DATABASE] | \
  grep -e '^DROP \| FOREIGN_KEY_CHECKS' | \
  mysql -u[USERNAME] -p[PASSWORD] [DATABASE]

In order to overcome foreign key check effects, add show table at the end of the generated script and run many times until the show table command results in an empty set.

anaconda update all possible packages?

Imagine the dependency graph of packages, when the number of packages grows large, the chance of encountering a conflict when upgrading/adding packages is much higher. To avoid this, simply create a new environment in Anaconda.

Be frugal, install only what you need. For me, I installed the following packages in my new environment:

  • pandas
  • scikit-learn
  • matplotlib
  • notebook
  • keras

And I have 84 packages in total.

RecyclerView onClick

Here is a strategy that gives a result similar to the ListView implementation in that you can define the listener in the Activity or Fragment level instead of the Adapter or ViewHolder level. It also defines some abstract classes that take care of a lot of the boilerplate work of adapters and holders.

Abstract Classes

First, define an abstract Holder that extends RecyclerView.ViewHolder and defines a generic data type, T, used to bind data to the views. The bindViews method will be implemented by a subclass to map data to the views.

public abstract class Holder<T> extends RecyclerView.ViewHolder {
    T data;

    public Holder(View itemView) {
        super(itemView);
    }

    public void bindData(T data){
        this.data = data;
        bindViews(data);
    }

    abstract protected void bindViews(T data);
}

Also, create an abstract Adapter that extends RecyclerView.Adapter<Holder<T>>. This defines 2 of the 3 interface methods, and a subclass will need to implement the last, onViewHolderCreated method.

public abstract class Adapter<T> extends RecyclerView.Adapter<Holder<T>> {
    List<T> list = new ArrayList<>();

    @Override
    public void onBindViewHolder(Holder<T> holder, int position) {
        holder.bindData(list.get(position));
    }

    @Override
    public int getItemCount() {
        return list.size();
    }

    public T getItem(int adapterPosition){
        return list.get(adapterPosition);
    }
}

Concrete Classes

Now create a new concrete class that extends Holder. This method only has to define the Views and handle the binding. Here I'm using the ButterKnife library, but feel free to use itemView.findViewById(...) methods instead.

public class PersonHolder extends Holder<Person>{
    @Bind(R.id.firstname) TextView firstname;
    @Bind(R.id.lastname) TextView lastname;

    public PersonHolder(View view){
        super(view);
        ButterKnife.bind(this, view);
    }

    @Override
    protected void bindViews(Person person) {
        firstname.setText(person.firstname);
        lastname.setText(person.lastname);
    }
}

Finally, in your Activity or Fragment class that holds the RecyclerView you would have this code:

// Create adapter, this happens in parent Activity or Fragment of RecyclerView
adapter = new Adapter<Person>(){
    @Override
    public PersonHolder onCreateViewHolder(ViewGroup parent, int viewType) {
        View v = LayoutInflater.from(parent.getContext())
                    .inflate(R.layout.layout_person_view, parent, false);

        PersonHolder holder = new PersonHolder(v);
        v.setOnClickListener(new OnClickListener(){
            @Override
            public void onClick(View v) {
                int itemPos = holder.getAdapterPosition();
                Person person = getItem(itemPos);

                // do something with person
                EventBus.getDefault().postSticky(new PersonClickedEvent(itemPos, person));
            }
        });

        return holder;
    }
};

What is the proper way to comment functions in Python?

Read about using docstrings in your Python code.

As per the Python docstring conventions:

The docstring for a function or method should summarize its behavior and document its arguments, return value(s), side effects, exceptions raised, and restrictions on when it can be called (all if applicable). Optional arguments should be indicated. It should be documented whether keyword arguments are part of the interface.

There will be no golden rule, but rather provide comments that mean something to the other developers on your team (if you have one) or even to yourself when you come back to it six months down the road.

Amazon S3 upload file and get URL

@hussachai and @Jeffrey Kemp answers are pretty good. But they have something in common is the url returned is of virtual-host-style, not in path style. For more info regarding to the s3 url style, can refer to AWS S3 URL Styles. In case of some people want to have path style s3 url generated. Here's the step. Basically everything will be the same as @hussachai and @Jeffrey Kemp answers, only with one line setting change as below:

AmazonS3Client s3Client = (AmazonS3Client) AmazonS3ClientBuilder.standard()
                    .withRegion("us-west-2")
                    .withCredentials(DefaultAWSCredentialsProviderChain.getInstance())
                    .withPathStyleAccessEnabled(true)
                    .build();

// Upload a file as a new object with ContentType and title specified.
PutObjectRequest request = new PutObjectRequest(bucketName, stringObjKeyName, fileToUpload);
s3Client.putObject(request);
URL s3Url = s3Client.getUrl(bucketName, stringObjKeyName);
logger.info("S3 url is " + s3Url.toExternalForm());

This will generate url like: https://s3.us-west-2.amazonaws.com/mybucket/myfilename

Eclipse internal error while initializing Java tooling

In my case, I restarted my eclipse IDE without deleting/editing my workspace or .metadata folder. Error "An internal error occurred during: "Initializing Java Tooling". java.lang.NullPointerException" is gone and Eclipse just working good.

How to detect the device orientation using CSS media queries?

@media all and (orientation:portrait) {
/* Style adjustments for portrait mode goes here */
}

@media all and (orientation:landscape) {
  /* Style adjustments for landscape mode goes here */
}

but it still looks like you have to experiment

How to find foreign key dependencies in SQL Server?

After long search I found a working solution. My database does not use the sys.foreign_key_columns and the information_schema.key_column_usage only contain primary keys.

I use SQL Server 2015

SOLUTION 1 (rarely used)

If other solutions does not work, this will work fine:

        WITH CTE AS
        (
            SELECT 
                TAB.schema_id,
                TAB.name,
                COL.name AS COLNAME,
                COl.is_identity
            FROM 
                sys.tables TAB INNER JOIN sys.columns COL 
                    ON TAB.object_id = COL.object_id
        )
        SELECT 
            DB_NAME() AS [Database], 
            SCHEMA_NAME(Child.schema_id) AS 'Schema',
            Child.name AS 'ChildTable',
            Child.COLNAME AS 'ChildColumn',
            Parent.name AS 'ParentTable',
            Parent.COLNAME AS 'ParentColumn'
        FROM 
            cte Child INNER JOIN CTE Parent
                ON 
                    Child.COLNAME=Parent.COLNAME AND 
                    Child.name<>Parent.name AND 
                    Child.is_identity+1=Parent.is_identity

SOLUTION 2 (commonly used)

In most of the cases this will work just fine:

        SELECT
            DB_NAME() AS [Database], 
            SCHEMA_NAME(fk.schema_id) AS 'Schema',
            fk.name 'Name',
            tp.name 'ParentTable',
            cp.name 'ParentColumn',
            cp.column_id,
            tr.name 'ChildTable',
            cr.name 'ChildColumn',
            cr.column_id
        FROM
            sys.foreign_keys fk
        INNER JOIN
            sys.tables tp ON fk.parent_object_id = tp.object_id
        INNER JOIN
            sys.tables tr ON fk.referenced_object_id = tr.object_id
        INNER JOIN
            sys.foreign_key_columns fkc ON fkc.constraint_object_id = fk.object_id
        INNER JOIN
            sys.columns cp ON fkc.parent_column_id = cp.column_id AND fkc.parent_object_id = cp.object_id
        INNER JOIN
            sys.columns cr ON fkc.referenced_column_id = cr.column_id AND fkc.referenced_object_id = cr.object_id
        WHERE 
            -- CONCAT(SCHEMA_NAME(fk.schema_id), '.', tp.name, '.', cp.name) LIKE '%my_table_name%' OR
            -- CONCAT(SCHEMA_NAME(fk.schema_id), '.', tr.name, '.', cr.name) LIKE '%my_table_name%' 
        ORDER BY
            tp.name, cp.column_id

How to tell bash that the line continues on the next line

The character is a backslash \

From the bash manual:

The backslash character ‘\’ may be used to remove any special meaning for the next character read and for line continuation.

ssh_exchange_identification: Connection closed by remote host under Git bash

I experienced this today and I just do a:

12345@123456 MINGW64 ~/development/workspace/test (develop)
$ git status
Refresh index: 100% (1204/1204), done.
On branch develop
Your branch is up to date with 'origin/develop'.

nothing to commit, working tree clean

12345@123456 MINGW64 ~/development/workspace/test (develop)
$ git fetch

Then all worked again.

Amazon AWS Filezilla transfer permission denied

In my case the /var/www/html in not a directory but a symbolic link to the /var/app/current, so you should change the real directoy ie /var/app/current:

sudo chown -R ec2-user /var/app/current
sudo chmod -R 755 /var/app/current

I hope this save some of your times :)

Installation of VB6 on Windows 7 / 8 / 10

VB6 Installs just fine on Windows 7 (and Windows 8 / Windows 10) with a few caveats.

Here is how to install it:

  • Before proceeding with the installation process below, create a zero-byte file in C:\Windows called MSJAVA.DLL. The setup process will look for this file, and if it doesn't find it, will force an installation of old, old Java, and require a reboot. By creating the zero-byte file, the installation of moldy Java is bypassed, and no reboot will be required.
  • Turn off UAC.
  • Insert Visual Studio 6 CD.
  • Exit from the Autorun setup.
  • Browse to the root folder of the VS6 CD.
  • Right-click SETUP.EXE, select Run As Administrator.
  • On this and other Program Compatibility Assistant warnings, click Run Program.
  • Click Next.
  • Click "I accept agreement", then Next.
  • Enter name and company information, click Next.
  • Select Custom Setup, click Next.
  • Click Continue, then Ok.
  • Setup will "think to itself" for about 2 minutes. Processing can be verified by starting Task Manager, and checking the CPU usage of ACMSETUP.EXE.
  • On the options list, select the following:
    • Microsoft Visual Basic 6.0
    • ActiveX
    • Data Access
    • Graphics
    • All other options should be unchecked.
  • Click Continue, setup will continue.
  • Finally, a successful completion dialog will appear, at which click Ok. At this point, Visual Basic 6 is installed.
  • If you do not have the MSDN CD, clear the checkbox on the next dialog, and click next. You'll be warned of the lack of MSDN, but just click Yes to accept.
  • Click Next to skip the installation of Installshield. This is a really old version you don't want anyway.
  • Click Next again to skip the installation of BackOffice, VSS, and SNA Server. Not needed!
  • On the next dialog, clear the checkbox for "Register Now", and click Finish.
  • The wizard will exit, and you're done. You can find VB6 under Start, All Programs, Microsoft Visual Studio 6. Enjoy!
  • Turn On UAC again

  • You might notice after successfully installing VB6 on Windows 7 that working in the IDE is a bit, well, sluggish. For example, resizing objects on a form is a real pain.
  • After installing VB6, you'll want to change the compatibility settings for the IDE executable.
  • Using Windows Explorer, browse the location where you installed VB6. By default, the path is C:\Program Files\Microsoft Visual Studio\VB98\
  • Right click the VB6.exe program file, and select properties from the context menu.
  • Click on the Compatibility tab.
  • Place a check in each of these checkboxes:
  • Run this program in compatibility mode for Windows XP (Service Pack 3)
    • Disable Visual Themes
    • Disable Desktop Composition
    • Disable display scaling on high DPI settings
    • If you have UAC turned on, it is probably advisable to check the 'Run this program as an Administrator' box

After changing these settings, fire up the IDE, and things should be back to normal, and the IDE is no longer sluggish.

Edit: Updated dead link to point to a different page with the same instructions

Edit: Updated the answer with the actual instructions in the post as the link kept dying

Percentage width in a RelativeLayout

Interestingly enough, building on the answer from @olefevre, one can not only do 50/50 layouts with "invisible struts", but all sorts of layouts involving powers of two.

For example, here is a layout that cuts the width into four equal parts (actually three, with weights of 1, 1, 2):

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

    <View
        android:id="@+id/strut"
        android:layout_width="1dp"
        android:layout_height="match_parent"
        android:layout_centerHorizontal="true"
        android:background="#000000" />

    <RelativeLayout
        android:layout_width="match_parent"
        android:layout_height="wrap_content"
        android:layout_toLeftOf="@+id/strut" >

        <View
            android:id="@+id/left_strut"
            android:layout_width="1dp"
            android:layout_height="match_parent"
            android:layout_toLeftOf="@+id/strut"
            android:layout_centerHorizontal="true"
            android:background="#000000" />

        <Button
            android:layout_width="0dp"
            android:layout_height="wrap_content"
            android:layout_alignParentLeft="true"
            android:layout_alignRight="@+id/left_strut"
            android:text="Far Left" />

        <Button
            android:layout_width="0dp"
            android:layout_height="wrap_content"
            android:layout_alignParentRight="true"
            android:layout_toRightOf="@+id/left_strut"
            android:text="Near Left" />
    </RelativeLayout>

        <Button
            android:layout_width="0dp"
            android:layout_height="wrap_content"
            android:layout_alignLeft="@id/strut"
            android:layout_alignParentRight="true"
            android:text="Right" />

</RelativeLayout>

Maven compile with multiple src directories

Used the build-helper-maven-plugin from the post - and update src/main/generated. And mvn clean compile works on my ../common/src/main/java, or on ../common, so kept the latter. Then yes, confirming that IntelliJ IDEA (ver 10.5.2) level of the compilation failed as David Phillips mentioned. The issue was that IDEA did not add another source root to the project. Adding it manually solved the issue. It's not nice as editing anything in the project should come from maven and not from direct editing of IDEA's project options. Yet I will be able to live with it until they support build-helper-maven-plugin directly such that it will auto add the sources.

Then needed another workaround to make this work though. Since each time IDEA re-imported maven settings after a pom change me newly added source was kept on module, yet it lost it's Source Folders selections and was useless. So for IDEA - need to set these once:

  • Select - Project Settings / Maven / Importing / keep source and test folders on reimport.
  • Add - Project Structure / Project Settings / Modules / {Module} / Sources / Add Content Root.

Now keeping those folders on import is not the best practice in the world either, ..., but giving it a try.

Angular IE Caching issue for $http

The correct, server-side, solution: Better Way to Prevent IE Cache in AngularJS?

[OutputCache(NoStore = true, Duration = 0, VaryByParam = "None")]
public ActionResult Get()
{
    // return your response
}

How to export private key from a keystore of self-signed certificate

http://anandsekar.github.io/exporting-the-private-key-from-a-jks-keystore/

public class ExportPrivateKey {
        private File keystoreFile;
        private String keyStoreType;
        private char[] password;
        private String alias;
        private File exportedFile;

        public static KeyPair getPrivateKey(KeyStore keystore, String alias, char[] password) {
                try {
                        Key key=keystore.getKey(alias,password);
                        if(key instanceof PrivateKey) {
                                Certificate cert=keystore.getCertificate(alias);
                                PublicKey publicKey=cert.getPublicKey();
                                return new KeyPair(publicKey,(PrivateKey)key);
                        }
                } catch (UnrecoverableKeyException e) {
        } catch (NoSuchAlgorithmException e) {
        } catch (KeyStoreException e) {
        }
        return null;
        }

        public void export() throws Exception{
                KeyStore keystore=KeyStore.getInstance(keyStoreType);
                BASE64Encoder encoder=new BASE64Encoder();
                keystore.load(new FileInputStream(keystoreFile),password);
                KeyPair keyPair=getPrivateKey(keystore,alias,password);
                PrivateKey privateKey=keyPair.getPrivate();
                String encoded=encoder.encode(privateKey.getEncoded());
                FileWriter fw=new FileWriter(exportedFile);
                fw.write(“—–BEGIN PRIVATE KEY—–\n“);
                fw.write(encoded);
                fw.write(“\n“);
                fw.write(“—–END PRIVATE KEY—–”);
                fw.close();
        }


        public static void main(String args[]) throws Exception{
                ExportPrivateKey export=new ExportPrivateKey();
                export.keystoreFile=new File(args[0]);
                export.keyStoreType=args[1];
                export.password=args[2].toCharArray();
                export.alias=args[3];
                export.exportedFile=new File(args[4]);
                export.export();
        }
}

Java String to SHA1

Base 64 Representation of SHA1 Hash:

String hashedVal = Base64.getEncoder().encodeToString(DigestUtils.sha1(stringValue.getBytes(Charset.forName("UTF-8"))));

CSS position absolute full width problem

I have similar situation. In my case, it doesn't have a parent with position:relative. Just paste my solution here for those that might need.

position: fixed;
left: 0;
right: 0;

Attach a body onload event with JS

This takes advantage of DOMContentLoaded - which fires before onload - but allows you to stick in all your unobtrusiveness...

window.onload - Dean Edwards - The blog post talks more about it - and here is the complete code copied from the comments of that same blog.

// Dean Edwards/Matthias Miller/John Resig

function init() {
  // quit if this function has already been called
  if (arguments.callee.done) return;

  // flag this function so we don't do the same thing twice
  arguments.callee.done = true;

  // kill the timer
  if (_timer) clearInterval(_timer);

  // do stuff
};

/* for Mozilla/Opera9 */
if (document.addEventListener) {
  document.addEventListener("DOMContentLoaded", init, false);
}

/* for Internet Explorer */
/*@cc_on @*/
/*@if (@_win32)
  document.write("<script id=__ie_onload defer src=javascript:void(0)><\/script>");
  var script = document.getElementById("__ie_onload");
  script.onreadystatechange = function() {
    if (this.readyState == "complete") {
      init(); // call the onload handler
    }
  };
/*@end @*/

/* for Safari */
if (/WebKit/i.test(navigator.userAgent)) { // sniff
  var _timer = setInterval(function() {
    if (/loaded|complete/.test(document.readyState)) {
      init(); // call the onload handler
    }
  }, 10);
}

/* for other browsers */
window.onload = init;

Limit to 2 decimal places with a simple pipe

Well now will be different after angular 5:

{{ number | currency :'GBP':'symbol':'1.2-2' }}

How to append a char to a std::string?

In addition to the others mentioned, one of the string constructors take a char and the number of repetitions for that char. So you can use that to append a single char.

std::string s = "hell";
s += std::string(1, 'o');

git reset --hard HEAD leaves untracked files behind

Remove all things except .git folder and then run git reset --hard

htaccess remove index.php from url

RewriteEngine On
RewriteCond %{THE_REQUEST} ^[A-Z]{3,9}\ /(.*)index\.php($|\ |\?)
RewriteRule ^ /%1 [R=301,L]

Error when checking Java version: could not find java.dll

Reinstall JDK and set system variable JAVA_HOME on your JDK. (e.g. C:\tools\jdk7)
And add JAVA_HOME variable to your PATH system variable

Type in command line

echo %JAVA_HOME%

and

java -version

To verify whether your installation was done successfully.


This problem generally occurs in Windows when your "Java Runtime Environment" registry entry is missing or mismatched with the installed JDK. The mismatch can be due to multiple JDKs.

Steps to resolve:

  1. Open the Run window:

    Press windows+R

  2. Open registry window:

    Type regedit and enter.

  3. Go to: \HKEY_LOCAL_MACHINE\SOFTWARE\JavaSoft\

  4. If Java Runtime Environment is not present inside JavaSoft, then create a new Key and give the name Java Runtime Environment.

  5. For Java Runtime Environment create "CurrentVersion" String Key and give appropriate version as value:

JRE regedit entry

  1. Create a new subkey of 1.8.

  2. For 1.8 create a String Key with name JavaHome with the value of JRE home:

    JRE regedit entry 2

Ref: https://mybindirectory.blogspot.com/2019/05/error-could-not-find-javadll.html

How to lookup JNDI resources on WebLogic?

I had a similar problem to this one. It got solved by deleting the java:comp/env/ prefix and using jdbc/myDataSource in the context lookup. Just as someone pointed out in the comments.

Biggest advantage to using ASP.Net MVC vs web forms

If you're working with other developers, such as PHP or JSP (and i'm guessing rails) - you're going to have a much easier time converting or collaborating on pages because you wont have all those 'nasty' ASP.NET events and controls everywhere.

How to check if mysql database exists

If you are looking for a php script see below.

$link = mysql_connect('localhost', 'mysql_user', 'mysql_password');
if (!$link) {
  die('Not connected : ' . mysql_error());
}

// make foo the current db
$db_selected = mysql_select_db('foo', $link);
if (!$db_selected) {
  die ('Cannot use foo : ' . mysql_error());
}

Undo a Git merge that hasn't been pushed yet

I was able to resolve this problem with a single command that doesn't involve looking up a commit id.

git reset --hard remotes/origin/HEAD

The accepted answer didn't work for me but this command achieved the results I was looking for.

How to create folder with PHP code?

In answer to the question in how to write to a file in PHP you can use the following as an example:

    $fp = fopen ($filename, "a"); # a = append to the file. w = write to the file (create new if doesn't exist)
    if ($fp) {
        fwrite ($fp, $text); //$text is what you are writing to the file
        fclose ($fp);
        $writeSuccess = "Yes";
        #echo ("File written");
    }
    else {
    $writeSuccess = "No";
    #echo ("File was not written");
    }

Difference between Visual Basic 6.0 and VBA

VB (Visual Basic only up to 6.0) is a superset of VBA (Visual Basic for Applications). I know that others have sort of eluded to this but my understanding is that the semantics (i.e. the vocabulary) of VBA is included in VB6 (except for objects specific to Office products), therefore, VBA is a subset of VB6. The syntax (i.e. the order in which the words are written) is exactly the same in VBA as it would be in VB6, but the difference is the objects available to VBA or VB6 are different because they have different purposes. Specifically VBA's purpose is to programatically automate tasks that can be done in MS Office, whereas VB6's purpose is to create standard EXE, ActiveX Controls, ActiveX DLLs and ActiveX EXEs which can either work stand alone or in other programs such as MS Office or Windows.

Is it possible to use jQuery .on and hover?

You can you use .on() with hover by doing what the Additional Notes section says:

Although strongly discouraged for new code, you may see the pseudo-event-name "hover" used as a shorthand for the string "mouseenter mouseleave". It attaches a single event handler for those two events, and the handler must examine event.type to determine whether the event is mouseenter or mouseleave. Do not confuse the "hover" pseudo-event-name with the .hover() method, which accepts one or two functions.

That would be to do the following:

$("#foo").on("hover", function(e) {

    if (e.type === "mouseenter") { console.log("enter"); }
    else if (e.type === "mouseleave") { console.log("leave"); }

});

EDIT (note for jQuery 1.8+ users):

Deprecated in jQuery 1.8, removed in 1.9: The name "hover" used as a shorthand for the string "mouseenter mouseleave". It attaches a single event handler for those two events, and the handler must examine event.type to determine whether the event is mouseenter or mouseleave. Do not confuse the "hover" pseudo-event-name with the .hover() method, which accepts one or two functions.

CSS 100% height with padding/margin

This is one of the outright idiocies of CSS - I have yet to understand the reasoning (if someone knows, pls. explain).

100% means 100% of the container height - to which any margins, borders and padding are added. So it is effectively impossible to get a container which fills it's parent and which has a margin, border, or padding.

Note also, setting height is notoriously inconsistent between browsers, too.


Another thing I've learned since I posted this is that the percentage is relative the container's length, that is, it's width, making a percentage even more worthless for height.

Nowadays, the vh and vw viewport units are more useful, but still not especially useful for anything other than the top-level containers.

How do I add a newline to a TextView in Android?

System.getProperty("line.separator"); this work for me.

Merge two objects with ES6

You can use Object.assign() to merge them into a new object:

_x000D_
_x000D_
const response = {_x000D_
  lat: -51.3303,_x000D_
  lng: 0.39440_x000D_
}_x000D_
_x000D_
const item = {_x000D_
  id: 'qwenhee-9763ae-lenfya',_x000D_
  address: '14-22 Elder St, London, E1 6BT, UK'_x000D_
}_x000D_
_x000D_
const newItem = Object.assign({}, item, { location: response });_x000D_
_x000D_
console.log(newItem );
_x000D_
_x000D_
_x000D_

You can also use object spread, which is a Stage 4 proposal for ECMAScript:

_x000D_
_x000D_
const response = {_x000D_
  lat: -51.3303,_x000D_
  lng: 0.39440_x000D_
}_x000D_
_x000D_
const item = {_x000D_
  id: 'qwenhee-9763ae-lenfya',_x000D_
  address: '14-22 Elder St, London, E1 6BT, UK'_x000D_
}_x000D_
_x000D_
const newItem = { ...item, location: response }; // or { ...response } if you want to clone response as well_x000D_
_x000D_
console.log(newItem );
_x000D_
_x000D_
_x000D_

Python 2: AttributeError: 'list' object has no attribute 'strip'

You split the string entry of the list. l[0].strip()

Is it possible to view RabbitMQ message contents directly from the command line?

You should enable the management plugin.

rabbitmq-plugins enable rabbitmq_management

See here:

http://www.rabbitmq.com/plugins.html

And here for the specifics of management.

http://www.rabbitmq.com/management.html

Finally once set up you will need to follow the instructions below to install and use the rabbitmqadmin tool. Which can be used to fully interact with the system. http://www.rabbitmq.com/management-cli.html

For example:

rabbitmqadmin get queue=<QueueName> requeue=false

will give you the first message off the queue.

What version of MongoDB is installed on Ubuntu

To be complete, a short introduction for "shell noobs":

First of all, start your shell - you can find it inside the common desktop environments under the name "Terminal" or "Shell" somewhere in the desktops application menu.

You can also try using the key combo CTRL+F2, followed by one of those commands (depending on the desktop envrionment you're using) and the ENTER key:

xfce4-terminal
gnome-console
terminal
rxvt
konsole

If all of the above fail, try using xterm - it'll work in most cases.

Hint for the following commands: Execute the commands without the $ - it's just a marker identifying that you're on the shell.

After that just fire up mongod with the --version flag:

$ mongod --version

It shows you then something like

$ mongod --version
db version v2.4.6
Wed Oct 16 16:17:00.241 git version: nogitversion

To update it just execute

$ sudo apt-get update

and then

$ sudo apt-get install mongodb

Is it bad to have my virtualenv directory inside my git repository?

I think one of the main problems which occur is that the virtualenv might not be usable by other people. Reason is that it always uses absolute paths. So if you virtualenv was for example in /home/lyle/myenv/ it will assume the same for all other people using this repository (it must be exactly the same absolute path). You can't presume people using the same directory structure as you.

Better practice is that everybody is setting up their own environment (be it with or without virtualenv) and installing libraries there. That also makes you code more usable over different platforms (Linux/Windows/Mac), also because virtualenv is installed different in each of them.

Specifing width of a flexbox flex item: width or basis?

The bottom statement is equivalent to:

.half {
   flex-grow: 0;
   flex-shrink: 0;
   flex-basis: 50%;
}

Which, in this case, would be equivalent as the box is not allowed to flex and therefore retains the initial width set by flex-basis.

Flex-basis defines the default size of an element before the remaining space is distributed so if the element were allowed to flex (grow/shrink) it may not be 50% of the width of the page.

I've found that I regularly return to https://css-tricks.com/snippets/css/a-guide-to-flexbox/ for help regarding flexbox :)

convert iso date to milliseconds in javascript

Yes, you can do this in a single line

let ms = Date.parse('2019-05-15 07:11:10.673Z');
console.log(ms);//1557904270673

Reading the selected value from asp:RadioButtonList using jQuery

For my scenario, my JS was in a separate file, so using a ClientID response output wasn't conducive. Surprisingly, the solution was as simple as adding a CssClass to the RadioButtonList, which I found out on DevCurry

Just incase that solution disappears, add a class to your radio button list

<asp:RadioButtonList id="rbl" runat="server" class="tbl">...

As the article points out, when the radio button list is rendered, the class "tbl" is appended to the surrounding table

<table id="rbl" class="tbl" border="0">
<tr>...

Now because of the CSS class that has been appended, you can just refer to input:radio items within your table, based on the css class selector

$(function () {
            var $radBtn = $("table.tbl input:radio");
            $radBtn.click(function () {
                var $radChecked = $(':radio:checked');
                alert($radChecked.val());
            });
        });

Again, this avoids using the "ClientID" mentioned above which I found messy for my scenario. Hope this helps!

CSS - Make divs align horizontally

This seems close to what you want:

_x000D_
_x000D_
#foo {_x000D_
  background: red;_x000D_
  max-height: 100px;_x000D_
  overflow-y: hidden;_x000D_
}_x000D_
_x000D_
.bar {_x000D_
  background: blue;_x000D_
  width: 100px;_x000D_
  height: 100px;_x000D_
  float: left;_x000D_
  margin: 1em;_x000D_
}
_x000D_
<div id="foo">_x000D_
  <div class="bar"></div>_x000D_
  <div class="bar"></div>_x000D_
  <div class="bar"></div>_x000D_
  <div class="bar"></div>_x000D_
  <div class="bar"></div>_x000D_
  <div class="bar"></div>_x000D_
</div>
_x000D_
_x000D_
_x000D_

HTTP Error 404 when running Tomcat from Eclipse

I had this or a similar problem after installing Tomcat.

The other answers didn't quite work, but got me on the right path. I answered this at https://stackoverflow.com/a/20762179/3128838 after discovering a YouTube video showing the exact problem I was having.

How to get current domain name in ASP.NET

You can try the following code :

 Request.Url.Host +
    (Request.Url.IsDefaultPort ? "" : ":" + Request.Url.Port)

How To Raise Property Changed events on a Dependency Property?

I question the logic of raising a PropertyChanged event on the second property when it's the first property that's changing. If the second properties value changes then the PropertyChanged event could be raised there.

At any rate, the answer to your question is you should implement INotifyPropertyChange. This interface contains the PropertyChanged event. Implementing INotifyPropertyChanged lets other code know that the class has the PropertyChanged event, so that code can hook up a handler. After implementing INotifyPropertyChange, the code that goes in the if statement of your OnPropertyChanged is:

if (PropertyChanged != null)
    PropertyChanged(new PropertyChangedEventArgs("MySecondProperty"));

What is event bubbling and capturing?

I have found this tutorial at javascript.info to be very clear in explaining this topic. And its 3-points summary at the end is really talking to the crucial points. I quote it here:

  1. Events first are captured down to deepest target, then bubble up. In IE<9 they only bubble.
  2. All handlers work on bubbling stage excepts addEventListener with last argument true, which is the only way to catch the event on capturing stage.
  3. Bubbling/capturing can be stopped by event.cancelBubble=true (IE) or event.stopPropagation() for other browsers.

Easy way to make a confirmation dialog in Angular?

I'm pretty late to the party, but here is another implementation using : https://stackblitz.com/edit/angular-confirmation-dialog

confirmation-dialog.service.ts

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

import { NgbModal } from '@ng-bootstrap/ng-bootstrap';

import { ConfirmationDialogComponent } from './confirmation-dialog.component';

@Injectable()
export class ConfirmationDialogService {

  constructor(private modalService: NgbModal) { }

  public confirm(
    title: string,
    message: string,
    btnOkText: string = 'OK',
    btnCancelText: string = 'Cancel',
    dialogSize: 'sm'|'lg' = 'sm'): Promise<boolean> {
    const modalRef = this.modalService.open(ConfirmationDialogComponent, { size: dialogSize });
    modalRef.componentInstance.title = title;
    modalRef.componentInstance.message = message;
    modalRef.componentInstance.btnOkText = btnOkText;
    modalRef.componentInstance.btnCancelText = btnCancelText;

    return modalRef.result;
  }

}

confirmation-dialog.component.ts

import { Component, Input, OnInit } from '@angular/core';
import { NgbActiveModal } from '@ng-bootstrap/ng-bootstrap';

@Component({
  selector: 'app-confirmation-dialog',
  templateUrl: './confirmation-dialog.component.html',
  styleUrls: ['./confirmation-dialog.component.scss'],
})
export class ConfirmationDialogComponent implements OnInit {

  @Input() title: string;
  @Input() message: string;
  @Input() btnOkText: string;
  @Input() btnCancelText: string;

  constructor(private activeModal: NgbActiveModal) { }

  ngOnInit() {
  }

  public decline() {
    this.activeModal.close(false);
  }

  public accept() {
    this.activeModal.close(true);
  }

  public dismiss() {
    this.activeModal.dismiss();
  }

}

confirmation-dialog.component.html

<div class="modal-header">
  <h4 class="modal-title">{{ title }}</h4>
    <button type="button" class="close" aria-label="Close" (click)="dismiss()">
      <span aria-hidden="true">&times;</span>
    </button>
  </div>
  <div class="modal-body">
    {{ message }}
  </div>
  <div class="modal-footer">
    <button type="button" class="btn btn-danger" (click)="decline()">{{ btnCancelText }}</button>
    <button type="button" class="btn btn-primary" (click)="accept()">{{ btnOkText }}</button>
  </div>

Use the dialog like this:

public openConfirmationDialog() {
    this.confirmationDialogService.confirm('Please confirm..', 'Do you really want to ... ?')
    .then((confirmed) => console.log('User confirmed:', confirmed))
    .catch(() => console.log('User dismissed the dialog (e.g., by using ESC, clicking the cross icon, or clicking outside the dialog)'));
  }

How to Compare two strings using a if in a stored procedure in sql server 2008?

You can also try this for match string.

DECLARE @temp1 VARCHAR(1000)
    SET @temp1 = '<li>Error in connecting server.</li>'
DECLARE @temp2 VARCHAR(1000)
    SET @temp2 = '<li>Error in connecting server. connection timeout.</li>'

IF @temp1 like '%Error in connecting server.%' OR @temp1 like '%Error in connecting server. connection timeout.%'
  SELECT 'yes'
ELSE
  SELECT 'no'

Difference between getContext() , getApplicationContext() , getBaseContext() and "this"

The question "what the Context is" is one of the most difficult questions in the Android universe.

Context defines methods that access system resources, retrieve application's static assets, check permissions, perform UI manipulations and many more. In essence, Context is an example of God Object anti-pattern in production.

When it comes to which kind of Context should we use, it becomes very complicated because except for being God Object, the hierarchy tree of Context subclasses violates Liskov Substitution Principle brutally.

This blog post (now from Wayback Machine) attempts to summarize Context classes applicability in different situations.

Let me copy the main table from that post for completeness:

+----------------------------+-------------+----------+---------+-----------------+-------------------+
|                            | Application | Activity | Service | ContentProvider | BroadcastReceiver |
+----------------------------+-------------+----------+---------+-----------------+-------------------+
| Show a Dialog              | NO          | YES      | NO      | NO              | NO                |
| Start an Activity          | NO¹         | YES      | NO¹     | NO¹             | NO¹               |
| Layout Inflation           | NO²         | YES      | NO²     | NO²             | NO²               |
| Start a Service            | YES         | YES      | YES     | YES             | YES               |
| Bind to a Service          | YES         | YES      | YES     | YES             | NO                |
| Send a Broadcast           | YES         | YES      | YES     | YES             | YES               |
| Register BroadcastReceiver | YES         | YES      | YES     | YES             | NO³               |
| Load Resource Values       | YES         | YES      | YES     | YES             | YES               |
+----------------------------+-------------+----------+---------+-----------------+-------------------+
  1. An application CAN start an Activity from here, but it requires that a new task be created. This may fit specific use cases, but can create non-standard back stack behaviors in your application and is generally not recommended or considered good practice.
  2. This is legal, but inflation will be done with the default theme for the system on which you are running, not what’s defined in your application.
  3. Allowed if the receiver is null, which is used for obtaining the current value of a sticky broadcast, on Android 4.2 and above.

screenshot

Change HTML email body font type and size in VBA

FYI I did a little research as well and if the name of the font-family you want to apply contains spaces (as an example I take Gill Alt One MT Light), you should write it this way :

strbody= "<BODY style=" & Chr(34) & "font-family:Gill Alt One MT Light" & Chr(34) & ">" & YOUR_TEXT & "</BODY>"

How can I send the "&" (ampersand) character via AJAX?

You can use encodeURIComponent().

It will escape all the characters that cannot occur verbatim in URLs:

var wysiwyg_clean = encodeURIComponent(wysiwyg);

In this example, the ampersand character & will be replaced by the escape sequence %26, which is valid in URLs.

No 'Access-Control-Allow-Origin' header is present on the requested resource. Origin '...' is therefore not allowed access

Add this to you PHP file or main controller

header("Access-Control-Allow-Origin: http://localhost:9000");

Fail during installation of Pillow (Python module) in Linux

The alternative, if you don't want to install libjpeg:

CFLAGS="--disable-jpeg" pip install pillow

From https://pillow.readthedocs.io/en/3.0.0/installation.html#external-libraries

Windows 7 SDK installation failure

One of the things to also keep in mind is that when you have Visual Studio 2010 SP1 installed some C++ compilers and libraries may have been removed. There's been an update made available by Microsoft to make sure those are brought back to your system.

Install this update to restore the Visual C++ compilers and libraries that may have been removed when Visual Studio 2010 Service Pack 1 (SP1) was installed. The compilers and libraries are part of the Microsoft Windows Software Development Kit for Windows 7 and the .NET Framework 4 (later referred to as the Windows SDK 7.1).

Also, when you read the VS2010 SP1 README you'll also notice that some notes have been made in regards to the Windows 7 SDK (See section 2.2.1) installation. It may be that one of these conditions may apply to you and therefore may need to uncheck the C++ compiler-checkbox as the SDK installer will attempt to install an older version of compilers ÓR you may need to uninstall VS2010 SP1 and re-run the SDK 7.1 installation, repair or modification.

Condition 1: If the Visual C++ Compilers checkbox is selected when the Windows SDK 7.1 is installed, repaired, or modified after Visual Studio 2010 SP1 has been installed, the error may be encountered and some selected components may not be installed.

Workaround: Clear the Visual C++ Compilers checkbox before you run the Windows SDK 7.1 installation, repair, or modification.

Condition 2: If the Visual C++ Compilers checkbox is selected when the Windows SDK 7.1 is installed, repaired, or modified after Visual Studio 2010 has been installed but Visual Studio 2010 SP1 has not been uninstalled, the error may be encountered.

Workaround: Uninstall Visual Studio 2010 SP1 and then rerun the Windows SDK 7.1 installation, repair, or modification.

However, even then I found that I still needed to uninstall any existing Visual C++ 2010 redistributables, as has been suggested by mgrandi.

Is there an R function for finding the index of an element in a vector?

The function match works on vectors:

x <- sample(1:10)
x
# [1]  4  5  9  3  8  1  6 10  7  2
match(c(4,8),x)
# [1] 1 5

match only returns the first encounter of a match, as you requested. It returns the position in the second argument of the values in the first argument.

For multiple matching, %in% is the way to go:

x <- sample(1:4,10,replace=TRUE)
x
# [1] 3 4 3 3 2 3 1 1 2 2
which(x %in% c(2,4))
# [1]  2  5  9 10

%in% returns a logical vector as long as the first argument, with a TRUE if that value can be found in the second argument and a FALSE otherwise.

How can I filter a date of a DateTimeField in Django?

As of Django 1.9, the way to do this is by using __date on a datetime object.

For example: MyObject.objects.filter(datetime_attr__date=datetime.date(2009,8,22))

matplotlib savefig() plots different from show()

I have fixed this in my matplotlib source, but it's not a pretty fix. However, if you, like me, are very particular about how the graph looks, it's worth it.

The issue seems to be in the rendering backends; they each get the correct values for linewidth, font size, etc., but that comes out slightly larger when rendered as a PDF or PNG than when rendered with show().

I added a few lines to the source for PNG generation, in the file matplotlib/backends/backend_agg.py. You could make similar changes for each backend you use, or find a way to make a more clever change in a single location ;)

Added to my matplotlib/backends/backend_agg.py file:

    # The top of the file, added lines 42 - 44
42  # @warning: CHANGED FROM SOURCE to draw thinner lines
43  PATH_SCALAR = .8
44  FONT_SCALAR = .95

    # In the draw_markers method, added lines 90 - 91
89  def draw_markers(self, *kl, **kw):
90      # @warning: CHANGED FROM SOURCE to draw thinner lines
91      kl[0].set_linewidth(kl[0].get_linewidth()*PATH_SCALAR)
92      return self._renderer.draw_markers(*kl, **kw)

    # At the bottom of the draw_path method, added lines 131 - 132:
130 else:
131     # @warning: CHANGED FROM SOURCE to draw thinner lines
132     gc.set_linewidth(gc.get_linewidth()*PATH_SCALAR)
133     self._renderer.draw_path(gc, path, transform, rgbFace)

    # At the bottom of the _get_agg_font method, added line 242 and the *FONT_SCALAR
241     font.clear()
242     # @warning: CHANGED FROM SOURCE to draw thinner lines
243     size = prop.get_size_in_points()*FONT_SCALAR
244     font.set_size(size, self.dpi)

So that suits my needs for now, but, depending on what you're doing, you may want to implement similar changes in other methods. Or find a better way to do the same without so many line changes!

Update: After posting an issue to the matplotlib project at Github, I was able to track down the source of my problem: I had changed the figure.dpi setting in the matplotlibrc file. If that value is different than the default, my savefig() images come out different, even if I set the savefig dpi to be the same as the figure dpi. So, instead of changing the source as above, I just kept the figure.dpi setting as the default 80, and was able to generate images with savefig() that looked like images from show().

Leon, had you also changed that setting?

Editing an item in a list<T>

  1. You can use the FindIndex() method to find the index of item.
  2. Create a new list item.
  3. Override indexed item with the new item.

List<Class1> list = new List<Class1>();

int index = list.FindIndex(item => item.Number == textBox6.Text);

Class1 newItem = new Class1();
newItem.Prob1 = "SomeValue";

list[index] = newItem;

Java: Identifier expected

Put your code in a method.

Try this:

public class MyClass {
    public static void main(String[] args) {
        UserInput input = new UserInput();
        input.name();
    }
}

Then "run" the class from your IDE

How can I remove duplicate rows?

I you want to preview the rows you are about to remove and keep control over which of the duplicate rows to keep. See http://developer.azurewebsites.net/2014/09/better-sql-group-by-find-duplicate-data/

with MYCTE as (
  SELECT ROW_NUMBER() OVER (
    PARTITION BY DuplicateKey1
                ,DuplicateKey2 -- optional
    ORDER BY CreatedAt -- the first row among duplicates will be kept, other rows will be removed
  ) RN
  FROM MyTable
)
DELETE FROM MYCTE
WHERE RN > 1

Re-sign IPA (iPhone)

Finally got this working!

Tested with a IPA signed with cert1 for app store submission with no devices added in the provisioning profile. Results in a new IPA signed with a enterprise account and a mobile provisioning profile for in house deployment (the mobile provisioning profile gets embedded to the IPA).

Solution:

Unzip the IPA

unzip Application.ipa

Remove old CodeSignature

rm -r "Payload/Application.app/_CodeSignature" "Payload/Application.app/CodeResources" 2> /dev/null | true

Replace embedded mobile provisioning profile

cp "MyEnterprise.mobileprovision" "Payload/Application.app/embedded.mobileprovision"

Re-sign

/usr/bin/codesign -f -s "iPhone Distribution: Certificate Name" --resource-rules "Payload/Application.app/ResourceRules.plist" "Payload/Application.app"

Re-package

zip -qr "Application.resigned.ipa" Payload

Edit: Removed the Entitlement part (see alleys comment, thanks)

Apple Cover-flow effect using jQuery or other library?

Try Jquery Interface Elements here - http://interface.eyecon.ro/docs/carousel

Here's a sample. http://interface.eyecon.ro/demos/carousel.html

I looked around for a Jquery image carousel a few months ago and didn't find a good one so I gave up. This one was the best I could find.

How to deal with certificates using Selenium?

Just an update regarding this issue.

Require Drivers:

Linux: Centos 7 64bit, Window 7 64bit

Firefox: 52.0.3

Selenium Webdriver: 3.4.0 (Windows), 3.8.1 (Linux Centos)

GeckoDriver: v0.16.0 (Windows), v0.17.0 (Linux Centos)

Code

System.setProperty("webdriver.gecko.driver", "/home/seleniumproject/geckodrivers/linux/v0.17/geckodriver");

ProfilesIni ini = new ProfilesIni();


// Change the profile name to your own. The profile name can 
// be found under .mozilla folder ~/.mozilla/firefox/profile. 
// See you profile.ini for the default profile name

FirefoxProfile profile = ini.getProfile("default"); 

DesiredCapabilities cap = new DesiredCapabilities();
cap.setAcceptInsecureCerts(true);

FirefoxBinary firefoxBinary = new FirefoxBinary();

GeckoDriverService service =new GeckoDriverService.Builder(firefoxBinary)
    .usingDriverExecutable(new 
File("/home/seleniumproject/geckodrivers/linux/v0.17/geckodriver"))
    .usingAnyFreePort()
    .usingAnyFreePort()
    .build();
try {
    service.start();
} catch (IOException e) {
    e.printStackTrace();
}

FirefoxOptions options = new FirefoxOptions().setBinary(firefoxBinary).setProfile(profile).addCapabilities(cap);

driver = new FirefoxDriver(options);
driver.get("https://www.google.com");

System.out.println("Life Title -> " + driver.getTitle());
driver.close();

MySQL my.cnf file - Found option without preceding group

it is because of letters or digit infront of [mysqld] just check the leeters or digit anything is not required before [mysqld]

it may be something like

0[mysqld] then this error will occur

How to install a specific version of a package with pip?

Use ==:

pip install django_modeltranslation==0.4.0-beta2

Deleting rows with MySQL LEFT JOIN

DELETE FROM deadline where ID IN (
    SELECT d.ID FROM `deadline` d LEFT JOIN `job` ON deadline.job_id = job.job_id WHERE `status` =  'szamlazva' OR `status` = 'szamlazhato' OR `status` = 'fizetve' OR `status` = 'szallitva' OR `status` = 'storno');

I am not sure if that kind of sub query works in MySQL, but try it. I am assuming you have an ID column in your deadline table.

A cycle was detected in the build path of project xxx - Build Path Problem

I have this problem,too.I just disable Workspace resolution,and then all was right.enter image description here

iterating through json object javascript

My problem was actually a problem of bad planning with the JSON object rather than an actual logic issue. What I ended up doing was organize the object as follows, per a suggestion from user2736012.

{
"dialog":
{
    "trunks":[
    {
        "trunk_id" : "1",
        "message": "This is just a JSON Test"
    },
    {
        "trunk_id" : "2",
        "message": "This is a test of a bit longer text. Hopefully this will at the very least create 3 lines and trigger us to go on to another box. So we can test multi-box functionality, too."
    }
    ]
}
}

At that point, I was able to do a fairly simple for loop based on the total number of objects.

var totalMessages = Object.keys(messages.dialog.trunks).length;

    for ( var i = 0; i < totalMessages; i++)
    {
        console.log("ID: " + messages.dialog.trunks[i].trunk_id + " Message " + messages.dialog.trunks[i].message);
    }

My method for getting totalMessages is not supported in all browsers, though. For my project, it actually doesn't matter, but beware of that if you choose to use something similar to this.

What is output buffering?

I know that this is an old question but I wanted to write my answer for visual learners. I couldn't find any diagrams explaining output buffering on the worldwide-web so I made a diagram myself in Windows mspaint.exe.

If output buffering is turned off, then echo will send data immediately to the Browser.

enter image description here

If output buffering is turned on, then an echo will send data to the output buffer before sending it to the Browser.

enter image description here

phpinfo

To see whether Output buffering is turned on / off please refer to phpinfo at the core section. The output_buffering directive will tell you if Output buffering is on/off.

enter image description here In this case the output_buffering value is 4096 which means that the buffer size is 4 KB. It also means that Output buffering is turned on, on the Web server.

php.ini

It's possible to turn on/off and change buffer size by changing the value of the output_buffering directive. Just find it in php.ini, change it to the setting of your choice, and restart the Web server. You can find a sample of my php.ini below.

; Output buffering is a mechanism for controlling how much output data
; (excluding headers and cookies) PHP should keep internally before pushing that
; data to the client. If your application's output exceeds this setting, PHP
; will send that data in chunks of roughly the size you specify.
; Turning on this setting and managing its maximum buffer size can yield some
; interesting side-effects depending on your application and web server.
; You may be able to send headers and cookies after you've already sent output
; through print or echo. You also may see performance benefits if your server is
; emitting less packets due to buffered output versus PHP streaming the output
; as it gets it. On production servers, 4096 bytes is a good setting for performance
; reasons.
; Note: Output buffering can also be controlled via Output Buffering Control
;   functions.
; Possible Values:
;   On = Enabled and buffer is unlimited. (Use with caution)
;   Off = Disabled
;   Integer = Enables the buffer and sets its maximum size in bytes.
; Note: This directive is hardcoded to Off for the CLI SAPI
; Default Value: Off
; Development Value: 4096
; Production Value: 4096
; http://php.net/output-buffering
output_buffering = 4096

The directive output_buffering is not the only configurable directive regarding Output buffering. You can find other configurable Output buffering directives here: http://php.net/manual/en/outcontrol.configuration.php

Example: ob_get_clean()

Below you can see how to capture an echo and manipulate it before sending it to the browser.

// Turn on output buffering  
ob_start();  

echo 'Hello World';  // save to output buffer

$output = ob_get_clean();  // Get content from the output buffer, and discard the output buffer ...
$output = strtoupper($output); // manipulate the output  

echo $output;  // send to output stream / Browser

// OUTPUT:  
HELLO WORLD

Examples: Hackingwithphp.com

More info about Output buffer with examples can be found here:

http://www.hackingwithphp.com/13/0/0/output-buffering

What's the best way to build a string of delimited items in Java?

Instead of using string concatenation, you should use StringBuilder if your code is not threaded, and StringBuffer if it is.

How to get the new value of an HTML input after a keypress has modified it?

Here is a table of the different events and the levels of browser support. You need to pick an event which is supported across at least all modern browsers.

As you will see from the table, the keypress and change event do not have uniform support whereas the keyup event does.

Also make sure you attach the event handler using a cross-browser-compatible method...

How can I force browsers to print background images in CSS?

Browsers, by default, have their option to print background-colors and images turned off. You can add some lines in CSS to bypass this. Just add:

* {
    -webkit-print-color-adjust: exact !important;   /* Chrome, Safari */
    color-adjust: exact !important;                 /*Firefox*/
}

Nested jQuery.each() - continue/break

You can break the $.each() loop at a particular iteration by making the callback function return false.

Returning non-false is the same as a continue statement in a for loop; it will skip immediately to the next iteration.

C# ASP.NET MVC Return to Previous Page

Here is just another option you couold apply for ASP NET MVC.

Normally you shoud use BaseController class for each Controller class.

So inside of it's constructor method do following.

public class BaseController : Controller
{
        public BaseController()
        {
            // get the previous url and store it with view model
            ViewBag.PreviousUrl = System.Web.HttpContext.Current.Request.UrlReferrer;
        }
}

And now in ANY view you can do like

<button class="btn btn-success mr-auto" onclick="  window.location.href = '@ViewBag.PreviousUrl'; " style="width:2.5em;"><i class="fa fa-angle-left"></i></button>

Enjoy!

What is the difference between linear regression and logistic regression?

Cannot agree more with the above comments. Above that, there are some more differences like

In Linear Regression, residuals are assumed to be normally distributed. In Logistic Regression, residuals need to be independent but not normally distributed.

Linear Regression assumes that a constant change in the value of the explanatory variable results in constant change in the response variable. This assumption does not hold if the value of the response variable represents a probability (in Logistic Regression)

GLM(Generalized linear models) does not assume a linear relationship between dependent and independent variables. However, it assumes a linear relationship between link function and independent variables in logit model.

How do I replicate a \t tab space in HTML?

&nbsp;&nbsp;&nbsp;&nbsp; would be a work around if you're only after the spacing.

Select <a> which href ends with some string

$("a[href*=ABC]").addClass('selected');

Get first date of current month in java

Works Like a charm!

public static String  getCurrentMonthFirstDate(){
    Calendar c = Calendar.getInstance();   
    c.set(Calendar.DAY_OF_MONTH, 1);
    DateFormat df = new SimpleDateFormat("MM-dd-yyyy");
    //System.out.println(df.format(c.getTime())); 
    return df.format(c.getTime());
}

//Correction :output =02-01-2018enter image description here

How to change the Spyder editor background to dark?

If you're using Spyder 3, please go to

Tools > Preferences > Syntax Coloring

and select there the dark theme you want to use.

In Spyder 4, a dark theme is used by default. But if you want to select a different theme you can go to

Tools > Preferences > Appearance > Syntax highlighting theme

Signtool error: No certificates were found that met all given criteria with a Windows Store App?

When getting this error through Visual Studio it was because there was a signing certificate setup to match the computer it was originally developed on.

You can check this by going to the project properties > signing tab and checking the certificate details.

You can uncheck "Sign the ClickOnce manifests" to disable signing.

Signing Properties

If you don't want to turn this option off you will have to install the certificate.

Javascript reduce() on Object

An object can be turned into an array with: Object.entries(), Object.keys(), Object.values(), and then be reduced as array. But you can also reduce an object without creating the intermediate array.

I've created a little helper library odict for working with objects.

npm install --save odict

It has reduce function that works very much like Array.prototype.reduce():

export const reduce = (dict, reducer, accumulator) => {
  for (const key in dict)
    accumulator = reducer(accumulator, dict[key], key, dict);
  return accumulator;
};

You could also assign it to:

Object.reduce = reduce;

as this method is very useful!

So the answer to your question would be:

const result = Object.reduce(
  {
    a: {value:1},
    b: {value:2},
    c: {value:3},
  },
  (accumulator, current) => (accumulator.value += current.value, accumulator), // reducer function must return accumulator
  {value: 0} // initial accumulator value
);

How can I escape a single quote?

Represent it as a text entity (ASCII 39):

<input type='text' id='abc' value='hel&#39;lo'>

How should I use try-with-resources with JDBC?

What about creating an additional wrapper class?

package com.naveen.research.sql;

import java.sql.Connection;
import java.sql.PreparedStatement;
import java.sql.ResultSet;
import java.sql.SQLException;

public abstract class PreparedStatementWrapper implements AutoCloseable {

    protected PreparedStatement stat;

    public PreparedStatementWrapper(Connection con, String query, Object ... params) throws SQLException {
        this.stat = con.prepareStatement(query);
        this.prepareStatement(params);
    }

    protected abstract void prepareStatement(Object ... params) throws SQLException;

    public ResultSet executeQuery() throws SQLException {
        return this.stat.executeQuery();
    }

    public int executeUpdate() throws SQLException {
        return this.stat.executeUpdate();
    }

    @Override
    public void close() {
        try {
            this.stat.close();
        } catch (SQLException e) {
            e.printStackTrace();
        }
    }
}


Then in the calling class you can implement prepareStatement method as:

try (Connection con = DriverManager.getConnection(JDBC_URL, prop);
    PreparedStatementWrapper stat = new PreparedStatementWrapper(con, query,
                new Object[] { 123L, "TEST" }) {
            @Override
            protected void prepareStatement(Object... params) throws SQLException {
                stat.setLong(1, Long.class.cast(params[0]));
                stat.setString(2, String.valueOf(params[1]));
            }
        };
        ResultSet rs = stat.executeQuery();) {
    while (rs.next())
        System.out.println(String.format("%s, %s", rs.getString(2), rs.getString(1)));
} catch (SQLException e) {
    e.printStackTrace();
}

What is a file with extension .a?

.a files are created with the ar utility, and they are libraries. To use it with gcc, collect all .a files in a lib/ folder and then link with -L lib/ and -l<name of specific library>.

Collection of all .a files into lib/ is optional. Doing so makes for better looking directories with nice separation of code and libraries, IMHO.

concatenate two strings

You can use concatenation operator and instead of declaring two variables only use one variable

String finalString =  cursor.getString(numcol) + cursor.getString(cursor.getColumnIndexOrThrow(db.KEY_DESTINATIE));

Open Source Javascript PDF viewer

Well it's not even close to the full spec, but there is a JavaScript and Canvas based PDF viewer out there.

Offline Speech Recognition In Android (JellyBean)

Google did quietly enable offline recognition in that Search update, but there is (as yet) no API or additional parameters available within the SpeechRecognizer class. {See Edit at the bottom of this post} The functionality is available with no additional coding, however the user’s device will need to be configured correctly for it to begin working and this is where the problem lies and I would imagine why a lot of developers assume they are ‘missing something’.

Also, Google have restricted certain Jelly Bean devices from using the offline recognition due to hardware constraints. Which devices this applies to is not documented, in fact, nothing is documented, so configuring the capabilities for the user has proved to be a matter of trial and error (for them). It works for some straight away – For those that it doesn't, this is the ‘guide’ I supply them with.

  1. Make sure the default Android Voice Recogniser is set to Google not Samsung/Vlingo
  2. Uninstall any offline recognition files you already have installed from the Google Voice Search Settings
  3. Go to your Android Application Settings and see if you can uninstall the updates for the Google Search and Google Voice Search applications.
  4. If you can't do the above, go to the Play Store see if you have the option there.
  5. Reboot (if you achieved 2, 3 or 4)
  6. Update Google Search and Google Voice Search from the Play Store (if you achieved 3 or 4 or if an update is available anyway).
  7. Reboot (if you achieved 6)
  8. Install English UK offline language files
  9. Reboot
  10. Use utter! with a connection
  11. Switch to aeroplane mode and give it a try
  12. Once it is working, the offline recognition of other languages, such as English US should start working too.

EDIT: Temporarily changing the device locale to English UK also seems to kickstart this to work for some.

Some users reported they still had to reboot a number of times before it would begin working, but they all get there eventually, often inexplicably to what was the trigger, the key to which are inside the Google Search APK, so not in the public domain or part of AOSP.

From what I can establish, Google tests the availability of a connection prior to deciding whether to use offline or online recognition. If a connection is available initially but is lost prior to the response, Google will supply a connection error, it won’t fall-back to offline. As a side note, if a request for the network synthesised voice has been made, there is no error supplied it if fails – You get silence.

The Google Search update enabled no additional features in Google Now and in fact if you try to use it with no internet connection, it will error. I mention this as I wondered if the ability would be withdrawn as quietly as it appeared and therefore shouldn't be relied upon in production.

If you intend to start using the SpeechRecognizer class, be warned, there is a pretty major bug associated with it, which require your own implementation to handle.

Not being able to specifically request offline = true, makes controlling this feature impossible without manipulating the data connection. Rubbish. You’ll get hundreds of user emails asking you why you haven’t enabled something so simple!

EDIT: Since API level 23 a new parameter has been added EXTRA_PREFER_OFFLINE which the Google recognition service does appear to adhere to.

Hope the above helps.

Easiest way to make lua script wait/pause/sleep/block for a few seconds?

I believe for windows you may use: os.execute("ping 1.1.1.1 /n 1 /w <time in milliseconds> >nul as a simple timer. (remove the "<>" when inserting the time in milliseconds) (there is a space between the rest of the code and >nul)

regular expression for Indian mobile numbers

var PHONE_REGEXP = /^[789]\d{9}$/;

this works for ng-pattern in angularjs or in javascript or any js framework

Remove or adapt border of frame of legend using matplotlib

One more related question, since it took me forever to find the answer:

How to make the legend background blank (i.e. transparent, not white):

legend = plt.legend()
legend.get_frame().set_facecolor('none')

Warning, you want 'none' (the string). None means the default color instead.

Show/Hide the console window of a C# console application

Here’s how:

using System.Runtime.InteropServices;

[DllImport("kernel32.dll")]
static extern IntPtr GetConsoleWindow();

[DllImport("user32.dll")]
static extern bool ShowWindow(IntPtr hWnd, int nCmdShow);

const int SW_HIDE = 0;
const int SW_SHOW = 5;

var handle = GetConsoleWindow();

// Hide
ShowWindow(handle, SW_HIDE);

// Show
ShowWindow(handle, SW_SHOW);

Allow 2 decimal places in <input type="number">

If case anyone is looking for a regex that allows only numbers with an optional 2 decimal places

^\d*(\.\d{0,2})?$

For an example, I have found solution below to be fairly reliable

HTML:

<input name="my_field" pattern="^\d*(\.\d{0,2})?$" />

JS / JQuery:

$(document).on('keydown', 'input[pattern]', function(e){
  var input = $(this);
  var oldVal = input.val();
  var regex = new RegExp(input.attr('pattern'), 'g');

  setTimeout(function(){
    var newVal = input.val();
    if(!regex.test(newVal)){
      input.val(oldVal); 
    }
  }, 0);
});

Update

setTimeout is not working correctly anymore for this, maybe browsers have changed. Some other async solution will need to be devised.

javax.naming.NameNotFoundException: Name is not bound in this Context. Unable to find

Ok found out the Tomcat file server.xml must be configured as well for the data source to work. So just add:

<Resource 
auth="Container" 
driverClassName="org.apache.derby.jdbc.EmbeddedDriver" 
maxActive="20" 
maxIdle="10" 
maxWait="-1" 
name="ds/flexeraDS" 
type="javax.sql.DataSource" 
url="jdbc:derby:flexeraDB;create=true" 
  />

Split string into individual words Java

String[] str = s.split("[^a-zA-Z]+");

RegEx to parse or validate Base64 data

The best regexp which I could find up till now is in here https://www.npmjs.com/package/base64-regex

which is in the current version looks like:

module.exports = function (opts) {
  opts = opts || {};
  var regex = '(?:[A-Za-z0-9+\/]{4}\\n?)*(?:[A-Za-z0-9+\/]{2}==|[A-Za-z0-9+\/]{3}=)';

  return opts.exact ? new RegExp('(?:^' + regex + '$)') :
                    new RegExp('(?:^|\\s)' + regex, 'g');
};

Define variable to use with IN operator (T-SQL)

DECLARE @MyList TABLE (Value INT)
INSERT INTO @MyList VALUES (1)
INSERT INTO @MyList VALUES (2)
INSERT INTO @MyList VALUES (3)
INSERT INTO @MyList VALUES (4)

SELECT *
FROM MyTable
WHERE MyColumn IN (SELECT Value FROM @MyList)

check the null terminating character in char*

You have used '/0' instead of '\0'. This is incorrect: the '\0' is a null character, while '/0' is a multicharacter literal.

Moreover, in C it is OK to skip a zero in your condition:

while (*(forward++)) {
    ...
}

is a valid way to check character, integer, pointer, etc. for being zero.

Can't find bundle for base name

java.util.MissingResourceException: Can't find bundle for base name
    org.jfree.chart.LocalizationBundle, locale en_US

To the point, the exception message tells in detail that you need to have either of the following files in the classpath:

/org/jfree/chart/LocalizationBundle.properties

or

/org/jfree/chart/LocalizationBundle_en.properties

or

/org/jfree/chart/LocalizationBundle_en_US.properties

Also see the official Java tutorial about resourcebundles for more information.

But as this is actually a 3rd party managed properties file, you shouldn't create one yourself. It should be already available in the JFreeChart JAR file. So ensure that you have it available in the classpath during runtime. Also ensure that you're using the right version, the location of the propertiesfile inside the package tree might have changed per JFreeChart version.

When executing a JAR file, you can use the -cp argument to specify the classpath. E.g.:

java -jar -cp c:/path/to/jfreechart.jar yourfile.jar

Alternatively you can specify the classpath as class-path entry in the JAR's manifest file. You can use in there relative paths which are relative to the JAR file itself. Do not use the %CLASSPATH% environment variable, it's ignored by JAR's and everything else which aren't executed with java.exe without -cp, -classpath and -jar arguments.

How to have an auto incrementing version number (Visual Studio)?

Here's the quote on AssemblyInfo.cs from MSDN:

You can specify all the values or you can accept the default build number, revision number, or both by using an asterisk (). For example, [assembly:AssemblyVersion("2.3.25.1")] indicates 2 as the major version, 3 as the minor version, 25 as the build number, and 1 as the revision number. A version number such as [assembly:AssemblyVersion("1.2.")] specifies 1 as the major version, 2 as the minor version, and accepts the default build and revision numbers. A version number such as [assembly:AssemblyVersion("1.2.15.*")] specifies 1 as the major version, 2 as the minor version, 15 as the build number, and accepts the default revision number. The default build number increments daily. The default revision number is random

This effectively says, if you put a 1.1.* into assembly info, only build number will autoincrement, and it will happen not after every build, but daily. Revision number will change every build, but randomly, rather than in an incrementing fashion.

This is probably enough for most use cases. If that's not what you're looking for, you're stuck with having to write a script which will autoincrement version # on pre-build step

How to break lines in PowerShell?

Try "`n" with double quotes. (not single quotes '`n' )

For a complete list of escaping characters see:

Help about_Escape_character

The code should be

$str += "`n"

SQL subquery with COUNT help

SELECT e.*,
       cnt.colCount 
FROM eventsTable e
INNER JOIN (
           select columnName,count(columnName) as colCount
           from eventsTable e2 
          group by columnName
           ) as cnt on cnt.columnName = e.columnName
WHERE e.columnName='Business'

-- Added space

CGContextDrawImage draws image upside down when passed UIImage.CGImage

Relevant Quartz2D docs: https://developer.apple.com/library/ios/documentation/2DDrawing/Conceptual/DrawingPrintingiOS/GraphicsDrawingOverview/GraphicsDrawingOverview.html#//apple_ref/doc/uid/TP40010156-CH14-SW4

Flipping the Default Coordinate System

Flipping in UIKit drawing modifies the backing CALayer to align a drawing environment having a LLO coordinate system with the default coordinate system of UIKit. If you only use UIKit methods and function for drawing, you shouldn’t need to flip the CTM. However, if you mix Core Graphics or Image I/O function calls with UIKit calls, flipping the CTM might be necessary.

Specifically, if you draw an image or PDF document by calling Core Graphics functions directly, the object is rendered upside-down in the view’s context. You must flip the CTM to display the image and pages correctly.

To flip a object drawn to a Core Graphics context so that it appears correctly when displayed in a UIKit view, you must modify the CTM in two steps. You translate the origin to the upper-left corner of the drawing area, and then you apply a scale translation, modifying the y-coordinate by -1. The code for doing this looks similar to the following:

CGContextSaveGState(graphicsContext);
CGContextTranslateCTM(graphicsContext, 0.0, imageHeight);
CGContextScaleCTM(graphicsContext, 1.0, -1.0);
CGContextDrawImage(graphicsContext, image, CGRectMake(0, 0, imageWidth, imageHeight));
CGContextRestoreGState(graphicsContext);

HTML form readonly SELECT tag/input

very simple. First store value in variable. Then on change event set value to stored variable that holds initial value of

I have a whose name is mapping. Then my code will be as follows;

$("document").ready(function(){ 
    var mapping=$("select[name=mapping]").val();
    $("select[name=mapping]").change(function(){
        $("select[name=mapping]").val(mapping);
    });
});

How do I delete rows in a data frame?

Create id column in your data frame or use any column name to identify the row. Using index is not fair to delete.

Use subset function to create new frame.

updated_myData <- subset(myData, id!= 6)
print (updated_myData)

updated_myData <- subset(myData, id %in% c(1, 3, 5, 7))
print (updated_myData)

Windows Batch: How to add Host-Entries?

I would do it this way, so you won't end up with duplicate entries if the script is run multiple times.

@echo off

SET NEWLINE=^& echo.

FIND /C /I "ns1.intranet.de" %WINDIR%\system32\drivers\etc\hosts
IF %ERRORLEVEL% NEQ 0 ECHO %NEWLINE%^62.116.159.4 ns1.intranet.de>>%WINDIR%\System32\drivers\etc\hosts

FIND /C /I "ns2.intranet.de" %WINDIR%\system32\drivers\etc\hosts
IF %ERRORLEVEL% NEQ 0 ECHO %NEWLINE%^217.160.113.37 ns2.intranet.de>>%WINDIR%\System32\drivers\etc\hosts

FIND /C /I "ns3.intranet.de" %WINDIR%\system32\drivers\etc\hosts
IF %ERRORLEVEL% NEQ 0 ECHO %NEWLINE%^89.146.248.4 ns3.intranet.de>>%WINDIR%\System32\drivers\etc\hosts

FIND /C /I "ns4.intranet.de" %WINDIR%\system32\drivers\etc\hosts
IF %ERRORLEVEL% NEQ 0 ECHO %NEWLINE%^74.208.254.4 ns4.intranet.de>>%WINDIR%\System32\drivers\etc\hosts

Force browser to download image files on click

Try this:

<a class="button" href="http://www.glamquotes.com/wp-content/uploads/2011/11/smile.jpg" download="smile.jpg">Download image</a>

Intro to GPU programming

OpenCL is an effort to make a cross-platform library capable of programming code suitable for, among other things, GPUs. It allows one to write the code without knowing what GPU it will run on, thereby making it easier to use some of the GPU's power without targeting several types of GPU specifically. I suspect it's not as performant as native GPU code (or as native as the GPU manufacturers will allow) but the tradeoff can be worth it for some applications.

It's still in its relatively early stages (1.1 as of this answer), but has gained some traction in the industry - for instance it is natively supported on OS X 10.5 and above.

How to replace (null) values with 0 output in PIVOT

I have encountered similar problem. The root cause is that (use your scenario for my case), in the #temp table, there is no record for
a. CLASS=RICE and STATE=TX
b. CLASS=VEGIE and (STATE=AZ or STATE=CA)
So, when MSSQL does pivot for no record, MSSQL always shows NULL for MAX, SUM, ... (aggregate functions)

None of above solutions (IsNull([AZ], 0)) works for me. But I do get ideas from these solutions. Thanks.

Sorry, it really depends on the #TEMP table. I can only provide some suggestions.
1. Make sure #TEMP table have records for below condition, even Data is null.
a. CLASS=RICE and STATE=TX
b. CLASS=VEGIE and (STATE=AZ or STATE=CA) You may need to use cartesian product: select A.*, B.* from A, B 2. In the select query for #temp, if you need to join any table with WHERE, then would better put where inside another sub select query. (Goal is 1.)
3. Use isnull(DATA, 0) in #TEMP table.
4. Before pivot, make sure you have achieved Goal 1.

I can't give an answer to the orginal question, since there is no enough info for #temp table. I have pasted my code as example here, hope this will help others.

_x000D_
_x000D_
SELECT * FROM (_x000D_
   SELECT eeee.id as enterprise_id_x000D_
   , eeee.name AS enterprise_name_x000D_
   , eeee.indicator_name_x000D_
   , CONVERT(varchar(12) , isnull(eid.[date],'2019-12-01') , 23) AS data_date_x000D_
   , isnull(eid.value,0) AS indicator_value_x000D_
   FROM (select ei.id as indicator_id, ei.name as indicator_name, e.* FROM tbl_enterprise_indicator ei, tbl_enterprise e) eeee            _x000D_
   LEFT JOIN  (select * from tbl_enterprise_indicator_data WHERE [date]='2020-01-01') eid_x000D_
     ON  eeee.id = eid.enterprise_id and eeee.indicator_id = enterprise_indicator_id_x000D_
  ) AS P _x000D_
  PIVOT _x000D_
  (_x000D_
   SUM(P.indicator_value) FOR P.indicator_name IN(TX,CA)_x000D_
  ) AS T 
_x000D_
_x000D_
_x000D_

Cancel a UIView animation?

To pause an animation without reverting state to original or final:

CFTimeInterval paused_time = [myView.layer convertTime:CACurrentMediaTime() fromLayer:nil];
myView.layer.speed = 0.0;
myView.layer.timeOffset = paused_time;