incompatible character encodings: ASCII-8BIT and UTF-8

The problem was the use of incorrect quotes around the iOS version. Make sure all your quotes are ' and not ‘ or ’.

https://github.com/CocoaPods/CocoaPods/issues/829

JSON string to JS object

You can use this library from JSON.org to translate your string into a JSON object.

var var1_obj = JSON.parse(var1);

Or you can use the jquery-json library as well.

var var1_obj = $.toJSON(var1);

An example of how to use getopts in bash

#!/bin/bash

usage() { echo "Usage: $0 [-s <45|90>] [-p <string>]" 1>&2; exit 1; }

while getopts ":s:p:" o; do
    case "${o}" in
        s)
            s=${OPTARG}
            ((s == 45 || s == 90)) || usage
            ;;
        p)
            p=${OPTARG}
            ;;
        *)
            usage
            ;;
    esac
done
shift $((OPTIND-1))

if [ -z "${s}" ] || [ -z "${p}" ]; then
    usage
fi

echo "s = ${s}"
echo "p = ${p}"

Example runs:

$ ./myscript.sh
Usage: ./myscript.sh [-s <45|90>] [-p <string>]

$ ./myscript.sh -h
Usage: ./myscript.sh [-s <45|90>] [-p <string>]

$ ./myscript.sh -s "" -p ""
Usage: ./myscript.sh [-s <45|90>] [-p <string>]

$ ./myscript.sh -s 10 -p foo
Usage: ./myscript.sh [-s <45|90>] [-p <string>]

$ ./myscript.sh -s 45 -p foo
s = 45
p = foo

$ ./myscript.sh -s 90 -p bar
s = 90
p = bar

A good example of a situation when @see can be useful would be implementing or overriding an interface/abstract class method. The declaration would have javadoc section detailing the method and the overridden/implemented method could use a @see tag, referring to the base one.

Related question: Writing proper javadoc with @see?

Java SE documentation: @see

Convert date to day name e.g. Mon, Tue, Wed

Your code works for me

$date = '15-12-2016';
$nameOfDay = date('D', strtotime($date));
echo $nameOfDay;

Use l instead of D, if you prefer the full textual representation of the name

How to make a pure css based dropdown menu?

You don't have to always use ul elements to achieve that, you can use other elements too as seen below. Here there are 2 examples, one using div and one using select.

This examples demonstrates the basic functionality, but can be extended/enriched more. It is tested in linux only (iceweasel and chrome).

<!DOCTYPE html>
<html>
<head>
<meta charset='UTF-8'>
<style>
.drop_container
{
  position:relative;
  float:left;
}
.always_visible
{
  background-color:#FAFAFA;
  color:#333333;
  font-weight:bold;
  cursor:pointer;
  border:2px silver solid;
  margin:0px;
  margin-right:5px;
  font-size:14px;
  font-family:"Times New Roman", Times, serif;
}
.always_visible:hover + .hidden_container
{
  display:block;
  position:absolute;
  color:green;
}
.hidden_container
{
  display:none;
  border:1px gray solid;
  left:0px;
  background-color:#FAFAFA;
  padding:5px;
  z-index:1;
}
.hidden_container:hover
{
  display:block;
  position:absolute;
}
.link
{
  color:blue;
  white-space:nowrap;
  margin:3px;
  display:block;
}
.link:hover
{
  color:white;
  background-color:blue;
}
.line_1
{
  width:800px;
  border:1px tomato solid;
  padding:5px;
}
</style>      
</head>

<body>

<div class="line_1">
<div class="drop_container">
  <select class="always_visible" disabled><option>Select</option></select>
  <div class="hidden_container">
  <a href="http://www.google.gr" class="link">Option_ 1</a>
  <a href="http://www.google.gr" class="link">Option__ 2</a>
  <a href="http://www.google.gr" class="link">Option___ 3</a>
  <a href="http://www.google.gr" class="link">Option____ 4</a>
  </div>
</div>
<div class="drop_container">
  <select class="always_visible" disabled><option>Select</option></select>
  <div class="hidden_container">
  <a href="http://www.google.gr" class="link">____1</a>
  <a href="http://www.google.gr" class="link">___2</a>
  <a href="http://www.google.gr" class="link">__3</a>
  <a href="http://www.google.gr" class="link">_4</a>
  </div>
</div>
<div style="clear:both;"></div>
</div>

<br>

<div class="line_1">
 <div class="drop_container">
  <div class="always_visible">Select___</div>
  <div class="hidden_container">
  <a href="http://www.google.gr" class="link">Option_ 1</a>
  <a href="http://www.google.gr" class="link">Option__ 2</a>
  <a href="http://www.google.gr" class="link">Option___ 3</a>
  <a href="http://www.google.gr" class="link">Option____ 4</a>
  </div>
</div>
 <div class="drop_container">
  <div class="always_visible">Select___</div>
  <div class="hidden_container">
  <a href="http://www.google.gr" class="link">Option_ 1</a>
  <a href="http://www.google.gr" class="link">Option__ 2</a>
  <a href="http://www.google.gr" class="link">Option___ 3</a>
  <a href="http://www.google.gr" class="link">Option____ 4</a>
  </div>
</div>
<div style="clear:both;"></div>
</div>

</body>
</html>

Google Authenticator available as a public service?

You can use my solution, posted as the answer to my question (there is full Python code and explanation):

Google Authenticator implementation in Python

It is rather easy to implement it in PHP or Perl, I think. If you have any problems with this, please let me know.

I have also posted my code on GitHub as Python module.

SQL DELETE with JOIN another table for WHERE condition

Due to the locking implementation issues, MySQL does not allow referencing the affected table with DELETE or UPDATE.

You need to make a JOIN here instead:

DELETE  gc.*
FROM    guide_category AS gc 
LEFT JOIN
        guide AS g 
ON      g.id_guide = gc.id_guide
WHERE   g.title IS NULL

or just use a NOT IN:

DELETE  
FROM    guide_category AS gc 
WHERE   id_guide NOT IN
        (
        SELECT  id_guide
        FROM    guide
        )

How to Auto-start an Android Application?

Edit your AndroidManifest.xml to add RECEIVE_BOOT_COMPLETED permission

<uses-permission android:name="android.permission.RECEIVE_BOOT_COMPLETED" />

Edit your AndroidManifest.xml application-part for below Permission

<receiver android:enabled="true" android:name=".BootUpReceiver"
android:permission="android.permission.RECEIVE_BOOT_COMPLETED">
    <intent-filter>
        <action android:name="android.intent.action.BOOT_COMPLETED" />
        <category android:name="android.intent.category.DEFAULT" />
    </intent-filter>
</receiver>

Now write below in Activity.

public class BootUpReceiver extends BroadcastReceiver{
    @Override
    public void onReceive(Context context, Intent intent) {
        Intent i = new Intent(context, MyActivity.class);  
        i.addFlags(Intent.FLAG_ACTIVITY_NEW_TASK);
        context.startActivity(i);  
    }
}

Telling Python to save a .txt file to a certain directory on Windows and Mac

Using an absolute or relative string as the filename.

name_of_file = input("What is the name of the file: ")
completeName = '/home/user/Documents'+ name_of_file + ".txt"
file1 = open(completeName , "w")
toFile = input("Write what you want into the field")
file1.write(toFile)
file1.close()

This IP, site or mobile application is not authorized to use this API key

For the latest version of the API the exact opposite seems to be true for me.

When calling the url https://maps.googleapis.com/maps/api/geocode/json?address=<address>&key=<key> I was getting the following error

You must use an API key to authenticate each request to Google Maps Platform APIs. For additional information, please refer to http://g.co/dev/maps-no-account

Once I switched the order to https://maps.googleapis.com/maps/api/geocode/json?key=<key>&address=<address> it worked fine.

Note that the error message received above was the message I got when going directly to the URL in the browser. When I called the API from a software program I received an HTML response with basically the following message:

We're sorry... but your computer or network may be sending automated queries. To protect our users, we can't process your request right now.

Xcode stops working after set "xcode-select -switch"

You should be pointing it towards the Developer directory, not the Xcode application bundle. Run this:

sudo xcode-select --switch /Applications/Xcode.app/Contents/Developer

With recent versions of Xcode, you can go to Xcode ? Preferences… ? Locations and pick one of the options for Command Line Tools to set the location.

Dynamically replace img src attribute with jQuery

In my case, I replaced the src taq using:

_x000D_

   $('#gmap_canvas').attr('src', newSrc);

_x000D_

How to set Sqlite3 to be case insensitive when string comparing?

You can use COLLATE NOCASE in your SELECT query:

SELECT * FROM ... WHERE name = 'someone' COLLATE NOCASE

Additionaly, in SQLite, you can indicate that a column should be case insensitive when you create the table by specifying collate nocase in the column definition (the other options are binary (the default) and rtrim; see here). You can specify collate nocase when you create an index as well. For example:

create table Test
(
  Text_Value  text collate nocase
);

insert into Test values ('A');
insert into Test values ('b');
insert into Test values ('C');

create index Test_Text_Value_Index
  on Test (Text_Value collate nocase);

Expressions involving Test.Text_Value should now be case insensitive. For example:

sqlite> select Text_Value from Test where Text_Value = 'B';
Text_Value      
----------------
b               

sqlite> select Text_Value from Test order by Text_Value;
Text_Value      
----------------
A               
b               
C    

sqlite> select Text_Value from Test order by Text_Value desc;
Text_Value      
----------------
C               
b               
A

The optimiser can also potentially make use of the index for case-insensitive searching and matching on the column. You can check this using the explain SQL command, e.g.:

sqlite> explain select Text_Value from Test where Text_Value = 'b';
addr              opcode          p1          p2          p3                               
----------------  --------------  ----------  ----------  ---------------------------------
0                 Goto            0           16                                           
1                 Integer         0           0                                            
2                 OpenRead        1           3           keyinfo(1,NOCASE)                
3                 SetNumColumns   1           2                                            
4                 String8         0           0           b                                
5                 IsNull          -1          14                                           
6                 MakeRecord      1           0           a                                
7                 MemStore        0           0                                            
8                 MoveGe          1           14                                           
9                 MemLoad         0           0                                            
10                IdxGE           1           14          +                                
11                Column          1           0                                            
12                Callback        1           0                                            
13                Next            1           9                                            
14                Close           1           0                                            
15                Halt            0           0                                            
16                Transaction     0           0                                            
17                VerifyCookie    0           4                                            
18                Goto            0           1                                            
19                Noop            0           0

IOError: [Errno 32] Broken pipe: Python

Closes should be done in reverse order of the opens.

How to iterate over array of objects in Handlebars?

I meant in the template() call..

You just need to pass the results as an object. So instead of calling

var html = template(data);

var html = template({apidata: data});

and use {{#each apidata}} in your template code

demo at http://jsfiddle.net/KPCh4/4/
(removed some leftover if code that crashed)

Postgres and Indexes on Foreign Keys and Primary Keys

If you want to list the indexes of all the tables in your schema(s) from your program, all the information is on hand in the catalog:

select
     n.nspname  as "Schema"
    ,t.relname  as "Table"
    ,c.relname  as "Index"
from
          pg_catalog.pg_class c
     join pg_catalog.pg_namespace n on n.oid        = c.relnamespace
     join pg_catalog.pg_index i     on i.indexrelid = c.oid
     join pg_catalog.pg_class t     on i.indrelid   = t.oid
where
        c.relkind = 'i'
    and n.nspname not in ('pg_catalog', 'pg_toast')
    and pg_catalog.pg_table_is_visible(c.oid)
order by
     n.nspname
    ,t.relname
    ,c.relname

If you want to delve further (such as columns and ordering), you need to look at pg_catalog.pg_index. Using psql -E [dbname] comes in handy for figuring out how to query the catalog.

Detect current device with UI_USER_INTERFACE_IDIOM() in Swift

Try this for check current device is iPhone or iPad:

Swift 5

struct Device {
    static let IS_IPAD = UIDevice.current.userInterfaceIdiom == .pad
    static let IS_IPHONE = UIDevice.current.userInterfaceIdiom == .phone
}

Use:

if(Device.IS_IPHONE){
    // device is iPhone
}if(Device.IS_IPAD){
    // device is iPad (or a Mac running under macOS Catalyst)
}else{
    // other
}

Submit a form using jQuery

The solutions so far require you to know the ID of the form.

Use this code to submit the form without needing to know the ID:

function handleForm(field) {
    $(field).closest("form").submit();
}

For example if you were wanting to handle the click event for a button, you could use

$("#buttonID").click(function() {
    handleForm(this);    
});

What is the best way to detect a mobile device?

If by "mobile" you mean "small screen," I use this:

var windowWidth = window.screen.width < window.outerWidth ?
                  window.screen.width : window.outerWidth;
var mobile = windowWidth < 500;

On iPhone you'll end up with a window.screen.width of 320. On Android you'll end up with a window.outerWidth of 480 (though that can depend on the Android). iPads and Android tablets will return numbers like 768 so they'll get the full view like you'd want.

PHP UML Generator

Have you tried Autodia yet? Last time I tried it it wasn't perfect, but it was good enough.

Difference between thread's context class loader and normal classloader

This does not answer the original question, but as the question is highly ranked and linked for any ContextClassLoader query, I think it is important to answer the related question of when the context class loader should be used. Short answer: never use the context class loader! But set it to getClass().getClassLoader() when you have to call a method that is missing a ClassLoader parameter.

When code from one class asks to load another class, the correct class loader to use is the same class loader as the caller class (i.e., getClass().getClassLoader()). This is the way things work 99.9% of the time because this is what the JVM does itself the first time you construct an instance of a new class, invoke a static method, or access a static field.

When you want to create a class using reflection (such as when deserializing or loading a configurable named class), the library that does the reflection should always ask the application which class loader to use, by receiving the ClassLoader as a parameter from the application. The application (which knows all the classes that need constructing) should pass it getClass().getClassLoader().

Any other way to obtain a class loader is incorrect. If a library uses hacks such as Thread.getContextClassLoader(), sun.misc.VM.latestUserDefinedLoader(), or sun.reflect.Reflection.getCallerClass() it is a bug caused by a deficiency in the API. Basically, Thread.getContextClassLoader() exists only because whoever designed the ObjectInputStream API forgot to accept the ClassLoader as a parameter, and this mistake has haunted the Java community to this day.

That said, many many JDK classes use one of a few hacks to guess some class loader to use. Some use the ContextClassLoader (which fails when you run different apps on a shared thread pool, or when you leave the ContextClassLoader null), some walk the stack (which fails when the direct caller of the class is itself a library), some use the system class loader (which is fine, as long as it is documented to only use classes in the CLASSPATH) or bootstrap class loader, and some use an unpredictable combination of the above techniques (which only makes things more confusing). This has resulted in much weeping and gnashing of teeth.

When using such an API, first, try to find an overload of the method that accepts the class loader as a parameter. If there is no sensible method, then try setting the ContextClassLoader before the API call (and resetting it afterwards):

ClassLoader originalClassLoader = Thread.currentThread().getContextClassLoader();
try {
    Thread.currentThread().setContextClassLoader(getClass().getClassLoader());
    // call some API that uses reflection without taking ClassLoader param
} finally {
    Thread.currentThread().setContextClassLoader(originalClassLoader);
}

Is there a foreach loop in Go?

Yes, Range :

The range form of the for loop iterates over a slice or map.

When ranging over a slice, two values are returned for each iteration. The first is the index, and the second is a copy of the element at that index.

Example :

package main

import "fmt"

var pow = []int{1, 2, 4, 8, 16, 32, 64, 128}

func main() {
    for i, v := range pow {
        fmt.Printf("2**%d = %d\n", i, v)
    }

    for i := range pow {
        pow[i] = 1 << uint(i) // == 2**i
    }
    for _, value := range pow {
        fmt.Printf("%d\n", value)
    }
}

You can skip the index or value by assigning to _.
If you only want the index, drop the , value entirely.

Make div stay at bottom of page's content all the time even when there are scrollbars

I've solved a similar issue by putting all of my main content within an extra div tag (id="outer"). I've then moved the div tag with id="footer" outside of this last "outer" div tag. I've used CSS to specify the height of "outer" and specified the width and height of "footer". I've also used CSS to specify the margin-left and margin-right of "footer" as auto. The result is that the footer sits firmly at the bottom of my page and scrolls with the page too (although, it's still appears inside the "outer" div, but happily outside of the main "content" div. which seems strange, but it's where I want it).

Docker how to change repository name or rename image?

docker image tag server:latest myname/server:latest

docker image tag d583c3ac45fd myname/server:latest

Tags are just human-readable aliases for the full image name (d583c3ac45fd...).

So you can have as many of them associated with the same image as you like. If you don't like the old name you can remove it after you've retagged it:

docker rmi server

That will just remove the alias/tag. Since d583c3ac45fd has other names, the actual image won't be deleted.

Upload DOC or PDF using PHP

Don't use the ['type'] parameter to validate uploads. That field is user-provided, and can be trivially forged, allowing ANY type of file to be uploaded. The same goes for the ['name'] parameter - that's the name of the file as provided by the user. It is also trivial to forge, so the user's sending nastyvirus.exe and calling it cutekittens.jpg.

The proper method for validating uploads is to use server-side mime-type determination, e.g. via fileinfo, plus having proper upload success checking, which you do not:

if ($_FILES['file']['error'] !== UPLOAD_ERR_OK) {
    die("Upload failed with error " . $_FILES['file']['error']);
}
$finfo = finfo_open(FILEINFO_MIME_TYPE);
$mime = finfo_file($finfo, $_FILES['file']['tmp_name']);
$ok = false;
switch ($mime) {
   case 'image/jpeg':
   case 'application/pdf'
   case etc....
        $ok = true;
   default:
       die("Unknown/not permitted file type");
}
move_uploaded_file(...);

You are also using the user-provided filename as part of the final destination of the move_uploaded_files. it is also trivial to embed path data into that filename, which you then blindly use. That means a malicious remote user can scribble on ANY file on your server that they know the path for, plus plant new files.

Using async/await with a forEach loop

One important caveat is: The await + for .. of method and the forEach + async way actually have different effect.

Having await inside a real for loop will make sure all async calls are executed one by one. And the forEach + async way will fire off all promises at the same time, which is faster but sometimes overwhelmed(if you do some DB query or visit some web services with volume restrictions and do not want to fire 100,000 calls at a time).

You can also use reduce + promise(less elegant) if you do not use async/await and want to make sure files are read one after another.

files.reduce((lastPromise, file) => 
 lastPromise.then(() => 
   fs.readFile(file, 'utf8')
 ), Promise.resolve()
)

Or you can create a forEachAsync to help but basically use the same for loop underlying.

Array.prototype.forEachAsync = async function(cb){
    for(let x of this){
        await cb(x);
    }
}

Catch a thread's exception in the caller thread in Python

As a noobie to Threading, it took me a long time to understand how to implement Mateusz Kobos's code (above). Here's a clarified version to help understand how to use it.

#!/usr/bin/env python

import sys
import threading
import Queue

class ExThread(threading.Thread):
    def __init__(self):
        threading.Thread.__init__(self)
        self.__status_queue = Queue.Queue()

    def run_with_exception(self):
        """This method should be overriden."""
        raise NotImplementedError

    def run(self):
        """This method should NOT be overriden."""
        try:
            self.run_with_exception()
        except Exception:
            self.__status_queue.put(sys.exc_info())
        self.__status_queue.put(None)

    def wait_for_exc_info(self):
        return self.__status_queue.get()

    def join_with_exception(self):
        ex_info = self.wait_for_exc_info()
        if ex_info is None:
            return
        else:
            raise ex_info[1]

class MyException(Exception):
    pass

class MyThread(ExThread):
    def __init__(self):
        ExThread.__init__(self)

    # This overrides the "run_with_exception" from class "ExThread"
    # Note, this is where the actual thread to be run lives. The thread
    # to be run could also call a method or be passed in as an object
    def run_with_exception(self):
        # Code will function until the int
        print "sleeping 5 seconds"
        import time
        for i in 1, 2, 3, 4, 5:
            print i
            time.sleep(1) 
        # Thread should break here
        int("str")
# I'm honestly not sure why these appear here? So, I removed them. 
# Perhaps Mateusz can clarify?        
#         thread_name = threading.current_thread().name
#         raise MyException("An error in thread '{}'.".format(thread_name))

if __name__ == '__main__':
    # The code lives in MyThread in this example. So creating the MyThread 
    # object set the code to be run (but does not start it yet)
    t = MyThread()
    # This actually starts the thread
    t.start()
    print
    print ("Notice 't.start()' is considered to have completed, although" 
           " the countdown continues in its new thread. So you code "
           "can tinue into new processing.")
    # Now that the thread is running, the join allows for monitoring of it
    try:
        t.join_with_exception()
    # should be able to be replace "Exception" with specific error (untested)
    except Exception, e: 
        print
        print "Exceptioon was caught and control passed back to the main thread"
        print "Do some handling here...or raise a custom exception "
        thread_name = threading.current_thread().name
        e = ("Caught a MyException in thread: '" + 
             str(thread_name) + 
             "' [" + str(e) + "]")
        raise Exception(e) # Or custom class of exception, such as MyException

How to fix Python Numpy/Pandas installation?

Don't know if you solved the problem but if anyone has this problem in future.

$python
>>import numpy
>>print(numpy)

Go to the location printed and delete the numpy installation found there. You can then use pip or easy_install

fix java.net.SocketTimeoutException: Read timed out

Here are few pointers/suggestions for investigation

I see that every time you vote, you call vote method which creates a fresh HTTP connection.
This might be a problem. I would suggest to use a single HttpClient instance to post to the server. This way it wont create too many connections from the client side.
At the end of everything, HttpClient needs to be shut and hence call httpclient.getConnectionManager().shutdown(); to release the resources used by the connections.

How to add a new schema to sql server 2008?

Use the CREATE SCHEMA syntax or, in SSMS, drill down through Databases -> YourDatabaseName -> Security -> Schemas. Right-click on the Schemas folder and select "New Schema..."

How to check if dropdown is disabled?

The legacy solution, before 1.6, was to use .attr and handle the returned value as a bool. The main problem is that the returned type of .attr has changed to string, and therefore the comparison with == true is broken (see http://jsfiddle.net/2vene/1/ (and switch the jquery-version)).

With 1.6 .prop was introduced, which returns a bool.

Nevertheless, I suggest to use .is(), as the returned type is intrinsically bool, like:

$('#dropUnit').is(':disabled');
$('#dropUnit').is(':enabled');

Furthermore .is() is much more natural (in terms of "natural language") and adds more conditions than a simple attribute-comparison (eg: .is(':last'), .is(':visible'), ... please see documentation on selectors).

How do I create a file at a specific path?

I recommend using the os module to avoid trouble in cross-platform. (windows,linux,mac)

Cause if the directory doesn't exists, it will return an exception.

import os

filepath = os.path.join('c:/your/full/path', 'filename')
if not os.path.exists('c:/your/full/path'):
    os.makedirs('c:/your/full/path')
f = open(filepath, "a")

If this will be a function for a system or something, you can improve it by adding try/except for error control.

Is there a way to create key-value pairs in Bash script?

In bash version 4 associative arrays were introduced.

declare -A arr

arr["key1"]=val1

arr+=( ["key2"]=val2 ["key3"]=val3 )

The arr array now contains the three key value pairs. Bash is fairly limited what you can do with them though, no sorting or popping etc.

for key in ${!arr[@]}; do
    echo ${key} ${arr[${key}]}
done

Will loop over all key values and echo them out.

Note: Bash 4 does not come with Mac OS X because of its GPLv3 license; you have to download and install it. For more on that see here

How to save and load numpy.array() data properly?

For a short answer you should use np.save and np.load. The advantages of these is that they are made by developers of the numpy library and they already work (plus are likely already optimized nicely) e.g.

import numpy as np
from pathlib import Path

path = Path('~/data/tmp/').expanduser()
path.mkdir(parents=True, exist_ok=True)

lb,ub = -1,1
num_samples = 5
x = np.random.uniform(low=lb,high=ub,size=(1,num_samples))
y = x**2 + x + 2

np.save(path/'x', x)
np.save(path/'y', y)

x_loaded = np.load(path/'x.npy')
y_load = np.load(path/'y.npy')

print(x is x_loaded) # False
print(x == x_loaded) # [[ True  True  True  True  True]]

Expanded answer:

In the end it really depends in your needs because you can also save it human readable format (see this Dump a NumPy array into a csv file) or even with other libraries if your files are extremely large (see this best way to preserve numpy arrays on disk for an expanded discussion).

However, (making an expansion since you use the word "properly" in your question) I still think using the numpy function out of the box (and most code!) most likely satisfy most user needs. The most important reason is that it already works. Trying to use something else for any other reason might take you on an unexpectedly LONG rabbit hole to figure out why it doesn't work and force it work.

Take for example trying to save it with pickle. I tried that just for fun and it took me at least 30 minutes to realize that pickle wouldn't save my stuff unless I opened & read the file in bytes mode with wb. Took time to google, try thing, understand the error message etc... Small detail but the fact that it already required me to open a file complicated things in unexpected ways. To add that it required me to re-read this (which btw is sort of confusing) Difference between modes a, a+, w, w+, and r+ in built-in open function?.

So if there is an interface that meets your needs use it unless you have a (very) good reason (e.g. compatibility with matlab or for some reason your really want to read the file and printing in python really doesn't meet your needs, which might be questionable). Furthermore, most likely if you need to optimize it you'll find out later down the line (rather than spend ages debugging useless stuff like opening a simple numpy file).

So use the interface/numpy provide. It might not be perfect it's most likely fine, especially for a library that's been around as long as numpy.

I already spent the saving and loading data with numpy in a bunch of way so have fun with it, hope it helps!

import numpy as np
import pickle
from pathlib import Path

path = Path('~/data/tmp/').expanduser()
path.mkdir(parents=True, exist_ok=True)

lb,ub = -1,1
num_samples = 5
x = np.random.uniform(low=lb,high=ub,size=(1,num_samples))
y = x**2 + x + 2

# using save (to npy), savez (to npz)
np.save(path/'x', x)
np.save(path/'y', y)
np.savez(path/'db', x=x, y=y)
with open(path/'db.pkl', 'wb') as db_file:
    pickle.dump(obj={'x':x, 'y':y}, file=db_file)

## using loading npy, npz files
x_loaded = np.load(path/'x.npy')
y_load = np.load(path/'y.npy')
db = np.load(path/'db.npz')
with open(path/'db.pkl', 'rb') as db_file:
    db_pkl = pickle.load(db_file)

print(x is x_loaded)
print(x == x_loaded)
print(x == db['x'])
print(x == db_pkl['x'])
print('done')

Some comments on what I learned:

np.save as expected, this already compresses it well (see https://stackoverflow.com/a/55750128/1601580), works out of the box without any file opening. Clean. Easy. Efficient. Use it.
np.savez uses a uncompressed format (see docs) Save several arrays into a single file in uncompressed .npz format. If you decide to use this (you were warned to go away from the standard solution so expect bugs!) you might discover that you need to use argument names to save it, unless you want to use the default names. So don't use this if the first already works (or any works use that!)
Pickle also allows for arbitrary code execution. Some people might not want to use this for security reasons.
human readable files are expensive to make etc. Probably not worth it.
there is something called hdf5 for large files. Cool! https://stackoverflow.com/a/9619713/1601580

Note this is not an exhaustive answer. But for other resources check this:

For pickle (guess the top answer is don't use pickle us np.save): Save Numpy Array using Pickle
For large files (great answer! compares storage size, loading save and more!): https://stackoverflow.com/a/41425878/1601580
For matlab (we have to accept matlab has some freakin' nice plots!): "Converting" Numpy arrays to Matlab and vice versa
For saving in human readable format: Dump a NumPy array into a csv file

Java - Convert image to Base64

 byte[] byteArray = new byte[102400];
 base64String = Base64.encode(byteArray);

That code will encode 102400 bytes, no matter how much data you actually use in the array.

while ((bytesRead = fis.read(byteArray)) != -1)

You need to use the value of bytesRead somewhere.

Also, this may not read the whole file into the array in one go (it only reads as much as is in the I/O buffer), so your loop will probably not work, you may end up with half an image in your array.

I'd use Apache Commons IOUtils here:

 Base64.encode(FileUtils.readFileToByteArray(file));

Adding an assets folder in Android Studio

right click on app-->select

New-->Select Folder-->then click on Assets Folder

How can I edit a view using phpMyAdmin 3.2.4?

In your database table list it should show View in Type column. To edit View:

Click on your View in table list
Click on Structure tab
Click on Edit View under Check All

Hope this help

update: in PHPMyAdmin 4.x, it doesn't show View in Type, but you can still recognize it:

In Row column: It had zero Row
In Action column: It had greyed empty button

Of course it may be just an empty table, but when you open the structure, you will know whether it's a table or a view.

Echo newline in Bash prints literal \n

If you're writing scripts and will be echoing newlines as part of other messages several times, a nice cross-platform solution is to put a literal newline in a variable like so:

newline='
'

echo "first line$newlinesecond line"
echo "Error: example error message n${newline}${usage}" >&2 #requires usage to be defined

Creating a data frame from two vectors using cbind

Vectors and matrices can only be of a single type and cbind and rbind on vectors will give matrices. In these cases, the numeric values will be promoted to character values since that type will hold all the values.

(Note that in your rbind example, the promotion happens within the c call:

> c(10, "[]", "[[1,2]]")
[1] "10"      "[]"      "[[1,2]]"

If you want a rectangular structure where the columns can be different types, you want a data.frame. Any of the following should get you what you want:

> x = data.frame(v1=c(10, 20), v2=c("[]", "[]"), v3=c("[[1,2]]","[[1,3]]"))
> x
  v1 v2      v3
1 10 [] [[1,2]]
2 20 [] [[1,3]]
> str(x)
'data.frame':   2 obs. of  3 variables:
 $ v1: num  10 20
 $ v2: Factor w/ 1 level "[]": 1 1
 $ v3: Factor w/ 2 levels "[[1,2]]","[[1,3]]": 1 2

or (using specifically the data.frame version of cbind)

> x = cbind.data.frame(c(10, 20), c("[]", "[]"), c("[[1,2]]","[[1,3]]"))
> x
  c(10, 20) c("[]", "[]") c("[[1,2]]", "[[1,3]]")
1        10            []                 [[1,2]]
2        20            []                 [[1,3]]
> str(x)
'data.frame':   2 obs. of  3 variables:
 $ c(10, 20)              : num  10 20
 $ c("[]", "[]")          : Factor w/ 1 level "[]": 1 1
 $ c("[[1,2]]", "[[1,3]]"): Factor w/ 2 levels "[[1,2]]","[[1,3]]": 1 2

or (using cbind, but making the first a data.frame so that it combines as data.frames do):

> x = cbind(data.frame(c(10, 20)), c("[]", "[]"), c("[[1,2]]","[[1,3]]"))
> x
  c.10..20. c("[]", "[]") c("[[1,2]]", "[[1,3]]")
1        10            []                 [[1,2]]
2        20            []                 [[1,3]]
> str(x)
'data.frame':   2 obs. of  3 variables:
 $ c.10..20.              : num  10 20
 $ c("[]", "[]")          : Factor w/ 1 level "[]": 1 1
 $ c("[[1,2]]", "[[1,3]]"): Factor w/ 2 levels "[[1,2]]","[[1,3]]": 1 2

Formatting text in a TextBlock

a good site, with good explanations:

http://www.wpf-tutorial.com/basic-controls/the-textblock-control-inline-formatting/

here the author gives you good examples for what you are looking for! Overal the site is great for research material plus it covers a great deal of options you have in WPF

Edit

There are different methods to format the text. for a basic formatting (the easiest in my opinion):

    <TextBlock Margin="10" TextWrapping="Wrap">
                    TextBlock with <Bold>bold</Bold>, <Italic>italic</Italic> and <Underline>underlined</Underline> text.
    </TextBlock>

Example 1 shows basic formatting with Bold Itallic and underscored text.

Following includes the SPAN method, with this you van highlight text:

   <TextBlock Margin="10" TextWrapping="Wrap">
                    This <Span FontWeight="Bold">is</Span> a
                    <Span Background="Silver" Foreground="Maroon">TextBlock</Span>
                    with <Span TextDecorations="Underline">several</Span>
                    <Span FontStyle="Italic">Span</Span> elements,
                    <Span Foreground="Blue">
                            using a <Bold>variety</Bold> of <Italic>styles</Italic>
                    </Span>.
   </TextBlock>

Example 2 shows the span function and the different possibilities with it.

For a detailed explanation check the site!

Examples

Plotting categorical data with pandas and matplotlib

You can simply use value_counts with sort option set to False. This will preserve ordering of the categories

df['colour'].value_counts(sort=False).plot.bar(rot=0)

How can I update a single row in a ListView?

The answers are clear and correct, I'll add an idea for CursorAdapter case here.

If youre subclassing CursorAdapter (or ResourceCursorAdapter, or SimpleCursorAdapter), then you get to either implement ViewBinder or override bindView() and newView() methods, these don't receive current list item index in arguments. Therefore, when some data arrives and you want to update relevant visible list items, how do you know their indices?

My workaround was to:

keep a list of all created list item views, add items to this list from newView()
when data arrives, iterate them and see which one needs updating--better than doing notifyDatasetChanged() and refreshing all of them

Due to view recycling the number of view references I'll need to store and iterate will be roughly equal the number of list items visible on screen.

How to determine if object is in array

This function is to check for a unique field. Arg 1: the array with selected data Arg 2: key to check Arg 3: value that must be "validated"

function objectUnique( array, field, value )
{
    var unique = true;
    array.forEach(function ( entry )
    {
        if ( entry[field] == value )
        {
            unique = false;
        }
    });

    return unique;
}

How do you completely remove the button border in wpf?

Try this

<Button BorderThickness="0"  
    Style="{StaticResource {x:Static ToolBar.ButtonStyleKey}}" >...

converting CSV/XLS to JSON?

Take a try on the tiny free tool:

http://keyangxiang.com/csvtojson/

It utilises node.js csvtojson module

How to test code dependent on environment variables using JUnit?

Hope the issue is resolved. I just thought to tell my solution.

Map<String, String> env = System.getenv();
    new MockUp<System>() {
        @Mock           
        public String getenv(String name) 
        {
            if (name.equalsIgnoreCase( "OUR_OWN_VARIABLE" )) {
                return "true";
            }
            return env.get(name);
        }
    };

Get last 30 day records from today date in SQL Server

I dont know why all these complicated answers are on here but this is what I would do

where pdate >= CURRENT_TIMESTAMP -30

OR WHERE CAST(PDATE AS DATE) >= GETDATE() -30

ViewPager and fragments — what's the right way to store fragment's state?

A bit different opinion instead of storing the Fragments yourself just leave it to the FragmentManager and when you need to do something with the fragments look for them in the FragmentManager:

//make sure you have the right FragmentManager 
//getSupportFragmentManager or getChildFragmentManager depending on what you are using to manage this stack of fragments
List<Fragment> fragments = fragmentManager.getFragments();
if(fragments != null) {
   int count = fragments.size();
   for (int x = 0; x < count; x++) {
       Fragment fragment = fragments.get(x);
       //check if this is the fragment we want, 
       //it may be some other inspection, tag etc.
       if (fragment instanceof MyFragment) {
           //do whatever we need to do with it
       }
   }
}

If you have a lot of Fragments and the cost of instanceof check may be not what you want, but it is good thing to have in mind that the FragmentManager already keeps account of Fragments.

Can I define a class name on paragraph using Markdown?

Here is a working example for kramdown following @Yarin's answer.

A simple paragraph with a class attribute.
{:.yourClass}

Reference: https://kramdown.gettalong.org/syntax.html#inline-attribute-lists

Default FirebaseApp is not initialized

If you're using Xamarin and came here searching for a solution for this problem, here it's from Microsoft:

In some cases, you may see this error message: Java.Lang.IllegalStateException: Default FirebaseApp is not initialized in this process Make sure to call FirebaseApp.initializeApp(Context) first.

This is a known problem that you can work around by cleaning the solution and rebuilding the project (Build > Clean Solution, Build > Rebuild Solution).

How to return images in flask response?

You use something like

from flask import send_file

@app.route('/get_image')
def get_image():
    if request.args.get('type') == '1':
       filename = 'ok.gif'
    else:
       filename = 'error.gif'
    return send_file(filename, mimetype='image/gif')

to send back ok.gif or error.gif, depending on the type query parameter. See the documentation for the send_file function and the request object for more information.

Conversion from Long to Double in Java

You could simply do :

double d = (double)15552451L;

Or you could get double from Long object as :

Long l = new Long(15552451L);
double d = l.doubleValue();

Git - remote: Repository not found

Remove the all github.com credential details from the system.

For mac

Delete the github.com password from the Keychain Access.

For window

Delete the credentials from Credential Manager.

How can a Javascript object refer to values in itself?

You can't refer to a property of an object before you have initialized that object; use an external variable.

var key1 = "it";
var obj = {
  key1 : key1,
  key2 : key1 + " works!"
};

Also, this is not a "JSON object"; it is a Javascript object. JSON is a method of representing an object with a string (which happens to be valid Javascript code).

Setting max-height for table cell contents

Another way around it that may/may not suit but surely the simplest:

td {
    display: table-caption;
}

Insert HTML with React Variable Statements (JSX)

You can use dangerouslySetInnerHTML, e.g.

render: function() {
    return (
        <div className="content" dangerouslySetInnerHTML={{__html: thisIsMyCopy}}></div>
    );
}

Regex - Should hyphens be escaped?

Correct on all fronts. Outside of a character class (that's what the "square brackets" are called) the hyphen has no special meaning, and within a character class, you can place a hyphen as the first or last character in the range (e.g. [-a-z] or [0-9-]), OR escape it (e.g. [a-z\-0-9]) in order to add "hyphen" to your class.

It's more common to find a hyphen placed first or last within a character class, but by no means will you be lynched by hordes of furious neckbeards for choosing to escape it instead.

(Actually... my experience has been that a lot of regex is employed by folks who don't fully grok the syntax. In these cases, you'll typically see everything escaped (e.g. [a-z\%\$\#\@\!\-\_]) simply because the engineer doesn't know what's "special" and what's not... so they "play it safe" and obfuscate the expression with loads of excessive backslashes. You'll be doing yourself, your contemporaries, and your posterity a huge favor by taking the time to really understand regex syntax before using it.)

Great question!

How to capitalize the first letter in a String in Ruby

capitalize first letter of first word of string

"kirk douglas".capitalize
#=> "Kirk douglas"

capitalize first letter of each word

In rails:

"kirk douglas".titleize
=> "Kirk Douglas"

"kirk_douglas".titleize
=> "Kirk Douglas"

In ruby:

"kirk douglas".split(/ |\_|\-/).map(&:capitalize).join(" ") 
#=> "Kirk Douglas"

require 'active_support/core_ext'
"kirk douglas".titleize

How do I import a Swift file from another Swift file?

Check target-membership of PrimeNumberModel.swift in your testing target.

NullPointerException: Attempt to invoke virtual method 'boolean java.lang.String.equalsIgnoreCase(java.lang.String)' on a null object reference

This is the error line:

if (called_from.equalsIgnoreCase("add")) {  --->38th error line

This means that called_from is null. Simple check if it is null above:

String called_from = getIntent().getStringExtra("called");

if(called_from == null) {
    called_from = "empty string";
}
if (called_from.equalsIgnoreCase("add")) {
    // do whatever
} else {
    // do whatever
}

That way, if called_from is null, it'll execute the else part of your if statement.

Change language of Visual Studio 2017 RC

Go to Tools -> Options
Select International Settings in Environment and on the right side of a screen you should see a combo with the list of installed language packages. (so in my case Czech, English and same as on MS Windows )
Click on Ok

You have to restart Visual Studio to see the change...

If you are polish (and got polish language settings)

Narzedzia -> Opcje
Ustawienia miedzynarodowe in Srodowisko

Hope this helps! Have a great time in Poland!

How to find event listeners on a DOM node when debugging or from the JavaScript code?

If you have Firebug, you can use console.dir(object or array) to print a nice tree in the console log of any JavaScript scalar, array, or object.

Try:

console.dir(clickEvents);

console.dir(window);

Way to insert text having ' (apostrophe) into a SQL table

I know the question is aimed at the direct escaping of the apostrophe character but I assume that usually this is going to be triggered by some sort of program providing the input.

What I have done universally in the scripts and programs I have worked with is to substitute it with a ` character when processing the formatting of the text being input.

Now I know that in some cases, the backtick character may in fact be part of what you might be trying to save (such as on a forum like this) but if you're simply saving text input from users it's a possible solution.

Going into the SQL database

$newval=~s/\'/`/g;

Then, when coming back out for display, filtered again like this:

$showval=~s/`/\'/g;

This example was when PERL/CGI is being used but it can apply to PHP and other bases as well. I have found it works well because I think it helps prevent possible injection attempts, because all ' are removed prior to attempting an insertion of a record.

Laravel 5 Carbon format datetime

First parse the created_at field as Carbon object.

$createdAt = Carbon::parse($item['created_at']);

Then you can use

$suborder['payment_date'] = $createdAt->format('M d Y');

Can Rails Routing Helpers (i.e. mymodel_path(model)) be Used in Models?

In Rails 3, 4, and 5 you can use:

Rails.application.routes.url_helpers

e.g.

Rails.application.routes.url_helpers.posts_path
Rails.application.routes.url_helpers.posts_url(:host => "example.com")

Python Remove last 3 characters of a string

Removing any and all whitespace:

foo = ''.join(foo.split())

Removing last three characters:

foo = foo[:-3]

Converting to capital letters:

foo = foo.upper()

All of that code in one line:

foo = ''.join(foo.split())[:-3].upper()

Visual Studio 2012 Web Publish doesn't copy files

My problem was in wrong configuration of myproject.csproj file. '_address-step1-stored.cshtml' file did not copy on publish. 'None' changed to 'Content', now it's ok.

Explode string by one or more spaces or tabs

In order to account for full width space such as

full width

you can extend Bens answer to this:

$searchValues = preg_split("@[\s+ ]@u", $searchString);

Sources:

(I don't have enough reputation to post a comment, so I'm wrote this as an answer.)

did you register the component correctly? For recursive components, make sure to provide the "name" option

Wasted almost one hour, didn't find a solution, so I wanted to contribute =)

In my case, I was importing WRONGLY the component.. like below:

import { MyComponent } from './components/MyComponent'

But the CORRECT is (without curly braces):

import MyComponent from './components/MyComponent'

DATEDIFF function in Oracle

We can directly subtract dates to get difference in Days.

    SET SERVEROUTPUT ON ;
    DECLARE
        V_VAR NUMBER;
    BEGIN
         V_VAR:=TO_DATE('2000-01-02', 'YYYY-MM-DD') - TO_DATE('2000-01-01', 'YYYY-MM-DD') ;
         DBMS_OUTPUT.PUT_LINE(V_VAR);
    END;

Laravel - Return json along with http status code

It's better to do it with helper functions rather than Facades. This solution will work well from Laravel 5.7 onwards

//import dependency
use Illuminate\Http\Response;

//snippet
return \response()->json([
   'status' => '403',//sample entry
   'message' => 'ACCOUNT ACTION HAS BEEN DISABLED',//sample message
], Response::HTTP_FORBIDDEN);//Illuminate\Http\Response sets appropriate headers

Cannot create JDBC driver of class ' ' for connect URL 'null' : I do not understand this exception

In my case I solved the problem editing [tomcat]/Catalina/localhost/[mywebapp_name].xml instead of META-INF/context.xml.

How do I change the database name using MySQL?

InnoDB supports RENAME TABLE statement to move table from one database to another. To use it programmatically and rename database with large number of tables, I wrote a couple of procedures to get the job done. You can check it out here - SQL script @Gist

To use it simply call the renameDatabase procedure.

CALL renameDatabase('old_name', 'new_name');

Tested on MariaDB and should work ideally on all RDBMS using InnoDB transactional engine.

MySQL Error #1133 - Can't find any matching row in the user table

I encountered this error using MySQL in a different context (not within phpMyAdmin). GRANT and SET PASSWORD commands failed on a particular existing user, who was listed in the mysql.user table. In my case, it was fixed by running

FLUSH PRIVILEGES;

The documentation for this command says

Reloads the privileges from the grant tables in the mysql database.

The server caches information in memory as a result of GRANT and CREATE USER statements. This memory is not released by the corresponding REVOKE and DROP USER statements, so for a server that executes many instances of the statements that cause caching, there will be an increase in memory use. This cached memory can be freed with FLUSH PRIVILEGES.

Apparently the user table cache had reached an inconsistent state, causing this weird error message. More information is available here.

Select query to remove non-numeric characters

Here is an elegant solution if your server supports the TRANSLATE function (on sql server it's available on sql server 2017+ and also sql azure).

First, it replaces any non numeric characters with a @ character. Then, it removes all @ characters. You may need to add additional characters that you know may be present in the second parameter of the TRANSLATE call.

select REPLACE(TRANSLATE([Col], 'abcdefghijklmnopqrstuvwxyz+()- ,#+', '@@@@@@@@@@@@@@@@@@@@@@@@@@@@@@@@@@'), '@', '')

How to edit HTML input value colour?

You can change the CSS color property using JavaScript in the onclick event handler (in the same way you change the value property):

<input type="text" onclick="this.value=''; this.style.color='#000'" />

Note that it's not the best practice to use inline JavaScript. You'd be better off giving your input an ID, and moving your JavaScript out to a <script> block instead:

document.getElementById("yourInput").onclick = function() {
    this.value = '';
    this.style.color = '#000';
}

Exec : display stdout "live"

I have found it helpful to add a custom exec script to my utilities that do this.

utilities.js

const { exec } = require('child_process')

module.exports.exec = (command) => {
  const process = exec(command)

  process.stdout.on('data', (data) => {
    console.log('stdout: ' + data.toString())
  })

  process.stderr.on('data', (data) => {
    console.log('stderr: ' + data.toString())
  })

  process.on('exit', (code) => {
    console.log('child process exited with code ' + code.toString())
  })
}

app.js

const { exec } = require('./utilities.js')

exec('coffee -cw my_file.coffee')

jQuery find() method not working in AngularJS directive

From the docs on angular.element:

find() - Limited to lookups by tag name

So if you're not using jQuery with Angular, but relying upon its jqlite implementation, you can't do elm.find('#someid').

You do have access to children(), contents(), and data() implementations, so you can usually find a way around it.

How do you check "if not null" with Eloquent?

We can use

Model::whereNotNull('sent_at');

Model::whereRaw('sent_at is not null');

Fatal error: Call to a member function fetch_assoc() on a non-object

I happen to miss spaces in my query and this error comes.

Ex: $sql= "SELECT * FROM";
$sql .= "table1";

Though the example might look simple, when coding complex queries, the probability for this error is high. I was missing space before word "table1".

Default port for SQL Server

If you have access to the server then you can use

select local_tcp_port from sys.dm_exec_connections where local_tcp_port is not null

For full details see port number of SQL Server

Get value of a merged cell of an excel from its cell address in vba

Even if it is really discouraged to use merge cells in Excel (use Center Across Selection for instance if needed), the cell that "contains" the value is the one on the top left (at least, that's a way to express it).

Hence, you can get the value of merged cells in range B4:B11 in several ways:

Range("B4").Value
Range("B4:B11").Cells(1).Value
Range("B4:B11").Cells(1,1).Value

You can also note that all the other cells have no value in them. While debugging, you can see that the value is empty.

Also note that Range("B4:B11").Value won't work (raises an execution error number 13 if you try to Debug.Print it) because it returns an array.

postgresql return 0 if returned value is null

(this answer was added to provide shorter and more generic examples to the question - without including all the case-specific details in the original question).

There are two distinct "problems" here, the first is if a table or subquery has no rows, the second is if there are NULL values in the query.

For all versions I've tested, postgres and mysql will ignore all NULL values when averaging, and it will return NULL if there is nothing to average over. This generally makes sense, as NULL is to be considered "unknown". If you want to override this you can use coalesce (as suggested by Luc M).

$ create table foo (bar int);
CREATE TABLE

$ select avg(bar) from foo;
 avg 
-----

(1 row)

$ select coalesce(avg(bar), 0) from foo;
 coalesce 
----------
        0
(1 row)

$ insert into foo values (3);
INSERT 0 1
$ insert into foo values (9);
INSERT 0 1
$ insert into foo values (NULL);
INSERT 0 1
$ select coalesce(avg(bar), 0) from foo;
      coalesce      
--------------------
 6.0000000000000000
(1 row)

of course, "from foo" can be replaced by "from (... any complicated logic here ...) as foo"

Now, should the NULL row in the table be counted as 0? Then coalesce has to be used inside the avg call.

$ select coalesce(avg(coalesce(bar, 0)), 0) from foo;
      coalesce      
--------------------
 4.0000000000000000
(1 row)

How to use GROUP_CONCAT in a CONCAT in MySQL

IF OBJECT_ID('master..test') is not null Drop table test

CREATE TABLE test (ID INTEGER, NAME VARCHAR (50), VALUE INTEGER );
INSERT INTO test VALUES (1, 'A', 4);
INSERT INTO test VALUES (1, 'A', 5);
INSERT INTO test VALUES (1, 'B', 8);
INSERT INTO test VALUES (2, 'C', 9);

select distinct NAME , LIST = Replace(Replace(Stuff((select ',', +Value from test where name = _a.name for xml path('')), 1,1,''),'<Value>', ''),'</Value>','') from test _a order by 1 desc

My table name is test , and for concatination I use the For XML Path('') syntax. The stuff function inserts a string into another string. It deletes a specified length of characters in the first string at the start position and then inserts the second string into the first string at the start position.

STUFF functions looks like this : STUFF (character_expression , start , length ,character_expression )

character_expression Is an expression of character data. character_expression can be a constant, variable, or column of either character or binary data.

start Is an integer value that specifies the location to start deletion and insertion. If start or length is negative, a null string is returned. If start is longer than the first character_expression, a null string is returned. start can be of type bigint.

length Is an integer that specifies the number of characters to delete. If length is longer than the first character_expression, deletion occurs up to the last character in the last character_expression. length can be of type bigint.

sudo echo "something" >> /etc/privilegedFile doesn't work

The issue is that it's your shell that handles redirection; it's trying to open the file with your permissions not those of the process you're running under sudo.

Use something like this, perhaps:

sudo sh -c "echo 'something' >> /etc/privilegedFile"

When to use static keyword before global variables?

The static keyword is used in C to restrict the visibility of a function or variable to its translation unit. Translation unit is the ultimate input to a C compiler from which an object file is generated.

Check this: Linkage | Translation unit

WCF vs ASP.NET Web API

The new ASP.NET Web API is a continuation of the previous WCF Web API project (although some of the concepts have changed).

WCF was originally created to enable SOAP-based services. For simpler RESTful or RPCish services (think clients like jQuery) ASP.NET Web API should be good choice.

For us, WCF is used for SOAP and Web API for REST. I wish Web API supported SOAP too. We are not using advanced features of WCF. Here is comparison from MSDN:

enter image description here

ASP.net Web API is all about HTTP and REST based GET,POST,PUT,DELETE with well know ASP.net MVC style of programming and JSON returnable; web API is for all the light weight process and pure HTTP based components. For one to go ahead with WCF even for simple or simplest single web service it will bring all the extra baggage. For light weight simple service for ajax or dynamic calls always WebApi just solves the need. This neatly complements or helps in parallel to the ASP.net MVC.

Check out the podcast : Hanselminutes Podcast 264 - This is not your father's WCF - All about the WebAPI with Glenn Block by Scott Hanselman for more information.

In the scenarios listed below you should go for WCF:

If you need to send data on protocols like TCP, MSMQ or MIME
If the consuming client just knows how to consume SOAP messages

WEB API is a framework for developing RESTful/HTTP services.

There are so many clients that do not understand SOAP like Browsers, HTML5, in those cases WEB APIs are a good choice.

HTTP services header specifies how to secure service, how to cache the information, type of the message body and HTTP body can specify any type of content like HTML not just XML as SOAP services.

Counting the number of elements in array

Best practice of getting length is use length filter returns the number of items of a sequence or mapping, or the length of a string. For example: {{ notcount | length }}

But you can calculate count of elements in for loop. For example:

{% set count = 0 %}
{% for nc in notcount %}
    {% set count = count + 1 %}
{% endfor %}

{{ count }}

This solution helps if you want to calculate count of elements by condition, for example you have a property name inside object and you want to calculate count of objects with not empty names:

{% set countNotEmpty = 0 %}
{% for nc in notcount if nc.name %}
    {% set countNotEmpty = countNotEmpty + 1 %}
{% endfor %}

{{ countNotEmpty }}

Useful links:

Style bottom Line in Android

This answer is for those google searchers who want to show dotted bottom border of EditText like here

Create dotted.xml inside drawable folder and paste these

<layer-list xmlns:android="http://schemas.android.com/apk/res/android">
    <item
        android:bottom="1dp"
        android:left="-2dp"
        android:right="-2dp"
        android:top="-2dp">
        <shape android:shape="rectangle">
            <stroke
                android:width="0.5dp"
                android:color="@android:color/black" />    
            <solid android:color="#ffffff" />
            <stroke
                android:width="1dp"
                android:color="#030310"
                android:dashGap="5dp"
                android:dashWidth="5dp" />
            <padding
                android:bottom="5dp"
                android:left="5dp"
                android:right="5dp"
                android:top="5dp" />
        </shape>
    </item>
</layer-list>

Then simply set the android:background attribute to dotted.xml we just created. Your EditText looks like this.

<EditText
    android:id="@+id/editText"
    android:layout_width="match_parent"
    android:layout_height="wrap_content"
    android:text="Some Text"
    android:background="@drawable/dotted" />

Using multiple parameters in URL in express

For what you want I would've used

    app.get('/fruit/:fruitName&:fruitColor', function(request, response) {
       const name = request.params.fruitName 
       const color = request.params.fruitColor 
    });

or better yet

    app.get('/fruit/:fruit', function(request, response) {
       const fruit = request.params.fruit
       console.log(fruit)
    });

where fruit is a object. So in the client app you just call

https://mydomain.dm/fruit/{"name":"My fruit name", "color":"The color of the fruit"}

and as a response you should see:

    //  client side response
    // { name: My fruit name, color:The color of the fruit}

Having links relative to root?

<a href="/fruits/index.html">Back to Fruits List</a>

Laravel Controller Subfolder routing

I am using Laravel 4.2. Here how I do it:
I have a directory structure like this one:
app
--controllers
----admin
------AdminController.php

After I have created the controller I've put in the composer.json the path to the new admin directory:

"autoload": {
"classmap": [
"app/commands",
"app/controllers",
"app/controllers/admin",
"app/models",
"app/database/migrations",
"app/database/seeds",
"app/tests/TestCase.php"
]
},

Next I have run

composer dump-autoload

and then

php artisan dump-autoload

Then in the routes.php I have the controller included like this:

Route::controller('admin', 'AdminController');

And everything works fine.

Auto increment in phpmyadmin

There are possible steps to enable auto increment for a column. I guess the phpMyAdmin version is 3.5.5 but not sure.

Click on Table > Structure tab > Under Action Click Primary (set as primary), click on Change on the pop-up window, scroll left and check A_I. Also make sure you have selected None for Default enter image description here

How to make Bootstrap carousel slider use mobile left/right swipe

If you don't want to use jQuery mobile as like me. You can use Hammer.js

It's mostly like jQuery Mobile without unnecessary code.

$(document).ready(function() {
  Hammer(myCarousel).on("swipeleft", function(){
    $(this).carousel('next');
  });
  Hammer(myCarousel).on("swiperight", function(){
    $(this).carousel('prev');
  });
});

error NG6002: Appears in the NgModule.imports of AppModule, but could not be resolved to an NgModule class

Your module is not yet loaded by the Angular Server in node ng serve, so restart your server so the server loads the module that you just added in @NgModule app.module.ts

Can't connect to local MySQL server through socket '/tmp/mysql.sock' (2)

In your mysql config file, which is present in /etc/my.cnf make the below changes and then restart mysqld dameon process

[client]
socket=/var/lib/mysql/mysql.sock

As well check this related thread

Can't connect to local MySQL server through socket '/tmp/mysql.sock

Difference between multitasking, multithreading and multiprocessing?

Multiprogramming-More than on job in main memory.

Muntitasking - More than one program run simultaneously. that is more than one program in CPU.

http to https through .htaccess

The below code, when added to the .htaccess file, will automatically redirect any traffic destined for http: to https:

<IfModule mod_rewrite.c>
    RewriteEngine On
    RewriteCond %{HTTPS} off
    RewriteRule (.*) https://%{HTTP_HOST}%{REQUEST_URI} [R,L]
</IfModule>

If your project is in Laravel add the two lines

RewriteCond %{HTTPS} off
RewriteRule (.*) https://%{HTTP_HOST}%{REQUEST_URI} [R,L]

just below RewriteEngine On. Finally your .htaccess file will look like the following.

<IfModule mod_rewrite.c>
    <IfModule mod_negotiation.c>
        Options -MultiViews -Indexes
    </IfModule>

    RewriteEngine On

    RewriteCond %{HTTPS} off
    RewriteRule (.*) https://%{HTTP_HOST}%{REQUEST_URI} [R,L]

    # Handle Authorization Header
    RewriteCond %{HTTP:Authorization} .
    RewriteRule .* - [E=HTTP_AUTHORIZATION:%{HTTP:Authorization}]

    # Redirect Trailing Slashes If Not A Folder...
    RewriteCond %{REQUEST_FILENAME} !-d
    RewriteCond %{REQUEST_URI} (.+)/$
    RewriteRule ^ %1 [L,R=301]

    # Handle Front Controller...
    RewriteCond %{REQUEST_FILENAME} !-d
    RewriteCond %{REQUEST_FILENAME} !-f
    RewriteRule ^ index.php [L]
</IfModule>

Visite here to more information

Fixed position but relative to container

Check this:

<html xmlns="http://www.w3.org/1999/xhtml">
    <head>
        <title></title>
    </head>
    <body style="width: 1000px !important;margin-left: auto;margin-right: auto">
        <div style="width: 100px; height: 100px; background-color: #ccc; position:fixed;">
        </div>
        <div id="1" style="width: 100%; height: 600px; background-color: #800000">
        </div>
        <div id="2" style="width: 100%; height: 600px; background-color: #100000">
        </div>
        <div id="3" style="width: 100%; height: 600px; background-color: #400000">
        </div>
    </body>
</html>

C++: Rounding up to the nearest multiple of a number

This works for positive numbers, not sure about negative. It only uses integer math.

int roundUp(int numToRound, int multiple)
{
    if (multiple == 0)
        return numToRound;

    int remainder = numToRound % multiple;
    if (remainder == 0)
        return numToRound;

    return numToRound + multiple - remainder;
}

Edit: Here's a version that works with negative numbers, if by "up" you mean a result that's always >= the input.

int roundUp(int numToRound, int multiple)
{
    if (multiple == 0)
        return numToRound;

    int remainder = abs(numToRound) % multiple;
    if (remainder == 0)
        return numToRound;

    if (numToRound < 0)
        return -(abs(numToRound) - remainder);
    else
        return numToRound + multiple - remainder;
}

Writing files in Node.js

The answers provided are dated and a newer way to do this is:

const fsPromises = require('fs').promises
await fsPromises.writeFile('/path/to/file.txt', 'data to write')

see documents here for more info

Can I write or modify data on an RFID tag?

I did some development with Mifare Classic (ISO 14443A) cards about 7-8 years ago. You can read and write to all sectors of the card, IIRC the only data you can't change is the serial number. Back then we used a proprietary library from Philips Semiconductors. The command interface to the card was quite alike the ISO 7816-4 (used with standard Smart Cards).

I'd recomment that you look at the OpenPCD platform if you are into development.

This is also of interest regarding the cryptographic functions in some RFID cards.

convert strtotime to date time format in php

$unixtime = 1307595105;
echo $time = date("m/d/Y h:i:s A T",$unixtime);

Where

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

sed command with -i option failing on Mac, but works on Linux

If you use the -i option you need to provide an extension for your backups.

If you have:

File1.txt
File2.cfg

The command (note the lack of space between -i and '' and the -e to make it work on new versions of Mac and on GNU):

sed -i'.original' -e 's/old_link/new_link/g' *

Create 2 backup files like:

File1.txt.original
File2.cfg.original

There is no portable way to avoid making backup files because it is impossible to find a mix of sed commands that works on all cases:

sed -i -e ... - does not work on OS X as it creates -e backups
sed -i'' -e ... - does not work on OS X 10.6 but works on 10.9+
sed -i '' -e ... - not working on GNU

Note Given that there isn't a sed command working on all platforms, you can try to use another command to achieve the same result.

E.g., perl -i -pe's/old_link/new_link/g' *

Implement a loading indicator for a jQuery AJAX call

I solved the same problem following this example:

This example uses the jQuery JavaScript library.

First, create an Ajax icon using the AjaxLoad site.
Then add the following to your HTML :

<img src="/images/loading.gif" id="loading-indicator" style="display:none" />

And the following to your CSS file:

#loading-indicator {
  position: absolute;
  left: 10px;
  top: 10px;
}

Lastly, you need to hook into the Ajax events that jQuery provides; one event handler for when the Ajax request begins, and one for when it ends:

$(document).ajaxSend(function(event, request, settings) {
    $('#loading-indicator').show();
});

$(document).ajaxComplete(function(event, request, settings) {
    $('#loading-indicator').hide();
});

This solution is from the following link. How to display an animated icon during Ajax request processing

Pip Install not installing into correct directory?

This is what worked for me on Windows. The cause being multiple python installations

update path with correct python
uninstall pip using python -m pip uninstall pip setuptools
restart windows didn't work until a restart

HTML input fields does not get focus when clicked

I had this problem too. I used the disableSelection() method of jQuery UI on a parent DIV which contained my input fields. In Chrome the input fields were not affected but in Firefox the inputs (and textareas as well) did not get focused on clicking. The strange thing here was, that the click event on these inputs worked.

The solution was to remove the disableSelection() method for the parent DIV.

PHP class not found but it's included

As a more systematic and structured solution you could define folders where your classes are stored and create an autoloader (__autoload()) which will search the class files in defined places:

require_once("../settings.php");
define('DIR_CLASSES', '/path/to/the/classes/folder/'); // this can be inside your settings.php

$user = new User();
$user->createUser($_POST["username"], $_POST["email"], $_POST["password"]);

function __autoload($classname) { 
    if(file_exists(DIR_CLASSES . 'class' . $classname . '.php')) {
        include_once(DIR_CLASSES . 'class' . $classname . '.php'); // looking for the class in the project's classes folder
    } else {
        include_once($classname . '.php'); // looking for the class in include_path
    }
}

Postgresql: error "must be owner of relation" when changing a owner object

This solved my problem : Sample alter table statement to change the ownership.

ALTER TABLE databasechangelog OWNER TO arwin_ash;
ALTER TABLE databasechangeloglock OWNER TO arwin_ash;

swift UITableView set rowHeight

Problem Cause:
The problem is that the cell has not been created yet. TableView first calculates the height for row and then populates the data for each row, so the rows array has not been created when heightForRow method gets called. So your app is trying to access a memory location which it does not have the permission to and therefor you get the EXC_BAD_ACCESS message.

How to achieve self sizing TableViewCell in UITableView:
Just set proper constraints for your views contained in TableViewCell's view in StoryBoard. Remember you shouldn't set height constraints to TableViewCell's root view, its height should be properly computable by the height of its subviews -- This is like what you do to set proper constraints for UIScrollView. This way your cells will get different heights according to their subviews. No additional action needed

Converting String to Int using try/except in Python

You can do :

try : 
   string_integer = int(string)
except ValueError  :
   print("This string doesn't contain an integer")

Sorted array list in Java

It might be a bit too heavyweight for you, but GlazedLists has a SortedList that is perfect to use as the model of a table or JList

CSS - how to make image container width fixed and height auto stretched

No, you can't make the img stretch to fit the div and simultaneously achieve the inverse. You would have an infinite resizing loop. However, you could take some notes from other answers and implement some min and max dimensions but that wasn't the question.

You need to decide if your image will scale to fit its parent or if you want the div to expand to fit its child img.

Using this block tells me you want the image size to be variable so the parent div is the width an image scales to. height: auto is going to keep your image aspect ratio in tact. if you want to stretch the height it needs to be 100% like this fiddle.

img {
    width: 100%;
    height: auto;
}

http://jsfiddle.net/D8uUd/1/

What to do with branch after merge

I prefer RENAME rather than DELETE

All my branches are named in the form of

Fix/fix-<somedescription> or
Ftr/ftr-<somedescription> or
etc.

Using Tower as my git front end, it neatly organizes all the Ftr/, Fix/, Test/ etc. into folders.
Once I am done with a branch, I rename them to Done/...-<description>.

That way they are still there (which can be handy to provide history) and I can always go back knowing what it was (feature, fix, test, etc.)

Using Excel VBA to export data to MS Access table

is it possible to export without looping through all records

For a range in Excel with a large number of rows you may see some performance improvement if you create an Access.Application object in Excel and then use it to import the Excel data into Access. The code below is in a VBA module in the same Excel document that contains the following test data

Option Explicit

Sub AccImport()
    Dim acc As New Access.Application
    acc.OpenCurrentDatabase "C:\Users\Public\Database1.accdb"
    acc.DoCmd.TransferSpreadsheet _
            TransferType:=acImport, _
            SpreadSheetType:=acSpreadsheetTypeExcel12Xml, _
            TableName:="tblExcelImport", _
            Filename:=Application.ActiveWorkbook.FullName, _
            HasFieldNames:=True, _
            Range:="Folio_Data_original$A1:B10"
    acc.CloseCurrentDatabase
    acc.Quit
    Set acc = Nothing
End Sub

How to Correctly handle Weak Self in Swift Blocks with Arguments

As of swift 4.2 we can do:

_ = { [weak self] value in
    guard let self = self else { return }
    print(self) // will never be nil
}()

Converting of Uri to String

String to Uri

Uri myUri = Uri.parse("https://www.google.com");

Uri to String

Uri uri;
String stringUri = uri.toString();

Search and get a line in Python

items=re.findall("token.*$",s,re.MULTILINE)
>>> for x in items:

you can also get the line if there are other characters before token

items=re.findall("^.*token.*$",s,re.MULTILINE)

The above works like grep token on unix and keyword 'in' or .contains in python and C#

s='''
qwertyuiop
asdfghjkl

zxcvbnm
token qwerty

asdfghjklñ
'''

http://pythex.org/ matches the following 2 lines

....
....
token qwerty

How to set fake GPS location on IOS real device

Of course ios7 prohibits creating fake locations on real device.
For testing purpose there are two approches:
1) while device is connected to xcode, use the simulator and let it play a gpx track.

2) for real world testing, not connected to simu, one possibility is that your app, has a special modus built in, where you set it to "playback" mode. In that mode the app has to create the locations itself, using a timer of 1s, and creating a new CLLocation object.

3) A third possibility is described here: https://blackpixel.com/writing/2013/05/simulating-locations-with-xcode.html

How do I get the last word in each line with bash

Another way of doing this in plain bash is making use of the rev command like this:

cat file | rev | cut -d" " -f1 | rev | tr -d "." | tr "\n" ","

Basically, you reverse the lines of the file, then split them with cut using space as the delimiter, take the first field that cut produces and then you reverse the token again, use tr -d to delete unwanted chars and tr again to replace newline chars with ,

Also, you can avoid the first cat by doing:

rev < file | cut -d" " -f1 | rev | tr -d "." | tr "\n" ","

disable viewport zooming iOS 10+ safari?

In the current version of safari this is not working anymore. You have to define the second parameter as non-passive by passing {passiv:false}

 document.addEventListener('touchmove', function(e) {
 e.preventDefault();
}, { passive: false });

Default interface methods are only supported starting with Android N

apply plugin: 'com.android.application'
apply plugin: 'kotlin-android'
apply plugin: 'kotlin-android-extensions'


android {
compileSdkVersion 30
buildToolsVersion "30.0.0"

compileOptions {
    sourceCompatibility JavaVersion.VERSION_1_8
    targetCompatibility JavaVersion.VERSION_1_8
}

defaultConfig {
    applicationId "com.example.architecture"
    minSdkVersion 16
    targetSdkVersion 30
    versionCode 1
    versionName "1.0"

    testInstrumentationRunner "androidx.test.runner.AndroidJUnitRunner"
}
 buildTypes {
    release {
        minifyEnabled false
        proguardFiles getDefaultProguardFile('proguard-android-optimize.txt'), 'proguard-rules.pro'
    }
   }
}
dependencies {

implementation 'androidx.room:room-runtime:2.2.5'
implementation 'androidx.lifecycle:lifecycle-extensions:2.2.0'
annotationProcessor 'androidx.room:room-compiler:2.2.5'
def lifecycle_version = "2.2.0"
def arch_version = "2.1.0"

implementation fileTree(dir: "libs", include: ["*.jar"])
implementation "org.jetbrains.kotlin:kotlin-stdlib:$kotlin_version"
implementation 'androidx.core:core-ktx:1.3.0'
implementation 'androidx.appcompat:appcompat:1.1.0'
implementation 'androidx.constraintlayout:constraintlayout:1.1.3'
testImplementation 'junit:junit:4.12'
androidTestImplementation 'androidx.test.ext:junit:1.1.1'
androidTestImplementation 'androidx.test.espresso:espresso-core:3.2.0'
implementation "androidx.lifecycle:lifecycle-viewmodel-savedstate:$lifecycle_version"
implementation "androidx.lifecycle:lifecycle-common-java8:$lifecycle_version"
implementation "androidx.lifecycle:lifecycle-service:$lifecycle_version"
implementation "androidx.lifecycle:lifecycle-process:$lifecycle_version"
implementation "androidx.cardview:cardview:1.0.0"
}

Add the configuration in your app module's build.gradle

android {
    ...
    compileOptions {
        sourceCompatibility JavaVersion.VERSION_1_8
        targetCompatibility JavaVersion.VERSION_1_8
    }
}

Java, Simplified check if int array contains int

You could simply use ArrayUtils.contains from Apache Commons Lang library.

public boolean contains(final int[] array, final int key) {     
    return ArrayUtils.contains(array, key);
}

How do you stash an untracked file?

I encountered a similar problem while using Sourcetree with newly created files (they wouldnt be included in the stash either).

When I first chose 'stage all' and then stash the newly added components where tracked and therefore included in the stash.

Disabling Warnings generated via _CRT_SECURE_NO_DEPRECATE

Combination of @[macbirdie] and @[Adrian Borchardt] answer. Which proves to be very useful in production environment (not messing up previously existing warning, especially during cross-platform compile)

#if (_MSC_VER >= 1400)         // Check MSC version
#pragma warning(push)
#pragma warning(disable: 4996) // Disable deprecation
#endif 
//...                          // ...
strcat(base, cat);             // Sample depreciated code
//...                          // ...
#if (_MSC_VER >= 1400)         // Check MSC version
#pragma warning(pop)           // Renable previous depreciations
#endif

Boolean.parseBoolean("1") = false...?

Java is strongly typed. 0 and 1 are numbers, which is a different type than a boolean. A number will never be equal to a boolean.

How to navigate back to the last cursor position in Visual Studio Code?

This will be different for each OS, based on the information at https://code.visualstudio.com/docs/customization/keybindings

Go Back: workbench.action.navigateBack Go Forward: workbench.action.navigateForward

Linux Go Back: Ctrl+Alt+-
Go Forward: Ctrl+Shift+-

OSX ^- / ^?-

Windows Alt+ ? / ?

Fastest way to ping a network range and return responsive hosts?

BSD's

for i in $(seq 1 254); do (ping -c1 -W5 192.168.1.$i >/dev/null && echo "192.168.1.$i" &) ;done

How do I undo 'git add' before commit?

To remove new files from the staging area (and only in case of a new file), as suggested above:

git rm --cached FILE

Use rm --cached only for new files accidentally added.

Python: Select subset from list based on index set

I see 2 options.

Using numpy:

property_a = numpy.array([545., 656., 5.4, 33.])
property_b = numpy.array([ 1.2,  1.3, 2.3, 0.3])
good_objects = [True, False, False, True]
good_indices = [0, 3]
property_asel = property_a[good_objects]
property_bsel = property_b[good_indices]

Using a list comprehension and zip it:

property_a = [545., 656., 5.4, 33.]
property_b = [ 1.2,  1.3, 2.3, 0.3]
good_objects = [True, False, False, True]
good_indices = [0, 3]
property_asel = [x for x, y in zip(property_a, good_objects) if y]
property_bsel = [property_b[i] for i in good_indices]

Get day of week using NSDate

There is an easier way. Just pass your string date to the following function, it will give you the day name :)

func getDayNameBy(stringDate: String) -> String
    {
        let df  = NSDateFormatter()
        df.dateFormat = "YYYY-MM-dd"
        let date = df.dateFromString(stringDate)!
        df.dateFormat = "EEEE"
        return df.stringFromDate(date);
    }

Java replace issues with ' (apostrophe/single quote) and \ (backslash) together

If you want to use it in JavaScript then you can use

str.replace("SP","\\SP");

But in Java

str.replaceAll("SP","\\SP");

will work perfectly.

SP: special character

Otherwise you can use Apache's EscapeUtil. It will solve your problem.

Update row values where certain condition is met in pandas

You can do the same with .ix, like this:

In [1]: df = pd.DataFrame(np.random.randn(5,4), columns=list('abcd'))

In [2]: df
Out[2]: 
          a         b         c         d
0 -0.323772  0.839542  0.173414 -1.341793
1 -1.001287  0.676910  0.465536  0.229544
2  0.963484 -0.905302 -0.435821  1.934512
3  0.266113 -0.034305 -0.110272 -0.720599
4 -0.522134 -0.913792  1.862832  0.314315

In [3]: df.ix[df.a>0, ['b','c']] = 0

In [4]: df
Out[4]: 
          a         b         c         d
0 -0.323772  0.839542  0.173414 -1.341793
1 -1.001287  0.676910  0.465536  0.229544
2  0.963484  0.000000  0.000000  1.934512
3  0.266113  0.000000  0.000000 -0.720599
4 -0.522134 -0.913792  1.862832  0.314315

EDIT

After the extra information, the following will return all columns - where some condition is met - with halved values:

>> condition = df.a > 0
>> df[condition][[i for i in df.columns.values if i not in ['a']]].apply(lambda x: x/2)

I hope this helps!

Installed Ruby 1.9.3 with RVM but command line doesn't show ruby -v

Open Terminal.
Go to Edit -> Profile Preferences.
Select the Title & command Tab in the window opened.
Mark the checkbox Run command as login shell.
close the window and restart the Terminal.

Check this Official Link enter image description here

How to upload images into MySQL database using PHP code

Just few more details:

Add mysql field

`image` blob

Get data from image

$image = addslashes(file_get_contents($_FILES['image']['tmp_name']));

Insert image data into db

$sql = "INSERT INTO `product_images` (`id`, `image`) VALUES ('1', '{$image}')";

Show image to the web

<img src="data:image/png;base64,'.base64_encode($row['image']).'">

Which version of CodeIgniter am I currently using?

You should try :

<?php
echo CI_VERSION;
?>

Or check the file system/core/CodeIgniter.php

Selenium WebDriver.get(url) does not open the URL

I was having the save issue when trying with Chrome. I finally placed my chromedrivers.exe in the same location as my project. This fixed it for me.

How to connect Robomongo to MongoDB

Currently, Robomongo 0.8.x doesn't work with MongoDB 3.0:

For now, don't use Robomongo. For me, the best solution is to use MongoChef.

How to reset Jenkins security settings from the command line?

Easy way out of this is to use the admin psw to login with your admin user:

Change to root user: sudo su -
Copy the password: xclip -sel clip < /var/lib/jenkins/secrets/initialAdminPassword
Login with admin and press ctrl + v on password input box.

Install xclip if you don't have it:

$ sudo apt-get install xclip

jQuery Validate Plugin - How to create a simple custom rule?

You can create a simple rule by doing something like this:

jQuery.validator.addMethod("greaterThanZero", function(value, element) {
    return this.optional(element) || (parseFloat(value) > 0);
}, "* Amount must be greater than zero");

And then applying this like so:

$('validatorElement').validate({
    rules : {
        amount : { greaterThanZero : true }
    }
});

Just change the contents of the 'addMethod' to validate your checkboxes.

Best dynamic JavaScript/JQuery Grid

you can try http://datatables.net/

DataTables is a plug-in for the jQuery Javascript library. It is a highly flexible tool, based upon the foundations of progressive enhancement, which will add advanced interaction controls to any HTML table. Key features:

Variable length pagination
On-the-fly filtering
Multi-column sorting with data type detection
Smart handling of column widths
Display data from almost any data source
DOM, Javascript array, Ajax file and server-side processing (PHP, C#, Perl, Ruby, AIR, Gears etc)
Scrolling options for table viewport
Fully internationalisable
jQuery UI ThemeRoller support
Rock solid - backed by a suite of 2600+ unit tests
Wide variety of plug-ins inc. TableTools, FixedColumns, KeyTable and more
It's free!
State saving
Hidden columns
Dynamic creation of tables
Ajax auto loading of data
Custom DOM positioning
Single column filtering
Alternative pagination types
Non-destructive DOM interaction
Sorting column(s) highlighting
Advanced data source options
Extensive plug-in support
Sorting, type detection, API functions, pagination and filtering
Fully themeable by CSS
Solid documentation
110+ pre-built examples
Full support for Adobe AIR

How to copy to clipboard in Vim?

Use the register "+ to copy to the system clipboard (i.e. "+y instead of y).

Likewise you can paste from "+ to get text from the system clipboard (i.e. "+p instead of p).

Trimming text strings in SQL Server 2008

SQL Server does not have a TRIM function, but rather it has two. One each for specifically trimming spaces from the "front" of a string (LTRIM) and one for trimming spaces from the "end" of a string (RTRIM).

Something like the following will update every record in your table, trimming all extraneous space (either at the front or the end) of a varchar/nvarchar field:

UPDATE 
   [YourTableName]
SET
   [YourFieldName] = LTRIM(RTRIM([YourFieldName]))

(Strangely, SSIS (Sql Server Integration Services) does have a single TRIM function!)

Combining border-top,border-right,border-left,border-bottom in CSS

I can relate to the problem, there should be a shorthand like...

border: 1px solid red top bottom left;

Of course that doesn't work! Kobi's answer gave me an idea. Let's say you want to do top, bottom and left, but not right. Instead of doing border-top: border-left: border-bottom: (three statements) you could do two like this, the zero cancels out the right side.

border: 1px dashed yellow;
border-width:1px 0 1px 1px;

Two statements instead of three, small improvement :-D

Remove duplicate dict in list in Python

how to reset <input type = "file">

SOLUTION

The following code worked for me with jQuery. It works in every browser and allows to preserve events and custom properties.

var $el = $('#uploadCaptureInputFile');
$el.wrap('<form>').closest('form').get(0).reset();
$el.unwrap();

DEMO

See this jsFiddle for code and demonstration.

LINKS

See How to reset file input with JavaScript for more information.

Determining 32 vs 64 bit in C++

I'm adding this answer as a use case and complete example for the runtime-check described in another answer.

This is the approach I've been taking for conveying to the end-user whether the program was compiled as 64-bit or 32-bit (or other, for that matter):

version.h

#ifndef MY_VERSION
#define MY_VERSION

#include <string>

const std::string version = "0.09";
const std::string arch = (std::to_string(sizeof(void*) * 8) + "-bit");

#endif

test.cc

#include <iostream>
#include "version.h"

int main()
{
    std::cerr << "My App v" << version << " [" << arch << "]" << std::endl;
}

Compile and Test

g++ -g test.cc
./a.out
My App v0.09 [64-bit]

How to get ELMAH to work with ASP.NET MVC [HandleError] attribute?

This is exactly what I needed for my MVC site configuration!

I added a little modification to the OnException method to handle multiple HandleErrorAttribute instances, as suggested by Atif Aziz:

bear in mind that you may have to take care that if multiple HandleErrorAttribute instances are in effect then duplicate logging does not occur.

I simply check context.ExceptionHandled before invoking the base class, just to know if someone else handled the exception before current handler.
It works for me and I post the code in case someone else needs it and to ask if anyone knows if I overlooked anything.

Hope it is useful:

public override void OnException(ExceptionContext context)
{
    bool exceptionHandledByPreviousHandler = context.ExceptionHandled;

    base.OnException(context);

    Exception e = context.Exception;
    if (exceptionHandledByPreviousHandler
        || !context.ExceptionHandled  // if unhandled, will be logged anyhow
        || RaiseErrorSignal(e)        // prefer signaling, if possible
        || IsFiltered(context))       // filtered?
        return;

    LogException(e);
}

Get docker container id from container name

In Linux:

sudo docker ps -aqf "name=containername"

Or in OS X, Windows:

docker ps -aqf "name=containername"

where containername is your container name.

To avoid getting false positives, as @llia Sidorenko notes, you can use regex anchors like so:

docker ps -aqf "name=^containername$"

explanation:

-q for quiet. output only the ID
-a for all. works even if your container is not running
-f for filter.
^ container name must start with this string
$ container name must end with this string

The program can't start because api-ms-win-crt-runtime-l1-1-0.dll is missing while starting Apache server on my computer

I was facing the same issue. After many tries below solution worked for me.

Before installing VC++ install your windows updates. 1. Go to Start - Control Panel - Windows Update 2. Check for the updates. 3. Install all updates. 4. Restart your system.

After that you can follow the below steps.

@ABHI KUMAR

Download the Visual C++ Redistributable 2015

Visual C++ Redistributable for Visual Studio 2015 (64-bit)

Visual C++ Redistributable for Visual Studio 2015 (32-bit)

(Reinstal if already installed) then restart your computer or use windows updates for download auto.

For link download https://www.microsoft.com/de-de/download/details.aspx?id=48145.

How do you determine what technology a website is built on?

I use 1 plug in for Firefox that gives me the IP and country for the hosting website and it's Web Server name called Domain Details, and for javascript framework I use WTFramework

I still need to wonder what script it was written on, but it is a start :)

Hope it helps.

P.S. the output will be something like this:

alt text http://img88.imageshack.us/img88/2505/200812282328ha0.png

Android error while retrieving information from server 'RPC:s-5:AEC-0' in Google Play?

There's no need to remove an account: I switched Google Play to a second Google account, installed an update, and switched back to my original account.

Though apparently, it's sufficient to just switch to a second Google Account, and switch back to the original account, no need to install an update.

C# Iterate through Class properties

You could possibly use Reflection to do this. As far as I understand it, you could enumerate the properties of your class and set the values. You would have to try this out and make sure you understand the order of the properties though. Refer to this MSDN Documentation for more information on this approach.

For a hint, you could possibly do something like:

Record record = new Record();

PropertyInfo[] properties = typeof(Record).GetProperties();
foreach (PropertyInfo property in properties)
{
    property.SetValue(record, value);
}

Where value is the value you're wanting to write in (so from your resultItems array).

Could not load file or assembly CrystalDecisions.ReportAppServer.ClientDoc

Regarding the 64-bit system wanting 32-bit support. I don't find it so bizarre:

Although deployed to a 64-bit system, this doesn't mean all the referenced assemblies are necessarily 64-bit Crystal Reports assemblies. Further to that, the Crystal Reports assemblies are largely just wrappers to a collection of legacy DLLs upon which they are based. Many 32-bit DLLs are required by the primarily referenced assembly. The error message "can not load the assembly" involves these DLLs as well. To see visually what those are, go to www.dependencywalker.com and run 'Depends' on the assembly in question, directly on that IIS server.

How do I get the max and min values from a set of numbers entered?

This is what I did and it works try and play around with it. It calculates total,avarage,minimum and maximum.

public static void main(String[] args) {
   int[] score= {56,90,89,99,59,67};
   double avg;
   int sum=0;
   int maxValue=0;
   int minValue=100;

   for(int i=0;i<6;i++){
       sum=sum+score[i];
   if(score[i]<minValue){
    minValue=score[i];
   }
   if(score[i]>maxValue){
    maxValue=score[i];
   }
   }
   avg=sum/6.0;
System.out.print("Max: "+maxValue+"," +" Min: "+minValue+","+" Avarage: "+avg+","+" Sum: "+sum);}

 }

Reading int values from SqlDataReader

Use the GetInt method.

reader.GetInt32(3);

Show Console in Windows Application?

In wind32, console-mode applications are a completely different beast from the usual message-queue-receiving applications. They are declared and compile differently. You might create an application which has both a console part and normal window and hide one or the other. But suspect you will find the whole thing a bit more work than you thought.

How to pass an array to a function in VBA?

This seems unnecessary, but VBA is a strange place. If you declare an array variable, then set it using Array() then pass the variable into your function, VBA will be happy.

Sub test()
    Dim fString As String
    Dim arr() As Variant
    arr = Array("foo", "bar")
    fString = processArr(arr)
End Sub

Also your function processArr() could be written as:

Function processArr(arr() As Variant) As String
    processArr = Replace(Join(arr()), " ", "")
End Function

If you are into the whole brevity thing.

How to get base url in CodeIgniter 2.*

To use base_url() (shorthand), you have to load the URL Helper first

$this->load->helper('url');

Or you can autoload it by changing application/config/autoload.php

Or just use

$this->config->base_url();

Same applies to site_url().

Also I can see you are missing echo (though its not your current problem), use the code below to solve the problem

<link rel="stylesheet" href="<?php echo base_url(); ?>css/default.css" type="text/css" />

getting only name of the class Class.getName()

You can use following simple technique for print log with class name.

private String TAG = MainActivity.class.getSimpleName();

Suppose we have to check coming variable value in method then we can use log like bellow :

private void printVariable(){
Log.e(TAG, "printVariable: ");
}

Importance of this line is that, we can check method name along with class name. To write this type of log.

write :- loge and Enter.

will print on console

E/MainActivity: printVariable:

Fluid or fixed grid system, in responsive design, based on Twitter Bootstrap

When you decide between fixed width and fluid width you need to think in terms of your ENTIRE page. Generally, you want to pick one or the other, but not both. The examples you listed in your question are, in-fact, in the same fixed-width page. In other words, the Scaffolding page is using a fixed-width layout. The fixed grid and fluid grid on the Scaffolding page are not meant to be examples, but rather the documentation for implementing fixed and fluid width layouts.

The proper fixed width example is here. The proper fluid width example is here.

When observing the fixed width example, you should not see the content changing sizes when your browser is greater than 960px wide. This is the maximum (fixed) width of the page. Media queries in a fixed-width design will designate the minimum widths for particular styles. You will see this in action when you shrink your browser window and see the layout snap to a different size.

Conversely, the fluid-width layout will always stretch to fit your browser window, no matter how wide it gets. The media queries indicate when the styles change, but the width of containers are always a percentage of your browser window (rather than a fixed number of pixels).

The 'responsive' media queries are all ready to go. You just need to decide if you want to use a fixed width or fluid width layout for your page.

Previously, in bootstrap 2, you had to use row-fluid inside a fluid container and row inside a fixed container. With the introduction of bootstrap 3, row-fluid was removed, do no longer use it.

EDIT: As per the comments, some jsFiddles for:

These fiddles are completely Bootstrap-free, based on pure CSS media queries, which makes them a good starting point, for anyone willing to craft similar solution without using Twitter Bootstrap.

How can I do time/hours arithmetic in Google Spreadsheet?

I had a similar issue and i just fixed it for now

format each of the cell to time
format the total cell (sum of all the time) to Duration

How to make a phone call using intent in Android?

// Java
String mobileNumber = "99XXXXXXXX";
Intent intent = new Intent();
intent.setAction(Intent.ACTION_DIAL); // Action for what intent called for
intent.setData(Uri.parse("tel: " + mobileNumber)); // Data with intent respective action on intent
startActivity(intent);

// Kotlin
val mobileNumber = "99XXXXXXXX"
val intent = Intent()
intent.action = Intent.ACTION_DIAL // Action for what intent called for
intent.data = Uri.parse("tel: $mobileNumber") // Data with intent respective action on intent
startActivity(intent)

What is Dispatcher Servlet in Spring?

We can say like DispatcherServlet taking care of everything in Spring MVC.

At web container start up:

DispatcherServlet will be loaded and initialized by calling init() method
init() of DispatcherServlet will try to identify the Spring Configuration Document with naming conventions like "servlet_name-servlet.xml" then all beans can be identified.

Example:

public class DispatcherServlet extends HttpServlet {

    ApplicationContext ctx = null;

    public void init(ServletConfig cfg){
        // 1. try to get the spring configuration document with default naming conventions
        String xml = "servlet_name" + "-servlet.xml";

        //if it was found then creates the ApplicationContext object
        ctx = new XmlWebApplicationContext(xml);
    }
    ...
}

So, in generally DispatcherServlet capture request URI and hand over to HandlerMapping. HandlerMapping search mapping bean with method of controller, where controller returning logical name(view). Then this logical name is send to DispatcherServlet by HandlerMapping. Then DispatcherServlet tell ViewResolver to give full location of view by appending prefix and suffix, then DispatcherServlet give view to the client.

sqlite copy data from one table to another

If you have data already present in both the tables and you want to update a table column values based on some condition then use this

UPDATE Table1 set Name=(select t2.Name from Table2 t2 where t2.id=Table1.id)

How to set xampp open localhost:8080 instead of just localhost

you can get loccalhost page by writing localhost/xampp or by writing http://127.0.0.1 you will get the local host page. After starting the apache serve that can be from wamp, xamp or lamp.

Eclipse - "Workspace in use or cannot be created, chose a different one."

I've seen 3 other fixes so far:

in .metadata/, rm .lock file
if 1) doesn't work, try end process javaw.exe etc. to exit the IDE
if 1)&2) doesn't work, try rm .log file in .metadata/, and double check .plugin/.
This always worked for me: relocate .metadata/, open and close eclipse, then overwrite .metadata back

The solution boils down to clean up the .metadata folder with correct contents

How do I iterate through table rows and cells in JavaScript?

Using a single for loop:

var table = document.getElementById('tableID');  
var count = table.rows.length;  
for(var i=0; i<count; i++) {    
    console.log(table.rows[i]);    
}

How do I use dataReceived event of the SerialPort Port Object in C#?

Might very well be the Console.ReadLine blocking your callback's Console.Writeline, in fact. The sample on MSDN looks ALMOST identical, except they use ReadKey (which doesn't lock the console).

Domain Account keeping locking out with correct password every few minutes

Try this solution from http://social.technet.microsoft.com/Forums/en/w7itprosecurity/thread/e1ef04fa-6aea-47fe-9392-45929239bd68

Microsoft Support found the problem for us. Our domain accounts were locking when a Windows 7 computer was started. The Windows 7 computer had a hidden old password from that domain account. There are passwords that can be stored in the SYSTEM context that can't be seen in the normal Credential Manager view.

Download PsExec.exe from http://technet.microsoft.com/en-us/sysinternals/bb897553.aspx and copy it to C:\Windows\System32.

From a command prompt run: psexec -i -s -d cmd.exe

From the new DOS window run: rundll32 keymgr.dll,KRShowKeyMgr

Remove any items that appear in the list of Stored User Names and Passwords. Restart the computer.

How do I delete a local repository in git?

To piggyback on rkj's answer, to avoid endless prompts (and force the command recursively), enter the following into the command line, within the project folder:

$ rm -rf .git

Or to delete .gitignore and .gitmodules if any (via @aragaer):

$ rm -rf .git*

Then from the same ex-repository folder, to see if hidden folder .git is still there:

$ ls -lah

If it's not, then congratulations, you've deleted your local git repo, but not a remote one if you had it. You can delete GitHub repo on their site (github.com).

To view hidden folders in Finder (Mac OS X) execute these two commands in your terminal window:

defaults write com.apple.finder AppleShowAllFiles TRUE
killall Finder

Source: http://lifehacker.com/188892/show-hidden-files-in-finder.

What is CMake equivalent of 'configure --prefix=DIR && make all install '?

The way I build CMake projects cross platform is the following:

/project-root> mkdir build
/project-root> cd build
/project-root/build> cmake -G "<generator>" -DCMAKE_INSTALL_PREFIX=stage ..
/project-root/build> cmake --build . --target=install --config=Release

The first two lines create the out-of-source build directory
The third line generates the build system specifying where to put the installation result (which I always place in ./project-root/build/stage - the path is always considered relative to the current directory if it is not absolute)
The fourth line builds the project configured in . with the buildsystem configured in the line before. It will execute the install target which also builds all necessary dependent targets if they need to be built and then copies the files into the CMAKE_INSTALL_PREFIX (which in this case is ./project-root/build/stage. For multi-configuration builds, like in Visual Studio, you can also specify the configuration with the optional --config <config> flag.
The good part when using the cmake --build command is that it works for all generators (i.e. makefiles and Visual Studio) without needing different commands.

Afterwards I use the installed files to create packages or include them in other projects...

error: expected primary-expression before ')' token (C)

You're passing a type as an argument, not an object. You need to do characterSelection(screen, test); where test is of type SelectionneNonSelectionne.

Where can I find error log files?

I am using Cent OS 6.6 with Apache and for me error log files are in

/usr/local/apache/log

Number of days between past date and current date in Google spreadsheet

I used your idea, and found the difference and then just divided by 365 days. Worked a treat.

=MINUS(F2,TODAY())/365

Then I shifted my cell properties to not display decimals.

Interfaces — What's the point?

You will get interfaces, when you will need them :) You can study examples, but you need the Aha! effect to really get them.

Now that you know what interfaces are, just code without them. Sooner or later you will run into a problem, where the use of interfaces will be the most natural thing to do.

What's the difference between getPath(), getAbsolutePath(), and getCanonicalPath() in Java?

I find I rarely have need to use getCanonicalPath() but, if given a File with a filename that is in DOS 8.3 format on Windows, such as the java.io.tmpdir System property returns, then this method will return the "full" filename.

How to set corner radius of imageView?

You can define border radius of any view providing an "User defined Runtime Attributes", providing key path "layer.cornerRadius" of type string and then the value of radius you need ;) See attached images below:

Configuring in XCode

Is it possible to use a batch file to establish a telnet session, send a command and have the output written to a file?

First of all, a caveat. Why do you want to use telnet? telnet is an old protocol, unsafe and impractical for remote access. It's been (almost)totally replaced by ssh.

To answer your questions, it depends. It depends on the telnet client you use. If you use microsoft telnet, you can't. Microsoft telnet does not have any mean to send commands from a batch file or a command line.

how to download file using AngularJS and calling MVC API?

using FileSaver.js solved my issue thanks for help, below code helped me

'$'

 DownloadClaimForm: function (claim) 
{
 url = baseAddress + "DownLoadFile";
 return  $http.post(baseAddress + "DownLoadFile", claim, {responseType: 'arraybuffer' })
                            .success(function (data) {
                                var file = new Blob([data], { type: 'application/pdf' });
                                saveAs(file, 'Claims.pdf');
                            });


    }

Oracle client ORA-12541: TNS:no listener

You need to set oracle to listen on all ip addresses (by default, it listens only to localhost connections.)

Step 1 - Edit `listener.ora`

This file is located in:

Windows: %ORACLE_HOME%\network\admin\listener.ora.
Linux: $ORACLE_HOME/network/admin/listener.ora

Replace localhost with 0.0.0.0

# ...

LISTENER =
  (DESCRIPTION_LIST =
    (DESCRIPTION =
      (ADDRESS = (PROTOCOL = IPC)(KEY = EXTPROC1521))
      (ADDRESS = (PROTOCOL = TCP)(HOST = 0.0.0.0)(PORT = 1521))
    )
  )

# ...

Step 2 - Restart Oracle services

Windows: WinKey + r
```
services.msc
```
Linux (CentOs):
```
sudo systemctl restart oracle-xe
```

Highcharts - how to have a chart with dynamic height?

I had the same problem and I fixed it with:

<div id="container" style="width: 100%; height: 100%; position:absolute"></div>

The chart fits perfect to the browser even if I resize it. You can change the percentage according to your needs.

Kotlin: How to get and set a text to TextView in Android using Kotlin?

Yes its late - but may help someone on reference

xml with EditText, Button and TextView

onClick on Button will update the value from EditText to TextView

        <EditText
            android:id="@+id/et_id"
            android:layout_width="match_parent"
            android:layout_height="wrap_content"/>

        <Button
            android:id="@+id/btn_submit_id"
            android:layout_width="match_parent"
            android:layout_height="wrap_content"/>

        <TextView
            android:id="@+id/txt_id"
            android:layout_width="match_parent"
            android:layout_height="wrap_content"/>

Look at the code do the action in your class

Don't need to initialize the id's of components like in Java. You can do it by their xml Id's

override fun onCreate(savedInstanceState: Bundle?) {
        super.onCreate(savedInstanceState)
        setContentView(R.layout.activity_sample)

        btn_submit_id.setOnClickListener {
            txt_id.setText(et_id.text);
        }
    }

also you can set value in TextView like,

textview.text = "your value"

Add space between two particular <td>s

my choice was to add a td between the two td tags and set the width to 25px. It can be more or less to your liking. This may be cheesy but it is simple and it works.

Easy login script without database

if you dont have a database, you will have to hardcode the login details in your code, or read it from a flat file on disk.

Printing all variables value from a class

Another simple approach is to let Lombok generate the toString method for you.

For this:

Simply add Lombok to your project
Add the annotation @ToString to the definition of your class
Compile your class/project, and it is done

So for example in your case, your class would look like this:

@ToString
public class Contact {
    private String name;
    private String location;
    private String address;
    private String email;
    private String phone;
    private String fax;

    // Getters and setters.
}

Example of output in this case:

Contact(name=John, location=USA, address=SF, [email protected], phone=99999, fax=88888)

More details about how to use the annotation @ToString.

NB: You can also let Lombok generate the getters and setters for you, here is the full feature list.

Is it safe to shallow clone with --depth 1, create commits, and pull updates again?

Note that Git 1.9/2.0 (Q1 2014) has removed that limitation.
See commit 82fba2b, from Nguy?n Thái Ng?c Duy (pclouds):

Now that git supports data transfer from or to a shallow clone, these limitations are not true anymore.

The documentation now reads:

--depth <depth>::

Create a 'shallow' clone with a history truncated to the specified number of revisions.

That stems from commits like 0d7d285, f2c681c, and c29a7b8 which support clone, send-pack /receive-pack with/from shallow clones.
smart-http now supports shallow fetch/clone too.

All the details are in "shallow.c: the 8 steps to select new commits for .git/shallow".

Update June 2015: Git 2.5 will even allow for fetching a single commit!
(Ultimate shallow case)

Update January 2016: Git 2.8 (Mach 2016) now documents officially the practice of getting a minimal history.
See commit 99487cf, commit 9cfde9e (30 Dec 2015), commit 9cfde9e (30 Dec 2015), commit bac5874 (29 Dec 2015), and commit 1de2e44 (28 Dec 2015) by Stephen P. Smith (``).
^{(Merged by Junio C Hamano -- gitster -- in commit 7e3e80a, 20 Jan 2016)}

This is "Documentation/user-manual.txt"

A <<def_shallow_clone,shallow clone>> is created by specifying the git-clone --depth switch.
The depth can later be changed with the git-fetch --depth switch, or full history restored with --unshallow.

Merging inside a <<def_shallow_clone,shallow clone>> will work as long as a merge base is in the recent history.
Otherwise, it will be like merging unrelated histories and may have to result in huge conflicts.
This limitation may make such a repository unsuitable to be used in merge based workflows.

Update 2020:

git 2.11.1 introduced option git fetch --shallow-exclude= to prevent fetching all history
git 2.11.1 introduced option git fetch --shallow-since= to prevent fetching old commits.

For more on the shallow clone update process, see "How to update a git shallow clone?".

As commented by Richard Michael:

to backfill history: git pull --unshallow

And Olle Härstedt adds in the comments:

To backfill part of the history: git fetch --depth=100.

New line in JavaScript alert box

In C# I did:

alert('Text\\n\\nSome more text');

It display as:

Text

Some more text

Android 6.0 multiple permissions

Simple way to ask multiple permission,

https://github.com/sachinvarma/EasyPermission

How to add :

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

implementation 'com.github.sachinvarma:EasyPermission:1.0.1'

How to ask permission:

 List<String> permission = new ArrayList<>();
 permission.add(EasyPermissionList.READ_EXTERNAL_STORAGE);
 permission.add(EasyPermissionList.ACCESS_FINE_LOCATION);

 new EasyPermissionInit(MainActivity.this, permission);

For more Details - >

https://github.com/sachinvarma/EasyPermission/blob/master/app/src/main/java/com/sachinvarma/easypermissionsample/MainActivity.java

It may help someone in future.

Float right and position absolute doesn't work together

Perhaps you should divide your content like such using floats:

<div style="overflow: auto;">
    <div style="float: left; width: 600px;">
        Here is my content!
    </div>
    <div style="float: right; width: 300px;">
        Here is my sidebar!
    </div>
</div>

Notice the overflow: auto;, this is to ensure that you have some height to your container. Floating things takes them out of the DOM, to ensure that your elements below don't overlap your wandering floats, set a container div to have an overflow: auto (or overflow: hidden) to ensure that floats are accounted for when drawing your height. Check out more information on floats and how to use them here.

Using R to download zipped data file, extract, and import data

I found that the following worked for me. These steps come from BTD's YouTube video, Managing Zipfile's in R:

zip.url <- "url_address.zip"

dir <- getwd()

zip.file <- "file_name.zip"

zip.combine <- as.character(paste(dir, zip.file, sep = "/"))

download.file(zip.url, destfile = zip.combine)

unzip(zip.file)

MySQL: how to get the difference between two timestamps in seconds

How about "TIMESTAMPDIFF":

SELECT TIMESTAMPDIFF(SECOND,'2009-05-18','2009-07-29') from `post_statistics`

https://dev.mysql.com/doc/refman/5.7/en/date-and-time-functions.html#function_timestampdiff

Erase the current printed console line

i iterates through char array words. j keeps track of word length. "\b \b" erases word while backing over line.

#include<stdio.h>

int main()
{
    int i = 0, j = 0;

    char words[] = "Hello Bye";

    while(words[i]!='\0')
    {
        if(words[i] != ' ') {
            printf("%c", words[i]);
        fflush(stdout);
        }
        else {
            //system("ping -n 1 127.0.0.1>NUL");  //For Microsoft OS
            system("sleep 0.25");
            while(j-->0) {
                printf("\b \b");
            }
        }

        i++;
        j++;
    }

printf("\n");                   
return 0;
}

how to take user input in Array using java?

import java.util.Scanner;

class Example{

//Checks to see if a string is consider an integer.

public static boolean isInteger(String s){

    if(s.isEmpty())return false;

    for (int i = 0; i <s.length();++i){

        char c = s.charAt(i);

        if(!Character.isDigit(c) && c !='-')

            return false;
    }

    return true;
}

//Get integer. Prints out a prompt and checks if the input is an integer, if not it will keep asking.

public static int getInteger(String prompt){
    Scanner input = new Scanner(System.in);
    String in = "";
    System.out.println(prompt);
    in = input.nextLine();
    while(!isInteger(in)){
        System.out.println(prompt);
        in = input.nextLine();
    }
    input.close();
    return Integer.parseInt(in);
}

public static void main(String[] args){
    int [] a = new int[6];
    for (int i = 0; i < a.length;++i){
        int tmp = getInteger("Enter integer for array_"+i+": ");//Force to read an int using the methods above.
        a[i] = tmp;
    }

}

}

How to call a stored procedure (with parameters) from another stored procedure without temp table

You can call a stored procedure from another stored procedure by using the EXECUTE command.

Say your procedure is X. Then in X you can use

EXECUTE PROCEDURE Y () RETURNING_VALUES RESULT;"

How to parse JSON string in Typescript

Type-safe `JSON.parse`

You can continue to use JSON.parse, as TS is a JS superset. There is still a problem left: JSON.parse returns any, which undermines type safety. Here are two options for stronger types:

1. User-defined type guards (playground)

Custom type guards are the simplest solution and often sufficient for external data validation:

// For example, you expect to parse a given value with `MyType` shape
type MyType = { name: string; description: string; }

// Validate this value with a custom type guard
function isMyType(o: any): o is MyType {
  return "name" in o && "description" in o
}

A JSON.parse wrapper can then take a type guard as input and return the parsed, typed value:

const safeJsonParse = <T>(guard: (o: any) => o is T) => (text: string): ParseResult<T> => {
  const parsed = JSON.parse(text)
  return guard(parsed) ? { parsed, hasError: false } : { hasError: true }
}

type ParseResult<T> =
  | { parsed: T; hasError: false; error?: undefined }
  | { parsed?: undefined; hasError: true; error?: unknown }

Usage example:

const json = '{ "name": "Foo", "description": "Bar" }';
const result = safeJsonParse(isMyType)(json) // result: ParseResult<MyType>
if (result.hasError) {
  console.log("error :/")  // further error handling here
} else {
  console.log(result.parsed.description) // result.parsed now has type `MyType`
}

safeJsonParse might be extended to fail fast or try/catch JSON.parse errors.

2. External libraries

Writing type guard functions manually becomes cumbersome, if you need to validate many different values. There are libraries to assist with this task - examples (no comprehensive list):

io-ts: rel. popular (3.2k stars currently), fp-ts peer dependency, functional programming style
zod: quite new (repo: 2020-03-07), strives to be more procedural/object-oriented than io-ts
typescript-is: TS transformer for compiler API, additional wrapper like ttypescript needed
typescript-json-schema/ajv: Create JSON schema from types and validate it with ajv

More infos

php exec command (or similar) to not wait for result

You can run the command in the background by adding a & at the end of it as:

exec('run_baby_run &');

But doing this alone will hang your script because:

If a program is started with exec function, in order for it to continue running in the background, the output of the program must be redirected to a file or another output stream. Failing to do so will cause PHP to hang until the execution of the program ends.

So you can redirect the stdout of the command to a file, if you want to see it later or to /dev/null if you want to discard it as:

exec('run_baby_run > /dev/null &');

How to use the pass statement?

Besides its use as a placeholder for unimplemented functions, pass can be useful in filling out an if-else statement ("Explicit is better than implicit.")

def some_silly_transform(n):
    # Even numbers should be divided by 2
    if n % 2 == 0:
        n /= 2
        flag = True
    # Negative odd numbers should return their absolute value
    elif n < 0:
        n = -n
        flag = True
    # Otherwise, number should remain unchanged
    else:
        pass

Of course, in this case, one would probably use return instead of assignment, but in cases where mutation is desired, this works best.

The use of pass here is especially useful to warn future maintainers (including yourself!) not to put redundant steps outside of the conditional statements. In the example above, flag is set in the two specifically mentioned cases, but not in the else-case. Without using pass, a future programmer might move flag = True to outside the condition—thus setting flag in all cases.

Another case is with the boilerplate function often seen at the bottom of a file:

if __name__ == "__main__":
    pass

In some files, it might be nice to leave that there with pass to allow for easier editing later, and to make explicit that nothing is expected to happen when the file is run on its own.

Finally, as mentioned in other answers, it can be useful to do nothing when an exception is caught:

try:
    n[i] = 0
except IndexError:
    pass

Appending pandas dataframes generated in a for loop

you can try this.

data_you_need=pd.DataFrame()
for infile in glob.glob("*.xlsx"):
    data = pandas.read_excel(infile)
    data_you_need=data_you_need.append(data,ignore_index=True)

I hope it can help.

Underscore prefix for property and method names in JavaScript

Welcome to 2019!

It appears a proposal to extend class syntax to allow for # prefixed variable to be private was accepted. Chrome 74 ships with this support.

_ prefixed variable names are considered private by convention but are still public.

This syntax tries to be both terse and intuitive, although it's rather different from other programming languages.

Why was the sigil # chosen, among all the Unicode code points?

@ was the initial favorite, but it was taken by decorators. TC39 considered swapping decorators and private state sigils, but the committee decided to defer to the existing usage of transpiler users.

_ would cause compatibility issues with existing JavaScript code, which has allowed _ at the start of an identifier or (public) property name for a long time.

This proposal reached Stage 3 in July 2017. Since that time, there has been extensive thought and lengthy discussion about various alternatives. In the end, this thought process and continued community engagement led to renewed consensus on the proposal in this repository. Based on that consensus, implementations are moving forward on this proposal.

See https://caniuse.com/#feat=mdn-javascript_classes_private_class_fields

Programs & Examples On #Formtastic