Programs & Examples On #Bisect

ModuleNotFoundError: What does it mean __main__ is not a package?

Just use the name of the main folder which the .py file is in.

from problem_set_02.p_02_paying_debt_off_in_a_year import compute_balance_after

Style bottom Line in Android

A Simple solution :

Create a drawable file as edittext_stroke.xml in drawable folder. Add the below code:

<?xml version="1.0" encoding="utf-8"?>
<shape xmlns:android="http://schemas.android.com/apk/res/android"
    android:shape="line"
   >
    <stroke
        android:width="1dp"
        android:color="@android:color/white" >
    </stroke>
</shape>

In layout file , add the drawable to edittext as

android:drawableBottom="@drawable/edittext_stroke"

<EditText
      android:textColor="@android:color/white"
      android:layout_width="match_parent"
      android:layout_height="wrap_content"
      android:drawableBottom="@drawable/edittext_stroke"
      />

Find which commit is currently checked out in Git

Use git show, which also shows you the commit message, and defaults to the current commit when given no arguments.

Binary search (bisection) in Python

Check out the examples on Wikipedia http://en.wikipedia.org/wiki/Binary_search_algorithm

def binary_search(a, key, imin=0, imax=None):
    if imax is None:
        # if max amount not set, get the total
        imax = len(a) - 1

    while imin <= imax:
        # calculate the midpoint
        mid = (imin + imax)//2
        midval = a[mid]

        # determine which subarray to search
        if midval < key:
            # change min index to search upper subarray
            imin = mid + 1
        elif midval > key:
            # change max index to search lower subarray
            imax = mid - 1
        else:
            # return index number 
            return mid
    raise ValueError

What is the correct way to represent null XML elements?

It depends on how you validate your XML. If you use XML Schema validation, the correct way of representing null values is with the xsi:nil attribute.

[Source]

JSON - Iterate through JSONArray

You could try my (*heavily borrowed from various sites) recursive method to go through all JSON objects and JSON arrays until you find JSON elements. This example actually searches for a particular key and returns all values for all instances of that key. 'searchKey' is the key you are looking for.

ArrayList<String> myList = new ArrayList<String>();
myList = findMyKeyValue(yourJsonPayload,null,"A"); //if you only wanted to search for A's values

    private ArrayList<String> findMyKeyValue(JsonElement element, String key, String searchKey) {

    //OBJECT
    if(element.isJsonObject()) {
        JsonObject jsonObject = element.getAsJsonObject();

        //loop through all elements in object

        for (Map.Entry<String,JsonElement> entry : jsonObject.entrySet()) {
            JsonElement array = entry.getValue();
            findMyKeyValue(array, entry.getKey(), searchKey);

        }

    //ARRAY
    } else if(element.isJsonArray()) {
        //when an array is found keep 'key' as that is the array's name i.e. pass it down

        JsonArray jsonArray = element.getAsJsonArray();

        //loop through all elements in array
        for (JsonElement childElement : jsonArray) {
            findMyKeyValue(childElement, key, searchKey);
        }

    //NEITHER
    } else {

        //System.out.println("SKey: " + searchKey + " Key: " + key );

            if (key.equals(searchKey)){
                listOfValues.add(element.getAsString());
            }
    }
    return listOfValues;
}

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

I had the same issue when using the alpine image.

My .sh file had the following first line:

#!/bin/bash

Alpine does not have bash. So changing the line to

#!/bin/sh

or installing bash with

apk add --no-cache bash

solved the issue for me.

Resolving a Git conflict with binary files

You have to resolve the conflict manually (copying the file over) and then commit the file (no matter if you copied it over or used the local version) like this

git commit -a -m "Fix merge conflict in test.foo"

Git normally autocommits after merging, but when it detects conflicts it cannot solve by itself, it applies all patches it figured out and leaves the rest for you to resolve and commit manually. The Git Merge Man Page, the Git-SVN Crash Course or this blog entry might shed some light on how it's supposed to work.

Edit: See the post below, you don't actually have to copy the files yourself, but can use

git checkout --ours -- path/to/file.txt
git checkout --theirs -- path/to/file.txt

to select the version of the file you want. Copying / editing the file will only be necessary if you want a mix of both versions.

Please mark mipadis answer as the correct one.

ssh server connect to host xxx port 22: Connection timed out on linux-ubuntu

Update the security group of that instance. Your local IP must have updated. Every time it’s IP flips. You will have to go update the Security group.

Apache Tomcat :java.net.ConnectException: Connection refused

The meaning of this exception is explained here: https://bz.apache.org/bugzilla/show_bug.cgi?id=27829

Summary: Java dies, Tomcat shut down hook is called, exception is thrown.

So if a firewall prevents the shutdown message from reaching Tomcat, Java will eventually die first (ex during system reboot/shutdown), and the exception will appear.

There are other possibilities.

In my case, my problem had something to do with my initscript (Linux) being incorrectly installed. That implied Java was getting killed by the OS during shutdown/reboot and not as a result of the script. The solution as simple as this:

chkconfig --del initscript
chkconfig --add initscript

Before the fix I had the following in rc.d:

find /etc/rc.d | grep initscript | sort
/etc/rc.d/init.d/initscript
/etc/rc.d/rc2.d/S85initscript
/etc/rc.d/rc3.d/S85initscript
/etc/rc.d/rc4.d/S85initscript
/etc/rc.d/rc5.d/S85initscript

After the fix:

find /etc/rc.d | grep initscript | sort
/etc/rc.d/init.d/initscript
/etc/rc.d/rc0.d/K15initscript
/etc/rc.d/rc1.d/K15initscript
/etc/rc.d/rc2.d/K15initscript
/etc/rc.d/rc3.d/K15initscript
/etc/rc.d/rc4.d/K15initscript
/etc/rc.d/rc5.d/S85initscript
/etc/rc.d/rc6.d/K15initscript

Conclusion: if you get this exception, make sure Tomcat is shutdown properly, not as a result of Java being terminated. Check your firewall, shutdown scripts etc.

VBA (Excel) Initialize Entire Array without Looping

For VBA you need to initialise in two lines.

Sub TestArray()

Dim myArray
myArray = Array(1, 2, 4, 8)

End Sub

Getting each individual digit from a whole integer

This solution gives correct results over the entire range [0,UINT_MAX] without requiring digits to be buffered.

It also works for wider types or signed types (with positive values) with appropriate type changes.

This kind of approach is particularly useful on tiny environments (e.g. Arduino bootloader) because it doesn't end up pulling in all the printf() bloat (when printf() isn't used for demo output) and uses very little RAM. You can get a look at value just by blinking a single led :)

#include <limits.h>
#include <stdio.h>

int
main (void)
{
  unsigned int score = 42;   // Works for score in [0, UINT_MAX]

  printf ("score via printf:     %u\n", score);   // For validation

  printf ("score digit by digit: ");
  unsigned int div = 1;
  unsigned int digit_count = 1;
  while ( div <= score / 10 ) {
    digit_count++;
    div *= 10;
  }
  while ( digit_count > 0 ) {
    printf ("%d", score / div);
    score %= div;
    div /= 10;
    digit_count--;
  }
  printf ("\n");

  return 0;
}

C#: How to add subitems in ListView

Generally:

ListViewItem item = new ListViewItem("Column1Text")
   { Tag = optionalRefToSourceObject };

item.SubItems.Add("Column2Text");
item.SubItems.Add("Column3Text");
myListView.Items.Add(item);

How to make responsive table

To make a responsive table, you can make the width of each td 100% and insert a related heading in the td on mobile browsers (that are less 768px width.)

Here is a website that demonstrates this technique: http://www.quizexpo.com/list-of-banks-in-india/

How to create a DataTable in C# and how to add rows?

DataTable dt=new DataTable();
Datacolumn Name = new DataColumn("Name");
Name.DataType= typeoff(string);
Name.AllowDBNull=false; //set as null or not the default is true i.e null
Name.MaxLength=20; //sets the length the default is -1 which is max(no limit)
dt.Columns.Add(Name);
Datacolumn Age = new DataColumn("Age", typeoff(int));`

dt.Columns.Add(Age);

DataRow dr=dt.NewRow();

dr["Name"]="Mohammad Adem"; // or dr[0]="Mohammad Adem";
dr["Age"]=33; // or dr[1]=33;
dt.add.rows(dr);
dr=dt.NewRow();

dr["Name"]="Zahara"; // or dr[0]="Zahara";
dr["Age"]=22; // or dr[1]=22;
dt.rows.add(dr);
Gv.DataSource=dt;
Gv.DataBind();

Selenium WebDriver and DropDown Boxes

You can use this

(new SelectElement(driver.FindElement(By.Id(""))).SelectByText("");

How to get current moment in ISO 8601 format with date, hour, and minute?

Joda-Time

Update: The Joda-Time project is now in maintenance mode, with the team advising migration to the java.time classes. For Java 6 & 7, see the ThreeTen-Backport project, further adapted for Android in the ThreeTenABP project.

Using the Joda-Time library…

String output = new DateTime( DateTimeZone.UTC ).toString() ;

This is thread-safe. Joda-Time creates new immutable objects rather than changing existing objects.

If you truly intended to ask for a format without seconds, resolving to minutes, then use one of the many other built-in formatters in Joda-Time.

DateTime now = new DateTime( DateTimeZone.UTC ) ;
String output = ISODateTimeFormat.dateHourMinute.print( now ) ;

java.time

For Java 8 and later, Joda-Time continues to work. But the built-in java.time framework supplants Joda-Time. So migrate your code from Joda-Time to java.time as soon as is convenient.

See my other Answer for a modern solution.


About java.time

The java.time framework is built into Java 8 and later. These classes supplant the troublesome old legacy date-time classes such as java.util.Date, Calendar, & SimpleDateFormat.

The Joda-Time project, now in maintenance mode, advises migration to the java.time classes.

To learn more, see the Oracle Tutorial. And search Stack Overflow for many examples and explanations. Specification is JSR 310.

You may exchange java.time objects directly with your database. Use a JDBC driver compliant with JDBC 4.2 or later. No need for strings, no need for java.sql.* classes.

Where to obtain the java.time classes?

The ThreeTen-Extra project extends java.time with additional classes. This project is a proving ground for possible future additions to java.time. You may find some useful classes here such as Interval, YearWeek, YearQuarter, and more.

How do I compare version numbers in Python?

There is packaging package available, which will allow you to compare versions as per PEP-440, as well as legacy versions.

>>> from packaging.version import Version, LegacyVersion
>>> Version('1.1') < Version('1.2')
True
>>> Version('1.2.dev4+deadbeef') < Version('1.2')
True
>>> Version('1.2.8.5') <= Version('1.2')
False
>>> Version('1.2.8.5') <= Version('1.2.8.6')
True

Legacy version support:

>>> LegacyVersion('1.2.8.5-5-gdeadbeef')
<LegacyVersion('1.2.8.5-5-gdeadbeef')>

Comparing legacy version with PEP-440 version.

>>> LegacyVersion('1.2.8.5-5-gdeadbeef') < Version('1.2.8.6')
True

check if variable empty

To check for null values you can use is_null() as is demonstrated below.

if (is_null($value)) {
   $value = "MY TEXT"; //define to suit
}

UIButton: how to center an image and a text using imageEdgeInsets and titleEdgeInsets?

Found how.

First, configure the text of titleLabel (because of styles, i.e, bold, italic, etc). Then, use setTitleEdgeInsets considering the width of your image:

[button setTitleColor:[UIColor blackColor] forState:UIControlStateNormal];
[button setTitle:title forState:UIControlStateNormal];
[button.titleLabel setFont:[UIFont boldSystemFontOfSize:10.0]];

// Left inset is the negative of image width.
[button setTitleEdgeInsets:UIEdgeInsetsMake(0.0, -image.size.width, -25.0, 0.0)]; 

After that, use setTitleEdgeInsets considering the width of text bounds:

[button setImage:image forState:UIControlStateNormal];

// Right inset is the negative of text bounds width.
[button setImageEdgeInsets:UIEdgeInsetsMake(-15.0, 0.0, 0.0, -button.titleLabel.bounds.size.width)];

Now the image and the text will be centered (in this example, the image appears above the text).

Cheers.

Git command to checkout any branch and overwrite local changes

Couple of points:

  • I believe git stash + git stash drop could be replaced with git reset --hard
  • ... or, even shorter, add -f to checkout command:

    git checkout -f -b $branch
    

    That will discard any local changes, just as if git reset --hard was used prior to checkout.

As for the main question: instead of pulling in the last step, you could just merge the appropriate branch from the remote into your local branch: git merge $branch origin/$branch, I believe it does not hit the remote. If that is the case, it removes the need for credensials and hence, addresses your biggest concern.

Check to see if cURL is installed locally?

In the Terminal, type:

$ curl -V

That's a capital V for the version

Accessing an SQLite Database in Swift

You can use this library in Swift for SQLite https://github.com/pmurphyjam/SQLiteDemo

SQLiteDemo

SQLite Demo using Swift with SQLDataAccess class written in Swift

Adding to Your Project

You only need three files to add to your project * SQLDataAccess.swift * DataConstants.swift * Bridging-Header.h Bridging-Header must be set in your Xcode's project 'Objective-C Bridging Header' under 'Swift Compiler - General'

Examples for Use

Just follow the code in ViewController.swift to see how to write simple SQL with SQLDataAccess.swift First you need to open the SQLite Database your dealing with

    let db = SQLDataAccess.shared
    db.setDBName(name:"SQLite.db")
    let opened = db.openConnection(copyFile:true)

If openConnection succeeded, now you can do a simple insert into Table AppInfo

    //Insert into Table AppInfo
    let status = db.executeStatement("insert into AppInfo (name,value,descrip,date) values(?,?,?,?)",
    ”SQLiteDemo","1.0.2","unencrypted",Date())
    if(status)
    {
        //Read Table AppInfo into an Array of Dictionaries
        let results = db.getRecordsForQuery("select * from AppInfo ")
        NSLog("Results = \(results)")
    }

See how simple that was!

The first term in db.executeStatement is your SQL as String, all the terms that follow are a variadic argument list of type Any, and are your parameters in an Array. All these terms are separated by commas in your list of SQL arguments. You can enter Strings, Integers, Date’s, and Blobs right after the sequel statement since all of these terms are considered to be parameters for the sequel. The variadic argument array just makes it convenient to enter all your sequel in just one executeStatement or getRecordsForQuery call. If you don’t have any parameters, don’t enter anything after your SQL.

The results array is an Array of Dictionary’s where the ‘key’ is your tables column name, and the ‘value’ is your data obtained from SQLite. You can easily iterate through this array with a for loop or print it out directly or assign these Dictionary elements to custom data object Classes that you use in your View Controllers for model consumption.

    for dic in results as! [[String:AnyObject]] {
       print(“result = \(dic)”)
    }

SQLDataAccess will store, text, double, float, blob, Date, integer and long long integers. For Blobs you can store binary, varbinary, blob.

For Text you can store char, character, clob, national varying character, native character, nchar, nvarchar, varchar, variant, varying character, text.

For Dates you can store datetime, time, timestamp, date.

For Integers you can store bigint, bit, bool, boolean, int2, int8, integer, mediumint, smallint, tinyint, int.

For Doubles you can store decimal, double precision, float, numeric, real, double. Double has the most precision.

You can even store Nulls of type Null.

In ViewController.swift a more complex example is done showing how to insert a Dictionary as a 'Blob'. In addition SQLDataAccess understands native Swift Date() so you can insert these objects with out converting, and it will convert them to text and store them, and when retrieved convert them back from text to Date.

Of course the real power of SQLite is it's Transaction capability. Here you can literally queue up 400 SQL statements with parameters and insert them all at once which is really powerful since it's so fast. ViewController.swift also shows you an example of how to do this. All you're really doing is creating an Array of Dictionaries called 'sqlAndParams', in this Array your storing Dictionaries with two keys 'SQL' for the String sequel statement or query, and 'PARAMS' which is just an Array of native objects SQLite understands for that query. Each 'sqlParams' which is an individual Dictionary of sequel query plus parameters is then stored in the 'sqlAndParams' Array. Once you've created this array, you just call.

    let status = db.executeTransaction(sqlAndParams)
    if(status)
    {
        //Read Table AppInfo into an Array of Dictionaries for the above Transactions
        let results = db.getRecordsForQuery("select * from AppInfo ")
        NSLog("Results = \(results)")
    }

In addition all executeStatement and getRecordsForQuery methods can be done with simple String for SQL query and an Array for the parameters needed by the query.

    let sql : String = "insert into AppInfo (name,value,descrip) values(?,?,?)"
    let params : Array = ["SQLiteDemo","1.0.0","unencrypted"]
    let status = db.executeStatement(sql, withParameters: params)
    if(status)
    {
        //Read Table AppInfo into an Array of Dictionaries for the above Transactions
        let results = db.getRecordsForQuery("select * from AppInfo ")
        NSLog("Results = \(results)")
    }

An Objective-C version also exists and is called the same SQLDataAccess, so now you can choose to write your sequel in Objective-C or Swift. In addition SQLDataAccess will also work with SQLCipher, the present code isn't setup yet to work with it, but it's pretty easy to do, and an example of how to do this is actually in the Objective-C version of SQLDataAccess.

SQLDataAccess is a very fast and efficient class, and can be used in place of CoreData which really just uses SQLite as it's underlying data store without all the CoreData core data integrity fault crashes that come with CoreData.

Is the order of elements in a JSON list preserved?

"Is the order of elements in a JSON list maintained?" is not a good question. You need to ask "Is the order of elements in a JSON list maintained when doing [...] ?" As Felix King pointed out, JSON is a textual data format. It doesn't mutate without a reason. Do not confuse a JSON string with a (JavaScript) object.

You're probably talking about operations like JSON.stringify(JSON.parse(...)). Now the answer is: It depends on the implementation. 99%* of JSON parsers do not maintain the order of objects, and do maintain the order of arrays, but you might as well use JSON to store something like

{
    "son": "David",
    "daughter": "Julia",
    "son": "Tom",
    "daughter": "Clara"
}

and use a parser that maintains order of objects.

*probably even more :)

How to redirect Valgrind's output to a file?

By default, Valgrind writes its output to stderr. So you need to do something like:

valgrind a.out > log.txt 2>&1

Alternatively, you can tell Valgrind to write somewhere else; see http://valgrind.org/docs/manual/manual-core.html#manual-core.comment (but I've never tried this).

How to increase time in web.config for executing sql query

You should add the httpRuntime block and deal with executionTimeout (in seconds).

<?xml version="1.0" encoding="utf-8" ?>
<configuration>
...
 <system.web>
   <httpRuntime executionTimeout="90" maxRequestLength="4096"
    useFullyQualifiedRedirectUrl="false"
    minFreeThreads="8"
    minLocalRequestFreeThreads="4"
    appRequestQueueLimit="100" />
 </system.web>
... 
</configuration>

For more information, please, see msdn page.

How to append data to a json file?

this, work for me :

with open('file.json', 'a') as outfile:
    outfile.write(json.dumps(data))
    outfile.write(",")
    outfile.close()

Using ffmpeg to change framerate

With re-encoding:

ffmpeg -y -i seeing_noaudio.mp4 -vf "setpts=1.25*PTS" -r 24 seeing.mp4

Without re-encoding:

First step - extract video to raw bitstream

ffmpeg -y -i seeing_noaudio.mp4 -c copy -f h264 seeing_noaudio.h264

Remux with new framerate

ffmpeg -y -r 24 -i seeing_noaudio.h264 -c copy seeing.mp4

What's sizeof(size_t) on 32-bit vs the various 64-bit data models?

size_t is defined by the C standard to be the unsigned integer return type of the sizeof operator (C99 6.3.5.4.4), and the argument of malloc and friends (C99 7.20.3.3 etc). The actual range is set such that the maximum (SIZE_MAX) is at least 65535 (C99 7.18.3.2).

However, this doesn't let us determine sizeof(size_t). The implementation is free to use any representation it likes for size_t - so there is no upper bound on size - and the implementation is also free to define a byte as 16-bits, in which case size_t can be equivalent to unsigned char.

Putting that aside, however, in general you'll have 32-bit size_t on 32-bit programs, and 64-bit on 64-bit programs, regardless of the data model. Generally the data model only affects static data; for example, in GCC:

`-mcmodel=small'
     Generate code for the small code model: the program and its
     symbols must be linked in the lower 2 GB of the address space.
     Pointers are 64 bits.  Programs can be statically or dynamically
     linked.  This is the default code model.

`-mcmodel=kernel'
     Generate code for the kernel code model.  The kernel runs in the
     negative 2 GB of the address space.  This model has to be used for
     Linux kernel code.

`-mcmodel=medium'
     Generate code for the medium model: The program is linked in the
     lower 2 GB of the address space but symbols can be located
     anywhere in the address space.  Programs can be statically or
     dynamically linked, but building of shared libraries are not
     supported with the medium model.

`-mcmodel=large'
     Generate code for the large model: This model makes no assumptions
     about addresses and sizes of sections.

You'll note that pointers are 64-bit in all cases; and there's little point to having 64-bit pointers but not 64-bit sizes, after all.

Move all files except one

For bash, sth answer is correct. Here is the zsh (my shell of choice) syntax:

mv ~/Linux/Old/^Tux.png ~/Linux/New/

Requires EXTENDED_GLOB shell option to be set.

Difference between & and && in Java?

& is bitwise AND operator comparing bits of each operand.
For example,

int a = 4;
int b = 7;
System.out.println(a & b); // prints 4
//meaning in an 32 bit system
// 00000000 00000000 00000000 00000100
// 00000000 00000000 00000000 00000111
// ===================================
// 00000000 00000000 00000000 00000100


&& is logical AND operator comparing boolean values of operands only. It takes two operands indicating a boolean value and makes a lazy evaluation on them.

How do I create a user with the same privileges as root in MySQL/MariaDB?

% mysql --user=root mysql
CREATE USER 'monty'@'localhost' IDENTIFIED BY 'some_pass';
GRANT ALL PRIVILEGES ON *.* TO 'monty'@'localhost' WITH GRANT OPTION;
CREATE USER 'monty'@'%' IDENTIFIED BY 'some_pass';
GRANT ALL PRIVILEGES ON *.* TO 'monty'@'%' WITH GRANT OPTION;
CREATE USER 'admin'@'localhost';
GRANT RELOAD,PROCESS ON *.* TO 'admin'@'localhost';
CREATE USER 'dummy'@'localhost';
FLUSH PRIVILEGES;

Can I create view with parameter in MySQL?

Actually if you create func:

create function p1() returns INTEGER DETERMINISTIC NO SQL return @p1;

and view:

create view h_parm as
select * from sw_hardware_big where unit_id = p1() ;

Then you can call a view with a parameter:

select s.* from (select @p1:=12 p) parm , h_parm s;

I hope it helps.

How to paginate with Mongoose in Node.js?

This is a sample example you can try this,

var _pageNumber = 2,
  _pageSize = 50;

Student.count({},function(err,count){
  Student.find({}, null, {
    sort: {
      Name: 1
    }
  }).skip(_pageNumber > 0 ? ((_pageNumber - 1) * _pageSize) : 0).limit(_pageSize).exec(function(err, docs) {
    if (err)
      res.json(err);
    else
      res.json({
        "TotalCount": count,
        "_Array": docs
      });
  });
 });

iPhone/iPad browser simulator?

EDIT 2020: Most of these are basically just to test resolution stuff, some of them even outdated, sadly, mobile browser development went sideways with desktop (especially in Apple), therefore one can't really "emulate" a real phone with these as mentioned with comment.

To emulate real phones, often the best choice is to download a desktop app which, for Windows, is usually paid/freemium, on Mac just use the Xcode one (but I doubt Mac people are looking for this Q/A).

Freemium online easy to use that I found recently is Appetize.io it seems to really render the screen according to network, but honestly I didn't really dig into whether it also has identical features and indentically missing features as real iOS.

Online simulators / emulators I use

1) recombu

Fine simulator which - unlike resizing browser window to mobile phone dimensions - acts same as a smart phone. Don't be confused that you can't edit address bar in safari - just open deveolper tools (usually F12) and rewrite iframe's source URL to yours.
Link: http://recombu.com/mobile/interactive/ios7-demo/

2) responsimulator

Seems to work like recombu, but you can open url directly by text input and you can zoom in/out.
Link: http://www.responsimulator.com/

3) transmog

This one seems to process the webpage, but it emulates old iPhone - still handy sometimes.
Link: http://transmog.net/iphone-simulator/mobile-web-browser-emulator.php

X) google it / internet search for it

Always use google (or other internet searchers) to check for other simulators/emulators and new versions.
Link with example google search for this one:
https://www.google.cz/search?q=online+iphone+emulator

Browser device mode

If you open your browser's developer's tools (in Chrome F12), there will probably be an option to toggle device mode (in Chrome it is the little smartphone icon at top-left).
chrome device mode icon

After choosing this option GUI will change and will provide option to select device to simulate (in Chrome it is at the top - select option "Device"), after selecting device, refreshing the page is often adviced to ensure simulator's accuracy.
chrome device mode - device select option

How to properly add 1 month from now to current date in moment.js

_x000D_
_x000D_
startdate = "20.03.2020";_x000D_
    var new_date = moment(startdate, "DD-MM-YYYY").add(5,'days');_x000D_
_x000D_
     alert(new_date)
_x000D_
_x000D_
_x000D_

How to access child's state in React?

As the previous answers saids, try to move the state to a top component and modify the state through callbacks passed to it's children.

In case that you really need to access to a child state that is declared as a functional component (hooks) you can declare a ref in the parent component, then pass it as a ref attribute to the child but you need to use React.forwardRef and then the hook useImperativeHandle to declare a function you can call in the parent component.

Take a look at the following example:

const Parent = () => {
    const myRef = useRef();
    return <Child ref={myRef} />;
}

const Child = React.forwardRef((props, ref) => {
    const [myState, setMyState] = useState('This is my state!');
    useImperativeHandle(ref, () => ({getMyState: () => {return myState}}), [myState]);
})

Then you should be able to get myState in the Parent component by calling: myRef.current.getMyState();

Split Spark Dataframe string column into multiple columns

Here's another approach, in case you want split a string with a delimiter.

import pyspark.sql.functions as f

df = spark.createDataFrame([("1:a:2001",),("2:b:2002",),("3:c:2003",)],["value"])
df.show()
+--------+
|   value|
+--------+
|1:a:2001|
|2:b:2002|
|3:c:2003|
+--------+

df_split = df.select(f.split(df.value,":")).rdd.flatMap(
              lambda x: x).toDF(schema=["col1","col2","col3"])

df_split.show()
+----+----+----+
|col1|col2|col3|
+----+----+----+
|   1|   a|2001|
|   2|   b|2002|
|   3|   c|2003|
+----+----+----+

I don't think this transition back and forth to RDDs is going to slow you down... Also don't worry about last schema specification: it's optional, you can avoid it generalizing the solution to data with unknown column size.

Java Refuses to Start - Could not reserve enough space for object heap

Steps to be execute .... to resolve the Error occurred during initialization of VM Could not reserve enough space for object heap Could not create the Java virtual machine.

Step 1: Reduce the memory what earlier you used.. java -Xms128m -Xmx512m -cp simple.jar

step 2: Remove the RAM some time from the mother board and plug it and restart * may it will release the blocking heap area memory.. java -Xms512m -Xmx1024m -cp simple.jar

Hope it will work well now... :-)

Case insensitive string as HashMap key

Instead of creating your own class to validate and store case insensitive string as a HashMap key, you can use:

  1. LinkedCaseInsensitiveMap wraps a LinkedHashMap, which is a Map based on a hash table and a linked list. Unlike LinkedHashMap, it doesn't allow null key inserting. LinkedCaseInsensitiveMap preserves the original order as well as the original casing of keys while allowing calling functions like get and remove with any case.

Eg:

Map<String, Integer> linkedHashMap = new LinkedCaseInsensitiveMap<>();
linkedHashMap.put("abc", 1);
linkedHashMap.put("AbC", 2);

System.out.println(linkedHashMap);

Output: {AbC=2}

Mvn Dependency:

Spring Core is a Spring Framework module that also provides utility classes, including LinkedCaseInsensitiveMap.

<dependency>
    <groupId>org.springframework</groupId>
    <artifactId>spring-core</artifactId>
    <version>5.2.5.RELEASE</version>
</dependency>
  1. CaseInsensitiveMap is a hash-based Map, which converts keys to lower case before they are being added or retrieved. Unlike TreeMap, CaseInsensitiveMap allows null key inserting.

Eg:

Map<String, Integer> commonsHashMap = new CaseInsensitiveMap<>();
commonsHashMap.put("ABC", 1);
commonsHashMap.put("abc", 2);
commonsHashMap.put("aBc", 3);

System.out.println(commonsHashMap);

Output: {abc=3}

Dependency:

<dependency>
    <groupId>org.apache.commons</groupId>
    <artifactId>commons-collections4</artifactId>
    <version>4.4</version>
</dependency>
  1. TreeMap is an implementation of NavigableMap, which means that it always sorts the entries after inserting, based on a given Comparator. Also, TreeMap uses a Comparator to find if an inserted key is a duplicate or a new one.

Therefore, if we provide a case-insensitive String Comparator, we'll get a case-insensitive TreeMap.

Eg:

Map<String, Integer> treeMap = new TreeMap<>(String.CASE_INSENSITIVE_ORDER);
treeMap.put("ABC", 1);
treeMap.put("ABc", 2);
treeMap.put("cde", 1);
        
System.out.println(treeMap);

Output: {ABC=2, cde=1}

Port 80 is being used by SYSTEM (PID 4), what is that?

If you are running Windows Server 2012 R2 then make sure to get rid of Work Folders: http://blogs.technet.com/b/filecab/archive/2013/10/15/windows-server-2012-r2-resolving-port-conflict-with-iis-websites-and-work-folders.aspx Removing Work Folders feature under File Server worked for me.

Android: ListView elements with multiple clickable buttons

Probably you've found how to do it, but you can call

ListView.setItemsCanFocus(true)

and now your buttons will catch focus

What does $ mean before a string?

It creates an interpolated string.

From MSDN

Used to construct strings. An interpolated string expression looks like a template string that contains expressions. An interpolated string expression creates a string by replacing the contained expressions with the ToString represenations of the expressions’ results.

ex :

 var name = "Sam";
 var msg = $"hello, {name}";

 Console.WriteLine(msg); // hello, Sam

You can use expressions within the interpolated string

 var msg = $"hello, {name.ToLower()}";
 Console.WriteLine(msg); // hello, sam

The nice thing about it is that you don't need to worry about the order of parameters as you do with String.Format.

  var s = String.Format("{0},{1},{2}...{88}",p0,p1,..,p88);

Now if you want to remove some parameters you have to go and update all the counts, which is not the case anymore.

Note that the good old string.format is still relevant if you want to specify cultural info in your formatting.

No templates in Visual Studio 2017

I found the path and wrote it in the options enter image description here

MySQL Error 1093 - Can't specify target table for update in FROM clause

The inner join in your sub-query is unnecessary. It looks like you want to delete the entries in story_category where the category_id is not in the category table.

Do this:

DELETE FROM story_category 
WHERE category_id NOT IN (
    SELECT DISTINCT category.id 
    FROM category);

Instead of that:

DELETE FROM story_category 
WHERE category_id NOT IN (
    SELECT DISTINCT category.id 
    FROM category INNER JOIN
         story_category ON category_id=category.id);

Trigger 404 in Spring-MVC controller?

you can use the @ControllerAdvice to handle your Exceptions , The default behavior the @ControllerAdvice annotated class will assist all known Controllers.

so it will be called when any Controller you have throws 404 error .

like the following :

@ControllerAdvice
class GlobalControllerExceptionHandler {
    @ResponseStatus(HttpStatus.NOT_FOUND)  // 404
    @ExceptionHandler(Exception.class)
    public void handleNoTFound() {
        // Nothing to do
    }
}

and map this 404 response error in your web.xml , like the following :

<error-page>
        <error-code>404</error-code>
        <location>/Error404.html</location>
</error-page>

Hope that Helps .

Jquery array.push() not working

Your HTML should include quotes for attributes : http://jsfiddle.net/dKWnb/4/

Not required when using a HTML5 doctype - thanks @bazmegakapa

You create the array each time and add a value to it ... its working as expected ?

Moving the array outside of the live() function works fine :

var myarray = []; // more efficient than new Array()
$("#test").live("click",function() {
        myarray.push($("#drop").val());
        alert(myarray);
});

http://jsfiddle.net/dKWnb/5/

Also note that in later versions of jQuery v1.7 -> the live() method is deprecated and replaced by the on() method.

Find element's index in pandas Series

If you use numpy, you can get an array of the indecies that your value is found:

import numpy as np
import pandas as pd
myseries = pd.Series([1,4,0,7,5], index=[0,1,2,3,4])
np.where(myseries == 7)

This returns a one element tuple containing an array of the indecies where 7 is the value in myseries:

(array([3], dtype=int64),)

Running a Python script from PHP

In my case I needed to create a new folder in the www directory called scripts. Within scripts I added a new file called test.py.

I then used sudo chown www-data:root scripts and sudo chown www-data:root test.py.

Then I went to the new scripts directory and used sudo chmod +x test.py.

My test.py file it looks like this. Note the different Python version:

#!/usr/bin/env python3.5
print("Hello World!")

From php I now do this:

$message = exec("/var/www/scripts/test.py 2>&1");
print_r($message);

And you should see: Hello World!

No compiler is provided in this environment. Perhaps you are running on a JRE rather than a JDK?

An alternative if jaipster's answer does not work is to go to:
Window > Preferences > Java > Installed JREs

Then to edit the jre so that it points to the jdk and not the jre (the jre home filed in the jre package editor)

That worked for me.

Node.js throws "btoa is not defined" error

My team ran into this problem when using Node with React Native and PouchDB. Here is how we solved it...

NPM install buffer:

$ npm install --save buffer

Ensure Buffer, btoa, and atob are loaded as a globals:

global.Buffer = global.Buffer || require('buffer').Buffer;

if (typeof btoa === 'undefined') {
  global.btoa = function (str) {
    return new Buffer(str, 'binary').toString('base64');
  };
}

if (typeof atob === 'undefined') {
  global.atob = function (b64Encoded) {
    return new Buffer(b64Encoded, 'base64').toString('binary');
  };
}

What's the scope of a variable initialized in an if statement?

And note that since Python types are only checked at runtime you can have code like:

if True:
    x = 2
    y = 4
else:
    x = "One"
    y = "Two"
print(x + y)

But I'm having trouble thinking of other ways in which the code would operate without an error because of type issues.

Sql connection-string for localhost server

<add name="connstr" connectionString="Data Source=localhost;Initial Catalog=DBName;User Id=username;Password=password" providerName="System.Data.SqlClient"/>

The above also works. It ignores the username and password passed in in the connection string. I switched from an environment db to a local one, and it works fine even though my user in the connection string does not exist in this context.

How to print a Groovy variable in Jenkins?

The following code worked for me:

echo userInput

Nodejs cannot find installed module on Windows

I stumbled on this question because I want to use node.js with visual studio 2015 on my new computer with windows 10. I used node.js on windows 7 and 8 and 8.1 Never a problem node.js finding a module. I use a legacy node.js 0.10.39 because I have to use this version because of the serial and RFXCOM module.

The answer for windows 10 is to set the NODE_PATH in the enviroment variables with C:\Users\User\node_modules.

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

It is.

test.hpp:

class A {
public:
    static int a(int i);
};

test.cpp:

#include <iostream>
#include "test.hpp"


int A::a(int i) {
    return i + 2;
}

using namespace std;
int main() {
    cout << A::a(4) << endl;
}

They're not always inline, no, but the compiler can make them.

Is it better to use "is" or "==" for number comparison in Python?

>>> 2 == 2.0
True
>>> 2 is 2.0
False

Use ==

jQuery "on create" event for dynamically-created elements

There is a plugin, adampietrasiak/jquery.initialize, which is based on MutationObserver that achieves this simply.

$.initialize(".some-element", function() {
    $(this).css("color", "blue");
});

Reading Properties file in Java


You can find information on this page:
http://www.mkyong.com/java/java-properties-file-examples/

Properties prop = new Properties();
try {
    //load a properties file from class path, inside static method
    prop.load(App.class.getClassLoader().getResourceAsStream("config.properties"));

    //get the property value and print it out
    System.out.println(prop.getProperty("database"));
    System.out.println(prop.getProperty("dbuser"));
    System.out.println(prop.getProperty("dbpassword"));

} 
catch (IOException ex) {
    ex.printStackTrace();
}

How to execute a JavaScript function when I have its name as a string

To add to Jason Bunting's answer, if you're using nodejs or something (and this works in dom js, too), you could use this instead of window (and remember: eval is evil:

this['fun'+'ctionName']();

Cross origin requests are only supported for HTTP but it's not cross-domain

It works best this way. Make sure that both files are on the server. When calling the html page, make use of the web address like: http:://localhost/myhtmlfile.html, and not, C::///users/myhtmlfile.html. Make usre as well that the url passed to the json is a web address as denoted below:

$(function(){
                $('#typeahead').typeahead({
                    source: function(query, process){
                        $.ajax({
                            url: 'http://localhost:2222/bootstrap/source.php',
                            type: 'POST',
                            data: 'query=' +query,
                            dataType: 'JSON',
                            async: true,
                            success: function(data){
                                process(data);
                            }
                        });
                    }
                });
            });

Java java.sql.SQLException: Invalid column index on preparing statement

In date '?', the '?' is a literal string with value ?, not a parameter placeholder, so your query does not have any parameters. The date is a shorthand cast from (literal) string to date. You need to replace date '?' with ? to actually have a parameter.

Also if you know it is a date, then use setDate(..) and not setString(..) to set the parameter.

Decode UTF-8 with Javascript

// String to Utf8 ByteBuffer

function strToUTF8(str){
  return Uint8Array.from(encodeURIComponent(str).replace(/%(..)/g,(m,v)=>{return String.fromCodePoint(parseInt(v,16))}), c=>c.codePointAt(0))
}

// Utf8 ByteArray to string

function UTF8toStr(ba){
  return decodeURIComponent(ba.reduce((p,c)=>{return p+'%'+c.toString(16),''}))
}

Getting the text from a drop-down box

Does this get the correct answer?

document.getElementById("newSkill").innerHTML

MongoDB or CouchDB - fit for production?

We use couchdb in production and have since just before the project went under the Apache umbrella.

We use it to store everything that we might otherwise use a dbms, plus all sorts of unstructured data. Personally, I really like how you can just throw all sorts of data into it and use the views to cull what you don't need depending on the situation.

The hardest part was moving away from the dbms mindset. We wrote our own migration utils when the storage format changed just to be safe, so that wasn't really a problem.

We haven't had any negative experiences yet, but then again we haven't had the setup under any kind of huge load. I think things would work pretty well since we have two slave type servers that replicate from a single master server that gets all of the writes. I'm pretty sure that we don't have to do it that way for replication to work correctly, but it's how we set it up in the beginning and it stuck.

Angular2 Exception: Can't bind to 'routerLink' since it isn't a known native property

If you use shared modules, just add RouterModule to a Module where your component is declared and don't forget to add <router-outlet></router-outlet>

Referenced from here RouterLink does not work

How to send POST in angularjs with multiple params?

Consider a post url with parameters user and email

params object will be

 var data = {user:'john', email:'[email protected]'};
    $http({
      url: "login.php",
      method: "POST",
      params: data
    })

Setting a div's height in HTML with CSS

The short answer to your question is that you must set the height of 100% to the body and html tag, then set the height to 100% on each div element you want to make 100% the height of the page.

Convert .cer certificate to .jks

keytool comes with the JDK installation (in the bin folder):

keytool -importcert -file "your.cer" -keystore your.jks -alias "<anything>"

This will create a new keystore and add just your certificate to it.

So, you can't convert a certificate to a keystore: you add a certificate to a keystore.

initializing a boolean array in java

Arrays in Java start indexing at 0. So in your example you are referring to an element that is outside the array by one.

It should probably be something like freq[Global.iParameter[2]-1]=false;

You would need to loop through the array to initialize all of it, this line only initializes the last element.

Actually, I'm pretty sure that false is default for booleans in Java, so you might not need to initialize at all.

Best Regards

Electron: jQuery is not defined

If you are using Angular2 you can create a new js file with this code:

// jquery-electron.js

if ((!window.jQuery || !window.$) && (!!module && !!module.exports)) {
      window.jQuery = window.$ = module.exports;
}

and put it right after jquery path, in .angular-cli.json:

"scripts": [
    "../node_modules/jquery/dist/jquery.js",
    "assets/js/jquery-electron.js",
    ...
    ...
]

Combination of async function + await + setTimeout

This is a quicker fix in one-liner.

Hope this will help.

// WAIT FOR 200 MILISECONDS TO GET DATA //
await setTimeout(()=>{}, 200);

How to read text files with ANSI encoding and non-English letters?

You get the question-mark-diamond characters when your textfile uses high-ANSI encoding -- meaning it uses characters between 127 and 255. Those characters have the eighth (i.e. the most significant) bit set. When ASP.NET reads the textfile it assumes UTF-8 encoding, and that most significant bit has a special meaning.

You must force ASP.NET to interpret the textfile as high-ANSI encoding, by telling it the codepage is 1252:

String textFilePhysicalPath = System.Web.HttpContext.Current.Server.MapPath("~/textfiles/MyInputFile.txt");
String contents = File.ReadAllText(textFilePhysicalPath, System.Text.Encoding.GetEncoding(1252));
lblContents.Text = contents.Replace("\n", "<br />");  // change linebreaks to HTML

vi/vim editor, copy a block (not usual action)

It sounds like you want to place marks in the file.

mx places a mark named x under the cursor

y'x yanks everything between the cursor's current position and the line containing mark x.

You can use 'x to simply move the cursor to the line with your mark.

You can use `x (a back-tick) to move to the exact location of the mark.


One thing I do all the time is yank everything between the cursor and mark x into the clipboard.

You can do that like this:

"+y'x

NOTE: In some environments the clipboard buffer is represented by a * in stead of a +.


Similar questions with some good answers:

How to terminate script execution when debugging in Google Chrome?

In Chrome, there is "Task Manager", accessible via Shift+ESC or through

Menu → More Tools → Task Manager

You can select your page task and end it by pressing "End Process" button.

What size do you use for varchar(MAX) in your parameter declaration?

If you do something like this:

    cmd.Parameters.Add("@blah",SqlDbType.VarChar).Value = "some large text";

size will be taken from "some large text".Length

This can be problematic when it's an output parameter, you get back no more characters then you put as input.

python convert list to dictionary

Not sure whether it would help you or not but it works to me:

l = ["a", "b", "c", "d", "e"]
outRes = dict((l[i], l[i+1]) if i+1 < len(l) else (l[i], '') for i in xrange(len(l)))

SVN Error: Commit blocked by pre-commit hook (exit code 1) with output: Error: n/a (6)

If you are getting following exception:

Error: Commit failed (details follow):
Error: Commit blocked by pre-commit hook (exit code 1) with output:
Error: svnlook: Path 'trunk/Development/ProjectName' is not a file

Then first check-in all the the directories and then all the files. It will work.

Example of Mockito's argumentCaptor

I agree with what @fge said, more over. Lets look at example. Consider you have a method:

class A {
    public void foo(OtherClass other) {
        SomeData data = new SomeData("Some inner data");
        other.doSomething(data);
    }
}

Now if you want to check the inner data you can use the captor:

// Create a mock of the OtherClass
OtherClass other = mock(OtherClass.class);

// Run the foo method with the mock
new A().foo(other);

// Capture the argument of the doSomething function
ArgumentCaptor<SomeData> captor = ArgumentCaptor.forClass(SomeData.class);
verify(other, times(1)).doSomething(captor.capture());

// Assert the argument
SomeData actual = captor.getValue();
assertEquals("Some inner data", actual.innerData);

How can I apply styles to multiple classes at once?

.abc, .xyz { margin-left: 20px; }

is what you are looking for.

fatal error LNK1169: one or more multiply defined symbols found in game programming

The two int variables are defined in the header file. This means that every source file which includes the header will contain their definition (header inclusion is purely textual). The of course leads to multiple definition errors.

You have several options to fix this.

  1. Make the variables static (static int WIDTH = 1024;). They will still exist in each source file, but their definitions will not be visible outside of the source file.

  2. Turn their definitions into declarations by using extern (extern int WIDTH;) and put the definition into one source file: int WIDTH = 1024;.

  3. Probably the best option: make the variables const (const int WIDTH = 1024;). This makes them static implicitly, and also allows them to be used as compile-time constants, allowing the compiler to use their value directly instead of issuing code to read it from the variable etc.

builder for HashMap

This is similar to the accepted answer, but a little cleaner, in my view:

ImmutableMap.of("key1", val1, "key2", val2, "key3", val3);

There are several variations of the above method, and they are great for making static, unchanging, immutable maps.

How to get image height and width using java?

So unfortunately, after trying all the answers from above, I did not get them to work after tireless times of trying. So I decided to do the real hack myself and I go this to work for me. I trust it would work perfectly for you too.

I am using this simple method to get the width of an image generated by the app and yet to be upload later for verification :

Pls. take note : you would have to enable permissions in manifest for access storage.

/I made it static and put in my Global class so I can reference or access it from just one source and if there is any modification, it would all have to be done at just one place. Just maintaining a DRY concept in java. (anyway) :)/

public static int getImageWidthOrHeight(String imgFilePath) {

            Log.d("img path : "+imgFilePath);

            // Decode image size
            BitmapFactory.Options o = new BitmapFactory.Options();
            o.inJustDecodeBounds = true;
            BitmapFactory.decodeFile(imgFilePath, o);

            int width_tmp = o.outWidth, height_tmp = o.outHeight;

            Log.d("Image width : ", Integer.toString(width_tmp) );

            //you can decide to rather return height_tmp to get the height.

            return width_tmp;

}

Is there any way to kill a Thread?

This is based on thread2 -- killable threads (Python recipe)

You need to call PyThreadState_SetasyncExc(), which is only available through ctypes.

This has only been tested on Python 2.7.3, but it is likely to work with other recent 2.x releases.

import ctypes

def terminate_thread(thread):
    """Terminates a python thread from another thread.

    :param thread: a threading.Thread instance
    """
    if not thread.isAlive():
        return

    exc = ctypes.py_object(SystemExit)
    res = ctypes.pythonapi.PyThreadState_SetAsyncExc(
        ctypes.c_long(thread.ident), exc)
    if res == 0:
        raise ValueError("nonexistent thread id")
    elif res > 1:
        # """if it returns a number greater than one, you're in trouble,
        # and you should call it again with exc=NULL to revert the effect"""
        ctypes.pythonapi.PyThreadState_SetAsyncExc(thread.ident, None)
        raise SystemError("PyThreadState_SetAsyncExc failed")

How to read the content of a file to a string in C?

// Assumes the file exists and will seg. fault otherwise.
const GLchar *load_shader_source(char *filename) {
  FILE *file = fopen(filename, "r");             // open 
  fseek(file, 0L, SEEK_END);                     // find the end
  size_t size = ftell(file);                     // get the size in bytes
  GLchar *shaderSource = calloc(1, size);        // allocate enough bytes
  rewind(file);                                  // go back to file beginning
  fread(shaderSource, size, sizeof(char), file); // read each char into ourblock
  fclose(file);                                  // close the stream
  return shaderSource;
}

This is a pretty crude solution because nothing is checked against null.

How to output numbers with leading zeros in JavaScript?

From https://gist.github.com/1180489

function pad(a, b){
  return(1e15 + a + '').slice(-b);
}

With comments:

function pad(
  a, // the number to convert 
  b // number of resulting characters
){
  return (
    1e15 + a + // combine with large number
    "" // convert to string
  ).slice(-b) // cut leading "1"
}

How to query all the GraphQL type fields without writing a long query?

Yes, you can do this using introspection. Make a GraphQL query like (for type UserType)

{
   __type(name:"UserType") {
      fields {
         name
         description
      }  
   }
}

and you'll get a response like (actual field names will depend on your actual schema/type definition)

{
  "data": {
    "__type": {
      "fields": [
        {
          "name": "id",
          "description": ""
        },
        {
          "name": "username",
          "description": "Required. 150 characters or fewer. Letters, digits and @/./+/-/_ only."
        },
        {
          "name": "firstName",
          "description": ""
        },
        {
          "name": "lastName",
          "description": ""
        },
        {
         "name": "email",
          "description": ""
        },
        ( etc. etc. ...)
      ]
    }
  }
}

You can then read this list of fields in your client and dynamically build a second GraphQL query to get all of these fields.

This relies on you knowing the name of the type that you want to get the fields for -- if you don't know the type, you could get all the types and fields together using introspection like

{
  __schema {
    types {
      name
      fields {
        name
        description
      }
    }
  }
}

NOTE: this is the over-the-wire GraphQL data -- you're on your own to figure out how to read and write with your actual client. Your graphQL javascript library may already employ introspection in some capacity, for example the apollo codegen command uses introspection to generate types.

Implement an input with a mask

You can achieve this also by using JavaScripts's native method. Its pretty simple and doesn't require any extra library to import.

<input type="text" name="date" placeholder="yyyy-mm-dd" onkeyup="
  var date = this.value;
  if (date.match(/^\d{4}$/) !== null) {
     this.value = date + '-';
  } else if (date.match(/^\d{4}\-\d{2}$/) !== null) {
     this.value = date + '-';
  }" maxlength="10">

How to check if a subclass is an instance of a class at runtime?

Class.isAssignableFrom() - works for interfaces as well. If you don't want that, you'll have to call getSuperclass() and test until you reach Object.

Should I use the Reply-To header when sending emails as a service to others?

You may want to consider placing the customer's name in the From header and your address in the Sender header:

From: Company A <[email protected]>
Sender: [email protected]

Most mailers will render this as "From [email protected] on behalf of Company A", which is accurate. And then a Reply-To of Company A's address won't seem out of sorts.

From RFC 5322:

The "From:" field specifies the author(s) of the message, that is, the mailbox(es) of the person(s) or system(s) responsible for the writing of the message. The "Sender:" field specifies the mailbox of the agent responsible for the actual transmission of the message. For example, if a secretary were to send a message for another person, the mailbox of the secretary would appear in the "Sender:" field and the mailbox of the actual author would appear in the "From:" field.

Select multiple columns using Entity Framework

You either want to select an anonymous type:

var dataset2 = from recordset 
               in entities.processlists 
               where recordset.ProcessName == processname 
               select new 
               {
                recordset.ServerName, 
                recordset.ProcessID, 
                recordset.Username
               };

But you cannot cast that to another type, so I guess you want something like this:

var dataset2 = from recordset 
               in entities.processlists 
               where recordset.ProcessName == processname 

               // Select new concrete type
               select new PInfo
               {
                ServerName = recordset.ServerName, 
                ProcessID = recordset.ProcessID, 
                Username = recordset.Username
               };

How to use matplotlib tight layout with Figure?

Just call fig.tight_layout() as you normally would. (pyplot is just a convenience wrapper. In most cases, you only use it to quickly generate figure and axes objects and then call their methods directly.)

There shouldn't be a difference between the QtAgg backend and the default backend (or if there is, it's a bug).

E.g.

import matplotlib.pyplot as plt

#-- In your case, you'd do something more like:
# from matplotlib.figure import Figure
# fig = Figure()
#-- ...but we want to use it interactive for a quick example, so 
#--    we'll do it this way
fig, axes = plt.subplots(nrows=4, ncols=4)

for i, ax in enumerate(axes.flat, start=1):
    ax.set_title('Test Axes {}'.format(i))
    ax.set_xlabel('X axis')
    ax.set_ylabel('Y axis')

plt.show()

Before Tight Layout

enter image description here

After Tight Layout

import matplotlib.pyplot as plt

fig, axes = plt.subplots(nrows=4, ncols=4)

for i, ax in enumerate(axes.flat, start=1):
    ax.set_title('Test Axes {}'.format(i))
    ax.set_xlabel('X axis')
    ax.set_ylabel('Y axis')

fig.tight_layout()

plt.show()

enter image description here

How do I set the version information for an existing .exe, .dll?

rcedit is relative new and works well from the command line: https://github.com/atom/rcedit

$ rcedit "path-to-exe-or-dll" --set-version-string "Comments" "This is an exe"
$ rcedit "path-to-exe-or-dll" --set-file-version "10.7"
$ rcedit "path-to-exe-or-dll" --set-product-version "10.7"

There's also an NPM module which wraps it from JavaScript and a Grunt task in case you're using Grunt.

Stacking DIVs on top of each other?

I positioned the divs slightly offset, so that you can see it at work.
HTML

<div class="outer">
  <div class="bot">BOT</div>
  <div class="top">TOP</div>
</div>

CSS

.outer {
  position: relative;
  margin-top: 20px;
}

.top {
  position: absolute;
  margin-top: -10px;
  background-color: green;
}

.bot {
  position: absolute;
  background-color: yellow;
}

https://codepen.io/anon/pen/EXxKzP

How to duplicate a whole line in Vim?

If you want another way:

"ayy: This will store the line in buffer a.

"ap: This will put the contents of buffer a at the cursor.

There are many variations on this.

"a5yy: This will store the 5 lines in buffer a.

See "Vim help files for more fun.

Change the On/Off text of a toggle button Android

In the example you link to, they are changing it to Day/Night by using android:textOn and android:textOff

How can I find the number of arguments of a Python function?

In:

import inspect 

class X:
    def xyz(self, a, b, c): 
        return 

print(len(inspect.getfullargspec(X.xyz).args))

Out:

4


Note: If xyz wasn't inside class X and had no "self" and just "a, b, c", then it would have printed 3.

For python below 3.5, you may want to replace inspect.getfullargspec by inspect.getargspec in the code above.

In LINQ, select all values of property X where X != null

You can use the OfType operator. It ignores null values in the source sequence. Just use the same type as MyProperty and it won't filter out anything else.

// given:
// public T MyProperty { get; }
var nonNullItems = list.Select(x => x.MyProperty).OfType<T>();

I would advise against this though. If you want to pick non-null values, what can be more explicit than saying you want "the MyProperties from the list that are not null"?

How to vertically align text with icon font?

Add this to your CSS:

.menu i.large.icon,
.menu i.large.basic.icon {
    vertical-align:baseline;
}

DEMO

htaccess remove index.php from url

try this, it work for me

_x000D_
_x000D_
<IfModule mod_rewrite.c>

# Enable Rewrite Engine
# ------------------------------
RewriteEngine On
RewriteBase /

# Redirect index.php Requests
# ------------------------------
RewriteCond %{THE_REQUEST} ^GET.*index\.php [NC]
RewriteCond %{THE_REQUEST} !/system/.*
RewriteRule (.*?)index\.php/*(.*) /$1$2 [R=301,L]

# Standard ExpressionEngine Rewrite
# ------------------------------
RewriteCond $1 !\.(css|js|gif|jpe?g|png) [NC]
RewriteCond %{REQUEST_FILENAME} !-f
RewriteCond %{REQUEST_FILENAME} !-d
RewriteRule ^(.*)$ /index.php/$1 [L]

</IfModule>
_x000D_
_x000D_
_x000D_

How to rename a component in Angular CLI?

I personally have not found any command for the same. Just make a new component (renamed name) and copy paste the previous component's html, css, and ts. In ts obviously the class name would be replaced. Its the safest method but does take a little time.

Google MAP API v3: Center & Zoom on displayed markers

I've also find this fix that zooms to fit all markers

LatLngList: an array of instances of latLng, for example:

// "map" is an instance of GMap3

var LatLngList = [
                     new google.maps.LatLng (52.537,-2.061), 
                     new google.maps.LatLng (52.564,-2.017)
                 ],
    latlngbounds = new google.maps.LatLngBounds();

LatLngList.forEach(function(latLng){
   latlngbounds.extend(latLng);
});

// or with ES6:
// for( var latLng of LatLngList)
//    latlngbounds.extend(latLng);

map.setCenter(latlngbounds.getCenter());
map.fitBounds(latlngbounds); 

How to add 30 minutes to a JavaScript Date object?

Other solution:

var dateAv = new Date();
var endTime = new Date(dateAv.getFullYear(), dateAv.getMonth(), dateAv.getDate(), dateAv.getHours(), dateAv.getMinutes() + 30);
          

How to pass a type as a method parameter in Java

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

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

The Output

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

The Code

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

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

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

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

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

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

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

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

MongoDB running but can't connect using shell

After starting the mongod

$mongod --dbpath <db name>

to get shell

$mongo --shell

How to send Request payload to REST API in java?

The following code works for me.

//escape the double quotes in json string
String payload="{\"jsonrpc\":\"2.0\",\"method\":\"changeDetail\",\"params\":[{\"id\":11376}],\"id\":2}";
String requestUrl="https://git.eclipse.org/r/gerrit/rpc/ChangeDetailService";
sendPostRequest(requestUrl, payload);

method implementation:

public static String sendPostRequest(String requestUrl, String payload) {
    try {
        URL url = new URL(requestUrl);
        HttpURLConnection connection = (HttpURLConnection) url.openConnection();

        connection.setDoInput(true);
        connection.setDoOutput(true);
        connection.setRequestMethod("POST");
        connection.setRequestProperty("Accept", "application/json");
        connection.setRequestProperty("Content-Type", "application/json; charset=UTF-8");
        OutputStreamWriter writer = new OutputStreamWriter(connection.getOutputStream(), "UTF-8");
        writer.write(payload);
        writer.close();
        BufferedReader br = new BufferedReader(new InputStreamReader(connection.getInputStream()));
        StringBuffer jsonString = new StringBuffer();
        String line;
        while ((line = br.readLine()) != null) {
                jsonString.append(line);
        }
        br.close();
        connection.disconnect();
        return jsonString.toString();
    } catch (Exception e) {
            throw new RuntimeException(e.getMessage());
    }

}

node.js + mysql connection pooling

i always use connection.relase(); after pool.getconnetion like

pool.getConnection(function (err, connection) {
      connection.release();
        if (!err)
        {
            console.log('*** Mysql Connection established with ', config.database, ' and connected as id ' + connection.threadId);
            //CHECKING USERNAME EXISTENCE
            email = receivedValues.email
            connection.query('SELECT * FROM users WHERE email = ?', [email],
                function (err, rows) {
                    if (!err)
                    {
                        if (rows.length == 1)
                        {
                            if (bcrypt.compareSync(req.body.password, rows[0].password))
                            {
                                var alldata = rows;
                                var userid = rows[0].id;
                                var tokendata = (receivedValues, userid);
                                var token = jwt.sign(receivedValues, config.secret, {
                                    expiresIn: 1440 * 60 * 30 // expires in 1440 minutes
                                });
                                console.log("*** Authorised User");
                                res.json({
                                    "code": 200,
                                    "status": "Success",
                                    "token": token,
                                    "userData": alldata,
                                    "message": "Authorised User!"
                                });
                                logger.info('url=', URL.url, 'Responce=', 'User Signin, username', req.body.email, 'User Id=', rows[0].id);
                                return;
                            }
                            else
                            {
                                console.log("*** Redirecting: Unauthorised User");
                                res.json({"code": 200, "status": "Fail", "message": "Unauthorised User!"});
                                logger.error('*** Redirecting: Unauthorised User');
                                return;
                            }
                        }
                        else
                        {
                            console.error("*** Redirecting: No User found with provided name");
                            res.json({
                                "code": 200,
                                "status": "Error",
                                "message": "No User found with provided name"
                            });
                            logger.error('url=', URL.url, 'No User found with provided name');
                            return;
                        }
                    }
                    else
                    {
                        console.log("*** Redirecting: Error for selecting user");
                        res.json({"code": 200, "status": "Error", "message": "Error for selecting user"});
                        logger.error('url=', URL.url, 'Error for selecting user', req.body.email);
                        return;
                    }
                });
            connection.on('error', function (err) {
                console.log('*** Redirecting: Error Creating User...');
                res.json({"code": 200, "status": "Error", "message": "Error Checking Username Duplicate"});
                return;
            });
        }
        else
        {
            Errors.Connection_Error(res);
        }
    });

In Rails, how do you render JSON using a view?

This is potentially a better option and faster than ERB: https://github.com/dewski/json_builder

Change color of PNG image via CSS?

The simplest one line that worked for me:

filter: opacity(0.5) drop-shadow(0 0 0 blue);

You can adjust opacity from 0 to 1 to make color lighter or darker.

The PowerShell -and conditional operator

The code that you have shown will do what you want iff those properties equal "" when they are not filled in. If they equal $null when not filled in for example, then they will not equal "". Here is an example to prove the point that what you have will work for "":

$foo = 1
$bar = 1
$foo -eq 1 -and $bar -eq 1
True
$foo -eq 1 -and $bar -eq 2
False

Program to find largest and smallest among 5 numbers without using array

Works for any number of numbers taken from standard input:

#include <algorithm>
#include <iterator>
#include <iostream>

int main()
{
    std::istream_iterator<int> it_begin(std::cin), it_end;
    auto p = std::minmax_element(it_begin, it_end);
    if (p.first != it_end)
        std::cout << "min: " << *p.first << " max: " << *p.second;
}

Disclaimer:
Technicaly, this isn't required to work by C++ standard. The minimum iterator category required for minmax_element is ForwardIterator which stream iterators are not. Once an input iterator is dereferenced or incremented, its copies are no longer guaranteed to be dereferenceable or comparable to other iterators. It Works On My MachineTM. :)

Do AJAX requests retain PHP Session info?

One thing to watch out for though, particularly if you are using a framework, is to check if the application is regenerating session ids between requests - anything that depends explicitly on the session id will run into problems, although obviously the rest of the data in the session will unaffected.

If the application is regenerating session ids like this then you can end up with a situation where an ajax request in effect invalidates / replaces the session id in the requesting page.

How to Check if value exists in a MySQL database

I tried to d this for a while and $sqlcommand = 'SELECT * FROM database WHERE search="'.$searchString.'";';
$sth = $db->prepare($sqlcommand); $sth->execute(); $record = $sth->fetch(); if ($sth->fetchColumn() > 0){}
just works if there are TWO identical entries, but, if you replace if ($sth->fetchColumn() > 0){} with if ($result){} it works with only one matching record, hope this helps.

How to check if a value is not null and not empty string in JS

Both null and empty could be validated as follows:

<script>
function getName(){
    var myname = document.getElementById("Name").value;
    if(myname != '' && myname != null){
        alert("My name is "+myname);
    }else{
        alert("Please Enter Your Name");
    }       
}

Ascending and Descending Number Order in java

You can sort the array first, and then loop through it twice, once in both directions:

Arrays.sort(arr); 
System.out.print("Numbers in Ascending Order:" ); 
for(int i = 0; i < arr.length; i++){ 
  System.out.print( " " + arr[i]); 
} 
System.out.print("Numbers in Descending Order: " ); 
for(int i = arr.length - 1; i >= 0; i--){ 
  System.out.print( " " + arr[i]); 
} 

How to connect to remote Redis server?

One thing that confused me a little bit with this command is that if redis-cli fails to connect using the passed connection string it will still put you in the redis-cli shell, i.e:

redis-cli
Could not connect to Redis at 127.0.0.1:6379: Connection refused
not connected> 

You'll then need to exit to get yourself out of the shell. I wasn't paying much attention here and kept passing in new redis-cli commands wondering why the command wasn't using my passed connection string.

How to use select/option/NgFor on an array of objects in Angular2

I don't know what things were like in the alpha, but I'm using beta 12 right now and this works fine. If you have an array of objects, create a select like this:

<select [(ngModel)]="simpleValue"> // value is a string or number
    <option *ngFor="let obj of objArray" [value]="obj.value">{{obj.name}}</option>
</select>

If you want to match on the actual object, I'd do it like this:

<select [(ngModel)]="objValue"> // value is an object
    <option *ngFor="let obj of objArray" [ngValue]="obj">{{obj.name}}</option>
</select>

Set Windows process (or user) memory limit

No way to do this that I know of, although I'm very curious to read if anyone has a good answer. I have been thinking about adding something like this to one of the apps my company builds, but have found no good way to do it.

The one thing I can think of (although not directly on point) is that I believe you can limit the total memory usage for a COM+ application in Windows. It would require the app to be written to run in COM+, of course, but it's the closest way I know of.

The working set stuff is good (Job Objects also control working sets), but that's not total memory usage, only real memory usage (paged in) at any one time. It may work for what you want, but afaik it doesn't limit total allocated memory.

TSQL - Cast string to integer or return default value

As has been mentioned, you may run into several issues if you use ISNUMERIC:

-- Incorrectly gives 0:
SELECT CASE WHEN ISNUMERIC('-') = 1 THEN CAST('-' AS INT) END   

-- Error (conversion failure):
SELECT CASE WHEN ISNUMERIC('$') = 1 THEN CAST('$' AS INT) END
SELECT CASE WHEN ISNUMERIC('4.4') = 1 THEN CAST('4.4' AS INT) END
SELECT CASE WHEN ISNUMERIC('1,300') = 1 THEN CAST('1,300' AS INT) END

-- Error (overflow):
SELECT CASE WHEN ISNUMERIC('9999999999') = 1 THEN CAST('9999999999' AS INT) END

If you want a reliable conversion, you'll need to code one yourself.

Update: My new recommendation would be to use an intermediary test conversion to FLOAT to validate the number. This approach is based on adrianm's comment. The logic can be defined as an inline table-valued function:

CREATE FUNCTION TryConvertInt (@text NVARCHAR(MAX)) 
RETURNS TABLE
AS
RETURN
(
    SELECT
        CASE WHEN ISNUMERIC(@text + '.e0') = 1 THEN 
             CASE WHEN CONVERT(FLOAT, @text) BETWEEN -2147483648 AND 2147483647 
                  THEN CONVERT(INT, @text) 
             END 
         END AS [Result]
)

Some tests:

SELECT [Conversion].[Result]
FROM ( VALUES
     ( '1234'                     )   -- 1234
   , ( '1,234'                    )   -- NULL
   , ( '1234.0'                   )   -- NULL
   , ( '-1234'                    )   -- -1234
   , ( '$1234'                    )   -- NULL
   , ( '1234e10'                  )   -- NULL
   , ( '1234 5678'                )   -- NULL
   , ( '123-456'                  )   -- NULL
   , ( '1234.5'                   )   -- NULL
   , ( '123456789000000'          )   -- NULL
   , ( 'N/A'                      )   -- NULL
   , ( '-'                        )   -- NULL
   , ( '$'                        )   -- NULL
   , ( '4.4'                      )   -- NULL
   , ( '1,300'                    )   -- NULL
   , ( '9999999999'               )   -- NULL
   , ( '00000000000000001234'     )   -- 1234
   , ( '212110090000000235698741' )   -- NULL
) AS [Source] ([Text])
OUTER APPLY TryConvertInt ([Source].[Text]) AS [Conversion]

Results are similar to Joseph Sturtevant's answer, with the following main differences:

  • My logic does not tolerate occurrences of . or , in order to mimic the behaviour of native INT conversions. '1,234' and '1234.0' return NULL.
  • Since it does not use local variables, my function can be defined as an inline table-valued function, allowing for better query optimization.
  • Joseph's answer can lead to incorrect results due to silent truncations of the argument; '00000000000000001234' evaluates to 12. Increasing the parameter length would result in errors on numbers that overflow BIGINT, such as BBANs (basic bank account numbers) like '212110090000000235698741'.

Withdrawn: The approach below is no longer recommended, as is left just for reference.

The snippet below works on non-negative integers. It checks that your string does not contain any non-digit characters, is not empty, and does not overflow (by exceeding the maximum value for the int type). However, it also gives NULL for valid integers whose length exceeds 10 characters due to leading zeros.

SELECT 
    CASE WHEN @text NOT LIKE '%[^0-9]%' THEN
         CASE WHEN LEN(@text) BETWEEN 1 AND 9 
                OR LEN(@text) = 10 AND @text <= '2147483647' 
              THEN CAST (@text AS INT)
         END
    END 

If you want to support any number of leading zeros, use the below. The nested CASE statements, albeit unwieldy, are required to promote short-circuit evaluation and reduce the likelihood of errors (arising, for example, from passing a negative length to LEFT).

SELECT 
    CASE WHEN @text NOT LIKE '%[^0-9]%' THEN
         CASE WHEN LEN(@text) BETWEEN 1 AND 9 THEN CAST (@text AS INT)
              WHEN LEN(@text) >= 10 THEN
              CASE WHEN LEFT(@text, LEN(@text) - 10) NOT LIKE '%[^0]%'
                    AND RIGHT(@text, 10) <= '2147483647'
                   THEN CAST (@text AS INT)
              END
         END
    END

If you want to support positive and negative integers with any number of leading zeros:

SELECT 
         -- Positive integers (or 0):
    CASE WHEN @text NOT LIKE '%[^0-9]%' THEN
         CASE WHEN LEN(@text) BETWEEN 1 AND 9 THEN CAST (@text AS INT)
              WHEN LEN(@text) >= 10 THEN
              CASE WHEN LEFT(@text, LEN(@text) - 10) NOT LIKE '%[^0]%'
                    AND RIGHT(@text, 10) <= '2147483647'
                   THEN CAST (@text AS INT)
              END
         END
         -- Negative integers:
         WHEN LEFT(@text, 1) = '-' THEN
         CASE WHEN RIGHT(@text, LEN(@text) - 1) NOT LIKE '%[^0-9]%' THEN
              CASE WHEN LEN(@text) BETWEEN 2 AND 10 THEN CAST (@text AS INT)
                   WHEN LEN(@text) >= 11 THEN
                   CASE WHEN SUBSTRING(@text, 2, LEN(@text) - 11) NOT LIKE '%[^0]%'
                         AND RIGHT(@text, 10) <= '2147483648'
                        THEN CAST (@text AS INT)
                   END
              END
         END
    END

log4j vs logback

Your decision should be based on

  • your actual need for these "more features"; and
  • your expected cost of implementing the change.

You should resist the urge to change APIs just because it's "newer, shinier, better." I follow a policy of "if it's not broken, don't kick it."

If your application requires a very sophisticated logging framework, you may want to consider why.

How to set cursor position in EditText?

I believe the most simple way to do this is just use padding.

Say in your xml's edittext section, add android:paddingLeft="100dp" This will move your start position of cursor 100dp right from left end.

Same way, you can use android:paddingRight="100dp" This will move your end position of cursor 100dp left from right end.

For more detail, check this article on my blog: Android: Setting Cursor Starting and Ending Position in EditText Widget

Pass variables from servlet to jsp

You could set all the values into the response object before forwaring the request to the jsp. Or you can put your values into a session bean and access it in the jsp.

Getting session value in javascript

You can access your session variable like '<%= Session["VariableName"]%>'

the text in single quotes will give session value. 1)

<script>
var session ='<%= Session["VariableName"]%>'
</script>

2) you can take a hidden field and assign value at server;

hiddenfield.value= session["xyz"].tostring();

//and in script you access the hiddenfield  like

alert(document.getElementbyId("hiddenfield").value);

document.getelementbyId will return null if element is not defined?

Yes it will return null if it's not present you can try this below in the demo. Both will return true. The first elements exists the second doesn't.

Demo

Html

<div id="xx"></div>

Javascript:

   if (document.getElementById('xx') !=null) 
     console.log('it exists!');

   if (document.getElementById('xxThisisNotAnElementOnThePage') ==null) 
     console.log('does not exist!');

Scroll to bottom of div with Vue.js

I tried the accepted solution and it didn't work for me. I use the browser debugger and found out the actual height that should be used is the clientHeight BUT you have to put this into the updated() hook for the whole solution to work.

data(){
return {
  conversation: [
    {
    }
  ]
 },
mounted(){
 EventBus.$on('msg-ctr--push-msg-in-conversation', textMsg => {
  this.conversation.push(textMsg)
  // Didn't work doing scroll here
 })
},
updated(){              <=== PUT IT HERE !!
  var elem = this.$el
  elem.scrollTop = elem.clientHeight;
},

How to execute two mysql queries as one in PHP/MYSQL?

Update: Apparently possible by passing a flag to mysql_connect(). See Executing multiple SQL queries in one statement with PHP Nevertheless, any current reader should avoid using the mysql_-class of functions and prefer PDO.

You can't do that using the regular mysql-api in PHP. Just execute two queries. The second one will be so fast that it won't matter. This is a typical example of micro optimization. Don't worry about it.

For the record, it can be done using mysqli and the mysqli_multi_query-function.

Server.Transfer Vs. Response.Redirect

Just more details about Transfer(), it's actually is Server.Execute() + Response.End(), its source code is below (from Mono/.net 4.0):

public void Transfer (string path, bool preserveForm)
{
    this.Execute (path, null, preserveForm, true);
    this.context.Response.End ();
}

and for Execute(), what it is to run is the handler of the given path, see

ASP.NET does not verify that the current user is authorized to view the resource delivered by the Execute method. Although the ASP.NET authorization and authentication logic runs before the original resource handler is called, ASP.NET directly calls the handler indicated by the Execute method and does not rerun authentication and authorization logic for the new resource. If your application's security policy requires clients to have appropriate authorization to access the resource, the application should force reauthorization or provide a custom access-control mechanism.

You can force reauthorization by using the Redirect method instead of the Execute method. Redirect performs a client-side redirect in which the browser requests the new resource. Because this redirect is a new request entering the system, it is subjected to all the authentication and authorization logic of both Internet Information Services (IIS) and ASP.NET security policy.

-from MSDN

How set maximum date in datepicker dialog in android?

      Calendar cal = Calendar.getInstance();
      datePickerDialog.getDatePicker().setMinDate(cal.getTimeInMillis());
    //To set make max 7days date selection on current year and month
    datePickerDialog.getDatePicker().setMaxDate((cal.getTimeInMillis())+(1000*60*60*24*6));

    datePickerDialog.setTitle("Select Date");
    datePickerDialog.show();

Convert to binary and keep leading zeros in Python

You can use zfill:

print str(1).zfill(2) 
print str(10).zfill(2) 
print str(100).zfill(2)

prints:

01
10
100

I like this solution, as it helps not only when outputting the number, but when you need to assign it to a variable... e.g. - x = str(datetime.date.today().month).zfill(2) will return x as '02' for the month of feb.

How do you do dynamic / dependent drop downs in Google Sheets?

You can start with a google sheet set up with a main page and drop down source page like shown below.

You can set up the first column drop down through the normal Data > Validations menu prompts.

Main Page

Main Page with the drop down for the first column already populated.

Drop Down Source Page

Source page for all of the sub-categories needed

After that, you need to set up a script with the name onEdit. (If you don't use that name, the getActiveRange() will do nothing but return cell A1)

And use the code provided here:

function onEdit() {
  var ss = SpreadsheetApp.getActiveSpreadsheet();
  var sheet = SpreadsheetApp.getActiveSheet();
  var myRange = SpreadsheetApp.getActiveRange();
  var dvSheet = SpreadsheetApp.getActiveSpreadsheet().getSheetByName("Categories");
  var option = new Array();
  var startCol = 0;

  if(sheet.getName() == "Front Page" && myRange.getColumn() == 1 && myRange.getRow() > 1){
    if(myRange.getValue() == "Category 1"){
      startCol = 1;
    } else if(myRange.getValue() == "Category 2"){
      startCol = 2;
    } else if(myRange.getValue() == "Category 3"){
      startCol = 3;
    } else if(myRange.getValue() == "Category 4"){
      startCol = 4;
    } else {
      startCol = 10
    }

  if(startCol > 0 && startCol < 10){
    option = dvSheet.getSheetValues(3,startCol,10,1);
    var dv = SpreadsheetApp.newDataValidation();
    dv.setAllowInvalid(false);  
    //dv.setHelpText("Some help text here");
    dv.requireValueInList(option, true);
    sheet.getRange(myRange.getRow(),myRange.getColumn() + 1).setDataValidation(dv.build());
   }

  if(startCol == 10){
    sheet.getRange(myRange.getRow(),myRange.getColumn() + 1).clearDataValidations();
  } 
  }
}

After that, set up a trigger in the script editor screen by going to Edit > Current Project Triggers. This will bring up a window to have you select various drop downs to eventually end up at this:

Trigger set up

You should be good to go after that!

Split string using a newline delimiter with Python

If you want to split only by newlines, you can use str.splitlines():

Example:

>>> data = """a,b,c
... d,e,f
... g,h,i
... j,k,l"""
>>> data
'a,b,c\nd,e,f\ng,h,i\nj,k,l'
>>> data.splitlines()
['a,b,c', 'd,e,f', 'g,h,i', 'j,k,l']

With str.split() your case also works:

>>> data = """a,b,c
... d,e,f
... g,h,i
... j,k,l"""
>>> data
'a,b,c\nd,e,f\ng,h,i\nj,k,l'
>>> data.split()
['a,b,c', 'd,e,f', 'g,h,i', 'j,k,l']

However if you have spaces (or tabs) it will fail:

>>> data = """
... a, eqw, qwe
... v, ewr, err
... """
>>> data
'\na, eqw, qwe\nv, ewr, err\n'
>>> data.split()
['a,', 'eqw,', 'qwe', 'v,', 'ewr,', 'err']

Handlebars.js Else If

Handlebars now supports {{else if}} as of 3.0.0. Therefore, your code should now work.

You can see an example under "conditionals" (slightly revised here with an added {{else}}:

    {{#if isActive}}
      <img src="star.gif" alt="Active">
    {{else if isInactive}}
      <img src="cry.gif" alt="Inactive">
    {{else}}
      <img src="default.gif" alt="default">
    {{/if}}

http://handlebarsjs.com/block_helpers.html

Format a JavaScript string using placeholders and an object of substitutions?

You can use a custom replace function like this:

var str = "My Name is %NAME% and my age is %AGE%.";
var replaceData = {"%NAME%":"Mike","%AGE%":"26","%EVENT%":"20"};

function substitute(str, data) {
    var output = str.replace(/%[^%]+%/g, function(match) {
        if (match in data) {
            return(data[match]);
        } else {
            return("");
        }
    });
    return(output);
}

var output = substitute(str, replaceData);

You can see it work here: http://jsfiddle.net/jfriend00/DyCwk/.

How to set the font style to bold, italic and underlined in an Android TextView?

This is an easy way to add an underline, while maintaining other settings:

textView.setPaintFlags(textView.getPaintFlags() | Paint.UNDERLINE_TEXT_FLAG);

Pandas count(distinct) equivalent

Here is another method, much simple, lets say your dataframe name is daat and column name is YEARMONTH

daat.YEARMONTH.value_counts()

Difference between virtual and abstract methods

First of all you should know the difference between a virtual and abstract method.

Abstract Method

  • Abstract Method resides in abstract class and it has no body.
  • Abstract Method must be overridden in non-abstract child class.

Virtual Method

  • Virtual Method can reside in abstract and non-abstract class.
  • It is not necessary to override virtual method in derived but it can be.
  • Virtual method must have body ....can be overridden by "override keyword".....

How do I obtain a list of all schemas in a Sql Server database

If you are using Sql Server Management Studio, you can obtain a list of all schemas, create your own schema or remove an existing one by browsing to:

Databases - [Your Database] - Security - Schemas

[

HTML inside Twitter Bootstrap popover

This is an old question, but this is another way, using jQuery to reuse the popover and to keep using the original bootstrap data attributes to make it more semantic:

The link

<a href="#" rel="popover" data-trigger="focus" data-popover-content="#popover">
   Show it!
</a>

Custom content to show

<!-- Let's show the Bootstrap nav on the popover-->
<div id="list-popover" class="hide">
    <ul class="nav nav-pills nav-stacked">
        <li><a href="#">Action</a></li>
        <li><a href="#">Another action</a></li>
        <li><a href="#">Something else here</a></li>
        <li><a href="#">Separated link</a></li>
    </ul>
</div>

Javascript

$('[rel="popover"]').popover({
    container: 'body',
    html: true,
    content: function () {
        var clone = $($(this).data('popover-content')).clone(true).removeClass('hide');
        return clone;
    }
});

Fiddle with complete example: http://jsfiddle.net/tomsarduy/262w45L5/

What is the best/simplest way to read in an XML file in Java application?

There are of course a lot of good solutions based on what you need. If it is just configuration, you should have a look at Jakarta commons-configuration and commons-digester.

You could always use the standard JDK method of getting a document :

import java.io.File;
import javax.xml.parsers.DocumentBuilder;
import javax.xml.parsers.DocumentBuilderFactory;
import org.w3c.dom.Document;

[...]

File file = new File("some/path");
DocumentBuilderFactory dbf = DocumentBuilderFactory.newInstance();
DocumentBuilder db = dbf.newDocumentBuilder();
Document document = db.parse(file);

View's SELECT contains a subquery in the FROM clause

Looks to me as MySQL 3.6 gives the following error while MySQL 3.7 no longer errors out. I am yet to find anything in the documentation regarding this fix.

SQL-Server: Is there a SQL script that I can use to determine the progress of a SQL Server backup or restore process?

Try wih :

SELECT * FROM sys.dm_exec_requests where command like '%BACKUP%'

SELECT command, percent_complete, start_time FROM sys.dm_exec_requests where command like '%BACKUP%'

SELECT command, percent_complete,total_elapsed_time, estimated_completion_time, start_time
  FROM sys.dm_exec_requests
  WHERE command IN ('RESTORE DATABASE','BACKUP DATABASE')

Java Interfaces/Implementation naming convention

I've seen answers here that suggest that if you only have one implementation then you don't need an interface. This flies in the face of the Depencency Injection/Inversion of Control principle (don't call us, we'll call you!).

So yes, there are situations in which you wish to simplify your code and make it easily testable by relying on injected interface implementations (which may also be proxied - your code doesn't know!). Even if you only have two implementations - one a Mock for testing, and one that gets injected into the actual production code - this doesn't make having an interface superfluous. A well documented interface establishes a contract, which can also be maintained by a strict mock implementation for testing.

in fact, you can establish tests that have mocks implement the most strict interface contract (throwing exceptions for arguments that shouldn't be null, etc) and catch errors in testing, using a more efficient implementation in production code (not checking arguments that should not be null for being null since the mock threw exceptions in your tests and you know that the arguments aren't null due to fixing the code after these tests, for example).

Dependency Injection/IOC can be hard to grasp for a newcomer, but once you understand its potential you'll want to use it all over the place and you'll find yourself making interfaces all the time - even if there will only be one (actual production) implementation.

For this one implementation (you can infer, and you'd be correct, that I believe the mocks for testing should be called Mock(InterfaceName)), I prefer the name Default(InterfaceName). If a more specific implementation comes along, it can be named appropriately. This also avoids the Impl suffix that I particularly dislike (if it's not an abstract class, OF COURSE it is an "impl"!).

I also prefer "Base(InterfaceName)" as opposed to "Abstract(InterfaceName)" because there are some situations in which you want your base class to become instantiable later, but now you're stuck with the name "Abstract(InterfaceName)", and this forces you to rename the class, possibly causing a little minor confusion - but if it was always Base(InterfaceName), removing the abstract modifier doesn't change what the class was.

Difference between Math.Floor() and Math.Truncate()

Math.Floor(): Returns the largest integer less than or equal to the specified double-precision floating-point number.

Math.Round(): Rounds a value to the nearest integer or to the specified number of fractional digits.

Vue - Deep watching an array of objects and calculating the change?

Your comparison function between old value and new value is having some issue. It is better not to complicate things so much, as it will increase your debugging effort later. You should keep it simple.

The best way is to create a person-component and watch every person separately inside its own component, as shown below:

<person-component :person="person" v-for="person in people"></person-component>

Please find below a working example for watching inside person component. If you want to handle it on parent side, you may use $emit to send an event upwards, containing the id of modified person.

_x000D_
_x000D_
Vue.component('person-component', {_x000D_
    props: ["person"],_x000D_
    template: `_x000D_
        <div class="person">_x000D_
            {{person.name}}_x000D_
            <input type='text' v-model='person.age'/>_x000D_
        </div>`,_x000D_
    watch: {_x000D_
        person: {_x000D_
            handler: function(newValue) {_x000D_
                console.log("Person with ID:" + newValue.id + " modified")_x000D_
                console.log("New age: " + newValue.age)_x000D_
            },_x000D_
            deep: true_x000D_
        }_x000D_
    }_x000D_
});_x000D_
_x000D_
new Vue({_x000D_
    el: '#app',_x000D_
    data: {_x000D_
        people: [_x000D_
          {id: 0, name: 'Bob', age: 27},_x000D_
          {id: 1, name: 'Frank', age: 32},_x000D_
          {id: 2, name: 'Joe', age: 38}_x000D_
        ]_x000D_
    }_x000D_
});
_x000D_
<script src="https://unpkg.com/[email protected]/dist/vue.js"></script>_x000D_
<body>_x000D_
    <div id="app">_x000D_
        <p>List of people:</p>_x000D_
        <person-component :person="person" v-for="person in people"></person-component>_x000D_
    </div>_x000D_
</body>
_x000D_
_x000D_
_x000D_

javascript push multidimensional array

Use []:

cookie_value_add.push([productID,itemColorTitle, itemColorPath]);

or

arrayToPush.push([value1, value2, ..., valueN]);

What's the difference between emulation and simulation?

Based on software and system engineering experience, I'd summarise the difference as follows:

Simulation: for me, this is always in software - every aspect of the real system is only MODELLED by some code and/or mathematics. Simulation attempts to accurately reproduce the behaviour (or predict it) of the real system, but only approximates it.

Emulation: As opposed to simulation, it does not APPROXIMATE the behaviour of the real system, it COPIES the behaviour of the real system. An emulator may involve hardware. But it may also be entirely in software. E.g. you get these software EMULATORS for old game consoles like the Sega Genesis. That is an emulator because it COPIES the real genesis functionality so much so that you can run the original Genesis code in the emulator. A genesis simulator would not be able to run the original code, it would only APPROXIMATE its behaviour, producing similar results, depending on how good the models of the original system were.

An emulator of a system component can be included in a larger system, completely replacing the component it is emulating - a simulator could not because it is not an accurate enough representation of the original component behaviour.

Turn a simple socket into an SSL socket

Here my example ssl socket server threads (multiple connection) https://github.com/breakermind/CppLinux/blob/master/QtSslServerThreads/breakermindsslserver.cpp

#include <pthread.h>
#include <stdio.h>
#include <stdlib.h>
#include <string>
#include <unistd.h>
#include <iostream>

#include <breakermindsslserver.h>

using namespace std;

int main(int argc, char *argv[])
{
    BreakermindSslServer boom;
    boom.Start(123,"/home/user/c++/qt/BreakermindServer/certificate.crt", "/home/user/c++/qt/BreakermindServer/private.key");
    return 0;
}

What is a software framework?

I'm very late to answer it. But, I would like to share one example, which I only thought of today. If I told you to cut a piece of paper with dimensions 5m by 5m, then surely you would do that. But suppose I ask you to cut 1000 pieces of paper of the same dimensions. In this case, you won't do the measuring 1000 times; obviously, you would make a frame of 5m by 5m, and then with the help of it you would be able to cut 1000 pieces of paper in less time. So, what you did was make a framework which would do a specific type of task. Instead of performing the same type of task again and again for the same type of applications, you create a framework having all those facilities together in one nice packet, hence providing the abstraction for your application and more importantly many applications.

Jackson with JSON: Unrecognized field, not marked as ignorable

I fixed this problem by simply changing the signatures of my setter and getter methods of my POJO class. All I had to do was change the getObject method to match what the mapper was looking for. In my case I had a getImageUrl originally, but the JSON data had image_url which was throwing the mapper off. I changed both my setter and getters to getImage_url and setImage_url.

Hope this helps.

jQuery .css("margin-top", value) not updating in IE 8 (Standards mode)

Try marginTop in place of margin-top, eg:

$("#ActionBox").css("marginTop", foo);

Deleting Elements in an Array if Element is a Certain value VBA

An array is a structure with a certain size. You can use dynamic arrays in vba that you can shrink or grow using ReDim but you can't remove elements in the middle. It's not clear from your sample how your array functionally works or how you determine the index position (eachHdr) but you basically have 3 options

(A) Write a custom 'delete' function for your array like (untested)

Public Sub DeleteElementAt(Byval index As Integer, Byref prLst as Variant)
       Dim i As Integer

        ' Move all element back one position
        For i = index + 1 To UBound(prLst)
            prLst(i - 1) = prLst(i)
        Next

        ' Shrink the array by one, removing the last one
        ReDim Preserve prLst(Len(prLst) - 1)
End Sub

(B) Simply set a 'dummy' value as the value instead of actually deleting the element

If prLst(eachHdr) = "0" Then        
   prLst(eachHdr) = "n/a"
End If

(C) Stop using an array and change it into a VBA.Collection. A collection is a (unique)key/value pair structure where you can freely add or delete elements from

Dim prLst As New Collection

Visual Studio 2010 - recommended extensions

VisualHG is a Mercurial Source control plugin that drives TortoiseHG from VS. I'm a big fan of Mercurial & DVCS. VisualHG makes it nice n integrated. Git fans - I'm not asking for a flame war. Hg is just my brand.

Visual Studio loading symbols

Configure in Tools, Options, Debugging, Symbols.

You can watch the output window (view, output) to see what it's doing usually. If it's really slow that probably means it's hitting a symbol server, probably Microsoft's, to download missing symbols. This takes three HTTP hits for each file it can't find on every startup - you can sometimes see this in the status bar at the bottom or in e.g. Fiddler. You can see which modules have loaded symbols in Debug, Windows, Modules whilst you're debugging.

Symbols mean you get useful stack trace information into third party and system assemblies. You definitely need them for your own code, but I think those get loaded regardless. Your best bet is to turn off any non-local symbol sources in that menu and, if you're loading lots of symbols for system assemblies that you don't need to debug into you can temporarily disable loading those to speed up debug start - but they're often useful to have loaded.

How do I get a background location update every n minutes in my iOS application?

Attached is a Swift solution based in:

Define App registers for location updates in the info.plist

Keep the locationManager running all the time

Switch kCLLocationAccuracy between BestForNavigation (for 5 secs to get the location) and ThreeKilometers for the rest of the wait period to avoid battery drainage

This example updates location every 1 min in Foreground and every 15 mins in Background.

The example works fine with Xcode 6 Beta 6, running in a iOS 7 device.

In the App Delegate (mapView is an Optional pointing to the mapView Controller)

func applicationDidBecomeActive(application: UIApplication!) {
    if appLaunched! == false { // Reference to mapView used to limit one location update per timer cycle
        appLaunched = true
        var appDelegate = UIApplication.sharedApplication().delegate as AppDelegate
        var window = appDelegate.window
        var tabBar = window?.rootViewController as UITabBarController
        var navCon = tabBar.viewControllers[0] as UINavigationController
        mapView = navCon.topViewController as? MapViewController
    }
    self.startInitialPeriodWithTimeInterval(60.0)
}

func applicationDidEnterBackground(application: UIApplication!) {
    self.startInitialPeriodWithTimeInterval(15 * 60.0)
}

func startInitialPeriodWithTimeInterval(timeInterval: NSTimeInterval) {
    timer?.invalidate() // reset timer
    locationManager?.desiredAccuracy = kCLLocationAccuracyBestForNavigation
    timer = NSTimer.scheduledTimerWithTimeInterval(5.0, target: self, selector: Selector("getFirstLocationUpdate:"), userInfo: timeInterval, repeats: false)
}

func getFirstLocationUpdate(sender: NSTimer) {
    let timeInterval = sender.userInfo as Double
    timer?.invalidate()
    mapView?.canReportLocation = true
    timer = NSTimer.scheduledTimerWithTimeInterval(timeInterval, target: self, selector: Selector("waitForTimer:"), userInfo: timeInterval, repeats: true)
}

func waitForTimer(sender: NSTimer) {
    let time = sender.userInfo as Double
    locationManager?.desiredAccuracy = kCLLocationAccuracyBestForNavigation
    finalTimer = NSTimer.scheduledTimerWithTimeInterval(5.0, target: self, selector: Selector("getLocationUpdate"), userInfo: nil, repeats: false)
}

func getLocationUpdate() {
    finalTimer?.invalidate()
    mapView?.canReportLocation = true
}

In the mapView (locationManager points to the object in the AppDelegate)

override func viewDidLoad() {
    super.viewDidLoad()
    var appDelegate = UIApplication.sharedApplication().delegate! as AppDelegate
    locationManager = appDelegate.locationManager!
    locationManager.delegate = self
    canReportLocation = true
}

  func locationManager(manager: CLLocationManager!, didUpdateLocations locations: [AnyObject]!) {
        if canReportLocation! {
            canReportLocation = false
            locationManager.desiredAccuracy = kCLLocationAccuracyThreeKilometers
        } else {
            //println("Ignore location update")
        }
    }

Get: TypeError: 'dict_values' object does not support indexing when using python 3.2.3

In Python 3, dict.values() (along with dict.keys() and dict.items()) returns a view, rather than a list. See the documentation here. You therefore need to wrap your call to dict.values() in a call to list like so:

v = list(d.values())
{names[i]:v[i] for i in range(len(names))}

How to tell CRAN to install package dependencies automatically?

Another possibility is to select the Install Dependencies checkbox In the R package installer, on the bottom right:

enter image description here

How to display Woocommerce product price by ID number on a custom page?

In woocommerce,

Get regular price :

$price = get_post_meta( get_the_ID(), '_regular_price', true);
// $price will return regular price

Get sale price:

$sale = get_post_meta( get_the_ID(), '_sale_price', true);
// $sale will return sale price

ORA-01950: no privileges on tablespace 'USERS'

You cannot insert data because you have a quota of 0 on the tablespace. To fix this, run

ALTER USER <user> quota unlimited on <tablespace name>;

or

ALTER USER <user> quota 100M on <tablespace name>;

as a DBA user (depending on how much space you need / want to grant).

powershell is missing the terminator: "

In your script, why are you using single quotes around the variables? These will not be expanded. Use double quotes for variable expansion or just the variable names themselves.

unzipRelease –Src '$ReleaseFile' -Dst '$Destination'

to

unzipRelease –Src "$ReleaseFile" -Dst "$Destination"

jQuery get content between <div> tags

This is probably what you need:

$('div').html();

demo

This says get the div and return all the contents inside it. See more here: http://api.jquery.com/html/

If you had many divs on the page and needed to target just one, you could set an id on the div and call it like so

$('#whatever').html();

where whatever is the id

EDIT

Now that you have clarified your question re this being a string, here is a way to do it with vanilla js:

var l = x.length;
var y = x.indexOf('<div>');
var s = x.slice(y,l);
alert(s);

Demo Here

  1. get the length of the string.
  2. find out where the first div occurs
  3. slice the content there.

Moving from position A to position B slowly with animation

Use jquery animate and give it a long duration say 2000

$("#Friends").animate({ 
        top: "-=30px",
      }, duration );

The -= means that the animation will be relative to the current top position.

Note that the Friends element must have position set to relative in the css:

#Friends{position:relative;}

ActiveX component can't create object

Check your browser settings.

For me, using IE, the fix was to go into Tools/Internet Options, Security tab, for the relevant zone, "custom level" and check the ActiveX settings. Setting "Initialize and script ActiveX controls not marked as safe for scripting" to "Enable" fixed this problem for me.

How to use Scanner to accept only valid int as input

This should work:

import java.util.Scanner;

public class Test {
    public static void main(String... args) throws Throwable {
        Scanner kb = new Scanner(System.in);

        int num1;
        System.out.print("Enter number 1: ");
        while (true)
            try {
                num1 = Integer.parseInt(kb.nextLine());
                break;
            } catch (NumberFormatException nfe) {
                System.out.print("Try again: ");
            }

        int num2;
        do {
            System.out.print("Enter number 2: ");
            while (true)
                try {
                    num2 = Integer.parseInt(kb.nextLine());
                    break;
                } catch (NumberFormatException nfe) {
                    System.out.print("Try again: ");
                }
        } while (num2 < num1);

    }
}

Calling a JavaScript function returned from an Ajax response

Federico Zancan's answer is correct but you don't have to give your script an ID and eval all your script. Just eval your function name and it can be called.

To achieve this in our project, we wrote a proxy function to call the function returned inside the Ajax response.

function FunctionProxy(functionName){
    var func = eval(functionName);
    func();
}

'Class' does not contain a definition for 'Method'

I just ran into this problem; the issue seems different from the other answers posted here, so I'll mention it in case it helps someone.

In my case, I have an internal base class defined in one assembly ("A"), an internal derived class defined in a second assembly ("B"), and a test assembly ("TEST"). I exposed internals defined in assembly "B" to "TEST" using InternalsVisibleToAttribute, but neglected to do so for assembly "A". This produced the error mentioned at top with no further indication of the problem; using InternalsVisibleToAttribute to expose assembly "A" to "TEST" resolved the issue.

Visual Studio 2017 error: Unable to start program, An operation is not legal in the current state

For me, the solution (workaround) is to turn off JavaScript debugging on Chrome, which I believe is a new feature introduced in VS 2017.

Go to Tools > Options > Debugging > General and turn off the setting for Enable JavaScript Debugging for ASP.NET (Chrome and IE).

VS2017 Disable JS Debugging

This is a known issue already, and seems to have an investigation underway.

Full information about JS debugging in VS 2017 here: https://blogs.msdn.microsoft.com/webdev/2016/11/21/client-side-debugging-of-asp-net-projects-in-google-chrome/

Trying to embed newline in a variable in bash

sed solution:

echo "a b c" | sed 's/ \+/\n/g'

Result:

a
b
c

.Contains() on a list of custom class objects

By default reference types have reference equality (i.e. two instances are only equal if they are the same object).

You need to override Object.Equals (and Object.GetHashCode to match) to implement your own equality. (And it is then good practice to implement an equality, ==, operator.)

What's the best visual merge tool for Git?

gitx http://gitx.frim.nl/

Some bugs when working with large commit sets but great for browsing through changes and picking different changes to stage and then commit.

How to pass multiple checkboxes using jQuery ajax post

Here's a more flexible way.

let's say this is your form.

<form>
<input type='checkbox' name='user_ids[]' value='1'id='checkbox_1' />
<input type='checkbox' name='user_ids[]' value='2'id='checkbox_2' />
<input type='checkbox' name='user_ids[]' value='3'id='checkbox_3' />
<input name="confirm" type="button" value="confirm" onclick="submit_form();" />
</form>

And this is your jquery ajax below...

                // Don't get confused at this portion right here
                // cuz "var data" will get all the values that the form
                // has submitted in the $_POST. It doesn't matter if you 
                // try to pass a text or password or select form element.
                // Remember that the "form" is not a name attribute
                // of the form, but the "form element" itself that submitted
                // the current post method
                var data = $("form").serialize(); 

                $.ajax({
                    url: "link/of/your/ajax.php", // link of your "whatever" php
                    type: "POST",
                    async: true,
                    cache: false,
                    data: data, // all data will be passed here
                    success: function(data){ 
                        alert(data) // The data that is echoed from the ajax.php
                    }
                });

And in your ajax.php, you try echoing or print_r your post to see what's happening inside it. This should look like this. Only checkboxes that you checked will be returned. If you didn't checked any, it will return an error.

<?php 
    print_r($_POST); // this will be echoed back to you upon success.
    echo "This one too, will be echoed back to you";

Hope that is clear enough.

Multiple file extensions in OpenFileDialog

Based on First answer here is the complete image selection options:

Filter = @"|All Image Files|*.BMP;*.bmp;*.JPG;*.JPEG*.jpg;*.jpeg;*.PNG;*.png;*.GIF;*.gif;*.tif;*.tiff;*.ico;*.ICO
           |PNG|*.PNG;*.png
           |JPEG|*.JPG;*.JPEG*.jpg;*.jpeg
           |Bitmap(.BMP,.bmp)|*.BMP;*.bmp                                    
           |GIF|*.GIF;*.gif
           |TIF|*.tif;*.tiff
           |ICO|*.ico;*.ICO";

How to make a input field readonly with JavaScript?

Here you have example how to set the readonly attribute:

_x000D_
_x000D_
<form action="demo_form.asp">_x000D_
  Country: <input type="text" name="country" value="Norway" readonly><br>_x000D_
  <input type="submit" value="Submit">_x000D_
</form>
_x000D_
_x000D_
_x000D_

VIM Disable Automatic Newline At End Of File

I've implemented Blixtor's suggestions with Perl and Python post-processing, either running inside Vim (if it is compiled with such language support), or via an external Perl script. It's available as the PreserveNoEOL plugin on vim.org.

How does C compute sin() and other math functions?

Concerning trigonometric function like sin(), cos(),tan() there has been no mention, after 5 years, of an important aspect of high quality trig functions: Range reduction.

An early step in any of these functions is to reduce the angle, in radians, to a range of a 2*p interval. But p is irrational so simple reductions like x = remainder(x, 2*M_PI) introduce error as M_PI, or machine pi, is an approximation of p. So, how to do x = remainder(x, 2*p)?

Early libraries used extended precision or crafted programming to give quality results but still over a limited range of double. When a large value was requested like sin(pow(2,30)), the results were meaningless or 0.0 and maybe with an error flag set to something like TLOSS total loss of precision or PLOSS partial loss of precision.

Good range reduction of large values to an interval like -p to p is a challenging problem that rivals the challenges of the basic trig function, like sin(), itself.

A good report is Argument reduction for huge arguments: Good to the last bit (1992). It covers the issue well: discusses the need and how things were on various platforms (SPARC, PC, HP, 30+ other) and provides a solution algorithm the gives quality results for all double from -DBL_MAX to DBL_MAX.


If the original arguments are in degrees, yet may be of a large value, use fmod() first for improved precision. A good fmod() will introduce no error and so provide excellent range reduction.

// sin(degrees2radians(x))
sin(degrees2radians(fmod(x, 360.0))); // -360.0 < fmod(x,360) < +360.0

Various trig identities and remquo() offer even more improvement. Sample: sind()

What does the Excel range.Rows property really do?

I'm not sure, but I think the second parameter is a red herring.

Both .Rows and .Columns take two optional parameters: RowIndex and ColumnIndex. Try to use ColumnIndex, e.g. Rows(ColumnIndex:=2), generates an error for both .Rows and .Columns.

My feeling it's inherited in some sense from the Cells(RowIndex,ColumnIndex) Property but only the first parameter is appropriate.

Why shouldn't I use mysql_* functions in PHP?

Ease of use

The analytic and synthetic reasons were already mentioned. For newcomers there's a more significant incentive to stop using the dated mysql_ functions.

Contemporary database APIs are just easier to use.

It's mostly the bound parameters which can simplify code. And with excellent tutorials (as seen above) the transition to PDO isn't overly arduous.

Rewriting a larger code base at once however takes time. Raison d'être for this intermediate alternative:

Equivalent pdo_* functions in place of mysql_*

Using <pdo_mysql.php> you can switch from the old mysql_ functions with minimal effort. It adds pdo_ function wrappers which replace their mysql_ counterparts.

  1. Simply include_once("pdo_mysql.php"); in each invocation script that has to interact with the database.

  2. Remove the mysql_ function prefix everywhere and replace it with pdo_.

    • mysql_connect() becomes pdo_connect()
    • mysql_query() becomes pdo_query()
    • mysql_num_rows() becomes pdo_num_rows()
    • mysql_insert_id() becomes pdo_insert_id()
    • mysql_fetch_array() becomes pdo_fetch_array()
    • mysql_fetch_assoc() becomes pdo_fetch_assoc()
    • mysql_real_escape_string() becomes pdo_real_escape_string()
    • and so on...

  3. Your code will work alike and still mostly look the same:

    include_once("pdo_mysql.php"); 
    
    pdo_connect("localhost", "usrABC", "pw1234567");
    pdo_select_db("test");
    
    $result = pdo_query("SELECT title, html FROM pages");  
    
    while ($row = pdo_fetch_assoc($result)) {
        print "$row[title] - $row[html]";
    }
    

Et voilà.
Your code is using PDO.
Now it's time to actually utilize it.

Bound parameters can be easy to use

You just need a less unwieldy API.

pdo_query() adds very facile support for bound parameters. Converting old code is straightforward:

Move your variables out of the SQL string.

  • Add them as comma delimited function parameters to pdo_query().
  • Place question marks ? as placeholders where the variables were before.
  • Get rid of ' single quotes that previously enclosed string values/variables.

The advantage becomes more obvious for lengthier code.

Often string variables aren't just interpolated into SQL, but concatenated with escaping calls in between.

pdo_query("SELECT id, links, html, title, user, date FROM articles
   WHERE title='" . pdo_real_escape_string($title) . "' OR id='".
   pdo_real_escape_string($title) . "' AND user <> '" .
   pdo_real_escape_string($root) . "' ORDER BY date")

With ? placeholders applied you don't have to bother with that:

pdo_query("SELECT id, links, html, title, user, date FROM articles
   WHERE title=? OR id=? AND user<>? ORDER BY date", $title, $id, $root)

Remember that pdo_* still allows either or.
Just don't escape a variable and bind it in the same query.

  • The placeholder feature is provided by the real PDO behind it.
  • Thus also allowed :named placeholder lists later.

More importantly you can pass $_REQUEST[] variables safely behind any query. When submitted <form> fields match the database structure exactly it's even shorter:

pdo_query("INSERT INTO pages VALUES (?,?,?,?,?)", $_POST);

So much simplicity. But let's get back to some more rewriting advises and technical reasons on why you may want to get rid of mysql_ and escaping.

Fix or remove any oldschool sanitize() function

Once you have converted all mysql_ calls to pdo_query with bound params, remove all redundant pdo_real_escape_string calls.

In particular you should fix any sanitize or clean or filterThis or clean_data functions as advertised by dated tutorials in one form or the other:

function sanitize($str) {
   return trim(strip_tags(htmlentities(pdo_real_escape_string($str))));
}

Most glaring bug here is the lack of documentation. More significantly the order of filtering was in exactly the wrong order.

  • Correct order would have been: deprecatedly stripslashes as the innermost call, then trim, afterwards strip_tags, htmlentities for output context, and only lastly the _escape_string as its application should directly preceed the SQL intersparsing.

  • But as first step just get rid of the _real_escape_string call.

  • You may have to keep the rest of your sanitize() function for now if your database and application flow expect HTML-context-safe strings. Add a comment that it applies only HTML escaping henceforth.

  • String/value handling is delegated to PDO and its parameterized statements.

  • If there was any mention of stripslashes() in your sanitize function, it may indicate a higher level oversight.

    • That was commonly there to undo damage (double escaping) from the deprecated magic_quotes. Which however is best fixed centrally, not string by string.

    • Use one of the userland reversal approaches. Then remove the stripslashes() in the sanitize function.

    Historic note on magic_quotes. That feature is rightly deprecated. It's often incorrectly portrayed as failed security feature however. But magic_quotes are as much a failed security feature as tennis balls have failed as nutrition source. That simply wasn't their purpose.

    The original implementation in PHP2/FI introduced it explicitly with just "quotes will be automatically escaped making it easier to pass form data directly to msql queries". Notably it was accidentially safe to use with mSQL, as that supported ASCII only.
    Then PHP3/Zend reintroduced magic_quotes for MySQL and misdocumented it. But originally it was just a convenience feature, not intend for security.

How prepared statements differ

When you scramble string variables into the SQL queries, it doesn't just get more intricate for you to follow. It's also extraneous effort for MySQL to segregate code and data again.

SQL injections simply are when data bleeds into code context. A database server can't later spot where PHP originally glued variables inbetween query clauses.

With bound parameters you separate SQL code and SQL-context values in your PHP code. But it doesn't get shuffled up again behind the scenes (except with PDO::EMULATE_PREPARES). Your database receives the unvaried SQL commands and 1:1 variable values.

While this answer stresses that you should care about the readability advantages of dropping mysql_. There's occasionally also a performance advantage (repeated INSERTs with just differing values) due to this visible and technical data/code separation.

Beware that parameter binding still isn't a magic one-stop solution against all SQL injections. It handles the most common use for data/values. But can't whitelist column name / table identifiers, help with dynamic clause construction, or just plain array value lists.

Hybrid PDO use

These pdo_* wrapper functions make a coding-friendly stop-gap API. (It's pretty much what MYSQLI could have been if it wasn't for the idiosyncratic function signature shift). They also expose the real PDO at most times.
Rewriting doesn't have to stop at using the new pdo_ function names. You could one by one transition each pdo_query() into a plain $pdo->prepare()->execute() call.

It's best to start at simplifying again however. For example the common result fetching:

$result = pdo_query("SELECT * FROM tbl");
while ($row = pdo_fetch_assoc($result)) {

Can be replaced with just an foreach iteration:

foreach ($result as $row) {

Or better yet a direct and complete array retrieval:

$result->fetchAll();

You'll get more helpful warnings in most cases than PDO or mysql_ usually provide after failed queries.

Other options

So this hopefully visualized some practical reasons and a worthwile pathway to drop mysql_.

Just switching to doesn't quite cut it. pdo_query() is also just a frontend onto it.

Unless you also introduce parameter binding or can utilize something else from the nicer API, it's a pointless switch. I hope it's portrayed simple enough to not further the discouragement to newcomers. (Education usually works better than prohibition.)

While it qualifies for the simplest-thing-that-could-possibly-work category, it's also still very experimental code. I just wrote it over the weekend. There's a plethora of alternatives however. Just google for PHP database abstraction and browse a little. There always have been and will be lots of excellent libraries for such tasks.

If you want to simplify your database interaction further, mappers like Paris/Idiorm are worth a try. Just like nobody uses the bland DOM in JavaScript anymore, you don't have to babysit a raw database interface nowadays.

Printing 1 to 1000 without loop or conditionals

If POSIX solutions are accepted:

#include <stdio.h>
#include <signal.h>
#include <stdlib.h>
#include <sys/time.h>
#include <pthread.h>

static void die(int sig) {
    exit(0);
}

static void wakeup(int sig) {
    static int counter = 1;
    struct itimerval timer;
    float i = 1000 / (1000 - counter);

    printf("%d\n", counter++);

    timer.it_interval.tv_sec = 0;
    timer.it_interval.tv_usec = 0;
    timer.it_value.tv_sec = 0;
    timer.it_value.tv_usec = i; /* Avoid code elimination */
    setitimer(ITIMER_REAL, &timer, 0);
}

int main() {
    pthread_mutex_t mutex = PTHREAD_MUTEX_INITIALIZER;
    signal(SIGFPE, die);
    signal(SIGALRM, wakeup);
    wakeup(0);
    pthread_mutex_lock(&mutex);
    pthread_mutex_lock(&mutex); /* Deadlock, YAY! */
    return 0;
}

Android: How to create a Dialog without a title?

public static AlertDialog showAlertDialogWithoutTitle(Context context,String msg) 
     {
      AlertDialog.Builder alertDialogBuilder = new AlertDialog.Builder(context);
      alertDialogBuilder.setMessage(msg).setCancelable(false)
        .setPositiveButton("OK", new DialogInterface.OnClickListener() {
         public void onClick(DialogInterface dialog, int id) {

         }
        });

       return alertDialogBuilder.create(); 
     }

MVC ajax json post to controller action method

Below is how I got this working.

The Key point was: I needed to use the ViewModel associated with the view in order for the runtime to be able to resolve the object in the request.

[I know that that there is a way to bind an object other than the default ViewModel object but ended up simply populating the necessary properties for my needs as I could not get it to work]

[HttpPost]  
  public ActionResult GetDataForInvoiceNumber(MyViewModel myViewModel)  
  {            
     var invoiceNumberQueryResult = _viewModelBuilder.HydrateMyViewModelGivenInvoiceDetail(myViewModel.InvoiceNumber, myViewModel.SelectedCompanyCode);
     return Json(invoiceNumberQueryResult, JsonRequestBehavior.DenyGet);
  }

The JQuery script used to call this action method:

var requestData = {
         InvoiceNumber: $.trim(this.value),
         SelectedCompanyCode: $.trim($('#SelectedCompanyCode').val())
      };


      $.ajax({
         url: '/en/myController/GetDataForInvoiceNumber',
         type: 'POST',
         data: JSON.stringify(requestData),
         dataType: 'json',
         contentType: 'application/json; charset=utf-8',
         error: function (xhr) {
            alert('Error: ' + xhr.statusText);
         },
         success: function (result) {
            CheckIfInvoiceFound(result);
         },
         async: true,
         processData: false
      });

How to stop the Timer in android?

I had a similar problem and it was caused by the placement of the Timer initialisation.

It was placed in a method that was invoked oftener.

Try this:

Timer waitTimer;

  void exampleMethod() {

   if (waitTimer == null ) {
    //initialize your Timer here
    ...
   }

The "cancel()" method only canceled the latest Timer. The older ones were ignored an didn't stop running.

Html5 Placeholders with .NET MVC 3 Razor EditorFor extension?

I think create a custom EditorTemplate is not good solution, beause you need to care about many possible tepmlates for different cases: strings, numsers, comboboxes and so on. Other solution is custom extention to HtmlHelper.

Model:

public class MyViewModel
{
    [PlaceHolder("Enter title here")]
    public string Title { get; set; }
}

Html helper extension:

   public static MvcHtmlString BsEditorFor<TModel, TValue>(this HtmlHelper<TModel> htmlHelper,
    Expression<Func<TModel, TValue>> expression, string htmlClass = "")
{
    var modelMetadata = ModelMetadata.FromLambdaExpression(expression, htmlHelper.ViewData);
    var metadata = modelMetadata;

    var viewData = new
    {
        HtmlAttributes = new
            {
                @class = htmlClass,
                placeholder = metadata.Watermark,
            }
    };
    return htmlHelper.EditorFor(expression, viewData);

}

A corresponding view:

@Html.BsEditorFor(x => x.Title)

How to get content body from a httpclient call?

The way you are using await/async is poor at best, and it makes it hard to follow. You are mixing await with Task'1.Result, which is just confusing. However, it looks like you are looking at a final task result, rather than the contents.

I've rewritten your function and function call, which should fix your issue:

async Task<string> GetResponseString(string text)
{
    var httpClient = new HttpClient();

    var parameters = new Dictionary<string, string>();
    parameters["text"] = text;

    var response = await httpClient.PostAsync(BaseUri, new FormUrlEncodedContent(parameters));
    var contents = await response.Content.ReadAsStringAsync();

    return contents;
}

And your final function call:

Task<string> result = GetResponseString(text);
var finalResult = result.Result;

Or even better:

var finalResult = await GetResponseString(text);

What is the difference between visibility:hidden and display:none?

There is a big difference when it comes to child nodes. For example: If you have a parent div and a nested child div. So if you write like this:

<div id="parent" style="display:none;">
    <div id="child" style="display:block;"></div>
</div>

In this case none of the divs will be visible. But if you write like this:

<div id="parent" style="visibility:hidden;">
    <div id="child" style="visibility:visible;"></div>
</div>

Then the child div will be visible whereas the parent div will not be shown.

How to decompile an APK or DEX file on Android platform?

http://www.decompileandroid.com/

This website will decompile the code embedded in APK files and extract all the other assets in the file.

Java 8 lambdas, Function.identity() or t->t

In your example there is no big difference between str -> str and Function.identity() since internally it is simply t->t.

But sometimes we can't use Function.identity because we can't use a Function. Take a look here:

List<Integer> list = new ArrayList<>();
list.add(1);
list.add(2);

this will compile fine

int[] arrayOK = list.stream().mapToInt(i -> i).toArray();

but if you try to compile

int[] arrayProblem = list.stream().mapToInt(Function.identity()).toArray();

you will get compilation error since mapToInt expects ToIntFunction, which is not related to Function. Also ToIntFunction doesn't have identity() method.

PKIX path building failed in Java application

If you are using Eclipse just cross check in Eclipse Windows--> preferences---->java---> installed JREs is pointing the current JRE and the JRE where you have configured your certificate. If not remove the JRE and add the jre where your certificate is installed

Having services in React application

The first answer doesn't reflect the current Container vs Presenter paradigm.

If you need to do something, like validate a password, you'd likely have a function that does it. You'd be passing that function to your reusable view as a prop.

Containers

So, the correct way to do it is to write a ValidatorContainer, which will have that function as a property, and wrap the form in it, passing the right props in to the child. When it comes to your view, your validator container wraps your view and the view consumes the containers logic.

Validation could be all done in the container's properties, but it you're using a 3rd party validator, or any simple validation service, you can use the service as a property of the container component and use it in the container's methods. I've done this for restful components and it works very well.

Providers

If there's a bit more configuration necessary, you can use a Provider/Consumer model. A provider is a high level component that wraps somewhere close to and underneath the top application object (the one you mount) and supplies a part of itself, or a property configured in the top layer, to the context API. I then set my container elements to consume the context.

The parent/child context relations don't have to be near each other, just the child has to be descended in some way. Redux stores and the React Router function in this way. I've used it to provide a root restful context for my rest containers (if I don't provide my own).

(note: the context API is marked experimental in the docs, but I don't think it is any more, considering what's using it).

_x000D_
_x000D_
//An example of a Provider component, takes a preconfigured restful.js_x000D_
//object and makes it available anywhere in the application_x000D_
export default class RestfulProvider extends React.Component {_x000D_
 constructor(props){_x000D_
  super(props);_x000D_
_x000D_
  if(!("restful" in props)){_x000D_
   throw Error("Restful service must be provided");_x000D_
  }_x000D_
 }_x000D_
_x000D_
 getChildContext(){_x000D_
  return {_x000D_
   api: this.props.restful_x000D_
  };_x000D_
 }_x000D_
_x000D_
 render() {_x000D_
  return this.props.children;_x000D_
 }_x000D_
}_x000D_
_x000D_
RestfulProvider.childContextTypes = {_x000D_
 api: React.PropTypes.object_x000D_
};
_x000D_
_x000D_
_x000D_

Middleware

A further way I haven't tried, but seen used, is to use middleware in conjunction with Redux. You define your service object outside the application, or at least, higher than the redux store. During store creation, you inject the service into the middleware and the middleware handles any actions that affect the service.

In this way, I could inject my restful.js object into the middleware and replace my container methods with independent actions. I'd still need a container component to provide the actions to the form view layer, but connect() and mapDispatchToProps have me covered there.

The new v4 react-router-redux uses this method to impact the state of the history, for example.

_x000D_
_x000D_
//Example middleware from react-router-redux_x000D_
//History is our service here and actions change it._x000D_
_x000D_
import { CALL_HISTORY_METHOD } from './actions'_x000D_
_x000D_
/**_x000D_
 * This middleware captures CALL_HISTORY_METHOD actions to redirect to the_x000D_
 * provided history object. This will prevent these actions from reaching your_x000D_
 * reducer or any middleware that comes after this one._x000D_
 */_x000D_
export default function routerMiddleware(history) {_x000D_
  return () => next => action => {_x000D_
    if (action.type !== CALL_HISTORY_METHOD) {_x000D_
      return next(action)_x000D_
    }_x000D_
_x000D_
    const { payload: { method, args } } = action_x000D_
    history[method](...args)_x000D_
  }_x000D_
}
_x000D_
_x000D_
_x000D_

Is there a real solution to debug cordova apps

The best for me is to attach the Chrome debugger.

To do it, run your app in a emulator or device (using $cordova emulate)

then, open Google Chrome and go to chrome://inspect/

You'll see a list with running apps. Your app should be there. Click on "inspect".

A new window will open with developer tools. There you can click on "console" to check for errors

Pycharm does not show plot

I was facing above error when i am trying to plot histogram and below points worked for me.

OS : Mac Catalina 10.15.5

Pycharm Version : Community version 2019.2.3

Python version : 3.7

  1. I changed import statement as below (from - to)

from :

import matplotlib.pylab as plt

to:

import matplotlib.pyplot as plt

  1. and plot statement to below (changed my command form pyplot to plt)

from:

plt.pyplot.hist(df["horsepower"])

# set x/y labels and plot title
plt.pyplot.xlabel("horsepower")
plt.pyplot.ylabel("count")
plt.pyplot.title("horsepower bins") 

to :

plt.hist(df["horsepower"])

# set x/y labels and plot title
plt.xlabel("horsepower")
plt.ylabel("count")
plt.title("horsepower bins")
  1. use plt.show to display histogram

plt.show()

psql: FATAL: database "<user>" does not exist

By default, postgres tries to connect to a database with the same name as your user. To prevent this default behaviour, just specify user and database:

psql -U Username DatabaseName 

How to randomize Excel rows

Use Excel Online (Google Sheets).. And install Power Tools for Google Sheets.. Then in Google Sheets go to Addons tab and start Power Tools. Then choose Randomize from Power Tools menu. Select Shuffle. Then select choices of your test in excel sheet. Then select Cells in each row and click Shuffle from Power Tools menu. This will shuffle each row's selected cells independently from one another.

How do I add a foreign key to an existing SQLite table?

You can try this:

ALTER TABLE [Child] ADD COLUMN column_name INTEGER REFERENCES parent_table_name(column_id);

JSON to pandas DataFrame

Check this snip out.

# reading the JSON data using json.load()
file = 'data.json'
with open(file) as train_file:
    dict_train = json.load(train_file)

# converting json dataset from dictionary to dataframe
train = pd.DataFrame.from_dict(dict_train, orient='index')
train.reset_index(level=0, inplace=True)

Hope it helps :)

C# declare empty string array

If you are using .NET Framework 4.6 and later, they have some new syntax you can use:

using System;  // To pick up definition of the Array class.

var myArray = Array.Empty<string>();

Python foreach equivalent

This worked for me:

def smallest_missing_positive_integer(A):
A.sort()
N = len(A)

now = A[0]
for i in range(1, N, 1):
  next = A[i]
  
  #check if there is no gap between 2 numbers and if positive
  # "now + 1" is the "gap"
  if (next > now + 1):
    if now + 1 > 0:
      return now + 1 #return the gap
  now = next
    
return max(1, A[N-1] + 1) #if there is no positive number returns 1, otherwise the end of A+1

How to set time zone of a java.util.Date?

You could also set the timezone at the JVM level

Date date1 = new Date();
System.out.println(date1);

TimeZone.setDefault(TimeZone.getTimeZone("UTC"));
// or pass in a command line arg: -Duser.timezone="UTC"

Date date2 = new Date();
System.out.println(date2);

output:

Thu Sep 05 10:11:12 EDT 2013
Thu Sep 05 14:11:12 UTC 2013

UnicodeDecodeError: 'ascii' codec can't decode byte 0xc2

Python 2

The error is caused because ElementTree did not expect to find non-ASCII strings set the XML when trying to write it out. You should use Unicode strings for non-ASCII instead. Unicode strings can be made either by using the u prefix on strings, i.e. u'€' or by decoding a string with mystr.decode('utf-8') using the appropriate encoding.

The best practice is to decode all text data as it's read, rather than decoding mid-program. The io module provides an open() method which decodes text data to Unicode strings as it's read.

ElementTree will be much happier with Unicodes and will properly encode it correctly when using the ET.write() method.

Also, for best compatibility and readability, ensure that ET encodes to UTF-8 during write() and adds the relevant header.

Presuming your input file is UTF-8 encoded (0xC2 is common UTF-8 lead byte), putting everything together, and using the with statement, your code should look like:

with io.open('myText.txt', "r", encoding='utf-8') as f:
    data = f.read()

root = ET.Element("add")
doc = ET.SubElement(root, "doc")

field = ET.SubElement(doc, "field")
field.set("name", "text")
field.text = data

tree = ET.ElementTree(root)
tree.write("output.xml", encoding='utf-8', xml_declaration=True)

Output:

<?xml version='1.0' encoding='utf-8'?>
<add><doc><field name="text">data€</field></doc></add>

How can I autoplay a video using the new embed code style for Youtube?

You are using a wrong url for youtube auto play http://www.youtube.com/embed/JW5meKfy3fY&autoplay=1 this url display youtube id as wholeJW5meKfy3fY&autoplay=1 which youtube rejects to play. we have to pass autoplay variable to youtube, therefore you have to use ? instead of & so your url will be http://www.youtube.com/embed/JW5meKfy3fY?autoplay=1 and your final iframe will be like that.

<iframe src="http://www.youtube.com/embed/xzvScRnF6MU?autoplay=1" width="960" height="447" frameborder="0" allowfullscreen></iframe>

Handling data in a PHP JSON Object

You mean something like this?

<?php

$jsonurl = "http://search.twitter.com/trends.json";
$json = file_get_contents($jsonurl,0,null,null);
$json_output = json_decode($json);

foreach ( $json_output->trends as $trend )
{
    echo "{$trend->name}\n";
}

How can I redirect a php page to another php page?

While all of the other answers work, they all have one big problem: it is up to the browser to decide what to do if they encounter a Location header. Usually browser stop processing the request and redirect to the URI indicated with the Location header. But a malicious user could just ignore the Location header and continue its request. Furthermore there may be other things that cause the php interpreter to continue evaluating the script past the Location header, which is not what you intended.

Image this:

<?php
if (!logged_id()) {
    header("Location:login.php");
}

delete_everything();
?>

What you want and expected is that not logged in users are redirected to the login page, so that only logged in users can delete_everything. But if the script gets executed past the Location header still everything gets deleted. Thus, it is import to ALWAYS put an exit after a Location header, like this:

<?php
if (!logged_id()) {
    header("Location:login.php");
    exit; // <- don't forget this!
}

delete_everything();
?>

So, to answer your question: to redirect from a php page to another page (not just php, you can redirect to any page this way), use this:

<?php 

header("Location:http://www.example.com/some_page.php"); 
exit; // <- don't forget this!

?>

Small note: the HTTP standard says that you must provide absolute URLs in the Location header (http://... like in my example above) even if you just want to redirect to another file on the same domain. But in practice relative URLs (Location:some_page.php) work in all browsers, though not being standard compliant.