Programs & Examples On #Hilo

HiLo algorithm used for generating Ids for databases

Hibernate, @SequenceGenerator and allocationSize

I would check the DDL for the sequence in the schema. JPA Implementation is responsible only creation of the sequence with the correct allocation size. Therefore, if the allocation size is 50 then your sequence must have the increment of 50 in its DDL.

This case may typically occur with the creation of a sequence with allocation size 1 then later configured to allocation size 50 (or default) but the sequence DDL is not updated.

A Simple, 2d cross-platform graphics library for c or c++?

Heavy-weight:

  • GTK
  • QT
  • WxWidgets

Lightweight:

  • FLTK
  • Fox
  • Tk
  • Lua IUP
  • Ultimate++
  • dlib

Drawing frameworks without GUI widgets:

  • SDL
  • Cairo

How do I obtain a Query Execution Plan in SQL Server?

Explaining execution plan can be very detailed and takes up quite a reading time, but in summary if you use 'explain' before the query it should give you a lot of info including which parts were executed first and so. if you wanna read a bit more details about this, I compiled a small blog about this which points you as well to the right refs. https://medium.com/swlh/jetbrains-datagrip-explain-plan-ac406772c470

SQL DATEPART(dw,date) need monday = 1 and sunday = 7

Looks like the DATEFIRST settings is the only way, but it's not possible to make a SET statement in a scalar/table valued function. Therefore, it becomes very error-prone to the colleagues following your code. (become a trap to the others)

In fact, SQL server datepart function should be improved to accept this as parameter instead.

At the meantime, it looks like using the English Name of the week is the safest choice.

How to set a Fragment tag by code?

I know it's been 6 years ago but if anyone is facing the same problem do like I've done:

Create a custom Fragment Class with a tag field:

public class MyFragment extends Fragment {
 private String _myTag;
 public void setMyTag(String value)
 {
   if("".equals(value))
     return;
   _myTag = value;
 }
 //other code goes here
}

Before adding the fragment to the sectionPagerAdapter set the tag just like that:

 MyFragment mfrag= new MyFragment();
 mfrag.setMyTag("TAG_GOES_HERE");
 sectionPagerAdapter.AddFragment(mfrag);

What's wrong with foreign keys?

If you are absolutey sure, that the one underlying database system will not change in the future, I would use foreign keys to ensure data integrity.

But here is another very good real-life reason not to use foreign keys at all:

You are developing a product, which should support different database systems.

If you are working with the Entity Framework, which is able to connect to many different database systems, you may also want to support "open-source-free-of-charge" serverless databases. Not all of these databases may support your foreign key rules (updating, deleting rows...).

This can lead to different problems:

1.) You may run into errors, when the database structure is created or updated. Maybe there will only be silent errors, because your foreign keys are just ignored by the database system.

2.) If you rely on foreign keys, you will propably make less or even no data integrity checks in your business logic. Now, if the new database system does not support these foreign key rules or just behaves in a different way, you have to rewrite your business logic.

You may ask: Who needs different database systems? Well, not everybody can afford or wants a full blown SQL-Server on his machine. This is software, which needs to be maintained. Others already have invested time and money in some other DB system. Serverless database are great for small customers on only one machine.

Nobody knows, how all of these DB systems behave, but your business logic, with integrity checks, always stays the same.

When increasing the size of VARCHAR column on a large table could there be any problems?

In my case alter column was not working so one can use 'Modify' command, like:

alter table [table_name] MODIFY column [column_name] varchar(1200);

Allow docker container to connect to a local/host postgres database

Docker for Mac solution

17.06 onwards

Thanks to @Birchlabs' comment, now it is tons easier with this special Mac-only DNS name available:

docker run -e DB_PORT=5432 -e DB_HOST=docker.for.mac.host.internal

From 17.12.0-cd-mac46, docker.for.mac.host.internal should be used instead of docker.for.mac.localhost. See release note for details.

Older version

@helmbert's answer well explains the issue. But Docker for Mac does not expose the bridge network, so I had to do this trick to workaround the limitation:

$ sudo ifconfig lo0 alias 10.200.10.1/24

Open /usr/local/var/postgres/pg_hba.conf and add this line:

host    all             all             10.200.10.1/24            trust

Open /usr/local/var/postgres/postgresql.conf and edit change listen_addresses:

listen_addresses = '*'

Reload service and launch your container:

$ PGDATA=/usr/local/var/postgres pg_ctl reload
$ docker run -e DB_PORT=5432 -e DB_HOST=10.200.10.1 my_app 

What this workaround does is basically same with @helmbert's answer, but uses an IP address that is attached to lo0 instead of docker0 network interface.

What is a serialVersionUID and why should I use it?

It would be nice if CheckStyle could verify that the serialVersionUID on a class that implements Serializable has a good value, i.e. that it matches what the serial version id generator would produce. If you have a project with lots of serializable DTOs, for example, remembering to delete the existing serialVersionUID and regenerate it is a pain, and currently the only way (that I know of) to verify this is to regenerate for each class and compare to the old one. This is very very painful.

Angular js init ng-model from default values

As others pointed out, it is not good practice to initialize data on views. Initializing data on Controllers, however, is recommended. (see http://docs.angularjs.org/guide/controller)

So you can write

<input name="card[description]" ng-model="card.description">

and

$scope.card = { description: 'Visa-4242' };

$http.get('/getCardInfo.php', function(data) {
   $scope.card = data;
});

This way the views do not contain data, and the controller initializes the value while the real values are being loaded.

Python update a key in dict if it doesn't exist

Use dict.setdefault():

>>> d = {1: 'one'}
>>> d.setdefault(1, '1')
'one'
>>> d    # d has not changed because the key already existed
{1: 'one'}
>>> d.setdefault(2, 'two')
'two'
>>> d
{1: 'one', 2: 'two'}

PHP function to generate v4 UUID

I'm sure there's a more elegant way to do the conversion from binary to decimal for the 4xxx and yxxx portions. But if you want to use openssl_random_pseudo_bytes as your crytographically secure number generator, this is what I use:

return sprintf('%s-%s-%04x-%04x-%s',
    bin2hex(openssl_random_pseudo_bytes(4)),
    bin2hex(openssl_random_pseudo_bytes(2)),
    hexdec(bin2hex(openssl_random_pseudo_bytes(2))) & 0x0fff | 0x4000,
    hexdec(bin2hex(openssl_random_pseudo_bytes(2))) & 0x3fff | 0x8000,
    bin2hex(openssl_random_pseudo_bytes(6))
    );

error: expected class-name before ‘{’ token

I got the same error with a different problem,

I used namespaces in my headers and forgot the closing bracket and got this cryptic error instead.

Set textarea width to 100% in bootstrap modal

I had the same problem. I fixed it by adding this piece of code inside the text area's style.

resize: vertical;

You can check the Bootstrap reference here

Time stamp in the C programming language

Also making aware of interactions between clock() and usleep(). usleep() suspends the program, and clock() only measures the time the program is running.

If might be better off to use gettimeofday() as mentioned here

Finding the Eclipse Version Number

I think, the easiest way is to read readme file inside your Eclipse directory at path eclipse/readme/eclipse_readme .

At the very top of this file it clearly tells the version number:

For My Eclipse Juno; it says version as Release 4.2.0

Random number generator only generating one random number

There are a lot of solutions, here one: if you want only number erase the letters and the method receives a random and the result length.

public String GenerateRandom(Random oRandom, int iLongitudPin)
{
    String sCharacters = "123456789ABCDEFGHIJKLMNPQRSTUVWXYZ123456789";
    int iLength = sCharacters.Length;
    char cCharacter;
    int iLongitudNuevaCadena = iLongitudPin; 
    String sRandomResult = "";
    for (int i = 0; i < iLongitudNuevaCadena; i++)
    {
        cCharacter = sCharacters[oRandom.Next(iLength)];
        sRandomResult += cCharacter.ToString();
    }
    return (sRandomResult);
}

Creating multiline strings in JavaScript

The equivalent in javascript is:

var text = `
This
Is
A
Multiline
String
`;

Here's the specification. See browser support at the bottom of this page. Here are some examples too.

What is a regular expression for a MAC Address?

delimiter: ":","-","."

double or single: 00 = 0, 0f = f

/^([0-9a-f]{1,2}[\.:-]){5}([0-9a-f]{1,2})$/i

or

/^([0-9a-F]{1,2}[\.:-]){5}([0-9a-F]{1,2})$/


exm: 00:27:0e:2a:b9:aa, 00-27-0E-2A-B9-AA, 0.27.e.2a.b9.aa ...

Laravel: getting a a single value from a MySQL query

As of Laravel >= 5.3, best way is to use value:

$groupName = \App\User::where('username',$username)->value('groupName');

or

use App\User;//at top of controller
$groupName = User::where('username',$username)->value('groupName');//inside controller function

Of course you have to create a model User for users table which is most efficient way to interact with database tables in Laravel.

Import one schema into another new schema - Oracle

The issue was with the dmp file itself. I had to re-export the file and the command works fine. Thank you @Justin Cave

How to get the current time in milliseconds from C in Linux?

This version need not math library and checked the return value of clock_gettime().

#include <time.h>
#include <stdlib.h>
#include <stdint.h>

/**
 * @return milliseconds
 */
uint64_t get_now_time() {
  struct timespec spec;
  if (clock_gettime(1, &spec) == -1) { /* 1 is CLOCK_MONOTONIC */
    abort();
  }

  return spec.tv_sec * 1000 + spec.tv_nsec / 1e6;
}

How to auto-indent code in the Atom editor?

You can just quickly open up the command palette and do it there
Cmd + Shift + p and search for Editor: Auto Indent:

screenshot

How to get script of SQL Server data?

From the SQL Server Management Studio you can right click on your database and select:

Tasks -> Generate Scripts

Then simply proceed through the wizard. Make sure to set 'Script Data' to TRUE when prompted to choose the script options.

SQL Server 2008 R2

alt text

Further reading:

How does one make random number between range for arc4random_uniform()?

The answer is just 1 line code:

let randomNumber = arc4random_uniform(8999) + 1000 //for 4 digit random number
let randomNumber = arc4random_uniform(899999999) + 100000000 //for 9 digit random number
let randomNumber = arc4random_uniform(89) + 10    //for 2 digit random number
let randomNumber = arc4random_uniform(899) + 100  //for 3 digit random number

The alternate solution is:

    func generateRandomNumber(numDigits: Int) -> Int{
    var place = 1
    var finalNumber = 0;
    var finanum = 0;
    for var i in 0 ..< numDigits {
        place *= 10
        let randomNumber = arc4random_uniform(10)         
        finalNumber += Int(randomNumber) * place
        finanum = finalNumber / 10
           i += 1
    }
    return finanum
}

Although the drawback is that number cannot start from 0.

React Native version mismatch

Try installing the dependencies again. That worked for me-

1.) yarn/npm install
2.) yarn/npm start --reset-cache

Jquery select change not firing

Try

 $(document).on('change','#multiid',function(){
    alert('Change Happened');
});

As your select-box is generated from the code, so you have to use event delegation, where in place of $(document) you can have closest parent element.

Or

$(document.body).on('change','#multiid',function(){
    alert('Change Happened');
});

Update:

Second one works fine, there is another change of selector to make it work.

$('#addbasket').on('change','#multiid',function(){
    alert('Change Happened');
});

Ideally we should use $("#addbasket") as it's the closest parent element [As i have mentioned above].

Find the number of employees in each department - SQL Oracle

Try to do this:

SQL> select dept,count(*) "no of emp" from employee group by dept;

DEPT                  no of emp
-------------------- ----------
HR                            2
Account                       2
Admin                         3

What is the --save option for npm install?

Update as of npm 5:

As of npm 5.0.0, installed modules are added as a dependency by default, so the --save option is no longer needed. The other save options still exist and are listed in the documentation for npm install.


Original Answer:

To add package in dependencies:

npm install my_dep --save

or

npm install my_dep -S

or

npm i my_dep -S

To add package in devDependencies

npm install my_test_framework --save-dev

or

npm install my_test_framework -D

or

npm i my_test_framework -D

package.json enter image description here

Check if table exists

Adding to Gaby's post, my jdbc getTables() for Oracle 10g requires all caps to work:

"employee" -> "EMPLOYEE"

Otherwise I would get an exception:

java.sql.SqlExcepcion exhausted resultset

(even though "employee" is in the schema)

Set SSH connection timeout

The ConnectTimeout option allows you to tell your ssh client how long you're willing to wait for a connection before returning an error. By setting ConnectTimeout to 1, you're effectively saying "try for at most 1 second and then fail if you haven't connected yet".

The problem is that when you connect by name, the DNS lookup can take several seconds. Connecting by IP address is much faster, and may actually work in one second or less. What sinelaw is experiencing is that every attempt to connect by DNS name is failing to occur within one second. The default setting of ConnectTimeout defers to the linux kernel connect timeout, which is usually pretty long.

Failed to allocate memory: 8

You only need to edit your virtual device's ram, making it lower! Try 20 MB, and it will work!

JPA 2.0, Criteria API, Subqueries, In Expressions

You can use double join, if table A B are connected only by table AB.

public static Specification<A> findB(String input) {
    return (Specification<A>) (root, cq, cb) -> {
        Join<A,AB> AjoinAB = root.joinList(A_.AB_LIST,JoinType.LEFT);
        Join<AB,B> ABjoinB = AjoinAB.join(AB_.B,JoinType.LEFT);
        return cb.equal(ABjoinB.get(B_.NAME),input);
    };
}

That's just an another option
Sorry for that timing but I have came across this question and I also wanted to make SELECT IN but I didn't even thought about double join. I hope it will help someone.

Split string into individual words Java

Yet another method, using StringTokenizer :

String s = "I want to walk my dog";
StringTokenizer tokenizer = new StringTokenizer(s);

while(tokenizer.hasMoreTokens()) {
    System.out.println(tokenizer.nextToken());
}

How to set selected index JComboBox by value

public static void setSelectedValue(JComboBox comboBox, int value)
    {
        ComboItem item;
        for (int i = 0; i < comboBox.getItemCount(); i++)
        {
            item = (ComboItem)comboBox.getItemAt(i);
            if (item.getValue().equalsIgnoreCase(value))
            {
                comboBox.setSelectedIndex(i);
                break;
            }
        }
    }

Hope this help :)

Xcode 10.2.1 Command PhaseScriptExecution failed with a nonzero exit code

In my case was that I changed a line in a script of my Xcode project and that line was badly written (I forgot to add ";" at the end of the line). So I added the ";" and clean and build project.

Laravel Check If Related Model Exists

I prefer to use exists method:

RepairItem::find($id)->option()->exists()

to check if related model exists or not. It's working fine on Laravel 5.2

How to loop through all the files in a directory in c # .net?

string[] files = 
    Directory.GetFiles(txtPath.Text, "*ProfileHandler.cs", SearchOption.AllDirectories);

That last parameter effects exactly what you're referring to. Set it to AllDirectories for every file including in subfolders, and set it to TopDirectoryOnly if you only want to search in the directory given and not subfolders.

Refer to MDSN for details: https://msdn.microsoft.com/en-us/library/ms143316(v=vs.110).aspx

What is the Eclipse shortcut for "public static void main(String args[])"?

To get public static void main(String[] args) line in eclipse without typing the whole line type "main" and press Ctrl + space then, you will get the option for the main method select it.

enter image description here

extract date only from given timestamp in oracle sql

This is exactly what TO_DATE() is for: to convert timestamp to date.

Just use TO_DATE(sysdate) instead of TO_CHAR(sysdate, 'YYYY/MM/DD-HH24-MI-SS-SSSSS').

SQLFiddle demo

UPDATE:

Per your update, your cdate column is not real DATE or TIMESTAMP type, but VARCHAR2. It is not very good idea to use string types to keep dates. It is very inconvenient and slow to search, compare and do all other kinds of math on dates.

You should convert your cdate VARCHAR2 field into real TIMESTAMP. Assuming there are no other users for this field except for your code, you can convert cdate to timestamp as follows:

BEGIN TRANSACTION;
-- add new temp field tdate:
ALTER TABLE mytable ADD tdate TIMESTAMP;
-- save cdate to tdate while converting it:
UPDATE mytable SET tdate = to_date(cdate, 'YYYY-MM-DD HH24:MI:SS');

-- you may want to check contents of tdate before next step!!!

-- drop old field
ALTER TABLE mytable DROP COLUMN cdate;
-- rename tdate to cdate:
ALTER TABLE mytable RENAME COLUMN tdate TO cdate;
COMMIT;

SQLFiddle Demo

PDO closing connection

According to documentation you're correct (http://php.net/manual/en/pdo.connections.php):

The connection remains active for the lifetime of that PDO object. To close the connection, you need to destroy the object by ensuring that all remaining references to it are deleted--you do this by assigning NULL to the variable that holds the object. If you don't do this explicitly, PHP will automatically close the connection when your script ends.

Note that if you initialise the PDO object as a persistent connection it will not automatically close the connection.

How can I give an imageview click effect like a button on Android?

Set the selectable background to the ImageView and add some padding. Then attach the OnClickListener.

<ImageView
    android:id="@+id/your_image_view"
    android:layout_width="wrap_content"
    android:layout_height="wrap_content"
    android:src="@drawable/your_image"
    android:padding="10dp"
    android:background="?android:attr/selectableItemBackground"/>

How to pass arguments and redirect stdin from a file to program run in gdb?

You can do this:

gdb --args path/to/executable -every -arg you can=think < of

The magic bit being --args.

Just type run in the gdb command console to start debugging.

how to convert object to string in java

Looking at the output, it seems that your "temp" is a String array. You need to loop across the array to display each value.

Finding rows that don't contain numeric data in Oracle

After doing some testing, i came up with this solution, let me know in case it helps.

Add this below 2 conditions in your query and it will find the records which don't contain numeric data

 and REGEXP_LIKE(<column_name>, '\D') -- this selects non numeric data
 and not REGEXP_LIKE(column_name,'^[-]{1}\d{1}') -- this filters out negative(-) values

how to check confirm password field in form without reloading page

Try this one ;

CSS

#indicator{
    width:20px;
    height:20px;
    display:block;
    border-radius:10px;
}
.green{
    background-color:green; 
    display:block;
}
.red{
    background-color:red;   
    display:block;
}

HTML

<form id="form" name="form" method="post" action="registration.php"> 
    <label >username : 
    <input name="username" id="username" type="text" /></label> <br>
    <label >password : 
    <input name="password" id="password" type="password" id="password" /></label>      <br>
    <label>confirm password:
    <input type="password" name="confirm_password" id="confirm_password" /><span id="indicator"></span> <br>
    </label>
    <label>
    <input type="submit" name="submit" id="regbtn"  value="registration"  />
    </label>
</form>

JQuery

$('#confirm_password').keyup(function(){
    var pass    =   $('#password').val();
    var cpass   =   $('#confirm_password').val();
    if(pass!=cpass){
        $('#indicator').attr({class:'red'});
        $('#regbtn').attr({disabled:true});
    }
    else{
        $('#indicator').attr({class:'green'});
        $('#regbtn').attr({disabled:false});
    }
});

GROUP BY and COUNT in PostgreSQL

There is also EXISTS:

SELECT count(*) AS post_ct
FROM   posts p
WHERE  EXISTS (SELECT FROM votes v WHERE v.post_id = p.id);

In Postgres and with multiple entries on the n-side like you probably have, it's generally faster than count(DISTINCT post_id):

SELECT count(DISTINCT p.id) AS post_ct
FROM   posts p
JOIN   votes v ON v.post_id = p.id;

The more rows per post there are in votes, the bigger the difference in performance. Test with EXPLAIN ANALYZE.

count(DISTINCT post_id) has to read all rows, sort or hash them, and then only consider the first per identical set. EXISTS will only scan votes (or, preferably, an index on post_id) until the first match is found.

If every post_id in votes is guaranteed to be present in the table posts (referential integrity enforced with a foreign key constraint), this short form is equivalent to the longer form:

SELECT count(DISTINCT post_id) AS post_ct
FROM   votes;

May actually be faster than the EXISTS query with no or few entries per post.

The query you had works in simpler form, too:

SELECT count(*) AS post_ct
FROM  (
    SELECT FROM posts 
    JOIN   votes ON votes.post_id = posts.id 
    GROUP  BY posts.id
    ) sub;

Benchmark

To verify my claims I ran a benchmark on my test server with limited resources. All in a separate schema:

Test setup

Fake a typical post / vote situation:

CREATE SCHEMA y;
SET search_path = y;

CREATE TABLE posts (
  id   int PRIMARY KEY
, post text
);

INSERT INTO posts
SELECT g, repeat(chr(g%100 + 32), (random()* 500)::int)  -- random text
FROM   generate_series(1,10000) g;

DELETE FROM posts WHERE random() > 0.9;  -- create ~ 10 % dead tuples

CREATE TABLE votes (
  vote_id serial PRIMARY KEY
, post_id int REFERENCES posts(id)
, up_down bool
);

INSERT INTO votes (post_id, up_down)
SELECT g.* 
FROM  (
   SELECT ((random()* 21)^3)::int + 1111 AS post_id  -- uneven distribution
        , random()::int::bool AS up_down
   FROM   generate_series(1,70000)
   ) g
JOIN   posts p ON p.id = g.post_id;

All of the following queries returned the same result (8093 of 9107 posts had votes).
I ran 4 tests with EXPLAIN ANALYZE ant took the best of five on Postgres 9.1.4 with each of the three queries and appended the resulting total runtimes.

  1. As is.

  2. After ..

    ANALYZE posts;
    ANALYZE votes;
    
  3. After ..

    CREATE INDEX foo on votes(post_id);
    
  4. After ..

    VACUUM FULL ANALYZE posts;
    CLUSTER votes using foo;
    

count(*) ... WHERE EXISTS

  1. 253 ms
  2. 220 ms
  3. 85 ms -- winner (seq scan on posts, index scan on votes, nested loop)
  4. 85 ms

count(DISTINCT x) - long form with join

  1. 354 ms
  2. 358 ms
  3. 373 ms -- (index scan on posts, index scan on votes, merge join)
  4. 330 ms

count(DISTINCT x) - short form without join

  1. 164 ms
  2. 164 ms
  3. 164 ms -- (always seq scan)
  4. 142 ms

Best time for original query in question:

  • 353 ms

For simplified version:

  • 348 ms

@wildplasser's query with a CTE uses the same plan as the long form (index scan on posts, index scan on votes, merge join) plus a little overhead for the CTE. Best time:

  • 366 ms

Index-only scans in the upcoming PostgreSQL 9.2 can improve the result for each of these queries, most of all for EXISTS.

Related, more detailed benchmark for Postgres 9.5 (actually retrieving distinct rows, not just counting):

What is the best method of handling currency/money?

Simple code for Ruby & Rails

<%= number_to_currency(1234567890.50) %>

OUT PUT => $1,234,567,890.50

How do I clear all variables in the middle of a Python script?

No, you are best off restarting the interpreter

IPython is an excellent replacement for the bundled interpreter and has the %reset command which usually works

How can I tell AngularJS to "refresh"

Use

$route.reload();

remember to inject $route to your controller.

react-router getting this.props.location in child components

If the above solution didn't work for you, you can use import { withRouter } from 'react-router-dom';


Using this you can export your child class as -

class MyApp extends Component{
    // your code
}

export default withRouter(MyApp);

And your class with Router -

// your code
<Router>
      ...
      <Route path="/myapp" component={MyApp} />
      // or if you are sending additional fields
      <Route path="/myapp" component={() =><MyApp process={...} />} />
<Router>

Sort array of objects by object fields

Use usort, here's an example adapted from the manual:

function cmp($a, $b) {
    return strcmp($a->name, $b->name);
}

usort($your_data, "cmp");

You can also use any callable as the second argument. Here are some examples:

  • Using anonymous functions (from PHP 5.3)

      usort($your_data, function($a, $b) {return strcmp($a->name, $b->name);});
    
  • From inside a class

      usort($your_data, array($this, "cmp")); // "cmp" should be a method in the class
    
  • Using arrow functions (from PHP 7.4)

      usort($your_data, fn($a, $b) => strcmp($a->name, $b->name));
    

Also, if you're comparing numeric values, fn($a, $b) => $a->count - $b->count as the "compare" function should do the trick, or, if you want yet another way of doing the same thing, starting from PHP 7 you can use the Spaceship operator, like this: fn($a, $b) => $a->count <=> $b->count.

How to show full object in Chrome console?

var gandalf = {
  "real name": "Gandalf",
  "age (est)": 11000,
  "race": "Maia",
  "haveRetirementPlan": true,
  "aliases": [
    "Greyhame",
    "Stormcrow",
    "Mithrandir",
    "Gandalf the Grey",
    "Gandalf the White"
  ]
};
//to console log object, we cannot use console.log("Object gandalf: " + gandalf);
console.log("Object gandalf: ");
//this will show object gandalf ONLY in Google Chrome NOT in IE
console.log(gandalf);
//this will show object gandalf IN ALL BROWSERS!
console.log(JSON.stringify(gandalf));
//this will show object gandalf IN ALL BROWSERS! with beautiful indent
console.log(JSON.stringify(gandalf, null, 4));

Bootstrap 3.0 Popovers and tooltips

I use this on all my pages to enable tooltip

$(function () { $("[data-toggle='tooltip']").tooltip(); });

Remove last character from C++ string

str.erase( str.end()-1 )

Reference: std::string::erase() prototype 2

no c++11 or c++0x needed.

Change URL without refresh the page

When you use a function ...

<p onclick="update_url('/en/step2');">Link</p>

<script>
function update_url(url) {
    history.pushState(null, null, url);
}
</script>

return query based on date

If you want to get all new things in the past 5 minutes you would have to do some calculations, but its not hard...

First create an index on the property you want to match on (include sort direction -1 for descending and 1 for ascending)

db.things.createIndex({ createdAt: -1 }) // descending order on .createdAt

Then query for documents created in the last 5 minutes (60 seconds * 5 minutes)....because javascript's .getTime() returns milliseconds you need to mulitply by 1000 before you use it as input to the new Date() constructor.

db.things.find({
        createdAt: {
            $gte: new Date(new Date().getTime()-60*5*1000).toISOString()
         }
     })
     .count()

Explanation for new Date(new Date().getTime()-60*5*1000).toISOString() is as follows:

First we calculate "5 minutes ago":

  1. new Date().getTime() gives us current time in milliseconds
  2. We want to subtract 5 minutes (in ms) from that: 5*60*1000 -- I just multiply by 60 seconds so its easy to change. I can just change 5 to 120 if I want 2 hours (120 minutes).
  3. new Date().getTime()-60*5*1000 gives us 1484383878676 (5 minutes ago in ms)

Now we need to feed that into a new Date() constructor to get the ISO string format required by MongoDB timestamps.

  1. { $gte: new Date(resultFromAbove).toISOString() } (mongodb .find() query)
  2. Since we can't have variables we do it all in one shot: new Date(new Date().getTime()-60*5*1000)
  3. ...then convert to ISO string: .toISOString()
  4. new Date(new Date().getTime()-60*5*1000).toISOString() gives us 2017-01-14T08:53:17.586Z

Of course this is a little easier with variables if you're using the node-mongodb-native driver, but this works in the mongo shell which is what I usually use to check things.

SQL Query to search schema of all tables

  select object_name(c.object_id) as table_name
    , schema_name(t.schema_id) as schema_name
    from sys.columns c
    join sys.tables t on c.object_id = t.object_id
     where c.name=N'CreatedDate';

It gets a little more complicated if you want alsoother table properties, but you'll refer to the object catalog views like sys.tables, sys.columns etc.

Matrix Multiplication in pure Python?

If you really don't want to use numpy you can do something like this:

def matmult(a,b):
    zip_b = zip(*b)
    # uncomment next line if python 3 : 
    # zip_b = list(zip_b)
    return [[sum(ele_a*ele_b for ele_a, ele_b in zip(row_a, col_b)) 
             for col_b in zip_b] for row_a in a]

x = [[1,2,3],[4,5,6],[7,8,9],[10,11,12]]
y = [[1,2],[1,2],[3,4]]

import numpy as np # I want to check my solution with numpy

mx = np.matrix(x)
my = np.matrix(y)       

Result:

>>> matmult(x,y)
[[12, 18], [27, 42], [42, 66], [57, 90]]
>>> mx * my
matrix([[12, 18],
        [27, 42],
        [42, 66],
        [57, 90]])

ORACLE convert number to string

Using the FM format model modifier to get close, as you won't get the trailing zeros after the decimal separator; but you will still get the separator itself, e.g. 50.. You can use rtrim to get rid of that:

select to_char(a, '99D90'),
    to_char(a, '90D90'),
    to_char(a, 'FM90D99'),
    rtrim(to_char(a, 'FM90D99'), to_char(0, 'D'))
from (
    select 50 a from dual
    union all select 50.57 from dual
    union all select 5.57 from dual
    union all select 0.35 from dual
    union all select 0.4 from dual
)
order by a;

TO_CHA TO_CHA TO_CHA RTRIM(
------ ------ ------ ------
   .35   0.35 0.35   0.35
   .40   0.40 0.4    0.4
  5.57   5.57 5.57   5.57
 50.00  50.00 50.    50
 50.57  50.57 50.57  50.57

Note that I'm using to_char(0, 'D') to generate the character to trim, to match the decimal separator - so it looks for the same character, , or ., as the first to_char adds.

The slight downside is that you lose the alignment. If this is being used elsewhere it might not matter, but it does then you can also wrap it in an lpad, which starts to make it look a bit complicated:

...
lpad(rtrim(to_char(a, 'FM90D99'), to_char(0, 'D')), 6)
...

TO_CHA TO_CHA TO_CHA RTRIM( LPAD(RTRIM(TO_CHAR(A,'FM
------ ------ ------ ------ ------------------------
   .35   0.35 0.35   0.35     0.35
   .40   0.40 0.4    0.4       0.4
  5.57   5.57 5.57   5.57     5.57
 50.00  50.00 50.    50         50
 50.57  50.57 50.57  50.57   50.57

Python - 'ascii' codec can't decode byte

In case you're dealing with Unicode, sometimes instead of encode('utf-8'), you can also try to ignore the special characters, e.g.

"??".encode('ascii','ignore')

or as something.decode('unicode_escape').encode('ascii','ignore') as suggested here.

Not particularly useful in this example, but can work better in other scenarios when it's not possible to convert some special characters.

Alternatively you can consider replacing particular character using replace().

Find a value anywhere in a database

If you need to run such search only once then you can probably go with any of the scripts already shown in other answers. But otherwise, I’d recommend using ApexSQL Search for this. It’s a free SSMS addin and it really saved me a lot of time.

Before running any of the scripts you should customize it based on the data type you want to search. If you know you are searching for datetime column then there is no need to search through nvarchar columns. This will speed up all of the queries above.

How to check null objects in jQuery

In jQuery 1.4 you get the $.isEmptyObject function, but if you are forced to use an older version of jQ like us poor Drupal developers just steal use this code:

// This is a function similar to the jQuery 1.4 $.isEmptyObject.
function isObjectEmpty(obj) {
  for ( var name in obj ) {
    return false;
  }
  return true;
}

Use it like:

console.log(isObjectEmpty(the_object)); // Returns true or false.

Validate Dynamically Added Input fields

You should have 'name' attribute for your inputs. You need to add the rules dynamically, one option is to add them when the form submits.

And here is my solution that I've tested and it works:

<script type="text/javascript">
   $(document).ready(function() {
        var numberIncr = 1; // used to increment the name for the inputs

        function addInput() {
            $('#inputs').append($('<input class="comment" name="name'+numberIncr+'" />'));
            numberIncr++;
        }

        $('form.commentForm').on('submit', function(event) {

            // adding rules for inputs with class 'comment'
            $('input.comment').each(function() {
                $(this).rules("add", 
                    {
                        required: true
                    })
            });            

            // prevent default submit action         
            event.preventDefault();

            // test if form is valid 
            if($('form.commentForm').validate().form()) {
                console.log("validates");
            } else {
                console.log("does not validate");
            }
        })

        // set handler for addInput button click
        $("#addInput").on('click', addInput);

        // initialize the validator
        $('form.commentForm').validate();

   });


</script>

And the html form part:

<form class="commentForm" method="get" action="">
    <div>

        <p id="inputs">    
            <input class="comment" name="name0" />
        </p>

    <input class="submit" type="submit" value="Submit" />
    <input type="button" value="add" id="addInput" />

    </div>
</form>

Good luck! Please approve answer if it suits you!

Found conflicts between different versions of the same dependent assembly that could not be resolved

I followed the advice of several of the responses here to figure out what was wrong, but none of the answers seemed to explain how to fix it. My issue was that one reference required a different version of a second reference. So Newtonsoft was at version 6, but some other DLL wanted 4.5. Then I upgraded Newtonsoft as one of the other answers suggested and that made things worse.

So I actually downgraded my Newtonsoft install and the warning went away (VS 2017):

Right click References in the solution explorer and select Manage NuGet Packages... Under the "Installed" tab, find Newtonsoft (or whatever your conflict is) On the right side, a dropdown appears next to "Version" that you can change to older versions. It wasn't obvious to me that this dropdown could be used to downgrade.

Print: Entry, ":CFBundleIdentifier", Does Not Exist

Try to look into previous error message happened before current error i.e., "CFBundleIdentifier”, Does Not Exist.

Fix previous error then this error should disappear.

I fixed previous duplicate symbols for architecture error when run react-native run-ios --simulator="iPad Pro (9.7-inch), then the problem gone.

Cannot find module '../build/Release/bson'] code: 'MODULE_NOT_FOUND' } js-bson: Failed to load c++ bson extension, using pure JS version

First I just find in npm module mongodb the file index.js ..node_modules\mongodb\node_modules\bson\ext\index.js

and change path to js version in catch block

bson = require('../build/Release/bson'); to bson = require('../browser_build/bson');

but then I just changed it like this, all the similar... previously installed the module... : bson = require('bson');

How to add a button to UINavigationBar?

swift 3

    let cancelBarButton = UIBarButtonItem(title: "Cancel", style: .done, target: self, action: #selector(cancelPressed(_:)))
    cancelBarButton.setTitleTextAttributes( [NSFontAttributeName : UIFont.cancelBarButtonFont(),
                                                          NSForegroundColorAttributeName : UIColor.white], for: .normal)
    self.navigationItem.leftBarButtonItem = cancelBarButton


    func cancelPressed(_ sender: UIBarButtonItem ) {
        self.dismiss(animated: true, completion: nil)
    }

CSS: background-color only inside the margin

That is not possible du to the Box Model. However you could use a workaround with css3's border-image, or border-color in general css.

However im unsure whether you may have a problem with resetting. Some browsers do set a margin to html as well. See Eric Meyers Reset CSS for more!

html{margin:0;padding:0;}

Spring cannot find bean xml configuration file when it does exist

I have stuck in this issue for a while and I have came to the following solution

  1. Create an ApplicationContextAware class (which is a class that implements the ApplicationContextAware)
  2. In ApplicationContextAware we have to implement the one method only

    public void setApplicationContext(ApplicationContext context) throws BeansException

  3. Tell the spring context about this new bean (I call it SpringContext)

    bean id="springContext" class="packe.of.SpringContext" />
    

Here is the code snippet

import org.springframework.beans.BeansException;
import org.springframework.context.ApplicationContext;
import org.springframework.context.ApplicationContextAware;

public class SpringContext implements ApplicationContextAware {
  private static ApplicationContext context;

  @Override
  public void setApplicationContext(ApplicationContext context) throws BeansException {
    this.context = context;
  }
  public static ApplicationContext getApplicationContext() {
    return context;
  }
}
  1. Then you can call any method of application context outside the spring context for example

    
    SomeServiceClassOrComponent utilityService SpringContext.getApplicationContext().getBean(SomeServiceClassOrComponent .class);
    

I hope this will solve the problem for many users

How can I use UIColorFromRGB in Swift?

I wanted to put

cell.backgroundColor = UIColor.colorWithRed(125/255.0, green: 125/255.0, blue: 125/255.0, alpha: 1.0)  

but that didn't work.

So I used:
For Swift

cell.backgroundColor = UIColor(red: 0.5, green: 0.5, blue: 0.5, alpha: 1.0)  

So this is the workaround that I found.

ComboBox SelectedItem vs SelectedValue

If you want Selected.Value being worked you have to do following things:

1. Set DisplayMember
2. Set ValueMember
3. Set DataSource (not use Items.Add, Items.AddRange, DataBinding etc.)

The key point is Set DataSource!

How to set the holo dark theme in a Android app?

According the android.com, you only need to set it in the AndroidManifest.xml file:

http://developer.android.com/guide/topics/ui/themes.html#ApplyATheme

Adding the theme attribute to your application element worked for me:

--AndroidManifest.xml--

...

<application ...

  android:theme="@android:style/Theme.Holo"/>
  ...

</application>

how to save and read array of array in NSUserdefaults in swift?

Here is an example of reading and writing a list of objects of type SNStock that implements NSCoding - we have an accessor for the entire list, watchlist, and two methods to add and remove objects, that is addStock(stock: SNStock) and removeStock(stock: SNStock).

import Foundation

class DWWatchlistController {

  private let kNSUserDefaultsWatchlistKey: String = "dw_watchlist_key"

  private let userDefaults: NSUserDefaults

  private(set) var watchlist:[SNStock] {

    get {
      if let watchlistData : AnyObject = userDefaults.objectForKey(kNSUserDefaultsWatchlistKey) {
        if let watchlist : AnyObject = NSKeyedUnarchiver.unarchiveObjectWithData(watchlistData as! NSData) {
          return watchlist as! [SNStock]
        }
      }
      return []
    }

    set(watchlist) {
      let watchlistData = NSKeyedArchiver.archivedDataWithRootObject(watchlist)
      userDefaults.setObject(watchlistData, forKey: kNSUserDefaultsWatchlistKey)
      userDefaults.synchronize()
    }
  }

  init() {
    userDefaults = NSUserDefaults.standardUserDefaults()
  }

  func addStock(stock: SNStock) {
    var watchlist = self.watchlist
    watchlist.append(stock)
    self.watchlist = watchlist
  }

  func removeStock(stock: SNStock) {
    var watchlist = self.watchlist
    if let index = find(watchlist, stock) {
      watchlist.removeAtIndex(index)
      self.watchlist = watchlist
    }
  }

}

Remember that your object needs to implement NSCoding or else the encoding won't work. Here is what SNStock looks like:

import Foundation

class SNStock: NSObject, NSCoding
{
  let ticker: NSString
  let name: NSString

  init(ticker: NSString, name: NSString)
  {
    self.ticker = ticker
    self.name = name
  }

  //MARK: NSCoding

  required init(coder aDecoder: NSCoder) {
    self.ticker = aDecoder.decodeObjectForKey("ticker") as! NSString
    self.name = aDecoder.decodeObjectForKey("name") as! NSString
  }

  func encodeWithCoder(aCoder: NSCoder) {
    aCoder.encodeObject(ticker, forKey: "ticker")
    aCoder.encodeObject(name, forKey: "name")
  }

  //MARK: NSObjectProtocol

  override func isEqual(object: AnyObject?) -> Bool {
    if let object = object as? SNStock {
      return self.ticker == object.ticker &&
        self.name == object.name
    } else {
      return false
    }
  }

  override var hash: Int {
    return ticker.hashValue
  }
}

Hope this helps!

What is the most efficient way to create HTML elements using jQuery?

Someone has already made a benchmark: jQuery document.createElement equivalent?

$(document.createElement('div')) is the big winner.

Calculating distance between two points, using latitude longitude?

Here's a Java function that calculates the distance between two lat/long points, posted below, just in case it disappears again.

    private double distance(double lat1, double lon1, double lat2, double lon2, char unit) {
      double theta = lon1 - lon2;
      double dist = Math.sin(deg2rad(lat1)) * Math.sin(deg2rad(lat2)) + Math.cos(deg2rad(lat1)) * Math.cos(deg2rad(lat2)) * Math.cos(deg2rad(theta));
      dist = Math.acos(dist);
      dist = rad2deg(dist);
      dist = dist * 60 * 1.1515;
      if (unit == 'K') {
        dist = dist * 1.609344;
      } else if (unit == 'N') {
        dist = dist * 0.8684;
        }
      return (dist);
    }
    
    /*:::::::::::::::::::::::::::::::::::::::::::::::::::::::::::::::::::*/
    /*::  This function converts decimal degrees to radians             :*/
    /*:::::::::::::::::::::::::::::::::::::::::::::::::::::::::::::::::::*/
    private double deg2rad(double deg) {
      return (deg * Math.PI / 180.0);
    }
    
    /*:::::::::::::::::::::::::::::::::::::::::::::::::::::::::::::::::::*/
    /*::  This function converts radians to decimal degrees             :*/
    /*:::::::::::::::::::::::::::::::::::::::::::::::::::::::::::::::::::*/
    private double rad2deg(double rad) {
      return (rad * 180.0 / Math.PI);
    }
    
    System.out.println(distance(32.9697, -96.80322, 29.46786, -98.53506, 'M') + " Miles\n");
    System.out.println(distance(32.9697, -96.80322, 29.46786, -98.53506, 'K') + " Kilometers\n");
    System.out.println(distance(32.9697, -96.80322, 29.46786, -98.53506, 'N') + " Nautical Miles\n");

Convert bytes to bits in python

input_str = "ABC"
[bin(byte) for byte in bytes(input_str, "utf-8")]

Will give:

['0b1000001', '0b1000010', '0b1000011']

How to get data from database in javascript based on the value passed to the function

The error is coming as your query is getting formed as

SELECT * FROM Employ where number = parseInt(val);

I dont know which DB you are using but no DB will understand parseInt.

What you can do is use a variable say temp and store the value of parseInt(val) in temp variable and make the query as

SELECT * FROM Employ where number = temp;

How can I use the MS JDBC driver with MS SQL Server 2008 Express?

You have the wrong URL.

I don't know what you mean by "JDBC 2005". When I looked on the microsoft site, I found something called the Microsoft SQL Server JDBC Driver 2.0. You're going to want that one - it includes lots of fixes and some perf improvements. [edit: you're probably going to want the latest driver. As of March 2012, the latest JDBC driver from Microsoft is JDBC 4.0]

Check the release notes. For this driver, you want:

URL:  jdbc:sqlserver://server:port;DatabaseName=dbname
Class name: com.microsoft.sqlserver.jdbc.SQLServerDriver

It seems you have the class name correct, but the URL wrong.

Microsoft changed the class name and the URL after its initial release of a JDBC driver. The URL you are using goes with the original JDBC driver from Microsoft, the one MS calls the "SQL Server 2000 version". But that driver uses a different classname.

For all subsequent drivers, the URL changed to the form I have here.

This is in the release notes for the JDBC driver.

How to set page content to the middle of screen?

I'm guessing you want to center the box both vertically and horizontally, regardless of browser window size. Since you have a fixed width and height for the box, this should work:

Markup:

<div></div>

CSS:

div {
    height: 200px;
    width: 400px;
    background: black;

    position: fixed;
    top: 50%;
    left: 50%;
    margin-top: -100px;
    margin-left: -200px;
}

The div should remain in the center of the screen even if you resize the browser. Just replace the margin-top and margin-left with half of the height and width of your table.

Edit: Credit goes to CSS-Tricks, where I got the original idea.

Extension mysqli is missing, phpmyadmin doesn't work

I have encountered the same error on ubuntu and what worked for me was editing 2 lines in /etc/php/7.3/apache2/php.ini

  ;extension=mysqli to   extension=mysqli

and gave the extension variable location to mysqli.so after uncommenting it

   extension=/usr/lib/php/20170718/mysqli.so

then restart the service just to make sure

systemctl start mysql

Can the "IN" operator use LIKE-wildcards (%) in Oracle?

This appears to fit what you are looking for: https://forums.oracle.com/forums/thread.jspa?threadID=2140801

Basically, you will need to use regular expressions as there appears to be nothing built into oracle for this.

I pulled out the example from the thread and converted it for your purposes. I suck at regex's, though, so that might need tweaked :)

SELECT  *
FROM myTable m
WHERE NOT regexp_like(m.status,'((Done^|Finished except^|In Progress^)')

How to track untracked content?

  1. I removed the .git directories from those new directories (this can create submodule drama. Google it if interested.)
  2. I then ran git rm -rf --cached /the/new/directories
  3. Then I re-added the directories with a git add . from above

Reference URL https://danielmiessler.com/blog/git-modified-untracked/#gs.W0C7X6U

Python 3.1.1 string to hex

binascii methodes are easier by the way

>>> import binascii
>>> x=b'test'
>>> x=binascii.hexlify(x)
>>> x
b'74657374'
>>> y=str(x,'ascii')
>>> y
'74657374'
>>> x=binascii.unhexlify(x)
>>> x
b'test'
>>> y=str(x,'ascii')
>>> y
'test'

Hope it helps. :)

How to make a stable two column layout in HTML/CSS

I could care less about IE6, as long as it works in IE8, Firefox 4, and Safari 5

This makes me happy.

Try this: Live Demo

display: table is surprisingly good. Once you don't care about IE7, you're free to use it. It doesn't really have any of the usual downsides of <table>.

CSS:

#container {
    background: #ccc;
    display: table
}
#left, #right {
    display: table-cell
}
#left {
    width: 150px;
    background: #f0f;
    border: 5px dotted blue;
}
#right {
    background: #aaa;
    border: 3px solid #000
}

no sqljdbc_auth in java.library.path

1) Download the JDBC Driver here.


2) unzip the file and go to sqljdbc_version\fra\auth\x86 or \x64
3) copy the sqljdbc_auth.dll to C:\Program Files\Java\jre_Version\bin
4) Finally restart eclipse

Is it possible to GROUP BY multiple columns using MySQL?

Yes, but what does grouping by more two columns mean? Well, it's the same as grouping by each unique pair per row. The order you list the columns changes the way the rows are sorted.

In your example, you would write

GROUP BY fV.tier_id, f.form_template_id

Meanwhile, the code

GROUP BY f.form_template_id, fV.tier_id

would give similar results, but sorted differently.

Uses of content-disposition in an HTTP response header

This header is defined in RFC 2183, so that would be the best place to start reading.

Permitted values are those registered with the Internet Assigned Numbers Authority (IANA); their registry of values should be seen as the definitive source.

What does -save-dev mean in npm install grunt --save-dev

For me the first answer appears a bit confusing, so to make it short and clean:

npm install <package_name> saves any specified packages into dependencies by default. Additionally, you can control where and how they get saved with some additional flags:

npm install <package_name> --no-save Prevents saving to dependencies.

npm install <package_name> ---save-dev updates the devDependencies in your package. These are only used for local testing and development.

You can read more at in the dcu

How can I get zoom functionality for images?

This is a very late addition to this thread but I've been working on an image view that supports zoom and pan and has a couple of features I haven't found elsewhere. This started out as a way of displaying very large images without causing OutOfMemoryErrors, by subsampling the image when zoomed out and loading higher resolution tiles when zoomed in. It now supports use in a ViewPager, rotation manually or using EXIF information (90° stops), override of selected touch events using OnClickListener or your own GestureDetector or OnTouchListener, subclassing to add overlays, pan while zooming, and fling momentum.

It's not intended as a general use replacement for ImageView so doesn't extend it, and doesn't support display of images from resources, only assets and external files. It requires SDK 10.

Source is on GitHub, and there's a sample that illustrates use in a ViewPager.

https://github.com/davemorrissey/subsampling-scale-image-view

Saving an Excel sheet in a current directory with VBA

If the Path is omitted the file will be saved automaticaly in the current directory. Try something like this:

ActiveWorkbook.SaveAs "Filename.xslx"

How to find indices of all occurrences of one string in another in JavaScript?

I would recommend Tim's answer. However, this comment by @blazs states "Suppose searchStr=aaa and that str=aaaaaa. Then instead of finding 4 occurences your code will find only 2 because you're making skips by searchStr.length in the loop.", which is true by looking at Tim's code, specifically this line here: startIndex = index + searchStrLen; Tim's code would not be able to find an instance of the string that's being searched that is within the length of itself. So, I've modified Tim's answer:

_x000D_
_x000D_
function getIndicesOf(searchStr, str, caseSensitive) {
    var startIndex = 0, index, indices = [];
    if (!caseSensitive) {
        str = str.toLowerCase();
        searchStr = searchStr.toLowerCase();
    }
    while ((index = str.indexOf(searchStr, startIndex)) > -1) {
        indices.push(index);
        startIndex = index + 1;
    }
    return indices;
}
var searchStr = prompt("Enter a string.");
var str = prompt("What do you want to search for in the string?");
var indices = getIndicesOf(str, searchStr);

document.getElementById("output").innerHTML = indices + "";
_x000D_
<div id="output"></div>
_x000D_
_x000D_
_x000D_

Changing it to + 1 instead of + searchStrLen will allow the index 1 to be in the indices array if I have an str of aaaaaa and a searchStr of aaa.

P.S. If anyone would like comments in the code to explain how the code works, please say so, and I'll be happy to respond to the request.

What is the difference between the remap, noremap, nnoremap and vnoremap mapping commands in Vim?

One difference is that:

  • :map does nvo == normal + (visual + select) + operator pending
  • :map! does ic == insert + command-line mode

as stated on help map-modes tables.

So: map does not map to all modes.

To map to all modes you need both :map and :map!.

PostgreSQL: FOREIGN KEY/ON DELETE CASCADE

A foreign key with a cascade delete means that if a record in the parent table is deleted, then the corresponding records in the child table will automatically be deleted. This is called a cascade delete.

You are saying in a opposite way, this is not that when you delete from child table then records will be deleted from parent table.

UPDATE 1:

ON DELETE CASCADE option is to specify whether you want rows deleted in a child table when corresponding rows are deleted in the parent table. If you do not specify cascading deletes, the default behaviour of the database server prevents you from deleting data in a table if other tables reference it.

If you specify this option, later when you delete a row in the parent table, the database server also deletes any rows associated with that row (foreign keys) in a child table. The principal advantage to the cascading-deletes feature is that it allows you to reduce the quantity of SQL statements you need to perform delete actions.

So it's all about what will happen when you delete rows from Parent table not from child table.

So in your case when user removes entries from CATs table then rows will be deleted from books table. :)

Hope this helps you :)

Mapping many-to-many association table with extra column(s)

I search a way to map a many-to-many association table with extra column(s) with hibernate in xml files configuration.

Assuming with have two table 'a' & 'c' with a many to many association with a column named 'extra'. Cause I didn't find any complete example, here is my code. Hope it will help :).

First here is the Java objects.

public class A implements Serializable{  

    protected int id;
    // put some others fields if needed ...   
    private Set<AC> ac = new HashSet<AC>();

    public A(int id) {
        this.id = id;
    }

    public int getId() {
        return id;
    }

    public void setId(int id) {
        this.id = id;
    }

    public Set<AC> getAC() {
        return ac;
    }

    public void setAC(Set<AC> ac) {
        this.ac = ac;
    }

    /** {@inheritDoc} */
    @Override
    public int hashCode() {
        final int prime = 97;
        int result = 1;
        result = prime * result + id;
        return result;
    }

    /** {@inheritDoc} */
    @Override
    public boolean equals(Object obj) {
        if (this == obj)
            return true;
        if (obj == null)
            return false;
        if (!(obj instanceof A))
            return false;
        final A other = (A) obj;
        if (id != other.getId())
            return false;
        return true;
    }

}

public class C implements Serializable{

    protected int id;
    // put some others fields if needed ...    

    public C(int id) {
        this.id = id;
    }

    public int getId() {
        return id;
    }

    public void setId(int id) {
        this.id = id;
    }

    /** {@inheritDoc} */
    @Override
    public int hashCode() {
        final int prime = 98;
        int result = 1;
        result = prime * result + id;
        return result;
    }

    /** {@inheritDoc} */
    @Override
    public boolean equals(Object obj) {
        if (this == obj)
            return true;
        if (obj == null)
            return false;
        if (!(obj instanceof C))
            return false;
        final C other = (C) obj;
        if (id != other.getId())
            return false;
        return true;
    }

}

Now, we have to create the association table. The first step is to create an object representing a complex primary key (a.id, c.id).

public class ACId implements Serializable{

    private A a;
    private C c;

    public ACId() {
        super();
    }

    public A getA() {
        return a;
    }
    public void setA(A a) {
        this.a = a;
    }
    public C getC() {
        return c;
    }
    public void setC(C c) {
        this.c = c;
    }
    @Override
    public int hashCode() {
        final int prime = 31;
        int result = 1;
        result = prime * result + ((a == null) ? 0 : a.hashCode());
        result = prime * result
                + ((c == null) ? 0 : c.hashCode());
        return result;
    }
    @Override
    public boolean equals(Object obj) {
        if (this == obj)
            return true;
        if (obj == null)
            return false;
        if (getClass() != obj.getClass())
            return false;
        ACId other = (ACId) obj;
        if (a == null) {
            if (other.a != null)
                return false;
        } else if (!a.equals(other.a))
            return false;
        if (c == null) {
            if (other.c != null)
                return false;
        } else if (!c.equals(other.c))
            return false;
        return true;
    }
}

Now let's create the association object itself.

public class AC implements java.io.Serializable{

    private ACId id = new ACId();
    private String extra;

    public AC(){

    }

    public ACId getId() {
        return id;
    }

    public void setId(ACId id) {
        this.id = id;
    }

    public A getA(){
        return getId().getA();
    }

    public C getC(){
        return getId().getC();
    }

    public void setC(C C){
        getId().setC(C);
    }

    public void setA(A A){
        getId().setA(A);
    }

    public String getExtra() {
        return extra;
    }

    public void setExtra(String extra) {
        this.extra = extra;
    }

    public boolean equals(Object o) {
        if (this == o)
            return true;
        if (o == null || getClass() != o.getClass())
            return false;

        AC that = (AC) o;

        if (getId() != null ? !getId().equals(that.getId())
                : that.getId() != null)
            return false;

        return true;
    }

    public int hashCode() {
        return (getId() != null ? getId().hashCode() : 0);
    }
}

At this point, it's time to map all our classes with hibernate xml configuration.

A.hbm.xml and C.hxml.xml (quiete the same).

<class name="A" table="a">
        <id name="id" column="id_a" unsaved-value="0">
            <generator class="identity">
                <param name="sequence">a_id_seq</param>
            </generator>
        </id>
<!-- here you should map all others table columns -->
<!-- <property name="otherprop" column="otherprop" type="string" access="field" /> -->
    <set name="ac" table="a_c" lazy="true" access="field" fetch="select" cascade="all">
        <key>
            <column name="id_a" not-null="true" />
        </key>
        <one-to-many class="AC" />
    </set>
</class>

<class name="C" table="c">
        <id name="id" column="id_c" unsaved-value="0">
            <generator class="identity">
                <param name="sequence">c_id_seq</param>
            </generator>
        </id>
</class>

And then association mapping file, a_c.hbm.xml.

<class name="AC" table="a_c">
    <composite-id name="id" class="ACId">
        <key-many-to-one name="a" class="A" column="id_a" />
        <key-many-to-one name="c" class="C" column="id_c" />
    </composite-id>
    <property name="extra" type="string" column="extra" />
</class>

Here is the code sample to test.

A = ADao.get(1);
C = CDao.get(1);

if(A != null && C != null){
    boolean exists = false;
            // just check if it's updated or not
    for(AC a : a.getAC()){
        if(a.getC().equals(c)){
            // update field
            a.setExtra("extra updated");
            exists = true;
            break;
        }
    }

    // add 
    if(!exists){
        ACId idAC = new ACId();
        idAC.setA(a);
        idAC.setC(c);

        AC AC = new AC();
        AC.setId(idAC);
        AC.setExtra("extra added"); 
        a.getAC().add(AC);
    }

    ADao.save(A);
}

AttributeError: 'list' object has no attribute 'encode'

You need to do encode on tmp[0], not on tmp.

tmp is not a string. It contains a (Unicode) string.

Try running type(tmp) and print dir(tmp) to see it for yourself.

How to force a checkbox and text on the same line?

Another way to do this solely with css:

input[type='checkbox'] {
  float: left;
  width: 20px;
}
input[type='checkbox'] + label {
  display: block;
  width: 30px;
}

Note that this forces each checkbox and its label onto a separate line, rather than only doing so only when there's overflow.

How to auto-format code in Eclipse?

Another option is to go to Window->Preferences->Java->Editor->SaveActions and check the Format source code option. Then your source code will be formatted truly automatically each time you save it.

Using Address Instead Of Longitude And Latitude With Google Maps API

See this example, initializes the map to "San Diego, CA".

Uses the Google Maps Javascript API v3 Geocoder to translate the address into coordinates that can be displayed on the map.

<html>
<head>
<meta name="viewport" content="initial-scale=1.0, user-scalable=no"/>
<meta http-equiv="content-type" content="text/html; charset=UTF-8"/>
<title>Google Maps JavaScript API v3 Example: Geocoding Simple</title>
<script type="text/javascript" src="http://maps.google.com/maps/api/js?sensor=false"></script>
<script type="text/javascript">
  var geocoder;
  var map;
  var address ="San Diego, CA";
  function initialize() {
    geocoder = new google.maps.Geocoder();
    var latlng = new google.maps.LatLng(-34.397, 150.644);
    var myOptions = {
      zoom: 8,
      center: latlng,
    mapTypeControl: true,
    mapTypeControlOptions: {style: google.maps.MapTypeControlStyle.DROPDOWN_MENU},
    navigationControl: true,
      mapTypeId: google.maps.MapTypeId.ROADMAP
    };
    map = new google.maps.Map(document.getElementById("map_canvas"), myOptions);
    if (geocoder) {
      geocoder.geocode( { 'address': address}, function(results, status) {
        if (status == google.maps.GeocoderStatus.OK) {
          if (status != google.maps.GeocoderStatus.ZERO_RESULTS) {
          map.setCenter(results[0].geometry.location);

            var infowindow = new google.maps.InfoWindow(
                { content: '<b>'+address+'</b>',
                  size: new google.maps.Size(150,50)
                });
    
            var marker = new google.maps.Marker({
                position: results[0].geometry.location,
                map: map, 
                title:address
            }); 
            google.maps.event.addListener(marker, 'click', function() {
                infowindow.open(map,marker);
            });

          } else {
            alert("No results found");
          }
        } else {
          alert("Geocode was not successful for the following reason: " + status);
        }
      });
    }
  }
</script>
</head>
<body style="margin:0px; padding:0px;" onload="initialize()">
 <div id="map_canvas" style="width:100%; height:100%">
</body>
</html>

working code snippet:

_x000D_
_x000D_
var geocoder;
var map;
var address = "San Diego, CA";

function initialize() {
  geocoder = new google.maps.Geocoder();
  var latlng = new google.maps.LatLng(-34.397, 150.644);
  var myOptions = {
    zoom: 8,
    center: latlng,
    mapTypeControl: true,
    mapTypeControlOptions: {
      style: google.maps.MapTypeControlStyle.DROPDOWN_MENU
    },
    navigationControl: true,
    mapTypeId: google.maps.MapTypeId.ROADMAP
  };
  map = new google.maps.Map(document.getElementById("map_canvas"), myOptions);
  if (geocoder) {
    geocoder.geocode({
      'address': address
    }, function(results, status) {
      if (status == google.maps.GeocoderStatus.OK) {
        if (status != google.maps.GeocoderStatus.ZERO_RESULTS) {
          map.setCenter(results[0].geometry.location);

          var infowindow = new google.maps.InfoWindow({
            content: '<b>' + address + '</b>',
            size: new google.maps.Size(150, 50)
          });

          var marker = new google.maps.Marker({
            position: results[0].geometry.location,
            map: map,
            title: address
          });
          google.maps.event.addListener(marker, 'click', function() {
            infowindow.open(map, marker);
          });

        } else {
          alert("No results found");
        }
      } else {
        alert("Geocode was not successful for the following reason: " + status);
      }
    });
  }
}
google.maps.event.addDomListener(window, 'load', initialize);
_x000D_
html,
body,
#map_canvas {
  height: 100%;
  width: 100%;
}
_x000D_
<script type="text/javascript" src="https://maps.google.com/maps/api/js?key=AIzaSyCkUOdZ5y7hMm0yrcCQoCvLwzdM6M8s5qk"></script>
<div id="map_canvas" ></div>
_x000D_
_x000D_
_x000D_

How to fix missing dependency warning when using useEffect React Hook?

Add this comment on the top of your file to disable warning.

/* eslint-disable react-hooks/exhaustive-deps */

Does Python have a package/module management system?

On Windows install http://chocolatey.org/ then

choco install python

Open a new cmd-window with the updated PATH. Next, do

choco install pip

After that you can

pip install pyside
pip install ipython
...

String.equals versus ==

== operator compares the reference of an object in Java. You can use string's equals method .

String s = "Test";
if(s.equals("Test"))
{
    System.out.println("Equal");
}

Is there a way to cast float as a decimal without rounding and preserving its precision?

Have you tried:

SELECT Cast( 2.555 as decimal(53,8))

This would return 2.55500000. Is that what you want?

UPDATE:

Apparently you can also use SQL_VARIANT_PROPERTY to find the precision and scale of a value. Example:

SELECT SQL_VARIANT_PROPERTY(Cast( 2.555 as decimal(8,7)),'Precision'),
SQL_VARIANT_PROPERTY(Cast( 2.555 as decimal(8,7)),'Scale')

returns 8|7

You may be able to use this in your conversion process...

Copying data from one SQLite database to another

If you use DB Browser for SQLite, you can copy the table from one db to another in following steps:

  1. Open two instances of the app and load the source db and target db side by side.
  2. If the target db does not have the table, "Copy Create Statement" from the source db and then paste the sql statement in "Execute SQL" tab and run the sql to create the table.
  3. In the source db, export the table as a CSV file.
  4. In the target db, import the CSV file to the table with the same table name. The app will ask you do you want to import the data to the existing table, click yes. Done.

What is (functional) reactive programming?

I found this nice video on the Clojure subreddit about FRP. It is pretty easy to understand even if you don't know Clojure.

Here's the video: http://www.youtube.com/watch?v=nket0K1RXU4

Here's the source the video refers to in the 2nd half: https://github.com/Cicayda/yolk-examples/blob/master/src/yolk_examples/client/autocomplete.cljs

Stacked Tabs in Bootstrap 3

Left, Right and Below tabs were removed from Bootstrap 3, but you can add custom CSS to achieve this..

.tabs-below > .nav-tabs,
.tabs-right > .nav-tabs,
.tabs-left > .nav-tabs {
  border-bottom: 0;
}

.tab-content > .tab-pane,
.pill-content > .pill-pane {
  display: none;
}

.tab-content > .active,
.pill-content > .active {
  display: block;
}

.tabs-below > .nav-tabs {
  border-top: 1px solid #ddd;
}

.tabs-below > .nav-tabs > li {
  margin-top: -1px;
  margin-bottom: 0;
}

.tabs-below > .nav-tabs > li > a {
  -webkit-border-radius: 0 0 4px 4px;
     -moz-border-radius: 0 0 4px 4px;
          border-radius: 0 0 4px 4px;
}

.tabs-below > .nav-tabs > li > a:hover,
.tabs-below > .nav-tabs > li > a:focus {
  border-top-color: #ddd;
  border-bottom-color: transparent;
}

.tabs-below > .nav-tabs > .active > a,
.tabs-below > .nav-tabs > .active > a:hover,
.tabs-below > .nav-tabs > .active > a:focus {
  border-color: transparent #ddd #ddd #ddd;
}

.tabs-left > .nav-tabs > li,
.tabs-right > .nav-tabs > li {
  float: none;
}

.tabs-left > .nav-tabs > li > a,
.tabs-right > .nav-tabs > li > a {
  min-width: 74px;
  margin-right: 0;
  margin-bottom: 3px;
}

.tabs-left > .nav-tabs {
  float: left;
  margin-right: 19px;
  border-right: 1px solid #ddd;
}

.tabs-left > .nav-tabs > li > a {
  margin-right: -1px;
  -webkit-border-radius: 4px 0 0 4px;
     -moz-border-radius: 4px 0 0 4px;
          border-radius: 4px 0 0 4px;
}

.tabs-left > .nav-tabs > li > a:hover,
.tabs-left > .nav-tabs > li > a:focus {
  border-color: #eeeeee #dddddd #eeeeee #eeeeee;
}

.tabs-left > .nav-tabs .active > a,
.tabs-left > .nav-tabs .active > a:hover,
.tabs-left > .nav-tabs .active > a:focus {
  border-color: #ddd transparent #ddd #ddd;
  *border-right-color: #ffffff;
}

.tabs-right > .nav-tabs {
  float: right;
  margin-left: 19px;
  border-left: 1px solid #ddd;
}

.tabs-right > .nav-tabs > li > a {
  margin-left: -1px;
  -webkit-border-radius: 0 4px 4px 0;
     -moz-border-radius: 0 4px 4px 0;
          border-radius: 0 4px 4px 0;
}

.tabs-right > .nav-tabs > li > a:hover,
.tabs-right > .nav-tabs > li > a:focus {
  border-color: #eeeeee #eeeeee #eeeeee #dddddd;
}

.tabs-right > .nav-tabs .active > a,
.tabs-right > .nav-tabs .active > a:hover,
.tabs-right > .nav-tabs .active > a:focus {
  border-color: #ddd #ddd #ddd transparent;
  *border-left-color: #ffffff;
}

Working example: http://bootply.com/74926

UPDATE

If you don't need the exact look of a tab (bordered appropriately on the left or right as each tab is activated), you can simple use nav-stacked, along with Bootstrap col-* to float the tabs to the left or right...

nav-stacked demo: http://codeply.com/go/rv3Cvr0lZ4

<ul class="nav nav-pills nav-stacked col-md-3">
    <li><a href="#a" data-toggle="tab">1</a></li>
    <li><a href="#b" data-toggle="tab">2</a></li>
    <li><a href="#c" data-toggle="tab">3</a></li>
</ul>

TypeScript-'s Angular Framework Error - "There is no directive with exportAs set to ngForm"

In addition to import the form module in login component ts file you need to import NgForm also.

import { NgForm } from '@angular/forms';

This resolved my issue

window.location.href and window.open () methods in JavaScript

window.location.href is not a method, it's a property that will tell you the current URL location of the browser. Changing the value of the property will redirect the page.

window.open() is a method that you can pass a URL to that you want to open in a new window. For example:

window.location.href example:

window.location.href = 'http://www.google.com'; //Will take you to Google.

window.open() example:

window.open('http://www.google.com'); //This will open Google in a new window.

Additional Information:

window.open() can be passed additional parameters. See: window.open tutorial

Downloading a picture via urllib and python

Using urllib, you can get this done instantly.

import urllib.request

opener=urllib.request.build_opener()
opener.addheaders=[('User-Agent','Mozilla/5.0 (Windows NT 6.1; WOW64) AppleWebKit/537.36 (KHTML, like Gecko) Chrome/36.0.1941.0 Safari/537.36')]
urllib.request.install_opener(opener)

urllib.request.urlretrieve(URL, "images/0.jpg")

How to create a JSON object

Although the other answers posted here work, I find the following approach more natural:

$obj = (object) [
    'aString' => 'some string',
    'anArray' => [ 1, 2, 3 ]
];

echo json_encode($obj);

Changing image size in Markdown

When using Flask (I am using it with flat pages)... I found that enabling explicitly (was not by default for some reason) 'attr_list' in extensions within the call to markdown does the trick - and then one can use the attributes (very useful also to access CSS - class="my class" for example...).

FLATPAGES_HTML_RENDERER = prerender_jinja

and the function:

def prerender_jinja(text):
    prerendered_body = render_template_string(Markup(text))
    pygmented_body   = markdown.markdown(prerendered_body, extensions=['codehilite', 'fenced_code', 'tables', 'attr_list'])
    return pygmented_body

And then in Markdown:

![image](https://octodex.github.com/images/yaktocat.png "This is a tooltip"){: width=200px}

How to change a string into uppercase

s = 'sdsd'
print (s.upper())
upper = raw_input('type in something lowercase.')
lower = raw_input('type in the same thing caps lock.')
print upper.upper()
print lower.lower()

What is an OS kernel ? How does it differ from an operating system?

A kernel is the part of the operating system that mediates access to system resources. It's responsible for enabling multiple applications to effectively share the hardware by controlling access to CPU, memory, disk I/O, and networking.

An operating system is the kernel plus applications that enable users to get something done (i.e compiler, text editor, window manager, etc).

Simplest way to set image as JPanel background

Draw the image on the background of a JPanel that is added to the frame. Use a layout manager to normally add your buttons and other components to the panel. If you add other child panels, perhaps you want to set child.setOpaque(false).

import javax.imageio.ImageIO;
import javax.swing.*;
import java.awt.*;
import java.io.IOException;
import java.net.URL;

public class BackgroundImageApp {
    private JFrame frame;

    private BackgroundImageApp create() {
        frame = createFrame();
        frame.getContentPane().add(createContent());

        return this;
    }

    private JFrame createFrame() {
        JFrame frame = new JFrame(getClass().getName());
        frame.setDefaultCloseOperation(WindowConstants.EXIT_ON_CLOSE);

        return frame;
    }

    private void show() {
        frame.pack();
        frame.setLocationRelativeTo(null);
        frame.setVisible(true);
    }

    private Component createContent() {
        final Image image = requestImage();

        JPanel panel = new JPanel() {
            @Override
            protected void paintComponent(Graphics g) {
                super.paintComponent(g);
                g.drawImage(image, 0, 0, null);
            }
        };

        panel.setLayout(new BoxLayout(panel, BoxLayout.Y_AXIS));
        for (String label : new String[]{"One", "Dois", "Drei", "Quatro", "Peace"}) {
            JButton button = new JButton(label);
            button.setAlignmentX(Component.CENTER_ALIGNMENT);
            panel.add(Box.createRigidArea(new Dimension(15, 15)));
            panel.add(button);
        }

        panel.setPreferredSize(new Dimension(500, 500));

        return panel;
    }

    private Image requestImage() {
        Image image = null;

        try {
            image = ImageIO.read(new URL("http://www.johnlennon.com/wp-content/themes/jl/images/home-gallery/2.jpg"));
        } catch (IOException e) {
            e.printStackTrace();
        }

        return image;
    }

    public static void main(String[] args) {
        SwingUtilities.invokeLater(new Runnable() {
            @Override
            public void run() {
                new BackgroundImageApp().create().show();
            }
        });
    }
}

How to put a delay on AngularJS instant search?

(See answer below for a Angular 1.3 solution.)

The issue here is that the search will execute every time the model changes, which is every keyup action on an input.

There would be cleaner ways to do this, but probably the easiest way would be to switch the binding so that you have a $scope property defined inside your Controller on which your filter operates. That way you can control how frequently that $scope variable is updated. Something like this:

JS:

var App = angular.module('App', []);

App.controller('DisplayController', function($scope, $http, $timeout) {
    $http.get('data.json').then(function(result){
        $scope.entries = result.data;
    });

    // This is what you will bind the filter to
    $scope.filterText = '';

    // Instantiate these variables outside the watch
    var tempFilterText = '',
        filterTextTimeout;
    $scope.$watch('searchText', function (val) {
        if (filterTextTimeout) $timeout.cancel(filterTextTimeout);

        tempFilterText = val;
        filterTextTimeout = $timeout(function() {
            $scope.filterText = tempFilterText;
        }, 250); // delay 250 ms
    })
});

HTML:

<input id="searchText" type="search" placeholder="live search..." ng-model="searchText" />
<div class="entry" ng-repeat="entry in entries | filter:filterText">
    <span>{{entry.content}}</span>
</div>

Using C++ base class constructors?

No, that's not how it is done. Normal way to initialize the base class is in the initialization list :

class A
{
public: 
    A(int val) {}
};

class B : public A
{
public:
  B( int v) : A( v )
  {
  }
};


void main()
{
    B b(10);
}

Python: Get relative path from comparing two absolute paths

os.path.relpath:

Return a relative filepath to path either from the current directory or from an optional start point.

>>> from os.path import relpath
>>> relpath('/usr/var/log/', '/usr/var')
'log'
>>> relpath('/usr/var/log/', '/usr/var/sad/')
'../log'

So, if relative path starts with '..' - it means that the second path is not descendant of the first path.

In Python3 you can use PurePath.relative_to:

Python 3.5.1 (default, Jan 22 2016, 08:54:32)
>>> from pathlib import Path

>>> Path('/usr/var/log').relative_to('/usr/var/log/')
PosixPath('.')

>>> Path('/usr/var/log').relative_to('/usr/var/')
PosixPath('log')

>>> Path('/usr/var/log').relative_to('/etc/')
Traceback (most recent call last):
  File "<stdin>", line 1, in <module>
  File "/usr/local/Cellar/python3/3.5.1/Frameworks/Python.framework/Versions/3.5/lib/python3.5/pathlib.py", line 851, in relative_to
    .format(str(self), str(formatted)))
ValueError: '/usr/var/log' does not start with '/etc'

How to supply value to an annotation from a Constant java

Does someone know how I can use a String constant or String[] constant to supply value to an annotation?

Unfortunately, you can't do this with arrays. With non-array variables, the value must be final static.

How many times does each value appear in a column?

The quickest way would be with a pivot table. Make sure your column of data has a header row, highlight the data and the header, from the insert ribbon select pivot table and then drag your header from the pivot table fields list to the row labels and to the values boxes.

PHP expects T_PAAMAYIM_NEKUDOTAYIM?

I know Hebrew pretty well, so to clarify the name "Paamayim Nekudotayim" for you, the paraphrased meaning is "double colon", but translated literally:

  • "Paamayim" means "two" or "twice"
  • "Nekudotayim" means "dots" (lit. "holes")
    • In the Hebrew language, a nekuda means a dot.
    • The plural is nekudot, i.e, dots that act like vowels do in english.
    • The reason it why it's called Nekudo-tayim is because the suffix "-ayim" also means "two" or "twice", thus :: denotes "two times, two dots", or more commonly known as the Scope Resolution Operator.

Java: is there a map function?

This is another functional lib with which you may use map: http://code.google.com/p/totallylazy/

sequence(1, 2).map(toString); // lazily returns "1", "2"

What's the best way to dedupe a table?

I think this should require nothing more then just grouping by all columns except the id and choosing one row from every group - for simplicity just the first row, but this does not actually matter besides you have additional constraints on the id.

Or the other way around to get rid of the rows ... just delete all rows accept a single one from all groups.

Greyscale Background Css Images

Here you go:

<html xmlns="http://www.w3.org/1999/xhtml">
<head runat="server">
<title>bluantinoo CSS Grayscale Bg Image Sample</title>
<style type="text/css">
    div {
        border: 1px solid black;
        padding: 5px;
        margin: 5px;
        width: 600px;
        height: 600px;
        float: left;
        color: white;
    }
     .grayscale {
         background: url(yourimagehere.jpg);
         -moz-filter: url("data:image/svg+xml;utf8,<svg xmlns=\'http://www.w3.org/2000/svg\'><filter id=\'grayscale\'><feColorMatrix type=\'matrix\' values=\'0.3333 0.3333 0.3333 0 0 0.3333 0.3333 0.3333 0 0 0.3333 0.3333 0.3333 0 0 0 0 0 1 0\'/></filter></svg>#grayscale");
         -o-filter: url("data:image/svg+xml;utf8,<svg xmlns=\'http://www.w3.org/2000/svg\'><filter id=\'grayscale\'><feColorMatrix type=\'matrix\' values=\'0.3333 0.3333 0.3333 0 0 0.3333 0.3333 0.3333 0 0 0.3333 0.3333 0.3333 0 0 0 0 0 1 0\'/></filter></svg>#grayscale");
         -webkit-filter: grayscale(100%);
         filter: gray;
         filter: url("data:image/svg+xml;utf8,<svg xmlns=\'http://www.w3.org/2000/svg\'><filter id=\'grayscale\'><feColorMatrix type=\'matrix\' values=\'0.3333 0.3333 0.3333 0 0 0.3333 0.3333 0.3333 0 0 0.3333 0.3333 0.3333 0 0 0 0 0 1 0\'/></filter></svg>#grayscale");
     }

    .nongrayscale {
        background: url(yourimagehere.jpg);
    }
</style>
</head>
<body>
    <div class="nongrayscale">
        this is a non-grayscale of the bg image
    </div>
    <div class="grayscale">
        this is a grayscale of the bg image
    </div>
</body>
</html>

Tested it in FireFox, Chrome and IE. I've also attached an image to show my results of my implementation of this.Grayscale Background Image in DIV Sample

EDIT: Also, if you want the image to just toggle back and forth with jQuery, here's the page source for that...I've included the web link to jQuery and and image that's online so you should just be able to copy/paste to test it out:

<html xmlns="http://www.w3.org/1999/xhtml">
<head runat="server">
<title>bluantinoo CSS Grayscale Bg Image Sample</title>
<script src="http://code.jquery.com/jquery-1.11.0.min.js"></script>
<style type="text/css">
    div {
        border: 1px solid black;
        padding: 5px;
        margin: 5px;
        width: 600px;
        height: 600px;
        float: left;
        color: white;
    }
     .grayscale {
         background: url(http://www.polyrootstattoo.com/images/Artists/Buda/40.jpg);
         -moz-filter: url("data:image/svg+xml;utf8,<svg xmlns=\'http://www.w3.org/2000/svg\'><filter id=\'grayscale\'><feColorMatrix type=\'matrix\' values=\'0.3333 0.3333 0.3333 0 0 0.3333 0.3333 0.3333 0 0 0.3333 0.3333 0.3333 0 0 0 0 0 1 0\'/></filter></svg>#grayscale");
         -o-filter: url("data:image/svg+xml;utf8,<svg xmlns=\'http://www.w3.org/2000/svg\'><filter id=\'grayscale\'><feColorMatrix type=\'matrix\' values=\'0.3333 0.3333 0.3333 0 0 0.3333 0.3333 0.3333 0 0 0.3333 0.3333 0.3333 0 0 0 0 0 1 0\'/></filter></svg>#grayscale");
         -webkit-filter: grayscale(100%);
         filter: gray;
         filter: url("data:image/svg+xml;utf8,<svg xmlns=\'http://www.w3.org/2000/svg\'><filter id=\'grayscale\'><feColorMatrix type=\'matrix\' values=\'0.3333 0.3333 0.3333 0 0 0.3333 0.3333 0.3333 0 0 0.3333 0.3333 0.3333 0 0 0 0 0 1 0\'/></filter></svg>#grayscale");
     }

    .nongrayscale {
        background: url(http://www.polyrootstattoo.com/images/Artists/Buda/40.jpg);
    }
</style>
    <script type="text/javascript">
        $(document).ready(function () {
            $("#image").mouseover(function () {
                $(".nongrayscale").removeClass().fadeTo(400,0.8).addClass("grayscale").fadeTo(400, 1);
            });
            $("#image").mouseout(function () {
                $(".grayscale").removeClass().fadeTo(400, 0.8).addClass("nongrayscale").fadeTo(400, 1);
            });
        });
</script>
</head>
<body>
    <div id="image" class="nongrayscale">
        rollover this image to toggle grayscale
    </div>
</body>
</html>

EDIT 2 (For IE10-11 Users): The solution above will not work with the changes Microsoft has made to the browser as of late, so here's an updated solution that will allow you to grayscale (or desaturate) your images.

_x000D_
_x000D_
<svg>_x000D_
  <defs>_x000D_
    <filter xmlns="http://www.w3.org/2000/svg" id="desaturate">_x000D_
      <feColorMatrix type="saturate" values="0" />_x000D_
    </filter>_x000D_
  </defs>_x000D_
  <image xlink:href="http://www.polyrootstattoo.com/images/Artists/Buda/40.jpg" width="600" height="600" filter="url(#desaturate)" />_x000D_
</svg>
_x000D_
_x000D_
_x000D_

Allow anonymous authentication for a single folder in web.config?

To make it work I build my directory like this:

Project Public Restrict

So I edited my webconfig for my public folder:

<location path="Project/Public">
    <system.web>
      <authorization>
        <allow users="?"/>
      </authorization>
    </system.web>
  </location>

And for my Restricted folder:

 <location path="Project/Restricted">
    <system.web>
      <authorization>
        <allow users="*"/>
      </authorizatio>
    </system.web>
  </location>

See here for the spec of * and ?:

https://docs.microsoft.com/en-us/iis/configuration/system.webserver/security/authorization/add

I hope I have helped.

Initializing array of structures

It's called designated initializer which is introduced in C99. It's used to initialize struct or arrays, in this example, struct.

Given

struct point { 
    int x, y;
};

the following initialization

struct point p = { .y = 2, .x = 1 };

is equivalent to the C89-style

struct point p = { 1, 2 };

Send attachments with PHP Mail()?

Copying the code from this page - works in mail()

He starts off my making a function mail_attachment that can be called later. Which he does later with his attachment code.

<?php
function mail_attachment($filename, $path, $mailto, $from_mail, $from_name, $replyto, $subject, $message) {
    $file = $path.$filename;
    $file_size = filesize($file);
    $handle = fopen($file, "r");
    $content = fread($handle, $file_size);
    fclose($handle);
    $content = chunk_split(base64_encode($content));
    $uid = md5(uniqid(time()));
    $header = "From: ".$from_name." <".$from_mail.">\r\n";
    $header .= "Reply-To: ".$replyto."\r\n";
    $header .= "MIME-Version: 1.0\r\n";
    $header .= "Content-Type: multipart/mixed; boundary=\"".$uid."\"\r\n\r\n";
    $header .= "This is a multi-part message in MIME format.\r\n";
    $header .= "--".$uid."\r\n";
    $header .= "Content-type:text/plain; charset=iso-8859-1\r\n";
    $header .= "Content-Transfer-Encoding: 7bit\r\n\r\n";
    $header .= $message."\r\n\r\n";
    $header .= "--".$uid."\r\n";
    $header .= "Content-Type: application/octet-stream; name=\"".$filename."\"\r\n"; // use different content types here
    $header .= "Content-Transfer-Encoding: base64\r\n";
    $header .= "Content-Disposition: attachment; filename=\"".$filename."\"\r\n\r\n";
    $header .= $content."\r\n\r\n";
    $header .= "--".$uid."--";
    if (mail($mailto, $subject, "", $header)) {
        echo "mail send ... OK"; // or use booleans here
    } else {
        echo "mail send ... ERROR!";
    }
}

//start editing and inputting attachment details here
$my_file = "somefile.zip";
$my_path = "/your_path/to_the_attachment/";
$my_name = "Olaf Lederer";
$my_mail = "[email protected]";
$my_replyto = "[email protected]";
$my_subject = "This is a mail with attachment.";
$my_message = "Hallo,\r\ndo you like this script? I hope it will help.\r\n\r\ngr. Olaf";
mail_attachment($my_file, $my_path, "[email protected]", $my_mail, $my_name, $my_replyto, $my_subject, $my_message);
?>

He has more details on his page and answers some problems in the comments section.

What does FETCH_HEAD in Git mean?

git pull is combination of a fetch followed by a merge. When git fetch happens it notes the head commit of what it fetched in FETCH_HEAD (just a file by that name in .git) And these commits are then merged into your working directory.

How to get UTF-8 working in Java webapps?

One other point that hasn't been mentioned relates to Java Servlets working with Ajax. I have situations where a web page is picking up utf-8 text from the user sending this to a JavaScript file which includes it in a URI sent to the Servlet. The Servlet queries a database, captures the result and returns it as XML to the JavaScript file which formats it and inserts the formatted response into the original web page.

In one web app I was following an early Ajax book's instructions for wrapping up the JavaScript in constructing the URI. The example in the book used the escape() method, which I discovered (the hard way) is wrong. For utf-8 you must use encodeURIComponent().

Few people seem to roll their own Ajax these days, but I thought I might as well add this.

How do I get the resource id of an image if I know its name?

You can also try this:

try {
    Class res = R.drawable.class;
    Field field = res.getField("drawableName");
    int drawableId = field.getInt(null);
}
catch (Exception e) {
    Log.e("MyTag", "Failure to get drawable id.", e);
}

I have copied this source codes from below URL. Based on tests done in this page, it is 5 times faster than getIdentifier(). I also found it more handy and easy to use. Hope it helps you as well.

Link: Dynamically Retrieving Resources in Android

Getting min and max Dates from a pandas dataframe

'Date' is your index so you want to do,

print (df.index.min())
print (df.index.max())

2014-03-13 00:00:00
2014-03-31 00:00:00

Animate a custom Dialog

I meet the same problem,but ,at last I solve the problem by followed way

((ViewGroup)dialog.getWindow().getDecorView())
.getChildAt(0).startAnimation(AnimationUtils.loadAnimation(
context,android.R.anim.slide_in_left));

Converting a char to ASCII?

A char is an integral type. When you write

char ch = 'A';

you're setting the value of ch to whatever number your compiler uses to represent the character 'A'. That's usually the ASCII code for 'A' these days, but that's not required. You're almost certainly using a system that uses ASCII.

Like any numeric type, you can initialize it with an ordinary number:

char ch = 13;

If you want do do arithmetic on a char value, just do it: ch = ch + 1; etc.

However, in order to display the value you have to get around the assumption in the iostreams library that you want to display char values as characters rather than numbers. There are a couple of ways to do that.

std::cout << +ch << '\n';
std::cout << int(ch) << '\n'

What is the difference between a URI, a URL and a URN?

These are some very well-written but long-winded answers. Here is the difference as far as CodeIgniter is concerned:

URL - http://example.com/some/page.html

URI - /some/page.html

Put simply, URL is the full way to indentify any resource anywhere and can have different protocols like FTP, HTTP, SCP, etc.

URI is a resource on the current domain, so it needs less information to be found.

In every instance that CodeIgniter uses the word URL or URI this is the difference they are talking about, though in the grand-scheme of the web, it is not 100% correct.

How do I add space between two variables after a print in Python

print( "hello " +k+ "  " +ln);

where k and ln are variables

How to include multiple js files using jQuery $.getScript() method

There's a plugin out there that extends jQuery's getScript method. Allows for asynchronous and synchronous loading and uses jQuery's caching mechanism. Full disclosure, I wrote this. Please feel free to contribute if you find a better method.

https://github.com/hudsonfoo/jquery-getscripts

TypeError: not all arguments converted during string formatting python

In addition to the other two answers, I think the indentations are also incorrect in the last two conditions. The conditions are that one name is longer than the other and they need to start with 'elif' and with no indentations. If you put it within the first condition (by giving it four indentations from the margin), it ends up being contradictory because the lengths of the names cannot be equal and different at the same time.

    else:
        print ("The names are different, but are the same length")
elif len(name1) > len(name2):
    print ("{0} is longer than {1}".format(name1, name2))

What certificates are trusted in truststore?

Trust store generally (actually should only contain root CAs but this rule is violated in general) contains the certificates that of the root CAs (public CAs or private CAs). You can verify the list of certs in trust store using

keytool -list -v -keystore truststore.jks

Error:Unknown host services.gradle.org. You may need to adjust the proxy settings in Gradle

Preferences --> Build, Execution, Deployment --> Gradle --> Android studio

jQuery/JavaScript to replace broken images

Better call using

jQuery(window).load(function(){
    $.imgReload();
});

Because using document.ready doesn't necessary imply that images are loaded, only the HTML. Thus, there is no need for a delayed call.

How to populate/instantiate a C# array with a single value?

I realize I'm late to the party but here's an idea. Write a wrapper which has conversion operators to and from the wrapped value so that it can be used as a stand-in for the wrapped type. This was actually inspired by the silly-sounding answer from @l33t.

First (coming from C++) I realized that in C# a default ctor is not called when the elements of an array are constructed. Instead -- even in the presence of a user-defined default constructor! -- all array elements are zero-initialized. That did surprise me.

So a wrapper class which simply provides a default ctor with the desired value would work for arrays in C++ but not in C#. A workaround is to let the wrapper type map 0 to the desired seed value upon conversion. That way zero initialized values appear to be initialized with the seed for all practical purposes:

public struct MyBool
{
    private bool _invertedValue;

    public MyBool(bool b) 
    {   
        _invertedValue = !b;
    }

    public static implicit operator MyBool(bool b)
    {
        return new MyBool(b);
    }

    public static implicit operator bool(MyBool mb)
    {
        return !mb._invertedValue;
    }

}

static void Main(string[] args)
{
        MyBool mb = false; // should expose false.
        Console.Out.WriteLine("false init gives false: " 
                              + !mb);

        MyBool[] fakeBoolArray = new MyBool[100];

        Console.Out.WriteLine("Default array elems are true: " 
                              + fakeBoolArray.All(b => b) );

        fakeBoolArray[21] = false;
        Console.Out.WriteLine("Assigning false worked: " 
                              + !fakeBoolArray[21]);

        fakeBoolArray[21] = true;
        // Should define ToString() on a MyBool,
        // hence the !! to force bool
        Console.Out.WriteLine("Assigning true again worked: " 
                              + !!fakeBoolArray[21]);
}

This pattern is applicable to all value types. One could for example map 0 to 4 for ints if initialization with 4 was desired etc.

I'd love to make a template of it as would be possible in C++, providing the seed value as template parameter, but I understand that's not possible in C#. Or am I missing something? (Of course in C++ mapping is not necessary at all because one can provide a default ctor which will be called for array elements.)

FWIW, here's a C++ equivalent: https://ideone.com/wG8yEh .

Integer value in TextView

tv.setText(Integer.toString(intValue))

JFrame Exit on close Java

If you don't have it, the JFrame will just be disposed. The frame will close, but the app will continue to run.

CONVERT Image url to Base64

imageToBase64 = (URL) => {
    let image;
    image = new Image();
    image.crossOrigin = 'Anonymous';
    image.addEventListener('load', function() {
        let canvas = document.createElement('canvas');
        let context = canvas.getContext('2d');
        canvas.width = image.width;
        canvas.height = image.height;
        context.drawImage(image, 0, 0);
        try {
            localStorage.setItem('saved-image-example', canvas.toDataURL('image/png'));
        } catch (err) {
            console.error(err)
        }
    });
    image.src = URL;
};

imageToBase64('image URL')

How to convert Rows to Columns in Oracle?

If you are using Oracle 10g, you can use the DECODE function to pivot the rows into columns:

CREATE TABLE doc_tab (
  loan_number VARCHAR2(20),
  document_type VARCHAR2(20),
  document_id VARCHAR2(20)
);

INSERT INTO doc_tab VALUES('992452533663', 'Voters ID', 'XPD0355636');
INSERT INTO doc_tab VALUES('992452533663', 'Pan card', 'CHXPS5522D');
INSERT INTO doc_tab VALUES('992452533663', 'Drivers licence', 'DL-0420110141769');

COMMIT;

SELECT
    loan_number,
    MAX(DECODE(document_type, 'Voters ID', document_id)) AS voters_id,
    MAX(DECODE(document_type, 'Pan card', document_id)) AS pan_card,
    MAX(DECODE(document_type, 'Drivers licence', document_id)) AS drivers_licence
  FROM
    doc_tab
GROUP BY loan_number
ORDER BY loan_number;

Output:

LOAN_NUMBER   VOTERS_ID            PAN_CARD             DRIVERS_LICENCE    
------------- -------------------- -------------------- --------------------
992452533663  XPD0355636           CHXPS5522D           DL-0420110141769     

You can achieve the same using Oracle PIVOT clause, introduced in 11g:

SELECT *
  FROM doc_tab
PIVOT (
  MAX(document_id) FOR document_type IN ('Voters ID','Pan card','Drivers licence')
);

SQLFiddle example with both solutions: SQLFiddle example

Read more about pivoting here: Pivot In Oracle by Tim Hall

Could not load file or assembly CrystalDecisions.ReportAppServer.ClientDoc

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

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

Git error when trying to push -- pre-receive hook declined

I was using GitKraken and we made a local branch, then we merged two remote branches in it and then we tried to push the local branch to origin. It didn't work with the same error message.

The solution was to create the local branch and push it first to origin and then do the merge.

jQuery add blank option to top of list and make selected to existing dropdown

Solution native Javascript :

document.getElementById("theSelectId").insertBefore(new Option('', ''), document.getElementById("theSelectId").firstChild);

example : http://codepen.io/anon/pen/GprybL

jQuery scrollTop not working in Chrome but working in Firefox

 $("html, body").animate({ scrollTop: 0 }, "slow");

This CSS conflict with scroll to top so take care of this

 html, body {
         overflow-x: hidden;        
    }

How to rotate x-axis tick labels in Pandas barplot

The follows might be helpful:

# Valid font size are xx-small, x-small, small, medium, large, x-large, xx-large, larger, smaller, None

plt.xticks(
    rotation=45,
    horizontalalignment='right',
    fontweight='light',
    fontsize='medium',
)

Here is the function xticks[reference] with example and API

def xticks(ticks=None, labels=None, **kwargs):
    """
    Get or set the current tick locations and labels of the x-axis.

    Call signatures::

        locs, labels = xticks()            # Get locations and labels
        xticks(ticks, [labels], **kwargs)  # Set locations and labels

    Parameters
    ----------
    ticks : array_like
        A list of positions at which ticks should be placed. You can pass an
        empty list to disable xticks.

    labels : array_like, optional
        A list of explicit labels to place at the given *locs*.

    **kwargs
        :class:`.Text` properties can be used to control the appearance of
        the labels.

    Returns
    -------
    locs
        An array of label locations.
    labels
        A list of `.Text` objects.

    Notes
    -----
    Calling this function with no arguments (e.g. ``xticks()``) is the pyplot
    equivalent of calling `~.Axes.get_xticks` and `~.Axes.get_xticklabels` on
    the current axes.
    Calling this function with arguments is the pyplot equivalent of calling
    `~.Axes.set_xticks` and `~.Axes.set_xticklabels` on the current axes.

    Examples
    --------
    Get the current locations and labels:

        >>> locs, labels = xticks()

    Set label locations:

        >>> xticks(np.arange(0, 1, step=0.2))

    Set text labels:

        >>> xticks(np.arange(5), ('Tom', 'Dick', 'Harry', 'Sally', 'Sue'))

    Set text labels and properties:

        >>> xticks(np.arange(12), calendar.month_name[1:13], rotation=20)

    Disable xticks:

        >>> xticks([])
    """

Better way to represent array in java properties file

As user 'Skip Head' already pointed out, csv or a any table file format would be a better fitt in your case.

If it is an option for you, maybe this Table implementation might interest you.

Make DateTimePicker work as TimePicker only in WinForms

If you want to do it from properties, you can do this by setting the Format property of DateTimePicker to DateTimePickerFormat.Time and ShowUpDown property to true. Also, customFormat can be set in properties.

PHP - Redirect and send data via POST

An old post but here is how I handled it. Using newms87's method:

if($action == "redemption")
{
    if($redemptionId != "")
    {
        $results = json_decode($rewards->redeemPoints($redemptionId));

        if($results->success == true)
        {
            $redirectLocation = $GLOBALS['BASE_URL'] . 'rewards.phtml?a=redemptionComplete';
            // put results in session and redirect back to same page passing an action paraameter
            $_SESSION['post_data'] = json_encode($results);
            header("Location:" . $redirectLocation);
            exit();
        }
    }
}
elseif($action == "redemptionComplete")
{
    // if data is in session pull it and unset it.
    if(isset($_SESSION['post_data']))
    {
        $results = json_decode($_SESSION['post_data']);
        unset($_SESSION['post_data']);
    }
    // if you got here, you completed the redemption and reloaded the confirmation page. So redirect back to rewards.phtml page.
    else
    {
        $redirectLocation = $GLOBALS['BASE_URL'] . 'rewards.phtml';
        header("Location:" . $redirectLocation);
    }
}

Update records in table from CTE

Updates you make to the CTE will be cascaded to the source table.

I have had to guess at your schema slightly, but something like this should work.

;WITH T AS
(   SELECT  InvoiceNumber, 
            DocTotal, 
            SUM(Sale + VAT) OVER(PARTITION BY InvoiceNumber) AS NewDocTotal
    FROM    PEDI_InvoiceDetail
)
UPDATE  T
SET     DocTotal = NewDocTotal

Error starting Tomcat from NetBeans - '127.0.0.1*' is not recognized as an internal or external command

Assuming you are on Windows (this bug is caused by the crappy bat files escaping), It is a bug introduced in the latest versions (7.0.56 and 8.0.14) to workaround another bug. Try to remove the " around the JAVA_OPTS declaration in catalina.bat. It fixed it for me with Tomcat 7.0.56 yesterday.

In 7.0.56 in bin/catalina.bat:179 and 184

:noJuliConfig
set "JAVA_OPTS=%JAVA_OPTS% %LOGGING_CONFIG%"

..

:noJuliManager
set "JAVA_OPTS=%JAVA_OPTS% %LOGGING_MANAGER%"

to

:noJuliConfig
set JAVA_OPTS=%JAVA_OPTS% %LOGGING_CONFIG%

.. 

:noJuliManager
set JAVA_OPTS=%JAVA_OPTS% %LOGGING_MANAGER%

For your asterisk, it might only be a configuration of yours somewhere that appends it to the host declaration.

I saw this on Tomcat's bugtracker yesterday but I can't find the link again. Edit Found it! https://issues.apache.org/bugzilla/show_bug.cgi?id=56895

I hope it fixes your problem.

Android: ScrollView force to bottom

scroll.fullScroll(View.FOCUS_DOWN) will lead to the change of focus. That will bring some strange behavior when there are more than one focusable views, e.g two EditText. There is another way for this question.

    View lastChild = scrollLayout.getChildAt(scrollLayout.getChildCount() - 1);
    int bottom = lastChild.getBottom() + scrollLayout.getPaddingBottom();
    int sy = scrollLayout.getScrollY();
    int sh = scrollLayout.getHeight();
    int delta = bottom - (sy + sh);

    scrollLayout.smoothScrollBy(0, delta);

This works well.

Kotlin Extension

fun ScrollView.scrollToBottom() {
    val lastChild = getChildAt(childCount - 1)
    val bottom = lastChild.bottom + paddingBottom
    val delta = bottom - (scrollY+ height)        
    smoothScrollBy(0, delta)
}

How can I invert color using CSS?

I think the only way to handle this is to use JavaScript

Try this Invert text color of a specific element

If you do this with css3 it's only compatible with the newest browser versions.

how to loop through rows columns in excel VBA Macro

This one is similar to @Wilhelm's solution. The loop automates based on a range created by evaluating the populated date column. This was slapped together based strictly on the conversation here and screenshots.

Please note: This assumes that the headers will always be on the same row (row 8). Changing the first row of data (moving the header up/down) will cause the range automation to break unless you edit the range block to take in the header row dynamically. Other assumptions include that VOL and CAPACITY formula column headers are named "Vol" and "Cap" respectively.

Sub Loop3()

Dim dtCnt As Long
Dim rng As Range
Dim frmlas() As String

Application.ScreenUpdating = False

'The following code block sets up the formula output range
dtCnt = Sheets("Loop").Range("A1048576").End(xlUp).Row              'lowest date column populated
endHead = Sheets("Loop").Range("XFD8").End(xlToLeft).Column         'right most header populated
Set rng = Sheets("Loop").Range(Cells(9, 2), Cells(dtCnt, endHead))  'assigns range for automation

ReDim frmlas(1)      'array assigned to formula strings
    'VOL column formula
frmlas(0) = "VOL FORMULA"
    'CAPACITY column formula
frmlas(1) = "CAP FORMULA"

For i = 1 To rng.Columns.count
If rng(0, i).Value = "Vol" Then         'checks for volume formula column
    For j = 1 To rng.Rows.count
        rng(j, i).Formula= frmlas(0)    'inserts volume formula
    Next j
ElseIf rng(0, i).Value = "Cap" Then     'checks for capacity formula column
    For j = 1 To rng.Rows.count
        rng(j, i).Formula = frmlas(1)   'inserts capacity formula
    Next j
End If
Next i

Application.ScreenUpdating = True

End Sub

How to check if a json key exists?

You can try this to check wether the key exists or not:

JSONObject object = new JSONObject(jsonfile);
if (object.containskey("key")) {
  object.get("key");
  //etc. etc.
}

How do I use regular expressions in bash scripts?

You need spaces around the operator =~

i="test"
if [[ $i =~ "200[78]" ]];
then
  echo "OK"
else
  echo "not OK"
fi

Javascript add method to object

This all depends on how you're creating Foo, and how you intend to use .bar().

First, are you using a constructor-function for your object?

var myFoo = new Foo();

If so, then you can extend the Foo function's prototype property with .bar, like so:

function Foo () { /*...*/ }
Foo.prototype.bar = function () { /*...*/ };

var myFoo = new Foo();
myFoo.bar();

In this fashion, each instance of Foo now has access to the SAME instance of .bar.
To wit: .bar will have FULL access to this, but will have absolutely no access to variables within the constructor function:

function Foo () { var secret = 38; this.name = "Bob"; }
Foo.prototype.bar = function () { console.log(secret); };
Foo.prototype.otherFunc = function () { console.log(this.name); };

var myFoo = new Foo();
myFoo.otherFunc(); // "Bob";
myFoo.bar(); // error -- `secret` is undefined...
             // ...or a value of `secret` in a higher/global scope

In another way, you could define a function to return any object (not this), with .bar created as a property of that object:

function giveMeObj () {
    var private = 42,
        privateBar = function () { console.log(private); },
        public_interface = {
            bar : privateBar
        };

    return public_interface;
}

var myObj = giveMeObj();
myObj.bar(); // 42

In this fashion, you have a function which creates new objects.
Each of those objects has a .bar function created for them.
Each .bar function has access, through what is called closure, to the "private" variables within the function that returned their particular object.
Each .bar still has access to this as well, as this, when you call the function like myObj.bar(); will always refer to myObj (public_interface, in my example Foo).

The downside to this format is that if you are going to create millions of these objects, that's also millions of copies of .bar, which will eat into memory.

You could also do this inside of a constructor function, setting this.bar = function () {}; inside of the constructor -- again, upside would be closure-access to private variables in the constructor and downside would be increased memory requirements.

So the first question is:
Do you expect your methods to have access to read/modify "private" data, which can't be accessed through the object itself (through this or myObj.X)?

and the second question is: Are you making enough of these objects so that memory is going to be a big concern, if you give them each their own personal function, instead of giving them one to share?

For example, if you gave every triangle and every texture their own .draw function in a high-end 3D game, that might be overkill, and it would likely affect framerate in such a delicate system...

If, however, you're looking to create 5 scrollbars per page, and you want each one to be able to set its position and keep track of if it's being dragged, without letting every other application have access to read/set those same things, then there's really no reason to be scared that 5 extra functions are going to kill your app, assuming that it might already be 10,000 lines long (or more).

SQL Query to add a new column after an existing column in SQL Server 2005

It is a bad idea to select * from anything, period. This is why SSMS adds every field name, even if there are hundreds, instead of select *. It is extremely inefficient regardless of how large the table is. If you don't know what the fields are, its still more efficient to pull them out of the INFORMATION_SCHEMA database than it is to select *.

A better query would be:

SELECT 
 COLUMN_NAME, 
 Case 
  When DATA_TYPE In ('varchar', 'char', 'nchar', 'nvarchar', 'binary') 
  Then convert(varchar(MAX), CHARACTER_MAXIMUM_LENGTH)  
  When DATA_TYPE In ('numeric', 'int', 'smallint', 'bigint', 'tinyint') 
  Then convert(varchar(MAX), NUMERIC_PRECISION) 
  When DATA_TYPE = 'bit' 
  Then convert(varchar(MAX), 1)
  When DATA_TYPE IN ('decimal', 'float') 
  Then convert(varchar(MAX), Concat(Concat(NUMERIC_PRECISION, ', '), NUMERIC_SCALE)) 
  When DATA_TYPE IN ('date', 'datetime', 'smalldatetime', 'time', 'timestamp') 
  Then '' 
 End As DATALEN, 
 DATA_TYPE 
FROM INFORMATION_SCHEMA.COLUMNS 
Where 
 TABLE_NAME = ''

Microsoft SQL Server 2005 service fails to start

We had a similar problem recently withour running SQL 2005 servers (more specifically: The reporting services). The windows services didn't start anymore with no real error message whatsoever.

I found out that this problem was related to some KB hotfixes that have been deployed lately. For some reason those hotfixes resulted in the services taking longer than usually for starting up.

Since by default, there is a timeout that kills the service after 30 seconds when it was not able to go beyond the start methods, this was the reason why it simply terminated.

Maybe this is what you are experiencing.

Theres a work around described on Microsoft Connect (link). Although the hotfixes listed in this article didn't match the ones that have been deployed to our systems, the workaround worked for us.

How do I wait for an asynchronously dispatched block to finish?

Very primitive solution to the problem:

void (^nextOperationAfterLongOperationBlock)(void) = ^{

};

[object runSomeLongOperationAndDo:^{
    STAssert…
    nextOperationAfterLongOperationBlock();
}];

Cut off text in string after/before separator in powershell

This does work for a specific delimiter for a specific amount of characters between the delimiter. I had many issues attempting to use this in a for each loop where the position changed but the delimiter was the same. For example I was using the backslash as the delimiter and wanted to only use everything to the right of the backslash. The issue was that once the position was defined (71 characters from the beginning) it would use $pos as 71 every time regardless of where the delimiter actually was in the script. I found another method of using a delimiter and .split to break things up then used the split variable to call the sections For instance the first section was $variable[0] and the second section was $variable[1].

How to change color and font on ListView

in android 6.0 you can change the colour of text like below

holder._linear_text_active_release_pass.setBackgroundColor(ContextCompat.getColor(context, R.color.green));

mongodb group values by multiple fields

Using aggregate function like below :

[
{$group: {_id : {book : '$book',address:'$addr'}, total:{$sum :1}}},
{$project : {book : '$_id.book', address : '$_id.address', total : '$total', _id : 0}}
]

it will give you result like following :

        {
            "total" : 1,
            "book" : "book33",
            "address" : "address90"
        }, 
        {
            "total" : 1,
            "book" : "book5",
            "address" : "address1"
        }, 
        {
            "total" : 1,
            "book" : "book99",
            "address" : "address9"
        }, 
        {
            "total" : 1,
            "book" : "book1",
            "address" : "address5"
        }, 
        {
            "total" : 1,
            "book" : "book5",
            "address" : "address2"
        }, 
        {
            "total" : 1,
            "book" : "book3",
            "address" : "address4"
        }, 
        {
            "total" : 1,
            "book" : "book11",
            "address" : "address77"
        }, 
        {
            "total" : 1,
            "book" : "book9",
            "address" : "address3"
        }, 
        {
            "total" : 1,
            "book" : "book1",
            "address" : "address15"
        }, 
        {
            "total" : 2,
            "book" : "book1",
            "address" : "address2"
        }, 
        {
            "total" : 3,
            "book" : "book1",
            "address" : "address1"
        }

I didn't quite get your expected result format, so feel free to modify this to one you need.

How do I use PHP to get the current year?

strftime("%Y");

I love strftime. It's a great function for grabbing/recombining chunks of dates/times.

Plus it respects locale settings which the date function doesn't do.

Putting text in top left corner of matplotlib plot

You can use text.

text(x, y, s, fontsize=12)

text coordinates can be given relative to the axis, so the position of your text will be independent of the size of the plot:

The default transform specifies that text is in data coords, alternatively, you can specify text in axis coords (0,0 is lower-left and 1,1 is upper-right). The example below places text in the center of the axes::

text(0.5, 0.5,'matplotlib',
     horizontalalignment='center',
     verticalalignment='center',
     transform = ax.transAxes)

To prevent the text to interfere with any point of your scatter is more difficult afaik. The easier method is to set y_axis (ymax in ylim((ymin,ymax))) to a value a bit higher than the max y-coordinate of your points. In this way you will always have this free space for the text.

EDIT: here you have an example:

In [17]: from pylab import figure, text, scatter, show
In [18]: f = figure()
In [19]: ax = f.add_subplot(111)
In [20]: scatter([3,5,2,6,8],[5,3,2,1,5])
Out[20]: <matplotlib.collections.CircleCollection object at 0x0000000007439A90>
In [21]: text(0.1, 0.9,'matplotlib', ha='center', va='center', transform=ax.transAxes)
Out[21]: <matplotlib.text.Text object at 0x0000000007415B38>
In [22]:

enter image description here

The ha and va parameters set the alignment of your text relative to the insertion point. ie. ha='left' is a good set to prevent a long text to go out of the left axis when the frame is reduced (made narrower) manually.

MySQL CREATE FUNCTION Syntax

MySQL create function syntax:

DELIMITER //

CREATE FUNCTION GETFULLNAME(fname CHAR(250),lname CHAR(250))
    RETURNS CHAR(250)
    BEGIN
        DECLARE fullname CHAR(250);
        SET fullname=CONCAT(fname,' ',lname);
        RETURN fullname;
    END //

DELIMITER ;

Use This Function In Your Query

SELECT a.*,GETFULLNAME(a.fname,a.lname) FROM namedbtbl as a


SELECT GETFULLNAME("Biswarup","Adhikari") as myname;

Watch this Video how to create mysql function and how to use in your query

Create Mysql Function Video Tutorial

How do I access the HTTP request header fields via JavaScript?

This can be accessed through Javascript because it's a property of the loaded document, not of its parent.

Here's a quick example:

<script type="text/javascript">
document.write(document.referrer);
</script>

The same thing in PHP would be:

<?php echo $_SERVER["HTTP_REFERER"]; ?>

In which case do you use the JPA @JoinTable annotation?

It's the only solution to map a ManyToMany association : you need a join table between the two entities tables to map the association.

It's also used for OneToMany (usually unidirectional) associations when you don't want to add a foreign key in the table of the many side and thus keep it independent of the one side.

Search for @JoinTable in the hibernate documentation for explanations and examples.

Is there a way to make HTML5 video fullscreen?

Safari supports it through webkitEnterFullscreen.

Chrome should support it since it's WebKit also, but errors out.

Chris Blizzard of Firefox said they're coming out with their own version of fullscreen which will allow any element to go to fullscreen. e.g. Canvas

Philip Jagenstedt of Opera says they'll support it in a later release.

Yes, the HTML5 video spec says not to support fullscreen, but since users want it, and every browser is going to support it, the spec will change.

Convert JSON String to JSON Object c#

JObject defines method Parse for this:

JObject json = JObject.Parse(str);

You might want to refer to Json.NET documentation.

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

So, you need to

  1. Import external modules you want to use
  2. And make sure you have the right access modifiers on the class and methods you want to use.

In my case I had a swift file I wanted to unit test, and the unit test file was also a swift class. I made sure the access modifiers were correct, but the statement

import stMobile

(let's say that stMobile is our target name)

still did not work (I was still getting the 'No such module' error), I checked my target, and its name was indeed stMobile. So, I went to Build Settings, under packaging, and found the Product Module Name, and for some reason this was called St_Mobile, so I changed my import statement

import St_Mobile

(which is the Product Module Name), and everything worked.

So, to sum up:

  1. Check your Product Module Name and use the import statement below in you unit test class

    import myProductModuleName
    
  2. Make sure your access modifiers are correct (class level and your methods).

Combine two or more columns in a dataframe into a new column with a new name

We can use paste0:

df$combField <- paste0(df$x, df$y)

If you do not want any padding space introduced in the concatenated field. This is more useful if you are planning to use the combined field as a unique id that represents combinations of two fields.

Read file data without saving it in Flask

We simply did:

import io
from pathlib import Path

    def test_my_upload(self, accept_json):
        """Test my uploads endpoint for POST."""
        data = {
            "filePath[]": "/tmp/bin",
            "manifest[]": (io.StringIO(str(Path(__file__).parent /
                                           "path_to_file/npmlist.json")).read(),
                           'npmlist.json'),
        }
        headers = {
            'a': 'A',
            'b': 'B'
        }
        res = self.client.post(api_route_for('/test'),
                               data=data,
                               content_type='multipart/form-data',
                               headers=headers,
                               )
        assert res.status_code == 200

Convert line endings

Some options:

Using tr

tr -d '\15\32' < windows.txt > unix.txt

OR

tr -d '\r' < windows.txt > unix.txt 

Using perl

perl -p -e 's/\r$//' < windows.txt > unix.txt

Using sed

sed 's/^M$//' windows.txt > unix.txt

OR

sed 's/\r$//' windows.txt > unix.txt

To obtain ^M, you have to type CTRL-V and then CTRL-M.

mysql extract year from date format

try this code:

SELECT YEAR( str_to_date( subdateshow, '%m/%d/%Y' ) ) AS Mydate

Oracle SQL - REGEXP_LIKE contains characters other than a-z or A-Z

The ^ negates a character class:

SELECT * FROM mytable WHERE REGEXP_LIKE(column_1, '[^A-Za-z]')

How can I perform a short delay in C# without using sleep?

Sorry for awakening an old question like this. But I think what the original author wanted as an answer was:

You need to force your program to make the graphic update after you make the change to the textbox1. You can do that by invoking Update();

textBox1.Text += "\r\nThread Sleeps!";
textBox1.Update();
System.Threading.Thread.Sleep(4000);
textBox1.Text += "\r\nThread awakens!";
textBox1.Update();

Normally this will be done automatically when the thread is done. Ex, you press a button, changes are made to the text, thread dies, and then .Update() is fired and you see the changes. (I'm not an expert so I cant really tell you when its fired, but its something similar to this any way.)

In this case, you make a change, pause the thread, and then change the text again, and when the thread finally dies the .Update() is fired. This resulting in you only seeing the last change made to the text.

You would experience the same issue if you had a long execution between the text changes.

What is JNDI? What is its basic use? When is it used?

JNDI in layman's terms is basically an Interface for being able to get instances of internal/External resources such as

  javax.sql.DataSource, 
  javax.jms.Connection-Factory,
  javax.jms.QueueConnectionFactory,
  javax.jms.TopicConnectionFactory,
  javax.mail.Session, java.net.URL,
  javax.resource.cci.ConnectionFactory,

or any other type defined by a JCA resource adapter. It provides a syntax in being able to create access whether they are internal or external. i.e (comp/env in this instance means where component/environment, there are lots of other syntax):

jndiContext.lookup("java:comp/env/persistence/customerDB");

Where is Python language used?

Python is also great for scientific programs such as statistical models or physics sims. I've done monte-carlo programs and, using the VISUAL module, a 3D simulation of the Apollo mission.

how to determine size of tablespace oracle 11g

The following query can be used to detemine tablespace and other params:

select df.tablespace_name "Tablespace",
       totalusedspace "Used MB",
       (df.totalspace - tu.totalusedspace) "Free MB",
       df.totalspace "Total MB",
       round(100 * ( (df.totalspace - tu.totalusedspace)/ df.totalspace)) "Pct. Free"
  from (select tablespace_name,
               round(sum(bytes) / 1048576) TotalSpace
          from dba_data_files 
         group by tablespace_name) df,
       (select round(sum(bytes)/(1024*1024)) totalusedspace,
               tablespace_name
          from dba_segments 
         group by tablespace_name) tu
 where df.tablespace_name = tu.tablespace_name 
   and df.totalspace <> 0;

Source: https://community.oracle.com/message/1832920

For your case if you want to know the partition name and it's size just run this query:

select owner,
       segment_name,
       partition_name,
       segment_type,
       bytes / 1024/1024 "MB" 
  from dba_segments 
 where owner = <owner_name>;

Removing duplicates from rows based on specific columns in an RDD/Spark DataFrame

The below programme will help you drop duplicates on whole , or if you want to drop duplicates based on certain columns , you can even do that:

import org.apache.spark.sql.SparkSession

object DropDuplicates {
def main(args: Array[String]) {
val spark =
  SparkSession.builder()
    .appName("DataFrame-DropDuplicates")
    .master("local[4]")
    .getOrCreate()

import spark.implicits._

// create an RDD of tuples with some data
val custs = Seq(
  (1, "Widget Co", 120000.00, 0.00, "AZ"),
  (2, "Acme Widgets", 410500.00, 500.00, "CA"),
  (3, "Widgetry", 410500.00, 200.00, "CA"),
  (4, "Widgets R Us", 410500.00, 0.0, "CA"),
  (3, "Widgetry", 410500.00, 200.00, "CA"),
  (5, "Ye Olde Widgete", 500.00, 0.0, "MA"),
  (6, "Widget Co", 12000.00, 10.00, "AZ")
)
val customerRows = spark.sparkContext.parallelize(custs, 4)

// convert RDD of tuples to DataFrame by supplying column names
val customerDF = customerRows.toDF("id", "name", "sales", "discount", "state")

println("*** Here's the whole DataFrame with duplicates")

customerDF.printSchema()

customerDF.show()

// drop fully identical rows
val withoutDuplicates = customerDF.dropDuplicates()

println("*** Now without duplicates")

withoutDuplicates.show()

// drop fully identical rows
val withoutPartials = customerDF.dropDuplicates(Seq("name", "state"))

println("*** Now without partial duplicates too")

withoutPartials.show()

 }
 }

Cannot find firefox binary in PATH. Make sure firefox is installed. OS appears to be: VISTA

  1. Open Command line (Start -> Run -> type "cmd")
  2. type PATH
  3. Verify that you can see here written C:\Program Files\Mozilla Firefox15\Firefox.exe

It will be probably not here - because thats what the error says. How to fix it?

  1. Click Start
  2. Right click on "Computer" and click "Properties"
  3. In left menu Choose "Advanced system settings"
  4. Go to tab "Advanced" and click "Environment Variables..."
  5. In the window below select "Path" and click "Edit..." (Admin rights needed)
  6. Add at the end the desired path, semicolon separated
  7. Possible restart of computer needed

It his does not help then change the constructor like this:

File pathToBinary = new File("C:\\Program Files\\Mozilla Firefox15\\Firefox.exe");
FirefoxBinary ffBinary = new FirefoxBinary(pathToBinary);
FirefoxProfile firefoxProfile = new FirefoxProfile();
FirefoxDriver _driver = new FirefoxDriver(ffBinary,firefoxProfile);

Newline in JLabel

JLabel is actually capable of displaying some rudimentary HTML, which is why it is not responding to your use of the newline character (unlike, say, System.out).

If you put in the corresponding HTML and used <BR>, you would get your newlines.

HTML SELECT - Change selected option by VALUE using JavaScript

try out this....

JSFIDDEL DEMO

using javascript

?document.getElementById('sel').value = 'car';??????????

using jQuery

$('#sel').val('car');

Locating child nodes of WebElements in selenium

If you have to wait there is a method presenceOfNestedElementLocatedBy that takes the "parent" element and a locator, e.g. a By.xpath:

WebElement subNode = new WebDriverWait(driver,10).until(
    ExpectedConditions.presenceOfNestedElementLocatedBy(
        divA, By.xpath(".//div/span")
    )
);

Eclipse doesn't stop at breakpoints

Same Problem!! Easy and Fastest Solution!! Just remove All breakpoints in debug perspective and reapply breakpoint. Works like a charm!!

Is there a simple, elegant way to define singletons?

Singleton's half brother

I completely agree with staale and I leave here a sample of creating a singleton half brother:

class void:pass
a = void();
a.__class__ = Singleton

a will report now as being of the same class as singleton even if it does not look like it. So singletons using complicated classes end up depending on we don't mess much with them.

Being so, we can have the same effect and use simpler things like a variable or a module. Still, if we want use classes for clarity and because in Python a class is an object, so we already have the object (not and instance, but it will do just like).

class Singleton:
    def __new__(cls): raise AssertionError # Singletons can't have instances

There we have a nice assertion error if we try to create an instance, and we can store on derivations static members and make changes to them at runtime (I love Python). This object is as good as other about half brothers (you still can create them if you wish), however it will tend to run faster due to simplicity.

How do you debug React Native?

  1. Run your app in simulator - react-native run-ios
  2. Press ctrl + d and click on Debug JS Remotely

enter image description here

  1. webpage should open up at http://localhost:8081/debugger-ui , if not type the URL and go to this link in Chrome
  2. Right click on the page and click Inspect and it should open the developer tools for chrome

enter image description here

  1. Go to the sources in the top menu and find your js class file in the right hand side file explorer

  2. You can put breakpoints to the view and debug the code in there as you can see in the image.

Stop Chrome Caching My JS Files

I was getting the same css file when I browse website(on hosting company server with real domain) and I was unable to get the updated version on chrome. I was able to get the updated version of the file when I browse it on Firefox. None of these answers worked for me. I also have the website files on my machine and browse the site with localhost using my local apache server. I shut down my apache server and I was able to get the updated file. Somehow my local apache server was messing with the chrome cache. Hope this helps someone as it was very hard for me to fix this.

How to extract epoch from LocalDate and LocalDateTime?

'Millis since unix epoch' represents an instant, so you should use the Instant class:

private long toEpochMilli(LocalDateTime localDateTime)
{
  return localDateTime.atZone(ZoneId.systemDefault())
    .toInstant().toEpochMilli();
}

How to add a title to a html select tag

With a default option having selected attribute

<select>
        <option value="" selected>Choose your city</option>
        <option value ="sydney">Sydney</option>
        <option value ="melbourne">Melbourne</option>
        <option value ="cromwell">Cromwell</option>
        <option value ="queenstown">Queenstown</option>
</select>

Assign an initial value to radio button as checked

If you are using react-redux for your application and if you want to show data which is in the redux store, you can set "checked" option as below.

<label>Male</label>

 <input
   type="radio"
   name="gender"
   defaultChecked={this.props.gender == "0"}
 />



 <label>Female</label>
 <input
   type="radio"
   name="gender"
   defaultChecked={this.props.gender == "1"}
 />

pow (x,y) in Java

Additionally for what was said, if you want integer powers of two, then 1 << x (or 1L << x) is a faster way to calculate 2x than Math.pow(2,x) or a multiplication loop, and is guaranteed to give you an int (or long) result.

It only uses the lowest 5 (or 6) bits of x (i.e. x & 31 (or x & 63)), though, shifting between 0 and 31 (or 63) bits.

Styling Google Maps InfoWindow

Google wrote some code to assist with this. Here are some examples: Example using InfoBubble, Styled markers and Info Window Custom (using OverlayView).

The code in the links above take different routes to achieve similar results. The gist of it is that it is not easy to style InfoWindows directly, and it might be easier to use the additional InfoBubble class instead of InfoWindow, or to override GOverlay. Another option would be to modify the elements of the InfoWindow using javascript (or jQuery), like later ATOzTOA suggested.

Possibly the simplest of these examples is using InfoBubble instead of InfoWindow. InfoBubble is available by importing this file (which you should host yourself): http://google-maps-utility-library-v3.googlecode.com/svn/trunk/infobubble/src/infobubble.js

InfoBubble's Github project page.

InfoBubble is very stylable, compared to InfoWindow:

 infoBubble = new InfoBubble({
      map: map,
      content: '<div class="mylabel">The label</div>',
      position: new google.maps.LatLng(-32.0, 149.0),
      shadowStyle: 1,
      padding: 0,
      backgroundColor: 'rgb(57,57,57)',
      borderRadius: 5,
      arrowSize: 10,
      borderWidth: 1,
      borderColor: '#2c2c2c',
      disableAutoPan: true,
      hideCloseButton: true,
      arrowPosition: 30,
      backgroundClassName: 'transparent',
      arrowStyle: 2
});

infoBubble.open();

You can also call it with a given map and marker to open on:

infoBubble.open(map, marker);

As another example, the Info Window Custom example extends the GOverlay class from the Google Maps API and uses this as a base for creating a more flexible info window. It first creates the class:

/* An InfoBox is like an info window, but it displays
 * under the marker, opens quicker, and has flexible styling.
 * @param {GLatLng} latlng Point to place bar at
 * @param {Map} map The map on which to display this InfoBox.
 * @param {Object} opts Passes configuration options - content,
 *   offsetVertical, offsetHorizontal, className, height, width
 */
function InfoBox(opts) {
  google.maps.OverlayView.call(this);
  this.latlng_ = opts.latlng;
  this.map_ = opts.map;
  this.offsetVertical_ = -195;
  this.offsetHorizontal_ = 0;
  this.height_ = 165;
  this.width_ = 266;

  var me = this;
  this.boundsChangedListener_ =
    google.maps.event.addListener(this.map_, "bounds_changed", function() {
      return me.panMap.apply(me);
    });

  // Once the properties of this OverlayView are initialized, set its map so
  // that we can display it.  This will trigger calls to panes_changed and
  // draw.
  this.setMap(this.map_);
}

after which it proceeds to override GOverlay:

InfoBox.prototype = new google.maps.OverlayView();

You should then override the methods you need: createElement, draw, remove and panMap. It gets rather involved, but in theory you are just drawing a div on the map yourself now, instead of using a normal Info Window.