Programs & Examples On #Autoproxy

Is there any way of configuring Eclipse IDE proxy settings via an autoproxy configuration script?

In the file: $your_eclipse_installation\configuration.settings\org.eclipse.core.net.prefs

you need the option: systemProxiesEnabled=true

You can set it also by the Eclipse GUI: Go to Window -> Preferences -> General -> Network Connections Change the provider to "Native"

The first way is working even if your Eclipse is broken due to wrong configuration attempts.

Convert a RGB Color Value to a Hexadecimal String

Random ra = new Random();
int r, g, b;
r=ra.nextInt(255);
g=ra.nextInt(255);
b=ra.nextInt(255);
Color color = new Color(r,g,b);
String hex = Integer.toHexString(color.getRGB() & 0xffffff);
if (hex.length() < 6) {
    hex = "0" + hex;
}
hex = "#" + hex;

Time calculation in php (add 10 hours)?

Full code that shows now and 10 minutes added.....

$nowtime = date("Y-m-d H:i:s");
echo $nowtime;
$date = date('Y-m-d H:i:s', strtotime($nowtime . ' + 10 minute'));
echo "<br>".$date;

Best way to format if statement with multiple conditions

The first one is easier, because, if you read it left to right you get: "If something AND somethingelse AND somethingelse THEN" , which is an easy to understand sentence. The second example reads "If something THEN if somethingelse THEN if something else THEN", which is clumsy.

Also, consider if you wanted to use some ORs in your clause - how would you do that in the second style?

How do I add FTP support to Eclipse?

As none of the other solutions mentioned satisfied me, I wrote a script that uses WinSCP to sync local directories in a project to a FTP(S)/SFTP/SCP Server when eclipse's autobuild feature is triggered. Obviously, this is a Windows-only solution.

Maybe someone finds this useful: http://rays-blog.de/2012/05/05/94/use-winscp-to-upload-files-using-eclipses-autobuild-feature/

IF EXISTS condition not working with PLSQL

IF EXISTS() is semantically incorrect. EXISTS condition can be used only inside a SQL statement. So you might rewrite your pl/sql block as follows:

declare
  l_exst number(1);
begin
  select case 
           when exists(select ce.s_regno 
                         from courseoffering co
                         join co_enrolment ce
                           on ce.co_id = co.co_id
                        where ce.s_regno=403 
                          and ce.coe_completionstatus = 'C' 
                          and ce.c_id = 803
                          and rownum = 1
                        )
           then 1
           else 0
         end  into l_exst
  from dual;

  if l_exst = 1 
  then
    DBMS_OUTPUT.put_line('YES YOU CAN');
  else
    DBMS_OUTPUT.put_line('YOU CANNOT'); 
  end if;
end;

Or you can simply use count function do determine the number of rows returned by the query, and rownum=1 predicate - you only need to know if a record exists:

declare
  l_exst number;
begin
   select count(*) 
     into l_exst
     from courseoffering co
          join co_enrolment ce
            on ce.co_id = co.co_id
    where ce.s_regno=403 
      and ce.coe_completionstatus = 'C' 
      and ce.c_id = 803
      and rownum = 1;

  if l_exst = 0
  then
    DBMS_OUTPUT.put_line('YOU CANNOT');
  else
    DBMS_OUTPUT.put_line('YES YOU CAN');
  end if;
end;

Select a Column in SQL not in Group By

The columns in the result set of a select query with group by clause must be:

  • an expression used as one of the group by criteria , or ...
  • an aggregate function , or ...
  • a literal value

So, you can't do what you want to do in a single, simple query. The first thing to do is state your problem statement in a clear way, something like:

I want to find the individual claim row bearing the most recent creation date within each group in my claims table

Given

create table dbo.some_claims_table
(
  claim_id     int      not null ,
  group_id     int      not null ,
  date_created datetime not null ,

  constraint some_table_PK primary key ( claim_id                ) ,
  constraint some_table_AK01 unique    ( group_id , claim_id     ) ,
  constraint some_Table_AK02 unique    ( group_id , date_created ) ,

)

The first thing to do is identify the most recent creation date for each group:

select group_id ,
       date_created = max( date_created )
from dbo.claims_table
group by group_id

That gives you the selection criteria you need (1 row per group, with 2 columns: group_id and the highwater created date) to fullfill the 1st part of the requirement (selecting the individual row from each group. That needs to be a virtual table in your final select query:

select *
from dbo.claims_table t
join ( select group_id ,
       date_created = max( date_created )
       from dbo.claims_table
       group by group_id
      ) x on x.group_id     = t.group_id
         and x.date_created = t.date_created

If the table is not unique by date_created within group_id (AK02), you you can get duplicate rows for a given group.

How to get text box value in JavaScript

If it is in a form then it would be:

<form name="jojo">
<input name="jobtitle">
</form>

Then you would say in javascript:

var val= document.jojo.jobtitle.value

document.formname.elementname

What's the better (cleaner) way to ignore output in PowerShell?

I realize this is an old thread, but for those taking @JasonMArcher's accepted answer above as fact, I'm surprised it has not been corrected many of us have known for years it is actually the PIPELINE adding the delay and NOTHING to do with whether it is Out-Null or not. In fact, if you run the tests below you will quickly see that the same "faster" casting to [void] and $void= that for years we all used thinking it was faster, are actually JUST AS SLOW and in fact VERY SLOW when you add ANY pipelining whatsoever. In other words, as soon as you pipe to anything, the whole rule of not using out-null goes into the trash.

Proof, the last 3 tests in the list below. The horrible Out-null was 32339.3792 milliseconds, but wait - how much faster was casting to [void]? 34121.9251 ms?!? WTF? These are REAL #s on my system, casting to VOID was actually SLOWER. How about =$null? 34217.685ms.....still friggin SLOWER! So, as the last three simple tests show, the Out-Null is actually FASTER in many cases when the pipeline is already in use.

So, why is this? Simple. It is and always was 100% a hallucination that piping to Out-Null was slower. It is however that PIPING TO ANYTHING is slower, and didn't we kind of already know that through basic logic? We just may not have know HOW MUCH slower, but these tests sure tell a story about the cost of using the pipeline if you can avoid it. And, we were not really 100% wrong because there is a very SMALL number of true scenarios where out-null is evil. When? When adding Out-Null is adding the ONLY pipeline activity. In other words....the reason a simple command like $(1..1000) | Out-Null as shown above showed true.

If you simply add an additional pipe to Out-String to every test above, the #s change radically (or just paste the ones below) and as you can see for yourself, the Out-Null actually becomes FASTER in many cases:

$GetProcess = Get-Process

# Batch 1 - Test 1 
(Measure-Command { 
for ($i = 1; $i -lt 99; $i++) 
{ 
$GetProcess | Out-Null 
} 
}).TotalMilliseconds

# Batch 1 - Test 2 
(Measure-Command { 
for ($i = 1; $i -lt 99; $i++) 
{ 
[void]($GetProcess) 
} 
}).TotalMilliseconds

# Batch 1 - Test 3 
(Measure-Command { 
for ($i = 1; $i -lt 99; $i++) 
{ 
$null = $GetProcess 
} 
}).TotalMilliseconds

# Batch 2 - Test 1 
(Measure-Command { 
for ($i = 1; $i -lt 99; $i++) 
{ 
$GetProcess | Select-Object -Property ProcessName | Out-Null 
} 
}).TotalMilliseconds

# Batch 2 - Test 2 
(Measure-Command { 
for ($i = 1; $i -lt 99; $i++) 
{ 
[void]($GetProcess | Select-Object -Property ProcessName ) 
} 
}).TotalMilliseconds

# Batch 2 - Test 3 
(Measure-Command { 
for ($i = 1; $i -lt 99; $i++) 
{ 
$null = $GetProcess | Select-Object -Property ProcessName 
} 
}).TotalMilliseconds

# Batch 3 - Test 1 
(Measure-Command { 
for ($i = 1; $i -lt 99; $i++) 
{ 
$GetProcess | Select-Object -Property Handles, NPM, PM, WS, VM, CPU, Id, SI, Name | Out-Null 
} 
}).TotalMilliseconds

# Batch 3 - Test 2 
(Measure-Command { 
for ($i = 1; $i -lt 99; $i++) 
{ 
[void]($GetProcess | Select-Object -Property Handles, NPM, PM, WS, VM, CPU, Id, SI, Name ) 
} 
}).TotalMilliseconds

# Batch 3 - Test 3 
(Measure-Command { 
for ($i = 1; $i -lt 99; $i++) 
{ 
$null = $GetProcess | Select-Object -Property Handles, NPM, PM, WS, VM, CPU, Id, SI, Name 
} 
}).TotalMilliseconds

# Batch 4 - Test 1 
(Measure-Command { 
for ($i = 1; $i -lt 99; $i++) 
{ 
$GetProcess | Out-String | Out-Null 
} 
}).TotalMilliseconds

# Batch 4 - Test 2 
(Measure-Command { 
for ($i = 1; $i -lt 99; $i++) 
{ 
[void]($GetProcess | Out-String ) 
} 
}).TotalMilliseconds

# Batch 4 - Test 3 
(Measure-Command { 
for ($i = 1; $i -lt 99; $i++) 
{ 
$null = $GetProcess | Out-String 
} 
}).TotalMilliseconds

jQuery checkbox checked state changed event

If your intention is to attach event only on checked checkboxes (so it would fire when they are unchecked and checked later again) then this is what you want.

$(function() {
    $("input[type='checkbox']:checked").change(function() {

    })
})

if your intention is to attach event to all checkboxes (checked and unchecked)

$(function() {
    $("input[type='checkbox']").change(function() {

    })
})

if you want it to fire only when they are being checked (from unchecked) then @James Allardice answer above.

BTW input[type='checkbox']:checked is CSS selector.

Button background as transparent

Add this in your Xml - android:background="@android:color/transparent"

        <Button
            android:id="@+id/button1"
            android:layout_width="match_parent"
            android:layout_height="match_parent"
            android:text="Button"
            android:background="@android:color/transparent"
            android:textStyle="bold"/>

A warning - comparison between signed and unsigned integer expressions

The primary issue is that underlying hardware, the CPU, only has instructions to compare two signed values or compare two unsigned values. If you pass the unsigned comparison instruction a signed, negative value, it will treat it as a large positive number. So, -1, the bit pattern with all bits on (twos complement), becomes the maximum unsigned value for the same number of bits.

8-bits: -1 signed is the same bits as 255 unsigned 16-bits: -1 signed is the same bits as 65535 unsigned etc.

So, if you have the following code:

int fd;
fd = open( .... );

int cnt;
SomeType buf;

cnt = read( fd, &buf, sizeof(buf) );

if( cnt < sizeof(buf) ) {
    perror("read error");
}

you will find that if the read(2) call fails due to the file descriptor becoming invalid (or some other error), that cnt will be set to -1. When comparing to sizeof(buf), an unsigned value, the if() statement will be false because 0xffffffff is not less than sizeof() some (reasonable, not concocted to be max size) data structure.

Thus, you have to write the above if, to remove the signed/unsigned warning as:

if( cnt < 0 || (size_t)cnt < sizeof(buf) ) {
    perror("read error");
}

This just speaks loudly to the problems.

1.  Introduction of size_t and other datatypes was crafted to mostly work, 
    not engineered, with language changes, to be explicitly robust and 
    fool proof.
2.  Overall, C/C++ data types should just be signed, as Java correctly
    implemented.

If you have values so large that you can't find a signed value type that works, you are using too small of a processor or too large of a magnitude of values in your language of choice. If, like with money, every digit counts, there are systems to use in most languages which provide you infinite digits of precision. C/C++ just doesn't do this well, and you have to be very explicit about everything around types as mentioned in many of the other answers here.

How do I detach objects in Entity Framework Code First?

This is an option:

dbContext.Entry(entity).State = EntityState.Detached;

Android: remove notification from notification bar

Please try this,

public void removeNotification(Context context, int notificationId) {      
    NotificationManager nMgr = (NotificationManager) context.getApplicationContext()
            .getSystemService(Context.NOTIFICATION_SERVICE);
    nMgr.cancel(notificationId);
}

How can I tell if a DOM element is visible in the current viewport?

Update: Time marches on and so have our browsers. This technique is no longer recommended and you should use Dan's solution if you do not need to support version of Internet Explorer before 7.

Original solution (now outdated):

This will check if the element is entirely visible in the current viewport:

function elementInViewport(el) {
  var top = el.offsetTop;
  var left = el.offsetLeft;
  var width = el.offsetWidth;
  var height = el.offsetHeight;

  while(el.offsetParent) {
    el = el.offsetParent;
    top += el.offsetTop;
    left += el.offsetLeft;
  }

  return (
    top >= window.pageYOffset &&
    left >= window.pageXOffset &&
    (top + height) <= (window.pageYOffset + window.innerHeight) &&
    (left + width) <= (window.pageXOffset + window.innerWidth)
  );
}

You could modify this simply to determine if any part of the element is visible in the viewport:

function elementInViewport2(el) {
  var top = el.offsetTop;
  var left = el.offsetLeft;
  var width = el.offsetWidth;
  var height = el.offsetHeight;

  while(el.offsetParent) {
    el = el.offsetParent;
    top += el.offsetTop;
    left += el.offsetLeft;
  }

  return (
    top < (window.pageYOffset + window.innerHeight) &&
    left < (window.pageXOffset + window.innerWidth) &&
    (top + height) > window.pageYOffset &&
    (left + width) > window.pageXOffset
  );
}

Use Async/Await with Axios in React.js

Two issues jump out:

  1. Your getData never returns anything, so its promise (async functions always return a promise) will resolve with undefined when it resolves

  2. The error message clearly shows you're trying to directly render the promise getData returns, rather than waiting for it to resolve and then rendering the resolution

Addressing #1: getData should return the result of calling json:

async getData(){
   const res = await axios('/data');
   return await res.json();
}

Addressig #2: We'd have to see more of your code, but fundamentally, you can't do

<SomeElement>{getData()}</SomeElement>

...because that doesn't wait for the resolution. You'd need instead to use getData to set state:

this.getData().then(data => this.setState({data}))
              .catch(err => { /*...handle the error...*/});

...and use that state when rendering:

<SomeElement>{this.state.data}</SomeElement>

Update: Now that you've shown us your code, you'd need to do something like this:

class App extends React.Component{
    async getData() {
        const res = await axios('/data');
        return await res.json(); // (Or whatever)
    }
    constructor(...args) {
        super(...args);
        this.state = {data: null};
    }
    componentDidMount() {
        if (!this.state.data) {
            this.getData().then(data => this.setState({data}))
                          .catch(err => { /*...handle the error...*/});
        }
    }
    render() {
        return (
            <div>
                {this.state.data ? <em>Loading...</em> : this.state.data}
            </div>
        );
    }
}

Futher update: You've indicated a preference for using await in componentDidMount rather than then and catch. You'd do that by nesting an async IIFE function within it and ensuring that function can't throw. (componentDidMount itself can't be async, nothing will consume that promise.) E.g.:

class App extends React.Component{
    async getData() {
        const res = await axios('/data');
        return await res.json(); // (Or whatever)
    }
    constructor(...args) {
        super(...args);
        this.state = {data: null};
    }
    componentDidMount() {
        if (!this.state.data) {
            (async () => {
                try {
                    this.setState({data: await this.getData()});
                } catch (e) {
                    //...handle the error...
                }
            })();
        }
    }
    render() {
        return (
            <div>
                {this.state.data ? <em>Loading...</em> : this.state.data}
            </div>
        );
    }
}

how to change text box value with jQuery?

This will change the value when button is clicked:

<script>
  jQuery(function() {
    $('#b11').click(function(e) {
      e.preventDefault();
      var name = "hello";
      $("#t1").val(name);
    });
  });
</script>

Javadoc link to method in other class

For the Javadoc tag @see, you don't need to use @link; Javadoc will create a link for you. Try

@see com.my.package.Class#method()

Here's more info about @see.

Postgres could not connect to server

This happens when postgres server is not running. Steps to properly install Postgres via Homebrew on MAC :

  1. brew install postgres

  2. initdb /Users/<username>/db -E utf8 [This initializes postgres to use the given directory as the database directory. Normally it is not adviced to use the user directory for database storage. Edit sudoers file to add initdb and similar commands and then run initdb on /usr/local/var/postgres]

  3. pg_ctl -D /Users/<username>/db -l logfile start [After getting success with step 2 it will prompt to run step 3. This command manually starts the server.]

What are some resources for getting started in operating system development?

Write a microcontroller OS. I recommend an x86 based microcontroller. A modern OS is just huge. Learn the basics first.

Reset identity seed after deleting records in SQL Server

Although most answers are suggesting RESEED to 0, many times we need to just reseed to next Id available

declare @max int
select @max=max([Id]) from [TestTable]
if @max IS NULL   --check when max is returned as null
  SET @max = 0
DBCC CHECKIDENT ('[TestTable]', RESEED, @max)

This will check the table and reset to the next ID.

Google maps Marker Label with multiple characters

As of API version 3.26.10, you can set the marker label with more than one characters. The restriction is lifted.

Try it, it works!

Moreover, using a MarkerLabel object instead of just a string, you can set a number of properties for the appearance, and if using a custom Icon you can set the labelOrigin property to reposition the label.

Source: https://code.google.com/p/gmaps-api-issues/issues/detail?id=8578#c30 (also, you can report any issues regarding this at the above linked thread)

Typescript: Type 'string | undefined' is not assignable to type 'string'

You could make use of Typescript's optional chaining. Example:

const name = person?.name;

If the property name exists on the person object you would get its value but if not it would automatically return undefined.

You could make use of this resource for a better understanding.

https://www.typescriptlang.org/docs/handbook/release-notes/typescript-3-7.html

How to find specific lines in a table using Selenium?

if you want to access table cell

WebElement thirdCell = driver.findElement(By.Xpath("//table/tbody/tr[2]/td[1]")); 

If you want to access nested table cell -

WebElement thirdCell = driver.findElement(By.Xpath("//table/tbody/tr[2]/td[2]"+//table/tbody/tr[1]/td[2]));

For more details visit this Tutorial

Reset auto increment counter in postgres

To set the sequence counter:

setval('product_id_seq', 1453);

If you don't know the sequence name use the pg_get_serial_sequence function:

select pg_get_serial_sequence('product', 'id');
 pg_get_serial_sequence 
------------------------
 public.product_id_seq

The parameters are the table name and the column name.

Or just issue a \d product at the psql prompt:

=> \d product
                         Table "public.product"
 Column |  Type   |                      Modifiers                       
--------+---------+------------------------------------------------------
 id     | integer | not null default nextval('product_id_seq'::regclass)
 name   | text    | 

How to check if a string contains a substring in Bash

My .bash_profile file and how I used grep:

If the PATH environment variable includes my two bin directories, don't append them,

# .bash_profile
# Get the aliases and functions
if [ -f ~/.bashrc ]; then
    . ~/.bashrc
fi

U=~/.local.bin:~/bin

if ! echo "$PATH" | grep -q "home"; then
    export PATH=$PATH:${U}
fi

C# static class constructor

We can create static constructor

static class StaticParent 
{
  StaticParent() 
  {
    //write your initialization code here

  }

}

and it is always parameter less.

static class StaticParent
{
    static int i =5;
    static StaticParent(int i)  //Gives error
    {
      //write your initialization code here
    }
}

and it doesn't have the access modifier

Add & delete view from Layout

For changing visibility:

predictbtn.setVisibility(View.INVISIBLE);

For removing:

predictbtn.setVisibility(View.GONE);

JUnit assertEquals(double expected, double actual, double epsilon)

Epsilon is your "fuzz factor," since doubles may not be exactly equal. Epsilon lets you describe how close they have to be.

If you were expecting 3.14159 but would take anywhere from 3.14059 to 3.14259 (that is, within 0.001), then you should write something like

double myPi = 22.0d / 7.0d; //Don't use this in real life!
assertEquals(3.14159, myPi, 0.001);

(By the way, 22/7 comes out to 3.1428+, and would fail the assertion. This is a good thing.)

How can I handle the warning of file_get_contents() function in PHP?

You could use this script

$url = @file_get_contents("http://www.itreb.info");
if ($url) {
    // if url is true execute this 
    echo $url;
} else {
    // if not exceute this 
    echo "connection error";
}

Remove certain characters from a string

UPDATE yourtable 
SET field_or_column =REPLACE ('current string','findpattern', 'replacepattern') 
WHERE 1

Auto Increment after delete in MySQL

you can select the ids like so:

set @rank = 0;
select id, @rank:=@rank+1 from tbl order by id

the result is a list of ids, and their positions in the sequence.

you can also reset the ids like so:

set @rank = 0;
update tbl a join (select id, @rank:=@rank+1 as rank from tbl order by id) b
  on a.id = b.id set a.id = b.rank;

you could also just print out the first unused id like so:

select min(id) as next_id from ((select a.id from (select 1 as id) a
  left join tbl b on a.id = b.id where b.id is null) union
  (select min(a.id) + 1 as id from tbl a left join tbl b on a.id+1 = b.id
  where b.id is null)) c;

after each insert, you can reset the auto_increment:

alter table tbl auto_increment = 16

or explicitly set the id value when doing the insert:

insert into tbl values (16, 'something');

typically this isn't necessary, you have count(*) and the ability to create a ranking number in your result sets. a typical ranking might be:

set @rank = 0;
select a.name, a.amount, b.rank from cust a,
  (select amount, @rank:=@rank+1 as rank from cust order by amount desc) b
  where a.amount = b.amount

customers ranked by amount spent.

How do I get bit-by-bit data from an integer value in C?

As requested, I decided to extend my comment on forefinger's answer to a full-fledged answer. Although his answer is correct, it is needlessly complex. Furthermore all current answers use signed ints to represent the values. This is dangerous, as right-shifting of negative values is implementation-defined (i.e. not portable) and left-shifting can lead to undefined behavior (see this question).

By right-shifting the desired bit into the least significant bit position, masking can be done with 1. No need to compute a new mask value for each bit.

(n >> k) & 1

As a complete program, computing (and subsequently printing) an array of single bit values:

#include <stdio.h>
#include <stdlib.h>

int main(int argc, char** argv)
{
    unsigned
        input = 0b0111u,
        n_bits = 4u,
        *bits = (unsigned*)malloc(sizeof(unsigned) * n_bits),
        bit = 0;

    for(bit = 0; bit < n_bits; ++bit)
        bits[bit] = (input >> bit) & 1;

    for(bit = n_bits; bit--;)
        printf("%u", bits[bit]);
    printf("\n");

    free(bits);
}

Assuming that you want to calculate all bits as in this case, and not a specific one, the loop can be further changed to

for(bit = 0; bit < n_bits; ++bit, input >>= 1)
    bits[bit] = input & 1;

This modifies input in place and thereby allows the use of a constant width, single-bit shift, which may be more efficient on some architectures.

Android getActivity() is undefined

If you want to call your activity, just use this . You use the getActivity method when you are inside a fragment.

Where is `%p` useful with printf?

When you need to debug, use printf with %p option is really helpful. You see 0x0 when you have a NULL value.

PowerShell script to return versions of .NET Framework on a machine?

Here's the general idea:

Get child items in the .NET Framework directory that are containers whose names match the pattern v number dot number. Sort them by descending name, take the first object, and return its name property.

Here's the script:

(Get-ChildItem -Path $Env:windir\Microsoft.NET\Framework | Where-Object {$_.PSIsContainer -eq $true } | Where-Object {$_.Name -match 'v\d\.\d'} | Sort-Object -Property Name -Descending | Select-Object -First 1).Name

Hide/Show Column in an HTML Table

Here's a little more fully featured answer that provides some user interaction on a per column basis. If this is going to be a dynamic experience, there needs to be a clickable toggle on each column that indicates the ability to hide the column, and then a way to restore previously hidden columns.

That would look something like this in JavaScript:

$('.hide-column').click(function(e){
  var $btn = $(this);
  var $cell = $btn.closest('th,td')
  var $table = $btn.closest('table')

  // get cell location - https://stackoverflow.com/a/4999018/1366033
  var cellIndex = $cell[0].cellIndex + 1;

  $table.find(".show-column-footer").show()
  $table.find("tbody tr, thead tr")
        .children(":nth-child("+cellIndex+")")
        .hide()
})

$(".show-column-footer").click(function(e) {
    var $table = $(this).closest('table')
    $table.find(".show-column-footer").hide()
    $table.find("th, td").show()

})

To support this, we'll add some markup to the table. In each column header, we can add something like this to provide a visual indicator of something clickable

<button class="pull-right btn btn-default btn-condensed hide-column" 
            data-toggle="tooltip" data-placement="bottom" title="Hide Column">
    <i class="fa fa-eye-slash"></i>  
</button>

We'll allow the user to restore columns via a link in the table footer. If it's not persistent by default, then toggling it on dynamically in the header could jostle around the table, but you can really put it anywhere you'd like:

<tfoot class="show-column-footer">
   <tr>
    <th colspan="4"><a class="show-column" href="#">Some columns hidden - click to show all</a></th>
  </tr>
</tfoot>

That's the basic functionality. Here's a demo below with a couple more things fleshed out. You can also add a tooltip to the button to help clarify its purpose, style the button a little more organically to a table header, and collapse the column width in order to add some (somewhat wonky) css animations to make the transition a little less jumpy.

Demo Screengrab

Working Demo in jsFiddle & Stack Snippets:

_x000D_
_x000D_
$(function() {_x000D_
  // on init_x000D_
  $(".table-hideable .hide-col").each(HideColumnIndex);_x000D_
_x000D_
  // on click_x000D_
  $('.hide-column').click(HideColumnIndex)_x000D_
_x000D_
  function HideColumnIndex() {_x000D_
    var $el = $(this);_x000D_
    var $cell = $el.closest('th,td')_x000D_
    var $table = $cell.closest('table')_x000D_
_x000D_
    // get cell location - https://stackoverflow.com/a/4999018/1366033_x000D_
    var colIndex = $cell[0].cellIndex + 1;_x000D_
_x000D_
    // find and hide col index_x000D_
    $table.find("tbody tr, thead tr")_x000D_
      .children(":nth-child(" + colIndex + ")")_x000D_
      .addClass('hide-col');_x000D_
      _x000D_
    // show restore footer_x000D_
    $table.find(".footer-restore-columns").show()_x000D_
  }_x000D_
_x000D_
  // restore columns footer_x000D_
  $(".restore-columns").click(function(e) {_x000D_
    var $table = $(this).closest('table')_x000D_
    $table.find(".footer-restore-columns").hide()_x000D_
    $table.find("th, td")_x000D_
      .removeClass('hide-col');_x000D_
_x000D_
  })_x000D_
_x000D_
  $('[data-toggle="tooltip"]').tooltip({_x000D_
    trigger: 'hover'_x000D_
  })_x000D_
_x000D_
})
_x000D_
body {_x000D_
  padding: 15px;_x000D_
}_x000D_
_x000D_
.table-hideable td,_x000D_
.table-hideable th {_x000D_
  width: auto;_x000D_
  transition: width .5s, margin .5s;_x000D_
}_x000D_
_x000D_
.btn-condensed.btn-condensed {_x000D_
  padding: 0 5px;_x000D_
  box-shadow: none;_x000D_
}_x000D_
_x000D_
_x000D_
/* use class to have a little animation */_x000D_
.hide-col {_x000D_
  width: 0px !important;_x000D_
  height: 0px !important;_x000D_
  display: block !important;_x000D_
  overflow: hidden !important;_x000D_
  margin: 0 !important;_x000D_
  padding: 0 !important;_x000D_
  border: none !important;_x000D_
}
_x000D_
<link rel="stylesheet" type="text/css" href="https://cdnjs.cloudflare.com/ajax/libs/twitter-bootstrap/3.3.7/css/bootstrap.css">_x000D_
<link rel="stylesheet" type="text/css" href="https://cdnjs.cloudflare.com/ajax/libs/bootswatch/3.3.7/paper/bootstrap.min.css">_x000D_
<link rel="stylesheet" type="text/css" href="https://cdnjs.cloudflare.com/ajax/libs/font-awesome/4.7.0/css/font-awesome.css">_x000D_
<script type="text/javascript" src="https://cdnjs.cloudflare.com/ajax/libs/jquery/3.2.1/jquery.min.js"></script>_x000D_
<script type="text/javascript" src="https://cdnjs.cloudflare.com/ajax/libs/twitter-bootstrap/3.3.7/js/bootstrap.min.js"></script>_x000D_
_x000D_
_x000D_
_x000D_
_x000D_
<table class="table table-condensed table-hover table-bordered table-striped table-hideable">_x000D_
_x000D_
  <thead>_x000D_
    <tr>_x000D_
      <th>_x000D_
        Controller_x000D_
        <button class="pull-right btn btn-default btn-condensed hide-column" data-toggle="tooltip" data-placement="bottom" title="Hide Column">_x000D_
          <i class="fa fa-eye-slash"></i>  _x000D_
        </button>_x000D_
      </th>_x000D_
      <th class="hide-col">_x000D_
        Action_x000D_
        <button class="pull-right btn btn-default btn-condensed hide-column" data-toggle="tooltip" data-placement="bottom" title="Hide Column">_x000D_
          <i class="fa fa-eye-slash"></i>  _x000D_
        </button>_x000D_
      </th>_x000D_
      <th>_x000D_
        Type_x000D_
        <button class="pull-right btn btn-default btn-condensed hide-column" data-toggle="tooltip" data-placement="bottom" title="Hide Column">_x000D_
          <i class="fa fa-eye-slash"></i>  _x000D_
        </button>_x000D_
      </th>_x000D_
      <th>_x000D_
        Attributes_x000D_
        <button class="pull-right btn btn-default btn-condensed hide-column" data-toggle="tooltip" data-placement="bottom" title="Hide Column">_x000D_
          <i class="fa fa-eye-slash"></i>  _x000D_
        </button>_x000D_
      </th>_x000D_
  </thead>_x000D_
  <tbody>_x000D_
_x000D_
    <tr>_x000D_
      <td>Home</td>_x000D_
      <td>Index</td>_x000D_
      <td>ActionResult</td>_x000D_
      <td>Authorize</td>_x000D_
    </tr>_x000D_
_x000D_
    <tr>_x000D_
      <td>Client</td>_x000D_
      <td>Index</td>_x000D_
      <td>ActionResult</td>_x000D_
      <td>Authorize</td>_x000D_
    </tr>_x000D_
_x000D_
    <tr>_x000D_
      <td>Client</td>_x000D_
      <td>Edit</td>_x000D_
      <td>ActionResult</td>_x000D_
      <td>Authorize</td>_x000D_
    </tr>_x000D_
_x000D_
  </tbody>_x000D_
  <tfoot class="footer-restore-columns">_x000D_
    <tr>_x000D_
      <th colspan="4"><a class="restore-columns" href="#">Some columns hidden - click to show all</a></th>_x000D_
    </tr>_x000D_
  </tfoot>_x000D_
</table>
_x000D_
_x000D_
_x000D_

Reading From A Text File - Batch

Your code "for /f "tokens=* delims=" %%x in (a.txt) do echo %%x" will work on most Windows Operating Systems unless you have modified commands.

So you could instead "cd" into the directory to read from before executing the "for /f" command to follow out the string. For instance if the file "a.txt" is located at C:\documents and settings\%USERNAME%\desktop\a.txt then you'd use the following.

cd "C:\documents and settings\%USERNAME%\desktop"
for /f "tokens=* delims=" %%x in (a.txt) do echo %%x
echo.
echo.
echo.
pause >nul
exit

But since this doesn't work on your computer for x reason there is an easier and more efficient way of doing this. Using the "type" command.

@echo off
color a
cls
cd "C:\documents and settings\%USERNAME%\desktop"
type a.txt
echo.
echo.
pause >nul
exit

Or if you'd like them to select the file from which to write in the batch you could do the following.

@echo off
:A
color a
cls
echo Choose the file that you want to read.
echo.
echo.
tree
echo.
echo.
echo.
set file=
set /p file=File:
cls
echo Reading from %file%
echo.
type %file%
echo.
echo.
echo.
set re=
set /p re=Y/N?:
if %re%==Y goto :A
if %re%==y goto :A
exit

Python progression path - From apprentice to guru

Understand Introspection

  • write a dir() equivalent
  • write a type() equivalent
  • figure out how to "monkey-patch"
  • use the dis module to see how various language constructs work

Doing these things will

  • give you some good theoretical knowledge about how python is implemented
  • give you some good practical experience in lower-level programming
  • give you a good intuitive feel for python data structures

C++ equivalent of java's instanceof

Instanceof implementation without dynamic_cast

I think this question is still relevant today. Using the C++11 standard you are now able to implement a instanceof function without using dynamic_cast like this:

if (dynamic_cast<B*>(aPtr) != nullptr) {
  // aPtr is instance of B
} else {
  // aPtr is NOT instance of B
}

But you're still reliant on RTTI support. So here is my solution for this problem depending on some Macros and Metaprogramming Magic. The only drawback imho is that this approach does not work for multiple inheritance.

InstanceOfMacros.h

#include <set>
#include <tuple>
#include <typeindex>

#define _EMPTY_BASE_TYPE_DECL() using BaseTypes = std::tuple<>;
#define _BASE_TYPE_DECL(Class, BaseClass) \
  using BaseTypes = decltype(std::tuple_cat(std::tuple<BaseClass>(), Class::BaseTypes()));
#define _INSTANCE_OF_DECL_BODY(Class)                                 \
  static const std::set<std::type_index> baseTypeContainer;           \
  virtual bool instanceOfHelper(const std::type_index &_tidx) {       \
    if (std::type_index(typeid(ThisType)) == _tidx) return true;      \
    if (std::tuple_size<BaseTypes>::value == 0) return false;         \
    return baseTypeContainer.find(_tidx) != baseTypeContainer.end();  \
  }                                                                   \
  template <typename... T>                                            \
  static std::set<std::type_index> getTypeIndexes(std::tuple<T...>) { \
    return std::set<std::type_index>{std::type_index(typeid(T))...};  \
  }

#define INSTANCE_OF_SUB_DECL(Class, BaseClass) \
 protected:                                    \
  using ThisType = Class;                      \
  _BASE_TYPE_DECL(Class, BaseClass)            \
  _INSTANCE_OF_DECL_BODY(Class)

#define INSTANCE_OF_BASE_DECL(Class)                                                    \
 protected:                                                                             \
  using ThisType = Class;                                                               \
  _EMPTY_BASE_TYPE_DECL()                                                               \
  _INSTANCE_OF_DECL_BODY(Class)                                                         \
 public:                                                                                \
  template <typename Of>                                                                \
  typename std::enable_if<std::is_base_of<Class, Of>::value, bool>::type instanceOf() { \
    return instanceOfHelper(std::type_index(typeid(Of)));                               \
  }

#define INSTANCE_OF_IMPL(Class) \
  const std::set<std::type_index> Class::baseTypeContainer = Class::getTypeIndexes(Class::BaseTypes());

Demo

You can then use this stuff (with caution) as follows:

DemoClassHierarchy.hpp*

#include "InstanceOfMacros.h"

struct A {
  virtual ~A() {}
  INSTANCE_OF_BASE_DECL(A)
};
INSTANCE_OF_IMPL(A)

struct B : public A {
  virtual ~B() {}
  INSTANCE_OF_SUB_DECL(B, A)
};
INSTANCE_OF_IMPL(B)

struct C : public A {
  virtual ~C() {}
  INSTANCE_OF_SUB_DECL(C, A)
};
INSTANCE_OF_IMPL(C)

struct D : public C {
  virtual ~D() {}
  INSTANCE_OF_SUB_DECL(D, C)
};
INSTANCE_OF_IMPL(D)

The following code presents a small demo to verify rudimentary the correct behavior.

InstanceOfDemo.cpp

#include <iostream>
#include <memory>
#include "DemoClassHierarchy.hpp"

int main() {
  A *a2aPtr = new A;
  A *a2bPtr = new B;
  std::shared_ptr<A> a2cPtr(new C);
  C *c2dPtr = new D;
  std::unique_ptr<A> a2dPtr(new D);

  std::cout << "a2aPtr->instanceOf<A>(): expected=1, value=" << a2aPtr->instanceOf<A>() << std::endl;
  std::cout << "a2aPtr->instanceOf<B>(): expected=0, value=" << a2aPtr->instanceOf<B>() << std::endl;
  std::cout << "a2aPtr->instanceOf<C>(): expected=0, value=" << a2aPtr->instanceOf<C>() << std::endl;
  std::cout << "a2aPtr->instanceOf<D>(): expected=0, value=" << a2aPtr->instanceOf<D>() << std::endl;
  std::cout << std::endl;
  std::cout << "a2bPtr->instanceOf<A>(): expected=1, value=" << a2bPtr->instanceOf<A>() << std::endl;
  std::cout << "a2bPtr->instanceOf<B>(): expected=1, value=" << a2bPtr->instanceOf<B>() << std::endl;
  std::cout << "a2bPtr->instanceOf<C>(): expected=0, value=" << a2bPtr->instanceOf<C>() << std::endl;
  std::cout << "a2bPtr->instanceOf<D>(): expected=0, value=" << a2bPtr->instanceOf<D>() << std::endl;
  std::cout << std::endl;
  std::cout << "a2cPtr->instanceOf<A>(): expected=1, value=" << a2cPtr->instanceOf<A>() << std::endl;
  std::cout << "a2cPtr->instanceOf<B>(): expected=0, value=" << a2cPtr->instanceOf<B>() << std::endl;
  std::cout << "a2cPtr->instanceOf<C>(): expected=1, value=" << a2cPtr->instanceOf<C>() << std::endl;
  std::cout << "a2cPtr->instanceOf<D>(): expected=0, value=" << a2cPtr->instanceOf<D>() << std::endl;
  std::cout << std::endl;
  std::cout << "c2dPtr->instanceOf<A>(): expected=1, value=" << c2dPtr->instanceOf<A>() << std::endl;
  std::cout << "c2dPtr->instanceOf<B>(): expected=0, value=" << c2dPtr->instanceOf<B>() << std::endl;
  std::cout << "c2dPtr->instanceOf<C>(): expected=1, value=" << c2dPtr->instanceOf<C>() << std::endl;
  std::cout << "c2dPtr->instanceOf<D>(): expected=1, value=" << c2dPtr->instanceOf<D>() << std::endl;
  std::cout << std::endl;
  std::cout << "a2dPtr->instanceOf<A>(): expected=1, value=" << a2dPtr->instanceOf<A>() << std::endl;
  std::cout << "a2dPtr->instanceOf<B>(): expected=0, value=" << a2dPtr->instanceOf<B>() << std::endl;
  std::cout << "a2dPtr->instanceOf<C>(): expected=1, value=" << a2dPtr->instanceOf<C>() << std::endl;
  std::cout << "a2dPtr->instanceOf<D>(): expected=1, value=" << a2dPtr->instanceOf<D>() << std::endl;

  delete a2aPtr;
  delete a2bPtr;
  delete c2dPtr;

  return 0;
}

Output:

a2aPtr->instanceOf<A>(): expected=1, value=1
a2aPtr->instanceOf<B>(): expected=0, value=0
a2aPtr->instanceOf<C>(): expected=0, value=0
a2aPtr->instanceOf<D>(): expected=0, value=0

a2bPtr->instanceOf<A>(): expected=1, value=1
a2bPtr->instanceOf<B>(): expected=1, value=1
a2bPtr->instanceOf<C>(): expected=0, value=0
a2bPtr->instanceOf<D>(): expected=0, value=0

a2cPtr->instanceOf<A>(): expected=1, value=1
a2cPtr->instanceOf<B>(): expected=0, value=0
a2cPtr->instanceOf<C>(): expected=1, value=1
a2cPtr->instanceOf<D>(): expected=0, value=0

c2dPtr->instanceOf<A>(): expected=1, value=1
c2dPtr->instanceOf<B>(): expected=0, value=0
c2dPtr->instanceOf<C>(): expected=1, value=1
c2dPtr->instanceOf<D>(): expected=1, value=1

a2dPtr->instanceOf<A>(): expected=1, value=1
a2dPtr->instanceOf<B>(): expected=0, value=0
a2dPtr->instanceOf<C>(): expected=1, value=1
a2dPtr->instanceOf<D>(): expected=1, value=1

Performance

The most interesting question which now arises is, if this evil stuff is more efficient than the usage of dynamic_cast. Therefore I've written a very basic performance measurement app.

InstanceOfPerformance.cpp

#include <chrono>
#include <iostream>
#include <string>
#include "DemoClassHierarchy.hpp"

template <typename Base, typename Derived, typename Duration>
Duration instanceOfMeasurement(unsigned _loopCycles) {
  auto start = std::chrono::high_resolution_clock::now();
  volatile bool isInstanceOf = false;
  for (unsigned i = 0; i < _loopCycles; ++i) {
    Base *ptr = new Derived;
    isInstanceOf = ptr->template instanceOf<Derived>();
    delete ptr;
  }
  auto end = std::chrono::high_resolution_clock::now();
  return std::chrono::duration_cast<Duration>(end - start);
}

template <typename Base, typename Derived, typename Duration>
Duration dynamicCastMeasurement(unsigned _loopCycles) {
  auto start = std::chrono::high_resolution_clock::now();
  volatile bool isInstanceOf = false;
  for (unsigned i = 0; i < _loopCycles; ++i) {
    Base *ptr = new Derived;
    isInstanceOf = dynamic_cast<Derived *>(ptr) != nullptr;
    delete ptr;
  }
  auto end = std::chrono::high_resolution_clock::now();
  return std::chrono::duration_cast<Duration>(end - start);
}

int main() {
  unsigned testCycles = 10000000;
  std::string unit = " us";
  using DType = std::chrono::microseconds;

  std::cout << "InstanceOf performance(A->D)  : " << instanceOfMeasurement<A, D, DType>(testCycles).count() << unit
            << std::endl;
  std::cout << "InstanceOf performance(A->C)  : " << instanceOfMeasurement<A, C, DType>(testCycles).count() << unit
            << std::endl;
  std::cout << "InstanceOf performance(A->B)  : " << instanceOfMeasurement<A, B, DType>(testCycles).count() << unit
            << std::endl;
  std::cout << "InstanceOf performance(A->A)  : " << instanceOfMeasurement<A, A, DType>(testCycles).count() << unit
            << "\n"
            << std::endl;
  std::cout << "DynamicCast performance(A->D) : " << dynamicCastMeasurement<A, D, DType>(testCycles).count() << unit
            << std::endl;
  std::cout << "DynamicCast performance(A->C) : " << dynamicCastMeasurement<A, C, DType>(testCycles).count() << unit
            << std::endl;
  std::cout << "DynamicCast performance(A->B) : " << dynamicCastMeasurement<A, B, DType>(testCycles).count() << unit
            << std::endl;
  std::cout << "DynamicCast performance(A->A) : " << dynamicCastMeasurement<A, A, DType>(testCycles).count() << unit
            << "\n"
            << std::endl;
  return 0;
}

The results vary and are essentially based on the degree of compiler optimization. Compiling the performance measurement program using g++ -std=c++11 -O0 -o instanceof-performance InstanceOfPerformance.cpp the output on my local machine was:

InstanceOf performance(A->D)  : 699638 us
InstanceOf performance(A->C)  : 642157 us
InstanceOf performance(A->B)  : 671399 us
InstanceOf performance(A->A)  : 626193 us

DynamicCast performance(A->D) : 754937 us
DynamicCast performance(A->C) : 706766 us
DynamicCast performance(A->B) : 751353 us
DynamicCast performance(A->A) : 676853 us

Mhm, this result was very sobering, because the timings demonstrates that the new approach is not much faster compared to the dynamic_cast approach. It is even less efficient for the special test case which tests if a pointer of A is an instance ofA. BUT the tide turns by tuning our binary using compiler otpimization. The respective compiler command is g++ -std=c++11 -O3 -o instanceof-performance InstanceOfPerformance.cpp. The result on my local machine was amazing:

InstanceOf performance(A->D)  : 3035 us
InstanceOf performance(A->C)  : 5030 us
InstanceOf performance(A->B)  : 5250 us
InstanceOf performance(A->A)  : 3021 us

DynamicCast performance(A->D) : 666903 us
DynamicCast performance(A->C) : 698567 us
DynamicCast performance(A->B) : 727368 us
DynamicCast performance(A->A) : 3098 us

If you are not reliant on multiple inheritance, are no opponent of good old C macros, RTTI and template metaprogramming and are not too lazy to add some small instructions to the classes of your class hierarchy, then this approach can boost your application a little bit with respect to its performance, if you often end up with checking the instance of a pointer. But use it with caution. There is no warranty for the correctness of this approach.

Note: All demos were compiled using clang (Apple LLVM version 9.0.0 (clang-900.0.39.2)) under macOS Sierra on a MacBook Pro Mid 2012.

Edit: I've also tested the performance on a Linux machine using gcc (Ubuntu 5.4.0-6ubuntu1~16.04.9) 5.4.0 20160609. On this platform the perfomance benefit was not so significant as on macOs with clang.

Output (without compiler optimization):

InstanceOf performance(A->D)  : 390768 us
InstanceOf performance(A->C)  : 333994 us
InstanceOf performance(A->B)  : 334596 us
InstanceOf performance(A->A)  : 300959 us

DynamicCast performance(A->D) : 331942 us
DynamicCast performance(A->C) : 303715 us
DynamicCast performance(A->B) : 400262 us
DynamicCast performance(A->A) : 324942 us

Output (with compiler optimization):

InstanceOf performance(A->D)  : 209501 us
InstanceOf performance(A->C)  : 208727 us
InstanceOf performance(A->B)  : 207815 us
InstanceOf performance(A->A)  : 197953 us

DynamicCast performance(A->D) : 259417 us
DynamicCast performance(A->C) : 256203 us
DynamicCast performance(A->B) : 261202 us
DynamicCast performance(A->A) : 193535 us

A default document is not configured for the requested URL, and directory browsing is not enabled on the server

In my case, I had to install the Microsoft.Owin.Host.SystemWeb package.

I was getting the same message as you did, but then noticed I couldn't even hit a breakpoint in Startup.cs which then let me to this SO thread.

How to load html string in a webview?

I had the same requirement and I have done this in following way.You also can try out this..

Use loadData method

web.loadData("<p style='text-align:center'><img class='aligncenter size-full wp-image-1607' title='' src="+movImage+" alt='' width='240px' height='180px' /></p><p><center><U><H2>"+movName+"("+movYear+")</H2></U></center></p><p><strong>Director : </strong>"+movDirector+"</p><p><strong>Producer : </strong>"+movProducer+"</p><p><strong>Character : </strong>"+movActedAs+"</p><p><strong>Summary : </strong>"+movAnecdotes+"</p><p><strong>Synopsis : </strong>"+movSynopsis+"</p>\n","text/html", "UTF-8");

movDirector movProducer like all are my string variable.

In short i retain custom styling for my url.

Oracle PL/SQL - Raise User-Defined Exception With Custom SQLERRM

create or replace PROCEDURE PROC_USER_EXP 
AS
duplicate_exp EXCEPTION;
PRAGMA EXCEPTION_INIT( duplicate_exp, -20001 );
LVCOUNT NUMBER;
BEGIN
  SELECT COUNT(*) INTO LVCOUNT FROM JOBS WHERE JOB_TITLE='President';
  IF LVCOUNT >1 THEN 
   raise_application_error( -20001, 'Duplicate president customer excetpion' );
  END IF;

  EXCEPTION 
  WHEN duplicate_exp THEN 
  DBMS_OUTPUT.PUT_LINE(sqlerrm);
END PROC_USER_EXP;

ORACLE 11g output will be like this:

Connecting to the database HR. 
ORA-20001: Duplicate president customer excetpion 
Process exited. 
Disconnecting from the database HR

select from one table, insert into another table oracle sql query

try this query below:

Insert into tab1 (tab1.column1,tab1.column2) 
select tab2.column1, 'hard coded  value' 
from tab2 
where tab2.column='value';

How to implement linear interpolation?

Instead of extrapolating off the ends, you could return the extents of the y_list. Most of the time your application is well behaved, and the Interpolate[x] will be in the x_list. The (presumably) linear affects of extrapolating off the ends may mislead you to believe that your data is well behaved.

  • Returning a non-linear result (bounded by the contents of x_list and y_list) your program's behavior may alert you to an issue for values greatly outside x_list. (Linear behavior goes bananas when given non-linear inputs!)

  • Returning the extents of the y_list for Interpolate[x] outside of x_list also means you know the range of your output value. If you extrapolate based on x much, much less than x_list[0] or x much, much greater than x_list[-1], your return result could be outside of the range of values you expected.

    def __getitem__(self, x):
        if x <= self.x_list[0]:
            return self.y_list[0]
        elif x >= self.x_list[-1]:
            return self.y_list[-1]
        else:
            i = bisect_left(self.x_list, x) - 1
            return self.y_list[i] + self.slopes[i] * (x - self.x_list[i])
    

java.lang.VerifyError: Expecting a stackmap frame at branch target JDK 1.7

If you are building the code yourself, then this issue could be overcome by giving "-target 1.5" to the java compiler (or by setting the corresponding option in your IDE or your build config).

How to check if an app is installed from a web-page on an iPhone?

The date solution is much better than others, I had to increment the time on 50 like that this is a Tweeter example:

//on click or your event handler..
var twMessage = "Your Message to share";
var now = new Date().valueOf();
setTimeout(function () {
   if (new Date().valueOf() - now > 100) return;
   var twitterUrl = "https://twitter.com/share?text="+twMessage;
   window.open(twitterUrl, '_blank');
}, 50);
window.location = "twitter://post?message="+twMessage;

the only problem on Mobile IOS Safari is when you don't have the app installed on device, and so Safari show an alert that autodismiss when the new url is opened, anyway is a good solution for now!

javascript code to check special characters

Did you write return true somewhere? You should have written it, otherwise function returns nothing and program may think that it's false, too.

function isValid(str) {
    var iChars = "~`!#$%^&*+=-[]\\\';,/{}|\":<>?";

    for (var i = 0; i < str.length; i++) {
       if (iChars.indexOf(str.charAt(i)) != -1) {
           alert ("File name has special characters ~`!#$%^&*+=-[]\\\';,/{}|\":<>? \nThese are not allowed\n");
           return false;
       }
    }
    return true;
}

I tried this in my chrome console and it worked well.

Get public/external IP address?

I find most of the other answers lacking as they assume that any returned string must be the IP, but doesn't really check for it. This is my solution that I'm currently using. It will only return a valid IP or null if none is found.

public class WhatsMyIp
{
    public static IPAddress PublicIp { get; private set; }
    static WhatsMyIp()
    {
        PublicIp = GetMyIp();
    }

    public static IPAddress GetMyIp()
    {
        List<string> services = new List<string>()
        {
            "https://ipv4.icanhazip.com",
            "https://api.ipify.org",
            "https://ipinfo.io/ip",
            "https://checkip.amazonaws.com",
            "https://wtfismyip.com/text",
            "http://icanhazip.com"
        };
        using (var webclient = new WebClient())
            foreach (var service in services)
            {
                try { return IPAddress.Parse(webclient.DownloadString(service)); } catch { }
            }
        return null;
    }
}

Android: Getting a file URI from a content URI?

Inspired answers are Jason LaBrun & Darth Raven. Trying already answered approaches led me to below solution which may mostly cover cursor null cases & conversion from content:// to file://

To convert file, read&write the file from gained uri

public static Uri getFilePathFromUri(Uri uri) throws IOException {
    String fileName = getFileName(uri);
    File file = new File(myContext.getExternalCacheDir(), fileName);
    file.createNewFile();
    try (OutputStream outputStream = new FileOutputStream(file);
         InputStream inputStream = myContext.getContentResolver().openInputStream(uri)) {
        FileUtil.copyStream(inputStream, outputStream); //Simply reads input to output stream
        outputStream.flush();
    }
    return Uri.fromFile(file);
}

To get filename use, it will cover cursor null case

public static String getFileName(Uri uri) {
    String fileName = getFileNameFromCursor(uri);
    if (fileName == null) {
        String fileExtension = getFileExtension(uri);
        fileName = "temp_file" + (fileExtension != null ? "." + fileExtension : "");
    } else if (!fileName.contains(".")) {
        String fileExtension = getFileExtension(uri);
        fileName = fileName + "." + fileExtension;
    }
    return fileName;
}

There is good option to converting from mime type to file extention

 public static String getFileExtension(Uri uri) {
    String fileType = myContext.getContentResolver().getType(uri);
    return MimeTypeMap.getSingleton().getExtensionFromMimeType(fileType);
}

Cursor to obtain name of file

public static String getFileNameFromCursor(Uri uri) {
    Cursor fileCursor = myContext.getContentResolver().query(uri, new String[]{OpenableColumns.DISPLAY_NAME}, null, null, null);
    String fileName = null;
    if (fileCursor != null && fileCursor.moveToFirst()) {
        int cIndex = fileCursor.getColumnIndex(OpenableColumns.DISPLAY_NAME);
        if (cIndex != -1) {
            fileName = fileCursor.getString(cIndex);
        }
    }
    return fileName;
}

How can I verify if a Windows Service is running

Here you get all available services and their status in your local machine.

ServiceController[] services = ServiceController.GetServices();
foreach(ServiceController service in services)
{
    Console.WriteLine(service.ServiceName+"=="+ service.Status);
}

You can Compare your service with service.name property inside loop and you get status of your service. For details go with the http://msdn.microsoft.com/en-us/library/system.serviceprocess.servicecontroller.aspx also http://msdn.microsoft.com/en-us/library/microsoft.windows.design.servicemanager(v=vs.90).aspx

Open mvc view in new window from controller

You're asking the wrong question. The codebehind (controller) has nothing to do with what the frontend does. In fact, that's the strength of MVC -- you separate the code/concept from the view.

If you want an action to open in a new window, then links to that action need to tell the browser to open a new window when clicked.

A pseudo example: <a href="NewWindow" target="_new">Click Me</a>

And that's all there is to it. Set the target of links to that action.

System.Net.WebException HTTP status code

Maybe something like this...

try
{
    // ...
}
catch (WebException ex)
{
    if (ex.Status == WebExceptionStatus.ProtocolError)
    {
        var response = ex.Response as HttpWebResponse;
        if (response != null)
        {
            Console.WriteLine("HTTP Status Code: " + (int)response.StatusCode);
        }
        else
        {
            // no http status code available
        }
    }
    else
    {
        // no http status code available
    }
}

CSS technique for a horizontal line with words in the middle

Solution for IE8 and newer...

Issues worth noting:

Using background-color to mask a border might not be the best solution. If you have a complex (or unknown) background color (or image), masking will ultimately fail. Also, if you resize the text, you'll notice that white background color (or whatever you set) will start covering up the text on the line above (or below).

You also don't want to "guesstimate" how wide the the sections are either, because it makes the styles very inflexible and almost impossible to implement on a responsive site where the width of the content is changing.

Solution:

(View JSFiddle)

Instead of "masking" a border with a background-color, use your display property.

HTML

<div class="group">
    <div class="item line"></div>
    <div class="item text">This is a test</div>
    <div class="item line"></div>
</div>

CSS

.group { display: table; width: 100%; }
.item { display: table-cell; }
.text { white-space: nowrap; width: 1%; padding: 0 10px; }
.line { border-bottom: 1px solid #000; position: relative; top: -.5em; }

Resize your text by placing your font-size property on the .group element.

Limitations:

  • No multi-line text. Single lines only.
  • HTML markup isn't as elegant
  • top property on .line element needs to be half of line-height. So, if you have a line-height of 1.5em, then the top should be -.75em. This is a limitation because it's not automated, and if you are applying these styles on elements with different line-heights, then you might need to reapply your line-height style.

For me, these limitations outweigh the "issues" I noted at the beginning of my answer for most implementations.

User Authentication in ASP.NET Web API

I am working on a MVC5/Web API project and needed to be able to get authorization for the Web Api methods. When my index view is first loaded I make a call to the 'token' Web API method which I believe is created automatically.

The client side code (CoffeeScript) to get the token is:

getAuthenticationToken = (username, password) ->
    dataToSend = "username=" + username + "&password=" + password
    dataToSend += "&grant_type=password"
    $.post("/token", dataToSend).success saveAccessToken

If successful the following is called, which saves the authentication token locally:

saveAccessToken = (response) ->
    window.authenticationToken = response.access_token

Then if I need to make an Ajax call to a Web API method that has the [Authorize] tag I simply add the following header to my Ajax call:

{ "Authorization": "Bearer " + window.authenticationToken }

How to push changes to github after jenkins build completes?

The git checkout master of the answer by Woland isn't needed. Instead use the "Checkout to specific local branch" in the "Additional Behaviors" section to set the "Branch name" to master.

The git commit -am "blah" is still needed.

Now you can use the "Git Publisher" under "Post-build Actions" to push the changes. Be sure to specify the "Branches" to push ("Branch to push" = master, "Target remote name" = origin).

"Merge Results" isn't needed.

How do I enumerate the properties of a JavaScript object?

I'm still a beginner in JavaScript, but I wrote a small function to recursively print all the properties of an object and its children:

getDescription(object, tabs) {
  var str = "{\n";
  for (var x in object) {
      str += Array(tabs + 2).join("\t") + x + ": ";
      if (typeof object[x] === 'object' && object[x]) {
        str += this.getDescription(object[x], tabs + 1);
      } else {
        str += object[x];
      }
      str += "\n";
  }
  str += Array(tabs + 1).join("\t") + "}";
  return str;
}

IOPub data rate exceeded in Jupyter notebook (when viewing image)

By typing 'jupyter notebook --NotebookApp.iopub_data_rate_limit=1.0e10' in Anaconda PowerShell or prompt, the Jupyter notebook will open with the new configuration. Try now to run your query.

How to test whether a service is running from the command line

Try

sc query state= all 

for a list of services and whether they are running or not.

How do I rename both a Git local and remote branch name?

If you have named a branch incorrectly AND pushed this to the remote repository follow these steps to rename that branch (based on this article):

  1. Rename your local branch:

    • If you are on the branch you want to rename:
      git branch -m new-name

    • If you are on a different branch:
      git branch -m old-name new-name

  2. Delete the old-name remote branch and push the new-name local branch:
    git push origin :old-name new-name

  3. Reset the upstream branch for the new-name local branch:
    Switch to the branch and then:
    git push origin -u new-name

Retrieving Property name from lambda expression

Well, there's no need to call .Name.ToString(), but broadly that is about it, yes. The only consideration you might need is whether x.Foo.Bar should return "Foo", "Bar", or an exception - i.e. do you need to iterate at all.

(re comment) for more on flexible sorting, see here.

In Java, how do I call a base class's method from the overriding method in a derived class?

// Using super keyword access parent class variable
class test {
    int is,xs;

    test(int i,int x) {
        is=i;
        xs=x;
        System.out.println("super class:");
    }
}

class demo extends test {
    int z;

    demo(int i,int x,int y) {
        super(i,x);
        z=y;
        System.out.println("re:"+is);
        System.out.println("re:"+xs);
        System.out.println("re:"+z);
    }
}

class free{
    public static void main(String ar[]){
        demo d=new demo(4,5,6);
    }
}

Having trouble setting working directory

This may help... use the following code and browse the folder you want to set as the working folder

setwd(choose.dir())

How to read large text file on windows?

While Large Text File Viewer works great for just looking at a large file (and is free!), if the file is either a delimited or fixed-width file, then you should check out File Query. Not only can it open a file of any size (I have personally opened a 280GB file, but it can go larger), but it lets you query the file as though it was in a database as well, finding out any sort of information you could want from it.

It is not free though, so it is more for people that work with large files a lot, but if you have a one-off problem, you can just use the 30-day trial for free.

How to start Activity in adapter?

callback from adapter to activity can be done using registering listener in form of interface: Make an interface:

      public MyInterface{
         public void  yourmethod(//incase needs parameters );
         }

In Adapter Let's Say MyAdapter:

    public MyAdapter extends BaseAdapter{
       private MyInterface listener;

    MyAdapter(Context context){
        try {
            this. listener = (( MyInterface ) context);
              } catch (ClassCastException e) {
               throw new ClassCastException("Activity must implement MyInterface");
          }

//do this where u need to fire listener l

          try {
                listener . yourmethod ();
            } catch (ClassCastException exception) {
               // do something
            }

      In Activity Implement your method:


         MyActivity extends AppCompatActivity implements MyInterface{

                yourmethod(){
                //do whatever you want
                     }
                     }

ERROR 2002 (HY000): Can't connect to local MySQL server through socket '/var/run/mysqld/mysql.sock' (2)

Simple: run these codes:::

 1:: ls -lart/var/run/my*

   2::mkdir /var/run/mysqld

    3::touch /var/run/mysqld/mysqld.sock
    4:ls -lart /var/run/mysqld
    5::chown -R mysql /var/run/mysqld
    6::ls -lart /var/run/mysqld
REstart your mysql server

then finaly type mysql -u root or mysql -u root -p and press enter key. thanks

Finding the second highest number in array

public class secondLargestElement 
{
    public static void main(String[] args) 
    {
        int []a1={1,0};
        secondHigh(a1);
    }

    public static void secondHigh(int[] arr)
    {
        try
        {
            int highest,sec_high;
            highest=arr[0];
            sec_high=arr[1];

                for(int i=1;i<arr.length;i++)
                {
                    if(arr[i]>highest)
                    {           
                        sec_high=highest;
                        highest=arr[i]; 
                    }
                    else 
                    // The first condition before the || is to make sure that second highest is not actually same as the highest , think 
                        // about {5,4,5}, you don't want the last  5 to be reported as the sec_high
                        // The other half after || says if the first two elements are same then also replace the sec_high with incoming integer
                        // Think about {5,5,4}
                    if(arr[i]>sec_high && arr[i]<highest || highest==sec_high)
                        sec_high=arr[i];
                }
            //System.out.println("high="+highest +"sec"+sec_high);
            if(highest==sec_high)
                System.out.println("All the elements in the input array are same");
             else
                 System.out.println("The second highest element in the array is:"+ sec_high);

         }

        catch(ArrayIndexOutOfBoundsException e)
        {
        System.out.println("Not enough elements in the array");
        //e.printStackTrace();
        }
    }
}

Difference between del, remove, and pop on lists

The remove operation on a list is given a value to remove. It searches the list to find an item with that value and deletes the first matching item it finds. It is an error if there is no matching item, raises a ValueError.

>>> x = [1, 0, 0, 0, 3, 4, 5]
>>> x.remove(4)
>>> x
[1, 0, 0, 0, 3, 5]
>>> del x[7]
Traceback (most recent call last):
  File "<pyshell#1>", line 1, in <module>
    del x[7]
IndexError: list assignment index out of range

The del statement can be used to delete an entire list. If you have a specific list item as your argument to del (e.g. listname[7] to specifically reference the 8th item in the list), it'll just delete that item. It is even possible to delete a "slice" from a list. It is an error if there index out of range, raises a IndexError.

>>> x = [1, 2, 3, 4]
>>> del x[3]
>>> x
[1, 2, 3]
>>> del x[4]
Traceback (most recent call last):
  File "<pyshell#1>", line 1, in <module>
    del x[4]
IndexError: list assignment index out of range

The usual use of pop is to delete the last item from a list as you use the list as a stack. Unlike del, pop returns the value that it popped off the list. You can optionally give an index value to pop and pop from other than the end of the list (e.g listname.pop(0) will delete the first item from the list and return that first item as its result). You can use this to make the list behave like a queue, but there are library routines available that can provide queue operations with better performance than pop(0) does. It is an error if there index out of range, raises a IndexError.

>>> x = [1, 2, 3] 
>>> x.pop(2) 
3 
>>> x 
[1, 2]
>>> x.pop(4)
Traceback (most recent call last):
  File "<pyshell#1>", line 1, in <module>
    x.pop(4)
IndexError: pop index out of range

See collections.deque for more details.

How to compile and run C in sublime text 3?

The latest build of the sublime even allows the direct command instead of double quotes. Try the below code for the build system

{
    "cmd" : ["gcc $file_name -o ${file_base_name} && ./${file_base_name}"],
    "selector" : "source.c",
    "shell": true,
    "working_dir" : "$file_path",
}

Create line after text with css

This is the most easy way I found to achieve the result: Just use hr tag before the text, and set the margin top for text. Very short and easy to understand! jsfiddle

_x000D_
_x000D_
h2 {_x000D_
  background-color: #ffffff;_x000D_
  margin-top: -22px;_x000D_
  width: 25%;_x000D_
}_x000D_
_x000D_
hr {_x000D_
  border: 1px solid #e9a216;_x000D_
}
_x000D_
<br>_x000D_
_x000D_
<hr>_x000D_
<h2>ABOUT US</h2>
_x000D_
_x000D_
_x000D_

React Router Pass Param to Component

In addition to Alexander Lunas answer ... If you want to add more than one argument just use:

<Route path="/details/:id/:title" component={DetailsPage}/>

export default class DetailsPage extends Component {
  render() {
    return(
      <div>
        <h2>{this.props.match.params.id}</h2>
        <h3>{this.props.match.params.title}</h3>
      </div>
    )
  }
}

Set 4 Space Indent in Emacs in Text Mode

(setq tab-width 4)
(setq tab-stop-list '(4 8 12 16 20 24 28 32 36 40 44 48 52 56 60 64 68 72 76 80))
(setq indent-tabs-mode nil)

syntax error, unexpected T_VARIABLE

If that is the entire line, it very well might be because you are missing a ; at the end of the line.

How to use Class<T> in Java?

All we know is "All instances of a any class shares the same java.lang.Class object of that type of class"

e.g)

Student a = new Student();
Student b = new Student();

Then a.getClass() == b.getClass() is true.

Now assume

Teacher t = new Teacher();

without generics the below is possible.

Class studentClassRef = t.getClass();

But this is wrong now ..?

e.g) public void printStudentClassInfo(Class studentClassRef) {} can be called with Teacher.class

This can be avoided using generics.

Class<Student> studentClassRef = t.getClass(); //Compilation error.

Now what is T ?? T is type parameters (also called type variables); delimited by angle brackets (<>), follows the class name.
T is just a symbol, like a variable name (can be any name) declared during writing of the class file. Later that T will be substituted with
valid Class name during initialization (HashMap<String> map = new HashMap<String>();)

e.g) class name<T1, T2, ..., Tn>

So Class<T> represents a class object of specific class type 'T'.

Assume that your class methods has to work with unknown type parameters like below

/**
 * Generic version of the Car class.
 * @param <T> the type of the value
 */
public class Car<T> {
    // T stands for "Type"
    private T t;

    public void set(T t) { this.t = t; }
    public T get() { return t; }
}

Here T can be used as String type as CarName

OR T can be used as Integer type as modelNumber,

OR T can be used as Object type as valid car instance.

Now here the above is the simple POJO which can be used differently at runtime.
Collections e.g) List, Set, Hashmap are best examples which will work with different objects as per the declaration of T, but once we declared T as String
e.g) HashMap<String> map = new HashMap<String>(); Then it will only accept String Class instance objects.

Generic Methods

Generic methods are methods that introduce their own type parameters. This is similar to declaring a generic type, but the type parameter's scope is limited to the method where it is declared. Static and non-static generic methods are allowed, as well as generic class constructors.

The syntax for a generic method includes a type parameter, inside angle brackets, and appears before the method's return type. For generic methods, the type parameter section must appear before the method's return type.

 class Util {
    // Generic static method
    public static <K, V, Z, Y> boolean compare(Pair<K, V> p1, Pair<Z, Y> p2) {
        return p1.getKey().equals(p2.getKey()) &&
               p1.getValue().equals(p2.getValue());
    }
}

 class Pair<K, V> {

    private K key;
    private V value;
}

Here <K, V, Z, Y> is the declaration of types used in the method arguments which should before the return type which is boolean here.

In the below; type declaration <T> is not required at method level, since it is already declared at class level.

class MyClass<T> {
   private  T myMethod(T a){
       return  a;
   }
}

But below is wrong as class-level type parameters K, V, Z, and Y cannot be used in a static context (static method here).

class Util <K, V, Z, Y>{
    // Generic static method
    public static  boolean compare(Pair<K, V> p1, Pair<Z, Y> p2) {
        return p1.getKey().equals(p2.getKey()) &&
               p1.getValue().equals(p2.getValue());
    }
}

OTHER VALID SCENARIOS ARE

class MyClass<T> {

        //Type declaration <T> already done at class level
        private  T myMethod(T a){
            return  a;
        }

        //<T> is overriding the T declared at Class level;
        //So There is no ClassCastException though a is not the type of T declared at MyClass<T>. 
        private <T> T myMethod1(Object a){
                return (T) a;
        }

        //Runtime ClassCastException will be thrown if a is not the type T (MyClass<T>).  
        private T myMethod1(Object a){
                return (T) a;
        }       

        // No ClassCastException        
        // MyClass<String> obj= new MyClass<String>();
        // obj.myMethod2(Integer.valueOf("1"));
        // Since type T is redefined at this method level.
        private <T> T myMethod2(T a){
            return  a;
        }

        // No ClassCastException for the below
        // MyClass<String> o= new MyClass<String>();
        // o.myMethod3(Integer.valueOf("1").getClass())
        // Since <T> is undefined within this method; 
        // And MyClass<T> don't have impact here
        private <T> T myMethod3(Class a){
            return (T) a;
        }

        // ClassCastException for o.myMethod3(Integer.valueOf("1").getClass())
        // Should be o.myMethod3(String.valueOf("1").getClass())
    private  T myMethod3(Class a){
        return (T) a;
    }


        // Class<T> a :: a is Class object of type T
        //<T> is overriding of class level type declaration; 
        private <T> Class<T> myMethod4(Class<T> a){
            return  a;
        }
    }

And finally Static method always needs explicit <T> declaration; It wont derive from class level Class<T>. This is because of Class level T is bound with instance.

Also read Restrictions on Generics

Wildcards and Subtyping

type argument for a generic method

When to use Interface and Model in TypeScript / Angular

Use Class instead of Interface that is what I discovered after all my research.

Why? A class alone is less code than a class-plus-interface. (anyway you may require a Class for data model)

Why? A class can act as an interface (use implements instead of extends).

Why? An interface-class can be a provider lookup token in Angular dependency injection.

from Angular Style Guide

Basically a Class can do all, what an Interface will do. So may never need to use an Interface.

How to access your website through LAN in ASP.NET

I'm not sure how stuck you are:

You must have a web server (Windows comes with one called IIS, but it may not be installed)

  1. Make sure you actually have IIS installed! Try typing http://localhost/ in your browser and see what happens. If nothing happens it means that you may not have IIS installed. See Installing IIS
  2. Set up IIS How to set up your first IIS Web site
  3. You may even need to Install the .NET Framework (or your server will only serve static html pages, and not asp.net pages)

Installing your application

Once you have done that, you can more or less just copy your application to c:\wwwroot\inetpub\. Read Installing ASP.NET Applications (IIS 6.0) for more information

Accessing the web site from another machine

In theory, once you have a web server running, and the application installed, you only need the IP address of your web server to access the application.

To find your IP address try: Start -> Run -> type cmd (hit ENTER) -> type ipconfig (hit ENTER)

Once

  • you have the IP address AND
  • IIS running AND
  • the application is installed

you can access your website from another machine in your LAN by just typing in the IP Address of you web server and the correct path to your application.

If you put your application in a directory called NewApp, you will need to type something like http://your_ip_address/NewApp/default.aspx

Turn off your firewall

If you do have a firewall turn it off while you try connecting for the first time, you can sort that out later.

How do I tell Gradle to use specific JDK version?

If you are using Kotlin DSL, then in build.gradle.kts add:

tasks.withType<JavaCompile> {
    options.isFork = true
    options.forkOptions.javaHome = File("C:\\bin\\jdk-13.0.1\\")
}

Of course, I'm assuming that you have Windows OS and javac compiler is in path C:\bin\jdk-13.0.1\bin\javac. For Linux OS will be similarly.

What is the curl error 52 "empty reply from server"?

My case was due to SSL certificate expiration

Two inline-block, width 50% elements wrap to second line

You can remove the whitespaces via css using white-space so you can keep your pretty HTML layout. Don't forget to set the white-space back to normal again if you want your text to wrap inside the columns.

Tested in IE9, Chrome 18, FF 12

.container { white-space: nowrap; }
.column { display: inline-block; width: 50%; white-space: normal; }

<div class="container">
  <div class="column">text that can wrap</div>
  <div class="column">text that can wrap</div>
</div>

How do I fire an event when a iframe has finished loading in jQuery?

Using both jquery Load and Ready neither seemed to really match when the iframe was TRULY ready.

I ended up doing something like this

$('#iframe').ready(function () {
    $("#loader").fadeOut(2500, function (sender) {
        $(sender).remove();
    });
});

Where #loader is an absolutely positioned div over top the iframe with a spinner gif.

Array vs. Object efficiency in JavaScript

I had a similar problem that I am facing where I need to store live candlesticks from an event source limited to x items. I could have them stored in an object where the timestamp of each candle would act as the key and the candle itself would act as the value. Another possibility was that I could store it in an array where each item was the candle itself. One problem about live candles is that they keep sending updates on the same timestamp where the latest update holds the most recent data therefore you either update an existing item or add a new one. So here is a nice benchmark that attempts to combine all 3 possibilities. Arrays in the solution below are atleast 4x faster on average. Feel free to play

"use strict";

const EventEmitter = require("events");
let candleEmitter = new EventEmitter();

//Change this to set how fast the setInterval should run
const frequency = 1;

setInterval(() => {
    // Take the current timestamp and round it down to the nearest second
    let time = Math.floor(Date.now() / 1000) * 1000;
    let open = Math.random();
    let high = Math.random();
    let low = Math.random();
    let close = Math.random();
    let baseVolume = Math.random();
    let quoteVolume = Math.random();

    //Clear the console everytime before printing fresh values
    console.clear()

    candleEmitter.emit("candle", {
        symbol: "ABC:DEF",
        time: time,
        open: open,
        high: high,
        low: low,
        close: close,
        baseVolume: baseVolume,
        quoteVolume: quoteVolume
    });



}, frequency)

// Test 1 would involve storing the candle in an object
candleEmitter.on('candle', storeAsObject)

// Test 2 would involve storing the candle in an array
candleEmitter.on('candle', storeAsArray)

//Container for the object version of candles
let objectOhlc = {}

//Container for the array version of candles
let arrayOhlc = {}

//Store a max 30 candles and delete older ones
let limit = 30

function storeAsObject(candle) {

    //measure the start time in nanoseconds
    const hrtime1 = process.hrtime()
    const start = hrtime1[0] * 1e9 + hrtime1[1]

    const { symbol, time } = candle;

    // Create the object structure to store the current symbol
    if (typeof objectOhlc[symbol] === 'undefined') objectOhlc[symbol] = {}

    // The timestamp of the latest candle is used as key with the pair to store this symbol
    objectOhlc[symbol][time] = candle;

    // Remove entries if we exceed the limit
    const keys = Object.keys(objectOhlc[symbol]);
    if (keys.length > limit) {
        for (let i = 0; i < (keys.length - limit); i++) {
            delete objectOhlc[symbol][keys[i]];
        }
    }

    //measure the end time in nano seocnds
    const hrtime2 = process.hrtime()
    const end = hrtime2[0] * 1e9 + hrtime2[1]

    console.log("Storing as objects", end - start, Object.keys(objectOhlc[symbol]).length)
}

function storeAsArray(candle) {

    //measure the start time in nanoseconds
    const hrtime1 = process.hrtime()
    const start = hrtime1[0] * 1e9 + hrtime1[1]

    const { symbol, time } = candle;
    if (typeof arrayOhlc[symbol] === 'undefined') arrayOhlc[symbol] = []

    //Get the bunch of candles currently stored
    const candles = arrayOhlc[symbol];

    //Get the last candle if available
    const lastCandle = candles[candles.length - 1] || {};

    // Add a new entry for the newly arrived candle if it has a different timestamp from the latest one we storeds
    if (time !== lastCandle.time) {
        candles.push(candle);
    }

    //If our newly arrived candle has the same timestamp as the last stored candle, update the last stored candle
    else {
        candles[candles.length - 1] = candle
    }

    if (candles.length > limit) {
        candles.splice(0, candles.length - limit);
    }

    //measure the end time in nano seocnds
    const hrtime2 = process.hrtime()
    const end = hrtime2[0] * 1e9 + hrtime2[1]


    console.log("Storing as array", end - start, arrayOhlc[symbol].length)
}

Conclusion 10 is the limit here

Storing as objects 4183 nanoseconds 10
Storing as array 373 nanoseconds 10

Python Dictionary Comprehension

You can use the dict.fromkeys class method ...

>>> dict.fromkeys(range(5), True)
{0: True, 1: True, 2: True, 3: True, 4: True}

This is the fastest way to create a dictionary where all the keys map to the same value.

But do not use this with mutable objects:

d = dict.fromkeys(range(5), [])
# {0: [], 1: [], 2: [], 3: [], 4: []}
d[1].append(2)
# {0: [2], 1: [2], 2: [2], 3: [2], 4: [2]} !!!

If you don't actually need to initialize all the keys, a defaultdict might be useful as well:

from collections import defaultdict
d = defaultdict(True)

To answer the second part, a dict-comprehension is just what you need:

{k: k for k in range(10)}

You probably shouldn't do this but you could also create a subclass of dict which works somewhat like a defaultdict if you override __missing__:

>>> class KeyDict(dict):
...    def __missing__(self, key):
...       #self[key] = key  # Maybe add this also?
...       return key
... 
>>> d = KeyDict()
>>> d[1]
1
>>> d[2]
2
>>> d[3]
3
>>> print(d)
{}

Delete multiple rows by selecting checkboxes using PHP

Use array notation like name="checkbox[]" in your input element. This will give you $_POST['checkbox'] as array. In the query you can utilize it as

$sql = "DELETE FROM links WHERE link_id in ";
$sql.= "('".implode("','",array_values($_POST['checkbox']))."')";

Thats one single query to delete them all.

Note: You need to escape the values passed in $_POST['checkbox'] with mysql_real_escape_string or similar to prevent SQL Injection.

How to list containers in Docker

just a convenient way of getting last n=5 containers (no matter running or not):

$ docker container ls -a -n5

How do I parse a YAML file in Ruby?

I had the same problem but also wanted to get the content of the file (after the YAML front-matter).

This is the best solution I have found:

if (md = contents.match(/^(?<metadata>---\s*\n.*?\n?)^(---\s*$\n?)/m))
  self.contents = md.post_match
  self.metadata = YAML.load(md[:metadata])
end

Source and discussion: https://practicingruby.com/articles/tricks-for-working-with-text-and-files

Finding a substring within a list in Python

I'd just use a simple regex, you can do something like this

import re
old_list = ['abc123', 'def456', 'ghi789']
new_list = [x for x in old_list if re.search('abc', x)]
for item in new_list:
    print item

Hiding a button in Javascript

<script>
    $('#btn_hide').click( function () {
      $('#btn_hide').hide();
    });
</script>
<input type="button" id="btn_hide"/>

this will be enough

How to unzip a file using the command line?

Copy the below code to a batch file and execute. Below requires Winzip to be installed/accessible from your machine. Do change variables as per your need.

@ECHO OFF
SET winzip_path="C:\Program Files\WinZip"
SET source_path="C:\Test"
SET output_path="C:\Output\"
SET log_file="C:\Test\unzip_log.txt"
SET file_name="*.zip"

cd %source_path%
echo Executing for %source_path% > %log_file%

FOR /f "tokens=*" %%G IN ('dir %file_name% /b') DO (
echo Processing : %%G
echo File_Name : %%G >> %log_file%
%winzip_path%\WINZIP32.EXE -e %%G %output_path%
)

PAUSE

Javascript logical "!==" operator?

The !== opererator tests whether values are not equal or not the same type. i.e.

var x = 5;
var y = '5';
var 1 = y !== x; // true
var 2 = y != x; // false

check if command was successful in a batch file

Most commands/programs return a 0 on success and some other value, called errorlevel, to signal an error.

You can check for this in you batch for example by:

call <THE_COMMAND_HERE>
if %ERRORLEVEL% == 0 goto :next
echo "Errors encountered during execution.  Exited with status: %errorlevel%"
goto :endofscript

:next
echo "Doing the next thing"

:endofscript
echo "Script complete"

Checking for multiple conditions using "when" on single task in ansible

The problem with your conditional is in this part sshkey_result.rc == 1, because sshkey_result does not contain rc attribute and entire conditional fails.

If you want to check if file exists check exists attribute.

Here you can read more about stat module and how to use it.

What design patterns are used in Spring framework?

Observer-Observable: it is used in ApplicationContext's event mechanism

How to add button tint programmatically

There are three options for it using setBackgroundTintList

int myColor = Color.BLACK;
  1. button.setBackgroundTintList(new ColorStateList(EMPTY, new int[] { myColor }));
  2. button.setBackgroundTintList(ColorStateList.valueOf(myColor));
  3. button.setBackgroundTintList(contextInstance.getResources().getColorStateList(R.color.my_color));

col align right

Use float-right for block elements, or text-right for inline elements:

<div class="row">
     <div class="col">left</div>
     <div class="col text-right">inline content needs to be right aligned</div>
</div>
<div class="row">
      <div class="col">left</div>
      <div class="col">
          <div class="float-right">element needs to be right aligned</div>
      </div>
</div>

http://www.codeply.com/go/oPTBdCw1JV

If float-right is not working, remember that Bootstrap 4 is now flexbox, and many elements are display:flex which can prevent float-right from working.

In some cases, the utility classes like align-self-end or ml-auto work to right align elements that are inside a flexbox container like the Bootstrap 4 .row, Card or Nav. The ml-auto (margin-left:auto) is used in a flexbox element to push elements to the right.

Bootstrap 4 align right examples

Rotating a view in Android

You could create an animation and apply it to your button view. For example:

    // Locate view
    ImageView diskView = (ImageView) findViewById(R.id.imageView3);

    // Create an animation instance
    Animation an = new RotateAnimation(0.0f, 360.0f, pivotX, pivotY);

    // Set the animation's parameters
    an.setDuration(10000);               // duration in ms
    an.setRepeatCount(0);                // -1 = infinite repeated
    an.setRepeatMode(Animation.REVERSE); // reverses each repeat
    an.setFillAfter(true);               // keep rotation after animation

    // Aply animation to image view
    diskView.setAnimation(an);

How to add an image to the emulator gallery in android studio?

Although you can have logat on a real device too, if you need to use an emulator try transferring the images through the Android Device Monitor, accessible from the toolbar in Android Studio (it's in eclipse too, of course).

Once you select the device from ADM, you can see the folders tree and copy things inside

How to generate a simple popup using jQuery

Try the Magnific Popup, it's responsive and weights just around 3KB.

Create a shortcut on Desktop

I use "Windows Script Host Object Model" reference to create shortcut.

Adding "Windows Script Host Object Model" to project references

and to create shortcut on specific location:

    void CreateShortcut(string linkPath, string filename)
    {
        // Create shortcut dir if not exists
        if (!Directory.Exists(linkPath))
            Directory.CreateDirectory(linkPath);

        // shortcut file name
        string linkName = Path.ChangeExtension(Path.GetFileName(filename), ".lnk");

        // COM object instance/props
        IWshRuntimeLibrary.WshShell shell = new IWshRuntimeLibrary.WshShell();
        IWshRuntimeLibrary.IWshShortcut sc = (IWshRuntimeLibrary.IWshShortcut)shell.CreateShortcut(linkName);
        sc.Description = "some desc";
        //shortcut.IconLocation = @"C:\..."; 
        sc.TargetPath = linkPath;
        // save shortcut to target
        sc.Save();
    }

How do I return JSON without using a template in Django?

In the case of the JSON response there is no template to be rendered. Templates are for generating HTML responses. The JSON is the HTTP response.

However, you can have HTML that is rendered from a template withing your JSON response.

html = render_to_string("some.html", some_dictionary)
serialized_data = simplejson.dumps({"html": html})
return HttpResponse(serialized_data, mimetype="application/json")

Resetting Select2 value in dropdown with reset button

you can used:

$("#d").val(null).trigger("change"); 

It's very simple and work right! If use with reset button:

$('#btnReset').click(function() {
    $("#d").val(null).trigger("change"); 
});

Get all LI elements in array

If you want all the li tags in an array even when they are in different ul tags then you can simply do

var lis = document.getElementByTagName('li'); 

and if you want to get particular div tag li's then:

var lis = document.getElementById('divID').getElementByTagName('li'); 

else if you want to search a ul first and then its li tags then you can do:

var uls = document.getElementsByTagName('ul');
for(var i=0;i<uls.length;i++){
    var lis=uls[i].getElementsByTagName('li');
    for(var j=0;j<lis.length;j++){
        console.log(lis[j].innerHTML);
    }
}

How to convert string to XML using C#

xDoc.LoadXML("<head><body><Inner> welcome </head> </Inner> <Outer> Bye</Outer>                    
                    </body></head>");

Python, Matplotlib, subplot: How to set the axis range?

You have pylab.ylim:

pylab.ylim([0,1000])

Note: The command has to be executed after the plot!

Update 2021
Since the use of pylab is now strongly discouraged by matplotlib, you should instead use pyplot:

from matplotlib import pyplot as plt
plt.ylim(0, 100) 
#corresponding function for the x-axis
plt.xlim(1, 1000)

How to clear out session on log out

I use following to clear session and clear aspnet_sessionID:

HttpContext.Current.Session.Clear();
HttpContext.Current.Session.Abandon();
HttpContext.Current.Response.Cookies.Add(new HttpCookie("ASP.NET_SessionId", ""));

Skip first line(field) in loop using CSV file?

Probably you want something like:

firstline = True
for row in kidfile:
    if firstline:    #skip first line
        firstline = False
        continue
    # parse the line

An other way to achive the same result is calling readline before the loop:

kidfile.readline()   # skip the first line
for row in kidfile:
    #parse the line

source of historical stock data

For survivorship bias free data, the only reliable source I have found is QuantQuote (http://quantquote.com)

Data comes in minute, second, or tick resolution, link to their historical stock data.

There was a suggestion for kibot above. I would do a quick google search before buying from them, you'll find lots posts like this with warnings about kibot data quality problems. It is also telling that their supposedly survivorship bias free sp500 only has 570 symbols for 14 years. That's pretty much impossible, sp500 changes by 1-2 symbols per month....

In jQuery, what's the best way of formatting a number to 2 decimal places?

Maybe something like this, where you could select more than one element if you'd like?

$("#number").each(function(){
    $(this).val(parseFloat($(this).val()).toFixed(2));
});

R * not meaningful for factors ERROR

new[,2] is a factor, not a numeric vector. Transform it first

new$MY_NEW_COLUMN <-as.numeric(as.character(new[,2])) * 5

How to set the LDFLAGS in CMakeLists.txt?

If you want to add a flag to every link, e.g. -fsanitize=address then I would not recommend using CMAKE_*_LINKER_FLAGS. Even with them all set it still doesn't use the flag when linking a framework on OSX, and maybe in other situations. Instead use link_libraries():

add_compile_options("-fsanitize=address")
link_libraries("-fsanitize=address")

This works for everything.

HTML Script tag: type or language (or omit both)?

The type attribute is used to define the MIME type within the HTML document. Depending on what DOCTYPE you use, the type value is required in order to validate the HTML document.

The language attribute lets the browser know what language you are using (Javascript vs. VBScript) but is not necessarily essential and, IIRC, has been deprecated.

White spaces are required between publicId and systemId

The error message is actually correct if not obvious. It says that your DOCTYPE must have a SYSTEM identifier. I assume yours only has a public identifier.

You'll get the error with (for instance):

<!DOCTYPE persistence PUBLIC
    "http://java.sun.com/xml/ns/persistence/persistence_1_0.xsd">

You won't with:

<!DOCTYPE persistence PUBLIC
    "http://java.sun.com/xml/ns/persistence/persistence_1_0.xsd" "">

Notice "" at the end in the second one -- that's the system identifier. The error message is confusing: it should say that you need a system identifier, not that you need a space between the publicId and the (non-existent) systemId.

By the way, an empty system identifier might not be ideal, but it might be enough to get you moving.

Converting pfx to pem using openssl

Despite that the other answers are correct and thoroughly explained, I found some difficulties understanding them. Here is the method I used (Taken from here):

First case: To convert a PFX file to a PEM file that contains both the certificate and private key:

openssl pkcs12 -in filename.pfx -out cert.pem -nodes

Second case: To convert a PFX file to separate public and private key PEM files:

Extracts the private key form a PFX to a PEM file:

openssl pkcs12 -in filename.pfx -nocerts -out key.pem

Exports the certificate (includes the public key only):

openssl pkcs12 -in filename.pfx -clcerts -nokeys -out cert.pem

Removes the password (paraphrase) from the extracted private key (optional):

openssl rsa -in key.pem -out server.key

Simple post to Web Api

It's been quite sometime since I asked this question. Now I understand it more clearly, I'm going to put a more complete answer to help others.

In Web API, it's very simple to remember how parameter binding is happening.

  • if you POST simple types, Web API tries to bind it from the URL
  • if you POST complex type, Web API tries to bind it from the body of the request (this uses a media-type formatter).

  • If you want to bind a complex type from the URL, you'll use [FromUri] in your action parameter. The limitation of this is down to how long your data going to be and if it exceeds the url character limit.

    public IHttpActionResult Put([FromUri] ViewModel data) { ... }

  • If you want to bind a simple type from the request body, you'll use [FromBody] in your action parameter.

    public IHttpActionResult Put([FromBody] string name) { ... }

as a side note, say you are making a PUT request (just a string) to update something. If you decide not to append it to the URL and pass as a complex type with just one property in the model, then the data parameter in jQuery ajax will look something like below. The object you pass to data parameter has only one property with empty property name.

var myName = 'ABC';
$.ajax({url:.., data: {'': myName}});

and your web api action will look something like below.

public IHttpActionResult Put([FromBody] string name){ ... }

This asp.net page explains it all. http://www.asp.net/web-api/overview/formats-and-model-binding/parameter-binding-in-aspnet-web-api

Spring Security exclude url patterns in security annotation configurartion

Where are you configuring your authenticated URL pattern(s)? I only see one uri in your code.

Do you have multiple configure(HttpSecurity) methods or just one? It looks like you need all your URIs in the one method.

I have a site which requires authentication to access everything so I want to protect /*. However in order to authenticate I obviously want to not protect /login. I also have static assets I'd like to allow access to (so I can make the login page pretty) and a healthcheck page that shouldn't require auth.

In addition I have a resource, /admin, which requires higher privledges than the rest of the site.

The following is working for me.

@Override
protected void configure(HttpSecurity http) throws Exception {

    http.authorizeRequests()
        .antMatchers("/login**").permitAll()
        .antMatchers("/healthcheck**").permitAll()
        .antMatchers("/static/**").permitAll()
        .antMatchers("/admin/**").access("hasRole('ROLE_ADMIN')")
        .antMatchers("/**").access("hasRole('ROLE_USER')")
        .and()
            .formLogin().loginPage("/login").failureUrl("/login?error")
                .usernameParameter("username").passwordParameter("password")
        .and()
            .logout().logoutSuccessUrl("/login?logout")
        .and()
            .exceptionHandling().accessDeniedPage("/403")
        .and()
            .csrf();

}

NOTE: This is a first match wins so you may need to play with the order. For example, I originally had /** first:

        .antMatchers("/**").access("hasRole('ROLE_USER')")
        .antMatchers("/login**").permitAll()
        .antMatchers("/healthcheck**").permitAll()

Which caused the site to continually redirect all requests for /login back to /login. Likewise I had /admin/** last:

        .antMatchers("/**").access("hasRole('ROLE_USER')")
        .antMatchers("/admin/**").access("hasRole('ROLE_ADMIN')")

Which resulted in my unprivledged test user "guest" having access to the admin interface (yikes!)

C#: Assign same value to multiple variables in single statement

int num1, num2, num3;

num1 = num2 = num3 = 5;

Console.WriteLine(num1 + "=" + num2 + "=" + num3);    // 5=5=5

While variable is not defined - wait

You can use this:

var refreshIntervalId = null;
refreshIntervalId = setInterval(checkIfVariableIsSet, 1000);

var checkIfVariableIsSet = function()
{
    if(typeof someVariable !== 'undefined'){
        $('a.play').trigger("click");
        clearInterval(refreshIntervalId);
    }
};

Bootstrap 3 modal responsive

From the docs:

Modals have two optional sizes, available via modifier classes to be placed on a .modal-dialog: modal-lg and modal-sm (as of 3.1).

Also the modal dialogue will scale itself on small screens (as of 3.1.1).

Parsing GET request parameters in a URL that contains another URL

if (isset($_SERVER['HTTPS'])){
    echo "https://$_SERVER[HTTP_HOST]$_SERVER[REQUEST_URI]$_SERVER[QUERY_STRING]";
}else{
    echo "http://$_SERVER[HTTP_HOST]$_SERVER[REQUEST_URI]$_SERVER[QUERY_STRING]";
}

Set order of columns in pandas dataframe

Add the 'columns' parameter:

frame = pd.DataFrame({
        'one thing':[1,2,3,4],
        'second thing':[0.1,0.2,1,2],
        'other thing':['a','e','i','o']},
        columns=['one thing', 'second thing', 'other thing']
)

Undefined behavior and sequence points

This is a follow up to my previous answer and contains C++11 related material..


Pre-requisites : An elementary knowledge of Relations (Mathematics).


Is it true that there are no Sequence Points in C++11?

Yes! This is very true.

Sequence Points have been replaced by Sequenced Before and Sequenced After (and Unsequenced and Indeterminately Sequenced) relations in C++11.


What exactly is this 'Sequenced before' thing?

Sequenced Before(§1.9/13) is a relation which is:

between evaluations executed by a single thread and induces a strict partial order1

Formally it means given any two evaluations(See below) A and B, if A is sequenced before B, then the execution of A shall precede the execution of B. If A is not sequenced before B and B is not sequenced before A, then A and B are unsequenced 2.

Evaluations A and B are indeterminately sequenced when either A is sequenced before B or B is sequenced before A, but it is unspecified which3.

[NOTES]
1 : A strict partial order is a binary relation "<" over a set P which is asymmetric, and transitive, i.e., for all a, b, and c in P, we have that:
........(i). if a < b then ¬ (b < a) (asymmetry);
........(ii). if a < b and b < c then a < c (transitivity).
2 : The execution of unsequenced evaluations can overlap.
3 : Indeterminately sequenced evaluations cannot overlap, but either could be executed first.


What is the meaning of the word 'evaluation' in context of C++11?

In C++11, evaluation of an expression (or a sub-expression) in general includes:

  • value computations (including determining the identity of an object for glvalue evaluation and fetching a value previously assigned to an object for prvalue evaluation) and

  • initiation of side effects.

Now (§1.9/14) says:

Every value computation and side effect associated with a full-expression is sequenced before every value computation and side effect associated with the next full-expression to be evaluated.

  • Trivial example:

    int x; x = 10; ++x;

    Value computation and side effect associated with ++x is sequenced after the value computation and side effect of x = 10;


So there must be some relation between Undefined Behaviour and the above-mentioned things, right?

Yes! Right.

In (§1.9/15) it has been mentioned that

Except where noted, evaluations of operands of individual operators and of subexpressions of individual expressions are unsequenced4.

For example :

int main()
{
     int num = 19 ;
     num = (num << 3) + (num >> 3);
} 
  1. Evaluation of operands of + operator are unsequenced relative to each other.
  2. Evaluation of operands of << and >> operators are unsequenced relative to each other.

4: In an expression that is evaluated more than once during the execution of a program, unsequenced and indeterminately sequenced evaluations of its subexpressions need not be performed consistently in different evaluations.

(§1.9/15) The value computations of the operands of an operator are sequenced before the value computation of the result of the operator.

That means in x + y the value computation of x and y are sequenced before the value computation of (x + y).

More importantly

(§1.9/15) If a side effect on a scalar object is unsequenced relative to either

(a) another side effect on the same scalar object

or

(b) a value computation using the value of the same scalar object.

the behaviour is undefined.

Examples:

int i = 5, v[10] = { };
void  f(int,  int);
  1. i = i++ * ++i; // Undefined Behaviour
  2. i = ++i + i++; // Undefined Behaviour
  3. i = ++i + ++i; // Undefined Behaviour
  4. i = v[i++]; // Undefined Behaviour
  5. i = v[++i]: // Well-defined Behavior
  6. i = i++ + 1; // Undefined Behaviour
  7. i = ++i + 1; // Well-defined Behaviour
  8. ++++i; // Well-defined Behaviour
  9. f(i = -1, i = -1); // Undefined Behaviour (see below)

When calling a function (whether or not the function is inline), every value computation and side effect associated with any argument expression, or with the postfix expression designating the called function, is sequenced before execution of every expression or statement in the body of the called function. [Note: Value computations and side effects associated with different argument expressions are unsequenced. — end note]

Expressions (5), (7) and (8) do not invoke undefined behaviour. Check out the following answers for a more detailed explanation.


Final Note :

If you find any flaw in the post please leave a comment. Power-users (With rep >20000) please do not hesitate to edit the post for correcting typos and other mistakes.

Regular expression include and exclude special characters

You haven't actually asked a question, but assuming you have one, this could be your answer...

Assuming all characters, except the "Special Characters" are allowed you can write

String regex = "^[^<>'\"/;`%]*$";

How to change status bar color in Flutter?

to Make it Like your App Bar Color

import 'package:flutter/material.dart';

 Widget build(BuildContext context) {
  SystemChrome.setSystemUIOverlayStyle(SystemUiOverlayStyle(
      statusBarColor: Colors.transparent,
      systemNavigationBarColor: Colors.transparent,
  ));
 }

How to disable text selection highlighting

I have learned from the CSS-Tricks website.

user-select: none;

And this also:

::selection {
    background-color: transparent;
}

::moz-selection {
    background-color: transparent;
}

::webkit-selection {
    background-color: transparent;
}

Loading .sql files from within PHP

    $sql = file_get_contents("sql.sql");

Seems to be the simplest answer

what is the use of xsi:schemaLocation?

If you go into any of those locations, then you will find what is defined in those schema. For example, it tells you what is the data type of the ini-method key words value.

CSS position:fixed inside a positioned element

I know this is an old post but I had the same question but didn't find an answer that set the element fixed relative to a parent div. The scroll bar on medium.com is a great pure CSS solution for setting something position: fixed; relative to a parent element instead of the viewport (kinda*). It is achieved by setting the parent div to position: relative; and having a button wrapper with position: absolute; and the button of course is position: fixed; as follows:

<div class="wrapper">
  <div class="content">
    Your long content here
  </div>

  <div class="button-wrapper">
    <button class="button">This is your button</button>
  </div>
</div>

<style>
  .wrapper {
    position: relative;
  }

  .button-wrapper {
    position: absolute;
    right: 0;
    top: 0;
    width: 50px;
  }

  .button {
    position: fixed;
    top: 0;
    width: 50px;
  }
</style>

working example

*Since fixed elements don't scroll with the page the vertical position will still be relative to the viewport but the horizontal position is relative to the parent with this solution.

How can I convert a Timestamp into either Date or DateTime object?

import java.sql.Timestamp;
import java.text.SimpleDateFormat;
import java.util.Date;

public class DateTest {

    public static void main(String[] args) {
        Timestamp timestamp = new Timestamp(System.currentTimeMillis());
        Date date = new Date(timestamp.getTime());

        // S is the millisecond
        SimpleDateFormat simpleDateFormat = new SimpleDateFormat("MM/dd/yyyy' 'HH:mm:ss:S");

        System.out.println(simpleDateFormat.format(timestamp));
        System.out.println(simpleDateFormat.format(date));
    }
}

internal/modules/cjs/loader.js:582 throw err

same happen to me i just resolved by deleting "dist" file and re run the app.

System.Security.SecurityException when writing to Event Log

I ran into the same issue, but I had to go up one level and give full access to everyone to the HKEY_LOCAL_MACHINE\SYSTEM\CurrentControlSet\Services\EventLog\ key, instead of going down to security, that cleared up the issue for me.

Get img src with PHP

I know people say you shouldn't use regular expressions to parse HTML, but in this case I find it perfectly fine.

$string = '<img border="0" src="/images/image.jpg" alt="Image" width="100" height="100" />';
preg_match('/<img(.*)src(.*)=(.*)"(.*)"/U', $string, $result);
$foo = array_pop($result);

Pad a number with leading zeros in JavaScript

Not a lot of "slick" going on so far:

function pad(n, width, z) {
  z = z || '0';
  n = n + '';
  return n.length >= width ? n : new Array(width - n.length + 1).join(z) + n;
}

When you initialize an array with a number, it creates an array with the length set to that value so that the array appears to contain that many undefined elements. Though some Array instance methods skip array elements without values, .join() doesn't, or at least not completely; it treats them as if their value is the empty string. Thus you get a copy of the zero character (or whatever "z" is) between each of the array elements; that's why there's a + 1 in there.

Example usage:

pad(10, 4);      // 0010
pad(9, 4);       // 0009
pad(123, 4);     // 0123

pad(10, 4, '-'); // --10

PHP sessions that have already been started

try this

if(!isset($_SESSION)){ 
    session_start();
}

I suggest you to use ob_start(); before starting any sesson varriable, this should order you browser buffer.

edit: Added an extra ) after $_SESSION

How can I overwrite file contents with new content in PHP?

Use file_put_contents()

file_put_contents('file.txt', 'bar');
echo file_get_contents('file.txt'); // bar
file_put_contents('file.txt', 'foo');
echo file_get_contents('file.txt'); // foo

Alternatively, if you're stuck with fopen() you can use the w or w+ modes:

'w' Open for writing only; place the file pointer at the beginning of the file and truncate the file to zero length. If the file does not exist, attempt to create it.

'w+' Open for reading and writing; place the file pointer at the beginning of the file and truncate the file to zero length. If the file does not exist, attempt to create it.

Android design support library for API 28 (P) not working

Design support library for androidX is implementation 'com.google.android.material:material:1.0.0'

How to use color picker (eye dropper)?

To open the Eye Dropper simply:

  1. Open DevTools F12
  2. Go to Elements tab
  3. Under Styles side bar click on any color preview box

enter image description here

Its main functionality is to inspect pixel color values by clicking them though with its new features you can also see your page's existing colors palette or material design palette by clicking on the two arrows icon at the bottom. It can get quite handy when designing your page.

How do I make a transparent border with CSS?

Since you said in a comment that the more options you have, the better, here's another one.

In CSS3, there are two different so-called "box models". One adds the border and padding to the width of a block element, while the other does not. You can use the latter by specifying

-webkit-box-sizing: border-box;
-moz-box-sizing: border-box;
-ms-box-sizing: border-box;
box-sizing: border-box;

Then, in modern browsers, the element will always have the same width. I.e., if you apply a border to it on hover, the width of the border will not add to the overall width of the element; the border will be added "inside" the element, so to speak. However, if I remember correctly, you must specify the width explicitly for this to work. Which is probably not an option for you in this particular case, but you can keep it in mind for future situations.

Python 3 turn range to a list

Use Range in Python 3.

Here is a example function that return in between numbers from two numbers

def get_between_numbers(a, b):
    """
    This function will return in between numbers from two numbers.
    :param a:
    :param b:
    :return:
    """
    x = []
    if b < a:
        x.extend(range(b, a))
        x.append(a)
    else:
        x.extend(range(a, b))
        x.append(b)

    return x

Result

print(get_between_numbers(5, 9))
print(get_between_numbers(9, 5))

[5, 6, 7, 8, 9]  
[5, 6, 7, 8, 9]

VBA Excel 2-Dimensional Arrays

You need ReDim:

m = 5
n = 8
Dim my_array()
ReDim my_array(1 To m, 1 To n)
For i = 1 To m
  For j = 1 To n
    my_array(i, j) = i * j
  Next
Next

For i = 1 To m
  For j = 1 To n
    Cells(i, j) = my_array(i, j)
  Next
Next

As others have pointed out, your actual problem would be better solved with ranges. You could try something like this:

Dim r1 As Range
Dim r2 As Range
Dim ws1 As Worksheet
Dim ws2 As Worksheet

Set ws1 = Worksheets("Sheet1")
Set ws2 = Worksheets("Sheet2")
totalRow = ws1.Range("A1").End(xlDown).Row
totalCol = ws1.Range("A1").End(xlToRight).Column

Set r1 = ws1.Range(ws1.Cells(1, 1), ws1.Cells(totalRow, totalCol))
Set r2 = ws2.Range(ws2.Cells(1, 1), ws2.Cells(totalRow, totalCol))
r2.Value = r1.Value

SQL Query to find missing rows between two related tables

SELECT A.ABC_ID, A.VAL FROM A WHERE NOT EXISTS 
   (SELECT * FROM B WHERE B.ABC_ID = A.ABC_ID AND B.VAL = A.VAL)

or

SELECT A.ABC_ID, A.VAL FROM A WHERE VAL NOT IN 
    (SELECT VAL FROM B WHERE B.ABC_ID = A.ABC_ID)

or

SELECT A.ABC_ID, A.VAL LEFT OUTER JOIN B 
    ON A.ABC_ID = B.ABC_ID AND A.VAL = B.VAL FROM A WHERE B.VAL IS NULL

Please note that these queries do not require that ABC_ID be in table B at all. I think that does what you want.

Webfont Smoothing and Antialiasing in Firefox and Opera

I found the solution with this link : http://pixelsvsbytes.com/blog/2013/02/nice-web-fonts-for-every-browser/

Step by step method :

  • send your font to a WebFontGenerator and get the zip
  • find the TTF font on the Zip file
  • then, on linux, do this command (or install by apt-get install ttfautohint):
    ttfautohint --strong-stem-width=g neosansstd-black.ttf neosansstd-black.changed.ttf
  • then, one more, send the new TTF file (neosansstd-black.changed.ttf) on the WebFontGenerator
  • you get a perfect Zip with all your webfonts !

I hope this will help.

Add a thousands separator to a total with Javascript or jQuery?

I know this is an uber old post and has good answers, BUT if anyone is interested, there is a jQuery plugin which simplifies number formatting (thousands formatting, number of decimal places, custom thousands separator, etc) by making an include and a simple call. Has lots of features and documentation is enough. It's called jQuery Number.

You just include it:

<script type="text/javascript" src="jquery/jquery.number.min.js"></script>

And then use it:

On an automatic formatting HTML input: $('input.number').number( true, 2 );

or

On a JS call: $.number( 5020.2364, 2 ); // Outputs: 5,020.24

Hopefully this helps someone.

"replace" function examples

Here's two simple examples

> x <- letters[1:4]
> replace(x, 3, 'Z') #replacing 'c' by 'Z'
[1] "a" "b" "Z" "d"
> 
> y <- 1:10
> replace(y, c(4,5), c(20,30)) # replacing 4th and 5th elements by 20 and 30
 [1]  1  2  3 20 30  6  7  8  9 10

ORA-12154 could not resolve the connect identifier specified

Had a similar issue, only my web app was fine and it was SQLPlus that was giving me issues connecting, and the ORA-12154 could not resolve the connect identifier specified error. I had 11g and 12 Oracle clients installed. My environment variables were all set to point at my 12 instance:

  • ORACLE_HOME = C:\oracle\product\12
  • PATH = C:\oracle\product\12\bin;....
  • TNS_ADMIN = C:\oracle\product\12\network\admin

There is also a registry entry required at HKLM\Software\Oracle\KEY_OraClient12Home1, a string entry of TNS_ADMIN with the same path as the environment variable.

I have a tnsnames.ora at both C:\oracle\product\11\network\admin and C:\oracle\product\12\network\admin. As far as I know, both my web app and the 12 SQLPlus client I was using should have been using all 12 version variables.

My troubleshooting steps:

  • Change all environmental variables above from 12 to 11.
  • Connect with 11g's SQLPlus (worked!)
  • Change all environmental variables above back from 11 to 12.
  • Connect with 12's SQLPlus again (worked!)

So I don't really know what caused 12's SQLPlus to stop connecting, but this kind of reset may work for someone, so thought I'd document it here.

How to see PL/SQL Stored Function body in Oracle

If is a package then you can get the source for that with:

    select text from all_source where name = 'PADCAMPAIGN' 
    and type = 'PACKAGE BODY'
    order by line;

Oracle doesn't store the source for a sub-program separately, so you need to look through the package source for it.

Note: I've assumed you didn't use double-quotes when creating that package, but if you did , then use

    select text from all_source where name = 'pAdCampaign' 
    and type = 'PACKAGE BODY'
    order by line;

Select element by exact match of its content

Like T.J. Crowder stated above, the filter function does wonders. It wasn't working for me in my specific case. I needed to search multiple tables and their respective td tags inside a div (in this case a jQuery dialog).

$("#MyJqueryDialog table tr td").filter(function () {
    // The following implies that there is some text inside the td tag.
    if ($.trim($(this).text()) == "Hello World!") {
       // Perform specific task.
    }
});

I hope this is helpful to someone!

How do I use a compound drawable instead of a LinearLayout that contains an ImageView and a TextView

TextView comes with 4 compound drawables, one for each of left, top, right and bottom.

In your case, you do not need the LinearLayout and ImageView at all. Just add android:drawableLeft="@drawable/up_count_big" to your TextView.

See TextView#setCompoundDrawablesWithIntrinsicBounds for more info.

How to prevent XSS with HTML/PHP?

In order of preference:

  1. If you are using a templating engine (e.g. Twig, Smarty, Blade), check that it offers context-sensitive escaping. I know from experience that Twig does. {{ var|e('html_attr') }}
  2. If you want to allow HTML, use HTML Purifier. Even if you think you only accept Markdown or ReStructuredText, you still want to purify the HTML these markup languages output.
  3. Otherwise, use htmlentities($var, ENT_QUOTES | ENT_HTML5, $charset) and make sure the rest of your document uses the same character set as $charset. In most cases, 'UTF-8' is the desired character set.

Also, make sure you escape on output, not on input.

Parsing ISO 8601 date in Javascript

datejs could parse following, you might want to try out.

Date.parse('1997-07-16T19:20:15')           // ISO 8601 Formats
Date.parse('1997-07-16T19:20:30+01:00')     // ISO 8601 with Timezone offset

Edit: Regex version

x = "2011-01-28T19:30:00EST"

MM = ["January", "February","March","April","May","June","July","August","September","October","November", "December"]

xx = x.replace(
    /(\d{4})-(\d{2})-(\d{2})T(\d{2}):(\d{2}):\d{2}(\w{3})/,
    function($0,$1,$2,$3,$4,$5,$6){
        return MM[$2-1]+" "+$3+", "+$1+" - "+$4%12+":"+$5+(+$4>12?"PM":"AM")+" "+$6
    }
)

Result

January 28, 2011 - 7:30PM EST

Edit2: I changed my timezone to EST and now I got following

x = "2011-01-28T19:30:00-05:00"

MM = {Jan:"January", Feb:"February", Mar:"March", Apr:"April", May:"May", Jun:"June", Jul:"July", Aug:"August", Sep:"September", Oct:"October", Nov:"November", Dec:"December"}

xx = String(new Date(x)).replace(
    /\w{3} (\w{3}) (\d{2}) (\d{4}) (\d{2}):(\d{2}):[^(]+\(([A-Z]{3})\)/,
    function($0,$1,$2,$3,$4,$5,$6){
        return MM[$1]+" "+$2+", "+$3+" - "+$4%12+":"+$5+(+$4>12?"PM":"AM")+" "+$6 
    }
)

return

January 28, 2011 - 7:30PM EST

Basically

String(new Date(x))

return

Fri Jan 28 2011 19:30:00 GMT-0500 (EST)

regex parts just converting above string to your required format.

January 28, 2011 - 7:30PM EST

writing to existing workbook using xlwt

Here's some sample code I used recently to do just that.

It opens a workbook, goes down the rows, if a condition is met it writes some data in the row. Finally it saves the modified file.

from xlutils.copy import copy # http://pypi.python.org/pypi/xlutils
from xlrd import open_workbook # http://pypi.python.org/pypi/xlrd

START_ROW = 297 # 0 based (subtract 1 from excel row number)
col_age_november = 1
col_summer1 = 2
col_fall1 = 3

rb = open_workbook(file_path,formatting_info=True)
r_sheet = rb.sheet_by_index(0) # read only copy to introspect the file
wb = copy(rb) # a writable copy (I can't read values out of this, only write to it)
w_sheet = wb.get_sheet(0) # the sheet to write to within the writable copy

for row_index in range(START_ROW, r_sheet.nrows):
    age_nov = r_sheet.cell(row_index, col_age_november).value
    if age_nov == 3:
        #If 3, then Combo I 3-4 year old  for both summer1 and fall1
        w_sheet.write(row_index, col_summer1, 'Combo I 3-4 year old')
        w_sheet.write(row_index, col_fall1, 'Combo I 3-4 year old')

wb.save(file_path + '.out' + os.path.splitext(file_path)[-1])

Sorting an IList in C#

Found a good post on this and thought I'd share. Check it out HERE

Basically.

You can create the following class and IComparer Classes

public class Widget {
    public string Name = string.Empty;
    public int Size = 0;

    public Widget(string name, int size) {
    this.Name = name;
    this.Size = size;
}
}

public class WidgetNameSorter : IComparer<Widget> {
    public int Compare(Widget x, Widget y) {
        return x.Name.CompareTo(y.Name);
}
}

public class WidgetSizeSorter : IComparer<Widget> {
    public int Compare(Widget x, Widget y) {
    return x.Size.CompareTo(y.Size);
}
}

Then If you have an IList, you can sort it like this.

List<Widget> widgets = new List<Widget>();
widgets.Add(new Widget("Zeta", 6));
widgets.Add(new Widget("Beta", 3));
widgets.Add(new Widget("Alpha", 9));

widgets.Sort(new WidgetNameSorter());
widgets.Sort(new WidgetSizeSorter());

But Checkout this site for more information... Check it out HERE

How to retrieve a single file from a specific revision in Git?

Get the file from a previous commit through checking-out previous commit and copying file.

  • Note which branch you are on: git branch
  • Checkout the previous commit you want: git checkout 27cf8e84bb88e24ae4b4b3df2b77aab91a3735d8
  • Copy the file you want to a temporary location
  • Checkout the branch you started from: git checkout theBranchYouNoted
  • Copy in the file you placed in a temporary location
  • Commit your change to git: git commit -m "added file ?? from previous commit"

How do I use hexadecimal color strings in Flutter?

if you want to use hex code of color which is in this format #123456 then it is very easily be used, create A variables of type Color and assign the following values to it.

Color myHexColor = Color(0xff123456) 

// her you notice I use the 0xff and that is opacity or transparency of the color 
// and you can also change these value .

use myhexcolor and you are ready to go .

if you want to change the opacity of color direct from the hex code then change the ff value in 0xff to the respectively value from the table below.

Hex Opacity Values

100% — FF

95% — F2

90% — E6

85% — D9

80% — CC

75% — BF

70% — B3

65% — A6

60% — 99

55% — 8C

50% — 80

45% — 73

40% — 66

35% — 59

30% — 4D

25% — 40

20% — 33

15% — 26

10% — 1A

5% — 0D

0% — 00

Deleting a local branch with Git

Switch to some other branch and delete Test_Branch, as follows:

$ git checkout master
$ git branch -d Test_Branch

If above command gives you error - The branch 'Test_Branch' is not fully merged. If you are sure you want to delete it and still you want to delete it, then you can force delete it using -D instead of -d, as:

$ git branch -D Test_Branch

To delete Test_Branch from remote as well, execute:

git push origin --delete Test_Branch

Loading an image to a <img> from <input file>

In browsers supporting the File API, you can use the FileReader constructor to read files once they have been selected by the user.

Example

document.getElementById('picField').onchange = function (evt) {
    var tgt = evt.target || window.event.srcElement,
        files = tgt.files;

    // FileReader support
    if (FileReader && files && files.length) {
        var fr = new FileReader();
        fr.onload = function () {
            document.getElementById(outImage).src = fr.result;
        }
        fr.readAsDataURL(files[0]);
    }

    // Not supported
    else {
        // fallback -- perhaps submit the input to an iframe and temporarily store
        // them on the server until the user's session ends.
    }
}

Browser support

  • IE 10
  • Safari 6.0.2
  • Chrome 7
  • Firefox 3.6
  • Opera 12.02

Where the File API is unsupported, you cannot (in most security conscious browsers) get the full path of a file from a file input box, nor can you access the data. The only viable solution would be to submit the form to a hidden iframe and have the file pre-uploaded to the server. Then, when that request completes you could set the src of the image to the location of the uploaded file.

Live video streaming using Java?

The best video playback/encoding library I have ever seen is ffmpeg. It plays everything you throw at it. (It is used by MPlayer.) It is written in C but I found some Java wrappers.

  • FFMPEG-Java: A Java wrapper around ffmpeg using JNA.
  • jffmpeg: This one integrates to JMF.

how to make label visible/invisible?

You can set display attribute as none to hide a label.

<label id="excel-data-div" style="display: none;"></label>

How to create helper file full of functions in react native?

Quick note: You are importing a class, you can't call properties on a class unless they are static properties. Read more about classes here: https://developer.mozilla.org/en-US/docs/Web/JavaScript/Reference/Classes

There's an easy way to do this, though. If you are making helper functions, you should instead make a file that exports functions like this:

export function HelloChandu() {

}

export function HelloTester() {

}

Then import them like so:

import { HelloChandu } from './helpers'

or...

import functions from './helpers' then functions.HelloChandu

Rails - How to use a Helper Inside a Controller

class MyController < ApplicationController
    # include your helper
    include MyHelper
    # or Rails helper
    include ActionView::Helpers::NumberHelper

    def my_action
      price = number_to_currency(10000)
    end
end

In Rails 5+ simply use helpers (helpers.number_to_currency(10000))

Action Bar's onClick listener for the Home button

Best way to customize Action bar onClickListener is onSupportNavigateUp()

This code will be helpful link for helping code

Convert dateTime to ISO format yyyy-mm-dd hh:mm:ss in C#

There is no standard format for the readable 8601 format. You can use a custom format:

theDate.ToString("yyyy-MM-dd HH':'mm':'ss")

(The standard format "s" will give you a "T" between the date and the time, not a space.)

Is there an Eclipse plugin to run system shell in the Console?

You don't need a plugin (including the Remote System View plugin), you can do this with the basic platform. You just create an external tool configuration. I've added an image to demonstrate.

screenshot from Mac of external tools configuration dialog with colored arrows

Orange Arrows: Use the external tool button on the toolbar and select External Tools Configuration.... Click on Program then up above click on the New launch configuration icon.

Green Arrows: Use the Name field and name your new tool something clever like "Launch Shell". In the Location area enter a shell command e.g. /bin/bash. A more generic approach would be to use ${env_var:SHELL} which under the Mac (and I hope Linux) launches the default shell. Then in the Working Directory you can use the variable ${project_loc} to set the default directory to your current project location. This will mean that when you launch the tool, you have to make sure you have your cursor in an active project on the explorer or in an appropriate editor window. Under the Arguments area use -i for interactive mode.

Blue arrows: Switch to the Build tab and uncheck Build before launch. Then switch to the Common tab and click to add your command to the favorites menu. Now click Apply and Close. Make sure the console view is showing (Window->Show View->Console). Click on a project in the Package or Project Explorer or click in an editor window that has code for a project of interest. Then click on the external tool icon and select Launch Shell, you now have an interactive shell window in the console view.

In the lower left of the image you can see the tcsh shell in action.

Windows Note: This also works in Windows but you use ${env_var:ComSpec} in the location field and you can leave the arguments field blank.

Cannot enqueue Handshake after invoking quit

I think this issue is similar to mine:

  1. Connect to MySQL
  2. End MySQL service (should not quit node script)
  3. Start MySQL service, Node reconnects to MySQL
  4. Query the DB -> FAIL (Cannot enqueue Query after fatal error.)

I solved this issue by recreating a new connection with the use of promises (q).

mysql-con.js

'use strict';
var config          = require('./../config.js');
var colors          = require('colors');
var mysql           = require('mysql');
var q               = require('q');
var MySQLConnection = {};

MySQLConnection.connect = function(){
    var d = q.defer();
    MySQLConnection.connection = mysql.createConnection({
        host                : 'localhost',
        user                : 'root',
        password            : 'password',
        database            : 'database'
    });

    MySQLConnection.connection.connect(function (err) {
        if(err) {
            console.log('Not connected '.red, err.toString().red, ' RETRYING...'.blue);
            d.reject();
        } else {
            console.log('Connected to Mysql. Exporting..'.blue);
            d.resolve(MySQLConnection.connection);
        }
    });
    return d.promise;
};

module.exports = MySQLConnection;

mysqlAPI.js

var colors          = require('colors');
var mysqlCon        = require('./mysql-con.js');
mysqlCon.connect().then(function(con){
   console.log('connected!');
    mysql = con;
    mysql.on('error', function (err, result) {
        console.log('error occurred. Reconneting...'.purple);
        mysqlAPI.reconnect();
    });
    mysql.query('SELECT 1 + 1 AS solution', function (err, results) {
            if(err) console.log('err',err);
            console.log('Works bro ',results);
    });
});

mysqlAPI.reconnect = function(){
    mysqlCon.connect().then(function(con){
      console.log("connected. getting new reference");
        mysql = con;
        mysql.on('error', function (err, result) {
            mysqlAPI.reconnect();
        });
    }, function (error) {
      console.log("try again");
        setTimeout(mysqlAPI.reconnect, 2000);
    });
};

I hope this helps.

Fastest way of finding differences between two files in unix?

This will work fast:

Case 1 - File2 = File1 + extra text appended.

grep -Fxvf File2.txt File1.txt >> File3.txt

File 1: 80 Lines File 2: 100 Lines File 3: 20 Lines

Find a line in a file and remove it

Here is the complete Class. In the below file "somelocation" refers to the actual path of the file.

import java.io.BufferedReader;
import java.io.BufferedWriter;
import java.io.File;
import java.io.FileReader;
import java.io.FileWriter;
import java.io.IOException;



public class FileProcess
{


    public static void main(String[] args) throws IOException
    {
        File inputFile = new File("C://somelocation//Demographics.txt");
        File tempFile = new File("C://somelocation//Demographics_report.txt");

        BufferedReader reader = new BufferedReader(new FileReader(inputFile));
        BufferedWriter writer = new BufferedWriter(new FileWriter(tempFile));

        String currentLine;

        while((currentLine = reader.readLine()) != null) {
            if(null!=currentLine && !currentLine.equalsIgnoreCase("BBB")){
                writer.write(currentLine + System.getProperty("line.separator"));
            }
        }
        writer.close(); 
        reader.close(); 
        boolean successful = tempFile.renameTo(inputFile);
        System.out.println(successful);
    }

}

Why doesn't Git ignore my specified file?

Make sure that your .gitignore is in the root of the working directory, and in that directory run git status and copy the path to the file from the status output and paste it into the .gitignore.

If that doesn’t work, then it’s likely that your file is already tracked by Git. You can confirm this through the output of git status. If the file is not listed in the “Untracked files” section, then it is already tracked by Git and it will ignore the rule from the .gitignore file.

The reason to ignore files in Git is so that they won't be added to the repository. If you previously added a file you want to be ignored, then it will be tracked by Git and the ignore rules matching it will be skipped. Git does this since the file is already part of the repository.

In order to actually ignore the file, you have to untrack it and remove it from the repository. You can do that by using git rm --cached sites/default/settings.php. This removes the file from the repository without physically deleting the file (that’s what the --cached does). After committing that change, the file will be removed from the repository, and ignoring it should work properly.

text box input height

You can define a class or id for input fields.

Or

input {
    line-height: 20px;
}

Hope this helps you.

How to find my php-fpm.sock?

Check the config file, the config path is /etc/php5/fpm/pool.d/www.conf, there you'll find the path by config and if you want you can change it.

EDIT:
well you're correct, you need to replace listen = 127.0.0.1:9000 to listen = /var/run/php5-fpm/php5-fpm.sock, then you need to run sudo service php5-fpm restart, and make sure it says that it restarted correctly, if not then make sure that /var/run/ has a folder called php5-fpm, or make it listen to /var/run/php5-fpm.sock cause i don't think the folder inside /var/run is created automatically, i remember i had to edit the start up script to create that folder, otherwise even if you mkdir /var/run/php5-fpm after restart that folder will disappear and the service starting will fail.

Insert variable values in the middle of a string

Use String.Format

Pre C# 6.0

string data = "FlightA, B,C,D";
var str = String.Format("Hi We have these flights for you: {0}. Which one do you want?", data);

C# 6.0 -- String Interpolation

string data = "FlightA, B,C,D";
var str = $"Hi We have these flights for you: {data}. Which one do you want?";

http://www.informit.com/articles/article.aspx?p=2422807

How to close form

new WindowSettings();

You just closed a brand new instance of the form that wasn't visible in the first place.

You need to close the original instance of the form by accepting it as a constructor parameter and storing it in a field.

Python check if list items are integers?

You can use exceptional handling as str.digit will only work for integers and can fail for something like this too:

>>> str.isdigit(' 1')
False

Using a generator function:

def solve(lis):                                        
    for x in lis:
        try:
            yield float(x)
        except ValueError:    
            pass

>>> mylist = ['1','orange','2','3','4','apple', '1.5', '2.6']
>>> list(solve(mylist))                                    
[1.0, 2.0, 3.0, 4.0, 1.5, 2.6]   #returns converted values

or may be you wanted this:

def solve(lis):
    for x in lis:
        try:
            float(x)
            return True
        except:
            return False
...         
>>> mylist = ['1','orange','2','3','4','apple', '1.5', '2.6']
>>> [x for x in mylist if solve(x)]
['1', '2', '3', '4', '1.5', '2.6']

or using ast.literal_eval, this will work for all types of numbers:

>>> from ast import literal_eval
>>> def solve(lis):
    for x in lis:
        try:
            literal_eval(x)
            return True
        except ValueError:   
             return False
...         
>>> mylist=['1','orange','2','3','4','apple', '1.5', '2.6', '1+0j']
>>> [x for x in mylist if solve(x)]                               
['1', '2', '3', '4', '1.5', '2.6', '1+0j']

Named colors in matplotlib

I constantly forget the names of the colors I want to use and keep coming back to this question =)

The previous answers are great, but I find it a bit difficult to get an overview of the available colors from the posted image. I prefer the colors to be grouped with similar colors, so I slightly tweaked the matplotlib answer that was mentioned in a comment above to get a color list sorted in columns. The order is not identical to how I would sort by eye, but I think it gives a good overview.

I updated the image and code to reflect that 'rebeccapurple' has been added and the three sage colors have been moved under the 'xkcd:' prefix since I posted this answer originally.

enter image description here

I really didn't change much from the matplotlib example, but here is the code for completeness.

import matplotlib.pyplot as plt
from matplotlib import colors as mcolors


colors = dict(mcolors.BASE_COLORS, **mcolors.CSS4_COLORS)

# Sort colors by hue, saturation, value and name.
by_hsv = sorted((tuple(mcolors.rgb_to_hsv(mcolors.to_rgba(color)[:3])), name)
                for name, color in colors.items())
sorted_names = [name for hsv, name in by_hsv]

n = len(sorted_names)
ncols = 4
nrows = n // ncols

fig, ax = plt.subplots(figsize=(12, 10))

# Get height and width
X, Y = fig.get_dpi() * fig.get_size_inches()
h = Y / (nrows + 1)
w = X / ncols

for i, name in enumerate(sorted_names):
    row = i % nrows
    col = i // nrows
    y = Y - (row * h) - h

    xi_line = w * (col + 0.05)
    xf_line = w * (col + 0.25)
    xi_text = w * (col + 0.3)

    ax.text(xi_text, y, name, fontsize=(h * 0.8),
            horizontalalignment='left',
            verticalalignment='center')

    ax.hlines(y + h * 0.1, xi_line, xf_line,
              color=colors[name], linewidth=(h * 0.8))

ax.set_xlim(0, X)
ax.set_ylim(0, Y)
ax.set_axis_off()

fig.subplots_adjust(left=0, right=1,
                    top=1, bottom=0,
                    hspace=0, wspace=0)
plt.show()

Additional named colors

Updated 2017-10-25. I merged my previous updates into this section.

xkcd

If you would like to use additional named colors when plotting with matplotlib, you can use the xkcd crowdsourced color names, via the 'xkcd:' prefix:

plt.plot([1,2], lw=4, c='xkcd:baby poop green')

Now you have access to a plethora of named colors!

enter image description here

Tableau

The default Tableau colors are available in matplotlib via the 'tab:' prefix:

plt.plot([1,2], lw=4, c='tab:green')

There are ten distinct colors:

enter image description here

HTML

You can also plot colors by their HTML hex code:

plt.plot([1,2], lw=4, c='#8f9805')

This is more similar to specifying and RGB tuple rather than a named color (apart from the fact that the hex code is passed as a string), and I will not include an image of the 16 million colors you can choose from...


For more details, please refer to the matplotlib colors documentation and the source file specifying the available colors, _color_data.py.


How to subtract hours from a date in Oracle so it affects the day also

sysdate-(2/11)

A day consists of 24 hours. So, to subtract 2 hours from a day you need to divide it by 24:

DATE_value - 2/24

Using interval for the same:

DATE_value - interval '2' hour

failed to find target with hash string 'android-22'

Okay you must try this guys it works for me:

  1. Open SDK Manager and Install SDK build tools 22.0.1
  2. Sync gradle That'all

Auto-expanding layout with Qt-Designer

Once you have add your layout with at least one widget in it, select your window and click the "Update" button of QtDesigner. The interface will be resized at the most optimized size and your layout will fit the whole window. Then when resizing the window, the layout will be resized in the same way.

How do I get the SelectedItem or SelectedIndex of ListView in vb.net?

Here's the answer that I found for my question:

urlList1.FocusedItem.Index

And I am getting selected item value by:

urlList1.Items(urlList1.FocusedItem.Index).SubItems(0).Text

How to "z-index" to make a menu always on top of the content

You most probably don't need z-index to do that. You can use relative and absolute positioning.

I advise you to take a better look at css positioning and the difference between relative and absolute positioning... I saw you're setting position: absolute; to an element and trying to float that element. It won't work friend! When you understand positioning in CSS it will make your work a lot easier! ;)

Edit: Just to be clear, positioning is not a replacement for them and I do use z-index. I just try to avoid using them. Using z-indexes everywhere seems easy and fun at first... until you have bugs related to them and find yourself having to revisit and manage z-indexes.

Make a phone call programmatically

'openURL:' is deprecated: first deprecated in iOS 10.0 - Please use openURL:options:completionHandler: instead

in Objective-c iOS 10+ use :

NSString *phoneNumber = [@"tel://" stringByAppendingString:mymobileNO.titleLabel.text];
[[UIApplication sharedApplication] openURL:[NSURL URLWithString:phoneNumber] options:@{} completionHandler:nil];

Fatal error: Allowed memory size of 268435456 bytes exhausted (tried to allocate 71 bytes)

I changed the memory limit from .htaccess and this problem got resolved.

I was trying to scan my website from one of the antivirus plugin and there I was getting this problem. I increased memory by pasting this in my .htaccess file in Wordpress folder:

php_value memory_limit 512M

After scan was over, I removed this line to make the size as it was before.

Put spacing between divs in a horizontal row?

A possible idea would be to:

  1. delete the width: 25%; float:left; from the style of your divs
  2. wrap each of the four colored divs in a div that has style="width: 25%; float:left;"

The advantage with this approach is that all four columns will have equal width and the gap between them will always be 5px * 2.

Here's what it looks like:

_x000D_
_x000D_
.cellContainer {_x000D_
  width: 25%;_x000D_
  float: left;_x000D_
}
_x000D_
<div style="width:100%; height: 200px; background-color: grey;">_x000D_
  <div class="cellContainer">_x000D_
    <div style="margin: 5px; background-color: red;">A</div>_x000D_
  </div>_x000D_
  <div class="cellContainer">_x000D_
    <div style="margin: 5px; background-color: orange;">B</div>_x000D_
  </div>_x000D_
  <div class="cellContainer">_x000D_
    <div style="margin: 5px; background-color: green;">C</div>_x000D_
  </div>_x000D_
  <div class="cellContainer">_x000D_
    <div style="margin: 5px; background-color: blue;">D</div>_x000D_
  </div>_x000D_
</div>
_x000D_
_x000D_
_x000D_

php codeigniter count rows

replace the query inside your model function with this

$query = $this->db->query("SELECT id FROM home");

in view:

echo $query->num_rows();

How to display items side-by-side without using tables?

Yes, divs and CSS are usually a better and easier way to place your HTML. There are many different ways to do this and it all depends on the context.

For instance, if you want to place an image to the right of your text, you could do it like so:

<p style="width: 500px;">
<img src="image.png" style="float: right;" />
This is some text
</p> 

And if you want to display multiple items side by side, float is also usually preferred.For example:

<div>
  <img src="image1.png" style="float: left;" />
  <img src="image2.png" style="float: left;" />
  <img src="image3.png" style="float: left;" />
</div>

Floating these images to the same side will have then laying next to each other for as long as you hava horizontal space.

How to add title to subplots in Matplotlib?

ax.set_title() should set the titles for separate subplots:

import matplotlib.pyplot as plt

if __name__ == "__main__":
    data = [1, 2, 3, 4, 5]

    fig = plt.figure()
    fig.suptitle("Title for whole figure", fontsize=16)
    ax = plt.subplot("211")
    ax.set_title("Title for first plot")
    ax.plot(data)

    ax = plt.subplot("212")
    ax.set_title("Title for second plot")
    ax.plot(data)

    plt.show()

Can you check if this code works for you? Maybe something overwrites them later?

How can I find the length of a number?

I got asked a similar question in a test.

Find a number's length without converting to string

const numbers = [1, 10, 100, 12, 123, -1, -10, -100, -12, -123, 0, -0]

const numberLength = number => {

  let length = 0
  let n = Math.abs(number)

  do {
    n /=  10
    length++
  } while (n >= 1)

  return length
}

console.log(numbers.map(numberLength)) // [ 1, 2, 3, 2, 3, 1, 2, 3, 2, 3, 1, 1 ]

Negative numbers were added to complicate it a little more, hence the Math.abs().

How to handle the click event in Listview in android?

According to my test,

  1. implements OnItemClickListener -> works.

  2. setOnItemClickListener -> works.

  3. ListView is clickable by default (API 19)

The important thing is, "click" only works to TextView (if you choose simple_list_item_1.xml as item). That means if you provide text data for the ListView, "click" works when you click on text area. Click on empty area does not trigger "click event".

IntelliJ shortcut to show a popup of methods in a class that can be searched

On linux distributions (@least on Debian with plasma) the default shortcut is

Ctrl + 0

Recursively find files with a specific extension

As a script you can use:

find "${2:-.}" -iregex ".*${1:-Robert}\.\(h\|cpp\)$" -print
  • save it as findcc
  • chmod 755 findcc

and use it as

findcc [name] [[search_direcory]]

e.g.

findcc                 # default name 'Robert' and directory .
findcc Joe             # default directory '.'
findcc Joe /somewhere  # no defaults

note you cant use

findcc /some/where    #eg without the name...

also as alternative, you can use

find "$1" -print | grep "$@" 

and

findcc directory grep_options

like

findcc . -P '/Robert\.(h|cpp)$'

Max length for client ip address

As described in the IPv6 Wikipedia article,

IPv6 addresses are normally written as eight groups of four hexadecimal digits, where each group is separated by a colon (:)

A typical IPv6 address:

2001:0db8:85a3:0000:0000:8a2e:0370:7334

This is 39 characters long. IPv6 addresses are 128 bits long, so you could conceivably use a binary(16) column, but I think I'd stick with an alphanumeric representation.

send checkbox value in PHP form

Here's how it should look like in order to return a simple Yes when it's checked.

<input type="checkbox" id="newsletter" name="newsletter" value="Yes" checked>
<label for="newsletter">i want to sign up for newsletter</label>

I also added the text as a label, it means you can click the text as well to check the box. Small but, personally I hate when sites make me aim my mouse at this tiny little check box.

When the form is submitted if the check box is checked $_POST['newsletter'] will equal Yes. Just how you are checking to see if $_POST['name'],$_POST['email'], and $_POST['tel'] are empty you could do the same.

Here is an example of how you would add this into your email on the php side:

Underneath your existing code:

$name = $_POST['name'];
$email_address = $_POST['email'];
$message = $_POST['tel'];

Add:

$newsletter = $_POST['newsletter'];
if ($newsletter != 'Yes') {
    $newsletter = 'No';
}

If the check box is checked it will add Yes in your email if it was not checked it will add No.

Java way to check if a string is palindrome

 public boolean isPalindrom(String text) {
    StringBuffer stringBuffer = new StringBuffer(text);
     return stringBuffer.reverse().toString().equals(text);
}

Error handling in AngularJS http get then construct

https://docs.angularjs.org/api/ng/service/$http

$http.get(url).success(successCallback).error(errorCallback);

Replace successCallback and errorCallback with your functions.

Edit: Laurent's answer is more correct considering he is using then. Yet I'm leaving this here as an alternative for the folks who will visit this question.

Scatter plot and Color mapping in Python

Subplot Colorbar

For subplots with scatter, you can trick a colorbar onto your axes by building the "mappable" with the help of a secondary figure and then adding it to your original plot.

As a continuation of the above example:

import numpy as np
import matplotlib.pyplot as plt

x = np.arange(10)
y = x
t = x
fig, (ax1, ax2) = plt.subplots(1, 2)
ax1.scatter(x, y, c=t, cmap='viridis')
ax2.scatter(x, y, c=t, cmap='viridis_r')


# Build your secondary mirror axes:
fig2, (ax3, ax4) = plt.subplots(1, 2)

# Build maps that parallel the color-coded data
# NOTE 1: imshow requires a 2-D array as input
# NOTE 2: You must use the same cmap tag as above for it match
map1 = ax3.imshow(np.stack([t, t]),cmap='viridis')
map2 = ax4.imshow(np.stack([t, t]),cmap='viridis_r')

# Add your maps onto your original figure/axes
fig.colorbar(map1, ax=ax1)
fig.colorbar(map2, ax=ax2)
plt.show()

Scatter subplots with COLORBAR

Note that you will also output a secondary figure that you can ignore.

What are .iml files in Android Studio?

What are iml files in Android Studio project?

A Google search on iml file turns up:

IML is a module file created by IntelliJ IDEA, an IDE used to develop Java applications. It stores information about a development module, which may be a Java, Plugin, Android, or Maven component; saves the module paths, dependencies, and other settings.

(from this page)

why not to use gradle scripts to integrate with external modules that you add to your project.

You do "use gradle scripts to integrate with external modules", or your own modules.

However, Gradle is not IntelliJ IDEA's native project model — that is separate, held in .iml files and the metadata in .idea/ directories. In Android Studio, that stuff is largely generated out of the Gradle build scripts, which is why you are sometimes prompted to "sync project with Gradle files" when you change files like build.gradle. This is also why you don't bother putting .iml files or .idea/ in version control, as their contents will be regenerated.

If I have a team that work in different IDE's like Eclipse and AS how to make project IDE agnostic?

To a large extent, you can't.

You are welcome to have an Android project that uses the Eclipse-style directory structure (e.g., resources and manifest in the project root directory). You can teach Gradle, via build.gradle, how to find files in that structure. However, other metadata (compileSdkVersion, dependencies, etc.) will not be nearly as easily replicated.

Other alternatives include:

  • Move everybody over to another build system, like Maven, that is equally integrated (or not, depending upon your perspective) to both Eclipse and Android Studio

  • Hope that Andmore takes off soon, so that perhaps you can have an Eclipse IDE that can build Android projects from Gradle build scripts

  • Have everyone use one IDE

How to check if input is numeric in C++

When cin gets input it can't use, it sets failbit:

int n;
cin >> n;
if(!cin) // or if(cin.fail())
{
    // user didn't input a number
    cin.clear(); // reset failbit
    cin.ignore(std::numeric_limits<std::streamsize>::max(), '\n'); //skip bad input
    // next, request user reinput
}

When cin's failbit is set, use cin.clear() to reset the state of the stream, then cin.ignore() to expunge the remaining input, and then request that the user re-input. The stream will misbehave so long as the failure state is set and the stream contains bad input.

Firebase FCM notifications click_action payload

In Web, simply add the url you want to open:

{  
  "condition": "'test-topic' in topics || 'test-topic-2' in topics",  
  "notification": {
            "title": "FCM Message with condition and link",
            "body": "This is a Firebase Cloud Messaging Topic Message!",            
            "click_action": "https://yoururl.here"
        }
}