Programs & Examples On #Computational finance

How can I simulate a print statement in MySQL?

to take output in MySQL you can use if statement SYNTAX:

if(condition,if_true,if_false)

the if_true and if_false can be used to verify and to show output as there is no print statement in the MySQL

How to find the 'sizeof' (a pointer pointing to an array)?

No, you can't. The compiler doesn't know what the pointer is pointing to. There are tricks, like ending the array with a known out-of-band value and then counting the size up until that value, but that's not using sizeof().

Another trick is the one mentioned by Zan, which is to stash the size somewhere. For example, if you're dynamically allocating the array, allocate a block one int bigger than the one you need, stash the size in the first int, and return ptr+1 as the pointer to the array. When you need the size, decrement the pointer and peek at the stashed value. Just remember to free the whole block starting from the beginning, and not just the array.

Unable to start the mysql server in ubuntu

I think this is because you are using client software and not the server.

  • mysql is client
  • mysqld is the server

Try: sudo service mysqld start

To check that service is running use: ps -ef | grep mysql | grep -v grep.

Uninstalling:

sudo apt-get purge mysql-server
sudo apt-get autoremove
sudo apt-get autoclean

Re-Installing:

sudo apt-get update
sudo apt-get install mysql-server

Backup entire folder before doing this:

sudo rm /etc/apt/apt.conf.d/50unattended-upgrades*
sudo apt-get update
sudo apt-get upgrade

Writing a new line to file in PHP (line feed)

PHP_EOL is a predefined constant in PHP since PHP 4.3.10 and PHP 5.0.2. See the manual posting:

Using this will save you extra coding on cross platform developments.

IE.

$data = 'some data'.PHP_EOL;
$fp = fopen('somefile', 'a');
fwrite($fp, $data);

If you looped through this twice you would see in 'somefile':

some data
some data

How to put a component inside another component in Angular2?

You don't put a component in directives

You register it in @NgModule declarations:

@NgModule({
  imports: [ BrowserModule ],
  declarations: [ App , MyChildComponent ],
  bootstrap: [ App ]
})

and then You just put it in the Parent's Template HTML as : <my-child></my-child>

That's it.

Error occurred during initialization of VM Could not reserve enough space for object heap Could not create the Java virtual machine

This might also occur if you are running on 64-bit Machine with 32-bit JVM (JDK), switch it to 64-bit JVM. Check your (Right Click on My Computer --> Properties) Control Panel\System and Security\System --> Advanced System Settings -->Advanced Tab--> Environment Variables --> JAVA_HOME...

Find index of a value in an array

This solution helped me more, from msdn microsoft:

var result =  query.AsEnumerable().Select((x, index) =>
              new { index,x.Id,x.FirstName});

query is your toList() query.

How to trap on UIViewAlertForUnsatisfiableConstraints?

This post helped me A LOT!

I added UIViewAlertForUnsatisfiableConstraints symbolic breakpoint with suggested action:

Obj-C project

po [[UIWindow keyWindow] _autolayoutTrace]

Symbolic breakpoint with custom action in Objective-C project

Swift project

expr -l objc++ -O -- [[UIWindow keyWindow] _autolayoutTrace]

Symbolic breakpoint with custom action

With this hint, the log became more detailed, and It was easier for me identify which view had the constraint broken.

UIWindow:0x7f88a8e4a4a0
|   UILayoutContainerView:0x7f88a8f23b70
|   |   UINavigationTransitionView:0x7f88a8ca1970
|   |   |   UIViewControllerWrapperView:0x7f88a8f2aab0
|   |   |   |   •UIView:0x7f88a8ca2880
|   |   |   |   |   *UIView:0x7f88a8ca2a10
|   |   |   |   |   |   *UIButton:0x7f88a8c98820'Archived'
|   |   |   |   |   |   |   UIButtonLabel:0x7f88a8cb0e30'Archived'
|   |   |   |   |   |   *UIButton:0x7f88a8ca22d0'Download'
|   |   |   |   |   |   |   UIButtonLabel:0x7f88a8cb04e0'Download'
|   |   |   |   |   |   *UIButton:0x7f88a8ca1580'Deleted'
|   |   |   |   |   |   |   UIButtonLabel:0x7f88a8caf100'Deleted'
|   |   |   |   |   *UIView:0x7f88a8ca33e0
|   |   |   |   |   *_UILayoutGuide:0x7f88a8ca35b0
|   |   |   |   |   *_UILayoutGuide:0x7f88a8ca4090
|   |   |   |   |   _UIPageViewControllerContentView:0x7f88a8f1a390
|   |   |   |   |   |   _UIQueuingScrollView:0x7f88aa031c00
|   |   |   |   |   |   |   UIView:0x7f88a8f38070
|   |   |   |   |   |   |   UIView:0x7f88a8f381e0
|   |   |   |   |   |   |   |   •UIView:0x7f88a8f39fa0, MISSING HOST CONSTRAINTS
|   |   |   |   |   |   |   |   |   *UIButton:0x7f88a8cb9bf0'Retrieve data'- AMBIGUOUS LAYOUT for UIButton:0x7f88a8cb9bf0'Retrieve data'.minX{id: 170}, UIButton:0x7f88a8cb9bf0'Retrieve data'.minY{id: 171}
|   |   |   |   |   |   |   |   |   *UIImageView:0x7f88a8f3ad80- AMBIGUOUS LAYOUT for UIImageView:0x7f88a8f3ad80.minX{id: 172}, UIImageView:0x7f88a8f3ad80.minY{id: 173}
|   |   |   |   |   |   |   |   |   *App.RecordInfoView:0x7f88a8cbe530- AMBIGUOUS LAYOUT for App.RecordInfoView:0x7f88a8cbe530.minX{id: 174}, App.RecordInfoView:0x7f88a8cbe530.minY{id: 175}, App.RecordInfoView:0x7f88a8cbe530.Width{id: 176}, App.RecordInfoView:0x7f88a8cbe530.Height{id: 177}
|   |   |   |   |   |   |   |   |   |   +UIView:0x7f88a8cc1d30- AMBIGUOUS LAYOUT for UIView:0x7f88a8cc1d30.minX{id: 178}, UIView:0x7f88a8cc1d30.minY{id: 179}, UIView:0x7f88a8cc1d30.Width{id: 180}, UIView:0x7f88a8cc1d30.Height{id: 181}
|   |   |   |   |   |   |   |   |   |   |   *UIView:0x7f88a8cc1ec0- AMBIGUOUS LAYOUT for UIView:0x7f88a8cc1ec0.minX{id: 153}, UIView:0x7f88a8cc1ec0.minY{id: 151}, UIView:0x7f88a8cc1ec0.Width{id: 154}, UIView:0x7f88a8cc1ec0.Height{id: 165}
|   |   |   |   |   |   |   |   |   |   |   |   *UIView:0x7f88a8e68e10- AMBIGUOUS LAYOUT for UIView:0x7f88a8e68e10.minX{id: 155}, UIView:0x7f88a8e68e10.minY{id: 150}, UIView:0x7f88a8e68e10.Width{id: 156}
|   |   |   |   |   |   |   |   |   |   |   |   *UIImageView:0x7f88a8e65de0- AMBIGUOUS LAYOUT for UIImageView:0x7f88a8e65de0.minX{id: 159}, UIImageView:0x7f88a8e65de0.minY{id: 182}
|   |   |   |   |   |   |   |   |   |   |   |   *UILabel:0x7f88a8e69080'8-6-2015'- AMBIGUOUS LAYOUT for UILabel:0x7f88a8e69080'8-6-2015'.minX{id: 183}, UILabel:0x7f88a8e69080'8-6-2015'.minY{id: 184}, UILabel:0x7f88a8e69080'8-6-2015'.Width{id: 185}
|   |   |   |   |   |   |   |   |   |   |   |   *UILabel:0x7f88a8cc0690'16:34'- AMBIGUOUS LAYOUT for UILabel:0x7f88a8cc0690'16:34'.minX{id: 186}, UILabel:0x7f88a8cc0690'16:34'.minY{id: 187}, UILabel:0x7f88a8cc0690'16:34'.Width{id: 188}, UILabel:0x7f88a8cc0690'16:34'.Height{id: 189}
|   |   |   |   |   |   |   |   |   |   |   |   *UIView:0x7f88a8cc2050- AMBIGUOUS LAYOUT for UIView:0x7f88a8cc2050.minX{id: 161}, UIView:0x7f88a8cc2050.minY{id: 166}, UIView:0x7f88a8cc2050.Width{id: 163}
|   |   |   |   |   |   |   |   |   |   |   |   *UIImageView:0x7f88a8e69d90- AMBIGUOUS LAYOUT for UIImageView:0x7f88a8e69d90.minX{id: 190}, UIImageView:0x7f88a8e69d90.minY{id: 191}, UIImageView:0x7f88a8e69d90.Width{id: 192}, UIImageView:0x7f88a8e69d90.Height{id: 193}
|   |   |   |   |   |   |   |   |   |   |   *UIView:0x7f88a8f3cc00
|   |   |   |   |   |   |   |   |   |   |   |   *UIView:0x7f88a8e618d0
|   |   |   |   |   |   |   |   |   |   |   |   *UIImageView:0x7f88a8e5ba10
|   |   |   |   |   |   |   |   |   |   |   |   *UIView:0x7f88a8f3cd70
|   |   |   |   |   |   |   |   |   |   |   |   *UIImageView:0x7f88a8e58e10
|   |   |   |   |   |   |   |   |   |   |   |   *UIImageView:0x7f88a8e5e7a0
|   |   |   |   |   |   |   |   |   |   |   |   *UIView:0x7f88a8f3cee0
|   |   |   |   |   |   |   |   |   |   |   *UIView:0x7f88a8f3dc70
|   |   |   |   |   |   |   |   |   |   |   |   *UIView:0x7f88a8e64dd0
|   |   |   |   |   |   |   |   |   |   |   |   *UILabel:0x7f88a8e65290'Average flow rate'
|   |   |   |   |   |   |   |   |   |   |   |   *UILabel:0x7f88a8e712d0'177.0 ml/s'
|   |   |   |   |   |   |   |   |   |   |   |   *UILabel:0x7f88a8c97150'1299.4'
|   |   |   |   |   |   |   |   |   |   |   |   *UIView:0x7f88a8f3dde0
|   |   |   |   |   |   |   |   |   |   |   |   *UILabel:0x7f88a8f3df50'Maximum flow rate'
|   |   |   |   |   |   |   |   |   |   |   |   *UILabel:0x7f88a8cbfdb0'371.6 ml/s'
|   |   |   |   |   |   |   |   |   |   |   |   *UILabel:0x7f88a8cc0230'873.5'
|   |   |   |   |   |   |   |   |   |   |   |   *UIView:0x7f88a8f3e2a0
|   |   |   |   |   |   |   |   |   |   |   |   *UILabel:0x7f88a8f3e410'Total volume'
|   |   |   |   |   |   |   |   |   |   |   |   *UILabel:0x7f88a8cc0f20'371.6 ml'
|   |   |   |   |   |   |   |   |   |   |   |   *UIView:0x7f88a8f3e870
|   |   |   |   |   |   |   |   |   |   |   |   *UILabel:0x7f88a8f3ea00'Time do max. flow'
|   |   |   |   |   |   |   |   |   |   |   |   *UILabel:0x7f88a8cc0ac0'3.6 s'
|   |   |   |   |   |   |   |   |   |   |   |   *UIView:0x7f88a8f3ee10
|   |   |   |   |   |   |   |   |   |   |   |   *UILabel:0x7f88a8f3efa0'Flow time'
|   |   |   |   |   |   |   |   |   |   |   |   *UILabel:0x7f88a8cbf980'2.1 s'
|   |   |   |   |   |   |   |   |   |   |   |   *UIView:0x7f88a8f3f3e0
|   |   |   |   |   |   |   |   |   |   |   |   *UILabel:0x7f88a8f3f570'Voiding time'
|   |   |   |   |   |   |   |   |   |   |   |   *UILabel:0x7f88a8cc17e0'3.5 s'
|   |   |   |   |   |   |   |   |   |   |   |   *UIView:0x7f88a8f3f9a0
|   |   |   |   |   |   |   |   |   |   |   |   *UILabel:0x7f88a8f3fb30'Voiding delay'
|   |   |   |   |   |   |   |   |   |   |   |   *UILabel:0x7f88a8cc1380'1.0 s'
|   |   |   |   |   |   |   |   |   |   |   |   *UIView:0x7f88a8e65000
|   |   |   |   |   |   |   |   |   |   |   |   *UIButton:0x7f88a8e52f20'Show'
|   |   |   |   |   |   |   |   |   |   |   |   *UIImageView:0x7f88a8e6e1d0
|   |   |   |   |   |   |   |   |   |   |   |   *UIButton:0x7f88a8e52c90'Send'
|   |   |   |   |   |   |   |   |   |   |   |   *UIImageView:0x7f88a8e61bb0
|   |   |   |   |   |   |   |   |   |   |   |   *UIButton:0x7f88a8e528e0'Delete'
|   |   |   |   |   |   |   |   |   |   |   |   *UIImageView:0x7f88a8e6b3f0
|   |   |   |   |   |   |   |   |   |   |   |   *UIView:0x7f88a8f3ff60
|   |   |   |   |   |   |   |   |   *UIActivityIndicatorView:0x7f88a8cba080
|   |   |   |   |   |   |   |   |   |   UIImageView:0x7f88a8cba700
|   |   |   |   |   |   |   |   |   *_UILayoutGuide:0x7f88a8cc3150
|   |   |   |   |   |   |   |   |   *_UILayoutGuide:0x7f88a8cc3b10
|   |   |   |   |   |   |   UIView:0x7f88a8f339c0
|   |   UINavigationBar:0x7f88a8c96810
|   |   |   _UINavigationBarBackground:0x7f88a8e45c00
|   |   |   |   UIImageView:0x7f88a8e46410
|   |   |   UINavigationItemView:0x7f88a8c97520'App'
|   |   |   |   UILabel:0x7f88a8c97cc0'App'
|   |   |   UINavigationButton:0x7f88a8e3e850
|   |   |   |   UIImageView:0x7f88a8e445b0
|   |   |   _UINavigationBarBackIndicatorView:0x7f88a8f2b530

Legend:
    * - is laid out with auto layout
    + - is laid out manually, but is represented in the layout engine because translatesAutoresizingMaskIntoConstraints = YES
    • - layout engine host

Then I paused execution Pause and I changed problematic view's background color with the command (replacing 0x7f88a8cc2050 with the memory address of your object of course)...

Obj-C

expr ((UIView *)0x7f88a8cc2050).backgroundColor = [UIColor redColor]

Swift 3.0

expr -l Swift -- import UIKit
expr -l Swift -- unsafeBitCast(0x7f88a8cc2050, to: UIView.self).backgroundColor = UIColor.red

... and the result It was awesome!

Hinted View

Simply amazing! Hope It helps.

How to set 00:00:00 using moment.js

var time = moment().toDate();  // This will return a copy of the Date that the moment uses

time.setHours(0);
time.setMinutes(0);
time.setSeconds(0);
time.setMilliseconds(0);

What Are Some Good .NET Profilers?

Unfortunate most of the profilers I tried failed when used with tail calls, most notably ANTS. I just end up writing my own. There is a simple implementation on CodeProject that you can use as a base.

Break when a value changes using the Visual Studio debugger

Really old post but in case someone is unaware...

In Visual Studio 2015, you can place a breakpoint on the set accessor of an Auto-Implemented Property and the debugger will break when the property is updated

public bool IsUpdated
{
    get;
    set;    //set breakpoint on this line
}

Update

Alternatively; @AbdulRaufMujahid has pointed out in the comments that if the auto implemented property is on a single line, you can position your cursor at the get; or set; and hit F9 and a breakpoint will be placed accordingly. Nice!

public bool IsUpdated { get; set; }

How do I edit SSIS package files?

You need the Business Intelligence Studio ..I've checked and my version of VS2008 Pro doesn't have them installed.

Have a look at this link:

http://www.microsoft.com/downloads/details.aspx?familyid=3C856B93-369F-4C6F-9357-C35384179543&displaylang=en

Visual Studio build fails: unable to copy exe-file from obj\debug to bin\debug

I faced the same error.

I solved the problem by deleting all the contents of bin folders of all the dependent projects/libraries.

This error mainly happens due to version changes.

How to Change Font Size in drawString Java

Because you can't count on a particular font being available, a good approach is to derive a new font from the current font. This gives you the same family, weight, etc. just larger...

Font currentFont = g.getFont();
Font newFont = currentFont.deriveFont(currentFont.getSize() * 1.4F);
g.setFont(newFont);

You can also use TextAttribute.

Map<TextAttribute, Object> attributes = new HashMap<>();

attributes.put(TextAttribute.FAMILY, currentFont.getFamily());
attributes.put(TextAttribute.WEIGHT, TextAttribute.WEIGHT_SEMIBOLD);
attributes.put(TextAttribute.SIZE, (int) (currentFont.getSize() * 1.4));
myFont = Font.getFont(attributes);

g.setFont(myFont);

The TextAttribute method often gives one even greater flexibility. For example, you can set the weight to semi-bold, as in the example above.

One last suggestion... Because the resolution of monitors can be different and continues to increase with technology, avoid adding a specific amount (such as getSize()+2 or getSize()+4) and consider multiplying instead. This way, your new font is consistently proportional to the "current" font (getSize() * 1.4), and you won't be editing your code when you get one of those nice 4K monitors.

Preloading images with jQuery

I usually use this snippet of code on my projects for the loading of the images in a page. You can see the result here https://jsfiddle.net/ftor34ey/

<script src="https://ajax.googleapis.com/ajax/libs/jquery/3.5.1/jquery.min.js"></script>

<img src="https://live.staticflickr.com/65535/50020763321_d61d49e505_k_d.jpg" width="100" />
<img src="https://live.staticflickr.com/65535/50021019427_692a8167e9_k_d.jpg" width="100" />
<img src="https://live.staticflickr.com/65535/50020228418_d730efe386_k_d.jpg" width="100" />
<img src="https://live.staticflickr.com/65535/50020230828_7ef175d07c_k_d.jpg" width="100" />

<div style="background-image: url(https://live.staticflickr.com/65535/50020765826_e8da0aacca_k_d.jpg);"></div>
<style>
    .bg {
        background-image: url("https://live.staticflickr.com/65535/50020765651_af0962c22e_k_d.jpg");
    }
</style>
<div class="bg"></div>

<div id="loadingProgress"></div>

The script save in an array all the src and background-image of the page and load all of them.

You can see/read/show the progress of the loading by the var loadCount.

let backgroundImageArray = [];

function backgroundLoading(i) {

    let loadCount = 0;

    let img = new Image();
    $(img).on('load', function () {

        if (i < backgroundImageArray.length) {

            loadCount = parseInt(((100 / backgroundImageArray.length) * i));
            backgroundLoading(i + 1);

        } else {

            loadCount = 100;
            // do something when the page finished to load all the images
            console.log('loading completed!!!');
            $('#loadingProgress').append('<div>loading completed!!!</div>');

        }

        console.log(loadCount + '%');
        $('#loadingProgress').append('<div>' + loadCount + '%</div>');

    }).attr('src', backgroundImageArray[i - 1]);

}

$(document).ready(function () {

    $('*').each(function () {

        var backgroundImage = $(this).css('background-image');
        var putInArray = false;

        var check = backgroundImage.substr(0, 3);

        if (check == 'url') {

            backgroundImage = backgroundImage.split('url(').join('').split(')').join('');
            backgroundImage = backgroundImage.replace('"', '');
            backgroundImage = backgroundImage.replace('"', '');

            if (backgroundImage.substr(0, 4) == 'http') {
                backgroundImage = backgroundImage;
            }
            putInArray = true;

        } else if ($(this).get(0).tagName == 'IMG') {

            backgroundImage = $(this).attr('src');
            putInArray = true;

        }

        if (putInArray) {
            backgroundImageArray[backgroundImageArray.length] = backgroundImage;
        }

    });

    backgroundLoading(1);

});

Setting size for icon in CSS

this works for me try it.

height:1rem;
font-size: 3.75em;

jquery/javascript convert date string to date

If you're running with jQuery you can use the datepicker UI library's parseDate function to convert your string to a date:

var d = $.datepicker.parseDate("DD, MM dd, yy",  "Sunday, February 28, 2010");

and then follow it up with the formatDate method to get it to the string format you want

var datestrInNewFormat = $.datepicker.formatDate( "mm/dd/yy", d);

If you're not running with jQuery of course its probably not the best plan given you'd need jQuery core as well as the datepicker UI module... best to go with the suggestion from Segfault above to use date.js.

HTH

What is the difference between 0.0.0.0, 127.0.0.1 and localhost?

127.0.0.1 is normally the IP address assigned to the "loopback" or local-only interface. This is a "fake" network adapter that can only communicate within the same host. It's often used when you want a network-capable application to only serve clients on the same host. A process that is listening on 127.0.0.1 for connections will only receive local connections on that socket.

"localhost" is normally the hostname for the 127.0.0.1 IP address. It's usually set in /etc/hosts (or the Windows equivalent named "hosts" somewhere under %WINDIR%). You can use it just like any other hostname - try "ping localhost" to see how it resolves to 127.0.0.1.

0.0.0.0 has a couple of different meanings, but in this context, when a server is told to listen on 0.0.0.0 that means "listen on every available network interface". The loopback adapter with IP address 127.0.0.1 from the perspective of the server process looks just like any other network adapter on the machine, so a server told to listen on 0.0.0.0 will accept connections on that interface too.

That hopefully answers the IP side of your question. I'm not familiar with Jekyll or Vagrant, but I'm guessing that your port forwarding 8080 => 4000 is somehow bound to a particular network adapter, so it isn't in the path when you connect locally to 127.0.0.1

How to find specific lines in a table using Selenium?

(.//*[table-locator])[n]

where n represents the specific line.

Save text file UTF-8 encoded with VBA

I looked into the answer from Máta whose name hints at encoding qualifications and experience. The VBA docs say CreateTextFile(filename, [overwrite [, unicode]]) creates a file "as a Unicode or ASCII file. The value is True if the file is created as a Unicode file; False if it's created as an ASCII file. If omitted, an ASCII file is assumed." It's fine that a file stores unicode characters, but in what encoding? Unencoded unicode can't be represented in a file.

The VBA doc page for OpenTextFile(filename[, iomode[, create[, format]]]) offers a third option for the format:

  • TriStateDefault 2 "opens the file using the system default."
  • TriStateTrue 1 "opens the file as Unicode."
  • TriStateFalse 0 "opens the file as ASCII."

Máta passes -1 for this argument.

Judging from VB.NET documentation (not VBA but I think reflects realities about how underlying Windows OS represents unicode strings and echoes up into MS Office, I don't know) the system default is an encoding using 1 byte/unicode character using an ANSI code page for the locale. UnicodeEncoding is UTF-16. The docs also describe UTF-8 is also a "Unicode encoding," which makes sense to me. But I don't yet know how to specify UTF-8 for VBA output nor be confident that the data I write to disk with the OpenTextFile(,,,1) is UTF-16 encoded. Tamalek's post is helpful.

Space between border and content? / Border distance from content?

Its possible using pseudo element (after).
I have added to the original code a

position:relative
and some margin.
Here is the modified JSFiddle: http://jsfiddle.net/r4UAp/86/

#content{
  width: 100px;
  min-height: 100px;
  margin: 20px auto;
  border-style: ridge;
  border-color: #567498;
  border-spacing:10px;
  position:relative;
  background:#000;
}
#content:after {
  content: '';
  position: absolute;
  top: -15px;
  left: -15px;
  right: -15px;
  bottom: -15px;
  border: red 2px solid;
}

Is there a developers api for craigslist.org

Good news everybody! Craigslist has actually released a bulk posting api now!

Enjoy

Python: Ignore 'Incorrect padding' error when base64 decoding

As said in other responses, there are various ways in which base64 data could be corrupted.

However, as Wikipedia says, removing the padding (the '=' characters at the end of base64 encoded data) is "lossless":

From a theoretical point of view, the padding character is not needed, since the number of missing bytes can be calculated from the number of Base64 digits.

So if this is really the only thing "wrong" with your base64 data, the padding can just be added back. I came up with this to be able to parse "data" URLs in WeasyPrint, some of which were base64 without padding:

import base64
import re

def decode_base64(data, altchars=b'+/'):
    """Decode base64, padding being optional.

    :param data: Base64 data as an ASCII byte string
    :returns: The decoded byte string.

    """
    data = re.sub(rb'[^a-zA-Z0-9%s]+' % altchars, b'', data)  # normalize
    missing_padding = len(data) % 4
    if missing_padding:
        data += b'='* (4 - missing_padding)
    return base64.b64decode(data, altchars)

Tests for this function: weasyprint/tests/test_css.py#L68

How can I see the raw SQL queries Django is running?

For Django 2.2:

As most of the answers did not helped me much when using ./manage.py shell. Finally i found the answer. Hope this helps to someone.

To view all the queries:

from django.db import connection
connection.queries

To view query for a single query:

q=Query.objects.all()
q.query.__str__()

q.query just displaying the object for me. Using the __str__()(String representation) displayed the full query.

How to handle-escape both single and double quotes in an SQL-Update statement

You can escape the quotes with a backslash:

"I asked my son's teacher, \"How is my son doing now?\""

Rename a file in C#

Take a look at System.IO.File.Move, "move" the file to a new name.

System.IO.File.Move("oldfilename", "newfilename");

Hibernate: failed to lazily initialize a collection of role, no session or session was closed

You're most likely closing the session inside of the RoleDao. If you close the session then try to access a field on an object that was lazy-loaded, you will get this exception. You should probably open and close the session/transaction in your test.

How can I style a PHP echo text?

You can "style echo" with adding new HTML code.

echo '<span class="city">' . $ip['cityName'] . '</span>';

How to hide a div after some time period?

_x000D_
_x000D_
$().ready(function(){_x000D_
_x000D_
  $('div.alert').delay(1500);_x000D_
   $('div.alert').hide(1000);_x000D_
});
_x000D_
div.alert{_x000D_
color: green;_x000D_
background-color: rgb(50,200,50, .5);_x000D_
padding: 10px;_x000D_
text-align: center;_x000D_
}
_x000D_
<script src="https://ajax.googleapis.com/ajax/libs/jquery/2.1.1/jquery.min.js"></script>_x000D_
_x000D_
<div class="alert"><p>Inserted Successfully . . .</p></div>
_x000D_
_x000D_
_x000D_

How to sort pandas data frame using values from several columns?

The dataframe.sort() method is - so my understanding - deprecated in pandas > 0.18. In order to solve your problem you should use dataframe.sort_values() instead:

f.sort_values(by=["c1","c2"], ascending=[False, True])

The output looks like this:

    c1  c2
    3   10
    2   15
    2   30
    2   100
    1   20

What should I do when 'svn cleanup' fails?

When starting all over is not an option...

I deleted the log file in the .svn directory (I also deleted the offending file in .svn/props-base), did a cleanup, and resumed my update.

How to overload functions in javascript?

I tried to develop an elegant solution to this problem described here. And you can find the demo here. The usage looks like this:

var out = def({
    'int': function(a) {
        alert('Here is int '+a);
    },

    'float': function(a) {
        alert('Here is float '+a);
    },

    'string': function(a) {
        alert('Here is string '+a);
    },

    'int,string': function(a, b) {
        alert('Here is an int '+a+' and a string '+b);
    },
    'default': function(obj) {
        alert('Here is some other value '+ obj);
    }

});

out('ten');
out(1);
out(2, 'robot');
out(2.5);
out(true);

The methods used to achieve this:

var def = function(functions, parent) {
 return function() {
    var types = [];
    var args = [];
    eachArg(arguments, function(i, elem) {
        args.push(elem);
        types.push(whatis(elem));
    });
    if(functions.hasOwnProperty(types.join())) {
        return functions[types.join()].apply(parent, args);
    } else {
        if (typeof functions === 'function')
            return functions.apply(parent, args);
        if (functions.hasOwnProperty('default'))
            return functions['default'].apply(parent, args);        
    }
  };
};

var eachArg = function(args, fn) {
 var i = 0;
 while (args.hasOwnProperty(i)) {
    if(fn !== undefined)
        fn(i, args[i]);
    i++;
 }
 return i-1;
};

var whatis = function(val) {

 if(val === undefined)
    return 'undefined';
 if(val === null)
    return 'null';

 var type = typeof val;

 if(type === 'object') {
    if(val.hasOwnProperty('length') && val.hasOwnProperty('push'))
        return 'array';
    if(val.hasOwnProperty('getDate') && val.hasOwnProperty('toLocaleTimeString'))
        return 'date';
    if(val.hasOwnProperty('toExponential'))
        type = 'number';
    if(val.hasOwnProperty('substring') && val.hasOwnProperty('length'))
        return 'string';
 }

 if(type === 'number') {
    if(val.toString().indexOf('.') > 0)
        return 'float';
    else
        return 'int';
 }

 return type;
};

What strategies and tools are useful for finding memory leaks in .NET?

After one of my fixes for managed application I had the same thing, like how to verify that my application will not have the same memory leak after my next change, so I've wrote something like Object Release Verification framework, please take a look on the NuGet package ObjectReleaseVerification. You can find a sample here https://github.com/outcoldman/OutcoldSolutions-ObjectReleaseVerification-Sample, and information about this sample http://outcoldman.ru/en/blog/show/322

Program does not contain a static 'Main' method suitable for an entry point

As what, I guess pixparker wanted to say, but remained to be not clear enough, for me at least, do ensure that... All "Other Projects" have an "Output Type" of "Class Library" selected while... Only "One Project" being selected as either "Window Application" or "Console Application" output.

Creating a JSON array in C#

Also , with Anonymous types ( I prefer not to do this) -- this is just another approach.

void Main()
{
    var x = new
    {
        items = new[]
        {
            new
            {
                name = "command", index = "X", optional = "0"
            },
            new
            {
                name = "command", index = "X", optional = "0"
            }
        }
    };
    JavaScriptSerializer js = new JavaScriptSerializer(); //system.web.extension assembly....
    Console.WriteLine(js.Serialize(x));
}

result :

{"items":[{"name":"command","index":"X","optional":"0"},{"name":"command","index":"X","optional":"0"}]}

Anaconda export Environment file

I find exporting the packages in string format only is more portable than exporting the whole conda environment. As the previous answer already suggested:

$ conda list -e > requirements.txt

However, this requirements.txt contains build numbers which are not portable between operating systems, e.g. between Mac and Ubuntu. In conda env export we have the option --no-builds but not with conda list -e, so we can remove the build number by issuing the following command:

$ sed -i -E "s/^(.*\=.*)(\=.*)/\1/" requirements.txt 

And recreate the environment on another computer:

conda create -n recreated_env --file requirements.txt 

How do you create a custom AuthorizeAttribute in ASP.NET Core?

You can create your own AuthorizationHandler that will find custom attributes on your Controllers and Actions, and pass them to the HandleRequirementAsync method.

public abstract class AttributeAuthorizationHandler<TRequirement, TAttribute> : AuthorizationHandler<TRequirement> where TRequirement : IAuthorizationRequirement where TAttribute : Attribute
{
    protected override Task HandleRequirementAsync(AuthorizationHandlerContext context, TRequirement requirement)
    {
        var attributes = new List<TAttribute>();

        var action = (context.Resource as AuthorizationFilterContext)?.ActionDescriptor as ControllerActionDescriptor;
        if (action != null)
        {
            attributes.AddRange(GetAttributes(action.ControllerTypeInfo.UnderlyingSystemType));
            attributes.AddRange(GetAttributes(action.MethodInfo));
        }

        return HandleRequirementAsync(context, requirement, attributes);
    }

    protected abstract Task HandleRequirementAsync(AuthorizationHandlerContext context, TRequirement requirement, IEnumerable<TAttribute> attributes);

    private static IEnumerable<TAttribute> GetAttributes(MemberInfo memberInfo)
    {
        return memberInfo.GetCustomAttributes(typeof(TAttribute), false).Cast<TAttribute>();
    }
}

Then you can use it for any custom attributes you need on your controllers or actions. For example to add permission requirements. Just create your custom attribute.

[AttributeUsage(AttributeTargets.Class | AttributeTargets.Method, AllowMultiple = true)]
public class PermissionAttribute : AuthorizeAttribute
{
    public string Name { get; }

    public PermissionAttribute(string name) : base("Permission")
    {
        Name = name;
    }
}

Then create a Requirement to add to your Policy

public class PermissionAuthorizationRequirement : IAuthorizationRequirement
{
    //Add any custom requirement properties if you have them
}

Then create the AuthorizationHandler for your custom attribute, inheriting the AttributeAuthorizationHandler that we created earlier. It will be passed an IEnumerable for all your custom attributes in the HandleRequirementsAsync method, accumulated from your Controller and Action.

public class PermissionAuthorizationHandler : AttributeAuthorizationHandler<PermissionAuthorizationRequirement, PermissionAttribute>
{
    protected override async Task HandleRequirementAsync(AuthorizationHandlerContext context, PermissionAuthorizationRequirement requirement, IEnumerable<PermissionAttribute> attributes)
    {
        foreach (var permissionAttribute in attributes)
        {
            if (!await AuthorizeAsync(context.User, permissionAttribute.Name))
            {
                return;
            }
        }

        context.Succeed(requirement);
    }

    private Task<bool> AuthorizeAsync(ClaimsPrincipal user, string permission)
    {
        //Implement your custom user permission logic here
    }
}

And finally, in your Startup.cs ConfigureServices method, add your custom AuthorizationHandler to the services, and add your Policy.

        services.AddSingleton<IAuthorizationHandler, PermissionAuthorizationHandler>();

        services.AddAuthorization(options =>
        {
            options.AddPolicy("Permission", policyBuilder =>
            {
                policyBuilder.Requirements.Add(new PermissionAuthorizationRequirement());
            });
        });

Now you can simply decorate your Controllers and Actions with your custom attribute.

[Permission("AccessCustomers")]
public class CustomersController
{
    [Permission("AddCustomer")]
    IActionResult AddCustomer([FromBody] Customer customer)
    {
        //Add customer
    }
}

Searching for Text within Oracle Stored Procedures

If you use UPPER(text), the like '%lah%' will always return zero results. Use '%LAH%'.

How do I create a new Git branch from an old commit?

git checkout -b NEW_BRANCH_NAME COMMIT_ID

This will create a new branch called 'NEW_BRANCH_NAME' and check it out.

("check out" means "to switch to the branch")

git branch NEW_BRANCH_NAME COMMIT_ID

This just creates the new branch without checking it out.


in the comments many people seem to prefer doing this in two steps. here's how to do so in two steps:

git checkout COMMIT_ID
# you are now in the "detached head" state
git checkout -b NEW_BRANCH_NAME

CSS performance relative to translateZ(0)

It forces the browser to use hardware acceleration to access the device’s graphical processing unit (GPU) to make pixels fly. Web applications, on the other hand, run in the context of the browser, which lets the software do most (if not all) of the rendering, resulting in less horsepower for transitions. But the Web has been catching up, and most browser vendors now provide graphical hardware acceleration by means of particular CSS rules.

Using -webkit-transform: translate3d(0,0,0); will kick the GPU into action for the CSS transitions, making them smoother (higher FPS).

Note: translate3d(0,0,0) does nothing in terms of what you see. It moves the object by 0px in x,y and z axis. It's only a technique to force the hardware acceleration.

Good read here: http://www.smashingmagazine.com/2012/06/21/play-with-hardware-accelerated-css/

How to get First and Last record from a sql query?

select *
from {Table_Name}
where {x_column_name}=(
    select d.{x_column_name} 
    from (
        select rownum as rno,{x_column_name}
        from {Table_Name})d
        where d.rno=(
            select count(*)
            from {Table_Name}));

VBA Macro On Timer style to run code every set number of seconds, i.e. 120 seconds

My solution:

Option Explicit
Public datHora As Date

Function Cronometro(action As Integer) As Integer 
'This return the seconds between two >calls
Cronometro = 0
  If action = 1 Then 'Start
    datHora = Now
  End If
  If action = 2 Then 'Time until that moment
    Cronometro = DateDiff("s", datHora, Now)
  End If
End Function

How to use? Easy...

dummy= Cronometro(1) ' This starts the timer

seconds= Cronometro(2) ' This returns the seconds between the first call and this one

Best way to script remote SSH commands in Batch (Windows)

The -m switch of PuTTY takes a path to a script file as an argument, not a command.

Reference: https://the.earth.li/~sgtatham/putty/latest/htmldoc/Chapter3.html#using-cmdline-m

So you have to save your command (command_run) to a plain text file (e.g. c:\path\command.txt) and pass that to PuTTY:

putty.exe -ssh user@host -pw password -m c:\path\command.txt

Though note that you should use Plink (a command-line connection tool from PuTTY suite). It's a console application, so you can redirect its output to a file (what you cannot do with PuTTY).

A command-line syntax is identical, an output redirection added:

plink.exe -ssh user@host -pw password -m c:\path\command.txt > output.txt

See Using the command-line connection tool Plink.

And with Plink, you can actually provide the command directly on its command-line:

plink.exe -ssh user@host -pw password command > output.txt

Similar questions:
Automating running command on Linux from Windows using PuTTY
Executing command in Plink from a batch file

How to force open links in Chrome not download them?

Just found your question whilst trying to solve another problem I'm having, you will find that currently Google isn't able to perform a temporary download so therefore you have to download instead.

See: http://productforums.google.com/forum/#!topic/chrome/Drge_Zrwg-c

'Microsoft.ACE.OLEDB.12.0' provider is not registered on the local machine

If the installed "AccessDatabaseEngine" still does not help, below is solution:

You need to change the Active Solution Platform from "Any CPU" to "x86".

OLEDB Provider is Not Registered on the Local Machine

From CodeProject.com

java.lang.ClassNotFoundException: org.apache.xmlbeans.XmlObject Error

I faced a similar situation, so i replaced all the external jar files(poi-bin-3.17-20170915) and make sure you add other jar files present in lib and ooxml-lib folders.

Hope this helps!!!:)

How do I analyze a program's core dump file with GDB when it has command-line parameters?

You can analyze the core dump file using the "gdb" command.

 gdb - The GNU Debugger

 syntax:

 # gdb executable-file core-file

 example: # gdb out.txt core.xxx 

Convert an enum to List<string>

I want to add another solution: In my case, I need to use a Enum group in a drop down button list items. So they might have space, i.e. more user friendly descriptions needed:

  public enum CancelReasonsEnum
{
    [Description("In rush")]
    InRush,
    [Description("Need more coffee")]
    NeedMoreCoffee,
    [Description("Call me back in 5 minutes!")]
    In5Minutes
}

In a helper class (HelperMethods) I created the following method:

 public static List<string> GetListOfDescription<T>() where T : struct
    {
        Type t = typeof(T);
        return !t.IsEnum ? null : Enum.GetValues(t).Cast<Enum>().Select(x => x.GetDescription()).ToList();
    }

When you call this helper you will get the list of item descriptions.

 List<string> items = HelperMethods.GetListOfDescription<CancelReasonEnum>();

ADDITION: In any case, if you want to implement this method you need :GetDescription extension for enum. This is what I use.

 public static string GetDescription(this Enum value)
    {
        Type type = value.GetType();
        string name = Enum.GetName(type, value);
        if (name != null)
        {
            FieldInfo field = type.GetField(name);
            if (field != null)
            {
                DescriptionAttribute attr =Attribute.GetCustomAttribute(field,typeof(DescriptionAttribute)) as DescriptionAttribute;
                if (attr != null)
                {
                    return attr.Description;
                }
            }
        }
        return null;
        /* how to use
            MyEnum x = MyEnum.NeedMoreCoffee;
            string description = x.GetDescription();
        */

    }

Using BufferedReader to read Text File

You read line through while loop and through the loop you read the next line ,so just read it in while loop

 String s;
 while ((s=br.readLine()) != null) {
     System.out.println(s);
  }

Way to create multiline comments in Bash?

I tried the chosen answer, but found when I ran a shell script having it, the whole thing was getting printed to screen (similar to how jupyter notebooks print out everything in '''xx''' quotes) and there was an error message at end. It wasn't doing anything, but: scary. Then I realised while editing it that single-quotes can span multiple lines. So.. lets just assign the block to a variable.

x='
echo "these lines will all become comments."
echo "just make sure you don_t use single-quotes!"

ls -l
date

'

jQuery 'input' event

oninput event is very useful to track input fields changes.

However it is not supported in IE version < 9. But older IE versions has its own proprietary event onpropertychange that does the same as oninput.

So you can use it this way:

$(':input').on('input propertychange');

To have a full crossbrowser support.

Since the propertychange can be triggered for ANY property change, for example, the disabled property is changed, then you want to do include this:

$(':input').on('propertychange input', function (e) {
    var valueChanged = false;

    if (e.type=='propertychange') {
        valueChanged = e.originalEvent.propertyName=='value';
    } else {
        valueChanged = true;
    }
    if (valueChanged) {
        /* Code goes here */
    }
});

Kubernetes how to make Deployment to update image

Another option which is more suitable for debugging but worth mentioning is to check in revision history of your rollout:

$ kubectl rollout history deployment my-dep
deployment.apps/my-dep
 
REVISION  CHANGE-CAUSE
1         <none>
2         <none>
3         <none>

To see the details of each revision, run:

 kubectl rollout history deployment my-dep --revision=2

And then returning to the previous revision by running:

 $kubectl rollout undo deployment my-dep --to-revision=2

And then returning back to the new one.
Like running ctrl+z -> ctrl+y (:

(*) The CHANGE-CAUSE is <none> because you should run the updates with the --record flag - like mentioned here:

kubectl set image deployment/nginx-deployment nginx=nginx:1.16.1 --record

(**) There is a discussion regarding deprecating this flag.

How to list all tags along with the full message in git?

I prefer doing this on the command line, but if you don't mind a web interface and you use GitHub, you can visit https://github.com/user/repo/tags and click on the "..." next to each tag to display its annotation.

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

As per the other answers, set the output logging level to detailed and search there for conflicts, that will tell you where to look next.

In my case, it sent me off in a few directions looking for the source of the references, but in the end it turned out that the problem was one of my portable class library projects, it was targeting the wrong version and was pulling its own version of the references in, hence the conflicts. A quick re-target and the problem was solved.

JavaScript ternary operator example with functions

Heh, there are some pretty exciting uses of ternary syntax in your question; I like the last one the best...

x = (1 < 2) ? true : false;

The use of ternary here is totally unnecessary - you could simply write

x = (1 < 2);

Likewise, the condition element of a ternary statement is always evaluated as a Boolean value, and therefore you can express:

(IsChecked == true) ? removeItem($this) : addItem($this);

Simply as:

(IsChecked) ? removeItem($this) : addItem($this);

In fact, I would also remove the IsChecked temporary as well which leaves you with:

($this.hasClass("IsChecked")) ? removeItem($this) : addItem($this);

As for whether this is acceptable syntax, it sure is! It's a great way to reduce four lines of code into one without impacting readability. The only word of advice I would give you is to avoid nesting multiple ternary statements on the same line (that way lies madness!)

fastest way to export blobs from table into individual files

I tried using a CLR function and it was more than twice as fast as BCP. Here's my code.

Original Method:

SET @bcpCommand = 'bcp "SELECT blobcolumn FROM blobtable WHERE ID = ' + CAST(@FileID AS VARCHAR(20)) + '" queryout "' + @FileName + '" -T -c'
EXEC master..xp_cmdshell @bcpCommand

CLR Method:

declare @file varbinary(max) = (select blobcolumn from blobtable WHERE ID = @fileid)
declare @filepath nvarchar(4000) = N'c:\temp\' + @FileName
SELECT Master.dbo.WriteToFile(@file, @filepath, 0)

C# Code for the CLR function

using System;
using System.Data;
using System.Data.SqlTypes;
using System.IO;
using Microsoft.SqlServer.Server;

namespace BlobExport
{
    public class Functions
    {
      [SqlFunction]
      public static SqlString WriteToFile(SqlBytes binary, SqlString path, SqlBoolean append)
      {        
        try
        {
          if (!binary.IsNull && !path.IsNull && !append.IsNull)
          {         
            var dir = Path.GetDirectoryName(path.Value);           
            if (!Directory.Exists(dir))              
              Directory.CreateDirectory(dir);            
              using (var fs = new FileStream(path.Value, append ? FileMode.Append : FileMode.OpenOrCreate))
            {
                byte[] byteArr = binary.Value;
                for (int i = 0; i < byteArr.Length; i++)
                {
                    fs.WriteByte(byteArr[i]);
                };
            }
            return "SUCCESS";
          }
          else
             "NULL INPUT";
        }
        catch (Exception ex)
        {          
          return ex.Message;
        }
      }
    }
}

How do ACID and database transactions work?

ACID is a set of properties that you would like to apply when modifying a database.

  • Atomicity
  • Consistency
  • Isolation
  • Durability

A transaction is a set of related changes which is used to achieve some of the ACID properties. Transactions are tools to achieve the ACID properties.

Atomicity means that you can guarantee that all of a transaction happens, or none of it does; you can do complex operations as one single unit, all or nothing, and a crash, power failure, error, or anything else won't allow you to be in a state in which only some of the related changes have happened.

Consistency means that you guarantee that your data will be consistent; none of the constraints you have on related data will ever be violated.

Isolation means that one transaction cannot read data from another transaction that is not yet completed. If two transactions are executing concurrently, each one will see the world as if they were executing sequentially, and if one needs to read data that is written by another, it will have to wait until the other is finished.

Durability means that once a transaction is complete, it is guaranteed that all of the changes have been recorded to a durable medium (such as a hard disk), and the fact that the transaction has been completed is likewise recorded.

So, transactions are a mechanism for guaranteeing these properties; they are a way of grouping related actions together such that as a whole, a group of operations can be atomic, produce consistent results, be isolated from other operations, and be durably recorded.

How to select the last record of a table in SQL?

SELECT * FROM table ORDER BY Id DESC LIMIT 1

Export to CSV via PHP

Just for the record, concatenation is waaaaaay faster (I mean it) than fputcsv or even implode; And the file size is smaller:

// The data from Eternal Oblivion is an object, always
$values = (array) fetchDataFromEternalOblivion($userId, $limit = 1000);

// ----- fputcsv (slow)
// The code of @Alain Tiemblo is the best implementation
ob_start();
$csv = fopen("php://output", 'w');
fputcsv($csv, array_keys(reset($values)));
foreach ($values as $row) {
    fputcsv($csv, $row);
}
fclose($csv);
return ob_get_clean();

// ----- implode (slow, but file size is smaller)
$csv = implode(",", array_keys(reset($values))) . PHP_EOL;
foreach ($values as $row) {
    $csv .= '"' . implode('","', $row) . '"' . PHP_EOL;
}
return $csv;
// ----- concatenation (fast, file size is smaller)
// We can use one implode for the headers =D
$csv = implode(",", array_keys(reset($values))) . PHP_EOL;
$i = 1;
// This is less flexible, but we have more control over the formatting
foreach ($values as $row) {
    $csv .= '"' . $row['id'] . '",';
    $csv .= '"' . $row['name'] . '",';
    $csv .= '"' . date('d-m-Y', strtotime($row['date'])) . '",';
    $csv .= '"' . ($row['pet_name'] ?: '-' ) . '",';
    $csv .= PHP_EOL;
}
return $csv;

This is the conclusion of the optimization of several reports, from ten to thousands rows. The three examples worked fine under 1000 rows, but fails when the data was bigger.

How to run PyCharm in Ubuntu - "Run in Terminal" or "Run"?

As mentioned in the above answer, by updating the bashrc file you can run the pycharm.sh from anywhere on the linux terminal.

But if you love the icon and wants the Desktop shortcuts for the Pycharm on Ubuntu OS then follow the Below steps,

 Quick way to create Pycharm launcher. 
     1. Start Pycharm using the pycharm.sh cmd from anywhere on the terminal or start the pycharm.sh located under bin folder of the pycharm artifact.
     2. Once the Pycharm application loads, navigate to tools menu and select “Create Desktop Entry..”
     3. Check the box if you want the launcher for all users.
     4. If you Check the box i.e “Create entry for all users”, you will be asked for your password.
     5. A message should appear informing you that it was successful.
     6. Now Restart Pycharm application and you will find Pycharm in Unity dash and Application launcher.."

how to rotate text left 90 degree and cell size is adjusted according to text in html

Daniel Imms answer is excellent in regards to applying your CSS rotation to an inner element. However, it is possible to accomplish the end goal in a way that does not require JavaScript and works with longer strings of text.

Typically the whole reason to have vertical text in the first table column is to fit a long line of text in a short horizontal space and to go alongside tall rows of content (as in your example) or multiple rows of content (which I'll use in this example).

enter image description here

By using the ".rotate" class on the parent TD tag, we can not only rotate the inner DIV, but we can also set a few CSS properties on the parent TD tag that will force all of the text to stay on one line and keep the width to 1.5em. Then we can use some negative margins on the inner DIV to make sure that it centers nicely.

_x000D_
_x000D_
td {_x000D_
    border: 1px black solid;_x000D_
    padding: 5px;_x000D_
}_x000D_
.rotate {_x000D_
  text-align: center;_x000D_
  white-space: nowrap;_x000D_
  vertical-align: middle;_x000D_
  width: 1.5em;_x000D_
}_x000D_
.rotate div {_x000D_
     -moz-transform: rotate(-90.0deg);  /* FF3.5+ */_x000D_
       -o-transform: rotate(-90.0deg);  /* Opera 10.5 */_x000D_
  -webkit-transform: rotate(-90.0deg);  /* Saf3.1+, Chrome */_x000D_
             filter:  progid:DXImageTransform.Microsoft.BasicImage(rotation=0.083);  /* IE6,IE7 */_x000D_
         -ms-filter: "progid:DXImageTransform.Microsoft.BasicImage(rotation=0.083)"; /* IE8 */_x000D_
         margin-left: -10em;_x000D_
         margin-right: -10em;_x000D_
}
_x000D_
<table cellpadding="0" cellspacing="0" align="center">_x000D_
    <tr>_x000D_
        <td class='rotate' rowspan="4"><div>10 kilograms</div></td>_x000D_
        <td>B</td>_x000D_
        <td>C</td>_x000D_
        <td>D</td>_x000D_
        <td>E</td>_x000D_
    </tr>_x000D_
    <tr>_x000D_
        <td>G</td>_x000D_
        <td>H</td>_x000D_
        <td>I</td>_x000D_
        <td>J</td>_x000D_
    </tr>_x000D_
    <tr>_x000D_
        <td>L</td>_x000D_
        <td>M</td>_x000D_
        <td>N</td>_x000D_
        <td>O</td>_x000D_
    </tr>_x000D_
    <tr>_x000D_
        <td>Q</td>_x000D_
        <td>R</td>_x000D_
        <td>S</td>_x000D_
        <td>T</td>_x000D_
    </tr>_x000D_
    _x000D_
    <tr>_x000D_
        <td class='rotate' rowspan="4"><div>20 kilograms</div></td>_x000D_
        <td>B</td>_x000D_
        <td>C</td>_x000D_
        <td>D</td>_x000D_
        <td>E</td>_x000D_
    </tr>_x000D_
    <tr>_x000D_
        <td>G</td>_x000D_
        <td>H</td>_x000D_
        <td>I</td>_x000D_
        <td>J</td>_x000D_
    </tr>_x000D_
    <tr>_x000D_
        <td>L</td>_x000D_
        <td>M</td>_x000D_
        <td>N</td>_x000D_
        <td>O</td>_x000D_
    </tr>_x000D_
    <tr>_x000D_
        <td>Q</td>_x000D_
        <td>R</td>_x000D_
        <td>S</td>_x000D_
        <td>T</td>_x000D_
    </tr>_x000D_
    _x000D_
    <tr>_x000D_
        <td class='rotate' rowspan="4"><div>30 kilograms</div></td>_x000D_
        <td>B</td>_x000D_
        <td>C</td>_x000D_
        <td>D</td>_x000D_
        <td>E</td>_x000D_
    </tr>_x000D_
    <tr>_x000D_
        <td>G</td>_x000D_
        <td>H</td>_x000D_
        <td>I</td>_x000D_
        <td>J</td>_x000D_
    </tr>_x000D_
    <tr>_x000D_
        <td>L</td>_x000D_
        <td>M</td>_x000D_
        <td>N</td>_x000D_
        <td>O</td>_x000D_
    </tr>_x000D_
    <tr>_x000D_
        <td>Q</td>_x000D_
        <td>R</td>_x000D_
        <td>S</td>_x000D_
        <td>T</td>_x000D_
    </tr>_x000D_
    _x000D_
</table>
_x000D_
_x000D_
_x000D_

One thing to keep in mind with this solution is that it does not work well if the height of the row (or spanned rows) is shorter than the vertical text in the first column. It works best if you're spanning multiple rows or you have a lot of content creating tall rows.

Have fun playing around with this on jsFiddle.

Jquery submit form

You don't really need to do it all in jQuery to do that smoothly. Do it like this:

$(".nextbutton").click(function() { 
   document.forms["form1"].submit();
});

'printf' vs. 'cout' in C++

For me, the real differences which would make me go for 'cout' rather than 'printf' are:

1) << operator can be overloaded for my classes.

2) Output stream for cout can be easily changed to a file : (: copy paste :)

#include <iostream>
#include <fstream>
using namespace std;

int main ()
{
    cout << "This is sent to prompt" << endl;
    ofstream file;
    file.open ("test.txt");
    streambuf* sbuf = cout.rdbuf();
    cout.rdbuf(file.rdbuf());
    cout << "This is sent to file" << endl;
    cout.rdbuf(sbuf);
    cout << "This is also sent to prompt" << endl;
    return 0;
}

3) I find cout more readable, especially when we have many parameters.

One problem with cout is the formatting options. Formatting the data (precision, justificaton, etc.) in printf is easier.

How to set default value for form field in Symfony2?

If your form is bound to an entity, just set the default value on the entity itself using the construct method:

public function __construct()
{
    $this->field = 'default value';
}

Open Redis port for remote connections

A quick note that if you are using AWS ec2 instance then there is one more extra step that I believe is also mandatory. I missed the step-3 and it took me whole day to figure out to add an inbound rule to security group

Step 1(as previous): in your redis.conf change bind 127.0.0.1 to bind 0.0.0.0

Step2(as previous): in your redis.conf change protected-mode yes to protected-mode no

important for Amazon Ec2 Instance:

Step3: In your current ec2 machine go to the security group. add an inbound rule for custom TCP with 6379 port and select option "use from anywhere".

Is it possible to use JS to open an HTML select to show its option list?

<select id="myDropDown">
  <option>html5</option>
  <option>javascript</option>
  <option>jquery</option>
  <option>css</option>
  <option>sencha</option>
</select>

By jQuery:

var myDropDown=$("#myDropDown");
var length = $('#myDropDown> option').length;
//open dropdown
myDropDown.attr('size',length);
//close dropdown
myDropDown.attr('size',0);

By javascript:

var myDropDown=document.getElementById("myDropDown");
var length = myDropDown.options.length;
//open dropdown
myDropDown.size = length;
//close dropdown
myDropDown.size = 0;

Copied from: Open close select

MySQL: determine which database is selected?

You can always use STATUS command to get to know Current database & Current User

enter image description here

Android studio Error "Unsupported Modules Detected: Compilation is not supported for following modules"

Check in build.gradle in app you have good compile link .I have mistake with this line compile 'com.android.support:support-annotations:x.x.x' delete and work.

Best way to Bulk Insert from a C# DataTable

string connectionString= ServerName + DatabaseName + SecurityType;
using (SqlConnection connection = new SqlConnection(connectionString))
using (SqlBulkCopy bulkCopy = new SqlBulkCopy(connection)) {
    connection.Open();
    bulkCopy.DestinationTableName = "TableName";
    try {
        bulkCopy.WriteToServer(dataTableName);
    } catch (Exception e) {
        Console.Write(e.Message);
    }
}

Please note that the structure of the database table and the table name should be the same or it will throw an exception.

How to change max_allowed_packet size

in MYSQL 5.7, max_allowed_packet is at most 1G. if you want to set it to 4G, it would failed without error and warning.

Could not locate Gemfile

Is very simple. when it says 'Could not locate Gemfile' it means in the folder you are currently in or a directory you are in, there is No a file named GemFile. Therefore in your command prompt give an explicit or full path of the there folder where such file name "Gemfile" is e.g cd C:\Users\Administrator\Desktop\RubyProject\demo.

It will definitely be solved in a minute.

JQuery - Set Attribute value

$("#chk0") is refering to an element with the id chk0. You might try adding id's to the elements. Ids are unique even though the names are the same so that in jQuery you can access a single element by it's id.

How to uninstall Ruby from /usr/local?

If ruby was installed in the following way:

./configure --prefix=/usr/local
make
sudo make install

You can uninstall it in the following way:

Check installed ruby version; lets assume 2.1.2

wget http://cache.ruby-lang.org/pub/ruby/2.1/ruby-2.1.2.tar.bz2
bunzip ...
tar xfv ...
cd ruby-2.1.2
./configure --prefix=/usr/local
make
sudo checkinstall
  # will build deb or rpm package and try to install it

After installation, you can now remove the package and it will remove the directories/files/etc.

sudo rpm -e ruby # or dpkg -P ruby (for Debian-like systems)

There might be some artifacts left:

Removing ruby ...
  warning: while removing ruby, directory '/usr/local/lib/ruby/gems/2.1.0/gems' not empty so not removed.
  ...

Remove them manually.

How to format string to money

Try simple like this

 var amtf = $"{Convert.ToDecimal(amt):#0.00}";

Using python PIL to turn a RGB image into a pure black and white image

As Martin Thoma has said, you need to normally apply thresholding. But you can do this using simple vectorization which will run much faster than the for loop that is used in that answer.

The code below converts the pixels of an image into 0 (black) and 1 (white).

from PIL import Image
import numpy as np
import matplotlib.pyplot as plt

#Pixels higher than this will be 1. Otherwise 0.
THRESHOLD_VALUE = 200

#Load image and convert to greyscale
img = Image.open("photo.png")
img = img.convert("L")

imgData = np.asarray(img)
thresholdedData = (imgData > THRESHOLD_VALUE) * 1.0

plt.imshow(thresholdedData)
plt.show()

Freeing up a TCP/IP port?

As the others have said, you'll have to kill all processes that are listening on that port. The easiest way to do that would be to use the fuser(1) command. For example, to see all of the processes listening for http requests on port 80 (run as root or use sudo):

# fuser 80/tcp

If you want to kill them, then just add the -k option.

Get file size, image width and height before upload

Multiple images upload with info data preview

Using HTML5 and the File API

Example using URL API

The images sources will be a URL representing the Blob object
<img src="blob:null/026cceb9-edr4-4281-babb-b56cbf759a3d">

_x000D_
_x000D_
const EL_browse  = document.getElementById('browse');_x000D_
const EL_preview = document.getElementById('preview');_x000D_
_x000D_
const readImage  = file => {_x000D_
  if ( !(/^image\/(png|jpe?g|gif)$/).test(file.type) )_x000D_
    return EL_preview.insertAdjacentHTML('beforeend', `Unsupported format ${file.type}: ${file.name}<br>`);_x000D_
_x000D_
  const img = new Image();_x000D_
  img.addEventListener('load', () => {_x000D_
    EL_preview.appendChild(img);_x000D_
    EL_preview.insertAdjacentHTML('beforeend', `<div>${file.name} ${img.width}×${img.height} ${file.type} ${Math.round(file.size/1024)}KB<div>`);_x000D_
    window.URL.revokeObjectURL(img.src); // Free some memory_x000D_
  });_x000D_
  img.src = window.URL.createObjectURL(file);_x000D_
}_x000D_
_x000D_
EL_browse.addEventListener('change', ev => {_x000D_
  EL_preview.innerHTML = ''; // Remove old images and data_x000D_
  const files = ev.target.files;_x000D_
  if (!files || !files[0]) return alert('File upload not supported');_x000D_
  [...files].forEach( readImage );_x000D_
});
_x000D_
#preview img { max-height: 100px; }
_x000D_
<input id="browse" type="file" multiple>_x000D_
<div id="preview"></div>
_x000D_
_x000D_
_x000D_

Example using FileReader API

In case you need images sources as long Base64 encoded data strings
<img src="data:image/png;base64,iVBORw0KGg... ...lF/++TkSuQmCC=">

_x000D_
_x000D_
const EL_browse  = document.getElementById('browse');_x000D_
const EL_preview = document.getElementById('preview');_x000D_
_x000D_
const readImage = file => {_x000D_
  if ( !(/^image\/(png|jpe?g|gif)$/).test(file.type) )_x000D_
    return EL_preview.insertAdjacentHTML('beforeend', `<div>Unsupported format ${file.type}: ${file.name}</div>`);_x000D_
_x000D_
  const reader = new FileReader();_x000D_
  reader.addEventListener('load', () => {_x000D_
    const img  = new Image();_x000D_
    img.addEventListener('load', () => {_x000D_
      EL_preview.appendChild(img);_x000D_
      EL_preview.insertAdjacentHTML('beforeend', `<div>${file.name} ${img.width}×${img.height} ${file.type} ${Math.round(file.size/1024)}KB</div>`);_x000D_
    });_x000D_
    img.src = reader.result;_x000D_
  });_x000D_
  reader.readAsDataURL(file);  _x000D_
};_x000D_
_x000D_
EL_browse.addEventListener('change', ev => {_x000D_
  EL_preview.innerHTML = ''; // Clear Preview_x000D_
  const files = ev.target.files;_x000D_
  if (!files || !files[0]) return alert('File upload not supported');_x000D_
  [...files].forEach( readImage );_x000D_
});
_x000D_
#preview img { max-height: 100px; }
_x000D_
<input id="browse" type="file"  multiple>_x000D_
<div id="preview"></div>_x000D_
  
_x000D_
_x000D_
_x000D_

Validation error: "No validator could be found for type: java.lang.Integer"

As the question is asked simply use @Min(1) instead of @size on integer fields and it will work.

How to find list intersection?

Here's some Python 2 / Python 3 code that generates timing information for both list-based and set-based methods of finding the intersection of two lists.

The pure list comprehension algorithms are O(n^2), since in on a list is a linear search. The set-based algorithms are O(n), since set search is O(1), and set creation is O(n) (and converting a set to a list is also O(n)). So for sufficiently large n the set-based algorithms are faster, but for small n the overheads of creating the set(s) make them slower than the pure list comp algorithms.

#!/usr/bin/env python

''' Time list- vs set-based list intersection
    See http://stackoverflow.com/q/3697432/4014959
    Written by PM 2Ring 2015.10.16
'''

from __future__ import print_function, division
from timeit import Timer

setup = 'from __main__ import a, b'
cmd_lista = '[u for u in a if u in b]'
cmd_listb = '[u for u in b if u in a]'

cmd_lcsa = 'sa=set(a);[u for u in b if u in sa]'

cmd_seta = 'list(set(a).intersection(b))'
cmd_setb = 'list(set(b).intersection(a))'

reps = 3
loops = 50000

def do_timing(heading, cmd, setup):
    t = Timer(cmd, setup)
    r = t.repeat(reps, loops)
    r.sort()
    print(heading, r)
    return r[0]

m = 10
nums = list(range(6 * m))

for n in range(1, m + 1):
    a = nums[:6*n:2]
    b = nums[:6*n:3]
    print('\nn =', n, len(a), len(b))
    #print('\nn = %d\n%s %d\n%s %d' % (n, a, len(a), b, len(b)))
    la = do_timing('lista', cmd_lista, setup) 
    lb = do_timing('listb', cmd_listb, setup) 
    lc = do_timing('lcsa ', cmd_lcsa, setup)
    sa = do_timing('seta ', cmd_seta, setup)
    sb = do_timing('setb ', cmd_setb, setup)
    print(la/sa, lb/sa, lc/sa, la/sb, lb/sb, lc/sb)

output

n = 1 3 2
lista [0.082171916961669922, 0.082588911056518555, 0.0898590087890625]
listb [0.069530963897705078, 0.070394992828369141, 0.075379848480224609]
lcsa  [0.11858987808227539, 0.1188349723815918, 0.12825107574462891]
seta  [0.26900982856750488, 0.26902294158935547, 0.27298116683959961]
setb  [0.27218389511108398, 0.27459001541137695, 0.34307217597961426]
0.305460649521 0.258469975867 0.440838458259 0.301898526833 0.255455833892 0.435697630214

n = 2 6 4
lista [0.15915989875793457, 0.16000485420227051, 0.16551494598388672]
listb [0.13000702857971191, 0.13060092926025391, 0.13543915748596191]
lcsa  [0.18650484085083008, 0.18742108345031738, 0.19513416290283203]
seta  [0.33592700958251953, 0.34001994132995605, 0.34146714210510254]
setb  [0.29436492919921875, 0.2953648567199707, 0.30039691925048828]
0.473793098554 0.387009751735 0.555194537893 0.540689066428 0.441652573672 0.633583767462

n = 3 9 6
lista [0.27657914161682129, 0.28098297119140625, 0.28311991691589355]
listb [0.21585917472839355, 0.21679902076721191, 0.22272896766662598]
lcsa  [0.22559309005737305, 0.2271728515625, 0.2323150634765625]
seta  [0.36382699012756348, 0.36453008651733398, 0.36750602722167969]
setb  [0.34979605674743652, 0.35533690452575684, 0.36164689064025879]
0.760194128313 0.59330170819 0.62005595016 0.790686848184 0.61710008036 0.644927481902

n = 4 12 8
lista [0.39616990089416504, 0.39746403694152832, 0.41129183769226074]
listb [0.33485794067382812, 0.33914685249328613, 0.37850618362426758]
lcsa  [0.27405810356140137, 0.2745978832244873, 0.28249192237854004]
seta  [0.39211201667785645, 0.39234519004821777, 0.39317893981933594]
setb  [0.36988520622253418, 0.37011313438415527, 0.37571001052856445]
1.01034878821 0.85398540833 0.698928091731 1.07106176249 0.905302334456 0.740927452493

n = 5 15 10
lista [0.56792402267456055, 0.57422614097595215, 0.57740211486816406]
listb [0.47309303283691406, 0.47619009017944336, 0.47628307342529297]
lcsa  [0.32805585861206055, 0.32813096046447754, 0.3349759578704834]
seta  [0.40036201477050781, 0.40322518348693848, 0.40548801422119141]
setb  [0.39103078842163086, 0.39722800254821777, 0.43811702728271484]
1.41852623806 1.18166313332 0.819398061028 1.45237674242 1.20986133789 0.838951479847

n = 6 18 12
lista [0.77897095680236816, 0.78187918663024902, 0.78467702865600586]
listb [0.629547119140625, 0.63210701942443848, 0.63321495056152344]
lcsa  [0.36563992500305176, 0.36638498306274414, 0.38175487518310547]
seta  [0.46695613861083984, 0.46992206573486328, 0.47583580017089844]
setb  [0.47616910934448242, 0.47661614418029785, 0.4850609302520752]
1.66818870637 1.34819326075 0.783028414812 1.63591241329 1.32210827369 0.767878297495

n = 7 21 14
lista [0.9703209400177002, 0.9734041690826416, 1.0182771682739258]
listb [0.82394003868103027, 0.82625699043273926, 0.82796716690063477]
lcsa  [0.40975093841552734, 0.41210508346557617, 0.42286920547485352]
seta  [0.5086359977722168, 0.50968098640441895, 0.51014018058776855]
setb  [0.48688101768493652, 0.4879908561706543, 0.49204087257385254]
1.90769222837 1.61990115188 0.805587768483 1.99293236904 1.69228211566 0.841583309951

n = 8 24 16
lista [1.204819917678833, 1.2206029891967773, 1.258256196975708]
listb [1.014998197555542, 1.0206191539764404, 1.0343101024627686]
lcsa  [0.50966787338256836, 0.51018595695495605, 0.51319599151611328]
seta  [0.50310111045837402, 0.50556015968322754, 0.51335406303405762]
setb  [0.51472997665405273, 0.51948785781860352, 0.52113485336303711]
2.39478683834 2.01748351664 1.01305257092 2.34068341135 1.97190418975 0.990165516871

n = 9 27 18
lista [1.511646032333374, 1.5133969783782959, 1.5639569759368896]
listb [1.2461750507354736, 1.254518985748291, 1.2613379955291748]
lcsa  [0.5565330982208252, 0.56119203567504883, 0.56451296806335449]
seta  [0.5966339111328125, 0.60275578498840332, 0.64791703224182129]
setb  [0.54694414138793945, 0.5508568286895752, 0.55375313758850098]
2.53362406013 2.08867620074 0.932788243907 2.76380331728 2.27843203069 1.01753187594

n = 10 30 20
lista [1.7777848243713379, 2.1453688144683838, 2.4085969924926758]
listb [1.5070111751556396, 1.5202279090881348, 1.5779800415039062]
lcsa  [0.5954139232635498, 0.59703707695007324, 0.60746097564697266]
seta  [0.61563014984130859, 0.62125110626220703, 0.62354087829589844]
setb  [0.56723213195800781, 0.57257509231567383, 0.57460403442382812]
2.88774814689 2.44791645689 0.967161734066 3.13413984189 2.6567803378 1.04968299523

Generated using a 2GHz single core machine with 2GB of RAM running Python 2.6.6 on a Debian flavour of Linux (with Firefox running in the background).

These figures are only a rough guide, since the actual speeds of the various algorithms are affected differently by the proportion of elements that are in both source lists.

Typescript input onchange event.target.value

This is when you're working with a FileList Object:

onChange={(event: React.ChangeEvent<HTMLInputElement>): void => {
  const fileListObj: FileList | null = event.target.files;
  if (Object.keys(fileListObj as Object).length > 3) {
    alert('Only three images pleaseeeee :)');
  } else {
    // Do something
  }

  return;
}}

Running a simple shell script as a cronjob

What directory is file.txt in? cron runs jobs in your home directory, so unless your script cds somewhere else, that's where it's going to look for/create file.txt.

EDIT: When you refer to a file without specifying its full path (e.g. file.txt, as opposed to the full path /home/myUser/scripts/file.txt) in shell, it's taken that you're referring to a file in your current working directory. When you run a script (whether interactively or via crontab), the script's working directory has nothing at all to do with the location of the script itself; instead, it's inherited from whatever ran the script.

Thus, if you cd (change working directory) to the directory the script's in and then run it, file.txt will refer to a file in the same directory as the script. But if you don't cd there first, file.txt will refer to a file in whatever directory you happen to be in when you ran the script. For instance, if your home directory is /home/myUser, and you open a new shell and immediately run the script (as scripts/test.sh or /home/myUser/scripts/test.sh; ./test.sh won't work), it'll touch the file /home/myUser/file.txt because /home/myUser is your current working directory (and therefore the script's).

When you run a script from cron, it does essentially the same thing: it runs it with the working directory set to your home directory. Thus all file references in the script are taken relative to your home directory, unless the script cds somewhere else or specifies an absolute path to the file.

Java: Difference between the setPreferredSize() and setSize() methods in components

setSize will resize the component to the specified size.

setPreferredSize sets the preferred size. The component may not actually be this size depending on the size of the container it's in, or if the user re-sized the component manually.

How to read a CSV file from a URL with Python?

import pandas as pd
url='https://raw.githubusercontent.com/juliencohensolal/BankMarketing/master/rawData/bank-additional-full.csv'
data = pd.read_csv(url,sep=";") # use sep="," for coma separation. 
data.describe()

enter image description here

MongoDB SELECT COUNT GROUP BY

I need some extra operation based on the result of aggregate function. Finally I've found some solution for aggregate function and the operation based on the result in MongoDB. I've a collection Request with field request, source, status, requestDate.

Single Field Group By & Count:

db.Request.aggregate([
    {"$group" : {_id:"$source", count:{$sum:1}}}
])

Multiple Fields Group By & Count:

db.Request.aggregate([
    {"$group" : {_id:{source:"$source",status:"$status"}, count:{$sum:1}}}
])

Multiple Fields Group By & Count with Sort using Field:

db.Request.aggregate([
    {"$group" : {_id:{source:"$source",status:"$status"}, count:{$sum:1}}},
    {$sort:{"_id.source":1}}
])

Multiple Fields Group By & Count with Sort using Count:

db.Request.aggregate([
    {"$group" : {_id:{source:"$source",status:"$status"}, count:{$sum:1}}},
    {$sort:{"count":-1}}
])

ImportError: No module named 'Queue'

I just copy the file name Queue.py in the */lib/python2.7/ to queue.py and that solved my problem.

how to find host name from IP with out login to the host

python -c "import socket;print(socket.gethostbyaddr('127.0.0.1'))"

if you just need the name, no additional info, add [0] at the end:

python -c "import socket;print(socket.gethostbyaddr('8.8.8.8'))[0]"

Spring: how do I inject an HttpServletRequest into a request-scoped bean?

Request-scoped beans can be autowired with the request object.

private @Autowired HttpServletRequest request;

Preloading images with JavaScript

Here is my approach:

var preloadImages = function (srcs, imgs, callback) {
    var img;
    var remaining = srcs.length;
    for (var i = 0; i < srcs.length; i++) {
        img = new Image;
        img.onload = function () {
            --remaining;
            if (remaining <= 0) {
                callback();
            }
        };
        img.src = srcs[i];
        imgs.push(img);
    }
};

Using PowerShell to write a file in UTF-8 without the BOM

    [System.IO.FileInfo] $file = Get-Item -Path $FilePath 
    $sequenceBOM = New-Object System.Byte[] 3 
    $reader = $file.OpenRead() 
    $bytesRead = $reader.Read($sequenceBOM, 0, 3) 
    $reader.Dispose() 
    #A UTF-8+BOM string will start with the three following bytes. Hex: 0xEF0xBB0xBF, Decimal: 239 187 191 
    if ($bytesRead -eq 3 -and $sequenceBOM[0] -eq 239 -and $sequenceBOM[1] -eq 187 -and $sequenceBOM[2] -eq 191) 
    { 
        $utf8NoBomEncoding = New-Object System.Text.UTF8Encoding($False) 
        [System.IO.File]::WriteAllLines($FilePath, (Get-Content $FilePath), $utf8NoBomEncoding) 
        Write-Host "Remove UTF-8 BOM successfully" 
    } 
    Else 
    { 
        Write-Warning "Not UTF-8 BOM file" 
    }  

Source How to remove UTF8 Byte Order Mark (BOM) from a file using PowerShell

Get a list of dates between two dates

We used this in our HRMS System you will find it useful

SELECT CAST(DAYNAME(daydate) as CHAR) as dayname,daydate
    FROM
    (select CAST((date_add('20110101', interval H.i*100 + T.i*10 + U.i day) )as DATE) as daydate
      from erp_integers as H
    cross
      join erp_integers as T
    cross
      join erp_integers as U
     where date_add('20110101', interval H.i*100 + T.i*10 + U.i day ) <= '20110228'
    order
        by daydate ASC
        )Days

Why I can't access remote Jupyter Notebook server?

I'm using Anaconda3 on Windows 10. When you install it rembember to flag "add to Enviroment Variables".


Prerequisite: A notebook configuration file

Check to see if you have a notebook configuration file, jupyter_notebook_config.py. The default location for this file is your Jupyter folder located in your home directory:

  • Windows: C:\\Users\\USERNAME\\.jupyter\\jupyter_notebook_config.py
  • OS X: /Users/USERNAME/.jupyter/jupyter_notebook_config.py
  • Linux: /home/USERNAME/.jupyter/jupyter_notebook_config.py

If you don't already have a Jupyter folder, or if your Jupyter folder doesn't contain a notebook configuration file, run the following command:

$ jupyter notebook --generate-config

This command will create the Jupyter folder if necessary, and create notebook configuration file, jupyter_notebook_config.py, in this folder.


By default, Jupyter Notebook only accepts connections from localhost.

Edit the jupyter_notebook_config.py file as following to accept all incoming connections:

c.NotebookApp.allow_origin = '*' #allow all origins

You'll also need to change the IPs that the notebook will listen on:

c.NotebookApp.ip = '0.0.0.0' # listen on all IPs

How do I get list of methods in a Python class?

There is the dir(theobject) method to list all the fields and methods of your object (as a tuple) and the inspect module (as codeape write) to list the fields and methods with their doc (in """).

Because everything (even fields) might be called in Python, I'm not sure there is a built-in function to list only methods. You might want to try if the object you get through dir is callable or not.

Tuples( or arrays ) as Dictionary keys in C#

If you're on C# 7, you should consider using value tuples as your composite key. Value tuples typically offer better performance than the traditional reference tuples (Tuple<T1, …>) since value tuples are value types (structs), not reference types, so they avoid the memory allocation and garbage collection costs. Also, they offer conciser and more intuitive syntax, allowing for their fields to be named if you so wish. They also implement the IEquatable<T> interface needed for the dictionary.

var dict = new Dictionary<(int PersonId, int LocationId, int SubjectId), string>();
dict.Add((3, 6, 9), "ABC");
dict.Add((PersonId: 4, LocationId: 9, SubjectId: 10), "XYZ");
var personIds = dict.Keys.Select(k => k.PersonId).Distinct().ToList();

Unknown SSL protocol error in connection

I use tortoiseGit. I had the same problem. Then in push settings I unchecked "autoload putty key", tried to push, then I checked it again, and pushed, and it worked. But seriously, I don't know why.

postgresql - sql - count of `true` values

Cast the Boolean to an integer and sum.

SELECT count(*),sum(myCol::int);

You get 6,3.

Nested JSON objects - do I have to use arrays for everything?

Every object has to be named inside the parent object:

{ "data": {
    "stuff": {
        "onetype": [
            { "id": 1, "name": "" },
            { "id": 2, "name": "" }
        ],
        "othertype": [
            { "id": 2, "xyz": [-2, 0, 2], "n": "Crab Nebula", "t": 0, "c": 0, "d": 5 }
        ]
    },
    "otherstuff": {
        "thing":
            [[1, 42], [2, 2]]
    }
}
}

So you cant declare an object like this:

var obj = {property1, property2};

It has to be

var obj = {property1: 'value', property2: 'value'};

Is there a difference between "==" and "is"?

== determines if the values are equal, while is determines if they are the exact same object.

What is a unix command for deleting the first N characters of a line?

Use cut. Eg. to strip the first 4 characters of each line (i.e. start on the 5th char):

tail -f logfile | grep org.springframework | cut -c 5-

The type or namespace name 'Objects' does not exist in the namespace 'System.Data'

You need to add a reference to the .NET assembly System.Data.Linq

How to change xampp localhost to another folder ( outside xampp folder)?

Please follow @Sourav's advice.

If after restarting the server you get errors, you may need to set your directory options as well. This is done in the <Directory> tag in httpd.conf. Make sure the final config looks like this:

DocumentRoot "C:\alan"
<Directory "C:\alan">
    Options Indexes FollowSymLinks
    AllowOverride All
    Order allow,deny
    Allow from all
</Directory>

How to reload the datatable(jquery) data?

Simpler solution:

var dt = $('#table_scroll').dataTable();

$.getJSON(url, null, function (json) {
    dt.fnClearTable();
    dt.fnAddData(json.aaData);
    dt.fnDraw();
});

Best way to convert list to comma separated string in java

The Separator you are using is a UI component. You would be better using a simple String sep = ", ".

Android DialogFragment vs Dialog

Use DialogFragment over AlertDialog:


  • Since the introduction of API level 13:

    the showDialog method from Activity is deprecated. Invoking a dialog elsewhere in code is not advisable since you will have to manage the the dialog yourself (e.g. orientation change).

  • Difference DialogFragment - AlertDialog

    Are they so much different? From Android reference regarding DialogFragment:

    A DialogFragment is a fragment that displays a dialog window, floating on top of its activity's window. This fragment contains a Dialog object, which it displays as appropriate based on the fragment's state. Control of the dialog (deciding when to show, hide, dismiss it) should be done through the API here, not with direct calls on the dialog.

  • Other notes

    • Fragments are a natural evolution in the Android framework due to the diversity of devices with different screen sizes.
    • DialogFragments and Fragments are made available in the support library which makes the class usable in all current used versions of Android.

How to do IF NOT EXISTS in SQLite

How about this?

INSERT OR IGNORE INTO EVENTTYPE (EventTypeName) VALUES 'ANI Received'

(Untested as I don't have SQLite... however this link is quite descriptive.)

Additionally, this should also work:

INSERT INTO EVENTTYPE (EventTypeName)
SELECT 'ANI Received'
WHERE NOT EXISTS (SELECT 1 FROM EVENTTYPE WHERE EventTypeName = 'ANI Received');

Get current value selected in dropdown using jQuery

This is actually more efficient and has better readability in my opinion if you want to access your select with this or another variable

$('#select').find('option:selected')

In fact if I remember correctly phpStorm will attempt to auto correct the other method.

How to make a window always stay on top in .Net?

If by "going crazy" you mean that each window keeps stealing focus from the other, TopMost will not solve the problem.

Instead, try:

CalledForm.Owner = CallerForm;
CalledForm.Show();

This will show the 'child' form without it stealing focus. The child form will also stay on top of its parent even if the parent is activated or focused. This code only works easily if you've created an instance of the child form from within the owner form. Otherwise, you might have to set the owner using the API.

What is the difference between __str__ and __repr__?

__repr__ is used everywhere, except by print and str methods (when a __str__is defined !)

How to convert date to timestamp in PHP?

Using mktime:

list($day, $month, $year) = explode('-', '22-09-2008');
echo mktime(0, 0, 0, $month, $day, $year);

How to implement a Boolean search with multiple columns in pandas

the query() method can do that very intuitively. Express your condition in a string to be evaluated like the following example :

df = df.query("columnNameA <= @x or columnNameB == @y")

with x and y are declared variables which you can refer to with @

SVG gradient using CSS

Building on top of what Finesse wrote, here is a simpler way to target the svg and change it's gradient.

This is what you need to do:

  1. Assign classes to each color stop defined in the gradient element.
  2. Target the css and change the stop-color for each of those stops using plain classes.
  3. Win!

Some benefits of using classes instead of :nth-child is that it'll not be affected if you reorder your stops. Also, it makes the intent of each class clear - you'll be left wondering whether you needed a blue color on the first child or the second one.

I've tested it on all Chrome, Firefox and IE11:

_x000D_
_x000D_
.main-stop {_x000D_
  stop-color: red;_x000D_
}_x000D_
.alt-stop {_x000D_
  stop-color: green;_x000D_
}
_x000D_
<svg class="green" width="100" height="50" version="1.1" xmlns="http://www.w3.org/2000/svg">_x000D_
  <linearGradient id="gradient">_x000D_
    <stop class="main-stop" offset="0%" />_x000D_
    <stop class="alt-stop" offset="100%" />_x000D_
  </linearGradient>_x000D_
  <rect width="100" height="50" fill="url(#gradient)" />_x000D_
</svg>
_x000D_
_x000D_
_x000D_

See an editable example here: https://jsbin.com/gabuvisuhe/edit?html,css,output

Limit the height of a responsive image with css

You can use inline styling to limit the height:

<img src="" class="img-responsive" alt="" style="max-height: 400px;">

How can I replace every occurrence of a String in a file with PowerShell?

This is what I use, but it is slow on large text files.

get-content $pathToFile | % { $_ -replace $stringToReplace, $replaceWith } | set-content $pathToFile

If you are going to be replacing strings in large text files and speed is a concern, look into using System.IO.StreamReader and System.IO.StreamWriter.

try
{
   $reader = [System.IO.StreamReader] $pathToFile
   $data = $reader.ReadToEnd()
   $reader.close()
}
finally
{
   if ($reader -ne $null)
   {
       $reader.dispose()
   }
}

$data = $data -replace $stringToReplace, $replaceWith

try
{
   $writer = [System.IO.StreamWriter] $pathToFile
   $writer.write($data)
   $writer.close()
}
finally
{
   if ($writer -ne $null)
   {
       $writer.dispose()
   }
}

(The code above has not been tested.)

There is probably a more elegant way to use StreamReader and StreamWriter for replacing text in a document, but that should give you a good starting point.

Parse error: syntax error, unexpected [

Are you using php 5.4 on your local? the render line is using the new way of initializing arrays. Try replacing ["title" => "Welcome "] with array("title" => "Welcome ")

Why SQL Server throws Arithmetic overflow error converting int to data type numeric?

Lets see, numeric (3,2). That means you have 3 places for data and two of them are to the right of the decimal leaving only one to the left of the decimal. 15 has two places to the left of the decimal. BTW if you might have 100 as a value I'd increase that to numeric (5, 2)

How to remove "href" with Jquery?

If you remove the href attribute the anchor will be not focusable and it will look like simple text, but it will still be clickable.

How do I execute a MS SQL Server stored procedure in java/jsp, returning table data?

Thank to Brian for the code. I was trying to connect to the sql server with {call spname(?,?)} and I got errors, but when I change my code to exec sp... it works very well.

I post my code in hope this helps others with problems like mine:

ResultSet rs = null;
PreparedStatement cs=null;
Connection conn=getJNDIConnection();

try {
    cs=conn.prepareStatement("exec sp_name ?,?,?,?,?,?,?");
    cs.setEscapeProcessing(true);
    cs.setQueryTimeout(90);

    cs.setString(1, "valueA");

    cs.setString(2, "valueB");

    cs.setString(3, "0418");

    //commented, because no need to register parameters out!, I got results from the resultset. 
    //cs.registerOutParameter(1, Types.VARCHAR);
    //cs.registerOutParameter(2, Types.VARCHAR);

    rs = cs.executeQuery();
    ArrayList<ObjectX> listaObjectX = new ArrayList<ObjectX>();
    while (rs.next()) {

        ObjectX to = new ObjectX();
        to.setFecha(rs.getString(1));
        to.setRefId(rs.getString(2));
        to.setRefNombre(rs.getString(3));
        to.setUrl(rs.getString(4));

        listaObjectX.add(to);

    }
    return listaObjectX;
     } catch (SQLException se) {
        System.out.println("Error al ejecutar SQL"+ se.getMessage());
        se.printStackTrace();
        throw new IllegalArgumentException("Error al ejecutar SQL: " + se.getMessage());

    } finally {

        try {

            rs.close();
            cs.close();
          con.close();

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

Request Permission for Camera and Library in iOS 10 - Info.plist

Info.plist

Limited Photos

<key>PHPhotoLibraryPreventAutomaticLimitedAccessAlert</key>
<true/>

Camera

<key>NSCameraUsageDescription</key>
<string>$(PRODUCT_NAME) camera description.</string>

Photos

<key>NSPhotoLibraryUsageDescription</key>
<string>$(PRODUCT_NAME)photos description.</string>

Save Photos

<key>NSPhotoLibraryAddUsageDescription</key>
<string>$(PRODUCT_NAME) photos add description.</string>

Location

<key> NSLocationWhenInUseUsageDescription</key>
<string>$(PRODUCT_NAME) location description.</string>

Apple Music

<key>NSAppleMusicUsageDescription</key>
<string>$(PRODUCT_NAME) My description about why I need this capability</string>

Calendar

<key>NSCalendarsUsageDescription</key>
<string>$(PRODUCT_NAME) My description about why I need this capability</string>

Siri

<key>NSSiriUsageDescription</key>
<string>$(PRODUCT_NAME) My description about why I need this capability</string>

Selenium Web Driver & Java. Element is not clickable at point (x, y). Other element would receive the click

Can try with below code

 WebDriverWait wait = new WebDriverWait(driver, 30);

Pass other element would receive the click:<a class="navbar-brand" href="#"></a>

    boolean invisiable = wait.until(ExpectedConditions
            .invisibilityOfElementLocated(By.xpath("//div[@class='navbar-brand']")));

Pass clickable button id as shown below

    if (invisiable) {
        WebElement ele = driver.findElement(By.xpath("//div[@id='button']");
        ele.click();
    }

How to make VS Code to treat other file extensions as certain language?

Hold down Ctrl+Shift+P (or cmd on Mac), select "Change Language Mode" and there it is.

But I still can't find a way to make VS Code recognized files with specific extension as some certain language.

Open a webpage in the default browser

This worked perfectly for me. Since this is for personal use, I used Firefox as my browser.

 Dim url As String
    url = "http://www.google.com"
    Process.Start("Firefox", url)

Best way to initialize (empty) array in PHP

In ECMAScript implementations (for instance, ActionScript or JavaScript), Array() is a constructor function and [] is part of the array literal grammar. Both are optimized and executed in completely different ways, with the literal grammar not being dogged by the overhead of calling a function.

PHP, on the other hand, has language constructs that may look like functions but aren't treated as such. Even with PHP 5.4, which supports [] as an alternative, there is no difference in overhead because, as far as the compiler/parser is concerned, they are completely synonymous.

// Before 5.4, you could only write
$array = array(
    "foo" => "bar",
    "bar" => "foo",
);

// As of PHP 5.4, the following is synonymous with the above
$array = [
    "foo" => "bar",
    "bar" => "foo",
];

If you need to support older versions of PHP, use the former syntax. There's also an argument for readability but, being a long-time JS developer, the latter seems rather natural to me. I actually made the mistake of trying to initialise arrays using [] when I was first learning PHP.

This change to the language was originally proposed and rejected due to a majority vote against by core developers with the following reason:

This patch will not be accepted because slight majority of the core developers voted against. Though if you take a accumulated mean between core developers and userland votes seems to show the opposite it would be irresponsible to submit a patch witch is not supported or maintained in the long run.

However, it appears there was a change of heart leading up to 5.4, perhaps influenced by the implementations of support for popular databases like MongoDB (which use ECMAScript syntax).

System.Data.OracleClient requires Oracle client software version 8.1.7

Oracle Client version 11 cannot connect to 8i databases. You will need a client in version 10 at most.

What's the difference between unit tests and integration tests?

Unit test is usually done for a single functionality implemented in Software module. The scope of testing is entirely within this SW module. Unit test never fulfils the final functional requirements. It comes under whitebox testing methodology..

Whereas Integration test is done to ensure the different SW module implementations. Testing is usually carried out after module level integration is done in SW development.. This test will cover the functional requirements but not enough to ensure system validation.

Show and hide divs at a specific time interval using jQuery

Heres a another take on this problem, using recursion and without using mutable variables. Also, im not using setInterval so theres no cleanup that has to be done.

Having this HTML

<section id="testimonials">
    <h2>My testimonial spinner</h2>
    <div class="testimonial">
      <p>First content</p>
    </div>
    <div class="testimonial">
      <p>Second content</p>
    </div>
    <div class="testimonial">
       <p>Third content</p>
    </div>
</section>

Using ES2016

Here you call the function recursively and update the arguments.

  const testimonials = $('#testimonials')
      .children()
      .filter('div.testimonial');

  const showTestimonial = index => {

    testimonials.hide();
    $(testimonials[index]).fadeIn();

    return index === testimonials.length
      ? showTestimonial(0)
      : setTimeout(() => { showTestimonial(index + 1); }, 10000);
   }

showTestimonial(0); // id of the first element you want to show.

Rotating videos with FFmpeg

Rotate 90 clockwise:

ffmpeg -i in.mov -vf "transpose=1" out.mov

For the transpose parameter you can pass:

0 = 90CounterCLockwise and Vertical Flip (default)
1 = 90Clockwise
2 = 90CounterClockwise
3 = 90Clockwise and Vertical Flip

Use -vf "transpose=2,transpose=2" for 180 degrees.

Make sure you use a recent ffmpeg version from here (a static build will work fine).

Note that this will re-encode the audio and video parts. You can usually copy the audio without touching it, by using -c:a copy. To change the video quality, set the bitrate (for example with -b:v 1M) or have a look at the H.264 encoding guide if you want VBR options.

A solution is also to use this convenience script.

MySQL Select Query - Get only first 10 characters of a value

Have a look at either Left or Substring if you need to chop it up even more.

Google and the MySQL docs are a good place to start - you'll usually not get such a warm response if you've not even tried to help yourself before asking a question.

How to Test Facebook Connect Locally

You don't have to do anything difficult!

Facebook ? Settings ? Basic:
write "localhost" in the "App Domains" field then click on "+Add Platform" choose "Web Site".

After that, in the "Site Url" field write your localhost url
(e.g.: http://localhost:1337/something).

This will allow you to test your facebook plugins locally.

How do you truncate all tables in a database using TSQL?

If you want to keep data in a particular table (i.e. a static lookup table) while deleting/truncating data in other tables within the same db, then you need a loop with the exceptions in it. This is what I was looking for when I stumbled onto this question.

sp_MSForEachTable seems buggy to me (i.e. inconsistent behavior with IF statements) which is probably why its undocumented by MS.

declare @LastObjectID int = 0
declare @TableName nvarchar(100) = ''
set @LastObjectID = (select top 1 [object_id] from sys.tables where [object_id] > @LastObjectID order by [object_id])
while(@LastObjectID is not null)
begin
    set @TableName = (select top 1 [name] from sys.tables where [object_id] = @LastObjectID)

    if(@TableName not in ('Profiles', 'ClientDetails', 'Addresses', 'AgentDetails', 'ChainCodes', 'VendorDetails'))
    begin
        exec('truncate table [' + @TableName + ']')
    end 

    set @LastObjectID = (select top 1 [object_id] from sys.tables where [object_id] > @LastObjectID order by [object_id])
end

Setting the correct PATH for Eclipse

Like Abob said:

Eclipse doesn't consult the JAVA_HOME variable

You should specify where Eclipse should find your JDK in the file eclipse.ini. Specifically, the following parameter (note that it is 2 separate lines in the ini file):

-vm
C:\Java\JDK\1.8\bin\javaw.exe

or wherever your javaw.exe happens to be.

Note: The format of the ini file is very particular; make sure to consult https://wiki.eclipse.org/Eclipse.ini to ensure you get it exactly right.

Execute SQL script to create tables and rows

In the MySQL interactive client you can type:

source yourfile.sql

Alternatively you can pipe the data into mysql from the command line:

mysql < yourfile.sql

If the file doesn't specify a database then you will also need to add that:

mysql db_name < yourfile.sql

See the documentation for more details:

Center an element with "absolute" position and undefined width in CSS?

#container
{
  position: relative;
  width: 100%;
  float: left
}

#container .item
{
  width: 50%;
  position: absolute;
  margin: auto;
  left: 0;
  right: 0;
}

What is the pythonic way to detect the last element in a 'for' loop?

I like the approach of @ethan-t, but while True is dangerous from my point of view.

data_list = [1, 2, 3, 2, 1]  # sample data
L = list(data_list)  # destroy L instead of data_list
while L:
    e = L.pop(0)
    if L:
        print(f'process element {e}')
    else:
        print(f'process last element {e}')
del L

Here, data_list is so that last element is equal by value to the first one of the list. L can be exchanged with data_list but in this case it results empty after the loop. while True is also possible to use if you check that list is not empty before the processing or the check is not needed (ouch!).

data_list = [1, 2, 3, 2, 1]
if data_list:
    while True:
        e = data_list.pop(0)
        if data_list:
            print(f'process element {e}')
        else:
            print(f'process last element {e}')
            break
else:
    print('list is empty')

The good part is that it is fast. The bad - it is destructible (data_list becomes empty).

Most intuitive solution:

data_list = [1, 2, 3, 2, 1]  # sample data
for i, e in enumerate(data_list):
    if i != len(data_list) - 1:
        print(f'process element {e}')
    else:
        print(f'process last element {e}')

Oh yes, you have already proposed it!

CSS centred header image

you don't need to set the width of header in css, just put the background image as center using this code:

background: url("images/logo.png") no-repeat top center;

or you can just use img tag and put align="center" in the div

Create view with primary key?

A little late to this party - but this also works well:

CREATE VIEW [ABC].[View_SomeDataUniqueKey]
AS
SELECT 
CAST(CONCAT(CAST([ID] AS VARCHAR(4)), 
        CAST(ROW_NUMBER() OVER(ORDER BY [ID] ASC) as VARCHAR(4)) 
        )  AS int) AS [UniqueId]
,[ID]
FROM SOME_TABLE JOIN SOME_OTHER_TABLE
GO

In my case the join resulted in [ID] - the primary key being repeated up to 5 times (associated different unique data) The nice trick with this is that the original ID can be determined from each UniqueID effectively [ID]+RowNumber() = 11, 12, 13, 14, 21, 22, 23, 24 etc. If you add RowNumber() and [ID] back into the view - you can easily determine your original key from the data. But - this is not something that should be committed to a table because I am fairly sure that the RowNumber() of a view will never be reliably the same as the underlying data alters, even with the OVER(ORDER BY [ID] ASC) to try and help it.

Example output ( Select UniqueId, ID, ROWNR, Name from [REF].[View_Systems] ) :

UniqueId ID ROWNR Name 11 1 1 Amazon A 12 1 2 Amazon B 13 1 3 Amazon C 14 1 4 Amazon D 15 1 5 Amazon E

Table1:

[ID] [Name] 1 Amazon

Table2:

[ID] [Version] 1 A 1 B 1 C 1 D 1 E

CREATE VIEW [REF].[View_Systems]
AS    
SELECT 
CAST(CONCAT(CAST(TABA.[ID] AS VARCHAR(4)), 
        CAST(ROW_NUMBER() OVER(ORDER BY TABA.[ID] ASC) as VARCHAR(4)) 
        )  AS int) AS [UniqueId]
,TABA.[ID]
,ROW_NUMBER()  OVER(ORDER BY TABA.[ID] ASC) AS ROWNR
,TABA.[Name]  
FROM  [Ref].[Table1] TABA LEFT JOIN [Ref].[Table2] TABB ON TABA.[ID] = TABB.[ID]
GO

SQL: set existing column as Primary Key in MySQL

If you want to do it with phpmyadmin interface:

Select the table -> Go to structure tab -> On the row corresponding to the column you want, click on the icon with a key

Xcode5 "No matching provisioning profiles found issue" (but good at xcode4)

Sometimes, especially after generating a new certificate or starting to use a new code signing identity, there seems to be no other way to fix this, other than doing some cleaning the .pbxproj file. This is probably a bug that will be fixed, so if you are reading this long after this post, maybe you should try some other solution.

There is an excellent post about this in the pixeldock blog: http://www.pixeldock.com/blog/code-sign-error-provisioning-profile-cant-be-found/

In short, mostly quoting from that article, you need to:

  1. Make sure you have fetched all your remote iTunes Connect certificates in xcode5 from Preferences, Accounts, (select your account), View Details, press refresh button. (Normally, I answer no when xcode asks if I want to create certficate signing requests, it's not necessary when you only want to download/refresh your certificates)
  2. Close Xcode
  3. Right click on your project’s .xcodeproj bundle to show it’s contents.
  4. Open the .pbxproj file in a text editor of your choice (make a backup copy first if you feel paranoid)
  5. Find all lines in that file that include the word PROVISIONING_PROFILE and delete them.
  6. Open Xcode
  7. Enter your target and select the provisioning profile that you want to use.
  8. Build your project

Good luck!

How do I find all of the symlinks in a directory tree?

One command, no pipes

find . -type l -ls

Explanation: find from the current directory . onwards all references of -type link and list -ls those in detail. Plain and simple...

Expanding upon this answer, here are a couple more symbolic link related find commands:

Find symbolic links to a specific target

find . -lname link_target

Note that link_target is a pattern that may contain wildcard characters.

Find broken symbolic links

find -L . -type l -ls

The -L option instructs find to follow symbolic links, unless when broken.

Find & replace broken symbolic links

find -L . -type l -delete -exec ln -s new_target {} \;

More find examples

More find examples can be found here: https://hamwaves.com/find/

Get Bitmap attached to ImageView

This will get you a Bitmap from the ImageView. Though, it is not the same bitmap object that you've set. It is a new one.

imageView.buildDrawingCache();
Bitmap bitmap = imageView.getDrawingCache();

=== EDIT ===

 imageView.setDrawingCacheEnabled(true);
 imageView.measure(MeasureSpec.makeMeasureSpec(0, MeasureSpec.UNSPECIFIED), 
                   MeasureSpec.makeMeasureSpec(0, MeasureSpec.UNSPECIFIED));
 imageView.layout(0, 0, 
                  imageView.getMeasuredWidth(), imageView.getMeasuredHeight()); 
 imageView.buildDrawingCache(true);
 Bitmap bitmap = Bitmap.createBitmap(imageView.getDrawingCache());
 imageView.setDrawingCacheEnabled(false);

Pure CSS animation visibility with delay

you can't animate every property,

here's a reference to which are the animatable properties

visibility is animatable while display isn't...

in your case you could also animate opacity or height depending of the kind of effect you want to render_

fiddle with opacity animation

pg_config executable not found

Try to add it to PATH:

PATH=$PATH:/usr/pgsql-9.1/bin/ ./pip install psycopg2

How to compare Boolean?

Regarding the performance of the direct operations and the method .equals(). The .equals() methods seems to be roughly 4 times slower than ==.

I ran the following tests..

For the performance of ==:

public class BooleanPerfCheck {

    public static void main(String[] args) {
        long frameStart;
        long elapsedTime;

        boolean heyderr = false;

        frameStart = System.currentTimeMillis();

        for (int i = 0; i < 999999999; i++) {
            if (heyderr == false) {
            }
        }

        elapsedTime = System.currentTimeMillis() - frameStart;
        System.out.println(elapsedTime);
    }
}

and for the performance of .equals():

public class BooleanPerfCheck {

    public static void main(String[] args) {
        long frameStart;
        long elapsedTime;

        Boolean heyderr = false;

        frameStart = System.currentTimeMillis();

        for (int i = 0; i < 999999999; i++) {
            if (heyderr.equals(false)) {
            }
        }

        elapsedTime = System.currentTimeMillis() - frameStart;
        System.out.println(elapsedTime);
    }
}

Total system time for == was 1

Total system time for .equals() varied from 3 - 5

Thus, it is safe to say that .equals() hinders performance and that == is better to use in most cases to compare Boolean.

I can't install pyaudio on Windows? How to solve "error: Microsoft Visual C++ 14.0 is required."?

Seems PyAudio is supported by Python 2.7, 3.4, 3.5, and 3.6. Refer https://people.csail.mit.edu/hubert/pyaudio/

Please suggest if there is any alternate way to install PyAudio on Python 3.8.2

How do I find ' % ' with the LIKE operator in SQL Server?

I would use

WHERE columnName LIKE '%[%]%'

SQL Server stores string summary statistics for use in estimating the number of rows that will match a LIKE clause. The cardinality estimates can be better and lead to a more appropriate plan when the square bracket syntax is used.

The response to this Connect Item states

We do not have support for precise cardinality estimation in the presence of user defined escape characters. So we probably get a poor estimate and a poor plan. We'll consider addressing this issue in a future release.

An example

CREATE TABLE T
(
X VARCHAR(50),
Y CHAR(2000) NULL
)

CREATE NONCLUSTERED INDEX IX ON T(X)

INSERT INTO T (X)
SELECT TOP (5) '10% off'
FROM master..spt_values
UNION ALL
SELECT  TOP (100000)  'blah'
FROM master..spt_values v1,  master..spt_values v2


SET STATISTICS IO ON;
SELECT *
FROM T 
WHERE X LIKE '%[%]%'

SELECT *
FROM T
WHERE X LIKE '%\%%' ESCAPE '\'

Shows 457 logical reads for the first query and 33,335 for the second.

import sun.misc.BASE64Encoder results in error compiled in Eclipse

That error is caused by your Eclipse configuration. You can reduce it to a warning. Better still, use a Base64 encoder that isn't part of a non-public API. Apache Commons has one, or when you're already on Java 1.8, then use java.util.Base64.

Interface vs Abstract Class (general OO)

Short: Abstract classes are used for Modelling a class hierarchy of similar looking classes (For example Animal can be abstract class and Human , Lion, Tiger can be concrete derived classes)

AND

Interface is used for Communication between 2 similar / non similar classes which does not care about type of the class implementing Interface(e.g. Height can be interface property and it can be implemented by Human , Building , Tree. It does not matter if you can eat , you can swim you can die or anything.. it matters only a thing that you need to have Height (implementation in you class) ).

Should I use SVN or Git?

have you tried Bzr?

It's pretty good, connonical (the people who make Ubuntu) made it because they didn't like anything else on the market...

Split string by single spaces

If you are averse to boost, you can use regular old operator>>, along with std::noskipws:

EDIT: updates after testing.

#include <iostream>
#include <iomanip>
#include <vector>
#include <string>
#include <algorithm>
#include <iterator>
#include <sstream>

void split(const std::string& str, std::vector<std::string>& v) {
  std::stringstream ss(str);
  ss >> std::noskipws;
  std::string field;
  char ws_delim;
  while(1) {
    if( ss >> field )
      v.push_back(field);
    else if (ss.eof())
      break;
    else
      v.push_back(std::string());
    ss.clear();
    ss >> ws_delim;
  }
}

int main() {
  std::vector<std::string> v;
  split("hello world  how are   you", v);
  std::copy(v.begin(), v.end(), std::ostream_iterator<std::string>(std::cout, "-"));
  std::cout << "\n";
}

http://ideone.com/62McC

Set object property using reflection

You can also access fields using a simillar manner:

var obj=new MyObject();
FieldInfo fi = obj.GetType().
  GetField("Name", BindingFlags.NonPublic | BindingFlags.Instance);
fi.SetValue(obj,value)

With reflection everything can be an open book:) In my example we are binding to a private instance level field.

Removing underline with href attribute

Add a style with the attribute text-decoration:none;:

There are a number of different ways of doing this.

Inline style:

<a href="xxx.html" style="text-decoration:none;">goto this link</a>

Inline stylesheet:

<html>
<head>
<style type="text/css">
   a {
      text-decoration:none;
   }
</style>
</head>
<body>
<a href="xxx.html">goto this link</a>
</body>
</html>

External stylesheet:

<html>
<head>
<link rel="Stylesheet" href="stylesheet.css" />
</head>
<body>
<a href="xxx.html">goto this link</a>
</body>
</html>

stylesheet.css:

a {
      text-decoration:none;
   }

Get Android .apk file VersionName or VersionCode WITHOUT installing apk

    EditText ET1 = (EditText) findViewById(R.id.editText1);

    PackageInfo pinfo;
    try {
        pinfo = getPackageManager().getPackageInfo(getPackageName(), 0);
        String versionName = pinfo.versionName;
        ET1.setText(versionName);
        //ET2.setText(versionNumber);
    } catch (NameNotFoundException e) {
        // TODO Auto-generated catch block
        e.printStackTrace();
    }

Is it possible to make Font Awesome icons larger than 'fa-5x'?

You can also define a scale transformation, with CSS like so:

.larger-icon {
 transform:scale(2);
}

Calling a phone number in swift

Swift 5: iOS >= 10.0

Only works on physical device.

private func callNumber(phoneNumber: String) {
    guard let url = URL(string: "telprompt://\(phoneNumber)"),
        UIApplication.shared.canOpenURL(url) else {
        return
    }
    UIApplication.shared.open(url, options: [:], completionHandler: nil)
}

Laravel - Session store not set on request

In my case I added the following 4 lines to $middlewareGroups (in app/Http/Kernel.php):

'api' => [
    \App\Http\Middleware\EncryptCookies::class,
    \Illuminate\Cookie\Middleware\AddQueuedCookiesToResponse::class,
    \Illuminate\Session\Middleware\StartSession::class,
    \App\Http\Middleware\VerifyCsrfToken::class,
    'throttle:60,1',
    'bindings',
],

IMPORTANT: The 4 new lines must be added BEFORE 'throttle' and 'bindings'!

Otherwise a "CSRF token not match" error will rise. I've struggled in this for several hours just to find the order is important.

This allowed me to access session in my API. I also added VerifyCsrfToken as when cookies/sessions are involved, CSRF needs to be taken care of.

check if a number already exist in a list in python

If you want to have unique elements in your list, then why not use a set, if of course, order does not matter for you: -

>>> s = set()
>>> s.add(2)
>>> s.add(4)
>>> s.add(5)
>>> s.add(2)
>>> s
39: set([2, 4, 5])

If order is a matter of concern, then you can use: -

>>> def addUnique(l, num):
...     if num not in l:
...         l.append(num)
...     
...     return l

You can also find an OrderedSet recipe, which is referred to in Python Documentation

How to condense if/else into one line in Python?

An example of Python's way of doing "ternary" expressions:

i = 5 if a > 7 else 0

translates into

if a > 7:
   i = 5
else:
   i = 0

This actually comes in handy when using list comprehensions, or sometimes in return statements, otherwise I'm not sure it helps that much in creating readable code.

The readability issue was discussed at length in this recent SO question better way than using if-else statement in python.

It also contains various other clever (and somewhat obfuscated) ways to accomplish the same task. It's worth a read just based on those posts.

"replace" function examples

Be aware that the third parameter (value) in the examples given above: the value is a constant (e.g. 'Z' or c(20,30)).

Defining the third parameter using values from the data frame itself can lead to confusion.

E.g. with a simple data frame such as this (using dplyr::data_frame):

tmp <- data_frame(a=1:10, b=sample(LETTERS[24:26], 10, replace=T))

This will create somthing like this:

       a     b
   (int) (chr)
1      1     X
2      2     Y
3      3     Y
4      4     X
5      5     Z

..etc

Now suppose you want wanted to do, was to multiply the values in column 'a' by 2, but only where column 'b' is "X". My immediate thought would be something like this:

with(tmp, replace(a, b=="X", a*2))

That will not provide the desired outcome, however. The a*2 will defined as a fixed vector rather than a reference to the 'a' column. The vector 'a*2' will thus be

[1]  2  4  6  8 10 12 14 16 18 20

at the start of the 'replace' operation. Thus, the first row where 'b' equals "X", the value in 'a' will be placed by 2. The second time, it will be replaced by 4, etc ... it will not be replaced by two-times-the-value-of-a in that particular row.

Can I have a video with transparent background using HTML5 video tag?

I struggled with this, too. Here's what I found. Expanding on Adam's answer, here's a bit more detail, including how to encode VP9 with alpha in a Webm container.

First, Here's a CodePen playground you can play with, feel free to use my videos for testing.

        <video width="600" height="100%" autoplay loop muted playsinline>
        <source src="https://rotato.netlify.app/alpha-demo/movie-hevc.mov" type='video/mp4'; codecs="hvc1">
        <source src="https://rotato.netlify.app/alpha-demo/movie-webm.webm" type="video/webm">
        </video>

And here's a full demo page using z-index to layer the transparent video on top and below certain elements. (You can clone the Webflow template) enter image description here

So, we'll need a Webm movie for Chrome, and an HEVC with Alpha (supported by Safari on all platforms since 2019)

Which browsers are supported?

For Chrome, I've tested successfully on version 30 from 2013. (Caniuse webm doesn't seem to say which webm codec is supported, so I had to try my way). Earlier versions of chrome seem to render a black area.

For Safari, it's simpler: Catalina (2019) or iOS 11 (2019)

Encoding

Depending on which editing app you're using, I recommend exporting the HEVC with Alpha directly.

But many apps don't support the Webm format, especially on Mac, since it's not a part of AVFoundation.

I recommend exporting an intermediate format like ProRes4444 with an alpha channel to not lose too much quality at this step. Once you have that file, making your webm is as simple as

ffmpeg -i "your-movie-in-prores.mov" -c:v libvpx-vp9 movie-webm.webm

See more approaches in this blog post.

How to check type of variable in Java?

Just use:

.getClass().getSimpleName();

Example:

StringBuilder randSB = new StringBuilder("just a String");
System.out.println(randSB.getClass().getSimpleName());

Output:

StringBuilder

removing bold styling from part of a header

If you don't want a separate CSS file, you can use inline CSS:

<h1>This text should be bold, <span style="font-weight:normal">but this text should not</span></h1>

However, as Madara's comment suggests, you might want to consider putting the unbolded part in a different header, depending on the use case involved.

Android: How to rotate a bitmap on a center point

matrix.reset();
matrix.setTranslate( anchor.x, anchor.y );
matrix.postRotate((float) rotation , 0,0);
matrix.postTranslate(positionOfAnchor.x, positionOfAnchor.x);
c.drawBitmap(bitmap, matrix, null); 

'npm' is not recognized as internal or external command, operable program or batch file

To elaborate on Breno's answer... For Windows 7 these steps worked for me:

  1. Open the Control Panel (Click the Start button, then click Control Panel)
  2. Click User Accounts
  3. Click Change my environment variables
  4. Select PATH and click the Edit... button
  5. At the end of the Variable value, add ;C:\Program Files\nodejs
  6. Click Ok on the "Edit User Variable" window, then click Ok on the "Environment Variables" window
  7. Start a command prompt window (Start button, then type cmd into the search and hit enter)
  8. At the prompt (C:\>) type npm and hit enter; you should now see some help text (Usage: npm <command> etc.) rather than "npm is not recognized..."

Now you can start using npm!

How can I remove a substring from a given String?

If you know the start and end index you may use this

string = string.substring(0, start_index) + string.substring(end_index, string.length());

Interface defining a constructor signature?

One way to solve this problem i found is to seperate out the construction into a seperate factory. For example I have an abstract class called IQueueItem, and I need a way to translate that object to and from another object (CloudQueueMessage). So on the interface IQueueItem i have -

public interface IQueueItem
{
    CloudQueueMessage ToMessage();
}

Now, I also need a way for my actual queue class to translate a CloudQueueMessage back to a IQueueItem - ie the need for a static construction like IQueueItem objMessage = ItemType.FromMessage. Instead I defined another interface IQueueFactory -

public interface IQueueItemFactory<T> where T : IQueueItem
{
    T FromMessage(CloudQueueMessage objMessage);
}

Now I can finally write my generic queue class without the new() constraint which in my case was the main issue.

public class AzureQueue<T> where T : IQueueItem
{
    private IQueueItemFactory<T> _objFactory;
    public AzureQueue(IQueueItemFactory<T> objItemFactory)
    {
        _objFactory = objItemFactory;
    }


    public T GetNextItem(TimeSpan tsLease)
    {
        CloudQueueMessage objQueueMessage = _objQueue.GetMessage(tsLease);
        T objItem = _objFactory.FromMessage(objQueueMessage);
        return objItem;
    }
}

now I can create an instance that satisfies the criteria for me

 AzureQueue<Job> objJobQueue = new JobQueue(new JobItemFactory())

hopefully this helps someone else out someday, obviously a lot of internal code removed to try to show the problem and solution

React Router with optional path parameter

The edit you posted was valid for an older version of React-router (v0.13) and doesn't work anymore.


React Router v1, v2 and v3

Since version 1.0.0 you define optional parameters with:

<Route path="to/page(/:pathParam)" component={MyPage} />

and for multiple optional parameters:

<Route path="to/page(/:pathParam1)(/:pathParam2)" component={MyPage} />

You use parenthesis ( ) to wrap the optional parts of route, including the leading slash (/). Check out the Route Matching Guide page of the official documentation.

Note: The :paramName parameter matches a URL segment up to the next /, ?, or #. For more about paths and params specifically, read more here.


React Router v4 and above

React Router v4 is fundamentally different than v1-v3, and optional path parameters aren't explicitly defined in the official documentation either.

Instead, you are instructed to define a path parameter that path-to-regexp understands. This allows for much greater flexibility in defining your paths, such as repeating patterns, wildcards, etc. So to define a parameter as optional you add a trailing question-mark (?).

As such, to define an optional parameter, you do:

<Route path="/to/page/:pathParam?" component={MyPage} />

and for multiple optional parameters:

<Route path="/to/page/:pathParam1?/:pathParam2?" component={MyPage} />

Note: React Router v4 is incompatible with (read more here). Use version v3 or earlier (v2 recommended) instead.

MySQL Error 1264: out of range value for column

Work with:

ALTER TABLE `table` CHANGE `cust_fax` `cust_fax` VARCHAR(60) NULL DEFAULT NULL; 

How to sort a HashSet?

We can not decide that the elements of a HashSet would be sorted automatically. But we can sort them by converting into TreeSet or any List like ArrayList or LinkedList etc.

// Create a TreeSet object of class E
TreeSet<E> ts = new TreeSet<E> ();

// Convert your HashSet into TreeSet
ts.addAll(yourHashSet);

System.out.println(ts.toString() + "\t Sorted Automatically");

What properties does @Column columnDefinition make redundant?

My Answer: All of the following should be overridden (i.e. describe them all within columndefinition, if appropriate):

  • length
  • precision
  • scale
  • nullable
  • unique

i.e. the column DDL will consist of: name + columndefinition and nothing else.

Rationale follows.


  1. Annotation containing the word "Column" or "Table" is purely physical - properties only used to control DDL/DML against database.

  2. Other annotation purely logical - properties used in-memory in java to control JPA processing.

  3. That's why sometimes it appears the optionality/nullability is set twice - once via @Basic(...,optional=true) and once via @Column(...,nullable=true). Former says attribute/association can be null in the JPA object model (in-memory), at flush time; latter says DB column can be null. Usually you'd want them set the same - but not always, depending on how the DB tables are setup and reused.

In your example, length and nullable properties are overridden and redundant.


So, when specifying columnDefinition, what other properties of @Column are made redundant?

  1. In JPA Spec & javadoc:

    • columnDefinition definition: The SQL fragment that is used when generating the DDL for the column.

    • columnDefinition default: Generated SQL to create a column of the inferred type.

    • The following examples are provided:

      @Column(name="DESC", columnDefinition="CLOB NOT NULL", table="EMP_DETAIL")
      @Column(name="EMP_PIC", columnDefinition="BLOB NOT NULL")
      
    • And, err..., that's it really. :-$ ?!

    Does columnDefinition override other properties provided in the same annotation?

    The javadoc and JPA spec don't explicity address this - spec's not giving great protection. To be 100% sure, test with your chosen implementation.

  2. The following can be safely implied from examples provided in the JPA spec

    • name & table can be used in conjunction with columnDefinition, neither are overridden
    • nullable is overridden/made redundant by columnDefinition
  3. The following can be fairly safely implied from the "logic of the situation" (did I just say that?? :-P ):

    • length, precision, scale are overridden/made redundant by the columnDefinition - they are integral to the type
    • insertable and updateable are provided separately and never included in columnDefinition, because they control SQL generation in-memory, before it is emmitted to the database.
  4. That leaves just the "unique" property. It's similar to nullable - extends/qualifies the type definition, so should be treated integral to type definition. i.e. should be overridden.


Test My Answer For columns "A" & "B", respectively:

  @Column(name="...", table="...", insertable=true, updateable=false,
          columndefinition="NUMBER(5,2) NOT NULL UNIQUE"

  @Column(name="...", table="...", insertable=false, updateable=true,
          columndefinition="NVARCHAR2(100) NULL"
  • confirm generated table has correct type/nullability/uniqueness
  • optionally, do JPA insert & update: former should include column A, latter column B

Could not connect to SMTP host: smtp.gmail.com, port: 465, response: -1

I have been experiencing this issue when debugging using NetBeans, even executing the actual jar file. Antivirus would block sending email. You should temporarily disable your antivirus during debugging or exclude NetBeans and the actual jar file from being scanned. In my case, I'm using Avast.

See this link on how to Exclude : How to Add File/Website Exception into avast! Antivirus 2014

It works for me.

WPF What is the correct way of using SVG files as icons in WPF

Install the SharpVectors library

Install-Package SharpVectors

Add the following in XAML

<UserControl xmlns:svgc="http://sharpvectors.codeplex.com/svgc">
    <svgc:SvgViewbox Source="/Icons/icon.svg"/>
</UserControl>

How to get the current directory of the cmdlet being executed

You would think that using '.\' as the path means that it's the invocation path. But not all the time. Example, if you use it inside a job ScriptBlock. In which case, it might point to %profile%\Documents.

How to declare a local variable in Razor?

I think you were pretty close, try this:

@{bool isUserConnected = string.IsNullOrEmpty(Model.CreatorFullName);}
@if (isUserConnected)
{ // meaning that the viewing user has not been saved so continue
    <div>
        <div> click to join us </div>
        <a id="login" href="javascript:void(0);" style="display: inline; ">join here</a>
    </div>
}

Random number from a range in a Bash Script

The simplest general way that comes to mind is a perl one-liner:

perl -e 'print int(rand(65000-2000)) + 2000'

You could always just use two numbers:

PORT=$(($RANDOM + ($RANDOM % 2) * 32768))

You still have to clip to your range. It's not a general n-bit random number method, but it'll work for your case, and it's all inside bash.

If you want to be really cute and read from /dev/urandom, you could do this:

od -A n -N 2 -t u2 /dev/urandom

That'll read two bytes and print them as an unsigned int; you still have to do your clipping.

How to enable MySQL Query Log?

On Windows you can simply go to

C:\wamp\bin\mysql\mysql5.1.53\my.ini

Insert this line in my.ini

general_log_file = c:/wamp/logs/mysql_query_log.log

The my.ini file finally looks like this

...
...
...    
socket      = /tmp/mysql.sock
skip-locking
key_buffer = 16M
max_allowed_packet = 1M
table_cache = 64
sort_buffer_size = 512K
net_buffer_length = 8K
read_buffer_size = 256K
read_rnd_buffer_size = 512K
myisam_sort_buffer_size = 8M
basedir=c:/wamp/bin/mysql/mysql5.1.53
log = c:/wamp/logs/mysql_query_log.log        #dump query logs in this file
log-error=c:/wamp/logs/mysql.log
datadir=c:/wamp/bin/mysql/mysql5.1.53/data
...
...
...
...

How to find and replace all occurrences of a string recursively in a directory tree?

I know this is a really old question, but...

  1. @vehomzzz's answer uses find and xargs when the questions says explicitly grep and sed only.

  2. @EmployedRussian and @BrooksMoses tried to say it was a dup of awk and sed, but it's not - again, the question explicitly says grep and sed only.

So here is my solution, assuming you are using Bash as your shell:

OLDIFS=$IFS
IFS=$'\n'
for f in `grep -rl a.example.com .` # Use -irl instead of -rl for case insensitive search
do
    sed -i 's/a\.example\.com/b.example.com/g' $f # Use /gi instead of /g for case insensitive search
done
IFS=$OLDIFS

If you are using a different shell, such as Unix SHell, let me know and I will try to find a syntax adjustment.

P.S.: Here's a one-liner:

OLDIFS=$IFS;IFS=$'\n';for f in `grep -rl a.example.com .`;do sed -i 's/a\.example\.com/b.example.com/g' $f;done;IFS=$OLDIFS

Sources:

How do you set the max number of characters for an EditText in Android?

Dynamically:

editText.setFilters(new InputFilter[] { new InputFilter.LengthFilter(MAX_NUM) });

Via xml:

<EditText
    android:maxLength="@integer/max_edittext_length"

How to present popover properly in iOS 8

my two cents for xcode 9.1 / swift 4.

class ViewController: UIViewController, UIPopoverPresentationControllerDelegate {

    override func viewDidLoad(){
        super.viewDidLoad()

        let when = DispatchTime.now() + 0.5

        DispatchQueue.main.asyncAfter(deadline: when, execute: { () -> Void in
            // to test after 05.secs... :)
            self.showPopover(base: self.view)

        })

}


func showPopover(base: UIView) {
    if let viewController = self.storyboard?.instantiateViewController(withIdentifier: "popover") as? PopOverViewController {

        let navController = UINavigationController(rootViewController: viewController)
        navController.modalPresentationStyle = .popover

        if let pctrl = navController.popoverPresentationController {
            pctrl.delegate = self

            pctrl.sourceView = base
            pctrl.sourceRect = base.bounds

            self.present(navController, animated: true, completion: nil)
        }
    }
}


@IBAction func onShow(sender: UIButton){
    self.showPopover(base: sender)
}

func adaptivePresentationStyle(for controller: UIPresentationController, traitCollection: UITraitCollection) -> UIModalPresentationStyle{
    return .none
}

and experiment in:

func adaptivePresentationStyle...

    return .popover

or: return .pageSheet.... and so on..

nginx - nginx: [emerg] bind() to [::]:80 failed (98: Address already in use)

I had the same problem in letsencrypt (certbot) and nginx,

ref: https://github.com/certbot/certbot/issues/5486

this error does not have a solution yet

so, a changed a cron for renew (putting a reload after renew) (using suggest from certbot)

-- in /etc/cron.d/certbot
from
0 */12 * * * root test -x /usr/bin/certbot -a \! -d /run/systemd/system && perl -e 'sleep int(rand(3600))' && certbot -q renew 
to
0 */12 * * * root test -x /usr/bin/certbot -a \! -d /run/systemd/system && perl -e 'sleep int(rand(3600))' && certbot -q renew --pre-hook "service nginx stop" --post-hook "service nginx start"

logs (short):

-- in /var/log/syslog
Jun 10 00:14:25 localhost systemd[1]: Starting Certbot...
Jun 10 00:14:38 localhost certbot[22222]: nginx: [error] open() "/run/nginx.pid$
Jun 10 00:14:41 localhost certbot[22222]: Hook command "nginx" returned error c$
Jun 10 00:14:41 localhost certbot[22222]: Error output from nginx:
Jun 10 00:14:41 localhost certbot[22222]: nginx: [emerg] bind() to 0.0.0.0:443 $
Jun 10 00:14:41 localhost certbot[22222]: nginx: [emerg] bind() to 0.0.0.0:80 f$
Jun 10 00:14:41 localhost certbot[22222]: nginx: [emerg] bind() to 0.0.0.0:443 $
Jun 10 00:14:41 localhost certbot[22222]: nginx: [emerg] bind() to 0.0.0.0:80 f$
Jun 10 00:14:41 localhost certbot[22222]: nginx: [emerg] bind() to 0.0.0.0:443 $
Jun 10 00:14:41 localhost certbot[22222]: nginx: [emerg] bind() to 0.0.0.0:80 f$
Jun 10 00:14:41 localhost certbot[22222]: nginx: [emerg] bind() to 0.0.0.0:443 $
Jun 10 00:14:41 localhost certbot[22222]: nginx: [emerg] bind() to 0.0.0.0:80 f$
Jun 10 00:14:41 localhost certbot[22222]: nginx: [emerg] bind() to 0.0.0.0:443 $
Jun 10 00:14:41 localhost certbot[22222]: nginx: [emerg] bind() to 0.0.0.0:80 f$
Jun 10 00:14:41 localhost certbot[22222]: nginx: [emerg] still could not bind()
Jun 10 00:14:41 localhost systemd[1]: Started Certbot.


-- in /var/log/nginx/error.log
2018/06/10 00:14:27 [notice] 22233#22233: signal process started
2018/06/10 00:14:31 [notice] 22237#22237: signal process started
2018/06/10 00:14:33 [notice] 22240#22240: signal process started
2018/06/10 00:14:34 [notice] 22245#22245: signal process started
2018/06/10 00:14:38 [notice] 22255#22255: signal process started
2018/06/10 00:14:38 [error] 22255#22255: open() "/run/nginx.pid" failed (2: No $
2018/06/10 00:14:39 [emerg] 22261#22261: bind() to 0.0.0.0:443 failed (98: Addr$
2018/06/10 00:14:39 [emerg] 22261#22261: bind() to 0.0.0.0:80 failed (98: Addre$
2018/06/10 00:14:39 [emerg] 22261#22261: bind() to 0.0.0.0:443 failed (98: Addr$
2018/06/10 00:14:39 [emerg] 22261#22261: bind() to 0.0.0.0:80 failed (98: Addre$
2018/06/10 00:14:39 [emerg] 22261#22261: bind() to 0.0.0.0:443 failed (98: Addr$
2018/06/10 00:14:39 [emerg] 22261#22261: bind() to 0.0.0.0:80 failed (98: Addre$
2018/06/10 00:14:39 [emerg] 22261#22261: bind() to 0.0.0.0:443 failed (98: Addr$
2018/06/10 00:14:39 [emerg] 22261#22261: bind() to 0.0.0.0:80 failed (98: Addre$
2018/06/10 00:14:39 [emerg] 22261#22261: bind() to 0.0.0.0:443 failed (98: Addr$
2018/06/10 00:14:39 [emerg] 22261#22261: bind() to 0.0.0.0:80 failed (98: Addre$
2018/06/10 00:14:39 [emerg] 22261#22261: still could not bind()

JavaScript "cannot read property "bar" of undefined

Compound checking:

   if (thing.foo && thing.foo.bar) {
      ... thing.foor.bar exists;
   }

Check if string matches pattern

Please try the following:

import re

name = ["A1B1", "djdd", "B2C4", "C2H2", "jdoi","1A4V"]

# Match names.
for element in name:
     m = re.match("(^[A-Z]\d[A-Z]\d)", element)
     if m:
        print(m.groups())

Save current directory in variable using Bash?

This saves the absolute path of the current working directory to the variable cwd:

cwd=$(pwd)

In your case you can just do:

export PATH=$PATH:$(pwd)+somethingelse

How can I generate a 6 digit unique number?

You can use $uniq = round(microtime(true));

it generates 10 digit base on time which is never be duplicated

C++ preprocessor __VA_ARGS__ number of arguments

This is actually compiler dependent, and not supported by any standard.

Here however you have a macro implementation that does the count:

#define PP_NARG(...) \
         PP_NARG_(__VA_ARGS__,PP_RSEQ_N())
#define PP_NARG_(...) \
         PP_ARG_N(__VA_ARGS__)
#define PP_ARG_N( \
          _1, _2, _3, _4, _5, _6, _7, _8, _9,_10, \
         _11,_12,_13,_14,_15,_16,_17,_18,_19,_20, \
         _21,_22,_23,_24,_25,_26,_27,_28,_29,_30, \
         _31,_32,_33,_34,_35,_36,_37,_38,_39,_40, \
         _41,_42,_43,_44,_45,_46,_47,_48,_49,_50, \
         _51,_52,_53,_54,_55,_56,_57,_58,_59,_60, \
         _61,_62,_63,N,...) N
#define PP_RSEQ_N() \
         63,62,61,60,                   \
         59,58,57,56,55,54,53,52,51,50, \
         49,48,47,46,45,44,43,42,41,40, \
         39,38,37,36,35,34,33,32,31,30, \
         29,28,27,26,25,24,23,22,21,20, \
         19,18,17,16,15,14,13,12,11,10, \
         9,8,7,6,5,4,3,2,1,0

/* Some test cases */


PP_NARG(A) -> 1
PP_NARG(A,B) -> 2
PP_NARG(A,B,C) -> 3
PP_NARG(A,B,C,D) -> 4
PP_NARG(A,B,C,D,E) -> 5
PP_NARG(1,2,3,4,5,6,7,8,9,0,
         1,2,3,4,5,6,7,8,9,0,
         1,2,3,4,5,6,7,8,9,0,
         1,2,3,4,5,6,7,8,9,0,
         1,2,3,4,5,6,7,8,9,0,
         1,2,3,4,5,6,7,8,9,0,
         1,2,3) -> 63

Load a Bootstrap popover content with AJAX. Is this possible?

The solution of Çagatay Gürtürk is nice but I experienced the same weirdness described by Luke The Obscure:

When ajax loading lasts too much (or mouse events are too quick) we have a .popover('show') and no .popover('hide') on a given element causing the popover to remain open.

I preferred this massive-pre-load solution, all popover-contents are loaded and events are handled by bootstrap like in normal (static) popovers.

$('.popover-ajax').each(function(index){

    var el=$(this);

    $.get(el.attr('data-load'),function(d){
        el.popover({content: d});       
    });     

});

Best way to get application folder path

Note that not all of these methods will return the same value. In some cases, they can return the same value, but be careful, their purposes are different:

Application.StartupPath

returns the StartupPath parameter (can be set when run the application)

System.IO.Directory.GetCurrentDirectory()

returns the current directory, which may or may not be the folder where the application is located. The same goes for Environment.CurrentDirectory. In case you are using this in a DLL file, it will return the path of where the process is running (this is especially true in ASP.NET).

Unresolved Import Issues with PyDev and Eclipse

I am using eclipse kepler 4.3, PyDev 3.9.2 and on my ubuntu 14.04 I encountered with the same problem. I tried and spent hours, with all the above most of the options but in vain. Then I tried the following which was great:

  • Select Project-> RightClick-> PyDev-> Remove PyDev Project Config
  • file-> restart

And I was using Python 2.7 as an interpreter, although it doesn’t effect, I think.

Merge data frames based on rownames in R

See ?merge:

the name "row.names" or the number 0 specifies the row names.

Example:

R> de <- merge(d, e, by=0, all=TRUE)  # merge by row names (by=0 or by="row.names")
R> de[is.na(de)] <- 0                 # replace NA values
R> de
  Row.names   a   b   c   d   e   f   g   h   i  j  k  l  m  n  o  p  q  r  s
1         1 1.0 2.0 3.0 4.0 5.0 6.0 7.0 8.0 9.0 10 11 12 13 14 15 16 17 18 19
2         2 0.1 0.2 0.3 0.4 0.5 0.6 0.7 0.8 0.9  1  0  0  0  0  0  0  0  0  0
3         3 0.0 0.0 0.0 0.0 0.0 0.0 0.0 0.0 0.0  0 21 22 23 24 25 26 27 28 29
   t
1 20
2  0
3 30

Setting property 'source' to 'org.eclipse.jst.jee.server:JSFTut' did not find a matching property

I thought I'd add that for Tomcat 7.x, <Context> is not in the server.xml, but in the context.xml. Removing and re-adding the project did not seem to help my similar issue, which was a web.xml issue, which I found out by checking the context.xml which had this line in the <Context> section:

<WatchedResource>WEB-INF/web.xml</WatchedResource>

The solution in WARNING: Setting property 'source' to 'org.eclipse.jst.jee.server:appname' did not find a matching property brought me closer to my answer, as the change of publishing into a separate XML did resolve the error reported above for me, but unfortunately it generated a second error that I'm still investigating.

WARNING: [SetContextPropertiesRule]{Context} Setting property 'source' to 'org.eclipse.jst.jee.server:myproject' did not find a matching property.

What is the use of DesiredCapabilities in Selenium WebDriver?

When you run selenium WebDriver, the WebDriver opens a remote server in your computer's local host. Now, this server, called the Selenium Server, is used to interpret your code into actions to run or "drive" the instance of a real browser known as either chromebrowser, ie broser, ff browser, etc.

So, the Selenium Server can interact with different browser properties and hence it has many "capabilities".

Now what capabilities do you desire? Consider a scenario where you are validating if files have been downloaded properly in your app but, however, you do not have a desktop automation tool. In the case where you click the download link and a desktop pop up shows up to ask where to save and/or if you want to download. Your next route to bypass that would be to suppress that pop up. How? Desired Capabilities.

There are other such examples. In summary, Selenium Server can do a lot, use Desired Capabilities to tailor it to your need.

Trying to get property of non-object in

<?php foreach ($sidemenus->mname as $sidemenu): ?>
<?php echo $sidemenu ."<br />";?>

or

$sidemenus = mysql_fetch_array($results);

then

<?php echo $sidemenu['mname']."<br />";?>

how to create Socket connection in Android?

Here, in this post you will find the detailed code for establishing socket between devices or between two application in the same mobile.

You have to create two application to test below code.

In both application's manifest file, add below permission

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

1st App code: Client Socket

activity_main.xml

<?xml version="1.0" encoding="utf-8"?>

<RelativeLayout xmlns:android="http://schemas.android.com/apk/res/android"
    android:layout_width="match_parent"
    android:layout_height="match_parent">

    <TableRow
        android:id="@+id/tr_send_message"
        android:layout_width="match_parent"
        android:layout_height="wrap_content"
        android:gravity="center"
        android:layout_alignParentLeft="true"
        android:layout_alignParentStart="true"
        android:layout_alignParentTop="true"
        android:layout_marginTop="11dp">

        <EditText
            android:id="@+id/edt_send_message"
            android:layout_width="0dp"
            android:layout_height="wrap_content"
            android:layout_weight="1"
            android:layout_marginRight="10dp"
            android:layout_marginLeft="10dp"
            android:hint="Enter message"
            android:inputType="text" />

        <Button
            android:id="@+id/btn_send"
            android:layout_width="wrap_content"
            android:layout_height="wrap_content"
            android:layout_marginRight="10dp"
            android:text="Send" />
    </TableRow>

    <ScrollView
        android:layout_width="match_parent"
        android:layout_height="match_parent"
        android:layout_alignParentLeft="true"
        android:layout_alignParentStart="true"
        android:layout_below="@+id/tr_send_message"
        android:layout_marginTop="25dp"
        android:id="@+id/scrollView2">

        <TextView
            android:id="@+id/tv_reply_from_server"
            android:layout_width="match_parent"
            android:layout_height="wrap_content"
            android:orientation="vertical" />
    </ScrollView>
</RelativeLayout>

MainActivity.java

import android.os.Bundle;
import android.os.Handler;
import android.support.v7.app.AppCompatActivity;
import android.view.View;
import android.widget.Button;
import android.widget.EditText;
import android.widget.TextView;

import java.io.BufferedReader;
import java.io.IOException;
import java.io.InputStreamReader;
import java.io.OutputStream;
import java.io.PrintWriter;
import java.net.Socket;

/**
 * Created by Girish Bhalerao on 5/4/2017.
 */
public class MainActivity extends AppCompatActivity implements View.OnClickListener {

    private TextView mTextViewReplyFromServer;
    private EditText mEditTextSendMessage;

    @Override
    protected void onCreate(Bundle savedInstanceState) {
        super.onCreate(savedInstanceState);
        setContentView(R.layout.activity_main);

        Button buttonSend = (Button) findViewById(R.id.btn_send);

        mEditTextSendMessage = (EditText) findViewById(R.id.edt_send_message);
        mTextViewReplyFromServer = (TextView) findViewById(R.id.tv_reply_from_server);

        buttonSend.setOnClickListener(this);
    }

    @Override
    public void onClick(View v) {

        switch (v.getId()) {

            case R.id.btn_send:
                sendMessage(mEditTextSendMessage.getText().toString());
                break;
        }
    }

    private void sendMessage(final String msg) {

        final Handler handler = new Handler();
        Thread thread = new Thread(new Runnable() {
            @Override
            public void run() {

                try {
                    //Replace below IP with the IP of that device in which server socket open.
                    //If you change port then change the port number in the server side code also.
                    Socket s = new Socket("xxx.xxx.xxx.xxx", 9002);

                    OutputStream out = s.getOutputStream();

                    PrintWriter output = new PrintWriter(out);

                    output.println(msg);
                    output.flush();
                    BufferedReader input = new BufferedReader(new InputStreamReader(s.getInputStream()));
                    final String st = input.readLine();

                    handler.post(new Runnable() {
                        @Override
                        public void run() {

                            String s = mTextViewReplyFromServer.getText().toString();
                            if (st.trim().length() != 0)
                                mTextViewReplyFromServer.setText(s + "\nFrom Server : " + st);
                        }
                    });

                    output.close();
                    out.close();
                    s.close();
                } catch (IOException e) {
                    e.printStackTrace();
                }
            }
        });

        thread.start();
    }
}

2nd App Code - Server Socket

activity_main.xml

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

    <Button
        android:id="@+id/btn_stop_receiving"
        android:layout_width="wrap_content"
        android:layout_height="wrap_content"
        android:text="STOP Receiving data"
        android:layout_alignParentTop="true"
        android:enabled="false"
        android:layout_centerHorizontal="true"
        android:layout_marginTop="89dp" />

    <ScrollView
        android:layout_width="match_parent"
        android:layout_height="match_parent"
        android:layout_below="@+id/btn_stop_receiving"
        android:layout_marginTop="35dp"
        android:layout_alignParentLeft="true"
        android:layout_alignParentStart="true">

        <TextView
            android:id="@+id/tv_data_from_client"
            android:layout_width="match_parent"
            android:layout_height="wrap_content"
            android:orientation="vertical" />
    </ScrollView>

    <Button
        android:id="@+id/btn_start_receiving"
        android:layout_width="wrap_content"
        android:layout_height="wrap_content"
        android:text="START Receiving data"
        android:layout_alignParentTop="true"
        android:layout_centerHorizontal="true"
        android:layout_marginTop="14dp" />
</RelativeLayout>

MainActivity.java

import android.os.Bundle;
import android.os.Handler;
import android.support.v7.app.AppCompatActivity;
import android.view.View;
import android.widget.Button;
import android.widget.TextView;

import java.io.BufferedReader;
import java.io.IOException;
import java.io.InputStreamReader;
import java.io.PrintWriter;
import java.net.ServerSocket;
import java.net.Socket;

/**
 * Created by Girish Bhalerao on 5/4/2017.
 */
public class MainActivity extends AppCompatActivity implements View.OnClickListener {

    final Handler handler = new Handler();

    private Button buttonStartReceiving;
    private Button buttonStopReceiving;
    private TextView textViewDataFromClient;
    private boolean end = false;

    @Override
    protected void onCreate(Bundle savedInstanceState) {
        super.onCreate(savedInstanceState);
        setContentView(R.layout.activity_main);

        buttonStartReceiving = (Button) findViewById(R.id.btn_start_receiving);
        buttonStopReceiving = (Button) findViewById(R.id.btn_stop_receiving);
        textViewDataFromClient = (TextView) findViewById(R.id.tv_data_from_client);

        buttonStartReceiving.setOnClickListener(this);
        buttonStopReceiving.setOnClickListener(this);

    }

    private void startServerSocket() {

        Thread thread = new Thread(new Runnable() {

            private String stringData = null;

            @Override
            public void run() {

                try {

                    ServerSocket ss = new ServerSocket(9002);

                    while (!end) {
                        //Server is waiting for client here, if needed
                        Socket s = ss.accept();
                        BufferedReader input = new BufferedReader(new InputStreamReader(s.getInputStream()));
                        PrintWriter output = new PrintWriter(s.getOutputStream());

                        stringData = input.readLine();
                        output.println("FROM SERVER - " + stringData.toUpperCase());
                        output.flush();

                        try {
                            Thread.sleep(1000);
                        } catch (InterruptedException e) {
                            e.printStackTrace();
                        }
                        updateUI(stringData);
                        if (stringData.equalsIgnoreCase("STOP")) {
                            end = true;
                            output.close();
                            s.close();
                            break;
                        }

                        output.close();
                        s.close();
                    }
                    ss.close();
                } catch (IOException e) {
                    e.printStackTrace();
                }
            }

        });
        thread.start();
    }

    private void updateUI(final String stringData) {

        handler.post(new Runnable() {
            @Override
            public void run() {

                String s = textViewDataFromClient.getText().toString();
                if (stringData.trim().length() != 0)
                    textViewDataFromClient.setText(s + "\n" + "From Client : " + stringData);
            }
        });
    }

    @Override
    public void onClick(View v) {

        switch (v.getId()) {
            case R.id.btn_start_receiving:

                startServerSocket();
                buttonStartReceiving.setEnabled(false);
                buttonStopReceiving.setEnabled(true);
                break;

            case R.id.btn_stop_receiving:

                //stopping server socket logic you can add yourself
                buttonStartReceiving.setEnabled(true);
                buttonStopReceiving.setEnabled(false);
                break;
        }
    }
}

Is a Python list guaranteed to have its elements stay in the order they are inserted in?

I suppose one thing that may be concerning you is whether or not the entries could change, so that the 2 becomes a different number, for instance. You can put your mind at ease here, because in Python, integers are immutable, meaning they cannot change after they are created.

Not everything in Python is immutable, though. For example, lists are mutable---they can change after being created. So for example, if you had a list of lists

>>> a = [[1], [2], [3]]
>>> a[0].append(7)
>>> a
[[1, 7], [2], [3]]

Here, I changed the first entry of a (I added 7 to it). One could imagine shuffling things around, and getting unexpected things here if you are not careful (and indeed, this does happen to everyone when they start programming in Python in some way or another; just search this site for "modifying a list while looping through it" to see dozens of examples).

It's also worth pointing out that x = x + [a] and x.append(a) are not the same thing. The second one mutates x, and the first one creates a new list and assigns it to x. To see the difference, try setting y = x before adding anything to x and trying each one, and look at the difference the two make to y.

Using app.config in .Net Core

I have a .Net Core 3.1 MSTest project with similar issue. This post provided clues to fix it.

Breaking this down to a simple answer for .Net core 3.1:

  • add/ensure nuget package: System.Configuration.ConfigurationManager to project
  • add your app.config(xml) to project.

If it is a MSTest project:

  • rename file in project to testhost.dll.config

    OR

  • Use post-build command provided by DeepSpace101

Use tnsnames.ora in Oracle SQL Developer

On the newer versions of macOS, one also has to set java.library.path. The easiest/safest way to do that [1] is by creating ~/.sqldeveloper/<version>/sqldeveloper.conf file and populating it as such:

AddVMOption -Djava.library.path=<instant client directory>

[1] https://community.oracle.com/message/14132189#14132189

svn cleanup: sqlite: database disk image is malformed

Do not waste your time on checking integrity or deleting data from work queue table because these are temporary solutions and it will hit you back after a while.

Just do another checkout and replace the existing .svn folder with the new one. Do an update and then it should go smooth.

Use xml.etree.ElementTree to print nicely formatted xml files

You can use the function toprettyxml() from xml.dom.minidom in order to do that:

def prettify(elem):
    """Return a pretty-printed XML string for the Element.
    """
    rough_string = ElementTree.tostring(elem, 'utf-8')
    reparsed = minidom.parseString(rough_string)
    return reparsed.toprettyxml(indent="\t")

The idea is to print your Element in a string, parse it using minidom and convert it again in XML using the toprettyxml function.

Source: http://pymotw.com/2/xml/etree/ElementTree/create.html

Create a folder inside documents folder in iOS apps

Swift 3 Solution:

private func createImagesFolder() {
        // path to documents directory
        let documentDirectoryPath = NSSearchPathForDirectoriesInDomains(.documentDirectory, .userDomainMask, true).first
        if let documentDirectoryPath = documentDirectoryPath {
            // create the custom folder path
            let imagesDirectoryPath = documentDirectoryPath.appending("/images")
            let fileManager = FileManager.default
            if !fileManager.fileExists(atPath: imagesDirectoryPath) {
                do {
                    try fileManager.createDirectory(atPath: imagesDirectoryPath,
                                                    withIntermediateDirectories: false,
                                                    attributes: nil)
                } catch {
                    print("Error creating images folder in documents dir: \(error)")
                }
            }
        }
    }