Programs & Examples On #Xinc

Xinc is a continuous integration server written in PHP 5

pip is not able to install packages correctly: Permission denied error

Set up a virtualenv:

% curl -kLso /tmp/get-pip.py https://bootstrap.pypa.io/get-pip.py 
% sudo python /tmp/get-pip.py

These commands install pip into the global site-packages directory.

% sudo pip install virtualenv

and ditto for virtualenv:

% mkdir -p ~/.virtualenvs

I like my virtualenvs under one tree in my home directory called .virtualenvs

% virtualenv ~/.virtualenvs/lxmltest

Creates a virtualenv.

% . ~/.virtualenvs/lxmltest/bin/activate

Removes the need to specify the full path to pip/python in this virtualenv.

% pip install lxml

Alternatively execute ~/.virtualenvs/lxmltest/bin/pip install lxml if you chose not to follow the previous step. Note, I'm not sure how far along you are, so some of these steps can be safely skipped. Of course, if you mess something up, you can always rm -Rf ~/.virtualenvs/lxmltest and start again from a new virtualenv.

What does elementFormDefault do in XSD?

New, detailed answer and explanation to an old, frequently asked question...

Short answer: If you don't add elementFormDefault="qualified" to xsd:schema, then the default unqualified value means that locally declared elements are in no namespace.

There's a lot of confusion regarding what elementFormDefault does, but this can be quickly clarified with a short example...

Streamlined version of your XSD:

<?xml version="1.0" encoding="UTF-8"?>
<schema xmlns="http://www.w3.org/2001/XMLSchema"
        xmlns:target="http://www.levijackson.net/web340/ns"
        targetNamespace="http://www.levijackson.net/web340/ns">
  <element name="assignments">
    <complexType>
      <sequence>
        <element name="assignment" type="target:assignmentInfo" 
                 minOccurs="1" maxOccurs="unbounded"/>
      </sequence>
    </complexType>
  </element>
  <complexType name="assignmentInfo">
    <sequence>
      <element name="name" type="string"/>
    </sequence>
    <attribute name="id" type="string" use="required"/>
  </complexType>
</schema>

Key points:

  • The assignment element is locally defined.
  • Elements locally defined in XSD are in no namespace by default.
    • This is because the default value for elementFormDefault is unqualified.
    • This arguably is a design mistake by the creators of XSD.
    • Standard practice is to always use elementFormDefault="qualified" so that assignment is in the target namespace as one would expect.
  • It is a rarely used form attribute on xs:element declarations for which elementFormDefault establishes default values.

Seemingly Valid XML

This XML looks like it should be valid according to the above XSD:

<assignments xmlns="http://www.levijackson.net/web340/ns"
             xmlns:xsi="http://www.w3.org/2001/XMLSchema-instance"
             xsi:schemaLocation="http://www.levijackson.net/web340/ns try.xsd">
  <assignment id="a1">
    <name>John</name>
  </assignment>
</assignments>

Notice:

  • The default namespace on assignments places assignments and all of its descendents in the default namespace (http://www.levijackson.net/web340/ns).

Perplexing Validation Error

Despite looking valid, the above XML yields the following confusing validation error:

[Error] try.xml:4:23: cvc-complex-type.2.4.a: Invalid content was found starting with element 'assignment'. One of '{assignment}' is expected.

Notes:

  • You would not be the first developer to curse this diagnostic that seems to say that the content is invalid because it expected to find an assignment element but it actually found an assignment element. (WTF)
  • What this really means: The { and } around assignment means that validation was expecting assignment in no namespace here. Unfortunately, when it says that it found an assignment element, it doesn't mention that it found it in a default namespace which differs from no namespace.

Solution

  • Vast majority of the time: Add elementFormDefault="qualified" to the xsd:schema element of the XSD. This means valid XML must place elements in the target namespace when locally declared in the XSD; otherwise, valid XML must place locally declared elements in no namespace.
  • Tiny minority of the time: Change the XML to comply with the XSD's requirement that assignment be in no namespace. This can be achieved, for example, by adding xmlns="" to the assignment element.

Credits: Thanks to Michael Kay for helpful feedback on this answer.

JQuery get all elements by class name

Maybe not as clean or efficient as the already posted solutions, but how about the .each() function? E.g:

var mvar = "";
$(".mbox").each(function() {
    console.log($(this).html());
    mvar += $(this).html();
});
console.log(mvar);

Javascript - check array for value

Try this:

// this will fix old browsers
if (!Array.prototype.indexOf) {
  Array.prototype.indexOf = function(value) {
    for (var i = 0; i < this.length; i++) {
      if (this[i] === value) {
        return i;
      }
    }

    return -1;
  }
}

// example
if ([1, 2, 3].indexOf(2) != -1) {
  // yay!
}

Android M Permissions: onRequestPermissionsResult() not being called

Here i want to show my code how i managed this.

public class CheckPermission {

public Context context;

public static final int PERMISSION_REQUEST_CODE =  200;

public CheckPermission(Context context){
    this.context = context;
}

public boolean isPermissionGranted(){
    int read_contact = ContextCompat.checkSelfPermission(context.getApplicationContext() , READ_CONTACTS);
    int phone = ContextCompat.checkSelfPermission(context.getApplicationContext() , CALL_PHONE);

    return read_contact == PackageManager.PERMISSION_GRANTED && phone == PackageManager.PERMISSION_GRANTED;
   }
}

Here in this class i want to check permission granted or not. Is not then i will call permission from my MainActivity like

public void requestForPermission() {
       ActivityCompat.requestPermissions(MainActivity.this, new String[]    {READ_CONTACTS, CALL_PHONE}, PERMISSION_REQUEST_CODE);
}

@Override
public void onRequestPermissionsResult(int requestCode, @NonNull String[] permissions, @NonNull int[] grantResults) {
    super.onRequestPermissionsResult(requestCode, permissions, grantResults);
    switch (requestCode) {
        case PERMISSION_REQUEST_CODE:
            if (Build.VERSION.SDK_INT >= Build.VERSION_CODES.M) {
                if (shouldShowRequestPermissionRationale(ACCESS_FINE_LOCATION)) {
                    showMessageOKCancel("You need to allow access to both the permissions",
                            new DialogInterface.OnClickListener() {
                                @Override
                                public void onClick(DialogInterface dialog, int which) {
                                    if (Build.VERSION.SDK_INT >= Build.VERSION_CODES.M) {
                                        requestPermissions(new String[]{Manifest.permission.READ_CONTACTS, Manifest.permission.CALL_PHONE},
                                                PERMISSION_REQUEST_CODE);
                                    }
                                }
                            });
                    return;
                }
            }
    }
}

Now in the onCreate method you need to call requestForPermission() function.

That's it.Also you can request multiple permission at a time.

Using CSS td width absolute, position

You can also use:

.rhead {
    width:300px;
}

but this will only with with some browsers, if I remember correctly IE8 does not allow this. Over all, It is safer to just put the width="" attribute in the <td> itself.

Round a double to 2 decimal places

I think this is easier:

double time = 200.3456;
DecimalFormat df = new DecimalFormat("#.##");      
time = Double.valueOf(df.format(time));

System.out.println(time); // 200.35

Note that this will actually do the rounding for you, not just formatting.

Postgres user does not exist?

psql -U postgres

Worked fine for me in case of db name: postgres & username: postgres. So you do not need to write sudo.

And in the case other db, you may try

psql -U yourdb postgres

As it is given in Postgres help:

psql [OPTION]... [DBNAME [USERNAME]]

In Python, how do you convert seconds since epoch to a `datetime` object?

Note that datetime.datetime.fromtimestamp(timestamp) and .utcfromtimestamp(timestamp) fail on windows for dates before Jan. 1, 1970 while negative unix timestamps seem to work on unix-based platforms. The docs say this:

"This may raise ValueError, if the timestamp is out of the range of values supported by the platform C gmtime() function. It’s common for this to be restricted to years in 1970 through 2038"

See also Issue1646728

How to calculate the IP range when the IP address and the netmask is given?

I would recommend the use of IPNetwork Library https://github.com/lduchosal/ipnetwork. As of version 2, it supports IPv4 and IPv6 as well.

IPv4

  IPNetwork ipnetwork = IPNetwork.Parse("192.168.0.1/25");

  Console.WriteLine("Network : {0}", ipnetwork.Network);
  Console.WriteLine("Netmask : {0}", ipnetwork.Netmask);
  Console.WriteLine("Broadcast : {0}", ipnetwork.Broadcast);
  Console.WriteLine("FirstUsable : {0}", ipnetwork.FirstUsable);
  Console.WriteLine("LastUsable : {0}", ipnetwork.LastUsable);
  Console.WriteLine("Usable : {0}", ipnetwork.Usable);
  Console.WriteLine("Cidr : {0}", ipnetwork.Cidr);

Output

  Network : 192.168.0.0
  Netmask : 255.255.255.128
  Broadcast : 192.168.0.127
  FirstUsable : 192.168.0.1
  LastUsable : 192.168.0.126
  Usable : 126
  Cidr : 25

Have fun !

How to get the file-path of the currently executing javascript code

I may be misunderstanding your question but it seems you should just be able to use a relative path as long as the production and development servers use the same path structure.

<script language="javascript" src="js/myLib.js" />

PostgreSQL: How to make "case-insensitive" query

Use LOWER function to convert the strings to lower case before comparing.

Try this:

SELECT id 
  FROM groups
 WHERE LOWER(name)=LOWER('Administrator')

Prevent cell numbers from incrementing in a formula in Excel

There is something called 'locked reference' in excel which you can use for this, and you use $ symbols to lock a range. For your example, you would use:

=IF(B4<>"",B4/B$1,"")

This locks the 1 in B1 so that when you copy it to rows below, 1 will remain the same.

If you use $B$1, the range will not change when you copy it down a row or across a column.

Failed to instantiate module error in Angular js

For me the solution was fixing a syntax error:

removing a unwanted semi colon in the angular.module function

RESTful Authentication via Spring

Why don't you start using OAuth with JSON WebTokens

http://projects.spring.io/spring-security-oauth/

OAuth2 is an standardized authorization protocol/framework. As per Official OAuth2 Specification:

You can find more info here

How to discard local changes and pull latest from GitHub repository

If you already committed the changes than you would have to revert changes.

If you didn't commit yet, just do a clean checkout git checkout .

Amazon S3 boto - how to create a folder?

There is no concept of folders or directories in S3. You can create file names like "abc/xys/uvw/123.jpg", which many S3 access tools like S3Fox show like a directory structure, but it's actually just a single file in a bucket.

HTML5 Audio stop function

Instead of stop() you could try with:

sound.pause();
sound.currentTime = 0;

This should have the desired effect.

How to avoid scientific notation for large numbers in JavaScript?

Your question:

number :0x68656c6c6f206f72656f
display:4.9299704811152646e+23

You can use this: https://github.com/MikeMcl/bignumber.js

A JavaScript library for arbitrary-precision decimal and non-decimal arithmetic.

like this:

let ten =new BigNumber('0x68656c6c6f206f72656f',16);
console.log(ten.toString(10));
display:492997048111526447310191

WordPress: get author info from post id

I figured it out.

<?php $author_id=$post->post_author; ?>
<img src="<?php the_author_meta( 'avatar' , $author_id ); ?> " width="140" height="140" class="avatar" alt="<?php echo the_author_meta( 'display_name' , $author_id ); ?>" />
<?php the_author_meta( 'user_nicename' , $author_id ); ?> 

WinError 2 The system cannot find the file specified (Python)

I believe you need to .f file as a parameter, not as a command-single-string. same with the "--domain "+i, which i would split in two elements of the list. Assuming that:

  • you have the path set for FORTRAN executable,
  • the ~/ is indeed the correct way for the FORTRAN executable

I would change this line:

subprocess.Popen(["FORTRAN ~/C:/Users/Vishnu/Desktop/Fortran_Program_Rum/phase1.f", "--domain "+i])

to

subprocess.Popen(["FORTRAN", "~/C:/Users/Vishnu/Desktop/Fortran_Program_Rum/phase1.f", "--domain", i])

If that doesn't work, you should do a os.path.exists() for the .f file, and check that you can launch the FORTRAN executable without any path, and set the path or system path variable accordingly

[EDIT 6-Mar-2017]

As the exception, detailed in the original post, is a python exception from subprocess; it is likely that the WinError 2 is because it cannot find FORTRAN

I highly suggest that you specify full path for your executable:

for i in input:
    exe = r'c:\somedir\fortrandir\fortran.exe'
    fortran_script = r'~/C:/Users/Vishnu/Desktop/Fortran_Program_Rum/phase1.f'
    subprocess.Popen([exe, fortran_script, "--domain", i])

if you need to convert the forward-slashes to backward-slashes, as suggested in one of the comments, you can do this:

for i in input:
    exe = os.path.normcase(r'c:\somedir\fortrandir\fortran.exe')
    fortran_script = os.path.normcase(r'~/C:/Users/Vishnu/Desktop/Fortran_Program_Rum/phase1.f')
    i = os.path.normcase(i)
    subprocess.Popen([exe, fortran_script, "--domain", i])

[EDIT 7-Mar-2017]

The following line is incorrect:

exe = os.path.normcase(r'~/C:/Program Files (x86)/Silverfrost/ftn95.exe'

I am not sure why you have ~/ as a prefix for every path, don't do that.

for i in input:
    exe = os.path.normcase(r'C:/Program Files (x86)/Silverfrost/ftn95.exe'
    fortran_script = os.path.normcase(r'C:/Users/Vishnu/Desktop/Fortran_Program_Rum/phase1.f')
    i = os.path.normcase(i)
    subprocess.Popen([exe, fortran_script, "--domain", i])

[2nd EDIT 7-Mar-2017]

I do not know this FORTRAN or ftn95.exe, does it need a shell to function properly?, in which case you need to launch as follows:

subprocess.Popen([exe, fortran_script, "--domain", i], shell = True)

You really need to try to launch the command manually from the working directory which your python script is operating from. Once you have the command which is actually working, then build up the subprocess command.

Gradients on UIView and UILabels On iPhone

I realize this is an older thread, but for future reference:

As of iPhone SDK 3.0, custom gradients can be implemented very easily, without subclassing or images, by using the new CAGradientLayer:

 UIView *view = [[[UIView alloc] initWithFrame:CGRectMake(0, 0, 320, 100)] autorelease];
 CAGradientLayer *gradient = [CAGradientLayer layer];
 gradient.frame = view.bounds;
 gradient.colors = [NSArray arrayWithObjects:(id)[[UIColor blackColor] CGColor], (id)[[UIColor whiteColor] CGColor], nil];
 [view.layer insertSublayer:gradient atIndex:0];

Take a look at the CAGradientLayer docs. You can optionally specify start and end points (in case you don't want a linear gradient that goes straight from the top to the bottom), or even specific locations that map to each of the colors.

Xcode Project vs. Xcode Workspace - Differences

I think there are three key items you need to understand regarding project structure: Targets, projects, and workspaces. Targets specify in detail how a product/binary (i.e., an application or library) is built. They include build settings, such as compiler and linker flags, and they define which files (source code and resources) actually belong to a product. When you build/run, you always select one specific target.

It is likely that you have a few targets that share code and resources. These different targets can be slightly different versions of an app (iPad/iPhone, different brandings,…) or test cases that naturally need to access the same source files as the app. All these related targets can be grouped in a project. While the project contains the files from all its targets, each target picks its own subset of relevant files. The same goes for build settings: You can define default project-wide settings in the project, but if one of your targets needs different settings, you can always override them there:

Shared project settings that all targets inherit, unless they overwrite it

Shared project settings that all targets inherit, unless they override it

Concrete target settings: PSE iPhone overwrites the project’s Base SDK setting

Concrete target settings: PSE iPhone overrides the project’s Base SDK setting

In Xcode, you always open projects (or workspaces, but not targets), and all the targets it contains can be built/run, but there’s no way/definition of building a project, so every project needs at least one target in order to be more than just a collection of files and settings.

Select one of the project’s targets to run

Select one of the project’s targets to run

In a lot of cases, projects are all you need. If you have a dependency that you build from source, you can embed it as a subproject. Subprojects can be opened separately or within their super project.

demoLib is a subprojec

demoLib is a subproject

If you add one of the subproject’s targets to the super project’s dependencies, the subproject will be automatically built unless it has remained unchanged. The advantage here is that you can edit files from both your project and your dependencies in the same Xcode window, and when you build/run, you can select from the project’s and its subprojects’ targets:

Running targets from a subproject

If, however, your library (the subproject) is used by a variety of other projects (or their targets, to be precise), it makes sense to put it on the same hierarchy level – that’s what workspaces are for. Workspaces contain and manage projects, and all the projects it includes directly (i.e., not their subprojects) are on the same level and their targets can depend on each other (projects’ targets can depend on subprojects’ targets, but not vice versa).

Workspace structure

Workspace structure

In this example, both apps (AnotherApplication / ProjectStructureExample) can reference the demoLib project’s targets. This would also be possible by including the demoLib project in both other projects as a subproject (which is a reference only, so no duplication necessary), but if you have lots of cross-dependencies, workspaces make more sense. If you open a workspace, you can choose from all projects’ targets when building/running.

Running targets from a workspace

You can still open your project files separately, but it is likely their targets won’t build because Xcode cannot resolve the dependencies unless you open the workspace file. Workspaces give you the same benefit as subprojects: Once a dependency changes, Xcode will rebuild it to make sure it’s up-to-date (although I have had some issues with that, it doesn’t seem to work reliably).

Your questions in a nutshell:

1) Projects contain files (code/resouces), settings, and targets that build products from those files and settings. Workspaces contain projects which can reference each other.

2) Both are responsible for structuring your overall project, but on different levels.

3) I think projects are sufficient in most cases. Don’t use workspaces unless there’s a specific reason. Plus, you can always embed your project in a workspace later.

4) I think that’s what the above text is for…

There’s one remark for 3): CocoaPods, which automatically handles 3rd party libraries for you, uses workspaces. Therefore, you have to use them, too, when you use CocoaPods (which a lot of people do).

Display List in a View MVC

Your action method considers model type asList<string>. But, in your view you are waiting for IEnumerable<Standings.Models.Teams>. You can solve this problem with changing the model in your view to List<string>.

But, the best approach would be to return IEnumerable<Standings.Models.Teams> as a model from your action method. Then you haven't to change model type in your view.

But, in my opinion your models are not correctly implemented. I suggest you to change it as:

public class Team
{
    public int Position { get; set; }
    public string HomeGround {get; set;}
    public string NickName {get; set;}
    public int Founded { get; set; }
    public string Name { get; set; }
}

Then you must change your action method as:

public ActionResult Index()
{
    var model = new List<Team>();

    model.Add(new Team { Name = "MU"});
    model.Add(new Team { Name = "Chelsea"});
    ...

    return View(model);
}

And, your view:

@model IEnumerable<Standings.Models.Team>

@{
     ViewBag.Title = "Standings";
}

@foreach (var item in Model)
{
    <div>
        @item.Name
        <hr />
    </div>
}

How do I separate an integer into separate digits in an array in JavaScript?

_x000D_
_x000D_
const toIntArray = (n) => ([...n + ""].map(v => +v))
_x000D_
_x000D_
_x000D_

Downloading a picture via urllib and python

Using requests

import requests
import shutil,os

headers = {
    'user-agent': 'Mozilla/5.0 (Windows NT 10.0; Win64; x64) AppleWebKit/537.36 (KHTML, like Gecko) Chrome/78.0.3904.108 Safari/537.36'
}
currentDir = os.getcwd()
path = os.path.join(currentDir,'Images')#saving images to Images folder

def ImageDl(url):
    attempts = 0
    while attempts < 5:#retry 5 times
        try:
            filename = url.split('/')[-1]
            r = requests.get(url,headers=headers,stream=True,timeout=5)
            if r.status_code == 200:
                with open(os.path.join(path,filename),'wb') as f:
                    r.raw.decode_content = True
                    shutil.copyfileobj(r.raw,f)
            print(filename)
            break
        except Exception as e:
            attempts+=1
            print(e)

if __name__ == '__main__':
    ImageDl(url)

Solve error javax.mail.AuthenticationFailedException

Just in case anyone comes looking a solution for this problem.

The Authentication problems can be alleviated by activating the google 2-step verification for the account in use and creating an app specific password. I had the same problem as the OP. Enabling 2-step worked.

How to change line-ending settings

If you want to convert back the file formats which have been changed to UNIX Format from PC format.

(1)You need to reinstall tortoise GIT and in the "Line Ending Conversion" Section make sure that you have selected "Check out as is - Check in as is"option.

(2)and keep the remaining configurations as it is.

(3)once installation is done

(4)write all the file extensions which are converted to UNIX format into a text file (extensions.txt).

ex:*.dsp
   *.dsw

(5) copy the file into your clone Run the following command in GITBASH

while read -r a;
do
find . -type f -name "$a" -exec dos2unix {} \;
done<extension.txt

How to check if a number is between two values?

Tests whether windowsize is greater than 500 and lesser than 600 meaning that neither values 500 or 600 itself will result in the condition becoming true.

if (windowsize > 500 && windowsize < 600) {
  // ...
}

How do I specify unique constraint for multiple columns in MySQL?

This works for mysql version 5.5.32

ALTER TABLE  `tablename` ADD UNIQUE (`column1` ,`column2`);

get UTC timestamp in python with datetime

If input datetime object is in UTC:

>>> dt = datetime(2008, 1, 1, 0, 0, 0, 0)
>>> timestamp = (dt - datetime(1970, 1, 1)).total_seconds()
1199145600.0

Note: it returns float i.e., microseconds are represented as fractions of a second.

If input date object is in UTC:

>>> from datetime import date
>>> utc_date = date(2008, 1, 1)
>>> timestamp = (utc_date.toordinal() - date(1970, 1, 1).toordinal()) * 24*60*60
1199145600

See more details at Converting datetime.date to UTC timestamp in Python.

SQL TRUNCATE DATABASE ? How to TRUNCATE ALL TABLES

As my purpose is to get an empty version of the test database to import data from an external previous current active source (Access database) once all is fine tuned. I found that using DBCC CloneDatabase with Verify_CloneDB option fits perfectly.

How to check if a Ruby object is a Boolean

So try this out (x == true) ^ (x == false) note you need the parenthesis but this is more beautiful and compact.

It even passes the suggested like "cuak" but not a "cuak"... class X; def !; self end end ; x = X.new; (x == true) ^ (x == false)

Note: See that this is so basic that you can use it in other languages too, that doesn't provide a "thing is boolean".

Note 2: Also you can use this to say thing is one of??: "red", "green", "blue" if you add more XORS... or say this thing is one of??: 4, 5, 8, 35.

SQLite3 database or disk is full / the database disk image is malformed

I have seen this happen when the database gets corrupted, have you tried cloning it into a new one ?

Safley copy a s SQLite db

Safely copy a SQLite database

It's trivially easy to copy a SQLite database. It's less trivial to do this in a way that won't corrupt it. Here's how:

shell$ sqlite3 some.db
sqlite> begin immediate;
<press CTRL+Z>
shell$ cp some.db some.db.backup
shell$ exit
sqlite> rollback;

This will give you a nice clean backup that's sure to be in a proper state, since writing to the database half-way through your copying process is impossible.

What arguments are passed into AsyncTask<arg1, arg2, arg3>?

  • in Short, There are 3 parameters in AsyncTask

    1. parameters for Input use in DoInBackground(String... params)

    2. parameters for show status of progress use in OnProgressUpdate(String... status)

    3. parameters for result use in OnPostExcute(String... result)

    Note : - [Type of parameters can vary depending on your requirement]

Sum function in VBA

Range("A1").Function="=SUM(Range(Cells(2,1),Cells(3,2)))"

won't work because worksheet functions (when actually used on a worksheet) don't understand Range or Cell

Try

Range("A1").Formula="=SUM(" & Range(Cells(2,1),Cells(3,2)).Address(False,False) & ")"

Simple dynamic breadcrumb

This may be overkill for a simple breadcrumb, but it's worth a shot. I remember having this issue a long time ago when I first started, but I never really solved it. That is, until I just decided to write this up now. :)

I have documented as best I can inline, at the bottom are 3 possible use cases. Enjoy! (feel free to ask any questions you may have)

<?php

// This function will take $_SERVER['REQUEST_URI'] and build a breadcrumb based on the user's current path
function breadcrumbs($separator = ' &raquo; ', $home = 'Home') {
    // This gets the REQUEST_URI (/path/to/file.php), splits the string (using '/') into an array, and then filters out any empty values
    $path = array_filter(explode('/', parse_url($_SERVER['REQUEST_URI'], PHP_URL_PATH)));

    // This will build our "base URL" ... Also accounts for HTTPS :)
    $base = ($_SERVER['HTTPS'] ? 'https' : 'http') . '://' . $_SERVER['HTTP_HOST'] . '/';

    // Initialize a temporary array with our breadcrumbs. (starting with our home page, which I'm assuming will be the base URL)
    $breadcrumbs = Array("<a href=\"$base\">$home</a>");

    // Find out the index for the last value in our path array
    $last = end(array_keys($path));

    // Build the rest of the breadcrumbs
    foreach ($path AS $x => $crumb) {
        // Our "title" is the text that will be displayed (strip out .php and turn '_' into a space)
        $title = ucwords(str_replace(Array('.php', '_'), Array('', ' '), $crumb));

        // If we are not on the last index, then display an <a> tag
        if ($x != $last)
            $breadcrumbs[] = "<a href=\"$base$crumb\">$title</a>";
        // Otherwise, just display the title (minus)
        else
            $breadcrumbs[] = $title;
    }

    // Build our temporary array (pieces of bread) into one big string :)
    return implode($separator, $breadcrumbs);
}

?>

<p><?= breadcrumbs() ?></p>
<p><?= breadcrumbs(' > ') ?></p>
<p><?= breadcrumbs(' ^^ ', 'Index') ?></p>

OpenCV - DLL missing, but it's not?

This might be like resurrecting a dead horse. But just so it's out there, the reason why the answer to these types of questions to simply put dll's into the system32 folder is because that folder is in the os's system path.

It's actually best practice to provide the os with a path link.

With windows 10

  1. open up file explorer
  2. right click on "this pc" and select "properties"
  3. Now in the "Control Panel\System and Security\System" window that comes up, click on "Advanced System Settings" from the left hand panel.
  4. At the bottom of the next window, click on the "Environment Variables" button.
  5. On the next window, there are two panels, the top one is for modifying variables to the current user, and the bottom panel is for modifying variables to the system. On the bottom panel, find the variable "Path" and click it to select it, then click on the "edit" button.
  6. Here you can then create, edit, delete, or update the different paths for the system. For example, to add mingw32-make to the system so you can access that command via command prompt, click new, then paste in the path to the bin. Example path, "D:\Qt\Tools\mingw730_64\bin", no quotation marks nor additional whitespaces.
  7. Click ok on all the windows so that the changes are saved, then reboot your computer for the changes to be loaded.

FirstOrDefault: Default value other than null

I just had a similar situation and was looking for a solution that allows me to return an alternative default value without taking care of it at the caller side every time I need it. What we usually do in case Linq does not support what we want, is to write a new extension that takes care of it. That´s what I did. Here is what I came up with (not tested though):

public static class EnumerableExtensions
{
    public static T FirstOrDefault<T>(this IEnumerable<T> items, T defaultValue)
    {
        foreach (var item in items)
        {
            return item;
        }
        return defaultValue;
    }

    public static T FirstOrDefault<T>(this IEnumerable<T> items, Func<T, bool> predicate, T defaultValue)
    {
        return items.Where(predicate).FirstOrDefault(defaultValue);
    }

    public static T LastOrDefault<T>(this IEnumerable<T> items, T defaultValue)
    {
        return items.Reverse().FirstOrDefault(defaultValue);
    }

    public static T LastOrDefault<T>(this IEnumerable<T> items, Func<T, bool> predicate, T defaultValue)
    {
        return items.Where(predicate).LastOrDefault(defaultValue);
    }
}

How to find and return a duplicate value in array

Simply find the first instance where the index of the object (counting from the left) does not equal the index of the object (counting from the right).

arr.detect {|e| arr.rindex(e) != arr.index(e) }

If there are no duplicates, the return value will be nil.

I believe this is the fastest solution posted in the thread so far, as well, since it doesn't rely on the creation of additional objects, and #index and #rindex are implemented in C. The big-O runtime is N^2 and thus slower than Sergio's, but the wall time could be much faster due to the the fact that the "slow" parts run in C.

Color a table row with style="color:#fff" for displaying in an email

For email templates, inline CSS is the properly used method to style:

<thead>
    <tr style="color: #fff; background: black;">
        <th>Header 1</th>
        <th>Header 2</th>
        <th>Header 3</th>
    </tr>
</thead>

How to drop columns by name in a data frame

df2 <- df[!names(df) %in% c("c1", "c2")]

ASP.NET DateTime Picker

If you would like to work with a textbox, be aware that setting the TextMode property to "Date" will not work on Internet Explorer 11, because it does not currently support the "Date", "DateTime", nor "Time" values.

This example illustrates how to implement it using a textbox, including validation of the dates (since the user could enter just numbers). It will work on Internet Explorer 11 as well other web browsers.

<asp:Content ID="Content"
         ContentPlaceHolderID="MainContent"
         runat="server">

<link rel="stylesheet"
    href="//code.jquery.com/ui/1.12.1/themes/base/jquery-ui.css" />
   <script src="https://code.jquery.com/ui/1.12.1/jquery-ui.js"></script>
   <script>
   $(function () {
   $("#
   <%= txtBoxDate.ClientID %>").datepicker();
   });
 </script>
 <asp:TextBox ID="txtBoxDate"
           runat="server"
           Width="135px"
           AutoPostBack="False"
           TabIndex="1"
           placeholder="mm/dd/yyyy"
           autocomplete="off"
           MaxLength="10"></asp:TextBox>
 <asp:CompareValidator ID="CompareValidator1"
                    runat="server"
                    ControlToValidate="txtBoxDate"
                    Operator="DataTypeCheck"
                    Type="Date">Date invalid, please check format. 
 </asp:CompareValidator>
 </asp:Content>

How can one tell the version of React running at runtime in the browser?

It is not certain that any global ECMAScript variables have been exported and html/css does not necessarily indicate React. So look in the .js.

Method 1: Look in ECMAScript:

The version number is exported by both modules react-dom and react but those names are often removed by bundling and the version hidden inside an execution context that cannot be accessed. A clever break point may reveal the value directly, or you can search the ECMAScript:

  1. Load the Web page (you can try https://www.instagram.com they’re total Coolaiders)
  2. Open Chrome Developer Tools on Sources tab (control+shift+i or command+shift+i)
    1. Dev tools open on the Sources tab
  3. In the very right of the top menu bar, click the vertical ellipsis and select search all files
  4. In he search box down on left type FIRED in capital letters, clear the checkbox Ignore case, type Enter
    1. One or more matches appear below. The version is an export very close to the search string looking like version: "16.0.0"
  5. If the version number is not immediately visible: double click a line that begins with a line number
    1. ECMAScript appears in the middle pane
  6. If the version number is not immediately visible: click the two braces at bottom left of the ECMAScript pane {}
    1. ECMAScript is reformatted and easier to read
  7. If the version number is not immediately visible: scroll up and down a few lines to find it or try another search key
    1. If the code is not minified, search for ReactVersion There should be 2 hits with the same value
    2. If the code is minified, search for either SECRET_INTERNALS_DO_NOT_USE_OR_YOU_WILL_BE_FIRED or react-dom
    3. Or search for the likely version string itself: "15. or "16. or even "0.15

Method 2: Use a DOM breakpoint:

  1. Load the page rendered by React
  2. Right click a React element (anything, like an input field or a box) and select Inspect Element
    1. Chrome Developer Tools displays the Elements pane
  3. As high up in the tree as possible from the selected element, but no higher than the React root element (often a div directly inside body with id root: <div id="root">), right click an element and select Break On… - subtree modifications
    1. Note: It is possible to compare contents of the Elements tab (DOM current state) with the response for the same resouce on the Networks tab. This may reveal React’s root element
  4. Reload the page by clicking Reload left of the address bar
    1. Chrome Developer Tools stops at the breakpoint and displays the Sources pane
  5. In the rightmost pane, examine the Call Stack sub-pane
  6. As far down the call stack as possible, there should be a render entry, this is ReactDOM.render
  7. Click the line below render, ie. the code that invokes render
  8. The middle pane now displays ECMAScript with an expression containing .render highlighted
  9. Hover the mouse cursor over the object used to invoke render, is. the react-dom module exports object
    1. if the code line goes: Object(u.render)(…, hover over the u
  10. A tooltip window is displayed containing version: "15.6.2", ie. all values exported by react-dom

The version is also injected into React dev tools, but as far as I know not displayed anywhere.

submit the form using ajax

What about

$.ajax({
  type: 'POST',
  url: $("form").attr("action"),
  data: $("form").serialize(), 
  //or your custom data either as object {foo: "bar", ...} or foo=bar&...
  success: function(response) { ... },
});

SELECT data from another schema in oracle

Depending on the schema/account you are using to connect to the database, I would suspect you are missing a grant to the account you are using to connect to the database.

Connect as PCT account in the database, then grant the account you are using select access for the table.

grant select on pi_int to Account_used_to_connect

Is it possible to compile a program written in Python?

Avoiding redundancy I don't repeat my answer here again.

Please refer to my answer here. (note that answer only covers compiling to python bytecode.)

How to ensure a <select> form field is submitted when it is disabled?

Disable the fields and then enable them before the form is submitted:

jQuery code:

jQuery(function ($) {        
  $('form').bind('submit', function () {
    $(this).find(':input').prop('disabled', false);
  });
});

Convert Xml to DataTable

I would first create a DataTable with the columns that you require, then populate it via Linq-to-XML.

You could use a Select query to create an object that represents each row, then use the standard approach for creating DataRows for each item ...

class Quest
{
    public string Answer1;
    public string Answer2;
    public string Answer3;
    public string Answer4;
}

public static void Main()
{
    var doc = XDocument.Load("filename.xml");

    var rows = doc.Descendants("QuestId").Select(el => new Quest
    {
        Answer1 = el.Element("Answer1").Value,
        Answer2 = el.Element("Answer2").Value,
        Answer3 = el.Element("Answer3").Value,
        Answer4 = el.Element("Answer4").Value,
    });

    // iterate over the rows and add to DataTable ...

}

Run C++ in command prompt - Windows

Steps to perform the task:

  1. First, download and install the compiler.

  2. Then, type the C/C++ program and save it.

  3. Then, open the command line and change directory to the particular one where the source file is stored, using cd like so:

    cd C:\Documents and Settings\...
    
  4. Then, to compile, type in the command prompt:

    gcc sourcefile_name.c -o outputfile.exe
    
  5. Finally, to run the code, type:

    outputfile.exe
    

org.hibernate.NonUniqueResultException: query did not return a unique result: 2?

Thought this might help to someone, it happens because "When the number of data queries is greater than 1".reference

How to rotate x-axis tick labels in Pandas barplot

The question is clear but the title is not as precise as it could be. My answer is for those who came looking to change the axis label, as opposed to the tick labels, which is what the accepted answer is about. (The title has now been corrected).

for ax in plt.gcf().axes:
    plt.sca(ax)
    plt.xlabel(ax.get_xlabel(), rotation=90)

indexOf and lastIndexOf in PHP?

This is the best way to do it, very simple.

$msg = "Hello this is a string";
$first_index_of_i = stripos($msg,'i');
$last_index_of_i = strripos($msg, 'i');

echo "First i : " . $first_index_of_i . PHP_EOL ."Last i : " . $last_index_of_i;

Cannot instantiate the type List<Product>

Interfaces can not be directly instantiated, you should instantiate classes that implements such Interfaces.

Try this:

NameValuePair[] params = new BasicNameValuePair[] {
        new BasicNameValuePair("param1", param1),
        new BasicNameValuePair("param2", param2),
};

How do you convert a time.struct_time object into a datetime object?

Like this:

>>> structTime = time.localtime()
>>> datetime.datetime(*structTime[:6])
datetime.datetime(2009, 11, 8, 20, 32, 35)

Remove a file from the list that will be committed

Answer:

git reset HEAD path/to/file

Docker: adding a file from a parent directory

Since -f caused another problem, I developed another solution.

  • Create a base image in the parent folder
  • Added the required files.
  • Used this image as a base image for the project which in a descendant folder.

The -f flag does not solved my problem because my onbuild image looks for a file in a folder and had to call like this:

-f foo/bar/Dockerfile foo/bar

instead of

-f foo/bar/Dockerfile .

Also note that this is only solution for some cases as -f flag

Pass multiple parameters in Html.BeginForm MVC

Another option I like, which can be generalized once I start seeing the code not conform to DRY, is to use one controller that redirects to another controller.

public ActionResult ClientIdSearch(int cid)
{
  var action = String.Format("Details/{0}", cid);

  return RedirectToAction(action, "Accounts");
}

I find this allows me to apply my logic in one location and re-use it without have to sprinkle JavaScript in the views to handle this. And, as I mentioned I can then refactor for re-use as I see this getting abused.

Flexbox: 4 items per row

Add a width to the .child elements. I personally would use percentages on the margin-left if you want to have it always 4 per row.

DEMO

.child {
    display: inline-block;
    background: blue;
    margin: 10px 0 0 2%;
    flex-grow: 1;
    height: 100px;
    width: calc(100% * (1/4) - 10px - 1px);
}

How to drop rows of Pandas DataFrame whose value in a certain column is NaN

You can use this:

df.dropna(subset=['EPS'], how='all', inplace=True)

What is the default stack size, can it grow, how does it work with garbage collection?

How much a stack can grow?

You can use a VM option named ss to adjust the maximum stack size. A VM option is usually passed using -X{option}. So you can use java -Xss1M to set the maximum of stack size to 1M.

Each thread has at least one stack. Some Java Virtual Machines(JVM) put Java stack(Java method calls) and native stack(Native method calls in VM) into one stack, and perform stack unwinding using a Managed to Native Frame, known as M2NFrame. Some JVMs keep two stacks separately. The Xss set the size of the Java Stack in most cases.

For many JVMs, they put different default values for stack size on different platforms.

Can we limit this growth?

When a method call occurs, a new stack frame will be created on the stack of that thread. The stack will contain local variables, parameters, return address, etc. In java, you can never put an object on stack, only object reference can be stored on stack. Since array is also an object in java, arrays are also not stored on stack. So, if you reduce the amount of your local primitive variables, parameters by grouping them into objects, you can reduce the space on stack. Actually, the fact that we cannot explicitly put objects on java stack affects the performance some time(cache miss).

Does stack has some default minimum value or default maximum value?

As I said before, different VMs are different, and may change over versions. See here.

how does garbage collection work on stack?

Garbage collections in Java is a hot topic. Garbage collection aims to collect unreachable objects in the heap. So that needs a definition of 'reachable.' Everything on the stack constitutes part of the root set references in GC. Everything that is reachable from every stack of every thread should be considered as live. There are some other root set references, like Thread objects and some class objects.

This is only a very vague use of stack on GC. Currently most JVMs are using a generational GC. This article gives brief introduction about Java GC. And recently I read a very good article talking about the GC on .net. The GC on oracle jvm is quite similar so I think that might also help you.

How do I make a checkbox required on an ASP.NET form?

I typically perform the validation on the client side:

<asp:checkbox id="chkTerms" text=" I agree to the terms" ValidationGroup="vg" runat="Server"  />
<asp:CustomValidator id="vTerms"
                ClientValidationFunction="validateTerms" 
                ErrorMessage="<br/>Terms and Conditions are required." 
                ForeColor="Red"
                Display="Static"
                EnableClientScript="true"
                ValidationGroup="vg"
                runat="server"/>

<asp:Button ID="btnSubmit" OnClick="btnSubmit_Click" CausesValidation="true" Text="Submit" ValidationGroup="vg" runat="server" />

<script>
    function validateTerms(source, arguments) {
        var $c = $('#<%= chkTerms.ClientID %>');
        if($c.prop("checked")){
            arguments.IsValid = true;
        } else {
            arguments.IsValid = false;
        }
    }
</script>       

Find text string using jQuery?

Normally jQuery selectors do not search within the "text nodes" in the DOM. However if you use the .contents() function, text nodes will be included, then you can use the nodeType property to filter only the text nodes, and the nodeValue property to search the text string.

    $('*', 'body')
        .andSelf()
        .contents()
        .filter(function(){
            return this.nodeType === 3;
        })
        .filter(function(){
            // Only match when contains 'simple string' anywhere in the text
            return this.nodeValue.indexOf('simple string') != -1;
        })
        .each(function(){
            // Do something with this.nodeValue
        });

Get element of JS object with an index

I know it's a late answer, but I think this is what OP asked for.

myobj[Object.keys(myobj)[0]];

How to calculate number of days between two given dates?

from datetime import date
def d(s):
  [month, day, year] = map(int, s.split('/'))
  return date(year, month, day)
def days(start, end):
  return (d(end) - d(start)).days
print days('8/18/2008', '9/26/2008')

This assumes, of course, that you've already verified that your dates are in the format r'\d+/\d+/\d+'.

How to load property file from classpath?

If you use the static method and load the properties file from the classpath folder so you can use the below code :

//load a properties file from class path, inside static method
Properties prop = new Properties();
prop.load(Classname.class.getClassLoader().getResourceAsStream("foo.properties"));

hide div tag on mobile view only?

You will need two things. The first is @media screen to activate the specific code at a certain screen size, used for responsive design. The second is the use of the visibility: hidden attribute. Once the browser/screen reaches 600pixels then #title_message will become hidden.

@media screen and (max-width: 600px) {
  #title_message {
    visibility: hidden;
    clear: both;
    float: left;
    margin: 10px auto 5px 20px;
    width: 28%;
    display: none;
  }
}

EDIT: if you are using another CSS for mobile then just add the visibility: hidden; to #title_message. Hope this helps you!

C# Base64 String to JPEG Image

So with the code you have provided.

var bytes = Convert.FromBase64String(resizeImage.Content);
using (var imageFile = new FileStream(filePath, FileMode.Create))
{
    imageFile.Write(bytes ,0, bytes.Length);
    imageFile.Flush();
}

How to use goto statement correctly

Java also does not use line numbers, which is a necessity for a GOTO function. Unlike C/C++, Java does not have goto statement, but java supports label. The only place where a label is useful in Java is right before nested loop statements. We can specify label name with break to break out a specific outer loop.

String format currency

You need to provide an IFormatProvider:

@String.Format(new CultureInfo("en-US"), "{0:C}", @price)

How do I change Eclipse to use spaces instead of tabs?

Eclipse IDE for C/C++ Developers, Version: Helios Service Release 2

You need to create new profile by pressing New button inside "Window->Preferences->Code Style"

Go to Indentation tab and select "Tab policy = Space only"


Eclipse IDE for C/C++ Developers, Version: Kepler Service Release 1

Follow the path below to create new profile: "Window > Preferences > C/C++ > Code Style > Formatter"

Go to Indentation tab and select "Tab policy = Space only"

How unique is UUID?

If by "given enough time" you mean 100 years and you're creating them at a rate of a billion a second, then yes, you have a 50% chance of having a collision after 100 years.

apache server reached MaxClients setting, consider raising the MaxClients setting

I recommend to use bellow formula suggested on Apache:

MaxClients = (total RAM - RAM for OS - RAM for external programs) / (RAM per httpd process)

Find my script here which is running on Rhel 6.7. you can made change according to your OS.

#!/bin/bash

echo "HostName=`hostname`"

#Formula
#MaxClients . (RAM - size_all_other_processes)/(size_apache_process)
total_httpd_processes_size=`ps -ylC httpd --sort:rss | awk '{ sum += $9 } END { print sum }'`
#echo "total_httpd_processes_size=$total_httpd_processes_size"
total_http_processes_count=`ps -ylC httpd --sort:rss | wc -l`
echo "total_http_processes_count=$total_http_processes_count"
AVG_httpd_process_size=$(expr $total_httpd_processes_size / $total_http_processes_count)
echo "AVG_httpd_process_size=$AVG_httpd_process_size"
total_httpd_process_size_MB=$(expr $AVG_httpd_process_size / 1024)
echo "total_httpd_process_size_MB=$total_httpd_process_size_MB"
total_pttpd_used_size=$(expr $total_httpd_processes_size / 1024)
echo "total_pttpd_used_size=$total_pttpd_used_size"
total_RAM_size=`free -m |grep Mem |awk '{print $2}'`
echo "total_RAM_size=$total_RAM_size"
total_used_size=`free -m |grep Mem |awk '{print $3}'`
echo "total_used_size=$total_used_size"
size_all_other_processes=$(expr $total_used_size - $total_pttpd_used_size)
echo "size_all_other_processes=$size_all_other_processes"
remaining_memory=$(($total_RAM_size - $size_all_other_processes))
echo "remaining_memory=$remaining_memory"
MaxClients=$((($total_RAM_size - $size_all_other_processes) / $total_httpd_process_size_MB))
echo "MaxClients=$MaxClients"
exit

Difference between git pull and git pull --rebase

git pull = git fetch + git merge against tracking upstream branch

git pull --rebase = git fetch + git rebase against tracking upstream branch

If you want to know how git merge and git rebase differ, read this.

Can enums be subclassed to add new elements?

No, you can't do this in Java. Aside from anything else, d would then presumably be an instance of A (given the normal idea of "extends"), but users who only knew about A wouldn't know about it - which defeats the point of an enum being a well-known set of values.

If you could tell us more about how you want to use this, we could potentially suggest alternative solutions.

How to remove a Gitlab project?

  1. Open project
  2. Setting (In the left sidebar)
  3. General
  4. Advanced Setting (Click on Expand)
  5. Remove Project (Bottom of the Page)
  6. Confirm (By typing project name and press Confirm button)

How to get last N records with activerecord?

new way to do it in rails 3.1 is SomeModel.limit(5).order('id desc')

How to get the date from the DatePicker widget in Android?

If you are using Kotlin, you can define an extension function for DatePicker:

fun DatePicker.getDate(): Date {
    val calendar = Calendar.getInstance()
    calendar.set(year, month, dayOfMonth)
    return calendar.time
}

Then, it's just: datePicker.getDate(). As if it had always existed.

Concatenate a vector of strings/character

You can use stri_paste function with collapse parameter from stringi package like this:

stri_paste(letters, collapse='')
## [1] "abcdefghijklmnopqrstuvwxyz" 

And some benchmarks:

require(microbenchmark)
test <- stri_rand_lipsum(100)
microbenchmark(stri_paste(test, collapse=''), paste(test,collapse=''), do.call(paste, c(as.list(test), sep="")))
Unit: microseconds
                                      expr     min       lq     mean   median       uq     max neval
           stri_paste(test, collapse = "") 137.477 139.6040 155.8157 148.5810 163.5375 226.171   100
                paste(test, collapse = "") 404.139 406.4100 446.0270 432.3250 442.9825 723.793   100
do.call(paste, c(as.list(test), sep = "")) 216.937 226.0265 251.6779 237.3945 264.8935 405.989   100

UIView touch event in controller

Updating @Crashalot's answer for Swift 3.x:

override func touchesBegan(_ touches: Set<UITouch>, with event: UIEvent?) {
    if let touch = touches.first {
        let currentPoint = touch.location(in: self)
        // do something with your currentPoint
    }
}

override func touchesMoved(_ touches: Set<UITouch>, with event: UIEvent?) {
    if let touch = touches.first {
        let currentPoint = touch.location(in: self)
        // do something with your currentPoint
    }
}

override func touchesEnded(_ touches: Set<UITouch>, with event: UIEvent?) {
    if let touch = touches.first {
        let currentPoint = touch.location(in: self)
        // do something with your currentPoint
    }
}

AngularJS : How do I switch views from a controller function?

I've got an example working.

Here's how my doc looks:

<html>
<head>
    <link rel="stylesheet" href="css/main.css">
    <script src="//ajax.googleapis.com/ajax/libs/jquery/1.8.3/jquery.min.js"></script>
    <script src="http://ajax.googleapis.com/ajax/libs/angularjs/1.0.3/angular.min.js"></script>
    <script src="http://ajax.googleapis.com/ajax/libs/angularjs/1.0.3/angular-resource.min.js"></script>
    <script src="js/app.js"></script>
    <script src="controllers/ctrls.js"></script>
</head>
<body ng-app="app">
    <div id="contnr">
        <ng-view></ng-view>
    </div>
</body>
</html>

Here's what my partial looks like:

<div id="welcome" ng-controller="Index">
    <b>Welcome! Please Login!</b>
    <form ng-submit="auth()">
        <input class="input login username" type="text" placeholder="username" /><br>
        <input class="input login password" type="password" placeholder="password" /><br>
        <input class="input login submit" type="submit" placeholder="login!" />
    </form>
</div>

Here's what my Ctrl looks like:

app.controller('Index', function($scope, $routeParams, $location){
    $scope.auth = function(){
        $location.url('/map');
    };
});

app is my module:

var app = angular.module('app', ['ngResource']).config(function($routeProvider)...

Hope this is helpful!

class << self idiom in Ruby

First, the class << foo syntax opens up foo's singleton class (eigenclass). This allows you to specialise the behaviour of methods called on that specific object.

a = 'foo'
class << a
  def inspect
    '"bar"'
  end
end
a.inspect   # => "bar"

a = 'foo'   # new object, new singleton class
a.inspect   # => "foo"

Now, to answer the question: class << self opens up self's singleton class, so that methods can be redefined for the current self object (which inside a class or module body is the class or module itself). Usually, this is used to define class/module ("static") methods:

class String
  class << self
    def value_of obj
      obj.to_s
    end
  end
end

String.value_of 42   # => "42"

This can also be written as a shorthand:

class String
  def self.value_of obj
    obj.to_s
  end
end

Or even shorter:

def String.value_of obj
  obj.to_s
end

When inside a function definition, self refers to the object the function is being called with. In this case, class << self opens the singleton class for that object; one use of that is to implement a poor man's state machine:

class StateMachineExample
  def process obj
    process_hook obj
  end

private
  def process_state_1 obj
    # ...
    class << self
      alias process_hook process_state_2
    end
  end

  def process_state_2 obj
    # ...
    class << self
      alias process_hook process_state_1
    end
  end

  # Set up initial state
  alias process_hook process_state_1
end

So, in the example above, each instance of StateMachineExample has process_hook aliased to process_state_1, but note how in the latter, it can redefine process_hook (for self only, not affecting other StateMachineExample instances) to process_state_2. So, each time a caller calls the process method (which calls the redefinable process_hook), the behaviour changes depending on what state it's in.

Extract the last substring from a cell

Right(A1, Len(A1)-Find("(asterisk)",Substitute(A1, "(space)","(asterisk)",Len(A1)-Len(Substitute(A1,"(space)", "(no space)")))))

Try this. Hope it works.

Get exit code of a background process

1: In bash, $! holds the PID of the last background process that was executed. That will tell you what process to monitor, anyway.

4: wait <n> waits until the process with PID <n> is complete (it will block until the process completes, so you might not want to call this until you are sure the process is done), and then returns the exit code of the completed process.

2, 3: ps or ps | grep " $! " can tell you whether the process is still running. It is up to you how to understand the output and decide how close it is to finishing. (ps | grep isn't idiot-proof. If you have time you can come up with a more robust way to tell whether the process is still running).

Here's a skeleton script:

# simulate a long process that will have an identifiable exit code
(sleep 15 ; /bin/false) &
my_pid=$!

while   ps | grep " $my_pid "     # might also need  | grep -v grep  here
do
    echo $my_pid is still in the ps output. Must still be running.
    sleep 3
done

echo Oh, it looks like the process is done.
wait $my_pid
# The variable $? always holds the exit code of the last command to finish.
# Here it holds the exit code of $my_pid, since wait exits with that code. 
my_status=$?
echo The exit status of the process was $my_status

INSERT with SELECT

The right Syntax for your query is:

INSERT INTO courses (name, location, gid) 
SELECT (name, location, gid) 
FROM courses 
WHERE cid = $cid

How to get Activity's content view?

You may want to try View.getRootView().

How can I connect to Android with ADB over TCP?

I ended up getting the Eltima USB to Ethernet software working after finally giving up on the possibility of a direct to device connection over TCP. I have pretty much decided that it is not possible to connect to a device across the network only an emulator.

How to convert time milliseconds to hours, min, sec format in JavaScript?

Based on @Chand answer. This is the implementation in Typescript. A bit safer than coercing types in JS. If you remove the type annotation should be valid JS. Also using new string functions to normalise the time.

function displayTime(millisec: number) {
 const normalizeTime = (time: string): string => (time.length === 1) ? time.padStart(2, '0') : time;

 let seconds: string = (millisec / 1000).toFixed(0);
 let minutes: string = Math.floor(parseInt(seconds) / 60).toString();
 let hours: string = '';

 if (parseInt(minutes) > 59) {
   hours = normalizeTime(Math.floor(parseInt(minutes) / 60).toString());
   minutes = normalizeTime((parseInt(minutes) - (parseInt(hours) * 60)).toString());
 }
 seconds = normalizeTime(Math.floor(parseInt(seconds) % 60).toString());

 if (hours !== '') {
    return `${hours}:${minutes}:${seconds}`;
 }
   return `${minutes}:${seconds}`;
}

Optional Parameters in Go?

I am a little late, but if you like fluent interface you might design your setters for chained calls like this:

type myType struct {
  s string
  a, b int
}

func New(s string, err *error) *myType {
  if s == "" {
    *err = errors.New(
      "Mandatory argument `s` must not be empty!")
  }
  return &myType{s: s}
}

func (this *myType) setA (a int, err *error) *myType {
  if *err == nil {
    if a == 42 {
      *err = errors.New("42 is not the answer!")
    } else {
      this.a = a
    }
  }
  return this
}

func (this *myType) setB (b int, _ *error) *myType {
  this.b = b
  return this
}

And then call it like this:

func main() {
  var err error = nil
  instance :=
    New("hello", &err).
    setA(1, &err).
    setB(2, &err)

  if err != nil {
    fmt.Println("Failed: ", err)
  } else {
    fmt.Println(instance)
  }
}

This is similar to the Functional options idiom presented on @Ripounet answer and enjoys the same benefits but has some drawbacks:

  1. If an error occurs it will not abort immediately, thus, it would be slightly less efficient if you expect your constructor to report errors often.
  2. You'll have to spend a line declaring an err variable and zeroing it.

There is, however, a possible small advantage, this type of function calls should be easier for the compiler to inline but I am really not a specialist.

Parsing a pcap file in python

You might want to start with scapy.

Display / print all rows of a tibble (tbl_df)

I prefer to turn the tibble to data.frame. It shows everything and you're done

df %>% data.frame 

How can I clear the SQL Server query cache?

Note that neither DBCC DROPCLEANBUFFERS; nor DBCC FREEPROCCACHE; is supported in SQL Azure / SQL Data Warehouse.

However, if you need to reset the plan cache in SQL Azure, you can alter one of the tables in the query (for instance, just add then remove a column), this will have the side-effect of removing the plan from the cache.

I personally do this as a way of testing query performance without having to deal with cached plans.

More details about SQL Azure Procedure Cache here

Can't accept license agreement Android SDK Platform 24

I'm not exactly sure how cordova works, but once the licenses are accepted it creates a file. You could create that file manually. It is described on this question, but here's the commands to create the required license file.

Linux:

mkdir "$ANDROID_HOME/licenses"
echo -e "\n8933bad161af4178b1185d1a37fbf41ea5269c55" > "$ANDROID_HOME/licenses/android-sdk-license"

Windows:

mkdir "%ANDROID_HOME%\licenses"
echo |set /p="8933bad161af4178b1185d1a37fbf41ea5269c55" > "%ANDROID_HOME%\licenses\android-sdk-license"

How does the FetchMode work in Spring Data JPA

"FetchType.LAZY" will only fire for primary table. If in your code you call any other method that has a parent table dependency then it will fire query to get that table information. (FIRES MULTIPLE SELECT)

"FetchType.EAGER" will create join of all table including relevant parent tables directly. (USES JOIN)

When to Use: Suppose you compulsorily need to use dependant parent table informartion then choose FetchType.EAGER. If you only need information for certain records then use FetchType.LAZY.

Remember, FetchType.LAZY needs an active db session factory at the place in your code where if you choose to retrieve parent table information.

E.g. for LAZY:

.. Place fetched from db from your dao loayer
.. only place table information retrieved
.. some code
.. getCity() method called... Here db request will be fired to get city table info

Additional reference

How to remove white space characters from a string in SQL Server

Looks like the invisible character -

ALT+255

Try this

select REPLACE(ProductAlternateKey, ' ', '@')
--type ALT+255 instead of space for the second expression in REPLACE 
from DimProducts
where ProductAlternateKey  like '46783815%'

Raj

Edit: Based on ASCII() results, try ALT+10 - use numeric keypad

Integrating CSS star rating into an HTML form

This is very easy to use, just copy-paste the code. You can use your own star image in background.

I have created a variable var userRating. you can use this variable to get value from stars.

Enjoy!! :)

_x000D_
_x000D_
$(document).ready(function(){_x000D_
    // Check Radio-box_x000D_
    $(".rating input:radio").attr("checked", false);_x000D_
_x000D_
    $('.rating input').click(function () {_x000D_
        $(".rating span").removeClass('checked');_x000D_
        $(this).parent().addClass('checked');_x000D_
    });_x000D_
_x000D_
    $('input:radio').change(_x000D_
      function(){_x000D_
        var userRating = this.value;_x000D_
        alert(userRating);_x000D_
    }); _x000D_
});
_x000D_
.rating {_x000D_
    float:left;_x000D_
    width:300px;_x000D_
}_x000D_
.rating span { float:right; position:relative; }_x000D_
.rating span input {_x000D_
    position:absolute;_x000D_
    top:0px;_x000D_
    left:0px;_x000D_
    opacity:0;_x000D_
}_x000D_
.rating span label {_x000D_
    display:inline-block;_x000D_
    width:30px;_x000D_
    height:30px;_x000D_
    text-align:center;_x000D_
    color:#FFF;_x000D_
    background:#ccc;_x000D_
    font-size:30px;_x000D_
    margin-right:2px;_x000D_
    line-height:30px;_x000D_
    border-radius:50%;_x000D_
    -webkit-border-radius:50%;_x000D_
}_x000D_
.rating span:hover ~ span label,_x000D_
.rating span:hover label,_x000D_
.rating span.checked label,_x000D_
.rating span.checked ~ span label {_x000D_
    background:#F90;_x000D_
    color:#FFF;_x000D_
}
_x000D_
<script src="https://ajax.googleapis.com/ajax/libs/jquery/2.1.1/jquery.min.js"></script>_x000D_
<div class="rating">_x000D_
    <span><input type="radio" name="rating" id="str5" value="5"><label for="str5"></label></span>_x000D_
    <span><input type="radio" name="rating" id="str4" value="4"><label for="str4"></label></span>_x000D_
    <span><input type="radio" name="rating" id="str3" value="3"><label for="str3"></label></span>_x000D_
    <span><input type="radio" name="rating" id="str2" value="2"><label for="str2"></label></span>_x000D_
    <span><input type="radio" name="rating" id="str1" value="1"><label for="str1"></label></span>_x000D_
</div>
_x000D_
_x000D_
_x000D_

ASP.NET MVC 3 Razor - Adding class to EditorFor

I just needed to set the size of one textbox on one page. Coding attributes on the model and creating custom editor templates were overkill, so I just wrapped the @Html.EditorFor call with a span tag that called a class which specifies the size of the textbox.

CSS class declaration:

.SpaceAvailableSearch input
{
    width:25px;
}

View code:

<span class="SpaceAvailableSearch">@Html.EditorFor(model => model.SearchForm.SpaceAvailable)</span>

What is the use of "assert"?

Python assert is basically a debugging aid which test condition for internal self-check of your code. Assert makes debugging really easy when your code gets into impossible edge cases. Assert check those impossible cases.

Let's say there is a function to calculate price of item after discount :

def calculate_discount(price, discount):
    discounted_price = price - [discount*price]
    assert 0 <= discounted_price <= price
    return discounted_price

here, discounted_price can never be less than 0 and greater than actual price. So, in case the above condition is violated assert raises an Assertion Error, which helps the developer to identify that something impossible had happened.

Hope it helps :)

Python threading. How do I lock a thread?

You can see that your locks are pretty much working as you are using them, if you slow down the process and make them block a bit more. You had the right idea, where you surround critical pieces of code with the lock. Here is a small adjustment to your example to show you how each waits on the other to release the lock.

import threading
import time
import inspect

class Thread(threading.Thread):
    def __init__(self, t, *args):
        threading.Thread.__init__(self, target=t, args=args)
        self.start()

count = 0
lock = threading.Lock()

def incre():
    global count
    caller = inspect.getouterframes(inspect.currentframe())[1][3]
    print "Inside %s()" % caller
    print "Acquiring lock"
    with lock:
        print "Lock Acquired"
        count += 1  
        time.sleep(2)  

def bye():
    while count < 5:
        incre()

def hello_there():
    while count < 5:
        incre()

def main():    
    hello = Thread(hello_there)
    goodbye = Thread(bye)


if __name__ == '__main__':
    main()

Sample output:

...
Inside hello_there()
Acquiring lock
Lock Acquired
Inside bye()
Acquiring lock
Lock Acquired
...

How to sort two lists (which reference each other) in the exact same way

If you are using numpy you can use np.argsort to get the sorted indices and apply those indices to the list. This works for any number of list that you would want to sort.

import numpy as np

arr1 = np.array([4,3,1,32,21])
arr2 = arr1 * 10
sorted_idxs = np.argsort(arr1)

print(sorted_idxs)
>>> array([2, 1, 0, 4, 3])

print(arr1[sorted_idxs])
>>> array([ 1,  3,  4, 21, 32])

print(arr2[sorted_idxs])
>>> array([ 10,  30,  40, 210, 320])

Import regular CSS file in SCSS file?

Simple.

@import "path/to/file.css";

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

I need to do something like this I ended up going with the following solution.

I have a specific website URL that will open a page with two buttons

1) Button One go to website

2) Button Two go to application (iphone / android phone / tablet) you can fall back to a default location from here if the app is not installed (like another url or an app store)

3) cookie to remember users choice

<head>
<title>Mobile Router Example </title>


<script type="text/javascript">
    function set_cookie(name,value)
    {
       // js code to write cookie
    }
    function read_cookie(name) {
       // jsCode to read cookie
    }

    function goToApp(appLocation) {
        setTimeout(function() {
            window.location = appLocation;
              //this is a fallback if the app is not installed. Could direct to an app store or a website telling user how to get app


        }, 25);
        window.location = "custom-uri://AppShouldListenForThis";
    }

    function goToWeb(webLocation) {
        window.location = webLocation;
    }

    if (readCookie('appLinkIgnoreWeb') == 'true' ) {
        goToWeb('http://somewebsite');

    }
    else if (readCookie('appLinkIgnoreApp') == 'true') {
        goToApp('http://fallbackLocation');
    }



</script>
</head>
<body>


<div class="iphone_table_padding">
<table border="0" cellspacing="0" cellpadding="0" style="width:100%;">
    <tr>
        <td class="iphone_table_leftRight">&nbsp;</td>
        <td>
            <!-- INTRO -->
            <span class="iphone_copy_intro">Check out our new app or go to website</span>
        </td>
        <td class="iphone_table_leftRight">&nbsp;</td>
    </tr>
    <tr>
        <td class="iphone_table_leftRight">&nbsp;</td>
        <td>
            <div class="iphone_btn_padding">

                <!-- GET IPHONE APP BTN -->
                <table border="0" cellspacing="0" cellpadding="0" class="iphone_btn" onclick="set_cookie('appLinkIgnoreApp',document.getElementById('chkDontShow').checked);goToApp('http://getappfallback')">
                    <tr>
                        <td class="iphone_btn_on_left">&nbsp;</td>
                        <td class="iphone_btn_on_mid">
                            <span class="iphone_copy_btn">
                                Get The Mobile Applications
                            </span>
                        </td>
                        <td class="iphone_btn_on_right">&nbsp;</td>
                    </tr>
                </table>

            </div>
        </td>
        <td class="iphone_table_leftRight">&nbsp;</td>
    </tr>
    <tr>
        <td class="iphone_table_leftRight">&nbsp;</td>
        <td>
            <div class="iphone_btn_padding">

                <table border="0" cellspacing="0" cellpadding="0" class="iphone_btn"  onclick="set_cookie('appLinkIgnoreWeb',document.getElementById('chkDontShow').checked);goToWeb('http://www.website.com')">
                    <tr>
                        <td class="iphone_btn_left">&nbsp;</td>
                        <td class="iphone_btn_mid">
                            <span class="iphone_copy_btn">
                                Visit Website.com
                            </span>
                        </td>
                        <td class="iphone_btn_right">&nbsp;</td>
                    </tr>
                </table>

            </div>
        </td>
        <td class="iphone_table_leftRight">&nbsp;</td>
    </tr>
    <tr>
        <td class="iphone_table_leftRight">&nbsp;</td>
        <td>
            <div class="iphone_chk_padding">

                <!-- CHECK BOX -->
                <table border="0" cellspacing="0" cellpadding="0">
                    <tr>
                        <td><input type="checkbox" id="chkDontShow" /></td>
                        <td>
                            <span class="iphone_copy_chk">
                                <label for="chkDontShow">&nbsp;Don&rsquo;t show this screen again.</label>
                            </span>
                        </td>
                    </tr>
                </table>

            </div>
        </td>
        <td class="iphone_table_leftRight">&nbsp;</td>
    </tr>
</table>

</div>

</body>
</html>

Where is Ubuntu storing installed programs?

for some applications, for example google chrome, they store it under /opt. you can follow the above instruction using dpkg -l to get the correct naming then dpkg -L to get the detail.

hope it helps

How do I find the length/number of items present for an array?

Do you mean how long is the array itself, or how many customerids are in it?

Because the answer to the first question is easy: 5 (or if you don't want to hard-code it, Ben Stott's answer).

But the answer to the other question cannot be automatically determined. Presumably you have allocated an array of length 5, but will initially have 0 customer IDs in there, and will put them in one at a time, and your question is, "how many customer IDs have I put into the array?"

C can't tell you this. You will need to keep a separate variable, int numCustIds (for example). Every time you put a customer ID into the array, increment that variable. Then you can tell how many you have put in.

How can I search for a multiline pattern in a file?

@Marcin: awk example non-greedy:

awk '{if ($0 ~ /Start pattern/) {triggered=1;}if (triggered) {print; if ($0 ~ /End pattern/) { exit;}}}' filename

Merge two (or more) lists into one, in C# .NET

I know this is an old question I thought I might just add my 2 cents.

If you have a List<Something>[] you can join them using Aggregate

public List<TType> Concat<TType>(params List<TType>[] lists)
{
    var result = lists.Aggregate(new List<TType>(), (x, y) => x.Concat(y).ToList());

    return result;
}

Hope this helps.

How do I delete everything below row X in VBA/Excel?

Another option is Sheet1.Rows(x & ":" & Sheet1.Rows.Count).ClearContents (or .Clear). The reason you might want to use this method instead of .Delete is because any cells with dependencies in the deleted range (e.g. formulas that refer to those cells, even if empty) will end up showing #REF. This method will preserve formula references to the cleared cells.

importing go files in same folder

./main.go (in package main)
./a/a.go (in package a)
./a/b.go (in package a)

in this case:
main.go import "./a"

It can call the function in the a.go and b.go,that with first letter caps on.

Bulk insert with SQLAlchemy ORM

The sqlalchemy docs have a writeup on the performance of various techniques that can be used for bulk inserts:

ORMs are basically not intended for high-performance bulk inserts - this is the whole reason SQLAlchemy offers the Core in addition to the ORM as a first-class component.

For the use case of fast bulk inserts, the SQL generation and execution system that the ORM builds on top of is part of the Core. Using this system directly, we can produce an INSERT that is competitive with using the raw database API directly.

Alternatively, the SQLAlchemy ORM offers the Bulk Operations suite of methods, which provide hooks into subsections of the unit of work process in order to emit Core-level INSERT and UPDATE constructs with a small degree of ORM-based automation.

The example below illustrates time-based tests for several different methods of inserting rows, going from the most automated to the least. With cPython 2.7, runtimes observed:

classics-MacBook-Pro:sqlalchemy classic$ python test.py
SQLAlchemy ORM: Total time for 100000 records 12.0471920967 secs
SQLAlchemy ORM pk given: Total time for 100000 records 7.06283402443 secs
SQLAlchemy ORM bulk_save_objects(): Total time for 100000 records 0.856323003769 secs
SQLAlchemy Core: Total time for 100000 records 0.485800027847 secs
sqlite3: Total time for 100000 records 0.487842082977 sec

Script:

import time
import sqlite3

from sqlalchemy.ext.declarative import declarative_base
from sqlalchemy import Column, Integer, String,  create_engine
from sqlalchemy.orm import scoped_session, sessionmaker

Base = declarative_base()
DBSession = scoped_session(sessionmaker())
engine = None


class Customer(Base):
    __tablename__ = "customer"
    id = Column(Integer, primary_key=True)
    name = Column(String(255))


def init_sqlalchemy(dbname='sqlite:///sqlalchemy.db'):
    global engine
    engine = create_engine(dbname, echo=False)
    DBSession.remove()
    DBSession.configure(bind=engine, autoflush=False, expire_on_commit=False)
    Base.metadata.drop_all(engine)
    Base.metadata.create_all(engine)


def test_sqlalchemy_orm(n=100000):
    init_sqlalchemy()
    t0 = time.time()
    for i in xrange(n):
        customer = Customer()
        customer.name = 'NAME ' + str(i)
        DBSession.add(customer)
        if i % 1000 == 0:
            DBSession.flush()
    DBSession.commit()
    print(
        "SQLAlchemy ORM: Total time for " + str(n) +
        " records " + str(time.time() - t0) + " secs")


def test_sqlalchemy_orm_pk_given(n=100000):
    init_sqlalchemy()
    t0 = time.time()
    for i in xrange(n):
        customer = Customer(id=i+1, name="NAME " + str(i))
        DBSession.add(customer)
        if i % 1000 == 0:
            DBSession.flush()
    DBSession.commit()
    print(
        "SQLAlchemy ORM pk given: Total time for " + str(n) +
        " records " + str(time.time() - t0) + " secs")


def test_sqlalchemy_orm_bulk_insert(n=100000):
    init_sqlalchemy()
    t0 = time.time()
    n1 = n
    while n1 > 0:
        n1 = n1 - 10000
        DBSession.bulk_insert_mappings(
            Customer,
            [
                dict(name="NAME " + str(i))
                for i in xrange(min(10000, n1))
            ]
        )
    DBSession.commit()
    print(
        "SQLAlchemy ORM bulk_save_objects(): Total time for " + str(n) +
        " records " + str(time.time() - t0) + " secs")


def test_sqlalchemy_core(n=100000):
    init_sqlalchemy()
    t0 = time.time()
    engine.execute(
        Customer.__table__.insert(),
        [{"name": 'NAME ' + str(i)} for i in xrange(n)]
    )
    print(
        "SQLAlchemy Core: Total time for " + str(n) +
        " records " + str(time.time() - t0) + " secs")


def init_sqlite3(dbname):
    conn = sqlite3.connect(dbname)
    c = conn.cursor()
    c.execute("DROP TABLE IF EXISTS customer")
    c.execute(
        "CREATE TABLE customer (id INTEGER NOT NULL, "
        "name VARCHAR(255), PRIMARY KEY(id))")
    conn.commit()
    return conn


def test_sqlite3(n=100000, dbname='sqlite3.db'):
    conn = init_sqlite3(dbname)
    c = conn.cursor()
    t0 = time.time()
    for i in xrange(n):
        row = ('NAME ' + str(i),)
        c.execute("INSERT INTO customer (name) VALUES (?)", row)
    conn.commit()
    print(
        "sqlite3: Total time for " + str(n) +
        " records " + str(time.time() - t0) + " sec")

if __name__ == '__main__':
    test_sqlalchemy_orm(100000)
    test_sqlalchemy_orm_pk_given(100000)
    test_sqlalchemy_orm_bulk_insert(100000)
    test_sqlalchemy_core(100000)
    test_sqlite3(100000)

Comparing arrays in JUnit assertions, concise built-in way?

I prefer to convert arrays to strings:

Assert.assertEquals(
                Arrays.toString(values),
                Arrays.toString(new int[] { 7, 8, 9, 3 }));

this way I can see clearly where wrong values are. This works effectively only for small sized arrays, but I rarely use arrays with more items than 7 in my unit tests.

This method works for primitive types and for other types when overload of toString returns all essential information.

Java properties UTF-8 encoding in Eclipse

There is much easier way:

props.load(new InputStreamReader(new FileInputStream("properties_file"), "UTF8"));

How to do parallel programming in Python?

You can use the multiprocessing module. For this case I might use a processing pool:

from multiprocessing import Pool
pool = Pool()
result1 = pool.apply_async(solve1, [A])    # evaluate "solve1(A)" asynchronously
result2 = pool.apply_async(solve2, [B])    # evaluate "solve2(B)" asynchronously
answer1 = result1.get(timeout=10)
answer2 = result2.get(timeout=10)

This will spawn processes that can do generic work for you. Since we did not pass processes, it will spawn one process for each CPU core on your machine. Each CPU core can execute one process simultaneously.

If you want to map a list to a single function you would do this:

args = [A, B]
results = pool.map(solve1, args)

Don't use threads because the GIL locks any operations on python objects.

MySql sum elements of a column

select
  sum(a) as atotal,
  sum(b) as btotal,
  sum(c) as ctotal
from
  yourtable t
where
  t.id in (1, 2, 3)

C# Select elements in list as List of string

List<string> empnames = (from e in emplist select e.Enaame).ToList();

Or

string[] empnames = (from e in emplist select e.Enaame).ToArray();

Etc...

SELECT FOR UPDATE with SQL Server

Try using:

SELECT * FROM <tablename> WITH ROWLOCK XLOCK HOLDLOCK

This should make the lock exclusive and hold it for the duration of the transaction.

Background images: how to fill whole div if image is small and vice versa

Rather than giving background-size:100%;
We can give background-size:contain;
Check out this for different options avaliable: http://www.css3.info/preview/background-size/

Undefined index with $_POST

Use:

if (isset($_POST['user'])) {
   //do something
}

But you probably should be using some more proper validation. Try a simple regex or a rock-solid implementation from Zend Framework or Symfony.

http://framework.zend.com/manual/en/zend.validate.introduction.html

http://symfony.com/doc/current/book/validation.html

Or even the built-in filter extension:

http://php.net/manual/en/function.filter-var.php

Never trust user input, be smart. Don't trust anything. Always make sure what you receive is really what you expect. If it should be a number, make SURE it's a number.

Much improved code:

$user = filter_var($_POST['user'], FILTER_SANITIZE_STRING);
$isValid = filter_var($user, FILTER_VALIDATE_REGEXP, array('options' => array('regexp' => "/^[a-zA-Z0-9]+$/")));

if ($isValid) {
    // do something
}

Sanitization and validation.

How to access Session variables and set them in javascript?

If you want read Session value in javascript.This code help for you.

<script type='text/javascript'> var userID='@Session["userID"]'; </script>

How can I solve Exception in thread "main" java.lang.NullPointerException error

This is the problem

double a[] = null;

Since a is null, NullPointerException will arise every time you use it until you initialize it. So this:

a[i] = var;

will fail.

A possible solution would be initialize it when declaring it:

double a[] = new double[PUT_A_LENGTH_HERE]; //seems like this constant should be 7

IMO more important than solving this exception, is the fact that you should learn to read the stacktrace and understand what it says, so you could detect the problems and solve it.

java.lang.NullPointerException

This exception means there's a variable with null value being used. How to solve? Just make sure the variable is not null before being used.

at twoten.TwoTenB.(TwoTenB.java:29)

This line has two parts:

  • First, shows the class and method where the error was thrown. In this case, it was at <init> method in class TwoTenB declared in package twoten. When you encounter an error message with SomeClassName.<init>, means the error was thrown while creating a new instance of the class e.g. executing the constructor (in this case that seems to be the problem).
  • Secondly, shows the file and line number location where the error is thrown, which is between parenthesis. This way is easier to spot where the error arose. So you have to look into file TwoTenB.java, line number 29. This seems to be a[i] = var;.

From this line, other lines will be similar to tell you where the error arose. So when reading this:

at javapractice.JavaPractice.main(JavaPractice.java:32)

It means that you were trying to instantiate a TwoTenB object reference inside the main method of your class JavaPractice declared in javapractice package.

How to shuffle an ArrayList

Use this method and pass your array in parameter

Collections.shuffle(arrayList);

This method return void so it will not give you a new list but as we know that array is passed as a reference type in Java so it will shuffle your array and save shuffled values in it. That's why you don't need any return type.

You can now use arraylist which is shuffled.

What are the differences between the different saving methods in Hibernate?

I found a good example showing the differences between all hibernate save methods:

http://www.journaldev.com/3481/hibernate-session-merge-vs-update-save-saveorupdate-persist-example

In brief, according to the above link:

save()

  • We can invoke this method outside a transaction. If we use this without transaction and we have cascading between entities, then only the primary entity gets saved unless we flush the session.
  • So, if there are other objects mapped from the primary object, they gets saved at the time of committing transaction or when we flush the session.

persist()

  • Its similar to using save() in transaction, so it’s safe and takes care of any cascaded objects.

saveOrUpdate()

  • Can be used with or without the transaction, and just like save(), if its used without the transaction, mapped entities wont be saved un;ess we flush the session.

  • Results into insert or update queries based on the provided data. If the data is present in the database, update query is executed.

update()

  • Hibernate update should be used where we know that we are only updating the entity information. This operation adds the entity object to persistent context and further changes are tracked and saved when transaction is committed.
  • Hence even after calling update, if we set any values in the entity,they will be updated when transaction commits.

merge()

  • Hibernate merge can be used to update existing values, however this method create a copy from the passed entity object and return it. The returned object is part of persistent context and tracked for any changes, passed object is not tracked. This is the major difference with merge() from all other methods.

Also for practical examples of all these, please refer to the link I mentioned above, it shows examples for all these different methods.

How to use an arraylist as a prepared statement parameter

If you have ArrayList then convert into Array[Object]

ArrayList<String> list = new ArrayList<String>();
PreparedStatement pstmt = 
            conn.prepareStatement("select * from employee where id in (?)");
Array array = conn.createArrayOf("VARCHAR", list.toArray());
pstmt.setArray(1, array);
ResultSet rs = pstmt.executeQuery();

downcast and upcast

Upcasting and Downcasting:

Upcasting: Casting from Derived-Class to Base Class Downcasting: Casting from Base Class to Derived Class

Let's understand the same as an example:

Consider two classes Shape as My parent class and Circle as a Derived class, defined as follows:

class Shape
{
    public int Width { get; set; }
    public int Height { get; set; }
}

class Circle : Shape
{
    public int Radius { get; set; }
    public bool FillColor { get; set; }
}

Upcasting:

Shape s = new Shape();

Circle c= s;

Both c and s are referencing to the same memory location, but both of them have different views i.e using "c" reference you can access all the properties of the base class and derived class as well but using "s" reference you can access properties of the only parent class.

A practical example of upcasting is Stream class which is baseclass of all types of stream reader of .net framework:

StreamReader reader = new StreamReader(new FileStreamReader());

here, FileStreamReader() is upcasted to streadm reder.

Downcasting:

Shape s = new Circle(); here as explained above, view of s is the only parent, in order to make it for both parent and a child we need to downcast it

var c = (Circle) s;

The practical example of Downcasting is button class of WPF.

plot legends without border and with white background

Use option bty = "n" in legend to remove the box around the legend. For example:

legend(1, 5,
       "This legend text should not be disturbed by the dotted grey lines,\nbut the plotted dots should still be visible",
       bty = "n")

How do I configure different environments in Angular.js?

If you're using Brunch, the plugin Constangular helps you to manage variables for different environments.

Return row of Data Frame based on value in a column - R

Use which.min:

df <- data.frame(Name=c('A','B','C','D'), Amount=c(150,120,175,160))
df[which.min(df$Amount),]

> df[which.min(df$Amount),]
  Name Amount
2    B    120

From the help docs:

Determines the location, i.e., index of the (first) minimum or maximum of a numeric (or logical) vector.

Highlight the difference between two strings in PHP

What you are looking for is a "diff algorithm". A quick google search led me to this solution. I did not test it, but maybe it will do what you need.

Pylint, PyChecker or PyFlakes?

pep8 was recently added to PyPi.

  • pep8 - Python style guide checker
  • pep8 is a tool to check your Python code against some of the style conventions in PEP 8.

It is now super easy to check your code against pep8.

See http://pypi.python.org/pypi/pep8

What is the JavaScript version of sleep()?

Adding my two bits. I needed a busy-wait for testing purposes. I didn't want to split the code as that would be a lot of work, so a simple for did it for me.

for (var i=0;i<1000000;i++){                    
     //waiting
  }

I don't see any downside in doing this and it did the trick for me.

Response Buffer Limit Exceeded

Thank you so much! <%Response.Buffer = False%> worked like a charm! My asp/HTML table that was returning a blank page at about 2700 records. The following debugging lines helped expose the buffering problem: I replace the Do While loop as follows and played with my limit numbers to see what was happening:

Replace

Do While not rs.EOF

'etc .... your block of code that writes the table rows

rs.moveNext

Loop

with

Do While reccount < 2500

if rs.EOF then recount = 2501

'etc .... your block of code that writes the table rows

rs.moveNext

Loop

response.write "recount = " & recount

raise or lower the 2500 and 2501 to see if it is a buffer problem. for my record set, I could see that the blank page return, blank table, was happening at about 2700 records, good luck to all and thank you again for solving this problem! Such a simple great solution!

ld: framework not found Pods

Other thing that solved my problem is to go under Target -> Build Settings -> Other linker Flags and delete the "-framework" and your framework "name".

It happened when i tried to remove a pod.

How to clone a Date object?

_x000D_
_x000D_
var orig = new Date();
var copy = new Date(+orig);

console.log(orig, copy);
_x000D_
_x000D_
_x000D_

How to replace url parameter with javascript/jquery?

Wouldn't this be a better solution?

var text = 'http://localhost/mysite/includes/phpThumb.php?src=http://media2.jupix.co.uk/v3/clients/4/properties/795/IMG_795_1_large.jpg&w=592&aoe=1&q=100';
var newSrc = 'www.google.com';
var newText = text.replace(/(src=).*?(&)/,'$1' + newSrc + '$2');

EDIT:

added some clarity in code and kept 'src' in the resulting link

$1 represents first part within the () (i.e) src= and $2 represents the second part within the () (i.e) &, so this indicates you are going to change the value between src and &. More clear, it should be like this:

src='changed value'& // this is to be replaced with your original url

ADD-ON for replacing all the ocurrences:

If you have several parameters with the same name, you can append to the regex global flag, like this text.replace(/(src=).*?(&)/g,'$1' + newSrc + '$2'); and that will replaces all the values for those params that shares the same name.

What is setup.py?

To make it simple, setup.py is run as "__main__" when you call the install functions the other answers mentioned. Inside setup.py, you should put everything needed to install your package.

Common setup.py functions

The following two sections discuss two things many setup.py modules have.

setuptools.setup

This function allows you to specify project attributes like the name of the project, the version.... Most importantly, this function allows you to install other functions if they're packaged properly. See this webpage for an example of setuptools.setup

These attributes of setuptools.setup enable installing these types of packages:

  • Packages that are imported to your project and listed in PyPI using setuptools.findpackages:

    packages=find_packages(exclude=["docs","tests", ".gitignore", "README.rst","DESCRIPTION.rst"])

  • Packages not in PyPI, but can be downloaded from a URL using dependency_links

    dependency_links=["http://peak.telecommunity.com/snapshots/",]

Custom functions

In an ideal world, setuptools.setup would handle everything for you. Unfortunately this isn't always the case. Sometimes you have to do specific things, like installing dependencies with the subprocess command, to get the system you're installing on in the right state for your package. Try to avoid this, these functions get confusing and often differ between OS and even distribution.

Making HTML page zoom by default

In js you can change zoom by

document.body.style.zoom="90%"

But it doesn't work in FF http://caniuse.com/#search=zoom

For ff you can try

-moz-transform: scale(0.9);

And check next topic How can I zoom an HTML element in Firefox and Opera?

ant warning: "'includeantruntime' was not set"

i faced this same, i check in in program and feature. there was an update has install for jdk1.8 which is not compatible with my old setting(jdk1.6.0) for ant in eclipse. I install that update. right now, my ant project is build success.

Try it, hope this will be helpful.

How to uninstall / completely remove Oracle 11g (client)?

Assuming a Windows installation, do please refer to this:

http://www.oracle-base.com/articles/misc/ManualOracleUninstall.php

  • Uninstall all Oracle components using the Oracle Universal Installer (OUI).
  • Run regedit.exe and delete the HKEY_LOCAL_MACHINE\SOFTWARE\ORACLE key. This contains registry entires for all Oracle products.
  • Delete any references to Oracle services left behind in the following part of the registry: HKEY_LOCAL_MACHINE\SYSTEM\CurrentControlSet\Services\Ora* It should be pretty obvious which ones relate to Oracle.
  • Reboot your machine.
  • Delete the "C:\Oracle" directory, or whatever directory is your ORACLE_BASE.
  • Delete the "C:\Program Files\Oracle" directory.
  • Empty the contents of your "C:\temp" directory.
  • Empty your recycle bin.

Calling additional attention to some great comments that were left here:

  • Be careful when following anything listed here (above or below), as doing so may remove or damage any other Oracle-installed products.
  • For 64-bit Windows (x64), you need also to delete the HKEY_LOCAL_MACHINE\SOFTWARE\Wow6432Node\ORACLE key from the registry.
  • Clean-up by removing any related shortcuts that were installed to the Start Menu.
  • Clean-up environment variables:
    • Consider removing %ORACLE_HOME%.
    • Remove any paths no longer needed from %PATH%.

This set of instructions happens to match an almost identical process that I had reverse-engineered myself over the years after a few messed-up Oracle installs, and has almost always met the need.

Note that even if the OUI is no longer available or doesn't work, simply following the remaining steps should still be sufficient.

(Revision #7 reverted as to not misquote the original source, and to not remove credit to the other comments that contributed to the answer. Further edits are appreciated (and then please remove this comment), if a way can be found to maintain these considerations.)

SQL server 2008 backup error - Operating system error 5(failed to retrieve text for this error. Reason: 15105)

I've got the same error. I have been trying to fixing this by setting higher permission to account running SQL Client service, however it didnt help. The problem was that I run MS Sql Management studio just within my account. So, next time... assure that you are running it as Run as Administrator, if using Win7 with UAC enabled.

how to overwrite css style

Yes, you can indeed. There are three ways of achieving this that I can think of.

  1. Add inline styles to the elements.
  2. create and append a new <style> element, and add the text to override this style to it.
  3. Modify the css rule itself.

Notes:

  1. is somewhat messy and adds to the parsing the browser needs to do to render.
  2. perhaps my favourite method
  3. Not cross-browser, some browsers like it done one way, others a different way, while the remainder just baulk at the idea.

Get value from hashmap based on key to JSTL

could you please try below code

<c:forEach var="hash" items="${map['key']}">
        <option><c:out value="${hash}"/></option>
  </c:forEach>

Delete the last two characters of the String

You may use the following method to remove last n character -

public String removeLast(String s, int n) {
    if (null != s && !s.isEmpty()) {
        s = s.substring(0, s.length()-n);
    }
    return s;
}

rmagick gem install "Can't find Magick-config"

imagemagick@6 works for me!

brew unlink imagemagick
brew install imagemagick@6 && brew link imagemagick@6 --force

See this thread

Android WebView Cookie Problem

My working code

public View onCreateView(...){
    mWebView = (WebView) view.findViewById(R.id.webview);

    WebSettings webSettings = mWebView.getSettings();
    webSettings.setJavaScriptEnabled(true);

        ...
        ...
        ...

    CookieSyncManager.createInstance(mWebView.getContext());
    CookieManager cookieManager = CookieManager.getInstance();
    cookieManager.setAcceptCookie(true);
    //cookieManager.removeSessionCookie(); // remove
    cookieManager.removeAllCookie(); //remove
    // Recommended "hack" with a delay between the removal and the installation of "Cookies"
    SystemClock.sleep(1000);

    cookieManager.setCookie("https://my.app.site.com/", "cookiename=" + value + "; path=/registration" + "; secure"); // ;
    CookieSyncManager.getInstance().sync();

    mWebView.loadUrl(sp.getString("url", "") + end_url);

    return view;
}

To debug the query, "cookieManager.setCookie (....);" I recommend you to look through the contents of the database webviewCookiesChromium.db (stored in "/data/data/my.app.webview/database") There You can see the correct settings.

Disabling "cookieManager.removeSessionCookie();" and/or "cookieManager.removeAllCookie();"

//cookieManager.removeSessionCookie();
// and/or
//cookieManager.removeAllCookie();"

Compare the set value with those that are set by the browser. Adjust the request for the installation of the cookies before until "flags" browser is not installed will fit with what You decide. I found that a query can be "flags":

// You may want to add the secure flag for https:
+ "; secure"
// In case you wish to convert session cookies to have an expiration:
+ "; expires=Thu, 01-Jan-2037 00:00:10 GMT"
// These flags I found in the database:
+ "; path=/registration"
+ "; domain=my.app.site.com"

Disabling Controls in Bootstrap

also you can use "readonly"

<select id="xxx" name="xxx" class="input-medium" readonly>

Appending the same string to a list of strings in Python

Here is a simple answer using pandas.

import pandas as pd
list1 = ['foo', 'fob', 'faz', 'funk']
string = 'bar'

list2 = (pd.Series(list1) + string).tolist()
list2
# ['foobar', 'fobbar', 'fazbar', 'funkbar']

How can I join on a stored procedure?

Your stored procedure could easily be used as a view instead. Then you can join it on to anything else you need.

SQL:

CREATE VIEW vwTenantBalance
AS

 SELECT tenant.ID AS TenantID, SUM(ISNULL(trans.Amount,0)) AS TenantBalance 
 FROM tblTenant tenant
 LEFT JOIN tblTransaction trans
 ON tenant.ID = trans.TenantID
 GROUP BY tenant.ID

The you can do any statement like:

SELECT t.TenantName, t.CarPlateNumber, t.CarColor, t.Sex, t.SSNO, t.Phone, 
    t.Memo, u.UnitNumber, p.PropertyName, TenantBalance
FROM tblTenant t
LEFT JOIN tblRentalUnit u
 ON t.UnitID = u.ID
LEFT JOIN tblProperty p
 ON u.PropertyID = p.ID
LEFT JOIN vwTenantBalance v 
 ON t.ID = v.tenantID
ORDER BY p.PropertyName, t.CarPlateNumber

How to Logout of an Application Where I Used OAuth2 To Login With Google?

this code will work to sign out

    <script>
      function signOut() 
      {
        var auth2 = gapi.auth2.getAuthInstance();
        auth2.signOut().then(function () {   
        console.log('User signed out.');   
        auth2.disconnect();   
      }); 
        auth2.disconnect();
      } 
    </script>

close fancy box from function from within open 'fancybox'

to close fancybox by funciton its necessary to make setTimtout to the function that will close the fancybox Fancybox needs some time to acept the close function If you call the function directly will not work

function close_fancybox(){
$.fancybox.close();
                     }
setTimeout(close_fancybox, 50);

How to round up with excel VBA round()?

Try the RoundUp function:

Dim i As Double

i = Application.WorksheetFunction.RoundUp(Cells(1, 1).Value * Cells(1, 2).Value, 2)

OS X Terminal UTF-8 issues

To make nano work as you want it to, try:

export LANG="UTF-8"

Or get a newer version of nano via MacPorts:

# cf. http://www.macports.org/install.php
port info nano
port variants nano
sudo port install nano +utf8 +color +no_wrap

With respect to ssh & UTF-8 issues comment out SendEnv LANG LC_* in /etc/ssh_config.

See: Terminal in OS X Lion: can't write åäö on remote machine

What is the recommended way to delete a large number of items from DynamoDB?

According to the DynamoDB documentation you could just delete the full table.

See below:

"Deleting an entire table is significantly more efficient than removing items one-by-one, which essentially doubles the write throughput as you do as many delete operations as put operations"

If you wish to delete only a subset of your data, then you could make separate tables for each month, year or similar. This way you could remove "last month" and keep the rest of your data intact.

This is how you delete a table in Java using the AWS SDK:

DeleteTableRequest deleteTableRequest = new DeleteTableRequest()
  .withTableName(tableName);
DeleteTableResult result = client.deleteTable(deleteTableRequest);

URL string format for connecting to Oracle database with JDBC

The correct format for url can be one of the following formats:

jdbc:oracle:thin:@<hostName>:<portNumber>:<sid>;  (if you have sid)
jdbc:oracle:thin:@//<hostName>:<portNumber>/serviceName; (if you have oracle service name)

And don't put any space there. Try to use 1521 as port number. sid (database name) must be the same as the one which is in environment variables (if you are using windows).

SQL Server Error : String or binary data would be truncated

this type of error generally occurs when you have to put characters or values more than that you have specified in Database table like in this case: you specify transaction_status varchar(10) but you actually trying to store
_transaction_status which contain 19 characters. that's why you faced this type of error in this code..

Converting integer to digit list

you can use:

First convert the value in a string to iterate it, Them each value can be convert to a Integer value = 12345

l = [ int(item) for item in str(value) ]

How to set a value of a variable inside a template code?

In your template you can do like this:

{% jump_link as name %}
{% for obj in name %}
    <div>{{obj.helo}} - {{obj.how}}</div>
{% endfor %}

In your template-tags you can add a tag like this:

@register.assignment_tag
def jump_link():
    listArr = []
    for i in range(5):
        listArr.append({"helo" : i,"how" : i})
    return listArr

SQL Server Insert Example

To insert a single row of data:

INSERT INTO USERS
VALUES (1, 'Mike', 'Jones');

To do an insert on specific columns (as opposed to all of them) you must specify the columns you want to update.

INSERT INTO USERS (FIRST_NAME, LAST_NAME)
VALUES ('Stephen', 'Jiang');

To insert multiple rows of data in SQL Server 2008 or later:

INSERT INTO USERS VALUES
(2, 'Michael', 'Blythe'),
(3, 'Linda', 'Mitchell'),
(4, 'Jillian', 'Carson'),
(5, 'Garrett', 'Vargas');

To insert multiple rows of data in earlier versions of SQL Server, use "UNION ALL" like so:

INSERT INTO USERS (FIRST_NAME, LAST_NAME)
SELECT 'James', 'Bond' UNION ALL
SELECT 'Miss', 'Moneypenny' UNION ALL
SELECT 'Raoul', 'Silva'

Note, the "INTO" keyword is optional in INSERT queries. Source and more advanced querying can be found here.

Linux c++ error: undefined reference to 'dlopen'

I met the same problem even using -ldl.

Besides this option, source files need to be placed before libraries, see undefined reference to `dlopen'.

Input text dialog Android

If you want some space at left and right of input view, you can add some padding like

private fun showAlertWithTextInputLayout(context: Context) {
    val textInputLayout = TextInputLayout(context)
    textInputLayout.setPadding(
        resources.getDimensionPixelOffset(R.dimen.dp_19), // if you look at android alert_dialog.xml, you will see the message textview have margin 14dp and padding 5dp. This is the reason why I use 19 here
        0,
        resources.getDimensionPixelOffset(R.dimen.dp_19),
        0
    )
    val input = EditText(context)
    textInputLayout.hint = "Email"
    textInputLayout.addView(input)

    val alert = AlertDialog.Builder(context)
        .setTitle("Reset Password")
        .setView(textInputLayout)
        .setMessage("Please enter your email address")
        .setPositiveButton("Submit") { dialog, _ ->
            // do some thing with input.text
            dialog.cancel()
        }
        .setNegativeButton("Cancel") { dialog, _ ->
            dialog.cancel()
        }.create()

    alert.show()
}

dimens.xml

<dimen name="dp_19">19dp</dimen>

Hope it help

How to get the last five characters of a string using Substring() in C#?

simple way to do this in one line of code would be this

string sub = input.Substring(input.Length > 5 ? input.Length - 5 : 0);

and here some informations about Operator ? :

AngularJS: factory $http.get JSON file

I have approximately these problem. I need debug AngularJs application from Visual Studio 2013.

By default IIS Express restricted access to local files (like json).

But, first: JSON have JavaScript syntax.

Second: javascript files is allowed.

So:

  1. rename JSON to JS (data.json->data.js).

  2. correct load command ($http.get('App/data.js').success(function (data) {...

  3. load script data.js to page (<script src="App/data.js"></script>)

Next use loaded data an usual manner. It is just workaround, of course.

font awesome icon in select option

You can simply add a FontAwesome icon to your select dropdown as text. You only need a few things in CSS only, the FontAwesome CSS and the unicode. For example &#xf26e;:

_x000D_
_x000D_
select {_x000D_
  font-family: 'FontAwesome', 'Second Font name'_x000D_
}
_x000D_
<link href="https://maxcdn.bootstrapcdn.com/font-awesome/4.6.1/css/font-awesome.min.css" rel="stylesheet"/>_x000D_
<select>_x000D_
  <option>Hi, &#xf042;</option>_x000D_
  <option>Hi, &#xf043;</option>_x000D_
  <option>Hi, &#xf044;</option>_x000D_
  <option>Hi, &#xf045;</option>_x000D_
  <option>Hi, &#xf046;</option>_x000D_
</select>
_x000D_
_x000D_
_x000D_

Working fiddle

The unicodes can be found when you click on an icon: Fontawesome

According to the comment below and issue on Github, the unicode in select elements won't work on OSX (yet).


Update: from the Github issue, adding multiple attribute to select element makes it work on:

OSX El Capitan 10.11.4

  • Chrome version 50.0.2661.75 (64-bit)
  • Sarafi version 9.1
  • Firefox version 45.0.2

_x000D_
_x000D_
select{_x000D_
  font-family: FontAwesome, sans-serif;_x000D_
}
_x000D_
<link href="https://maxcdn.bootstrapcdn.com/font-awesome/4.6.1/css/font-awesome.min.css" rel="stylesheet"/>_x000D_
<select multiple>_x000D_
  <option>&#xf26e 500px</option>_x000D_
  <option>&#xf042 Adjust</option>_x000D_
  <option>&#xf170 Adn</option>_x000D_
  <option>&#xf037 Align-center</option>_x000D_
  <option>&#xf039 Align-justify</option>_x000D_
  <option>&#xf036 Align-left</option>_x000D_
  <option>&#xf038 Align-right</option>_x000D_
</select>
_x000D_
_x000D_
_x000D_

JSFiddle

HttpClient not supporting PostAsJsonAsync method C#

Try to install in your project the NuGet Package: Microsoft.AspNet.WebApi.Client:

Install-Package Microsoft.AspNet.WebApi.Client

How to parse a CSV file using PHP

Just use the function for parsing a CSV file

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

$row = 1;
if (($handle = fopen("test.csv", "r")) !== FALSE) {
  while (($data = fgetcsv($handle, 1000, ",")) !== FALSE) {
    $num = count($data);
    echo "<p> $num fields in line $row: <br /></p>\n";
    $row++;
    for ($c=0; $c < $num; $c++) {
        echo $data[$c] . "<br />\n";
    }
  }
  fclose($handle);
}

What is the difference between JOIN and JOIN FETCH when using JPA and Hibernate

If you have @oneToOne mapping set to FetchType.LAZY and you use second query (because you need Department objects to be loaded as part of Employee objects) what Hibernate will do is, it will issue queries to fetch Department objects for every individual Employee object it fetches from DB.

Later, in the code you might access Department objects via Employee to Department single-valued association and Hibernate will not issue any query to fetch Department object for the given Employee.

Remember, Hibernate still issues queries equal to the number of Employees it has fetched. Hibernate will issue same number of queries in both above queries, if you wish to access Department objects of all Employee objects

Want to show/hide div based on dropdown box selection

Wrap the code within $(document).ready(function(){...........}); handler , also remove the ; after if

$(document).ready(function(){
    $('#purpose').on('change', function() {
      if ( this.value == '1')
      //.....................^.......
      {
        $("#business").show();
      }
      else
      {
        $("#business").hide();
      }
    });
});

Fiddle Demo

Remove special symbols and extra spaces and replace with underscore using the replace method

It was not asked precisely to remove accent (only special characters), but I needed to.

The solutions givens here works but they don’t remove accent: é, è, etc.

So, before doing epascarello’s solution, you can also do:

_x000D_
_x000D_
var newString = "développeur & intégrateur";_x000D_
_x000D_
newString = replaceAccents(newString);_x000D_
newString = newString.replace(/[^A-Z0-9]+/ig, "_");_x000D_
alert(newString);_x000D_
_x000D_
/**_x000D_
 * Replaces all accented chars with regular ones_x000D_
 */_x000D_
function replaceAccents(str) {_x000D_
  // Verifies if the String has accents and replace them_x000D_
  if (str.search(/[\xC0-\xFF]/g) > -1) {_x000D_
    str = str_x000D_
      .replace(/[\xC0-\xC5]/g, "A")_x000D_
      .replace(/[\xC6]/g, "AE")_x000D_
      .replace(/[\xC7]/g, "C")_x000D_
      .replace(/[\xC8-\xCB]/g, "E")_x000D_
      .replace(/[\xCC-\xCF]/g, "I")_x000D_
      .replace(/[\xD0]/g, "D")_x000D_
      .replace(/[\xD1]/g, "N")_x000D_
      .replace(/[\xD2-\xD6\xD8]/g, "O")_x000D_
      .replace(/[\xD9-\xDC]/g, "U")_x000D_
      .replace(/[\xDD]/g, "Y")_x000D_
      .replace(/[\xDE]/g, "P")_x000D_
      .replace(/[\xE0-\xE5]/g, "a")_x000D_
      .replace(/[\xE6]/g, "ae")_x000D_
      .replace(/[\xE7]/g, "c")_x000D_
      .replace(/[\xE8-\xEB]/g, "e")_x000D_
      .replace(/[\xEC-\xEF]/g, "i")_x000D_
      .replace(/[\xF1]/g, "n")_x000D_
      .replace(/[\xF2-\xF6\xF8]/g, "o")_x000D_
      .replace(/[\xF9-\xFC]/g, "u")_x000D_
      .replace(/[\xFE]/g, "p")_x000D_
      .replace(/[\xFD\xFF]/g, "y");_x000D_
  }_x000D_
_x000D_
  return str;_x000D_
}
_x000D_
_x000D_
_x000D_

Source: https://gist.github.com/jonlabelle/5375315

How do I update a Linq to SQL dbml file?

In the case of stored procedure update, you should delete it from the .dbml file and reinsert it again. But if the stored procedure have two paths (ex: if something; display some columns; else display some other columns), make sure the two paths have the same columns aliases!!! Otherwise only the first path columns will exist.

What EXACTLY is meant by "de-referencing a NULL pointer"?

It means

myclass *p = NULL;
*p = ...;  // illegal: dereferencing NULL pointer
... = *p;  // illegal: dereferencing NULL pointer
p->meth(); // illegal: equivalent to (*p).meth(), which is dereferencing NULL pointer

myclass *p = /* some legal, non-NULL pointer */;
*p = ...;  // Ok
... = *p;  // Ok
p->meth(); // Ok, if myclass::meth() exists

basically, almost anything involving (*p) or implicitly involving (*p), e.g. p->... which is a shorthand for (*p). ...; except for pointer declaration.

Difference between DOM parentNode and parentElement

Use .parentElement and you can't go wrong as long as you aren't using document fragments.

If you use document fragments, then you need .parentNode:

let div = document.createDocumentFragment().appendChild(document.createElement('div'));
div.parentElement // null
div.parentNode // document fragment

Also:

_x000D_
_x000D_
let div = document.getElementById('t').content.firstChild_x000D_
div.parentElement // null_x000D_
div.parentNode // document fragment
_x000D_
<template id="t"><div></div></template>
_x000D_
_x000D_
_x000D_


Apparently the <html>'s .parentNode links to the Document. This should be considered a decision phail as documents aren't nodes since nodes are defined to be containable by documents and documents can't be contained by documents.

Configuration with name 'default' not found. Android Studio

I had this issue with Jenkins. The cause: I had renamed a module module to Module. I found out that git had gotten confused somehow and kept both module and Module directories, with the contents spread between both folders. The build.gradle was kept in module but the module's name was Module so it was unable to find the default configuration.

I fixed it by backing up the contents of Module, manually deleting module folder from the repo and restoring + pushing the lost files.

Vendor code 17002 to connect to SQLDeveloper

In your case the "Vendor code 17002" is the equivalent of the ORA-12541 error: It's most likely that your listener is down, or has an improper port or service name. From the docs:

ORA-12541: TNS no listener

Cause: Listener for the source repository has not been started.

Action: Start the Listener on the machine where the source repository resides.

How to clear basic authentication details in chrome

There is no way to do this in Chrome as yet (Chrome 58)

I have found the best solution is to open the url in an Incognito window, which will force you to re-enter the basic authentication credentials.

When you want to change the credentials, close the Incognito window and launch another Incognito window.

Command not found when using sudo

Check for secure_path on sudo

[root@host ~]# sudo -V | grep 'Value to override'
Value to override user's $PATH with: /sbin:/bin:/usr/sbin:/usr/bin

If $PATH is being overridden use visudo and edit /etc/sudoers

Defaults    secure_path = /sbin:/bin:/usr/sbin:/usr/bin:/usr/local/bin

How can I detect whether an iframe is loaded?

You can try onload event as well;

var createIframe = function (src) {
        var self = this;
        $('<iframe>', {
            src: src,
            id: 'iframeId',
            frameborder: 1,
            scrolling: 'no',
            onload: function () {
                self.isIframeLoaded = true;
                console.log('loaded!');
            }
        }).appendTo('#iframeContainer');

    };

tqdm in Jupyter Notebook prints new progress bars repeatedly

If the other tips here don't work and - just like me - you're using the pandas integration through progress_apply, you can let tqdm handle it:

from tqdm.autonotebook import tqdm
tqdm.pandas()

df.progress_apply(row_function, axis=1)

The main point here lies in the tqdm.autonotebook module. As stated in their instructions for use in IPython Notebooks, this makes tqdm choose between progress bar formats used in Jupyter notebooks and Jupyter consoles - for a reason still lacking further investigations on my side, the specific format chosen by tqdm.autonotebook works smoothly in pandas, while all others didn't, for progress_apply specifically.

Sieve of Eratosthenes - Finding Primes Python

import math
def sieve(n):
    primes = [True]*n
    primes[0] = False
    primes[1] = False
    for i in range(2,int(math.sqrt(n))+1):
            j = i*i
            while j < n:
                    primes[j] = False
                    j = j+i
    return [x for x in range(n) if primes[x] == True]

jar not loaded. See Servlet Spec 2.3, section 9.7.2. Offending class: javax/servlet/Servlet.class

Maven Dependency Scope

provided : This is much like compile, but indicates you expect the JDK or a container to provide the dependency at runtime. For example, when building a web application for the Java Enterprise Edition, you would set the dependency on the Servlet API and related Java EE APIs to scope provided because the web container provides those classes. This scope is only available on the compilation and test classpath, and is not transitive.

How to add a color overlay to a background image?

Try this, it's simple and clear. I have found it from here : https://css-tricks.com/tinted-images-multiple-backgrounds/

.tinted-image {

  width: 300px;
  height: 200px;

  background: 
    /* top, transparent red */ 
    linear-gradient(
      rgba(255, 0, 0, 0.45), 
      rgba(255, 0, 0, 0.45)
    ),
    /* bottom, image */
    url(https://s3-us-west-2.amazonaws.com/s.cdpn.io/3/owl1.jpg);
}

How does the "position: sticky;" property work?

two answer here:

  1. remove overflow property from body tag

  2. set height: 100% to the body to fix the problem with overflow-y: auto

min-height: 100% not-working instead of height: 100%

Need help rounding to 2 decimal places

The System.Math.Round method uses the Double structure, which, as others have pointed out, is prone to floating point precision errors. The simple solution I found to this problem when I encountered it was to use the System.Decimal.Round method, which doesn't suffer from the same problem and doesn't require redifining your variables as decimals:

Decimal.Round(0.575, 2, MidpointRounding.AwayFromZero)

Result: 0.58

Putting text in top left corner of matplotlib plot

One solution would be to use the plt.legend function, even if you don't want an actual legend. You can specify the placement of the legend box by using the loc keyterm. More information can be found at this website but I've also included an example showing how to place a legend:

ax.scatter(xa,ya, marker='o', s=20, c="lightgreen", alpha=0.9)
ax.scatter(xb,yb, marker='o', s=20, c="dodgerblue", alpha=0.9)
ax.scatter(xc,yc marker='o', s=20, c="firebrick", alpha=1.0)
ax.scatter(xd,xd,xd, marker='o', s=20, c="goldenrod", alpha=0.9)
line1 = Line2D(range(10), range(10), marker='o', color="goldenrod")
line2 = Line2D(range(10), range(10), marker='o',color="firebrick")
line3 = Line2D(range(10), range(10), marker='o',color="lightgreen")
line4 = Line2D(range(10), range(10), marker='o',color="dodgerblue")
plt.legend((line1,line2,line3, line4),('line1','line2', 'line3', 'line4'),numpoints=1, loc=2) 

Note that because loc=2, the legend is in the upper-left corner of the plot. And if the text overlaps with the plot, you can make it smaller by using legend.fontsize, which will then make the legend smaller.

How can I get the corresponding table header (th) from a table cell (td)?

That's simple, if you reference them by index. If you want to hide the first column, you would:

Copy code

$('#thetable tr').find('td:nth-child(1),th:nth-child(1)').toggle();

The reason I first selected all table rows and then both td's and th's that were the n'th child is so that we wouldn't have to select the table and all table rows twice. This improves script execution speed. Keep in mind, nth-child() is 1 based, not 0.

What exactly is Python's file.flush() doing?

It flushes the internal buffer, which is supposed to cause the OS to write out the buffer to the file.[1] Python uses the OS's default buffering unless you configure it do otherwise.

But sometimes the OS still chooses not to cooperate. Especially with wonderful things like write-delays in Windows/NTFS. Basically the internal buffer is flushed, but the OS buffer is still holding on to it. So you have to tell the OS to write it to disk with os.fsync() in those cases.

[1] http://docs.python.org/library/stdtypes.html

Can Json.NET serialize / deserialize to / from a stream?

UPDATE: This no longer works in the current version, see below for correct answer (no need to vote down, this is correct on older versions).

Use the JsonTextReader class with a StreamReader or use the JsonSerializer overload that takes a StreamReader directly:

var serializer = new JsonSerializer();
serializer.Deserialize(streamReader);

Is there an R function for finding the index of an element in a vector?

the function Position in funprog {base} also does the job. It allows you to pass an arbitrary function, and returns the first or last match.

Position(f, x, right = FALSE, nomatch = NA_integer)

How to have a default option in Angular.js select box

I think, after the inclusion of 'track by', you can use it in ng-options to get what you wanted, like the following

 <select ng-model="somethingHere" ng-options="option.name for option in options track by option.value" ></select>

This way of doing it is better because when you want to replace the list of strings with list of objects you will just change this to

 <select ng-model="somethingHere" ng-options="object.name for option in options track by object.id" ></select>

where somethingHere is an object with the properties name and id, of course. Please note, 'as' is not used in this way of expressing the ng-options, because it will only set the value and you will not be able to change it when you are using track by

How to use a SQL SELECT statement with Access VBA

If you wish to use the bound column value, you can simply refer to the combo:

sSQL = "SELECT * FROM MyTable WHERE ID = " & Me.MyCombo

You can also refer to the column property:

sSQL = "SELECT * FROM MyTable WHERE AText = '" & Me.MyCombo.Column(1) & "'"

Dim rs As DAO.Recordset     
Set rs = CurrentDB.OpenRecordset(sSQL)

strText = rs!AText
strText = rs.Fields(1)

In a textbox:

= DlookUp("AText","MyTable","ID=" & MyCombo)

*edited

Is there a simple JavaScript slider?

Here is a simple slider object for easy to use

pagecolumn_webparts_sliders

Preferred way to create a Scala list

To create a list of string, use the following:

val l = List("is", "am", "are", "if")

Ant build failed: "Target "build..xml" does not exist"

since your ant file's name is build.xml, you should just type ant without ant build.xml. that is: > ant [enter]

Attempt to invoke virtual method 'void android.widget.Button.setOnClickListener(android.view.View$OnClickListener)' on a null object reference

 mAddTaskButton.setOnClickListener(new View.OnClickListener()

you have a click listner but you haven't initialized the mAddTaskButton with your layout binding

What is limiting the # of simultaneous connections my ASP.NET application can make to a web service?

while doing performance testing, the measure i go by is RPS, that is how many requests per second can the server serve within acceptable latency.

theoretically one server can only run as many requests concurrently as number of cores on it..

It doesn't look like the problem is ASP.net's threading model, since it can potentially serve thousands of rps. It seems like the problem might be your application. Are you using any synchronization primitives ?

also whats the latency on your web services, are they very quick to respond (within microseconds), if not then you might want to consider asynchronous calls, so you dont end up blocking

If this doesnt yeild something, then you might want to profile your code using visual studio or redgate profiler

How to change value of ArrayList element in java

Where you say you're changing the value of the first element;

x = Integer.valueOf(9);

You're changing x to point to an entirely new Integer, but never using it again. You're not changing the collection in any way.

Since you're working with ArrayList, you can use ListIterator if you want an iterator that allows you to change the elements, this is the snippet of your code that would need to be changed;

//initialize the Iterator
ListIterator<Integer> i = a.listIterator();

//changed the value of frist element in List
if(i.hasNext()) {
    i.next();
    i.set(Integer.valueOf(9));    // Change the element the iterator is currently at
}

// New iterator, and print all the elements
Iterator iter = a.iterator();
while(iter.hasNext())
    System.out.print(iter.next());

>> 912345678

Sadly the same cannot be extended to other collections like Set<T>. Implementation details (a HashSet for example being implemented as a hash table and changing the object could change the hash value and therefore the iteration order) makes Set<T> a "add new/remove only" type of data structure, and changing the content at all while iterating over it is not safe.

Git Symlinks in Windows

I was looking for an easy solution to deal with the unix symbolic links on windows. Thank you very much for the above Git aliases. There is one little optimization that can be done to the rm-symlinks so that it doesn't delete the files in the destination folder in case the alias is run a second time accidentally. Please observe the new if condition in the loop to make sure the file is not already a link to a directory before the logic is run.

git config --global alias.rm-symlinks '!__git_rm_symlinks(){
for symlink in $(git ls-files -s | egrep "^120000" | cut -f2); do
    *if [ -d "$symlink" ]; then
      continue
    fi*
    git rm-symlink "$symlink"
    git update-index --assume-unchanged "$symlink"
done
}; __git_rm_symlinksenter 

At runtime, find all classes in a Java application that extend a base class

The Java way to do what you want is to use the ServiceLoader mechanism.

Also many people roll their own by having a file in a well known classpath location (i.e. /META-INF/services/myplugin.properties) and then using ClassLoader.getResources() to enumerate all files with this name from all jars. This allows each jar to export its own providers and you can instantiate them by reflection using Class.forName()

SignalR Console app example

Example for SignalR 2.2.1 (May 2017)

Server

Install-Package Microsoft.AspNet.SignalR.SelfHost -Version 2.2.1

[assembly: OwinStartup(typeof(Program.Startup))]
namespace ConsoleApplication116_SignalRServer
{
    class Program
    {
        static IDisposable SignalR;

        static void Main(string[] args)
        {
            string url = "http://127.0.0.1:8088";
            SignalR = WebApp.Start(url);

            Console.ReadKey();
        }

        public class Startup
        {
            public void Configuration(IAppBuilder app)
            {
                app.UseCors(CorsOptions.AllowAll);

                /*  CAMEL CASE & JSON DATE FORMATTING
                 use SignalRContractResolver from
                https://stackoverflow.com/questions/30005575/signalr-use-camel-case

                var settings = new JsonSerializerSettings()
                {
                    DateFormatHandling = DateFormatHandling.IsoDateFormat,
                    DateTimeZoneHandling = DateTimeZoneHandling.Utc
                };

                settings.ContractResolver = new SignalRContractResolver();
                var serializer = JsonSerializer.Create(settings);
                  
               GlobalHost.DependencyResolver.Register(typeof(JsonSerializer),  () => serializer);                
            
                 */

                app.MapSignalR();
            }
        }

        [HubName("MyHub")]
        public class MyHub : Hub
        {
            public void Send(string name, string message)
            {
                Clients.All.addMessage(name, message);
            }
        }
    }
}

Client

(almost the same as Mehrdad Bahrainy reply)

Install-Package Microsoft.AspNet.SignalR.Client -Version 2.2.1

namespace ConsoleApplication116_SignalRClient
{
    class Program
    {
        private static void Main(string[] args)
        {
            var connection = new HubConnection("http://127.0.0.1:8088/");
            var myHub = connection.CreateHubProxy("MyHub");

            Console.WriteLine("Enter your name");    
            string name = Console.ReadLine();

            connection.Start().ContinueWith(task => {
                if (task.IsFaulted)
                {
                    Console.WriteLine("There was an error opening the connection:{0}", task.Exception.GetBaseException());
                }
                else
                {
                    Console.WriteLine("Connected");

                    myHub.On<string, string>("addMessage", (s1, s2) => {
                        Console.WriteLine(s1 + ": " + s2);
                    });

                    while (true)
                    {
                        Console.WriteLine("Please Enter Message");
                        string message = Console.ReadLine();

                        if (string.IsNullOrEmpty(message))
                        {
                            break;
                        }

                        myHub.Invoke<string>("Send", name, message).ContinueWith(task1 => {
                            if (task1.IsFaulted)
                            {
                                Console.WriteLine("There was an error calling send: {0}", task1.Exception.GetBaseException());
                            }
                            else
                            {
                                Console.WriteLine(task1.Result);
                            }
                        });
                    }
                }

            }).Wait();

            Console.Read();
            connection.Stop();
        }
    }
}

Generating combinations in c++

A simple way using std::next_permutation:

#include <iostream>
#include <algorithm>
#include <vector>

int main() {
    int n, r;
    std::cin >> n;
    std::cin >> r;

    std::vector<bool> v(n);
    std::fill(v.end() - r, v.end(), true);

    do {
        for (int i = 0; i < n; ++i) {
            if (v[i]) {
                std::cout << (i + 1) << " ";
            }
        }
        std::cout << "\n";
    } while (std::next_permutation(v.begin(), v.end()));
    return 0;
}

or a slight variation that outputs the results in an easier to follow order:

#include <iostream>
#include <algorithm>
#include <vector>

int main() {
   int n, r;
   std::cin >> n;
   std::cin >> r;

   std::vector<bool> v(n);
   std::fill(v.begin(), v.begin() + r, true);

   do {
       for (int i = 0; i < n; ++i) {
           if (v[i]) {
               std::cout << (i + 1) << " ";
           }
       }
       std::cout << "\n";
   } while (std::prev_permutation(v.begin(), v.end()));
   return 0;
}

A bit of explanation:

It works by creating a "selection array" (v), where we place r selectors, then we create all permutations of these selectors, and print the corresponding set member if it is selected in in the current permutation of v.


You can implement it if you note that for each level r you select a number from 1 to n.

In C++, we need to 'manually' keep the state between calls that produces results (a combination): so, we build a class that on construction initialize the state, and has a member that on each call returns the combination while there are solutions: for instance

#include <iostream>
#include <iterator>
#include <vector>
#include <cstdlib>

using namespace std;

struct combinations
{
    typedef vector<int> combination_t;

    // initialize status
   combinations(int N, int R) :
       completed(N < 1 || R > N),
       generated(0),
       N(N), R(R)
   {
       for (int c = 1; c <= R; ++c)
           curr.push_back(c);
   }

   // true while there are more solutions
   bool completed;

   // count how many generated
   int generated;

   // get current and compute next combination
   combination_t next()
   {
       combination_t ret = curr;

       // find what to increment
       completed = true;
       for (int i = R - 1; i >= 0; --i)
           if (curr[i] < N - R + i + 1)
           {
               int j = curr[i] + 1;
               while (i <= R-1)
                   curr[i++] = j++;
               completed = false;
               ++generated;
               break;
           }

       return ret;
   }

private:

   int N, R;
   combination_t curr;
};

int main(int argc, char **argv)
{
    int N = argc >= 2 ? atoi(argv[1]) : 5;
    int R = argc >= 3 ? atoi(argv[2]) : 2;
    combinations cs(N, R);
    while (!cs.completed)
    {
        combinations::combination_t c = cs.next();
        copy(c.begin(), c.end(), ostream_iterator<int>(cout, ","));
        cout << endl;
    }
    return cs.generated;
}

test output:

1,2,
1,3,
1,4,
1,5,
2,3,
2,4,
2,5,
3,4,
3,5,
4,5,

How do I send a file as an email attachment using Linux command line?

Not a method for sending email, but you can use an online Git server (e.g. Bitbucket or a similar service) for that.

This way, you can use git push commands, and all versions will be stored in a compressed and organized way.