Programs & Examples On #Erlang

Erlang is a general-purpose, garbage-collected programming language and runtime environment, with built-in support for concurrency, distribution and fault tolerance.

Speed comparison with Project Euler: C vs Python vs Erlang vs Haskell

I modified "Jannich Brendle" version to 1000 instead 500. And list the result of euler12.bin, euler12.erl, p12dist.erl. Both erl codes use '+native' to compile.

zhengs-MacBook-Pro:workspace zhengzhibin$ time erl -noshell -s p12dist start
The result is: 842161320.

real    0m3.879s
user    0m14.553s
sys     0m0.314s
zhengs-MacBook-Pro:workspace zhengzhibin$ time erl -noshell -s euler12 solve
842161320

real    0m10.125s
user    0m10.078s
sys     0m0.046s
zhengs-MacBook-Pro:workspace zhengzhibin$ time ./euler12.bin 
842161320

real    0m5.370s
user    0m5.328s
sys     0m0.004s
zhengs-MacBook-Pro:workspace zhengzhibin$

How can I print out all possible letter combinations a given phone number can represent?

Scala solution:

def mnemonics(phoneNum: String, dict: IndexedSeq[String]): Iterable[String] = {
  def mnemonics(d: Int, prefix: String): Seq[String] = {
    if (d >= phoneNum.length) {
      Seq(prefix)
    } else {
      for {
        ch <- dict(phoneNum.charAt(d).asDigit)
        num <- mnemonics(d + 1, s"$prefix$ch")
      } yield num
    }
  }

  mnemonics(0, "")
}

Assuming each digit maps to at most 4 characters, the number of recursive calls T satisfy the inequality T(n) <= 4T(n-1), which is of the order 4^n.

What is JAVA_HOME? How does the JVM find the javac path stored in JAVA_HOME?

JAVA_HOME is a environment variable (in Unix terminologies), or a PATH variable (in Windows terminology). A lot of well behaving Java applications (which need the JDK/JRE) to run, looks up the JAVA_HOME variable for the location where the Java compiler/interpreter may be found.

Excel Reference To Current Cell

Full credit to the top answer by @rick-teachey, but you can extend that approach to work with Conditional Formatting. So that this answer is complete, I will duplicate Rick's answer in summary form and then extend it:

  1. Select cell A1 in any worksheet.
  2. Create a Named Range called THIS and set the Refers to: to =!A1.

Attempting to use THIS in Conditional Formatting formulas will result in the error:

You may not use references to other workbooks for Conditional Formatting criteria

If you want THIS to work in Conditional Formatting formulas:

  1. Create another Named Range called THIS_CF and set the Refers to: to =THIS.

You can now use THIS_CF to refer to the current cell in Conditional Formatting formulas.

You can also use this approach to create other relative Named Ranges, such as THIS_COLUMN, THIS_ROW, ROW_ABOVE, COLUMN_LEFT, etc.

Can't ignore UserInterfaceState.xcuserstate

For xcode 8.3.3 I just checked tried the above code and observe that, now in this casewe have to change the commands to like this

first you can create a .gitignore file by using

 touch .gitignore

after that you can delete all the userInterface file by using this command and by using this command it will respect your .gitignore file.

 git rm --cached [project].xcworkspace/xcuserdata/[username].xcuserdatad/UserInterfaceState.xcuserstate
 git commit -m "Removed file that shouldn't be tracked"

Delete files older than 15 days using PowerShell

Basically, you iterate over files under the given path, subtract the CreationTime of each file found from the current time, and compare against the Days property of the result. The -WhatIf switch will tell you what will happen without actually deleting the files (which files will be deleted), remove the switch to actually delete the files:

$old = 15
$now = Get-Date

Get-ChildItem $path -Recurse |
Where-Object {-not $_.PSIsContainer -and $now.Subtract($_.CreationTime).Days -gt $old } |
Remove-Item -WhatIf

Using onBlur with JSX and React

There are a few problems here.

1: onBlur expects a callback, and you are calling renderPasswordConfirmError and using the return value, which is null.

2: you need a place to render the error.

3: you need a flag to track "and I validating", which you would set to true on blur. You can set this to false on focus if you want, depending on your desired behavior.

handleBlur: function () {
  this.setState({validating: true});
},
render: function () {
  return <div>
    ...
    <input
        type="password"
        placeholder="Password (confirm)"
        valueLink={this.linkState('password2')}
        onBlur={this.handleBlur}
     />
    ...
    {this.renderPasswordConfirmError()}
  </div>
},
renderPasswordConfirmError: function() {
  if (this.state.validating && this.state.password !== this.state.password2) {
    return (
      <div>
        <label className="error">Please enter the same password again.</label>
      </div>
    );
  }  
  return null;
},

How to increment datetime by custom months in python without using library

Simplest solution is to go at the end of the month (we always know that months have at least 28 days) and add enough days to move to the next moth:

>>> from datetime import datetime, timedelta
>>> today = datetime.today()
>>> today
datetime.datetime(2014, 4, 30, 11, 47, 27, 811253)
>>> (today.replace(day=28) + timedelta(days=10)).replace(day=today.day)
datetime.datetime(2014, 5, 30, 11, 47, 27, 811253)

Also works between years:

>>> dec31
datetime.datetime(2015, 12, 31, 11, 47, 27, 811253)
>>> today = dec31
>>> (today.replace(day=28) + timedelta(days=10)).replace(day=today.day)
datetime.datetime(2016, 1, 31, 11, 47, 27, 811253)

Just keep in mind that it is not guaranteed that the next month will have the same day, for example when moving from 31 Jan to 31 Feb it will fail:

>>> today
datetime.datetime(2016, 1, 31, 11, 47, 27, 811253)
>>> (today.replace(day=28) + timedelta(days=10)).replace(day=today.day)
Traceback (most recent call last):
  File "<stdin>", line 1, in <module>
ValueError: day is out of range for month

So this is a valid solution if you need to move to the first day of the next month, as you always know that the next month has day 1 (.replace(day=1)). Otherwise, to move to the last available day, you might want to use:

>>> today
datetime.datetime(2016, 1, 31, 11, 47, 27, 811253)
>>> next_month = (today.replace(day=28) + timedelta(days=10))
>>> import calendar
>>> next_month.replace(day=min(today.day, 
                               calendar.monthrange(next_month.year, next_month.month)[1]))
datetime.datetime(2016, 2, 29, 11, 47, 27, 811253)

open resource with relative path in Java

@GianCarlo: You can try calling System property user.dir that will give you root of your java project and then do append this path to your relative path for example:

String root = System.getProperty("user.dir");
String filepath = "/path/to/yourfile.txt"; // in case of Windows: "\\path \\to\\yourfile.txt
String abspath = root+filepath;



// using above path read your file into byte []
File file = new File(abspath);
FileInputStream fis = new FileInputStream(file);
byte []filebytes = new byte[(int)file.length()];
fis.read(filebytes);

How do I test axios in Jest?

For those looking to use axios-mock-adapter in place of the mockfetch example in the Redux documentation for async testing, I successfully used the following:

File actions.test.js:

describe('SignInUser', () => {
  var history = {
    push: function(str) {
        expect(str).toEqual('/feed');
    }
  }

  it('Dispatches authorization', () => {
    let mock = new MockAdapter(axios);
    mock.onPost(`${ROOT_URL}/auth/signin`, {
        email: '[email protected]',
        password: 'test'
    }).reply(200, {token: 'testToken' });

    const expectedActions = [ { type: types.AUTH_USER } ];
    const store = mockStore({ auth: [] });

    return store.dispatch(actions.signInUser({
        email: '[email protected]',
        password: 'test',
      }, history)).then(() => {
        expect(store.getActions()).toEqual(expectedActions);
  });

});

In order to test a successful case for signInUser in file actions/index.js:

export const signInUser = ({ email, password }, history) => async dispatch => {
  const res = await axios.post(`${ROOT_URL}/auth/signin`, { email, password })
    .catch(({ response: { data } }) => {
        ...
  });

  if (res) {
    dispatch({ type: AUTH_USER });                 // Test verified this
    localStorage.setItem('token', res.data.token); // Test mocked this
    history.push('/feed');                         // Test mocked this
  }
}

Given that this is being done with jest, the localstorage call had to be mocked. This was in file src/setupTests.js:

const localStorageMock = {
  removeItem: jest.fn(),
  getItem: jest.fn(),
  setItem: jest.fn(),
  clear: jest.fn()
};
global.localStorage = localStorageMock;

PostgreSQL CASE ... END with multiple conditions

This kind of code perhaps should work for You

SELECT
 *,
 CASE
  WHEN (pvc IS NULL OR pvc = '') AND (datepose < 1980) THEN '01'
  WHEN (pvc IS NULL OR pvc = '') AND (datepose >= 1980) THEN '02'
  WHEN (pvc IS NULL OR pvc = '') AND (datepose IS NULL OR datepose = 0) THEN '03'
  ELSE '00'
 END AS modifiedpvc
FROM my_table;


 gid | datepose | pvc | modifiedpvc 
-----+----------+-----+-------------
   1 |     1961 | 01  | 00
   2 |     1949 |     | 01
   3 |     1990 | 02  | 00
   1 |     1981 |     | 02
   1 |          | 03  | 00
   1 |          |     | 03
(6 rows)

Nested Git repositories?

You could add

/project_root/third_party_git_repository_used_by_my_project

to

/project_root/.gitignore

that should prevent the nested repo to be included in the parent repo, and you can work with them independently.

But: If a user runs git clean -dfx in the parent repo, it will remove the ignored nested repo. Another way is to symlink the folder and ignore the symlink. If you then run git clean, the symlink is removed, but the 'nested' repo will remain intact as it really resides elsewhere.

Error when checking model input: expected convolution2d_input_1 to have 4 dimensions, but got array with shape (32, 32, 3)

You should simply apply the following transformation to your input data array.

input_data = input_data.reshape((-1, image_side1, image_side2, channels))

Regex to match words of a certain length

Method 1

Word boundaries would work perfectly here, such as with:

\b\w{3,8}\b
\b\w{2,}
\b\w{,10}\b
\b\w{5}\b

RegEx Demo 1

Java

Some languages such as Java and C++ are double-escape required:

\\b\\w{3,8}\\b
\\b\\w{2,}
\\b\\w{,10}\\b
\\b\\w{5}\\b

PS: \\b\\w{,10}\\b may not work for all languages or flavors.

Test 1

import java.util.regex.Matcher;
import java.util.regex.Pattern;


public class RegularExpression{

    public static void main(String[] args){


        final String regex = "\\b\\w{3,8}\\b";
        final String string = "words with length three to eight";

        final Pattern pattern = Pattern.compile(regex, Pattern.MULTILINE);
        final Matcher matcher = pattern.matcher(string);

        while (matcher.find()) {
            System.out.println("Full match: " + matcher.group(0));
        }

    }
}

Output 1

Full match: words
Full match: with
Full match: length
Full match: three
Full match: eight

Method 2

Another good-to-know method is to use negative lookarounds:

(?<!\w)\w{3,8}(?!\w)
(?<!\w)\w{2,}
(?<!\w)\w{,10}(?!\w)
(?<!\w)\w{5}(?!\w)

Java

(?<!\\w)\\w{3,8}(?!\\w)
(?<!\\w)\\w{2,}
(?<!\\w)\\w{,10}(?!\\w)
(?<!\\w)\\w{5}(?!\\w)

RegEx Demo 2

Test 2

import java.util.regex.Matcher;
import java.util.regex.Pattern;


public class RegularExpression{

    public static void main(String[] args){


        final String regex = "(?<!\\w)\\w{1,10}(?!\\w)";
        final String string = "words with length three to eight";

        final Pattern pattern = Pattern.compile(regex, Pattern.MULTILINE);
        final Matcher matcher = pattern.matcher(string);

        while (matcher.find()) {
            System.out.println("Full match: " + matcher.group(0));
        }

    }
}

Output 2

Full match: words
Full match: with
Full match: length
Full match: three
Full match: to
Full match: eight

RegEx Circuit

jex.im visualizes regular expressions:

enter image description here


If you wish to simplify/modify/explore the expression, it's been explained on the top right panel of regex101.com. If you'd like, you can also watch in this link, how it would match against some sample inputs.


Is there a good JSP editor for Eclipse?

You could check out JBoss Tools plugin.

Apply CSS Style to child elements

div.test td, div.test caption, div.test th 

works for me.

The child selector > does not work in IE6.

Close all infowindows in Google Maps API v3

Declare global variables:

var mapOptions;
var map;
var infowindow;
var marker;
var contentString;
var image;

In intialize use the map's addEvent method:

google.maps.event.addListener(map, 'click', function() {
    if (infowindow) {
        infowindow.close();
    }
});

How do I find the value of $CATALINA_HOME?

Tomcat can tell you in several ways. Here's the easiest:

 $ /path/to/catalina.sh version
Using CATALINA_BASE:   /usr/local/apache-tomcat-7.0.29
Using CATALINA_HOME:   /usr/local/apache-tomcat-7.0.29
Using CATALINA_TMPDIR: /usr/local/apache-tomcat-7.0.29/temp
Using JRE_HOME:        /System/Library/Frameworks/JavaVM.framework/Versions/CurrentJDK/Home
Using CLASSPATH:       /usr/local/apache-tomcat-7.0.29/bin/bootstrap.jar:/usr/local/apache-tomcat-7.0.29/bin/tomcat-juli.jar
Server version: Apache Tomcat/7.0.29
Server built:   Jul 3 2012 11:31:52
Server number:  7.0.29.0
OS Name:        Mac OS X
OS Version:     10.7.4
Architecture:   x86_64
JVM Version:    1.6.0_33-b03-424-11M3720
JVM Vendor:     Apple Inc.

If you don't know where catalina.sh is (or it never gets called), you can usually find it via ps:

$ ps aux | grep catalina
chris            930   0.0  3.1  2987336 258328 s000  S    Wed01PM   2:29.43 /System/Library/Java/JavaVirtualMachines/1.6.0.jdk/Contents/Home/bin/java -Dnop -Djava.util.logging.manager=org.apache.juli.ClassLoaderLogManager -Djava.library.path=/usr/local/apache-tomcat-7.0.29/lib -Djava.endorsed.dirs=/usr/local/apache-tomcat-7.0.29/endorsed -classpath /usr/local/apache-tomcat-7.0.29/bin/bootstrap.jar:/usr/local/apache-tomcat-7.0.29/bin/tomcat-juli.jar -Dcatalina.base=/Users/chris/blah/blah -Dcatalina.home=/usr/local/apache-tomcat-7.0.29 -Djava.io.tmpdir=/Users/chris/blah/blah/temp org.apache.catalina.startup.Bootstrap start

From the ps output, you can see both catalina.home and catalina.base. catalina.home is where the Tomcat base files are installed, and catalina.base is where the running configuration of Tomcat exists. These are often set to the same value unless you have configured your Tomcat for multiple (configuration) instances to be launched from a single Tomcat base install.

You can also interrogate the JVM directly if you can't find it in a ps listing:

$ jinfo -sysprops 930 | grep catalina
Attaching to process ID 930, please wait...
Debugger attached successfully.
Server compiler detected.
JVM version is 20.8-b03-424
catalina.base = /Users/chris/blah/blah
[...]
catalina.home = /usr/local/apache-tomcat-7.0.29

If you can't manage that, you can always try to write a JSP that dumps the values of the two system properties catalina.home and catalina.base.

How to get Real IP from Visitor?

This is my function.

benefits :

  • Work if $_SERVER was not available.
  • Filter private and/or reserved IPs;
  • Process all forwarded IPs in X_FORWARDED_FOR
  • Compatible with CloudFlare
  • Can set a default if no valid IP found!
  • Short & Simple !

/**
 * Get real user ip
 *
 * Usage sample:
 * GetRealUserIp();
 * GetRealUserIp('ERROR',FILTER_FLAG_NO_RES_RANGE);
 * 
 * @param string $default default return value if no valid ip found
 * @param int    $filter_options filter options. default is FILTER_FLAG_NO_PRIV_RANGE | FILTER_FLAG_NO_RES_RANGE
 *
 * @return string real user ip
 */

function GetRealUserIp($default = NULL, $filter_options = 12582912) {
    $HTTP_X_FORWARDED_FOR = isset($_SERVER)? $_SERVER["HTTP_X_FORWARDED_FOR"]:getenv('HTTP_X_FORWARDED_FOR');
    $HTTP_CLIENT_IP = isset($_SERVER)?$_SERVER["HTTP_CLIENT_IP"]:getenv('HTTP_CLIENT_IP');
    $HTTP_CF_CONNECTING_IP = isset($_SERVER)?$_SERVER["HTTP_CF_CONNECTING_IP"]:getenv('HTTP_CF_CONNECTING_IP');
    $REMOTE_ADDR = isset($_SERVER)?$_SERVER["REMOTE_ADDR"]:getenv('REMOTE_ADDR');

    $all_ips = explode(",", "$HTTP_X_FORWARDED_FOR,$HTTP_CLIENT_IP,$HTTP_CF_CONNECTING_IP,$REMOTE_ADDR");
    foreach ($all_ips as $ip) {
        if ($ip = filter_var($ip, FILTER_VALIDATE_IP, $filter_options))
            break;
    }
    return $ip?$ip:$default;
}

Can I add background color only for padding?

I'd just wrap the header with another div and play with borders.

<div class="header-border"><div class="header-real">

    <p>Foo</p>

</div></div>

CSS:

.header-border { border: 2px solid #000000; }
.header-real { border: 10px solid #003399; background: #cccccc; padding: 10px; }

Bootstrap 3, 4 and 5 .container-fluid with grid adding unwanted padding

In the new alpha versions they've introduced utility spacing classes. The structure can then be tweaked if you use them in a clever way.

Spacing utility classes

<div class="container-fluid">
    <div class="row">
        <div class="col-sm-4 col-md-3 pl-0">…</div>
        <div class="col-sm-4 col-md-3">…</div>
        <div class="col-sm-4 col-md-3">…</div>
        <div class="col-sm-4 col-md-3 pr-0">…</div>
    </div>
</div>

pl-0 and pr-0 will remove leading and trailing padding from the columns. One issue left is the embedded rows of a column, as they still have negative margin. In this case:

<div class="col-sm-12 col-md-6 pl-0">
    <div class="row ml-0">
</div>

Version differences

Also note the utility spacing classes were changed since version 4.0.0-alpha.4. Before they were separated by 2 dashes e.g. => p-x-0 and p-l-0 and so on ...

To stay on topic for the version 3: This is what I use on Bootstrap 3 projects and include the compass setup, for this particular spacing utility, into bootstrap-sass (version 3) or bootstrap (version 4.0.0-alpha.3) with double dashes or bootstrap (version 4.0.0-alpha.4 and up) with single dashes.

Also, latest version(s) go up 'till 5 times a ratio (ex: pt-5 padding-top 5) instead of only 3.


Compass

$grid-breakpoints: (xs: 0, sm: 576px, md: 768px, lg: 992px, xl: 1200px) !default;

@import "../scss/mixins/breakpoints"; // media-breakpoint-up, breakpoint-infix
@import "../scss/utilities/_spacing.scss";

CSS output

You can ofcourse always copy/paste the padding spacing classes only from a generated css file.

.p-0 { padding: 0 !important; }
.pt-0 { padding-top: 0 !important; }
.pr-0 { padding-right: 0 !important; }
.pb-0 { padding-bottom: 0 !important; }
.pl-0 { padding-left: 0 !important; }
.px-0 { padding-right: 0 !important; padding-left: 0 !important; }
.py-0 { padding-top: 0 !important; padding-bottom: 0 !important; }
.p-1 { padding: 0.25rem !important; }
.pt-1 { padding-top: 0.25rem !important; }
.pr-1 { padding-right: 0.25rem !important; }
.pb-1 { padding-bottom: 0.25rem !important; }
.pl-1 { padding-left: 0.25rem !important; }
.px-1 { padding-right: 0.25rem !important; padding-left: 0.25rem !important; }
.py-1 { padding-top: 0.25rem !important; padding-bottom: 0.25rem !important; }
.p-2 { padding: 0.5rem !important; }
.pt-2 { padding-top: 0.5rem !important; }
.pr-2 { padding-right: 0.5rem !important; }
.pb-2 { padding-bottom: 0.5rem !important; }
.pl-2 { padding-left: 0.5rem !important; }
.px-2 { padding-right: 0.5rem !important; padding-left: 0.5rem !important; }
.py-2 { padding-top: 0.5rem !important; padding-bottom: 0.5rem !important; }
.p-3 { padding: 1rem !important; }
.pt-3 { padding-top: 1rem !important; }
.pr-3 { padding-right: 1rem !important; }
.pb-3 { padding-bottom: 1rem !important; }
.pl-3 { padding-left: 1rem !important; }
.px-3 { padding-right: 1rem !important; padding-left: 1rem !important; }
.py-3 { padding-top: 1rem !important; padding-bottom: 1rem !important; }
.p-4 { padding: 1.5rem !important; }
.pt-4 { padding-top: 1.5rem !important; }
.pr-4 { padding-right: 1.5rem !important; }
.pb-4 { padding-bottom: 1.5rem !important; }
.pl-4 { padding-left: 1.5rem !important; }
.px-4 { padding-right: 1.5rem !important; padding-left: 1.5rem !important; }
.py-4 { padding-top: 1.5rem !important; padding-bottom: 1.5rem !important; }
.p-5 { padding: 3rem !important; }
.pt-5 { padding-top: 3rem !important; }
.pr-5 { padding-right: 3rem !important; }
.pb-5 { padding-bottom: 3rem !important; }
.pl-5 { padding-left: 3rem !important; }
.px-5 { padding-right: 3rem !important; padding-left: 3rem !important; }
.py-5 { padding-top: 3rem !important; padding-bottom: 3rem !important; }

ModalPopupExtender OK Button click event not firing?

I was just searching for a solution for this :)

it appears that you can't have OkControlID assign to a control if you want to that control fires an event, just removing this property I got everything working again.

my code (working):

<asp:Panel ID="pnlResetPanelsView" CssClass="modalPopup" runat="server" Style="display:none;">
    <h2>
        Warning</h2>
    <p>
        Do you really want to reset the panels to the default view?</p>
    <div style="text-align: center;">
        <asp:Button ID="btnResetPanelsViewOK" Width="60" runat="server" Text="Yes" 
            CssClass="buttonSuperOfficeLayout" OnClick="btnResetPanelsViewOK_Click" />&nbsp;
        <asp:Button ID="btnResetPanelsViewCancel" Width="60" runat="server" Text="No" CssClass="buttonSuperOfficeLayout" />
    </div>
</asp:Panel>
<ajax:ModalPopupExtender ID="mpeResetPanelsView" runat="server" TargetControlID="btnResetView"
    PopupControlID="pnlResetPanelsView" BackgroundCssClass="modalBackground" DropShadow="true"
    CancelControlID="btnResetPanelsViewCancel" />

Java foreach loop: for (Integer i : list) { ... }

The API does not support that directly. You can use the for(int i..) loop and count the elements or use subLists(0, size - 1) and handle the last element explicitly:

  if(x.isEmpty()) return;
  int last = x.size() - 1;
  for(Integer i : x.subList(0, last)) out.println(i);
  out.println("last " + x.get(last));

This is only useful if it does not introduce redundancy. It performs better than the counting version (after the subList overhead is amortized). (Just in case you cared after the boxing anyway).

@Autowired - No qualifying bean of type found for dependency at least 1 bean

@Service: It tells that particular class is a Service to the client. Service class contains mainly business Logic. If you have more Service classes in a package than provide @Qualifier otherwise it should not require @Qualifier.

Case 1:

@Service("employeeService")
public class EmployeeServiceImpl implements EmployeeService{
}

Case2:

@Service
public class EmployeeServiceImpl implements EmployeeService{
}

both cases are working...

How to get option text value using AngularJS?

The best way is to use the ng-options directive on the select element.

Controller

function Ctrl($scope) {
  // sort options
  $scope.products = [{
    value: 'prod_1',
    label: 'Product 1'
  }, {
    value: 'prod_2',
    label: 'Product 2'
  }];   
}

HTML

<select ng-model="selected_product" 
        ng-options="product as product.label for product in products">           
</select>

This will bind the selected product object to the ng-model property - selected_product. After that you can use this:

<p>Ordered by: {{selected_product.label}}</p>

jsFiddle: http://jsfiddle.net/bmleite/2qfSB/

How to create an AVD for Android 4.0

This answer is for creating AVD in Android Studio.

  1. First click on AVD button on your Android Studio top bar.

image 1

  1. In this window click on Create Virtual Device

image 2

  1. Now you will choose hardware profile for AVD and click Next.

image 3

  1. Choose Android Api Version you want in your AVD. Download if no api exist. Click next.

image 4

  1. This is now window for customizing some AVD feature like camera, network, memory and ram size etc. Just keep default and click Finish.

image 5

  1. You AVD is ready, now click on AVD button in Android Studio (same like 1st step). Then you will able to see created AVD in list. Click on Play button on your AVD.

image 6

  1. Your AVD will start soon.

image 7

urllib and "SSL: CERTIFICATE_VERIFY_FAILED" Error

The SSL: CERTIFICATE_VERIFY_FAILED error could also occur because an Intermediate Certificate is missing in the ca-certificates package on Linux. For example, in my case the intermediate certificate "DigiCert SHA2 Secure Server CA" was missing in the ca-certificates package even though the Firefox browser includes it. You can find out which certificate is missing by directly running the wget command on the URL causing this error. Then you can search for the corresponding link to the CRT file for this certificate from the official website (e.g. https://www.digicert.com/digicert-root-certificates.htm in my case) of the Certificate Authority. Now, to include the certificate that is missing in your case, you may run the below commands using your CRT file download link instead:

wget https://cacerts.digicert.com/DigiCertSHA2SecureServerCA.crt

mv DigiCertSHA2SecureServerCA.crt DigiCertSHA2SecureServerCA.der

openssl x509 -inform DER -outform PEM -in DigiCertSHA2SecureServerCA.der -out DigicertSHA2SecureServerCA.pem.crt

sudo mkdir /usr/share/ca-certificates/extra

sudo cp DigicertSHA2SecureServerCA.pem.crt /usr/share/ca-certificates/extra/

sudo dpkg-reconfigure ca-certificates

After this you may test again with wget for your URL as well as by using the python urllib package. For more details, refer to: https://bugs.launchpad.net/ubuntu/+source/ca-certificates/+bug/1795242

Laravel Eloquent - distinct() and count() not working properly together

Based on Laravel docs for raw queries I was able to get count for a select field to work with this code in the product model.

public function scopeShowProductCount($query)
{
    $query->select(DB::raw('DISTINCT pid, COUNT(*) AS count_pid'))
          ->groupBy('pid')
          ->orderBy('count_pid', 'desc');
}

This facade worked to get the same result in the controller:

$products = DB::table('products')->select(DB::raw('DISTINCT pid, COUNT(*) AS count_pid'))->groupBy('pid')->orderBy('count_pid', 'desc')->get();

The resulting dump for both queries was as follows:

#attributes: array:2 [
  "pid" => "1271"
  "count_pid" => 19
],
#attributes: array:2 [
  "pid" => "1273"
  "count_pid" => 12
],
#attributes: array:2 [
  "pid" => "1275"
  "count_pid" => 7
]

How to convert minutes to hours/minutes and add various time values together using jQuery?

Very short code for transferring minutes in two formats!

_x000D_
_x000D_
let format1 = (n) => `${n / 60 ^ 0}:` + n % 60_x000D_
_x000D_
console.log(format1(135)) // "2:15"_x000D_
console.log(format1(55)) // "0:55"_x000D_
_x000D_
let format2 = (n) => `0${n / 60 ^ 0}`.slice(-2) + ':' + ('0' + n % 60).slice(-2)_x000D_
_x000D_
console.log(format2(135)) // "02:15"_x000D_
console.log(format2(5)) // "00:05"
_x000D_
_x000D_
_x000D_

Extending an Object in Javascript

Mozilla 'announces' object extending from ECMAScript 6.0:

https://developer.mozilla.org/en-US/docs/Web/JavaScript/Reference/Classes/extends

NOTE: This is an experimental technology, part of the ECMAScript 6 (Harmony) proposal.

class Square extends Polygon {
  constructor(length) {
    // Here, it calls the parent class' constructor with lengths
    // provided for the Polygon's width and height
    super(length, length);
    // Note: In derived classes, super() must be called before you
    // can use 'this'. Leaving this out will cause a reference error.
    this.name = 'Square';
  }

  get area() {
    return this.height * this.width;
  }

  set area(value) {
    this.area = value;     } 
}

This technology is available in Gecko (Google Chrome / Firefox) - 03/2015 nightly builds.

CSS :: child set to change color on parent hover, but changes also when hovered itself

If you don't care about supporting old browsers, you can use :not() to exclude that element:

.parent:hover span:not(:hover) {
    border: 10px solid red;
}

Demo: http://jsfiddle.net/vz9A9/1/

If you do want to support them, the I guess you'll have to either use JavaScript or override the CSS properties again:

.parent span:hover {
    border: 10px solid green;
}

Font scaling based on width of container

This may not be super practical, but if you want a font to be a direct function of the parent, without having any JavaScript that listens/loops (interval) to read the size of the div/page, there is a way to do it. Iframes.

Anything within the iframe will consider the size of the iframe as the size of the viewport. So the trick is to just make an iframe whose width is the maximum width you want your text to be, and whose height is equal to the maximum height * the particular text's aspect ratio.

Setting aside the limitation that viewport units can't also come along side parent units for text (as in, having the % size behave like everyone else), viewport units do provide a very powerful tool: being able to get the minimum/maximum dimension. You can't do that anywhere else - you can't say...make the height of this div be the width of the parent * something.

That being said, the trick is to use vmin, and to set the iframe size so that [fraction] * total height is a good font size when the height is the limiting dimension, and [fraction] * total width when the width is the limiting dimension. This is why the height has to be a product of the width and the aspect ratio.

For my particular example, you have

.main iframe{
  position: absolute;
  top: 50%;
  left: 50%;
  width: 100%;
  height: calc(3.5 * 100%);
  background: rgba(0, 0, 0, 0);
  border-style: none;
  transform: translate3d(-50%, -50%, 0);
}

The small annoyance with this method is that you have to manually set the CSS of the iframe. If you attach the whole CSS file, that would take up a lot of bandwidth for many text areas. So, what I do is attach the rule that I want directly from my CSS.

var rule = document.styleSheets[1].rules[4];
var iDoc = document.querySelector('iframe').contentDocument;
iDoc.styleSheets[0].insertRule(rule.cssText);

You can write small function that gets the CSS rule / all CSS rules that would affect the text area.

I cannot think of another way to do it without having some cycling/listening JavaScript. The real solution would be for browsers to provide a way to scale text as a function of the parent container and to also provide the same vmin/vmax type functionality.

JSFiddle: https://jsfiddle.net/0jr7rrgm/3/ (click once to lock the red square to the mouse, and click again to release)

Most of the JavaScript in the fiddle is just my custom click-drag function.

Center Triangle at Bottom of Div

You could also use a CSS "calc" to get the same effect instead of using the negative margin or transform properties (in case you want to use those properties for anything else).

.hero:after,
.hero:after {
    z-index: -1;
    position: absolute;
    top: 98.1%;
    left: calc(50% - 25px);
    content: '';
    width: 0;
    height: 0;
    border-top: solid 50px #e15915;
    border-left: solid 50px transparent;
    border-right: solid 50px transparent;
}

Spring mvc @PathVariable

have a look at the below code snippet.

@RequestMapping(value = "edit.htm", method = RequestMethod.GET) 
    public ModelAndView edit(@RequestParam("id") String id) throws Exception {
        ModelMap modelMap = new ModelMap();
        modelMap.addAttribute("user", userinfoDao.findById(id));
        return new ModelAndView("edit", modelMap);      
    }

If you want the complete project to see how it works then download it from below link:-

UserInfo Project on GitLab

Javascript dynamic array of strings

As far as I know, Javascript has dynamic arrays. You can add,delete and modify the elements on the fly.

var myArray = [1,2,3,4,5,6,7,8,9,10];
myArray.push(11);
document.writeln(myArray);  // Gives 1,2,3,4,5,6,7,8,9,10,11


var myArray = [1,2,3,4,5,6,7,8,9,10];
var popped = myArray.pop();
document.writeln(myArray);  // Gives 1,2,3,4,5,6,7,8,9

You can even add elements like

var myArray = new Array()
myArray[0] = 10
myArray[1] = 20
myArray[2] = 30

you can even change the values

myArray[2] = 40

Printing Order

If you want in the same order, this would suffice. Javascript prints the values in the order of key values. If you have inserted values in the array in monotonically increasing key values, then they will be printed in the same way unless you want to change the order.

Page Submission

If you are using JavaScript you don't even need to submit the values to the different page. You can even show the data on the same page by manipulating the DOM.

How to clone ArrayList and also clone its contents?

The package import org.apache.commons.lang.SerializationUtils;

There is a method SerializationUtils.clone(Object);

Example

this.myObjectCloned = SerializationUtils.clone(this.object);

C# elegant way to check if a property's property is null

You could do this:

class ObjectAType
{
    public int PropertyC
    {
        get
        {
            if (PropertyA == null)
                return 0;
            if (PropertyA.PropertyB == null)
                return 0;
            return PropertyA.PropertyB.PropertyC;
        }
    }
}



if (ObjectA != null)
{
    int value = ObjectA.PropertyC;
    ...
}

Or even better might be this:

private static int GetPropertyC(ObjectAType objectA)
{
    if (objectA == null)
        return 0;
    if (objectA.PropertyA == null)
        return 0;
    if (objectA.PropertyA.PropertyB == null)
        return 0;
    return objectA.PropertyA.PropertyB.PropertyC;
}


int value = GetPropertyC(ObjectA);

Apply jQuery datepicker to multiple instances

I had a similar problem with dynamically adding datepicker classes. The solution I found was to comment out line 46 of datepicker.js

// this.element.on('click', $.proxy(this.show, this));

Efficient way to add spaces between characters in a string

A very pythonic and practical way to do it is by using the string join() method:

str.join(iterable)

The official Python documentations says:

Return a string which is the concatenation of the strings in iterable... The separator between elements is the string providing this method.

How to use it?

Remember: this is a string method.

This method will be applied to the str above, which reflects the string that will be used as separator of the items in the iterable.

Let's have some practical example!

iterable = "BINGO"
separator = " " # A whitespace character.
                # The string to which the method will be applied
separator.join(iterable)
> 'B I N G O'

In practice you would do it like this:

iterable = "BINGO"    
" ".join(iterable)
> 'B I N G O'

But remember that the argument is an iterable, like a string, list, tuple. Although the method returns a string.

iterable = ['B', 'I', 'N', 'G', 'O']    
" ".join(iterable)
> 'B I N G O'

What happens if you use a hyphen as a string instead?

iterable = ['B', 'I', 'N', 'G', 'O']    
"-".join(iterable)
> 'B-I-N-G-O'

How to print the full NumPy array, without truncation?

Use numpy.set_printoptions:

import sys
import numpy
numpy.set_printoptions(threshold=sys.maxsize)

Getting values from query string in an url using AngularJS $location

In my NodeJS example, I have an url "localhost:8080/Lists/list1.html?x1=y" that I want to traverse and acquire values.

In order to work with $location.search() to get x1=y, I have done a few things

  1. script source to angular-route.js
  2. Inject 'ngRoute' into your app module's dependencies
  3. Config your locationProvider
  4. Add the base tag for $location (if you don't, your search().x1 would return nothing or undefined. Or if the base tag has the wrong info, your browser would not be able to find your files inside script src that your .html needs. Always open page's view source to test your file locations!)
  5. invoke the location service (search())

my list1.js has

    var app = angular.module('NGApp', ['ngRoute']);  //dependencies : ngRoute
    app.config(function ($locationProvider) { //config your locationProvider
         $locationProvider.html5Mode(true).hashPrefix('');
    });

    app.controller('NGCtrl', function ($scope, datasvc, $location) {// inject your location service
        //var val = window.location.href.toString().split('=')[1];
        var val = $location.search().x1;    alert(val);
        $scope.xout = function () {
           datasvc.out(val)
           .then(function (data) {
              $scope.x1 = val;
              $scope.allMyStuffs = data.all;
           });
        };
        $scope.xout();
    });

and my list1.html has

<head>
    <base href=".">
    </head>
<body ng-controller="NGCtrl">
<div>A<input ng-model="x1"/><br/><textarea ng-model="allMyStuffs"/></div>
<script src="../js/jquery-2.1.4.min.js"></script>
<script src="../js/jquery-ui.min.js"></script>
<script src="https://ajax.googleapis.com/ajax/libs/angularjs/1.4.9/angular.min.js"></script>
<script src="https://ajax.googleapis.com/ajax/libs/angularjs/1.4.9/angular-route.js"></script>
<script src="../js/bootstrap.min.js"></script>
<script src="../js/ui-bootstrap-tpls-0.14.3.min.js"></script>
<script src="list1.js"></script>
</body>

Guide: https://code.angularjs.org/1.2.23/docs/guide/$location

Storing C++ template function definitions in a .CPP file

Let's take one example, let's say for some reason you want to have a template class:

//test_template.h:
#pragma once
#include <cstdio>

template <class T>
class DemoT
{
public:
    void test()
    {
        printf("ok\n");
    }
};

template <>
void DemoT<int>::test()
{
    printf("int test (int)\n");
}


template <>
void DemoT<bool>::test()
{
    printf("int test (bool)\n");
}

If you compile this code with Visual Studio - it works out of box. gcc will produce linker error (if same header file is used from multiple .cpp files):

error : multiple definition of `DemoT<int>::test()'; your.o: .../test_template.h:16: first defined here

It's possible to move implementation to .cpp file, but then you need to declare class like this -

//test_template.h:
#pragma once
#include <cstdio>

template <class T>
class DemoT
{
public:
    void test()
    {
        printf("ok\n");
    }
};

template <>
void DemoT<int>::test();

template <>
void DemoT<bool>::test();

// Instantiate parametrized template classes, implementation resides on .cpp side.
template class DemoT<bool>;
template class DemoT<int>;

And then .cpp will look like this:

//test_template.cpp:
#include "test_template.h"

template <>
void DemoT<int>::test()
{
    printf("int test (int)\n");
}


template <>
void DemoT<bool>::test()
{
    printf("int test (bool)\n");
}

Without two last lines in header file - gcc will work fine, but Visual studio will produce an error:

 error LNK2019: unresolved external symbol "public: void __cdecl DemoT<int>::test(void)" (?test@?$DemoT@H@@QEAAXXZ) referenced in function

template class syntax is optional in case if you want to expose function via .dll export, but this is applicable only for windows platform - so test_template.h could look like this:

//test_template.h:
#pragma once
#include <cstdio>

template <class T>
class DemoT
{
public:
    void test()
    {
        printf("ok\n");
    }
};

#ifdef _WIN32
    #define DLL_EXPORT __declspec(dllexport) 
#else
    #define DLL_EXPORT
#endif

template <>
void DLL_EXPORT DemoT<int>::test();

template <>
void DLL_EXPORT DemoT<bool>::test();

with .cpp file from previous example.

This however gives more headache to linker, so it's recommended to use previous example if you don't export .dll function.

Creating Scheduled Tasks

You can use Task Scheduler Managed Wrapper:

using System;
using Microsoft.Win32.TaskScheduler;

class Program
{
   static void Main(string[] args)
   {
      // Get the service on the local machine
      using (TaskService ts = new TaskService())
      {
         // Create a new task definition and assign properties
         TaskDefinition td = ts.NewTask();
         td.RegistrationInfo.Description = "Does something";

         // Create a trigger that will fire the task at this time every other day
         td.Triggers.Add(new DailyTrigger { DaysInterval = 2 });

         // Create an action that will launch Notepad whenever the trigger fires
         td.Actions.Add(new ExecAction("notepad.exe", "c:\\test.log", null));

         // Register the task in the root folder
         ts.RootFolder.RegisterTaskDefinition(@"Test", td);

         // Remove the task we just created
         ts.RootFolder.DeleteTask("Test");
      }
   }
}

Alternatively you can use native API or go for Quartz.NET. See this for details.

Way to ng-repeat defined number of times instead of repeating over array?

This is really UGLY, but it works without a controller for either an integer or variable:

integer:

<span ng-repeat="_ in ((_ = []) && (_.length=33) && _) track by $index">{{$index}}</span>

variable:

<span ng-repeat="_ in ((_ = []) && (_.length=myVar) && _) track by $index">{{$index}}</span>

Export data from R to Excel

Another option is the openxlsx-package. It doesn't depend on and can read, edit and write Excel-files. From the description from the package:

openxlsx simplifies the the process of writing and styling Excel xlsx files from R and removes the dependency on Java

Example usage:

library(openxlsx)

# read data from an Excel file or Workbook object into a data.frame
df <- read.xlsx('name-of-your-excel-file.xlsx')

# for writing a data.frame or list of data.frames to an xlsx file
write.xlsx(df, 'name-of-your-excel-file.xlsx')

Besides these two basic functions, the openxlsx-package has a host of other functions for manipulating Excel-files.

For example, with the writeDataTable-function you can create formatted tables in an Excel-file.

Combine multiple JavaScript files into one JS file

If you're running PHP, I recommend Minify because it does combines and minifies on the fly for both CSS and JS. Once you've configured it, just work as normal and it takes care of everything.

addEventListener in Internet Explorer

I'm using this solution and works in IE8 or greater.

if (typeof Element.prototype.addEventListener === 'undefined') {
    Element.prototype.addEventListener = function (e, callback) {
      e = 'on' + e;
      return this.attachEvent(e, callback);
    };
  }

And then:

<button class="click-me">Say Hello</button>

<script>
  document.querySelectorAll('.click-me')[0].addEventListener('click', function () {
    console.log('Hello');
  });
</script>

This will work both IE8 and Chrome, Firefox, etc.

Bash if statement with multiple conditions throws an error

Use -a (for and) and -o (for or) operations.

tldp.org/LDP/Bash-Beginners-Guide/html/sect_07_01.html

Update

Actually you could still use && and || with the -eq operation. So your script would be like this:

my_error_flag=1
my_error_flag_o=1
if [ $my_error_flag -eq 1 ] ||  [ $my_error_flag_o -eq 2 ] || ([ $my_error_flag -eq 1 ] && [ $my_error_flag_o -eq 2 ]); then
      echo "$my_error_flag"
else
    echo "no flag"
fi

Although in your case you can discard the last two expressions and just stick with one or operation like this:

my_error_flag=1
my_error_flag_o=1
if [ $my_error_flag -eq 1 ] ||  [ $my_error_flag_o -eq 2 ]; then
      echo "$my_error_flag"
else
    echo "no flag"
fi

How to pass the button value into my onclick event function?

You can pass the element into the function <input type="button" value="mybutton1" onclick="dosomething(this)">test by passing this. Then in the function you can access the value like this:

function dosomething(element) {
  console.log(element.value);
}

How do I create a right click context menu in Java Swing?

The following code implements a default context menu known from Windows with copy, cut, paste, select all, undo and redo functions. It also works on Linux and Mac OS X:

import javax.swing.*;
import javax.swing.text.JTextComponent;
import javax.swing.undo.UndoManager;
import java.awt.*;
import java.awt.datatransfer.Clipboard;
import java.awt.datatransfer.DataFlavor;
import java.awt.event.KeyAdapter;
import java.awt.event.KeyEvent;
import java.awt.event.MouseAdapter;
import java.awt.event.MouseEvent;

public class DefaultContextMenu extends JPopupMenu
{
    private Clipboard clipboard;

    private UndoManager undoManager;

    private JMenuItem undo;
    private JMenuItem redo;
    private JMenuItem cut;
    private JMenuItem copy;
    private JMenuItem paste;
    private JMenuItem delete;
    private JMenuItem selectAll;

    private JTextComponent textComponent;

    public DefaultContextMenu()
    {
        undoManager = new UndoManager();
        clipboard = Toolkit.getDefaultToolkit().getSystemClipboard();

        addPopupMenuItems();
    }

    private void addPopupMenuItems()
    {
        undo = new JMenuItem("Undo");
        undo.setEnabled(false);
        undo.setAccelerator(KeyStroke.getKeyStroke(KeyEvent.VK_Z, Toolkit.getDefaultToolkit().getMenuShortcutKeyMask()));
        undo.addActionListener(event -> undoManager.undo());
        add(undo);

        redo = new JMenuItem("Redo");
        redo.setEnabled(false);
        redo.setAccelerator(KeyStroke.getKeyStroke(KeyEvent.VK_Y, Toolkit.getDefaultToolkit().getMenuShortcutKeyMask()));
        redo.addActionListener(event -> undoManager.redo());
        add(redo);

        add(new JSeparator());

        cut = new JMenuItem("Cut");
        cut.setEnabled(false);
        cut.setAccelerator(KeyStroke.getKeyStroke(KeyEvent.VK_X, Toolkit.getDefaultToolkit().getMenuShortcutKeyMask()));
        cut.addActionListener(event -> textComponent.cut());
        add(cut);

        copy = new JMenuItem("Copy");
        copy.setEnabled(false);
        copy.setAccelerator(KeyStroke.getKeyStroke(KeyEvent.VK_C, Toolkit.getDefaultToolkit().getMenuShortcutKeyMask()));
        copy.addActionListener(event -> textComponent.copy());
        add(copy);

        paste = new JMenuItem("Paste");
        paste.setEnabled(false);
        paste.setAccelerator(KeyStroke.getKeyStroke(KeyEvent.VK_V, Toolkit.getDefaultToolkit().getMenuShortcutKeyMask()));
        paste.addActionListener(event -> textComponent.paste());
        add(paste);

        delete = new JMenuItem("Delete");
        delete.setEnabled(false);
        delete.setAccelerator(KeyStroke.getKeyStroke(KeyEvent.VK_DELETE, Toolkit.getDefaultToolkit().getMenuShortcutKeyMask()));
        delete.addActionListener(event -> textComponent.replaceSelection(""));
        add(delete);

        add(new JSeparator());

        selectAll = new JMenuItem("Select All");
        selectAll.setEnabled(false);
        selectAll.setAccelerator(KeyStroke.getKeyStroke(KeyEvent.VK_A, Toolkit.getDefaultToolkit().getMenuShortcutKeyMask()));
        selectAll.addActionListener(event -> textComponent.selectAll());
        add(selectAll);
    }

    private void addTo(JTextComponent textComponent)
    {
        textComponent.addKeyListener(new KeyAdapter()
        {
            @Override
            public void keyPressed(KeyEvent pressedEvent)
            {
                if ((pressedEvent.getKeyCode() == KeyEvent.VK_Z)
                        && ((pressedEvent.getModifiersEx() & Toolkit.getDefaultToolkit().getMenuShortcutKeyMask()) != 0))
                {
                    if (undoManager.canUndo())
                    {
                        undoManager.undo();
                    }
                }

                if ((pressedEvent.getKeyCode() == KeyEvent.VK_Y)
                        && ((pressedEvent.getModifiersEx() & Toolkit.getDefaultToolkit().getMenuShortcutKeyMask()) != 0))
                {
                    if (undoManager.canRedo())
                    {
                        undoManager.redo();
                    }
                }
            }
        });

        textComponent.addMouseListener(new MouseAdapter()
        {
            @Override
            public void mousePressed(MouseEvent releasedEvent)
            {
                handleContextMenu(releasedEvent);
            }

            @Override
            public void mouseReleased(MouseEvent releasedEvent)
            {
                handleContextMenu(releasedEvent);
            }
        });

        textComponent.getDocument().addUndoableEditListener(event -> undoManager.addEdit(event.getEdit()));
    }

    private void handleContextMenu(MouseEvent releasedEvent)
    {
        if (releasedEvent.getButton() == MouseEvent.BUTTON3)
        {
            processClick(releasedEvent);
        }
    }

    private void processClick(MouseEvent event)
    {
        textComponent = (JTextComponent) event.getSource();
        textComponent.requestFocus();

        boolean enableUndo = undoManager.canUndo();
        boolean enableRedo = undoManager.canRedo();
        boolean enableCut = false;
        boolean enableCopy = false;
        boolean enablePaste = false;
        boolean enableDelete = false;
        boolean enableSelectAll = false;

        String selectedText = textComponent.getSelectedText();
        String text = textComponent.getText();

        if (text != null)
        {
            if (text.length() > 0)
            {
                enableSelectAll = true;
            }
        }

        if (selectedText != null)
        {
            if (selectedText.length() > 0)
            {
                enableCut = true;
                enableCopy = true;
                enableDelete = true;
            }
        }

        if (clipboard.isDataFlavorAvailable(DataFlavor.stringFlavor) && textComponent.isEnabled())
        {
            enablePaste = true;
        }

        undo.setEnabled(enableUndo);
        redo.setEnabled(enableRedo);
        cut.setEnabled(enableCut);
        copy.setEnabled(enableCopy);
        paste.setEnabled(enablePaste);
        delete.setEnabled(enableDelete);
        selectAll.setEnabled(enableSelectAll);

        // Shows the popup menu
        show(textComponent, event.getX(), event.getY());
    }

    public static void addDefaultContextMenu(JTextComponent component)
    {
        DefaultContextMenu defaultContextMenu = new DefaultContextMenu();
        defaultContextMenu.addTo(component);
    }
}

Usage:

JTextArea textArea = new JTextArea();
DefaultContextMenu.addDefaultContextMenu(textArea);

Now the textArea will have a context menu when it is right-clicked on.

How can I add an item to a IEnumerable<T> collection?

The type IEnumerable<T> does not support such operations. The purpose of the IEnumerable<T> interface is to allow a consumer to view the contents of a collection. Not to modify the values.

When you do operations like .ToList().Add() you are creating a new List<T> and adding a value to that list. It has no connection to the original list.

What you can do is use the Add extension method to create a new IEnumerable<T> with the added value.

items = items.Add("msg2");

Even in this case it won't modify the original IEnumerable<T> object. This can be verified by holding a reference to it. For example

var items = new string[]{"foo"};
var temp = items;
items = items.Add("bar");

After this set of operations the variable temp will still only reference an enumerable with a single element "foo" in the set of values while items will reference a different enumerable with values "foo" and "bar".

EDIT

I contstantly forget that Add is not a typical extension method on IEnumerable<T> because it's one of the first ones that I end up defining. Here it is

public static IEnumerable<T> Add<T>(this IEnumerable<T> e, T value) {
  foreach ( var cur in e) {
    yield return cur;
  }
  yield return value;
}

What's the right way to pass form element state to sibling/parent elements?

Having used React to build an app now, I'd like to share some thoughts to this question I asked half a year ago.

I recommend you to read

The first post is extremely helpful to understanding how you should structure your React app.

Flux answers the question why should you structure your React app this way (as opposed to how to structure it). React is only 50% of the system, and with Flux you get to see the whole picture and see how they constitute a coherent system.

Back to the question.

As for my first solution, it is totally OK to let the handler go the reverse direction, as the data is still going single-direction.

However, whether letting a handler trigger a setState in P can be right or wrong depending on your situation.

If the app is a simple Markdown converter, C1 being the raw input and C2 being the HTML output, it's OK to let C1 trigger a setState in P, but some might argue this is not the recommended way to do it.

However, if the app is a todo list, C1 being the input for creating a new todo, C2 the todo list in HTML, you probably want to handler to go two level up than P -- to the dispatcher, which let the store update the data store, which then send the data to P and populate the views. See that Flux article. Here is an example: Flux - TodoMVC

Generally, I prefer the way described in the todo list example. The less state you have in your app the better.

Fatal error: Class 'SoapClient' not found

For AWS (RHEL):

sudo yum install php56-soap

(56 here is 5.6 PHP version - put your version here).

Installing OpenCV 2.4.3 in Visual C++ 2010 Express

1. Installing OpenCV 2.4.3

First, get OpenCV 2.4.3 from sourceforge.net. Its a self-extracting so just double click to start the installation. Install it in a directory, say C:\.

OpenCV self-extractor

Wait until all files get extracted. It will create a new directory C:\opencv which contains OpenCV header files, libraries, code samples, etc.

Now you need to add the directory C:\opencv\build\x86\vc10\bin to your system PATH. This directory contains OpenCV DLLs required for running your code.

Open Control PanelSystemAdvanced system settingsAdvanced Tab → Environment variables...

enter image description here

On the System Variables section, select Path (1), Edit (2), and type C:\opencv\build\x86\vc10\bin; (3), then click Ok.

On some computers, you may need to restart your computer for the system to recognize the environment path variables.

This will completes the OpenCV 2.4.3 installation on your computer.


2. Create a new project and set up Visual C++

Open Visual C++ and select FileNewProject...Visual C++Empty Project. Give a name for your project (e.g: cvtest) and set the project location (e.g: c:\projects).

New project dialog

Click Ok. Visual C++ will create an empty project.

VC++ empty project

Make sure that "Debug" is selected in the solution configuration combobox. Right-click cvtest and select PropertiesVC++ Directories.

Project property dialog

Select Include Directories to add a new entry and type C:\opencv\build\include.

Include directories dialog

Click Ok to close the dialog.

Back to the Property dialog, select Library Directories to add a new entry and type C:\opencv\build\x86\vc10\lib.

Library directories dialog

Click Ok to close the dialog.

Back to the property dialog, select LinkerInputAdditional Dependencies to add new entries. On the popup dialog, type the files below:

opencv_calib3d243d.lib
opencv_contrib243d.lib
opencv_core243d.lib
opencv_features2d243d.lib
opencv_flann243d.lib
opencv_gpu243d.lib
opencv_haartraining_engined.lib
opencv_highgui243d.lib
opencv_imgproc243d.lib
opencv_legacy243d.lib
opencv_ml243d.lib
opencv_nonfree243d.lib
opencv_objdetect243d.lib
opencv_photo243d.lib
opencv_stitching243d.lib
opencv_ts243d.lib
opencv_video243d.lib
opencv_videostab243d.lib

Note that the filenames end with "d" (for "debug"). Also note that if you have installed another version of OpenCV (say 2.4.9) these filenames will end with 249d instead of 243d (opencv_core249d.lib..etc).

enter image description here

Click Ok to close the dialog. Click Ok on the project properties dialog to save all settings.

NOTE:

These steps will configure Visual C++ for the "Debug" solution. For "Release" solution (optional), you need to repeat adding the OpenCV directories and in Additional Dependencies section, use:

opencv_core243.lib
opencv_imgproc243.lib
...

instead of:

opencv_core243d.lib
opencv_imgproc243d.lib
...

You've done setting up Visual C++, now is the time to write the real code. Right click your project and select AddNew Item...Visual C++C++ File.

Add new source file

Name your file (e.g: loadimg.cpp) and click Ok. Type the code below in the editor:

#include <opencv2/highgui/highgui.hpp>
#include <iostream>

using namespace cv;
using namespace std;

int main()
{
    Mat im = imread("c:/full/path/to/lena.jpg");
    if (im.empty()) 
    {
        cout << "Cannot load image!" << endl;
        return -1;
    }
    imshow("Image", im);
    waitKey(0);
}

The code above will load c:\full\path\to\lena.jpg and display the image. You can use any image you like, just make sure the path to the image is correct.

Type F5 to compile the code, and it will display the image in a nice window.

First OpenCV program

And that is your first OpenCV program!


3. Where to go from here?

Now that your OpenCV environment is ready, what's next?

  1. Go to the samples dir → c:\opencv\samples\cpp.
  2. Read and compile some code.
  3. Write your own code.

How can I get the file name from request.FILES?

NOTE if you are using python 3.x:

request.FILES is a multivalue dictionary like object that keeps the files uploaded through an upload file button. Say in your html code the name of the button (type="file") is "myfile" so "myfile" will be the key in this dictionary. If you uploaded one file, then the value for this key will be only one and if you uploaded multiple files, then you will have multiple values for that specific key. If you use request.FILES['myfile'] you will get the first or last value (I cannot say for sure). This is fine if you only uploaded one file, but if you want to get all files you should do this:

list=[] #myfile is the key of a multi value dictionary, values are the uploaded files
for f in request.FILES.getlist('myfile'): #myfile is the name of your html file button
    filename = f.name
    list.append(filename)

of course one can squeeze the whole thing in one line, but this is easy to understand

Sorting dropdown alphabetically in AngularJS

var module = angular.module("example", []);

module.controller("orderByController", function ($scope) {
    $scope.orderByValue = function (value) {
        return value;
    };

    $scope.items = ["c", "b", "a"];
    $scope.objList = [
        {
            "name": "c"
        }, {
            "name": "b"
        }, {
            "name": "a"
        }];
        $scope.item = "b";
    });

http://jsfiddle.net/Nfv42/65/

jQuery DIV click, with anchors

<div class="info">
   <h2>Takvim</h2>
   <a href="item-list.php"> Click Me !</a>
</div>


$(document).delegate("div.info", "click", function() {
   window.location = $(this).find("a").attr("href");
});

How to get param from url in angular 4?

use paramMap

This will provide param names and their values

//http://localhost:4200/categories/1
//{ path: 'categories/:category', component: CategoryComponent },

import { ActivatedRoute } from '@angular/router';

constructor(private route: ActivatedRoute) { }

ngOnInit() {

  this.route.paramMap.subscribe(params => {
        console.log(params)
  })
}

Why I've got no crontab entry on OS X when using vim?

Other option is not to use crontab -e at all. Instead I used:

(crontab -l && echo "1 1  * * *  /path/to/my/script.sh") | crontab -

Notice that whatever you print before | crontab - will replace the entire crontab file, so use crontab -l && echo "<your new schedule>" to get the previous content and the new schedule.

How to make git mark a deleted and a new file as a file move?

The other answers already cover that you can simply git add NEW && git rm OLD in order to make git recognize the move.

However, if you have already modified the file in the working directory, the add+rm approach will add the modifications to the index, which may be undesired in some cases (e.g. in case of substantial modifications, git might not recognize anymore that it is a file rename).

Let's assume you want to add the rename to the index, but not any modifications. The obvious way to achieve this, is to do a back and forth rename mv NEW OLD && git mv OLD NEW.

But there is also a (slighty more complicated) way to do this directly in the index without renaming the file in the working tree:

info=$(git ls-files -s -- "OLD" | cut -d' ' -f-2 | tr ' ' ,)
git update-index --add --cacheinfo "$info,NEW" &&
git rm --cached "$old"

This can also be put as an alias in your ~/.gitconfig:

[alias]
    mv-index = "!f() { \
      old=\"$1\"; \
      new=\"$2\"; \
      info=$(git ls-files -s -- \"$old\" | cut -d' ' -f-2 | tr ' ' ,); \
      git update-index --add --cacheinfo \"$info,$new\" && \
      git rm --cached \"$old\"; \
    }; f"

SET NOCOUNT ON usage

SET NOCOUNT ON;

This line of code is used in SQL for not returning the number rows affected in the execution of the query. If we don't require the number of rows affected, we can use this as this would help in saving memory usage and increase the speeed of execution of the query.

Difference between Role and GrantedAuthority in Spring Security

Like others have mentioned, I think of roles as containers for more granular permissions.

Although I found the Hierarchy Role implementation to be lacking fine control of these granular permission.
So I created a library to manage the relationships and inject the permissions as granted authorities in the security context.

I may have a set of permissions in the app, something like CREATE, READ, UPDATE, DELETE, that are then associated with the user's Role.

Or more specific permissions like READ_POST, READ_PUBLISHED_POST, CREATE_POST, PUBLISH_POST

These permissions are relatively static, but the relationship of roles to them may be dynamic.

Example -

@Autowired 
RolePermissionsRepository repository;

public void setup(){
  String roleName = "ROLE_ADMIN";
  List<String> permissions = new ArrayList<String>();
  permissions.add("CREATE");
  permissions.add("READ");
  permissions.add("UPDATE");
  permissions.add("DELETE");
  repository.save(new RolePermissions(roleName, permissions));
}

You may create APIs to manage the relationship of these permissions to a role.

I don't want to copy/paste another answer, so here's the link to a more complete explanation on SO.
https://stackoverflow.com/a/60251931/1308685

To re-use my implementation, I created a repo. Please feel free to contribute!
https://github.com/savantly-net/spring-role-permissions

Is there a way to use shell_exec without waiting for the command to complete?

On Windows 2003, to call another script without waiting, I used this:

$commandString = "start /b c:\\php\\php.EXE C:\\Inetpub\\wwwroot\\mysite.com\\phpforktest.php --passmsg=$testmsg"; 
pclose(popen($commandString, 'r'));

This only works AFTER giving changing permissions on cmd.exe - add Read and Execute for IUSR_YOURMACHINE (I also set write to Deny).

Failure [INSTALL_FAILED_ALREADY_EXISTS] when I tried to update my application

If u still facing problem then try to uninstall application using command prompt. just add command adb uninstall com.example.yourpackagename then try to re-install again.It works!

How to convert milliseconds to "hh:mm:ss" format?

 public String millsToDateFormat(long mills) {

    Date date = new Date(mills);
    DateFormat formatter = new SimpleDateFormat("HH:mm:ss");
    String dateFormatted = formatter.format(date);
    return dateFormatted; //note that it will give you the time in GMT+0
}

How to handle Uncaught (in promise) DOMException: The play() request was interrupted by a call to pause()

I don't know if this is still actual for you, but I still leave my comment so maybe it will help somebody else. I had same issue, and the solution proposed by @dighan on bountysource.com/issues/ solved it for me.

So here is the code that solved my problem:

var media = document.getElementById("YourVideo");
const playPromise = media.play();
if (playPromise !== null){
    playPromise.catch(() => { media.play(); })
}

It still throws an error into console, but at least the video is playing :)

Generating a PNG with matplotlib when DISPLAY is undefined

I found this snippet to work well when switching between X and no-X environments.

import os
import matplotlib as mpl
if os.environ.get('DISPLAY','') == '':
    print('no display found. Using non-interactive Agg backend')
    mpl.use('Agg')
import matplotlib.pyplot as plt

Apply style to cells of first row

Below works for first tr of the table under thead

table thead tr:first-child {
   background: #f2f2f2;
}

And this works for the first tr of thead and tbody both:

table thead tbody tr:first-child {
   background: #f2f2f2;
}

Swift - Integer conversion to Hours/Minutes/Seconds

SWIFT 3.0 solution based roughly on the one above using extensions.

extension CMTime {
  var durationText:String {
    let totalSeconds = CMTimeGetSeconds(self)
    let hours:Int = Int(totalSeconds.truncatingRemainder(dividingBy: 86400) / 3600)
    let minutes:Int = Int(totalSeconds.truncatingRemainder(dividingBy: 3600) / 60)
    let seconds:Int = Int(totalSeconds.truncatingRemainder(dividingBy: 60))

    if hours > 0 {
        return String(format: "%i:%02i:%02i", hours, minutes, seconds)
    } else {
        return String(format: "%02i:%02i", minutes, seconds)
    }

  }
}

Use it with AVPlayer calling it like this?

 let dTotalSeconds = self.player.currentTime()
 playingCurrentTime = dTotalSeconds.durationText

How to subtract date/time in JavaScript?

You can just substract two date objects.

var d1 = new Date(); //"now"
var d2 = new Date("2011/02/01")  // some date
var diff = Math.abs(d1-d2);  // difference in milliseconds

How to pause / sleep thread or process in Android?

Or you could use:

android.os.SystemClock.sleep(checkEvery)

which has the advantage of not requiring a wrapping try ... catch.

"Invalid form control" only in Google Chrome

I got this error message when I entered a number (999999) that was out of the range I'd set for the form.

<input type="number" ng-model="clipInMovieModel" id="clipInMovie" min="1" max="10000">

React setState not updating state

setState() is usually asynchronous, which means that at the time you console.log the state, it's not updated yet. Try putting the log in the callback of the setState() method. It is executed after the state change is complete:

this.setState({ dealersOverallTotal: total }, () => {
  console.log(this.state.dealersOverallTotal, 'dealersOverallTotal1');
}); 

How can I get the current PowerShell executing file?

I would argue that there is a better method, by setting the scope of the variable $MyInvocation.MyCommand.Path:

ex> $script:MyInvocation.MyCommand.Name

This method works in all circumstances of invocation:

EX: Somescript.ps1

function printme () {
    "In function:"
    ( "MyInvocation.ScriptName: " + [string]($MyInvocation.ScriptName) )
    ( "script:MyInvocation.MyCommand.Name: " + [string]($script:MyInvocation.MyCommand.Name) )
    ( "MyInvocation.MyCommand.Name: " + [string]($MyInvocation.MyCommand.Name) )
}
"Main:"
( "MyInvocation.ScriptName: " + [string]($MyInvocation.ScriptName) )
( "script:MyInvocation.MyCommand.Name: " + [string]($script:MyInvocation.MyCommand.Name) )
( "MyInvocation.MyCommand.Name: " + [string]($MyInvocation.MyCommand.Name) )
" "
printme
exit

OUTPUT:

PS> powershell C:\temp\test.ps1
Main:
MyInvocation.ScriptName:
script:MyInvocation.MyCommand.Name: test.ps1
MyInvocation.MyCommand.Name: test.ps1

In function:
MyInvocation.ScriptName: C:\temp\test.ps1
script:MyInvocation.MyCommand.Name: test.ps1
MyInvocation.MyCommand.Name: printme

Notice how the above accepted answer does NOT return a value when called from Main. Also, note that the above accepted answer returns the full path when the question requested the script name only. The scoped variable works in all places.

Also, if you did want the full path, then you would just call:

$script:MyInvocation.MyCommand.Path

Building a fat jar using maven

You can use the onejar-maven-plugin for packaging. Basically, it assembles your project and its dependencies in as one jar, including not just your project jar file, but also all external dependencies as a "jar of jars", e.g.

<build>
    <plugins>
        <plugin>
            <groupId>com.jolira</groupId>
            <artifactId>onejar-maven-plugin</artifactId>
                <version>1.4.4</version>
                <executions>
                    <execution>
                        <goals>
                            <goal>one-jar</goal>
                        </goals>
                    </execution>
                </executions>
        </plugin>
    </plugins>
</build>

Note 1: Configuration options is available at the project home page.

Note 2: For one reason or the other, the onejar-maven-plugin project is not published at Maven Central. However jolira.com tracks the original project and publishes it to with the groupId com.jolira.

Why do I keep getting 'SVN: Working Copy XXXX locked; try performing 'cleanup'?

I've had a lot of issues with SVN before and one thing that has definitely caused me problems is modifying files outside of Eclipse or manually deleting folders (which contains the .svn folders), that has probably given me the most trouble.

edit You should also be careful not to interrupt SVN operations, though sometimes a bug may occur and this could cause the .lock file to not be removed, and hence your error.

How can I get the current date and time in the terminal and set a custom command in the terminal for it?

The command is date

To customise the output there are a myriad of options available, see date --help for a list.

For example, date '+%A %W %Y %X' gives Tuesday 34 2013 08:04:22 which is the name of the day of the week, the week number, the year and the time.

SQL Server: Maximum character length of object names

You can also use this script to figure out more info:

EXEC sp_server_info

The result will be something like that:

attribute_id | attribute_name        | attribute_value
-------------|-----------------------|-----------------------------------
           1 | DBMS_NAME             | Microsoft SQL Server
           2 | DBMS_VER              | Microsoft SQL Server 2012 - 11.0.6020.0
          10 | OWNER_TERM            | owner
          11 | TABLE_TERM            | table
          12 | MAX_OWNER_NAME_LENGTH | 128
          13 | TABLE_LENGTH          | 128
          14 | MAX_QUAL_LENGTH       | 128
          15 | COLUMN_LENGTH         | 128
          16 | IDENTIFIER_CASE       | MIXED
           ?  ?                       ?
           ?  ?                       ?
           ?  ?                       ?

How to make phpstorm display line numbers by default?

Just now found where is it on Windows. Its View -> Active Editor -> Show Line Numbers (changes only for current document) and File -> Settings -> Editor -> Appearance -> Show Line Numbers (for all documents)

For Mac Version go to PhpStorm -> Preferences in menu. In the preference window go to IDE settings -> Editor -> Appearance -> Show Line Numbers (To change setting for all documents)

OR if you want to quickly set show line number PER CURRENT WINDOW even easier - right click on the long white column (where breakpoints are set) then select Show Line Numbers.

enter image description here

Red dot on the screenshot is a place where you have to click

How to get current available GPUs in tensorflow?

In TensorFlow Core v2.3.0, the following code should work.

import tensorflow as tf
visible_devices = tf.config.get_visible_devices()
for devices in visible_devices:
  print(devices)

Depending on your environment, this code will produce flowing results.

PhysicalDevice(name='/physical_device:CPU:0', device_type='CPU') PhysicalDevice(name='/physical_device:GPU:0', device_type='GPU')

How to pipe list of files returned by find command to cat to view all the files

Are you trying to find text in files? You can simply use grep for that...

grep searchterm *

What is the difference between "SMS Push" and "WAP Push"?

An SMS Push is a message to tell the terminal to initiate the session. This happens because you can't initiate an IP session simply because you don't know the IP Adress of the mobile terminal. Mostly used to send a few lines of data to end recipient, to the effect of sending information, or reminding of events.

WAP Push is an SMS within the header of which is included a link to a WAP address. On receiving a WAP Push, the compatible mobile handset automatically gives the user the option to access the WAP content on his handset. The WAP Push directs the end-user to a WAP address where content is stored ready for viewing or downloading onto the handset. This wap address may be a page or a WAP site.

The user may “take action” by using a developer-defined soft-key to immediately activate an application to accomplish a specific task, such as downloading a picture, making a purchase, or responding to a marketing offer.

How to remove multiple deleted files in Git repository

Yes, git rm <filename> will stage the deleted state of a file, where <filename> could be a glob pattern:

$ git rm modules/welcome/language/*/kaimonokago_lang.php
rm modules/welcome/language/english/kaimonokago_lang.php
rm modules/welcome/language/french/kaimonokago_lang.php
rm modules/welcome/language/german/kaimonokago_lang.php
rm modules/welcome/language/norwegian/kaimonokago_lang.php

$ git status
# On branch master
# Changes to be committed:
#   (use "git reset HEAD <file>..." to unstage)
#
#       deleted:    modules/welcome/language/english/kaimonokago_lang.php
#       ...

Then, you can commit.

git commit -a will do this in one go, if you want.

You can also use git add -u to stage all the changes, including all the deleted files, then commit.

call a function in success of datatable ajax call

Maybe it's not exactly what you want to do, but using the ajax complete solved my problem of hiding a spinner when the ajax call returned.

So it would look something like this

var table = $('#example').DataTable( {
    "ajax": {
            "type" : "GET",
            "url" : "ajax.php",
            "dataSrc": "",
            "success": function () {
                alert("Done!");
            }       
    },
    "columns": [
            { "data": "name" },
            { "data": "position" },
            { "data": "office" },
            { "data": "extn" },
            { "data": "start_date" },
            { "data": "salary" }            
        ]
    } );

Refresh/reload the content in Div using jquery/ajax

I know the topic is old, but you can declare the Ajax as a variable, then use a function to call the variable on the desired content. Keep in mind you are calling what you have in the Ajax if you want a different elements from the Ajax you need to specify it.

Example:

Var infogen = $.ajax({'your query')};

$("#refresh").click(function(){
  infogen;
  console.log("to verify");
});    

Hope helps

if not try:

$("#refresh").click(function(){
      loca.tion.reload();
      console.log("to verify");
    });    

gitbash command quick reference

You should accept Mike Gossland's answer, but it can be improved a little. Try this in Git Bash:

 ls -1F /bin | grep '\*$' | grep -v '\.dll\*$' | sed 's/\*$\|\.exe//g'

Explanation:

List on 1 line, decorated with trailing * for executables, all files in bin. Keep only those with the trailing *s, but NOT ending with .dll*, then replace all ending asterisks or ".exe" with nothing.

This gives you a clean list of all the GitBash commands.

Why doesn't Java allow overriding of static methods?

Well... the answer is NO if you think from the perspective of how an overriden method should behave in Java. But, you don't get any compiler error if you try to override a static method. That means, if you try to override, Java doesn't stop you doing that; but you certainly don't get the same effect as you get for non-static methods. Overriding in Java simply means that the particular method would be called based on the run time type of the object and not on the compile time type of it (which is the case with overriden static methods). Okay... any guesses for the reason why do they behave strangely? Because they are class methods and hence access to them is always resolved during compile time only using the compile time type information. Accessing them using object references is just an extra liberty given by the designers of Java and we should certainly not think of stopping that practice only when they restrict it :-)

Example: let's try to see what happens if we try overriding a static method:-

class SuperClass {
// ......
public static void staticMethod() {
    System.out.println("SuperClass: inside staticMethod");
}
// ......
}

public class SubClass extends SuperClass {
// ......
// overriding the static method
public static void staticMethod() {
    System.out.println("SubClass: inside staticMethod");
}

// ......
public static void main(String[] args) {
    // ......
    SuperClass superClassWithSuperCons = new SuperClass();
    SuperClass superClassWithSubCons = new SubClass();
    SubClass subClassWithSubCons = new SubClass();

    superClassWithSuperCons.staticMethod();
    superClassWithSubCons.staticMethod();
    subClassWithSubCons.staticMethod();
    // ...
}
}

Output:-
SuperClass: inside staticMethod
SuperClass: inside staticMethod
SubClass: inside staticMethod

Notice the second line of the output. Had the staticMethod been overriden this line should have been identical to the third line as we're invoking the 'staticMethod()' on an object of Runtime Type as 'SubClass' and not as 'SuperClass'. This confirms that the static methods are always resolved using their compile time type information only.

How to keep one variable constant with other one changing with row in excel

=(B0+4)/($A$0)

$ means keep same (press a few times F4 after typing A4 to flip through combos quick!)

AngularJS POST Fails: Response for preflight has invalid HTTP status code 404

You have enabled CORS and enabled Access-Control-Allow-Origin : * in the server.If still you get GET method working and POST method is not working then it might be because of the problem of Content-Type and data problem.

First AngularJS transmits data using Content-Type: application/json which is not serialized natively by some of the web servers (notably PHP). For them we have to transmit the data as Content-Type: x-www-form-urlencoded

Example :-

        $scope.formLoginPost = function () {
            $http({
                url: url,
                method: "POST",
                data: $.param({ 'username': $scope.username, 'Password': $scope.Password }),
                headers: { 'Content-Type': 'application/x-www-form-urlencoded' }
            }).then(function (response) {
                // success
                console.log('success');
                console.log("then : " + JSON.stringify(response));
            }, function (response) { // optional
                // failed
                console.log('failed');
                console.log(JSON.stringify(response));
            });
        };

Note : I am using $.params to serialize the data to use Content-Type: x-www-form-urlencoded. Alternatively you can use the following javascript function

function params(obj){
    var str = "";
    for (var key in obj) {
        if (str != "") {
            str += "&";
        }
        str += key + "=" + encodeURIComponent(obj[key]);
    }
    return str;
}

and use params({ 'username': $scope.username, 'Password': $scope.Password }) to serialize it as the Content-Type: x-www-form-urlencoded requests only gets the POST data in username=john&Password=12345 form.

Add CSS class to a div in code behind

To ADD classes to html elements see how to add css class to html generic control div?. There are answers similar to those given here but showing how to add classes to html elements.

C programming: Dereferencing pointer to incomplete type error

You haven't defined struct stasher_file by your first definition. What you have defined is an nameless struct type and a variable stasher_file of that type. Since there's no definition for such type as struct stasher_file in your code, the compiler complains about incomplete type.

In order to define struct stasher_file, you should have done it as follows

struct stasher_file {
 char name[32];
 int  size;
 int  start;
 int  popularity;
};

Note where the stasher_file name is placed in the definition.

Redirect from asp.net web api post action

    [HttpGet]
    public RedirectResult Get()
    {
        return RedirectPermanent("https://www.google.com");
    }

How to print Unicode character in Python?

Considering that this is the first stack overflow result when google searching this topic, it bears mentioning that prefixing u to unicode strings is optional in Python 3. (Python 2 example was copied from the top answer)

Python 3 (both work):

print('\u0420\u043e\u0441\u0441\u0438\u044f')
print(u'\u0420\u043e\u0441\u0441\u0438\u044f')

Python 2:

print u'\u0420\u043e\u0441\u0441\u0438\u044f'

How can I retrieve a table from stored procedure to a datatable?

Explaining if any one want to send some parameters while calling stored procedure as below,

using (SqlConnection con = new SqlConnection(connetionString))
            {
                using (var command = new SqlCommand(storedProcName, con))
                {
                    foreach (var item in sqlParams)
                    {
                        item.Direction = ParameterDirection.Input;
                        item.DbType = DbType.String;
                        command.Parameters.Add(item);
                    }
                    command.CommandType = CommandType.StoredProcedure;
                    using (var adapter = new SqlDataAdapter(command))
                    {
                        adapter.Fill(dt);
                    }
                }
            }

Align DIV's to bottom or baseline

Seven years later searches for vertical alignment still bring up this question, so I'll post another solution we have available to us now: flexbox positioning. Just set display:flex; justify-content: flex-end; flex-direction: column on the parent div (demonstrated in this fiddle as well):

#parentDiv
{
  display: flex;
  justify-content: flex-end;
  flex-direction: column;
  width:300px;
  height:300px;
  background-color:#ccc;
  background-repeat:repeat
}

How to change current Theme at runtime in Android

Instead of

getApplication().setTheme(R.style.BlackTheme);

use

setTheme(R.style.BlackTheme);

My code: in onCreate() method:

super.onCreate(savedInstanceState);

if(someExpression) {
    setTheme(R.style.OneTheme);
} else {
    setTheme(R.style.AnotherTheme);
}

setContentView(R.layout.activity_some_layout);

Somewhere (for example, on a button click):

YourActivity.this.recreate();

You have to recreate activity, otherwise - change won't happen

Update div with jQuery ajax response html

It's also possible to use jQuery's .load()

$('#submitform').click(function() {
  $('#showresults').load('getinfo.asp #showresults', {
    txtsearch: $('#appendedInputButton').val()
  }, function() {
    // alert('Load was performed.')
    // $('#showresults').slideDown('slow')
  });
});

unlike $.get(), allows us to specify a portion of the remote document to be inserted. This is achieved with a special syntax for the url parameter. If one or more space characters are included in the string, the portion of the string following the first space is assumed to be a jQuery selector that determines the content to be loaded.

We could modify the example above to use only part of the document that is fetched:

$( "#result" ).load( "ajax/test.html #container" );

When this method executes, it retrieves the content of ajax/test.html, but then jQuery parses the returned document to find the element with an ID of container. This element, along with its contents, is inserted into the element with an ID of result, and the rest of the retrieved document is discarded.

When to use throws in a Java method declaration?

This is not an answer, but a comment, but I could not write a comment with a formatted code, so here is the comment.

Lets say there is

public static void main(String[] args) {
  try {
    // do nothing or throw a RuntimeException
    throw new RuntimeException("test");
  } catch (Exception e) {
    System.out.println(e.getMessage());
    throw e;
  }
}

The output is

test
Exception in thread "main" java.lang.RuntimeException: test
    at MyClass.main(MyClass.java:10)

That method does not declare any "throws" Exceptions, but throws them! The trick is that the thrown exceptions are RuntimeExceptions (unchecked) that are not needed to be declared on the method. It is a bit misleading for the reader of the method, since all she sees is a "throw e;" statement but no declaration of the throws exception

Now, if we have

public static void main(String[] args) throws Exception {
  try {
    throw new Exception("test");
  } catch (Exception e) {
    System.out.println(e.getMessage());
    throw e;
  }
}

We MUST declare the "throws" exceptions in the method otherwise we get a compiler error.

Table border left and bottom

Give a class .border-lb and give this CSS

.border-lb {border: 1px solid #ccc; border-width: 0 0 1px 1px;}

And the HTML

<table width="770">
  <tr>
    <td class="border-lb">picture (border only to the left and bottom ) </td>
    <td>text</td>
  </tr>
  <tr>
    <td>text</td>
    <td class="border-lb">picture (border only to the left and bottom) </td>
  </tr>
</table>

Screenshot

Fiddle: http://jsfiddle.net/FXMVL/

Node.js server that accepts POST requests

The following code shows how to read values from an HTML form. As @pimvdb said you need to use the request.on('data'...) to capture the contents of the body.

const http = require('http')

const server = http.createServer(function(request, response) {
  console.dir(request.param)

  if (request.method == 'POST') {
    console.log('POST')
    var body = ''
    request.on('data', function(data) {
      body += data
      console.log('Partial body: ' + body)
    })
    request.on('end', function() {
      console.log('Body: ' + body)
      response.writeHead(200, {'Content-Type': 'text/html'})
      response.end('post received')
    })
  } else {
    console.log('GET')
    var html = `
            <html>
                <body>
                    <form method="post" action="http://localhost:3000">Name: 
                        <input type="text" name="name" />
                        <input type="submit" value="Submit" />
                    </form>
                </body>
            </html>`
    response.writeHead(200, {'Content-Type': 'text/html'})
    response.end(html)
  }
})

const port = 3000
const host = '127.0.0.1'
server.listen(port, host)
console.log(`Listening at http://${host}:${port}`)


If you use something like Express.js and Bodyparser then it would look like this since Express will handle the request.body concatenation

var express = require('express')
var fs = require('fs')
var app = express()

app.use(express.bodyParser())

app.get('/', function(request, response) {
  console.log('GET /')
  var html = `
    <html>
        <body>
            <form method="post" action="http://localhost:3000">Name: 
                <input type="text" name="name" />
                <input type="submit" value="Submit" />
            </form>
        </body>
    </html>`
  response.writeHead(200, {'Content-Type': 'text/html'})
  response.end(html)
})

app.post('/', function(request, response) {
  console.log('POST /')
  console.dir(request.body)
  response.writeHead(200, {'Content-Type': 'text/html'})
  response.end('thanks')
})

port = 3000
app.listen(port)
console.log(`Listening at http://localhost:${port}`)

CSS media query to target only iOS devices

Yes, you can.

@supports (-webkit-touch-callout: none) {
  /* CSS specific to iOS devices */ 
}

@supports not (-webkit-touch-callout: none) {
  /* CSS for other than iOS devices */ 
}

YMMV.

It works because only Safari Mobile implements -webkit-touch-callout: https://developer.mozilla.org/en-US/docs/Web/CSS/-webkit-touch-callout

Please note that @supports does not work in IE. IE will skip both of the above @support blocks above. To find out more see https://hacks.mozilla.org/2016/08/using-feature-queries-in-css/. It is recommended to not use @supports not because of this.

What about Chrome or Firefox on iOS? The reality is these are just skins over the WebKit rendering engine. Hence the above works everywhere on iOS as long as iOS policy does not change. See 2.5.6 in App Store Review Guidelines.

Warning: iOS may remove support for this in any new iOS release in the coming years. You SHOULD try a bit harder to not need the above CSS. An earlier version of this answer used -webkit-overflow-scrolling but a new iOS version removed it. As a commenter pointed out, there are other options to choose from: Go to Supported CSS Properties and search for "Safari on iOS".

How can I run NUnit tests in Visual Studio 2017?

Install the NUnit and NunitTestAdapter package to your test projects from Manage Nunit packages. to perform the same: 1 Right-click on menu Project ? click "Manage NuGet Packages". 2 Go to the "Browse" tab -> Search for the Nunit (or any other package which you want to install) 3 Click on the Package -> A side screen will open "Select the project and click on the install.

Perform your tasks (Add code) If your project is a Console application then a play/run button is displayed on the top click on that any your application will run and If your application is a class library Go to the Test Explorer and click on "Run All" option.

How is Docker different from a virtual machine?

Good answers. Just to get an image representation of container vs VM, have a look at the one below.

enter image description here

Source

Android EditText Hint

You can use the concept of selector. onFocus removes the hint.

android:hint="Email"

So when TextView has focus, or has user input (i.e. not empty) the hint will not display.

Is there a printf converter to print in binary format?

None of the previously posted answers are exactly what I was looking for, so I wrote one. It is super simple to use %B with the printf!

/*
 * File:   main.c
 * Author: Techplex.Engineer
 *
 * Created on February 14, 2012, 9:16 PM
 */

#include <stdio.h>
#include <stdlib.h>
#include <printf.h>
#include <math.h>
#include <string.h>

static int printf_arginfo_M(const struct printf_info *info, size_t n, int *argtypes)
{
    /* "%M" always takes one argument, a pointer to uint8_t[6]. */
    if (n > 0) {
        argtypes[0] = PA_POINTER;
    }
    return 1;
}

static int printf_output_M(FILE *stream, const struct printf_info *info, const void *const *args)
{
    int value = 0;
    int len;

    value = *(int **) (args[0]);

    // Beginning of my code ------------------------------------------------------------
    char buffer [50] = "";  // Is this bad?
    char buffer2 [50] = "";  // Is this bad?
    int bits = info->width;
    if (bits <= 0)
        bits = 8;  // Default to 8 bits

    int mask = pow(2, bits - 1);
    while (mask > 0) {
        sprintf(buffer, "%s", ((value & mask) > 0 ? "1" : "0"));
        strcat(buffer2, buffer);
        mask >>= 1;
    }
    strcat(buffer2, "\n");
    // End of my code --------------------------------------------------------------
    len = fprintf(stream, "%s", buffer2);
    return len;
}

int main(int argc, char** argv)
{
    register_printf_specifier('B', printf_output_M, printf_arginfo_M);

    printf("%4B\n", 65);

    return EXIT_SUCCESS;
}

Find all stored procedures that reference a specific column in some table

You can use the below query to identify the values. But please keep in mind that this will not give you the results from encrypted stored procedure.

SELECT DISTINCT OBJECT_NAME(comments.id) OBJECT_NAME
    ,objects.type_desc
FROM syscomments comments
    ,sys.objects objects
WHERE comments.id = objects.object_id
    AND TEXT LIKE '%CreatedDate%'
ORDER BY 1

100% width Twitter Bootstrap 3 template

This is the complete basic structure for 100% width layout in Bootstrap v3.0.0. You shouldn't wrap your <div class="row"> with container class. Cause container class will take lots of margin and this will not provide you full screen (100% width) layout where bootstrap has removed container-fluid class from their mobile-first version v3.0.0.

So just start writing <div class="row"> without container class and you are ready to go with 100% width layout.

<!DOCTYPE html>
<html>
  <head>
    <title>Bootstrap Basic 100% width Structure</title>
    <meta name="viewport" content="width=device-width, initial-scale=1.0">
    <!-- Bootstrap -->
    <link rel="stylesheet" href="http://netdna.bootstrapcdn.com/bootstrap/3.0.0/css/bootstrap.min.css">

<!-- HTML5 shim and Respond.js IE8 support of HTML5 elements and media queries -->
<!--[if lt IE 9]>
  <script src="http://getbootstrap.com/assets/js/html5shiv.js"></script>
  <script src="http://getbootstrap.com/assets/js/respond.min.js"></script>
<![endif]-->
<style>
    .red{
        background-color: red;
    }
    .green{
        background-color: green;
    }
</style>
</head>
<body>
    <div class="row">
        <div class="col-md-3 red">Test content</div>
        <div class="col-md-9 green">Another Content</div>
    </div>
    <!-- jQuery (necessary for Bootstrap's JavaScript plugins) -->
    <script src="//code.jquery.com/jquery.js"></script>
    <!-- Include all compiled plugins (below), or include individual files as needed -->
    <script src="http://netdna.bootstrapcdn.com/bootstrap/3.0.0/js/bootstrap.min.js"></script>
</body>
</html>

To see the result by yourself I have created a bootply. See the live output there. http://bootply.com/82136 And the complete basic bootstrap 3 100% width layout I have created a gist. you can use that. Get the gist from here

Reply me if you need more further assistance. Thanks.

Task continuation on UI thread

Call the continuation with TaskScheduler.FromCurrentSynchronizationContext():

    Task UITask= task.ContinueWith(() =>
    {
     this.TextBlock1.Text = "Complete"; 
    }, TaskScheduler.FromCurrentSynchronizationContext());

This is suitable only if the current execution context is on the UI thread.

What is the difference between IQueryable<T> and IEnumerable<T>?

First of all, IQueryable<T> extends the IEnumerable<T> interface, so anything you can do with a "plain" IEnumerable<T>, you can also do with an IQueryable<T>.

IEnumerable<T> just has a GetEnumerator() method that returns an Enumerator<T> for which you can call its MoveNext() method to iterate through a sequence of T.

What IQueryable<T> has that IEnumerable<T> doesn't are two properties in particular—one that points to a query provider (e.g., a LINQ to SQL provider) and another one pointing to a query expression representing the IQueryable<T> object as a runtime-traversable abstract syntax tree that can be understood by the given query provider (for the most part, you can't give a LINQ to SQL expression to a LINQ to Entities provider without an exception being thrown).

The expression can simply be a constant expression of the object itself or a more complex tree of a composed set of query operators and operands. The query provider's IQueryProvider.Execute() or IQueryProvider.CreateQuery() methods are called with an Expression passed to it, and then either a query result or another IQueryable is returned, respectively.

Removing trailing newline character from fgets() input

The steps to remove the newline character in the perhaps most obvious way:

  1. Determine the length of the string inside NAME by using strlen(), header string.h. Note that strlen() does not count the terminating \0.
size_t sl = strlen(NAME);

  1. Look if the string begins with or only includes one \0 character (empty string). In this case sl would be 0 since strlen() as I said above doesn´t count the \0 and stops at the first occurrence of it:
if(sl == 0)
{
   // Skip the newline replacement process.
}

  1. Check if the last character of the proper string is a newline character '\n'. If this is the case, replace \n with a \0. Note that index counts start at 0 so we will need to do NAME[sl - 1]:
if(NAME[sl - 1] == '\n')
{
   NAME[sl - 1] = '\0';
}

Note if you only pressed Enter at the fgets() string request (the string content was only consisted of a newline character) the string in NAME will be an empty string thereafter.


  1. We can combine step 2. and 3. together in just one if-statement by using the logic operator &&:
if(sl > 0 && NAME[sl - 1] == '\n')
{
   NAME[sl - 1] = '\0';
}

  1. The finished code:
size_t sl = strlen(NAME);
if(sl > 0 && NAME[sl - 1] == '\n')
{
   NAME[sl - 1] = '\0';
}

If you rather like a function for use this technique by handling fgets output strings in general without retyping each and every time, here is fgets_newline_kill:

void fgets_newline_kill(char a[])
{
    size_t sl = strlen(a);

    if(sl > 0 && a[sl - 1] == '\n')
    {
       a[sl - 1] = '\0';
    }
}

In your provided example, it would be:

printf("Enter your Name: ");

if (fgets(Name, sizeof Name, stdin) == NULL) {
    fprintf(stderr, "Error reading Name.\n");
    exit(1);
}
else {
    fgets_newline_kill(NAME);
}

Note that this method does not work if the input string has embedded \0s in it. If that would be the case strlen() would only return the amount of characters until the first \0. But this isn´t quite a common approach, since the most string-reading functions usually stop at the first \0 and take the string until that null character.

Aside from the question on its own. Try to avoid double negations that make your code unclearer: if (!(fgets(Name, sizeof Name, stdin) != NULL) {}. You can simply do if (fgets(Name, sizeof Name, stdin) == NULL) {}.

Objective-C: Reading a file line by line

A lot of these answers are long chunks of code or they read in the entire file. I like to use the c methods for this very task.

FILE* file = fopen("path to my file", "r");

size_t length;
char *cLine = fgetln(file,&length);

while (length>0) {
    char str[length+1];
    strncpy(str, cLine, length);
    str[length] = '\0';

    NSString *line = [NSString stringWithFormat:@"%s",str];        
    % Do what you want here.

    cLine = fgetln(file,&length);
}

Note that fgetln will not keep your newline character. Also, We +1 the length of the str because we want to make space for the NULL termination.

How to debug on a real device (using Eclipse/ADT)

With an Android-powered device, you can develop and debug your Android applications just as you would on the emulator.

1. Declare your application as "debuggable" in AndroidManifest.xml.

<application
    android:debuggable="true"
    ... >
    ...
</application>

2. On your handset, navigate to Settings > Security and check Unknown sources

enter image description here

3. Go to Settings > Developer Options and check USB debugging
Note that if Developer Options is invisible you will need to navigate to Settings > About Phone and tap on Build number several times until you are notified that it has been unlocked.

enter image description here

4. Set up your system to detect your device.
Follow the instructions below for your OS:


Windows Users

Install the Google USB Driver from the ADT SDK Manager
(Support for: ADP1, ADP2, Verizon Droid, Nexus One, Nexus S).

enter image description here

For devices not listed above, install an OEM driver for your device


Mac OS X

Your device should automatically work; Go to the next step


Ubuntu Linux

Add a udev rules file that contains a USB configuration for each type of device you want to use for development. In the rules file, each device manufacturer is identified by a unique vendor ID, as specified by the ATTR{idVendor} property. For a list of vendor IDs, click here. To set up device detection on Ubuntu Linux:

  1. Log in as root and create this file: /etc/udev/rules.d/51-android.rules.
  2. Use this format to add each vendor to the file:
    SUBSYSTEM=="usb", ATTR{idVendor}=="0bb4", MODE="0666", GROUP="plugdev"
    In this example, the vendor ID is for HTC. The MODE assignment specifies read/write permissions, and GROUP defines which Unix group owns the device node.
  3. Now execute: chmod a+r /etc/udev/rules.d/51-android.rules

Note: The rule syntax may vary slightly depending on your environment. Consult the udev documentation for your system as needed. For an overview of rule syntax, see this guide to writing udev rules.


5. Run the project with your connected device.

With Eclipse/ADT: run or debug your application as usual. You will be presented with a Device Chooser dialog that lists the available emulator(s) and connected device(s).

With ADB: issue commands with the -d flag to target your connected device.

Still need help? Click here for the full guide.

What's the purpose of git-mv?

Maybe git mv has changed since these answers were posted, so I will update briefly. In my view, git mv is not accurately described as short hand for:

 # not accurate: #
 mv oldname newname
 git add newname
 git rm oldname

I use git mv frequently for two reasons that have not been described in previous answers:

  1. Moving large directory structures, where I have mixed content of both tracked and untracked files. Both tracked and untracked files will move, and retain their tracking/untracking status

  2. Moving files and directories that are large, I have always assumed that git mv will reduce the size of the repository DB history size. This is because moving/renaming a file is indexation/reference delta. I have not verified this assumption, but it seems logical.

Missing include "bits/c++config.h" when cross compiling 64 bit program on 32 bit in Ubuntu

Adding this answer partially because it fixed my problem of the same issue and so I can bookmark this question myself.

I was able to fix it by doing the following:

sudo apt-get install gcc-multilib g++-multilib

If you've installed a version of gcc / g++ that doesn't ship by default (such as g++-4.8 on lucid) you'll want to match the version as well:

sudo apt-get install gcc-4.8-multilib g++-4.8-multilib

Get names of all keys in the collection

As per the mongoldb documentation, a combination of distinct

Finds the distinct values for a specified field across a single collection or view and returns the results in an array.

and indexes collection operations are what would return all possible values for a given key, or index:

Returns an array that holds a list of documents that identify and describe the existing indexes on the collection

So in a given method one could do use a method like the following one, in order to query a collection for all it's registered indexes, and return, say an object with the indexes for keys (this example uses async/await for NodeJS, but obviously you could use any other asynchronous approach):

async function GetFor(collection, index) {

    let currentIndexes;
    let indexNames = [];
    let final = {};
    let vals = [];

    try {
        currentIndexes = await collection.indexes();
        await ParseIndexes();
        //Check if a specific index was queried, otherwise, iterate for all existing indexes
        if (index && typeof index === "string") return await ParseFor(index, indexNames);
        await ParseDoc(indexNames);
        await Promise.all(vals);
        return final;
    } catch (e) {
        throw e;
    }

    function ParseIndexes() {
        return new Promise(function (result) {
            let err;
            for (let ind in currentIndexes) {
                let index = currentIndexes[ind];
                if (!index) {
                    err = "No Key For Index "+index; break;
                }
                let Name = Object.keys(index.key);
                if (Name.length === 0) {
                    err = "No Name For Index"; break;
                }
                indexNames.push(Name[0]);
            }
            return result(err ? Promise.reject(err) : Promise.resolve());
        })
    }

    async function ParseFor(index, inDoc) {
        if (inDoc.indexOf(index) === -1) throw "No Such Index In Collection";
        try {
            await DistinctFor(index);
            return final;
        } catch (e) {
            throw e
        }
    }
    function ParseDoc(doc) {
        return new Promise(function (result) {
            let err;
            for (let index in doc) {
                let key = doc[index];
                if (!key) {
                    err = "No Key For Index "+index; break;
                }
                vals.push(new Promise(function (pushed) {
                    DistinctFor(key)
                        .then(pushed)
                        .catch(function (err) {
                            return pushed(Promise.resolve());
                        })
                }))
            }
            return result(err ? Promise.reject(err) : Promise.resolve());
        })
    }

    async function DistinctFor(key) {
        if (!key) throw "Key Is Undefined";
        try {
            final[key] = await collection.distinct(key);
        } catch (e) {
            final[key] = 'failed';
            throw e;
        }
    }
}

So querying a collection with the basic _id index, would return the following (test collection only has one document at the time of the test):

Mongo.MongoClient.connect(url, function (err, client) {
    assert.equal(null, err);

    let collection = client.db('my db').collection('the targeted collection');

    GetFor(collection, '_id')
        .then(function () {
            //returns
            // { _id: [ 5ae901e77e322342de1fb701 ] }
        })
        .catch(function (err) {
            //manage your error..
        })
});

Mind you, this uses methods native to the NodeJS Driver. As some other answers have suggested, there are other approaches, such as the aggregate framework. I personally find this approach more flexible, as you can easily create and fine-tune how to return the results. Obviously, this only addresses top-level attributes, not nested ones. Also, to guarantee that all documents are represented should there be secondary indexes (other than the main _id one), those indexes should be set as required.

How to find minimum value from vector?

template <class ForwardIterator>
ForwardIterator min_element ( ForwardIterator first, ForwardIterator last )
{
    ForwardIterator lowest = first;
    if (first == last) return last;
    while (++first != last)
    if (*first < *lowest) 
        lowest = first;
    return lowest;
}

Output grep results to text file, need cleaner output

grep -n "YOUR SEARCH STRING" * > output-file

The -n will print the line number and the > will redirect grep-results to the output-file.
If you want to "clean" the results you can filter them using pipe | for example:
grep -n "test" * | grep -v "mytest" > output-file will match all the lines that have the string "test" except the lines that match the string "mytest" (that's the switch -v) - and will redirect the result to an output file.
A few good grep-tips can be found on this post

How to show google.com in an iframe?

As it has been outlined here, because Google is sending an "X-Frame-Options: SAMEORIGIN" response header you cannot simply set the src to "http://www.google.com" in a iframe.

If you want to embed Google into an iframe you can do what sudopeople suggested in a comment above and use a Google custom search link like the following. This worked great for me (left 'q=' blank to start with blank search).

<iframe id="if1" width="100%" height="254" style="visibility:visible" src="http://www.google.com/custom?q=&btnG=Search"></iframe>

EDIT:

This answer no longer works. For information, and instructions on how to replace an iframe search with a google custom search element check out: https://support.google.com/customsearch/answer/2641279

jquery <a> tag click event

That's because your hidden fields have duplicate IDs, so jQuery only returns the first in the set. Give them classes instead, like .uid and grab them via:

var uids = $(".uid").map(function() {
    return this.value;
}).get();

Demo: http://jsfiddle.net/karim79/FtcnJ/

EDIT: say your output looks like the following (notice, IDs have changed to classes)

<fieldset><legend>John Smith</legend>
<img src='foo.jpg'/><br>
<a href="#" class="aaf">add as friend</a>
<input name="uid" type="hidden" value='<?php echo $row->uid;?>' class="uid">
</fieldset>

You can target the 'uid' relative to the clicked anchor like this:

$("a.aaf").click(function() {
    alert($(this).next('.uid').val());
});

Important: do not have any duplicate IDs. They will cause problems. They are invalid, bad and you should not do it.

Set a Fixed div to 100% width of the parent container

Try adding a transform to the parent (doesn't have to do anything, could be a zero translation) and set the fixed child's width to 100%

_x000D_
_x000D_
body{ height:20000px }_x000D_
#wrapper {padding:10%;}_x000D_
#wrap{ _x000D_
    float: left;_x000D_
    position: relative;_x000D_
    width: 40%; _x000D_
    background:#ccc; _x000D_
    transform: translate(0, 0);_x000D_
}_x000D_
#fixed{ _x000D_
    position:fixed;_x000D_
    width:100%;_x000D_
    padding:0px;_x000D_
    height:10px;_x000D_
    background-color:#333;_x000D_
}
_x000D_
<div id="wrapper">_x000D_
    <div id="wrap">_x000D_
    Some relative item placed item_x000D_
    <div id="fixed"></div>_x000D_
    </div>_x000D_
</div>
_x000D_
_x000D_
_x000D_

PostgreSQL: days/months/years between two dates

I spent some time looking for the best answer, and I think I have it.

This sql will give you the number of days between two dates as integer:

SELECT
    (EXTRACT(epoch from age('2017-6-15', now())) / 86400)::int

..which, when run today (2017-3-28), provides me with:

?column?
------------
77

The misconception about the accepted answer:

select age('2010-04-01', '2012-03-05'),
   date_part('year',age('2010-04-01', '2012-03-05')),
   date_part('month',age('2010-04-01', '2012-03-05')),
   date_part('day',age('2010-04-01', '2012-03-05'));

..is that you will get the literal difference between the parts of the date strings, not the amount of time between the two dates.

I.E:

Age(interval)=-1 years -11 mons -4 days;

Years(double precision)=-1;

Months(double precision)=-11;

Days(double precision)=-4;

Cannot find Dumpbin.exe

As for VS2017, I found it under C:\Program Files (x86)\Microsoft Visual Studio\2017\Community\VC\Tools\MSVC\14.14.26428\bin\Hostx64\x64

nvarchar(max) still being truncated

Your first problem is a limitation of the PRINT statement. I'm not sure why sp_executesql is failing. It should support pretty much any length of input.

Perhaps the reason the query is malformed is something other than truncation.

Remove the newline character in a list read from a file

Here are various optimisations and applications of proper Python style to make your code a lot neater. I've put in some optional code using the csv module, which is more desirable than parsing it manually. I've also put in a bit of namedtuple goodness, but I don't use the attributes that then provides. Names of the parts of the namedtuple are inaccurate, you'll need to correct them.

import csv
from collections import namedtuple
from time import localtime, strftime

# Method one, reading the file into lists manually (less desirable)
with open('grades.dat') as files:
    grades = [[e.strip() for e in s.split(',')] for s in files]

# Method two, using csv and namedtuple
StudentRecord = namedtuple('StudentRecord', 'id, lastname, firstname, something, homework1, homework2, homework3, homework4, homework5, homework6, homework7, exam1, exam2, exam3')
grades = map(StudentRecord._make, csv.reader(open('grades.dat')))
# Now you could have student.id, student.lastname, etc.
# Skipping the namedtuple, you could do grades = map(tuple, csv.reader(open('grades.dat')))

request = open('requests.dat', 'w')
cont = 'y'

while cont.lower() == 'y':
    answer = raw_input('Please enter the Student I.D. of whom you are looking: ')
    for student in grades:
        if answer == student[0]:
            print '%s, %s      %s      %s' % (student[1], student[2], student[0], student[3])
            time = strftime('%a, %b %d %Y %H:%M:%S', localtime())
            print time
            print 'Exams - %s, %s, %s' % student[11:14]
            print 'Homework - %s, %s, %s, %s, %s, %s, %s' % student[4:11]
            total = sum(int(x) for x in student[4:14])
            print 'Total points earned - %d' % total
            grade = total / 5.5
            if grade >= 90:
                letter = 'an A'
            elif grade >= 80:
                letter = 'a B'
            elif grade >= 70:
                letter = 'a C'
            elif grade >= 60:
                letter = 'a D'
            else:
                letter = 'an F'

            if letter = 'an A':
                print 'Grade: %s, that is equal to %s.' % (grade, letter)
            else:
                print 'Grade: %.2f, that is equal to %s.' % (grade, letter)

            request.write('%s %s, %s %s\n' % (student[0], student[1], student[2], time))


    print
    cont = raw_input('Would you like to search again? ')

print 'Goodbye.'

How to convert a string with Unicode encoding to a string of letters

You can use StringEscapeUtils from Apache Commons Lang, i.e.:

String Title = StringEscapeUtils.unescapeJava("\\u0048\\u0065\\u006C\\u006C\\u006F");

How to "flatten" a multi-dimensional array to simple one in PHP?

Another method from PHP's user comments (simplified) and here:

function array_flatten_recursive($array) { 
   if (!$array) return false;
   $flat = array();
   $RII = new RecursiveIteratorIterator(new RecursiveArrayIterator($array));
   foreach ($RII as $value) $flat[] = $value;
   return $flat;
}

The big benefit of this method is that it tracks the depth of the recursion, should you need that while flattening.
This will output:

$array = array( 
    'A' => array('B' => array( 1, 2, 3)), 
    'C' => array(4, 5) 
); 
print_r(array_flatten_recursive($array)); 

#Returns: 
Array ( 
    [0] => 1 
    [1] => 2 
    [2] => 3 
    [3] => 4 
    [4] => 5 
)

Why can I not push_back a unique_ptr into a vector?

You need to move the unique_ptr:

vec.push_back(std::move(ptr2x));

unique_ptr guarantees that a single unique_ptr container has ownership of the held pointer. This means that you can't make copies of a unique_ptr (because then two unique_ptrs would have ownership), so you can only move it.

Note, however, that your current use of unique_ptr is incorrect. You cannot use it to manage a pointer to a local variable. The lifetime of a local variable is managed automatically: local variables are destroyed when the block ends (e.g., when the function returns, in this case). You need to dynamically allocate the object:

std::unique_ptr<int> ptr(new int(1));

In C++14 we have an even better way to do so:

make_unique<int>(5);

How do I convert csv file to rdd

I think you can try to load that csv into a RDD and then create a dataframe from that RDD, here is the document of creating dataframe from rdd:http://spark.apache.org/docs/latest/sql-programming-guide.html#interoperating-with-rdds

Run PHP function on html button click

A php file is run whenever you access it via an HTTP request be it GET,POST, PUT.

You can use JQuery/Ajax to send a request on a button click, or even just change the URL of the browser to navigate to the php address.

Depending on the data sent in the POST/GET you can have a switch statement running a different function.

Specifying Function via GET

You can utilize the code here: How to call PHP function from string stored in a Variable along with a switch statement to automatically call the appropriate function depending on data sent.

So on PHP side you can have something like this:

<?php

//see http://php.net/manual/en/function.call-user-func-array.php how to use extensively
if(isset($_GET['runFunction']) && function_exists($_GET['runFunction']))
call_user_func($_GET['runFunction']);
else
echo "Function not found or wrong input";

function test()
{
echo("test");
}

function hello()
{
echo("hello");
}

?>

and you can make the simplest get request using the address bar as testing:

http://127.0.0.1/test.php?runFunction=hellodddddd

results in:

Function not found or wrong input

http://127.0.0.1/test.php?runFunction=hello

results in:

hello

Sending the Data

GET Request via JQuery

See: http://api.jquery.com/jQuery.get/

$.get("test.cgi", { name: "John"})
.done(function(data) {
  alert("Data Loaded: " + data);
});

POST Request via JQuery

See: http://api.jquery.com/jQuery.post/

$.post("test.php", { name: "John"} );

GET Request via Javascript location

See: http://www.javascripter.net/faq/buttonli.htm

<input type=button 
value="insert button text here"
onClick="self.location='Your_URL_here.php?name=hello'">

Reading the Data (PHP)

See PHP Turotial for reading post and get: http://www.tizag.com/phpT/postget.php

Useful Links

http://php.net/manual/en/function.call-user-func.php http://php.net/manual/en/function.function-exists.php

Remove xticks in a matplotlib plot?

There is a better, and simpler, solution than the one given by John Vinyard. Use NullLocator:

import matplotlib.pyplot as plt

plt.plot(range(10))
plt.gca().xaxis.set_major_locator(plt.NullLocator())
plt.show()
plt.savefig('plot')

Hope that helps.

SQL Server default character encoding

SELECT DATABASEPROPERTYEX('DBName', 'Collation') SQLCollation;

Where DBName is your database name.

Creating a script for a Telnet session?

Bash shell supports this out-of-box, e.g.

exec {stream}<>/dev/tcp/example.com/80
printf "GET / HTTP/1.1\nHost: example.com\nConnection: close\n\n" >&${stream}
cat <&${stream}

To filter and only show some lines, run: grep Example <&${stream}.

Print multiple arguments in Python

In Python 3.6, f-string is much cleaner.

In earlier version:

print("Total score for %s is %s. " % (name, score))

In Python 3.6:

print(f'Total score for {name} is {score}.')

will do.

It is more efficient and elegant.

Why is using onClick() in HTML a bad practice?

It's not good for several reasons:

  • it mixes code and markup
  • code written this way goes through eval
  • and runs in the global scope

The simplest thing would be to add a name attribute to your <a> element, then you could do:

document.myelement.onclick = function() {
    window.popup('/map/', 300, 300, 'map');
    return false;
};

although modern best practise would be to use an id instead of a name, and use addEventListener() instead of using onclick since that allows you to bind multiple functions to a single event.

Windows 7 - 'make' is not recognized as an internal or external command, operable program or batch file

  1. First make sure you have MinGW installed.
  2. From MinGW installation manager check if you have the mingw32-make package installed.
  3. Check if you have added the MinGW bin folder to your PATH. type PATH in your command line and look for the folder. Or on windows 10 go to Control Panel\System and Security\System --> Advanced system settings --> Environment Variables --> System Variables find Path variable, select, Edit and check if it is there. If not just add it!
  4. As explained here, create a new file in any of your PATH folders. For example create mingwstartup.bat in the MinGW bin folder. write the line doskey make=mingw32-make.exe inside, save and close it.
  5. open Registry Editor by running regedit. As explained here in HKEY_LOCAL_MACHINE or HKEY_CURRENT_USER go to \Software\Microsoft\Command Processor right click on the right panel New --> Expandable String Value and name it AutoRun. double click and enter the path to your .bat file as the Value data (e.g. "C:\MinGW\bin\mingwstartup.bat") the result should look like this:

enter image description here

now every time you open a new terminal make command will run the mingw32-make.exe. I hope it helps.

P.S. If you don't want to see the commands of the .bat file to be printed out to the terminal put @echo off at the top of the batch file.

How to set Google Chrome in WebDriver

For Mac -Chrome browser

public class MultipleBrowser {

    public WebDriver driver= null;
    String browser="mozilla";
    String url="https://www.omnicard.com";

    @BeforeMethod
    public void LaunchBrowser() {

      if(browser.equalsIgnoreCase("mozilla"))
          driver= new FirefoxDriver();
      else if(browser.equalsIgnoreCase("safari"))
          driver= new SafariDriver();
      else if(browser.equalsIgnoreCase("chrome"))
          System.setProperty("webdriver.chrome.driver","/Users/mhossain/Desktop/chromedriver");
          driver= new ChromeDriver();   
          driver.manage().timeouts().implicitlyWait(4, TimeUnit.SECONDS);
          driver.navigate().to(url);
          //driver.manage().deleteAllCookies();

  }

Use child_process.execSync but keep output in console

You can simply use .toString().

var result = require('child_process').execSync('rsync -avAXz --info=progress2 "/src" "/dest"').toString();
console.log(result);

This has been tested on Node v8.5.0, I'm not sure about previous versions. According to @etov, it doesn't work on v6.3.1 - I'm not sure about in-between.


Edit: Looking back on this, I've realised that it doesn't actually answer the specific question because it doesn't show the output to you 'live' — only once the command has finished running.

However, I'm leaving this answer here because I know quite a few people come across this question just looking for how to print the result of the command after execution.

java.lang.IllegalStateException: The specified child already has a parent

This solution can help :

public class FragmentItem extends Android.Support.V4.App.Fragment
{
    View rootView;
    TextView textView;

    public override View OnCreateView(LayoutInflater inflater, ViewGroup container, Bundle savedInstanceState) {
        if (rootView != null) 
        {
            ViewGroup parent = (ViewGroup)rootView.Parent;
            parent.RemoveView(rootView);
        } else {
            rootView = inflater.Inflate(Resource.Layout.FragmentItem, container, false);
            textView = rootView.FindViewById<TextView>(Resource.Id.textViewDisplay);            
        }
        return rootView;
    }
}

How to disable registration new users in Laravel

I had to use:

public function getRegister()
{
    return redirect('/');
}

Using Redirect::to() gave me an error:

Class 'App\Http\Controllers\Auth\Redirect' not found

JSON for List of int

JSON is perfectly capable of expressing lists of integers, and the JSON you have posted is valid. You can simply separate the integers by commas:

{
    "Id": "610",
    "Name": "15",
    "Description": "1.99",
    "ItemModList": [42, 47, 139]
}

How to convert hex to rgb using Java?

For shortened hex code like #fff or #000

int red = "colorString".charAt(1) == '0' ? 0 : 
     "colorString".charAt(1) == 'f' ? 255 : 228;  
int green =
     "colorString".charAt(2) == '0' ? 0 :  "colorString".charAt(2) == 'f' ?
     255 : 228;  
int blue = "colorString".charAt(3) == '0' ? 0 : 
     "colorString".charAt(3) == 'f' ? 255 : 228;

Color.rgb(red, green,blue);

Twitter Bootstrap Responsive Background-Image inside Div

Mby bootstrap img-responsive class is you looking for.

Making a WinForms TextBox behave like your browser's address bar

I found a simpler solution to this. It involves kicking off the SelectAll asynchronously using Control.BeginInvoke so that it occurs after the Enter and Click events have occurred:

In C#:

private void MyTextBox_Enter(object sender, EventArgs e)
{
    // Kick off SelectAll asyncronously so that it occurs after Click
    BeginInvoke((Action)delegate
    {
        MyTextBox.SelectAll();
    });
}

In VB.NET (thanks to Krishanu Dey)

Private Sub MyTextBox_Enter(sender As Object, e As EventArgs) Handles MyTextBox.Enter 
    BeginInvoke(DirectCast(Sub() MyTextBox.SelectAll(), Action)) 
End Sub

HTML CSS Button Positioning

as I expected, yeah, it's because the whole DOM element is being pushed down. You have multiple options. You can put the buttons in separate divs, and float them so that they don't affect each other. the simpler solution is to just set the :active button to position:relative; and use top instead of margin or line-height. example fiddle: http://jsfiddle.net/5CZRP/

Failed to authenticate on SMTP server error using gmail

I had the same issue, but when I ran the following command, it was ok:

php artisan config:cache

JAVA_HOME should point to a JDK not a JRE

Be sure to use the correct path!

I mistakenly had written C:\Program Files\Java\. Changing it to C:\Program Files\Java\jdk\11.0.6\ fixed the issue.

In cmd I then checked for the version of maven with mvn -version.

How to find length of a string array?

This won't work. You first have to initialize the array. So far, you only have a String[] reference, pointing to null.

When you try to read the length member, what you actually do is null.length, which results in a NullPointerException.

Resolve promises one after another (i.e. in sequence)?

Here is how I prefer to run tasks in series.

function runSerial() {
    var that = this;
    // task1 is a function that returns a promise (and immediately starts executing)
    // task2 is a function that returns a promise (and immediately starts executing)
    return Promise.resolve()
        .then(function() {
            return that.task1();
        })
        .then(function() {
            return that.task2();
        })
        .then(function() {
            console.log(" ---- done ----");
        });
}

What about cases with more tasks? Like, 10?

function runSerial(tasks) {
  var result = Promise.resolve();
  tasks.forEach(task => {
    result = result.then(() => task());
  });
  return result;
}

Why doesn't importing java.util.* include Arrays and Lists?

Take a look at this forum http://htmlcoderhelper.com/why-is-using-a-wild-card-with-a-java-import-statement-bad/. Theres a discussion on how using wildcards can lead to conflicts if you add new classes to the packages and if there are two classes with the same name in different packages where only one of them will be imported.

Update


It gives that warning because your the line should actually be

List<Integer> i = new ArrayList<Integer>(Arrays.asList(0,1,2,3,4,5,6,7,8,9,10));
List<Integer> j = new ArrayList<Integer>();

You need to specify the type for array list or the compiler will give that warning because it cannot identify that you are using the list in a type safe way.

How to set "value" to input web element using selenium?

As Shubham Jain stated, this is working to me: driver.findElement(By.id("invoice_supplier_id")).sendKeys("value"??, "new value");

make a phone call click on a button

Have you given the permission in the manifest file

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

and inside your activity

  Intent callIntent = new Intent(Intent.ACTION_CALL);
    callIntent.setData(Uri.parse("tel:123456789"));
    startActivity(callIntent);

Let me know if you find any issue.

What does OpenCV's cvWaitKey( ) function do?

cvWaitKey(x) / cv::waitKey(x) does two things:

  1. It waits for x milliseconds for a key press on a OpenCV window (i.e. created from cv::imshow()). Note that it does not listen on stdin for console input. If a key was pressed during that time, it returns the key's ASCII code. Otherwise, it returns -1. (If x is zero, it waits indefinitely for the key press.)
  2. It handles any windowing events, such as creating windows with cv::namedWindow(), or showing images with cv::imshow().

A common mistake for opencv newcomers is to call cv::imshow() in a loop through video frames, without following up each draw with cv::waitKey(30). In this case, nothing appears on screen, because highgui is never given time to process the draw requests from cv::imshow().

How to apply CSS to iframe?

There is a wonderful script that replaces a node with an iframe version of itself. CodePen Demo

enter image description here

Usage Examples:

// Single node
var component = document.querySelector('.component');
var iframe = iframify(component);

// Collection of nodes
var components = document.querySelectorAll('.component');
var iframes = Array.prototype.map.call(components, function (component) {
  return iframify(component, {});
});

// With options
var component = document.querySelector('.component');
var iframe = iframify(component, {
  headExtra: '<style>.component { color: red; }</style>',
  metaViewport: '<meta name="viewport" content="width=device-width">'
});

Vue.JS: How to call function after page loaded?

// vue js provides us `mounted()`. this means `onload` in javascript.

mounted () {
  // we can implement any method here like
   sampleFun () {
      // this is the sample method you can implement whatever you want
   }
}

Heap vs Binary Search Tree (BST)

As mentioned by others, Heap can do findMin or findMax in O(1) but not both in the same data structure. However I disagree that Heap is better in findMin/findMax. In fact, with a slight modification, the BST can do both findMin and findMax in O(1).

In this modified BST, you keep track of the the min node and max node everytime you do an operation that can potentially modify the data structure. For example in insert operation you can check if the min value is larger than the newly inserted value, then assign the min value to the newly added node. The same technique can be applied on the max value. Hence, this BST contain these information which you can retrieve them in O(1). (same as binary heap)

In this BST (Balanced BST), when you pop min or pop max, the next min value to be assigned is the successor of the min node, whereas the next max value to be assigned is the predecessor of the max node. Thus it perform in O(1). However we need to re-balance the tree, thus it will still run O(log n). (same as binary heap)

I would be interested to hear your thought in the comment below. Thanks :)

Update

Cross reference to similar question Can we use binary search tree to simulate heap operation? for more discussion on simulating Heap using BST.

What to use now Google News API is deprecated?

Depending on your needs, you want to use their section feeds, their search feeds

http://news.google.com/news?q=apple&output=rss

or Bing News Search.

http://www.bing.com/toolbox/bingdeveloper/

How to properly add include directories with CMake

CMake is more like a script language if comparing it with other ways to create Makefile (e.g. make or qmake). It is not very cool like Python, but still.

There are no such thing like a "proper way" if looking in various opensource projects how people include directories. But there are two ways to do it.

  1. Crude include_directories will append a directory to the current project and all other descendant projects which you will append via a series of add_subdirectory commands. Sometimes people say that such approach is legacy.

  2. A more elegant way is with target_include_directories. It allows to append a directory for a specific project/target without (maybe) unnecessary inheritance or clashing of various include directories. Also allow to perform even a subtle configuration and append one of the following markers for this command.

PRIVATE - use only for this specified build target

PUBLIC - use it for specified target and for targets which links with this project

INTERFACE -- use it only for targets which links with the current project

PS:

  1. Both commands allow to mark a directory as SYSTEM to give a hint that it is not your business that specified directories will contain warnings.

  2. A similar answer is with other pairs of commands target_compile_definitions/add_definitions, target_compile_options/CMAKE_C_FLAGS

How to prevent the "Confirm Form Resubmission" dialog?

It seems you are looking for the Post/Redirect/Get pattern.

As another solution you may stop to use redirecting at all.

You may process and render the processing result at once with no POST confirmation alert. You should just manipulate the browser history object:

history.replaceState("", "", "/the/result/page")

See full or short answers

Twitter Bootstrap: Print content of modal window

With the currently accepted solution you cannot print the page which contains the dialog itself anymore. Here's a much more dynamic solution:

JavaScript:

$().ready(function () {
    $('.modal.printable').on('shown.bs.modal', function () {
        $('.modal-dialog', this).addClass('focused');
        $('body').addClass('modalprinter');

        if ($(this).hasClass('autoprint')) {
            window.print();
        }
    }).on('hidden.bs.modal', function () {
        $('.modal-dialog', this).removeClass('focused');
        $('body').removeClass('modalprinter');
    });
});

CSS:

@media print {
    body.modalprinter * {
        visibility: hidden;
    }

    body.modalprinter .modal-dialog.focused {
        position: absolute;
        padding: 0;
        margin: 0;
        left: 0;
        top: 0;
    }

    body.modalprinter .modal-dialog.focused .modal-content {
        border-width: 0;
    }

    body.modalprinter .modal-dialog.focused .modal-content .modal-header .modal-title,
    body.modalprinter .modal-dialog.focused .modal-content .modal-body,
    body.modalprinter .modal-dialog.focused .modal-content .modal-body * {
        visibility: visible;
    }

    body.modalprinter .modal-dialog.focused .modal-content .modal-header,
    body.modalprinter .modal-dialog.focused .modal-content .modal-body {
        padding: 0;
    }

    body.modalprinter .modal-dialog.focused .modal-content .modal-header .modal-title {
        margin-bottom: 20px;
    }
}

Example:

<div class="modal fade printable autoprint">
  <div class="modal-dialog">
    <div class="modal-content">
      <div class="modal-header">
        <button type="button" class="close" data-dismiss="modal" aria-hidden="true">&times;</button>
        <h4 class="modal-title">Modal title</h4>
      </div>
      <div class="modal-body">
        <p>One fine body&hellip;</p>
      </div>
      <div class="modal-footer">
        <button type="button" class="btn btn-default" data-dismiss="modal">Close</button>
        <button type="button" class="btn btn-primary" onclick="window.print();">Print</button>
      </div>
    </div><!-- /.modal-content -->
  </div><!-- /.modal-dialog -->
</div><!-- /.modal -->

Why is my asynchronous function returning Promise { <pending> } instead of a value?

The promise will always log pending as long as its results are not resolved yet. You must call .then on the promise to capture the results regardless of the promise state (resolved or still pending):

let AuthUser = function(data) {
  return google.login(data.username, data.password).then(token => { return token } )
}

let userToken = AuthUser(data)
console.log(userToken) // Promise { <pending> }

userToken.then(function(result) {
   console.log(result) // "Some User token"
})

Why is that?

Promises are forward direction only; You can only resolve them once. The resolved value of a Promise is passed to its .then or .catch methods.

Details

According to the Promises/A+ spec:

The promise resolution procedure is an abstract operation taking as input a promise and a value, which we denote as [[Resolve]](promise, x). If x is a thenable, it attempts to make promise adopt the state of x, under the assumption that x behaves at least somewhat like a promise. Otherwise, it fulfills promise with the value x.

This treatment of thenables allows promise implementations to interoperate, as long as they expose a Promises/A+-compliant then method. It also allows Promises/A+ implementations to “assimilate” nonconformant implementations with reasonable then methods.

This spec is a little hard to parse, so let's break it down. The rule is:

If the function in the .then handler returns a value, then the Promise resolves with that value. If the handler returns another Promise, then the original Promise resolves with the resolved value of the chained Promise. The next .then handler will always contain the resolved value of the chained promise returned in the preceding .then.

The way it actually works is described below in more detail:

1. The return of the .then function will be the resolved value of the promise.

function initPromise() {
  return new Promise(function(res, rej) {
    res("initResolve");
  })
}

initPromise()
  .then(function(result) {
    console.log(result); // "initResolve"
    return "normalReturn";
  })
  .then(function(result) {
    console.log(result); // "normalReturn"
  });

2. If the .then function returns a Promise, then the resolved value of that chained promise is passed to the following .then.

function initPromise() {
  return new Promise(function(res, rej) {
    res("initResolve");
  })
}

initPromise()
  .then(function(result) {
    console.log(result); // "initResolve"
    return new Promise(function(resolve, reject) {
       setTimeout(function() {
          resolve("secondPromise");
       }, 1000)
    })
  })
  .then(function(result) {
    console.log(result); // "secondPromise"
  });

How to beautify JSON in Python?

You could pipe the output to jq. If you python script contains something like

print json.dumps(data)

then you can fire:

python foo.py | jq '.'

Using sudo with Python script

I used this for python 3.5. I did it using subprocess module.Using the password like this is very insecure.

The subprocess module takes command as a list of strings so either create a list beforehand using split() or pass the whole list later. Read the documentation for moreinformation.

#!/usr/bin/env python
import subprocess

sudoPassword = 'mypass'
command = 'mount -t vboxsf myfolder /home/myuser/myfolder'.split()

cmd1 = subprocess.Popen(['echo',sudoPassword], stdout=subprocess.PIPE)
cmd2 = subprocess.Popen(['sudo','-S'] + command, stdin=cmd1.stdout, stdout=subprocess.PIPE)

output = cmd2.stdout.read.decode()

How to tell if UIViewController's view is visible

For my purposes, in the context of a container view controller, I've found that

- (BOOL)isVisible {
    return (self.isViewLoaded && self.view.window && self.parentViewController != nil);
}

works well.

Closing Excel Application Process in C# after Data Access

You may kill process with your own COM object excel pid

add somewhere below dll import code

[DllImport("user32.dll", SetLastError = true)]
private static extern int GetWindowThreadProcessId(IntPtr hwnd, ref int lpdwProcessId);

and use

 if (excelApp != null)
            {
                int excelProcessId = -1;
                GetWindowThreadProcessId(new IntPtr(excelApp.Hwnd), ref excelProcessId);

                Process ExcelProc = Process.GetProcessById(excelProcessId);
                if (ExcelProc != null)
                {
                    ExcelProc.Kill();
                }
            }

How to use ADB to send touch events to device using sendevent command?

Building on top of Tomas's answer, this is the best approach of finding the location tap position as an integer I found:

adb shell getevent -l | grep ABS_MT_POSITION --line-buffered | awk '{a = substr($0,54,8); sub(/^0+/, "", a); b = sprintf("0x%s",a); printf("%d\n",strtonum(b))}'

Use adb shell getevent -l to get a list of events, the using grep for ABS_MT_POSITION (gets the line with touch events in hex) and finally use awk to get the relevant hex values, strip them of zeros and convert hex to integer. This continuously prints the x and y coordinates in the terminal only when you press on the device.

You can then use this adb shell command to send the command:

adb shell input tap x y

How to pass dictionary items as function arguments in python?

*data interprets arguments as tuples, instead you have to pass **data which interprets the arguments as dictionary.

data = {'school':'DAV', 'class': '7', 'name': 'abc', 'city': 'pune'}


def my_function(**data):
    schoolname  = data['school']
    cityname = data['city']
    standard = data['class']
    studentname = data['name']

You can call the function like this:

my_function(**data)

How can I programmatically determine if my app is running in the iphone simulator?

The previous answers are a little dated. I found that all you need to do is query the TARGET_IPHONE_SIMULATOR macro (no need to include any other header files [assuming you are coding for iOS]).

I attempted TARGET_OS_IPHONE but it returned the same value (1) when running on an actual device and simulator, that's why I recommend using TARGET_IPHONE_SIMULATOR instead.

How to create a new img tag with JQuery, with the src and id from a JavaScript object?

var img = $('<img />', { 
  id: 'Myid',
  src: 'MySrc.gif',
  alt: 'MyAlt'
});
img.appendTo($('#YourDiv'));

Android difference between Two Dates

When you use Date() to calculate the difference in hours is necessary configure the SimpleDateFormat() in UTC otherwise you get one hour error due to Daylight SavingTime.

Create Directory When Writing To File In Node.js

If you don't want to use any additional package, you can call the following function before creating your file:

var path = require('path'),
    fs = require('fs');

function ensureDirectoryExistence(filePath) {
  var dirname = path.dirname(filePath);
  if (fs.existsSync(dirname)) {
    return true;
  }
  ensureDirectoryExistence(dirname);
  fs.mkdirSync(dirname);
}

Test if a property is available on a dynamic variable

In my case, I needed to check for the existence of a method with a specific name, so I used an interface for that

var plugin = this.pluginFinder.GetPluginIfInstalled<IPlugin>(pluginName) as dynamic;
if (plugin != null && plugin is ICustomPluginAction)
{
    plugin.CustomPluginAction(action);
}

Also, interfaces can contain more than just methods:

Interfaces can contain methods, properties, events, indexers, or any combination of those four member types.

From: Interfaces (C# Programming Guide)

Elegant and no need to trap exceptions or play with reflexion...

How to catch a click event on a button?

/src/com/example/MyClass.java

package com.example

import android.app.Activity;
import android.os.Bundle;
import android.view.View;
import android.view.View.OnClickListener;
import android.widget.Button;
import android.widget.ImageView;

public class MyClass extends Activity
{

  @Override
  public void onCreate(Bundle savedInstanceState)
  {
    super.onCreate(savedInstanceState);
    setContentView(R.layout.main);    

    Button button = (Button) findViewById(R.id.button1);

    button.setOnClickListener(new OnClickListener()
    {
      public void onClick(View v)
      {
         ImageView iv = (ImageView) findViewById(R.id.imageview1);
         iv.setVisibility(View.VISIBLE);
      }
    });

  }
}

/res/layout/main.xml

<?xml version="1.0" encoding="utf-8"?>
<LinearLayout
  xmlns:android="http://schemas.android.com/apk/res/android"
  android:layout_width="fill_parent"
  android:layout_height="fill_parent">
    <Button 
      android:text="Button"
      android:id="@+id/button1"
      android:layout_width="wrap_content" 
      android:layout_height="wrap_content"
    />
    <ImageView 
      android:src="@drawable/image" 
      android:layout_height="wrap_content" 
      android:layout_width="wrap_content" 
      android:id="@+id/imageview1"
      android:visibility="invisible"
    />
</LinearLayout>

Setting up maven dependency for SQL Server

Download the driver JAR from the link provided by Olaf and add it to your local Maven repository with;

mvn install:install-file -Dfile=sqljdbc4.jar -DgroupId=com.microsoft.sqlserver -DartifactId=sqljdbc4 -Dversion=4.0 -Dpackaging=jar

Then add it to your project with;

<dependency>
  <groupId>com.microsoft.sqlserver</groupId>
  <artifactId>sqljdbc4</artifactId>
  <version>4.0</version>
</dependency>

how to call a method in another Activity from Activity

Declare a SecondActivity variable in FirstActivity

Like this

public class FirstActivity extends Activity {  

SecondActivity secactivity;

public void onCreate(Bundle savedInstanceState) {
    super.onCreate(savedInstanceState);
    setContentView(R.layout.main2);
  }      

  public void method() {
    // some code

  secactivity.call_method();// 'Method' is Name of the any one method in SecondActivity

  }  
}  

Using this format you can call any method from one activity to another.

Splitting a Java String by the pipe symbol using split("|")

You can also use .split("[|]").

(I used this instead of .split("\\|"), which didn't work for me.)

Compare objects in Angular

Assuming that the order is the same in both objects, just stringify them both and compare!

JSON.stringify(obj1) == JSON.stringify(obj2);

What is the difference between readonly="true" & readonly="readonly"?

This is a property setting rather than a valued attribute

These property settings are values per see and don't need any assignments to them. When they are present, an element has this boolean property set to true, when they're absent they're false.

<input type="text" readonly />

It's actually browsers that are liberal toward value assignment to them. If you assign any value to them it will simply get ignored. Browsers will only see the presence of a particular property and ignore the value you're trying to assign to them.

This is of course good, because some frameworks don't have the ability to add such properties without providing their value along with them. Asp.net MVC Html helpers are one of them. jQuery used to be the same until version 1.6 where they added the concept of properties.

There are of course some implications that are related to XHTML as well, because attributes in XML need values in order to be well formed. But that's a different story. Hence browsers have to ignore value assignments.

Anyway. Never mind the value you're assigning to them as long as the name is correctly spelled so it will be detected by browsers. But for readability and maintainability it's better to assign meaningful values to them like:

readonly="true" <-- arguably best human readable
readonly="readonly"

as opposed to

readonly="johndoe"
readonly="01/01/2000"

that may confuse future developers maintaining your code and may interfere with future specification that may define more strict rules to such property settings.

Advantage of switch over if-else statement

If your cases are likely to remain grouped in the future--if more than one case corresponds to one result--the switch may prove to be easier to read and maintain.

How to debug a stored procedure in Toad?

Open a PL/SQL object in the Editor.

Click on the main toolbar or select Session | Toggle Compiling with Debug. This enables debugging.

Compile the object on the database.

Select one of the following options on the Execute toolbar to begin debugging: Execute PL/SQL with debugger () Step over Step into Run to cursor

Drop a temporary table if it exists

Check for the existence by retrieving its object_id:

if object_id('tempdb..##clients_keyword') is not null
    drop table ##clients_keyword

Android getting value from selected radiobutton

In case, if you want to do some job on the selection of one of the radio buttons (without having any additional OK button or something), your code is fine, updated little.

public class MainActivity extends Activity {

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

        RadioGroup rg = (RadioGroup) findViewById(R.id.radioGroup1);

        rg.setOnCheckedChangeListener(new RadioGroup.OnCheckedChangeListener() 
        {
            public void onCheckedChanged(RadioGroup group, int checkedId) {
                switch(checkedId){
                    case R.id.radio0:
                        // do operations specific to this selection
                        break;
                    case R.id.radio1:
                        // do operations specific to this selection
                        break;
                    case R.id.radio2:
                        // do operations specific to this selection
                        break;
                }   
            }
        });
    }
}

How to find list intersection?

Make a set out of the larger one:

_auxset = set(a)

Then,

c = [x for x in b if x in _auxset]

will do what you want (preserving b's ordering, not a's -- can't necessarily preserve both) and do it fast. (Using if x in a as the condition in the list comprehension would also work, and avoid the need to build _auxset, but unfortunately for lists of substantial length it would be a lot slower).

If you want the result to be sorted, rather than preserve either list's ordering, an even neater way might be:

c = sorted(set(a).intersection(b))

How do I programmatically click a link with javascript?

If you only want to change the current page address, you can do that by simply doing this in Javascript :

location.href = "http://www.example.com/test";

How does the communication between a browser and a web server take place?

Your browser first resolves the servername via DNS to an IP. Then it opens a TCP connection to the webserver and tries to communicate via HTTP. Usually that is on TCP-port 80 but you can specify a different one (http://server:portnumber).

HTTP looks like this:

Once it is connected, it sends the request, which looks like:

GET /site HTTP/1.0
Header1: bla
Header2: blub
{emptyline}

E.g., a header might be Authorization or Range. See here for more.

Then the server responds like this:

200 OK
Header3: foo
Header4: bar

content following here...

E.g., a header might be Date or Content-Type. See here for more.

Look at Wikipedia for HTTP for some more information about this protocol.

Retrieving JSON Object Literal from HttpServletRequest

If you're trying to get data out of the request body, the code above works. But, I think you are having the same problem I was..

If the data in the body is in JSON form, and you want it as a Java object, you'll need to parse it yourself, or use a library like google-gson to handle it for you. You should look at the docs and examples at the project's website to know how to use it. It's fairly simple.

The difference between bracket [ ] and double bracket [[ ]] for accessing the elements of a list or dataframe

The R Language Definition is handy for answering these types of questions:

R has three basic indexing operators, with syntax displayed by the following examples

    x[i]
    x[i, j]
    x[[i]]
    x[[i, j]]
    x$a
    x$"a"

For vectors and matrices the [[ forms are rarely used, although they have some slight semantic differences from the [ form (e.g. it drops any names or dimnames attribute, and that partial matching is used for character indices). When indexing multi-dimensional structures with a single index, x[[i]] or x[i] will return the ith sequential element of x.

For lists, one generally uses [[ to select any single element, whereas [ returns a list of the selected elements.

The [[ form allows only a single element to be selected using integer or character indices, whereas [ allows indexing by vectors. Note though that for a list, the index can be a vector and each element of the vector is applied in turn to the list, the selected component, the selected component of that component, and so on. The result is still a single element.

How to get the browser viewport dimensions?

A solution that would conform to W3C standards would be to create a transparent div (for example dynamically with JavaScript), set its width and height to 100vw/100vh (Viewport units) and then get its offsetWidth and offsetHeight. After that, the element can be removed again. This will not work in older browsers because the viewport units are relatively new, but if you don't care about them but about (soon-to-be) standards instead, you could definitely go this way:

var objNode = document.createElement("div");
objNode.style.width  = "100vw";
objNode.style.height = "100vh";
document.body.appendChild(objNode);
var intViewportWidth  = objNode.offsetWidth;
var intViewportHeight = objNode.offsetHeight;
document.body.removeChild(objNode);

Of course, you could also set objNode.style.position = "fixed" and then use 100% as width/height - this should have the same effect and improve compatibility to some extent. Also, setting position to fixed might be a good idea in general, because otherwise the div will be invisible but consume some space, which will lead to scrollbars appearing etc.

Only get hash value using md5sum (without filename)

If you need to print it and don't need a newline, you can use:

printf $(md5sum filename)

Python DNS module import error

ok to resolve this First install dns for python by cmd using pip install dnspython
(if you use conda first type activate and then you will go in base (in cmd) and then type above code) it will install it in anaconda site package ,copy the location of that site package folder from cmd, and open it . Now copy all dns folders and paste them in python site package folder. it will resolve it .

actually the thing is our code is not able to find the specified package in python\site package bcz it is in anaconda\site package. so you have to COPY IT (not cut).

How do I write dispatch_after GCD in Swift 3, 4, and 5?

A somewhat different flavour of the Accepted Answer.

Swift 4

DispatchQueue.main.asyncAfter(deadline: .now() + 0.1 + .milliseconds(500) + 
.microseconds(500) + .nanoseconds(1000)) {
                print("Delayed by 0.1 second + 500 milliseconds + 500 microseconds + 
                      1000 nanoseconds)")
 }

How do CSS triangles work?

I know this is an old one, but I'd like to add to this discussion that There are at least 5 different methods for creating a triangle using HTML & CSS alone.

  1. Using borders
  2. Using linear-gradient
  3. Using conic-gradient
  4. Using transform and overflow
  5. Using clip-path

I think that all have been covered here except for method 3, using the conic-gradient, so I will share it here:

_x000D_
_x000D_
.triangle{_x000D_
        width: 40px;_x000D_
        height: 40px;_x000D_
        background: conic-gradient(at 50% 50%,transparent 135deg,green 0,green 225deg, transparent 0);_x000D_
    }
_x000D_
<div class="triangle"></div>
_x000D_
_x000D_
_x000D_

Create CSS Triangles Using Conic Gradient

Casting to string in JavaScript

They do behave differently when the value is null.

  • null.toString() throws an error - Cannot call method 'toString' of null
  • String(null) returns - "null"
  • null + "" also returns - "null"

Very similar behaviour happens if value is undefined (see jbabey's answer).

Other than that, there is a negligible performance difference, which, unless you're using them in huge loops, isn't worth worrying about.

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

Try to run it as:

python3 -m p_03_using_bisection_search

What is an example of the simplest possible Socket.io example?

i realize this post is several years old now, but sometimes certified newbies such as myself need a working example that is totally stripped down to the absolute most simplest form.

every simple socket.io example i could find involved http.createServer(). but what if you want to include a bit of socket.io magic in an existing webpage? here is the absolute easiest and smallest example i could come up with.

this just returns a string passed from the console UPPERCASED.

app.js

var http = require('http');

var app = http.createServer(function(req, res) {
        console.log('createServer');
});
app.listen(3000);

var io = require('socket.io').listen(app);


io.on('connection', function(socket) {
    io.emit('Server 2 Client Message', 'Welcome!' );

    socket.on('Client 2 Server Message', function(message)      {
        console.log(message);
        io.emit('Server 2 Client Message', message.toUpperCase() );     //upcase it
    });

});

index.html:

<!doctype html>
<html>
    <head>
        <script type='text/javascript' src='http://localhost:3000/socket.io/socket.io.js'></script>
        <script type='text/javascript'>
                var socket = io.connect(':3000');
                 // optionally use io('http://localhost:3000');
                 // but make *SURE* it matches the jScript src
                socket.on ('Server 2 Client Message',
                     function(messageFromServer)       {
                        console.log ('server said: ' + messageFromServer);
                     });

        </script>
    </head>
    <body>
        <h5>Worlds smallest Socket.io example to uppercase strings</h5>
        <p>
        <a href='#' onClick="javascript:socket.emit('Client 2 Server Message', 'return UPPERCASED in the console');">return UPPERCASED in the console</a>
                <br />
                socket.emit('Client 2 Server Message', 'try cut/paste this command in your console!');
        </p>
    </body>
</html>

to run:

npm init;  // accept defaults
npm  install  socket.io  http  --save ;
node app.js  &

use something like this port test to ensure your port is open.

now browse to http://localhost/index.html and use your browser console to send messages back to the server.

at best guess, when using http.createServer, it changes the following two lines for you:

<script type='text/javascript' src='/socket.io/socket.io.js'></script>
var socket = io();

i hope this very simple example spares my fellow newbies some struggling. and please notice that i stayed away from using "reserved word" looking user-defined variable names for my socket definitions.

High CPU Utilization in java application - why?

You did not assign the "linux" to the question but you mentioned "Linux top". And thus this might be helpful:

Use the small Linux tool threadcpu to identify the most cpu using threads. It calls jstack to get the thread name. And with "sort -n" in pipe you get the list of threads ordered by cpu usage.

More details can be found here: http://www.tuxad.com/blog/archives/2018/10/01/threadcpu_-_show_cpu_usage_of_threads/index.html

And if you still need more details then create a thread dump or run strace on the thread.

Passing a variable to a powershell script via command line

Make this in your test.ps1, at the first line

param(
[string]$a
)

Write-Host $a

Then you can call it with

./Test.ps1 "Here is your text"

Found here (English)

When to use window.opener / window.parent / window.top

when you are dealing with popups window.opener plays an important role, because we have to deal with fields of parent page as well as child page, when we have to use values on parent page we can use window.opener or we want some data on the child window or popup window at the time of loading then again we can set the values using window.opener