Programs & Examples On #Nav

The `

Align nav-items to right side in bootstrap-4

In my case, I was looking for a solution that allows one of the navbar items to be right aligned. In order to do this, you must add style="width:100%;" to the <ul class="navbar-nav"> and then add the ml-auto class to your navbar item.

How to center a navigation bar with CSS or HTML?

#nav ul {
    display: inline-block;
    list-style-type: none;
}

It should work, I tested it in your site.

enter image description here

Make a nav bar stick

To make header sticky, first you have to give position: fixed; for header in css. Then you can adjust width and height etc. I would highly recommand to follow this article. How to create a sticky website header

Here is code as well to work around on header to make it sticky.

header { 
   position: fixed; 
   right: 0; 
   left: 0; 
   z-index: 999;
}

This code above will go inside your styles.css file.

React router nav bar example

Note The accepted is perfectly fine - but wanted to add a version4 example because they are different enough.

Nav.js

  import React from 'react';
  import { Link } from 'react-router';

  export default class Nav extends React.Component {
    render() {    
      return (
        <nav className="Nav">
          <div className="Nav__container">
            <Link to="/" className="Nav__brand">
              <img src="logo.svg" className="Nav__logo" />
            </Link>

            <div className="Nav__right">
              <ul className="Nav__item-wrapper">
                <li className="Nav__item">
                  <Link className="Nav__link" to="/path1">Link 1</Link>
                </li>
                <li className="Nav__item">
                  <Link className="Nav__link" to="/path2">Link 2</Link>
                </li>
                <li className="Nav__item">
                  <Link className="Nav__link" to="/path3">Link 3</Link>
                </li>
              </ul>
            </div>
          </div>
        </nav>
      );
    }
  }

App.js

  import React from 'react';
  import { Link, Switch, Route } from 'react-router';
  import Nav from './nav';
  import Page1 from './page1';
  import Page2 from './page2';
  import Page3 from './page3';

  export default class App extends React.Component {
    render() {    
      return (
        <div className="App">
          <Router>
            <div>
              <Nav />
              <Switch>
                <Route exactly component={Landing} pattern="/" />
                <Route exactly component={Page1} pattern="/path1" />
                <Route exactly component={Page2} pattern="/path2" />
                <Route exactly component={Page3} pattern="/path3" />
                <Route component={Page404} />
              </Switch>
            </div>
          </Router>
        </div>
      );
    }
  }

Alternatively, if you want a more dynamic nav, you can look at the excellent v4 docs: https://reacttraining.com/react-router/web/example/sidebar

Edit

A few people have asked about a page without the Nav, such as a login page. I typically approach it with a wrapper Route component

  import React from 'react';
  import { Link, Switch, Route } from 'react-router';
  import Nav from './nav';
  import Page1 from './page1';
  import Page2 from './page2';
  import Page3 from './page3';

  const NavRoute = ({exact, path, component: Component}) => (
    <Route exact={exact} path={path} render={(props) => (
      <div>
        <Header/>
        <Component {...props}/>
      </div>
    )}/>
  )

  export default class App extends React.Component {
    render() {    
      return (
        <div className="App">
          <Router>
              <Switch>
                <NavRoute exactly component={Landing} pattern="/" />
                <Route exactly component={Login} pattern="/login" />
                <NavRoute exactly component={Page1} pattern="/path1" />
                <NavRoute exactly component={Page2} pattern="/path2" />
                <NavRoute component={Page404} />
              </Switch>
          </Router>
        </div>
      );
    }
  }

How to create a sticky navigation bar that becomes fixed to the top after scrolling

I have found this simple javascript snippet very useful.

$(document).ready(function()
{
    var navbar = $('#navbar');

    navbar.after('<div id="more-div" style="height: ' + navbar.outerHeight(true) + 'px" class="hidden"></div>');
    var afternavbar = $('#more-div');

    var abovenavbar = $('#above-navbar');

    $(window).on('scroll', function()
    {
        if ($(window).scrollTop() > abovenavbar.height())
        {
            navbar.addClass('navbar-fixed-top');
            afternavbar.removeClass('hidden');
        }
        else
        {
            navbar.removeClass('navbar-fixed-top');
            afternavbar.addClass('hidden');
        }
    });
});

Changing color of Twitter bootstrap Nav-Pills

Bootstrap 4.x Solution

.nav-pills .nav-link.active {
    background-color: #ff0000 !important;
}

Salt and hash a password in Python

Based on the other answers to this question, I've implemented a new approach using bcrypt.

Why use bcrypt

If I understand correctly, the argument to use bcrypt over SHA512 is that bcrypt is designed to be slow. bcrypt also has an option to adjust how slow you want it to be when generating the hashed password for the first time:

# The '12' is the number that dictates the 'slowness'
bcrypt.hashpw(password, bcrypt.gensalt( 12 ))

Slow is desirable because if a malicious party gets their hands on the table containing hashed passwords, then it is much more difficult to brute force them.

Implementation

def get_hashed_password(plain_text_password):
    # Hash a password for the first time
    #   (Using bcrypt, the salt is saved into the hash itself)
    return bcrypt.hashpw(plain_text_password, bcrypt.gensalt())

def check_password(plain_text_password, hashed_password):
    # Check hashed password. Using bcrypt, the salt is saved into the hash itself
    return bcrypt.checkpw(plain_text_password, hashed_password)

Notes

I was able to install the library pretty easily in a linux system using:

pip install py-bcrypt

However, I had more trouble installing it on my windows systems. It appears to need a patch. See this Stack Overflow question: py-bcrypt installing on win 7 64bit python

How do I use Notepad++ (or other) with msysgit?

Update 2010-2011:

zumalifeguard's solution (upvoted) is simpler than the original one, as it doesn't need anymore a shell wrapper script.

As I explain in "How can I set up an editor to work with Git on Windows?", I prefer a wrapper, as it is easier to try and switch editors, or change the path of one editor, without having to register said change with a git config again.
But that is just me.


Additional information: the following solution works with Cygwin, while the zuamlifeguard's solution does not.


Original answer.

The following:

C:\prog\git>git config --global core.editor C:/prog/git/npp.sh

C:/prog/git/npp.sh:
#!/bin/sh
"c:/Program Files/Notepad++/notepad++.exe" -multiInst "$*"

does work. Those commands are interpreted as shell script, hence the idea to wrap any windows set of commands in a sh script.
(As Franky comments: "Remember to save your .sh file with Unix style line endings or receive mysterious error messages!")

More details on the SO question How can I set up an editor to work with Git on Windows?

Note the '-multiInst' option, for ensuring a new instance of notepad++ for each call from Git.

Note also that, if you are using Git on Cygwin (and want to use Notepad++ from Cygwin), then scphantm explains in "using Notepad++ for Git inside Cygwin" that you must be aware that:

git is passing it a cygwin path and npp doesn't know what to do with it

So the script in that case would be:

#!/bin/sh
"C:/Program Files (x86)/Notepad++/notepad++.exe" -multiInst -notabbar -nosession -noPlugin "$(cygpath -w "$*")"

Multiple lines for readability:

#!/bin/sh
"C:/Program Files (x86)/Notepad++/notepad++.exe" -multiInst -notabbar \
  -nosession -noPlugin "$(cygpath -w "$*")"

With "$(cygpath -w "$*")" being the important part here.

Val commented (and then deleted) that you should not use -notabbar option:

It makes no good to disable the tab during rebase, but makes a lot of harm to general Notepad usability since -notab becomes the default setting and you must Settings>Preferences>General>TabBar> Hide>uncheck every time you start notepad after rebase. This is hell. You recommended the hell.

So use rather:

#!/bin/sh
"C:/Program Files (x86)/Notepad++/notepad++.exe" -multiInst -nosession -noPlugin "$(cygpath -w "$*")"

That is:

#!/bin/sh
"C:/Program Files (x86)/Notepad++/notepad++.exe" -multiInst -nosession \
  -noPlugin "$(cygpath -w "$*")"

If you want to place the script 'npp.sh' in a path with spaces (as in 'c:\program files\...',), you have three options:

  • Either try to quote the path (single or double quotes), as in:

    git config --global core.editor 'C:/program files/git/npp.sh'
    
  • or try the shortname notation (not fool-proofed):

    git config --global core.editor C:/progra~1/git/npp.sh
    
  • or (my favorite) place 'npp.sh' in a directory part of your %PATH% environment variable. You would not have then to specify any path for the script.

    git config --global core.editor npp.sh
    
  • Steiny reports in the comments having to do:

    git config --global core.editor '"C:/Program Files (x86)/Git/scripts/npp.sh"'
    

C Linking Error: undefined reference to 'main'

You should provide output file name after -o option. In your case runexp.o is treated as output file name, not input object file and thus your main function is undefined.

Command-line Tool to find Java Heap Size and Memory Used (Linux)?

If using jrockit try the jrcmd command line tool. For example:

$ jrcmd 5127 print_memusage
5127:
Total mapped                  1074596KB           (reserved=3728KB)
-              Java heap       786432KB           (reserved=0KB)
-              GC tables        26316KB          
-          Thread stacks        13452KB           (#threads=34)
-          Compiled code         9856KB           (used=9761KB)
-               Internal          840KB          
-                     OS        15036KB          
-                  Other       146632KB          
-        Java class data        75008KB           (malloced=74861KB #103221 in 18709 classes)
- Native memory tracking         1024KB           (malloced=102KB #8)

For more commands, like heap_diagnostics, use "jrcmd help" to list them.

https://blogs.oracle.com/jrockit/entry/why_is_my_jvm_process_larger_t

Add characters to a string in Javascript

It sounds like you want to use join, e.g.:

var text = list.join();

Is it possible to make input fields read-only through CSS?

This is not possible with css, but I have used one css trick in one of my website, please check if this works for you.

The trick is: wrap the input box with a div and make it relative, place a transparent image inside the div and make it absolute over the input text box, so that no one can edit it.

css

.txtBox{
    width:250px;
    height:25px;
    position:relative;
}
.txtBox input{
    width:250px;
    height:25px;
}
.txtBox img{
    position:absolute;
    top:0;
    left:0
}

html

<div class="txtBox">
<input name="" type="text" value="Text Box" />
<img src="http://dev.w3.org/2007/mobileok-ref/test/data/ROOT/GraphicsForSpacingTest/1/largeTransparent.gif" width="250" height="25" alt="" />
</div>

jsFiddle File

package javax.servlet.http does not exist

The solution that work for is were add the next dependency to my pom.xml file.

<dependency>
        <groupId>javax.servlet</groupId>
        <artifactId>javax.servlet-api</artifactId>
        <version>3.0.1</version>
        <scope>provided</scope>
</dependency>

Angular - "has no exported member 'Observable'"

Just put:

import { Observable} from 'rxjs';

Just like that. Nothing more or less.

Auto-increment primary key in SQL tables

Right-click on the table in SSMS, 'Design' it, and click on the id column. In the properties, set the identity to be seeded @ e.g. 1 and to have increment of 1 - save and you're done.

How to make a WPF window be on top of all other windows of my app (not system wide)?

You can add this to your windows tags

WindowStartupLocation="CenterScreen"

Then you can also display it if you want your users to acknowledge it in order to proceed

YourWindow.ShowDialog();

First try it without TopMost parameters and see the results.

/usr/lib/libstdc++.so.6: version `GLIBCXX_3.4.15' not found

For this error, I copied the latest libstdc++.so.6.0.17 from other server, and removed the soft link and recreated it.

1. Copy the the libstdc++.so.6.0.15 or latest from other server to the affected system.
In my case SUSE linux 11 SP3 had latest.
2. rm libstdc++.so.6
3. ln -s libstdc++.so.6.0.17 libstdc++.so.6 (under /usr/lib64 directory).

nJoy

Generating Random Passwords

On my website I use this method:

    //Symb array
    private const string _SymbolsAll = "~`!@#$%^&*()_+=-\\|[{]}'\";:/?.>,<";

    //Random symb
    public string GetSymbol(int Length)
    {
        Random Rand = new Random(DateTime.Now.Millisecond);
        StringBuilder result = new StringBuilder();
        for (int i = 0; i < Length; i++)
            result.Append(_SymbolsAll[Rand.Next(0, _SymbolsAll.Length)]);
        return result.ToString();
    }

Edit string _SymbolsAll for your array list.

How to get current user who's accessing an ASP.NET application?

The general consensus answer above seems to have have a compatibility issue with CORS support. In order to use the HttpContext.Current.User.Identity.Name attribute you must disable anonymous authentication in order to force Windows authentication to provide the authenticated user information. Unfortunately, I believe you must have anonymous authentication enabled in order to process the pre-flight OPTIONS request in a CORS scenario.

You can get around this by leaving anonymous authentication enabled and using the HttpContext.Current.Request.LogonUserIdentity attribute instead. This will return the authenticated user information (assuming you are in an intranet scenario) even with anonymous authentication enabled. The attribute returns a WindowsUser data structure and both are defined in the System.Web namespace

        using System.Web;
        WindowsIdentity user;
        user  = HttpContext.Current.Request.LogonUserIdentity;

Why is Node.js single threaded?

Node.js was created explicitly as an experiment in async processing. The theory was that doing async processing on a single thread could provide more performance and scalability under typical web loads than the typical thread-based implementation.

And you know what? In my opinion that theory's been borne out. A node.js app that isn't doing CPU intensive stuff can run thousands more concurrent connections than Apache or IIS or other thread-based servers.

The single threaded, async nature does make things complicated. But do you honestly think it's more complicated than threading? One race condition can ruin your entire month! Or empty out your thread pool due to some setting somewhere and watch your response time slow to a crawl! Not to mention deadlocks, priority inversions, and all the other gyrations that go with multithreading.

In the end, I don't think it's universally better or worse; it's different, and sometimes it's better and sometimes it's not. Use the right tool for the job.

Swing/Java: How to use the getText and setText string properly

the getText method returns a String, while the setText receives a String, so you can write it like label1.setText(nameField.getText()); in your listener.

How can I make grep print the lines below and above each matching line?

Use -A and -B switches (mean lines-after and lines-before):

grep -A 1 -B 1 FAILED file.txt

C - casting int to char and append char to char

Casting int to char is done simply by assigning with the type in parenthesis:

int i = 65535;
char c = (char)i;

Note: I thought that you might be losing data (as in the example), because the type sizes are different.

Appending characters to characters cannot be done (unless you mean arithmetics, then it's simple operators). You need to use strings, AKA arrays of characters, and <string.h> functions like strcat or sprintf.

Opposite of %in%: exclude rows with values specified in a vector

The package collapse has it built in: %!in%.

How to export a table dataframe in PySpark to csv?

If you cannot use spark-csv, you can do the following:

df.rdd.map(lambda x: ",".join(map(str, x))).coalesce(1).saveAsTextFile("file.csv")

If you need to handle strings with linebreaks or comma that will not work. Use this:

import csv
import cStringIO

def row2csv(row):
    buffer = cStringIO.StringIO()
    writer = csv.writer(buffer)
    writer.writerow([str(s).encode("utf-8") for s in row])
    buffer.seek(0)
    return buffer.read().strip()

df.rdd.map(row2csv).coalesce(1).saveAsTextFile("file.csv")

Include .so library in apk in android studio

I had the same problem. Check out the comment in https://gist.github.com/khernyo/4226923#comment-812526

It says:

for gradle android plugin v0.3 use "com.android.build.gradle.tasks.PackageApplication"

That should fix your problem.

UITableView Separator line

First you can write the code:

{    [self.tableView setSeparatorStyle:UITableViewCellSeparatorStyleNone];}

after that

{    #define cellHeight 80 // You can change according to your req.<br>
     #define cellWidth 320 // You can change according to your req.<br>

    -(UITableViewCell *)tableView:(UITableView *)tableView cellForRowAtIndexPath:(NSIndexPath  *)indexPath
    {
         UIImageView *imgView = [[UIImageView alloc] initWithImage:[UIImage imageNamed:@"seprater_line.png"]];
        imgView.frame = CGRectMake(0, cellHeight, cellWidth, 1);
        [customCell.contentView addSubview:imgView];
         return  customCell;

     }
}

Can't push to the heroku

If you are a python user -
Create a requirements.txt file preferably using pip freeze > requirements.txt.
Add, commit and try pushing it again.

If this doesn't work try deleting .git (beware this might remove the associated git history) and follow the above steps again.

Worked for me.

Efficient way to return a std::vector in c++

If the compiler supports Named Return Value Optimization (http://msdn.microsoft.com/en-us/library/ms364057(v=vs.80).aspx), you can directly return the vector provide that there is no:

  1. Different paths returning different named objects
  2. Multiple return paths (even if the same named object is returned on all paths) with EH states introduced.
  3. The named object returned is referenced in an inline asm block.

NRVO optimizes out the redundant copy constructor and destructor calls and thus improves overall performance.

There should be no real diff in your example.

Spring JUnit: How to Mock autowired component in autowired component

Another approach in integration testing is to define a new Configuration class and provide it as your @ContextConfiguration. Into the configuration you will be able to mock your beans and also you must define all types of beans which you are using in test/s flow. To provide an example :

@RunWith(SpringRunner.class)
@ContextConfiguration(loader = AnnotationConfigContextLoader.class)
public class MockTest{
 @Configuration
 static class ContextConfiguration{
 // ... you beans here used in test flow
 @Bean
    public MockMvc mockMvc() {
        return MockMvcBuilders.standaloneSetup(/*you can declare your controller beans defines on top*/)
                .addFilters(/*optionally filters*/).build();
    }
 //Defined a mocked bean
 @Bean
    public MyService myMockedService() {
        return Mockito.mock(MyService.class);
    }
 }

 @Autowired
 private MockMvc mockMvc;

 @Autowired
 MyService myMockedService;

 @Before
 public void setup(){
  //mock your methods from MyService bean 
  when(myMockedService.myMethod(/*params*/)).thenReturn(/*my answer*/);
 }

 @Test
 public void test(){
  //test your controller which trigger the method from MyService
  MvcResult result = mockMvc.perform(get(CONTROLLER_URL)).andReturn();
  // do your asserts to verify
 }
}

How to set top-left alignment for UILabel for iOS application?

As you are using the interface builder, set the constraints for your label (be sure to set the height and width as well). Then in the Size Inspector, check the height for the label. There you will want it to read >= instead of =. Then in the implementation for that view controller, set the number of lines to 0 (can also be done in IB) and set the label [label sizeToFit]; and as your text gains length, the label will grow in height and keep your text in the upper left.

elasticsearch bool query combine must with OR

I finally managed to create a query that does exactly what i wanted to have:

A filtered nested boolean query. I am not sure why this is not documented. Maybe someone here can tell me?

Here is the query:

GET /test/object/_search
{
  "from": 0,
  "size": 20,
  "sort": {
    "_score": "desc"
  },
  "query": {
    "filtered": {
      "filter": {
        "bool": {
          "must": [
            {
              "term": {
                "state": 1
              }
            }
          ]
        }
      },
      "query": {
        "bool": {
          "should": [
            {
              "bool": {
                "must": [
                  {
                    "match": {
                      "name": "foo"
                    }
                  },
                  {
                    "match": {
                      "name": "bar"
                    }
                  }
                ],
                "should": [
                  {
                    "match": {
                      "has_image": {
                        "query": 1,
                        "boost": 100
                      }
                    }
                  }
                ]
              }
            },
            {
              "bool": {
                "must": [
                  {
                    "match": {
                      "info": "foo"
                    }
                  },
                  {
                    "match": {
                      "info": "bar"
                    }
                  }
                ],
                "should": [
                  {
                    "match": {
                      "has_image": {
                        "query": 1,
                        "boost": 100
                      }
                    }
                  }
                ]
              }
            }
          ],
          "minimum_should_match": 1
        }
      }    
    }
  }
}

In pseudo-SQL:

SELECT * FROM /test/object
WHERE 
    ((name=foo AND name=bar) OR (info=foo AND info=bar))
AND state=1

Please keep in mind that it depends on your document field analysis and mappings how name=foo is internally handled. This can vary from a fuzzy to strict behavior.

"minimum_should_match": 1 says, that at least one of the should statements must be true.

This statements means that whenever there is a document in the resultset that contains has_image:1 it is boosted by factor 100. This changes result ordering.

"should": [
  {
    "match": {
      "has_image": {
        "query": 1,
        "boost": 100
      }
    }
   }
 ]

Have fun guys :)

How can I find the maximum value and its index in array in MATLAB?

The function is max. To obtain the first maximum value you should do

[val, idx] = max(a);

val is the maximum value and idx is its index.

What are some uses of template template parameters?

I use it for versioned types.

If you have a type versioned through a template such as MyType<version>, you can write a function in which you can capture the version number:

template<template<uint8_t> T, uint8_t Version>
Foo(const T<Version>& obj)
{
    assert(Version > 2 && "Versions older than 2 are no longer handled");
    ...
    switch (Version)
    {
    ...
    }
}

So you can do different things depending on the version of the type being passed in instead of having an overload for each type. You can also have conversion functions which take in MyType<Version> and return MyType<Version+1>, in a generic way, and even recurse them to have a ToNewest() function which returns the latest version of a type from any older version (very useful for logs that might have been stored a while back but need to be processed with today's newest tool).

toBe(true) vs toBeTruthy() vs toBeTrue()

Disclamer: This is just a wild guess

I know everybody loves an easy-to-read list:

  • toBe(<value>) - The returned value is the same as <value>
  • toBeTrue() - Checks if the returned value is true
  • toBeTruthy() - Check if the value, when cast to a boolean, will be a truthy value

    Truthy values are all values that aren't 0, '' (empty string), false, null, NaN, undefined or [] (empty array)*.

    * Notice that when you run !![], it returns true, but when you run [] == false it also returns true. It depends on how it is implemented. In other words: (!![]) === ([] == false)


On your example, toBe(true) and toBeTrue() will yield the same results.

The current .NET SDK does not support targeting .NET Standard 2.0 error in Visual Studio 2017 update 15.3

I had installations of both Visual Studio 2019 and 2017. I tried installing the .NET Core 2.X SDK for VS2017 separately but with no luck.

The issue is, that I have .NET Core 3.0 SDK installed as default sdk-version, which VS2017 does not like.

My solution was to switch the SDK version for the specific project.

  • First, list your installed SDK's to find the desired version:
$ dotnet --info

.NET Core SDK (reflecting any global.json):
 Version:   3.1.100
 Commit:    cd82f021f4

Runtime Environment:
 OS Name:     Windows
 OS Version:  10.0.18362
 OS Platform: Windows
 RID:         win10-x64
 Base Path:   C:\Program Files\dotnet\sdk\3.1.100\

Host (useful for support):
  Version: 3.1.0
  Commit:  65f04fb6db

.NET Core SDKs installed:
  1.1.14 [C:\Program Files\dotnet\sdk]
  2.1.202 [C:\Program Files\dotnet\sdk]
  2.1.509 [C:\Program Files\dotnet\sdk]
  2.2.110 [C:\Program Files\dotnet\sdk]
  3.0.100 [C:\Program Files\dotnet\sdk]
  3.1.100 [C:\Program Files\dotnet\sdk]
  • From your solution directory:
$ dotnet new globaljson --sdk-version 2.2.110 --force

Now, dotnet will use the specified SDK version for this solution.

I have not found a way to do this system-wide without also messing up my 3.0 projects.

while installing vc_redist.x64.exe, getting error "Failed to configure per-machine MSU package."

The OS failed to install the required update Windows8.1-KB2999226-x64.msu. However I tried to find the particular update from -

C:\ProgramData\Package Cache\469A82B09E217DDCF849181A586DF1C97C0C5C85\packages\Patch\amd64\Windows8.1-KB2999226-x64.msu.

I couldn't find it there so I installed the kb2999226 update from here (Windows 10 Universal C runtime)

Then I installed the update according to my OS and after that It was working fine.

Creating Accordion Table with Bootstrap

This seems to be already asked before:

This might help:

Twitter Bootstrap Use collapse.js on table cells [Almost Done]

UPDATE:

Your fiddle wasn't loading jQuery, so anything worked.

<table class="table table-hover">
<thead>
  <tr>
    <th></th>
    <th></th>
    <th></th>
  </tr>
</thead>

<tbody>
    <tr data-toggle="collapse" data-target="#accordion" class="clickable">
        <td>Some Stuff</td>
        <td>Some more stuff</td>
        <td>And some more</td>
    </tr>
    <tr>
        <td colspan="3">
            <div id="accordion" class="collapse">Hidden by default</div>
        </td>
    </tr>
</tbody>
</table>

Try this one: http://jsfiddle.net/Nb7wy/2/

I also added colspan='2' to the details row. But it's essentially your fiddle with jQuery loaded (in frameworks in the left column)

Why does foo = filter(...) return a <filter object>, not a list?

Have a look at the python documentation for filter(function, iterable) (from here):

Construct an iterator from those elements of iterable for which function returns true.

So in order to get a list back you have to use list class:

shesaid = list(filter(greetings(), ["hello", "goodbye"]))

But this probably isn't what you wanted, because it tries to call the result of greetings(), which is "hello", on the values of your input list, and this won't work. Here also the iterator type comes into play, because the results aren't generated until you use them (for example by calling list() on it). So at first you won't get an error, but when you try to do something with shesaid it will stop working:

>>> print(list(shesaid))
Traceback (most recent call last):
  File "<stdin>", line 1, in <module>
TypeError: 'str' object is not callable

If you want to check which elements in your list are equal to "hello" you have to use something like this:

shesaid = list(filter(lambda x: x == "hello", ["hello", "goodbye"]))

(I put your function into a lambda, see Randy C's answer for a "normal" function)

Can an angular directive pass arguments to functions in expressions specified in the directive's attributes?

For me following worked:

in directive declare it like this:

.directive('myDirective', function() {
    return {
        restrict: 'E',
        replace: true,
        scope: {
            myFunction: '=',
        },
        templateUrl: 'myDirective.html'
    };
})  

In directive template use it in following way:

<select ng-change="myFunction(selectedAmount)">

And then when you use the directive, pass the function like this:

<data-my-directive
    data-my-function="setSelectedAmount">
</data-my-directive>

You pass the function by its declaration and it is called from directive and parameters are populated.

How can the Euclidean distance be calculated with NumPy?

I like np.dot (dot product):

a = numpy.array((xa,ya,za))
b = numpy.array((xb,yb,zb))

distance = (np.dot(a-b,a-b))**.5

How do I merge changes to a single file, rather than merging commits?

You can checkout the old version of the file to merge, saving it under a different name, then run whatever your merge tool is on the two files.

eg.

git show B:src/common/store.ts > /tmp/store.ts (where B is the branch name/commit/tag)

meld src/common/store.ts /tmp/store.ts

Access index of last element in data frame

Pandas supports NumPy syntax which allows:

df[len(df) -1:].index[0]

Windows Explorer "Command Prompt Here"

As a very quick solution I can give you this. I tested this on Windows 8.1

1- Find File and Right Click on Command Prompt on File Explorer and then add command prompt to your Quick Access Toolbar:

Instruction 1

2- After adding it you can access the folder from here:

Instruction 2

That will open a command prompt in there for you.

Javascript how to split newline

Here is example with console.log instead of alert(). It is more convenient :)

var parse = function(){
  var str = $('textarea').val();
  var results = str.split("\n");
  $.each(results, function(index, element){
    console.log(element);
  });
};

$(function(){
  $('button').on('click', parse);
});

You can try it here

Angular + Material - How to refresh a data source (mat-table)

I achieved a good solution using two resources:

refreshing both dataSource and paginator:

this.dataSource.data = this.users;
this.dataSource.connect().next(this.users);
this.paginator._changePageSize(this.paginator.pageSize);

where for example dataSource is defined here:

    users: User[];
    ...
    dataSource = new MatTableDataSource(this.users);
    ...
    this.dataSource.paginator = this.paginator;
    ...

Python - List of unique dictionaries

Well all the answers mentioned here are good, but in some answers one can face error if the dictionary items have nested list or dictionary, so I propose simple answer

a = [str(i) for i in a]
a = list(set(a))
a = [eval(i) for i in a]

Difference between filter and filter_by in SQLAlchemy

filter_by uses keyword arguments, whereas filter allows pythonic filtering arguments like filter(User.name=="john")

Create an enum with string values

In TypeScript 0.9.0.1, although it occurs a compiler error, the compiler can still compile the ts file into js file. The code works as we expected and Visual Studio 2012 can support for automatic code completion.

Update :

In syntax, TypeScript doesn't allow us to create an enum with string values, but we can hack the compiler :p

enum Link
{
    LEARN   =   <any>'/Tutorial',
    PLAY    =   <any>'/Playground',
    GET_IT  =   <any>'/#Download',
    RUN_IT  =   <any>'/Samples',
    JOIN_IN =   <any>'/#Community'
}

alert('Link.LEARN:    '                     + Link.LEARN);
alert('Link.PLAY:    '                      + Link.PLAY);
alert('Link.GET_IT:    '                    + Link.GET_IT);
alert('Link[\'/Samples\']:    Link.'        + Link['/Samples']);
alert('Link[\'/#Community\']    Link.'      + Link['/#Community']);

Playground

Creating a thumbnail from an uploaded image

<?php 
error_reporting(0);

$change="";
$abc="";


 define ("MAX_SIZE","4000");
 function getExtension($str) {
         $i = strrpos($str,".");
         if (!$i) { return ""; }
         $l = strlen($str) - $i;
         $ext = substr($str,$i+1,$l);
         return $ext;
 }

 $errors=0;

 if($_SERVER["REQUEST_METHOD"] == "POST")
 {
    $image =$_FILES["file"]["name"];
    $uploadedfile = $_FILES['file']['tmp_name'];


    if ($image) 
    {

        $filename = stripslashes($_FILES['file']['name']);

        $extension = getExtension($filename);
        $extension = strtolower($extension);


 if (($extension != "jpg") && ($extension != "jpeg") && ($extension != "png") && ($extension != "gif")) 
        {

            $change='<div class="msgdiv">Unknown Image extension </div> ';
            $errors=1;
        }
        else
        {

 $size=filesize($_FILES['file']['tmp_name']);


if ($size > MAX_SIZE*1024)
{
    $change='<div class="msgdiv">You have exceeded the size limit!</div> ';
    $errors=1;
}


if($extension=="jpg" || $extension=="jpeg" )
{
$uploadedfile = $_FILES['file']['tmp_name'];
$src = imagecreatefromjpeg($uploadedfile);

}
else if($extension=="png")
{
$uploadedfile = $_FILES['file']['tmp_name'];
$src = imagecreatefrompng($uploadedfile);

}
else 
{
$src = imagecreatefromgif($uploadedfile);
}

echo $scr;

list($width,$height)=getimagesize($uploadedfile);


$newwidth=45;
$newheight=45;
$tmp=imagecreatetruecolor($newwidth,$newheight);


$newwidth1=90;
$newheight1=90;
$tmp1=imagecreatetruecolor($newwidth1,$newheight1);

$tmp2=imagecreatetruecolor($width,$height);
imagecopyresampled($tmp,$src,0,0,0,0,$newwidth,$newheight,$width,$height);

imagecopyresampled($tmp1,$src,0,0,0,0,$newwidth1,$newheight1,$width,$height);

imagecopyresampled($tmp2,$src,0,0,0,0,$width,$height,$width,$height);

$filename = "images/1-". $_FILES['file']['name']=time();

$filename1 = "images/2-". $_FILES['file']['name']=time();

$filename2 = "images/3-". $_FILES['file']['name']=time();

imagejpeg($tmp,$filename,100);

imagejpeg($tmp1,$filename1,100);

imagejpeg($tmp2,$filename2,100);

imagedestroy($src);
imagedestroy($tmp);
imagedestroy($tmp1);
}}

}
 if(isset($_POST['Submit']) && !$errors) 
 {

   // mysql_query("update {$prefix}users set img='$big',img_small='$small' where user_id='$user'");
    $change=' <div class="msgdiv">Image Uploaded Successfully!</div>';
 }

?>
<html xml:lang="en" xmlns="http://www.w3.org/1999/xhtml" lang="en"><head>
    <title>picture demo</title>

   <link href=".css" media="screen, projection" rel="stylesheet" type="text/css">
    <script type="text/javascript" src="http://ajax.googleapis.com/ajax/libs/jquery/1.3.0/jquery.min.js"></script>
<script type="text/javascript" src="js/jquery_002.js"></script>
<script type="text/javascript" src="js/displaymsg.js"></script>
<script type="text/javascript" src="js/ajaxdelete.js"></script>


  <style type="text/css">
  .help
{
font-size:11px; color:#006600;
}
body {
     color: #000000;
 background-color:#999999 ;
    background:#999999 url(<?php echo $user_row['img_src']; ?>) fixed repeat top left;


    font-family:"Lucida Grande", "Lucida Sans Unicode", Verdana, Arial, Helvetica, sans-serif; 

    }
        .msgdiv{
    width:759px;
padding-top:8px;
padding-bottom:8px;
background-color: #fff;
font-weight:bold;
font-size:18px;-moz-border-radius: 6px;-webkit-border-radius: 6px;
}
#container{width:763px;margin:0 auto;padding:3px 0;text-align:left;position:relative; -moz-border-radius: 6px;-webkit-border-radius: 6px; background-color:#FFFFFF }
</style>

  </head><body>
     <div align="center" id="err">
<?php echo $change; ?>  </div>
   <div id="space"></div>





  <div id="container" >

   <div id="con">



        <table width="502" cellpadding="0" cellspacing="0" id="main">
          <tbody>
            <tr>
              <td width="500" height="238" valign="top" id="main_right">

              <div id="posts">
              &nbsp;&nbsp;&nbsp;&nbsp;<img src="<?php// echo $filename; ?>" />  &nbsp;&nbsp;&nbsp;&nbsp;<img src="<?php// echo $filename1; ?>"  />
                <form method="post" action="" enctype="multipart/form-data" name="form1">
                <table width="500" border="0" align="center" cellpadding="0" cellspacing="0">
               <tr><Td style="height:25px">&nbsp;</Td></tr>
        <tr>
          <td width="150"><div align="right" class="titles">Picture 
            : </div></td>
          <td width="350" align="left">
            <div align="left">
              <input size="25" name="file" type="file" style="font-family:Verdana, Arial, Helvetica, sans-serif; font-size:10pt" class="box"/>

              </div></td>

        </tr>
        <tr><Td></Td>
        <Td valign="top" height="35px" class="help">Image maximum size <b>4000 </b>kb</span></Td>
        </tr>
        <tr><Td></Td><Td valign="top" height="35px"><input type="submit" id="mybut" value="       Upload        " name="Submit"/></Td></tr>
        <tr>
          <td width="200">&nbsp;</td>
          <td width="200"><table width="200" border="0" cellspacing="0" cellpadding="0">
              <tr>
                <td width="200" align="center"><div align="left"></div></td>
                <td width="100">&nbsp;</td>
              </tr>
          </table></td>
        </tr>
      </table>
    </form>
 </div>
            </td>

        </tr>
          </tbody>
     </table>
   </div>

  </div>



</body></html>

Clear and reset form input fields

This one works best to reset the form.

import React, { Component } from 'react'
class MyComponent extends Component {
  constructor(props){
    super(props)
    this.state = {
      inputVal: props.inputValue
    }
    // preserve the initial state in a new object
    this.baseState = this.state ///>>>>>>>>> note this one.
  }
  resetForm = () => {
    this.setState(this.baseState) ///>>>>>>>>> note this one.
  }
  submitForm = () => {
    // submit the form logic
  }
  updateInput = val => this.setState({ inputVal: val })
  render() {
    return (
      <form>
        <input
          onChange={this.updateInput}
          type="text
          value={this.state.inputVal} />
        <button
          onClick={this.resetForm}
          type="button">Cancel</button>
        <button
          onClick={this.submitForm}
          type="submit">Submit</button>
      </form>
    )
  }
}

How can I get the URL of the current tab from a Google Chrome extension?

Hi here is an Google Chrome Sample which emails the current Site to an friend. The Basic idea behind is what you want...first of all it fetches the content of the page (not interessting for you)...afterwards it gets the URL (<-- good part)

Additionally it is a nice working code example, which i prefer motstly over reading Documents.

Can be found here: Email this page

Brackets.io: Is there a way to auto indent / format <html>

I found an add-on for Brackets.io that uses auto-indent called Indentator.
It uses shortcut keys Ctrl + Alt + I

How does one convert a HashMap to a List in Java?

Collection Interface has 3 views

  • keySet
  • values
  • entrySet

Other have answered to to convert Hashmap into two lists of key and value. Its perfectly correct

My addition: How to convert "key-value pair" (aka entrySet)into list.

      Map m=new HashMap();
          m.put(3, "dev2");
          m.put(4, "dev3");

      List<Entry> entryList = new ArrayList<Entry>(m.entrySet());

      for (Entry s : entryList) {
        System.out.println(s);
      }

ArrayList has this constructor.

Why has it failed to load main-class manifest attribute from a JAR file?

I was getting the same error when i ran:
jar cvfm test.jar Test.class Manifest.txt

What resolved it was this:
jar cvfm test.jar Manifest.txt Test.class

My manifest has the entry point as given in oracle docs (make sure there is a new line character at the end of the file):
Main-Class: Test

Python unicode equal comparison failed

You may use the == operator to compare unicode objects for equality.

>>> s1 = u'Hello'
>>> s2 = unicode("Hello")
>>> type(s1), type(s2)
(<type 'unicode'>, <type 'unicode'>)
>>> s1==s2
True
>>> 
>>> s3='Hello'.decode('utf-8')
>>> type(s3)
<type 'unicode'>
>>> s1==s3
True
>>> 

But, your error message indicates that you aren't comparing unicode objects. You are probably comparing a unicode object to a str object, like so:

>>> u'Hello' == 'Hello'
True
>>> u'Hello' == '\x81\x01'
__main__:1: UnicodeWarning: Unicode equal comparison failed to convert both arguments to Unicode - interpreting them as being unequal
False

See how I have attempted to compare a unicode object against a string which does not represent a valid UTF8 encoding.

Your program, I suppose, is comparing unicode objects with str objects, and the contents of a str object is not a valid UTF8 encoding. This seems likely the result of you (the programmer) not knowing which variable holds unicide, which variable holds UTF8 and which variable holds the bytes read in from a file.

I recommend http://nedbatchelder.com/text/unipain.html, especially the advice to create a "Unicode Sandwich."

Check if a key exists inside a json object

you can do like this:

if("merchant_id" in thisSession){ /** will return true if exist */
 console.log('Exist!');
}

or

if(thisSession["merchant_id"]){ /** will return its value if exist */
 console.log('Exist!');
}

Open PDF in new browser full window

I'm going to take a chance here and actually advise against this. I suspect that people wanting to view your PDFs will already have their viewers set up the way they want, and will not take kindly to you taking that choice away from them :-)

Why not just stream down the content with the correct content specifier?

That way, newbies will get whatever their browser developer has a a useful default, and those of us that know how to configure such things will see it as we want to.

Function to get yesterday's date in Javascript in format DD/MM/YYYY

The problem here seems to be that you're reassigning $today by assigning a string to it:

$today = $dd+'/'+$mm+'/'+$yyyy;

Strings don't have getDate.

Also, $today.getDate()-1 just gives you the day of the month minus one; it doesn't give you the full date of 'yesterday'. Try this:

$today = new Date();
$yesterday = new Date($today);
$yesterday.setDate($today.getDate() - 1); //setDate also supports negative values, which cause the month to rollover.

Then just apply the formatting code you wrote:

var $dd = $yesterday.getDate();
var $mm = $yesterday.getMonth()+1; //January is 0!

var $yyyy = $yesterday.getFullYear();
if($dd<10){$dd='0'+$dd} if($mm<10){$mm='0'+$mm} $yesterday = $dd+'/'+$mm+'/'+$yyyy;

Because of the last statement, $yesterday is now a String (not a Date) containing the formatted date.

How to get input text value on click in ReactJS

First of all, you can't pass to alert second argument, use concatenation instead

alert("Input is " + inputValue);

Example

However in order to get values from input better to use states like this

_x000D_
_x000D_
var MyComponent = React.createClass({_x000D_
  getInitialState: function () {_x000D_
    return { input: '' };_x000D_
  },_x000D_
_x000D_
  handleChange: function(e) {_x000D_
    this.setState({ input: e.target.value });_x000D_
  },_x000D_
_x000D_
  handleClick: function() {_x000D_
    console.log(this.state.input);_x000D_
  },_x000D_
_x000D_
  render: function() {_x000D_
    return (_x000D_
      <div>_x000D_
        <input type="text" onChange={ this.handleChange } />_x000D_
        <input_x000D_
          type="button"_x000D_
          value="Alert the text input"_x000D_
          onClick={this.handleClick}_x000D_
        />_x000D_
      </div>_x000D_
    );_x000D_
  }_x000D_
});_x000D_
_x000D_
ReactDOM.render(_x000D_
  <MyComponent />,_x000D_
  document.getElementById('container')_x000D_
);
_x000D_
<script src="https://cdnjs.cloudflare.com/ajax/libs/react/15.1.0/react.min.js"></script>_x000D_
<script src="https://cdnjs.cloudflare.com/ajax/libs/react/15.1.0/react-dom.min.js"></script>_x000D_
<div id="container"></div>
_x000D_
_x000D_
_x000D_

Html helper for <input type="file" />

HTML Upload File ASP MVC 3.

Model: (Note that FileExtensionsAttribute is available in MvcFutures. It will validate file extensions client side and server side.)

public class ViewModel
{
    [Required, Microsoft.Web.Mvc.FileExtensions(Extensions = "csv", 
             ErrorMessage = "Specify a CSV file. (Comma-separated values)")]
    public HttpPostedFileBase File { get; set; }
}

HTML View:

@using (Html.BeginForm("Action", "Controller", FormMethod.Post, new 
                                       { enctype = "multipart/form-data" }))
{
    @Html.TextBoxFor(m => m.File, new { type = "file" })
    @Html.ValidationMessageFor(m => m.File)
}

Controller action:

[HttpPost]
public ActionResult Action(ViewModel model)
{
    if (ModelState.IsValid)
    {
        // Use your file here
        using (MemoryStream memoryStream = new MemoryStream())
        {
            model.File.InputStream.CopyTo(memoryStream);
        }
    }
}

jQuery move to anchor location on page load

Put this right before the closing Body tag at the bottom of the page.

<script>
    if (location.hash) {
        location.href = location.hash;
    }
</script>

jQuery is actually not required.

How to style child components from parent component's CSS file?

There are a few options to achieve this in Angular:

1) You can use deep css selectors

:host >>> .childrens {
     color: red;
 }

2) You can also change view encapsulation it's set to Emulated as a default but can be easily changed to Native which uses Shadow DOM native browser implementation, in your case you just need to disable it

For example:`

import { Component, ViewEncapsulation } from '@angular/core';

@Component({
  selector: 'parent',
  styles: [`
    .first {
      color:blue;
    }
    .second {
      color:red;
    }
 `],
 template: `
    <div>
      <child class="first">First</child>
      <child class="second">Second</child>
    </div>`,
  encapsulation: ViewEncapsulation.None,
 })
 export class ParentComponent  {
   constructor() {

   }
 }

How can I URL encode a string in Excel VBA?

I had problem with encoding cyrillic letters to URF-8.

I modified one of the above scripts to match cyrillic char map. Implmented is the cyrrilic section of

https://en.wikipedia.org/wiki/UTF-8 and http://www.utf8-chartable.de/unicode-utf8-table.pl?start=1024

Other sections development is sample and need verification with real data and calculate the char map offsets

Here is the script:

Public Function UTF8Encode( _
   StringToEncode As String, _
   Optional UsePlusRatherThanHexForSpace As Boolean = False _
) As String

  Dim TempAns As String
  Dim TempChr As Long
  Dim CurChr As Long
  Dim Offset As Long
  Dim TempHex As String
  Dim CharToEncode As Long
  Dim TempAnsShort As String

  CurChr = 1

  Do Until CurChr - 1 = Len(StringToEncode)
    CharToEncode = Asc(Mid(StringToEncode, CurChr, 1))
' http://www.utf8-chartable.de/unicode-utf8-table.pl?start=1024
' as per https://en.wikipedia.org/wiki/UTF-8 specification the engoding is as follows

    Select Case CharToEncode
'   7   U+0000 U+007F 1 0xxxxxxx
      Case 48 To 57, 65 To 90, 97 To 122
        TempAns = TempAns & Mid(StringToEncode, CurChr, 1)
      Case 32
        If UsePlusRatherThanHexForSpace = True Then
          TempAns = TempAns & "+"
        Else
          TempAns = TempAns & "%" & Hex(32)
        End If
      Case 0 To &H7F
            TempAns = TempAns + "%" + Hex(CharToEncode And &H7F)
      Case &H80 To &H7FF
'   11  U+0080 U+07FF 2 110xxxxx 10xxxxxx
' The magic is in offset calculation... there are different offsets between UTF-8 and Windows character maps
' offset 192 = &HC0 = 1100 0000 b  added to start of UTF-8 cyrillic char map at &H410
          CharToEncode = CharToEncode - 192 + &H410
          TempAnsShort = "%" & Right("0" & Hex((CharToEncode And &H3F) Or &H80), 2)
          TempAnsShort = "%" & Right("0" & Hex(((CharToEncode \ &H40) And &H1F) Or &HC0), 2) & TempAnsShort
          TempAns = TempAns + TempAnsShort

'' debug and development version
''          CharToEncode = CharToEncode - 192 + &H410
''          TempChr = (CharToEncode And &H3F) Or &H80
''          TempHex = Hex(TempChr)
''          TempAnsShort = "%" & Right("0" & TempHex, 2)
''          TempChr = ((CharToEncode And &H7C0) / &H40) Or &HC0
''          TempChr = ((CharToEncode \ &H40) And &H1F) Or &HC0
''          TempHex = Hex(TempChr)
''          TempAnsShort = "%" & Right("0" & TempHex, 2) & TempAnsShort
''          TempAns = TempAns + TempAnsShort

      Case &H800 To &HFFFF
'   16 U+0800 U+FFFF 3 1110xxxx 10xxxxxx 10xxxxxx
' not tested . Doesnot match Case condition... very strange
        MsgBox ("Char to encode  matched U+0800 U+FFFF: " & CharToEncode & " = &H" & Hex(CharToEncode))
''          CharToEncode = CharToEncode - 192 + &H410
          TempAnsShort = "%" & Right("0" & Hex((CharToEncode And &H3F) Or &H80), 2)
          TempAnsShort = "%" & Right("0" & Hex(((CharToEncode \ &H40) And &H3F) Or &H80), 2) & TempAnsShort
          TempAnsShort = "%" & Right("0" & Hex(((CharToEncode \ &H1000) And &HF) Or &HE0), 2) & TempAnsShort
          TempAns = TempAns + TempAnsShort

      Case &H10000 To &H1FFFFF
'   21 U+10000 U+1FFFFF 4 11110xxx 10xxxxxx 10xxxxxx 10xxxxxx
''        MsgBox ("Char to encode  matched &H10000 &H1FFFFF: " & CharToEncode & " = &H" & Hex(CharToEncode))
' sample offset. tobe verified
          CharToEncode = CharToEncode - 192 + &H410
          TempAnsShort = "%" & Right("0" & Hex((CharToEncode And &H3F) Or &H80), 2)
          TempAnsShort = "%" & Right("0" & Hex(((CharToEncode \ &H40) And &H3F) Or &H80), 2) & TempAnsShort
          TempAnsShort = "%" & Right("0" & Hex(((CharToEncode \ &H1000) And &H3F) Or &H80), 2) & TempAnsShort
          TempAnsShort = "%" & Right("0" & Hex(((CharToEncode \ &H40000) And &H7) Or &HF0), 2) & TempAnsShort
          TempAns = TempAns + TempAnsShort

      Case &H200000 To &H3FFFFFF
'   26  U+200000 U+3FFFFFF 5 111110xx 10xxxxxx 10xxxxxx 10xxxxxx 10xxxxxx
''        MsgBox ("Char to encode  matched U+200000 U+3FFFFFF: " & CharToEncode & " = &H" & Hex(CharToEncode))
' sample offset. tobe verified
          CharToEncode = CharToEncode - 192 + &H410
          TempAnsShort = "%" & Right("0" & Hex((CharToEncode And &H3F) Or &H80), 2)
          TempAnsShort = "%" & Right("0" & Hex(((CharToEncode \ &H40) And &H3F) Or &H80), 2) & TempAnsShort
          TempAnsShort = "%" & Right("0" & Hex(((CharToEncode \ &H1000) And &H3F) Or &H80), 2) & TempAnsShort
          TempAnsShort = "%" & Right("0" & Hex(((CharToEncode \ &H40000) And &H3F) Or &H80), 2) & TempAnsShort
          TempAnsShort = "%" & Right("0" & Hex(((CharToEncode \ &H1000000) And &H3) Or &HF8), 2) & TempAnsShort
          TempAns = TempAns + TempAnsShort

      Case &H4000000 To &H7FFFFFFF
'   31  U+4000000 U+7FFFFFFF 6 1111110x 10xxxxxx 10xxxxxx 10xxxxxx 10xxxxxx 10xxxxxx
''        MsgBox ("Char to encode  matched U+4000000 U+7FFFFFFF: " & CharToEncode & " = &H" & Hex(CharToEncode))
' sample offset. tobe verified
          CharToEncode = CharToEncode - 192 + &H410
          TempAnsShort = "%" & Right("0" & Hex((CharToEncode And &H3F) Or &H80), 2)
          TempAnsShort = "%" & Right("0" & Hex(((CharToEncode \ &H40) And &H3F) Or &H80), 2) & TempAnsShort
          TempAnsShort = "%" & Right("0" & Hex(((CharToEncode \ &H1000) And &H3F) Or &H80), 2) & TempAnsShort
          TempAnsShort = "%" & Right("0" & Hex(((CharToEncode \ &H40000) And &H3F) Or &H80), 2) & TempAnsShort
          TempAnsShort = "%" & Right("0" & Hex(((CharToEncode \ &H1000000) And &H3F) Or &H80), 2) & TempAnsShort
          TempAnsShort = "%" & Right("0" & Hex(((CharToEncode \ &H40000000) And &H1) Or &HFC), 2) & TempAnsShort
          TempAns = TempAns + TempAnsShort

      Case Else
' somethig else
' to be developped
        MsgBox ("Char to encode not matched: " & CharToEncode & " = &H" & Hex(CharToEncode))

    End Select

    CurChr = CurChr + 1
  Loop

  UTF8Encode = TempAns
End Function

Good luck!

Could not find a base address that matches scheme https for the endpoint with binding WebHttpBinding. Registered base address schemes are [http]

In the endpoint tag you need to include the property address=""

<endpoint address="" binding="webHttpBinding" bindingConfiguration="SecureBasicRest" behaviorConfiguration="svcEndpoint" name="webHttp" contract="SvcContract.Authenticate" />

Clicking at coordinates without identifying element

I used the Actions Class like many listed above, but what I found helpful was if I need find a relative position from the element I used Firefox Add-On Measurit to get the relative coordinates. For example:

        IWebDriver driver = new FirefoxDriver();
        driver.Url = @"https://scm.commerceinterface.com/accounts/login/?next=/remittance_center/";
        var target = driver.FindElement(By.Id("loginAsEU"));
        Actions builder = new Actions(driver);            
        builder.MoveToElement(target , -375  , -436).Click().Build().Perform();

I got the -375, -436 from clicking on an element and then dragging backwards until I reached the point I needed to click. The coordinates that MeasureIT said I just subtracted. In my example above, the only element I had on the page that was clickable was the "loginAsEu" link. So I started from there.

Python 3: ImportError "No Module named Setuptools"

The PyPA recommended tool for installing and managing Python packages is pip. pip is included with Python 3.4 (PEP 453), but for older versions here's how to install it (on Windows):

Download https://bootstrap.pypa.io/get-pip.py

>c:\Python33\python.exe get-pip.py
Downloading/unpacking pip
Downloading/unpacking setuptools
Installing collected packages: pip, setuptools
Successfully installed pip setuptools
Cleaning up...

>c:\Python33\Scripts\pip.exe install pymysql
Downloading/unpacking pymysql
Installing collected packages: pymysql
Successfully installed pymysql
Cleaning up...

Should ol/ul be inside <p> or outside?

actually you should only put in-line elements inside the p, so in your case ol is better outside

How do I remove an object from an array with JavaScript?

  //K.I.S.S. method
  //(the setup/comments is/are longer than the code)
  //cards is a two dimensional array object
  //  has an array object with 4 elements at each first dimensional index
  //var cards = new Array()
  //cards[cards.length] = new Array(name, colors, cost, type)
  //Can be constructed with Associated arrays, modify code as needed.
  //my test array has 60 'cards' in it
  //  15 'cards' repeated 4 times each
  //  groups were not sorted prior to execution
  //  (I had 4 groups starting with 'U' before the first 'A')
  //Should work with any dimensionality as long as first
  //index controls sort order

  //sort and remove duplicates
  //Algorithm:
  //  While same name side by side, remove higher entry;
  //  assumes 'cards' with same name have same other data
  //  (otherwise use cards[i-1] === cards[i] to compare array objects).
  //Tested on IE9 and FireFox (multiple version #s from 31 up).
  //Also tested by importing array data from 5MB text file.
  //Quick execution
  cards.sort()
  for (i=1; i<cards.length-1; i++){
    while (cards[i-1][0] == cards[i][0]){
       cards.splice(i,1)
    }
  }

Can jQuery check whether input content has changed?

I don't think there's a 'simple' solution. You'll probably need to use both the events onKeyUp and onChange so that you also catch when changes are made with the mouse. Every time your code is called you can store the value you've 'seen' on this.seenValue attached right to the field. This should make a little easier.

Concatenating multiple text files into a single file in Bash

The Windows shell command type can do this:

type *.txt >outputfile

Type type command also writes file names to stderr, which are not captured by the > redirect operator (but will show up on the console).

Trigger a Travis-CI rebuild without pushing a commit?

I have found another way of forcing re-run CI builds and other triggers:

  1. Run git commit --amend --no-edit without any changes. This will recreate the last commit in the current branch.
  2. git push --force-with-lease origin pr-branch.

Cannot install packages inside docker Ubuntu image

From the docs in May 2017 2018 2019 2020

Always combine RUN apt-get update with apt-get install in the same RUN statement, for example

RUN apt-get update && apt-get install -y package-bar

(...)

Using apt-get update alone in a RUN statement causes caching issues and subsequent apt-get install instructions fail.

(...)

Using RUN apt-get update && apt-get install -y ensures your Dockerfile installs the latest package versions with no further coding or manual intervention. This technique is known as “cache busting”.

Round to at most 2 decimal places (only if necessary)

Use Math.round() :

Math.round(num * 100) / 100

Or to be more specific and to ensure things like 1.005 round correctly, use Number.EPSILON :

Math.round((num + Number.EPSILON) * 100) / 100

Get last n lines of a file, similar to tail

Although this isn't really on the efficient side with big files, this code is pretty straight-forward:

  1. It reads the file object, f.
  2. It splits the string returned using newlines, \n.
  3. It gets the array lists last indexes, using the negative sign to stand for the last indexes, and the : to get a subarray.

    def tail(f,n):
        return "\n".join(f.read().split("\n")[-n:])
    

How to create a link to a directory

Symbolic or soft link (files or directories, more flexible and self documenting)

#     Source                             Link
ln -s /home/jake/doc/test/2000/something /home/jake/xxx

Hard link (files only, less flexible and not self documenting)

#   Source                             Link
ln /home/jake/doc/test/2000/something /home/jake/xxx

More information: man ln


/home/jake/xxx is like a new directory. To avoid "is not a directory: No such file or directory" error, as @trlkly comment, use relative path in the target, that is, using the example:

  1. cd /home/jake/
  2. ln -s /home/jake/doc/test/2000/something xxx

Parse error: syntax error, unexpected T_ECHO in

Missing ; after var_dump($row)

How to determine the encoding of text?

It is, in principle, impossible to determine the encoding of a text file, in the general case. So no, there is no standard Python library to do that for you.

If you have more specific knowledge about the text file (e.g. that it is XML), there might be library functions.

Difference between _self, _top, and _parent in the anchor tag target attribute

Below is an image showing nested frames and the effect of different target values, followed by an explanation of the image.

Different target values.1

Imagine a webpage containing 3 nested <iframe> aka "frame"/"frameset". So:

  • the outermost webpage/browser is the starting context
  • the outermost webpage is the parent of frame 3
  • frame 3 is the parent of frame 2
  • frame 2 is the parent of frame 1
  • frame 1 is the innermost frame

Then target attributes have these effects:

  • If frame 1 has a link with target="_self", the link targets frame 1 (i.e. the link targets the frame containing the link (i.e. targets itself))
  • If frame 1 has a link with target="_parent", the link targets frame 2 (i.e. the link targets the parent frame)
  • If frame 1 has a link with target="_top", the link targets the initial webpage (i.e. the link targets the topmost/outermost frame; (in this case; the link skips past the grandparent frame 3))
    • If frame 2 has a link with target="_top", the link also targets the initial webpage (i.e. again, the link targets the topmost/outermost frame)
  • If any of these frames has a link with target="_blank", the link targets an auxiliary browsing context, aka a "new window"/"new tab"

Multiple definition of ... linker error

Don't define variables in headers. Put declarations in header and definitions in one of the .c files.

In config.h

extern const char *names[];

In some .c file:

const char *names[] =
    {
        "brian", "stefan", "steve"
    };

If you put a definition of a global variable in a header file, then this definition will go to every .c file that includes this header, and you will get multiple definition error because a varible may be declared multiple times but can be defined only once.

How to get the PYTHONPATH in shell?

Just write:

just write which python in your terminal and you will see the python path you are using.

Change language for bootstrap DateTimePicker

i think you have to set it in the options:

$(".form_datetime").datetimepicker({
    isRTL: false,
    format: 'dd.mm.yyyy hh:ii',
    autoclose:true,
    language: 'ru'
});

if its not working, be sure that:

$.fn.datetimepicker.dates['en'] = {
    days: ["Sunday", "Monday", "Tuesday", "Wednesday", "Thursday", "Friday", "Saturday", "Sunday"],
    daysShort: ["Sun", "Mon", "Tue", "Wed", "Thu", "Fri", "Sat", "Sun"],
    daysMin: ["Su", "Mo", "Tu", "We", "Th", "Fr", "Sa", "Su"],
    months: ["January", "February", "March", "April", "May", "June", "July", "August", "September", "October", "November", "December"],
    monthsShort: ["Jan", "Feb", "Mar", "Apr", "May", "Jun", "Jul", "Aug", "Sep", "Oct", "Nov", "Dec"],
    today: "Today"
};

is defined for 'ru'

Format a message using MessageFormat.format() in Java

For everyone that has Android problems in the string.xml, use \'\' instead of single quote.

Run git pull over all subdirectories

None of the top 5 answers worked for me, and the question talked about directories.

This worked:

for d in *; do pushd $d && git pull && popd; done

How to play or open *.mp3 or *.wav sound file in c++ program?

First of all, write the following code:

#include <Mmsystem.h>
#include <mciapi.h>
//these two headers are already included in the <Windows.h> header
#pragma comment(lib, "Winmm.lib")

To open *.mp3:

mciSendString("open \"*.mp3\" type mpegvideo alias mp3", NULL, 0, NULL);

To play *.mp3:

mciSendString("play mp3", NULL, 0, NULL);

To play and wait until the *.mp3 has finished playing:

mciSendString("play mp3 wait", NULL, 0, NULL);

To replay (play again from start) the *.mp3:

mciSendString("play mp3 from 0", NULL, 0, NULL);

To replay and wait until the *.mp3 has finished playing:

mciSendString("play mp3 from 0 wait", NULL, 0, NULL);

To play the *.mp3 and replay it every time it ends like a loop:

mciSendString("play mp3 repeat", NULL, 0, NULL);

If you want to do something when the *.mp3 has finished playing, then you need to RegisterClassEx by the WNDCLASSEX structure, CreateWindowEx and process it's messages with the GetMessage, TranslateMessage and DispatchMessage functions in a while loop and call:

mciSendString("play mp3 notify", NULL, 0, hwnd); //hwnd is an handle to the window returned from CreateWindowEx. If this doesn't work, then replace the hwnd with MAKELONG(hwnd, 0).

In the window procedure, add the case MM_MCINOTIFY: The code in there will be executed when the mp3 has finished playing.

But if you program a Console Application and you don't deal with windows, then you can CreateThread in suspend state by specifying the CREATE_SUSPENDED flag in the dwCreationFlags parameter and keep the return value in a static variable and call it whatever you want. For instance, I call it mp3. The type of this static variable is HANDLE of course.

Here is the ThreadProc for the lpStartAddress of this thread:

DWORD WINAPI MP3Proc(_In_ LPVOID lpParameter) //lpParameter can be a pointer to a structure that store data that you cannot access outside of this function. You can prepare this structure before `CreateThread` and give it's address in the `lpParameter`
{
    Data *data = (Data*)lpParameter; //If you call this structure Data, but you can call it whatever you want.
    while (true)
    {
        mciSendString("play mp3 from 0 wait", NULL, 0, NULL);
        //Do here what you want to do when the mp3 playback is over
        SuspendThread(GetCurrentThread()); //or the handle of this thread that you keep in a static variable instead
    }
}

All what you have to do now is to ResumeThread(mp3); every time you want to replay your mp3 and something will happen every time it finishes.

You can #define play_my_mp3 ResumeThread(mp3); to make your code more readable.

Of course you can remove the while (true), SuspendThread and the from 0 codes, if you want to play your mp3 file only once and do whatever you want when it is over.

If you only remove the SuspendThread call, then the sound will play over and over again and do something whenever it is over. This is equivalent to:

mciSendString("play mp3 repeat notify", NULL, 0, hwnd); //or MAKELONG(hwnd, 0) instead

in windows.

To pause the *.mp3 in middle:

mciSendString("pause mp3", NULL, 0, NULL);

and to resume it:

mciSendString("resume mp3", NULL, 0, NULL);

To stop it in middle:

mciSendString("stop mp3", NULL, 0, NULL);

Note that you cannot resume a sound that has been stopped, but only paused, but you can replay it by carrying out the play command. When you're done playing this *.mp3, don't forget to:

mciSendString("close mp3", NULL, 0, NULL);

All these actions also apply to (work with) wave files too, but with wave files, you can use "waveaudio" instead of "mpegvideo". Also you can just play them directly without opening them:

PlaySound("*.wav", GetModuleHandle(NULL), SND_FILENAME);

If you don't want to specify an handle to a module:

sndPlaySound("*.wav", SND_FILENAME);

If you don't want to wait until the playback is over:

PlaySound("*.wav", GetModuleHandle(NULL), SND_FILENAME | SND_ASYNC);
//or
sndPlaySound("*.wav", SND_FILENAME | SND_ASYNC);

To play the wave file over and over again:

PlaySound("*.wav", GetModuleHandle(NULL), SND_FILENAME | SND_ASYNC | SND_LOOP);
//or
sndPlaySound("*.wav", SND_FILENAME | SND_ASYNC | SND_LOOP);

Note that you must specify both the SND_ASYNC and SND_LOOP flags, because you never going to wait until a sound, that repeats itself countless times, is over!

Also you can fopen the wave file and copy all it's bytes to a buffer (an enormous/huge (very big) array of bytes) with the fread function and then:

PlaySound(buffer, GetModuleHandle(NULL), SND_MEMORY);
//or
PlaySound(buffer, GetModuleHandle(NULL), SND_MEMORY | SND_ASYNC);
//or
PlaySound(buffer, GetModuleHandle(NULL), SND_MEMORY | SND_ASYNC | SND_LOOP);
//or
sndPlaySound(buffer, SND_MEMORY);
//or
sndPlaySound(buffer, SND_MEMORY | SND_ASYNC);
//or
sndPlaySound(buffer, SND_MEMORY | SND_ASYNC | SND_LOOP);

Either OpenFile or CreateFile or CreateFile2 and either ReadFile or ReadFileEx functions can be used instead of fopen and fread functions.

Hope this fully answers perfectly your question.

VBA general way for pulling data out of SAP

This all depends on what sort of access you have to your SAP system. An ABAP program that exports the data and/or an RFC that your macro can call to directly get the data or have SAP create the file is probably best.

However as a general rule people looking for this sort of answer are looking for an immediate solution that does not require their IT department to spend months customizing their SAP system.

In that case you probably want to use SAP GUI Scripting. SAP GUI scripting allows you to automate the Windows SAP GUI in much the same way as you automate Excel. In fact you can call the SAP GUI directly from an Excel macro. Read up more on it here. The SAP GUI has a macro recording tool much like Excel does. It records macros in VBScript which is nearly identical to Excel VBA and can usually be copied and pasted into an Excel macro directly.

Example Code

Here is a simple example based on a SAP system I have access to.

Public Sub SimpleSAPExport()
  Set SapGuiAuto  = GetObject("SAPGUI") 'Get the SAP GUI Scripting object
  Set SAPApp = SapGuiAuto.GetScriptingEngine 'Get the currently running SAP GUI 
  Set SAPCon = SAPApp.Children(0) 'Get the first system that is currently connected
  Set session = SAPCon.Children(0) 'Get the first session (window) on that connection

  'Start the transaction to view a table
  session.StartTransaction "SE16"

  'Select table T001
  session.findById("wnd[0]/usr/ctxtDATABROWSE-TABLENAME").Text = "T001"
  session.findById("wnd[0]/tbar[1]/btn[7]").Press

  'Set our selection criteria
  session.findById("wnd[0]/usr/txtMAX_SEL").text = "2"
  session.findById("wnd[0]/tbar[1]/btn[8]").press

  'Click the export to file button
  session.findById("wnd[0]/tbar[1]/btn[45]").press

  'Choose the export format
  session.findById("wnd[1]/usr/subSUBSCREEN_STEPLOOP:SAPLSPO5:0150/sub:SAPLSPO5:0150/radSPOPLI-SELFLAG[1,0]").select
  session.findById("wnd[1]/tbar[0]/btn[0]").press

  'Choose the export filename
  session.findById("wnd[1]/usr/ctxtDY_FILENAME").text = "test.txt"
  session.findById("wnd[1]/usr/ctxtDY_PATH").text = "C:\Temp\"

  'Export the file
  session.findById("wnd[1]/tbar[0]/btn[0]").press
End Sub

Script Recording

To help find the names of elements such aswnd[1]/tbar[0]/btn[0] you can use script recording. Click the customize local layout button, it probably looks a bit like this: Customize Local Layout
Then find the Script Recording and Playback menu item.
Script Recording and Playback
Within that the More button allows you to see/change the file that the VB Script is recorded to. The output format is a bit messy, it records things like selecting text, clicking inside a text field, etc.

Edit: Early and Late binding

The provided script should work if copied directly into a VBA macro. It uses late binding, the line Set SapGuiAuto = GetObject("SAPGUI") defines the SapGuiAuto object.

If however you want to use early binding so that your VBA editor might show the properties and methods of the objects you are using, you need to add a reference to sapfewse.ocx in the SAP GUI installation folder.

Reset AutoIncrement in SQL Server after Delete

I figured it out. It's:

 DBCC CHECKIDENT ('tablename', RESEED, newseed)

How do you detect Credit card type based on number?

I use https://github.com/bendrucker/creditcards-types/ to detect the credit card type from number. One issue I ran into is discover test number 6011 1111 1111 1117

from https://www.cybersource.com/developers/other_resources/quick_references/test_cc_numbers/ we can see it is a discover number because it starts by 6011. But the result I get from the creditcards-types is "Maestro". I opened the issue to the author. He replied me very soon and provide this pdf doc https://www.discovernetwork.com/downloads/IPP_VAR_Compliance.pdf From the doc we can see clearly that 6011 1111 1111 1117 does not fall into the range of discover credit card.

GIT_DISCOVERY_ACROSS_FILESYSTEM not set

The problem is you are not in the correct directory. A simple fix in Jupyter is to do the following command:

  1. Move to the GitHub directory for your installation
  2. Run the GitHub command

Here is an example command to use in Jupyter:

%%bash
cd /home/ec2-user/ml_volume/GitHub_BMM
git show

Note you need to do the commands in the same cell.

how to parse xml to java object?

JAXB is a reliable choice as it does xml to java classes mapping smoothely. But there are other frameworks available, here is one such:

https://code.google.com/p/xmappr/

Fill remaining vertical space with CSS using display:flex

Make it simple : DEMO

_x000D_
_x000D_
section {_x000D_
  display: flex;_x000D_
  flex-flow: column;_x000D_
  height: 300px;_x000D_
}_x000D_
_x000D_
header {_x000D_
  background: tomato;_x000D_
  /* no flex rules, it will grow */_x000D_
}_x000D_
_x000D_
div {_x000D_
  flex: 1;  /* 1 and it will fill whole space left if no flex value are set to other children*/_x000D_
  background: gold;_x000D_
  overflow: auto;_x000D_
}_x000D_
_x000D_
footer {_x000D_
  background: lightgreen;_x000D_
  min-height: 60px;  /* min-height has its purpose :) , unless you meant height*/_x000D_
}
_x000D_
<section>_x000D_
  <header>_x000D_
    header: sized to content_x000D_
    <br/>(but is it really?)_x000D_
  </header>_x000D_
  <div>_x000D_
    main content: fills remaining space<br> x_x000D_
    <br>x<br>x<br>x<br>x<br>x<br>x<br>x<br>x<br>x<br>_x000D_
    <!-- uncomment to see it break -->_x000D_
    x<br>x<br>x<br>x<br>x<br>x<br>x<br>x<br>x<br> x_x000D_
    <br>x<br>x<br>x<br>x<br>x<br>x<br>x<br>x<br> x_x000D_
    <br>x<br>x<br>x<br>x<br>x<br>x<br>x<br>x<br> x_x000D_
    <br>x<br>x<br>x<br>x<br>x<br>x<br>x<br>x<br>_x000D_
    <!-- -->_x000D_
  </div>_x000D_
  <footer>_x000D_
    footer: fixed height in px_x000D_
  </footer>_x000D_
</section>
_x000D_
_x000D_
_x000D_

Full screen version

_x000D_
_x000D_
section {_x000D_
  display: flex;_x000D_
  flex-flow: column;_x000D_
  height: 100vh;_x000D_
}_x000D_
_x000D_
header {_x000D_
  background: tomato;_x000D_
  /* no flex rules, it will grow */_x000D_
}_x000D_
_x000D_
div {_x000D_
  flex: 1;_x000D_
  /* 1 and it will fill whole space left if no flex value are set to other children*/_x000D_
  background: gold;_x000D_
  overflow: auto;_x000D_
}_x000D_
_x000D_
footer {_x000D_
  background: lightgreen;_x000D_
  min-height: 60px;_x000D_
  /* min-height has its purpose :) , unless you meant height*/_x000D_
}_x000D_
_x000D_
body {_x000D_
  margin: 0;_x000D_
}
_x000D_
<section>_x000D_
  <header>_x000D_
    header: sized to content_x000D_
    <br/>(but is it really?)_x000D_
  </header>_x000D_
  <div>_x000D_
    main content: fills remaining space<br> x_x000D_
    <br>x<br>x<br>x<br>x<br>x<br>x<br>x<br>x<br>x<br>_x000D_
    <!-- uncomment to see it break -->_x000D_
    x<br>x<br>x<br>x<br>x<br>x<br>x<br>x<br>x<br> x_x000D_
    <br>x<br>x<br>x<br>x<br>x<br>x<br>x<br>x<br> x_x000D_
    <br>x<br>x<br>x<br>x<br>x<br>x<br>x<br>x<br> x_x000D_
    <br>x<br>x<br>x<br>x<br>x<br>x<br>x<br>x<br>_x000D_
    <!-- -->_x000D_
  </div>_x000D_
  <footer>_x000D_
    footer: fixed height in px_x000D_
  </footer>_x000D_
</section>
_x000D_
_x000D_
_x000D_

Div 100% height works on Firefox but not in IE

I think "works fine in Firefox" is in the Quirks mode rendering only. In the Standard mode rendering, that might not work fine in Firefox too.

percentage depends on "containing block", instead of viewport.

CSS Specification says

The percentage is calculated with respect to the height of the generated box's containing block. If the height of the containing block is not specified explicitly (i.e., it depends on content height), and this element is not absolutely positioned, the value computes to 'auto'.

so

#container { height: auto; }
#container #mainContentsWrapper { height: n%; }
#container #sidebarWrapper { height: n%; }

means

#container { height: auto; }
#container #mainContentsWrapper { height: auto; }
#container #sidebarWrapper { height: auto; }

To stretch to 100% height of viewport, you need to specify the height of the containing block (in this case, it's #container). Moreover, you also need to specify the height to body and html, because initial Containing Block is "UA-dependent".

All you need is...

html, body { height:100%; }
#container { height:100%; }

Undo git stash pop that results in merge conflict

As it turns out, Git is smart enough not to drop a stash if it doesn't apply cleanly. I was able to get to the desired state with the following steps:

  1. To unstage the merge conflicts: git reset HEAD . (note the trailing dot)
  2. To save the conflicted merge (just in case): git stash
  3. To return to master: git checkout master
  4. To pull latest changes: git fetch upstream; git merge upstream/master
  5. To correct my new branch: git checkout new-branch; git rebase master
  6. To apply the correct stashed changes (now 2nd on the stack): git stash apply stash@{1}

Allow access permission to write in Program Files of Windows 7

I was looking for answers. I found only one.

None of these work for me. I am not trying to write temporary files, unless this is defined as nonsystem files. Although I am designated the admin on my user profile, with full admin rights indicated in the UAC, I cannot write to program files or windows. This is very irritating.

I try to save an image found online directly to the windows/web/wallpaper folder and it won't let me. Instead, I must save it to my desktop (I REFUSE to navigate to "my documents/pictures/etc" as I refuse to USE such folders, I have my own directory tree thank you) then, from the desktop, cut and paste it to the windows/web/wallpaper folder. And you are telling me I should do that and smile? As an admin user, I SHOULD be able to save directly to its destination folder. My permissions in drive properties/security and in directory properties/security say I can write, but I can't. Not to program files, program files (86) and windows.

How about saving a file I just modified for a game in Program Files (86) (name of game) folder. It won't let me. I open the file to modify it, I can't save it without first either saving it to desktop etc as above, or opening the program which is used for modifying the file first as admin, which means first navigating all the way over to another part of the directory tree where I store those user mod programs, then within the program selecting to open file and navigate again to the file I could have just clicked on to modify in the first place from my projects folder, only to discover that this won't work either! It saves the file, but the file cannot be located. It is there, but invisible. The only solution is to save to desktop as above.

I shouldn't have to do all this as an admin user. However, if I use the true admin account all works fine. But I don't want to use the real admin account. I want to use a user account with admin rights. It says I have admin rights, but I don't.

And, finally, I refuse to store my portables in %appdata%. This is not how I wish to navigate through my directory tree. My personal installations which I use as portables are stored in the directory I create as a navigation preference.

So, here is the tried and true answer I have found:

From what I have seen so far.... unless one uses the real admin account, these permissions just aren't ever really available to any other user with admin privileges in the Windows Vista and Windows 7 OS's. While it was simple to set admin privileges in Windows XP, later versions have taken this away for all but those who can comfortably hack around.

What are the different types of keys in RDBMS?

(I) Super Key – An attribute or a combination of attribute that is used to identify the records uniquely is known as Super Key. A table can have many Super Keys.

E.g. of Super Key

  1. ID
  2. ID, Name
  3. ID, Address
  4. ID, Department_ID
  5. ID, Salary
  6. Name, Address
  7. Name, Address, Department_ID

So on as any combination which can identify the records uniquely will be a Super Key.

(II) Candidate Key – It can be defined as minimal Super Key or irreducible Super Key. In other words an attribute or a combination of attribute that identifies the record uniquely but none of its proper subsets can identify the records uniquely.

E.g. of Candidate Key

  1. ID
  2. Name, Address

For above table we have only two Candidate Keys (i.e. Irreducible Super Key) used to identify the records from the table uniquely. ID Key can identify the record uniquely and similarly combination of Name and Address can identify the record uniquely, but neither Name nor Address can be used to identify the records uniquely as it might be possible that we have two employees with similar name or two employees from the same house.

(III) Primary Key – A Candidate Key that is used by the database designer for unique identification of each row in a table is known as Primary Key. A Primary Key can consist of one or more attributes of a table.

E.g. of Primary Key - Database designer can use one of the Candidate Key as a Primary Key. In this case we have “ID” and “Name, Address” as Candidate Key, we will consider “ID” Key as a Primary Key as the other key is the combination of more than one attribute.

(IV) Foreign Key – A foreign key is an attribute or combination of attribute in one base table that points to the candidate key (generally it is the primary key) of another table. The purpose of the foreign key is to ensure referential integrity of the data i.e. only values that are supposed to appear in the database are permitted.

E.g. of Foreign Key – Let consider we have another table i.e. Department Table with Attributes “Department_ID”, “Department_Name”, “Manager_ID”, ”Location_ID” with Department_ID as an Primary Key. Now the Department_ID attribute of Employee Table (dependent or child table) can be defined as the Foreign Key as it can reference to the Department_ID attribute of the Departments table (the referenced or parent table), a Foreign Key value must match an existing value in the parent table or be NULL.

(V) Composite Key – If we use multiple attributes to create a Primary Key then that Primary Key is called Composite Key (also called a Compound Key or Concatenated Key).

E.g. of Composite Key, if we have used “Name, Address” as a Primary Key then it will be our Composite Key.

(VI) Alternate Key – Alternate Key can be any of the Candidate Keys except for the Primary Key.

E.g. of Alternate Key is “Name, Address” as it is the only other Candidate Key which is not a Primary Key.

(VII) Secondary Key – The attributes that are not even the Super Key but can be still used for identification of records (not unique) are known as Secondary Key.

E.g. of Secondary Key can be Name, Address, Salary, Department_ID etc. as they can identify the records but they might not be unique.

Query to list number of records in each table in a database

This sql script gives the schema, table name and row count of each table in a database selected:

SELECT SCHEMA_NAME(schema_id) AS [SchemaName],
[Tables].name AS [TableName],
SUM([Partitions].[rows]) AS [TotalRowCount]
FROM sys.tables AS [Tables]
JOIN sys.partitions AS [Partitions]
ON [Tables].[object_id] = [Partitions].[object_id]
AND [Partitions].index_id IN ( 0, 1 )
-- WHERE [Tables].name = N'name of the table'
GROUP BY SCHEMA_NAME(schema_id), [Tables].name
order by [TotalRowCount] desc

Ref: https://blog.sqlauthority.com/2017/05/24/sql-server-find-row-count-every-table-database-efficiently/

Another way of doing this:

SELECT  o.NAME TABLENAME,
  i.rowcnt 
FROM sysindexes AS i
  INNER JOIN sysobjects AS o ON i.id = o.id 
WHERE i.indid < 2  AND OBJECTPROPERTY(o.id, 'IsMSShipped') = 0
ORDER BY i.rowcnt desc

ffmpeg usage to encode a video to H264 codec format

"C:\Program Files (x86)\ffmpegX86shared\bin\ffmpeg.exe" -y -i "C:\testfile.ts" -an -vcodec libx264 -g 75 -keyint_min 12 -vb 4000k -vprofile high -level 40 -s 1920x1080 -y -threads 0 -r 25 "C:\testfile.h264"

The above worked for me on a Windows machine using a FFmpeg Win32 shared build by Kyle Schwarz. The build was compiled on: Feb 22 2013, at: 01:09:53

Note that -an defines that audio should be skipped.

window.onload vs document.onload

In Chrome, window.onload is different from <body onload="">, whereas they are the same in both Firefox(version 35.0) and IE (version 11).

You could explore that by the following snippet:

<!DOCTYPE html>
<html xmlns="http://www.w3.org/1999/xhtml">
    <head>
        <meta http-equiv="Content-Type" content="text/html; charset=utf-8" />
        <!--import css here-->
        <!--import js scripts here-->

        <script language="javascript">

            function bodyOnloadHandler() {
                console.log("body onload");
            }

            window.onload = function(e) {
                console.log("window loaded");
            };
        </script>
    </head>

    <body onload="bodyOnloadHandler()">

        Page contents go here.

    </body>
</html>

And you will see both "window loaded"(which comes firstly) and "body onload" in Chrome console. However, you will see just "body onload" in Firefox and IE. If you run "window.onload.toString()" in the consoles of IE & FF, you will see:

"function onload(event) { bodyOnloadHandler() }"

which means that the assignment "window.onload = function(e)..." is overwritten.

How to take a first character from the string

Try this:

Dim s = "RAJAN"
Dim firstChar = s(0)

You can even do this:

Dim firstChar = "RAJAN"(0)

Oracle PL/SQL - How to create a simple array variable?

Another solution is to use an Oracle Collection as a Hashmap:

declare 
-- create a type for your "Array" - it can be of any kind, record might be useful
  type hash_map is table of varchar2(1000) index by varchar2(30);
  my_hmap hash_map ;
-- i will be your iterator: it must be of the index's type
  i varchar2(30);
begin
  my_hmap('a') := 'apple';
  my_hmap('b') := 'box';
  my_hmap('c') := 'crow';
-- then how you use it:

  dbms_output.put_line (my_hmap('c')) ;

-- or to loop on every element - it's a "collection"
  i := my_hmap.FIRST;

  while (i is not null)  loop     
    dbms_output.put_line(my_hmap(i));      
    i := my_hmap.NEXT(i);
  end loop;

end;

summing two columns in a pandas dataframe

If "budget" has any NaN values but you don't want it to sum to NaN then try:

def fun (b, a):
    if math.isnan(b):
        return a
    else:
        return b + a

f = np.vectorize(fun, otypes=[float])

df['variance'] = f(df['budget'], df_Lp['actual'])

how to show calendar on text box click in html

try to use jquery-ui

<script src="http://code.jquery.com/ui/1.10.1/jquery-ui.js"></script>

<script>   
    $(function() {
         $( "#calendar" ).datepicker();   
    }); 
</script>

<p>Calendar: <input type="text" id="calendar" /></p>

more

How to listen for changes to a MongoDB collection?

MongoDB version 3.6 now includes change streams which is essentially an API on top of the OpLog allowing for trigger/notification-like use cases.

Here is a link to a Java example: http://mongodb.github.io/mongo-java-driver/3.6/driver/tutorials/change-streams/

A NodeJS example might look something like:

 var MongoClient = require('mongodb').MongoClient;
    MongoClient.connect("mongodb://localhost:22000/MyStore?readConcern=majority")
     .then(function(client){
       let db = client.db('MyStore')

       let change_streams = db.collection('products').watch()
          change_streams.on('change', function(change){
            console.log(JSON.stringify(change));
          });
      });

Saving excel worksheet to CSV files with filename+worksheet name using VB

Best way to find out is to record the macro and perform the exact steps and see what VBA code it generates. you can then go and replace the bits you want to make generic (i.e. file names and stuff)

Background color not showing in print preview

The best solution for this if you are using bootstrap so just do one thing remove @media print {} all code inside this. and enable background graphics from more settings while taking print preview.

How can I run MongoDB as a Windows service?

not only --install,

also need --dbpath and --logpath

and after reboot OS you need to delete "mongod.lock" manually

How to create permanent PowerShell Aliases

to create the profile1.psl file, type in the following command:

new-item $PROFILE.CurrentUserAllHosts -ItemType file -Force

to access the file, type in the next command:

ise $PROFILE.CurrentUserAllHosts

note if you haven't done this before, you will see that you will not be able to run the script because of your execution policy, which you need to change to Unrestricted from Restricted (default).

to do that close the script and then type this command:

Set-ExecutionPolicy -Scope CurrentUser

then:

RemoteSigned

then this command again:

ise $PROFILE.CurrentUserAllHosts

then finally type your aliases in the script, save it, and they should run every time you run powershell, even after restarting your computer.

Make a simple fade in animation in Swift?

0x7ffffff's answer is ok and definitely exhaustive.

As a plus, I suggest you to make an UIView extension, in this way:

public extension UIView {

  /**
  Fade in a view with a duration

  - parameter duration: custom animation duration
  */
  func fadeIn(duration duration: NSTimeInterval = 1.0) {
    UIView.animateWithDuration(duration, animations: {
        self.alpha = 1.0
    })
  }

  /**
  Fade out a view with a duration

  - parameter duration: custom animation duration
  */
  func fadeOut(duration duration: NSTimeInterval = 1.0) {
    UIView.animateWithDuration(duration, animations: {
        self.alpha = 0.0
    })
  }

}

Swift-3

/// Fade in a view with a duration
/// 
/// Parameter duration: custom animation duration
func fadeIn(withDuration duration: TimeInterval = 1.0) {
    UIView.animate(withDuration: duration, animations: {
        self.alpha = 1.0
    })
}

/// Fade out a view with a duration
///
/// - Parameter duration: custom animation duration
func fadeOut(withDuration duration: TimeInterval = 1.0) {
    UIView.animate(withDuration: duration, animations: {
        self.alpha = 0.0
    })
}

In this way you can do this wherever in your code:

let newImage = UIImage(named: "")
newImage.alpha = 0 // or newImage.fadeOut(duration: 0.0)
self.view.addSubview(newImage)
... 
newImage.fadeIn()

Code reuse is important!

Calculate days between two Dates in Java 8

Everyone is saying to use ChronoUnit.DAYS.between but that just delegates to another method you could call yourself. So you could also do firstDate.until(secondDate, ChronoUnit.DAYS).

The docs for both actually mention both approaches and say to use whichever one is more readable.

Hadoop/Hive : Loading data from .csv on a local machine

Let me work you through the following simple steps:

Steps:

First, create a table on hive using the field names in your csv file. Lets say for example, your csv file contains three fields (id, name, salary) and you want to create a table in hive called "staff". Use the below code to create the table in hive.

hive> CREATE TABLE Staff (id int, name string, salary double) row format delimited fields terminated by ',';

Second, now that your table is created in hive, let us load the data in your csv file to the "staff" table on hive.

hive>  LOAD DATA LOCAL INPATH '/home/yourcsvfile.csv' OVERWRITE INTO TABLE Staff;

Lastly, display the contents of your "Staff" table on hive to check if the data were successfully loaded

hive> SELECT * FROM Staff;

Thanks.

Lining up labels with radio buttons in bootstrap

If you add the 'radio inline' class to the control label in the solution provided by user1938475 it should line up correctly with the other labels. Or if you're only using 'radio' like your 2nd example just include the 'radio' class.

<label class="radio control-label">Some label</label>

OR for 'radio inline'

<label class="radio-inline control-label">Some label</label>

Sql error on update : The UPDATE statement conflicted with the FOREIGN KEY constraint

Reason is as @MilicaMedic says. Alternative solution is disable all constraints, do the update and then enable the constraints again like this. Very useful when updating test data in test environments.

exec sp_MSforeachtable "ALTER TABLE ? NOCHECK CONSTRAINT all"

update patient set id_no='7008255601088' where id_no='8008255601088'
update patient_address set id_no='7008255601088' where id_no='8008255601088'

exec sp_MSforeachtable "ALTER TABLE ? WITH CHECK CHECK CONSTRAINT all"

Source:

https://stackoverflow.com/a/161410/3850405

Python: Fetch first 10 results from a list

list[:10]

will give you the first 10 elements of this list using slicing.

However, note, it's best not to use list as a variable identifier as it's already used by Python: list()

To find out more about these type of operations you might find this tutorial on lists helpful and the link @DarenThomas provided Explain Python's slice notation - thanks Daren)

Notepad++ Regular expression find and delete a line

If it supports standard regex...

find:
^.*#RedirectMatch Permanent.*$

replace:

Replace with nothing.

Redirecting 404 error with .htaccess via 301 for SEO etc

I came up with the solution and posted it on my blog

http://web.archive.org/web/20130310123646/http://onlinemarketingexperts.com.au/2013/01/how-to-permanently-redirect-301-all-404-missing-pages-in-htaccess/

here is the htaccess code also

RewriteEngine on
RewriteCond %{REQUEST_FILENAME} !-f
RewriteRule . / [L,R=301]

but I posted other solutions on my blog too, it depends what you need really

How to get the width and height of an android.widget.ImageView?

My answer on this question might help you:

int finalHeight, finalWidth;
final ImageView iv = (ImageView)findViewById(R.id.scaled_image);
final TextView tv = (TextView)findViewById(R.id.size_label);
ViewTreeObserver vto = iv.getViewTreeObserver();
vto.addOnPreDrawListener(new ViewTreeObserver.OnPreDrawListener() {
    public boolean onPreDraw() {
        iv.getViewTreeObserver().removeOnPreDrawListener(this);
        finalHeight = iv.getMeasuredHeight();
        finalWidth = iv.getMeasuredWidth();
        tv.setText("Height: " + finalHeight + " Width: " + finalWidth);
        return true;
    }
});

You can then add your image scaling work from within the onPreDraw() method.

What is the difference between Html.Hidden and Html.HiddenFor

The Html.Hidden creates a hidden input but you have to specify the name and all the attributes you want to give that field and value. The Html.HiddenFor creates a hidden input for the object that you pass to it, they look like this:

Html.Hidden("yourProperty",model.yourProperty);

Html.HiddenFor(m => m.yourProperty)

In this case the output is the same!

Username and password in command for git push

I used below format

git push https://username:[email protected]/file.git --all

and if your password or username contain @ replace it with %40

Why do we need to use flatMap?

flatMap transform the items emitted by an Observable into new Observables, then flattens the emissions from those into a single Observable.

Check out the scenario below where get("posts") returns an Observable that is "flattened" by flatMap.

myObservable.map(e => get("posts")).subscribe(o => console.log(o));
// this would log Observable objects to console.  

myObservable.flatMap(e => get("posts")).subscribe(o => console.log(o));
// this would log posts to console.

Why aren't programs written in Assembly more often?

Ditto most of what others have said.

In the good old days before C was invented, when the only high level languages were things like COBOL and FORTRAN, there were lots of things that just weren't possible to do without resorting to assembler. It was the only way to get the full breadth of flexibility, to be able to access all the devices, etc. But then C was invented, and almost anything that was possible in assembly was possible in C. I have written very little assembly since then.

That said, I think it is a very useful exercise for new programmers to learn to write in assembler. Not because they would actually use it much, but because then you understand what is really happening inside the computer. I've seen lots of programming errors and inefficient code from programmers who clearly have no idea what's really happening with the bits and bytes and registers.

How to get text of an input text box during onKeyPress?

So there are advantages and disadvantages to each event. The events onkeypress and onkeydown don't retrieve the latest value, and onkeypress doesn't fire for non-printable characters in some browsers. The onkeyup event doesn't detect when a key is held down for multiple characters.

This is a little hacky, but doing something like

function edValueKeyDown(input) {
    var s = input.value;

    var lblValue = document.getElementById("lblValue");
    lblValue.innerText = "The text box contains: "+s;

    //var s = $("#edValue").val();
    //$("#lblValue").text(s);    
}
<input id="edValue" type="text" onkeydown="setTimeout(edValueKeyDown, 0, this)" />

seems to handle the best of all worlds.

Call javascript from MVC controller action

It is late answer but can be useful for others. In view use ViewBag as following:

@Html.Raw("<script>" + ViewBag.DynamicScripts + "</script>")

Then from controller set this ViewBag as follows:

ViewBag.DynamicScripts = "javascriptFun()";

This will execute JavaScript function. But this function would not execute if it is ajax call. To call JavaScript function from ajax call back, return two values from controller and write success function in ajax callback as following:

$.ajax({
       type: "POST",
       url: "/Controller/Action", // the URL of the controller action method
       data: null, // optional data
       success: function(result) {
            // do something with result
       },
     success: function(result, para) {
        if(para == 'something'){
            //run JavaScript function
        }
      },                
       error : function(req, status, error) {
            // do something with error   
       }
   });

from controller you can return two values as following:

return Json(new { json = jr.Data, value2 = "value2" });

How do I change a single value in a data.frame?

In RStudio you can write directly in a cell. Suppose your data.frame is called myDataFrame and the row and column are called columnName and rowName. Then the code would look like:

myDataFrame["rowName", "columnName"] <- value

Hope that helps!

How to sort an array in Bash

try this:

echo ${array[@]} | awk 'BEGIN{RS=" ";} {print $1}' | sort

Output will be:

3
5
a
b
c
f

Problem solved.

Detect the Enter key in a text input field

This code handled every input for me in the whole site. It checks for the ENTER KEY inside an INPUT field and doesn't stop on TEXTAREA or other places.

$(document).on("keydown", "input", function(e){
 if(e.which == 13){
  event.preventDefault();
  return false;
 }
});

CSS full screen div with text in the middle

text-align: center will center it horizontally as for vertically put it in a span and give it a css of margin:auto 0; (you will probably also have to give the span a display: block property)

How do I find out what version of Sybase is running

1)From OS level(UNIX):-

dataserver -v

2)From Syabse isql:-

select @@version
go

sp_version
go

Android Design Support Library expandable Floating Action Button(FAB) menu

  • First create the menu layouts in the your Activity layout xml file. For e.g. a linear layout with horizontal orientation and include a TextView for label then a Floating Action Button beside the TextView.

  • Create the menu layouts as per your need and number.

  • Create a Base Floating Action Button and on its click of that change the visibility of the Menu Layouts.

Please check the below code for the reference and for more info checkout my project from github

Checkout project from Github

<android.support.constraint.ConstraintLayout
            android:id="@+id/activity_main"
            android:layout_width="match_parent"
            android:layout_height="match_parent"
            tools:context="com.app.fabmenu.MainActivity">

            <android.support.design.widget.FloatingActionButton
                android:id="@+id/baseFloatingActionButton"
                android:layout_width="wrap_content"
                android:layout_height="wrap_content"
                android:layout_marginBottom="16dp"
                android:layout_marginEnd="16dp"
                android:layout_marginRight="16dp"
                android:clickable="true"
                android:onClick="@{FabHandler::onBaseFabClick}"
                android:tint="@android:color/white"
                app:fabSize="normal"
                app:layout_constraintBottom_toBottomOf="@+id/activity_main"
                app:layout_constraintRight_toRightOf="@+id/activity_main"
                app:srcCompat="@drawable/ic_add_black_24dp" />

            <LinearLayout
                android:id="@+id/shareLayout"
                android:layout_width="wrap_content"
                android:layout_height="wrap_content"
                android:layout_marginBottom="12dp"
                android:layout_marginEnd="24dp"
                android:layout_marginRight="24dp"
                android:gravity="center_vertical"
                android:orientation="horizontal"
                android:visibility="invisible"
                app:layout_constraintBottom_toTopOf="@+id/createLayout"
                app:layout_constraintLeft_toLeftOf="@+id/createLayout"
                app:layout_constraintRight_toRightOf="@+id/activity_main">

                <TextView
                    android:id="@+id/shareLabelTextView"
                    android:layout_width="wrap_content"
                    android:layout_height="wrap_content"
                    android:layout_marginEnd="8dp"
                    android:layout_marginRight="8dp"
                    android:background="@drawable/shape_fab_label"
                    android:elevation="2dp"
                    android:fontFamily="sans-serif"
                    android:padding="5dip"
                    android:text="Share"
                    android:textColor="@android:color/white"
                    android:typeface="normal" />


                <android.support.design.widget.FloatingActionButton
                    android:id="@+id/shareFab"
                    android:layout_width="wrap_content"
                    android:layout_height="wrap_content"
                    android:clickable="true"
                    android:onClick="@{FabHandler::onShareFabClick}"
                    android:tint="@android:color/white"
                    app:fabSize="mini"
                    app:srcCompat="@drawable/ic_share_black_24dp" />

            </LinearLayout>

            <LinearLayout
                android:id="@+id/createLayout"
                android:layout_width="wrap_content"
                android:layout_height="wrap_content"
                android:layout_marginBottom="24dp"
                android:layout_marginEnd="24dp"
                android:layout_marginRight="24dp"
                android:gravity="center_vertical"
                android:orientation="horizontal"
                android:visibility="invisible"
                app:layout_constraintBottom_toTopOf="@+id/baseFloatingActionButton"
                app:layout_constraintRight_toRightOf="@+id/activity_main">

                <TextView
                    android:id="@+id/createLabelTextView"
                    android:layout_width="wrap_content"
                    android:layout_height="wrap_content"
                    android:layout_marginEnd="8dp"
                    android:layout_marginRight="8dp"
                    android:background="@drawable/shape_fab_label"
                    android:elevation="2dp"
                    android:fontFamily="sans-serif"
                    android:padding="5dip"
                    android:text="Create"
                    android:textColor="@android:color/white"
                    android:typeface="normal" />

                <android.support.design.widget.FloatingActionButton
                    android:id="@+id/createFab"
                    android:layout_width="wrap_content"
                    android:layout_height="wrap_content"
                    android:clickable="true"
                    android:onClick="@{FabHandler::onCreateFabClick}"
                    android:tint="@android:color/white"
                    app:fabSize="mini"
                    app:srcCompat="@drawable/ic_create_black_24dp" />

            </LinearLayout>

        </android.support.constraint.ConstraintLayout>

These are the animations-

Opening animation of FAB Menu:

<?xml version="1.0" encoding="utf-8"?>
<set xmlns:android="http://schemas.android.com/apk/res/android"
android:fillAfter="true">
<scale
    android:duration="300"
    android:fromXScale="0"
    android:fromYScale="0"
    android:interpolator="@android:anim/linear_interpolator"
    android:pivotX="50%"
    android:pivotY="50%"
    android:toXScale="1"
    android:toYScale="1" />
<alpha
    android:duration="300"
    android:fromAlpha="0.0"
    android:interpolator="@android:anim/accelerate_interpolator"
    android:toAlpha="1.0" />

</set>

Closing animation of FAB Menu:

<?xml version="1.0" encoding="utf-8"?>
<set xmlns:android="http://schemas.android.com/apk/res/android"
android:fillAfter="true">
<scale
    android:duration="300"
    android:fromXScale="1"
    android:fromYScale="1"
    android:interpolator="@android:anim/linear_interpolator"
    android:pivotX="50%"
    android:pivotY="50%"
    android:toXScale="0.0"
    android:toYScale="0.0" />
<alpha
    android:duration="300"
    android:fromAlpha="1.0"
    android:interpolator="@android:anim/accelerate_interpolator"
    android:toAlpha="0.0" />
</set>

Then in my Activity I've simply used the animations above to show and hide the FAB menu :

Show Fab Menu:

  private void expandFabMenu() {

    ViewCompat.animate(binding.baseFloatingActionButton).rotation(45.0F).withLayer().setDuration(300).setInterpolator(new OvershootInterpolator(10.0F)).start();
    binding.createLayout.startAnimation(fabOpenAnimation);
    binding.shareLayout.startAnimation(fabOpenAnimation);
    binding.createFab.setClickable(true);
    binding.shareFab.setClickable(true);
    isFabMenuOpen = true;

}

Close Fab Menu:

private void collapseFabMenu() {

    ViewCompat.animate(binding.baseFloatingActionButton).rotation(0.0F).withLayer().setDuration(300).setInterpolator(new OvershootInterpolator(10.0F)).start();
    binding.createLayout.startAnimation(fabCloseAnimation);
    binding.shareLayout.startAnimation(fabCloseAnimation);
    binding.createFab.setClickable(false);
    binding.shareFab.setClickable(false);
    isFabMenuOpen = false;

}

Here is the the Activity class -

package com.app.fabmenu;

import android.databinding.DataBindingUtil;
import android.os.Bundle;
import android.support.design.widget.Snackbar;
import android.support.v4.view.ViewCompat;
import android.support.v7.app.AppCompatActivity;
import android.view.View;
import android.view.animation.Animation;
import android.view.animation.AnimationUtils;
import android.view.animation.OvershootInterpolator;

import com.app.fabmenu.databinding.ActivityMainBinding;

public class MainActivity extends AppCompatActivity {

private ActivityMainBinding binding;
private Animation fabOpenAnimation;
private Animation fabCloseAnimation;
private boolean isFabMenuOpen = false;

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

    binding = DataBindingUtil.setContentView(this,    R.layout.activity_main);
    binding.setFabHandler(new FabHandler());

    getAnimations();


}

private void getAnimations() {

    fabOpenAnimation = AnimationUtils.loadAnimation(this, R.anim.fab_open);

    fabCloseAnimation = AnimationUtils.loadAnimation(this, R.anim.fab_close);

}

private void expandFabMenu() {

    ViewCompat.animate(binding.baseFloatingActionButton).rotation(45.0F).withLayer().setDuration(300).setInterpolator(new OvershootInterpolator(10.0F)).start();
    binding.createLayout.startAnimation(fabOpenAnimation);
    binding.shareLayout.startAnimation(fabOpenAnimation);
    binding.createFab.setClickable(true);
    binding.shareFab.setClickable(true);
    isFabMenuOpen = true;


}

private void collapseFabMenu() {

    ViewCompat.animate(binding.baseFloatingActionButton).rotation(0.0F).withLayer().setDuration(300).setInterpolator(new OvershootInterpolator(10.0F)).start();
    binding.createLayout.startAnimation(fabCloseAnimation);
    binding.shareLayout.startAnimation(fabCloseAnimation);
    binding.createFab.setClickable(false);
    binding.shareFab.setClickable(false);
    isFabMenuOpen = false;

}


public class FabHandler {

    public void onBaseFabClick(View view) {

        if (isFabMenuOpen)
            collapseFabMenu();
        else
            expandFabMenu();


    }

    public void onCreateFabClick(View view) {

        Snackbar.make(binding.coordinatorLayout, "Create FAB tapped", Snackbar.LENGTH_SHORT).show();

    }

    public void onShareFabClick(View view) {

        Snackbar.make(binding.coordinatorLayout, "Share FAB tapped", Snackbar.LENGTH_SHORT).show();

    }


}

@Override
public void onBackPressed() {

    if (isFabMenuOpen)
        collapseFabMenu();
    else
        super.onBackPressed();
}
}

Here are the screenshots

Floating Action Menu with Label Textview in new Cursive Font Family of Android

Floating Action Menu with Label Textview in new Roboto Font Family of Android

Is it possible to register a http+domain-based URL Scheme for iPhone apps, like YouTube and Maps?

BUILDING Again on Nathan and JB's Answer:

How To Launch App From url w/o Extra Click If you prefer a solution that does not include the interim step of clicking a link, the following can be used. With this javascript, I was able to return a Httpresponse object from Django/Python that successfully launches an app if it is installed or alternatively launches the app store in the case of a time out. Note I also needed to adjust the timeout period from 500 to 100 in order for this to work on an iPhone 4S. Test and tweak to get it right for your situation.

<html>
<head>
   <meta name="viewport" content="width=device-width" />
</head>
<body>

<script type="text/javascript">

// To avoid the "protocol not supported" alert, fail must open another app.
var appstorefail = "itms://itunes.apple.com/us/app/facebook/id284882215?mt=8&uo=6";

var loadedAt = +new Date;
setTimeout(
  function(){
    if (+new Date - loadedAt < 2000){
      window.location = appstorefail;
    }
  }
,100);

function LaunchApp(){
  window.open("unknown://nowhere","_self");
};
LaunchApp()
</script>
</body>
</html>

Facebook Architecture

"Knowing about sites which handles such massive traffic gives lots of pointers for architects etc. to keep in mind certain stuff while designing new sites"

I think you can probably learn a lot from the design of Facebook, just as you can from the design of any successful large software system. However, it seems to me that you should not keep the current design of Facebook in mind when designing new systems.

Why do you want to be able to handle the traffic that Facebook has to handle? Odds are that you will never have to, no matter how talented a programmer you may be. Facebook itself was not designed from the start for such massive scalability, which is perhaps the most important lesson to learn from it.

If you want to learn about a non-trivial software system I can recommend the book "Dissecting a C# Application" about the development of the SharpDevelop IDE. It is out of print, but it is available for free online. The book gives you a glimpse into a real application and provides insights about IDEs which are useful for a programmer.

Pandas DataFrame Groupby two columns and get counts

Should you want to add a new column (say 'count_column') containing the groups' counts into the dataframe:

df.count_column=df.groupby(['col5','col2']).col5.transform('count')

(I picked 'col5' as it contains no nan)

Compiling a java program into an executable

There is a small handful of programs that do that... TowerJ is one that comes to mind (I'll let you Google for it) but it costs significant money.

The most useful reference for this topic I found is at: http://mindprod.com/jgloss/nativecompiler.html

it mentions a few other products, and alternatives to achieve the same purpose.

When to use SELECT ... FOR UPDATE?

The only portable way to achieve consistency between rooms and tags and making sure rooms are never returned after they had been deleted is locking them with SELECT FOR UPDATE.

However in some systems locking is a side effect of concurrency control, and you achieve the same results without specifying FOR UPDATE explicitly.


To solve this problem, Thread 1 should SELECT id FROM rooms FOR UPDATE, thereby preventing Thread 2 from deleting from rooms until Thread 1 is done. Is that correct?

This depends on the concurrency control your database system is using.

  • MyISAM in MySQL (and several other old systems) does lock the whole table for the duration of a query.

  • In SQL Server, SELECT queries place shared locks on the records / pages / tables they have examined, while DML queries place update locks (which later get promoted to exclusive or demoted to shared locks). Exclusive locks are incompatible with shared locks, so either SELECT or DELETE query will lock until another session commits.

  • In databases which use MVCC (like Oracle, PostgreSQL, MySQL with InnoDB), a DML query creates a copy of the record (in one or another way) and generally readers do not block writers and vice versa. For these databases, a SELECT FOR UPDATE would come handy: it would lock either SELECT or the DELETE query until another session commits, just as SQL Server does.

When should one use REPEATABLE_READ transaction isolation versus READ_COMMITTED with SELECT ... FOR UPDATE?

Generally, REPEATABLE READ does not forbid phantom rows (rows that appeared or disappeared in another transaction, rather than being modified)

  • In Oracle and earlier PostgreSQL versions, REPEATABLE READ is actually a synonym for SERIALIZABLE. Basically, this means that the transaction does not see changes made after it has started. So in this setup, the last Thread 1 query will return the room as if it has never been deleted (which may or may not be what you wanted). If you don't want to show the rooms after they have been deleted, you should lock the rows with SELECT FOR UPDATE

  • In InnoDB, REPEATABLE READ and SERIALIZABLE are different things: readers in SERIALIZABLE mode set next-key locks on the records they evaluate, effectively preventing the concurrent DML on them. So you don't need a SELECT FOR UPDATE in serializable mode, but do need them in REPEATABLE READ or READ COMMITED.

Note that the standard on isolation modes does prescribe that you don't see certain quirks in your queries but does not define how (with locking or with MVCC or otherwise).

When I say "you don't need SELECT FOR UPDATE" I really should have added "because of side effects of certain database engine implementation".

Include an SVG (hosted on GitHub) in MarkDown

Update 2020: how they made it work while avoiding XSS attacks

GitHub appears to use two security approaches, this is a good article: https://digi.ninja/blog/svg_xss.php see also: https://security.stackexchange.com/questions/148507/how-to-prevent-xss-in-svg-file-upload

Update 2017

A GitHub dev is currently looking into this: https://github.com/github/markup/issues/556#issuecomment-306103203

Update 2014-12: GitHub now renders SVG on blob show, so I don't see any reason why not to render on README renderings:

Also note that that SVG does have an XSS attempt but it does not run: https://raw.githubusercontent.com/cirosantilli/test/2144a93333be144152e8b0d4144b77b211afce63/svg.svg

The billion laugh SVG does make Firefox 44 Freeze, but Chromium 48 is OK: https://github.com/cirosantilli/web-cheat/blob/master/svg-billion-laughs.svg

Petah mentioned that blobs are fine because the SVG is inside an iframe.

Possible rationale for GitHub not serving SVG images

The following questions asks about the risks of SVG in general: https://security.stackexchange.com/questions/11384/exploits-or-other-security-risks-with-svg-upload

Using IQueryable with Linq

It allows for further querying further down the line. If this was beyond a service boundary say, then the user of this IQueryable object would be allowed to do more with it.

For instance if you were using lazy loading with nhibernate this might result in graph being loaded when/if needed.

How do I call a specific Java method on a click/submit event of a specific button in JSP?

Just give the individual button elements a unique name. When pressed, the button's name is available as a request parameter the usual way like as with input elements.

You only need to make sure that the button inputs have type="submit" as in <input type="submit"> and <button type="submit"> and not type="button", which only renders a "dead" button purely for onclick stuff and all.

E.g.

<form action="${pageContext.request.contextPath}/myservlet" method="post">
    <input type="submit" name="button1" value="Button 1" />
    <input type="submit" name="button2" value="Button 2" />
    <input type="submit" name="button3" value="Button 3" />
</form>

with

@WebServlet("/myservlet")
public class MyServlet extends HttpServlet {

    @Override
    protected void doPost(HttpServletRequest request, HttpServletResponse response) throws ServletException, IOException {
        MyClass myClass = new MyClass();

        if (request.getParameter("button1") != null) {
            myClass.method1();
        } else if (request.getParameter("button2") != null) {
            myClass.method2();
        } else if (request.getParameter("button3") != null) {
            myClass.method3();
        } else {
            // ???
        }

        request.getRequestDispatcher("/WEB-INF/some-result.jsp").forward(request, response);
    }

}

Alternatively, use <button type="submit"> instead of <input type="submit">, then you can give them all the same name, but an unique value. The value of the <button> won't be used as label, you can just specify that yourself as child.

E.g.

<form action="${pageContext.request.contextPath}/myservlet" method="post">
    <button type="submit" name="button" value="button1">Button 1</button>
    <button type="submit" name="button" value="button2">Button 2</button>
    <button type="submit" name="button" value="button3">Button 3</button>
</form>

with

@WebServlet("/myservlet")
public class MyServlet extends HttpServlet {

    @Override
    protected void doPost(HttpServletRequest request, HttpServletResponse response) throws ServletException, IOException {
        MyClass myClass = new MyClass();
        String button = request.getParameter("button");

        if ("button1".equals(button)) {
            myClass.method1();
        } else if ("button2".equals(button)) {
            myClass.method2();
        } else if ("button3".equals(button)) {
            myClass.method3();
        } else {
            // ???
        }

        request.getRequestDispatcher("/WEB-INF/some-result.jsp").forward(request, response);
    }

}

See also:

Kill python interpeter in linux from the terminal

You can try the killall command:

killall python

How to establish ssh key pair when "Host key verification failed"

When you try to connect your remote server with ssh:

$ ssh username@ip_address

then the error raise, to solve it:

$ ssh-keygen -f "/home/local_username/.ssh/known_hosts" -R "ip_address"

What's the Android ADB shell "dumpsys" tool and what are its benefits?

According to official Android information about dumpsys:

The dumpsys tool runs on the device and provides information about the status of system services.

To get a list of available services use

adb shell dumpsys -l

Twitter bootstrap modal-backdrop doesn't disappear

I just spent way too long on this problem :)

While the other answers provided are helpful and valid, it seemed a little messy to me to effectively recreate the modal hiding functionality from Bootstrap, so I found a cleaner solution.

The problem is that there are a chain of events that happen when you call

$("#myModal").modal('hide');
functionThatEndsUpDestroyingTheDOM()

When you then replace a bunch of HTML as the result of the AJAX request, the modal-hiding events don't finish. However, Bootstrap triggers an event when everything is finished, and you can hook into that like so:

$("#myModal").modal('hide').on('hidden.bs.modal', functionThatEndsUpDestroyingTheDOM);

Hope this is helpful!

Python - Locating the position of a regex match in a string?

You could use .find("is"), it would return position of "is" in the string

or use .start() from re

>>> re.search("is", String).start()
2

Actually its match "is" from "This"

If you need to match per word, you should use \b before and after "is", \b is the word boundary.

>>> re.search(r"\bis\b", String).start()
5
>>>

for more info about python regular expressions, docs here

batch file to list folders within a folder to one level

print all folders name where batch script file is kept

for /d %%d in (*.*) do (
    set test=%%d
    echo !test!
)
pause

How to replace a character from a String in SQL?

Are you sure that the data stored in the database is actually a question mark? I would tend to suspect from the sample data that the problem is one of character set conversion where ? is being used as the replacement character when the character can't be represented in the client character set. Possibly, the database is actually storing Microsoft "smart quote" characters rather than simple apostrophes.

What does the DUMP function show is actually stored in the database?

SELECT column_name,
       dump(column_name,1016)
  FROM your_table
 WHERE <<predicate that returns just the sample data you posted>>

What application are you using to view the data? What is the client's NLS_LANG set to?

What is the database and national character set? Is the data stored in a VARCHAR2 column? Or NVARCHAR2?

SELECT parameter, value
  FROM v$nls_parameters
 WHERE parameter LIKE '%CHARACTERSET';

If all the problem characters are stored in the database as 0x19 (decimal 25), your REPLACE would need to be something like

UPDATE table_name
   SET column1 = REPLACE(column1, chr(25), q'[']'),
       column2 = REPLACE(column2, chr(25), q'[']'),
       ...
       columnN = REPLACE(columnN, chr(25), q'[']')
 WHERE INSTR(column1,chr(25)) > 0
    OR INSTR(column2,chr(25)) > 0 
    ...
    OR INSTR(columnN,chr(25)) > 0

How do I test which class an object is in Objective-C?

To test if object is an instance of class a:

[yourObject isKindOfClass:[a class]]
// Returns a Boolean value that indicates whether the receiver is an instance of 
// given class or an instance of any class that inherits from that class.

or

[yourObject isMemberOfClass:[a class]]
// Returns a Boolean value that indicates whether the receiver is an instance of a 
// given class.

To get object's class name you can use NSStringFromClass function:

NSString *className = NSStringFromClass([yourObject class]);

or c-function from objective-c runtime api:

#import <objc/runtime.h>

/* ... */

const char* className = class_getName([yourObject class]);
NSLog(@"yourObject is a: %s", className);

EDIT: In Swift

if touch.view is UIPickerView {
    // touch.view is of type UIPickerView
}

Is it possible to access to google translate api for free?

Yes, you can use GT for free. See the post with explanation. And look at repo on GitHub.

UPD 19.03.2019 Here is a version for browser on GitHub.

How do I get a python program to do nothing?

The pass command is what you are looking for. Use pass for any construct that you want to "ignore". Your example uses a conditional expression but you can do the same for almost anything.

For your specific use case, perhaps you'd want to test the opposite condition and only perform an action if the condition is false:

if num2 != num5:
    make_some_changes()

This will be the same as this:

if num2 == num5:
    pass
else:
    make_some_changes()

That way you won't even have to use pass and you'll also be closer to adhering to the "Flatter is better than nested" convention in PEP20.


You can read more about the pass statement in the documentation:

The pass statement does nothing. It can be used when a statement is required syntactically but the program requires no action.

if condition:
    pass
try:
    make_some_changes()
except Exception:
    pass # do nothing
class Foo():
    pass # an empty class definition
def bar():
    pass # an empty function definition

How can I check if a background image is loaded?

https://github.com/alexanderdickson/waitForImages

$('selector').waitForImages({
    finished: function() {
       // ...
    },
    each: function() {
       // ...
    },
    waitForAll: true
});

How do I clone into a non-empty directory?

This worked for me:

git init
git remote add origin PATH/TO/REPO
git fetch
git reset origin/master  # Required when the versioned files existed in path before "git init" of this repo.
git checkout -t origin/master

NOTE: -t will set the upstream branch for you, if that is what you want, and it usually is.

Why is super.super.method(); not allowed in Java?

I would put the super.super method body in another method, if possible

class SuperSuperClass {
    public String toString() {
        return DescribeMe();
    }

    protected String DescribeMe() {
        return "I am super super";
    }
}

class SuperClass extends SuperSuperClass {
    public String toString() {
        return "I am super";
    }
}

class ChildClass extends SuperClass {
    public String toString() {
        return DescribeMe();
    }
}

Or if you cannot change the super-super class, you can try this:

class SuperSuperClass {
    public String toString() {
        return "I am super super";
    }
}

class SuperClass extends SuperSuperClass {
    public String toString() {
        return DescribeMe(super.toString());
    }

    protected String DescribeMe(string fromSuper) {
        return "I am super";
    }
}

class ChildClass extends SuperClass {
    protected String DescribeMe(string fromSuper) {
        return fromSuper;
    }
}

In both cases, the

new ChildClass().toString();

results to "I am super super"

Python constructor and default value

Mutable default arguments don't generally do what you want. Instead, try this:

class Node:
     def __init__(self, wordList=None, adjacencyList=None):
        if wordList is None:
            self.wordList = []
        else:
             self.wordList = wordList 
        if adjacencyList is None:
            self.adjacencyList = []
        else:
             self.adjacencyList = adjacencyList 

Rails - How to use a Helper Inside a Controller

One alternative missing from other answers is that you can go the other way around: define your method in your Controller, and then use helper_method to make it also available on views as, you know, a helper method.

For instance:


class ApplicationController < ActionController::Base

private

  def something_count
    # All other controllers that inherit from ApplicationController will be able to call `something_count`
  end
  # All views will be able to call `something_count` as well
  helper_method :something_count 

end

Wait for async task to finish

How about calling a function from within your callback instead of returning a value in sync_call()?

function sync_call(input) {
    var value;

    // Assume the async call always succeed
    async_call(input, function(result) {
        value = result;
        use_value(value);
    } );
}

Get the current time in C

Easy way:

#include <time.h>
#include <stdio.h>
#include <string.h>

int main(void)
{
    time_t mytime = time(NULL);
    char * time_str = ctime(&mytime);
    time_str[strlen(time_str)-1] = '\0';
    printf("Current Time : %s\n", time_str);

    return 0;
}

How can I change the text inside my <span> with jQuery?

This will be used to change the Html content inside the span

 $('#abc span').html('goes inside the span');

if you want to change the text inside the span, you can use:

 $('#abc span').text('goes inside the span');

How to convert datetime to timestamp using C#/.NET (ignoring current timezone)

I'm not exactly sure what it is that you want. Do you want a TimeStamp? Then you can do something simple like:

TimeStamp ts = TimeStamp.FromTicks(value.ToUniversalTime().Ticks);

Since you named a variable epoch, do you want the Unix time equivalent of your date?

DateTime unixStart = DateTime.SpecifyKind(new DateTime(1970, 1, 1), DateTimeKind.Utc);
long epoch = (long)Math.Floor((value.ToUniversalTime() - unixStart).TotalSeconds);

Web Application Problems (web.config errors) HTTP 500.19 with IIS7.5 and ASP.NET v2

I had the same issue in Windows 7.

The solution was to go to basic settings > connect as > specific user - and log in as a user, instead of the default 'pass-through'

This fixed the issue for me.

How to preserve aspect ratio when scaling image using one (CSS) dimension in IE6?

The only way to do explicit scaling in CSS is to use tricks such as found here.

IE6 only, you could also use filters (check out PNGFix). But applying them automatically to the page will need javascript, though that javascript could be embedded in the CSS file.

If you are going to require javascript, then you might want to just have javascript fill in the missing value for the height by inspecting the image once the content has loaded. (Sorry I do not have a reference for this technique).

Finally, and pardon me for this soapbox, you might want to eschew IE6 support in this matter. You could add _width: auto after your width: 75px rule, so that IE6 at least renders the image reasonably, even if it is the wrong size.

I recommend the last solution simply because IE6 is on the way out: 20% and going down almost a percent a month. Also, I note that your site is recreational and in the UK. Both of these help the demographic lean to be away from IE6: IE6 usage drops nearly 40% during weekends (no citation sorry), and UK has a much lower IE6 demographic (again no citation, sorry).

Good luck!

Working with INTERVAL and CURDATE in MySQL

As suggested by A Star, I always use something along the lines of:

DATE(NOW()) - INTERVAL 1 MONTH

Similarly you can do:

NOW() + INTERVAL 5 MINUTE
"2013-01-01 00:00:00" + INTERVAL 10 DAY

and so on. Much easier than typing DATE_ADD or DATE_SUB all the time :)!

Create a .csv file with values from a Python list

Use python's csv module for reading and writing comma or tab-delimited files. The csv module is preferred because it gives you good control over quoting.

For example, here is the worked example for you:

import csv
data = ["value %d" % i for i in range(1,4)]

out = csv.writer(open("myfile.csv","w"), delimiter=',',quoting=csv.QUOTE_ALL)
out.writerow(data)

Produces:

"value 1","value 2","value 3"

What is the difference between print and puts?

If you would like to output array within string using puts, you will get the same result as if you were using print:

puts "#{[0, 1, nil]}":
[0, 1, nil]

But if not withing a quoted string then yes. The only difference is between new line when we use puts.

Remove a CLASS for all child elements

This should work:

$("#table-filters>ul>li.active").removeClass("active");
//Find all `li`s with class `active`, children of `ul`s, children of `table-filters`

HTML text input allow only numeric input

JavaScript code:

function validate(evt)
{
    if(evt.keyCode!=8)
    {
        var theEvent = evt || window.event;
        var key = theEvent.keyCode || theEvent.which;
        key = String.fromCharCode(key);
        var regex = /[0-9]|\./;
        if (!regex.test(key))
        {
            theEvent.returnValue = false;

            if (theEvent.preventDefault)
                theEvent.preventDefault();
            }
        }
    }

HTML code:

<input type='text' name='price' value='0' onkeypress='validate(event)'/>

works perfectly because the backspace keycode is 8 and a regex expression doesn't let it, so it's an easy way to bypass the bug :)

How to enable CORS in flask

Improving the solution described here: https://stackoverflow.com/a/52875875/10299604

With after_request we can handle the CORS response headers avoiding to add extra code to our endpoints:

    ### CORS section
    @app.after_request
    def after_request_func(response):
        origin = request.headers.get('Origin')
        if request.method == 'OPTIONS':
            response = make_response()
            response.headers.add('Access-Control-Allow-Credentials', 'true')
            response.headers.add('Access-Control-Allow-Headers', 'Content-Type')
            response.headers.add('Access-Control-Allow-Headers', 'x-csrf-token')
            response.headers.add('Access-Control-Allow-Methods',
                                'GET, POST, OPTIONS, PUT, PATCH, DELETE')
            if origin:
                response.headers.add('Access-Control-Allow-Origin', origin)
        else:
            response.headers.add('Access-Control-Allow-Credentials', 'true')
            if origin:
                response.headers.add('Access-Control-Allow-Origin', origin)

        return response
    ### end CORS section

Can you use Microsoft Entity Framework with Oracle?

DevArt's OraDirect provider now supports entity framework. See http://devart.com/news/2008/directs475.html

Split string based on a regular expression

When you use re.split and the split pattern contains capturing groups, the groups are retained in the output. If you don't want this, use a non-capturing group instead.

CSV in Python adding an extra carriage return, on Windows

While @john-machin gives a good answer, it's not always the best approach. For example, it doesn't work on Python 3 unless you encode all of your inputs to the CSV writer. Also, it doesn't address the issue if the script wants to use sys.stdout as the stream.

I suggest instead setting the 'lineterminator' attribute when creating the writer:

import csv
import sys

doc = csv.writer(sys.stdout, lineterminator='\n')
doc.writerow('abc')
doc.writerow(range(3))

That example will work on Python 2 and Python 3 and won't produce the unwanted newline characters. Note, however, that it may produce undesirable newlines (omitting the LF character on Unix operating systems).

In most cases, however, I believe that behavior is preferable and more natural than treating all CSV as a binary format. I provide this answer as an alternative for your consideration.

Returning JSON from PHP to JavaScript?

There's a JSON section in the PHP's documentation. You'll need PHP 5.2.0 though.

As of PHP 5.2.0, the JSON extension is bundled and compiled into PHP by default.

If you don't, here's the PECL library you can install.

<?php
    $arr = array ('a'=>1,'b'=>2,'c'=>3,'d'=>4,'e'=>5);

    echo json_encode($arr); // {"a":1,"b":2,"c":3,"d":4,"e":5}
?>

swift UITableView set rowHeight

Problem Cause:
The problem is that the cell has not been created yet. TableView first calculates the height for row and then populates the data for each row, so the rows array has not been created when heightForRow method gets called. So your app is trying to access a memory location which it does not have the permission to and therefor you get the EXC_BAD_ACCESS message.

How to achieve self sizing TableViewCell in UITableView:
Just set proper constraints for your views contained in TableViewCell's view in StoryBoard. Remember you shouldn't set height constraints to TableViewCell's root view, its height should be properly computable by the height of its subviews -- This is like what you do to set proper constraints for UIScrollView. This way your cells will get different heights according to their subviews. No additional action needed

How to call a method with a separate thread in Java?

Sometime ago, I had written a simple utility class that uses JDK5 executor service and executes specific processes in the background. Since doWork() typically would have a void return value, you may want to use this utility class to execute it in the background.

See this article where I had documented this utility.

unknown error: Chrome failed to start: exited abnormally (Driver info: chromedriver=2.9

  1. Check that you use ChromeDriver version that corresponds to your Chrome version
  2. In case you are on Linux without graphical interface "headless" mode must be used

Example of WebDriverSettings.java :

...
ChromeOptions options = new ChromeOptions();
options.setExperimentalOption("prefs", chromePrefs);
options.addArguments("--no-sandbox");
options.addArguments("--headless"); //!!!should be enabled for Jenkins
options.addArguments("--disable-dev-shm-usage"); //!!!should be enabled for Jenkins
options.addArguments("--window-size=1920x1080"); //!!!should be enabled for Jenkins
driver = new ChromeDriver(options);
...

How to install Laravel's Artisan?

Use the project's root folder

Artisan comes with Laravel by default, if your php command works fine, then the only thing you need to do is to navigate to the project's root folder. The root folder is the parent folder of the app folder. For example:

cd c:\Program Files\xampp\htdocs\your-project-name

Now the php artisan list command should work fine, because PHP runs the file called artisan in the project's folder.

Install the framework

Keep in mind that Artisan runs scripts stored in the vendor folder, so if you installed Laravel without Composer, like downloading and extracting the Laravel GitHub repo, then you don't have the framework itself and you may get the following error when you try to use Artisan:

Could not open input file: artisan

To solve this you have to install the framework itself by running composer install in your project's root folder.

The easiest way to replace white spaces with (underscores) _ in bash

You can do it using only the shell, no need for tr or sed

$ str="This is just a test"
$ echo ${str// /_}
This_is_just_a_test

How to find the size of integer array

If array is static allocated:

size_t size = sizeof(arr) / sizeof(int);

if array is dynamic allocated(heap):

int *arr = malloc(sizeof(int) * size);

where variable size is a dimension of the arr.

VirtualBox: mount.vboxsf: mounting failed with the error: No such device

If you're on Debian:

1) remove all installed package through Virtualbox Guest Additions ISO file:

sh /media/cdrom/VBoxLinuxAdditions.run uninstall

2) install Virtualbox packages:

apt-get install build-essential module-assistant virtualbox-guest-dkms virtualbox-guest-utils

Note that even with modprobe vboxsf returning nothing (so the module is correctly loaded), the vboxsf.so will call an executable named mount.vboxsf, which is provided by virtualbox-guest-utils. Ignoring this one will prevent you from understanding the real cause of the error.

strace mount /your-directory was a great help (No such file or directory on /sbin/mount.vboxsf).

Converting Long to Date in Java returns 1970

1220227200 corresponds to Jan 15 1980 (and indeed new Date(1220227200).toString() returns "Thu Jan 15 03:57:07 CET 1970"). If you pass a long value to a date, that is before 01/01/1970 it will in fact return a date of 01/01/1970. Make sure that your values are not in this situation (lower than 82800000).

INSTALL_FAILED_USER_RESTRICTED : android studio using redmi 4 device

Xiaomi MIUI.

Options - Permissions - Install via USB (not the same item in Developers options!) then uncheck your disabled app

Get an element by index in jQuery

$(...)[index]      // gives you the DOM element at index
$(...).get(index)  // gives you the DOM element at index
$(...).eq(index)   // gives you the jQuery object of element at index

DOM objects don't have css function, use the last...

$('ul li').eq(index).css({'background-color':'#343434'});

docs:

.get(index) Returns: Element

.eq(index) Returns: jQuery

R memory management / cannot allocate vector of size n Mb

Here is a presentation on this topic that you might find interesting:

http://www.bytemining.com/2010/08/taking-r-to-the-limit-part-ii-large-datasets-in-r/

I haven't tried the discussed things myself, but the bigmemory package seems very useful

Generic type conversion FROM string

lubos hasko's method fails for nullables. The method below will work for nullables. I didn't come up with it, though. I found it via Google: http://web.archive.org/web/20101214042641/http://dogaoztuzun.com/post/C-Generic-Type-Conversion.aspx Credit to "Tuna Toksoz"

Usage first:

TConverter.ChangeType<T>(StringValue);  

The class is below.

public static class TConverter
{
    public static T ChangeType<T>(object value)
    {
        return (T)ChangeType(typeof(T), value);
    }

    public static object ChangeType(Type t, object value)
    {
        TypeConverter tc = TypeDescriptor.GetConverter(t);
        return tc.ConvertFrom(value);
    }

    public static void RegisterTypeConverter<T, TC>() where TC : TypeConverter
    {

        TypeDescriptor.AddAttributes(typeof(T), new TypeConverterAttribute(typeof(TC)));
    }
}

jQuery UI 1.10: dialog and zIndex option

You don't tell it, but you are using jQuery UI 1.10.

In jQuery UI 1.10 the zIndex option is removed:

Removed zIndex option

Similar to the stack option, the zIndex option is unnecessary with a proper stacking implementation. The z-index is defined in CSS and stacking is now controlled by ensuring the focused dialog is the last "stacking" element in its parent.

you have to use pure css to set the dialog "on the top":

.ui-dialog { z-index: 1000 !important ;}

you need the key !important to override the default styling of the element; this affects all your dialogs if you need to set it only for a dialog use the dialogClass option and style it.

If you need a modal dialog set the modal: true option see the docs:

If set to true, the dialog will have modal behavior; other items on the page will be disabled, i.e., cannot be interacted with. Modal dialogs create an overlay below the dialog but above other page elements.

You need to set the modal overlay with an higher z-index to do so use:

.ui-front { z-index: 1000 !important; }

for this element too.

How can I enable Assembly binding logging?

Instead of Creating New Application Pool,You can go to your Existing application Pool->Right click Advance setting->Enable 32-bit Application-----Set to TRUE

How to solve "sign_and_send_pubkey: signing failed: agent refused operation"?

For me the problem was a wrong copy/paste of the public key into Gitlab. The copy generated an extra return. Make sure what you paste is a one-line key.

Changing the child element's CSS when the parent is hovered

Stephen's answer is correct but here's my adaptation of his answer:

HTML

<div class="parent">
    <p> parent 1 </p>
    <div class="child">
        Text Block 1
    </div>
</div>

<div class="parent">
    <p> parent 2 </p>
    <div class="child">
        Text Block 2
    </div>
</div>

CSS

.parent { width: 100px; min-height: 100px; color: red; }
.child { width: 50px; min-height: 20px; color: blue; display: none; }
.parent:hover .child, .parent.hover .child { display: block; }

jQuery

//this is only necessary for IE and should be in a conditional comment

jQuery('.parent').hover(function () {
    jQuery(this).addClass('hover');
}, function () {
    jQuery(this).removeClass('hover');
});

You can see this example working over at jsFiddle.

Xampp MySQL not starting - "Attempting to start MySQL service..."

Did you use the default installation path?

In my case, when i ran mysql_start.bat I got the following error:

Can`t find messagefile 'D:\xampp\mysql\share\errmsg.sys'

I moved my xampp folder to the root of the drive and it started working.

Hope it helps

Ruby Hash to array of values

It is as simple as

hash.values
#=> [["a", "b", "c"], ["b", "c"]]

this will return a new array populated with the values from hash

if you want to store that new array do

array_of_values = hash.values
#=> [["a", "b", "c"], ["b", "c"]]

array_of_values
 #=> [["a", "b", "c"], ["b", "c"]]

String replacement in Objective-C

NSString objects are immutable (they can't be changed), but there is a mutable subclass, NSMutableString, that gives you several methods for replacing characters within a string. It's probably your best bet.

Handle JSON Decode Error when nothing returned

There is a rule in Python programming called "it is Easier to Ask for Forgiveness than for Permission" (in short: EAFP). It means that you should catch exceptions instead of checking values for validity.

Thus, try the following:

try:
    qByUser = byUsrUrlObj.read()
    qUserData = json.loads(qByUser).decode('utf-8')
    questionSubjs = qUserData["all"]["questions"]
except ValueError:  # includes simplejson.decoder.JSONDecodeError
    print 'Decoding JSON has failed'

EDIT: Since simplejson.decoder.JSONDecodeError actually inherits from ValueError (proof here), I simplified the catch statement by just using ValueError.

extract digits in a simple way from a python string

This regular expression handles floats as well

import re
re_float = re.compile(r'\d*\.?\d+')

You could also add a group to the expression that catches your weight units.

re_banana = re.compile(r'(?P<number>\d*\.?\d+)\s?(?P<uni>[a-zA-Z]+)')

You can access the named groups like this re_banana.match("200 kgm").group('number').

I think this should help you getting started.

How to generate a random string of 20 characters

I'd use this approach:

String randomString(final int length) {
    Random r = new Random(); // perhaps make it a class variable so you don't make a new one every time
    StringBuilder sb = new StringBuilder();
    for(int i = 0; i < length; i++) {
        char c = (char)(r.nextInt((int)(Character.MAX_VALUE)));
        sb.append(c);
    }
    return sb.toString();
}

If you want a byte[] you can do this:

byte[] randomByteString(final int length) {
    Random r = new Random();
    byte[] result = new byte[length];
    for(int i = 0; i < length; i++) {
        result[i] = r.nextByte();
    }
    return result;
}

Or you could do this

byte[] randomByteString(final int length) {
    Random r = new Random();
    StringBuilder sb = new StringBuilder();
    for(int i = 0; i < length; i++) {
        char c = (char)(r.nextInt((int)(Character.MAX_VALUE)));
        sb.append(c);
    }
    return sb.toString().getBytes();
}

Could not load file or assembly 'System.Web.Mvc'

We want to add it because we are making a class library that uses it.

For me it is here...

C:\Program Files (x86)\Microsoft ASP.NET\ASP.NET MVC 4\Assemblies

Split output of command by columns using Bash?

try

ps |&
while read -p first second third fourth etc ; do
   if [[ $first == '11383' ]]
   then
       echo got: $fourth
   fi       
done

This Handler class should be static or leaks might occur: IncomingHandler

With the help of @Sogger's answer, I created a generic Handler:

public class MainThreadHandler<T extends MessageHandler> extends Handler {

    private final WeakReference<T> mInstance;

    public MainThreadHandler(T clazz) {
        // Remove the following line to use the current thread.
        super(Looper.getMainLooper());
        mInstance = new WeakReference<>(clazz);
    }

    @Override
    public void handleMessage(Message msg) {
        T clazz = mInstance.get();
        if (clazz != null) {
            clazz.handleMessage(msg);
        }
    }
}

The interface:

public interface MessageHandler {

    void handleMessage(Message msg);

}

I'm using it as follows. But I'm not 100% sure if this is leak-safe. Maybe someone could comment on this:

public class MyClass implements MessageHandler {

    private static final int DO_IT_MSG = 123;

    private MainThreadHandler<MyClass> mHandler = new MainThreadHandler<>(this);

    private void start() {
        // Do it in 5 seconds.
        mHandler.sendEmptyMessageDelayed(DO_IT_MSG, 5 * 1000);
    }

    @Override
    public void handleMessage(Message msg) {
        switch (msg.what) {
            case DO_IT_MSG:
                doIt();
                break;
        }
    }

    ...

}

Converting char[] to byte[]

char[] ch = ?
new String(ch).getBytes();

or

new String(ch).getBytes("UTF-8");

to get non-default charset.

Update: Since Java 7: new String(ch).getBytes(StandardCharsets.UTF_8);

Removing index column in pandas when reading a csv

When reading to and from your CSV file include the argument index=False so for example:

 df.to_csv(filename, index=False)

and to read from the csv

df.read_csv(filename, index=False)  

This should prevent the issue so you don't need to fix it later.

How to access random item in list?

Why not[2]:

public static T GetRandom<T>(this List<T> list)
{
     return list[(int)(DateTime.Now.Ticks%list.Count)];
}

Print a div content using Jquery

Print only selected element on codepen

HTML:

<div class="print">
 <p>Print 1</p>
 <a href="#" class="js-print-link">Click Me To Print</a>
</div>

<div class="print">
 <p>Print 2</p>
 <a href="#" class="js-print-link">Click Me To Print</a>
</div>

JQuery:

$('.js-print-link').on('click', function() {
  var printBlock = $(this).parents('.print').siblings('.print');
  printBlock.hide();
  window.print();
  printBlock.show();
});

Finding Key associated with max Value in a Java Map

1. Using Stream

public <K, V extends Comparable<V>> V maxUsingStreamAndLambda(Map<K, V> map) {
    Optional<Entry<K, V>> maxEntry = map.entrySet()
        .stream()
        .max((Entry<K, V> e1, Entry<K, V> e2) -> e1.getValue()
            .compareTo(e2.getValue())
        );

    return maxEntry.get().getKey();
}

2. Using Collections.max() with a Lambda Expression

    public <K, V extends Comparable<V>> V maxUsingCollectionsMaxAndLambda(Map<K, V> map) {
        Entry<K, V> maxEntry = Collections.max(map.entrySet(), (Entry<K, V> e1, Entry<K, V> e2) -> e1.getValue()
            .compareTo(e2.getValue()));
        return maxEntry.getKey();
    }

3. Using Stream with Method Reference

    public <K, V extends Comparable<V>> V maxUsingStreamAndMethodReference(Map<K, V> map) {
        Optional<Entry<K, V>> maxEntry = map.entrySet()
            .stream()
            .max(Comparator.comparing(Map.Entry::getValue));
        return maxEntry.get()
            .getKey();
    }

4. Using Collections.max()

    public <K, V extends Comparable<V>> V maxUsingCollectionsMax(Map<K, V> map) {
        Entry<K, V> maxEntry = Collections.max(map.entrySet(), new Comparator<Entry<K, V>>() {
            public int compare(Entry<K, V> e1, Entry<K, V> e2) {
                return e1.getValue()
                    .compareTo(e2.getValue());
            }
        });
        return maxEntry.getKey();
    }

5. Using Simple Iteration

public <K, V extends Comparable<V>> V maxUsingIteration(Map<K, V> map) {
    Map.Entry<K, V> maxEntry = null;
    for (Map.Entry<K, V> entry : map.entrySet()) {
        if (maxEntry == null || entry.getValue()
            .compareTo(maxEntry.getValue()) > 0) {
            maxEntry = entry;
        }
    }
    return maxEntry.getKey();
}

Find duplicate entries in a column

Using:

  SELECT t.ctn_no
    FROM YOUR_TABLE t
GROUP BY t.ctn_no
  HAVING COUNT(t.ctn_no) > 1

...will show you the ctn_no value(s) that have duplicates in your table. Adding criteria to the WHERE will allow you to further tune what duplicates there are:

  SELECT t.ctn_no
    FROM YOUR_TABLE t
   WHERE t.s_ind = 'Y'
GROUP BY t.ctn_no
  HAVING COUNT(t.ctn_no) > 1

If you want to see the other column values associated with the duplicate, you'll want to use a self join:

SELECT x.*
  FROM YOUR_TABLE x
  JOIN (SELECT t.ctn_no
          FROM YOUR_TABLE t
      GROUP BY t.ctn_no
        HAVING COUNT(t.ctn_no) > 1) y ON y.ctn_no = x.ctn_no

Add column with constant value to pandas dataframe

With modern pandas you can just do:

df['new'] = 0

How to iterate over a JSONObject?

Maybe this will help:

JSONObject jsonObject = new JSONObject(contents.trim());
Iterator<String> keys = jsonObject.keys();

while(keys.hasNext()) {
    String key = keys.next();
    if (jsonObject.get(key) instanceof JSONObject) {
          // do something with jsonObject here      
    }
}

How do I copy a folder from remote to local using scp?

To use full power of scp you need to go through next steps:

  1. Public key authorisation
  2. Create ssh aliases

Then, for example if you have this ~/.ssh/config:

Host test
    User testuser
    HostName test-site.com
    Port 22022

Host prod
    User produser
    HostName production-site.com
    Port 22022

you'll save yourself from password entry and simplify scp syntax like this:

scp -r prod:/path/foo /home/user/Desktop   # copy to local
scp -r prod:/path/foo test:/tmp            # copy from remote prod to remote test

More over, you will be able to use remote path-completion:

scp test:/var/log/  # press tab twice
Display all 151 possibilities? (y or n)

Update:

For enabling remote bash-completion you need to have bash-shell on both <source> and <target> hosts, and properly working bash-completion. For more information see related questions:

How to enable autocompletion for remote paths when using scp?
SCP filename tab completion

The static keyword and its various uses in C++

In order to clarify the question, I would rather categorize the usage of 'static' keyword in three different forms:

(A). variables

(B). functions

(C). member variables/functions of classes

the explanation follows below for each of the sub headings:

(A) 'static' keyword for variables

This one can be little tricky however if explained and understood properly, it's pretty straightforward.

To explain this, first it is really useful to know about the scope, duration and linkage of variables, without which things are always difficult to see through the murky concept of staic keyword

1. Scope : Determines where in the file, the variable is accessible. It can be of two types: (i) Local or Block Scope. (ii) Global Scope

2. Duration : Determines when a variable is created and destroyed. Again it's of two types: (i) Automatic Storage Duration (for variables having Local or Block scope). (ii) Static Storage Duration (for variables having Global Scope or local variables (in a function or a in a code block) with static specifier).

3. Linkage: Determines whether a variable can be accessed (or linked ) in another file. Again ( and luckily) it is of two types: (i) Internal Linkage (for variables having Block Scope and Global Scope/File Scope/Global Namespace scope) (ii) External Linkage (for variables having only for Global Scope/File Scope/Global Namespace Scope)

Let's refer an example below for better understanding of plain global and local variables (no local variables with static storage duration) :

//main file
#include <iostream>

int global_var1; //has global scope
const global_var2(1.618); //has global scope

int main()
{
//these variables are local to the block main.
//they have automatic duration, i.e, they are created when the main() is 
//  executed and destroyed, when main goes out of scope
 int local_var1(23);
 const double local_var2(3.14);

 {
/* this is yet another block, all variables declared within this block are 
 have local scope limited within this block. */
// all variables declared within this block too have automatic duration, i.e, 
/*they are created at the point of definition within this block,
 and destroyed as soon as this block ends */
   char block_char1;
   int local_var1(32) //NOTE: this has been re-declared within the block, 
//it shadows the local_var1 declared outside

 std::cout << local_var1 <<"\n"; //prints 32

  }//end of block
  //local_var1 declared inside goes out of scope

 std::cout << local_var1 << "\n"; //prints 23

 global_var1 = 29; //global_var1 has been declared outside main (global scope)
 std::cout << global_var1 << "\n"; //prints 29
 std::cout << global_var2 << "\n"; //prints 1.618

 return 0;
}  //local_var1, local_var2 go out of scope as main ends
//global_var1, global_var2 go out of scope as the program terminates 
//(in this case program ends with end of main, so both local and global
//variable go out of scope together

Now comes the concept of Linkage. When a global variable defined in one file is intended to be used in another file, the linkage of the variable plays an important role.

The Linkage of global variables is specified by the keywords: (i) static , and, (ii) extern

( Now you get the explanation )

static keyword can be applied to variables with local and global scope, and in both the cases, they mean different things. I will first explain the usage of 'static' keyword in variables with global scope ( where I also clarify the usage of keyword 'extern') and later the for those with local scope.

1. Static Keyword for variables with global scope

Global variables have static duration, meaning they don't go out of scope when a particular block of code (for e.g main() ) in which it is used ends . Depending upon the linkage, they can be either accessed only within the same file where they are declared (for static global variable), or outside the file even outside the file in which they are declared (extern type global variables)

In the case of a global variable having extern specifier, and if this variable is being accessed outside the file in which it has been initialized, it has to be forward declared in the file where it's being used, just like a function has to be forward declared if it's definition is in a file different from where it's being used.

In contrast, if the global variable has static keyword, it cannot be used in a file outside of which it has been declared.

(see example below for clarification)

eg:

//main2.cpp
 static int global_var3 = 23;  /*static global variable, cannot be                            
                                accessed in anyother file */
 extern double global_var4 = 71; /*can be accessed outside this file                  linked to main2.cpp */
 int main() { return 0; }

main3.cpp

//main3.cpp
#include <iostream>

int main()
{
   extern int gloabl_var4; /*this variable refers to the gloabal_var4
                            defined in the main2.cpp file */
  std::cout << global_var4 << "\n"; //prints 71;

  return 0;
}

now any variable in c++ can be either a const or a non-const and for each 'const-ness' we get two case of default c++ linkage, in case none is specified:

(i) If a global variable is non-const, its linkage is extern by default, i.e, the non-const global variable can be accessed in another .cpp file by forward declaration using the extern keyword (in other words, non const global variables have external linkage ( with static duration of course)). Also usage of extern keyword in the original file where it has been defined is redundant. In this case to make a non-const global variable inaccessible to external file, use the specifier 'static' before the type of the variable.

(ii) If a global variable is const, its linkage is static by default, i.e a const global variable cannot be accessed in a file other than where it is defined, (in other words, const global variables have internal linkage (with static duration of course)). Also usage of static keyword to prevent a const global variable from being accessed in another file is redundant. Here, to make a const global variable have an external linkage, use the specifier 'extern' before the type of the variable

Here's a summary for global scope variables with various linkages

//globalVariables1.cpp 

// defining uninitialized vairbles
int globalVar1; //  uninitialized global variable with external linkage 
static int globalVar2; // uninitialized global variable with internal linkage
const int globalVar3; // error, since const variables must be initialized upon declaration
const int globalVar4 = 23; //correct, but with static linkage (cannot be accessed outside the file where it has been declared*/
extern const double globalVar5 = 1.57; //this const variable ca be accessed outside the file where it has been declared

Next we investigate how the above global variables behave when accessed in a different file.

//using_globalVariables1.cpp (eg for the usage of global variables above)

// Forward declaration via extern keyword:
 extern int globalVar1; // correct since globalVar1 is not a const or static
 extern int globalVar2; //incorrect since globalVar2 has internal linkage
 extern const int globalVar4; /* incorrect since globalVar4 has no extern 
                         specifier, limited to internal linkage by
                         default (static specifier for const variables) */
 extern const double globalVar5; /*correct since in the previous file, it 
                           has extern specifier, no need to initialize the
                       const variable here, since it has already been
                       legitimately defined perviously */

2. Static Keyword for variables with Local Scope

Updates (August 2019) on static keyword for variables in local scope

This further can be subdivided in two categories :

(i) static keyword for variables within a function block, and (ii) static keyword for variables within a unnamed local block.

(i) static keyword for variables within a function block.

Earlier, I mentioned that variables with local scope have automatic duration, i.e they come to exist when the block is entered ( be it a normal block, be it a function block) and cease to exist when the block ends, long story short, variables with local scope have automatic duration and automatic duration variables (and objects) have no linkage meaning they are not visible outside the code block.

If static specifier is applied to a local variable within a function block, it changes the duration of the variable from automatic to static and its life time is the entire duration of the program which means it has a fixed memory location and its value is initialized only once prior to program start up as mentioned in cpp reference(initialization should not be confused with assignment)

lets take a look at an example.

//localVarDemo1.cpp    
 int localNextID()
{
  int tempID = 1;  //tempID created here
  return tempID++; //copy of tempID returned and tempID incremented to 2
} //tempID destroyed here, hence value of tempID lost

int newNextID()
{
  static int newID = 0;//newID has static duration, with internal linkage
  return newID++; //copy of newID returned and newID incremented by 1
}  //newID doesn't get destroyed here :-)


int main()
{
  int employeeID1 = localNextID();  //employeeID1 = 1
  int employeeID2 = localNextID();  // employeeID2 = 1 again (not desired)
  int employeeID3 = newNextID(); //employeeID3 = 0;
  int employeeID4 = newNextID(); //employeeID4 = 1;
  int employeeID5 = newNextID(); //employeeID5 = 2;
  return 0;
}

Looking at the above criterion for static local variables and static global variables, one might be tempted to ask, what the difference between them could be. While global variables are accessible at any point in within the code (in same as well as different translation unit depending upon the const-ness and extern-ness), a static variable defined within a function block is not directly accessible. The variable has to be returned by the function value or reference. Lets demonstrate this by an example:

//localVarDemo2.cpp 

//static storage duration with global scope 
//note this variable can be accessed from outside the file
//in a different compilation unit by using `extern` specifier
//which might not be desirable for certain use case.
static int globalId = 0;

int newNextID()
{
  static int newID = 0;//newID has static duration, with internal linkage
  return newID++; //copy of newID returned and newID incremented by 1
}  //newID doesn't get destroyed here


int main()
{
    //since globalId is accessible we use it directly
  const int globalEmployee1Id = globalId++; //globalEmployeeId1 = 0;
  const int globalEmployee2Id = globalId++; //globalEmployeeId1 = 1;

  //const int employeeID1 = newID++; //this will lead to compilation error since newID++ is not accessible direcly. 
  int employeeID2 = newNextID(); //employeeID3 = 0;
  int employeeID2 = newNextID(); //employeeID3 = 1;

  return 0;
}

More explaination about choice of static global and static local variable could be found on this stackoverflow thread

(ii) static keyword for variables within a unnamed local block.

static variables within a local block (not a function block) cannot be accessed outside the block once the local block goes out of scope. No caveats to this rule.

    //localVarDemo3.cpp 
    int main()
    {

      {
          const static int static_local_scoped_variable {99};
      }//static_local_scoped_variable goes out of scope

      //the line below causes compilation error
      //do_something is an arbitrary function
      do_something(static_local_scoped_variable);
      return 0;
    }

C++11 introduced the keyword constexpr which guarantees the evaluation of an expression at compile time and allows compiler to optimize the code. Now if the value of a static const variable within a scope is known at compile time, the code is optimized in a manner similar to the one with constexpr. Here's a small example

I recommend readers also to look up the difference between constexprand static const for variables in this stackoverflow thread. this concludes my explanation for the static keyword applied to variables.

B. 'static' keyword used for functions

in terms of functions, the static keyword has a straightforward meaning. Here, it refers to linkage of the function Normally all functions declared within a cpp file have external linkage by default, i.e a function defined in one file can be used in another cpp file by forward declaration.

using a static keyword before the function declaration limits its linkage to internal , i.e a static function cannot be used within a file outside of its definition.

C. Staitc Keyword used for member variables and functions of classes

1. 'static' keyword for member variables of classes

I start directly with an example here

#include <iostream>

class DesignNumber
{
  private:

      static int m_designNum;  //design number
      int m_iteration;     // number of iterations performed for the design

  public:
    DesignNumber() {     }  //default constructor

   int  getItrNum() //get the iteration number of design
   {
      m_iteration = m_designNum++;
      return m_iteration;
   }
     static int m_anyNumber;  //public static variable
};
int DesignNumber::m_designNum = 0; // starting with design id = 0
                     // note : no need of static keyword here
                     //causes compiler error if static keyword used
int DesignNumber::m_anyNumber = 99; /* initialization of inclass public 
                                    static member  */
enter code here

int main()
{
   DesignNumber firstDesign, secondDesign, thirdDesign;
   std::cout << firstDesign.getItrNum() << "\n";  //prints 0
   std::cout << secondDesign.getItrNum() << "\n"; //prints 1
   std::cout << thirdDesign.getItrNum() << "\n";  //prints 2

   std::cout << DesignNumber::m_anyNumber++ << "\n";  /* no object
                                        associated with m_anyNumber */
   std::cout << DesignNumber::m_anyNumber++ << "\n"; //prints 100
   std::cout << DesignNumber::m_anyNumber++ << "\n"; //prints 101

   return 0;
}

In this example, the static variable m_designNum retains its value and this single private member variable (because it's static) is shared b/w all the variables of the object type DesignNumber

Also like other member variables, static member variables of a class are not associated with any class object, which is demonstrated by the printing of anyNumber in the main function

const vs non-const static member variables in class

(i) non-const class static member variables In the previous example the static members (both public and private) were non constants. ISO standard forbids non-const static members to be initialized in the class. Hence as in previous example, they must be initalized after the class definition, with the caveat that the static keyword needs to be omitted

(ii) const-static member variables of class this is straightforward and goes with the convention of other const member variable initialization, i.e the const static member variables of a class can be initialized at the point of declaration and they can be initialized at the end of the class declaration with one caveat that the keyword const needs to be added to the static member when being initialized after the class definition.

I would however, recommend to initialize the const static member variables at the point of declaration. This goes with the standard C++ convention and makes the code look cleaner

for more examples on static member variables in a class look up the following link from learncpp.com http://www.learncpp.com/cpp-tutorial/811-static-member-variables/

2. 'static' keyword for member function of classes

Just like member variables of classes can ,be static, so can member functions of classes. Normal member functions of classes are always associated with a object of the class type. In contrast, static member functions of a class are not associated with any object of the class, i.e they have no *this pointer.

Secondly since the static member functions of the class have no *this pointer, they can be called using the class name and scope resolution operator in the main function (ClassName::functionName(); )

Thirdly static member functions of a class can only access static member variables of a class, since non-static member variables of a class must belong to a class object.

for more examples on static member functions in a class look up the following link from learncpp.com

http://www.learncpp.com/cpp-tutorial/812-static-member-functions/

How to SELECT the last 10 rows of an SQL table which has no ID field?

If you have not tried the following command

SELECT TOP 10 * FROM big_table ORDER BY id DESC;

I see it's working when I execute the command

SELECT TOP 10 * FROM Customers ORDER BY CustomerId DESC;

in the Try it yourself command window of https://www.w3schools.com/sql/sql_func_last.asp