Programs & Examples On #Boost mpl

The Boost.MPL library is a general-purpose, high-level C++ template metaprogramming framework of compile-time algorithms, sequences and metafunctions. It provides a conceptual foundation and an extensive set of powerful and coherent tools that make doing explicit metaprogramming in C++ as easy and enjoyable as possible within the current language.

How to override maven property in command line?

See Introduction to the POM

finalName is created as:

<build>
    <finalName>${project.artifactId}-${project.version}</finalName>
</build>

One of the solutions is to add own property:

<properties>
    <finalName>${project.artifactId}-${project.version}</finalName>
</properties>
<build>
    <finalName>${finalName}</finalName>
 </build>

And now try:

mvn -DfinalName=build clean package

How do I install ASP.NET MVC 5 in Visual Studio 2012?

If you want to install ASP.NET MVC 5 and ASP.NET Web API 2 into VS 2012 Ultimage so, you can download MSI installer from
http://www.microsoft.com/en-us/download/details.aspx?id=41532.

I have downloaded and intalled just know. I got MVC 5 and Web API 2
:)

Assigning the output of a command to a variable

Try:

output=$(ps -ef | awk '/siebsvc –s siebsrvr/ && !/awk/ { a++ } END { print a }'); echo $output

Wrapping your command in $( ) tells the shell to run that command, instead of attempting to set the command itself to the variable named "output". (Note that you could also use backticks `command`.)

I can highly recommend http://tldp.org/LDP/abs/html/commandsub.html to learn more about command substitution.

Also, as 1_CR correctly points out in a comment, the extra space between the equals sign and the assignment is causing it to fail. Here is a simple example on my machine of the behavior you are experiencing:

jed@MBP:~$ foo=$(ps -ef |head -1);echo $foo
UID PID PPID C STIME TTY TIME CMD

jed@MBP:~$ foo= $(ps -ef |head -1);echo $foo
-bash: UID: command not found
UID PID PPID C STIME TTY TIME CMD

Wait on the Database Engine recovery handle failed. Check the SQL server error log for potential causes

Root cause: Corrupted user profile of user account used to start database

The main thread here seems to be a corrupted user account profile for the account that is used to start the DB engine. This is the account that was specified for the "SQL Server Database" engine during installation. In the setup event log, it's also indicated by the following entry:

SQLSVCACCOUNT:                 NT AUTHORITY\SYSTEM

According to the link provided by @royki:

The root cause of this issue, in most cases, is that the profile of the user being used for the service account (in my case it was local system) is corrupted.

This would explain why other respondents had success after changing to different accounts:

  • bmjjr suggests changing to "NT AUTHORITY\NETWORK SERVICE"
  • comments to @bmjjr indicate different accounts "I used NT AUTHORITY\LOCAL SERVICE. That helped too"
  • @Julio Nobre had success with "NT Authority\System "

Fix: reset the corrupt user profile

To fix the user profile that's causing the error, follow the steps listed KB947215.

The main steps from KB947215 are summarized as follows:-

  1. Open regedit
  2. Navigate to HKEY_LOCAL_MACHINE\SOFTWARE\Microsoft\Windows NT\CurrentVersion\ProfileList
  3. Navigate to the SID for the corrupted profile

    To find the SID, click on each SID GUID, review the value for the ProfileImagePath value, and see if it's the correct account. For system accounts, there's a different way to know the SID for the account that failed:

The main system account SIDs of interest are:

SID          Name               Also Known As
S-1-5-18     Local System       NT AUTHORITY\SYSTEM
S-1-5-19     LocalService       NT AUTHORITY\LOCAL SERVICE
S-1-5-20     NetworkService     NT AUTHORITY\NETWORK SERVICE

For information on additional SIDs, see Well-known security identifiers in Windows operating systems.

  1. If there are two entries (e.g. with a .bak) at the end for the SID in question, or the SID in question ends in .bak, ensure to follow carefully the steps in the KB947215 article.
  2. Reset the values for RefCount and State to be 0.
  3. Reboot.
  4. Retry the SQL Server installation.

How do I convert a String to an int in Java?

Integer.decode

You can also use public static Integer decode(String nm) throws NumberFormatException.

It also works for base 8 and 16:

// base 10
Integer.parseInt("12");     // 12 - int
Integer.valueOf("12");      // 12 - Integer
Integer.decode("12");       // 12 - Integer
// base 8
// 10 (0,1,...,7,10,11,12)
Integer.parseInt("12", 8);  // 10 - int
Integer.valueOf("12", 8);   // 10 - Integer
Integer.decode("012");      // 10 - Integer
// base 16
// 18 (0,1,...,F,10,11,12)
Integer.parseInt("12",16);  // 18 - int
Integer.valueOf("12",16);   // 18 - Integer
Integer.decode("#12");      // 18 - Integer
Integer.decode("0x12");     // 18 - Integer
Integer.decode("0X12");     // 18 - Integer
// base 2
Integer.parseInt("11",2);   // 3 - int
Integer.valueOf("11",2);    // 3 - Integer

If you want to get int instead of Integer you can use:

  1. Unboxing:

    int val = Integer.decode("12"); 
    
  2. intValue():

    Integer.decode("12").intValue();
    

How to run a class from Jar which is not the Main-Class in its Manifest file

You can create your jar without Main-Class in its Manifest file. Then :

java -cp MyJar.jar com.mycomp.myproj.dir2.MainClass2 /home/myhome/datasource.properties /home/myhome/input.txt

How to set the min and max height or width of a Frame?

There is no single magic function to force a frame to a minimum or fixed size. However, you can certainly force the size of a frame by giving the frame a width and height. You then have to do potentially two more things: when you put this window in a container you need to make sure the geometry manager doesn't shrink or expand the window. Two, if the frame is a container for other widget, turn grid or pack propagation off so that the frame doesn't shrink or expand to fit its own contents.

Note, however, that this won't prevent you from resizing a window to be smaller than an internal frame. In that case the frame will just be clipped.

import Tkinter as tk

root = tk.Tk()
frame1 = tk.Frame(root, width=100, height=100, background="bisque")
frame2 = tk.Frame(root, width=50, height = 50, background="#b22222")

frame1.pack(fill=None, expand=False)
frame2.place(relx=.5, rely=.5, anchor="c")

root.mainloop()

How to import jquery using ES6 syntax?

Based on the solution of Édouard Lopez, but in two lines:

import jQuery from "jquery";
window.$ = window.jQuery = jQuery;

How do I print the full value of a long string in gdb?

There is a third option: the x command, which allows you to set a different limit for the specific command instead of changing a global setting. To print the first 300 characters of a string you can use x/300s your_string. The output might be a bit harder to read. For example printing a SQL query results in:

(gdb) x/300sb stmt.c_str()
0x9cd948:    "SELECT article.r"...
0x9cd958:    "owid FROM articl"...
..

Socket File "/var/pgsql_socket/.s.PGSQL.5432" Missing In Mountain Lion (OS X Server)

File permissions are restrictive on the Postgres db owned by the Mac OS. These permissions are reset after reboot, or restart of Postgres: e.g. serveradmin start postgres.

So, temporarily reset the permissions or ownership:

sudo chmod o+rwx /var/pgsql_socket/.s.PGSQL.5432
sudo chown "webUser"  /var/pgsql_socket/.s.PGSQL.5432

Permissions resetting is not secure, so install a version of the db that you own for a solution.

how to rename an index in a cluster?

Just in case someone still needs it. The successful, not official, way to rename indexes are:

  1. Close indexes that need to be renamed
  2. Rename indexes' folders in all data directories of master and data nodes.
  3. Reopen old closed indexes (I use kofp plugin). Old indexes will be reopened but stay unassigned. New indexes will appear in closed state
  4. Reopen new indexes
  5. Delete old indexes

If you happen to get this error "dangled index directory name is", remove index folder in all master nodes (not data nodes), and restart one of the data nodes.

Simple DatePicker-like Calendar

I'm particularly fond of this date picker built for Mootools: http://electricprism.com/aeron/calendar/

It's lovely right out of the box.

Basic HTTP authentication with Node and Express 4

There seems to be multiple modules to do that, some are deprecated.

This one looks active:
https://github.com/jshttp/basic-auth

Here's a use example:

// auth.js

var auth = require('basic-auth');

var admins = {
  '[email protected]': { password: 'pa$$w0rd!' },
};


module.exports = function(req, res, next) {

  var user = auth(req);
  if (!user || !admins[user.name] || admins[user.name].password !== user.pass) {
    res.set('WWW-Authenticate', 'Basic realm="example"');
    return res.status(401).send();
  }
  return next();
};




// app.js

var auth = require('./auth');
var express = require('express');

var app = express();

// ... some not authenticated middlewares

app.use(auth);

// ... some authenticated middlewares

Make sure you put the auth middleware in the correct place, any middleware before that will not be authenticated.

How do I install a color theme for IntelliJ IDEA 7.0.x

Step 1: Do File -> Import Settings... and select the settings jar file

Step 2: Go to Settings -> Editor -> Colors and Fonts to choose the theme you just installed.

How do I find out where login scripts live?

In addition from the command prompt run SET.

This displayed the "LOGONSERVER" value which indicates the specific domain controller you are using (there can be more than one).

Then you got to that server's NetBios Share \Servername\SYSVOL\domain.local\scripts.

Understanding string reversal via slicing

[::-1] gives a slice of the string a. the full syntax is a[begin:end:step] which gives a[begin], a[begin+step], ... a[end-1]. WHen step is negative, you start at end and move to begin.

Finally, begin defaults to the beginning of the sequence, end to the end, and step to -1.

How to reshape data from long to wide format

With the devel version of tidyr ‘0.8.3.9000’, there is pivot_wider and pivot_longer which is generalized to do the reshaping (long -> wide, wide -> long, respectively) from 1 to multiple columns. Using the OP's data

-single column long -> wide

library(dplyr)
library(tidyr)
dat1 %>% 
    pivot_wider(names_from = numbers, values_from = value)
# A tibble: 2 x 5
#  name          `1`    `2`    `3`    `4`
#  <fct>       <dbl>  <dbl>  <dbl>  <dbl>
#1 firstName   0.341 -0.703 -0.380 -0.746
#2 secondName -0.898 -0.335 -0.501 -0.175

-> created another column for showing the functionality

dat1 %>% 
    mutate(value2 = value * 2) %>% 
    pivot_wider(names_from = numbers, values_from = c("value", "value2"))
# A tibble: 2 x 9
#  name       value_1 value_2 value_3 value_4 value2_1 value2_2 value2_3 value2_4
#  <fct>        <dbl>   <dbl>   <dbl>   <dbl>    <dbl>    <dbl>    <dbl>    <dbl>
#1 firstName    0.341  -0.703  -0.380  -0.746    0.682   -1.41    -0.759   -1.49 
#2 secondName  -0.898  -0.335  -0.501  -0.175   -1.80    -0.670   -1.00    -0.349

How to avoid the "divide by zero" error in SQL?

You can handle the error appropriately when it propagates back to the calling program (or ignore it if that's what you want). In C# any errors that occur in SQL will throw an exception that I can catch and then handle in my code, just like any other error.

I agree with Beska in that you do not want to hide the error. You may not be dealing with a nuclear reactor but hiding errors in general is bad programming practice. This is one of the reasons most modern programming languages implement structured exception handling to decouple the actual return value with an error / status code. This is especially true when you are doing math. The biggest problem is that you cannot distinguish between a correctly computed 0 being returned or a 0 as the result of an error. Instead any value returned is the computed value and if anything goes wrong an exception is thrown. This will of course differ depending on how you are accessing the database and what language you are using but you should always be able to get an error message that you can deal with.

try
{
    Database.ComputePercentage();
}
catch (SqlException e)
{
    // now you can handle the exception or at least log that the exception was thrown if you choose not to handle it
    // Exception Details: System.Data.SqlClient.SqlException: Divide by zero error encountered.
}

A cron job for rails: best practices?

I use backgroundrb.

http://backgroundrb.rubyforge.org/

I use it to run scheduled tasks as well as tasks that take too long for the normal client/server relationship.

Extracting Nupkg files using command line

With PowerShell 5.1 (PackageManagement module)

Install-Package -Name MyPackage -Source (Get-Location).Path -Destination C:\outputdirectory

What is a quick way to force CRLF in C# / .NET?

This is a quick way to do that, I mean.

It does not use an expensive regex function. It also does not use multiple replacement functions that each individually did loop over the data with several checks, allocations, etc.

So the search is done directly in one for loop. For the number of times that the capacity of the result array has to be increased, a loop is also used within the Array.Copy function. That are all the loops. In some cases, a larger page size might be more efficient.

public static string NormalizeNewLine(this string val)
{
    if (string.IsNullOrEmpty(val))
        return val;

    const int page = 6;
    int a = page;
    int j = 0;
    int len = val.Length;
    char[] res = new char[len];

    for (int i = 0; i < len; i++)
    {
        char ch = val[i];

        if (ch == '\r')
        {
            int ni = i + 1;
            if (ni < len && val[ni] == '\n')
            {
                res[j++] = '\r';
                res[j++] = '\n';
                i++;
            }
            else
            {
                if (a == page) // Ensure capacity
                {
                    char[] nres = new char[res.Length + page];
                    Array.Copy(res, 0, nres, 0, res.Length);
                    res = nres;
                    a = 0;
                }

                res[j++] = '\r';
                res[j++] = '\n';
                a++;
            }
        }
        else if (ch == '\n')
        {
            int ni = i + 1;
            if (ni < len && val[ni] == '\r')
            {
                res[j++] = '\r';
                res[j++] = '\n';
                i++;
            }
            else
            {
                if (a == page) // Ensure capacity
                {
                    char[] nres = new char[res.Length + page];
                    Array.Copy(res, 0, nres, 0, res.Length);
                    res = nres;
                    a = 0;
                }

                res[j++] = '\r';
                res[j++] = '\n';
                a++;
            }
        }
        else
        {
            res[j++] = ch;
        }
    }

    return new string(res, 0, j);
}

I now that '\n\r' is not actually used on basic platforms. But who would use two types of linebreaks in succession to indicate two linebreaks?

If you want to know that, then you need to take a look before to know if the \n and \r both are used separately in the same document.

How can I color dots in a xy scatterplot according to column value?

Non-VBA Solution:

You need to make an additional group of data for each color group that represent the Y values for that particular group. You can use these groups to make multiple data sets within your graph.

Here is an example using your data:

     A       B        C        D                    E                        F                            G
----------------------------------------------------------------------------------------------------------------------
1| COMPANY  XVALUE   YVALUE   GROUP                 Red                     Orange                       Green
2| Apple     45       35       red         =IF($D2="red",$C2,NA()) =IF($D2="orange",$C2,NA()) =IF($D2="green",$C2,NA())
3| Xerox     45       38       red         =IF($D3="red",$C3,NA()) =IF($D3="orange",$C3,NA()) =IF($D3="green",$C3,NA())
4| KMart     63       50       orange      =IF($D4="red",$C4,NA()) =IF($D4="orange",$C4,NA()) =IF($D4="green",$C4,NA())
5| Exxon     53       59       green       =IF($D5="red",$C5,NA()) =IF($D5="orange",$C5,NA()) =IF($D5="green",$C5,NA())

It should look like this afterwards:

     A       B        C        D          E           F          G
---------------------------------------------------------------------
1| COMPANY  XVALUE   YVALUE   GROUP       Red         Orange     Green
2| Apple     45       35       red         35         #N/A       #N/A    
3| Xerox     45       38       red         38         #N/A       #N/A
4| KMart     63       50       orange     #N/A         50        #N/A
5| Exxon     53       59       green      #N/a        #N/A        59

Now you can generate your graph using different data sets. Here is a picture showing just this example data:

enter image description here

You can change the series (X;Y) values to B:B ; E:E, B:B ; F:F, B:B ; G:G respectively, to make it so the graph is automatically updated when you add more data.

Change Activity's theme programmatically

user1462299's response works great, but if you include fragments, they will use the original activities theme. To apply the theme to all fragments as well you can override the getTheme() method of the Context instead:

@Override
public Resources.Theme getTheme() {
    Resources.Theme theme = super.getTheme();
    if(useAlternativeTheme){
        theme.applyStyle(R.style.AlternativeTheme, true);
    }
    // you could also use a switch if you have many themes that could apply
    return theme;
}

You do not need to call setTheme() in the onCreate() Method anymore. You are overriding every request to get the current theme within this context this way.

Detect click outside Angular component

ginalx's answer should be set as the default one imo: this method allows for many optimizations.

The problem

Say that we have a list of items and on every item we want to include a menu that needs to be toggled. We include a toggle on a button that listens for a click event on itself (click)="toggle()", but we also want to toggle the menu whenever the user clicks outside of it. If the list of items grows and we attach a @HostListener('document:click') on every menu, then every menu loaded within the item will start listening for the click on the entire document, even when the menu is toggled off. Besides the obvious performance issues, this is unnecessary.

You can, for example, subscribe whenever the popup gets toggled via a click and start listening for "outside clicks" only then.


isActive: boolean = false;

// to prevent memory leaks and improve efficiency, the menu
// gets loaded only when the toggle gets clicked
private _toggleMenuSubject$: BehaviorSubject<boolean>;
private _toggleMenu$: Observable<boolean>;

private _toggleMenuSub: Subscription;
private _clickSub: Subscription = null;


constructor(
 ...
 private _utilitiesService: UtilitiesService,
 private _elementRef: ElementRef,
){
 ...
 this._toggleMenuSubject$ = new BehaviorSubject(false);
 this._toggleMenu$ = this._toggleMenuSubject$.asObservable();

}

ngOnInit() {
 this._toggleMenuSub = this._toggleMenu$.pipe(
      tap(isActive => {
        logger.debug('Label Menu is active', isActive)
        this.isActive = isActive;

        // subscribe to the click event only if the menu is Active
        // otherwise unsubscribe and save memory
        if(isActive === true){
          this._clickSub = this._utilitiesService.documentClickedTarget
           .subscribe(target => this._documentClickListener(target));
        }else if(isActive === false && this._clickSub !== null){
          this._clickSub.unsubscribe();
        }

      }),
      // other observable logic
      ...
      ).subscribe();
}

toggle() {
    this._toggleMenuSubject$.next(!this.isActive);
}

private _documentClickListener(targetElement: HTMLElement): void {
    const clickedInside = this._elementRef.nativeElement.contains(targetElement);
    if (!clickedInside) {
      this._toggleMenuSubject$.next(false);
    }    
 }

ngOnDestroy(){
 this._toggleMenuSub.unsubscribe();
}

And, in *.component.html:


<button (click)="toggle()">Toggle the menu</button>

Pass array to MySQL stored routine

I've come up with an awkward but functional solution for my problem. It works for a one-dimensional array (more dimensions would be tricky) and input that fits into a varchar:

  declare pos int;           -- Keeping track of the next item's position
  declare item varchar(100); -- A single item of the input
  declare breaker int;       -- Safeguard for while loop 

  -- The string must end with the delimiter
  if right(inputString, 1) <> '|' then
     set inputString = concat(inputString, '|');
  end if;

  DROP TABLE IF EXISTS MyTemporaryTable;
  CREATE TEMPORARY TABLE MyTemporaryTable ( columnName varchar(100) );
  set breaker = 0;

  while (breaker < 2000) && (length(inputString) > 1) do
     -- Iterate looking for the delimiter, add rows to temporary table.
     set breaker = breaker + 1;
     set pos = INSTR(inputString, '|');
     set item = LEFT(inputString, pos - 1);
     set inputString = substring(inputString, pos + 1);
     insert into MyTemporaryTable values(item);
  end while;

For example, input for this code could be the string Apple|Banana|Orange. MyTemporaryTable will be populated with three rows containing the strings Apple, Banana, and Orange respectively.

I thought the slow speed of string handling would render this approach useless, but it was quick enough (only a fraction of a second for a 1,000 entries array).

Hope this helps somebody.

Java: how can I split an ArrayList in multiple small ArrayLists?

Create a new list and add a sublist view of the source list using the addAll() method to create a new sublist

List<T> newList = new ArrayList<T>();
newList.addAll(sourceList.subList(startIndex, endIndex));

Make Adobe fonts work with CSS3 @font-face in IE9

You can solve it by following code

@font-face {
  font-family: 'Font-Name';
  src: url('../fonts/Font-Name.ttf');
  src: url('../fonts/Font-Name.eot?#iefix') format('embedded-opentype');
}

GridView sorting: SortDirection always Ascending

To toggle ascending and descending, I use a method in my app's BasePage to cache the sort expression and sort direction:

protected void SetPageSort(GridViewSortEventArgs e)
{
    if (e.SortExpression == SortExpression)
    {
        if (SortDirection == "ASC")
        {
            SortDirection = "DESC";
        }
        else
        {
            SortDirection = "ASC";
        }
    }
    else
    {
        SortDirection = "ASC";
        SortExpression = e.SortExpression;
    }
}

SortExpression and SortDirection are both properties in BasePage that store and retrieve their values from ViewState.

So all of my derived pages just call SetPageSort from the GridView's Sorting method, and bind the GridView:

protected void gv_Sorting(object sender, GridViewSortEventArgs e)
{
    SetPageSort(e);
    BindGrid();
}

BindGrid checks the SortExpression and uses it and SortDirection to do an ORDERY BY on the grid's data source, something like this:

if (SortExpression.Length > 0)
{
    qry.ORDER_BY(SortExpression + " " + SortDirection);
}

gv.DataSource = qry.ExecuteReader();
gv.DataBind();

So, the base class' SetPageSort removes much of the drudgery of GridView sorting. I feel like I'm forgetting something, but that's the general idea.

C# Syntax - Example of a Lambda Expression - ForEach() over Generic List

public static void Each<T>(this IEnumerable<T> items, Action<T> action) {
foreach (var item in items) {
    action(item);
} }

... and call it thusly:

myList.Each(x => { x.Enabled = false; });

Can't ignore UserInterfaceState.xcuserstate

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

first you can create a .gitignore file by using

 touch .gitignore

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

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

Vim clear last search highlighting

This is what I use (extracted from a lot of different questions/answers):

nnoremap <silent> <Esc><Esc> :let @/=""<CR>

With "double" Esc you remove the highlighting, but as soon as you search again, the highlighting reappears.


Another alternative:

nnoremap <silent> <Esc><Esc> :noh<CR> :call clearmatches()<CR>

According to vim documentation:

clearmatches()

    Clears all matches previously defined by |matchadd()| and the

    |:match| commands.

How to trim a list in Python

l = [4,76,2,8,6,4,3,7,2,1]
l = l[:5]

How to stick a footer to bottom in css?

Assuming you know the size of your footer, you can do this:

    footer {
        position: sticky;
        height: 100px;
        top: calc( 100vh - 100px );
    }

Cannot find Microsoft.Office.Interop Visual Studio

You need to install Visual Studio Tools for Office Runtime Redistributable:

http://msdn.microsoft.com/en-us/library/ms178739.aspx

How to Export Private / Secret ASC Key to Decrypt GPG Files

1.Export a Secret Key (this is what your boss should have done for you)

gpg --export-secret-keys yourKeyName > privateKey.asc

2.Import Secret Key (import your privateKey)

gpg --import privateKey.asc

3.Not done yet, you still need to ultimately trust a key. You will need to make sure that you also ultimately trust a key.

gpg --edit-key yourKeyName

Enter trust, 5, y, and then quit

Source: https://medium.com/@GalarnykMichael/public-key-asymmetric-cryptography-using-gpg-5a8d914c9bca

log4j:WARN No appenders could be found for logger (running jar file, not web app)

You will find de log4j.properties in solr/examples/resources.

If you don't find the file, i put it here:

#  Logging level
solr.log=logs/
log4j.rootLogger=INFO, file, CONSOLE

log4j.appender.CONSOLE=org.apache.log4j.ConsoleAppender

log4j.appender.CONSOLE.layout=org.apache.log4j.PatternLayout
log4j.appender.CONSOLE.layout.ConversionPattern=%-4r [%t] %-5p %c %x \u2013 %m%n

#- size rotation with log cleanup.
log4j.appender.file=org.apache.log4j.RollingFileAppender
log4j.appender.file.MaxFileSize=4MB
log4j.appender.file.MaxBackupIndex=9

#- File to log to and log format
log4j.appender.file.File=${solr.log}/solr.log
log4j.appender.file.layout=org.apache.log4j.PatternLayout
log4j.appender.file.layout.ConversionPattern=%-5p - %d{yyyy-MM-dd HH:mm:ss.SSS}; %C; %m\n

log4j.logger.org.apache.zookeeper=WARN
log4j.logger.org.apache.hadoop=WARN

# set to INFO to enable infostream log messages
log4j.logger.org.apache.solr.update.LoggingInfoStream=OFF

Regards

How to use Redirect in the new react-router-dom of Reactjs

Hi if you are using react-router v-6.0.0-beta or V6 in This version Redirect Changes to Navigate like this

import { Navigate } from 'react-router-dom'; // like this CORRECT in v6 import { Redirect } from 'react-router-dom'; // like this CORRECT in v5

import { Redirect } from 'react-router-dom'; // like this WRONG in v6 // This will give you error in V6 of react-router and react-router dom

please make sure use both same version in package.json { "react-router": "^6.0.0-beta.0", //Like this "react-router-dom": "^6.0.0-beta.0", // like this }

this above things only works well in react Router Version 6

How to jump to a particular line in a huge text file?

If you know in advance the position in the file (rather the line number), you can use file.seek() to go to that position.

Edit: you can use the linecache.getline(filename, lineno) function, which will return the contents of the line lineno, but only after reading the entire file into memory. Good if you're randomly accessing lines from within the file (as python itself might want to do to print a traceback) but not good for a 15MB file.

How to create Password Field in Model Django

I thinks it is vary helpful way.

models.py

from django.db import models
class User(models.Model):
    user_name = models.CharField(max_length=100)
    password = models.CharField(max_length=32)

forms.py

from django import forms
from Admin.models import *
class User_forms(forms.ModelForm):
    class Meta:
        model= User
        fields=[
           'user_name',
           'password'
            ]
       widgets = {
      'password': forms.PasswordInput()
         }

Auto reloading python Flask app upon code changes

Flask applications can optionally be executed in debug mode. In this mode, two very convenient modules of the development server called the reloader and the debugger are enabled by default. When the reloader is enabled, Flask watches all the source code files of your project and automatically restarts the server when any of the files are modified.

By default, debug mode is disabled. To enable it, set a FLASK_DEBUG=1 environment variable before invoking flask run:

(venv) $ export FLASK_APP=hello.py for Windows use > set FLASK_APP=hello.py

(venv) $ export FLASK_DEBUG=1 for Windows use > set FLASK_DEBUG=1

(venv) $ flask run

* Serving Flask app "hello"
* Forcing debug mode on
* Running on http://127.0.0.1:5000/ (Press CTRL+C to quit)
* Restarting with stat
* Debugger is active!
* Debugger PIN: 273-181-528

Having a server running with the reloader enabled is extremely useful during development, because every time you modify and save a source file, the server automatically restarts and picks up the change.

How do I create a comma delimited string from an ArrayList?

So far I found this is a good and quick solution

//CPID[] is the array
string cps = "";
if (CPID.Length > 0)
{   
    foreach (var item in CPID)
    {
        cps += item.Trim() + ",";
    }
}
//Use the string cps

Capture the Screen into a Bitmap

Bitmap memoryImage;
//Set full width, height for image
memoryImage = new Bitmap(Screen.PrimaryScreen.Bounds.Width,
                       Screen.PrimaryScreen.Bounds.Height,
                       PixelFormat.Format32bppArgb);
Size s = new Size(memoryImage.Width, memoryImage.Height);
Graphics memoryGraphics = Graphics.FromImage(memoryImage);
memoryGraphics.CopyFromScreen(0, 0, 0, 0, s);
string str = "";
try
{
    str = string.Format(Environment.GetFolderPath(Environment.SpecialFolder.MyDocuments) +
          @"\Screenshot.png");//Set folder to save image
}
catch { };
memoryImage.save(str);

how to set ASPNETCORE_ENVIRONMENT to be considered for publishing an asp.net core application?

With the latest version of dotnet cli (2.1.400 or greater), you can just set this msbuild property $(EnvironmentName) and publish tooling will take care of adding ASPNETCORE_ENVIRONMENT to the web.config with the environment name.

Also, XDT support is available starting 2.2.100-preview1.

Sample: https://github.com/vijayrkn/webconfigtransform/blob/master/README.md

How to fix Array indexOf() in JavaScript for Internet Explorer browsers

Do it like this...

if (!Array.prototype.indexOf) {

}

As recommended compatibility by MDC.

In general, browser detection code is a big no-no.

How can I exclude multiple folders using Get-ChildItem -exclude?

I wanted a solution that didn't involve looping over every single item and doing ifs. Here's a solution that is just a simple recursive function over Get-ChildItem. We just loop and recurse over directories.


function Get-RecurseItem {
    [Cmdletbinding()]
    param (
        [Parameter(ValueFromPipeline=$true)][string]$Path,
        [string[]]$Exclude = @(),
        [string]$Include = '*'
    )
    Get-ChildItem -Path (Join-Path $Path '*') -Exclude $Exclude -Directory | ForEach-Object {
        @(Get-ChildItem -Path (Join-Path $_ '*') -Include $Include -Exclude $Exclude -File) + ``
        @(Get-RecurseItem -Path $_ -Include $Include -Exclude $Exclude)
    }
}

Why shouldn't I use "Hungarian Notation"?

If I feel that useful information is being imparted, why shouldn't I put it right there where it's available?

Then who cares what anybody else thinks? If you find it useful, then use the notation.

Can we have multiple "WITH AS" in single sql - Oracle SQL

Aditya or others, can you join or match up t2 with t1 in your example, i.e. translated to my code,

with t1 as (select * from AA where FIRSTNAME like 'Kermit'),
     t2 as (select * from BB B join t1 on t1.FIELD1 = B.FIELD1)

I am not clear whether only WHERE is supported for joining, or what joining approach is supported within the 2nd WITH entity. Some of the examples have the WHERE A=B down in the body of the select "below" the WITH clauses.

The error I'm getting following these WITH declarations is the identifiers (field names) in B are not recognized, down in the body of the rest of the SQL. So the WITH syntax seems to run OK, but cannot access the results from t2.

"Large data" workflows using pandas

I recently came across a similar issue. I found simply reading the data in chunks and appending it as I write it in chunks to the same csv works well. My problem was adding a date column based on information in another table, using the value of certain columns as follows. This may help those confused by dask and hdf5 but more familiar with pandas like myself.

def addDateColumn():
"""Adds time to the daily rainfall data. Reads the csv as chunks of 100k 
   rows at a time and outputs them, appending as needed, to a single csv. 
   Uses the column of the raster names to get the date.
"""
    df = pd.read_csv(pathlist[1]+"CHIRPS_tanz.csv", iterator=True, 
                     chunksize=100000) #read csv file as 100k chunks

    '''Do some stuff'''

    count = 1 #for indexing item in time list 
    for chunk in df: #for each 100k rows
        newtime = [] #empty list to append repeating times for different rows
        toiterate = chunk[chunk.columns[2]] #ID of raster nums to base time
        while count <= toiterate.max():
            for i in toiterate: 
                if i ==count:
                    newtime.append(newyears[count])
            count+=1
        print "Finished", str(chunknum), "chunks"
        chunk["time"] = newtime #create new column in dataframe based on time
        outname = "CHIRPS_tanz_time2.csv"
        #append each output to same csv, using no header
        chunk.to_csv(pathlist[2]+outname, mode='a', header=None, index=None)

SQL RANK() versus ROW_NUMBER()

Quite a bit:

The rank of a row is one plus the number of ranks that come before the row in question.

Row_number is the distinct rank of rows, without any gap in the ranking.

http://www.bidn.com/blogs/marcoadf/bidn-blog/379/ranking-functions-row_number-vs-rank-vs-dense_rank-vs-ntile

Selenium Webdriver move mouse to Point

Why use java.awt.Robot when org.openqa.selenium.interactions.Actions.class would probably work fine? Just sayin.

Actions builder = new Actions(driver);

builder.keyDown(Keys.CONTROL)
   .click(someElement)
   .moveByOffset( 10, 25 );
   .click(someOtherElement)
   .keyUp(Keys.CONTROL).build().perform();

C# Public Enums in Classes

Just declare the enum outside the bounds of the class. Like this:

public enum card_suits
{
    Clubs,
    Hearts,
    Spades,
    Diamonds
}

public class Card
{
    ...
}

Remember that an enum is a type. You might also consider putting the enum in its own file if it's going to be used by other classes. (You're programming a card game and the suit is a very important attribute of the card that, in well-structured code, will need to be accessible by a number of classes.)

How to create composite primary key in SQL Server 2008

For MSSQL Server 2012

CREATE TABLE usrgroup(
  usr_id int FOREIGN KEY REFERENCES users(id),
  grp_id int FOREIGN KEY REFERENCES groups(id),

  PRIMARY KEY (usr_id, grp_id)
)

UPDATE

I should add !

If you want to add foreign / primary keys altering, firstly you should create the keys with constraints or you can not make changes. Like this below:

CREATE TABLE usrgroup(
  usr_id int,
  grp_id int,

  CONSTRAINT FK_usrgroup_usrid FOREIGN KEY (usr_id) REFERENCES users(id),
  CONSTRAINT FK_usrgroup_groupid FOREIGN KEY (grp_id) REFERENCES groups(id),

  CONSTRAINT PK_usrgroup PRIMARY KEY (usr_id,grp_id)
)

Actually last way is healthier and serial. You can look the FK/PK Constraint names (dbo.dbname > Keys > ..) but if you do not use a constraint, MSSQL auto-creates random FK/PK names. You will need to look at every change (alter table) you need.

I recommend that you set a standard for yourself; the constraint should be defined according to the your standard. You will not have to memorize and you will not have to think too long. In short, you work faster.

Python Checking a string's first and last character

When you set a string variable, it doesn't save quotes of it, they are a part of its definition. so you don't need to use :1

set serveroutput on in oracle procedure

Procedure successful but any outpout

Error line1: Unexpected identifier

Here is the code:

SET SERVEROUTPUT ON 

DECLARE

    -- Curseurs 
    CURSOR c1 IS        
    SELECT RWID FROM J_EVT
     WHERE DT_SYST < TO_DATE(TO_CHAR(SYSDATE,'DD/MM') || '/' || TO_CHAR(TO_NUMBER(TO_CHAR(SYSDATE, 'YYYY')) - 3));

    -- Collections 

    TYPE tc1 IS TABLE OF c1%RWTYPE;

    -- Variables de type record
    rtc1                        tc1;    

    vCpt                        NUMBER:=0;

BEGIN

    OPEN c1;
    LOOP
        FETCH c1 BULK COLLECT INTO rtc1 LIMIT 5000;

        FORALL i IN 1..rtc1.COUNT 
        DELETE FROM J_EVT
          WHERE RWID = rtc1(i).RWID;
        COMMIT;

        -- Nombres lus : 5025651
        FOR i IN 1..rtc1.COUNT LOOP               
            vCpt := vCpt + SQL%BULK_RWCOUNT(i);
        END LOOP;            

        EXIT WHEN c1%NOTFOUND;   
    END LOOP;
    CLOSE c1;
    COMMIT;

    DBMS_OUTPUT.PUT_LINE ('Nombres supprimes : ' || TO_CHAR(vCpt)); 

END;
/
exit

Testing socket connection in Python

It seems that you catch not the exception you wanna catch out there :)

if the s is a socket.socket() object, then the right way to call .connect would be:

import socket
s = socket.socket()
address = '127.0.0.1'
port = 80  # port number is a number, not string
try:
    s.connect((address, port)) 
    # originally, it was 
    # except Exception, e: 
    # but this syntax is not supported anymore. 
except Exception as e: 
    print("something's wrong with %s:%d. Exception is %s" % (address, port, e))
finally:
    s.close()

Always try to see what kind of exception is what you're catching in a try-except loop.

You can check what types of exceptions in a socket module represent what kind of errors (timeout, unable to resolve address, etc) and make separate except statement for each one of them - this way you'll be able to react differently for different kind of problems.

Why isn't ProjectName-Prefix.pch created automatically in Xcode 6?

I suspect because of modules, which remove the need for the #import <Cocoa/Cocoa.h>.

As to where to put code that you would put in a prefix header, there is no code you should put in a prefix header. Put your imports into the files that need them. Put your definitions into their own files. Put your macros...nowhere. Stop writing macros unless there is no other way (such as when you need __FILE__). If you do need macros, put them in a header and include it.

The prefix header was necessary for things that are huge and used by nearly everything in the whole system (like Foundation.h). If you have something that huge and ubiquitous, you should rethink your architecture. Prefix headers make code reuse hard, and introduce subtle build problems if any of the files listed can change. Avoid them until you have a serious build time problem that you can demonstrate is dramatically improved with a prefix header.

In that case you can create one and pass it into clang, but it's incredibly rare that it's a good idea.


EDIT: To your specific question about a HUD you use in all your view controllers, yes, you should absolutely import it into every view controller that actually uses it. This makes the dependencies clear. When you reuse your view controller in a new project (which is common if you build your controllers well), you will immediately know what it requires. This is especially important for categories, which can make code very hard to reuse if they're implicit.

The PCH file isn't there to get rid of listing dependencies. You should still import UIKit.h or Foundation.h as needed, as the Xcode templates do. The reason for the PCH is to improve build times when dealing with really massive headers (like in UIKit).

How do I set up HttpContent for my HttpClient PostAsync second parameter?

    public async Task<ActionResult> Index()
    {
        apiTable table = new apiTable();
        table.Name = "Asma Nadeem";
        table.Roll = "6655";

        string str = "";
        string str2 = "";

        HttpClient client = new HttpClient();

        string json = JsonConvert.SerializeObject(table);

        StringContent httpContent = new StringContent(json, System.Text.Encoding.UTF8, "application/json");

        var response = await client.PostAsync("http://YourSite.com/api/apiTables", httpContent);

        str = "" + response.Content + " : " + response.StatusCode;

        if (response.IsSuccessStatusCode)
        {       
            str2 = "Data Posted";
        }

        return View();
    }

SVN undo delete before commit

1) do

svn revert . --recursive

2) parse output for errors like

"Failed to revert 'dir1/dir2' -- try updating instead."

3) call svn up for each of error directories:

svn up dir1/dir2

Guid.NewGuid() vs. new Guid()

Guid.NewGuid(), as it creates GUIDs as intended.

Guid.NewGuid() creates an empty Guid object, initializes it by calling CoCreateGuid and returns the object.

new Guid() merely creates an empty GUID (all zeros, I think).

I guess they had to make the constructor public as Guid is a struct.

How can I trigger a JavaScript event click

I'm quite ashamed that there are so many incorrect or undisclosed partial applicability.

The easiest way to do this is through Chrome or Opera (my examples will use Chrome) using the Console. Enter the following code into the console (generally in 1 line):

var l = document.getElementById('testLink');
for(var i=0; i<5; i++){
  l.click();
}

This will generate the required result

Apache error: _default_ virtualhost overlap on port 443

On a vanilla Apache2 install in CentOS, when you install mod_ssl it will automatically add a configuration file in:

{apache_dir}/conf.d/ssl.conf

This configuration file contains a default virtual host definition for port 443, named default:443. If you also have your own virtual host definition for 443 (i.e. in httpd.conf) then you will have a confict. Since the conf.d files are included first, they will win over yours.

To solve the conflict you can either remove the virtual host definition from conf.d/ssl.conf or update it to your own settings.

Find and replace string values in list

In case you're wondering about the performance of the different approaches, here are some timings:

In [1]: words = [str(i) for i in range(10000)]

In [2]: %timeit replaced = [w.replace('1', '<1>') for w in words]
100 loops, best of 3: 2.98 ms per loop

In [3]: %timeit replaced = map(lambda x: str.replace(x, '1', '<1>'), words)
100 loops, best of 3: 5.09 ms per loop

In [4]: %timeit replaced = map(lambda x: x.replace('1', '<1>'), words)
100 loops, best of 3: 4.39 ms per loop

In [5]: import re

In [6]: r = re.compile('1')

In [7]: %timeit replaced = [r.sub('<1>', w) for w in words]
100 loops, best of 3: 6.15 ms per loop

as you can see for such simple patterns the accepted list comprehension is the fastest, but look at the following:

In [8]: %timeit replaced = [w.replace('1', '<1>').replace('324', '<324>').replace('567', '<567>') for w in words]
100 loops, best of 3: 8.25 ms per loop

In [9]: r = re.compile('(1|324|567)')

In [10]: %timeit replaced = [r.sub('<\1>', w) for w in words]
100 loops, best of 3: 7.87 ms per loop

This shows that for more complicated substitutions a pre-compiled reg-exp (as in 9-10) can be (much) faster. It really depends on your problem and the shortest part of the reg-exp.

How do you use script variables in psql?

Another approach is to (ab)use the PostgreSQL GUC mechanism to create variables. See this prior answer for details and examples.

You declare the GUC in postgresql.conf, then change its value at runtime with SET commands and get its value with current_setting(...).

I don't recommend this for general use, but it could be useful in narrow cases like the one mentioned in the linked question, where the poster wanted a way to provide the application-level username to triggers and functions.

How to unzip a file in Powershell?

Here is a simple way using ExtractToDirectory from System.IO.Compression.ZipFile:

Add-Type -AssemblyName System.IO.Compression.FileSystem
function Unzip
{
    param([string]$zipfile, [string]$outpath)

    [System.IO.Compression.ZipFile]::ExtractToDirectory($zipfile, $outpath)
}

Unzip "C:\a.zip" "C:\a"

Note that if the target folder doesn't exist, ExtractToDirectory will create it. Other caveats:

See also:

How to convert int to float in C?

Change your code to:

int total=0, number=0;
float percentage=0.0f;

percentage=((float)number/total)*100f;
printf("%.2f", (double)percentage);

How to add text to JFrame?

To create a label for text:

JLabel label1 = new JLabel("Test");

To change the text in the label:

label1.setText("Label Text");

And finally to clear the label:

label1.setText("");

And all you have to do is place the label in your layout, or whatever layout system you are using, and then just add it to the JFrame...

Remove first 4 characters of a string with PHP

You could use the substr function to return a substring starting from the 5th character:

$str = "The quick brown fox jumps over the lazy dog."
$str2 = substr($str, 4); // "quick brown fox jumps over the lazy dog."

How to update all MySQL table rows at the same time?

update mytable set online_status = 'online'

If you want to assign different values, you should use the TRANSACTION technique.

How can I find whitespace in a String?

For checking if a string contains whitespace use a Matcher and call it's find method.

Pattern pattern = Pattern.compile("\\s");
Matcher matcher = pattern.matcher(s);
boolean found = matcher.find();

If you want to check if it only consists of whitespace then you can use String.matches:

boolean isWhitespace = s.matches("^\\s*$");

Java 32-bit vs 64-bit compatibility

The 32-bit vs 64-bit difference does become more important when you are interfacing with native libraries. 64-bit Java will not be able to interface with a 32-bit non-Java dll (via JNI)

how to configure hibernate config file for sql server

Finally this is for Hibernate 5 in Tomcat.

Compiled all the answers from the above and added my tips which works like a charm for Hibernate 5 and SQL Server 2014.

<hibernate-configuration>
<session-factory>
<property name="hibernate.dialect">
   org.hibernate.dialect.SQLServerDialect
</property>
<property name="hibernate.connection.driver_class">
   com.microsoft.sqlserver.jdbc.SQLServerDriver
</property>
<property name="hibernate.connection.url">  
jdbc:sqlserver://localhost\ServerInstanceOrServerName:1433;databaseName=DATABASE_NAME 
</property>
<property name="hibernate.default_schema">theSchemaNameUsuallydbo</property>
<property name="hibernate.connection.username">
   YourUsername
</property>
<property name="hibernate.connection.password">
   YourPasswordForMSSQL
</property>

How to create a file on Android Internal Storage?

You should use ContextWrapper like this:

ContextWrapper cw = new ContextWrapper(context);
File directory = cw.getDir("media", Context.MODE_PRIVATE);

As always, refer to documentation, ContextWrapper has a lot to offer.

How to add colored border on cardview?

As the accepted answer requires you to add a Frame Layout, here how you can do it with material design.

Add this if you haven't already

implementation 'com.google.android.material:material:1.0.0'

Now change to Cardview to MaterialCardView

<com.google.android.material.card.MaterialCardView
android:layout_width="match_parent"
android:layout_height="wrap_content"
android:layout_marginTop="16dp"
app:cardCornerRadius="8dp"
app:cardElevation="2dp"

app:strokeWidth="1dp"
app:strokeColor="@color/black">

Now you need to change the activity theme to Theme.Material. If you are using Theme.Appcompact I will suggest you to move to Theme.Material for future projects for having better material design in you app.

    <style name="AppTheme" parent="Theme.MaterialComponents.DayNight">

Changing image size in Markdown

Resizing Markdown Image Attachments in Jupyter Notebook

I'm using jupyter_core-4.4.0 & jupyter notebook.

If you're attaching your images by inserting them into the markdown like this:

![Screen%20Shot%202019-08-06%20at%201.48.10%20PM.png](attachment:Screen%20Shot%202019-08-06%20at%201.48.10%20PM.png)

These attachment links don't work:

<img src="attachment:Screen%20Shot%202019-08-06%20at%201.48.10%20PM.png" width="500"/>

DO THIS. This does work.

Just add div brackets.

<div>
<img src="attachment:Screen%20Shot%202019-08-06%20at%201.48.10%20PM.png" width="500"/>
</div>

Hope this helps!

When should a class be Comparable and/or Comparator?

Implementing Comparable means "I can compare myself with another object." This is typically useful when there's a single natural default comparison.

Implementing Comparator means "I can compare two other objects." This is typically useful when there are multiple ways of comparing two instances of a type - e.g. you could compare people by age, name etc.

Buiding Hadoop with Eclipse / Maven - Missing artifact jdk.tools:jdk.tools:jar:1.6

I use below in my MR project.

<exclusions>
                <exclusion>
                    <artifactId>jdk.tools</artifactId>
                    <groupId>jdk.tools</groupId>
                </exclusion>
</exclusions>

New self vs. new static

In addition to others' answers :

static:: will be computed using runtime information.

That means you can't use static:: in a class property because properties values :

Must be able to be evaluated at compile time and must not depend on run-time information.

class Foo {
    public $name = static::class;

}

$Foo = new Foo;
echo $Foo->name; // Fatal error

Using self::

class Foo {
    public $name = self::class;

}
$Foo = new Foo;
echo $Foo->name; // Foo

Please note that the Fatal error comment in the code i made doesn't indicate where the error happened, the error happened earlier before the object was instantiated as @Grapestain mentioned in the comments

Pass form data to another page with php

The best way to accomplish that is to use POST which is a method of Hypertext Transfer Protocol https://developer.mozilla.org/en-US/docs/Web/HTTP/Methods

index.php

<html>
<body>

<form action="site2.php" method="post">
Name: <input type="text" name="name">
Email: <input type="text" name="email">
<input type="submit">
</form>

</body>
</html> 

site2.php

 <html>
 <body>

 Hello <?php echo $_POST["name"]; ?>!<br>
 Your mail is <?php echo $_POST["mail"]; ?>.

 </body>
 </html> 

output

Hello "name" !

Your email is "[email protected]" .

Can two or more people edit an Excel document at the same time?

Yes you can. I've used it with Word and PowerPoint. You will need Office 2010 client apps and SharePoint 2010 foundation at least. You must also allow editing without checking out on the document library.

It's quite cool, you can mark regions as 'locked' so no-one can change them and you can see what other people have changed every time you save your changes to the server. You also get to see who's working on the document from the Office app. The merging happens on SharePoint 2010.

How to write inline if statement for print?

You're simply overcomplicating.

if b:
   print a

How to count the number of occurrences of a character in an Oracle varchar value?

REGEXP_COUNT should do the trick:

select REGEXP_COUNT('123-345-566', '-') from dual;

"Access is denied" JavaScript error when trying to access the document object of a programmatically-created <iframe> (IE-only)

It seems that the problem with IE comes when you try and access the iframe via the document.frames object - if you store a reference to the created iframe in a variable then you can access the injected iframe via the variable (my_iframe in the code below).

I've gotten this to work in IE6/7/8

var my_iframe;
var iframeId = "my_iframe_name"
if (navigator.userAgent.indexOf('MSIE') !== -1) {
  // IE wants the name attribute of the iframe set
  my_iframe = document.createElement('<iframe name="' + iframeId + '">');
} else {
  my_iframe = document.createElement('iframe');
}

iframe.setAttribute("src", "javascript:void(0);");
iframe.setAttribute("scrolling", "no");
iframe.setAttribute("frameBorder", "0");
iframe.setAttribute("name", iframeId);

var is = iframe.style;
is.border = is.width = is.height = "0px";

if (document.body) {
  document.body.appendChild(my_iframe);
} else {
  document.appendChild(my_iframe);
}

Determine function name from within that function (without using traceback)

Here's a future-proof approach.

Combining @CamHart's and @Yuval's suggestions with @RoshOxymoron's accepted answer has the benefit of avoiding:

  • _hidden and potentially deprecated methods
  • indexing into the stack (which could be reordered in future pythons)

So I think this plays nice with future python versions (tested on 2.7.3 and 3.3.2):

from __future__ import print_function
import inspect

def bar():
    print("my name is '{}'".format(inspect.currentframe().f_code.co_name))

Get public/external IP address?

Best answer I found

To get the remote ip address the quickest way possible. You must have to use a downloader, or create a server on your computer.

The downsides to using this simple code: (which is recommended) is that it will take 3-5 seconds to get your Remote IP Address because the WebClient when initialized always takes 3-5 seconds to check for your proxy settings.

 public static string GetIP()
 {
            string externalIP = "";
            externalIP = new WebClient().DownloadString("http://checkip.dyndns.org/");
            externalIP = (new Regex(@"\d{1,3}\.\d{1,3}\.\d{1,3}\.\d{1,3}"))
                                           .Matches(externalIP)[0].ToString();
            return externalIP;
 }

Here is how I fixed it.. (first time still takes 3-5 seconds) but after that it will always get your Remote IP Address in 0-2 seconds depending on your connection.

public static WebClient webclient = new WebClient();
public static string GetIP()
{
    string externalIP = "";
    externalIP = webclient.DownloadString("http://checkip.dyndns.org/");
    externalIP = (new Regex(@"\d{1,3}\.\d{1,3}\.\d{1,3}\.\d{1,3}"))
                                   .Matches(externalIP)[0].ToString();
    return externalIP;
}

Open web in new tab Selenium + Python

tabs = {}

def new_tab():
    global browser
    hpos = browser.window_handles.index(browser.current_window_handle)
    browser.execute_script("window.open('');")
    browser.switch_to.window(browser.window_handles[hpos + 1])
    return(browser.current_window_handle)
    
def switch_tab(name):
    global tabs
    global browser
    if not name in tabs.keys():
        tabs[name] = {'window_handle': new_tab(), 'url': url+name}
        browser.get(tabs[name]['url'])
    else:
        browser.switch_to.window(tabs[name]['window_handle'])

Search an Oracle database for tables with specific column names?

To find all tables with a particular column:

select owner, table_name from all_tab_columns where column_name = 'ID';

To find tables that have any or all of the 4 columns:

select owner, table_name, column_name
from all_tab_columns
where column_name in ('ID', 'FNAME', 'LNAME', 'ADDRESS');

To find tables that have all 4 columns (with none missing):

select owner, table_name
from all_tab_columns
where column_name in ('ID', 'FNAME', 'LNAME', 'ADDRESS')
group by owner, table_name
having count(*) = 4;

How to split a comma-separated string?

A small improvement: above solutions will not remove leading or trailing spaces in the actual String. It's better to call trim before calling split. Instead of this,

 String[] animalsArray = animals.split("\\s*,\\s*");

use

 String[] animalsArray = animals.trim().split("\\s*,\\s*");

Draw a line in a div

Answered this just to emphasize @rblarsen comment on question :

You don't need the style tags in the CSS-file

If you remove the style tag from your css file it will work.

HTML text-overflow ellipsis detection

Adding to italo's answer, you can also do this using jQuery.

function isEllipsisActive($jQueryObject) {
    return ($jQueryObject.width() < $jQueryObject[0].scrollWidth);
}

Also, as Smoky pointed out, you may want to use jQuery outerWidth() instead of width().

function isEllipsisActive($jQueryObject) {
    return ($jQueryObject.outerWidth() < $jQueryObject[0].scrollWidth);
}

Convert and format a Date in JSP

In JSP, you'd normally like to use JSTL <fmt:formatDate> for this. You can of course also throw in a scriptlet with SimpleDateFormat, but scriptlets are strongly discouraged since 2003.

Assuming that ${bean.date} returns java.util.Date, here's how you can use it:

<%@ taglib prefix="fmt" uri="http://java.sun.com/jsp/jstl/fmt" %>
...
<fmt:formatDate value="${bean.date}" pattern="yyyy-MM-dd HH:mm:ss" />

If you're actually using a java.util.Calendar, then you can invoke its getTime() method to get a java.util.Date out of it that <fmt:formatDate> accepts:

<fmt:formatDate value="${bean.calendar.time}" pattern="yyyy-MM-dd HH:mm:ss" />

Or, if you're actually holding the date in a java.lang.String (this indicates a serious design mistake in the model; you should really fix your model to store dates as java.util.Date instead of as java.lang.String!), here's how you can convert from one date string format e.g. MM/dd/yyyy to another date string format e.g. yyyy-MM-dd with help of JSTL <fmt:parseDate>.

<fmt:parseDate pattern="MM/dd/yyyy" value="${bean.dateString}" var="parsedDate" />
<fmt:formatDate value="${parsedDate}" pattern="yyyy-MM-dd" />

Databound drop down list - initial value

Add an item and set its "Selected" property to true, you will probably want to set "appenddatabounditems" property to true also so your initial value isn't deleted when databound.

If you are talking about setting an initial value that is in your databound items then hook into your ondatabound event and set which index you want to selected=true you will want to wrap it in "if not page.isPostBack then ...." though

Protected Sub DepartmentDropDownList_DataBound(ByVal sender As Object, ByVal e As    System.EventArgs) Handles DepartmentDropDownList.DataBound
    If Not Page.IsPostBack Then
        DepartmentDropDownList.SelectedValue = "somevalue"
    End If
End Sub

How to change symbol for decimal point in double.ToString()?

If you have an Asp.Net web application, you can also set it in the web.config so that it is the same throughout the whole web application

<system.web>
    ...
    <globalization 
        requestEncoding="utf-8" 
        responseEncoding="utf-8" 
        culture="en-GB" 
        uiCulture="en-GB" 
        enableClientBasedCulture="false"/>
    ...
</system.web>

LINQ Where with AND OR condition

Linq With Or Condition by using Lambda expression you can do as below

DataTable dtEmp = new DataTable();

dtEmp.Columns.Add("EmpID", typeof(int));
dtEmp.Columns.Add("EmpName", typeof(string));
dtEmp.Columns.Add("Sal", typeof(decimal));
dtEmp.Columns.Add("JoinDate", typeof(DateTime));
dtEmp.Columns.Add("DeptNo", typeof(int));

dtEmp.Rows.Add(1, "Rihan", 10000, new DateTime(2001, 2, 1), 10);
dtEmp.Rows.Add(2, "Shafi", 20000, new DateTime(2000, 3, 1), 10);
dtEmp.Rows.Add(3, "Ajaml", 25000, new DateTime(2010, 6, 1), 10);
dtEmp.Rows.Add(4, "Rasool", 45000, new DateTime(2003, 8, 1), 20);
dtEmp.Rows.Add(5, "Masthan", 22000, new DateTime(2001, 3, 1), 20);


var res2 = dtEmp.AsEnumerable().Where(emp => emp.Field<int>("EmpID")
            == 1 || emp.Field<int>("EmpID") == 2);

foreach (DataRow row in res2)
{
    Label2.Text += "Emplyee ID: " + row[0] + "   &   Emplyee Name: " + row[1] + ",  ";
}

How can I get a precise time, for example in milliseconds in Objective-C?

You can get current time in milliseconds since January 1st, 1970 using an NSDate:

- (double)currentTimeInMilliseconds {
    NSDate *date = [NSDate date];
    return [date timeIntervalSince1970]*1000;
}

Call a Class From another class

First create an object of class2 in class1 and then use that object to call any function of class2 for example write this in class1

class2 obj= new class2();
obj.thefunctioname(args);

How to use the PI constant in C++

I generally prefer defining my own: const double PI = 2*acos(0.0); because not all implementations provide it for you.

The question of whether this function gets called at runtime or is static'ed out at compile time is usually not an issue, because it only happens once anyway.

Converting cv::Mat to IplImage*

Here is the recent fix for dlib users link

cv::Mat img = ...
IplImage iplImage = cvIplImage(img);

./configure : /bin/sh^M : bad interpreter

Your configure file contains CRLF line endings (windows style) instead of simple LF line endings (unix style). Did you transfer it using FTP mode ASCII from Windows?

You can use

dos2unix configure

to fix this, or open it in vi and use :%s/^M//g; to substitute them all (use CTRL+V, CTRL+M to get the ^M)

Apache: Restrict access to specific source IP inside virtual host

In Apache 2.4, the authorization configuration syntax has changed, and the Order, Deny or Allow directives should no longer be used.

The new way to do this would be:

<VirtualHost *:8080>
    <Location />
        Require ip 192.168.1.0
    </Location>
    ...
</VirtualHost>

Further examples using the new syntax can be found in the Apache documentation: Upgrading to 2.4 from 2.2

Reading an image file into bitmap from sdcard, why am I getting a NullPointerException?

Try this code:

Bitmap bitmap = null;
File f = new File(_path);
BitmapFactory.Options options = new BitmapFactory.Options();
options.inPreferredConfig = Bitmap.Config.ARGB_8888;
try {
    bitmap = BitmapFactory.decodeStream(new FileInputStream(f), null, options);
} catch (FileNotFoundException e) {
    e.printStackTrace();
}         
image.setImageBitmap(bitmap);

Multiplication on command line terminal

If you like python and have an option to install a package, you can use this utility that I made.

# install pythonp
python -m pip install pythonp

pythonp "5*5"
25

pythonp "1 / (1+math.exp(0.5))"
0.3775406687981454

# define a custom function and pass it to another higher-order function
pythonp "n=10;functools.reduce(lambda x,y:x*y, range(1,n+1))"     
3628800

Get timezone from users browser using moment(timezone).js

Using Moment library, see their website -> https://momentjs.com/timezone/docs/#/using-timezones/converting-to-zone/

i notice they also user their own library in their website, so you can have a try using the browser console before installing it

moment().tz(String);

The moment#tz mutator will change the time zone and update the offset.

moment("2013-11-18").tz("America/Toronto").format('Z'); // -05:00
moment("2013-11-18").tz("Europe/Berlin").format('Z');   // +01:00

This information is used consistently in other operations, like calculating the start of the day.

var m = moment.tz("2013-11-18 11:55", "America/Toronto");
m.format();                     // 2013-11-18T11:55:00-05:00
m.startOf("day").format();      // 2013-11-18T00:00:00-05:00
m.tz("Europe/Berlin").format(); // 2013-11-18T06:00:00+01:00
m.startOf("day").format();      // 2013-11-18T00:00:00+01:00

Without an argument, moment#tz returns:

    the time zone name assigned to the moment instance or
    undefined if a time zone has not been set.

var m = moment.tz("2013-11-18 11:55", "America/Toronto");
m.tz();  // America/Toronto
var m = moment.tz("2013-11-18 11:55");
m.tz() === undefined;  // true

How to remove a key from Hash and get the remaining hash in Ruby/Rails?

If you want to use pure Ruby (no Rails), don't want to create extension methods (maybe you need this only in one or two places and don't want to pollute namespace with tons of methods) and don't want to edit hash in place (i.e., you're fan of functional programming like me), you can 'select':

>> x = {:a => 1, :b => 2, :c => 3}
=> {:a=>1, :b=>2, :c=>3}
>> x.select{|x| x != :a}
=> {:b=>2, :c=>3}
>> x.select{|x| ![:a, :b].include?(x)}
=> {:c=>3}
>> x
=> {:a=>1, :b=>2, :c=>3}

List all tables in postgresql information_schema

You may use also

select * from pg_tables where schemaname = 'information_schema'

In generall pg* tables allow you to see everything in the db, not constrained to your permissions (if you have access to the tables of course).

Identify if a string is a number

This will return true if input is all numbers. Don't know if it's any better than TryParse, but it will work.

Regex.IsMatch(input, @"^\d+$")

If you just want to know if it has one or more numbers mixed in with characters, leave off the ^ + and $.

Regex.IsMatch(input, @"\d")

Edit: Actually I think it is better than TryParse because a very long string could potentially overflow TryParse.

JavaScript get element by name

You want this:

function validate() {
    var acc = document.getElementsByName('acc')[0].value;
    var pass = document.getElementsByName('pass')[0].value;

    alert (acc);
}

UnicodeEncodeError: 'ascii' codec can't encode character u'\u2013' in position 3 2: ordinal not in range(128)

I had the same problem. This work fine for me:

str(objdata).encode('utf-8')

Bootstrap 3: how to make head of dropdown link clickable in navbar

This 100% works:

HTML:

<li class="dropdown">
          <a href="https://www.bkweb.co.in/" class="dropdown-toggle" >bkWeb.co.in Dropdown <span class="caret"></span></a>
          <ul class="dropdown-menu">
            <li><a href="#">Action</a></li>
            <li><a href="#">Another action</a></li>
            <li><a href="#">Something else here</a></li>
            <li role="separator" class="divider"></li>
            <li><a href="#">Separated link</a></li>
            <li role="separator" class="divider"></li>
            <li><a href="#">One more separated link</a></li>
          </ul>
        </li>

CSS:

@media (min-width:991px){
  ul.nav li.dropdown:hover ul.dropdown-menu {
    display: block;
  }
}

EXAMPLE in CODEPEN

Git: "please tell me who you are" error

Instead of doing a git pull, you can do:

git fetch
git reset --hard origin/master

Neither of those require you to configure your git user name / email.

This will destroy any uncommitted local changes / commits, and will leave your HEAD pointing to a commit (not a branch). But neither of those should be a problem for an app server since you shouldn't be making local changes or committing to that repository.

Is there a native jQuery function to switch elements?

No need to use jquery for any major browser to swap elements at the moment. Native dom method, insertAdjacentElement does the trick no matter how they are located:

var el1 = $("el1");
var el2 = $("el2");
el1[0].insertAdjacentElement("afterend", el2[0]);

List files in local git repo?

git ls-tree --full-tree -r HEAD and git ls-files return all files at once. For a large project with hundreds or thousands of files, and if you are interested in a particular file/directory, you may find more convenient to explore specific directories. You can do it by obtaining the ID/SHA-1 of the directory that you want to explore and then use git cat-file -p [ID/SHA-1 of directory]. For example:

git cat-file -p 14032aabd85b43a058cfc7025dd4fa9dd325ea97
100644 blob b93a4953fff68df523aa7656497ee339d6026d64    glyphicons-halflings-regular.eot
100644 blob 94fb5490a2ed10b2c69a4a567a4fd2e4f706d841    glyphicons-halflings-regular.svg
100644 blob 1413fc609ab6f21774de0cb7e01360095584f65b    glyphicons-halflings-regular.ttf
100644 blob 9e612858f802245ddcbf59788a0db942224bab35    glyphicons-halflings-regular.woff
100644 blob 64539b54c3751a6d9adb44c8e3a45ba5a73b77f0    glyphicons-halflings-regular.woff2

In the example above, 14032aabd85b43a058cfc7025dd4fa9dd325ea97 is the ID/SHA-1 of the directory that I wanted to explore. In this case, the result was that four files within that directory were being tracked by my Git repo. If the directory had additional files, it would mean those extra files were not being tracked. You can add files using git add <file>... of course.

How to read and write excel file

Another way to read/write Excel files is to use Windmill. It provides a fluent API to process Excel and CSV files.

Import data

try (Stream<Row> rowStream = Windmill.parse(FileSource.of(new FileInputStream("myFile.xlsx")))) {
  rowStream
    // skip the header row that contains the column names
    .skip(1)
    .forEach(row -> {
      System.out.println(
        "row n°" + row.rowIndex()
        + " column 'User login' value : " + row.cell("User login").asString()
        + " column n°3 number value : " + row.cell(2).asDouble().value() // index is zero-based
      );
    });
}

Export data

Windmill
  .export(Arrays.asList(bean1, bean2, bean3))
  .withHeaderMapping(
    new ExportHeaderMapping<Bean>()
      .add("Name", Bean::getName)
      .add("User login", bean -> bean.getUser().getLogin())
  )
  .asExcel()
  .writeTo(new FileOutputStream("Export.xlsx"));

CSS way to horizontally align table

Steven is right, in theory:

the “correct” way to center a table using CSS. Conforming browsers ought to center tables if the left and right margins are equal. The simplest way to accomplish this is to set the left and right margins to “auto.” Thus, one might write in a style sheet:

table
{ 
    margin-left: auto;
    margin-right: auto;
}

But the article mentioned in the beginning of this answer gives you all the other way to center a table.

An elegant css cross-browser solution: This works in both MSIE 6 (Quirks and Standards), Mozilla, Opera and even Netscape 4.x without setting any explicit widths:

div.centered 
{
    text-align: center;
}

div.centered table 
{
    margin: 0 auto; 
    text-align: left;
}


<div class="centered">
    <table>
    …
    </table>
</div>

Sorting a list using Lambda/Linq to objects

This can be done as

list.Sort( (emp1,emp2)=>emp1.FirstName.CompareTo(emp2.FirstName) );

The .NET framework is casting the lambda (emp1,emp2)=>int as a Comparer<Employee>.

This has the advantage of being strongly typed.

Can you 'exit' a loop in PHP?

You are looking for the break statement.

$arr = array('one', 'two', 'three', 'four', 'stop', 'five');
while (list(, $val) = each($arr)) {
    if ($val == 'stop') {
        break;    /* You could also write 'break 1;' here. */
    }
    echo "$val<br />\n";
}

How can I replace newlines using PowerShell?

A CRLF is two characters, of course, the CR and the LF. However, `n consists of both. For example:

PS C:\> $x = "Hello
>> World"

PS C:\> $x
Hello
World
PS C:\> $x.contains("`n")
True
PS C:\> $x.contains("`r")
False
PS C:\> $x.replace("o`nW","o There`nThe W")
Hello There
The World
PS C:\>

I think you're running into problems with the `r. I was able to remove the `r from your example, use only `n, and it worked. Of course, I don't know exactly how you generated the original string so I don't know what's in there.

Is there a splice method for strings?

I solved my problem using this code, is a somewhat replacement for the missing splice.

let str = "I need to remove a character from this";
let pos = str.indexOf("character")

if(pos>-1){
  let result = str.slice(0, pos-2) + str.slice(pos, str.length);
  console.log(result) //I need to remove character from this 
}

I needed to remove a character before/after a certain word, after you get the position the string is split in two and then recomposed by flexibly removing characters using an offset along pos

How to SSH into Docker?

Firstly you need to install a SSH server in the images you wish to ssh-into. You can use a base image for all your container with the ssh server installed. Then you only have to run each container mapping the ssh port (default 22) to one to the host's ports (Remote Server in your image), using -p <hostPort>:<containerPort>. i.e:

docker run -p 52022:22 container1 
docker run -p 53022:22 container2

Then, if ports 52022 and 53022 of host's are accessible from outside, you can directly ssh to the containers using the ip of the host (Remote Server) specifying the port in ssh with -p <port>. I.e.:

ssh -p 52022 myuser@RemoteServer --> SSH to container1

ssh -p 53022 myuser@RemoteServer --> SSH to container2

Convert String to Double - VB

The international versions:

    Public Shared Function GetDouble(ByVal doublestring As String) As Double
        Dim retval As Double
        Dim sep As String = CultureInfo.CurrentCulture.NumberFormat.NumberDecimalSeparator

        Double.TryParse(Replace(Replace(doublestring, ".", sep), ",", sep), retval)
        Return retval
    End Function

    ' NULLABLE VERSION:
    Public Shared Function GetDoubleNullable(ByVal doublestring As String) As Double?
        Dim retval As Double
        Dim sep As String = CultureInfo.CurrentCulture.NumberFormat.NumberDecimalSeparator

        If Double.TryParse(Replace(Replace(doublestring, ".", sep), ",", sep), retval) Then
            Return retval
        Else
            Return Nothing
        End If
    End Function

Results:

        ' HUNGARIAN REGIONAL SETTINGS (NumberDecimalSeparator: ,)

        ' Clean Double.TryParse
        ' -------------------------------------------------
        Double.TryParse("1.12", d1)     ' Type: DOUBLE     Value: d1 = 0.0
        Double.TryParse("1,12", d2)     ' Type: DOUBLE     Value: d2 = 1.12
        Double.TryParse("abcd", d3)     ' Type: DOUBLE     Value: d3 = 0.0

        ' GetDouble() method
        ' -------------------------------------------------
        d1 = GetDouble("1.12")          ' Type: DOUBLE     Value: d1 = 1.12
        d2 = GetDouble("1,12")          ' Type: DOUBLE     Value: d2 = 1.12
        d3 = GetDouble("abcd")          ' Type: DOUBLE     Value: d3 = 0.0

        ' Nullable version - GetDoubleNullable() method
        ' -------------------------------------------------
        d1n = GetDoubleNullable("1.12") ' Type: DOUBLE?    Value: d1n = 1.12
        d2n = GetDoubleNullable("1,12") ' Type: DOUBLE?    Value: d2n = 1.12
        d3n = GetDoubleNullable("abcd") ' Type: DOUBLE?    Value: d3n = Nothing

What is the difference between an interface and abstract class?

I am constructing a building of 300 floors

The building's blueprint interface

  • For example, Servlet(I)

Building constructed up to 200 floors - partially completed---abstract

  • Partial implementation, for example, generic and HTTP servlet

Building construction completed-concrete

  • Full implementation, for example, own servlet

Interface

  • We don't know anything about implementation, just requirements. We can go for an interface.
  • Every method is public and abstract by default
  • It is a 100% pure abstract class
  • If we declare public we cannot declare private and protected
  • If we declare abstract we cannot declare final, static, synchronized, strictfp and native
  • Every interface has public, static and final
  • Serialization and transient is not applicable, because we can't create an instance for in interface
  • Non-volatile because it is final
  • Every variable is static
  • When we declare a variable inside an interface we need to initialize variables while declaring
  • Instance and static block not allowed

Abstract

  • Partial implementation
  • It has an abstract method. An addition, it uses concrete
  • No restriction for abstract class method modifiers
  • No restriction for abstract class variable modifiers
  • We cannot declare other modifiers except abstract
  • No restriction to initialize variables

Taken from DurgaJobs Website

Downloading a picture via urllib and python

Just for the record, using requests library.

import requests
f = open('00000001.jpg','wb')
f.write(requests.get('http://www.gunnerkrigg.com//comics/00000001.jpg').content)
f.close()

Though it should check for requests.get() error.

1052: Column 'id' in field list is ambiguous

What you are probably really wanting to do here is use the union operator like this:

(select ID from Logo where AccountID = 1 and Rendered = 'True')
  union
  (select ID from Design where AccountID = 1 and Rendered = 'True')
  order by ID limit 0, 51

Here's the docs for it https://dev.mysql.com/doc/refman/5.0/en/union.html

syntaxerror: unexpected character after line continuation character in python

You need to quote that filename:

f = open("D\\python\\HW\\2_1 - Copy.cp", "r")

Otherwise the bare backslash after the D is interpreted as a line-continuation character, and should be followed by a newline. This is used to extend long expressions over multiple lines, for readability:

print "This is a long",\
      "line of text",\
      "that I'm printing."

Also, you shouldn't have semicolons (;) at the end of your statements in Python.

Comparing strings in Java

Using the == operator will compare the references to the strings not the string themselves.

Ok, you have to toString() the Editable. I loaded up some of the code I had before that dealt with this situation.

String passwd1Text = passw1.getText().toString();
String passwd2Text = passw2.getText().toString();

if (passwd1Text.equals(passwd2Text))
{
}

How do you recursively unzip archives in a directory and its subdirectories from the Unix command-line?

You could use find along with the -exec flag in a single command line to do the job

find . -name "*.zip" -exec unzip {} \;

How to fix java.net.SocketException: Broken pipe?

The issue could be that your deployed files are not updated with the correct RMI methods. Check to see that your RMI interface has updated parameters, or updated data structures that your client does not have. Or that your RMI client has no parameters that differ from what your server version has.

This is just an educated guess. After re-deploying my server application's class files and re-testing, the problem of "Broken pipe" went away.

Get top 1 row of each group

Here are 3 separate approaches to the problem in hand along with the best choices of indexing for each of those queries (please try out the indexes yourselves and see the logical read, elapsed time, execution plan. I have provided the suggestions from my experience on such queries without executing for this specific problem).

Approach 1: Using ROW_NUMBER(). If rowstore index is not being able to enhance the performance, you can try out nonclustered/clustered columnstore index as for queries with aggregation and grouping and for tables which are ordered by in different columns all the times, columnstore index usually is the best choice.

;WITH CTE AS
    (
       SELECT   *,
                RN = ROW_NUMBER() OVER (PARTITION BY DocumentID ORDER BY DateCreated DESC)
       FROM     DocumentStatusLogs
    )
    SELECT  ID      
        ,DocumentID 
        ,Status     
        ,DateCreated
    FROM    CTE
    WHERE   RN = 1;

Approach 2: Using FIRST_VALUE. If rowstore index is not being able to enhance the performance, you can try out nonclustered/clustered columnstore index as for queries with aggregation and grouping and for tables which are ordered by in different columns all the times, columnstore index usually is the best choice.

SELECT  DISTINCT
    ID      = FIRST_VALUE(ID) OVER (PARTITION BY DocumentID ORDER BY DateCreated DESC)
    ,DocumentID
    ,Status     = FIRST_VALUE(Status) OVER (PARTITION BY DocumentID ORDER BY DateCreated DESC)
    ,DateCreated    = FIRST_VALUE(DateCreated) OVER (PARTITION BY DocumentID ORDER BY DateCreated DESC)
FROM    DocumentStatusLogs;

Approach 3: Using CROSS APPLY. Creating rowstore index on DocumentStatusLogs table covering the columns used in the query should be enough to cover the query without need of a columnstore index.

SELECT  DISTINCT
    ID      = CA.ID
    ,DocumentID = D.DocumentID
    ,Status     = CA.Status 
    ,DateCreated    = CA.DateCreated
FROM    DocumentStatusLogs D
    CROSS APPLY (
            SELECT  TOP 1 I.*
            FROM    DocumentStatusLogs I
            WHERE   I.DocumentID = D.DocumentID
            ORDER   BY I.DateCreated DESC
            ) CA;

React Native: JAVA_HOME is not set and no 'java' command could be found in your PATH

I ran this in the command prompt(have windows 7 os): JAVA_HOME=C:\Program Files\Android\Android Studio\jre

where what its = to is the path to that jre folder, so anyone's can be different.

How can I easily convert DataReader to List<T>?

The simplest Solution :

var dt=new DataTable();
dt.Load(myDataReader);
list<DataRow> dr=dt.AsEnumerable().ToList();

Creating a List of Lists in C#

you should not use Nested List in List.

List<List<T>> 

is not legal, even if T were a defined type.

https://msdn.microsoft.com/en-us/library/ms182144.aspx

Server configuration by allow_url_fopen=0 in

THIS IS A VERY SIMPLE PROBLEM

Here is the best method for solve this problem.

Step 1 : Login to your cPanel (http://website.com/cpanel OR http://cpanel.website.com).

Step 2 : SOFTWARE -> Select PHP Version

Step 3 : Change Your Current PHP version : 5.6

Step 3 : HIT 'Set as current' [ ENJOY ]

Lambda expression to convert array/List of String to array/List of Integers

The helper methods from the accepted answer are not needed. Streams can be used with lambdas or usually shortened using Method References. Streams enable functional operations. map() converts the elements and collect(...) or toArray() wrap the stream back up into an array or collection.

Venkat Subramaniam's talk (video) explains it better than me.

1 Convert List<String> to List<Integer>

List<String> l1 = Arrays.asList("1", "2", "3");
List<Integer> r1 = l1.stream().map(Integer::parseInt).collect(Collectors.toList());

// the longer full lambda version:
List<Integer> r1 = l1.stream().map(s -> Integer.parseInt(s)).collect(Collectors.toList());

2 Convert List<String> to int[]

int[] r2 = l1.stream().mapToInt(Integer::parseInt).toArray();

3 Convert String[] to List<Integer>

String[] a1 = {"4", "5", "6"};
List<Integer> r3 = Stream.of(a1).map(Integer::parseInt).collect(Collectors.toList());

4 Convert String[] to int[]

int[] r4 = Stream.of(a1).mapToInt(Integer::parseInt).toArray();

5 Convert String[] to List<Double>

List<Double> r5 = Stream.of(a1).map(Double::parseDouble).collect(Collectors.toList());

6 (bonus) Convert int[] to String[]

int[] a2 = {7, 8, 9};
String[] r6 = Arrays.stream(a2).mapToObj(Integer::toString).toArray(String[]::new);

Lots more variations are possible of course.

Also see Ideone version of these examples. Can click fork and then run to run in the browser.

Wrapping text inside input type="text" element HTML/CSS

That is the textarea's job - for multiline text input. The input won't do it; it wasn't designed to do it.

So use a textarea. Besides their visual differences, they are accessed via JavaScript the same way (use value property).

You can prevent newlines being entered via the input event and simply using a replace(/\n/g, '').

Iteration over std::vector: unsigned vs signed index variable

The two code segments work the same. However, unsigned int" route is correct. Using unsigned int types will work better with the vector in the instance you used it. Calling the size() member function on a vector returns an unsigned integer value, so you want to be comparing the variable "i" to a value of its own type.

Also, if you are still a little uneasy about how "unsigned int" looks in your code, try "uint". This is basically a shortened version of "unsigned int" and it works exactly the same. You also don't need to include other headers to use it.

Change Bootstrap tooltip color

This worked for me .

.tooltip .arrow:before {
    border-top-color: #008ec3 !important;
}

.tooltip .tooltip-inner {
    background-color: #008ec3;
}

Compare 2 JSON objects

Simply parsing the JSON and comparing the two objects is not enough because it wouldn't be the exact same object references (but might be the same values).

You need to do a deep equals.

From http://threebit.net/mail-archive/rails-spinoffs/msg06156.html - which seems the use jQuery.

Object.extend(Object, {
   deepEquals: function(o1, o2) {
     var k1 = Object.keys(o1).sort();
     var k2 = Object.keys(o2).sort();
     if (k1.length != k2.length) return false;
     return k1.zip(k2, function(keyPair) {
       if(typeof o1[keyPair[0]] == typeof o2[keyPair[1]] == "object"){
         return deepEquals(o1[keyPair[0]], o2[keyPair[1]])
       } else {
         return o1[keyPair[0]] == o2[keyPair[1]];
       }
     }).all();
   }
});

Usage:

var anObj = JSON.parse(jsonString1);
var anotherObj= JSON.parse(jsonString2);

if (Object.deepEquals(anObj, anotherObj))
   ...

What's the difference between struct and class in .NET?

Well, for starters, a struct is passed by value rather than by reference. Structs are good for relatively simple data structures, while classes have a lot more flexibility from an architectural point of view via polymorphism and inheritance.

Others can probably give you more detail than I, but I use structs when the structure that I am going for is simple.

Cannot GET / Nodejs Error

Much like leonardocsouza, I had the same problem. To clarify a bit, this is what my folder structure looked like when I ran node server.js

node_modules/
app/
  index.html
  server.js

After printing out the __dirname path, I realized that the __dirname path was where my server was running (app/).

So, the answer to your question is this:

If your server.js file is in the same folder as the files you are trying to render, then

app.use( express.static( path.join( application_root, 'site') ) );

should actually be

app.use(express.static(application_root));

The only time you would want to use the original syntax that you had would be if you had a folder tree like so:

app/
  index.html
node_modules
server.js

where index.html is in the app/ directory, whereas server.js is in the root directory (i.e. the same level as the app/ directory).

Side note: Intead of calling the path utility, you can use the syntax application_root + 'site' to join a path.

Overall, your code could look like:

// Module dependencies.
var application_root = __dirname,
express = require( 'express' ), //Web framework
mongoose = require( 'mongoose' ); //MongoDB integration

//Create server
var app = express();

// Configure server
app.configure( function() {

    //Don't change anything here...

    //Where to serve static content
    app.use( express.static( application_root ) );

    //Nothing changes here either...
});

//Start server --- No changes made here
var port = 5000;
app.listen( port, function() {
    console.log( 'Express server listening on port %d in %s mode', port, app.settings.env );
});

Windows batch: call more than one command in a FOR loop?

Using & is fine for short commands, but that single line can get very long very quick. When that happens, switch to multi-line syntax.

FOR /r %%X IN (*.txt) DO (
    ECHO %%X
    DEL %%X
)

Placement of ( and ) matters. The round brackets after DO must be placed on the same line, otherwise the batch file will be incorrect.

See if /?|find /V "" for details.

Adding a Time to a DateTime in C#

You can use the DateTime.Add() method to add the time to the date.

DateTime date = DateTime.Now;
TimeSpan time = new TimeSpan(36, 0, 0, 0);
DateTime combined = date.Add(time);
Console.WriteLine("{0:dddd}", combined);

You can also create your timespan by parsing a String, if that is what you need to do.

Alternatively, you could look at using other controls. You didn't mention if you are using winforms, wpf or asp.net, but there are various date and time picker controls that support selection of both date and time.

What is causing "Unable to allocate memory for pool" in PHP?

As Bokan has mentioned, you can up the memory if available, and he is right on how counter productive setting TTL to 0 is.

NotE: This is how I fixed this error for my particular problem. Its a generic issue that can be caused by allot of things so only follow the below if you get the error and you think its caused by duplicate PHP files being loaded into APC.

The issue I was having was when I released a new version of my PHP application. Ie replaced all my .php files with new ones APC would load both versions into cache.

Because I didnt have enough memory for two versions of the php files APC would run out of memory.

There is a option called apc.stat to tell APC to check if a particular file has changed and if so replace it, this is typically ok for development because you are constantly making changes however on production its usually turned off as it was with in my case - http://www.php.net/manual/en/apc.configuration.php#ini.apc.stat

Turning apc.stat on would fix this issue if you are ok with the performance hit.

The solution I came up with for my problem is check if the the project version has changed and if so empty the cache and reload the page.

define('PROJECT_VERSION', '0.28'); 

if(apc_exists('MY_APP_VERSION') ){

    if(apc_fetch('MY_APP_VERSION') != PROJECT_VERSION){
        apc_clear_cache();
        apc_store ('MY_APP_VERSION', PROJECT_VERSION);
        header('Location: ' . 'http'.(empty($_SERVER['HTTPS'])?'':'s').'://'.$_SERVER['SERVER_NAME'].$_SERVER['REQUEST_URI']);
        exit;  
    }

}else{
    apc_store ('MY_APP_VERSION', PROJECT_VERSION);
}

Java how to sort a Linked List?

Here is the example to sort implemented linked list in java without using any standard java libraries.

package SelFrDemo;

class NodeeSort {
    Object value;
    NodeeSort next;

    NodeeSort(Object val) {
        value = val;
        next = null;

    }

    public Object getValue() {
        return value;
    }

    public void setValue(Object value) {
        this.value = value;
    }

    public NodeeSort getNext() {
        return next;
    }

    public void setNext(NodeeSort next) {
        this.next = next;
    }

}

public class SortLinkList {
    NodeeSort head;
    int size = 0;

    NodeeSort add(Object val) {
        // TODO Auto-generated method stub
        if (head == null) {
            NodeeSort nodee = new NodeeSort(val);
            head = nodee;
            size++;
            return head;
        }
        NodeeSort temp = head;

        while (temp.next != null) {
            temp = temp.next;
        }

        NodeeSort newNode = new NodeeSort(val);
        temp.setNext(newNode);
        newNode.setNext(null);
        size++;
        return head;
    }

    NodeeSort sort(NodeeSort nodeSort) {

        for (int i = size - 1; i >= 1; i--) {
            NodeeSort finalval = nodeSort;
            NodeeSort tempNode = nodeSort;

            for (int j = 0; j < i; j++) {

                int val1 = (int) nodeSort.value;
                NodeeSort nextnode = nodeSort.next;
                int val2 = (int) nextnode.value;
                if (val1 > val2) {

                    if (nodeSort.next.next != null) {
                        NodeeSort CurrentNext = nodeSort.next.next;
                        nextnode.next = nodeSort;
                        nextnode.next.next = CurrentNext;
                        if (j == 0) {
                            finalval = nextnode;
                        } else
                            nodeSort = nextnode;

                        for (int l = 1; l < j; l++) {
                            tempNode = tempNode.next;
                        }

                        if (j != 0) {
                            tempNode.next = nextnode;

                            nodeSort = tempNode;
                        }
                    } else if (nodeSort.next.next == null) {
                        nextnode.next = nodeSort;
                        nextnode.next.next = null;
                        for (int l = 1; l < j; l++) {
                            tempNode = tempNode.next;
                        }
                        tempNode.next = nextnode;
                        nextnode = tempNode;
                        nodeSort = tempNode;

                    }

                } else
                    nodeSort = tempNode;
                nodeSort = finalval;
                tempNode = nodeSort;
                for (int k = 0; k <= j && j < i - 1; k++) {
                    nodeSort = nodeSort.next;
                }

            }

        }
        return nodeSort;

    }

    public static void main(String[] args) {
        SortLinkList objsort = new SortLinkList();
        NodeeSort nl1 = objsort.add(9);
        NodeeSort nl2 = objsort.add(71);
        NodeeSort nl3 = objsort.add(6);
        NodeeSort nl4 = objsort.add(81);
        NodeeSort nl5 = objsort.add(2);

        NodeeSort NodeSort = nl5;

        NodeeSort finalsort = objsort.sort(NodeSort);
        while (finalsort != null) {
            System.out.println(finalsort.getValue());
            finalsort = finalsort.getNext();
        }

    }
}

How to correctly use Html.ActionLink with ASP.NET MVC 4 Areas

Below are some of the way by which you can create a link button in MVC.

@Html.ActionLink("Admin", "Index", "Home", new { area = "Admin" }, null)  
@Html.RouteLink("Admin", new { action = "Index", controller = "Home", area = "Admin" })  
@Html.Action("Action", "Controller", new { area = "AreaName" })  
@Url.Action("Action", "Controller", new { area = "AreaName" })  
<a class="ui-btn" data-val="abc" href="/Home/Edit/ANTON">Edit</a>  
<a data-ajax="true" data-ajax-method="GET" data-ajax-mode="replace" data-ajax-update="#CustomerList" href="/Home/Germany">Customer from Germany</a>  
<a data-ajax="true" data-ajax-method="GET" data-ajax-mode="replace" data-ajax-update="#CustomerList" href="/Home/Mexico">Customer from Mexico</a> 

Hope this will help you.

How to install psycopg2 with "pip" on Python?

Note: Since a while back, there are binary wheels for Windows in PyPI, so this should no longer be an issue for Windows users. Below are solutions for Linux, Mac users, since lots of them find this post through web searches.


Option 1

Install the psycopg2-binary PyPI package instead, it has Python wheels for Linux and Mac OS.

pip install psycopg2-binary

Option 2

Install the prerequsisites for building the psycopg2 package from source:

Debian/Ubuntu

Python 3

sudo apt install libpq-dev python3-dev

You might need to install python3.8-dev or similar for e.g. Python 3.8.

Python 21

sudo apt install libpq-dev python-dev

If that's not enough, try

sudo apt install build-essential

or

sudo apt install postgresql-server-dev-all

as well before installing psycopg2 again.

CentOS 6

See Banjer's answer


1 Really? It's 2020

Get loop count inside a Python FOR loop

Agree with Nick. Here is more elaborated code.

#count=0
for idx, item in enumerate(list):
    print item
    #count +=1
    #if count % 10 == 0:
    if (idx+1) % 10 == 0:
        print 'did ten'

I have commented out the count variable in your code.

twig: IF with multiple conditions

If I recall correctly Twig doesn't support || and && operators, but requires or and and to be used respectively. I'd also use parentheses to denote the two statements more clearly although this isn't technically a requirement.

{%if ( fields | length > 0 ) or ( trans_fields | length > 0 ) %}

Expressions

Expressions can be used in {% blocks %} and ${ expressions }.

Operator    Description
==          Does the left expression equal the right expression?
+           Convert both arguments into a number and add them.
-           Convert both arguments into a number and substract them.
*           Convert both arguments into a number and multiply them.
/           Convert both arguments into a number and divide them.
%           Convert both arguments into a number and calculate the rest of the integer division.
~           Convert both arguments into a string and concatenate them.
or          True if the left or the right expression is true.
and         True if the left and the right expression is true.
not         Negate the expression.

For more complex operations, it may be best to wrap individual expressions in parentheses to avoid confusion:

{% if (foo and bar) or (fizz and (foo + bar == 3)) %}

How do I output text without a newline in PowerShell?

The answer by shufler is correct. Stated another way: Instead of passing the values to Write-Output using the ARRAY FORM,

Write-Output "Parameters are:" $Year $Month $Day

or the equivalent by multiple calls to Write-Output,

Write-Output "Parameters are:"
Write-Output $Year
Write-Output $Month
Write-Output $Day
Write-Output "Done."

concatenate your components into a STRING VARIABLE first:

$msg="Parameters are: $Year $Month $Day"
Write-Output $msg

This will prevent the intermediate CRLFs caused by calling Write-Output multiple times (or ARRAY FORM), but of course will not suppress the final CRLF of the Write-Output commandlet. For that, you will have to write your own commandlet, use one of the other convoluted workarounds listed here, or wait until Microsoft decides to support the -NoNewline option for Write-Output.

Your desire to provide a textual progress meter to the console (i.e. "....") as opposed to writing to a log file, should also be satisfied by using Write-Host. You can accomplish both by collecting the msg text into a variable for writing to the log AND using Write-Host to provide progress to the console. This functionality can be combined into your own commandlet for greatest code reuse.

Adding local .aar files to Gradle build using "flatDirs" is not working

This solution is working with Android Studio 4.0.1.

Apart from creating a new module as suggested in above solution, you can try this solution.

If you have multiple modules in your application and want to add aar to just one of the module then this solution come handy.

In your root project build.gradle

add

repositories {
flatDir {
    dirs 'libs'
}}

Then in the module where you want to add the .aar file locally. simply add below lines of code.

dependencies {
api fileTree(include: ['*.aar'], dir: 'libs')
implementation files('libs/<yourAarName>.aar')

}

Happy Coding :)

Get the name of an object's type

You should use somevar.constructor.name like a:

_x000D_
_x000D_
    _x000D_
    const getVariableType = a => a.constructor.name.toLowerCase();_x000D_
_x000D_
    const d = new Date();_x000D_
    const res1 = getVariableType(d); // 'date'_x000D_
    const num = 5;_x000D_
    const res2 = getVariableType(num); // 'number'_x000D_
    const fn = () => {};_x000D_
    const res3 = getVariableType(fn); // 'function'_x000D_
_x000D_
    console.log(res1); // 'date'_x000D_
    console.log(res2); // 'number'_x000D_
    console.log(res3); // 'function'
_x000D_
_x000D_
_x000D_

How to use regex in file find

find /home/test -regextype posix-extended -regex '^.*test\.log\.[0-9]{4}-[0-9]{2}-[0-9]{2}\.zip' -mtime +3
  1. -name uses globular expressions, aka wildcards. What you want is -regex
  2. To use intervals as you intend, you need to tell find to use Extended Regular Expressions via the -regextype posix-extended flag
  3. You need to escape out the periods because in regex a period has the special meaning of any single character. What you want is a literal period denoted by \.
  4. To match only those files that are greater than 3 days old, you need to prefix your number with a + as in -mtime +3.

Proof of Concept

$ find . -regextype posix-extended -regex '^.*test\.log\.[0-9]{4}-[0-9]{2}-[0-9]{2}\.zip'
./test.log.1234-12-12.zip

Android notification is not showing

This tripped me up today, but I realized it was because on Android 9.0 (Pie), Do Not Disturb by default also hides all notifications, rather than just silencing them like in Android 8.1 (Oreo) and before. This doesn't apply to notifications.

I like having DND on for my development device, so going into the DND settings and changing the setting to simply silence the notifications (but not hide them) fixed it for me.

What is the difference between DSA and RSA?

With reference to man ssh-keygen, the length of a DSA key is restricted to exactly 1024 bit to remain compliant with NIST's FIPS 186-2. Nonetheless, longer DSA keys are theoretically possible; FIPS 186-3 explicitly allows them. Furthermore, security is no longer guaranteed with 1024 bit long RSA or DSA keys.

In conclusion, a 2048 bit RSA key is currently the best choice.

MORE PRECAUTIONS TO TAKE

Establishing a secure SSH connection entails more than selecting safe encryption key pair technology. In view of Edward Snowden's NSA revelations, one has to be even more vigilant than what previously was deemed sufficient.

To name just one example, using a safe key exchange algorithm is equally important. Here is a nice overview of current best SSH hardening practices.

How to list the files inside a JAR file?

The most robust mechanism for listing all resources in the classpath is currently to use this pattern with ClassGraph, because it handles the widest possible array of classpath specification mechanisms, including the new JPMS module system. (I am the author of ClassGraph.)

How to know the name of the JAR file where my main class lives?

URI mainClasspathElementURI;
try (ScanResult scanResult = new ClassGraph().whitelistPackages("x.y.z")
        .enableClassInfo().scan()) {
    mainClasspathElementURI =
            scanResult.getClassInfo("x.y.z.MainClass").getClasspathElementURI();
}

How can I read the contents of a directory in a similar fashion within a JAR file?

List<String> classpathElementResourcePaths;
try (ScanResult scanResult = new ClassGraph().overrideClasspath(mainClasspathElementURI)
        .scan()) {
    classpathElementResourcePaths = scanResult.getAllResources().getPaths();
}

There are lots of other ways to deal with resources too.

Cannot get OpenCV to compile because of undefined references?

This is a linker issue. Try:

g++ -o test_1 test_1.cpp `pkg-config opencv --cflags --libs`

This should work to compile the source. However, if you recently compiled OpenCV from source, you will meet linking issue in run-time, the library will not be found. In most cases, after compiling libraries from source, you need to do finally:

sudo ldconfig

Get RETURN value from stored procedure in SQL

Assign after the EXEC token:

DECLARE @returnValue INT

EXEC @returnValue = SP_One

php $_POST array empty upon form submission

I could solve the problem using enctype="application/x-www-form-urlencoded" as the default is "text/plain". When you check in $DATA the seperator is a space for "text/plain" and a special character for the "urlencoded".

Kind regards Frank

Ruby max integer

as @Jörg W Mittag pointed out: in jruby, fix num size is always 8 bytes long. This code snippet shows the truth:

fmax = ->{
  if RUBY_PLATFORM == 'java'
    2**63 - 1
  else
    2**(0.size * 8 - 2) - 1
  end
}.call

p fmax.class     # Fixnum

fmax = fmax + 1  

p fmax.class     #Bignum

when I try to open an HTML file through `http://localhost/xampp/htdocs/index.html` it says unable to connect to localhost

All created by user files saved in C:\xampp\htdocs directory by default, so no need to type the default path in a browser window, just type http://localhost/yourfilename.php or http://localhost/yourfoldername/yourfilename.php this will show you the content of your new page.

mysql is not recognised as an internal or external command,operable program or batch

MYSQL_HOME variable value:C:\Program Files\MySQL\MySQL Server 5.0\bin %MYSQL_HOME%\bin

See the problem? This resolves to a path of C:\Program Files\MySQL\MySQL Server 5.0\bin\bin

Error: Configuration with name 'default' not found in Android Studio

If suppose you spotted this error after removing certain node modules, ideally should not be present the library under build.gradle(Module:app) . It can be removed manually and sync the project again.

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

Nicest solution that I was able to figure out was with bluebird promises. You can just do Promise.resolve(files).each(fs.readFileAsync); which guarantees that promises are resolved sequentially in order.

How can I match a string with a regex in Bash?

shopt -s nocasematch

if [[ sed-4.2.2.$LINE =~ (yes|y)$ ]]
 then exit 0 
fi

Ignore fields from Java object dynamically while sending as JSON from Spring MVC

Would not creating a UserJsonResponse class and populating with the wanted fields be a cleaner solution?

Returning directly a JSON seems a great solution when you want to give all the model back. Otherwise it just gets messy.

In the future, for example you might want to have a JSON field that does not match any Model field and then you're in a bigger trouble.

How to iterate a table rows with JQuery and access some cell values?

try this

var value = iterate('tr.item span.value');
var quantity = iterate('tr.item span.quantity');

function iterate(selector)
{
  var result = '';
  if ($(selector))
  {
    $(selector).each(function ()
    {
      if (result == '')
      {
        result = $(this).html();
      }
      else
      {
        result = result + "," + $(this).html();
      }
    });
  }
}

XPath to select multiple tags

You can avoid the repetition with an attribute test instead:

a/b/*[local-name()='c' or local-name()='d' or local-name()='e']

Contrary to Dimitre's antagonistic opinion, the above is not incorrect in a vacuum where the OP has not specified the interaction with namespaces. The self:: axis is namespace restrictive, local-name() is not. If the OP's intention is to capture c|d|e regardless of namespace (which I'd suggest is even a likely scenario given the OR nature of the problem) then it is "another answer that still has some positive votes" which is incorrect.

You can't be definitive without definition, though I'm quite happy to delete my answer as genuinely incorrect if the OP clarifies his question such that I am incorrect.

Make a VStack fill the width of the screen in SwiftUI

An alternative stacking arrangement which works and is perhaps a bit more intuitive is the following:

struct ContentView: View {
    var body: some View {
        HStack() {
            VStack(alignment: .leading) {
                Text("Hello World")
                    .font(.title)
                Text("Another")
                    .font(.body)
                Spacer()
            }
            Spacer()
        }.background(Color.red)
    }
}

The content can also easily be re-positioned by removing the Spacer()'s if necessary.

adding/removing Spacers to change position

Console errors. Failed to load resource: net::ERR_INSECURE_RESPONSE

I had this problem with chrome when I was working on a WordPress site. I added this code

$_SERVER['HTTPS'] = false;

into the theme's functions.php file - it asks you to log in again when you save the file but once it's logged in it works straight away.

Disable the postback on an <ASP:LinkButton>

Why not use an empty ajax update panel and wire the linkbutton's click event to it? This way only the update panel will get updated, thus avoiding a postback and allowing you to run your javascript

Android "elevation" not showing a shadow

If you have a view with no background this line will help you

android:outlineProvider="bounds"

By default shadow is determined by view's background, so if there is no background, there will be no shadow also.

Intro to GPU programming

I think the others have answered your second question. As for the first, the "Hello World" of CUDA, I don't think there is a set standard, but personally, I'd recommend a parallel adder (i.e. a programme that sums N integers).

If you look the "reduction" example in the NVIDIA SDK, the superficially simple task can be extended to demonstrate numerous CUDA considerations such as coalesced reads, memory bank conflicts and loop unrolling.

See this presentation for more info:

http://www.gpgpu.org/sc2007/SC07_CUDA_5_Optimization_Harris.pdf

What does -XX:MaxPermSize do?

The permanent space is where the classes, methods, internalized strings, and similar objects used by the VM are stored and never deallocated (hence the name).

This Oracle article succinctly presents the working and parameterization of the HotSpot GC and advises you to augment this space if you load many classes (this is typically the case for application servers and some IDE like Eclipse) :

The permanent generation does not have a noticeable impact on garbage collector performance for most applications. However, some applications dynamically generate and load many classes; for example, some implementations of JavaServer Pages (JSP) pages. These applications may need a larger permanent generation to hold the additional classes. If so, the maximum permanent generation size can be increased with the command-line option -XX:MaxPermSize=.

Note that this other Oracle documentation lists the other HotSpot arguments.

Update : Starting with Java 8, both the permgen space and this setting are gone. The memory model used for loaded classes and methods is different and isn't limited (with default settings). You should not see this error any more.

Java OCR implementation

If you are looking for a very extensible option or have a specific problem domain you could consider rolling your own using the Java Object Oriented Neural Engine. Another JOONE reference.

I used it successfully in a personal project to identify the letter from an image such as this, you can find all the source for the OCR component of my application on github, here.

What does the Java assert keyword do, and when should it be used?

An assertion allows for detecting defects in the code. You can turn on assertions for testing and debugging while leaving them off when your program is in production.

Why assert something when you know it is true? It is only true when everything is working properly. If the program has a defect, it might not actually be true. Detecting this earlier in the process lets you know something is wrong.

An assert statement contains this statement along with an optional String message.

The syntax for an assert statement has two forms:

assert boolean_expression;
assert boolean_expression: error_message;

Here are some basic rules which govern where assertions should be used and where they should not be used. Assertions should be used for:

  1. Validating input parameters of a private method. NOT for public methods. public methods should throw regular exceptions when passed bad parameters.

  2. Anywhere in the program to ensure the validity of a fact which is almost certainly true.

For example, if you are sure that it will only be either 1 or 2, you can use an assertion like this:

...
if (i == 1)    {
    ...
}
else if (i == 2)    {
    ...
} else {
    assert false : "cannot happen. i is " + i;
}
...
  1. Validating post conditions at the end of any method. This means, after executing the business logic, you can use assertions to ensure that the internal state of your variables or results is consistent with what you expect. For example, a method that opens a socket or a file can use an assertion at the end to ensure that the socket or the file is indeed opened.

Assertions should not be used for:

  1. Validating input parameters of a public method. Since assertions may not always be executed, the regular exception mechanism should be used.

  2. Validating constraints on something that is input by the user. Same as above.

  3. Should not be used for side effects.

For example this is not a proper use because here the assertion is used for its side effect of calling of the doSomething() method.

public boolean doSomething() {
...    
}
public void someMethod() {       
assert doSomething(); 
}

The only case where this could be justified is when you are trying to find out whether or not assertions are enabled in your code:   

boolean enabled = false;    
assert enabled = true;    
if (enabled) {
    System.out.println("Assertions are enabled");
} else {
    System.out.println("Assertions are disabled");
}

Error: 10 $digest() iterations reached. Aborting! with dynamic sortby predicate

i had the similar error, because i had defined

ng-class="GetLink()"

instead of

ng-click="GetLink()"

What is the function of FormulaR1C1?

I find the most valuable feature of .FormulaR1C1 is sheer speed. Versus eg a couple of very large loops filling some data into a sheet, If you can convert what you are doing into a .FormulaR1C1 form. Then a single operation eg myrange.FormulaR1C1 = "my particular formuala" is blindingly fast (can be a thousand times faster). No looping and counting - just fill the range at high speed.

Trigger a button click with JavaScript on the Enter key in a text box

Short working pure JS

txtSearch.onkeydown= e => (e.key=="Enter") ? btnSearch.click() : 1

_x000D_
_x000D_
txtSearch.onkeydown= e => (e.key=="Enter") ? btnSearch.click() : 1

function doSomething() {
  console.log('');
}
_x000D_
<input type="text" id="txtSearch" />
<input type="button" id="btnSearch" value="Search" onclick="doSomething();" />
_x000D_
_x000D_
_x000D_

Difference between try-catch and throw in java

try - Add sensitive code catch - to handle exception finally - always executed whether exception caught or not. Associated with try -catch. Used to close the resource which we opened in try block throw - To handover our created exception to JVM manually. Used to throw customized exception throws - To delegate the responsibility of exception handling to caller method or main method.

Reverse Contents in Array

for(i=0;i<((s3)/2);i++)
{         
    z=s2[i];
    s2[i]=s2[(s3-1)-i];
    s2[(s3-1)-i]=z;
}

Passing ArrayList through Intent

//arraylist/Pojo you can Pass using bundle  like this 
Intent intent = new Intent(MainActivity.this, SecondActivity.class);
Bundle args = new Bundle();
                        args.putSerializable("imageSliders",(Serializable)allStoriesPojo.getImageSliderPojos());
                        intent.putExtra("BUNDLE",args);
 startActivity(intent); 


Get SecondActivity like this
  Intent intent = getIntent();
        Bundle args = intent.getBundleExtra("BUNDLE");
String filter = bundle.getString("imageSliders");

//Happy coding

Google Maps Android API v2 - Interactive InfoWindow (like in original android google maps)

Here's my take on the problem. I create AbsoluteLayout overlay which contains Info Window (a regular view with every bit of interactivity and drawing capabilities). Then I start Handler which synchronizes the info window's position with position of point on the map every 16 ms. Sounds crazy, but actually works.

Demo video: https://www.youtube.com/watch?v=bT9RpH4p9mU (take into account that performance is decreased because of emulator and video recording running simultaneously).

Code of the demo: https://github.com/deville/info-window-demo

An article providing details (in Russian): http://habrahabr.ru/post/213415/

Better way to generate array of all letters in the alphabet

Simplicity is a virtue. Use this naturally readable array:

char alphabet[] = {'a', 'b', 'c', 'd', 'e', 'f', 'g', 'h', 'i', 'j', 'k', 'l', 'm', 'n', 'o', 'p', 'q', 'r', 's', 't', 'u', 'v', 'w', 'x', 'y', 'z'};

How do I put the image on the right side of the text in a UIButton?

Thanks to Vitaliy Gozhenko

I just want to add that you can add IB_DESIGNABLE before your button @interface and set your button class in storyborad. Then you can watch it layout in real time without app launch just at interface building stage

enter image description here

Change div height on button click

_x000D_
_x000D_
var ww1 = "";_x000D_
var ww2 = 0;_x000D_
var myVar1 ;_x000D_
var myVar2 ;_x000D_
function wm1(){_x000D_
  myVar1 =setInterval(w1, 15);_x000D_
}_x000D_
function wm2(){_x000D_
  myVar2 =setInterval(w2, 15);_x000D_
}_x000D_
function w1(){_x000D_
 ww1=document.getElementById('chartdiv').style.height;_x000D_
 ww2= ww1.replace("px", ""); _x000D_
    if(parseFloat(ww2) <= 200){_x000D_
document.getElementById('chartdiv').style.height = (parseFloat(ww2)+5) + 'px';_x000D_
    }else{_x000D_
      clearInterval(myVar1);_x000D_
    }_x000D_
}_x000D_
function w2(){_x000D_
 ww1=document.getElementById('chartdiv').style.height;_x000D_
 ww2= ww1.replace("px", ""); _x000D_
    if(parseFloat(ww2) >= 50){_x000D_
document.getElementById('chartdiv').style.height = (parseFloat(ww2)-5) + 'px';_x000D_
    }else{_x000D_
      clearInterval(myVar2);_x000D_
    }_x000D_
}
_x000D_
<html>_x000D_
  <head>    _x000D_
  </head>_x000D_
_x000D_
<body >_x000D_
    <button type="button" onClick = "wm1()">200px</button>_x000D_
    <button type="button" onClick = "wm2()">50px</button>_x000D_
    <div id="chartdiv" style="width: 100%; height: 50px; background-color:#ccc"></div>_x000D_
  _x000D_
  <div id="demo"></div>_x000D_
</body>
_x000D_
_x000D_
_x000D_

How to a convert a date to a number and back again in MATLAB

Use DATESTR

>> datestr(40189)
ans =
12-Jan-0110

Unfortunately, Excel starts counting at 1-Jan-1900. Find out how to convert serial dates from Matlab to Excel by using DATENUM

>> datenum(2010,1,11)
ans =
      734149
>> datenum(2010,1,11)-40189
ans =
      693960
>> datestr(40189+693960)
ans =
11-Jan-2010

In other words, to convert any serial Excel date, call

datestr(excelSerialDate + 693960)

EDIT

To get the date in mm/dd/yyyy format, call datestr with the specified format

excelSerialDate = 40189;
datestr(excelSerialDate + 693960,'mm/dd/yyyy')
ans =
01/11/2010

Also, if you want to get rid of the leading zero for the month, you can use REGEXPREP to fix things

excelSerialDate = 40189;
regexprep(datestr(excelSerialDate + 693960,'mm/dd/yyyy'),'^0','')
ans =
1/11/2010

pip installs packages successfully, but executables not found from command line

When you install Python or Python3 using MacOS installer (downloaded from Python website) - it adds an exporter to your ~/.profile script. All you need to do is just source it. Restarting all the terminals should also do the trick.

WARNING - I believe it's better to just use pip3 with Python3 - for future benefits.

If you already have Python3 installed, the following steps work for me on macOS Mojave:

  1. Install ansible first using sudo - sudo -H pip3 install ansible

  2. you create a symlink to the Python's bin path

sudo ln -s /Library/Frameworks/Python.framework/Versions/Current/bin /Library/Frameworks/Python.framework/current_python_bin

and staple it to .profile

export PATH=$PATH:/Library/Frameworks/Python.framework/current_python_bin

  1. run source ~/.profile and restart all terminal shells.

  2. Type ansible --version

css divide width 100% to 3 column

In case you wonder, In Bootstrap templating system (which is very accurate), here is how they divide the columns when you apply the class .col-md-4 (1/3 of the 12 column system)

CSS

.col-md-4{
    float: left;
    width: 33.33333333%;
}

I'm not a fan of float, but if you really want your element to be perfectly 1/3 of your page, then you don't have a choice because sometimes when you use inline-block element, browser can consider space in your HTML as a 1px space which would break your perfect 1/3. Hope it helped !

Go test string contains substring

To compare, there are more options:

import (
    "fmt"
    "regexp"
    "strings"
)

const (
    str    = "something"
    substr = "some"
)

// 1. Contains
res := strings.Contains(str, substr)
fmt.Println(res) // true

// 2. Index: check the index of the first instance of substr in str, or -1 if substr is not present
i := strings.Index(str, substr)
fmt.Println(i) // 0

// 3. Split by substr and check len of the slice, or length is 1 if substr is not present
ss := strings.Split(str, substr)
fmt.Println(len(ss)) // 2

// 4. Check number of non-overlapping instances of substr in str
c := strings.Count(str, substr)
fmt.Println(c) // 1

// 5. RegExp
matched, _ := regexp.MatchString(substr, str)
fmt.Println(matched) // true

// 6. Compiled RegExp
re = regexp.MustCompile(substr)
res = re.MatchString(str)
fmt.Println(res) // true

Benchmarks: Contains internally calls Index, so the speed is almost the same (btw Go 1.11.5 showed a bit bigger difference than on Go 1.14.3).

BenchmarkStringsContains-4              100000000               10.5 ns/op             0 B/op          0 allocs/op
BenchmarkStringsIndex-4                 117090943               10.1 ns/op             0 B/op          0 allocs/op
BenchmarkStringsSplit-4                  6958126               152 ns/op              32 B/op          1 allocs/op
BenchmarkStringsCount-4                 42397729                29.1 ns/op             0 B/op          0 allocs/op
BenchmarkStringsRegExp-4                  461696              2467 ns/op            1326 B/op         16 allocs/op
BenchmarkStringsRegExpCompiled-4         7109509               168 ns/op               0 B/op          0 allocs/op

npm install vs. update - what's the difference?

Many distinctions have already been mentioned. Here is one more:

Running npm install at the top of your source directory will run various scripts: prepublish, preinstall, install, postinstall. Depending on what these scripts do, a npm install may do considerably more work than just installing dependencies.

I've just had a use case where prepublish would call make and the Makefile was designed to fetch dependencies if the package.json got updated. Calling npm install from within the Makefile would have lead to an infinite recursion, while calling npm update worked just fine, installing all dependencies so that the build could proceed even if make was called directly.

How to run test cases in a specified file?

go test -v -timeout 30s <path_to_package> -run ^(TestFuncRegEx)
  • The TestFunc must be inside a go test file in that package
  • We can provide a regular expression to match a set of test cases or just the exact test case function to run a single test case. For instance -run TestCaseFunc

How do you use the "WITH" clause in MySQL?

In Sql the with statement specifies a temporary named result set, known as a common table expression (CTE). It can be used for recursive queries, but in this case, it specifies as subset. If mysql allows for subselectes i would try

select t1.* 
from  (
            SELECT  article.*, 
                    userinfo.*, 
                    category.* 
            FROM    question INNER JOIN 
                    userinfo ON userinfo.user_userid=article.article_ownerid INNER JOIN category ON article.article_categoryid=category.catid
            WHERE   article.article_isdeleted = 0
     ) t1
ORDER BY t1.article_date DESC Limit 1, 3

How to find foreign key dependencies in SQL Server?

Just a note for @"John Sansom" answer,

If the foreign key dependencies are sought, I think that the PT Where clause should be:

i1.CONSTRAINT_TYPE = 'FOREIGN KEY'  -- instead of 'PRIMARY KEY'

and its the ON condition:

ON PT.TABLE_NAME = FK.TABLE_NAME – instead of PK.TABLE_NAME

As commonly is used the primary key of the foreign table, I think this issue has not been noticed before.

"sed" command in bash

sed is the Stream EDitor. It can do a whole pile of really cool things, but the most common is text replacement.

The s,%,$,g part of the command line is the sed command to execute. The s stands for substitute, the , characters are delimiters (other characters can be used; /, : and @ are popular). The % is the pattern to match (here a literal percent sign) and the $ is the second pattern to match (here a literal dollar sign). The g at the end means to globally replace on each line (otherwise it would only update the first match).