Programs & Examples On #Blitz++

Blitz++ is a meta-template library for array manipulation in C++ with a speed comparable to Fortran implementations, while preserving an object-oriented interface.

How to rebase local branch onto remote master

1.Update Master first...

git checkout [master branch]
git pull [master branch]

2.Now rebase source-branch with master branch

git checkout [source branch]
git rebase [master branch]
git pull [source branch] (remote/source branch)
git push [source branch]

IF source branch does not yet exist on remote then do:

git push -u origin [source branch]

"et voila..."

How to move files from one git repo to another (not a clone), preserving history

The one I always use is here http://blog.neutrino.es/2012/git-copy-a-file-or-directory-from-another-repository-preserving-history/ . Simple and fast.

For compliance with stackoverflow standards, here is the procedure:

mkdir /tmp/mergepatchs
cd ~/repo/org
export reposrc=myfile.c #or mydir
git format-patch -o /tmp/mergepatchs $(git log $reposrc|grep ^commit|tail -1|awk '{print $2}')^..HEAD $reposrc
cd ~/repo/dest
git am /tmp/mergepatchs/*.patch

What is the perfect counterpart in Python for "while not EOF"

While there are suggestions above for "doing it the python way", if one wants to really have a logic based on EOF, then I suppose using exception handling is the way to do it --

try:
    line = raw_input()
    ... whatever needs to be done incase of no EOF ...
except EOFError:
    ... whatever needs to be done incase of EOF ...

Example:

$ echo test | python -c "while True: print raw_input()"
test
Traceback (most recent call last):
  File "<string>", line 1, in <module> 
EOFError: EOF when reading a line

Or press Ctrl-Z at a raw_input() prompt (Windows, Ctrl-Z Linux)

How to get the current loop index when using Iterator?

You can use ListIterator to do the counting:

final List<String> list = Arrays.asList("zero", "one", "two", "three");

for (final ListIterator<String> it = list.listIterator(); it.hasNext();) {
    final String s = it.next();
    System.out.println(it.previousIndex() + ": " + s);
}

Indexes of all occurrences of character in a string

This is a java 8 solution.

public int[] solution (String s, String subString){
        int initialIndex = s.indexOf(subString);
        List<Integer> indexList = new ArrayList<>();
        while (initialIndex >=0){
            indexList.add(initialIndex);
            initialIndex = s.indexOf(subString, initialIndex+1);
        }
        int [] intA = indexList.stream().mapToInt(i->i).toArray();
        return intA;
    }

How to get the current TimeStamp?

In Qt 4.7, there is the QDateTime::currentMSecsSinceEpoch() static function, which does exactly what you need, without any intermediary steps. Hence I'd recommend that for projects using Qt 4.7 or newer.

JPA and Hibernate - Criteria vs. JPQL or HQL

HQL can cause security concerns like SQL injection.

Qt - reading from a text file

You have to replace string line

QString line = in.readLine();

into while:

QFile file("/home/hamad/lesson11.txt");
if(!file.open(QIODevice::ReadOnly)) {
    QMessageBox::information(0, "error", file.errorString());
}

QTextStream in(&file);

while(!in.atEnd()) {
    QString line = in.readLine();    
    QStringList fields = line.split(",");    
    model->appendRow(fields);    
}

file.close();

Java integer to byte array

If you're using apache-commons

public static byte[] toByteArray(int value) {
    byte result[] = new byte[4];
    return Conversion.intToByteArray(value, 0, result, 0, 4);
}

text-overflow: ellipsis not working

word-wrap: break-word;

this and only this did the job for me for a

<pre> </pre> 

tag

everthing else failed to do the ellipsis....

MySQL select all rows from last month until (now() - 1 month), for comparative purposes

Simple code please check

SELECT * FROM table_name WHERE created <= (NOW() - INTERVAL 1 MONTH)

How to prevent robots from automatically filling up a form?

With the emergence of headless browsers (like phantomjs) which can emulate anything, you can't suppose that :

  • spam bots do not use javascript,
  • you can track mouse events to detect bot,
  • they won't see that a field is visually hidden,
  • they won't wait a given time before submitting.

If that used to be true, it is no longer true.

If you wan't an user friendly solution, just give them a beautiful "i am a spammer" submit button:

 <input type="submit" name="ignore" value="I am a spammer!" />
 <input type="image" name="accept" value="submit.png" alt="I am not a spammer" />

Of course you can play with two image input[type=image] buttons, changing the order after each load, the text alternatives, the content of the images (and their size) or the name of the buttons; which will require some server work.

 <input type="image" name="random125454548" value="random125454548.png"
      alt="I perfectly understand that clicking on this link will send the
      e-mail to the expected person" />
 <input type="image" name="random125452548" value="random125452548.png"
      alt="I really want to cancel the submission of this form" />

For accessibility reasons, you have to put a correct textual alternative, but I think that a long sentence is better for screenreaders users than being considered as a bot.

Additional note: those examples illustrate that understanding english (or any language), and having to make a simple choice, is harder for a spambot than : waiting 10 seconds, handling CSS or javascript, knowing that a field is hidden, emulating mouse move or emulating keyboard typing, ...

convert iso date to milliseconds in javascript

Another possible solution is to compare current date with January 1, 1970, you can get January 1, 1970 by new Date(0);

var date = new Date(); 
var myDate= date - new Date(0);

Understanding passport serialize deserialize

  1. Where does user.id go after passport.serializeUser has been called?

The user id (you provide as the second argument of the done function) is saved in the session and is later used to retrieve the whole object via the deserializeUser function.

serializeUser determines which data of the user object should be stored in the session. The result of the serializeUser method is attached to the session as req.session.passport.user = {}. Here for instance, it would be (as we provide the user id as the key) req.session.passport.user = {id: 'xyz'}

  1. We are calling passport.deserializeUser right after it where does it fit in the workflow?

The first argument of deserializeUser corresponds to the key of the user object that was given to the done function (see 1.). So your whole object is retrieved with help of that key. That key here is the user id (key can be any key of the user object i.e. name,email etc). In deserializeUser that key is matched with the in memory array / database or any data resource.

The fetched object is attached to the request object as req.user

Visual Flow

passport.serializeUser(function(user, done) {
    done(null, user.id);
});              ¦
                 ¦ 
                 ¦
                 +--------------------? saved to session
                                   ¦    req.session.passport.user = {id: '..'}
                                   ¦
                                   ?           
passport.deserializeUser(function(id, done) {
                   +---------------+
                   ¦
                   ? 
    User.findById(id, function(err, user) {
        done(err, user);
    });            +--------------? user object attaches to the request as req.user   
});

How to Convert UTC Date To Local time Zone in MySql Select Query

SELECT CONVERT_TZ() will work for that.but its not working for me.

Why, what error do you get?

SELECT CONVERT_TZ(displaytime,'GMT','MET');

should work if your column type is timestamp, or date

http://dev.mysql.com/doc/refman/5.0/en/date-and-time-functions.html#function_convert-tz

Test how this works:

SELECT CONVERT_TZ(a_ad_display.displaytime,'+00:00','+04:00');

Check your timezone-table

SELECT * FROM mysql.time_zone;
SELECT * FROM mysql.time_zone_name;

http://dev.mysql.com/doc/refman/5.5/en/time-zone-support.html

If those tables are empty, you have not initialized your timezone tables. According to link above you can use mysql_tzinfo_to_sql program to load the Time Zone Tables. Please try this

shell> mysql_tzinfo_to_sql /usr/share/zoneinfo

or if not working read more: http://dev.mysql.com/doc/refman/5.5/en/mysql-tzinfo-to-sql.html

What are the best JVM settings for Eclipse?

-startup
../../../plugins/org.eclipse.equinox.launcher_1.2.0.v20110502.jar
--launcher.library
../../../plugins/org.eclipse.equinox.launcher.cocoa.macosx_1.1.100.v20110502
-showsplash
org.eclipse.platform
--launcher.XXMaxPermSize
256m
--launcher.defaultAction
openFile
-vmargs
-Xms128m
-Xmx512m
-XX:MaxPermSize=256m
-Xdock:icon=../Resources/Eclipse.icns
-XstartOnFirstThread
-Dorg.eclipse.swt.internal.carbon.smallFonts
-Dcom.sun.management.jmxremote
-Declipse.p2.unsignedPolicy=allow

And these setting have worked like a charm for me. I am running OS X10.6 , Eclipse 3.7 Indigo , JDK1.6.0_24

Lint: How to ignore "<key> is not translated in <language>" errors?

Add following to your gradle file in android section

    lintOptions {
       disable 'MissingTranslation'
    }

How to filter wireshark to see only dns queries that are sent/received from/by my computer?

use this filter:

(dns.flags.response == 0) and (ip.src == 159.25.78.7)

what this query does is it only gives dns queries originated from your ip

How to run a Runnable thread in Android at defined intervals?

An interesting example is you can continuously see a counter/stop-watch running in separate thread. Also showing GPS-Location. While main activity User Interface Thread is already there.

Excerpt:

try {    
    cnt++; scnt++;
    now=System.currentTimeMillis();
    r=rand.nextInt(6); r++;    
    loc=lm.getLastKnownLocation(best);    

    if(loc!=null) { 
        lat=loc.getLatitude();
        lng=loc.getLongitude(); 
    }    

    Thread.sleep(100); 
    handler.sendMessage(handler.obtainMessage());
} catch (InterruptedException e) {   
    Toast.makeText(this, "Error="+e.toString(), Toast.LENGTH_LONG).show();
}

To look at code see here:

Thread example displaying GPS Location and Current Time runnable alongside main-activity's User Interface Thread

standard size for html newsletter template

Ideally the email content should be about 550px wide to fit within most email clients preview window. If you know for sure your target market can view bigger then you can design bigger. Loads of email examples over on http://www.beautiful-email-newsletters.com/

How does one remove a Docker image?

In my case the probleme is that I have tow images withe same name the solution is to add the tag after the name or the id

sudo docker rmi <NAME>:<TAG>

ex:

sudo docker rmi php:7.0.4-fpm

How do I shutdown, restart, or log off Windows via a bat file?

No one has mentioned -m option for remote shutdown:

shutdown -r -f -m \\machinename

Also:

  • The -r parameter causes a reboot (which is usually what you want on a remote machine, since physically starting it might be difficult).
  • The -f parameter option forces the reboot.
  • You must have appropriate privileges to shut down the remote machine, of course.

How can I format DateTime to web UTC format?

string foo = yourDateTime.ToUniversalTime()
                         .ToString("yyyy'-'MM'-'dd'T'HH':'mm':'ss'.'fff'Z'");

How do I filter an array with AngularJS and use a property of the filtered object as the ng-model attribute?

If you are using ES6 you can:

var sample = [1, 2, 3]

var result = sample.filter(elem => elem !== 2)

/* output */
[1, 3]

Also take notice filter does not update the existing array it will return a new filtered array every time.

Deprecated Gradle features were used in this build, making it incompatible with Gradle 5.0

It work for me in this issue in a project of react-native:

Deprecated Gradle features were used in this build, making it incompatible with Gradle 7.0.

244 actionable tasks: 2 executed, 242 up-to-date D8: Cannot fit requested classes in a single dex file (# fields: 67296 > 65536) com.android.builder.dexing.DexArchiveMergerException: Error while merging dex archives: The number of method references in a .dex file cannot exceed 64K. Learn how to resolve this issue at https://developer.android.com/tools/building/multidex.html ....

I Did this:

Is it possible to read from a InputStream with a timeout?

I have not used the classes from the Java NIO package, but it seems they might be of some help here. Specifically, java.nio.channels.Channels and java.nio.channels.InterruptibleChannel.

Why do symbols like apostrophes and hyphens get replaced with black diamonds on my website?

I experienced the same problem when I copied a text that has an apostrophe from a Word document to my HTML code.

To resolve the issue, all I did was deleted the particular word in my HTML and typed it directly, including the apostrophe. This action nullified the original copy and paste acton and displayed the newly typed apostrophe correctly

Action Bar's onClick listener for the Home button

you should to delete your the Override onOptionsItemSelected and replate your onCreateOptionsMenu with this code

@Override
    public boolean onCreateOptionsMenu(Menu menu) {
        // Inflate the menu; this adds items to the action bar if it is present.
        getMenuInflater().inflate(R.menu.menu_action_bar_finish_order_stop, menu);
        menu.getItem(0).setOnMenuItemClickListener(new FinishOrderStopListener(this, getApplication(), selectedChild));
        return true;

    }

php stdClass to array

Use the built in type cast functionality, simply type

$realArray = (array)$stdClass;

Get full path of a file with FileUpload Control

Check this:

<%@ Page Language="VB" AutoEventWireup="false" CodeFile="FileUp.aspx.vb" Inherits="FileUp" %>

<!DOCTYPE html PUBLIC "-//W3C//DTD XHTML 1.0 Transitional//EN" "http://www.w3.org/TR/xhtml1/DTD/xhtml1-transitional.dtd">

<html xmlns="http://www.w3.org/1999/xhtml">
<head runat="server">
    <title></title>
</head>
<body>
    <form id="form1" runat="server">
    <div>
        <asp:Label ID="Label1" runat="server"></asp:Label><br />
       <asp:FileUpload ID="FileUpload1" runat="server" /><br />
        <asp:Button ID="Button1" runat="server" Text="Upload" />
    </div>
    </form>
</body>
</html>

Code:

Partial Class FileUp
    Inherits System.Web.UI.Page
    Protected Sub Button1_Click(ByVal sender As Object, ByVal e As System.EventArgs) Handles Button1.Click
        Dim path As String
        Dim path1 As String
        path = Server.MapPath("~/")
        FileUpload1.SaveAs(path + FileUpload1.FileName)
        path1 = path + FileUpload1.FileName
        Label1.Text = path1
        Response.Write("File Uploaded successfully")
    End Sub
End Class

Using reflection in Java to create a new instance with the reference variable type set to the new instance class name?

If you knew the Class of ImplementationType you could create an instance of it. So what you are trying to do is not possible.

How do I create/edit a Manifest file?

As ibram stated, add the manifest thru solution explorer:

enter image description here

This creates a default manifest. Now, edit the manifest.

  • Update the assemblyIdentity name as your application.
  • Ask users to trust your application

enter image description here

  • Add supported OS

enter image description here

Closing JFrame with button click

It appears to me that you have two issues here. One is that JFrame does not have a close method, which has been addressed in the other answers.

The other is that you're having trouble referencing your JFrame. Within actionPerformed, super refers to ActionListener. To refer to the JFrame instance there, use MyExtendedJFrame.super instead (you should also be able to use MyExtendedJFrame.this, as I see no reason why you'd want to override the behaviour of dispose or setVisible).

Is there a way to get element by XPath using JavaScript in Selenium WebDriver?

Assuming your objective is to develop and test your xpath queries for screen maps. Then either use Chrome's developer tools. This allows you to run the xpath query to show the matches. Or in Firefox >9 you can do the same thing with the Web Developer Tools console. In earlier version use x-path-finder or Firebug.

How to search file text for a pattern and replace it with a given value

require 'trollop'

opts = Trollop::options do
  opt :output, "Output file", :type => String
  opt :input, "Input file", :type => String
  opt :ss, "String to search", :type => String
  opt :rs, "String to replace", :type => String
end

text = File.read(opts.input)
text.gsub!(opts.ss, opts.rs)
File.open(opts.output, 'w') { |f| f.write(text) }

How to TryParse for Enum value?

In the end you have to implement this around Enum.GetNames:

public bool TryParseEnum<T>(string str, bool caseSensitive, out T value) where T : struct {
    // Can't make this a type constraint...
    if (!typeof(T).IsEnum) {
        throw new ArgumentException("Type parameter must be an enum");
    }
    var names = Enum.GetNames(typeof(T));
    value = (Enum.GetValues(typeof(T)) as T[])[0];  // For want of a better default
    foreach (var name in names) {
        if (String.Equals(name, str, caseSensitive ? StringComparison.Ordinal : StringComparison.OrdinalIgnoreCase)) {
            value = (T)Enum.Parse(typeof(T), name);
            return true;
        }
    }
    return false;
}

Additional notes:

  • Enum.TryParse is included in .NET 4. See here http://msdn.microsoft.com/library/dd991876(VS.100).aspx
  • Another approach would be to directly wrap Enum.Parse catching the exception thrown when it fails. This could be faster when a match is found, but will likely to slower if not. Depending on the data you are processing this may or may not be a net improvement.

EDIT: Just seen a better implementation on this, which caches the necessary information: http://damieng.com/blog/2010/10/17/enums-better-syntax-improved-performance-and-tryparse-in-net-3-5

Print all but the first three columns

I can't believe nobody offered plain shell:

while read -r a b c d; do echo "$d"; done < file

White space showing up on right side of page when background image should extend full length of page

I see the question has been answered to a general standard, but when I looked at your site I noticed there is still a horizontal scroll-bar. I also notice the reason for this: You have used the code:

.homepageconference .container {
padding-left: 12%;
}

which is being used alongside code stating that the element has a width of 100%, causing an element with a total width of 112% of screen size. To fix this, either remove the padding, replace the padding with a margin of 12% for the same effect, or change the width (or max-width) of the element to 88%. This occurs in main.css at line 343. Hope this helps!

What's a good (free) visual merge tool for Git? (on windows)

Another free option is jmeld: http://keeskuip.home.xs4all.nl/jmeld/

It's a java tool and could therefore be used on several platforms.

But (as Preet mentioned in his answer), free is not always the best option. The best diff/merge tool I ever came across is Araxis Merge. Standard edition is available for 99 EUR which is not that much.

They also provide a documentation for how to integrate Araxis with msysGit.

If you want to stick to a free tool, JMeld comes pretty close to Araxis.

Splitting on last delimiter in Python string?

Use .rsplit() or .rpartition() instead:

s.rsplit(',', 1)
s.rpartition(',')

str.rsplit() lets you specify how many times to split, while str.rpartition() only splits once but always returns a fixed number of elements (prefix, delimiter & postfix) and is faster for the single split case.

Demo:

>>> s = "a,b,c,d"
>>> s.rsplit(',', 1)
['a,b,c', 'd']
>>> s.rsplit(',', 2)
['a,b', 'c', 'd']
>>> s.rpartition(',')
('a,b,c', ',', 'd')

Both methods start splitting from the right-hand-side of the string; by giving str.rsplit() a maximum as the second argument, you get to split just the right-hand-most occurrences.

Batch script to find and replace a string in text file within a minute for files up to 12 MB

A variant using Bat/Powershell (need .net framework):

replace.bat :

@echo off

call:DoReplace "Findstr" "replacestr" test.txt test1.txt
exit /b

:DoReplace
echo ^(Get-Content "%3"^) ^| ForEach-Object { $_ -replace %1, %2 } ^| Set-Content %4>Rep.ps1
Powershell.exe -executionpolicy ByPass -File Rep.ps1
if exist Rep.ps1 del Rep.ps1
echo Done
pause

Appending a line to a file only if it does not already exist

The answers using grep are wrong. You need to add an -x option to match the entire line otherwise lines like #text to add will still match when looking to add exactly text to add.

So the correct solution is something like:

grep -qxF 'include "/configs/projectname.conf"' foo.bar || echo 'include "/configs/projectname.conf"' >> foo.bar

Ordering by specific field value first

There's also the MySQL FIELD function.

If you want complete sorting for all possible values:

SELECT id, name, priority
FROM mytable
ORDER BY FIELD(name, "core", "board", "other")

If you only care that "core" is first and the other values don't matter:

SELECT id, name, priority
FROM mytable
ORDER BY FIELD(name, "core") DESC

If you want to sort by "core" first, and the other fields in normal sort order:

SELECT id, name, priority
FROM mytable
ORDER BY FIELD(name, "core") DESC, priority

There are some caveats here, though:

First, I'm pretty sure this is mysql-only functionality - the question is tagged mysql, but you never know.

Second, pay attention to how FIELD() works: it returns the one-based index of the value - in the case of FIELD(priority, "core"), it'll return 1 if "core" is the value. If the value of the field is not in the list, it returns zero. This is why DESC is necessary unless you specify all possible values.

Not Able To Debug App In Android Studio

In my case near any line a red circle appeared with a cross and red line with a message: "No executable code found at line ..." like in Android studio gradle breakpoint No executable code found at line.

A problem appeared after updating of build.gradle. We included Kotlin support, so a number of methods exceeded 64K. Problem lines:

buildTypes {
    debug {
        minifyEnabled true

Change them to:

buildTypes {
    debug {
        minifyEnabled false
        debuggable true

Then sync a gradle with a button "Sync Project with Gradle Files". If after restarting of your application you will get an error: "Error:The number of method references in a .dex file cannot exceed 64K. Learn how to resolve this issue at https://developer.android.com/tools/building/multidex.html", then, like in The number of method references in a .dex file cannot exceed 64k API 17 add the following lines to build.gradle:

android {

    defaultConfig {
        ...

        // Enabling multidex support.
        multiDexEnabled true
    }
    ...
}

dependencies {
    implementation 'com.android.support:multidex:1.0.2'
}

UPDATE

According to https://developer.android.com/studio/build/multidex.html do the following to enable multidex support below Android 5.0. Else it won't start in these devices.

Open AndroidManifest and find tag <application>. Near android:name= is a reference to an Application class. Open this class. Extend Application class with MultiDexApplication so:

public class MyApplication extends MultiDexApplication { ... }

If no Application class set, write so:

<application
        android:name="android.support.multidex.MultiDexApplication" >
    ...
</application>

How to get value of a div using javascript

DIVs do not have a value property.

Technically, according to the DTDs, they shouldn't have a value attribute either, but generally you'll want to use .getAttribute() in this case:

function overlay()
{
    var cookieValue = document.getElementById('demo').getAttribute('value');
    alert(cookieValue);
}

How to use the IEqualityComparer

IEquatable<T> can be a much easier way to do this with modern frameworks.

You get a nice simple bool Equals(T other) function and there's no messing around with casting or creating a separate class.

public class Person : IEquatable<Person>
{
    public Person(string name, string hometown)
    {
        this.Name = name;
        this.Hometown = hometown;
    }

    public string Name { get; set; }
    public string Hometown { get; set; }

    // can't get much simpler than this!
    public bool Equals(Person other)
    {
        return this.Name == other.Name && this.Hometown == other.Hometown;
    }

    public override int GetHashCode()
    {
        return Name.GetHashCode();  // see other links for hashcode guidance 
    }
}

Note you DO have to implement GetHashCode if using this in a dictionary or with something like Distinct.

PS. I don't think any custom Equals methods work with entity framework directly on the database side (I think you know this because you do AsEnumerable) but this is a much simpler method to do a simple Equals for the general case.

If things don't seem to be working (such as duplicate key errors when doing ToDictionary) put a breakpoint inside Equals to make sure it's being hit and make sure you have GetHashCode defined (with override keyword).

ReferenceError: describe is not defined NodeJs

if you are using vscode, want to debug your files

I used tdd before, it throw ReferenceError: describe is not defined

But, when I use bdd, it works!

waste half day to solve it....

    {
      "type": "node",
      "request": "launch",
      "name": "Mocha Tests",
      "program": "${workspaceFolder}/node_modules/mocha/bin/_mocha",
      "args": [
        "-u",
        "bdd",// set to bdd, not tdd
        "--timeout",
        "999999",
        "--colors",
        "${workspaceFolder}/test/**/*.js"
      ],
      "internalConsoleOptions": "openOnSessionStart"
},

ASP.NET MVC Custom Error Handling Application_Error Global.asax?

I have problem with this error handling approach: In case of web.config:

<customErrors mode="On"/>

The error handler is searching view Error.shtml and the control flow step in to Application_Error global.asax only after exception

System.InvalidOperationException: The view 'Error' or its master was not found or no view engine supports the searched locations. The following locations were searched: ~/Views/home/Error.aspx ~/Views/home/Error.ascx ~/Views/Shared/Error.aspx ~/Views/Shared/Error.ascx ~/Views/home/Error.cshtml ~/Views/home/Error.vbhtml ~/Views/Shared/Error.cshtml ~/Views/Shared/Error.vbhtml at System.Web.Mvc.ViewResult.FindView(ControllerContext context) ....................

So

 Exception exception = Server.GetLastError();
  Response.Clear();
  HttpException httpException = exception as HttpException;

httpException is always null then customErrors mode="On" :( It is misleading Then <customErrors mode="Off"/> or <customErrors mode="RemoteOnly"/> the users see customErrors html, Then customErrors mode="On" this code is wrong too


Another problem of this code that

Response.Redirect(String.Format("~/Error/{0}/?message={1}", action, exception.Message));

Return page with code 302 instead real error code(402,403 etc)

Does `anaconda` create a separate PYTHONPATH variable for each new environment?

No, the only thing that needs to be modified for an Anaconda environment is the PATH (so that it gets the right Python from the environment bin/ directory, or Scripts\ on Windows).

The way Anaconda environments work is that they hard link everything that is installed into the environment. For all intents and purposes, this means that each environment is a completely separate installation of Python and all the packages. By using hard links, this is done efficiently. Thus, there's no need to mess with PYTHONPATH because the Python binary in the environment already searches the site-packages in the environment, and the lib of the environment, and so on.

Invalid hook call. Hooks can only be called inside of the body of a function component

If all the above doesn't work, especially if having big size dependency (like my case), both building and loading were taking a minimum of 15 seconds, so it seems the delay gave a false message "Invalid hook call." So what you can do is give some time to ensure the build is completed before testing.

R: numeric 'envir' arg not of length one in predict()

There are several problems here:

  1. The newdata argument of predict() needs a predictor variable. You should thus pass it values for Coupon, instead of Total, which is the response variable in your model.

  2. The predictor variable needs to be passed in as a named column in a data frame, so that predict() knows what the numbers its been handed represent. (The need for this becomes clear when you consider more complicated models, having more than one predictor variable).

  3. For this to work, your original call should pass df in through the data argument, rather than using it directly in your formula. (This way, the name of the column in newdata will be able to match the name on the RHS of the formula).

With those changes incorporated, this will work:

model <- lm(Total ~ Coupon, data=df)
new <- data.frame(Coupon = df$Coupon)
predict(model, newdata = new, interval="confidence")

Getting a machine's external IP address with Python

If you are not interested in hitting any url to get public ip, I think following code can help you to get public ip using python of your machine

import os
externalIP  = os.popen("ifconfig | grep 'inet' | cut -d: -f2 | awk '{print $2}' | sed -n 3p").readline()
print externalIP

sed -n 3p line varies as per the network you are using for connecting device.

I was facing same issue, I was needed public ip of iot device which is hitting my server. but public ip is totally different in ifconfig command and ip i am getting in server from request object. after this I am adding extra param into my request to send ip of device to my server.

hope this is helpful

macro for Hide rows in excel 2010

You almost got it. You are hiding the rows within the active sheet. which is okay. But a better way would be add where it is.

Rows("52:55").EntireRow.Hidden = False

becomes

activesheet.Rows("52:55").EntireRow.Hidden = False

i've had weird things happen without it. As for making it automatic. You need to use the worksheet_change event within the sheet's macro in the VBA editor (not modules, double click the sheet1 to the far left of the editor.) Within that sheet, use the drop down menu just above the editor itself (there should be 2 listboxes). The listbox to the left will have the events you are looking for. After that just throw in the macro. It should look like the below code,

Private Sub Worksheet_Change(ByVal Target As Range)
test1
end Sub

That's it. Anytime you change something, it will run the macro test1.

What is the curl error 52 "empty reply from server"?

I've had this problem before. Figured out I had another application using the same port (3000).

Easy way to find this out:

In the terminal, type netstat -a -p TCP -n | grep 3000 (substitute the port you're using for the '3000'). If there is more than one listening, something else is already occupying that port. You should stop that process or change the port for your new process.

Postgresql: password authentication failed for user "postgres"

This was frustrating, most of the above answers are correct but they fail to mention you have to restart the database service before the changes in the pg_hba.conf file will take affect.

so if you make the changes as mentioned above:

local all postgres ident

then restart as root ( on centos its something like service service postgresql-9.2 restart ) now you should be able to access the db as the user postgres

$psql
psql (9.2.4)
Type "help" for help.

postgres=# 

Hope this adds info for new postgres users

Resize image in the wiki of GitHub using Markdown

Updated:

Markdown syntax for images (external/internal):

![test](https://github.com/favicon.ico)

HTML code for sizing images (internal/external):

<img src="https://github.com/favicon.ico" width="48">

Example:

test


Old Answer:

This should work:

[[ http://url.to/image.png | height = 100px ]]

Source: https://guides.github.com/features/mastering-markdown/

Select rows where column is null

for some reasons IS NULL may not work with some column data type i was in need to get all the employees that their English full name is missing ,I've used :

**SELECT emp_id ,Full_Name_Ar,Full_Name_En from employees where Full_Name_En = ' ' or Full_Name_En is null **

How to make Toolbar transparent?

I implemented translucent Toolbar by creating two Theme.AppCompat.Light.NoActionBar themes and setting colorPrimary attribute to transparent color.

1) Create one theme for opaque Toolbar:

<style name="AppTheme" parent="Theme.AppCompat.Light.NoActionBar">

    <!-- Toolbar background color -->
    <item name="colorPrimary">#ff212cff</item>

</style>

Second theme for transparent/overlay Toolbar:

<style name="AppTheme.Overlay" parent="AppTheme">
    <item name="colorPrimary">@color/transparent</item>
</style>

2) In your activity layout, put Toolbar behind content so it can be displayed in front of it:

<RelativeLayout
    xmlns:android="http://schemas.android.com/apk/res/android"
    xmlns:app="http://schemas.android.com/apk/res-auto"
    xmlns:tools="http://schemas.android.com/tools"
    android:layout_width="match_parent"
    android:layout_height="match_parent"
    android:orientation="vertical">

    <fragment
        android:id="@+id/container"
        android:name="com.test.CustomFragment"
        android:layout_width="match_parent"
        android:layout_height="match_parent"/>

    <android.support.v7.widget.Toolbar
        android:id="@+id/toolbar"
        android:layout_width="match_parent"
        android:layout_height="wrap_content"
        android:background="?attr/colorPrimary"
        android:minHeight="?attr/actionBarSize"
        app:popupTheme="@style/ThemeOverlay.AppCompat.Light"
        app:theme="@style/ThemeOverlay.AppCompat.Dark.ActionBar"/>

</RelativeLayout>

3) Apply the transparent theme to your acivity in AndroidManifest.xml

    <activity
        android:name="com.test.TransparentActivity"
        android:parentActivityName="com.test.HomeActivity"
        android:theme="@style/AppTheme.Overlay" >
        <meta-data
            android:name="android.support.PARENT_ACTIVITY"
            android:value="com.test.HomeActivity" />
    </activity>

Effects of the extern keyword on C functions

As far as I remember the standard, all function declarations are considered as "extern" by default, so there is no need to specify it explicitly.

That doesn't make this keyword useless since it can also be used with variables (and it that case - it's the only solution to solve linkage problems). But with the functions - yes, it's optional.

How do I set the default font size in Vim?

The other answers are what you asked about, but in case it’s useful to anyone else, here’s how to set the font conditionally from the screen DPI (Windows only):

set guifont=default
if has('windows')
    "get dpi, strip out utf-16 garbage and new lines
    "system() converts 0x00 to 0x01 for 'platform independence'
    "should return something like 'PixelsPerXLogicalInch=192'
    "get the part from the = to the end of the line (eg '=192') and strip
    "the first character
    "and convert to a number
    let dpi = str2nr(strpart(matchstr(substitute(
        \system('wmic desktopmonitor get PixelsPerXLogicalInch /value'),
        \'\%x01\|\%x0a\|\%x0a\|\%xff\|\%xfe', '', 'g'),
        \'=.*$'), 1))
    if dpi > 100
        set guifont=high_dpi_font
    endif
endif

multiple conditions for JavaScript .includes() method

That should work even if one, and only one of the conditions is true :

var str = "bonjour le monde vive le javascript";
var arr = ['bonjour','europe', 'c++'];

function contains(target, pattern){
    var value = 0;
    pattern.forEach(function(word){
      value = value + target.includes(word);
    });
    return (value === 1)
}

console.log(contains(str, arr));

How can I change the language (to english) in Oracle SQL Developer?

With SQL Developer 4.x, the language option is to be added to ..\sqldeveloper\bin\sqldeveloper.conf, rather than ..\sqldeveloper\bin\ide.conf:

# ----- MODIFICATION BEGIN -----
AddVMOption -Duser.language=en
# ----- MODIFICATION END -----

Redirecting to a relative URL in JavaScript

I'm trying to redirect my current web site to other section on the same page, using JavaScript. This follow code work for me:

location.href='/otherSection'

jquery animate .css

Just use .animate() instead of .css() (with a duration if you want), like this:

$('#hfont1').hover(function() {
    $(this).animate({"color":"#efbe5c","font-size":"52pt"}, 1000);
}, function() {
    $(this).animate({"color":"#e8a010","font-size":"48pt"}, 1000);
});

You can test it here. Note though, you need either the jQuery color plugin, or jQuery UI included to animate the color. In the above, the duration is 1000ms, you can change it, or just leave it off for the default 400ms duration.

Java code for getting current time

try this:

final String currentTime    = String.valueOf(System.currentTimeMillis());

What’s the best way to check if a file exists in C++? (cross platform)

Be careful of race conditions: if the file disappears between the "exists" check and the time you open it, your program will fail unexpectedly.

It's better to go and open the file, check for failure and if all is good then do something with the file. It's even more important with security-critical code.

Details about security and race conditions: http://www.ibm.com/developerworks/library/l-sprace.html

jQuery CSS Opacity

try using .animate instead of .css or even just on the opacity one and leave .css on the display?? may b

jQuery(document).ready(function(){
if (jQuery('#nav .drop').animate('display') === 'block') {
    jQuery('#main').animate('opacity') = '0.6';

Pure CSS to make font-size responsive based on dynamic amount of characters

For reference, a non-CSS solution:

Below is some JS that re-sizes a font depending on the text length within a container.

Codepen with slightly modified code, but same idea as below:

function scaleFontSize(element) {
    var container = document.getElementById(element);

    // Reset font-size to 100% to begin
    container.style.fontSize = "100%";

    // Check if the text is wider than its container,
    // if so then reduce font-size
    if (container.scrollWidth > container.clientWidth) {
        container.style.fontSize = "70%";
    }
}

For me, I call this function when a user makes a selection in a drop-down, and then a div in my menu gets populated (this is where I have dynamic text occurring).

    scaleFontSize("my_container_div");

In addition, I also use CSS ellipses ("...") to truncate yet even longer text too, like so:

#my_container_div {
    width: 200px; /* width required for text-overflow to work */
    white-space: nowrap;
    overflow: hidden;
    text-overflow: ellipsis;
}

So, ultimately:

  • Short text: e.g. "APPLES"

    Fully rendered, nice big letters.

  • Long text: e.g. "APPLES & ORANGES"

    Gets scaled down 70%, via the above JS scaling function.

  • Super long text: e.g. "APPLES & ORANGES & BANAN..."

    Gets scaled down 70% AND gets truncated with a "..." ellipses, via the above JS scaling function together with the CSS rule.

You could also explore playing with CSS letter-spacing to make text narrower while keeping the same font size.

Creating SVG elements dynamically with javascript inside HTML

Add this to html:

<svg id="mySVG" xmlns="http://www.w3.org/2000/svg" xmlns:xlink="http://www.w3.org/1999/xlink"/>

Try this function and adapt for you program:

var svgNS = "http://www.w3.org/2000/svg";  

function createCircle()
{
    var myCircle = document.createElementNS(svgNS,"circle"); //to create a circle. for rectangle use "rectangle"
    myCircle.setAttributeNS(null,"id","mycircle");
    myCircle.setAttributeNS(null,"cx",100);
    myCircle.setAttributeNS(null,"cy",100);
    myCircle.setAttributeNS(null,"r",50);
    myCircle.setAttributeNS(null,"fill","black");
    myCircle.setAttributeNS(null,"stroke","none");

    document.getElementById("mySVG").appendChild(myCircle);
}     

Scroll to bottom of div with Vue.js

2021 easy solution that won't hurt your brain... use el.scrollIntoView()

Here is a fiddle.

This solution will not hurt your brain having to think about scrollTop or scrollHeight, has smooth scrolling built in, and even works in IE.

scrollIntoView() has options you can pass it like scrollIntoView({behavior: 'smooth'}) to get smooth scrolling.

methods: {
  scrollToElement() {
    const el = this.$el.getElementsByClassName('scroll-to-me')[0];

    if (el) {
      // Use el.scrollIntoView() to instantly scroll to the element
      el.scrollIntoView({behavior: 'smooth'});
    }
  }
}

Then if you wanted to scroll to this element on page load you could call this method like this:

mounted() {
  this.scrollToElement();
}

Else if you wanted to scroll to it on a button click or some other action you could call it the same way:

<button @click="scrollToElement">scroll to me</button>

The scroll works all the way down to IE 8. The smooth scroll effect does not work out of the box in IE or Safari. If needed there is a polyfill available for this here as @mostafaznv mentioned in the comments.

How to make MySQL table primary key auto increment with some prefix

I know it is late but I just want to share on what I have done for this. I'm not allowed to add another table or trigger so I need to generate it in a single query upon insert. For your case, can you try this query.

CREATE TABLE YOURTABLE(
IDNUMBER VARCHAR(7) NOT NULL PRIMARY KEY,
ENAME VARCHAR(30) not null
);

Perform a select and use this select query and save to the parameter @IDNUMBER

(SELECT IFNULL
     (CONCAT('LHPL',LPAD(
       (SUBSTRING_INDEX
        (MAX(`IDNUMBER`), 'LHPL',-1) + 1), 5, '0')), 'LHPL001')
    AS 'IDNUMBER' FROM YOURTABLE ORDER BY `IDNUMBER` ASC)

And then Insert query will be :

INSERT INTO YOURTABLE(IDNUMBER, ENAME) VALUES 
(@IDNUMBER, 'EMPLOYEE NAME');

The result will be the same as the other answer but the difference is, you will not need to create another table or trigger. I hope that I can help someone that have a same case as mine.

Java finished with non-zero exit value 2 - Android Gradle

Possible problem: You have exceeded dex 65k methods limit, may be you added some library or several methods before problem occurred?

Sort a single String in Java

Convert to array of chars ? Sort ? Convert back to String:

String s = "edcba";
char[] c = s.toCharArray();        // convert to array of chars 
java.util.Arrays.sort(c);          // sort
String newString = new String(c);  // convert back to String
System.out.println(newString);     // "abcde"

Floating point exception

It's caused by n % x, when x is 0. You should have x start at 2 instead. You should not use floating point here at all, since you only need integer operations.

General notes:

  1. Try to format your code better. Focus on using a consistent style. E.g. you have one else that starts immediately after a if brace (not even a space), and another with a newline in between.
  2. Don't use globals unless necessary. There is no reason for q to be global.
  3. Don't return without a value in a non-void (int) function.

Convert an integer to a byte array

What's wrong with converting it to a string?

[]byte(fmt.Sprintf("%d", myint))

Remove everything after a certain character

If you also want to keep "?" and just remove everything after that particular character, you can do:

var str = "/Controller/Action?id=11112&value=4444",
    stripped = str.substring(0, str.indexOf('?') + '?'.length);

// output: /Controller/Action?

Make Iframe to fit 100% of container's remaining height

you cant set the iframe height in % because your parent body height is not 100% so make the parent height as 100% and then apply iframe height 100%

For eg.
<html>
<head>
<style>
html,body{height:100%}
</style> 
</head>
<body>
<iframe src="http://www.quasarinfosystem.com" height="100%" width="100%" ></iframe>
</body>
</html>

What is the difference between Session.Abandon() and Session.Clear()

this code works and dont throw any exception:

Session.Abandon();  
Session["tempKey1"] = "tempValue1";

It's because when the Abandon method is called, the current Session object is queued for deletion but is not actually deleted until all of the script commands on the current page have been processed. This means that you can access variables stored in the Session object on the same page as the call to the Abandon method but not in any subsequent Web pages.

For example, in the following script, the third line prints the value Mary. This is because the Session object is not destroyed until the server has finished processing the script.

<% 
  Session.Abandon  
  Session("MyName") = "Mary" 
  Reponse.Write(Session("MyName")) 
%>

If you access the variable MyName on a subsequent Web page, it is empty. This is because MyName was destroyed with the previous Session object when the page containing the previous example finished processing.

from MSDN Session.Abandon

Convert String[] to comma separated string in java

Android developers are probably looking for TextUtils.join

Android docs: http://developer.android.com/reference/android/text/TextUtils.html

Code:

String[] name = {"amit", "rahul", "surya"};
TextUtils.join(",",name)

Add a common Legend for combined ggplots

I suggest using cowplot. From their R vignette:

# load cowplot
library(cowplot)

# down-sampled diamonds data set
dsamp <- diamonds[sample(nrow(diamonds), 1000), ]

# Make three plots.
# We set left and right margins to 0 to remove unnecessary spacing in the
# final plot arrangement.
p1 <- qplot(carat, price, data=dsamp, colour=clarity) +
   theme(plot.margin = unit(c(6,0,6,0), "pt"))
p2 <- qplot(depth, price, data=dsamp, colour=clarity) +
   theme(plot.margin = unit(c(6,0,6,0), "pt")) + ylab("")
p3 <- qplot(color, price, data=dsamp, colour=clarity) +
   theme(plot.margin = unit(c(6,0,6,0), "pt")) + ylab("")

# arrange the three plots in a single row
prow <- plot_grid( p1 + theme(legend.position="none"),
           p2 + theme(legend.position="none"),
           p3 + theme(legend.position="none"),
           align = 'vh',
           labels = c("A", "B", "C"),
           hjust = -1,
           nrow = 1
           )

# extract the legend from one of the plots
# (clearly the whole thing only makes sense if all plots
# have the same legend, so we can arbitrarily pick one.)
legend_b <- get_legend(p1 + theme(legend.position="bottom"))

# add the legend underneath the row we made earlier. Give it 10% of the height
# of one plot (via rel_heights).
p <- plot_grid( prow, legend_b, ncol = 1, rel_heights = c(1, .2))
p

combined plots with legend at bottom

How to make Apache serve index.php instead of index.html?

PHP will work only on the .php file extension.

If you are on Apache you can also set, in your httpd.conf file, the extensions for PHP. You'll have to find the line:

AddType application/x-httpd-php .php .html
                                     ^^^^^

and add how many extensions, that should be read with the PHP interpreter, as you want.

How to set editor theme in IntelliJ Idea

For IntelliJ in Mac

View -> Quick Switch theme (^`)-> color schema

"unmappable character for encoding" warning in Java

If you use eclipse (Eclipse can put utf8 code for you even you write utf8 character. You will see normal utf8 character when you programming but background will be utf8 code) ;

  1. Select Project
  2. Right click and select Properties
  3. Select Resource on Resource Panel(Top of right menu which opened after 2.)
  4. You can see in Resource Panel, Text File Encoding, select other which you want

P.S : this will ok if you static value in code. For Example String test = "IIIIIiiiiiiççççç";

Get selected item value from Bootstrap DropDown with specific ID

Try this code

<input type="TextBox" ID="yearBox" border="0" disabled>

$('#yearSelected li').on('click', function(){
                $('#yearBox').val($(this).text());
            });



<a href="#" class="dropdown-toggle" data-toggle="dropdown"> <i class="fas fa-calendar-alt"></i> <span>Academic Years</span> <i class="fas fa-chevron-down"></i> </a>
          <ul class="dropdown-menu">
            <li>
              <ul class="menu" id="yearSelected">
                <li><a href="#">2014-2015</a></li>
                <li><a href="#">2015-2016</a></li>
                <li><a href="#">2016-2017</a></li>
                <li><a href="#">2017-2018</a></li>

              </ul>
            </li>
          </ul>

its work for me

Chrome Extension - Get DOM content

The terms "background page", "popup", "content script" are still confusing you; I strongly suggest a more in-depth look at the Google Chrome Extensions Documentation.

Regarding your question if content scripts or background pages are the way to go:

Content scripts: Definitely
Content scripts are the only component of an extension that has access to the web-page's DOM.

Background page / Popup: Maybe (probably max. 1 of the two)
You may need to have the content script pass the DOM content to either a background page or the popup for further processing.


Let me repeat that I strongly recommend a more careful study of the available documentation!
That said, here is a sample extension that retrieves the DOM content on StackOverflow pages and sends it to the background page, which in turn prints it in the console:

background.js:

// Regex-pattern to check URLs against. 
// It matches URLs like: http[s]://[...]stackoverflow.com[...]
var urlRegex = /^https?:\/\/(?:[^./?#]+\.)?stackoverflow\.com/;

// A function to use as callback
function doStuffWithDom(domContent) {
    console.log('I received the following DOM content:\n' + domContent);
}

// When the browser-action button is clicked...
chrome.browserAction.onClicked.addListener(function (tab) {
    // ...check the URL of the active tab against our pattern and...
    if (urlRegex.test(tab.url)) {
        // ...if it matches, send a message specifying a callback too
        chrome.tabs.sendMessage(tab.id, {text: 'report_back'}, doStuffWithDom);
    }
});

content.js:

// Listen for messages
chrome.runtime.onMessage.addListener(function (msg, sender, sendResponse) {
    // If the received message has the expected format...
    if (msg.text === 'report_back') {
        // Call the specified callback, passing
        // the web-page's DOM content as argument
        sendResponse(document.all[0].outerHTML);
    }
});

manifest.json:

{
  "manifest_version": 2,
  "name": "Test Extension",
  "version": "0.0",
  ...

  "background": {
    "persistent": false,
    "scripts": ["background.js"]
  },
  "content_scripts": [{
    "matches": ["*://*.stackoverflow.com/*"],
    "js": ["content.js"]
  }],
  "browser_action": {
    "default_title": "Test Extension"
  },

  "permissions": ["activeTab"]
}

Python Pandas iterate over rows and access column names

The item from iterrows() is not a Series, but a tuple of (index, Series), so you can unpack the tuple in the for loop like so:

for (idx, row) in df.iterrows():
    print(row.loc['A'])
    print(row.A)
    print(row.index)

#0.890618586836
#0.890618586836
#Index(['A', 'B', 'C', 'D'], dtype='object')

How to update record using Entity Framework Core?

According to Microsoft docs:

the read-first approach requires an extra database read, and can result in more complex code for handling concurrency conflict

However, you should know that using Update method on DbContext will mark all the fields as modified and will include all of them in the query. If you want to update a subset of fields you should use the Attach method and then mark the desired field as modified manually.

context.Attach(person);
context.Entry(person).Property(p => p.Name).IsModified = true;
context.SaveChanges();

Change key pair for ec2 instance

Thanks for the tips guys. Will definitely keep them in mind when I need to rest the key pairs. However, in the interest of efficiency and laziness I've come up with something else:

  1. Create your new key pair and download the credentials
  2. Right-click your instance > Create AMI Once it is done
  3. terminate your instance (or just stop it until you are sure you can create another one from your new shiny AMI)
  4. Start a new EC2 instance from the AMI you just created and specify your new key pair created in step (1) above.

Hope this can be of use to you and save you some time as well as minimize the amount of white hair you get from stuff like this :)

Finding the average of an array using JS

You calculate an average by adding all the elements and then dividing by the number of elements.

var total = 0;
for(var i = 0; i < grades.length; i++) {
    total += grades[i];
}
var avg = total / grades.length;

The reason you got 68 as your result is because in your loop, you keep overwriting your average, so the final value will be the result of your last calculation. And your division and multiplication by grades.length cancel each other out.

Are email addresses case sensitive?

IETF Open Standards RFC 5321 2.4. General Syntax Principles and Transaction Model

SMTP implementations MUST take care to preserve the case of mailbox local-parts. In particular, for some hosts, the user "smith" is different from the user "Smith".

Mailbox domains follow normal DNS rules and are hence not case sensitive

How do I simulate a low bandwidth, high latency environment?

Charles

I came across Charles the web debugging proxy application and had great success in emulating network latency. It works on Windows, Mac, and Linux.

Charles on Mac

Bandwidth throttle / Bandwidth simulator

Charles can be used to adjust the bandwidth and latency of your Internet connection. This enables you to simulate modem conditions using your high-speed connection.

The bandwidth may be throttled to any arbitrary bytes per second. This enables any connection speed to be simulated.

The latency may also be set to any arbitrary number of milliseconds. The latency delay simulates the latency experienced on slower connections, that is the delay between making a request and the request being received at the other end.

DummyNet

You could also use vmware to run BSD or Linux and try this article (DummyNet) or this one.

Disabling Warnings generated via _CRT_SECURE_NO_DEPRECATE

i work on a multi platform project, so i can't use _s function and i don't want pollute my code with visual studio specific code.
my solution is disable the warning 4996 on the visual studio project. go to Project -> Properties -> Configuration properties -> C/C++ -> Advanced -> Disable specific warning add the value 4996.
if you use also the mfc and/or atl library (not my case) define before include mfc _AFX_SECURE_NO_DEPRECATE and before include atl _ATL_SECURE_NO_DEPRECATE.
i use this solution across visual studio 2003 and 2005.

p.s. if you use only visual studio the secure template overloads could be a good solution.

Command not found error in Bash variable assignment

In the interactive mode everything looks fine:

$ str="Hello World"
$ echo $str
Hello World

Obviously(!) as Johannes said, no space around =. In case there is any space around = then in the interactive mode it gives errors as

No command 'str' found

How to add header row to a pandas DataFrame

To fix your code you can simply change [Cov] to Cov.values, the first parameter of pd.DataFrame will become a multi-dimensional numpy array:

Cov = pd.read_csv("path/to/file.txt", sep='\t')
Frame=pd.DataFrame(Cov.values, columns = ["Sequence", "Start", "End", "Coverage"])
Frame.to_csv("path/to/file.txt", sep='\t')

But the smartest solution still is use pd.read_excel with header=None and names=columns_list.

How to enable LogCat/Console in Eclipse for Android?

In Eclipse, Goto Window-> Show View -> Other -> Android-> Logcat.

Logcat is nothing but a console of your Emulator or Device.

System.out.println does not work in Android. So you have to handle every thing in Logcat. More Info Look out this Documentation.

Edit 1: System.out.println is working on Logcat. If you use that the Tag will be like System.out and Message will be your message.

Multiple Buttons' OnClickListener() android

You could set the property:

android:onClick="buttonClicked"

in the xml file for each of those buttons, and use this in the java code:

public void buttonClicked(View view) {

    if (view.getId() == R.id.button1) {
        // button1 action
    } else if (view.getId() == R.id.button2) {
        //button2 action
    } else if (view.getId() == R.id.button3) {
        //button3 action
    }

}

How to replace DOM element in place using Javascript?

by using replaceChild():

<html>
<head>
</head>
<body>
  <div>
    <a id="myAnchor" href="http://www.stackoverflow.com">StackOverflow</a>
  </div>
<script type="text/JavaScript">
  var myAnchor = document.getElementById("myAnchor");
  var mySpan = document.createElement("span");
  mySpan.innerHTML = "replaced anchor!";
  myAnchor.parentNode.replaceChild(mySpan, myAnchor);
</script>
</body>
</html>

OpenSSL: PEM routines:PEM_read_bio:no start line:pem_lib.c:703:Expecting: TRUSTED CERTIFICATE

My situation was a little different. The solution was to strip the .pem from everything outside of the CERTIFICATE and PRIVATE KEY sections and to invert the order which they appeared. After converting from pfx to pem file, the certificate looked like this:

Bag Attributes
localKeyID: ...
issuer=...
-----BEGIN CERTIFICATE-----
...
-----END CERTIFICATE-----
Bag Attributes
more garbage...
-----BEGIN PRIVATE KEY-----
...
-----END PRIVATE KEY-----

After correcting the file, it was just:

-----BEGIN PRIVATE KEY-----
...
-----END PRIVATE KEY-----
-----BEGIN CERTIFICATE-----
...
-----END CERTIFICATE-----

Parse an URL in JavaScript

I wrote a javascript url parsing library, URL.js, you can use it for this.

Example:

url.parse("http://mysite.com/form_image_edit.php?img_id=33").get.img_id === "33"

How to use sed to remove the last n lines of a file

For deleting the last N lines of a file, you can use the same concept of

$ sed '2,4d' file

You can use a combo with tail command to reverse the file: if N is 5

$ tail -r file | sed '1,5d' file | tail -r > file

And this way runs also where head -n -5 file command doesn't run (like on a mac!).

Download files from SFTP with SSH.NET library

A simple working code to download a file with SSH.NET library is:

using (Stream fileStream = File.Create(@"C:\target\local\path\file.zip"))
{
    sftp.DownloadFile("/source/remote/path/file.zip", fileStream);
}

See also Downloading a directory using SSH.NET SFTP in C#.


To explain, why your code does not work:

The second parameter of SftpClient.DownloadFile is a stream to write a downloaded contents to.

You are passing in a read stream instead of a write stream. And moreover the path you are opening read stream with is a remote path, what cannot work with File class operating on local files only.

Just discard the File.OpenRead line and use a result of previous File.OpenWrite call instead (that you are not using at all now):

Stream file1 = File.OpenWrite(localFileName);

sftp.DownloadFile(file.FullName, file1);

Or even better, use File.Create to discard any previous contents that the local file may have.

I'm not sure if your localFileName is supposed to hold full path, or just file name. So you may need to add a path too, if necessary (combine localFileName with sDir?)

What svn command would list all the files modified on a branch?

This will list only modified files:

svn status -u | grep M

PHP array: count or sizeof?

I would use count() if they are the same, as in my experience it is more common, and therefore will cause less developers reading your code to say "sizeof(), what is that?" and having to consult the documentation.

I think it means sizeof() does not work like it does in C (calculating the size of a datatype). It probably made this mention explicitly because PHP is written in C, and provides a lot of identically named wrappers for C functions (strlen(), printf(), etc)

Current time formatting with Javascript

function startTime() {
    var today = new Date(),
        h = checkTime(((today.getHours() + 11) % 12 + 1)),
        m = checkTime(today.getMinutes()),
        s = checkTime(today.getSeconds());
    document.getElementById('demo').innerHTML = h + ":" + m + ":" + s;
    t = setTimeout(function () {
        startTime()
    }, 500);
}
startTime();

})();

05:12:00

String.Replace(char, char) method in C#

If you use

string temp = mystring.Replace("\r\n", "").Replace("\n", "");

then you won't have to worry about where your string is coming from.

Storing images in SQL Server?

While performance issues are valid the real reasons in practice that you should avoid storing images in a database are for database management reasons. Your database will grow very rapidly and databases cost much more than simple file storage. Database backups and restores are much more expensive and time-consuming than file backup restores. In a pinch, you can restore a smaller database much more quickly than one bloated with images. Compare 1 TB of file storage on Azure to a 1 TB database and you'll see the vast difference in cost.

How to create a multiline UITextfield?

Ok I did it with some trick ;) First build a UITextField and increased it's size like this :

CGRect frameRect = textField.frame;
        frameRect.size.height = 53;
        textField.frame = frameRect;

Then build a UITextView exactly in the same area that u made my UITextField, and deleted its background color. Now it looks like that u have a multiple lines TextField !

How to add an Android Studio project to GitHub

If you are using the latest version of Android studio. then you don't need to install additional software for Git other than GIT itself - https://git-scm.com/downloads

Steps

  1. Create an account on Github - https://github.com/join
  2. Install Git
  3. Open your working project in Android studio
  4. GoTo - File -> Settings -> Version Controll -> GitHub
  5. Enter Login and Password which you have created just on Git Account and click on test
  6. Once all credentials are true - it shows Success message. o.w Invalid Cred.
  7. Now click on VCS in android studio menu bar
  8. Select Import into Version Control -> Share Project on GitHub
  9. The popup dialog will occure contains all your files with check mark, do ok or commit all
  10. At next time whenever you want to push your project just click on VCS - > Commit Changes -> Commmit and Push.

That's it. You can find your project on your github now

Live video streaming using Java?

JMF was abandoned. VLC is more up to date and it reads everything. https://stackoverflow.com/a/5160010

I think vlc beats every other software out there yet, or at least the ones that I know...

Saving changes after table edit in SQL Server Management Studio

This is a risk to turning off this option. You can lose changes if you have change tracking turned on (your tables).

Chris

http://chrisbarba.wordpress.com/2009/04/15/sql-server-2008-cant-save-changes-to-tables/

How do I correctly upgrade angular 2 (npm) to the latest version?

UPDATE:
Starting from CLI v6 you can just run ng update in order to get your dependencies updated automatically to a new version.

With ng update sometimes you might want to add --force flag. If you do so make sure that the version of typescript you got installed this way is supported by your current angular version, otherwise you might need to downgrade the typescript version.

Also checkout this guide Updating your Angular projects


For bash users only

If you are on are on Mac/Linux or running bash on Windows(that wont work in default Windows CMD) you can run that oneliner:

npm install @angular/{animations,common,compiler,core,forms,http,platform-browser,platform-browser-dynamic,router,compiler-cli}@4.4.5 --save

yarn add @angular/{animations,common,compiler,core,forms,http,platform-browser,platform-browser-dynamic,router,compiler-cli}@4.4.5

Just specify version you wan't e.g @4.4.5 or put @latest to get the latest

Check your package.json just to make sure you are updating all @angular/* packages that you app is relying on

  • To see exact @angular version in your project run:
    npm ls @angular/compiler or yarn list @angular/compiler
  • To check the latest stable @angular version available on npm run:
    npm show @angular/compiler version

Is there a way to make numbers in an ordered list bold?

Another easy possibility would be to wrap the list item content into a <p>, style the <li> as bold and the <p> as regular. This would be also preferable from an IA point of view, especially when <li>s can contain sub-lists (to avoid mixing text nodes with block level elements).

Full example for your convenience:

<html>
    <head>
        <title>Ordered list items with bold numbers</title>
        <style>
            ol li {
                font-weight:bold;
            }
            li > p {
                font-weight:normal;
            }
        </style>
    </head>
    <body>
        <ol>
            <li>
                <p>List Item 1</p>
            </li>
            <li>
                <p>Liste Item 2</p>
                <ol>
                    <li>
                        <p>Sub List Item 1</p>
                     </li>
                    <li>
                        <p>Sub List Item 2</p>
                     </li>
                </ol>
            </li>
            <li>
                <p>List Item 3.</p>
            </li>
        </ol>
    </body>
</html>

If you prefer a more generic approach (that would also cover other scenarios like <li>s with descendants other than <p>, you might want to use li > * instead of li > p:

<html>
    <head>
        <title>Ordered list items with bold numbers</title>
        <style>
            ol li {
                font-weight:bold;
            }
            li > * {
                font-weight:normal;
            }
        </style>
    </head>
    <body>
        <ol>
            <li>
                <p>List Item 1</p>
            </li>
            <li>
                <p>Liste Item 2</p>
                <ol>
                    <li>
                        <p>Sub List Item 1</p>
                     </li>
                    <li>
                        <p>Sub List Item 2</p>
                     </li>
                </ol>
            </li>
            <li>
                <p>List Item 3.</p>
            </li>
            <li>
                <code>List Item 4.</code>
            </li>
        </ol>
    </body>
</html>

(Check the list item 4 here which is ol/li/code and not ol/li/p/code here.)

Just make sure to use the selector li > * and not li *, if you only want to style block level descendants as regular, but not also inlines like "foo <strong>bold word</strong> foo."

Is there a Java API that can create rich Word documents?

After a little more research, I came across iText, a PDF and RTF-file creation API. I think I can use the RTF generation to create a Doc-readable file that can then be edited using Doc and re-saved.

Anyone have any experience with iText, used in this fashion?

Python Timezone conversion

Python 3.9 adds the zoneinfo module so now only the the standard library is needed!

>>> from zoneinfo import ZoneInfo
>>> from datetime import datetime

>>> d = datetime(2020, 10, 31, 12, tzinfo=ZoneInfo('America/Los_Angeles'))
>>> d.astimezone(ZoneInfo('Europe/Berlin'))  # 12:00 in Cali will be 20:00 in Berlin
datetime.datetime(2020, 10, 31, 20, 0, tzinfo=zoneinfo.ZoneInfo(key='Europe/Berlin'))

Wikipedia list of available time zones


Some functions such as now() and utcnow() return timezone-unaware datetimes, meaning they contain no timezone information. I recommend only requesting timezone-aware values from them using the keyword tz=ZoneInfo('localtime').

If astimezone gets a timezone-unaware input, it will assume it is local time, which can lead to errors:

>>> datetime.utcnow()  # UTC -- NOT timezone-aware!!
datetime.datetime(2020, 6, 1, 22, 39, 57, 376479)
>>> datetime.now()     # Local time -- NOT timezone-aware!!
datetime.datetime(2020, 6, 2, 0, 39, 57, 376675)

>>> datetime.now(tz=ZoneInfo('localtime'))  # timezone-aware
datetime.datetime(2020, 6, 2, 0, 39, 57, 376806, tzinfo=zoneinfo.ZoneInfo(key='localtime'))
>>> datetime.now(tz=ZoneInfo('Europe/Berlin'))  # timezone-aware
datetime.datetime(2020, 6, 2, 0, 39, 57, 376937, tzinfo=zoneinfo.ZoneInfo(key='Europe/Berlin'))
>>> datetime.utcnow().astimezone(ZoneInfo('Europe/Berlin'))  # WRONG!!
datetime.datetime(2020, 6, 1, 22, 39, 57, 377562, tzinfo=zoneinfo.ZoneInfo(key='Europe/Berlin'))

Windows has no system time zone database, so here an extra package is needed:

pip install tzdata  

There is a backport to allow use in Python 3.6 to 3.8:

sudo pip install backports.zoneinfo

Then:

from backports.zoneinfo import ZoneInfo

How to disable JavaScript in Chrome Developer Tools?

Update August 2020

  1. Developer Tools (F12)
  2. Click the Gear icon

Settings

  1. Should open the Preference tab
  2. Disable Javascript option is on the far right

Disable JS option

Original answer

  1. Developer Tools (F12)
  2. Three vertical dots in upper right
  3. Settings
  4. Under the "Preferences" tab on the left

Preferences section

  1. There will be a "Debugger" section with the option (probably on far right)

Disable check box

Catch multiple exceptions in one line (except block)

From Python Documentation:

An except clause may name multiple exceptions as a parenthesized tuple, for example

except (IDontLikeYouException, YouAreBeingMeanException) as e:
    pass

Or, for Python 2 only:

except (IDontLikeYouException, YouAreBeingMeanException), e:
    pass

Separating the exception from the variable with a comma will still work in Python 2.6 and 2.7, but is now deprecated and does not work in Python 3; now you should be using as.

how to read xml file from url using php

$url = 'http://www.example.com'; $xml = simpleXML_load_file($url,"SimpleXMLElement",LIBXML_NOCDATA);

$url can be php file, as long as the file generate xml format data as output.

Copy/Paste from Excel to a web page

Excel 2007 has a feature for doing this under the "Data" tab that works pretty nicely.

How to run a cron job inside a docker container?

Try using clockwork gem to schedule tasks. Follow the steps provided in this link.

http://fuzzyblog.io/blog/rails/2017/05/11/adding-cron-to-a-dockerized-rails-application-using-clockwork.html

You can call the rake task inside lib/clock.rb file as below.

every(1.day, 'Import large data from csv files', :at => '5:00') do |job|
  `rake 'portal:import_data_from_csv'`
end

Create a separate container in docker-compose file & run the below command inside the container.

command: bundle exec clockwork lib/clock.rb

How to give color to each class in scatter plot in R?

Assuming the class variable is z, you can use:

with(df, plot(x, y, col = z))

however, it's important that z is a factor variable, as R internally stores factors as integers.

This way, 1 is 'black', 2 is 'red', 3 is 'green, ....

How to view the roles and permissions granted to any database user in Azure SQL server instance?

Building on @tmullaney 's answer, you can also left join in the sys.objects view to get insight when explicit permissions have been granted on objects. Make sure to use the LEFT join:

SELECT DISTINCT pr.principal_id, pr.name AS [UserName], pr.type_desc AS [User_or_Role], pr.authentication_type_desc AS [Auth_Type], pe.state_desc,
    pe.permission_name, pe.class_desc, o.[name] AS 'Object' 
    FROM sys.database_principals AS pr 
    JOIN sys.database_permissions AS pe ON pe.grantee_principal_id = pr.principal_id
    LEFT JOIN sys.objects AS o on (o.object_id = pe.major_id)

Linq UNION query to select two elements

EDIT:

Ok I found why the int.ToString() in LINQtoEF fails, please read this post: Problem with converting int to string in Linq to entities

This works on my side :

        List<string> materialTypes = (from u in result.Users
                                      select u.LastName)
                       .Union(from u in result.Users
                               select SqlFunctions.StringConvert((double) u.UserId)).ToList();

On yours it should be like this:

    IList<String> materialTypes = ((from tom in context.MaterialTypes
                                       where tom.IsActive == true
                                       select tom.Name)
                                       .Union(from tom in context.MaterialTypes
                                       where tom.IsActive == true
                                       select SqlFunctions.StringConvert((double)tom.ID))).ToList();

Thanks, i've learnt something today :)

regex with space and letters only?

Allowed only characters & spaces. Ex : Jayant Lonari

if (!/^[a-zA-Z\s]+$/.test(NAME)) {
    //Throw Error
}

Jenkins Git Plugin: How to build specific tag?

I set the Advanced->Refspec field to refs/tags/[your tag name]. This seems simpler than the various other suggestions for Refspec, but it worked just fine for me.

UPDATE 23/7/2014 - Actually, after further testing, it turns out this didn't work as expected. It appears that the HEAD version was still being checked out. Please undo this as the accepted answer. I ended up getting a working solution by following the post from gotgenes in this thread (30th March). The issue mentioned in that post of unnecessary triggering of builds was not an issue for me, as my job is triggered from an upstream job, not from polling SCM.

UPDATE APR-2018 - Note in the comments that this does work for one person, and agrees with Jenkins documentation.

Creating/writing into a new file in Qt

That is weird, everything looks fine, are you sure it does not work for you? Because this main surely works for me, so I would look somewhere else for the source of your problem.

#include <QFile>
#include <QTextStream>


int main()
{
    QString filename = "Data.txt";
    QFile file(filename);
    if (file.open(QIODevice::ReadWrite)) {
        QTextStream stream(&file);
        stream << "something" << endl;
    }
}

The code you provided is also almost the same as the one provided in detailed description of QTextStream so I am pretty sure, that the problem is elsewhere :)

Also note, that the file is not called Data but Data.txt and should be created/located in the directory from which the program was run (not necessarily the one where the executable is located).

WARNING: sanitizing unsafe style value url

I got the same issue while adding dynamic url in Image tag in Angular 7. I searched a lot and found this solution.

First, write below code in the component file.

constructor(private sanitizer: DomSanitizer) {}
public getSantizeUrl(url : string) {
    return this.sanitizer.bypassSecurityTrustUrl(url);
}

Now in your html image tag, you can write like this.

<img class="image-holder" [src]=getSantizeUrl(item.imageUrl) />

You can write as per your requirement instead of item.imageUrl

I got a reference from this site.dynamic urls. Hope this solution will help you :)

Android ListView Text Color

I needed to make a ListView with items of different colors. I modified Shardul's method a bit and result in this:

ArrayAdapter<String> adapter = new ArrayAdapter<String>(
                this, android.R.layout.simple_list_item_1, colorString) {
            @Override
            public View getView(int position, View convertView, ViewGroup parent) {
                TextView textView = (TextView) super.getView(position, convertView, parent);
                textView.setBackgroundColor(assignBackgroundColor(position));
                textView.setTextColor(assignTextColor(position));
                return textView;
            }
        };
        colorList.setAdapter(adapter);

assignBackgroundColor() and assignTextColor() are methods that assign color you want. They can be replaced with int[] arrays.

Convert/cast an stdClass object to another class

Yet another approach.

The following is now possible thanks to the recent PHP 7 version.

$theStdClass = (object) [
  'a' => 'Alpha',
  'b' => 'Bravo',
  'c' => 'Charlie',
  'd' => 'Delta',
];

$foo = new class($theStdClass)  {
  public function __construct($data) {
    if (!is_array($data)) {
      $data = (array) $data;
    }

    foreach ($data as $prop => $value) {
      $this->{$prop} = $value;
    }
  }
  public function word4Letter($letter) {
    return $this->{$letter};
  }
};

print $foo->word4Letter('a') . PHP_EOL; // Alpha
print $foo->word4Letter('b') . PHP_EOL; // Bravo
print $foo->word4Letter('c') . PHP_EOL; // Charlie
print $foo->word4Letter('d') . PHP_EOL; // Delta
print $foo->word4Letter('e') . PHP_EOL; // PHP Notice:  Undefined property

In this example, $foo is being initialized as an anonymous class that takes one array or stdClass as only parameter for the constructor.

Eventually, we loop through the each items contained in the passed object and dynamically assign then to an object's property.

To make this approch event more generic, you can write an interface or a Trait that you will implement in any class where you want to be able to cast an stdClass.

Extract the last substring from a cell

The answer provided by @Jean provides a working but obscure solution (although it doesn't handle trailing spaces)

As an alternative consider a vba user defined function (UDF)

Function RightWord(r As Range) As Variant
    Dim s As String
    s = Trim(r.Value)
    RightWord = Mid(s, InStrRev(s, " ") + 1)
End Function

Use in sheet as
=RightWord(A2)

formGroup expects a FormGroup instance

I was using reactive forms and ran into similar problems. What helped me was to make sure that I set up a corresponding FormGroup in the class. Something like this:

myFormGroup: FormGroup = this.builder.group({
    dob: ['', Validators.required]
});

Can anyone explain what JSONP is, in layman terms?

I have found a useful article that also explains the topic quite clearly and easy language. Link is JSONP

Some of the worth noting points are:

  1. JSONP pre-dates CORS.
  2. It is a pseudo-standard way to retreive data from a different domain,
  3. It has limited CORS features (only GET method)

Working is as follows:

  1. <script src="url?callback=function_name"> is included in the html code
  2. When step 1 gets executed it sens a function with the same function name (as given in the url parameter) as a response.
  3. If the function with the given name exists in the code, it will be executed with the data, if any, returned as an argument to that function.

jQuery if checkbox is checked

See main difference between ATTR | PROP | IS below:

Source: http://api.jquery.com/attr/

_x000D_
_x000D_
$( "input" )_x000D_
  .change(function() {_x000D_
    var $input = $( this );_x000D_
    $( "p" ).html( ".attr( 'checked' ): <b>" + $input.attr( "checked" ) + "</b><br>" +_x000D_
      ".prop( 'checked' ): <b>" + $input.prop( "checked" ) + "</b><br>" +_x000D_
      ".is( ':checked' ): <b>" + $input.is( ":checked" ) + "</b>" );_x000D_
  })_x000D_
  .change();
_x000D_
p {_x000D_
    margin: 20px 0 0;_x000D_
  }_x000D_
  b {_x000D_
    color: blue;_x000D_
  }
_x000D_
<meta charset="utf-8">_x000D_
  <title>attr demo</title>_x000D_
  <script src="https://code.jquery.com/jquery-1.10.2.js"></script>_x000D_
</head>_x000D_
<body>_x000D_
 _x000D_
<input id="check1" type="checkbox" checked="checked">_x000D_
<label for="check1">Check me</label>_x000D_
<p></p>_x000D_
 _x000D_
_x000D_
 _x000D_
</body>_x000D_
</html>
_x000D_
_x000D_
_x000D_

string.split - by multiple character delimiter

To show both string.Split and Regex usage:

string input = "abc][rfd][5][,][.";
string[] parts1 = input.Split(new string[] { "][" }, StringSplitOptions.None);
string[] parts2 = Regex.Split(input, @"\]\[");

Can I bind an array to an IN() condition?

Looking at PDO :Predefined Constants there is no PDO::PARAM_ARRAY which you would need as is listed on PDOStatement->bindParam

bool PDOStatement::bindParam ( mixed $parameter , mixed &$variable [, int $data_type [, int $length [, mixed $driver_options ]]] )

So I don't think it is achievable.

How do I find out my MySQL URL, host, port and username?

If you're already logged into the command line client try this:

mysql> select user();

It will output something similar to this:

+----------------+
| user()         |
+----------------+
| root@localhost |
+----------------+
1 row in set (0.41 sec)

In my example above, I was logged in as root from localhost.

To find port number and other interesting settings use this command:

mysql> show variables;

what is the difference between $_SERVER['REQUEST_URI'] and $_GET['q']?

Given this example url:

http://www.example.com/some-dir/yourpage.php?q=bogus&n=10

$_SERVER['REQUEST_URI'] will give you:

/some-dir/yourpage.php?q=bogus&n=10

Whereas $_GET['q'] will give you:

bogus

In other words, $_SERVER['REQUEST_URI'] will hold the full request path including the querystring. And $_GET['q'] will give you the value of parameter q in the querystring.

How do I get the total number of unique pairs of a set in the database?

What you're looking for is n choose k. Basically:

enter image description here

For every pair of 100 items, you'd have 4,950 combinations - provided order doesn't matter (AB and BA are considered a single combination) and you don't want to repeat (AA is not a valid pair).

Mockito : how to verify method was called on an object created within a method?

Yes, if you really want / need to do it you can use PowerMock. This should be considered a last resort. With PowerMock you can cause it to return a mock from the call to the constructor. Then do the verify on the mock. That said, csturtz's is the "right" answer.

Here is the link to Mock construction of new objects

How to use router.navigateByUrl and router.navigate in Angular

router.navigate vs router.navigateByUrl

router.navigate is just a convenience method that wraps router.navigateByUrl, it boils down to:

navigate(commands: any[], extras) {
    return router.navigateByUrl(router.createUrlTree(commands, extras), extras);
}

As mentioned in other answers router.navigateByUrl will only accept absolute URLs:

// This will work
router.navigateByUrl("http://localhost/team/33/user/11")
// This WON'T work even though relativeTo parameter is in the signature
router.navigateByUrl("../22", {relativeTo: route})

All the relative calculations are done by router.createUrlTree and router.navigate. Array syntax is used to treat every array element as a URL modifying "command". E.g. ".." - go up, "path" - go down, {expand: true} - add query param, etc.. You can use it like this:

// create /team/33/user/11
router.navigate(['/team', 33, 'user', 11]);

// assuming the current url is `/team/33/user/11` and the route points to `user/11`

// navigate to /team/33/user/11/details
router.navigate(['details'], {relativeTo: route});

// navigate to /team/33/user/22
router.navigate(['../22'], {relativeTo: route});

// navigate to /team/44/user/22
router.navigate(['../../team/44/user/22'], {relativeTo: route});

That {relativeTo: route} parameter is important as that's what router will use as the root for relative operations.

Get it through your component's constructor:

  // In my-awesome.component.ts:

  constructor(private route: ActivatedRoute, private router: Router) {}
  
  // Example call
  onNavigateClick() {
    // Navigates to a parent component
    this.router.navigate([..], { relativeTo: this.route })
  }

routerLink directive

Nicest thing about this directive is that it will retrieve the ActivatedRoute for you. Under the hood it's using already familiar:

router.navigateByUrl(router.createUrlTree(commands, { relativeTo: route }), { relativeTo: route });

Following variants will produce identical result:

[routerLink]="['../..']"

// if the string parameter is passed it will be wrapped into an array
routerLink="../.."

How to use XPath in Python?

If you are going to need it for html:

import lxml.html as html
root  = html.fromstring(string)
root.xpath('//meta')

Docker-Compose persistent data MySQL

Adding on to the answer from @Ohmen, you could also add an external flag to create the data volume outside of docker compose. This way docker compose would not attempt to create it. Also you wouldn't have to worry about losing the data inside the data-volume in the event of $ docker-compose down -v. The below example is from the official page.

version: "3.8"

services:
  db:
    image: postgres
    volumes:
      - data:/var/lib/postgresql/data

volumes:
  data:
    external: true

"Eliminate render-blocking CSS in above-the-fold content"

Hi For jQuery You can only use like this

Use async and type="text/javascript" only

Failed to resolve: com.google.firebase:firebase-core:16.0.1

If you use Firebase in a library module, you need to apply the google play services gradle plugin to it in addition to the app(s) module(s), but also, you need to beware of version 4.2.0 (and 4.1.0) which are broken, and use version 4.0.2 instead.

Here's the issue: https://github.com/google/play-services-plugins/issues/22

What is the use of static variable in C#? When to use it? Why can't I declare the static variable inside method?

A static variable shares the value of it among all instances of the class.

Example without declaring it static:

public class Variable
{
    public int i = 5;
    public void test()
    {
        i = i + 5;
        Console.WriteLine(i);
    }
}


public class Exercise
{
    static void Main()
    {
        Variable var = new Variable();
        var.test();
        Variable var1 = new Variable();
        var1.test();
        Console.ReadKey();
    }
}

Explanation: If you look at the above example, I just declare the int variable. When I run this code the output will be 10 and 10. Its simple.

Now let's look at the static variable here; I am declaring the variable as a static.

Example with static variable:

public class Variable
{
    public static int i = 5;
    public void test()
    {
        i = i + 5;
        Console.WriteLine(i);
    }
}


public class Exercise
{
    static void Main()
    {
        Variable var = new Variable();
        var.test();
        Variable var1 = new Variable();
        var1.test();
        Console.ReadKey();
    }
}

Now when I run above code, the output will be 10 and 15. So the static variable value is shared among all instances of that class.

Dynamically converting java object of Object class to a given class when class name is known

You don't have to convert the object to a MyClass object because it already is. Wnat you really want to do is to cast it, but since the class name is not known at compile time, you can't do that, since you can't declare a variable of that class. My guess is that you want/need something like "duck typing", i.e. you don't know the class name but you know the method name at compile time. Interfaces, as proposed by Gregory, are your best bet to do that.

C++: Where to initialize variables in constructor

There are many other reasons. You should always initialize all member variables in the initialization list if possible.

http://www.parashift.com/c++-faq-lite/ctors.html#faq-10.6

Can I export a variable to the environment from a bash script without sourcing it?

Another workaround that, depends on the case, it could be useful: creating another bash that inherites the exported variable. It is a particular case of @Keith Thompson answer, will all of those drawbacks.

export.bash:

# !/bin/bash
export VAR="HELLO, VARIABLE"
bash

Now:

./export.bash
echo $VAR

Why doesn't Python have multiline comments?

There should only be one way to do a thing, is contradicted by the usage of multiline strings and single line strings or switch/case and if, different form of loops.

Multiline comments are a pretty common feature and lets face it the multiline string comment is a hack with negative sideffects! I have seen lots of code doing the multiline comment trick and even editors use it.

But I guess every language has its quirks where the devs insist on never fixing it. I know such quirks from the java side as well, which have been open since the late 90s, never to be fixed!

Angular 2 Show and Hide an element

There are two options depending what you want to achieve :

  1. You can use the hidden directive to show or hide an element

    <div [hidden]="!edited" class="alert alert-success box-msg" role="alert">
      <strong>List Saved!</strong> Your changes has been saved.
    </div>
    
  2. You can use the ngIf control directive to add or remove the element. This is different of the hidden directive because it does not show / hide the element, but it add / remove from the DOM. You can loose unsaved data of the element. It can be the better choice for an edit component that is cancelled.

    <div *ngIf="edited" class="alert alert-success box-msg" role="alert"> 
      <strong>List Saved!</strong> Your changes has been saved.
    </div>
    

For you problem of change after 3 seconds, it can be due to incompatibility with setTimeout. Did you include angular2-polyfills.js library in your page ?

Is there a job scheduler library for node.js?

node-crontab allows you to edit system cron jobs from node.js. Using this library will allow you to run programs even after your main process termintates. Disclaimer: I'm the developer.

Redirecting to a certain route based on condition

After some diving through some documentation and source code, I think I got it working. Perhaps this will be useful for someone else?

I added the following to my module configuration:

angular.module(...)
 .config( ['$routeProvider', function($routeProvider) {...}] )
 .run( function($rootScope, $location) {

    // register listener to watch route changes
    $rootScope.$on( "$routeChangeStart", function(event, next, current) {
      if ( $rootScope.loggedUser == null ) {
        // no logged user, we should be going to #login
        if ( next.templateUrl != "partials/login.html" ) {
          // not going to #login, we should redirect now
          $location.path( "/login" );
        }
      }         
    });
 })

The one thing that seems odd is that I had to test the partial name (login.html) because the "next" Route object did not have a url or something else. Maybe there's a better way?

Addressing localhost from a VirtualBox virtual machine

I need to run on localhost, not some weird IP.

1) From your Mac terminal, do iconfig -a to find your local IP address. It's probably the last one.

en7: flags=8863<UP,BROADCAST,SMART,RUNNING,SIMPLEX,MULTICAST> mtu 1500 options=10b<RXCSUM,TXCSUM,VLAN_HWTAGGING,AV> ether 38:c9:86:32:0e:69 inet6 fe80::ea:393e:a54f:635%en7 prefixlen 64 secured scopeid 0xe inet 10.1.5.60 netmask 0xfffffe00 broadcast 10.1.5.255 nd6 options=201<PERFORMNUD,DAD> media: autoselect (1000baseT <full-duplex,flow-control>) status: active

e.g. 10.1.5.60

2) boot up your windows image. start > type cmd to get a terminal

3) notepad c:\windows\system32\drivers\etc\hosts

4) add the following line 10.1.5.60 localhost

5) open IE, and the following url should hit the server running on your mac: http://localhost:3000/

Build not visible in itunes connect

In case you are adding build with deployment target >9, add these keys to info.plist in case you are using camera and photos: Privacy - Camera Usage Description and Privacy - Photo Library Usage Description with a valid description.

I had the same issue when I submitted with blank string for these keys.

Eclipse: The resource is not on the build path of a Java project

You can add the src folder to build path by:

  1. Select Java perspective.
  2. Right click on src folder.
  3. Select Build Path > Use a source folder.

And you are done. Hope this help.

EDIT: Refer to the Eclipse documentation

How can I get the source directory of a Bash script from within the script itself?

pwd can be used to find the current working directory, and dirname to find the directory of a particular file (command that was run, is $0, so dirname $0 should give you the directory of the current script).

However, dirname gives precisely the directory portion of the filename, which more likely than not is going to be relative to the current working directory. If your script needs to change directory for some reason, then the output from dirname becomes meaningless.

I suggest the following:

#!/bin/bash

reldir=`dirname $0`
cd $reldir
directory=`pwd`

echo "Directory is $directory"

This way, you get an absolute, rather than a relative directory.

Since the script will be run in a separate Bash instance, there isn't any need to restore the working directory afterwards, but if you do want to change back in your script for some reason, you can easily assign the value of pwd to a variable before you change directory, for future use.

Although just

cd `dirname $0`

solves the specific scenario in the question, I find having the absolute path to more more useful generally.

Is there a JavaScript function that can pad a string to get to a determined length?

my combination of aboves solutions added to my own, always evolving version :)

//in preperation for ES6
String.prototype.lpad || (String.prototype.lpad = function( length, charOptional )
{
    if (length <= this.length) return this;
    return ( new Array((length||0)+1).join(String(charOptional)||' ') + (this||'') ).slice( -(length||0) );
});


'abc'.lpad(5,'.') == '..abc'
String(5679).lpad(10,0) == '0000005679'
String().lpad(4,'-') == '----' // repeat string

How do you force a CIFS connection to unmount

I had a very similar problem with davfs. In the man page of umount.davfs, I found that the -f -l -n -r -v options are ignored by umount.davfs. To force-unmount my davfs mount, I had to use umount -i -f -l /media/davmount.

Difference between number and integer datatype in oracle dictionary views

Integer is only there for the sql standard ie deprecated by Oracle.

You should use Number instead.

Integers get stored as Number anyway by Oracle behind the scenes.

Most commonly when ints are stored for IDs and such they are defined with no params - so in theory you could look at the scale and precision columns of the metadata views to see of no decimal values can be stored - however 99% of the time this will not help.

As was commented above you could look for number(38,0) columns or similar (ie columns with no decimal points allowed) but this will only tell you which columns cannot take decimals, and not what columns were defined so that INTS can be stored.

Suggestion: do a data profile on the number columns. Something like this:

 select max( case when trunc(column_name,0)=column_name then 0 else 1 end ) as has_dec_vals
 from table_name

How to export iTerm2 Profiles

It isn't the most obvious workflow. You first have to click "Load preferences from a custom folder or URL". Select the folder you want them saved in; I keep an appsync folder in Dropbox for these sorts of things. Once you have selected the folder, you can click "Save settings to Folder". On a new machine / fresh install of your OS, you can now load these settings from the folder. At first I was sure that loading preferences would wipe out my previous settings, but it didn't.

How to make Scrollable Table with fixed headers using CSS

I can think of a cheeky way to do it, I don't think this will be the best option but it will work.

Create the header as a separate table then place the other in a div and set a max size, then allow the scroll to come in by using overflow.

_x000D_
_x000D_
table {_x000D_
  width: 500px;_x000D_
}_x000D_
_x000D_
.scroll {_x000D_
  max-height: 60px;_x000D_
  overflow: auto;_x000D_
}
_x000D_
<table border="1">_x000D_
  <tr>_x000D_
  <th>head1</th>_x000D_
  <th>head2</th>_x000D_
  <th>head3</th>_x000D_
  <th>head4</th>_x000D_
  </tr>_x000D_
</table>_x000D_
<div class="scroll">_x000D_
  <table>_x000D_
    <tr><td>Text Text</td><td>Text Text</td><td>Text Text</td><td>Text Text</td></tr>_x000D_
    <tr><td>Text Text</td><td>Text Text</td><td>Text Text</td><td>Text Text</td></tr>_x000D_
    <tr><td>Text Text</td><td>Text Text</td><td>Text Text</td><td>Text Text</td></tr>_x000D_
    <tr><td>Text Text</td><td>Text Text</td><td>Text Text</td><td>Text Text</td></tr>_x000D_
    <tr><td>Text Text</td><td>Text Text</td><td>Text Text</td><td>Text Text</td></tr>_x000D_
    <tr><td>Text Text</td><td>Text Text</td><td>Text Text</td><td>Text Text</td></tr>_x000D_
    <tr><td>More Text</td><td>More Text</td><td>More Text</td><td>More Text</td></tr>_x000D_
    <tr><td>Text Text</td><td>Text Text</td><td>Text Text</td><td>Text Text</td></tr>_x000D_
    <tr><td>Even More Text Text</td><td>Even More Text Text</td><td>Even More Text Text</td><td>Even More Text Text</td></tr>_x000D_
  </table>_x000D_
</div>
_x000D_
_x000D_
_x000D_

What should a JSON service return on failure / error

Yes, you should use HTTP status codes. And also preferably return error descriptions in a somewhat standardized JSON format, like Nottingham’s proposal, see apigility Error Reporting:

The payload of an API Problem has the following structure:

  • type: a URL to a document describing the error condition (optional, and "about:blank" is assumed if none is provided; should resolve to a human-readable document; Apigility always provides this).
  • title: a brief title for the error condition (required; and should be the same for every problem of the same type; Apigility always provides this).
  • status: the HTTP status code for the current request (optional; Apigility always provides this).
  • detail: error details specific to this request (optional; Apigility requires it for each problem).
  • instance: URI identifying the specific instance of this problem (optional; Apigility currently does not provide this).

css rotate a pseudo :after or :before content:""

.process-list:after{
    content: "\2191";
    position: absolute;
    top:50%;
    right:-8px;
    background-color: #ea1f41;
    width:35px;
    height: 35px;
    border:2px solid #ffffff;
    border-radius: 5px;
    color: #ffffff;
    z-index: 10000;
    -webkit-transform: rotate(50deg) translateY(-50%);
    -moz-transform: rotate(50deg) translateY(-50%);
    -ms-transform: rotate(50deg) translateY(-50%);
    -o-transform: rotate(50deg) translateY(-50%);
    transform: rotate(50deg) translateY(-50%);
}

you can check this code . i hope you will easily understand.

Java NIO: What does IOException: Broken pipe mean?

Broken pipe means you wrote to a connection that is already closed by the other end.

isConnected() does not detect this condition. Only a write does.

is it wise to always call SocketChannel.isConnected() before attempting a SocketChannel.write()

It is pointless. The socket itself is connected. You connected it. What may not be connected is the connection itself, and you can only determine that by trying it.

C++ convert from 1 char to string?

This solution will work regardless of the number of char variables you have:

char c1 = 'z';
char c2 = 'w';
std::string s1{c1};
std::string s12{c1, c2};

Sass and combined child selector

For that single rule you have, there isn't any shorter way to do it. The child combinator is the same in CSS and in Sass/SCSS and there's no alternative to it.

However, if you had multiple rules like this:

#foo > ul > li > ul > li > a:nth-child(3n+1) {
    color: red;
}

#foo > ul > li > ul > li > a:nth-child(3n+2) {
    color: green;
}

#foo > ul > li > ul > li > a:nth-child(3n+3) {
    color: blue;
}

You could condense them to one of the following:

/* Sass */
#foo > ul > li > ul > li
    > a:nth-child(3n+1)
        color: red
    > a:nth-child(3n+2)
        color: green
    > a:nth-child(3n+3)
        color: blue

/* SCSS */
#foo > ul > li > ul > li {
    > a:nth-child(3n+1) { color: red; }
    > a:nth-child(3n+2) { color: green; }
    > a:nth-child(3n+3) { color: blue; }
}

Android Studio - Failed to notify project evaluation listener error

org.gradle.configureondemand=false

add this code into your gradle.properties file, It will work well but you may receive other errors.

The ResourceConfig instance does not contain any root resource classes

I am getting this exception, because of a missing ResourseConfig in Web.xml.

Add:

<init-param>
    <param-name>com.sun.jersey.config.property.packages</param-name>
    <param-value>/* Name of Package where your service class exists */</param-value>
</init-param>

Service class means: class which contains services like: @Path("/orders")

JavaScript for handling Tab Key press

You need to use Regular Expression For Website URL it is

var urlPattern = /(http|ftp|https)://[\w-]+(.[\w-]+)+([\w.,@?^=%&:/~+#-]*[\w@?^=%&/~+#-])?/

Use this Expression as in example

var regex = new RegExp(urlPattern ); var t = 'www.google.com';
var res = t.match(regex /g);

For You have to pass your web page as string to this javascript in variable t and get array

How to split CSV files as per number of rows specified?

This should do it for you - all your files will end up called Part1-Part500.

#!/bin/bash
FILENAME=10000.csv
HDR=$(head -1 $FILENAME)   # Pick up CSV header line to apply to each file
split -l 20 $FILENAME xyz  # Split the file into chunks of 20 lines each
n=1
for f in xyz*              # Go through all newly created chunks
do
   echo $HDR > Part${n}    # Write out header to new file called "Part(n)"
   cat $f >> Part${n}      # Add in the 20 lines from the "split" command
   rm $f                   # Remove temporary file
   ((n++))                 # Increment name of output part
done

How to construct a WebSocket URI relative to the page URI?

Here is my version which adds the tcp port in case it's not 80 or 443:

function url(s) {
    var l = window.location;
    return ((l.protocol === "https:") ? "wss://" : "ws://") + l.hostname + (((l.port != 80) && (l.port != 443)) ? ":" + l.port : "") + l.pathname + s;
}

Edit 1: Improved version as by suggestion of @kanaka :

function url(s) {
    var l = window.location;
    return ((l.protocol === "https:") ? "wss://" : "ws://") + l.host + l.pathname + s;
}

Edit 2: Nowadays I create the WebSocket this:

var s = new WebSocket(((window.location.protocol === "https:") ? "wss://" : "ws://") + window.location.host + "/ws");

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

What is stdClass in PHP?

stdClass is just a generic 'empty' class that's used when casting other types to objects. Despite what the other two answers say, stdClass is not the base class for objects in PHP. This can be demonstrated fairly easily:

class Foo{}
$foo = new Foo();
echo ($foo instanceof stdClass)?'Y':'N';
// outputs 'N'

I don't believe there's a concept of a base object in PHP

How to run functions in parallel?

This can be done elegantly with Ray, a system that allows you to easily parallelize and distribute your Python code.

To parallelize your example, you'd need to define your functions with the @ray.remote decorator, and then invoke them with .remote.

import ray

ray.init()

dir1 = 'C:\\folder1'
dir2 = 'C:\\folder2'
filename = 'test.txt'
addFiles = [25, 5, 15, 35, 45, 25, 5, 15, 35, 45]

# Define the functions. 
# You need to pass every global variable used by the function as an argument.
# This is needed because each remote function runs in a different process,
# and thus it does not have access to the global variables defined in 
# the current process.
@ray.remote
def func1(filename, addFiles, dir):
    # func1() code here...

@ray.remote
def func2(filename, addFiles, dir):
    # func2() code here...

# Start two tasks in the background and wait for them to finish.
ray.get([func1.remote(filename, addFiles, dir1), func2.remote(filename, addFiles, dir2)]) 

If you pass the same argument to both functions and the argument is large, a more efficient way to do this is using ray.put(). This avoids the large argument to be serialized twice and to create two memory copies of it:

largeData_id = ray.put(largeData)

ray.get([func1(largeData_id), func2(largeData_id)])

Important - If func1() and func2() return results, you need to rewrite the code as follows:

ret_id1 = func1.remote(filename, addFiles, dir1)
ret_id2 = func2.remote(filename, addFiles, dir2)
ret1, ret2 = ray.get([ret_id1, ret_id2])

There are a number of advantages of using Ray over the multiprocessing module. In particular, the same code will run on a single machine as well as on a cluster of machines. For more advantages of Ray see this related post.

Add a new column to existing table in a migration

laravel 5.6 and above

in case you want to add new column as a FOREIGN KEY to an existing table.

Create a new migration by executing this command : make:migration

Example :

php artisan make:migration add_store_id_to_users_table --table=users

In database/migrations folder you have new migration file, something like :

2018_08_08_093431_add_store_id_to_users_table.php (see the comments)

<?php

use Illuminate\Support\Facades\Schema;
use Illuminate\Database\Schema\Blueprint;
use Illuminate\Database\Migrations\Migration;

class AddStoreIdToUsersTable extends Migration
{
    /**
     * Run the migrations.
     *
     * @return void
     */
    public function up()
    {
        Schema::table('users', function (Blueprint $table) {

            // 1. Create new column
            // You probably want to make the new column nullable
            $table->integer('store_id')->unsigned()->nullable()->after('password');

            // 2. Create foreign key constraints
            $table->foreign('store_id')->references('id')->on('stores')->onDelete('SET NULL');
        });
    }

    /**
     * Reverse the migrations.
     *
     * @return void
     */
    public function down()
    {
        Schema::table('users', function (Blueprint $table) {

            // 1. Drop foreign key constraints
            $table->dropForeign(['store_id']);

            // 2. Drop the column
            $table->dropColumn('store_id');
        });
    }
}

After that run the command :

php artisan migrate

In case you want to undo the last migration for any reason, run this command :

php artisan migrate:rollback

You can find more information about migrations in the docs

How do I specify the JDK for a GlassFish domain?

Adding the actual content from dbf's link in order to keep the solution within stackoverflow.

It turns out that when I first installed Glassfish on my Windows system I had JDK 6 installed, and recently I had to downgrade to JDK 5 to compile some code for another project.

Apparently when Glassfish is installed it hard-codes its reference to your JDK location, so to fix this problem I ended up having to edit a file named asenv.bat. In short, I edited this file:

C:\glassfish\config\asenv.bat:

and I commented out the reference to JDK 6 and added a new reference to JDK 5, like this:

REM set AS_JAVA=C:\Program Files\Java\jdk1.6.0_04\jre/..
set AS_JAVA=C:\Program Files\Java\jdk1.5.0_16

Although the path doesn't appear to be case sensitive, I've spent hours debugging an issue around JMS Destination object not found due to my replacement path's case being incorrect.

How can I trigger a Bootstrap modal programmatically?

In order to manually show the modal pop up you have to do this

$('#myModal').modal('show');

You previously need to initialize it with show: false so it won't show until you manually do it.

$('#myModal').modal({ show: false})

Where myModal is the id of the modal container.

Read a text file in R line by line

Here is the solution with a for loop. Importantly, it takes the one call to readLines out of the for loop so that it is not improperly called again and again. Here it is:

fileName <- "up_down.txt"
conn <- file(fileName,open="r")
linn <-readLines(conn)
for (i in 1:length(linn)){
   print(linn[i])
}
close(conn)

Render Content Dynamically from an array map function in React Native

lapsList() {

    return this.state.laps.map((data) => {
      return (
        <View><Text>{data.time}</Text></View>
      )
    })
}

You forgot to return the map. this code will resolve the issue.

Spark dataframe: collect () vs select ()

Short answer in bolds:

  • collect is mainly to serialize
    (loss of parallelism preserving all other data characteristics of the dataframe)
    For example with a PrintWriter pw you can't do direct df.foreach( r => pw.write(r) ), must to use collect before foreach, df.collect.foreach(etc).
    PS: the "loss of parallelism" is not a "total loss" because after serialization it can be distributed again to executors.

  • select is mainly to select columns, similar to projection in relational algebra
    (only similar in framework's context because Spark select not deduplicate data).
    So, it is also a complement of filter in the framework's context.


Commenting explanations of other answers: I like the Jeff's classification of Spark operations in transformations (as select) and actions (as collect). It is also good remember that transforms (including select) are lazily evaluated.

assign value using linq

It can be done this way as well

foreach (Company company in listofCompany.Where(d => d.Id = 1)).ToList())
                {
                    //do your stuff here
                    company.Id= 2;
                    company.Name= "Sample"
                }

What is the difference between UTF-8 and Unicode?

Unicode is just a standard that defines a character set (UCS) and encodings (UTF) to encode this character set. But in general, Unicode is refered to the character set and not the standard.

Read The Absolute Minimum Every Software Developer Absolutely, Positively Must Know About Unicode and Character Sets (No Excuses!) and Unicode In 5 Minutes.

Efficient way to insert a number into a sorted array of numbers?

Simple (Demo):

function sortedIndex(array, value) {
    var low = 0,
        high = array.length;

    while (low < high) {
        var mid = (low + high) >>> 1;
        if (array[mid] < value) low = mid + 1;
        else high = mid;
    }
    return low;
}

SQL How to remove duplicates within select query?

here is the solution for your query returning only one row for each date in that table here in the solution 'tony' will occur twice as two different start dates are there for it

SELECT * FROM 
(
    SELECT T1.*, ROW_NUMBER() OVER(PARTITION BY TRUNC(START_DATE),OWNER_NAME ORDER BY 1,2 DESC )  RNM
    FROM TABLE T1
)
WHERE RNM=1

How to deal with http status codes other than 200 in Angular 2

Include required imports and you can make ur decision in handleError method Error status will give the error code

import { HttpClient, HttpErrorResponse } from '@angular/common/http';
import {Observable, throwError} from "rxjs/index";
import { catchError, retry } from 'rxjs/operators';
import {ApiResponse} from "../model/api.response";
import { TaxType } from '../model/taxtype.model'; 

private handleError(error: HttpErrorResponse) {
if (error.error instanceof ErrorEvent) {
  // A client-side or network error occurred. Handle it accordingly.
  console.error('An error occurred:', error.error.message);
} else {
  // The backend returned an unsuccessful response code.
  // The response body may contain clues as to what went wrong,
  console.error(
    `Backend returned code ${error.status}, ` +
    `body was: ${error.error}`);
}
// return an observable with a user-facing error message
return throwError(
  'Something bad happened; please try again later.');
  };

  getTaxTypes() : Observable<ApiResponse> {
return this.http.get<ApiResponse>(this.baseUrl).pipe(
  catchError(this.handleError)
);
  }

Write values in app.config file

For a .NET 4.0 console application, none of these worked for me. So I used the following below and it worked:

private static void UpdateSetting(string key, string value)
{
    Configuration configuration = ConfigurationManager.
        OpenExeConfiguration(Assembly.GetExecutingAssembly().Location);
    configuration.AppSettings.Settings[key].Value = value;
    configuration.Save();

    ConfigurationManager.RefreshSection("appSettings");
}

Nginx -- static file serving confusion with root & alias

alias is used to replace the location part path (LPP) in the request path, while the root is used to be prepended to the request path.

They are two ways to map the request path to the final file path.

alias could only be used in location block, and it will override the outside root.

alias and root cannot be used in location block together.

Similarity String Comparison in Java

Thank to the first answerer, I think there are 2 calculations of computeEditDistance(s1, s2). Due to high time spending of it, decided to improve the code's performance. So:

public class LevenshteinDistance {

public static int computeEditDistance(String s1, String s2) {
    s1 = s1.toLowerCase();
    s2 = s2.toLowerCase();

    int[] costs = new int[s2.length() + 1];
    for (int i = 0; i <= s1.length(); i++) {
        int lastValue = i;
        for (int j = 0; j <= s2.length(); j++) {
            if (i == 0) {
                costs[j] = j;
            } else {
                if (j > 0) {
                    int newValue = costs[j - 1];
                    if (s1.charAt(i - 1) != s2.charAt(j - 1)) {
                        newValue = Math.min(Math.min(newValue, lastValue),
                                costs[j]) + 1;
                    }
                    costs[j - 1] = lastValue;
                    lastValue = newValue;
                }
            }
        }
        if (i > 0) {
            costs[s2.length()] = lastValue;
        }
    }
    return costs[s2.length()];
}

public static void printDistance(String s1, String s2) {
    double similarityOfStrings = 0.0;
    int editDistance = 0;
    if (s1.length() < s2.length()) { // s1 should always be bigger
        String swap = s1;
        s1 = s2;
        s2 = swap;
    }
    int bigLen = s1.length();
    editDistance = computeEditDistance(s1, s2);
    if (bigLen == 0) {
        similarityOfStrings = 1.0; /* both strings are zero length */
    } else {
        similarityOfStrings = (bigLen - editDistance) / (double) bigLen;
    }
    //////////////////////////
    //System.out.println(s1 + "-->" + s2 + ": " +
      //      editDistance + " (" + similarityOfStrings + ")");
    System.out.println(editDistance + " (" + similarityOfStrings + ")");
}

public static void main(String[] args) {
    printDistance("", "");
    printDistance("1234567890", "1");
    printDistance("1234567890", "12");
    printDistance("1234567890", "123");
    printDistance("1234567890", "1234");
    printDistance("1234567890", "12345");
    printDistance("1234567890", "123456");
    printDistance("1234567890", "1234567");
    printDistance("1234567890", "12345678");
    printDistance("1234567890", "123456789");
    printDistance("1234567890", "1234567890");
    printDistance("1234567890", "1234567980");

    printDistance("47/2010", "472010");
    printDistance("47/2010", "472011");

    printDistance("47/2010", "AB.CDEF");
    printDistance("47/2010", "4B.CDEFG");
    printDistance("47/2010", "AB.CDEFG");

    printDistance("The quick fox jumped", "The fox jumped");
    printDistance("The quick fox jumped", "The fox");
    printDistance("The quick fox jumped",
            "The quick fox jumped off the balcany");
    printDistance("kitten", "sitting");
    printDistance("rosettacode", "raisethysword");
    printDistance(new StringBuilder("rosettacode").reverse().toString(),
            new StringBuilder("raisethysword").reverse().toString());
    for (int i = 1; i < args.length; i += 2) {
        printDistance(args[i - 1], args[i]);
    }


 }
}

How to tell if a string is not defined in a Bash shell script

another option: the "list array indices" expansion:

$ unset foo
$ foo=
$ echo ${!foo[*]}
0
$ foo=bar
$ echo ${!foo[*]}
0
$ foo=(bar baz)
$ echo ${!foo[*]}
0 1

the only time this expands to the empty string is when foo is unset, so you can check it with the string conditional:

$ unset foo
$ [[ ${!foo[*]} ]]; echo $?
1
$ foo=
$ [[ ${!foo[*]} ]]; echo $?
0
$ foo=bar
$ [[ ${!foo[*]} ]]; echo $?
0
$ foo=(bar baz)
$ [[ ${!foo[*]} ]]; echo $?
0

should be available in any bash version >= 3.0

Center align "span" text inside a div

If you know the width of the span you could just stuff in a left margin.

Try this:

.center { text-align: center}
div.center span { display: table; }

Add the "center: class to your .

If you want some spans centered, but not others, replace the "div.center span" in your style sheet to a class (e.g "center-span") and add that class to the span.

How to edit default dark theme for Visual Studio Code?

In Ubuntu I found the theme at /snap/code/55/usr/share/code/resources/app/extensions/theme-defaults/themes/dark_plus.json

How do I choose the URL for my Spring Boot webapp?

The server.contextPath or server.context-path works if

in pom.xml

  1. packing should be war not jar
  2. Add following dependencies

    <dependency>
        <groupId>org.springframework.boot</groupId>
         <artifactId>spring-boot-starter-web</artifactId>
    </dependency>
    <!-- Tomcat/TC server -->
     <dependency>
         <groupId>org.springframework.boot</groupId>
        <artifactId>spring-boot-starter-tomcat</artifactId>
        <scope>provided</scope>
     </dependency>
    

    In eclipse, right click on project --> Run as --> Spring Boot App.

get string value from HashMap depending on key name

If you will use Generics and define your map as

Map<String,String> map = new HashMap<String,String>();

then fetching value as

 String s = map.get("keyStr"); 

you wont be required to typecast the map.get() or call toString method to get String value

Check time difference in Javascript

Here is my rendition....

function get_time_difference(earlierDate, laterDate) 
{
    var oDiff = new Object();

    //  Calculate Differences
    //  -------------------------------------------------------------------  //
    var nTotalDiff = laterDate.getTime() - earlierDate.getTime();

    oDiff.days = Math.floor(nTotalDiff / 1000 / 60 / 60 / 24);
    nTotalDiff -= oDiff.days * 1000 * 60 * 60 * 24;

    oDiff.hours = Math.floor(nTotalDiff / 1000 / 60 / 60);
    nTotalDiff -= oDiff.hours * 1000 * 60 * 60;

    oDiff.minutes = Math.floor(nTotalDiff / 1000 / 60);
    nTotalDiff -= oDiff.minutes * 1000 * 60;

    oDiff.seconds = Math.floor(nTotalDiff / 1000);
    //  -------------------------------------------------------------------  //

    //  Format Duration
    //  -------------------------------------------------------------------  //
    //  Format Hours
    var hourtext = '00';
    if (oDiff.days > 0){ hourtext = String(oDiff.days);}
    if (hourtext.length == 1){hourtext = '0' + hourtext};

    //  Format Minutes
    var mintext = '00';
    if (oDiff.minutes > 0){ mintext = String(oDiff.minutes);}
    if (mintext.length == 1) { mintext = '0' + mintext };

    //  Format Seconds
    var sectext = '00';
    if (oDiff.seconds > 0) { sectext = String(oDiff.seconds); }
    if (sectext.length == 1) { sectext = '0' + sectext };

    //  Set Duration
    var sDuration = hourtext + ':' + mintext + ':' + sectext;
    oDiff.duration = sDuration;
    //  -------------------------------------------------------------------  //

    return oDiff;
}

What does axis in pandas mean?

The easiest way for me to understand is to talk about whether you are calculating a statistic for each column (axis = 0) or each row (axis = 1). If you calculate a statistic, say a mean, with axis = 0 you will get that statistic for each column. So if each observation is a row and each variable is in a column, you would get the mean of each variable. If you set axis = 1 then you will calculate your statistic for each row. In our example, you would get the mean for each observation across all of your variables (perhaps you want the average of related measures).

axis = 0: by column = column-wise = along the rows

axis = 1: by row = row-wise = along the columns

Disabled form fields not submitting data

As it was already mentioned: READONLY does not work for <input type='checkbox'> and <select>...</select>.

If you have a Form with disabled checkboxes / selects AND need them to be submitted, you can use jQuery:

$('form').submit(function(e) {
    $(':disabled').each(function(e) {
        $(this).removeAttr('disabled');
    })
});

This code removes the disabled attribute from all elements on submit.