Programs & Examples On #Ora 01438

ORA-01438: value larger than specified precision allowed for this column

ORA-01438: value larger than specified precision allows for this column

The error seems not to be one of a character field, but more of a numeric one. (If it were a string problem like WW mentioned, you'd get a 'value too big' or something similar.) Probably you are using more digits than are allowed, e.g. 1,000000001 in a column defined as number (10,2).

Look at the source code as WW mentioned to figure out what column may be causing the problem. Then check the data if possible that is being used there.

Is there a vr (vertical rule) in html?

HTML has little to no vertical positioning due to typographic nature of content layout. Vertical Rule just doesn't fit its semantics.

Using if(isset($_POST['submit'])) to not display echo when script is open is not working

You must give a name to your submit button

<input type="submit" value"Submit" name="login">

Then you can call the button with $_POST['login']

What are ABAP and SAP?

I have worked with SAP since 1998. SAP is a type of software called ERP (Enterprise Resource Planning) that large companies use to manage their day to day affairs. On the macro, the software can be split into two categories: Technical and Functional

Let's go Technical first, as it answers the "What is ABAP" part of your question.

Technical

There are two technical "stacks" within the SAP software, the first is the ABAP stack which is inclusive of all the original technology that SAP was. ABAP is the proprietary coding language for SAP to develop RICEFW objects (Reports, Interfaces, Conversions, Extensions, Forms and Workflows) within the ABAP stack.

The ABAP stack is traditionally navigated via Transaction Codes (T-Codes) to take you to different screens within the SAP Environment. From a technical perspective, you will do all of your performance and tuning of the WORK PROCESSES in the SAP system here, as well as configuring all of the system RFCs, building user profiles and also doing the necessary interfacing between the OS (usually Windows or HPUX) and the Oracle Database (currently Enterprise 11g).

The JAVA stack controls the "Netweaver" aspect of SAP which encapsulates SAP's ability to be accessed via the Internet via SAP Portal and it's ability to interface with other SAP and non-SAP legacy systems via Process Integration (PI).

SAP also has extensive capabilities in the Business Intelligence Field (BI) by accessing information stored within the Business Warehouse (BW). Currently, there is a new technology called HANA 1.0 that compresses the time to run reports against these repositories.

There are two primarily technologists that run ALL of these functions, they are called SAP Basis (Netweaver) Administrators and ABAP Developers.

Functional

SAP has specific pre-populated functional packages for different business areas. For example, Exxon runs the "IS Oil & Gas" package while Bank of America runs the "Banking" package, while further still Lockheed Martin runs the "Aerospace & Defense" package. These packages were developed over time by the amalgamation of intelligent functional customizations that could be intelligently ported to the system via inclusion in dot releases.

However, there are some vanilla functional modules that almost all entities run, regardless of their specific industry:

  • HR: Human Resources
  • PM: Project Management
  • FI: Financial
  • CO: Controllers
  • MM: Materials Management
  • SD: Sales and Distribution
  • PP: Production Planning

and finally the biggie:

  • MDM: Master Data Management which encapsulates the data for customer/vendor/material etc.

How to use JavaScript variables in jQuery selectors?

$("input").click(function(){
        var name = $(this).attr("name");
        $('input[name="' + name + '"]').hide();    
    });   

Also works with ID:

var id = $(this).attr("id");
$('input[id="' + id + '"]').hide();

when, (sometimes)

$('input#' + id).hide();

does not work, as it should.

You can even do both:

$('input[name="' + name + '"][id="' + id + '"]').hide();

html button to send email

You can use an anchor to attempt to open the user's default mail client, prepopulated, with mailto:, but you cannot send the actual email. *Apparently it is possible to do this with a form action as well, but browser support is varied and unreliable, so I do not suggest it.

HTML cannot send mail, you need to use a server side language like php, which is another topic. There are plently of good resources on how to do this here on SO or elsewhere on the internet.

If you are using php, I see SwiftMailer suggested quite a bit.

Better way to call javascript function in a tag

Modern browsers support a Content Security Policy or CSP. This is the highest level of web security and strongly recommended if you can apply it because it completely blocks all XSS attacks.

Both of your suggestions break with CSP enabled because they allow inline Javascript (which could be injected by a hacker) to execute in your page.

The best practice is to subscribe to the event in Javascript, as in Konrad Rudolph's answer.

What is the Git equivalent for revision number?

Along with the SHA-1 id of the commit, date and time of the server time would have helped?

Something like this:

commit happened at 11:30:25 on 19 aug 2013 would show as 6886bbb7be18e63fc4be68ba41917b48f02e09d7_19aug2013_113025

How to keep the header static, always on top while scrolling?

_x000D_
_x000D_
.header {_x000D_
  position: fixed;_x000D_
  top: 0;_x000D_
  left: 0;_x000D_
  width: 100%;_x000D_
  height: 88px;_x000D_
  z-index: 10;_x000D_
  background: #eeeeee;_x000D_
  -webkit-box-shadow: 0 7px 8px rgba(0, 0, 0, 0.12);_x000D_
  -moz-box-shadow: 0 7px 8px rgba(0, 0, 0, 0.12);_x000D_
  box-shadow: 0 7px 8px rgba(0, 0, 0, 0.12);_x000D_
}_x000D_
_x000D_
.header__content-text {_x000D_
  text-align: center;_x000D_
  padding: 15px 20px;_x000D_
}_x000D_
_x000D_
.page__content-container {_x000D_
  margin: 100px auto;_x000D_
  width: 975px;_x000D_
  padding: 30px;_x000D_
}
_x000D_
<div class="header">_x000D_
  <h1 class="header__content-text">_x000D_
    Header content will come here_x000D_
  </h1>_x000D_
</div>_x000D_
<div class="page__content-container">_x000D_
  <div style="height:600px;">_x000D_
    <a href="http://imgur.com/k9hz3">_x000D_
      <img src="http://i.imgur.com/k9hz3.jpg" title="Hosted by imgur.com" alt="" />_x000D_
    </a>_x000D_
  </div>_x000D_
  <div style="height:600px;">_x000D_
    <a href="http://imgur.com/TXuFQ">_x000D_
      <img src="http://i.imgur.com/TXuFQ.jpg" title="Hosted by imgur.com" alt="" />_x000D_
    </a>_x000D_
  </div>_x000D_
</div>
_x000D_
_x000D_
_x000D_

How to mute an html5 video player using jQuery

Are you using the default controls boolean attribute on the video tag? If so, I believe all the supporting browsers have mute buttons. If you need to wire it up, set .muted to true on the element in javascript (use .prop for jquery because it's an IDL attribute.) The speaker icon on the volume control is the mute button on chrome,ff, safari, and opera for example

Create a temporary table in a SELECT statement without a separate CREATE TABLE

Use this syntax:

CREATE TEMPORARY TABLE t1 (select * from t2);

Automatically creating directories with file output

The os.makedirs function does this. Try the following:

import os
import errno

filename = "/foo/bar/baz.txt"
if not os.path.exists(os.path.dirname(filename)):
    try:
        os.makedirs(os.path.dirname(filename))
    except OSError as exc: # Guard against race condition
        if exc.errno != errno.EEXIST:
            raise

with open(filename, "w") as f:
    f.write("FOOBAR")

The reason to add the try-except block is to handle the case when the directory was created between the os.path.exists and the os.makedirs calls, so that to protect us from race conditions.


In Python 3.2+, there is a more elegant way that avoids the race condition above:

import os

filename = "/foo/bar/baz.txt"
os.makedirs(os.path.dirname(filename), exist_ok=True)
with open(filename, "w") as f:
    f.write("FOOBAR")

How to increase time in web.config for executing sql query

I realise I'm a litle late to the game, but just spent over a day on trying to change the timeout of a webservice. It seemed to have a default timeout of 30 seconds. I after changing evry other timeout value I could find, including:

  • DB connection string Connect Timeout
  • httpRuntime executionTimeout
  • basicHttpBinding binding closeTimeout
  • basicHttpBinding binding sendTimeout
  • basicHttpBinding binding receiveTimeout
  • basicHttpBinding binding openTimeout

Finaley I found that it was the SqlCommand timeout that was defaulting to 30 seconds.

I decided to just duplicate the timeout of the connection string to the command. The connection string is configured in the web.config.

Some code:

namespace ROS.WebService.Common
{
  using System;
  using System.Configuration;
  using System.Data;
  using System.Data.SqlClient;

  public static class DataAccess
  {
    public static string ConnectionString { get; private set; }

    static DataAccess()
    {
      ConnectionString = ConfigurationManager.ConnectionStrings["ROSdb"].ConnectionString;
    }

    public static int ExecuteNonQuery(string cmdText, CommandType cmdType, params SqlParameter[] sqlParams)
    {
      using (SqlConnection conn = new SqlConnection(DataAccess.ConnectionString))
      {
        using (SqlCommand cmd = new SqlCommand(cmdText, conn) { CommandType = cmdType, CommandTimeout = conn.ConnectionTimeout })
        {
          foreach (var p in sqlParams) cmd.Parameters.Add(p);
          cmd.Connection.Open();
          return cmd.ExecuteNonQuery();
        }
      }
    }
  }
}

Change introduced to "duplicate" the timeout value from the connection string:CommandTimeout = conn.ConnectionTimeout

ReactJS Two components communicating

OK, there are few ways to do it, but I exclusively want focus on using store using Redux which makes your life much easier for these situations rather than give you a quick solution only for this case, using pure React will end up mess up in real big application and communicating between Components becomes harder and harder as the application grows...

So what Redux does for you?

Redux is like local storage in your application which can be used whenever you need data to be used in different places in your application...

Basically, Redux idea comes from flux originally, but with some fundamental changes including the concept of having one source of truth by creating only one store...

Look at the graph below to see some differences between Flux and Redux...

Redux and Flux

Consider applying Redux in your application from the start if your application needs communication between Components...

Also reading these words from Redux Documentation could be helpful to start with:

As the requirements for JavaScript single-page applications have become increasingly complicated, our code must manage more state than ever before. This state can include server responses and cached data, as well as locally created data that has not yet been persisted to the server. UI state is also increasing in complexity, as we need to manage active routes, selected tabs, spinners, pagination controls, and so on.

Managing this ever-changing state is hard. If a model can update another model, then a view can update a model, which updates another model, and this, in turn, might cause another view to update. At some point, you no longer understand what happens in your app as you have lost control over the when, why, and how of its state. When a system is opaque and non-deterministic, it's hard to reproduce bugs or add new features.

As if this wasn't bad enough, consider the new requirements becoming common in front-end product development. As developers, we are expected to handle optimistic updates, server-side rendering, fetching data before performing route transitions, and so on. We find ourselves trying to manage a complexity that we have never had to deal with before, and we inevitably ask the question: is it time to give up? The answer is no.

This complexity is difficult to handle as we're mixing two concepts that are very hard for the human mind to reason about: mutation and asynchronicity. I call them Mentos and Coke. Both can be great in separation, but together they create a mess. Libraries like React attempt to solve this problem in the view layer by removing both asynchrony and direct DOM manipulation. However, managing the state of your data is left up to you. This is where Redux enters.

Following in the steps of Flux, CQRS, and Event Sourcing, Redux attempts to make state mutations predictable by imposing certain restrictions on how and when updates can happen. These restrictions are reflected in the three principles of Redux.

How to use 'git pull' from the command line?

Try setting the HOME environment variable in Windows to your home folder (c:\users\username).

( you can confirm that this is the problem by doing echo $HOME in git bash and echo %HOME% in cmd - latter might not be available )

TSQL How do you output PRINT in a user defined function?

Use extended procedure xp_cmdshell to run a shell command. I used it to print output to a file:

exec xp_cmdshell 'echo "mytextoutput" >> c:\debuginfo.txt'

This creates the file debuginfo.txt if it does not exist. Then it adds the text "mytextoutput" (without quotation marks) to the file. Any call to the function will write an additional line.

You may need to enable this db-server property first (default = disabled), which I realize may not be to the liking of dba's for production environments though.

Multiple inheritance for an anonymous class

Anonymous classes must extend or implement something, like any other Java class, even if it's just java.lang.Object.

For example:

Runnable r = new Runnable() {
   public void run() { ... }
};

Here, r is an object of an anonymous class which implements Runnable.

An anonymous class can extend another class using the same syntax:

SomeClass x = new SomeClass() {
   ...
};

What you can't do is implement more than one interface. You need a named class to do that. Neither an anonymous inner class, nor a named class, however, can extend more than one class.

Creating a batch file, for simple javac and java command execution

  1. Open Notepad

  2. Type in the following:

    javac *
    java Main
    
  3. SaveAs Main.bat or whatever name you wish to use for the batch file

Make sure that Main.java is in the same folder along with your batch file

Double Click on the batch file to run the Main.java file

How to check if object has any properties in JavaScript?

How about this?

var obj = {},
var isEmpty = !obj;
var hasContent = !!obj

List of Stored Procedures/Functions Mysql Command Line

show procedure status

will show you the stored procedures.

show create procedure MY_PROC

will show you the definition of a procedure. And

help show

will show you all the available options for the show command.

Checking for Undefined In React

In case you also need to check if nextProps.blog is not undefined ; you can do that in a single if statement, like this:

if (typeof nextProps.blog !== "undefined" && typeof nextProps.blog.content !== "undefined") {
    //
}

And, when an undefined , empty or null value is not expected; you can make it more concise:

if (nextProps.blog && nextProps.blog.content) {
    //
}

IOS: verify if a point is inside a rect

Swift 4

let view = ...
let point = ...
view.bounds.contains(point)

Objective-C

Use CGRectContainsPoint():

bool CGRectContainsPoint(CGRect rect, CGPoint point);

Parameters

  • rect The rectangle to examine.
  • point The point to examine. Return Value true if the rectangle is not null or empty and the point is located within the rectangle; otherwise, false.

A point is considered inside the rectangle if its coordinates lie inside the rectangle or on the minimum X or minimum Y edge.

How to import Swagger APIs into Postman?

  • Click on the orange button ("choose files")
  • Browse to the Swagger doc (swagger.yaml)
  • After selecting the file, a new collection gets created in POSTMAN. It will contain folders based on your endpoints.

You can also get some sample swagger files online to verify this(if you have errors in your swagger doc).

jQuery datepicker, onSelect won't work

$('.date-picker').datepicker({
                    autoclose : true,
                    todayHighlight : true,
                    clearBtn: true,
                    format: 'yyyy-mm-dd', 
                    onSelect: function(value, date) { 
                         alert(123);
                    },
                    todayBtn: "linked",
                    startView: 0, maxViewMode: 0,minViewMode:0

                    }).on('changeDate',function(ev){
                    //this is right events ,trust me
                    }
});

How to create a hidden <img> in JavaScript?

Try setting the style to display=none:

<img src="a.gif" style="display:none">

Creating a thumbnail from an uploaded image

just in case you need to create thumb with a max width and a max height ...

function makeThumbnails($updir, $img, $id,$MaxWe=100,$MaxHe=150){
    $arr_image_details = getimagesize($img); 
    $width = $arr_image_details[0];
    $height = $arr_image_details[1];

    $percent = 100;
    if($width > $MaxWe) $percent = floor(($MaxWe * 100) / $width);

    if(floor(($height * $percent)/100)>$MaxHe)  
    $percent = (($MaxHe * 100) / $height);

    if($width > $height) {
        $newWidth=$MaxWe;
        $newHeight=round(($height*$percent)/100);
    }else{
        $newWidth=round(($width*$percent)/100);
        $newHeight=$MaxHe;
    }

    if ($arr_image_details[2] == 1) {
        $imgt = "ImageGIF";
        $imgcreatefrom = "ImageCreateFromGIF";
    }
    if ($arr_image_details[2] == 2) {
        $imgt = "ImageJPEG";
        $imgcreatefrom = "ImageCreateFromJPEG";
    }
    if ($arr_image_details[2] == 3) {
        $imgt = "ImagePNG";
        $imgcreatefrom = "ImageCreateFromPNG";
    }


    if ($imgt) {
        $old_image = $imgcreatefrom($img);
        $new_image = imagecreatetruecolor($newWidth, $newHeight);
        imagecopyresized($new_image, $old_image, 0, 0, 0, 0, $newWidth, $newHeight, $width, $height);

       $imgt($new_image, $updir."".$id."_t.jpg");
        return;    
    }
}

Clicking a checkbox with ng-click does not update the model

It is kind of a hack but wrapping it in a timeout seems to accomplish what you are looking for:

angular.module('myApp', [])
    .controller('Ctrl', ['$scope', '$timeout', function ($scope, $timeout) {
    $scope.todos = [{
        'text': "get milk",
        'done': true
    }, {
        'text': "get milk2",
            'done': false
    }];

    $scope.onCompleteTodo = function (todo) {
        $timeout(function(){
            console.log("onCompleteTodo -done: " + todo.done + " : " + todo.text);
            $scope.doneAfterClick = todo.done;
            $scope.todoText = todo.text;
        });
    };
}]);

PHP: Limit foreach() statement?

You can either use

break;

or

foreach() if ($tmp++ < 2) {
}

(the second solution is even worse)

Why use the INCLUDE clause when creating an index?

There is a limit to the total size of all columns inlined into the index definition. That said though, I have never had to create index that wide. To me, the bigger advantage is the fact that you can cover more queries with one index that has included columns as they don't have to be defined in any particular order. Think about is as an index within the index. One example would be the StoreID (where StoreID is low selectivity meaning that each store is associated with a lot of customers) and then customer demographics data (LastName, FirstName, DOB): If you just inline those columns in this order (StoreID, LastName, FirstName, DOB), you can only efficiently search for customers for which you know StoreID and LastName.

On the other hand, defining the index on StoreID and including LastName, FirstName, DOB columns would let you in essence do two seeks- index predicate on StoreID and then seek predicate on any of the included columns. This would let you cover all possible search permutationsas as long as it starts with StoreID.

Stopping a thread after a certain amount of time

If you want the threads to stop when your program exits (as implied by your example), then make them daemon threads.

If you want your threads to die on command, then you have to do it by hand. There are various methods, but all involve doing a check in your thread's loop to see if it's time to exit (see Nix's example).

Docker how to change repository name or rename image?

To rename an image, you give it a new tag, and then remove the old tag using the ‘rmi’ command:

$ docker tag $ docker rmi

This second step is scary, as ‘rmi’ means “remove image”. However, docker won’t actually remove the image if it has any other tags. That is, if you were to immediately follow this with: docker rmi , then it would actually remove the image (assuming there are no other tags assigned to the image)

What is the equivalent of Java static methods in Kotlin?

All static member and function should be inside companion block

  companion object {
    @JvmStatic
    fun main(args: Array<String>) {
    }

    fun staticMethod() {
    }
  }

VB.net Need Text Box to Only Accept Numbers

You can use the onkeydown Property of the TextBox for limiting its value to numbers only.

<asp:TextBox ID="TextBox1" runat="server" onkeydown = "return (!(event.keyCode>=65) && event.keyCode!=32);"></asp:TextBox>

!(keyCode>=65) check is for excludng Alphabets.

keyCode!=32 check is for excluding Space character inbetween the numbers.

If you want to exclude Symbols also from entering into the textbox, then include the below condition also in the 'onkeydown' property.

!(event.shiftKey && (event.keyCode >= 48 && event.keyCode <= 57))

Thus the TextBox will finally become

<asp:TextBox ID="TextBox1" runat="server" onkeydown = "return (!(event.keyCode>=65) && event.keyCode!=32 && !(event.shiftKey && (event.keyCode >= 48 && event.keyCode <= 57)));"></asp:TextBox>

Explanation:

KeyCode for 'a' is '65' and 'z' is '90'.

KeyCodes from '90' to '222' which are other symbols are also not needed.

KeyCode for 'Space' Key is '32' which is also not needed.

Then a combination of 'Shift' key and 'Number' keys (which denotes Symbols) also not needed. KeyCode for '0' is '48' and '9' is '57'.

Hence all these are included in the TextBox declaration itself which produces the desired result.

Try and see.

Overriding !important style

There we have another possibility to remove a property value from the CSS.

Like using the replace method in js. But you have to know exactly the ID of the style, or you can write a for loop to detecting that by (count styles on the page, then check if any of those 'includes' or 'match' an !important value. & you can count also - how much contains them, or just simply write a global [regexp: /str/gi] replacing method)

Mine is very simple, but I attach a jsBin, for example:

https://jsbin.com/geqodeg/edit?html,css,js,output

First I set the body background in CSS for yellow !important, then I overrided by JS for darkPink.

Python how to write to a binary file?

This is exactly what bytearray is for:

newFileByteArray = bytearray(newFileBytes)
newFile.write(newFileByteArray)

If you're using Python 3.x, you can use bytes instead (and probably ought to, as it signals your intention better). But in Python 2.x, that won't work, because bytes is just an alias for str. As usual, showing with the interactive interpreter is easier than explaining with text, so let me just do that.

Python 3.x:

>>> bytearray(newFileBytes)
bytearray(b'{\x03\xff\x00d')
>>> bytes(newFileBytes)
b'{\x03\xff\x00d'

Python 2.x:

>>> bytearray(newFileBytes)
bytearray(b'{\x03\xff\x00d')
>>> bytes(newFileBytes)
'[123, 3, 255, 0, 100]'

Get User's Current Location / Coordinates

Import library like:

import CoreLocation

set Delegate:

CLLocationManagerDelegate

Take variable like:

var locationManager:CLLocationManager!

On viewDidLoad() write this pretty code:

 locationManager = CLLocationManager()
    locationManager.delegate = self
    locationManager.desiredAccuracy = kCLLocationAccuracyBest
    locationManager.requestAlwaysAuthorization()

    if CLLocationManager.locationServicesEnabled(){
        locationManager.startUpdatingLocation()
    }

Write CLLocation delegate methods:

    //MARK: - location delegate methods
func locationManager(_ manager: CLLocationManager, didUpdateLocations locations: [CLLocation]) {
    let userLocation :CLLocation = locations[0] as CLLocation

    print("user latitude = \(userLocation.coordinate.latitude)")
    print("user longitude = \(userLocation.coordinate.longitude)")

    self.labelLat.text = "\(userLocation.coordinate.latitude)"
    self.labelLongi.text = "\(userLocation.coordinate.longitude)"

    let geocoder = CLGeocoder()
    geocoder.reverseGeocodeLocation(userLocation) { (placemarks, error) in
        if (error != nil){
            print("error in reverseGeocode")
        }
        let placemark = placemarks! as [CLPlacemark]
        if placemark.count>0{
            let placemark = placemarks![0]
            print(placemark.locality!)
            print(placemark.administrativeArea!)
            print(placemark.country!)

            self.labelAdd.text = "\(placemark.locality!), \(placemark.administrativeArea!), \(placemark.country!)"
        }
    }

}
func locationManager(_ manager: CLLocationManager, didFailWithError error: Error) {
    print("Error \(error)")
}

Now set permission for access the location, so add these key value into your info.plist file

 <key>NSLocationAlwaysUsageDescription</key>
<string>Will you allow this app to always know your location?</string>
<key>NSLocationWhenInUseUsageDescription</key>
<string>Do you allow this app to know your current location?</string>
<key>NSLocationAlwaysAndWhenInUseUsageDescription</key>
<string>Do you allow this app to know your current location?</string>

enter image description here

100% working without any issue. TESTED

How to exit git log or git diff

Actually, there are three ways to do it, precisely.

Type any of the following 3 commands.

  1. :q
  2. :z or
  3. Ctrl + z

P.S.: Sometimes, for someone, one of these options doesn't seem to work and for others it works.

Getting path relative to the current working directory?

public string MakeRelativePath(string workingDirectory, string fullPath)
{
    string result = string.Empty;
    int offset;

    // this is the easy case.  The file is inside of the working directory.
    if( fullPath.StartsWith(workingDirectory) )
    {
        return fullPath.Substring(workingDirectory.Length + 1);
    }

    // the hard case has to back out of the working directory
    string[] baseDirs = workingDirectory.Split(new char[] { ':', '\\', '/' });
    string[] fileDirs = fullPath.Split(new char[] { ':', '\\', '/' });

    // if we failed to split (empty strings?) or the drive letter does not match
    if( baseDirs.Length <= 0 || fileDirs.Length <= 0 || baseDirs[0] != fileDirs[0] )
    {
        // can't create a relative path between separate harddrives/partitions.
        return fullPath;
    }

    // skip all leading directories that match
    for (offset = 1; offset < baseDirs.Length; offset++)
    {
        if (baseDirs[offset] != fileDirs[offset])
            break;
    }

    // back out of the working directory
    for (int i = 0; i < (baseDirs.Length - offset); i++)
    {
        result += "..\\";
    }

    // step into the file path
    for (int i = offset; i < fileDirs.Length-1; i++)
    {
        result += fileDirs[i] + "\\";
    }

    // append the file
    result += fileDirs[fileDirs.Length - 1];

    return result;
}

This code is probably not bullet-proof but this is what I came up with. It's a little more robust. It takes two paths and returns path B as relative to path A.

example:

MakeRelativePath("c:\\dev\\foo\\bar", "c:\\dev\\junk\\readme.txt")
//returns: "..\\..\\junk\\readme.txt"

MakeRelativePath("c:\\dev\\foo\\bar", "c:\\dev\\foo\\bar\\docs\\readme.txt")
//returns: "docs\\readme.txt"

How to secure an ASP.NET Web API

Web API introduced an Attribute [Authorize] to provide security. This can be set globally (global.asx)

public static void Register(HttpConfiguration config)
{
    config.Filters.Add(new AuthorizeAttribute());
}

Or per controller:

[Authorize]
public class ValuesController : ApiController{
...

Of course your type of authentication may vary and you may want to perform your own authentication, when this occurs you may find useful inheriting from Authorizate Attribute and extending it to meet your requirements:

public class DemoAuthorizeAttribute : AuthorizeAttribute
{
    public override void OnAuthorization(System.Web.Http.Controllers.HttpActionContext actionContext)
    {
        if (Authorize(actionContext))
        {
            return;
        }
        HandleUnauthorizedRequest(actionContext);
    }

    protected override void HandleUnauthorizedRequest(System.Web.Http.Controllers.HttpActionContext actionContext)
    {
        var challengeMessage = new System.Net.Http.HttpResponseMessage(System.Net.HttpStatusCode.Unauthorized);
        challengeMessage.Headers.Add("WWW-Authenticate", "Basic");
        throw new HttpResponseException(challengeMessage);
    }

    private bool Authorize(System.Web.Http.Controllers.HttpActionContext actionContext)
    {
        try
        {
            var someCode = (from h in actionContext.Request.Headers where h.Key == "demo" select h.Value.First()).FirstOrDefault();
            return someCode == "myCode";
        }
        catch (Exception)
        {
            return false;
        }
    }
}

And in your controller:

[DemoAuthorize]
public class ValuesController : ApiController{

Here is a link on other custom implemenation for WebApi Authorizations:

http://www.piotrwalat.net/basic-http-authentication-in-asp-net-web-api-using-membership-provider/

How does one make random number between range for arc4random_uniform()?

I believe you should do

dice1 = arc4random_uniform(6) + 1;

to get the range 1 - 6. I don't do iOS objective C nor have I any knowledge on swift-language though. The random method should return a value between 0 and 5, and + 1 will make it a value between 1 and 6.

If you need a range between lets say 10 - 30 then just do

int random = arc4random_uniform(21) + 10;

What is the easiest way to remove all packages installed by pip?

In Command Shell of Windows, the command pip freeze | xargs pip uninstall -y won't work. So for those of you using Windows, I've figured out an alternative way to do so.

  1. Copy all the names of the installed packages of pip from the pip freeze command to a .txt file.
  2. Then, go the location of your .txt file and run the command pip uninstall -r *textfile.txt*

Are there any disadvantages to always using nvarchar(MAX)?

The job of the database is to store data so that it can be used by the enterprise. Part of making that data useful is ensuring that it is meaningful. Allowing someone to enter an unlimited number of characters for their first name isn't ensuring meaningful data.

Building these constraints into the business layer is a good idea, but that doesn't ensure that the database will remain intact. The only way to guarantee that the data rules are not violated is to enforce them at the lowest level possible in the database.

Using ChildActionOnly in MVC

You would use it if you are using RenderAction in any of your views, usually to render a partial view.

The reason for marking it with [ChildActionOnly] is that you need the controller method to be public so you can call it with RenderAction but you don't want someone to be able to navigate to a URL (e.g. /Controller/SomeChildAction) and see the results of that action directly.

Java SSLHandshakeException "no cipher suites in common"

It looks like you are trying to connect using TLSv1.2, which isn't widely implemented on servers. Does your destination support tls1.2?

Generating 8-character only UUIDs

This is a similar way I'm using here to generate an unique error code, based on Anton Purin answer, but relying on the more appropriate org.apache.commons.text.RandomStringGenerator instead of the (once, not anymore) deprecated org.apache.commons.lang3.RandomStringUtils:

@Singleton
@Component
public class ErrorCodeGenerator implements Supplier<String> {

    private RandomStringGenerator errorCodeGenerator;

    public ErrorCodeGenerator() {
        errorCodeGenerator = new RandomStringGenerator.Builder()
                .withinRange('0', 'z')
                .filteredBy(t -> t >= '0' && t <= '9', t -> t >= 'A' && t <= 'Z', t -> t >= 'a' && t <= 'z')
                .build();
    }

    @Override
    public String get() {
        return errorCodeGenerator.generate(8);
    }

}

All advices about collision still apply, please be aware of them.

Unable to instantiate default tuplizer [org.hibernate.tuple.entity.PojoEntityTuplizer]

I was getting the same error even after adding no-arg constructor,Then I figured out that I was missing several JARs.I am posting this so that if anyone gets the error like I got, make sure you have added these JARs in your lib folder :

activation-1.0.2.jar
antlr-2.7.6.jar
aopalliance.jar
asm-1.5.3.jar
asm-attrs-1.5.3.jar
cglib-2.1_3.jar
commons-beanutils-1.7.0.jar
commons-collections-2.1.1.jar
commons-digester-1.8.jar
commons-email-1.0.jar
commons-fileupload-1.1.1.jar
commons-io-1.1.jar
commons-lang-2.5.jar
commons-logging-1.1.3.jar
dom4j-1.6.1.jar
dumbster-1.6.jar
ehcache-1.2.3.jar
ejb3-persistence-3.3.1.jar
hibernate-commons-annotations-4.0.4.Final.jar
hibernate-core-4.2.8.Final.jar
icu4j-2.6.1.jar
javassist-3.4.GA.jar
javax.persistence_2.0.3.v201010191057.jar
javax.servlet.jsp.jstl-1.2.1.jar
jaxb-api-2.1.jar
jaxb-impl-2.1.3.jar
jaxen-1.1.1.jar
jboss-logging-3.1.3.GA.jar
jdom-1.0.jar
jstl-1.2.jar
jta-1.1.jar
lucene-core-2.3.2.jar
lucene-highlighter-2.0.0.jar
mail-1.4.jar
mysql-connector-java-5.0.8-bin.jar
org.springframework.orm.jar
slf4j-api-1.6.1.jar
slf4j-log4j12-1.5.6.jar
spring-aop-4.0.0.RELEASE.jar
spring-aspects-4.0.0.RELEASE-javadoc.jar
spring-beans-4.0.0.RELEASE.jar
spring-build-src-4.0.0.RELEASE.jar
spring-context-4.0.0.RELEASE.jar
spring-core-4.0.0.RELEASE.jar
spring-expression-4.0.0.RELEASE.jar
spring-framework-bom-4.0.0.RELEASE.jar
spring-jdbc-4.0.0.RELEASE.jar
spring-orm-4.0.0.RELEASE.jar
spring-tx-4.0.0.RELEASE.jar
spring-web-4.0.0.RELEASE.jar
spring-webmvc-4.0.0.RELEASE.jar
stax-api-1.0-2.jar
validation-api-1.0.0.GA.jar
xalan-2.6.0.jar
xercesImpl-2.6.2.jar
xml-apis-1.3.02.jar
xmlParserAPIs-2.6.2.jar
xom-1.0.jar

How to send a simple string between two programs using pipes?

A regular pipe can only connect two related processes. It is created by a process and will vanish when the last process closes it.

A named pipe, also called a FIFO for its behavior, can be used to connect two unrelated processes and exists independently of the processes; meaning it can exist even if no one is using it. A FIFO is created using the mkfifo() library function.

Example

writer.c

#include <fcntl.h>
#include <sys/stat.h>
#include <sys/types.h>
#include <unistd.h>

int main()
{
    int fd;
    char * myfifo = "/tmp/myfifo";

    /* create the FIFO (named pipe) */
    mkfifo(myfifo, 0666);

    /* write "Hi" to the FIFO */
    fd = open(myfifo, O_WRONLY);
    write(fd, "Hi", sizeof("Hi"));
    close(fd);

    /* remove the FIFO */
    unlink(myfifo);

    return 0;
}

reader.c

#include <fcntl.h>
#include <stdio.h>
#include <sys/stat.h>
#include <unistd.h>

#define MAX_BUF 1024

int main()
{
    int fd;
    char * myfifo = "/tmp/myfifo";
    char buf[MAX_BUF];

    /* open, read, and display the message from the FIFO */
    fd = open(myfifo, O_RDONLY);
    read(fd, buf, MAX_BUF);
    printf("Received: %s\n", buf);
    close(fd);

    return 0;
}

Note: Error checking was omitted from the above code for simplicity.

Calculating Distance between two Latitude and Longitude GeoCoordinates

When CPU/math computing power is limited:

There are times (such as in my work) when computing power is scarce (e.g. no floating point processor, working with small microcontrollers) where some trig functions can take an exorbitant amount of CPU time (e.g. 3000+ clock cycles), so when I only need an approximation, especially if if the CPU must not be tied up for a long time, I use this to minimize CPU overhead:

/**------------------------------------------------------------------------
 * \brief  Great Circle distance approximation in km over short distances.
 *
 * Can be off by as much as 10%.
 *
 * approx_distance_in_mi = sqrt(x * x + y * y)
 *
 * where x = 69.1 * (lat2 - lat1)
 * and y = 69.1 * (lon2 - lon1) * cos(lat1/57.3)
 *//*----------------------------------------------------------------------*/
double    ApproximateDisatanceBetweenTwoLatLonsInKm(
                  double lat1, double lon1,
                  double lat2, double lon2
                  ) {
    double  ldRadians, ldCosR, x, y;

    ldRadians = (lat1 / 57.3) * 0.017453292519943295769236907684886;
    ldCosR = cos(ldRadians);
    x = 69.1 * (lat2 - lat1);
    y = 69.1 * (lon2 - lon1) * ldCosR;

    return sqrt(x * x + y * y) * 1.609344;  /* Converts mi to km. */
}

Credit goes to https://github.com/kristianmandrup/geo_vectors/blob/master/Distance%20calc%20notes.txt.

Why declare unicode by string in python?

As others have said, # coding: specifies the encoding the source file is saved in. Here are some examples to illustrate this:

A file saved on disk as cp437 (my console encoding), but no encoding declared

b = 'über'
u = u'über'
print b,repr(b)
print u,repr(u)

Output:

  File "C:\ex.py", line 1
SyntaxError: Non-ASCII character '\x81' in file C:\ex.py on line 1, but no
encoding declared; see http://www.python.org/peps/pep-0263.html for details

Output of file with # coding: cp437 added:

über '\x81ber'
über u'\xfcber'

At first, Python didn't know the encoding and complained about the non-ASCII character. Once it knew the encoding, the byte string got the bytes that were actually on disk. For the Unicode string, Python read \x81, knew that in cp437 that was a ü, and decoded it into the Unicode codepoint for ü which is U+00FC. When the byte string was printed, Python sent the hex value 81 to the console directly. When the Unicode string was printed, Python correctly detected my console encoding as cp437 and translated Unicode ü to the cp437 value for ü.

Here's what happens with a file declared and saved in UTF-8:

++ber '\xc3\xbcber'
über u'\xfcber'

In UTF-8, ü is encoded as the hex bytes C3 BC, so the byte string contains those bytes, but the Unicode string is identical to the first example. Python read the two bytes and decoded it correctly. Python printed the byte string incorrectly, because it sent the two UTF-8 bytes representing ü directly to my cp437 console.

Here the file is declared cp437, but saved in UTF-8:

++ber '\xc3\xbcber'
++ber u'\u251c\u255dber'

The byte string still got the bytes on disk (UTF-8 hex bytes C3 BC), but interpreted them as two cp437 characters instead of a single UTF-8-encoded character. Those two characters where translated to Unicode code points, and everything prints incorrectly.

Facebook Android Generate Key Hash

Great blog post on the subject

Extracting the Key Hash from .p12 key

  1. Open Terminal or Command line and navigate to where your .p12 key is.
  2. Type in: “keytool -v -list -keystore mycert.p12 -storetype pkcs12" where mycert.p12 is the filename of your .p12 key.
  3. Enter keystore password (the one you used when exported .p12 key). 4 . Copy sha1 fingerprint signature bytes text.
  4. The bytes at sha1 fingerprint signature are needed to write the “sha1.bin” file. You can use a hexadecimal editor to paste the bytes you copied. Afterwards, save the file as “sha1.bin”.
  5. Open terminal again and type in: “openssl base64 -in sha1.bin -out base64.txt”.
  6. The resulting “base64.txt” will contain the Key Hash that is needed for Facebook.

Great and simple hexadecimal editor for mac: HexFiend

OpenSSL should be preinstalled on mac, and here is the link for Windows version.

Link

Can I add a custom attribute to an HTML tag?

Another approach, which is clean and will keep the document valid, is to concatenate the data you want into another tag e.g. id, then use split to take what you want when you want it.

<html>
<script>
  function demonstrate(){
    var x = document.getElementById("example data").querySelectorAll("input");
    console.log(x);
    for(i=0;i<x.length;i++){
      var line_to_illustrate = x[i].id  + ":" + document.getElementById ( x[i].id ).value;
      //concatenated values
      console.log("this is all together: " + line_to_illustrate); 
      //split values
      var split_line_to_illustrate = line_to_illustrate.split(":");
      for(j=0;j<split_line_to_illustrate.length;j++){
        console.log("item " + j+ " is: " + split_line_to_illustrate[j]);
      }      
    }
  }
</script> 

<body>

<div id="example data">
  <!-- consider the id values representing a 'from-to' relationship -->
  <input id="1:2" type="number" name="quantity" min="0" max="9" value="2">
  <input id="1:4" type="number" name="quantity" min="0" max="9" value="1">
  <input id="3:6" type="number" name="quantity" min="0" max="9" value="5">  
</div>

<input type="button" name="" id="?" value="show me" onclick="demonstrate()"/>

</body>
</html>

Add items in array angular 4

Yes there is a way to do it.

First declare a class.

//anyfile.ts
export class Custom
{
  name: string, 
  empoloyeeID: number
}

Then in your component import the class

import {Custom} from '../path/to/anyfile.ts'
.....
export class FormComponent implements OnInit {
 name: string;
 empoloyeeID : number;
 empList: Array<Custom> = [];
 constructor() {

 }

 ngOnInit() {
 }
 onEmpCreate(){
   //console.log(this.name,this.empoloyeeID);
   let customObj = new Custom();
   customObj.name = "something";
   customObj.employeeId = 12; 
   this.empList.push(customObj);
   this.name ="";
   this.empoloyeeID = 0; 
 }
}

Another way would be to interfaces read the documentation once - https://www.typescriptlang.org/docs/handbook/interfaces.html

Also checkout this question, it is very interesting - When to use Interface and Model in TypeScript / Angular2

Using Get-childitem to get a list of files modified in the last 3 days

Try this:

(Get-ChildItem -Path c:\pstbak\*.* -Filter *.pst | ? {
  $_.LastWriteTime -gt (Get-Date).AddDays(-3) 
}).Count

How to pass optional arguments to a method in C++?

Here is an example of passing mode as optional parameter

void myfunc(int blah, int mode = 0)
{
    if (mode == 0)
        do_something();
     else
        do_something_else();
}

you can call myfunc in both ways and both are valid

myfunc(10);     // Mode will be set to default 0
myfunc(10, 1);  // Mode will be set to 1

Unsupported operand type(s) for +: 'int' and 'str'

try,

str_list = " ".join([str(ele) for ele in numlist])

this statement will give you each element of your list in string format

print("The list now looks like [{0}]".format(str_list))

and,

change print(numlist.pop(2)+" has been removed") to

print("{0} has been removed".format(numlist.pop(2)))

as well.

PHP 5 disable strict standards error

Do you want to disable error reporting, or just prevent the user from seeing it? It’s usually a good idea to log errors, even on a production site.

# in your PHP code:
ini_set('display_errors', '0');     # don't show any errors...
error_reporting(E_ALL | E_STRICT);  # ...but do log them

They will be logged to your standard system log, or use the error_log directive to specify exactly where you want errors to go.

CSS: Truncate table cells, but fit as much as possible

Given that 'table-layout:fixed' is the essential layout requirement, that this creates evenly spaced non-adjustable columns, but that you need to make cells of different percentage widths, perhaps set the 'colspan' of your cells to a multiple?

For example, using a total width of 100 for easy percentage calculations, and saying that you need one cell of 80% and another of 20%, consider:

<TABLE width=100% style="table-layout:fixed;white-space:nowrap;overflow:hidden;">
     <tr>
          <td colspan=100>
               text across entire width of table
          </td>
     <tr>
          <td colspan=80>
               text in lefthand bigger cell
          </td>
          <td colspan=20>
               text in righthand smaller cell
          </td>
</TABLE>

Of course, for columns of 80% and 20%, you could just set the 100% width cell colspan to 5, the 80% to 4, and the 20% to 1.

How to select all the columns of a table except one column?

You can retrieve the list of column name by simple query and then remove those column by apply where query like this.

SELECT * FROM (
SELECT COLUMN_NAME
FROM INFORMATION_SCHEMA.COLUMNS
WHERE TABLE_NAME = N'TableName'
) AS allColumns
WHERE allColumns.COLUMN_NAME NOT IN ('unwantedCol1', 'unwantedCol2')

How can I toggle word wrap in Visual Studio?

I use this feature often enough that I add a custom button to the command bar.

  1. Click on the Add or Remove Buttons -> Customize
  2. Click on the Commands tab
  3. Click Add Command...
  4. Select Edit (or Edit|Advanced for newer VS versions) from the list
  5. Find Toggle Word Wrap and drag it onto your bar

Hidden Features of C#?

The C# ?? null coalescing operator -

Not really hidden, but rarely used. Probably because a lot of developers run a mile when they see the conditional ? operator, so they run two when they see this one. Used:

string mystring = foo ?? "foo was null"

rather than

string mystring;
if (foo==null)
    mystring = "foo was null";
else
    mystring = foo;

jQuery Remove string from string

pretty sure you just want the plain old replace function. use like this:

myString.replace('username1','');

i suppose if you want to remove the trailing comma do this instead:

myString.replace('username1,','');

edit:

here is your site specific code:

jQuery("#post_like_list-510").text().replace(...) 

Blur the edges of an image or background image with CSS

If what you're looking for is simply to blur the image edges you can simply use the box-shadow with an inset.

Working example: http://jsfiddle.net/d9Q5H/1/

Screenshot

HTML:

<div class="image-blurred-edge"></div>

CSS

.image-blurred-edge {
    background-image: url('http://lorempixel.com/200/200/city/9');
    width: 200px;
    height: 200px;
    /* you need to match the shadow color to your background or image border for the desired effect*/
    box-shadow: 0 0 8px 8px white inset;
}

How to use if-else logic in Java 8 stream forEach

Just put the condition into the lambda itself, e.g.

animalMap.entrySet().stream()
        .forEach(
                pair -> {
                    if (pair.getValue() != null) {
                        myMap.put(pair.getKey(), pair.getValue());
                    } else {
                        myList.add(pair.getKey());
                    }
                }
        );

Of course, this assumes that both collections (myMap and myList) are declared and initialized prior to the above piece of code.


Update: using Map.forEach makes the code shorter, plus more efficient and readable, as Jorn Vernee kindly suggested:

    animalMap.forEach(
            (key, value) -> {
                if (value != null) {
                    myMap.put(key, value);
                } else {
                    myList.add(key);
                }
            }
    );

Replacing all non-alphanumeric characters with empty strings

Solution:

value.replaceAll("[^A-Za-z0-9]", "")

Explanation:

[^abc] When a caret ^ appears as the first character inside square brackets, it negates the pattern. This pattern matches any character except a or b or c.

Looking at the keyword as two function:

  • [(Pattern)] = match(Pattern)
  • [^(Pattern)] = notMatch(Pattern)

Moreover regarding a pattern:

  • A-Z = all characters included from A to Z

  • a-z = all characters included from a to z

  • 0=9 = all characters included from 0 to 9

Therefore it will substitute all the char NOT included in the pattern

"This operation requires IIS integrated pipeline mode."

Your Application Pool is in classic mode but your Application need integrated mode to fire. change it to Integrated Mode:

  1. Open IIS Manager

  2. Application Pool

  3. Select pool that your app are run in it

  4. In right panel select Basic Setting

  5. Manage Pipeline Mode change to Integrated

How do I lock the orientation to portrait mode in a iPhone Web Application?

You can specify CSS styles based on viewport orientation: Target the browser with body[orient="landscape"] or body[orient="portrait"]

http://www.evotech.net/blog/2007/07/web-development-for-the-iphone/

However...

Apple's approach to this issue is to allow the developer to change the CSS based on the orientation change but not to prevent re-orientation completely. I found a similar question elsewhere:

http://ask.metafilter.com/99784/How-can-I-lock-iPhone-orientation-in-Mobile-Safari

rewrite a folder name using .htaccess

try:

RewriteRule ^/apple(.*)?$ /folder1$1 [NC]

Where the folder you want to appear in the url is in the first part of the statement - this is what it will match against and the second part 'rewrites' it to your existing folder. the [NC] flag means that it will ignore case differences eg Apple/ will still forward.

See here for a tutorial: http://www.sitepoint.com/article/guide-url-rewriting/

There is also a nice test utility for windows you can download from here: http://www.helicontech.com/download/rxtest.zip Just to note for the tester you need to leave out the domain name - so the test would be against /folder1/login.php

to redirect from /folder1 to /apple try this:

RewriteRule ^/folder1(.*)?$ /apple$1 [R]

to redirect and then rewrite just combine the above in the htaccess file:

RewriteRule ^/folder1(.*)?$ /apple$1 [R]
RewriteRule ^/apple(.*)?$ /folder1$1 [NC]

How to Detect Browser Window /Tab Close Event?

my solution is similar to the solution given by Server Themes. Do check it once:

localStorage.setItem("validNavigation", false);
$(document).on('keypress', function (e) {
    if (e.keyCode == 116) {
        localStorage.setItem("validNavigation", true);
    }
});

// Attach the event click for all links in the page
$(document).on("click", "a", function () {
    localStorage.setItem("validNavigation", true);
});

// Attach the event submit for all forms in the page
$(document).on("submit", "form", function () {
    localStorage.setItem("validNavigation", true);
});

// Attach the event click for all inputs in the page
$(document).bind("click", "input[type=submit]", function () {
    localStorage.setItem("validNavigation", true);
});

$(document).bind("click", "button[type=submit]", function () {
    localStorage.setItem("validNavigation", true);
});
window.onbeforeunload = function (event) {

    if (localStorage.getItem("validNavigation") === "false") {
        event.returnValue = "Write something clever here..";
        console.log("Test success!");
        localStorage.setItem("validNavigation", false);
    }
};

If you put the breakpoints correctly on the browser page, the if condition will be true only when the browser is about to be closed or the tab is about to be closed.

Check this link for reference: https://www.oodlestechnologies.com/blogs/Capture-Browser-Or-Tab-Close-Event-Jquery-Javascript/

Toggle Checkboxes on/off

A better approach and UX

$('.checkall').on('click', function() {
   var $checks  = $('checks');
   var $ckall = $(this);

    $.each($checks, function(){
        $(this).prop("checked", $ckall.prop('checked'));
    });
});

$('checks').on('click', function(e){
   $('.checkall').prop('checked', false);
});

Format output string, right alignment

Simple tabulation of the output:

a = 0.3333333
b = 200/3
print("variable a    variable b")
print("%10.2f    %10.2f" % (a, b))

output:

variable a    variable b
      0.33         66.67

%10.2f: 10 is the minimum length and 2 is the number of decimal places.

How to add Android Support Repository to Android Studio?

Found a solution.

1) Go to where your SDK is located that android studio/eclipse is using. If you are using Android studio, go to extras\android\m2repository\com\android\support\. If you are using eclipse, go to \extras\android\support\

2) See what folders you have, for me I had gridlayout-v7, support-v4 and support-v13.

3) click into support-v4 and see what number the following folder is, mine was named 13.0

Since you are using "com.android.support:support-v4:18.0.+", change this to reflect what version you have, for example I have support-v4 so first part v4 stays the same. Since the next path is 13.0, change your 18.0 to:

"com.android.support:support-v4:13.0.+"

This worked for me, hope it helps!

Update:

I noticed I had android studio set up with the wrong SDK which is why originally had difficulty updating! The path should be C:\Users\Username\AppData\Local\Android\android-sdk\extras\

Also note, if your SDK is up to date, the code will be:

"com.android.support:support-v4:19.0.+"

How to create a directory using Ansible

You can create a directory. using

# create a directory if it doesn't exist
- file: path=/src/www state=directory mode=0755

You can also consult http://docs.ansible.com/ansible/file_module.html for further details regaridng directory and file system.

Custom li list-style with font-awesome icon

As per the Font Awesome Documentation:

<ul class="fa-ul">
  <li><i class="fa-li fa fa-check"></i>Barbabella</li>
  <li><i class="fa-li fa fa-check"></i>Barbaletta</li>
  <li><i class="fa-li fa fa-check"></i>Barbalala</li>
</ul>

Or, using Jade:

ul.fa-ul
  li
    i.fa-li.fa.fa-check
    | Barbabella
  li
    i.fa-li.fa.fa-check
    | Barbaletta
  li
    i.fa-li.fa.fa-check
    | Barbalala

Insert into ... values ( SELECT ... FROM ... )

You could try this if you want to insert all column using SELECT * INTO table.

SELECT  *
INTO    Table2
FROM    Table1;

Create a symbolic link of directory in Ubuntu

In script is usefull something like this:

if [ ! -d /etc/nginx ]; then ln -s /usr/local/nginx/conf/ /etc/nginx > /dev/null 2>&1; fi

it prevents before re-create "bad" looped symlink after re-run script

Java SSLException: hostname in certificate didn't match

The certificate verification process will always verify the DNS name of the certificate presented by the server, with the hostname of the server in the URL used by the client.

The following code

HttpPost post = new HttpPost("https://74.125.236.52/accounts/ClientLogin");

will result in the certificate verification process verifying whether the common name of the certificate issued by the server, i.e. www.google.com matches the hostname i.e. 74.125.236.52. Obviously, this is bound to result in failure (you could have verified this by browsing to the URL https://74.125.236.52/accounts/ClientLogin with a browser, and seen the resulting error yourself).

Supposedly, for the sake of security, you are hesitant to write your own TrustManager (and you musn't unless you understand how to write a secure one), you ought to look at establishing DNS records in your datacenter to ensure that all lookups to www.google.com will resolve to 74.125.236.52; this ought to be done either in your local DNS servers or in the hosts file of your OS; you might need to add entries to other domains as well. Needless to say, you will need to ensure that this is consistent with the records returned by your ISP.

GIT: Checkout to a specific folder

Use git archive branch-index | tar -x -C your-folder-on-PC to clone a branch to another folder. I think, then you can copy any file that you need

git rebase fatal: Needed a single revision

Check that you spelled the branch name correctly. I was rebasing a story branch (i.e. branch_name) and forgot the story part. (i.e. story/branch_name) and then git spit this error at me which didn't make much sense in this context.

Why should C++ programmers minimize use of 'new'?

One notable reason to avoid overusing the heap is for performance -- specifically involving the performance of the default memory management mechanism used by C++. While allocation can be quite quick in the trivial case, doing a lot of new and delete on objects of non-uniform size without strict order leads not only to memory fragmentation, but it also complicates the allocation algorithm and can absolutely destroy performance in certain cases.

That's the problem that memory pools where created to solve, allowing to to mitigate the inherent disadvantages of traditional heap implementations, while still allowing you to use the heap as necessary.

Better still, though, to avoid the problem altogether. If you can put it on the stack, then do so.

Is it possible to use std::string in a constexpr?

Since the problem is the non-trivial destructor so if the destructor is removed from the std::string, it's possible to define a constexpr instance of that type. Like this

struct constexpr_str {
    char const* str;
    std::size_t size;

    // can only construct from a char[] literal
    template <std::size_t N>
    constexpr constexpr_str(char const (&s)[N])
        : str(s)
        , size(N - 1) // not count the trailing nul
    {}
};

int main()
{
    constexpr constexpr_str s("constString");

    // its .size is a constexpr
    std::array<int, s.size> a;
    return 0;
}

How to sort with lambda in Python

Use

a = sorted(a, key=lambda x: x.modified, reverse=True)
#             ^^^^

On Python 2.x, the sorted function takes its arguments in this order:

sorted(iterable, cmp=None, key=None, reverse=False)

so without the key=, the function you pass in will be considered a cmp function which takes 2 arguments.

How can I solve the error 'TS2532: Object is possibly 'undefined'?

With the release of TypeScript 3.7, optional chaining (the ? operator) is now officially available.

As such, you can simplify your expression to the following:

const data = change?.after?.data();

You may read more about it from that version's release notes, which cover other interesting features released on that version.

Run the following to install the latest stable release of TypeScript.

npm install typescript

That being said, Optional Chaining can be used alongside Nullish Coalescing to provide a fallback value when dealing with null or undefined values

const data = change?.after?.data() ?? someOtherData();

Sending data back to the Main Activity in Android

Another way of achieving the desired result which may be better depending on your situation is to create a listener interface.

By making the parent activity listen to an interface that get triggered by the child activity while passing the required data as a parameter can create a similar set of circumstance

What's the difference between ngOnInit and ngAfterViewInit of Angular2?

Content is what is passed as children. View is the template of the current component.

The view is initialized before the content and ngAfterViewInit() is therefore called before ngAfterContentInit().

** ngAfterViewInit() is called when the bindings of the children directives (or components) have been checked for the first time. Hence its perfect for accessing and manipulating DOM with Angular 2 components. As @Günter Zöchbauer mentioned before is correct @ViewChild() hence runs fine inside it.

Example:

@Component({
    selector: 'widget-three',
    template: `<input #input1 type="text">`
})
export class WidgetThree{
    @ViewChild('input1') input1;

    constructor(private renderer:Renderer){}

    ngAfterViewInit(){
        this.renderer.invokeElementMethod(
            this.input1.nativeElement,
            'focus',
            []
        )
    }
}

How to adjust layout when soft keyboard appears

Add this line in your Manifest where your Activity is called

android:windowSoftInputMode="adjustPan|adjustResize"

or

you can add this line in your onCreate

getWindow().setSoftInputMode(WindowManager.LayoutParams.SOFT_INPUT_STATE_VISIBLE|WindowManager.LayoutParams.SOFT_INPUT_ADJUST_RESIZE);

How do I concatenate two lists in Python?

list(set(listone) | set(listtwo))

The above code, does not preserve order, removes duplicate from each list (but not from the concatenated list)

HTML5 Canvas vs. SVG vs. div

To add to this, I've been doing a diagram application, and initially started out with canvas. The diagram consists of many nodes, and they can get quite big. The user can drag elements in the diagram around.

What I found was that on my Mac, for very large images, SVG is superior. I have a MacBook Pro 2013 13" Retina, and it runs the fiddle below quite well. The image is 6000x6000 pixels, and has 1000 objects. A similar construction in canvas was impossible to animate for me when the user was dragging objects around in the diagram.

On modern displays you also have to account for different resolutions, and here SVG gives you all of this for free.

Fiddle: http://jsfiddle.net/knutsi/PUcr8/16/

Fullscreen: http://jsfiddle.net/knutsi/PUcr8/16/embedded/result/

var wiggle_factor = 0.0;
nodes = [];

// create svg:
var svg = document.createElementNS("http://www.w3.org/2000/svg", "svg");
svg.setAttribute('style', 'border: 1px solid black');
svg.setAttribute('width', '6000');
svg.setAttribute('height', '6000');

svg.setAttributeNS("http://www.w3.org/2000/xmlns/", "xmlns:xlink",
    "http://www.w3.org/1999/xlink");

document.body.appendChild(svg);


function makeNode(wiggle) {
    var node = document.createElementNS("http://www.w3.org/2000/svg", "g");
    var node_x = (Math.random() * 6000);
    var node_y = (Math.random() * 6000);
    node.setAttribute("transform", "translate(" + node_x + ", " + node_y +")");

    // circle:
    var circ = document.createElementNS("http://www.w3.org/2000/svg", "circle");
    circ.setAttribute( "id","cir")
    circ.setAttribute( "cx", 0 + "px")
    circ.setAttribute( "cy", 0 + "px")
    circ.setAttribute( "r","100px");
    circ.setAttribute('fill', 'red');
    circ.setAttribute('pointer-events', 'inherit')

    // text:
    var text = document.createElementNS("http://www.w3.org/2000/svg", "text");
    text.textContent = "This is a test! ÅÆØ";

    node.appendChild(circ);
    node.appendChild(text);

    node.x = node_x;
    node.y = node_y;

    if(wiggle)
        nodes.push(node)
    return node;
}

// populate with 1000 nodes:
for(var i = 0; i < 1000; i++) {
    var node = makeNode(true);
    svg.appendChild(node);
}

// make one mapped to mouse:
var bnode = makeNode(false);
svg.appendChild(bnode);

document.body.onmousemove=function(event){
    bnode.setAttribute("transform","translate(" +
        (event.clientX + window.pageXOffset) + ", " +
        (event.clientY + window.pageYOffset) +")");
};

setInterval(function() {
    wiggle_factor += 1/60;
    nodes.forEach(function(node) {

        node.setAttribute("transform", "translate(" 
                          + (Math.sin(wiggle_factor) * 200 + node.x) 
                          + ", " 
                          + (Math.sin(wiggle_factor) * 200 + node.y) 
                          + ")");        
    })
},1000/60);

How to find common elements from multiple vectors?

intersect_all <- function(a,b,...){
  all_data <- c(a,b,...)
  require(plyr)
  count_data<- length(list(a,b,...))
  freq_dist <- count(all_data)
  intersect_data <- freq_dist[which(freq_dist$freq==count_data),"x"]
  intersect_data
}


intersect_all(a,b,c)

UPDATE EDIT A simpler code

intersect_all <- function(a,b,...){
  Reduce(intersect, list(a,b,...))
}

intersect_all(a,b,c)

Execute a terminal command from a Cocoa app

You can use NSTask. Here's an example that would run '/usr/bin/grep foo bar.txt'.

int pid = [[NSProcessInfo processInfo] processIdentifier];
NSPipe *pipe = [NSPipe pipe];
NSFileHandle *file = pipe.fileHandleForReading;

NSTask *task = [[NSTask alloc] init];
task.launchPath = @"/usr/bin/grep";
task.arguments = @[@"foo", @"bar.txt"];
task.standardOutput = pipe;

[task launch];

NSData *data = [file readDataToEndOfFile];
[file closeFile];

NSString *grepOutput = [[NSString alloc] initWithData: data encoding: NSUTF8StringEncoding];
NSLog (@"grep returned:\n%@", grepOutput);

NSPipe and NSFileHandle are used to redirect the standard output of the task.

For more detailed information on interacting with the operating system from within your Objective-C application, you can see this document on Apple's Development Center: Interacting with the Operating System.

Edit: Included fix for NSLog problem

If you are using NSTask to run a command-line utility via bash, then you need to include this magic line to keep NSLog working:

//The magic line that keeps your log where it belongs
task.standardOutput = pipe;

An explanation is here: https://web.archive.org/web/20141121094204/https://cocoadev.com/HowToPipeCommandsWithNSTask

How to select rows for a specific date, ignoring time in SQL Server

Try this:

true
select cast(salesDate as date) [date] from sales where salesDate = '2010/11/11'
false
select cast(salesDate as date) [date] from sales where salesDate = '11/11/2010'

Correctly Parsing JSON in Swift 3

A big change that happened with Xcode 8 Beta 6 for Swift 3 was that id now imports as Any rather than AnyObject.

This means that parsedData is returned as a dictionary of most likely with the type [Any:Any]. Without using a debugger I could not tell you exactly what your cast to NSDictionary will do but the error you are seeing is because dict!["currently"]! has type Any

So, how do you solve this? From the way you've referenced it, I assume dict!["currently"]! is a dictionary and so you have many options:

First you could do something like this:

let currentConditionsDictionary: [String: AnyObject] = dict!["currently"]! as! [String: AnyObject]  

This will give you a dictionary object that you can then query for values and so you can get your temperature like this:

let currentTemperatureF = currentConditionsDictionary["temperature"] as! Double

Or if you would prefer you can do it in line:

let currentTemperatureF = (dict!["currently"]! as! [String: AnyObject])["temperature"]! as! Double

Hopefully this helps, I'm afraid I have not had time to write a sample app to test it.

One final note: the easiest thing to do, might be to simply cast the JSON payload into [String: AnyObject] right at the start.

let parsedData = try JSONSerialization.jsonObject(with: data as Data, options: .allowFragments) as! Dictionary<String, AnyObject>

Similarity String Comparison in Java

You can achieve this using the apache commons java library. Take a look at these two functions within it:
- getLevenshteinDistance
- getFuzzyDistance

Eclipse - debugger doesn't stop at breakpoint

Usually when this happens to me (rare but it does) means that the code being executed is different than the code in the editor. It will happen from time to time for Eclipse that the built classes and the code in editor are out of sync. When that happens I get all sort of weird debugger behavior (debugging empty lines, skipping lines of codes etc).

Restarting Eclipse, clean all projects and rebuild everything usually clears things up. I had also the Maven plugins (older versions... had not had it for a while now) that had a tendency to do that too.

Otherwise it might be a bug, maybe the one Vineet stated,

Hope this helps

Select rows of a matrix that meet a condition

If your matrix is called m, just use :

R> m[m$three == 11, ]

C# removing items from listbox

You can't modify the references in an enumerator whilst you enumerate over it; you must keep track of the ones to remove then remove them.

This is an example of the work around:

List<string> listbox = new List<string>();
List<object> toRemove = new List<object>();

foreach (string item in listbox)
{
    string removelistitem = "OBJECT";
    if (item.Contains(removelistitem))
    {
        toRemove.Add(item);
    }
}

foreach (string item in toRemove)
{
    listbox.Remove(item);
}

But if you're using c#3.5, you could say something like this.

listbox.Items = listbox.Items.Select(n => !n.Contains("OBJECT"));

how to align text vertically center in android

just use like this to make anything to center

 android:layout_gravity="center"
 android:gravity="center"

updated :

android:layout_gravity="center|right"
android:gravity="center|right"

Updated : Just remove MarginBottom from your textview.. Do like this.. for your textView

<LinearLayout
        android:id="@+id/linearLayout5"
        android:layout_width="fill_parent"
        android:layout_height="wrap_content"
        android:layout_gravity="center"  >

        <TextView
            android:id="@+id/textView2"
            android:layout_width="fill_parent"
            android:layout_height="wrap_content"
            android:layout_gravity="center" 
            android:gravity="center|right"
            android:text="hello" 
            android:textSize="20dp" />
    </LinearLayout>

Can you have multiple $(document).ready(function(){ ... }); sections?

You can also do it the following way:

<html>
<head>
<script src="https://ajax.googleapis.com/ajax/libs/jquery/3.3.1/jquery.min.js"></script>
<script>
 $(document).ready(function(){
     $("#hide").click(function(){
     $("#test").hide();
     });
     $("#show").click(function(){
     $("#test").show();
     });
 });
</script>
</head>

<body>
<h2>This is a test of jQuery!</h2>
<p id="test">This is a hidden paragraph.</p>
<button id="hide">Click me to hide</button>
<button id="show">Click me to show</button>
</body>

the previous answers showed using multiple named functions inside a single .ready block, or a single unnamed function in the .ready block, with another named function outside the .ready block. I found this question while researching if there was a way to have multiple unnamed functions inside the .ready block - I could not get the syntax correct. I finally figured it out, and hoped that by posting my test code I would help others looking for the answer to the same question I had

WCF - How to Increase Message Size Quota

I found the easy way

--- right click the webconfig or app config file and click EDIT WCF CONFIGURATION and got to bingdigs ans select yore service and right side show maxReciveMessageSize give a large number ---

How to force a line break in a long word in a DIV?

Found that using the following worked across most major browsers (Chrome, IE, Safari iOS/OSX) except Firefox (v50.0.2) when using flexbox and relying on width: auto.

.your_element {
    word-wrap: break-word;   
    overflow-wrap: break-word;
    word-break: break-word;
}

Note: you may need to add browser vendor prefixes if you are not using an autoprefixer.

Another thing to watch out for is text using &nbsp; for spacing can cause line breaks mid-word.

Difference between logger.info and logger.debug

Just a clarification about the set of all possible levels, that are:

ALL < TRACE < DEBUG < INFO < WARN < ERROR < FATAL < OFF

Disable Required validation attribute under certain circumstances

The cleanest way here I believe is going to disable your client side validation and on the server side you will need to:

  1. ModelState["SomeField"].Errors.Clear (in your controller or create an action filter to remove errors before the controller code is executed)
  2. Add ModelState.AddModelError from your controller code when you detect a violation of your detected issues.

Seems even a custom view model here wont solve the problem because the number of those 'pre answered' fields could vary. If they dont then a custom view model may indeed be the easiest way, but using the above technique you can get around your validations issues.

Latex - Change margins of only a few pages

Use the "geometry" package and write \newgeometry{left=3cm,bottom=0.1cm} where you want to change your margins. When you want to reset your margins, you write \restoregeometry.

How do I check for a network connection?

You can check for a network connection in .NET 2.0 using GetIsNetworkAvailable():

System.Net.NetworkInformation.NetworkInterface.GetIsNetworkAvailable()

To monitor changes in IP address or changes in network availability use the events from the NetworkChange class:

System.Net.NetworkInformation.NetworkChange.NetworkAvailabilityChanged
System.Net.NetworkInformation.NetworkChange.NetworkAddressChanged

Get user location by IP address

I have tried using http://ipinfo.io and this JSON API works perfectly. First, you need to add the below mentioned namespaces:

using System.Linq;
using System.Web; 
using System.Web.UI.WebControls;
using System.Net;
using System.IO;
using System.Xml;
using System.Collections.Specialized;

For localhost it will give dummy data as AU. You can try hardcoding your IP and get results:

namespace WebApplication4
{
    public partial class WebForm1 : System.Web.UI.Page
    {

        protected void Page_Load(object sender, EventArgs e)
         {

          string VisitorsIPAddr = string.Empty;
          //Users IP Address.                
          if (HttpContext.Current.Request.ServerVariables["HTTP_X_FORWARDED_FOR"] != null)
          {
              //To get the IP address of the machine and not the proxy
              VisitorsIPAddr =   HttpContext.Current.Request.ServerVariables["HTTP_X_FORWARDED_FOR"].ToString();
          }
          else if (HttpContext.Current.Request.UserHostAddress.Length != 0)
          {
              VisitorsIPAddr = HttpContext.Current.Request.UserHostAddress;`enter code here`
          }

          string res = "http://ipinfo.io/" + VisitorsIPAddr + "/city";
          string ipResponse = IPRequestHelper(res);

        }

        public string IPRequestHelper(string url)
        {

            string checkURL = url;
            HttpWebRequest objRequest = (HttpWebRequest)WebRequest.Create(url);
            HttpWebResponse objResponse = (HttpWebResponse)objRequest.GetResponse();
            StreamReader responseStream = new StreamReader(objResponse.GetResponseStream());
            string responseRead = responseStream.ReadToEnd();
            responseRead = responseRead.Replace("\n", String.Empty);
            responseStream.Close();
            responseStream.Dispose();
            return responseRead;
        }


    }
}

How to pass in password to pg_dump?

Correct me if I'm wrong, but if the system user is the same as the database user, PostgreSQL won't ask for the password - it relies on the system for authentication. This might be a matter of configuration.

Thus, when I wanted the database owner postgres to backup his databases every night, I could create a crontab for it: crontab -e -u postgres. Of course, postgres would need to be allowed to execute cron jobs; thus it must be listed in /etc/cron.allow, or /etc/cron.deny must be empty.

How can I add a username and password to Jenkins?

Assuming you have Manage Jenkins > Configure Global Security > Enable Security and Jenkins Own User Database checked you would go to:

  • Manage Jenkins > Manage Users > Create User

List of All Locales and Their Short Codes?

Language List

List of all languages with names and ISO 639-1 codes in all languages and all data formats.

Formats Available

  • Text
  • JSON
  • YAML
  • XML
  • HTML
  • CSV
  • SQL (MySQL, PostgreSQL, SQLite)
  • PHP

https://github.com/umpirsky/language-list

What does this error mean: "error: expected specifier-qualifier-list before 'type_name'"?

I was able to sort this out using Gorgando's fix, but instead of moving imports away, I commented each out individually, built the app, then edited accordingly until I got rid of them.

Bash: Echoing a echo command with a variable in bash

You just need to use single quotes:

$ echo "$TEST"
test
$ echo '$TEST'
$TEST

Inside single quotes special characters are not special any more, they are just normal characters.

How to run only one task in ansible playbook?

I would love the ability to use a role as a collection of tasks such that, in my playbook, I can choose which subset of tasks to run. Unfortunately, the playbook can only load them all in and then you have to use the --tags option on the cmdline to choose which tasks to run. The problem with this is that all of the tasks will run unless you remember to set --tags or --skip-tags.

I have set up some tasks, however, with a when: clause that will only fire if a var is set.

e.g.

# role/stuff/tasks/main.yml
- name: do stuff
  when: stuff|default(false)

Now, this task will not fire by default, but only if I set the stuff=true

$ ansible-playbook -e '{"stuff":true}'

or in a playbook:

roles:
- {"role":"stuff", "stuff":true}

How to extract epoch from LocalDate and LocalDateTime?

The classes LocalDate and LocalDateTime do not contain information about the timezone or time offset, and seconds since epoch would be ambigious without this information. However, the objects have several methods to convert them into date/time objects with timezones by passing a ZoneId instance.

LocalDate

LocalDate date = ...;
ZoneId zoneId = ZoneId.systemDefault(); // or: ZoneId.of("Europe/Oslo");
long epoch = date.atStartOfDay(zoneId).toEpochSecond();

LocalDateTime

LocalDateTime time = ...;
ZoneId zoneId = ZoneId.systemDefault(); // or: ZoneId.of("Europe/Oslo");
long epoch = time.atZone(zoneId).toEpochSecond();

What happens to a declared, uninitialized variable in C? Does it have a value?

That depends. If that definition is global (outside any function) then num will be initialized to zero. If it's local (inside a function) then its value is indeterminate. In theory, even attempting to read the value has undefined behavior -- C allows for the possibility of bits that don't contribute to the value, but have to be set in specific ways for you to even get defined results from reading the variable.

Evaluate if list is empty JSTL

empty is an operator:

The empty operator is a prefix operation that can be used to determine whether a value is null or empty.

<c:if test="${empty myObject.featuresList}">

Why can't I use switch statement on a String?

For years we've been using a(n open source) preprocessor for this.

//#switch(target)
case "foo": code;
//#end

Preprocessed files are named Foo.jpp and get processed into Foo.java with an ant script.

Advantage is it is processed into Java that runs on 1.0 (although typically we only supported back to 1.4). Also it was far easier to do this (lots of string switches) compared to fudging it with enums or other workarounds - code was a lot easier to read, maintain, and understand. IIRC (can't provide statistics or technical reasoning at this point) it was also faster than the natural Java equivalents.

Disadvantages are you aren't editing Java so it's a bit more workflow (edit, process, compile/test) plus an IDE will link back to the Java which is a little convoluted (the switch becomes a series of if/else logic steps) and the switch case order is not maintained.

I wouldn't recommend it for 1.7+ but it's useful if you want to program Java that targets earlier JVMs (since Joe public rarely has the latest installed).

You can get it from SVN or browse the code online. You'll need EBuild to build it as-is.

Call Python function from MATLAB

Like Daniel said you can run python commands directly from Matlab using the py. command. To run any of the libraries you just have to make sure Malab is running the python environment where you installed the libraries:

On a Mac:

  • Open a new terminal window;

  • type: which python (to find out where the default version of python is installed);

  • Restart Matlab;

  • type: pyversion('/anaconda2/bin/python'), in the command line (obviously replace with your path).
  • You can now run all the libraries in your default python installation.

For example:

py.sys.version;

py.sklearn.cluster.dbscan

Which comes first in a 2D array, rows or columns?

Instinctively one thinks geometrically: horizontal (X) axis and then vertical (Y) axis. This is not, however, the case with a 2D array, rows come first and then columns.

Consider the following analogy: in geometry one walks to the ladder (X axis) and climbs it (Y axis). Conversely, in Java one descends the ladder (rows) and walks away (columns).

ADB Shell Input Events

I wrote a simple Powershell script for windows users to map keys to adb shell input events. And controll an Android device remotely over LAN. I don't know if anyone finds it usefull, but I'll share it anyways.

$ip = 192.168.1.8
cd D:\Android\android-sdk-windows\platform-tools\; .\adb.exe disconnect $ip; .\adb.exe connect $ip
$adbKeyNum = @{LeftWindows = "1"; F1 = "3"; Enter = "66"; UpArrow = "19"; DownArrow = "20"; LeftArrow = "21"; RightArrow = "22"; Add = "24";
        Subtract = "25"; Backspace = "4"; P = "26"}

while(1 -eq 1){
    $keyPress = [Console]::ReadKey($true).Key
    if ([string]$keyPress -eq "F10"){
        .\adb.exe disconnect $ip
        exit
    }
    elseif ([string]$keyPress -eq "F6"){
        $string = Read-Host -Prompt 'Input the string: '
        .\adb.exe shell input text $string
    }
    elseif ($adbKeyNum.ContainsKey([string]$keyPress)){
        echo $adbKeyNum.Get_Item([string]$keyPress)
        .\adb.exe shell input keyevent $adbKeyNum.Get_Item([string]$keyPress)
    }
}

Failure [INSTALL_FAILED_UPDATE_INCOMPATIBLE] even if app appears to not be installed

Uninstalling the application would be enough to avoid this problem.

INSTALL_FAILED_UPDATE_INCOMPATIBLE

but sometimes even uninstalling the message is raised again, it occurs in Android OS 5.0 +, so this is the solution:

Go to Settings > Apps and you will find your app with the message:

"Not installed for this user"

, we have to uninstall manually for all users with the option:

"Uninstall for all users"

Check if value already exists within list of dictionaries?

Maybe this helps:

a = [{ 'main_color': 'red', 'second_color':'blue'},
     { 'main_color': 'yellow', 'second_color':'green'},
     { 'main_color': 'yellow', 'second_color':'blue'}]

def in_dictlist((key, value), my_dictlist):
    for this in my_dictlist:
        if this[key] == value:
            return this
    return {}

print in_dictlist(('main_color','red'), a)
print in_dictlist(('main_color','pink'), a)

Getting value of selected item in list box as string

If you want to retrieve the item selected from listbox, here is the code...

String SelectedItem = listBox1.SelectedItem.Value;

Error during installing HAXM, VT-X not working

I ran into same issue, and problem was that virtualization was not enabled by default on my machine, you need to enter BIOS setting and enable it incase its disabled. Detailed Instructions available here on how to resolve this and enable virtualization on your machine.

https://maksbay.blogspot.in/2017/12/trying-to-set-up-android-emulators-you.html

How do I fire an event when a iframe has finished loading in jQuery?

Here is what I do for any action and it works in Firefox, IE, Opera, and Safari.

<script type="text/javascript">
  $(document).ready(function(){
    doMethod();
  });
  function actionIframe(iframe)
  {
    ... do what ever ...
  }
  function doMethod()
  {   
    var iFrames = document.getElementsByTagName('iframe');

    // what ever action you want.
    function iAction()
    {
      // Iterate through all iframes in the page.
      for (var i = 0, j = iFrames.length; i < j; i++)
      {
        actionIframe(iFrames[i]);
      }
    }

    // Check if browser is Safari or Opera.
    if ($.browser.safari || $.browser.opera)
    {
      // Start timer when loaded.
      $('iframe').load(function()
      {
        setTimeout(iAction, 0);
      }
      );

      // Safari and Opera need something to force a load.
      for (var i = 0, j = iFrames.length; i < j; i++)
      {
         var iSource = iFrames[i].src;
         iFrames[i].src = '';
         iFrames[i].src = iSource;
      }
    }
    else
    {
      // For other good browsers.
      $('iframe').load(function()
      {
        actionIframe(this);
      }
      );
    }
  }
</script>

Reading from stdin

You can do something like this to read 10 bytes:

char buffer[10];
read(STDIN_FILENO, buffer, 10);

remember read() doesn't add '\0' to terminate to make it string (just gives raw buffer).

To read 1 byte at a time:

char ch;
while(read(STDIN_FILENO, &ch, 1) > 0)
{
 //do stuff
}

and don't forget to #include <unistd.h>, STDIN_FILENO defined as macro in this file.

There are three standard POSIX file descriptors, corresponding to the three standard streams, which presumably every process should expect to have:

Integer value   Name
       0        Standard input (stdin)
       1        Standard output (stdout)
       2        Standard error (stderr)

So instead STDIN_FILENO you can use 0.

Edit:
In Linux System you can find this using following command:

$ sudo grep 'STDIN_FILENO' /usr/include/* -R | grep 'define'
/usr/include/unistd.h:#define   STDIN_FILENO    0   /* Standard input.  */

Notice the comment /* Standard input. */

Django, creating a custom 500/404 error page

If all you need is to show custom pages which have some fancy error messages for your site when DEBUG = False, then add two templates named 404.html and 500.html in your templates directory and it will automatically pick up this custom pages when a 404 or 500 is raised.

How to fix error Base table or view not found: 1146 Table laravel relationship table?

try checking in the app if you are using the tables before it's created such as appServiceProvider.php

you might be calling the table without being created it, if you are, comment it then run php artisan migrate.

MongoDB: Is it possible to make a case-insensitive query?

One very important thing to keep in mind when using a Regex based query - When you are doing this for a login system, escape every single character you are searching for, and don't forget the ^ and $ operators. Lodash has a nice function for this, should you be using it already:

db.stuff.find({$regex: new RegExp(_.escapeRegExp(bar), $options: 'i'})

Why? Imagine a user entering .* as his username. That would match all usernames, enabling a login by just guessing any user's password.

Accessing UI (Main) Thread safely in WPF

You can use

Dispatcher.Invoke(Delegate, object[])

on the Application's (or any UIElement's) dispatcher.

You can use it for example like this:

Application.Current.Dispatcher.Invoke(new Action(() => { /* Your code here */ }));

or

someControl.Dispatcher.Invoke(new Action(() => { /* Your code here */ }));

PHP - warning - Undefined property: stdClass - fix?

Depending on whether you're looking for a member or method, you can use either of these two functions to see if a member/method exists in a particular object:

http://php.net/manual/en/function.method-exists.php

http://php.net/manual/en/function.property-exists.php

More generally if you want all of them:

http://php.net/manual/en/function.get-object-vars.php

ASP.NET MVC 404 Error Handling

What I can recomend is to look on FilterAttribute. For example MVC already has HandleErrorAttribute. You can customize it to handle only 404. Reply if you are interesed I will look example.

BTW

Solution(with last route) that you have accepted in previous question does not work in much of the situations. Second solution with HandleUnknownAction will work but require to make this change in each controller or to have single base controller.

My choice is a solution with HandleUnknownAction.

What does a "Cannot find symbol" or "Cannot resolve symbol" error mean?

enter image description here

I solved this error like this... The craziness of android. I had the package name as Adapter and the I refactor the name to adapter with an "a" instead of "A" and solved the error.

Storing Images in PostgreSQL

In the database, there are two options:

  • bytea. Stores the data in a column, exported as part of a backup. Uses standard database functions to save and retrieve. Recommended for your needs.
  • blobs. Stores the data externally, not normally exported as part of a backup. Requires special database functions to save and retrieve.

I've used bytea columns with great success in the past storing 10+gb of images with thousands of rows. PG's TOAST functionality pretty much negates any advantage that blobs have. You'll need to include metadata columns in either case for filename, content-type, dimensions, etc.

PostgreSQL naming conventions

There isn't really a formal manual, because there's no single style or standard.

So long as you understand the rules of identifier naming you can use whatever you like.

In practice, I find it easier to use lower_case_underscore_separated_identifiers because it isn't necessary to "Double Quote" them everywhere to preserve case, spaces, etc.

If you wanted to name your tables and functions "@MyA??! ""betty"" Shard$42" you'd be free to do that, though it'd be pain to type everywhere.

The main things to understand are:

  • Unless double-quoted, identifiers are case-folded to lower-case, so MyTable, MYTABLE and mytable are all the same thing, but "MYTABLE" and "MyTable" are different;

  • Unless double-quoted:

    SQL identifiers and key words must begin with a letter (a-z, but also letters with diacritical marks and non-Latin letters) or an underscore (_). Subsequent characters in an identifier or key word can be letters, underscores, digits (0-9), or dollar signs ($).

  • You must double-quote keywords if you wish to use them as identifiers.

In practice I strongly recommend that you do not use keywords as identifiers. At least avoid reserved words. Just because you can name a table "with" doesn't mean you should.

Import a custom class in Java

If your classes are in the same package, you won't need to import. To call a method from class B in class A, you should use classB.methodName(arg)

Filter rows which contain a certain string

Solution

It is possible to use str_detect of the stringr package included in the tidyverse package. str_detect returns True or False as to whether the specified vector contains some specific string. It is possible to filter using this boolean value. See Introduction to stringr for details about stringr package.

library(tidyverse)
# - Attaching packages -------------------- tidyverse 1.2.1 -
# ? ggplot2 2.2.1     ? purrr   0.2.4
# ? tibble  1.4.2     ? dplyr   0.7.4
# ? tidyr   0.7.2     ? stringr 1.2.0
# ? readr   1.1.1     ? forcats 0.3.0
# - Conflicts --------------------- tidyverse_conflicts() -
# ? dplyr::filter() masks stats::filter()
# ? dplyr::lag()    masks stats::lag()

mtcars$type <- rownames(mtcars)
mtcars %>%
  filter(str_detect(type, 'Toyota|Mazda'))
# mpg cyl  disp  hp drat    wt  qsec vs am gear carb           type
# 1 21.0   6 160.0 110 3.90 2.620 16.46  0  1    4    4      Mazda RX4
# 2 21.0   6 160.0 110 3.90 2.875 17.02  0  1    4    4  Mazda RX4 Wag
# 3 33.9   4  71.1  65 4.22 1.835 19.90  1  1    4    1 Toyota Corolla
# 4 21.5   4 120.1  97 3.70 2.465 20.01  1  0    3    1  Toyota Corona

The good things about Stringr

We should use rather stringr::str_detect() than base::grepl(). This is because there are the following reasons.

  • The functions provided by the stringr package start with the prefix str_, which makes the code easier to read.
  • The first argument of the functions of stringr package is always the data.frame (or value), then comes the parameters.(Thank you Paolo)
object <- "stringr"
# The functions with the same prefix `str_`.
# The first argument is an object.
stringr::str_count(object) # -> 7
stringr::str_sub(object, 1, 3) # -> "str"
stringr::str_detect(object, "str") # -> TRUE
stringr::str_replace(object, "str", "") # -> "ingr"
# The function names without common points.
# The position of the argument of the object also does not match.
base::nchar(object) # -> 7
base::substr(object, 1, 3) # -> "str"
base::grepl("str", object) # -> TRUE
base::sub("str", "", object) # -> "ingr"

Benchmark

The results of the benchmark test are as follows. For large dataframe, str_detect is faster.

library(rbenchmark)
library(tidyverse)

# The data. Data expo 09. ASA Statistics Computing and Graphics 
# http://stat-computing.org/dataexpo/2009/the-data.html
df <- read_csv("Downloads/2008.csv")
print(dim(df))
# [1] 7009728      29

benchmark(
  "str_detect" = {df %>% filter(str_detect(Dest, 'MCO|BWI'))},
  "grepl" = {df %>% filter(grepl('MCO|BWI', Dest))},
  replications = 10,
  columns = c("test", "replications", "elapsed", "relative", "user.self", "sys.self"))
# test replications elapsed relative user.self sys.self
# 2      grepl           10  16.480    1.513    16.195    0.248
# 1 str_detect           10  10.891    1.000     9.594    1.281

Nodejs cannot find installed module on Windows

Tried to add/edit environment variables and come to conclude that:

  1. Edit/add User variables (of the upper box) instead of System variables (of the lower part); otherwise you have to "run as administrator" to get it work.
  2. Append ;%AppData%\npm to Path in order to use it as a command line tool (if supported, like jshint and grunt-cli).
  3. Create NODE_PATH and set it %AppData%\npm\node_modules in order to require('<pkg_name>') in scripts without install it in the project directory. (But npm link is suggested for this requirement if you're working on OS with mklink such as Vista and newer.)

Test environment:

  • Win 7 (Ent., 64-bit, SP1), Node.js 4.2.4, npm 2.14.12
  • Win 8.1 (Ent., 64-bit), Node.js 0.10.30, npm 1.4.21

counting the number of lines in a text file

with for-loop:

std::ifstream myFile;
std::string line;
int lines;

myFile.open(path);

for(lines = 0; std::getline(myFile,line); lines++);

std::cout << lines << std::endl;

Is there a way to follow redirects with command line cURL?

Use the location header flag:

curl -L <URL>

Excel CSV - Number cell format

I had this issue when exporting CSV data from C# code, and resolved this by prepending the leading zero data with the tab character \t, so the data was interpreted as text rather than numeric in Excel (yet unlike prepending other characters, it wouldn't be seen).

I did like the ="001" approach, but this wouldn't allow exported CSV data to be re-imported again to my C# application without removing all this formatting from the import CSV file (instead I'll just trim the import data).

addID in jQuery?

I've used something like this before which addresses @scunliffes concern. It finds all instances of items with a class of (in this case .button), and assigns an ID and appends its index to the id name:

_x000D_
_x000D_
$(".button").attr('id', function (index) {_x000D_
 return "button-" + index;_x000D_
});
_x000D_
_x000D_
_x000D_

So let's say you have 3 items with the class name of .button on a page. The result would be adding a unique ID to all of them (in addition to their class of "button").

In this case, #button-0, #button-1, #button-2, respectively. This can come in very handy. Simply replace ".button" in the first line with whatever class you want to target, and replace "button" in the return statement with whatever you'd like your unique ID to be. Hope this helps!

Mismatched anonymous define() module

Or you can use this approach.

  • Add require.js in your code base
  • then load your script through that code

<script data-main="js/app.js" src="js/require.js"></script>

What it will do it will load your script after loading require.js.

Entity Framework - Generating Classes

I found very nice solution. Microsoft released a beta version of Entity Framework Power Tools: Entity Framework Power Tools Beta 2

There you can generate POCO classes, derived DbContext and Code First mapping for an existing database in some clicks. It is very nice!

After installation some context menu options would be added to your Visual Studio.

Right-click on a C# project. Choose Entity Framework-> Reverse Engineer Code First (Generates POCO classes, derived DbContext and Code First mapping for an existing database):

Visual Studio Context Menu

Then choose your database and click OK. That's all! It is very easy.

AttributeError: 'module' object has no attribute 'model'

It's called models.Model and not models.model (case sensitive). Fix your Poll model like this -

class Poll(models.Model):
    question = models.CharField(max_length=200) 
    pub_date = models.DateTimeField('date published')

How to get a list of all valid IP addresses in a local network?

Install nmap,

sudo apt-get install nmap

then

nmap -sP 192.168.1.*

or more commonly

nmap -sn 192.168.1.0/24

will scan the entire .1 to .254 range

This does a simple ping scan in the entire subnet to see which hosts are online.

What's the difference between console.dir and console.log?

Well, the Console Standard (as of commit ef88ec7a39fdfe79481d7d8f2159e4a323e89648) currently calls for console.dir to apply generic JavaScript object formatting before passing it to Printer (a spec-level operation), but for a single-argument console.log call, the spec ends up passing the JavaScript object directly to Printer.

Since the spec actually leaves almost everything about the Printer operation to the implementation, it's left to their discretion what type of formatting to use for console.log().

Importing Excel files into R, xlsx or xls

Update

As the Answer below is now somewhat outdated, I'd just draw attention to the readxl package. If the Excel sheet is well formatted/lain out then I would now use readxl to read from the workbook. If sheets are poorly formatted/lain out then I would still export to CSV and then handle the problems in R either via read.csv() or plain old readLines().

Original

My preferred way is to save individual Excel sheets in comma separated value (CSV) files. On Windows, these files are associated with Excel so you don't loose the double-click-open-in-Excel "feature".

CSV files can be read into R using read.csv(), or, if you are in a location or using a computer set up with some European settings (where , is used as the decimal place), using read.csv2().

These functions have sensible defaults that makes reading appropriately formatted files simple. Just keep any labels for samples or variables in the first row or column.

Added benefits of storing files in CSV are that as the files are plain text they can be passed around very easily and you can be confident they will open anywhere; one doesn't need Excel to look at or edit the data.

Failed to instantiate module [$injector:unpr] Unknown provider: $routeProvider

The ngRoute module is no longer part of the core angular.js file. If you are continuing to use $routeProvider then you will now need to include angular-route.js in your HTML:

<script src="angular.js">
<script src="angular-route.js">

API Reference

You also have to add ngRoute as a dependency for your application:

var app = angular.module('MyApp', ['ngRoute', ...]);

If instead you are planning on using angular-ui-router or the like then just remove the $routeProvider dependency from your module .config() and substitute it with the relevant provider of choice (e.g. $stateProvider). You would then use the ui.router dependency:

var app = angular.module('MyApp', ['ui.router', ...]);

Extension gd is missing from your system - laravel composer Update

On CentOS 7, try running following command:

sudo yum install php72u-gd.x86_64

How to upload a file using Java HttpClient library working with PHP

I knew I am late to the party but below is the correct way to deal with this, the key is to use InputStreamBody in place of FileBody to upload multi-part file.

   try {
        HttpClient httpclient = new DefaultHttpClient();
        HttpPost postRequest = new HttpPost("https://someserver.com/api/path/");
        postRequest.addHeader("Authorization",authHeader);
        //don't set the content type here            
        //postRequest.addHeader("Content-Type","multipart/form-data");
        MultipartEntity reqEntity = new MultipartEntity(HttpMultipartMode.BROWSER_COMPATIBLE);


        File file = new File(filePath);
        FileInputStream fileInputStream = new FileInputStream(file);
        reqEntity.addPart("parm-name", new InputStreamBody(fileInputStream,"image/jpeg","file_name.jpg"));

        postRequest.setEntity(reqEntity);
        HttpResponse response = httpclient.execute(postRequest);

        }catch(Exception e) {
            Log.e("URISyntaxException", e.toString());
   }

Returning a promise in an async function in TypeScript

When you do new Promise((resolve)... the type inferred was Promise<{}> because you should have used new Promise<number>((resolve).

It is interesting that this issue was only highlighted when the async keyword was added. I would recommend reporting this issue to the TS team on GitHub.

There are many ways you can get around this issue. All the following functions have the same behavior:

const whatever1 = () => {
    return new Promise<number>((resolve) => {
        resolve(4);
    });
};

const whatever2 = async () => {
    return new Promise<number>((resolve) => {
        resolve(4);
    });
};

const whatever3 = async () => {
    return await new Promise<number>((resolve) => {
        resolve(4);
    });
};

const whatever4 = async () => {
    return Promise.resolve(4);
};

const whatever5 = async () => {
    return await Promise.resolve(4);
};

const whatever6 = async () => Promise.resolve(4);

const whatever7 = async () => await Promise.resolve(4);

In your IDE you will be able to see that the inferred type for all these functions is () => Promise<number>.

PHP - Session destroy after closing browser

Use a keep alive.

On login:

session_start();
$_SESSION['last_action'] = time();

An ajax call every few (eg 20) seconds:

windows.setInterval(keepAliveCall, 20000);

Server side keepalive.php:

session_start();
$_SESSION['last_action'] = time();

On every other action:

session_start();
if ($_SESSION['last_action'] < time() - 30 /* be a little tolerant here */) {
  // destroy the session and quit
}

How to obtain the location of cacerts of the default java installation?

If you need to access those certs programmatically it is best to not use the file at all, but access it via the trust manager. The following code is from a OpenJDK Test case (which makes sure the built cacerts collection is not empty):

TrustManagerFactory trustManagerFactory =
    TrustManagerFactory.getInstance("PKIX");
trustManagerFactory.init((KeyStore) null);
TrustManager[] trustManagers =
    trustManagerFactory.getTrustManagers();
X509TrustManager trustManager =
    (X509TrustManager) trustManagers[0];
X509Certificate[] acceptedIssuers =
    trustManager.getAcceptedIssuers();

So you don’t have to deal with file location or keystore password.

TypeError: 'float' object is not callable

There is an operator missing, likely a *:

-3.7 need_something_here (prof[x])

The "is not callable" occurs because the parenthesis -- and lack of operator which would have switched the parenthesis into precedence operators -- make Python try to call the result of -3.7 (a float) as a function, which is not allowed.

The parenthesis are also not needed in this case, the following may be sufficient/correct:

-3.7 * prof[x]

As Legolas points out, there are other things which may need to be addressed:

2.25 * (1 - math.pow(math.e, (-3.7(prof[x])/2.25))) * (math.e, (0/2.25)))
                                  ^-- op missing
                                                    extra parenthesis --^
               valid but questionable float*tuple --^
                                     expression yields 0.0 always --^

How do I make curl ignore the proxy?

I assume curl is reading the proxy address from the environment variable http_proxy and that the variable should keep its value. Then in a shell like bash, export http_proxy=''; before a command (or in a shell script) would temporarily change its value.

(See curl's manual for all the variables it looks at, under the ENVIRONMENT heading.)

concatenate two database columns into one resultset column

If both Column are numeric Then Use This code

Just Cast Column As Varchar(Size)

Example:

Select (Cast(Col1 as Varchar(20)) + '-' + Cast(Col2 as Varchar(20))) As Col3 from Table

Return positions of a regex match() in Javascript?

In modern browsers, you can accomplish this with string.matchAll().

The benefit to this approach vs RegExp.exec() is that it does not rely on the regex being stateful, as in @Gumbo's answer.

_x000D_
_x000D_
let regexp = /bar/g;
let str = 'foobarfoobar';

let matches = [...str.matchAll(regexp)];
matches.forEach((match) => {
    console.log("match found at " + match.index);
});
_x000D_
_x000D_
_x000D_

Read .csv file in C

A complete example which leaves the fields as NULL-terminated strings in the original input buffer and provides access to them via an array of char pointers. The CSV processor has been confirmed to work with fields enclosed in "double quotes", ignoring any delimiter chars within them.

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

// adjust BUFFER_SIZE to suit longest line 
#define BUFFER_SIZE 1024 * 1024
#define NUM_FIELDS 10
#define MAXERRS 5
#define RET_OK 0
#define RET_FAIL 1
#define FALSE 0
#define TRUE 1

// char* array will point to fields
char *pFields[NUM_FIELDS];
// field offsets into pFields array:
#define LP          0
#define IMIE        1
#define NAZWISKo    2
#define ULICA       3
#define NUMER       4
#define KOD         5
#define MIEJSCOw    6
#define TELEFON     7
#define EMAIL       8
#define DATA_UR     9

long loadFile(FILE *pFile, long *errcount);
static int  loadValues(char *line, long lineno);
static char delim;

long loadFile(FILE *pFile, long *errcount){

    char sInputBuf [BUFFER_SIZE];
    long lineno = 0L;

    if(pFile == NULL)
        return RET_FAIL;

    while (!feof(pFile)) {

        // load line into static buffer
        if(fgets(sInputBuf, BUFFER_SIZE-1, pFile)==NULL)
            break;

        // skip first line (headers)
        if(++lineno==1)
            continue;

        // jump over empty lines
        if(strlen(sInputBuf)==0)
            continue;
        // set pFields array pointers to null-terminated string fields in sInputBuf
        if(loadValues(sInputBuf,lineno)==RET_FAIL){
           (*errcount)++;
            if(*errcount > MAXERRS)
                break;
        } else {    
            // On return pFields array pointers point to loaded fields ready for load into DB or whatever
            // Fields can be accessed via pFields, e.g.
            printf("lp=%s, imie=%s, data_ur=%s\n", pFields[LP], pFields[IMIE], pFields[DATA_UR]);
        }
    }
    return lineno;
}


static int  loadValues(char *line, long lineno){
    if(line == NULL)
        return RET_FAIL;

    // chop of last char of input if it is a CR or LF (e.g.Windows file loading in Unix env.)
    // can be removed if sure fgets has removed both CR and LF from end of line
    if(*(line + strlen(line)-1) == '\r' || *(line + strlen(line)-1) == '\n')
        *(line + strlen(line)-1) = '\0';
    if(*(line + strlen(line)-1) == '\r' || *(line + strlen(line)-1 )== '\n')
        *(line + strlen(line)-1) = '\0';

    char *cptr = line;
    int fld = 0;
    int inquote = FALSE;
    char ch;

    pFields[fld]=cptr;
    while((ch=*cptr) != '\0' && fld < NUM_FIELDS){
        if(ch == '"') {
            if(! inquote)
                pFields[fld]=cptr+1;
            else {
                *cptr = '\0';               // zero out " and jump over it
            }
            inquote = ! inquote;
        } else if(ch == delim && ! inquote){
            *cptr = '\0';                   // end of field, null terminate it
            pFields[++fld]=cptr+1;
        }
        cptr++;
    }   
    if(fld > NUM_FIELDS-1){
        fprintf(stderr, "Expected field count (%d) exceeded on line %ld\n", NUM_FIELDS, lineno);
        return RET_FAIL;
    } else if (fld < NUM_FIELDS-1){
        fprintf(stderr, "Expected field count (%d) not reached on line %ld\n", NUM_FIELDS, lineno);
        return RET_FAIL;    
    }
    return RET_OK;
}

int main(int argc, char **argv)
{
   FILE *fp;
   long errcount = 0L;
   long lines = 0L;

   if(argc!=3){
       printf("Usage: %s csvfilepath delimiter\n", basename(argv[0]));
       return (RET_FAIL);
   }   
   if((delim=argv[2][0])=='\0'){
       fprintf(stderr,"delimiter must be specified\n");
       return (RET_FAIL);
   }
   fp = fopen(argv[1] , "r");
   if(fp == NULL) {
      fprintf(stderr,"Error opening file: %d\n",errno);
      return(RET_FAIL);
   }
   lines=loadFile(fp,&errcount);
   fclose(fp);
   printf("Processed %ld lines, encountered %ld error(s)\n", lines, errcount);
   if(errcount>0)
        return(RET_FAIL);
    return(RET_OK); 
}

PostgreSQL: how to convert from Unix epoch to date?

/* Current time */
 select now(); 

/* Epoch from current time;
   Epoch is number of seconds since 1970-01-01 00:00:00+00 */
 select extract(epoch from now()); 

/* Get back time from epoch */
 -- Option 1 - use to_timestamp function
 select to_timestamp( extract(epoch from now()));
 -- Option 2 - add seconds to 'epoch'
 select timestamp with time zone 'epoch' 
         + extract(epoch from now()) * interval '1 second';

/* Cast timestamp to date */
 -- Based on Option 1
 select to_timestamp(extract(epoch from now()))::date;
 -- Based on Option 2
 select (timestamp with time zone 'epoch' 
          + extract(epoch from now()) * interval '1 second')::date; 

 /* For column epoch_ms */
 select to_timestamp(extract(epoch epoch_ms))::date;

PostgreSQL Docs

How to update Ruby with Homebrew?

Adding to the selected answer (as I haven't enough rep to add comment), one way to see the list of available versions (from ref) try:

$ rbenv install -l

Why isn't textarea an input[type="textarea"]?

I realize this is an older post, but thought this might be helpful to anyone wondering the same question:

While the previous answers are no doubt valid, there is a more simple reason for the distinction between textarea and input.

As mentioned previously, HTML is used to describe and give as much semantic structure to web content as possible, including input forms. A textarea may be used for input, however a textarea can also be marked as read only via the readonly attribute. The existence of such an attribute would not make any sense for an input type, and thus the distinction.

Google Play error "Error while retrieving information from server [DF-DFERH-01]"

Long press on Google play application

  • Select App info
  • Click on Clear Cache
  • Click on Clear app data

Now again click on Google Play app, It will work now.

Set cookies for cross origin requests

For express, upgrade your express library to 4.17.1 which is the latest stable version. Then;

In CorsOption: Set origin to your localhost url or your frontend production url and credentials to true e.g

  const corsOptions = {
    origin: config.get("origin"),
    credentials: true,
  };

I set my origin dynamically using config npm module.

Then , in res.cookie:

For localhost: you do not need to set sameSite and secure option at all, you can set httpOnly to true for http cookie to prevent XSS attack and other useful options depending on your use case.

For production environment, you need to set sameSite to none for cross-origin request and secure to true. Remember sameSite works with express latest version only as at now and latest chrome version only set cookie over https, thus the need for secure option.

Here is how I made mine dynamic

 res
    .cookie("access_token", token, {
      httpOnly: true,
      sameSite: app.get("env") === "development" ? true : "none",
      secure: app.get("env") === "development" ? false : true,
    })

How to check the extension of a filename in a bash script?

You could also do:

   if [ "${FILE##*.}" = "txt" ]; then
       # operation for txt files here
   fi

Correct way to handle conditional styling in React

First, I agree with you as a matter of style - I would also (and do also) conditionally apply classes rather than inline styles. But you can use the same technique:

<div className={{completed ? "completed" : ""}}></div>

For more complex sets of state, accumulate an array of classes and apply them:

var classes = [];

if (completed) classes.push("completed");
if (foo) classes.push("foo");
if (someComplicatedCondition) classes.push("bar");

return <div className={{classes.join(" ")}}></div>;

What is WebKit and how is it related to CSS?

The ultimate question... Is WebKit supported by IE?

Kind of. Check out Chrome Frame, it's a plugin for Internet Explorer that makes it use the Webkit engine. The only quirk is that you have to persuade your visitors to install the plugin.

Update

Chrome Frame is no longer maintained or supported…

Checking if a collection is null or empty in Groovy

FYI this kind of code works (you can find it ugly, it is your right :) ) :

def list = null
list.each { println it }
soSomething()

In other words, this code has null/empty checks both useless:

if (members && !members.empty) {
    members.each { doAnotherThing it }
}

def doAnotherThing(def member) {
  // Some work
}

Replace Div Content onclick

Here's an approach:

HTML:

<div id="1">
    My Content 1
</div>

<div id="2" style="display:none;">
    My Dynamic Content
</div>
<button id="btnClick">Click me!</button>

jQuery:

$('#btnClick').on('click',function(){
    if($('#1').css('display')!='none'){
    $('#2').html('Here is my dynamic content').show().siblings('div').hide();
    }else if($('#2').css('display')!='none'){
        $('#1').show().siblings('div').hide();
    }
});


JsFiddle:
http://jsfiddle.net/ha6qp7w4/
http://jsfiddle.net/ha6qp7w4/4 <--- Commented

How to read from stdin line by line in Node

shareing for others:

read stream line by line,should be good for large files piped into stdin, my version:

var n=0;
function on_line(line,cb)
{
    ////one each line
    console.log(n++,"line ",line);
    return cb();
    ////end of one each line
}

var fs = require('fs');
var readStream = fs.createReadStream('all_titles.txt');
//var readStream = process.stdin;
readStream.pause();
readStream.setEncoding('utf8');

var buffer=[];
readStream.on('data', (chunk) => {
    const newlines=/[\r\n]+/;
    var lines=chunk.split(newlines)
    if(lines.length==1)
    {
        buffer.push(lines[0]);
        return;
    }   

    buffer.push(lines[0]);
    var str=buffer.join('');
    buffer.length=0;
    readStream.pause();

    on_line(str,()=>{
        var i=1,l=lines.length-1;
        i--;
        function while_next()
        {
            i++;
            if(i<l)
            {
                return on_line(lines[i],while_next);
            }
            else
            {
                buffer.push(lines.pop());
                lines.length=0;
                return readStream.resume();
            }
        }
        while_next();
    });
  }).on('end', ()=>{
      if(buffer.length)
          var str=buffer.join('');
          buffer.length=0;
        on_line(str,()=>{
            ////after end
            console.error('done')
            ////end after end
        });
  });
readStream.resume();

How to create empty data frame with column names specified in R?

Just create a data.frame with 0 length variables

eg

nodata <- data.frame(x= numeric(0), y= integer(0), z = character(0))
str(nodata)

## 'data.frame':    0 obs. of  3 variables:
##  $ x: num 
##  $ y: int 
##  $ z: Factor w/ 0 levels: 

or to create a data.frame with 5 columns named a,b,c,d,e

nodata <- as.data.frame(setNames(replicate(5,numeric(0), simplify = F), letters[1:5]))

How to get the first word in the string

You shoud do something like :

print line.split()[0]

Spring Boot application in eclipse, the Tomcat connector configured to listen on port XXXX failed to start

  1. Find the process ID (PID) for the port (e.g.: 8080)

    On Windows:

    netstat -ao | find "8080"
    

    Other Platforms other than windows :

    lsof -i:8080
    
  2. Kill the process ID you found (e.g.: 20712)

    On Windows:

    Taskkill /PID  20712 /F
    

    Other Platforms other than windows :

    kill -9 20712   or kill 20712
    

RegEx to make sure that the string contains at least one lower case char, upper case char, digit and symbol

You can match those three groups separately, and make sure that they all present. Also, [^\w] seems a bit too broad, but if that's what you want you might want to replace it with \W.

Write output to a text file in PowerShell

Use the Out-File cmdlet

 Compare-Object ... | Out-File C:\filename.txt

Optionally, add -Encoding utf8 to Out-File as the default encoding is not really ideal for many uses.

What characters are forbidden in Windows and Linux directory names?

A “comprehensive guide” of forbidden filename characters is not going to work on Windows because it reserves filenames as well as characters. Yes, characters like * " ? and others are forbidden, but there are a infinite number of names composed only of valid characters that are forbidden. For example, spaces and dots are valid filename characters, but names composed only of those characters are forbidden.

Windows does not distinguish between upper-case and lower-case characters, so you cannot create a folder named A if one named a already exists. Worse, seemingly-allowed names like PRN and CON, and many others, are reserved and not allowed. Windows also has several length restrictions; a filename valid in one folder may become invalid if moved to another folder. The rules for naming files and folders are on the Microsoft docs.

You cannot, in general, use user-generated text to create Windows directory names. If you want to allow users to name anything they want, you have to create safe names like A, AB, A2 et al., store user-generated names and their path equivalents in an application data file, and perform path mapping in your application.

If you absolutely must allow user-generated folder names, the only way to tell if they are invalid is to catch exceptions and assume the name is invalid. Even that is fraught with peril, as the exceptions thrown for denied access, offline drives, and out of drive space overlap with those that can be thrown for invalid names. You are opening up one huge can of hurt.

Why is Java's SimpleDateFormat not thread-safe?

Release 3.2 of commons-lang will have FastDateParser class that is a thread-safe substitute of SimpleDateFormat for Gregorian calendar. See LANG-909 for more information.

How to find the path of Flutter SDK

You can use where command in cmd

where flutter

enter image description here

Get random sample from list while maintaining ordering of items?

Simple-to-code O(N + K*log(K)) way

Take a random sample without replacement of the indices, sort the indices, and take them from the original.

indices = random.sample(range(len(myList)), K)
[myList[i] for i in sorted(indices)]

Or more concisely:

[x[1] for x in sorted(random.sample(enumerate(myList),K))]

Optimized O(N)-time, O(1)-auxiliary-space way

You can alternatively use a math trick and iteratively go through myList from left to right, picking numbers with dynamically-changing probability (N-numbersPicked)/(total-numbersVisited). The advantage of this approach is that it's an O(N) algorithm since it doesn't involve sorting!

from __future__ import division

def orderedSampleWithoutReplacement(seq, k):
    if not 0<=k<=len(seq):
        raise ValueError('Required that 0 <= sample_size <= population_size')

    numbersPicked = 0
    for i,number in enumerate(seq):
        prob = (k-numbersPicked)/(len(seq)-i)
        if random.random() < prob:
            yield number
            numbersPicked += 1

Proof of concept and test that probabilities are correct:

Simulated with 1 trillion pseudorandom samples over the course of 5 hours:

>>> Counter(
        tuple(orderedSampleWithoutReplacement([0,1,2,3], 2))
        for _ in range(10**9)
    )
Counter({
    (0, 3): 166680161, 
    (1, 2): 166672608, 
    (0, 2): 166669915, 
    (2, 3): 166667390, 
    (1, 3): 166660630, 
    (0, 1): 166649296
})

Probabilities diverge from true probabilities by less a factor of 1.0001. Running this test again resulted in a different order meaning it isn't biased towards one ordering. Running the test with fewer samples for [0,1,2,3,4], k=3 and [0,1,2,3,4,5], k=4 had similar results.

edit: Not sure why people are voting up wrong comments or afraid to upvote... NO, there is nothing wrong with this method. =)

(Also a useful note from user tegan in the comments: If this is python2, you will want to use xrange, as usual, if you really care about extra space.)

edit: Proof: Considering the uniform distribution (without replacement) of picking a subset of k out of a population seq of size len(seq), we can consider a partition at an arbitrary point i into 'left' (0,1,...,i-1) and 'right' (i,i+1,...,len(seq)). Given that we picked numbersPicked from the left known subset, the remaining must come from the same uniform distribution on the right unknown subset, though the parameters are now different. In particular, the probability that seq[i] contains a chosen element is #remainingToChoose/#remainingToChooseFrom, or (k-numbersPicked)/(len(seq)-i), so we simulate that and recurse on the result. (This must terminate since if #remainingToChoose == #remainingToChooseFrom, then all remaining probabilities are 1.) This is similar to a probability tree that happens to be dynamically generated. Basically you can simulate a uniform probability distribution by conditioning on prior choices (as you grow the probability tree, you pick the probability of the current branch such that it is aposteriori the same as prior leaves, i.e. conditioned on prior choices; this will work because this probability is uniformly exactly N/k).

edit: Timothy Shields mentions Reservoir Sampling, which is the generalization of this method when len(seq) is unknown (such as with a generator expression). Specifically the one noted as "algorithm R" is O(N) and O(1) space if done in-place; it involves taking the first N element and slowly replacing them (a hint at an inductive proof is also given). There are also useful distributed variants and miscellaneous variants of reservoir sampling to be found on the wikipedia page.

edit: Here's another way to code it below in a more semantically obvious manner.

from __future__ import division
import random

def orderedSampleWithoutReplacement(seq, sampleSize):
    totalElems = len(seq)
    if not 0<=sampleSize<=totalElems:
        raise ValueError('Required that 0 <= sample_size <= population_size')

    picksRemaining = sampleSize
    for elemsSeen,element in enumerate(seq):
        elemsRemaining = totalElems - elemsSeen
        prob = picksRemaining/elemsRemaining
        if random.random() < prob:
            yield element
            picksRemaining -= 1

from collections import Counter         
Counter(
    tuple(orderedSampleWithoutReplacement([0,1,2,3], 2))
    for _ in range(10**5)

)

Change url query string value using jQuery

If you only need to modify the page num you can replace it:

var newUrl = location.href.replace("page="+currentPageNum, "page="+newPageNum);

Use VBA to Clear Immediate Window?

I'm in favor of not ever depending on the shortcut keys, as it may work in some languages but not all of them... Here's my humble contribution:

Public Sub CLEAR_IMMEDIATE_WINDOW()
'by Fernando Fernandes
'YouTube: Expresso Excel
'Language: Portuguese/Brazil
    Debug.Print VBA.String(200, vbNewLine)
End Sub

Get the selected value in a dropdown using jQuery.

Hello guys i am using this technique to get the values from the selected dropdown list and it is working like charm.

var methodvalue = $("#method option:selected").val(); 

PyCharm shows unresolved references error for valid code

You might try closing Pycharm, deleting the .idea folder from your project, then starting Pycharm again and recreating the project. This worked for me whereas invalidating cache did not.

Adding dictionaries together, Python

>>> dic0 = {'dic0':0}
>>> dic1 = {'dic1':1}
>>> ndic = dict(dic0.items() + dic1.items())
>>> ndic
{'dic0': 0, 'dic1': 1}
>>>

How to automatically add user account AND password with a Bash script?

From IBM (https://www.ibm.com/support/knowledgecenter/ssw_aix_61/com.ibm.aix.cmds1/chpasswd.htm):

Create a text file, say text.txt and populate it with user:password pairs as follows:

user1:password1
user2:password2
...
usern:passwordn

Save the text.txt file, and run

cat text.txt | chpassword

That's it. The solution is (a) scalable and (b) does not involve printing passwords on the command line.

Showing/Hiding Table Rows with Javascript - can do with ID - how to do with Class?

document.getElementsByClassName returns a NodeList, not a single element, I'd recommend either using jQuery, since you'd only have to use something like $('.new').toggle()

or if you want plain JS try :

function toggle_by_class(cls, on) {
    var lst = document.getElementsByClassName(cls);
    for(var i = 0; i < lst.length; ++i) {
        lst[i].style.display = on ? '' : 'none';
    }
}

How to prevent a background process from being stopped after closing SSH client in Linux

Nohup allows a client process to not be killed if a the parent process is killed, for argument when you logout. Even better still use:

nohup /bin/sh -c "echo \$\$ > $pidfile; exec $FOO_BIN $FOO_CONFIG  " > /dev/null

Nohup makes the process you start immune to termination which your SSH session and its child processes are kill upon you logging out. The command i gave provides you with a way you can store the pid of the application in a pid file so that you can correcly kill it later and allows the process to run after you have logged out.

Conditional Logic on Pandas DataFrame

In this specific example, where the DataFrame is only one column, you can write this elegantly as:

df['desired_output'] = df.le(2.5)

le tests whether elements are less than or equal 2.5, similarly lt for less than, gt and ge.

How to remove tab indent from several lines in IDLE?

For IDLE, select the lines, then open the "Format" menu. (Between "Edit" and "Run" if you're having trouble finding it.) This will also give you the keyboard shortcut, for me it turned out that dedent shortcut was "Ctrl+["

Entity Framework Provider type could not be loaded?

I sorted it out with [DeploymentItem] on my assembly initializing class

namespace MyTests
{
    /// <summary>
    /// Summary description for AssemblyTestInit
    /// </summary>
    [TestClass]
    [DeploymentItem("EntityFramework.SqlServer.dll")]
    public class AssemblyTestInit
    {
        public AssemblyTestInit()
        {
        }

        private TestContext testContextInstance;

        public TestContext TestContext
        {
            get
            {
                return testContextInstance;
            }
            set
            {
                testContextInstance = value;
            }
        }

        [AssemblyInitialize()]
        public static void DbContextInitialize(TestContext testContext)
        {
            Database.SetInitializer<TestContext>(new TestContextInitializer());
        }
    }
}

Junit test case for database insert method with DAO and web service

@Test
public void testSearchManagementStaff() throws SQLException
{
    boolean res=true;
    ManagementDaoImp mdi=new ManagementDaoImp();
    boolean b=mdi.searchManagementStaff("[email protected]"," 123456");
    assertEquals(res,b);
}

What is the App_Data folder used for in Visual Studio?

We use it as a temporary storage area for uploaded csv files. Once uploaded, an ajax method processes and deletes the file.

Place a button right aligned

If the button is the only element on the block:

_x000D_
_x000D_
.border {_x000D_
  border: 2px blue dashed;_x000D_
}_x000D_
_x000D_
.mr-0 {_x000D_
  margin-right: 0;_x000D_
}_x000D_
.ml-auto {_x000D_
  margin-left:auto;_x000D_
}_x000D_
.d-block {_x000D_
  display:block;_x000D_
}
_x000D_
<p class="border">_x000D_
  <input type="button" class="d-block mr-0 ml-auto" value="The Button">_x000D_
</p>
_x000D_
_x000D_
_x000D_

If there are other elements on the block:

_x000D_
_x000D_
.border {_x000D_
  border: 2px indigo dashed;_x000D_
}_x000D_
_x000D_
.d-table {_x000D_
  display:table;_x000D_
}_x000D_
_x000D_
.d-table-cell {_x000D_
  display:table-cell;_x000D_
}_x000D_
_x000D_
.w-100 {_x000D_
  width: 100%;_x000D_
}_x000D_
_x000D_
.tar {_x000D_
  text-align: right;_x000D_
}
_x000D_
<div class="border d-table w-100">_x000D_
  <p class="d-table-cell">The paragraph.....lorem ipsum...etc.</p>_x000D_
  <div class="d-table-cell tar">_x000D_
    <button >The Button</button>_x000D_
  </div>_x000D_
</div>
_x000D_
_x000D_
_x000D_

With flex-box:

_x000D_
_x000D_
.flex-box {_x000D_
  display:flex;_x000D_
  justify-content:space-between;_x000D_
  outline: 2px dashed blue;_x000D_
}_x000D_
_x000D_
.flex-box-2 {_x000D_
  display:flex;_x000D_
  justify-content: flex-end;_x000D_
  outline: 2px deeppink dashed;_x000D_
}
_x000D_
<h1>Button with Text</h1>_x000D_
<div class="flex-box">_x000D_
<p>Once upon a time in a ...</p>_x000D_
<button>Read More...</button>_x000D_
</div>_x000D_
_x000D_
<h1>Only Button</h1>_x000D_
<div class="flex-box-2">_x000D_
  <button>The Button</button>_x000D_
</div>_x000D_
_x000D_
<h1>Multiple Buttons</h1>_x000D_
<div class="flex-box-2">_x000D_
  <button>Button 1</button>_x000D_
  <button>Button 2</button>_x000D_
</div>
_x000D_
_x000D_
_x000D_

Good Luck...

Changing plot scale by a factor in matplotlib

Instead of changing the ticks, why not change the units instead? Make a separate array X of x-values whose units are in nm. This way, when you plot the data it is already in the correct format! Just make sure you add a xlabel to indicate the units (which should always be done anyways).

from pylab import *

# Generate random test data in your range
N = 200
epsilon = 10**(-9.0)
X = epsilon*(50*random(N) + 1)
Y = random(N)

# X2 now has the "units" of nanometers by scaling X
X2 = (1/epsilon) * X

subplot(121)
scatter(X,Y)
xlim(epsilon,50*epsilon)
xlabel("meters")

subplot(122)
scatter(X2,Y)
xlim(1, 50)
xlabel("nanometers")

show()

enter image description here

How to run Conda?

It turns out that I had not set the path.

To do so, I first had to edit .bash_profile (I downloaded it to my local desktop to do that, I do not know how to text edit a file from linux)

Then add this to .bash_profile:

PATH=$PATH:$HOME/anaconda/bin

Consider defining a bean of type 'service' in your configuration [Spring boot]

You are trying to inject a bean in itself. That's obviously not going to work.

TopicServiceImplementation implements TopicService. That class attempts to autowire (by field!) a `TopicService. So you're essentially asking the context to inject itself.

It looks like you've edited the content of the error message: Field topicService in seconds47.restAPI.topics is not a class. Please be careful if you need to hide sensitive information as it makes it much harder for others to help you.

Back on the actual issue, it looks like injecting TopicService in itself is a glitch on your side.

What is the correct value for the disabled attribute?

In HTML5, there is no correct value, all the major browsers do not really care what the attribute is, they are just checking if the attribute exists so the element is disabled.

Best way to create an empty map in Java

Either Collections.emptyMap(), or if type inference doesn't work in your case,
Collections.<String, String>emptyMap()