Programs & Examples On #Idispatch

How to permanently set $PATH on Linux/Unix?

Add to /etc/profile.d folder script [name_of_script].sh with line: export PATH=$PATH:/dir. Every script within /etc/profile.d folder is automaticaly executed by /etc/profile on login.

How to validate email id in angularJs using ng-pattern

Use below regular expression

^[_\.0-9a-z-]+@([0-9a-z][0-9a-z-]+)+((\.)[a-z]{2,})+$

It allows

[email protected]
[email protected]
[email protected]
[email protected]
[email protected]

Converting HTML to PDF using PHP?

If you wish to create a pdf from php, pdflib will help you (as some others suggested).

Else, if you want to convert an HTML page to PDF via PHP, you'll find a little trouble outta here.. For 3 years I've been trying to do it as best as I can.

So, the options I know are:

DOMPDF : php class that wraps the html and builds the pdf. Works good, customizable (if you know php), based on pdflib, if I remember right it takes even some CSS. Bad news: slow when the html is big or complex.

HTML2PS: same as DOMPDF, but this one converts first to a .ps (ghostscript) file, then, to whatever format you need (pdf, jpg, png). For me is little better than dompdf, but has the same speed problem.. but, better compatibility with CSS.

Those two are php classes, but if you can install some software on the server, and access it throught passthru() or system(), give a look to these too:

wkhtmltopdf: based on webkit (safari's wrapper), is really fast and powerful.. seems like this is the best one (atm) for converting html pages to pdf on the fly; taking only 2 seconds for a 3 page xHTML document with CSS2. It is a recent project, anyway, the google.code page is often updated.

htmldoc : This one is a tank, it never really stops/crashes.. the project looks dead since 2007, but anyway if you don't need CSS compatibility this can be nice for you.

Laravel Migration Change to Make a Column Nullable

Adding to Dmitri Chebotarev's answer, as for Laravel 5+.

After requiring the doctrine/dbal package:

composer require doctrine/dbal

You can then make a migration with nullable columns, like so:

public function up()
{
    Schema::table('users', function (Blueprint $table) {
        // change() tells the Schema builder that we are altering a table
        $table->integer('user_id')->unsigned()->nullable()->change();
    });
}

To revert the operation, do:

public function down()
{
    /* turn off foreign key checks for a moment */
    DB::statement('SET FOREIGN_KEY_CHECKS = 0');
    /* set null values to 0 first */
    DB::statement('UPDATE `users` SET `user_id` = 0 WHERE `user_id` IS NULL;');
    /* alter table */
    DB::statement('ALTER TABLE `users` MODIFY `user_id` INTEGER UNSIGNED NOT NULL;');
    /* finally turn foreign key checks back on */
    DB::statement('SET FOREIGN_KEY_CHECKS = 1');
}

Good PHP ORM Library?

A really good simple ORM is MyActiveRecord. MyActiveRecord documentation. I have been using it a lot and can say it's very simple and well tested.

Getting time elapsed in Objective-C

Use the timeIntervalSinceDate method

NSTimeInterval secondsElapsed = [secondDate timeIntervalSinceDate:firstDate];

NSTimeInterval is just a double, define in NSDate like this:

typedef double NSTimeInterval;

Setting and getting localStorage with jQuery

You said you are attempting to get the text from a div and store it on local storage.

Please Note: Text and Html are different. In the question you mentioned text. html() will return Html content like <a>example</a>. if you want to get Text content then you have to use text() instead of html() then the result will be example instead of <a>example<a>. Anyway, I am using your terminology let it be Text.

Step 1: get the text from div.

what you did is not get the text from div but set the text to a div.

$('#test').html("Test"); 

is actually setting text to div and the output will be a jQuery object. That is why it sets it as [object Object].

To get the text you have to write like this
$('#test').html();

This will return a string not an object so the result will be Test in your case.

Step 2: set it to local storage.

Your approach is correct and you can write it as

localStorage.key=value

But the preferred approach is

localStorage.setItem(key,value); to set

localStorage.getItem(key); to get.

key and value must be strings.

so in your context code will become

$('#test').html("Test");
localStorage.content = $('#test').html();
$('#test').html(localStorage.content);

But I don't find any meaning in your code. Because you want to get the text from div and store it on local storage. And again you are reading the same from local storage and set to div. just like a=10; b=a; a=b;

If you are facing any other problems please update your question accordingly.

How to read large text file on windows?

If all you need is a tool for reading, then this thing will open the file instantly http://www.readfileonline.com/

CSS last-child selector: select last-element of specific class, not last child inside of parent?

:last-child only works when the element in question is the last child of the container, not the last of a specific type of element. For that, you want :last-of-type

http://jsfiddle.net/C23g6/3/

As per @BoltClock's comment, this is only checking for the last article element, not the last element with the class of .comment.

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_x000D_
body {_x000D_
  background: black;_x000D_
}_x000D_
_x000D_
.comment {_x000D_
  width: 470px;_x000D_
  border-bottom: 1px dotted #f0f0f0;_x000D_
  margin-bottom: 10px;_x000D_
}_x000D_
_x000D_
.comment:last-of-type {_x000D_
  border-bottom: none;_x000D_
  margin-bottom: 0;_x000D_
}
_x000D_
<div class="commentList">_x000D_
  <article class="comment " id="com21"></article>_x000D_
_x000D_
  <article class="comment " id="com20"></article>_x000D_
_x000D_
  <article class="comment " id="com19"></article>_x000D_
_x000D_
  <div class="something"> hello </div>_x000D_
</div>
_x000D_
_x000D_
_x000D_

How do I perform a JAVA callback between classes?

I don't know if this is what you are looking for, but you can achieve this by passing a callback to the child class.

first define a generic callback:

public interface ITypedCallback<T> {
    void execute(T type);
}

create a new ITypedCallback instance on ServerConnections instantiation:

public Server(int _address) {
    serverConnectionHandler = new ServerConnections(new ITypedCallback<Socket>() {
        @Override
        public void execute(Socket socket) {
            // do something with your socket here
        }
    });
}

call the execute methode on the callback object.

public class ServerConnections implements Runnable {

    private ITypedCallback<Socket> callback;

    public ServerConnections(ITypedCallback<Socket> _callback) {
        callback = _callback;
    }

    @Override
    public void run() {   
        try {
            mainSocket = new ServerSocket(serverPort);
            while (true) {
                callback.execute(mainSocket.accept());
            }
        } catch (IOException ex) {
            Logger.getLogger(Server.class.getName()).log(Level.SEVERE, null, ex);
        }
    }
}

btw: I didn't check if it's 100% correct, directly coded it here.

How to add an ORDER BY clause using CodeIgniter's Active Record methods?

function getProductionGroupItems($itemId){
     $this->db->select("*");
     $this->db->where("id",$itemId);
     $this->db->or_where("parent_item_id",$itemId);

    /*********** order by *********** */
     $this->db->order_by("id", "asc");

     $q=$this->db->get("recipe_products");
     if($q->num_rows()>0){
         foreach($q->result() as $row){
             $data[]=$row;
         }
         return $data;
     }
    return false;
}

Android button with different background colors

You have to put the selector.xml file in the drwable folder. Then write: android:background="@drawable/selector". This takes care of the pressed and focussed states.

How do I programmatically determine operating system in Java?

You can use:

System.getProperty("os.name")

P.S. You may find this code useful:

class ShowProperties {
    public static void main(String[] args) {
        System.getProperties().list(System.out);
    }
}

All it does is print out all the properties provided by your Java implementations. It'll give you an idea of what you can find out about your Java environment via properties. :-)

Stopping fixed position scrolling at a certain point?

I liked this solution

$(window).scroll(function(){
    $("#theFixed").css("margin-top",Math.max(-250,0-$(this).scrollTop()));
});

my problem was that I had to deal with a position relative container in Adobe Muse.

My solution:

$(window).scroll(function(){
    if($(this).scrollTop()>425) {
         $("#theRelative").css("margin-top",$(this).scrollTop()-425);
    }
});

How to set CATALINA_HOME variable in windows 7?

In order to set CATALINA_HOME:

  1. First, unzip and paste the apache-tomcat-7.1.100 folder in your C:// drive folder.

NOTE: Do not place your apache tomcat folder within any other folder or drive, place it directly in C:// drive folder only. (I did this mistake and none of the above-mentioned solutions were working).

  1. Open environment variable dialog box (windows key+ pause-break key --> advanced setting).

  2. Add a new variable name as "CATALINA_HOME" and add the variable path as "C://apache-tomcat-7.1.100"(as in my case), in System Variables.

  3. Edit PATH variable name add "%CATALINA_HOME%\bin" and press OK.

  4. Close the window and it will be saved.

  5. Open Command Prompt window and type command- "%CATALINA_HOME%\bin\startup.bat" to run and start the Tomcat server.

  6. END!

Disable password authentication for SSH

I followed these steps (for Mac).

In /etc/ssh/sshd_config change

#ChallengeResponseAuthentication yes
#PasswordAuthentication yes

to

ChallengeResponseAuthentication no
PasswordAuthentication no

Now generate the RSA key:

ssh-keygen -t rsa -P '' -f ~/.ssh/id_rsa

(For me an RSA key worked. A DSA key did not work.)

A private key will be generated in ~/.ssh/id_rsa along with ~/.ssh/id_rsa.pub (public key).

Now move to the .ssh folder: cd ~/.ssh

Enter rm -rf authorized_keys (sometimes multiple keys lead to an error).

Enter vi authorized_keys

Enter :wq to save this empty file

Enter cat ~/.ssh/id_rsa.pub >> ~/.ssh/authorized_keys

Restart the SSH:

sudo launchctl stop com.openssh.sshd
sudo launchctl start com.openssh.sshd

How to add the JDBC mysql driver to an Eclipse project?

if you are getting this exception again and again then download my-sql connector and paste in tomcat/WEB-INF/lib folder...note that some times WEB-INF folder does not contains lib folder, at that time manually create lib folder and paste mysql connector in that folder..definitely this will work.if still you got problem then check that your jdk must match your system. i.e if your system is 64 bit then jdk must be 64 bit

RecyclerView vs. ListView

There are many differences between ListView and RecyclerView, but you should be aware of the following in particular:

  • The ViewHolder pattern is entirely optional in ListView, but it’s baked into RecyclerView.
  • ListView only supports vertical scrolling, but RecyclerView isn’t limited to vertically scrolling lists.

Check if a file exists in jenkins pipeline

You need to use brackets when using the fileExists step in an if condition or assign the returned value to a variable

Using variable:

def exists = fileExists 'file'

if (exists) {
    echo 'Yes'
} else {
    echo 'No'
}

Using brackets:

if (fileExists('file')) {
    echo 'Yes'
} else {
    echo 'No'
}

What is the difference between const int*, const int * const, and int const *?

I had the same doubt as you until I came across this book by the C++ Guru Scott Meyers. Refer the third Item in this book where he talks in details about using const.

Just follow this advice

  1. If the word const appears to the left of the asterisk, what's pointed to is constant
  2. If the word const appears to the right of the asterisk, the pointer itself is constant
  3. If const appears on both sides, both are constant

Cannot find "Package Explorer" view in Eclipse

For Eclipse version 4.3.0.v20130605-2000. You can use the Java (default) perspective. In this perspective, it provides the Package Explorer view.

To use the Java (default) perspective: Window -> Open Perspective -> Other... -> Java (default) -> Ok

If you already use the Java (default) perspective but accidentally close the Package Explorer view, you can open it by; Window -> Show View -> Package Explorer (Alt+Shift+Q,P)

If the Package Explorer still doesn't appear in the Java (default) perspective, I suggest you to right-click on the Java (default) perspective button that is located in the top-right of the Eclipse IDE and then select Reset. The Java (default) perspective will show the Package Explorer view, Code pane, Outline view, Problems, JavaDoc and Declaration View.

How do I serialize a Python dictionary into a string, and then back to a dictionary?

If you are trying to only serialize then pprint may also be a good option. It requires the object to be serialized and a file stream.

Here's some code:

from pprint import pprint
my_dict = {1:'a',2:'b'}
with open('test_results.txt','wb') as f:
    pprint(my_dict,f)

I am not sure if we can deserialize easily. I was using json to serialize and deserialze earlier which works correctly in most cases.

f.write(json.dumps(my_dict, sort_keys = True, indent = 2, ensure_ascii=True))

However, in one particular case, there were some errors writing non-unicode data to json.

Return a string method in C#

Use x.fullNameMethod() to call the method.

ssh "permissions are too open" error

In my case, I was trying to connect from the Ubuntu app in Windows 10 and got the error above. It could be resolved without any permission changes by running sudo su in the Ubuntu console prior to the actual command

Get loop counter/index using for…of syntax in JavaScript

Solution for small array collections:

for (var obj in arr) {
    var i = Object.keys(arr).indexOf(obj);
}

arr - ARRAY, obj - KEY of current element, i - COUNTER/INDEX

Notice: Method keys() is not available for IE version <9, you should use Polyfill code. https://developer.mozilla.org/en/docs/Web/JavaScript/Reference/Global_Objects/Object/keys

html5 audio player - jquery toggle click play/pause?

You can call native methods trough trigger in jQuery. Just do this:

$('.play').trigger("play");

And the same for pause: $('.play').trigger("pause");

EDIT: as F... pointed out in the comments, you can do something similar to access properties: $('.play').prop("paused");

What does "for" attribute do in HTML <label> tag?

Using label for= in html form

This could permit to visualy dissociate label(s) and object while keeping them linked.

Sample: there is a checkbox and two labels. You could check/uncheck the box by clicking indifferently on any label or on box, but not on text nor on input content...

_x000D_
_x000D_
<label for="demo1"> There is a label </label>
<br />
Lorem ipsum dolor sit amet, consectetuer adipiscing elit. Duis sem velit, ultrices et, fermentum auctor, rhoncus ut, ligula. Phasellus at purus sed purus cursus iaculis. Suspendisse fermentum. Pellentesque et arcu. Maecenas viverra. In consectetuer, lorem eu lobortis egestas, velit odio imperdiet eros, sit amet sagittis nunc mi ac neque. Sed non ipsum. Nullam venenatis gravida orci.
<br />
<label for="demo1"> There is a 2nd label </label>
<input id="demo1" type="checkbox">Demo 1</input>
_x000D_
_x000D_
_x000D_

Some useful tricks

By use stylesheet CSS power, you could do a lot of interresting things...

_x000D_
_x000D_
#demo2:checked ~ .but2:before { content: 'Des'; }
#demo2:checked ~ .box2:before { content: '?'; }
.but2:before { content: 'S'; }
.box2:before { content: '?'; }
#demo1:checked ~ .but1:before { content: 'Des'; }
#demo1:checked ~ .box1:before { content: '?'; }
.but1:before { content: 'S'; }
.box1:before { content: '?'; }
_x000D_
<input id="demo1" type="checkbox">Demo 1</input>
<input id="demo2" type="checkbox">Demo 2</input>
<br />
<label for="demo1" class="but1">elect 2</label> - 
<label for="demo2" class="but2">elect 1</label>
<br />
Lorem ipsum dolor sit amet, consectetuer adipiscing elit. Duis sem velit, ultrices et, fermentum auctor, rhoncus ut, ligula. Phasellus at purus sed purus cursus iaculis. Suspendisse fermentum. Pellentesque et arcu. Maecenas viverra. In consectetuer, lorem eu lobortis egestas, velit odio imperdiet eros, sit amet sagittis nunc mi ac neque. Sed non ipsum. Nullam venenatis gravida orci.
<br />
<label for="demo1" class="but1">elect this 2nd label </label> - 
<label class="but2" for="demo2">elect this another 2nd label </label>
<br />
<label for="demo1" class="box1"> check 1</label>
<label for="demo2" class="box2"> check 2</label> 
_x000D_
_x000D_
_x000D_

Get Selected Item Using Checkbox in Listview

Assuming you want to get items of row whose check boxes are checked at the click of a button. Assumption based on your title "Get Selected Item Using Checkbox in Listview when I click a Button".

Try the below. Make only changes as below. Keep the rest the same.

Explanation and discussion on the topic @

https://groups.google.com/forum/?fromgroups#!topic/android-developers/No0LrgJ6q2M

MainActivity.java

public class MainActivity extends Activity {
     AppInfoAdapter adapter ;
     AppInfo app_info[] ;
        @Override
        protected void onCreate(Bundle savedInstanceState){
            super.onCreate(savedInstanceState);
            setContentView(R.layout.activity_main);


            final ListView listApplication = (ListView)findViewById(R.id.listApplication);
            Button b= (Button) findViewById(R.id.button1);
            b.setOnClickListener(new OnClickListener()
            {

                @Override
                public void onClick(View v) {
                    // TODO Auto-generated method stub

                    StringBuilder result = new StringBuilder();
                    for(int i=0;i<adapter.mCheckStates.size();i++)
                    {
                        if(adapter.mCheckStates.get(i)==true)
                        {

                                           result.append(app_info[i].applicationName);
                            result.append("\n");
                        }

                    }
                    Toast.makeText(MainActivity.this, result, 1000).show();
                }

            });

            ApplicationInfo applicationInfo = getApplicationInfo();
            PackageManager pm = getPackageManager();
            List<PackageInfo> pInfo = new ArrayList<PackageInfo>();
            pInfo.addAll(pm.getInstalledPackages(0));
            app_info = new AppInfo[pInfo.size()];

            int counter = 0;
            for(PackageInfo item: pInfo){
                try{

                    applicationInfo = pm.getApplicationInfo(item.packageName, 1);

                    app_info[counter] = new AppInfo(pm.getApplicationIcon(applicationInfo), 
                            String.valueOf(pm.getApplicationLabel(applicationInfo)));

                    System.out.println(counter);

                }
                catch(Exception e){
                     System.out.println(e.getMessage());
                }

                counter++;
            }

           adapter = new AppInfoAdapter(this, R.layout.listview_item_row, app_info);
            listApplication.setAdapter(adapter);

        }
}

activity_main.xml ListView with button at the buton

<RelativeLayout xmlns:android="http://schemas.android.com/apk/res/android"
    xmlns:tools="http://schemas.android.com/tools"
    android:layout_width="match_parent"
    android:layout_height="match_parent"
    android:paddingBottom="@dimen/activity_vertical_margin"
    android:paddingLeft="@dimen/activity_horizontal_margin"
    android:paddingRight="@dimen/activity_horizontal_margin"
    android:paddingTop="@dimen/activity_vertical_margin"
    tools:context=".MainActivity" >

    <ListView
        android:layout_width="fill_parent"
        android:id="@+id/listApplication"
        android:layout_height="fill_parent"
        android:layout_above="@+id/button1"
        android:text="@string/hello_world" />

    <Button
        android:id="@+id/button1"
        android:layout_width="wrap_content"
        android:layout_height="wrap_content"
        android:layout_alignParentBottom="true"
        android:layout_centerHorizontal="true"
        android:text="Button" />

</RelativeLayout>

AppInfoAdapter

public class AppInfoAdapter extends ArrayAdapter<AppInfo> implements CompoundButton.OnCheckedChangeListener
{  SparseBooleanArray mCheckStates; 

    Context context;
    int layoutResourceId;
    AppInfo  data[] = null;

    public AppInfoAdapter(Context context, int layoutResourceId, AppInfo[] data){
        super(context, layoutResourceId,data);
        this.layoutResourceId = layoutResourceId;
        this.context = context;
        this.data = data;
        mCheckStates = new SparseBooleanArray(data.length);
    }

    @Override
    public View getView(int position, View convertView, ViewGroup parent){

        View row = convertView;
        AppInfoHolder holder= null;

        if (row == null){

            LayoutInflater inflater = ((Activity)context).getLayoutInflater();
            row = inflater.inflate(layoutResourceId, parent, false);

            holder = new AppInfoHolder();

            holder.imgIcon = (ImageView) row.findViewById(R.id.imageView1);
            holder.txtTitle = (TextView) row.findViewById(R.id.textView1);
            holder.chkSelect = (CheckBox) row.findViewById(R.id.checkBox1);

            row.setTag(holder);

        }
        else{
            holder = (AppInfoHolder)row.getTag();
        }


        AppInfo appinfo = data[position];
        holder.txtTitle.setText(appinfo.applicationName);
        holder.imgIcon.setImageDrawable(appinfo.icon);
       // holder.chkSelect.setChecked(true);
        holder.chkSelect.setTag(position);
        holder.chkSelect.setChecked(mCheckStates.get(position, false));
        holder.chkSelect.setOnCheckedChangeListener(this);
        return row;

    }
    public boolean isChecked(int position) {
        return mCheckStates.get(position, false);
    }

    public void setChecked(int position, boolean isChecked) {
        mCheckStates.put(position, isChecked);

    }

    public void toggle(int position) {
        setChecked(position, !isChecked(position));

    }
@Override
public void onCheckedChanged(CompoundButton buttonView,
        boolean isChecked) {

     mCheckStates.put((Integer) buttonView.getTag(), isChecked);    

}
static class AppInfoHolder
{
    ImageView imgIcon;
    TextView txtTitle;
    CheckBox chkSelect;

}
}

Here's the snap shot

enter image description here

How to POST a FORM from HTML to ASPX page

You sure can. Create an HTML page with the form in it that will contain the necessary components from the login.aspx page (i.e. username, etc), and make sure they have the same IDs. For you action, make sure it's a post.

You might have to do some code on the login.aspx page in the Page_Load function to read the form (in the Request.Form object) and call the appropriate functions to log the user in, but other than that, you should have access to the form, and can do what you want with it.

Passing variables through handlebars partial

This can also be done in later versions of handlebars using the key=value notation:

 {{> mypartial foo='bar' }}

Allowing you to pass specific values to your partial context.

Reference: Context different for partial #182

How do I configure the proxy settings so that Eclipse can download new plugins?

Just to add to the thread as a POSSIBLE solution, I faced a similar issue when developing on a Linux system that was behind a company firewall. However, using a Windows XP machine, Eclipse was able to access different update sites just fine as both the manual and native network connection providers worked just fine using the company proxy.

After stumbling around for some time, I came across a discussion about using NTLMv2 and an implementation to be found at http://cntlm.sourceforge.net/. To whomever posted this, I give much credit to as it helped me get past the issue running on Linux. As a side note, I was using Eclipse 3.6.2 / Helios on both the Linux and Windows distros.

Best of luck on finding a solution!

What is the meaning of the word logits in TensorFlow?

The logit (/'lo?d??t/ LOH-jit) function is the inverse of the sigmoidal "logistic" function or logistic transform used in mathematics, especially in statistics. When the function's variable represents a probability p, the logit function gives the log-odds, or the logarithm of the odds p/(1 - p).

See here: https://en.wikipedia.org/wiki/Logit

npm - EPERM: operation not permitted on Windows

I solved the problem by changing windows user access for the project folder:

Here is a screenshot: http://prntscr.com/djdn0g

enter image description here

Re-render React component when prop changes

I would recommend having a look at this answer of mine, and see if it is relevant to what you are doing. If I understand your real problem, it's that your just not using your async action correctly and updating the redux "store", which will automatically update your component with it's new props.

This section of your code:

componentDidMount() {
      if (this.props.isManager) {
        this.props.dispatch(actions.fetchAllSites())
      } else {
        const currentUserId = this.props.user.get('id')
        this.props.dispatch(actions.fetchUsersSites(currentUserId))
      }  
    }

Should not be triggering in a component, it should be handled after executing your first request.

Have a look at this example from redux-thunk:

function makeASandwichWithSecretSauce(forPerson) {

  // Invert control!
  // Return a function that accepts `dispatch` so we can dispatch later.
  // Thunk middleware knows how to turn thunk async actions into actions.

  return function (dispatch) {
    return fetchSecretSauce().then(
      sauce => dispatch(makeASandwich(forPerson, sauce)),
      error => dispatch(apologize('The Sandwich Shop', forPerson, error))
    );
  };
}

You don't necessarily have to use redux-thunk, but it will help you reason about scenarios like this and write code to match.

Restoring MySQL database from physical files

Yes it is! Just add them to your database-folder ( depending on the OS ) and run a command such as "MySQL Fix Permissions". This re-stored the database. See too it that the correct permissions are set on the files aswell.

Sort a list of lists with a custom compare function

Since the OP was asking for using a custom compare function (and this is what led me to this question as well), I want to give a solid answer here:

Generally, you want to use the built-in sorted() function which takes a custom comparator as its parameter. We need to pay attention to the fact that in Python 3 the parameter name and semantics have changed.

How the custom comparator works

When providing a custom comparator, it should generally return an integer/float value that follows the following pattern (as with most other programming languages and frameworks):

  • return a negative value (< 0) when the left item should be sorted before the right item
  • return a positive value (> 0) when the left item should be sorted after the right item
  • return 0 when both the left and the right item have the same weight and should be ordered "equally" without precedence

In the particular case of the OP's question, the following custom compare function can be used:

def compare(item1, item2):
    return fitness(item1) - fitness(item2)

Using the minus operation is a nifty trick because it yields to positive values when the weight of left item1 is bigger than the weight of the right item2. Hence item1 will be sorted after item2.

If you want to reverse the sort order, simply reverse the subtraction: return fitness(item2) - fitness(item1)

Calling sorted() in Python 2

sorted(mylist, cmp=compare)

or:

sorted(mylist, cmp=lambda item1, item2: fitness(item1) - fitness(item2))

Calling sorted() in Python 3

from functools import cmp_to_key
sorted(mylist, key=cmp_to_key(compare))

or:

from functools import cmp_to_key
sorted(mylist, key=cmp_to_key(lambda item1, item2: fitness(item1) - fitness(item2)))

Number of elements in a javascript object

To do this in any ES5-compatible environment

Object.keys(obj).length

(Browser support from here)
(Doc on Object.keys here, includes method you can add to non-ECMA5 browsers)

MySQL my.cnf file - Found option without preceding group

it is because of letters or digit infront of [mysqld] just check the leeters or digit anything is not required before [mysqld]

it may be something like

0[mysqld] then this error will occur

window.open(url, '_blank'); not working on iMac/Safari

You can't rely on window.open because browsers may have different policies. I had the same issue and I used the code below instead.

let a = document.createElement("a");
document.body.appendChild(a);
a.style = "display: none";
a.href = <your_url>;
a.download = <your_fileName>;
a.click();
document.body.removeChild(a);

How to split strings into text and number?

I would approach this by using re.match in the following way:

import re
match = re.match(r"([a-z]+)([0-9]+)", 'foofo21', re.I)
if match:
    items = match.groups()
print(items)
>> ("foofo", "21")

Add timestamp column with default NOW() for new rows only

For example, I will create a table called users as below and give a column named date a default value NOW()

create table users_parent (
    user_id     varchar(50),
    full_name   varchar(240),
    login_id_1  varchar(50),
    date        timestamp NOT NULL DEFAULT NOW()
);

Thanks

ViewDidAppear is not called when opening app from background

Just have your view controller register for the UIApplicationWillEnterForegroundNotification notification and react accordingly.

Where to declare variable in react js

Using ES6 syntax in React does not bind this to user-defined functions however it will bind this to the component lifecycle methods.

So the function that you declared will not have the same context as the class and trying to access this will not give you what you are expecting.

For getting the context of class you have to bind the context of class to the function or use arrow functions.

Method 1 to bind the context:

class MyContainer extends Component {

    constructor(props) {
        super(props);
        this.onMove = this.onMove.bind(this);
        this.testVarible= "this is a test";
    }

    onMove() {
        console.log(this.testVarible);
    }
}

Method 2 to bind the context:

class MyContainer extends Component {

    constructor(props) {
        super(props);
        this.testVarible= "this is a test";
    }

    onMove = () => {
        console.log(this.testVarible);
    }
}

Method 2 is my preferred way but you are free to choose your own.

Update: You can also create the properties on class without constructor:

class MyContainer extends Component {

    testVarible= "this is a test";

    onMove = () => {
        console.log(this.testVarible);
    }
}

Note If you want to update the view as well, you should use state and setState method when you set or change the value.

Example:

class MyContainer extends Component {

    state = { testVarible: "this is a test" };

    onMove = () => {
        console.log(this.state.testVarible);
        this.setState({ testVarible: "new value" });
    }
}

Check if an element contains a class in JavaScript?

Here is a little snippet If you’re trying to check wether element contains a class, without using jQuery.

function hasClass(element, className) {
    return element.className && new RegExp("(^|\\s)" + className + "(\\s|$)").test(element.className);
}

This accounts for the fact that element might contain multiple class names separated by space.

OR


You can also assign this function to element prototype.

Element.prototype.hasClass = function(className) {
    return this.className && new RegExp("(^|\\s)" + className + "(\\s|$)").test(this.className);
};

And trigger it like this (very similar to jQuery’s .hasClass() function):

document.getElementById('MyDiv').hasClass('active');

Make a phone call programmatically

Swift 3

let phoneNumber: String = "tel://3124235234"
UIApplication.shared.openURL(URL(string: phoneNumber)!)

How can I use pointers in Java?

Java does not have pointers like C has, but it does allow you to create new objects on the heap which are "referenced" by variables. The lack of pointers is to stop Java programs from referencing memory locations illegally, and also enables Garbage Collection to be automatically carried out by the Java Virtual Machine.

CSS Font "Helvetica Neue"

This font is not standard on all devices. It is installed by default on some Macs, but rarely on PCs and mobile devices.

To use this font on all devices, use a @font-face declaration in your CSS to link to it on your domain if you wish to use it.

@font-face { font-family: Delicious; src: url('Delicious-Roman.otf'); } 
@font-face { font-family: Delicious; font-weight: bold; src: url('Delicious-Bold.otf'); }

Taken from css3.info

JavaScript regex for alphanumeric string with length of 3-5 chars

You'd have to define alphanumerics exactly, but

/^(\w{3,5})$/ 

Should match any digit/character/_ combination of length 3-5.

If you also need the dash, make sure to escape it (\-) add it, like this: :

/^([\w\-]{3,5})$/ 

Also: the ^ anchor means that the sequence has to start at the beginning of the line (character string), and the $ that it ends at the end of the line (character string). So your value string mustn't contain anything else, or it won't match.

Multiprocessing vs Threading Python

Other answers have focused more on the multithreading vs multiprocessing aspect, but in python Global Interpreter Lock (GIL) has to be taken into account. When more number (say k) of threads are created, generally they will not increase the performance by k times, as it will still be running as a single threaded application. GIL is a global lock which locks everything out and allows only single thread execution utilizing only a single core. The performance does increase in places where C extensions like numpy, Network, I/O are being used, where a lot of background work is done and GIL is released.
So when threading is used, there is only a single operating system level thread while python creates pseudo-threads which are completely managed by threading itself but are essentially running as a single process. Preemption takes place between these pseudo threads. If the CPU runs at maximum capacity, you may want to switch to multiprocessing.
Now in case of self-contained instances of execution, you can instead opt for pool. But in case of overlapping data, where you may want processes communicating you should use multiprocessing.Process.

how to exit a python script in an if statement

This works fine for me:

while True:
   answer = input('Do you want to continue?:')
   if answer.lower().startswith("y"):
      print("ok, carry on then")
   elif answer.lower().startswith("n"):
      print("sayonara, Robocop")
      exit()

edit: use input in python 3.2 instead of raw_input

How to perform Join between multiple tables in LINQ lambda

take look at this sample code from my project

public static IList<Letter> GetDepartmentLettersLinq(int departmentId)
{
    IEnumerable<Letter> allDepartmentLetters =
        from allLetter in LetterService.GetAllLetters()
        join allUser in UserService.GetAllUsers() on allLetter.EmployeeID equals allUser.ID into usersGroup
        from user in usersGroup.DefaultIfEmpty()// here is the tricky part
        join allDepartment in DepartmentService.GetAllDepartments() on user.DepartmentID equals allDepartment.ID
        where allDepartment.ID == departmentId
        select allLetter;

    return allDepartmentLetters.ToArray();
}

in this code I joined 3 tables and I spited join condition from where clause

note: the Services classes are just warped(encapsulate) the database operations

SQL Query to fetch data from the last 30 days?

Pay attention to one aspect when doing "purchase_date>(sysdate-30)": "sysdate" is the current date, hour, minute and second. So "sysdate-30" is not exactly "30 days ago", but "30 days ago at this exact hour".

If your purchase dates have 00.00.00 in hours, minutes, seconds, better doing:

where trunc(purchase_date)>trunc(sysdate-30)

(this doesn't take hours, minutes and seconds into account).

Use of contains in Java ArrayList<String>

You are right. ArrayList.contains() tests equals(), not object identity:

returns true if and only if this list contains at least one element e such that (o==null ? e==null : o.equals(e))

If you got a NullPointerException, verify that you initialized your list, either in a constructor or the declaration. For example:

private List<String> rssFeedURLs = new ArrayList<String>();

How to determine whether a substring is in a different string

People mentioned string.find(), string.index(), and string.indexOf() in the comments, and I summarize them here (according to the Python Documentation):

First of all there is not a string.indexOf() method. The link posted by Deviljho shows this is a JavaScript function.

Second the string.find() and string.index() actually return the index of a substring. The only difference is how they handle the substring not found situation: string.find() returns -1 while string.index() raises an ValueError.

check if "it's a number" function in Oracle

You can use this example

SELECT NVL((SELECT 1 FROM  DUAL WHERE   REGEXP_LIKE (:VALOR,'^[[:digit:]]+$')),0) FROM DUAL;

Use cell's color as condition in if statement (function)

You cannot use VBA (Interior.ColorIndex) in a formula which is why you receive the error.

It is not possible to do this without VBA.

Function YellowIt(rng As Range) As Boolean
    If rng.Interior.ColorIndex = 6 Then
        YellowIt = True
    Else
        YellowIt = False
    End If
End Function

However, I do not recommend this: it is not how user-defined VBA functions (UDFs) are intended to be used. They should reflect the behaviour of Excel functions, which cannot read the colour-formatting of a cell. (This function may not work in a future version of Excel.)

It is far better that you base a formula on the original condition (decision) that makes the cell yellow in the first place. Or, alternatively, run a Sub procedure to fill in the True or False values (although, of course, these values will no longer be linked to the original cell's formatting).

Repeating a function every few seconds

Use a timer. There are 3 basic kinds, each suited for different purposes.

Use only in a Windows Form application. This timer is processed as part of the message loop, so the the timer can be frozen under high load.

When you need synchronicity, use this one. This means that the tick event will be run on the thread that started the timer, allowing you to perform GUI operations without much hassle.

This is the most high-powered timer, which fires ticks on a background thread. This lets you perform operations in the background without freezing the GUI or the main thread.

For most cases, I recommend System.Timers.Timer.

add an element to int [] array in java

This works for me:

int[] list = new int[maximum];
for (int i = 0; i < maximum; i++{
    list[i] = put_input_here;
}

This way, it's simple, yet efficient.

xcode-select active developer directory error

There are only two steps required, and the full XCode.app is not required at all:

sudo rm -rf /Library/Developer/CommandLineTools
xcode-select --install

At this point the "Installing Softwre" dialog pops up:

enter image description here

That's it!

How to set app icon for Electron / Atom Shell App

win = new BrowserWindow({width: 1000, height: 1000,icon: __dirname + '/logo.png'}); //*.png or *.ico will also work 

in my case it worked !

Put a Delay in Javascript

This thread has a good discussion and a useful solution:

function pause( iMilliseconds )
{
    var sDialogScript = 'window.setTimeout( function () { window.close(); }, ' + iMilliseconds + ');';
    window.showModalDialog('javascript:document.writeln ("<script>' + sDialogScript + '<' + '/script>")');
}

Unfortunately it appears that this doesn't work in some versions of IE, but the thread has many other worthy proposals if that proves to be a problem for you.

Firebase FCM notifications click_action payload

I'm looking this Firebase is , development from google cloud messaging push notification fundamental so we can use the gcm tutorial,function and implementation in firebase , i using funtion of gcm push notification function to solve this click_action problem i use gcm function **

'notificationclick'

** try this save url click_action in variable url this is in server-worker.js

var url =  "";

messaging.setBackgroundMessageHandler(function(payload) {

  console.log('[firebase-messaging-sw.js] Received background message ', payload);
  // Customize notification here
  url = payload.data.click_action;

  const notificationTitle = payload.data.title;
  const notificationOptions = {
    body: payload.data.body , 
    icon: 'firebase-logo.png'
  };

  return self.registration.showNotification(notificationTitle,
      notificationOptions);

});


   //i got this in google cloud messaging push notification


self.addEventListener('notificationclick', function (event) {
  event.notification.close();

  var clickResponsePromise = Promise.resolve();
    clickResponsePromise = clients.openWindow(url);

  event.waitUntil(Promise.all([clickResponsePromise, self.analytics.trackEvent('notification-click')]));
});

Best way to check if column returns a null value (from database to .net application)

Just check for

if(table.rows[0][0] == null)
{
     //Whatever I want to do
}

or you could

if(t.Rows[0].IsNull(0))
{
     //Whatever I want to do
}

inserting characters at the start and end of a string

Strings are immutable so you can't insert characters into an existing string. You have to create a new string. You can use string concatenation to do what you want:

yourstring = "L" + yourstring + "LL"

Note that you can also create a string with n Ls by using multiplication:

m = 1
n = 2
yourstring = ("L" * m) + yourstring + ("L" * n)

Make code in LaTeX look *nice*

The listings package is quite nice and very flexible (e.g. different sizes for comments and code).

How to get the index of an element in an IEnumerable?

Stumbled across this today in a search for answers and I thought I'd add my version to the list (No pun intended). It utlises the null conditional operator of c#6.0

IEnumerable<Item> collection = GetTheCollection();

var index = collection
.Select((item,idx) => new { Item = item, Index = idx })
//or .FirstOrDefault(_ =>  _.Item.Prop == something)
.FirstOrDefault(_ => _.Item == itemToFind)?.Index ?? -1;

I've done some 'racing of the old horses' (testing) and for large collections (~100,000), worst case scenario that item you want is at the end, this is 2x faster than doing ToList().FindIndex(). If the Item you want is in the middle its ~4x faster.

For smaller collections (~10,000) it seems to be only marginally faster

Heres how I tested it https://gist.github.com/insulind/16310945247fcf13ba186a45734f254e

Using HTML and Local Images Within UIWebView

Use this:

[webView loadHTMLString:htmlString baseURL:[[NSBundle mainBundle] bundleURL]];

What is the default username and password in Tomcat?

In Tomcat 7, under TOMCAT_HOME/conf/tomcat_users.xml, see the <user /> tag to see password.

Example:

  <role rolename="tomcat"/>
  <role rolename="role1"/>
  <user username="tomcat" password="tomcat" roles="tomcat"/>
  <user username="both" password="tomcat" roles="tomcat,role1"/>
  <user username="role1" password="tomcat" roles="role1"/>

Using C# to read/write Excel files (.xls/.xlsx)

If you want easy to use libraries, you can use the NUGET packages:

  • ExcelDataReader - to read Excel files (most file formats)
  • SwiftExcel - to write Excel files (.xlsx)

Note these are 3rd-Party packages - you can use them for basic functionality for free, but if you want more features there might be a "pro" version.

They are using a two-dimensional object array (i.e. object[][] cells) to read / write data.

Javascript receipt printing using POS Printer

Maybe you could have a look at this if your printer is an epson. There is a javascript driver

http://spsrprofessionals.com/ClientSite/readers/ePOS-Print_SDK_141020E/JavaScript/ePOS-Print_SDK_JS_en_revB.pdf

EDIT:

Previous link seems to be broken

All details about how to use epos of epson are on epson website:

https://reference.epson-biz.com/modules/ref_epos_device_js_en/index.php?content_id=139

How to output something in PowerShell

You simply cannot get PowerShell to ommit those pesky newlines. There is no script or cmdlet that does this.

Of course Write-Host is absolute nonsense because you can't redirect/pipe from it! You simply have to write your own:

using System;

namespace WriteToStdout
{
    class Program
    {
        static void Main(string[] args)
        {
            if (args != null)
            {
                Console.Write(string.Join(" ", args));
            }
        }
    }
}

E.g.

PS C:\> writetostdout finally I can write to stdout like echo -n
finally I can write to stdout like echo -nPS C:\>

Console app arguments, how arguments are passed to Main method

The Main method is the Entry point of your application. If you checkout via ildasm then

.method private hidebysig static void  Main(string[] args) cil managed
{
  .entrypoint

This is what helps in calling the method

The arguments are passed as say C:\AppName arg1 arg2 arg3

Spark read file from S3 using sc.textFile ("s3n://...)

You can add the --packages parameter with the appropriate jar: to your submission:

bin/spark-submit --packages com.amazonaws:aws-java-sdk-pom:1.10.34,org.apache.hadoop:hadoop-aws:2.6.0 code.py

Using LINQ to find item in a List but get "Value cannot be null. Parameter name: source"

This exception could point to the LINQ parameter that is named source:

 System.Linq.Enumerable.Select[TSource,TResult](IEnumerable`1 source, Func`2 selector)

As the source parameter in your LINQ query (var nCounts = from sale in sal) is 'sal', I suppose the list named 'sal' might be null.

Effectively use async/await with ASP.NET Web API

I am not very sure whether it will make any difference in performance of my API.

Bear in mind that the primary benefit of asynchronous code on the server side is scalability. It won't magically make your requests run faster. I cover several "should I use async" considerations in my article on async ASP.NET.

I think your use case (calling other APIs) is well-suited for asynchronous code, just bear in mind that "asynchronous" does not mean "faster". The best approach is to first make your UI responsive and asynchronous; this will make your app feel faster even if it's slightly slower.

As far as the code goes, this is not asynchronous:

public Task<BackOfficeResponse<List<Country>>> ReturnAllCountries()
{
  var response = _service.Process<List<Country>>(BackOfficeEndpoint.CountryEndpoint, "returnCountries");
  return Task.FromResult(response);
}

You'd need a truly asynchronous implementation to get the scalability benefits of async:

public async Task<BackOfficeResponse<List<Country>>> ReturnAllCountriesAsync()
{
  return await _service.ProcessAsync<List<Country>>(BackOfficeEndpoint.CountryEndpoint, "returnCountries");
}

Or (if your logic in this method really is just a pass-through):

public Task<BackOfficeResponse<List<Country>>> ReturnAllCountriesAsync()
{
  return _service.ProcessAsync<List<Country>>(BackOfficeEndpoint.CountryEndpoint, "returnCountries");
}

Note that it's easier to work from the "inside out" rather than the "outside in" like this. In other words, don't start with an asynchronous controller action and then force downstream methods to be asynchronous. Instead, identify the naturally asynchronous operations (calling external APIs, database queries, etc), and make those asynchronous at the lowest level first (Service.ProcessAsync). Then let the async trickle up, making your controller actions asynchronous as the last step.

And under no circumstances should you use Task.Run in this scenario.

Div 100% height works on Firefox but not in IE

I'm not sure what problem you are solving, but when I have two side by side containers that need to be the same height, I run a little javascript on page load that finds the maximum height of the two and explicitly sets the other to the same height. It seems to me that height: 100% might just mean "make it the size needed to fully contain the content" when what you really want is "make both the size of the largest content."

Note: you'll need to resize them again if anything happens on the page to change their height -- like a validation summary being made visible or a collapsible menu opening.

Replace specific characters within strings

Regular expressions are your friends:

R> ## also adds missing ')' and sets column name
R> group<-data.frame(group=c("12357e", "12575e", "197e18", "e18947"))  )
R> group
   group
1 12357e
2 12575e
3 197e18
4 e18947

Now use gsub() with the simplest possible replacement pattern: empty string:

R> group$groupNoE <- gsub("e", "", group$group)
R> group
   group groupNoE
1 12357e    12357
2 12575e    12575
3 197e18    19718
4 e18947    18947
R> 

How can I find the first and last date in a month using PHP?

This will give you the last day of the month:

function lastday($month = '', $year = '') {
   if (empty($month)) {
      $month = date('m');
   }
   if (empty($year)) {
      $year = date('Y');
   }
   $result = strtotime("{$year}-{$month}-01");
   $result = strtotime('-1 second', strtotime('+1 month', $result));
   return date('Y-m-d', $result);
}

And the first Day:

function firstDay($month = '', $year = '')
{
    if (empty($month)) {
      $month = date('m');
   }
   if (empty($year)) {
      $year = date('Y');
   }
   $result = strtotime("{$year}-{$month}-01");
   return date('Y-m-d', $result);
} 

how to convert current date to YYYY-MM-DD format with angular 2

Solution in ES6/TypeScript:

let d = new Date;
console.log(d, [`${d.getFullYear()}`, `0${d.getMonth()}`.substr(-2), `0${d.getDate()}`.substr(-2)].join("-"));

pip install access denied on Windows

Try to give permission to full control the python folder.

Find the python root directory-->right button click-->properties-->security-->edit-->give users Full Control-->yes and wait the process finished.

It works for me.

Batch file to perform start, run, %TEMP% and delete all

@echo off    
del /s /f /q %windir%\temp\*.*    
rd /s /q %windir%\temp    
md %windir%\temp    
del /s /f /q %windir%\Prefetch\*.*    
rd /s /q %windir%\Prefetch    
md %windir%\Prefetch    
del /s /f /q %windir%\system32\dllcache\*.*    
rd /s /q %windir%\system32\dllcache    
md %windir%\system32\dllcache    
del /s /f /q "%SysteDrive%\Temp"\*.*    
rd /s /q "%SysteDrive%\Temp"    
md "%SysteDrive%\Temp"    
del /s /f /q %temp%\*.*    
rd /s /q %temp%    
md %temp%    
del /s /f /q "%USERPROFILE%\Local Settings\History"\*.*    
rd /s /q "%USERPROFILE%\Local Settings\History"    
md "%USERPROFILE%\Local Settings\History"    
del /s /f /q "%USERPROFILE%\Local Settings\Temporary Internet Files"\*.*    
rd /s /q "%USERPROFILE%\Local Settings\Temporary Internet Files"    
md "%USERPROFILE%\Local Settings\Temporary Internet Files"    
del /s /f /q "%USERPROFILE%\Local Settings\Temp"\*.*    
rd /s /q "%USERPROFILE%\Local Settings\Temp"    
md "%USERPROFILE%\Local Settings\Temp"    
del /s /f /q "%USERPROFILE%\Recent"\*.*    
rd /s /q "%USERPROFILE%\Recent"    
md "%USERPROFILE%\Recent"    
del /s /f /q "%USERPROFILE%\Cookies"\*.*    
rd /s /q "%USERPROFILE%\Cookies"    
md "%USERPROFILE%\Cookies"

How to create a property for a List<T>

You could do this but the T generic parameter needs to be declared at the containing class:

public class Foo<T>
{
    public List<T> NewList { get; set; }
}

Is there a float input type in HTML5?

Via: http://blog.isotoma.com/2012/03/html5-input-typenumber-and-decimalsfloats-in-chrome/

But what if you want all the numbers to be valid, integers and decimals alike? In this case, set step to “any”

<input type="number" step="any" />

Works for me in Chrome, not tested in other browsers.

Short rot13 function - Python

The following function rot(s, n) encodes a string s with ROT-n encoding for any integer n, with n defaulting to 13. Both upper- and lowercase letters are supported. Values of n over 26 or negative values are handled appropriately, e.g., shifting by 27 positions is equal to shifting by one position. Decoding is done with invrot(s, n).

import string

def rot(s, n=13):
    '''Encode string s with ROT-n, i.e., by shifting all letters n positions.
    When n is not supplied, ROT-13 encoding is assumed.
    '''
    upper = string.ascii_uppercase
    lower = string.ascii_lowercase
    upper_start = ord(upper[0])
    lower_start = ord(lower[0])
    out = ''
    for letter in s:
        if letter in upper:
            out += chr(upper_start + (ord(letter) - upper_start + n) % 26)
        elif letter in lower:
            out += chr(lower_start + (ord(letter) - lower_start + n) % 26)
        else:
            out += letter
    return(out)

def invrot(s, n=13):
    '''Decode a string s encoded with ROT-n-encoding
    When n is not supplied, ROT-13 is assumed.
    '''
    return(rot(s, -n))

Using BigDecimal to work with currencies

Here are a few hints:

  1. Use BigDecimal for computations if you need the precision that it offers (Money values often need this).
  2. Use the NumberFormat class for display. This class will take care of localization issues for amounts in different currencies. However, it will take in only primitives; therefore, if you can accept the small change in accuracy due to transformation to a double, you could use this class.
  3. When using the NumberFormat class, use the scale() method on the BigDecimal instance to set the precision and the rounding method.

PS: In case you were wondering, BigDecimal is always better than double, when you have to represent money values in Java.

PPS:

Creating BigDecimal instances

This is fairly simple since BigDecimal provides constructors to take in primitive values, and String objects. You could use those, preferably the one taking the String object. For example,

BigDecimal modelVal = new BigDecimal("24.455");
BigDecimal displayVal = modelVal.setScale(2, RoundingMode.HALF_EVEN);

Displaying BigDecimal instances

You could use the setMinimumFractionDigits and setMaximumFractionDigits method calls to restrict the amount of data being displayed.

NumberFormat usdCostFormat = NumberFormat.getCurrencyInstance(Locale.US);
usdCostFormat.setMinimumFractionDigits( 1 );
usdCostFormat.setMaximumFractionDigits( 2 );
System.out.println( usdCostFormat.format(displayVal.doubleValue()) );

JAVA_HOME is set to an invalid directory:

You need to set with only C:\Program Files\Java\jdk1.8.0_12.

And check with using new cmd. It will be updated

The simplest way to resize an UIImage?

Here's a modification of the category written by iWasRobbed above. It keeps the aspect ratio of the original image instead of distorting it.

- (UIImage*)scaleToSizeKeepAspect:(CGSize)size {
    UIGraphicsBeginImageContext(size);

    CGFloat ws = size.width/self.size.width;
    CGFloat hs = size.height/self.size.height;

    if (ws > hs) {
        ws = hs/ws;
        hs = 1.0;
    } else {
        hs = ws/hs;
        ws = 1.0;
    }

    CGContextRef context = UIGraphicsGetCurrentContext();
    CGContextTranslateCTM(context, 0.0, size.height);
    CGContextScaleCTM(context, 1.0, -1.0);

    CGContextDrawImage(context, CGRectMake(size.width/2-(size.width*ws)/2,
        size.height/2-(size.height*hs)/2, size.width*ws,
        size.height*hs), self.CGImage);

    UIImage* scaledImage = UIGraphicsGetImageFromCurrentImageContext();

    UIGraphicsEndImageContext();

    return scaledImage;
}

Inputting a default image in case the src attribute of an html <img> is not valid?

angular2:

<img src="{{foo.url}}" onerror="this.src='path/to/altimg.png'">

How to output to the console and file?

I came up with this [untested]

import sys

class Tee(object):
    def __init__(self, *files):
        self.files = files
    def write(self, obj):
        for f in self.files:
            f.write(obj)
            f.flush() # If you want the output to be visible immediately
    def flush(self) :
        for f in self.files:
            f.flush()

f = open('out.txt', 'w')
original = sys.stdout
sys.stdout = Tee(sys.stdout, f)
print "test"  # This will go to stdout and the file out.txt

#use the original
sys.stdout = original
print "This won't appear on file"  # Only on stdout
f.close()

print>>xyz in python will expect a write() function in xyz. You could use your own custom object which has this. Or else, you could also have sys.stdout refer to your object, in which case it will be tee-ed even without >>xyz.

MySQL delete multiple rows in one query conditions unique to each row

You were very close, you can use this:

DELETE FROM table WHERE (col1,col2) IN ((1,2),(3,4),(5,6))

Please see this fiddle.

How to tell Maven to disregard SSL errors (and trusting all certs)?

Create a folder ${USER_HOME}/.mvn and put a file called maven.config in it.

The content should be:

-Dmaven.wagon.http.ssl.insecure=true
-Dmaven.wagon.http.ssl.allowall=true
-Dmaven.wagon.http.ssl.ignore.validity.dates=true

Hope this helps.

pythonw.exe or python.exe?

If you're going to call a python script from some other process (say, from the command line), use pythonw.exe. Otherwise, your user will continuously see a cmd window launching the python process. It'll still run your script just the same, but it won't intrude on the user experience.

An example might be sending an email; python.exe will pop up a CLI window, send the email, then close the window. It'll appear as a quick flash, and can be considered somewhat annoying. pythonw.exe avoids this, but still sends the email.

Configuring IntelliJ IDEA for unit testing with JUnit

One way of doing this is to do add junit.jar to your $CLASSPATH as an external dependency.

adding junit intellij

So to do that, go to project structure, and then add JUnit as one of the libraries as shown in the gif.

In the 'Choose Modules' prompt choose only the modules that you'd need JUnit for.

Which is the fastest algorithm to find prime numbers?

Rabin-Miller is a standard probabilistic primality test. (you run it K times and the input number is either definitely composite, or it is probably prime with probability of error 4-K. (a few hundred iterations and it's almost certainly telling you the truth)

There is a non-probabilistic (deterministic) variant of Rabin Miller.

The Great Internet Mersenne Prime Search (GIMPS) which has found the world's record for largest proven prime (274,207,281 - 1 as of June 2017), uses several algorithms, but these are primes in special forms. However the GIMPS page above does include some general deterministic primality tests. They appear to indicate that which algorithm is "fastest" depends upon the size of the number to be tested. If your number fits in 64 bits then you probably shouldn't use a method intended to work on primes of several million digits.

Eclipse EGit Checkout conflict with files: - EGit doesn't want to continue

This is the way I solved my problem:

  1. Right click the folder that has uncommitted changes on your local
  2. Click Team > Advanced > Assume Unchanged
  3. Pull from master.

UPDATE:

As Hugo Zuleta rightly pointed out, you should be careful while applying this. He says that it might end up saying the branch is up to date, but the changes aren't shown, resulting in desync from the branch.

How to undo 'git reset'?

Old question, and the posted answers work great. I'll chime in with another option though.

git reset ORIG_HEAD

ORIG_HEAD references the commit that HEAD previously referenced.

Identifying and removing null characters in UNIX

A large number of unwanted NUL characters, say one every other byte, indicates that the file is encoded in UTF-16 and that you should use iconv to convert it to UTF-8.

Grant Select on a view not base table when base table is in a different database

Create view Schema1.viewName1 as (select * from plaplapla)

Schema1 has all the tables

Create view Schema2.viewName2 as (select * from schema1.viewName1)

schema2 has no tables(only views schema)

In this case you can execute (select * from viewName2) in schema2 , BUT .. If you deleted viewNmae1 from Schema1 , Then ViewName2 will not work..

Amani El Gamal [email protected]

jQuery preventDefault() not triggered

i just had the same problems - have been testing a lot of different stuff. but it just wouldn't work. then i checked the tutorial examples on jQuery.com again and found out:

your jQuery script needs to be after the elements you are referring to !

so your script needs to be after the html-code you want to access!

seems like jQuery can't access it otherwise.

How to get name of the computer in VBA?

Looks like I'm late to the game, but this is a common question...

This is probably the code you want.

Please note that this code is in the public domain, from Usenet, MSDN, and the Excellerando blog.

Public Function ComputerName() As String
'' Returns the host name

'' Uses late-binding: bad for performance and stability, useful for 
'' code portability. The correct declaration is:

'   Dim objNetwork  As IWshRuntimeLibrary.WshNetwork
'   Set objNetwork = New IWshRuntimeLibrary.WshNetwork

    Dim objNetwork As Object
    Set objNetwork = CreateObject("WScript.Network")

    ComputerName = objNetwork.ComputerName
    
    Set objNetwork = Nothing

End Function

You'll probably need this, too:

Public Function UserName(Optional WithDomain As Boolean = False) As String
'' Returns the user's network name

'' Uses late-binding: bad for performance and stability, useful for
'' code portability. The correct declaration is:

'   Dim objNetwork  As IWshRuntimeLibrary.WshNetwork
'   Set objNetwork = New IWshRuntimeLibrary.WshNetwork


    Dim objNetwork As Object
    Set objNetwork = CreateObject("WScript.Network")

    If WithDomain Then
        UserName = objNetwork.UserDomain & "\" & objNetwork.UserName
    Else
        UserName = objNetwork.UserName
    End If
    
    Set objNetwork = Nothing

End Function

Log exception with traceback

Uncaught exception messages go to STDERR, so instead of implementing your logging in Python itself you could send STDERR to a file using whatever shell you're using to run your Python script. In a Bash script, you can do this with output redirection, as described in the BASH guide.

Examples

Append errors to file, other output to the terminal:

./test.py 2>> mylog.log

Overwrite file with interleaved STDOUT and STDERR output:

./test.py &> mylog.log

CSS 100% height with padding/margin

According the w3c spec height refers to the height of the viewable area e.g. on a 1280x1024 pixel resolution monitor 100% height = 1024 pixels.

min-height refers to the total height of the page including content so on a page where the content is bigger than 1024px min-height:100% will stretch to include all of the content.

The other problem then is that padding and border are added to the height and width in most modern browsers except ie6(ie6 is actually quite logical but does not conform to the spec). This is called the box model. So if you specify

min-height: 100%;
padding: 5px; 

It will actually give you 100% + 5px + 5px for the height. To get around this you need a wrapper container.

<style>
    .FullHeight { 
       height: auto !important; /* ie 6 will ignore this */
       height: 100%;            /* ie 6 will use this instead of min-height */
       min-height: 100%;        /* ie 6 will ignore this */
    }

    .Padded {
       padding: 5px;
    }
</style>

<div class="FullHeight">
   <div class="Padded">
      Hello i am padded.
   </div
</div>

How to initialize a variable of date type in java?

java.util.Date constructor with parameters like new Date(int year, int month, int date, int hrs, int min). is deprecated and preferably do not use it any more. Oracle docs prefers the way over java.util.Calendar. So you can set any date and instantiate Date object through the getTime() method.

Calendar calendar = Calendar.getInstance();
calendar.set(2018, 11, 31, 59, 59, 59);
Date happyNewYearDate = calendar.getTime();

Notice that month number starts from 0

Downloading folders from aws s3, cp or sync?

In the case you want to download a single file, you can try the following command:

aws s3 cp s3://bucket/filename /path/to/dest/folder

Exercises to improve my Java programming skills

Once you are quite good in Java SE (lets say you are able to pass SCJP), I'd suggest you get junior Java programmer job and improve yourself on real world problems

100% height minus header?

For "100% of the browser window", if you mean this literally, you should use fixed positioning. The top, bottom, right, and left properties are then used to offset the divs edges from the respective edges of the viewport:

#nav, #content{position:fixed;top:0px;bottom:0px;}
#nav{left:0px;right:235px;}
#content{left:235px;right:0px}

This will set up a screen with the left 235 pixels devoted to the nav, and the right rest of the screen to content.

Note, however, you won't be able to scroll the whole screen at once. Though you can set it to scroll either pane individually, by applying overflow:auto to either div.

Note also: fixed positioning is not supported in IE6 or earlier.

How to execute Ant build in command line

is it still actual?

As I can see you wrote <target depends="build-subprojects,build-project" name="build"/>, then you wrote <target name="build-subprojects"/> (it does nothing). Could it be a reason? Does this <echo message="${ant.project.name}: ${ant.file}"/> print appropriate message? If no then target is not running. Take a look at the next link http://www.sqaforums.com/showflat.php?Number=623277

How can I check if an argument is defined when starting/calling a batch file?

Get rid of the parentheses.

Sample batch file:

echo "%1"

if ("%1"=="") echo match1

if "%1"=="" echo match2

Output from running above script:

C:\>echo "" 
""

C:\>if ("" == "") echo match1 

C:\>if "" == "" echo match2 
match2

I think it is actually taking the parentheses to be part of the strings and they are being compared.

Webdriver Screenshot

driver.save_screenshot("path to save \\screen.jpeg")

Where could I buy a valid SSL certificate?

Let's Encrypt is a free, automated, and open certificate authority made by the Internet Security Research Group (ISRG). It is sponsored by well-known organisations such as Mozilla, Cisco or Google Chrome. All modern browsers are compatible and trust Let's Encrypt.

All certificates are free (even wildcard certificates)! For security reasons, the certificates expire pretty fast (after 90 days). For this reason, it is recommended to install an ACME client, which will handle automatic certificate renewal.

There are many clients you can use to install a Let's Encrypt certificate:

Let’s Encrypt uses the ACME protocol to verify that you control a given domain name and to issue you a certificate. To get a Let’s Encrypt certificate, you’ll need to choose a piece of ACME client software to use. - https://letsencrypt.org/docs/client-options/

Automatic vertical scroll bar in WPF TextBlock?

Dont know if someone else has this problem but wrapping my TextBlock into a ScrollViewer somewhow messed up my UI - as a simple workaround I figured out that replacing the TextBlock by a TextBox like this one

<TextBox  Name="textBlock" SelectionBrush="Transparent" Cursor="Arrow" IsReadOnly="True" Text="My Text" VerticalScrollBarVisibility="Auto">

creates a TextBox that looks and behaves like a TextBlock with a scrollbar (and you can do it all in the designer).

How To Make Circle Custom Progress Bar in Android

I've encountered same problem and not found any appropriate solution for my case, so I decided to go another way. I've created custom drawable class. Within this class I've created 2 Paints for progress line and background line (with some bigger stroke). First of all set startAngle and sweepAngle in constructor:

    mSweepAngle = 0;
    mStartAngle = 270;

Here is onDraw method of this class:

@Override
public void draw(Canvas canvas) {
    // draw background line
    canvas.drawArc(mRectF, 0, 360, false, mPaintBackground);
    // draw progress line
    canvas.drawArc(mRectF, mStartAngle, mSweepAngle, false, mPaintProgress);
}

So now all you need to do is set this drawable as a backgorund of the view, in background thread change sweepAngle:

mSweepAngle += 360 / totalTimerTime // this is mStep

and directly call InvalidateSelf() with some interval (e.g every 1 second or more often if you want smooth progress changes) on the view that have this drawable as a background. Thats it!

P.S. I know, I know...of course you want some more code. So here it is all flow:

  1. Create XML view :

     <View
     android:id="@+id/timer"
     android:layout_width="match_parent"
     android:layout_height="match_parent"/>
    
  2. Create and configure Custom Drawable class (as I described above). Don't forget to setup Paints for lines. Here paint for progress line:

    mPaintProgress = new Paint();
    mPaintProgress.setAntiAlias(true);
    mPaintProgress.setStyle(Paint.Style.STROKE);
    mPaintProgress.setStrokeWidth(widthProgress);
    mPaintProgress.setStrokeCap(Paint.Cap.ROUND);
    mPaintProgress.setColor(colorThatYouWant);
    

Same for backgroung paint (set width little more if you want)

  1. In drawable class create method for updating (Step calculation described above)

    public void update() {
        mSweepAngle += mStep;
        invalidateSelf();
    }
    
  2. Set this drawable class to YourTimerView (I did it in runtime) - view with @+id/timer from xml above:

    OurSuperDrawableClass superDrawable = new OurSuperDrawableClass(); YourTimerView.setBackgroundDrawable(superDrawable);

  3. Create background thread with runnable and update view:

    YourTimerView.post(new Runnable() {
        @Override
        public void run() {
            // update progress view
            superDrawable.update();
        }
    });
    

Thats it ! Enjoy your cool progress bar. Here screenshot of result if you're too bored of this amount of text.enter image description here

How to display image from database using php

$sqlimage  = "SELECT image FROM userdetail where `id` = $id1";
    $imageresult1 = mysqli_query($link, $sqlimage);

    while($rows=mysqli_fetch_assoc($imageresult1))
{

    echo "<img src = 'Image/".$row['image'].'" />';


} 

An efficient compression algorithm for short text strings

Check out Smaz:

Smaz is a simple compression library suitable for compressing very short strings.

Pick images of root folder from sub-folder

when you upload your files to the server be careful ,some tomes your images will not appear on the web page and a crashed icon will appear that means your file path is not properly arranged or coded when you have the the following file structure the code should be like this File structure: ->web(main folder) ->images(subfolder)->logo.png(image in the sub folder)the code for the above is below follow this standard

<img src="../images/logo.jpg" alt="image1" width="50px" height="50px">

if you uploaded your files to the web server by neglecting the file structure with out creating the folder web if you directly upload the files then your images will be broken you can't see images,then change the code as following

<img src="images/logo.jpg" alt="image1" width="50px" height="50px">

thank you->vamshi krishnan

Assigning the return value of new by reference is deprecated

C:\wamp\www\..\libraries\pattemplate

1.ini_set('display_errors', 0);

$this->_modules[$moduleType][$sig]  =&new $moduleClass;   wrong

$this->_modules[$moduleType][$sig]  =new $moduleClass;   Right

Java : Comparable vs Comparator

Comparator provides a way for you to provide custom comparison logic for types that you have no control over.

Comparable allows you to specify how objects that you are implementing get compared.

Obviously, if you don't have control over a class (or you want to provide multiple ways to compare objects that you do have control over) then use Comparator.

Otherwise you can use Comparable.

Android fastboot waiting for devices

To use the fastboot command you first need to put your device in fastboot mode:

$ adb reboot bootloader

Once the device is in fastboot mode, you can boot it with your own kernel, for example:

$ fastboot boot myboot.img

The above will only boot your kernel once and the old kernel will be used again when you reboot the device. To replace the kernel on the device, you will need to flash it to the device:

$ fastboot flash boot myboot.img

Hope that helps.

Cannot get OpenCV to compile because of undefined references?

This is a linker issue. Try:

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

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

sudo ldconfig

How do I avoid the specification of the username and password at every git push?

You have to setup a SSH private key, you can review this page, how to do the setup on Mac, if you are on linux the guide should be almost the same, on Windows you would need tool like MSYS.

CSS3 Transparency + Gradient

This is some really cool stuff! I needed pretty much the same, but with horizontal gradient from white to transparent. And it is working just fine! Here ist my code:

.gradient{
        /* webkit example */
        background-image: -webkit-gradient(
          linear, right top, left top, from(rgba(255, 255, 255, 1.0)),
          to(rgba(255, 255, 255, 0))
        );

        /* mozilla example - FF3.6+ */
        background-image: -moz-linear-gradient(
          right center,
          rgba(255, 255, 255, 1.0) 20%, rgba(255, 255, 255, 0) 95%
        );

        /* IE 5.5 - 7 */
        filter: progid:DXImageTransform.Microsoft.gradient(
          gradientType=1, startColor=0, endColorStr=#FFFFFF
        );

        /* IE8 uses -ms-filter for whatever reason... */
        -ms-filter: progid:DXImageTransform.Microsoft.gradient(
          gradientType=1, startColor=0, endColoStr=#FFFFFF
        );
    }

How do I get the color from a hexadecimal color code using .NET?

in asp.net:

color_black = (Color)new ColorConverter().ConvertFromString("#FF76B3");

Simulate CREATE DATABASE IF NOT EXISTS for PostgreSQL?

I had to use a slightly extended version @Erwin Brandstetter used:

DO
$do$
DECLARE
  _db TEXT := 'some_db';
  _user TEXT := 'postgres_user';
  _password TEXT := 'password';
BEGIN
  CREATE EXTENSION IF NOT EXISTS dblink; -- enable extension 
  IF EXISTS (SELECT 1 FROM pg_database WHERE datname = _db) THEN
    RAISE NOTICE 'Database already exists';
  ELSE
    PERFORM dblink_connect('host=localhost user=' || _user || ' password=' || _password || ' dbname=' || current_database());
    PERFORM dblink_exec('CREATE DATABASE ' || _db);
  END IF;
END
$do$

I had to enable the dblink extension, plus i had to provide the credentials for dblink. Works with Postgres 9.4.

Create XML file using java

You can use a DOM XML parser to create an XML file using Java. A good example can be found on this site:

try {
    DocumentBuilderFactory docFactory = DocumentBuilderFactory.newInstance();
    DocumentBuilder docBuilder = docFactory.newDocumentBuilder();

    //root elements
    Document doc = docBuilder.newDocument();

    Element rootElement = doc.createElement("company");
    doc.appendChild(rootElement);

    //staff elements
    Element staff = doc.createElement("Staff");
    rootElement.appendChild(staff);

    //set attribute to staff element
    Attr attr = doc.createAttribute("id");
    attr.setValue("1");
    staff.setAttributeNode(attr);

    //shorten way
    //staff.setAttribute("id", "1");

    //firstname elements
    Element firstname = doc.createElement("firstname");
    firstname.appendChild(doc.createTextNode("yong"));
    staff.appendChild(firstname);

    //lastname elements
    Element lastname = doc.createElement("lastname");
    lastname.appendChild(doc.createTextNode("mook kim"));
    staff.appendChild(lastname);

    //nickname elements
    Element nickname = doc.createElement("nickname");
    nickname.appendChild(doc.createTextNode("mkyong"));
    staff.appendChild(nickname);

    //salary elements
    Element salary = doc.createElement("salary");
    salary.appendChild(doc.createTextNode("100000"));
    staff.appendChild(salary);

    //write the content into xml file
    TransformerFactory transformerFactory =  TransformerFactory.newInstance();
    Transformer transformer = transformerFactory.newTransformer();
    DOMSource source = new DOMSource(doc);

    StreamResult result =  new StreamResult(new File("C:\\testing.xml"));
    transformer.transform(source, result);

    System.out.println("Done");

}catch(ParserConfigurationException pce){
    pce.printStackTrace();
}catch(TransformerException tfe){
    tfe.printStackTrace();
}

Check if value exists in Postgres array

but if you have other ways to do it please share.

You can compare two arrays. If any of the values in the left array overlap the values in the right array, then it returns true. It's kind of hackish, but it works.

SELECT '{1}'   && '{1,2,3}'::int[];  -- true
SELECT '{1,4}' && '{1,2,3}'::int[];  -- true
SELECT '{4}'   && '{1,2,3}'::int[];  -- false
  • In the first and second query, value 1 is in the right array
  • Notice that the second query is true, even though the value 4 is not contained in the right array
  • For the third query, no values in the left array (i.e., 4) are in the right array, so it returns false

How to disable SSL certificate checking with Spring RestTemplate?

For the sake of other developers who finds this question and need another solution that fits not only for unit-tests:

I've found this on a blog (not my solution! Credit to the blog's owner).

TrustStrategy acceptingTrustStrategy = (X509Certificate[] chain, String authType) -> true;

SSLContext sslContext = org.apache.http.ssl.SSLContexts.custom()
        .loadTrustMaterial(null, acceptingTrustStrategy)
        .build();

SSLConnectionSocketFactory csf = new SSLConnectionSocketFactory(sslContext);

CloseableHttpClient httpClient = HttpClients.custom()
        .setSSLSocketFactory(csf)
        .build();

HttpComponentsClientHttpRequestFactory requestFactory =
        new HttpComponentsClientHttpRequestFactory();

requestFactory.setHttpClient(httpClient);

RestTemplate restTemplate = new RestTemplate(requestFactory);

Extract file name from path, no matter what the os/path format

fname = str("C:\Windows\paint.exe").split('\\')[-1:][0]

this will return : paint.exe

change the sep value of the split function regarding your path or OS.

Add a default value to a column through a migration

Execute:

rails generate migration add_column_to_table column:boolean

It will generate this migration:

class AddColumnToTable < ActiveRecord::Migration
  def change
    add_column :table, :column, :boolean
  end
end

Set the default value adding :default => 1

add_column :table, :column, :boolean, :default => 1

Run:

rake db:migrate

How to display Toast in Android?

Show Toast from Service

public class ServiceA extends Service {
    //....
    public void showToast(final String message) {
        Handler handler = new Handler(Looper.getMainLooper());
        handler.post(new Runnable() {

            @Override
            public void run() {
                Toast.makeText(getContext(), message, Toast.LENGTH_LONG).show();
            }
        });
    }
    //....
}

You can also put showToast method in your Application class, and show toast from anywhere.

GIT commit as different user without email / or only email

The specific format is:

git commit --author="John Doe <[email protected]>" -m "Impersonation is evil." 

How should I read a file line-by-line in Python?

if you're turned off by the extra line, you can use a wrapper function like so:

def with_iter(iterable):
    with iterable as iter:
        for item in iter:
            yield item

for line in with_iter(open('...')):
    ...

in Python 3.3, the yield from statement would make this even shorter:

def with_iter(iterable):
    with iterable as iter:
        yield from iter

What is a good regular expression to match a URL?

Another possible solution, above solution failed for me in parsing query string params.

var regex = new RegExp("^(http[s]?:\\/\\/(www\\.)?|ftp:\\/\\/(www\\.)?|www\\.){1}([0-9A-Za-z-\\.@:%_\+~#=]+)+((\\.[a-zA-Z]{2,3})+)(/(.)*)?(\\?(.)*)?");

if(regex.test("http://google.com")){
  alert("Successful match");
}else{
  alert("No match");
}

In this solution please feel free to modify [-0-9A-Za-z\.@:%_\+~#=, to match the domain/sub domain name. In this solution query string parameters are also taken care.

If you are not using RegEx, then from the expression replace \\ by \.

Hope this helps.

How to beautifully update a JPA entity in Spring Data?

In Spring Data you simply define an update query if you have the ID

  @Repository
  public interface CustomerRepository extends JpaRepository<Customer , Long> {

     @Query("update Customer c set c.name = :name WHERE c.id = :customerId")
     void setCustomerName(@Param("customerId") Long id, @Param("name") String name);

  }

Some solutions claim to use Spring data and do JPA oldschool (even in a manner with lost updates) instead.

macro - open all files in a folder

You can use Len(StrFile) > 0 in loop check statement !

Sub openMyfile()

    Dim Source As String
    Dim StrFile As String

    'do not forget last backslash in source directory.
    Source = "E:\Planning\03\"
    StrFile = Dir(Source)

    Do While Len(StrFile) > 0                        
        Workbooks.Open Filename:=Source & StrFile
        StrFile = Dir()
    Loop
End Sub

Angles between two n-dimensional vectors in Python

import math

def dotproduct(v1, v2):
  return sum((a*b) for a, b in zip(v1, v2))

def length(v):
  return math.sqrt(dotproduct(v, v))

def angle(v1, v2):
  return math.acos(dotproduct(v1, v2) / (length(v1) * length(v2)))

Note: this will fail when the vectors have either the same or the opposite direction. The correct implementation is here: https://stackoverflow.com/a/13849249/71522

Hive: how to show all partitions of a table?

You can see Hive MetaStore tables,Partitions information in table of "PARTITIONS". You could use "TBLS" join "Partition" to query special table partitions.

Sending HTTP POST Request In Java

Call HttpURLConnection.setRequestMethod("POST") and HttpURLConnection.setDoOutput(true); Actually only the latter is needed as POST then becomes the default method.

How to echo xml file in php

Here's what worked for me:

<pre class="prettyprint linenums">
    <code class="language-xml"><?php echo htmlspecialchars(file_get_contents("example.xml"), ENT_QUOTES); ?></code>
</pre>

Using htmlspecialchars will prevent tags from being displayed as html and won't break anything. Note that I'm using Prettyprint to highlight the code ;)

SQL Row_Number() function in Where Clause

Using CTE (SQL Server 2005+):

WITH employee_rows AS (
  SELECT t.employee_id,
         ROW_NUMBER() OVER ( ORDER BY t.employee_id ) 'rownum'
    FROM V_EMPLOYEE t)
SELECT er.employee_id
  FROM employee_rows er
 WHERE er.rownum > 1

Using Inline view/Non-CTE Equivalent Alternative:

SELECT er.employee_id
  FROM (SELECT t.employee_id,
               ROW_NUMBER() OVER ( ORDER BY t.employee_id ) 'rownum'
          FROM V_EMPLOYEE t) er
 WHERE er.rownum > 1

How to add an onchange event to a select box via javascript?

replace:

transport_select.onChange = function(){toggleSelect(transport_select_id);};

with:

transport_select.onchange = function(){toggleSelect(transport_select_id);};

on'C'hange >> on'c'hange


You can use addEventListener too.

How to get "their" changes in the middle of conflicting Git rebase?

You want to use:

git checkout --ours foo/bar.java
git add foo/bar.java

If you rebase a branch feature_x against main (i.e. running git rebase main while on branch feature_x), during rebasing ours refers to main and theirs to feature_x.

As pointed out in the git-rebase docs:

Note that a rebase merge works by replaying each commit from the working branch on top of the branch. Because of this, when a merge conflict happens, the side reported as ours is the so-far rebased series, starting with <upstream>, and theirs is the working branch. In other words, the sides are swapped.

For further details read this thread.

How to delete session cookie in Postman?

into Chrome, right click -> Inspect Element. Go to the tab active tracking of resources and if you have not already. Now the left hand sidebar thingy down until you see "Cookies", click below your domain name and to remove a cookie just right-click on it and "Delete"

Sending the bearer token with axios

axios by itself comes with two useful "methods" the interceptors that are none but middlewares between the request and the response. so if on each request you want to send the token. Use the interceptor.request.

I made apackage that helps you out:

$ npm i axios-es6-class

Now you can use axios as class

export class UserApi extends Api {
    constructor (config) {
        super(config);

        // this middleware is been called right before the http request is made.
        this.interceptors.request.use(param => {
            return {
                ...param,
                defaults: {
                    headers: {
                        ...param.headers,
                        "Authorization": `Bearer ${this.getToken()}`
                    },
                }
            }
        });

      this.login = this.login.bind(this);
      this.getSome = this.getSome.bind(this);
   }

   login (credentials) {
      return this.post("/end-point", {...credentials})
      .then(response => this.setToken(response.data))
      .catch(this.error);
   }


   getSome () {
      return this.get("/end-point")
      .then(this.success)
      .catch(this.error);
   }
}

I mean the implementation of the middleware depends on you, or if you prefer to create your own axios-es6-class https://medium.com/@enetoOlveda/how-to-use-axios-typescript-like-a-pro-7c882f71e34a it is the medium post where it came from

Is it possible to run an .exe or .bat file on 'onclick' in HTML

It is possible when the page itself is opened via a file:/// path.

<button onclick="window.open('file:///C:/Windows/notepad.exe')">
    Launch notepad
</button>

However, the moment you put it on a webserver (even if you access it via http://localhost/), you will get an error:

Error: Access to 'file:///C:/Windows/notepad.exe' from script denied

ImportError: cannot import name NUMPY_MKL

Reinstall numpy-1.11.0_XXX.whl (for your Python) from www.lfd.uci.edu/~gohlke/pythonlibs. This file has the same name and version if compare with the variant downloaded by me earlier 29.03.2016, but its size and content differ from old variant. After re-installation error disappeared.

Second option - return back to scipy 0.17.0 from 0.17.1

P.S. I use Windows 64-bit version of Python 3.5.1, so can't guarantee that numpy for Python 2.7 is already corrected.

Python nonlocal statement

In short, it lets you assign values to a variable in an outer (but non-global) scope. See PEP 3104 for all the gory details.

Fastest way to flatten / un-flatten nested JSON objects

Here is some code I wrote to flatten an object I was working with. It creates a new class that takes every nested field and brings it into the first layer. You could modify it to unflatten by remembering the original placement of the keys. It also assumes the keys are unique even across nested objects. Hope it helps.

class JSONFlattener {
    ojson = {}
    flattenedjson = {}

    constructor(original_json) {
        this.ojson = original_json
        this.flattenedjson = {}
        this.flatten()
    }

    flatten() {
        Object.keys(this.ojson).forEach(function(key){
            if (this.ojson[key] == null) {

            } else if (this.ojson[key].constructor == ({}).constructor) {
                this.combine(new JSONFlattener(this.ojson[key]).returnJSON())
            } else {
                this.flattenedjson[key] = this.ojson[key]
            }
        }, this)        
    }

    combine(new_json) {
        //assumes new_json is a flat array
        Object.keys(new_json).forEach(function(key){
            if (!this.flattenedjson.hasOwnProperty(key)) {
                this.flattenedjson[key] = new_json[key]
            } else {
                console.log(key+" is a duplicate key")
            }
        }, this)
    }

    returnJSON() {
        return this.flattenedjson
    }
}

console.log(new JSONFlattener(dad_dictionary).returnJSON())

As an example, it converts

nested_json = {
    "a": {
        "b": {
            "c": {
                "d": {
                    "a": 0
                }
            }
        }
    },
    "z": {
        "b":1
    },
    "d": {
        "c": {
            "c": 2
        }
    }
}

into

{ a: 0, b: 1, c: 2 }

How large should my recv buffer be when calling recv in the socket library

16kb is about right; if you're using gigabit ethernet, each packet could be 9kb in size.

How to get Current Timestamp from Carbon in Laravel 5

With a \ before a Class declaration you are calling the root namespace:

$now = \Carbon\Carbon::now()->timestamp;

otherwise it looks for it at the current namespace declared at the beginning of the class. other solution is to use it:

use Carbon\Carbon
$now = Carbon::now()->timestamp;

you can even assign it an alias:

use Carbon\Carbon as Time;
$now = Time::now()->timestamp;

hope it helps.

How to change font size in a textbox in html

Here are some ways to edit the text and the size of the box:

rows="insertNumber"
cols="insertNumber"
style="font-size:12pt"

Example:

<textarea rows="5" cols="30" style="font-size: 12pt" id="myText">Enter 
Text Here</textarea>

Register DLL file on Windows Server 2008 R2

You need the full path to the regsvr32 so %windir$\system32\regsvr32 <*.dll>

Running Node.Js on Android

I just had a jaw-drop moment - Termux allows you to install NodeJS on an Android device!

It seems to work for a basic Websocket Speed Test I had on hand. The http served by it can be accessed both locally and on the network.

There is a medium post that explains the installation process

Basically: 1. Install termux 2. apt install nodejs 3. node it up!

One restriction I've run into - it seems the shared folders don't have the necessary permissions to install modules. It might just be a file permission thing. The private app storage works just fine.

How to make a div have a fixed size?

<div>
  <img src="whatever it is" class="image-crop">
</div>

 /*mobile code*/
    .image-crop{
      width:100%;
      max-height: auto;
     }
    /*desktop code*/

  @media screen and (min-width: 640px) {
    .image-crop{
       width:100%;
       max-height: 140px;
      }

How do you set a default value for a MySQL Datetime column?

If you set ON UPDATE CURRENT_TIMESTAMP it will take current time when row data update in table.

 CREATE TABLE bar(
        `create_time` TIMESTAMP CURRENT_TIMESTAMP,
        `update_time` TIMESTAMP ON UPDATE CURRENT_TIMESTAMP
    )

Android Firebase, simply get one child object's data

You don't directly read a value. You can set it with .setValue(), but there is no .getValue() on the reference object.

You have to use a listener. If you just want to read the value once, you use ref.addListenerForSingleValueEvent().

Example:

Firebase ref = new Firebase("YOUR-URL-HERE/PATH/TO/YOUR/STUFF");
ref.addListenerForSingleValueEvent(new ValueEventListener() {
   @Override
   public void onDataChange(DataSnapshot dataSnapshot) {
       String value = (String) dataSnapshot.getValue();

       // do your stuff here with value

   }

   @Override
   public void onCancelled(FirebaseError firebaseError) {

   }
});

Source: https://www.firebase.com/docs/android/guide/retrieving-data.html#section-reading-once

python - find index position in list based of partial string

indices = [i for i, s in enumerate(mylist) if 'aa' in s]

Sending POST data without form

You could use AJAX to send a POST request if you don't want forms.

Using jquery $.post method it is pretty simple:

$.post('/foo.php', { key1: 'value1', key2: 'value2' }, function(result) {
    alert('successfully posted key1=value1&key2=value2 to foo.php');
});

How to use mysql JOIN without ON condition?

See some example in http://www.sitepoint.com/understanding-sql-joins-mysql-database/

You can use 'USING' instead of 'ON' as in the query

SELECT * FROM table1 LEFT JOIN table2 USING (id);

What does the arrow operator, '->', do in Java?

New Operator for lambda expression added in java 8

Lambda expression is the short way of method writing.
It is indirectly used to implement functional interface

Primary Syntax : (parameters) -> { statements; }

There are some basic rules for effective lambda expressions writting which you should konw.

How do I execute .js files locally in my browser?

Around 1:51 in the video, notice how she puts a <script> tag in there? The way it works is like this:

Create an html file (that's just a text file with a .html ending) somewhere on your computer. In the same folder that you put index.html, put a javascript file (that's just a textfile with a .js ending - let's call it game.js). Then, in your index.html file, put some html that includes the script tag with game.js, like Mary did in the video. index.html should look something like this:

<html>
    <head>
        <script src="game.js"></script>
    </head>
</html>

Now, double click on that file in finder, and it should open it up in your browser. To open up the console to see the output of your javascript code, hit Command-alt-j (those three buttons at the same time).

Good luck on your journey, hope it's as fun for you as it has been for me so far :)

SQL Query for Student mark functionality

You just have to partition the problem into some bite-sized steps and solve each one by one

First, get the maximum score in each subject:

select SubjectID, max(MarkRate)
from Mark
group by SubjectID;

Then query who are those that has SubjectID with max MarkRate:

select SubjectID, MarkRate, StudentID
from Mark
where (SubjectID,MarkRate)
in
  (
  select SubjectID, max(MarkRate)
  from Mark
  group by SubjectID
  )
order by SubjectID, StudentID;

Then obtain the Student's name, instead of displaying just the StudentID:

select SubjectName, MarkRate, StudentName
from Mark
join Student using(StudentID)
join Subject using(SubjectID)
where (SubjectID,MarkRate)
in
  (
  select SubjectID, max(MarkRate)
  from Mark
  group by SubjectID
  )
order by SubjectName, StudentName

Database vendors' artificial differences aside with regards to joining and correlating results, the basic step is the same; first, partition the problem in a bite-sized parts, and then integrate them as you solved each one of them, so it won't be as confusing.


Sample data:

CREATE TABLE Student
    (StudentID int, StudentName varchar(6), Details varchar(1));    
INSERT INTO Student
    (StudentID, StudentName, Details)
VALUES
    (1, 'John', 'X'),
    (2, 'Paul', 'X'),
    (3, 'George', 'X'),
    (4, 'Paul', 'X');

CREATE TABLE Subject
    (SubjectID varchar(1), SubjectName varchar(7));    
INSERT INTO Subject
    (SubjectID, SubjectName)
VALUES
    ('M', 'Math'),
    ('E', 'English'),
    ('H', 'History');

CREATE TABLE Mark
    (StudentID int, SubjectID varchar(1), MarkRate int);    
INSERT INTO Mark
    (StudentID, SubjectID, MarkRate)
VALUES
    (1, 'M', 90),
    (1, 'E', 100),
    (2, 'M', 95),
    (2, 'E', 70),
    (3, 'E', 95),
    (3, 'H', 98),
    (4, 'H', 90),
    (4, 'E', 100);

Live test here: http://www.sqlfiddle.com/#!1/08728/3


IN tuple test is still a join by any other name:

Convert this..

select SubjectName, MarkRate, StudentName
from Mark
join Student using(StudentID)
join Subject using(SubjectID)

where (SubjectID,MarkRate)
in
  (
  select SubjectID, max(MarkRate)
  from Mark
  group by SubjectID
  )

order by SubjectName, StudentName

..to JOIN:

select SubjectName, MarkRate, StudentName
from Mark
join Student using(StudentID)
join Subject using(SubjectID)

join
  (
  select SubjectID, max(MarkRate) as MarkRate
  from Mark
  group by SubjectID
  ) as x using(SubjectID,MarkRate)

order by SubjectName, StudentName

Contrast this code with the code immediate it. See how JOIN on independent query look like an IN construct? They almost look the same, and IN was just replaced with JOIN keyword; and the replaced IN keyword with JOIN is in fact longer, you need to alias the independent query's column result(max(MarkRate) AS MarkRate) and also the subquery itself (as x). Anyway, this are just matter of style, I prefer IN clause, as the intent is clearer. Using JOINs merely to reflect the data relationship.

Anyway, here's the query that works on all databases that doesn't support tuple test(IN):

select sb.SubjectName, m.MarkRate, st.StudentName
from Mark as m
join Student as st on st.StudentID = m.StudentID
join Subject as sb on sb.SubjectID = m.SubjectID

join
  (
  select SubjectID, max(MarkRate) as MaxMarkRate
  from Mark
  group by SubjectID
  ) as x on m.SubjectID = x.SubjectID AND m.MarkRate = x.MaxMarkRate

order by sb.SubjectName, st.StudentName

Live test: http://www.sqlfiddle.com/#!1/08728/4

Index was out of range. Must be non-negative and less than the size of the collection parameter name:index

This error is caused when you have enabled paging in Grid view. If you want to delete a record from grid then you have to do something like this.

int index = Convert.ToInt32(e.CommandArgument);
int i = index % 20;
// Here 20 is my GridView's Page Size.
GridViewRow row = gvMainGrid.Rows[i];
int id = Convert.ToInt32(gvMainGrid.DataKeys[i].Value);
new GetData().DeleteRecord(id);
GridView1.DataSource = RefreshGrid();
GridView1.DataBind();

Hope this answers the question.

How to send a JSON object using html form data

I found a way to pass a JSON message using only a HTML form.

This example is for GraphQL but it will work for any endpoint that is expecting a JSON message.

GrapqhQL by default expects a parameter called operations where you can add your query or mutation in JSON format. In this specific case I am invoking this query which is requesting to get allUsers and return the userId of each user.

{ 
 allUsers 
  { 
  userId 
  }
}

I am using a text input to demonstrate how to use it, but you can change it for a hidden input to hide the query from the user.

<html>
<body>
    <form method="post" action="http://localhost:8080/graphql">
        <input type="text" name="operations" value="{&quot;query&quot;: &quot;{ allUsers { userId } }&quot;, "variables":  {}}"/>
        <input type="submit" />
    </form>
</body>
</html>

In order to make this dynamic you will need JS to transport the values of the text fields to the query string before submitting your form. Anyway I found this approach very interesting. Hope it helps.

Py_Initialize fails - unable to load the file system codec

I had the same issue and found this question. However from the answers here I was not able to solve my problem. I started debugging the cpython code and thought that I might be discovered a bug. Therefore I opened a issue on the python issue tracker.

My mistake was that I did not understand that Py_SetPath clears all inferred paths. So one needs to set all paths when calling this function.

For completion I also copied the most important part of the conversation below.


My original issue text

I compiled the source of CPython 3.7.3 myself on Windows with Visual Studio 2017 together with some packages like e.g numpy. When I start the Python Interpreter I am able to import and use numpy. However when I am running the same script via the C-API I get an ModuleNotFoundError.

So the first thing I did, was to check if numpy is in my site-packages directory and indeed there is a folder named numpy-1.16.2-py3.7-win-amd64.egg. (Makes sense because the python interpreter can find numpy)

The next thing I did was to get some information about the sys.path variable created when running the script via the C-API.

#### sys.path content ####
C:\Work\build\product\python37.zip
C:\Work\build\product\DLLs
C:\Work\build\product\lib
C:\PROGRAM FILES (X86)\MICROSOFT VISUAL STUDIO\2017\PROFESSIONAL\COMMON7\IDE\EXTENSIONS\TESTPLATFORM
C:\Users\rvq\AppData\Roaming\Python\Python37\site-packages

Examining the content of sys.path I noticed two things.

  1. C:\Work\build\product\python37.zip has the correct path 'C:\Work\build\product\'. There was just no zip file. All my files and directory were unpacked. So I zipped the files to an archive named python37.zip and this resolved the import error.

  2. C:\Users\rvq\AppData\Roaming\Python\Python37\site-packages is wrong it should be C:\Work\build\product\Lib\site-packages but I dont know how this wrong path is created.

The next thing I tried was to use Py_SetPath(L"C:/Work/build/product/Lib/site-packages") before calling Py_Initialize(). This led to

Fatal Python Error 'unable to load the file system encoding' ModuleNotFoundError: No module named 'encodings'

I created a minimal c++ project with exact these two calls and started to debug Cpython.

int main()
{
  Py_SetPath(L"C:/Work/build/product/Lib/site-packages");
  Py_Initialize();
}

I tracked the call of Py_Initialize() down to the call of

static int
zipimport_zipimporter___init___impl(ZipImporter *self, PyObject *path)

inside of zipimport.c

The comment above this function states the following:

Create a new zipimporter instance. 'archivepath' must be a path-like object to a zipfile, or to a specific path inside a zipfile. For example, it can be '/tmp/myimport.zip', or '/tmp/myimport.zip/mydirectory', if mydirectory is a valid directory inside the archive. 'ZipImportError' is raised if 'archivepath' doesn't point to a valid Zip archive. The 'archive' attribute of the zipimporter object contains the name of the zipfile targeted.

So for me it seems that the C-API expects the path set with Py_SetPath to be a path to a zipfile. Is this expected behaviour or is it a bug? If it is not a bug is there a way to changes this so that it can also detect directories?

PS: The ModuleNotFoundError did not occur for me when using Python 3.5.2+, which was the version I used in my project before. I also checked if I had set any PYTHONHOME or PYTHONPATH environment variables but I did not see one of them on my system.


Answer

This is probably a documentation failure more than anything else. We're in the middle of redesigning initialization though, so it's good timing to contribute this feedback.

The short answer is that you need to make sure Python can find the Lib/encodings directory, typically by putting the standard library in sys.path. Py_SetPath clears all inferred paths, so you need to specify all the places Python should look. (The rules for where Python looks automatically are complicated and vary by platform, which is something I'm keen to fix.)

Paths that don't exist are okay, and that's the zip file. You can choose to put the stdlib into a zip, and it will be found automatically if you name it the default path, but you can also leave it unzipped and reference the directory.

A full walk through on embedding is more than I'm prepared to type on my phone. Hopefully that's enough to get you going for now.

Edit a commit message in SourceTree Windows (already pushed to remote)

If the comment message includes non-English characters, using method provided by user456814, those characters will be replaced by question marks. (tested under sourcetree Ver2.5.5.0)

So I have to use the following method.

CAUTION: if the commit has been pulled by other members, changes below might cause chaos for them.

Step1: In the sourcetree main window, locate your repo tab, and click the "terminal" button to open the git command console.

Step2:

[Situation A]: target commit is the latest one.

1) In the git command console, input

git commit --amend -m "new comment message"

2) If the target commit has been pushed to remote, you have to push again by force. In the git command console, input

git push --force

[Situation B]: target commit is not the latest one.

1) In the git command console, input

git rebase -i HEAD~n

It is to squash the latest n commits. e.g. if you want to edit the message before the last one, n is 2. This command will open a vi window, the first word of each line is "pick", and you change the "pick" to "reword" for the line you want to edit. Then, input :wq to save&quit that vi window. Now, a new vi window will be open, in this window you input your new message. Also use :wq to save&quit.

2) If the target commit has been pushed to remote, you have to push again by force. In the git command console, input

git push --force


Finally: In the sourcetree main window, Press F5 to refresh.

Creating temporary files in Android

This is what I typically do:

File outputDir = context.getCacheDir(); // context being the Activity pointer
File outputFile = File.createTempFile("prefix", "extension", outputDir);

As for their deletion, I am not complete sure either. Since I use this in my implementation of a cache, I manually delete the oldest files till the cache directory size comes down to my preset value.

Continuous Integration vs. Continuous Delivery vs. Continuous Deployment

One graph can replace many words:

enter image description here

Enjoy! :-)

# I have updated the correct image...

Excel - extracting data based on another list

I couldn't get the first method to work, and I know this is an old topic, but this is what I ended up doing for a solution:

=IF(ISNA(MATCH(A1,B:B,0)),"Not Matched", A1)

Basically, MATCH A1 to Column B exactly (the 0 stands for match exactly to a value in Column B). ISNA tests for #N/A response which match will return if the no match is found. Finally, if ISNA is true, write "Not Matched" to the selected cell, otherwise write the contents of the matched cell.

Can IntelliJ IDEA encapsulate all of the functionality of WebStorm and PHPStorm through plugins?

Definitely a great question. I've noted this also as a sub question of the choice for versions within IDEa that this link may help to address...

http://www.jetbrains.com/idea/features/editions_comparison_matrix.html

it as well potentially possesses a ground work for looking at your other IDE choices and the options they provide.

I'm thinking WebStorm is best for JavaScript and Git repo management, meaning the HTML5 CSS Cordova kinds of stacks, which is really where (I believe along with others) the future lies and energies should be focused now... but ya it depends on your needs, etc.

Anyway this tells that story too... http://www.jetbrains.com/products.html

Breaking/exit nested for in vb.net

Put the loops in a subroutine and call return

Name [jdbc/mydb] is not bound in this Context

For those who use Tomcat with Bitronix, this will fix the problem:

The error indicates that no handler could be found for your datasource 'jdbc/mydb', so you'll need to make sure your tomcat server refers to your bitronix configuration files as needed.

In case you're using btm-config.properties and resources.properties files to configure the datasource, specify these two JVM arguments in tomcat:

(if you already used them, make sure your references are correct):

  • btm.root
  • bitronix.tm.configuration

e.g.

-Dbtm.root="C:\Program Files\Apache Software Foundation\Tomcat 7.0.59" 
-Dbitronix.tm.configuration="C:\Program Files\Apache Software Foundation\Tomcat 7.0.59\conf\btm-config.properties" 

Now, restart your server and check the log.

How to uncheck checkbox using jQuery Uniform library

A simpler solution is to do this rather than using uniform:

$('#check1').prop('checked', true); // will check the checkbox with id check1
$('#check1').prop('checked', false); // will uncheck the checkbox with id check1

This will not trigger any click action defined.

You can also use:

$('#check1').click(); // 

This will toggle the check/uncheck for the checkbox but this will also trigger any click action you have defined. So be careful.

EDIT: jQuery 1.6+ uses prop() not attr() for checkboxes checked value

ojdbc14.jar vs. ojdbc6.jar

Actually, ojdbc14.jar doesn't really say anything about the real version of the driver (see JDBC Driver Downloads), except that it predates Oracle 11g. In such situation, you should provide the exact version.

Anyway, I think you'll find some explanation in What is going on with DATE and TIMESTAMP? In short, they changed the behavior in 9.2 drivers and then again in 11.1 drivers.

This might explain the differences you're experiencing (and I suggest using the most recent version i.e. the 11.2 drivers).

Expected response code 220 but got code "", with message "" in Laravel

That error message means that there was not response OR the server could not be connected.

The following settings worked on my end:

'stream' => [
        'ssl' => [
            'allow_self_signed' => true,
            'verify_peer' => false,
            'verify_peer_name' => false,
        ],
    ]

Note that my SMTP settings are:

MAIL_DRIVER=smtp
MAIL_HOST=smtp.gmail.com
MAIL_PORT=465
MAIL_USERNAME=[full gmail address]
MAIL_PASSWORD=[App Password obtained after two step verification]
MAIL_ENCRYPTION=ssl

Could not find server 'server name' in sys.servers. SQL Server 2014

I figured out the issue. The linked server was created correctly. However, after the server was upgraded and switched the server name in sys.servers still had the old server name.

I had to drop the old server name and add the new server name to sys.servers on the new server

sp_dropserver 'Server_A'
GO
sp_addserver  'Server',local
GO

Keyboard shortcut to comment lines in Sublime Text 3

I prefer pressing Ctrl + / to (un)comment the current line. Plus, I want the cursor to move down one line, thus this way I can (un)comment several lines easily. If you install the "Chain of Command" plugin, you can combine these two operations:

[
    { 
        "keys": ["ctrl+keypad_divide"], 
        "command": "chain",
        "args": {
            "commands": [
                ["toggle_comment", { "block": false }],
                ["move", {"by": "lines", "forward": true}]
            ]
        }
    }
]

Any way to exit bash script, but not quitting the terminal

Actually, I think you might be confused by how you should run a script.

If you use sh to run a script, say, sh ./run2.sh, even if the embedded script ends with exit, your terminal window will still remain.

However if you use . or source, your terminal window will exit/close as well when subscript ends.

for more detail, please refer to What is the difference between using sh and source?

Retrieve a Fragment from a ViewPager

in TabLayout there are multiple tab for Fragment. you can find the fragment by Tag using the index of the fragment.

For ex. the index for Fragment1 is 0, so in findFragmentByTag() method, pass the tag for the Viewpager.after using fragmentTransaction you can add,replace the fragment.

String tag = "android:switcher:" + R.id.viewPager + ":" + 0; Fragment1 f = (Fragment1) getSupportFragmentManager().findFragmentByTag(tag);

How to filter an array of objects based on values in an inner array with jq?

Here is another solution which uses any/2

map(select(any(.Names[]; contains("data"))|not)|.Id)[]

with the sample data and the -r option it produces

cb94e7a42732b598ad18a8f27454a886c1aa8bbba6167646d8f064cd86191e2b
a4b7e6f5752d8dcb906a5901f7ab82e403b9dff4eaaeebea767a04bac4aada19

When do I need to do "git pull", before or after "git add, git commit"?

Best way for me is:

  1. create new branch, checkout to it
  2. create or modify files, git add, git commit
  3. back to master branch and do pull from remote (to get latest master changes)
  4. merge newly created branch with master
  5. remove newly created branch
  6. push master to remote

Or you can push newly created branch on remote and merge there (if you do it this way, at the end you need to pull from remote master)

converting multiple columns from character to numeric format in r

You could try

DF <- data.frame("a" = as.character(0:5),
                 "b" = paste(0:5, ".1", sep = ""),
                 "c" = letters[1:6],
                 stringsAsFactors = FALSE)

# Check columns classes
sapply(DF, class)

#           a           b           c 
# "character" "character" "character" 

cols.num <- c("a","b")
DF[cols.num] <- sapply(DF[cols.num],as.numeric)
sapply(DF, class)

#          a           b           c 
#  "numeric"   "numeric" "character"

Oracle query execution time

Use:

set serveroutput on
variable n number
exec :n := dbms_utility.get_time;
select ......
exec dbms_output.put_line( (dbms_utility.get_time-:n)/100) || ' seconds....' );

Or possibly:

SET TIMING ON;

-- do stuff

SET TIMING OFF;

...to get the hundredths of seconds that elapsed.

In either case, time elapsed can be impacted by server load/etc.

Reference:

Easy login script without database

You can do the access control at the Web server level using HTTP Basic authentication and htpasswd. There are a number of problems with this:

  1. It's not very secure (username and password are trivially encoded on the wire)
  2. It's difficult to maintain (you have to log into the server to add or remove users)
  3. You have no control over the login dialog box presented by the browser
  4. There is no way of logging out, short of restarting the browser.

Unless you're building a site for internal use with few users, I wouldn't really recommend it.

Git: How to commit a manually deleted file?

Use git add -A, this will include the deleted files.

Note: use git rm for certain files.

Remove large .pack file created by git

this is more of a handy solution than a coding one. zip the file. Open the zip in file view format (different from unzipping). Delete the .pack file. Unzip and replace the folder. Works like a charm!

Angular 2 Routing run in new tab

Try this please, <a target="_blank" routerLink="/Page2">


Update1: Custom directives to the rescue! Full code is here: https://github.com/pokearound/angular2-olnw

import { Directive, ElementRef, HostListener, Input, Inject } from '@angular/core';

@Directive({ selector: '[olinw007]' })
export class OpenLinkInNewWindowDirective {
    //@Input('olinwLink') link: string; //intro a new attribute, if independent from routerLink
    @Input('routerLink') link: string;
    constructor(private el: ElementRef, @Inject(Window) private win:Window) {
    }
    @HostListener('mousedown') onMouseEnter() {
        this.win.open(this.link || 'main/default');
    }
}

Notice, Window is provided and OpenLinkInNewWindowDirective declared below:

import { AppAboutComponent } from './app.about.component';
import { AppDefaultComponent } from './app.default.component';
import { PageNotFoundComponent } from './app.pnf.component';
import { OpenLinkInNewWindowDirective } from './olinw.directive';
import { BrowserModule } from '@angular/platform-browser';
import { NgModule } from '@angular/core';
import { FormsModule } from '@angular/forms';
import { HttpModule } from '@angular/http';
import { RouterModule, Routes } from '@angular/router';

import { AppComponent } from './app.component';


const appRoutes: Routes = [
  { path: '', pathMatch: 'full', component: AppDefaultComponent },
  { path: 'home', component: AppComponent },
  { path: 'about', component: AppAboutComponent },
  { path: '**', component: PageNotFoundComponent }
];

@NgModule({
  declarations: [
    AppComponent, AppAboutComponent, AppDefaultComponent, PageNotFoundComponent, OpenLinkInNewWindowDirective
  ],
  imports: [
    BrowserModule,
    FormsModule,
    HttpModule,
    RouterModule.forRoot(appRoutes)
  ],
  providers: [{ provide: Window, useValue: window }],
  bootstrap: [AppComponent]
})
export class AppModule { }

First link opens in new Window, second one will not:

<h1>
    {{title}}
    <ul>
        <li><a routerLink="/main/home" routerLinkActive="active" olinw007> OLNW</a></li>
        <li><a routerLink="/main/home" routerLinkActive="active"> OLNW - NOT</a></li>
    </ul>
    <div style="background-color:#eee;">
        <router-outlet></router-outlet>
    </div>
</h1>

Tada! ..and you are welcome =)

Update2: As of v2.4.10 <a target="_blank" routerLink="/Page2"> works

eslint: error Parsing error: The keyword 'const' is reserved

If using Visual Code one option is to add this to the settings.json file:

"eslint.options": {
    "useEslintrc": false,
    "parserOptions": {
        "ecmaVersion": 2017
    },
    "env": {
        "es6": true
    }
}

How can I align button in Center or right using IONIC framework?

And if we want to align a checkbox to the right, we can use item-end.

<ion-checkbox checked="true" item-end></ion-checkbox>

How to save an image locally using Python whose URL address I already know?

Using requests library

import requests
import shutil,os

headers = {
    'user-agent': 'Mozilla/5.0 (Windows NT 10.0; Win64; x64) AppleWebKit/537.36 (KHTML, like Gecko) Chrome/78.0.3904.108 Safari/537.36'
}
currentDir = os.getcwd()
path = os.path.join(currentDir,'Images')#saving images to Images folder

def ImageDl(url):
    attempts = 0
    while attempts < 5:#retry 5 times
        try:
            filename = url.split('/')[-1]
            r = requests.get(url,headers=headers,stream=True,timeout=5)
            if r.status_code == 200:
                with open(os.path.join(path,filename),'wb') as f:
                    r.raw.decode_content = True
                    shutil.copyfileobj(r.raw,f)
            print(filename)
            break
        except Exception as e:
            attempts+=1
            print(e)


ImageDl(url)

Get a list of resources from classpath directory

Here is the code
Source: forums.devx.com/showthread.php?t=153784

import java.io.File;
import java.io.IOException;
import java.util.ArrayList;
import java.util.Collection;
import java.util.Enumeration;
import java.util.regex.Pattern;
import java.util.zip.ZipEntry;
import java.util.zip.ZipException;
import java.util.zip.ZipFile;

/**
 * list resources available from the classpath @ *
 */
public class ResourceList{

    /**
     * for all elements of java.class.path get a Collection of resources Pattern
     * pattern = Pattern.compile(".*"); gets all resources
     * 
     * @param pattern
     *            the pattern to match
     * @return the resources in the order they are found
     */
    public static Collection<String> getResources(
        final Pattern pattern){
        final ArrayList<String> retval = new ArrayList<String>();
        final String classPath = System.getProperty("java.class.path", ".");
        final String[] classPathElements = classPath.split(System.getProperty("path.separator"));
        for(final String element : classPathElements){
            retval.addAll(getResources(element, pattern));
        }
        return retval;
    }

    private static Collection<String> getResources(
        final String element,
        final Pattern pattern){
        final ArrayList<String> retval = new ArrayList<String>();
        final File file = new File(element);
        if(file.isDirectory()){
            retval.addAll(getResourcesFromDirectory(file, pattern));
        } else{
            retval.addAll(getResourcesFromJarFile(file, pattern));
        }
        return retval;
    }

    private static Collection<String> getResourcesFromJarFile(
        final File file,
        final Pattern pattern){
        final ArrayList<String> retval = new ArrayList<String>();
        ZipFile zf;
        try{
            zf = new ZipFile(file);
        } catch(final ZipException e){
            throw new Error(e);
        } catch(final IOException e){
            throw new Error(e);
        }
        final Enumeration e = zf.entries();
        while(e.hasMoreElements()){
            final ZipEntry ze = (ZipEntry) e.nextElement();
            final String fileName = ze.getName();
            final boolean accept = pattern.matcher(fileName).matches();
            if(accept){
                retval.add(fileName);
            }
        }
        try{
            zf.close();
        } catch(final IOException e1){
            throw new Error(e1);
        }
        return retval;
    }

    private static Collection<String> getResourcesFromDirectory(
        final File directory,
        final Pattern pattern){
        final ArrayList<String> retval = new ArrayList<String>();
        final File[] fileList = directory.listFiles();
        for(final File file : fileList){
            if(file.isDirectory()){
                retval.addAll(getResourcesFromDirectory(file, pattern));
            } else{
                try{
                    final String fileName = file.getCanonicalPath();
                    final boolean accept = pattern.matcher(fileName).matches();
                    if(accept){
                        retval.add(fileName);
                    }
                } catch(final IOException e){
                    throw new Error(e);
                }
            }
        }
        return retval;
    }

    /**
     * list the resources that match args[0]
     * 
     * @param args
     *            args[0] is the pattern to match, or list all resources if
     *            there are no args
     */
    public static void main(final String[] args){
        Pattern pattern;
        if(args.length < 1){
            pattern = Pattern.compile(".*");
        } else{
            pattern = Pattern.compile(args[0]);
        }
        final Collection<String> list = ResourceList.getResources(pattern);
        for(final String name : list){
            System.out.println(name);
        }
    }
}  

If you are using Spring Have a look at PathMatchingResourcePatternResolver

intellij incorrectly saying no beans of type found for autowired repository

My solution to this issue in my spring boot application was to open the spring application context and adding the class for the missing autowired bean manually!

(access via Project Structure menu or spring tool window... edit "Spring Application Context")

So instead of SpringApplicationContext just containing my ExampleApplication spring configuration it also contains the missing Bean:

SpringApplicationContext:

  • ExampleApplication.java
  • MissingBeanClass.java

et voilà: The error message disappeared!

The most accurate way to check JS object's type?

I'd argue that most of the solutions shown here suffer from being over-engineerd. Probably the most simple way to check if a value is of type [object Object] is to check against the .constructor property of it:

function isObject (a) { return a != null && a.constructor === Object; }

or even shorter with arrow-functions:

const isObject = a => a != null && a.constructor === Object;

The a != null part is necessary because one might pass in null or undefined and you cannot extract a constructor property from either of these.

It works with any object created via:

  • the Object constructor
  • literals {}

Another neat feature of it, is it's ability to give correct reports for custom classes which make use of Symbol.toStringTag. For example:

class MimicObject {
  get [Symbol.toStringTag]() {
    return 'Object';
  }
}

The problem here is that when calling Object.prototype.toString on an instance of it, the false report [object Object] will be returned:

let fakeObj = new MimicObject();
Object.prototype.toString.call(fakeObj); // -> [object Object]

But checking against the constructor gives a correct result:

let fakeObj = new MimicObject();
fakeObj.constructor === Object; // -> false

Disabling Chrome Autofill

None of the solutions worked for me. Finally, after pulling my hair out for many hours I came up with this solution for ReactJS.

Tested on FireFox 54.0.1, Chrome 61.0.3163.100, Mac OS 10.13

I keep the type="text" and change it to relevant type on onChange event.

ex: HTML:

<input type="text" onChange={this.setAttributes} placeholder="Email" />

JS:

setAttr2: function(e){
    var value = e.target.value;
    if(value.length){
      e.target.setAttribute('type', 'email')
    } else {
      e.target.setAttribute('type', 'text')
    }
  }

Create whole path automatically when writing to a new file

Something like:

File file = new File("C:\\user\\Desktop\\dir1\\dir2\\filename.txt");
file.getParentFile().mkdirs();
FileWriter writer = new FileWriter(file);

How do I pass a unique_ptr argument to a constructor or a function?

Edit: This answer is wrong, even though, strictly speaking, the code works. I'm only leaving it here because the discussion under it is too useful. This other answer is the best answer given at the time I last edited this: How do I pass a unique_ptr argument to a constructor or a function?

The basic idea of ::std::move is that people who are passing you the unique_ptr should be using it to express the knowledge that they know the unique_ptr they're passing in will lose ownership.

This means you should be using an rvalue reference to a unique_ptr in your methods, not a unique_ptr itself. This won't work anyway because passing in a plain old unique_ptr would require making a copy, and that's explicitly forbidden in the interface for unique_ptr. Interestingly enough, using a named rvalue reference turns it back into an lvalue again, so you need to use ::std::move inside your methods as well.

This means your two methods should look like this:

Base(Base::UPtr &&n) : next(::std::move(n)) {} // Spaces for readability

void setNext(Base::UPtr &&n) { next = ::std::move(n); }

Then people using the methods would do this:

Base::UPtr objptr{ new Base; }
Base::UPtr objptr2{ new Base; }
Base fred(::std::move(objptr)); // objptr now loses ownership
fred.setNext(::std::move(objptr2)); // objptr2 now loses ownership

As you see, the ::std::move expresses that the pointer is going to lose ownership at the point where it's most relevant and helpful to know. If this happened invisibly, it would be very confusing for people using your class to have objptr suddenly lose ownership for no readily apparent reason.

How to print a string multiple times?

for i in range(3):
    print "Your text here"

Or

for i in range(3):
    print("Your text here")

LogisticRegression: Unknown label type: 'continuous' using sklearn in python

I struggled with the same issue when trying to feed floats to the classifiers. I wanted to keep floats and not integers for accuracy. Try using regressor algorithms. For example:

import numpy as np
from sklearn import linear_model
from sklearn import svm

classifiers = [
    svm.SVR(),
    linear_model.SGDRegressor(),
    linear_model.BayesianRidge(),
    linear_model.LassoLars(),
    linear_model.ARDRegression(),
    linear_model.PassiveAggressiveRegressor(),
    linear_model.TheilSenRegressor(),
    linear_model.LinearRegression()]

trainingData    = np.array([ [2.3, 4.3, 2.5],  [1.3, 5.2, 5.2],  [3.3, 2.9, 0.8],  [3.1, 4.3, 4.0]  ])
trainingScores  = np.array( [3.4, 7.5, 4.5, 1.6] )
predictionData  = np.array([ [2.5, 2.4, 2.7],  [2.7, 3.2, 1.2] ])

for item in classifiers:
    print(item)
    clf = item
    clf.fit(trainingData, trainingScores)
    print(clf.predict(predictionData),'\n')