Programs & Examples On #Interfacing

Converting between java.time.LocalDateTime and java.util.Date

Everything is here : http://blog.progs.be/542/date-to-java-time

The answer with "round-tripping" is not exact : when you do

LocalDateTime ldt = LocalDateTime.ofInstant(instant, ZoneOffset.UTC);

if your system timezone is not UTC/GMT, you change the time !

C# with MySQL INSERT parameters

comm.Parameters.Add("person", "Myname");

Java abstract interface

Why is it necessary for an interface to be "declared" abstract?

It's not.

public abstract interface Interface {
       \___.__/
           |
           '----> Neither this...

    public void interfacing();
    public abstract boolean interfacing(boolean really);
           \___.__/
               |
               '----> nor this, are necessary.
}

Interfaces and their methods are implicitly abstract and adding that modifier makes no difference.

Is there other rules that applies with an abstract interface?

No, same rules apply. The method must be implemented by any (concrete) implementing class.

If abstract is obsolete, why is it included in Java? Is there a history for abstract interface?

Interesting question. I dug up the first edition of JLS, and even there it says "This modifier is obsolete and should not be used in new Java programs".

Okay, digging even further... After hitting numerous broken links, I managed to find a copy of the original Oak 0.2 Specification (or "manual"). Quite interesting read I must say, and only 38 pages in total! :-)

Under Section 5, Interfaces, it provides the following example:

public interface Storing {
    void freezeDry(Stream s) = 0;
    void reconstitute(Stream s) = 0;
}

And in the margin it says

In the future, the " =0" part of declaring methods in interfaces may go away.

Assuming =0 got replaced by the abstract keyword, I suspect that abstract was at some point mandatory for interface methods!


Related article: Java: Abstract interfaces and abstract interface methods

Get name of current class?

Within the body of a class, the class name isn't defined yet, so it is not available. Can you not simply type the name of the class? Maybe you need to say more about the problem so we can find a solution for you.

I would create a metaclass to do this work for you. It's invoked at class creation time (conceptually at the very end of the class: block), and can manipulate the class being created. I haven't tested this:

class InputAssigningMetaclass(type):
    def __new__(cls, name, bases, attrs):
        cls.input = get_input(name)
        return super(MyType, cls).__new__(cls, name, bases, newattrs)

class MyBaseFoo(object):
    __metaclass__ = InputAssigningMetaclass

class foo(MyBaseFoo):
    # etc, no need to create 'input'

class foo2(MyBaseFoo):
    # etc, no need to create 'input'

How do you execute an arbitrary native command from a string?

If you want to use the call operator, the arguments can be an array stored in a variable:

$prog = 'c:\windows\system32\cmd.exe'
$myargs = '/c','dir','/x'
& $prog $myargs

The call operator works with ApplicationInfo objects too.

$prog = get-command cmd
$myargs = -split '/c dir /x'
& $prog $myargs

Using HTML5 file uploads with AJAX and jQuery

With jQuery (and without FormData API) you can use something like this:

function readFile(file){
   var loader = new FileReader();
   var def = $.Deferred(), promise = def.promise();

   //--- provide classic deferred interface
   loader.onload = function (e) { def.resolve(e.target.result); };
   loader.onprogress = loader.onloadstart = function (e) { def.notify(e); };
   loader.onerror = loader.onabort = function (e) { def.reject(e); };
   promise.abort = function () { return loader.abort.apply(loader, arguments); };

   loader.readAsBinaryString(file);

   return promise;
}

function upload(url, data){
    var def = $.Deferred(), promise = def.promise();
    var mul = buildMultipart(data);
    var req = $.ajax({
        url: url,
        data: mul.data,
        processData: false,
        type: "post",
        async: true,
        contentType: "multipart/form-data; boundary="+mul.bound,
        xhr: function() {
            var xhr = jQuery.ajaxSettings.xhr();
            if (xhr.upload) {

                xhr.upload.addEventListener('progress', function(event) {
                    var percent = 0;
                    var position = event.loaded || event.position; /*event.position is deprecated*/
                    var total = event.total;
                    if (event.lengthComputable) {
                        percent = Math.ceil(position / total * 100);
                        def.notify(percent);
                    }                    
                }, false);
            }
            return xhr;
        }
    });
    req.done(function(){ def.resolve.apply(def, arguments); })
       .fail(function(){ def.reject.apply(def, arguments); });

    promise.abort = function(){ return req.abort.apply(req, arguments); }

    return promise;
}

var buildMultipart = function(data){
    var key, crunks = [], bound = false;
    while (!bound) {
        bound = $.md5 ? $.md5(new Date().valueOf()) : (new Date().valueOf());
        for (key in data) if (~data[key].indexOf(bound)) { bound = false; continue; }
    }

    for (var key = 0, l = data.length; key < l; key++){
        if (typeof(data[key].value) !== "string") {
            crunks.push("--"+bound+"\r\n"+
                "Content-Disposition: form-data; name=\""+data[key].name+"\"; filename=\""+data[key].value[1]+"\"\r\n"+
                "Content-Type: application/octet-stream\r\n"+
                "Content-Transfer-Encoding: binary\r\n\r\n"+
                data[key].value[0]);
        }else{
            crunks.push("--"+bound+"\r\n"+
                "Content-Disposition: form-data; name=\""+data[key].name+"\"\r\n\r\n"+
                data[key].value);
        }
    }

    return {
        bound: bound,
        data: crunks.join("\r\n")+"\r\n--"+bound+"--"
    };
};

//----------
//---------- On submit form:
var form = $("form");
var $file = form.find("#file");
readFile($file[0].files[0]).done(function(fileData){
   var formData = form.find(":input:not('#file')").serializeArray();
   formData.file = [fileData, $file[0].files[0].name];
   upload(form.attr("action"), formData).done(function(){ alert("successfully uploaded!"); });
});

With FormData API you just have to add all fields of your form to FormData object and send it via $.ajax({ url: url, data: formData, processData: false, contentType: false, type:"POST"})

What is Common Gateway Interface (CGI)?

What exactly is CGI?

A means for a web server to get its data from a program (instead of, for instance, a file).

Whats the big deal with /cgi-bin/*.cgi?

No big deal. It is just a convention.

I don't know what is this cgi-bin directory on the server for. I don't know why they have *.cgi extensions.

The server has to know what to do with the file (i.e. treat it as a program to execute instead of something to simply serve up). Having a .html extension tells it to use a text/html content type. Having a .cgi extension tells it to run it as a program.

Keeping executables in a separate directory gives some added protection against executing incorrect files and/or serving up CGI programs as raw data in case the server gets misconfigured.

Why does Perl always comes in the way.

It doesn't. Perl was just big and popular at the same time as CGI.

I haven't used Perl CGI for years. I was using mod_perl for a long time, and tend towards PSGI/Plack with FastCGI these days.

This book is another great example CGI Programming with Perl Why not "CGI Programming with PHP/JSP/ASP".

CGI isn't very efficient. Better methods for talking to programs from webservers came along at around the same time as PHP. JSP and ASP are different methods for talking to programs.

CGI Programming in C this confuses me a lot. in C?? Seriously??

It is a programming language, why not?

When do I compile?

  1. Write code
  2. Compile
  3. Access URL
  4. Webserver runs program

How does the program gets executed (because it will be a machine code, so it must execute as a independent process).

It doesn't have to execute as an independent process (you can write Apache modules in C), but the whole concept of CGI is that it launches an external process.

How does it communicate with the web server? IPC?

STDIN/STDOUT and environment variables — as defined in the CGI specification.

and interfacing with all the servers (in my example MATLAB & MySQL) using socket programming?

Using whatever methods you like and are supported.

They say that CGI is depreciated. Its no more in use. Is it so?

CGI is inefficient, slow and simple. It is rarely used, when it is used, it is because it is simple. If performance isn't a big deal, then simplicity is worth a lot.

What is its latest update?

1.1

Mythical man month 10 lines per developer day - how close on large projects?

One suspects this perennial bit of manager-candy was coined when everything was a sys app written in C because if nothing else the magic number would vary by orders of magnitude depending on the language, scale and nature of the application. And then you have to discount comments and attributes. And ultimately who cares about the number of lines of code written? Are you supposed to be finished when you've reach 10K lines? 100K? So arbitrary.

It's useless.

How do I merge a git tag onto a branch

Remember before you merge you need to update the tag, it's quite different from branches (git pull origin tag_name won't update your local tags). Thus, you need the following command:

git fetch --tags origin

Then you can perform git merge tag_name to merge the tag onto a branch.

error: expected class-name before ‘{’ token

Replace

#include "Landing.h"

with

class Landing;

If you still get errors, also post Item.h, Flight.h and common.h

EDIT: In response to comment.

You will need to e.g. #include "Landing.h" from Event.cpp in order to actually use the class. You just cannot include it from Event.h

Best way to create enum of strings?

Depending on what you mean by "use them as Strings", you might not want to use an enum here. In most cases, the solution proposed by The Elite Gentleman will allow you to use them through their toString-methods, e.g. in System.out.println(STRING_ONE) or String s = "Hello "+STRING_TWO, but when you really need Strings (e.g. STRING_ONE.toLowerCase()), you might prefer defining them as constants:

public interface Strings{
  public static final String STRING_ONE = "ONE";
  public static final String STRING_TWO = "TWO";      
}

How to insert a row in an HTML table body in JavaScript

You can use the following example:

<table id="purches">
    <thead>
        <tr>
            <th>ID</th>
            <th>Transaction Date</th>
            <th>Category</th>
            <th>Transaction Amount</th>
            <th>Offer</th>
        </tr>
    </thead>

    <!--  <tr th:each="person: ${list}"    >
            <td><li th:each="person: ${list}" th:text="|${person.description}|"></li></td>
            <td><li th:each="person: ${list}" th:text="|${person.price}|"></li></td>
            <td><li th:each="person: ${list}" th:text="|${person.available}|"></li></td>
            <td><li th:each="person: ${list}" th:text="|${person.from}|"></li></td>
            </tr>
    -->

    <tbody id="feedback">
    </tbody>
</table>

JavaScript file:

$.ajax({
    type: "POST",
    contentType: "application/json",
    url: "/search",
    data: JSON.stringify(search),
    dataType: 'json',
    cache: false,
    timeout: 600000,
    success: function (data) {
        //  var json = "<h4>Ajax Response</h4><pre>"  + JSON.stringify(data, null, 4) + "</pre>";
        // $('#feedback').html(json);
        //
        console.log("SUCCESS: ", data);
        //$("#btn-search").prop("disabled", false);

        for (var i = 0; i < data.length; i++) {
            //$("#feedback").append('<tr><td>' + data[i].accountNumber + '</td><td>' + data[i].category + '</td><td>' + data[i].ssn + '</td></tr>');
            $('#feedback').append('<tr><td>' + data[i].accountNumber + '</td><td>' + data[i].category + '</td><td>' + data[i].ssn + '</td><td>' + data[i].ssn + '</td><td>' + data[i].ssn + '</td></tr>');

            alert(data[i].accountNumber)
        }
    },
    error: function (e) {
        var json = "<h4>Ajax Response</h4><pre>" + e.responseText + "</pre>";
        $('#feedback').html(json);

        console.log("ERROR: ", e);
        $("#btn-search").prop("disabled", false);
    }
});

PowerShell to remove text from a string

This should do what you want:

C:\PS> if ('=keep this,' -match '=([^,]*)') { $matches[1] }
keep this

How do you create nested dict in Python?

It is important to remember when using defaultdict and similar nested dict modules such as nested_dict, that looking up a nonexistent key may inadvertently create a new key entry in the dict and cause a lot of havoc.

Here is a Python3 example with nested_dict module:

import nested_dict as nd
nest = nd.nested_dict()
nest['outer1']['inner1'] = 'v11'
nest['outer1']['inner2'] = 'v12'
print('original nested dict: \n', nest)
try:
    nest['outer1']['wrong_key1']
except KeyError as e:
    print('exception missing key', e)
print('nested dict after lookup with missing key.  no exception raised:\n', nest)

# Instead, convert back to normal dict...
nest_d = nest.to_dict(nest)
try:
    print('converted to normal dict. Trying to lookup Wrong_key2')
    nest_d['outer1']['wrong_key2']
except KeyError as e:
    print('exception missing key', e)
else:
    print(' no exception raised:\n')

# ...or use dict.keys to check if key in nested dict
print('checking with dict.keys')
print(list(nest['outer1'].keys()))
if 'wrong_key3' in list(nest.keys()):

    print('found wrong_key3')
else:
    print(' did not find wrong_key3')

Output is:

original nested dict:   {"outer1": {"inner2": "v12", "inner1": "v11"}}

nested dict after lookup with missing key.  no exception raised:  
{"outer1": {"wrong_key1": {}, "inner2": "v12", "inner1": "v11"}} 

converted to normal dict. 
Trying to lookup Wrong_key2 

exception missing key 'wrong_key2' 

checking with dict.keys 

['wrong_key1', 'inner2', 'inner1']  
did not find wrong_key3

How can I know if a branch has been already merged into master?

You can use the git merge-base command to find the latest common commit between the two branches. If that commit is the same as your branch head, then the branch has been completely merged.

Note that git branch -d does this sort of thing already because it will refuse to delete a branch that hasn't already been completely merged.

What are the lengths of Location Coordinates, latitude and longitude?

Please check the UTM coordinate system https://en.wikipedia.org/wiki/Universal_Transverse_Mercator_coordinate_system.

These values must be in meters for a specific map projection. For example, the peak of Mount Assiniboine (at 50°52'10"N 115°39'03"W) in UTM Zone 11 is represented by 11U 594934.108296 5636174.091274 where (594934.108296, 5636174.091274) are in meters.

Cannot enqueue Handshake after invoking quit

AWS Lambda functions

Use mysql.createPool() with connection.destroy()

This way, new invocations use the established pool, but don't keep the function running. Even though you don't get the full benefit of pooling (each new connection uses a new connection instead of an existing one), it makes it so that a second invocation can establish a new connection without the previous one having to be closed first.

Regarding connection.end()

This can cause a subsequent invocation to throw an error. The invocation will still retry later and work, but with a delay.

Regarding mysql.createPool() with connection.release()

The Lambda function will keep running until the scheduled timeout, as there is still an open connection.

Code example

const mysql = require('mysql');

const pool = mysql.createPool({
  connectionLimit: 100,
  host:     process.env.DATABASE_HOST,
  user:     process.env.DATABASE_USER,
  password: process.env.DATABASE_PASSWORD,
});

exports.handler = (event) => {
  pool.getConnection((error, connection) => {
    if (error) throw error;
    connection.query(`
      INSERT INTO table_name (event) VALUES ('${event}')
    `, function(error, results, fields) {
      if (error) throw error;
      connection.destroy();
    });
  });
};

What is the difference between "Rollback..." and "Back Out Submitted Changelist #####" in Perforce P4V

I explain this to users by comparing Perforce changelists to a stack (from data structures).

Backing out removes one item from anywhere in the stack.

Rolling back removes n items from the top of the stack.

Angular 2 - Redirect to an external URL and open in a new tab

I want to share with you one more solution if you have absolute part in the URL

SharePoint solution with ${_spPageContextInfo.webAbsoluteUrl}

HTML:

<button (click)="onNavigate()">Google</button>

TypeScript:

onNavigate()
{
    let link = `${_spPageContextInfo.webAbsoluteUrl}/SiteAssets/Pages/help.aspx#/help`;
    window.open(link, "_blank");
}

and url will be opened in new tab.

Getting attribute of element in ng-click function in angularjs

Addition to the answer of Brett DeWoody: (which is updated now)

var dataValue = obj.srcElement.attributes.data.nodeValue;

Works fine in IE(9+) and Chrome, but Firefox does not know the srcElement property. I found:

var dataValue = obj.currentTarget.attributes.data.nodeValue;

Works in IE, Chrome and FF, I did not test Safari.

Replace a string in shell script using a variable

echo $LINE | sed -e 's/12345678/'$replace'/g'

you can still use single quotes, but you have to "open" them when you want the variable expanded at the right place. otherwise the string is taken "literally" (as @paxdiablo correctly stated, his answer is correct as well)

What's the difference between Thread start() and Runnable run()

In the first case you are just invoking the run() method of the r1 and r2 objects.

In the second case you're actually creating 2 new Threads!

start() will call run() at some point!

What is the difference between active and passive FTP?

Active and passive are the two modes that FTP can run in.

For background, FTP actually uses two channels between client and server, the command and data channels, which are actually separate TCP connections.

The command channel is for commands and responses while the data channel is for actually transferring files.

This separation of command information and data into separate channels a nifty way of being able to send commands to the server without having to wait for the current data transfer to finish. As per the RFC, this is only mandated for a subset of commands, such as quitting, aborting the current transfer, and getting the status.


In active mode, the client establishes the command channel but the server is responsible for establishing the data channel. This can actually be a problem if, for example, the client machine is protected by firewalls and will not allow unauthorised session requests from external parties.

In passive mode, the client establishes both channels. We already know it establishes the command channel in active mode and it does the same here.

However, it then requests the server (on the command channel) to start listening on a port (at the servers discretion) rather than trying to establish a connection back to the client.

As part of this, the server also returns to the client the port number it has selected to listen on, so that the client knows how to connect to it.

Once the client knows that, it can then successfully create the data channel and continue.

More details are available in the RFC: https://www.ietf.org/rfc/rfc959.txt

How to print a linebreak in a python function?

The newline character is actually '\n'.

jQuery: How to detect window width on the fly?

I dont know if this useful for you when you resize your page:

$(window).resize(function() {
       if(screen.width == window.innerWidth){
           alert("you are on normal page with 100% zoom");
       } else if(screen.width > window.innerWidth){
           alert("you have zoomed in the page i.e more than 100%");
       } else {
           alert("you have zoomed out i.e less than 100%");
       }
    });

How to compare different branches in Visual Studio Code

2019 answer

Here is the step by step guide:

  1. Install the GitLens extension: GitLens
  2. The GitLens icon will show up in nav bar. Click on it.

    Git lens icon

  3. Click on compare

    Enter image description here

  4. Select branches to compare

    enter image description here

  5. Now you can see the difference. You can select any file for which you want to see the diff for.

    Enter image description here

How do I print colored output with Python 3?

It is very simple with colorama, just do this:

import colorama
from colorama import Fore, Style
print(Fore.BLUE + "Hello World")

And here is the running result in Python3 REPL:

And call this to reset the color settings:

print(Style.RESET_ALL)

To avoid printing an empty line write this:

print(f"{Fore.BLUE}Hello World{Style.RESET_ALL}")

A CSS selector to get last visible div

If you no longer need the hided elements, just use element.remove() instead of element.style.display = 'none';.

How to create a pulse effect using -webkit-animation - outward rings

You have a lot of unnecessary keyframes. Don't think of keyframes as individual frames, think of them as "steps" in your animation and the computer fills in the frames between the keyframes.

Here is a solution that cleans up a lot of code and makes the animation start from the center:

.gps_ring {
    border: 3px solid #999;
    -webkit-border-radius: 30px;
    height: 18px;
    width: 18px;
    position: absolute;
    left:20px;
    top:214px;
    -webkit-animation: pulsate 1s ease-out;
    -webkit-animation-iteration-count: infinite; 
    opacity: 0.0
}
@-webkit-keyframes pulsate {
    0% {-webkit-transform: scale(0.1, 0.1); opacity: 0.0;}
    50% {opacity: 1.0;}
    100% {-webkit-transform: scale(1.2, 1.2); opacity: 0.0;}
}

You can see it in action here: http://jsfiddle.net/Fy8vD/

java.lang.NullPointerException: Attempt to invoke virtual method 'int android.view.View.getImportantForAccessibility()' on a null object reference

in your baseadapter class constructor try to initialize LayoutInflater, normally i preferred this way,

public ClassBaseAdapter(Context context,ArrayList<Integer> listLoanAmount) {
    this.context = context;
    this.listLoanAmount = listLoanAmount;
    this.layoutInflater = LayoutInflater.from(context);
}

at the top of the class create LayoutInflater variable, hope this will help you

How to make HTML code inactive with comments

Behold HTML comments:

<!-- comment -->

http://www.w3.org/TR/html401/intro/sgmltut.html#idx-HTML

The proper way to delete code without deleting it, of course, is to use version control, which enables you to resurrect old code from the past. Don't get into the habit of accumulating commented-out code in your pages, it's no fun. :)

Free Rest API to retrieve current datetime as string (timezone irrelevant)

If you're using Rails, you can just make an empty file in the public folder and use ajax to get that. Then parse the headers for the Date header. Files in the Public folder bypass the Rails stack, and so have lower latency.

How to use jquery $.post() method to submit form values

You have to select and send the form data as well:

$("#post-btn").click(function(){        
    $.post("process.php", $("#reg-form").serialize(), function(data) {
        alert(data);
    });
});

Take a look at the documentation for the jQuery serialize method, which encodes the data from the form fields into a data-string to be sent to the server.

How do I decode a string with escaped unicode?

I don't have enough rep to put this under comments to the existing answers:

unescape is only deprecated for working with URIs (or any encoded utf-8) which is probably the case for most people's needs. encodeURIComponent converts a js string to escaped UTF-8 and decodeURIComponent only works on escaped UTF-8 bytes. It throws an error for something like decodeURIComponent('%a9'); // error because extended ascii isn't valid utf-8 (even though that's still a unicode value), whereas unescape('%a9'); // © So you need to know your data when using decodeURIComponent.

decodeURIComponent won't work on "%C2" or any lone byte over 0x7f because in utf-8 that indicates part of a surrogate. However decodeURIComponent("%C2%A9") //gives you © Unescape wouldn't work properly on that // © AND it wouldn't throw an error, so unescape can lead to buggy code if you don't know your data.

How can strings be concatenated?

For cases of appending to end of existing string:

string = "Sec_"
string += "C_type"
print(string)

results in

Sec_C_type

Why does javascript replace only first instance when using replace?

Unlike the C#/.NET class library (and most other sensible languages), when you pass a String in as the string-to-match argument to the string.replace method, it doesn't do a string replace. It converts the string to a RegExp and does a regex substitution. As Gumbo explains, a regex substitution requires the g?lobal flag, which is not on by default, to replace all matches in one go.

If you want a real string-based replace — for example because the match-string is dynamic and might contain characters that have a special meaning in regexen — the JavaScript idiom for that is:

var id= 'c_'+date.split('/').join('');

HTML input field hint

I have the same problem, and I have add this code to my application and its work fine for me.

step -1 : added the jquery.placeholder.js plugin

step -2 :write the below code in your area.

$(function () {
       $('input, textarea').placeholder();
});

And now I can see placeholders on the input boxes!

How to save a data.frame in R?

Let us say you have a data frame you created and named "Data_output", you can simply export it to same directory by using the following syntax.

write.csv(Data_output, "output.csv", row.names = F, quote = F)

credit to Peter and Ilja, UMCG, the Netherlands

How to make Regular expression into non-greedy?

The non-greedy regex modifiers are like their greedy counter-parts but with a ? immediately following them:

*  - zero or more
*? - zero or more (non-greedy)
+  - one or more
+? - one or more (non-greedy)
?  - zero or one
?? - zero or one (non-greedy)

Better naming in Tuple classes than "Item1", "Item2"

I think I would create a class but another alternative is output parameters.

public void GetOrderRelatedIds(out int OrderGroupId, out int OrderTypeId, out int OrderSubTypeId, out int OrderRequirementId)

Since your Tuple only contains integers you could represent it with a Dictionary<string,int>

var orderIds = new Dictionary<string, int> {
    {"OrderGroupId", 1},
    {"OrderTypeId", 2},
    {"OrderSubTypeId", 3},
    {"OrderRequirementId", 4}.
};

but I don't recommend that either.

Calculating the area under a curve given a set of coordinates, without knowing the function

You can use Simpsons rule or the Trapezium rule to calculate the area under a graph given a table of y-values at a regular interval.

Python script that calculates Simpsons rule:

def integrate(y_vals, h):
    i = 1
    total = y_vals[0] + y_vals[-1]
    for y in y_vals[1:-1]:
        if i % 2 == 0:
            total += 2 * y
        else:
            total += 4 * y
        i += 1
    return total * (h / 3.0)

h is the offset (or gap) between y values, and y_vals is an array of well, y values.

Example (In same file as above function):

y_values = [13, 45.3, 12, 1, 476, 0]
interval = 1.2
area = integrate(y_values, interval)
print("The area is", area)

making matplotlib scatter plots from dataframes in Python's pandas

Try passing columns of the DataFrame directly to matplotlib, as in the examples below, instead of extracting them as numpy arrays.

df = pd.DataFrame(np.random.randn(10,2), columns=['col1','col2'])
df['col3'] = np.arange(len(df))**2 * 100 + 100

In [5]: df
Out[5]: 
       col1      col2  col3
0 -1.000075 -0.759910   100
1  0.510382  0.972615   200
2  1.872067 -0.731010   500
3  0.131612  1.075142  1000
4  1.497820  0.237024  1700

Vary scatter point size based on another column

plt.scatter(df.col1, df.col2, s=df.col3)
# OR (with pandas 0.13 and up)
df.plot(kind='scatter', x='col1', y='col2', s=df.col3)

enter image description here

Vary scatter point color based on another column

colors = np.where(df.col3 > 300, 'r', 'k')
plt.scatter(df.col1, df.col2, s=120, c=colors)
# OR (with pandas 0.13 and up)
df.plot(kind='scatter', x='col1', y='col2', s=120, c=colors)

enter image description here

Scatter plot with legend

However, the easiest way I've found to create a scatter plot with legend is to call plt.scatter once for each point type.

cond = df.col3 > 300
subset_a = df[cond].dropna()
subset_b = df[~cond].dropna()
plt.scatter(subset_a.col1, subset_a.col2, s=120, c='b', label='col3 > 300')
plt.scatter(subset_b.col1, subset_b.col2, s=60, c='r', label='col3 <= 300') 
plt.legend()

enter image description here

Update

From what I can tell, matplotlib simply skips points with NA x/y coordinates or NA style settings (e.g., color/size). To find points skipped due to NA, try the isnull method: df[df.col3.isnull()]

To split a list of points into many types, take a look at numpy select, which is a vectorized if-then-else implementation and accepts an optional default value. For example:

df['subset'] = np.select([df.col3 < 150, df.col3 < 400, df.col3 < 600],
                         [0, 1, 2], -1)
for color, label in zip('bgrm', [0, 1, 2, -1]):
    subset = df[df.subset == label]
    plt.scatter(subset.col1, subset.col2, s=120, c=color, label=str(label))
plt.legend()

enter image description here

How to display binary data as image - extjs 4

In front-end JavaScript/HTML, you can load a binary file as an image, you do not have to convert to base64:

<img src="http://engci.nabisco.com/artifactory/repo/folder/my-image">

my-image is a binary image file. This will load just fine.

How do I implement a callback in PHP?

I cringe every time I use create_function() in php.

Parameters are a coma separated string, the whole function body in a string... Argh... I think they could not have made it uglier even if they tried.

Unfortunately, it is the only choice when creating a named function is not worth the trouble.

Handling exceptions from Java ExecutorService tasks

Instead of subclassing ThreadPoolExecutor, I would provide it with a ThreadFactory instance that creates new Threads and provides them with an UncaughtExceptionHandler

How do I get the full url of the page I am on in C#

Here is a list I normally refer to for this type of information:

Request.ApplicationPath :   /virtual_dir
Request.CurrentExecutionFilePath :  /virtual_dir/webapp/page.aspx
Request.FilePath :  /virtual_dir/webapp/page.aspx
Request.Path :  /virtual_dir/webapp/page.aspx
Request.PhysicalApplicationPath :   d:\Inetpub\wwwroot\virtual_dir\
Request.QueryString :   /virtual_dir/webapp/page.aspx?q=qvalue
Request.Url.AbsolutePath :  /virtual_dir/webapp/page.aspx
Request.Url.AbsoluteUri :   http://localhost:2000/virtual_dir/webapp/page.aspx?q=qvalue
Request.Url.Host :  localhost
Request.Url.Authority : localhost:80
Request.Url.LocalPath : /virtual_dir/webapp/page.aspx
Request.Url.PathAndQuery :  /virtual_dir/webapp/page.aspx?q=qvalue
Request.Url.Port :  80
Request.Url.Query : ?q=qvalue
Request.Url.Scheme :    http
Request.Url.Segments :  /
    virtual_dir/
    webapp/
    page.aspx

Hopefully you will find this useful!

Postgresql: password authentication failed for user "postgres"

If I remember correctly the user postgres has no DB password set on Ubuntu by default. That means, that you can login to that account only by using the postgres OS user account.

Assuming, that you have root access on the box you can do:

sudo -u postgres psql

If that fails with a database "postgres" does not exists error, then you are most likely not on a Ubuntu or Debian server :-) In this case simply add template1 to the command:

sudo -u postgres psql template1

If any of those commands fail with an error psql: FATAL: password authentication failed for user "postgres" then check the file /etc/postgresql/8.4/main/pg_hba.conf: There must be a line like this as the first non-comment line:

local   all         postgres                          ident

For newer versions of PostgreSQL ident actually might be peer. That's OK also.

Inside the psql shell you can give the DB user postgres a password:

ALTER USER postgres PASSWORD 'newPassword';

You can leave the psql shell by typing CtrlD or with the command \q.

Now you should be able to give pgAdmin a valid password for the DB superuser and it will be happy too. :-)

Hibernate Error executing DDL via JDBC Statement

Adding this configuration in application.properties file to fixed this issue easily.

spring.jpa.properties.hibernate.globally_quoted_identifiers=true

How do I make a semi transparent background?

DO NOT use a 1x1 semi transparent PNG. Size the PNG up to 10x10, 100x100, etc. Whatever makes sense on your page. (I used a 200x200 PNG and it was only 0.25 kb, so there's no real concern over file size here.)

After visiting this post, I created my web page with 3, 1x1 PNGs with varying transparency.

Dreamweaver CS5 was tanking. I was having flash backs to DOS!!! Apparently any time I tried to scroll, insert text, basically do anything, DW was trying to reload the semi transparent areas 1x1 pixel at a time ... YIKES!

Adobe tech support didn't even know what the problem was, but told me to rebuild the file (it worked on their systems, incidentally). It was only when I loaded the first transparent PNG into the css file that the doc dove deep again.

Then I found a post on another help site about PNGs crashing Dreamweaver. Size your PNG up; there's no downside to doing so.

disabling spring security in spring boot app

Since security.disable option is banned from usage there is still a way to achieve it from pure config without touching any class flies (for me it creates convenience with environments manipulation and possibility to activate it with ENV variable) if you use Boot

spring.autoconfigure.exclude: org.springframework.boot.autoconfigure.security.servlet.SecurityAutoConfiguration

How can I copy a Python string?

You can copy a string in python via string formatting :

>>> a = 'foo'  
>>> b = '%s' % a  
>>> id(a), id(b)  
(140595444686784, 140595444726400)  

Convert Newtonsoft.Json.Linq.JArray to a list of specific object type

Use IList to get the JArray Count and Use Loop to Convert into List

       var array = result["items"].Value<JArray>();

        IList collection = (IList)array;

        var list = new List<string>();

        for (int i = 0; i < collection.Count; j++)
            {
              list.Add(collection[i].ToString());             
            }                         

Remove characters except digits from string using Python?

The op mentions in the comments that he wants to keep the decimal place. This can be done with the re.sub method (as per the second and IMHO best answer) by explicitly listing the characters to keep e.g.

>>> re.sub("[^0123456789\.]","","poo123.4and5fish")
'123.45'

What is the proper declaration of main in C++?

The two valid mains are int main() and int main(int, char*[]). Any thing else may or may not compile. If main doesn't explicitly return a value, 0 is implicitly returned.

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

delete obj[1];

Note that this will not change array indices. Any array members you delete will remain as "slots" that contain undefined.

How to search multiple columns in MySQL?

You can use the AND or OR operators, depending on what you want the search to return.

SELECT title FROM pages WHERE my_col LIKE %$param1% AND another_col LIKE %$param2%;

Both clauses have to match for a record to be returned. Alternatively:

SELECT title FROM pages WHERE my_col LIKE %$param1% OR another_col LIKE %$param2%;

If either clause matches then the record will be returned.

For more about what you can do with MySQL SELECT queries, try the documentation.

Resource from src/main/resources not found after building with maven

Resources from src/main/resources will be put onto the root of the classpath, so you'll need to get the resource as:

new BufferedReader(new InputStreamReader(getClass().getResourceAsStream("/config.txt")));

You can verify by looking at the JAR/WAR file produced by maven as you'll find config.txt in the root of your archive.

How to check if there exists a process with a given pid in Python?

mluebke code is not 100% correct; kill() can also raise EPERM (access denied) in which case that obviously means a process exists. This is supposed to work:

(edited as per Jason R. Coombs comments)

import errno
import os

def pid_exists(pid):
    """Check whether pid exists in the current process table.
    UNIX only.
    """
    if pid < 0:
        return False
    if pid == 0:
        # According to "man 2 kill" PID 0 refers to every process
        # in the process group of the calling process.
        # On certain systems 0 is a valid PID but we have no way
        # to know that in a portable fashion.
        raise ValueError('invalid PID 0')
    try:
        os.kill(pid, 0)
    except OSError as err:
        if err.errno == errno.ESRCH:
            # ESRCH == No such process
            return False
        elif err.errno == errno.EPERM:
            # EPERM clearly means there's a process to deny access to
            return True
        else:
            # According to "man 2 kill" possible error values are
            # (EINVAL, EPERM, ESRCH)
            raise
    else:
        return True

You can't do this on Windows unless you use pywin32, ctypes or a C extension module. If you're OK with depending from an external lib you can use psutil:

>>> import psutil
>>> psutil.pid_exists(2353)
True

Efficiently counting the number of lines of a text file. (200mb+)

There is a faster way I found that does not require looping through the entire file

only on *nix systems, there might be a similar way on windows ...

$file = '/path/to/your.file';

//Get number of lines
$totalLines = intval(exec("wc -l '$file'"));

What is the most efficient way to concatenate N arrays?

If you are in the middle of piping the result through map/filter/sort etc and you want to concat array of arrays, you can use reduce

let sorted_nums = ['1,3', '4,2']
  .map(item => item.split(','))   // [['1', '3'], ['4', '2']]
  .reduce((a, b) => a.concat(b))  // ['1', '3', '4', '2']
  .sort()                         // ['1', '2', '3', '4']

How can I sanitize user input with PHP?

PHP has the new nice filter_input functions now, that for instance liberate you from finding 'the ultimate e-mail regex' now that there is a built-in FILTER_VALIDATE_EMAIL type

My own filter class (uses JavaScript to highlight faulty fields) can be initiated by either an ajax request or normal form post. (see the example below)

/**
 *  Pork.FormValidator
 *  Validates arrays or properties by setting up simple arrays. 
 *  Note that some of the regexes are for dutch input!
 *  Example:
 * 
 *  $validations = array('name' => 'anything','email' => 'email','alias' => 'anything','pwd'=>'anything','gsm' => 'phone','birthdate' => 'date');
 *  $required = array('name', 'email', 'alias', 'pwd');
 *  $sanitize = array('alias');
 *
 *  $validator = new FormValidator($validations, $required, $sanitize);
 *                  
 *  if($validator->validate($_POST))
 *  {
 *      $_POST = $validator->sanitize($_POST);
 *      // now do your saving, $_POST has been sanitized.
 *      die($validator->getScript()."<script type='text/javascript'>alert('saved changes');</script>");
 *  }
 *  else
 *  {
 *      die($validator->getScript());
 *  }   
 *  
 * To validate just one element:
 * $validated = new FormValidator()->validate('blah@bla.', 'email');
 * 
 * To sanitize just one element:
 * $sanitized = new FormValidator()->sanitize('<b>blah</b>', 'string');
 * 
 * @package pork
 * @author SchizoDuckie
 * @copyright SchizoDuckie 2008
 * @version 1.0
 * @access public
 */
class FormValidator
{
    public static $regexes = Array(
            'date' => "^[0-9]{1,2}[-/][0-9]{1,2}[-/][0-9]{4}\$",
            'amount' => "^[-]?[0-9]+\$",
            'number' => "^[-]?[0-9,]+\$",
            'alfanum' => "^[0-9a-zA-Z ,.-_\\s\?\!]+\$",
            'not_empty' => "[a-z0-9A-Z]+",
            'words' => "^[A-Za-z]+[A-Za-z \\s]*\$",
            'phone' => "^[0-9]{10,11}\$",
            'zipcode' => "^[1-9][0-9]{3}[a-zA-Z]{2}\$",
            'plate' => "^([0-9a-zA-Z]{2}[-]){2}[0-9a-zA-Z]{2}\$",
            'price' => "^[0-9.,]*(([.,][-])|([.,][0-9]{2}))?\$",
            '2digitopt' => "^\d+(\,\d{2})?\$",
            '2digitforce' => "^\d+\,\d\d\$",
            'anything' => "^[\d\D]{1,}\$"
    );
    private $validations, $sanatations, $mandatories, $errors, $corrects, $fields;


    public function __construct($validations=array(), $mandatories = array(), $sanatations = array())
    {
        $this->validations = $validations;
        $this->sanitations = $sanitations;
        $this->mandatories = $mandatories;
        $this->errors = array();
        $this->corrects = array();
    }

    /**
     * Validates an array of items (if needed) and returns true or false
     *
     */
    public function validate($items)
    {
        $this->fields = $items;
        $havefailures = false;
        foreach($items as $key=>$val)
        {
            if((strlen($val) == 0 || array_search($key, $this->validations) === false) && array_search($key, $this->mandatories) === false) 
            {
                $this->corrects[] = $key;
                continue;
            }
            $result = self::validateItem($val, $this->validations[$key]);
            if($result === false) {
                $havefailures = true;
                $this->addError($key, $this->validations[$key]);
            }
            else
            {
                $this->corrects[] = $key;
            }
        }

        return(!$havefailures);
    }

    /**
     *
     *  Adds unvalidated class to thos elements that are not validated. Removes them from classes that are.
     */
    public function getScript() {
        if(!empty($this->errors))
        {
            $errors = array();
            foreach($this->errors as $key=>$val) { $errors[] = "'INPUT[name={$key}]'"; }

            $output = '$$('.implode(',', $errors).').addClass("unvalidated");'; 
            $output .= "new FormValidator().showMessage();";
        }
        if(!empty($this->corrects))
        {
            $corrects = array();
            foreach($this->corrects as $key) { $corrects[] = "'INPUT[name={$key}]'"; }
            $output .= '$$('.implode(',', $corrects).').removeClass("unvalidated");';   
        }
        $output = "<script type='text/javascript'>{$output} </script>";
        return($output);
    }


    /**
     *
     * Sanitizes an array of items according to the $this->sanitations
     * sanitations will be standard of type string, but can also be specified.
     * For ease of use, this syntax is accepted:
     * $sanitations = array('fieldname', 'otherfieldname'=>'float');
     */
    public function sanitize($items)
    {
        foreach($items as $key=>$val)
        {
            if(array_search($key, $this->sanitations) === false && !array_key_exists($key, $this->sanitations)) continue;
            $items[$key] = self::sanitizeItem($val, $this->validations[$key]);
        }
        return($items);
    }


    /**
     *
     * Adds an error to the errors array.
     */ 
    private function addError($field, $type='string')
    {
        $this->errors[$field] = $type;
    }

    /**
     *
     * Sanitize a single var according to $type.
     * Allows for static calling to allow simple sanitization
     */
    public static function sanitizeItem($var, $type)
    {
        $flags = NULL;
        switch($type)
        {
            case 'url':
                $filter = FILTER_SANITIZE_URL;
            break;
            case 'int':
                $filter = FILTER_SANITIZE_NUMBER_INT;
            break;
            case 'float':
                $filter = FILTER_SANITIZE_NUMBER_FLOAT;
                $flags = FILTER_FLAG_ALLOW_FRACTION | FILTER_FLAG_ALLOW_THOUSAND;
            break;
            case 'email':
                $var = substr($var, 0, 254);
                $filter = FILTER_SANITIZE_EMAIL;
            break;
            case 'string':
            default:
                $filter = FILTER_SANITIZE_STRING;
                $flags = FILTER_FLAG_NO_ENCODE_QUOTES;
            break;

        }
        $output = filter_var($var, $filter, $flags);        
        return($output);
    }

    /** 
     *
     * Validates a single var according to $type.
     * Allows for static calling to allow simple validation.
     *
     */
    public static function validateItem($var, $type)
    {
        if(array_key_exists($type, self::$regexes))
        {
            $returnval =  filter_var($var, FILTER_VALIDATE_REGEXP, array("options"=> array("regexp"=>'!'.self::$regexes[$type].'!i'))) !== false;
            return($returnval);
        }
        $filter = false;
        switch($type)
        {
            case 'email':
                $var = substr($var, 0, 254);
                $filter = FILTER_VALIDATE_EMAIL;    
            break;
            case 'int':
                $filter = FILTER_VALIDATE_INT;
            break;
            case 'boolean':
                $filter = FILTER_VALIDATE_BOOLEAN;
            break;
            case 'ip':
                $filter = FILTER_VALIDATE_IP;
            break;
            case 'url':
                $filter = FILTER_VALIDATE_URL;
            break;
        }
        return ($filter === false) ? false : filter_var($var, $filter) !== false ? true : false;
    }       



}

Of course, keep in mind that you need to do your sql query escaping too depending on what type of db your are using (mysql_real_escape_string() is useless for an sql server for instance). You probably want to handle this automatically at your appropriate application layer like an ORM. Also, as mentioned above: for outputting to html use the other php dedicated functions like htmlspecialchars ;)

For really allowing HTML input with like stripped classes and/or tags depend on one of the dedicated xss validation packages. DO NOT WRITE YOUR OWN REGEXES TO PARSE HTML!

How can I clear the NuGet package cache using the command line?

If you need to clear the NuGet cache for your build server/agent you can find the cache for NuGet packages here:

%windir%/ServiceProfiles/[account under build service runs]\AppData\Local\NuGet\Cache

Example:

C:\Windows\ServiceProfiles\NetworkService\AppData\Local\NuGet\Cache

How to resolve the "EVP_DecryptFInal_ex: bad decrypt" during file decryption

Errors: "Bad encrypt / decrypt" "gitencrypt_smudge: FAILURE: openssl error decrypting file"

There are various error strings that are thrown from openssl, depending on respective versions, and scenarios. Below is the checklist I use in case of openssl related issues:

  1. Ideally, openssl is able to encrypt/decrypt using same key (+ salt) & enc algo only.
  2. Ensure that openssl versions (used to encrypt/decrypt), are compatible. For eg. the hash used in openssl changed at version 1.1.0 from MD5 to SHA256. This produces a different key from the same password. Fix: add "-md md5" in 1.1.0 to decrypt data from lower versions, and add "-md sha256 in lower versions to decrypt data from 1.1.0

  3. Ensure that there is a single openssl version installed in your machine. In case there are multiple versions installed simultaneously (in my machine, these were installed :- 'LibreSSL 2.6.5' and 'openssl 1.1.1d'), make the sure that only the desired one appears in your PATH variable.

How to clear/delete the contents of a Tkinter Text widget?

from Tkinter import *

app = Tk()

# Text Widget + Font Size
txt = Text(app, font=('Verdana',8))
txt.pack()

# Delete Button
btn = Button(app, text='Delete', command=lambda: txt.delete(1.0,END))
btn.pack()

app.mainloop()

Here's an example of txt.delete(1.0,END) as mentioned.

The use of lambda makes us able to delete the contents without defining an actual function.

How to close Browser Tab After Submitting a Form?

<?php    
    /* ... SQL EXECUTION TO UPDATE DB ... */

    echo "<script>window.close();</script>";
?>

and Remove the window.close() from the form onsubmit event

Private class declaration

To answer your question:

If we can have inner private class then why can't we have outer private class...?

You can, the distinction is that the inner class is at the "class" access level, whereas the "outer" class is at the "package" access level. From the Oracle Tutorials:

If a class has no modifier (the default, also known as package-private), it is visible only within its own package (packages are named groups of related classes — you will learn about them in a later lesson.)

Thus, package-private (declaring no modifier) is the effect you would expect from declaring an "outer" class private, the syntax is just different.

What is a stored procedure?

  • A stored procedure is a precompiled set of one or more SQL statements which perform some specific task.

  • A stored procedure should be executed stand alone using EXEC

  • A stored procedure can return multiple parameters

  • A stored procedure can be used to implement transact

What is the best java image processing library/approach?

For commercial tools, you might want to try Snowbound.

http://www.snowbound.com/

My experience with them is somewhat dated, but I found their Java Imaging API to be a lot easier to use than JAI and a lot faster.

Their customer support and code samples were very good too.

PHPUnit assert that an exception was thrown?

You can use assertException extension to assert more than one exception during one test execution.

Insert method into your TestCase and use:

public function testSomething()
{
    $test = function() {
        // some code that has to throw an exception
    };
    $this->assertException( $test, 'InvalidArgumentException', 100, 'expected message' );
}

I also made a trait for lovers of nice code..

Append a single character to a string or char array in java?

new StringBuilder().append(str.charAt(0))
                   .append(str.charAt(10))
                   .append(str.charAt(20))
                   .append(str.charAt(30))
                   .toString();

This way you can get the new string with whatever characters you want.

What is the difference between required and ng-required?

I would like to make a addon for tiago's answer:

Suppose you're hiding element using ng-show and adding a required attribute on the same:

<div ng-show="false">
    <input required name="something" ng-model="name"/>
</div>

will throw an error something like :

An invalid form control with name='' is not focusable

This is because you just cannot impose required validation on hidden elements. Using ng-required makes it easier to conditionally apply required validation which is just awesome!!

jQuery prevent change for select

_x000D_
_x000D_
$('#my_select').bind('mousedown', function (event) {_x000D_
         event.preventDefault();_x000D_
         event.stopImmediatePropagation();_x000D_
     });
_x000D_
_x000D_
_x000D_

How can I download a specific Maven artifact in one command line?

You could use the maven dependency plugin which has a nice dependency:get goal since version 2.1. No need for a pom, everything happens on the command line.

To make sure to find the dependency:get goal, you need to explicitly tell maven to use the version 2.1, i.e. you need to use the fully qualified name of the plugin, including the version:

mvn org.apache.maven.plugins:maven-dependency-plugin:2.1:get \
    -DrepoUrl=url \
    -Dartifact=groupId:artifactId:version

UPDATE: With older versions of Maven (prior to 2.1), it is possible to run dependency:get normally (without using the fully qualified name and version) by forcing your copy of maven to use a given version of a plugin.

This can be done as follows:

1. Add the following line within the <settings> element of your ~/.m2/settings.xml file:

<usePluginRegistry>true</usePluginRegistry>

2. Add the file ~/.m2/plugin-registry.xml with the following contents:

<?xml version="1.0" encoding="UTF-8"?>
<pluginRegistry xsi:schemaLocation="http://maven.apache.org/PLUGIN_REGISTRY/1.0.0 http://maven.apache.org/xsd/plugin-registry-1.0.0.xsd"
xmlns="http://maven.apache.org/PLUGIN_REGISTRY/1.0.0"
xmlns:xsi="http://www.w3.org/2001/XMLSchema-instance">
  <plugins>
    <plugin>
      <groupId>org.apache.maven.plugins</groupId>
      <artifactId>maven-dependency-plugin</artifactId>
      <useVersion>2.1</useVersion>
      <rejectedVersions/>
    </plugin>
  </plugins>
</pluginRegistry>

But this doesn't seem to work anymore with maven 2.1/2.2. Actually, according to the Introduction to the Plugin Registry, features of the plugin-registry.xml have been redesigned (for portability) and the plugin registry is currently in a semi-dormant state within Maven 2. So I think we have to use the long name for now (when using the plugin without a pom, which is the idea behind dependency:get).

Skipping Incompatible Libraries at compile

That message isn't actually an error - it's just a warning that the file in question isn't of the right architecture (e.g. 32-bit vs 64-bit, wrong CPU architecture). The linker will keep looking for a library of the right type.

Of course, if you're also getting an error along the lines of can't find lPI-Http then you have a problem :-)

It's hard to suggest what the exact remedy will be without knowing the details of your build system and makefiles, but here are a couple of shots in the dark:

  1. Just to check: usually you would add flags to CFLAGS rather than CTAGS - are you sure this is correct? (What you have may be correct - this will depend on your build system!)
  2. Often the flag needs to be passed to the linker too - so you may also need to modify LDFLAGS

If that doesn't help - can you post the full error output, plus the actual command (e.g. gcc foo.c -m32 -Dxxx etc) that was being executed?

Specifing width of a flexbox flex item: width or basis?

The bottom statement is equivalent to:

.half {
   flex-grow: 0;
   flex-shrink: 0;
   flex-basis: 50%;
}

Which, in this case, would be equivalent as the box is not allowed to flex and therefore retains the initial width set by flex-basis.

Flex-basis defines the default size of an element before the remaining space is distributed so if the element were allowed to flex (grow/shrink) it may not be 50% of the width of the page.

I've found that I regularly return to https://css-tricks.com/snippets/css/a-guide-to-flexbox/ for help regarding flexbox :)

How to read if a checkbox is checked in PHP?

Well, the above examples work only when you want to INSERT a value, not useful for UPDATE different values to different columns, so here is my little trick to update:


//EMPTY ALL VALUES TO 0 
$queryMU ='UPDATE '.$db->dbprefix().'settings SET menu_news = 0, menu_gallery = 0, menu_events = 0, menu_contact = 0';
            $stmtMU = $db->prepare($queryMU);
            $stmtMU->execute();
if(!empty($_POST['check_menus'])) {
    foreach($_POST['check_menus'] as $checkU) {
try {
//UPDATE only the values checked
    $queryMU ='UPDATE '.$db->dbprefix().'settings SET '.$checkU.'= 1';
            $stmtMU = $db->prepare($queryMU);
            $stmtMU->execute();  
        } catch(PDOException $e) {
          $msg = 'Error: ' . $e->getMessage();}

        }
}
<input type="checkbox" value="menu_news" name="check_menus[]" />
<input type="checkbox" value="menu_gallery" name="check_menus[]" />

....

The secret is just update all VALUES first (in this case to 0), and since the will only send the checked values, that means everything you get should be set to 1, so everything you get set it to 1.

Example is PHP but applies for everything.

Have fun :)

How to draw circle in html page?

There are a few unicode circles you could use:

_x000D_
_x000D_
* { font-size: 50px; }
_x000D_
&#x25CB;_x000D_
&#x25CC;_x000D_
&#x25CD;_x000D_
&#x25CE;_x000D_
&#x25CF;
_x000D_
_x000D_
_x000D_

More shapes here.

You can overlay text on the circles if you want to:

_x000D_
_x000D_
#container {_x000D_
    position: relative;_x000D_
}_x000D_
#circle {_x000D_
  font-size: 50px;_x000D_
  color: #58f;_x000D_
}_x000D_
#text {_x000D_
    z-index: 1;_x000D_
    position: absolute;_x000D_
    top: 21px;_x000D_
    left: 11px;_x000D_
}
_x000D_
<div id="container">_x000D_
    <div id="circle">&#x25CF;</div>_x000D_
    <div id="text">a</div>_x000D_
</div>
_x000D_
_x000D_
_x000D_

You could also use a custom font (like this one) if you want to have a higher chance of it looking the same on different systems since not all computers/browsers have the same fonts installed.

What's the difference between .bashrc, .bash_profile, and .environment?

The main difference with shell config files is that some are only read by "login" shells (eg. when you login from another host, or login at the text console of a local unix machine). these are the ones called, say, .login or .profile or .zlogin (depending on which shell you're using).

Then you have config files that are read by "interactive" shells (as in, ones connected to a terminal (or pseudo-terminal in the case of, say, a terminal emulator running under a windowing system). these are the ones with names like .bashrc, .tcshrc, .zshrc, etc.

bash complicates this in that .bashrc is only read by a shell that's both interactive and non-login, so you'll find most people end up telling their .bash_profile to also read .bashrc with something like

[[ -r ~/.bashrc ]] && . ~/.bashrc

Other shells behave differently - eg with zsh, .zshrc is always read for an interactive shell, whether it's a login one or not.

The manual page for bash explains the circumstances under which each file is read. Yes, behaviour is generally consistent between machines.

.profile is simply the login script filename originally used by /bin/sh. bash, being generally backwards-compatible with /bin/sh, will read .profile if one exists.

Get restaurants near my location

Is this what you are looking for?

https://maps.googleapis.com/maps/api/place/search/xml?location=49.260691,-123.137784&radius=500&sensor=false&key=*PlacesAPIKey*&types=restaurant

types is optional

Absolute vs relative URLs

In most instances relative URLs are the way to go, they are portable by nature, which means if you wanted to lift your site and put it someone where else it would work instantly, reducing possibly hours of debugging.

There is a pretty decent article on absolute vs relative URLs, check it out.

How do I properly 'printf' an integer and a string in C?

scanf("%s",str) scans only until it finds a whitespace character. With the input "A 1", it will scan only the first character, hence s2 points at the garbage that happened to be in str, since that array wasn't initialised.

calling a function from class in python - different way

class MathsOperations:
    def __init__ (self, x, y):
        self.a = x
        self.b = y
    def testAddition (self):
        return (self.a + self.b)

    def testMultiplication (self):
        return (self.a * self.b)

then

temp = MathsOperations()
print(temp.testAddition())

How to convert array values to lowercase in PHP?

`$Color = array('A' => 'Blue', 'B' => 'Green', 'c' => 'Red');

$strtolower = array_map('strtolower', $Color);

$strtoupper = array_map('strtoupper', $Color);

print_r($strtolower); print_r($strtoupper);`

What is the difference between task and thread?

In addition to above points, it would be good to know that:

  1. A task is by default a background task. You cannot have a foreground task. On the other hand a thread can be background or foreground (Use IsBackground property to change the behavior).
  2. Tasks created in thread pool recycle the threads which helps save resources. So in most cases tasks should be your default choice.
  3. If the operations are quick, it is much better to use a task instead of thread. For long running operations, tasks do not provide much advantages over threads.

SQL : BETWEEN vs <= and >=

They are the same.

One thing to be careful of, is if you are using this against a DATETIME, the match for the end date will be the beginning of the day:

<= 20/10/2009

is not the same as:

<= 20/10/2009 23:59:59

(it would match against <= 20/10/2009 00:00:00.000)

for-in statement

In Typescript 1.5 and later, you can use for..of as opposed to for..in

var numbers = [1, 2, 3];

for (var number of numbers) {
    console.log(number);
}

Sleep function Visual Basic

This one is much easie.

Threading.Thread.Sleep(3000)

Get index of a key/value pair in a C# dictionary based on the value

Consider using System.Collections.Specialized.OrderedDictionary, though it is not generic, or implement your own (example).

OrderedDictionary does not support IndexOf, but it's easy to implement:

public static class OrderedDictionaryExtensions
{
    public static int IndexOf(this OrderedDictionary dictionary, object value)
    {
        for(int i = 0; i < dictionary.Count; ++i)
        {
            if(dictionary[i] == value) return i;
        }
        return -1;
    }
}

How do I set the path to a DLL file in Visual Studio?

I had the same problem and my problem had nothing to do with paths. One of my dll-s was written in c++ and it turnes out that if your visual studio doesn't know how to open a dll file it will say that it did not find it. What i did was locate which dll it did not find, than searched for that dll in my directories and opened it in a separate visual studio window. When trying to navigate through Solution explorer of that project, visual studio said that it cannot show what is inside and that i need some extra extensions, so that it can open those files. Surely enough, after installing the recomended extension (in my case something to do with c++) the

"This application has failed to start because xxx.dll was not found."

error miraculously dissapeared.

What is the difference between java and core java?

I think when you see the phrase "core Java," they are talking about the basics of the language and maybe some knowledge of Java SE. I don't know why they would bother to put the "core" on there.

How to wrap async function calls into a sync function in Node.js or Javascript?

There is a npm sync module also. which is used for synchronize the process of executing the query.

When you want to run parallel queries in synchronous way then node restrict to do that because it never wait for response. and sync module is much perfect for that kind of solution.

Sample code

/*require sync module*/
var Sync = require('sync');
    app.get('/',function(req,res,next){
      story.find().exec(function(err,data){
        var sync_function_data = find_user.sync(null, {name: "sanjeev"});
          res.send({story:data,user:sync_function_data});
        });
    });


    /*****sync function defined here *******/
    function find_user(req_json, callback) {
        process.nextTick(function () {

            users.find(req_json,function (err,data)
            {
                if (!err) {
                    callback(null, data);
                } else {
                    callback(null, err);
                }
            });
        });
    }

reference link: https://www.npmjs.com/package/sync

Codeigniter : calling a method of one controller from other

Controller to be extended

require_once(PHYSICAL_BASE_URL . 'system/application/controllers/abc.php');

        $report= new onlineAssessmentReport();
        echo ($report->detailView());

What process is listening on a certain port on Solaris?

This is sort of an indirect approach, but you could see if a website loads on your web browser of choice from whatever is running on port 80. Or you could telnet to port 80 and see if you get a response that gives you a clue as to what is running on that port and you can go shut it down. Since port 80 is the default port for http traffic chances are there is some sort of http server running there by default, but there's no guarantee.

In Bash, how do I add a string after each line in a file?

I prefer using awk. If there is only one column, use $0, else replace it with the last column.

One way,

awk '{print $0, "string to append after each line"}' file > new_file

or this,

awk '$0=$0"string to append after each line"' file > new_file

Last Run Date on a Stored Procedure in SQL Server

I use this:

use YourDB;

SELECT 
    object_name(object_id), 
    last_execution_time, 
    last_elapsed_time, 
    execution_count
FROM   
     sys.dm_exec_procedure_stats ps 
where 
      lower(object_name(object_id)) like 'Appl-Name%'
order by 1

What causes this error? "Runtime error 380: Invalid property value"

Just to throw my two cents in: another common cause of this error in my experience is code in the Form_Resize event that uses math to resize controls on a form. Control dimensions (Height and Width) can't be set to negative values, so code like the following in your Form_Resize event can cause this error:

Private Sub Form_Resize()
    'Resize text box to fit the form, with a margin of 1000 twips on the right.'
    'This will error out if the width of the Form drops below 1000 twips.'
    txtFirstName.Width = Me.Width - 1000
End Sub

The above code will raise an an "Invalid property value" error if the form is resized to less than 1000 twips wide. If this is the problem, the easiest solution is to add On Error Resume Next as the first line, so that these kinds of errors are ignored. This is one of those rare situations in VB6 where On Error Resume Next is your friend.

Python: subplot within a loop: first panel appears in wrong position

Using your code with some random data, this would work:

fig, axs = plt.subplots(2,5, figsize=(15, 6), facecolor='w', edgecolor='k')
fig.subplots_adjust(hspace = .5, wspace=.001)

axs = axs.ravel()

for i in range(10):

    axs[i].contourf(np.random.rand(10,10),5,cmap=plt.cm.Oranges)
    axs[i].set_title(str(250+i))

The layout is off course a bit messy, but that's because of your current settings (the figsize, wspace etc).

enter image description here

File 'app/hero.ts' is not a module error in the console, where to store interfaces files in directory structure with angular2?

probably you forgot to add "Export" in the class definition.

-->

export class Hero {
     id: number;
     name: string;
   }

Also, try with

export {Hero} 

at the bottom of your hero.ts class, and finally, check capital letter file name and class name.

How to change port for jenkins window service when 8080 is being used

1 ) Open the jenkins.xml file
2 ) Search for the "--httpPort=8080" Text and replace the port number 8080 with your custom port number (like 7070 , 9090 )
3 ) Go to your services running your machine & find out the Jenkins service and click on restart.

enter image description here

Opacity CSS not working in IE8

None of the answers above worked for me, so I just gave my DIV tag a transparent background image instead, that worked perfectly for all browsers.

How to place a JButton at a desired location in a JFrame using Java

Following line should be called before you add your component

pnlButton.setLayout(null);

Above will set your content panel to use absolute layout. This means you'd always have to set your component's bounds explicitly by using setBounds method.

In general I wouldn't recommend using absolute layout.

Change tab bar tint color on iOS 7

You can set your tint color and font as setTitleTextattribute:

UIFont *font= (kUIScreenHeight>KipadHeight)?[UIFont boldSystemFontOfSize:32.0f]:[UIFont boldSystemFontOfSize:16.0f];
NSDictionary *attributes = [NSDictionary dictionaryWithObjectsAndKeys:font, NSFontAttributeName,
                            tintColorLight, NSForegroundColorAttributeName, nil];
[[UINavigationBar appearance] setTitleTextAttributes:attributes];

Compiling a C++ program with gcc

The difference between gcc and g++ are:

     gcc            |        g++
compiles c source   |   compiles c++ source

use g++ instead of gcc to compile you c++ source.

Making an API call in Python with an API that requires a bearer token

It just means it expects that as a key in your header data

import requests
endpoint = ".../api/ip"
data = {"ip": "1.1.2.3"}
headers = {"Authorization": "Bearer MYREALLYLONGTOKENIGOT"}

print(requests.post(endpoint, data=data, headers=headers).json())

Can't type in React input text field

Once I ran into a similar error. Let me describe it.

Edit.js

   // components returns edit form 
   
   function EditVideo({id}) {
   .....
   
   // onChange event listener 
    const handleChange = (e) => {
       setTextData({
           ...textData,
           [e.target.name]: e.target.value.trim()
        });
     }
  
   ....
   ...
   }
)

ImportEdit.js

   import Edit from './Edit';
   
    function ImportEdit() {
    ......
     ...
    return (
        <div>
            <EditVideo id={id}/>
        </div>
       )
    }

    export default ImportEdit

The Problem was: I was unable to use spacebar (i.e. if i press spacekey, i didn't see space input)

The Bug: .trim()

.trim() method was trimming all the white space i typed

Note: Edit.js worked fine when used sepeartely without import

starting file download with JavaScript

A agree with the methods mentioned by maxnk, however you may want to reconsider trying to automatically force the browser to download the URL. It may work fine for binary files but for other types of files (text, PDF, images, video), the browser may want to render it in the window (or IFRAME) rather than saving to disk.

If you really do need to make an Ajax call to get the final download links, what about using DHTML to dynamically write out the download link (from the ajax response) into the page? That way the user could either click on it to download (if binary) or view in their browser - or select "Save As" on the link to save to disk. It's an extra click, but the user has more control.

Plot width settings in ipython notebook

If you use %pylab inline you can (on a new line) insert the following command:

%pylab inline
pylab.rcParams['figure.figsize'] = (10, 6)

This will set all figures in your document (unless otherwise specified) to be of the size (10, 6), where the first entry is the width and the second is the height.

See this SO post for more details. https://stackoverflow.com/a/17231361/1419668

Check if XML Element exists

Not sure what you're wanting to do but using a DTD or schema might be all you need to validate the xml.

Otherwise, if you want to find an element you could use an xpath query to search for a particular element.

How do I output text without a newline in PowerShell?

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

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

or the equivalent by multiple calls to Write-Output,

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

concatenate your components into a STRING VARIABLE first:

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

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

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

Set colspan dynamically with jquery

td.setAttribute('rowspan',x);

Why do I get "MismatchSenderId" from GCM server side?

Please run below script in your terminal

curl -X POST \
-H "Authorization: key=  write here api_key" \
-H "Content-Type: application/json" \
-d '{ 
"registration_ids": [ 
"write here reg_id generated by gcm"
], 
"data": { 
"message": "Manual push notification from Rajkumar"
},
"priority": "high"
}' \
https://android.googleapis.com/gcm/send

it will give the message if it is succeeded or failed

Send JSON data from Javascript to PHP?

This is a summary of the main solutions with easy-to-reproduce code:

Method 1 (application/json or text/plain + JSON.stringify)

var data = {foo: 'blah "!"', bar: 123};
var xhr = new XMLHttpRequest();
xhr.open("POST", "test.php");
xhr.onreadystatechange = function() { if (xhr.readyState === 4 && xhr.status === 200) { console.log(xhr.responseText); } }
xhr.setRequestHeader("Content-type", "application/json") // or "text/plain"
xhr.send(JSON.stringify(data)); 

PHP side, you can get the data with:

print_r(json_decode(file_get_contents('php://input'), true));

Method 2 (x-www-form-urlencoded + JSON.stringify)

var data = {foo: 'blah "!"', bar: 123};
var xhr = new XMLHttpRequest();
xhr.open("POST", "test.php");
xhr.onreadystatechange = function() { if (xhr.readyState === 4 && xhr.status === 200) { console.log(xhr.responseText); } }
xhr.setRequestHeader("Content-type", "application/x-www-form-urlencoded");
xhr.send("json=" + encodeURIComponent(JSON.stringify(data))); 

Note: encodeURIComponent(...) is needed for example if the JSON contains & character.

PHP side, you can get the data with:

print_r(json_decode($_POST['json'], true));

Method 3 (x-www-form-urlencoded + URLSearchParams)

var data = {foo: 'blah "!"', bar: 123};
var xhr = new XMLHttpRequest();
xhr.open("POST", "test.php");
xhr.onreadystatechange = function() { if (xhr.readyState === 4 && xhr.status === 200) { console.log(xhr.responseText); } }
xhr.setRequestHeader("Content-type", "application/x-www-form-urlencoded");
xhr.send(new URLSearchParams(data).toString()); 

PHP side, you can get the data with:

print_r($_POST);

Note: https://caniuse.com/#search=URLSearchParams

To show only file name without the entire directory path

No need for Xargs and all , ls is more than enough.

ls -1 *.txt

displays row wise

How to split a string after specific character in SQL Server and update this value to specific column

I know this question is specific to sql server, but I'm using postgresql and came across this question, so for anybody else in a similar situation, there is the split_part(string text, delimiter text, field int) function.

Passing parameter using onclick or a click binding with KnockoutJS

If you set up a click binding in Knockout the event is passed as the second parameter. You can use the event to obtain the element that the click occurred on and perform whatever action you want.

Here is a fiddle that demonstrates: http://jsfiddle.net/jearles/xSKyR/

Alternatively, you could create your own custom binding, which will receive the element it is bound to as the first parameter. On init you could attach your own click event handler to do any actions you wish.

http://knockoutjs.com/documentation/custom-bindings.html

HTML

<div>
    <button data-bind="click: clickMe">Click Me!</button>
</div>

Js

var ViewModel = function() {
    var self = this;
    self.clickMe = function(data,event) {

      var target = event.target || event.srcElement;

      if (target.nodeType == 3) // defeat Safari bug
        target = target.parentNode;

      target.parentNode.innerHTML = "something";
    }
}

ko.applyBindings(new ViewModel());

Get column from a two dimensional array

_x000D_
_x000D_
function arrayColumn(arr, n) {_x000D_
  return arr.map(x=> x[n]);_x000D_
}_x000D_
_x000D_
var twoDimensionalArray = [_x000D_
  [1, 2, 3],_x000D_
  [4, 5, 6],_x000D_
  [7, 8, 9]_x000D_
];_x000D_
_x000D_
console.log(arrayColumn(twoDimensionalArray, 1));
_x000D_
_x000D_
_x000D_

What do curly braces mean in Verilog?

The curly braces mean concatenation, from most significant bit (MSB) on the left down to the least significant bit (LSB) on the right. You are creating a 32-bit bus (result) whose 16 most significant bits consist of 16 copies of bit 15 (the MSB) of the a bus, and whose 16 least significant bits consist of just the a bus (this particular construction is known as sign extension, which is needed e.g. to right-shift a negative number in two's complement form and keep it negative rather than introduce zeros into the MSBits).

There is a tutorial here*, but it doesn't explain too much more than the above paragraph.

For what it's worth, the nested curly braces around a[15:0] are superfluous.

*Beware: the example within the tutorial link contains a typo when demonstrating multiple concatenations - the (2{C}} should be a {2{2}}.

What is Express.js?

1) What is Express.js?

Express.js is a Node.js framework. It's the most popular framework as of now (the most starred on NPM).

Enter image description here.

It's built around configuration and granular simplicity of Connect middleware. Some people compare Express.js to Ruby Sinatra vs. the bulky and opinionated Ruby on Rails.

2) What is the purpose of it with Node.js?

That you don't have to repeat same code over and over again. Node.js is a low-level I/O mechanism which has an HTTP module. If you just use an HTTP module, a lot of work like parsing the payload, cookies, storing sessions (in memory or in Redis), selecting the right route pattern based on regular expressions will have to be re-implemented. With Express.js, it is just there for you to use.

3) Why do we actually need Express.js? How it is useful for us to use with Node.js?

The first answer should answer your question. If no, then try to write a small REST API server in plain Node.js (that is, using only core modules) and then in Express.js. The latter will take you 5-10x less time and lines of code.

What is Redis? Does it come with Express.js?

Redis is a fast persistent key-value storage. You can optionally use it for storing sessions with Express.js, but you don't need to. By default, Express.js has memory storage for sessions. Redis also can be use for queueing jobs, for example, email jobs.

Check out my tutorial on REST API server with Express.js.

MVC but not by itself

Express.js is not an model-view-controller framework by itself. You need to bring your own object-relational mapping libraries such as Mongoose for MongoDB, Sequelize (http://sequelizejs.com) for SQL databases, Waterline (https://github.com/balderdashy/waterline) for many databases into the stack.

Alternatives

Other Node.js frameworks to consider (https://www.quora.com/Node-js/Which-Node-js-framework-is-best-for-building-a-RESTful-API):

UPDATE: I put together this resource that aid people in choosing Node.js frameworks: http://nodeframework.com

UPDATE2: We added some GitHub stats to nodeframework.com so now you can compare the level of social proof (GitHub stars) for 30+ frameworks on one page.

enter image description here

Full-stack:

Just REST API:

Ruby on Rails like:

Sinatra like:

Other:

Middleware:

Static site generators:

Currency formatting in Python

This is an ancient post, but I just implemented the following solution which:

  • Doesn't require external modules
  • Doesn't require creating a new function
  • Can be done in-line
  • Handles multiple variables
  • Handles negative dollar amounts

Code:

num1 = 4153.53
num2 = -23159.398598

print 'This: ${:0,.0f} and this: ${:0,.2f}'.format(num1, num2).replace('$-','-$')

Output:

This: $4,154 and this: -$23,159.40

And for the original poster, obviously, just switch $ for £

Angular2 module has no exported member

Also some of common cases :

maybe you export class with "default" prefix like so

export default class Module {}

just remove it

export class Module {}

this is solve the issue for me

How to disable Google asking permission to regularly check installed apps on my phone?

In Nexus 5, Go to Settings -> Google -> Security and uncheck "Scan device for Security threats" and "Improve harmful app detection".

Viewing localhost website from mobile device

You can solve the problem by downloading the 'conveyor' library from extensions and update in Visual Studio.

You can access it from other devices.

  • Open Visual Studio

  • Tools > Extensions and Updates

  • Online > Visual Studio Marketplace

  • Search 'Conveyor'
  • Download and install this extension

When you launch the API, you can access it from other devices. This plugin creates a link from your own ip address.

Example: https://youripadress:5000/api/values

How to write a multiline Jinja statement

According to the documentation: https://jinja.palletsprojects.com/en/2.10.x/templates/#line-statements you may use multi-line statements as long as the code has parens/brackets around it. Example:

{% if ( (foo == 'foo' or bar == 'bar') and 
        (fooo == 'fooo' or baar == 'baar') ) %}
    <li>some text</li>
{% endif %}

Edit: Using line_statement_prefix = '#'* the code would look like this:

# if ( (foo == 'foo' or bar == 'bar') and 
       (fooo == 'fooo' or baar == 'baar') )
    <li>some text</li>
# endif

*Here's an example of how you'd specify the line_statement_prefix in the Environment:

from jinja2 import Environment, PackageLoader, select_autoescape
env = Environment(
    loader=PackageLoader('yourapplication', 'templates'),
    autoescape=select_autoescape(['html', 'xml']),
    line_statement_prefix='#'
)

Or using Flask:

from flask import Flask
app = Flask(__name__, instance_relative_config=True, static_folder='static')
app.jinja_env.filters['zip'] = zip
app.jinja_env.line_statement_prefix = '#'

How to set the first option on a select box using jQuery?

If you just want to reset the select element to it's first position, the simplest way may be:

$('#name2').val('');

To reset all select elements in the document:

$('select').val('')

EDIT: To clarify as per a comment below, this resets the select element to its first blank entry and only if a blank entry exists in the list.

SQL Server - INNER JOIN WITH DISTINCT

Try this:

select distinct a.FirstName, a.LastName, v.District
from AddTbl a 
  inner join ValTbl v
  on a.LastName = v.LastName
order by a.FirstName;

Or this (it does the same, but the syntax is different):

select distinct a.FirstName, a.LastName, v.District
from AddTbl a, ValTbl v
where a.LastName = v.LastName
order by a.FirstName;

How can I compare two time strings in the format HH:MM:SS?

You can easily do it with below code:

Note: The second argument in RegExp is 'g' which is the global search flag. The global search flag makes the RegExp search for a pattern throughout the string, creating an array of all occurrences it can find matching the given pattern. Below code only works if the time is in HH:MM:SS format i.e. 24 hour time format.

var regex = new RegExp(':', 'g'),
    timeStr1 = '5:50:55',
    timeStr2 = '6:17:05';
if(parseInt(timeStr1.replace(regex, ''), 10) < parseInt(timeStr2.replace(regex, ''), 10)){
  console.log('timeStr1 is smaller then timeStr2');
} else {
  console.log('timeStr2 is smaller then timeStr1');
}

jQuery - find child with a specific class

$(this).find(".bgHeaderH2").html();

or

$(this).find(".bgHeaderH2").text();

Using arrays or std::vectors in C++, what's the performance gap?

There is definitely a performance impact to using an std::vector vs a raw array when you want an uninitialized buffer (e.g. to use as destination for memcpy()). An std::vector will initialize all its elements using the default constructor. A raw array will not.

The c++ spec for the std:vector constructor taking a count argument (it's the third form) states:

`Constructs a new container from a variety of data sources, optionally using a user supplied allocator alloc.

  1. Constructs the container with count default-inserted instances of T. No copies are made.

Complexity

2-3) Linear in count

A raw array does not incur this initialization cost.

Note that with a custom allocator, it is possible to avoid "initialization" of the vector's elements (i.e. to use default initialization instead of value initialization). See these questions for more details:

Testing if a checkbox is checked with jQuery

I've found the same problem before, hope this solution can help you. first, add a custom attribute to your checkboxes:

<input type="checkbox" id="ans" value="1" data-unchecked="0" />

write a jQuery extension to get value:

$.fn.realVal = function(){
    var $obj = $(this);
    var val = $obj.val();
    var type = $obj.attr('type');
    if (type && type==='checkbox') {
        var un_val = $obj.attr('data-unchecked');
        if (typeof un_val==='undefined') un_val = '';
        return $obj.prop('checked') ? val : un_val;
    } else {
        return val;
    }
};

use code to get check-box value:

$('#ans').realVal();

you can test here

How to crop an image using PIL?

There is a crop() method:

w, h = yourImage.size
yourImage.crop((0, 30, w, h-30)).save(...)

Invoke JSF managed bean action on page load

@PostConstruct is run ONCE in first when Bean Created. the solution is create a Unused property and Do your Action in Getter method of this property and add this property to your .xhtml file like this :

<h:inputHidden  value="#{loginBean.loginStatus}"/>

and in your bean code:

public void setLoginStatus(String loginStatus) {
    this.loginStatus = loginStatus;
}

public String getLoginStatus()  {
    // Do your stuff here.
    return loginStatus;
}

How do I install command line MySQL client on mac?

There is now a mysql-client formula.

brew install mysql-client

What is the origin of foo and bar?

tl;dr

  • "Foo" and "bar" as metasyntactic variables were popularised by MIT and DEC, the first references are in work on LISP and PDP-1 and Project MAC from 1964 onwards.

  • Many of these people were in MIT's Tech Model Railroad Club, where we find the first documented use of "foo" in tech circles in 1959 (and a variant in 1958).

  • Both "foo" and "bar" (and even "baz") were well known in popular culture, especially from Smokey Stover and Pogo comics, which will have been read by many TMRC members.

  • Also, it seems likely the military FUBAR contributed to their popularity.


The use of lone "foo" as a nonsense word is pretty well documented in popular culture in the early 20th century, as is the military FUBAR. (Some background reading: FOLDOC FOLDOC Jargon File Jargon File Wikipedia RFC3092)


OK, so let's find some references.

STOP PRESS! After posting this answer, I discovered this perfect article about "foo" in the Friday 14th January 1938 edition of The Tech ("MIT's oldest and largest newspaper & the first newspaper published on the web"), Volume LVII. No. 57, Price Three Cents:

On Foo-ism

The Lounger thinks that this business of Foo-ism has been carried too far by its misguided proponents, and does hereby and forthwith take his stand against its abuse. It may be that there's no foo like an old foo, and we're it, but anyway, a foo and his money are some party. (Voice from the bleachers- "Don't be foo-lish!")

As an expletive, of course, "foo!" has a definite and probably irreplaceable position in our language, although we fear that the excessive use to which it is currently subjected may well result in its falling into an early (and, alas, a dark) oblivion. We say alas because proper use of the word may result in such happy incidents as the following.

It was an 8.50 Thermodynamics lecture by Professor Slater in Room 6-120. The professor, having covered the front side of the blackboard, set the handle that operates the lift mechanism, turning meanwhile to the class to continue his discussion. The front board slowly, majestically, lifted itself, revealing the board behind it, and on that board, writ large, the symbols that spelled "FOO"!

The Tech newspaper, a year earlier, the Letter to the Editor, September 1937:

By the time the train has reached the station the neophytes are so filled with the stories of the glory of Phi Omicron Omicron, usually referred to as Foo, that they are easy prey.

...

It is not that I mind having lost my first four sons to the Grand and Universal Brotherhood of Phi Omicron Omicron, but I do wish that my fifth son, my baby, should at least be warned in advance.

Hopefully yours,

Indignant Mother of Five.

And The Tech in December 1938:

General trend of thought might be best interpreted from the remarks made at the end of the ballots. One vote said, '"I don't think what I do is any of Pulver's business," while another merely added a curt "Foo."


The first documented "foo" in tech circles is probably 1959's Dictionary of the TMRC Language:

FOO: the sacred syllable (FOO MANI PADME HUM); to be spoken only when under inspiration to commune with the Deity. Our first obligation is to keep the Foo Counters turning.

These are explained at FOLDOC. The dictionary's compiler Pete Samson said in 2005:

Use of this word at TMRC antedates my coming there. A foo counter could simply have randomly flashing lights, or could be a real counter with an obscure input.

And from 1996's Jargon File 4.0.0:

Earlier versions of this lexicon derived 'baz' as a Stanford corruption of bar. However, Pete Samson (compiler of the TMRC lexicon) reports it was already current when he joined TMRC in 1958. He says "It came from "Pogo". Albert the Alligator, when vexed or outraged, would shout 'Bazz Fazz!' or 'Rowrbazzle!' The club layout was said to model the (mythical) New England counties of Rowrfolk and Bassex (Rowrbazzle mingled with (Norfolk/Suffolk/Middlesex/Essex)."

A year before the TMRC dictionary, 1958's MIT Voo Doo Gazette ("Humor suplement of the MIT Deans' office") (PDF) mentions Foocom, in "The Laws of Murphy and Finagle" by John Banzhaf (an electrical engineering student):

Further research under a joint Foocom and Anarcom grant expanded the law to be all embracing and universally applicable: If anything can go wrong, it will!

Also 1964's MIT Voo Doo (PDF) references the TMRC usage:

Yes! I want to be an instant success and snow customers. Send me a degree in: ...

  • Foo Counters

  • Foo Jung


Let's find "foo", "bar" and "foobar" published in code examples.

So, Jargon File 4.4.7 says of "foobar":

Probably originally propagated through DECsystem manuals by Digital Equipment Corporation (DEC) in 1960s and early 1970s; confirmed sightings there go back to 1972.

The first published reference I can find is from February 1964, but written in June 1963, The Programming Language LISP: its Operation and Applications by Information International, Inc., with many authors, but including Timothy P. Hart and Michael Levin:

Thus, since "FOO" is a name for itself, "COMITRIN" will treat both "FOO" and "(FOO)" in exactly the same way.

Also includes other metasyntactic variables such as: FOO CROCK GLITCH / POOT TOOR / ON YOU / SNAP CRACKLE POP / X Y Z

I expect this is much the same as this next reference of "foo" from MIT's Project MAC in January 1964's AIM-064, or LISP Exercises by Timothy P. Hart and Michael Levin:

car[((FOO . CROCK) . GLITCH)]

It shares many other metasyntactic variables like: CHI / BOSTON NEW YORK / SPINACH BUTTER STEAK / FOO CROCK GLITCH / POOT TOOP / TOOT TOOT / ISTHISATRIVIALEXCERCISE / PLOOP FLOT TOP / SNAP CRACKLE POP / ONE TWO THREE / PLANE SUB THRESHER

For both "foo" and "bar" together, the earliest reference I could find is from MIT's Project MAC in June 1966's AIM-098, or PDP-6 LISP by none other than Peter Samson:

EXPLODE, like PRIN1, inserts slashes, so (EXPLODE (QUOTE FOO/ BAR)) PRIN1's as (F O O // / B A R) or PRINC's as (F O O / B A R).


Some more recallations.

@Walter Mitty recalled on this site in 2008:

I second the jargon file regarding Foo Bar. I can trace it back at least to 1963, and PDP-1 serial number 2, which was on the second floor of Building 26 at MIT. Foo and Foo Bar were used there, and after 1964 at the PDP-6 room at project MAC.

John V. Everett recalls in 1996:

When I joined DEC in 1966, foobar was already being commonly used as a throw-away file name. I believe fubar became foobar because the PDP-6 supported six character names, although I always assumed the term migrated to DEC from MIT. There were many MIT types at DEC in those days, some of whom had worked with the 7090/7094 CTSS. Since the 709x was also a 36 bit machine, foobar may have been used as a common file name there.

Foo and bar were also commonly used as file extensions. Since the text editors of the day operated on an input file and produced an output file, it was common to edit from a .foo file to a .bar file, and back again.

It was also common to use foo to fill a buffer when editing with TECO. The text string to exactly fill one disk block was IFOO$HXA127GA$$. Almost all of the PDP-6/10 programmers I worked with used this same command string.

Daniel P. B. Smith in 1998:

Dick Gruen had a device in his dorm room, the usual assemblage of B-battery, resistors, capacitors, and NE-2 neon tubes, which he called a "foo counter." This would have been circa 1964 or so.

Robert Schuldenfrei in 1996:

The use of FOO and BAR as example variable names goes back at least to 1964 and the IBM 7070. This too may be older, but that is where I first saw it. This was in Assembler. What would be the FORTRAN integer equivalent? IFOO and IBAR?

Paul M. Wexelblat in 1992:

The earliest PDP-1 Assembler used two characters for symbols (18 bit machine) programmers always left a few words as patch space to fix problems. (Jump to patch space, do new code, jump back) That space conventionally was named FU: which stood for Fxxx Up, the place where you fixed Fxxx Ups. When spoken, it was known as FU space. Later Assemblers ( e.g. MIDAS allowed three char tags so FU became FOO, and as ALL PDP-1 programmers will tell you that was FOO space.

Bruce B. Reynolds in 1996:

On the IBM side of FOO(FU)BAR is the use of the BAR side as Base Address Register; in the middle 1970's CICS programmers had to worry out the various xxxBARs...I think one of those was FRACTBAR...

Here's a straight IBM "BAR" from 1955.


Other early references:


I haven't been able to find any references to foo bar as "inverted foo signal" as suggested in RFC3092 and elsewhere.

Here are a some of even earlier F00s but I think they're coincidences/false positives:

Relative frequencies / proportions with dplyr

Try this:

mtcars %>%
  group_by(am, gear) %>%
  summarise(n = n()) %>%
  mutate(freq = n / sum(n))

#   am gear  n      freq
# 1  0    3 15 0.7894737
# 2  0    4  4 0.2105263
# 3  1    4  8 0.6153846
# 4  1    5  5 0.3846154

From the dplyr vignette:

When you group by multiple variables, each summary peels off one level of the grouping. That makes it easy to progressively roll-up a dataset.

Thus, after the summarise, the last grouping variable specified in group_by, 'gear', is peeled off. In the mutate step, the data is grouped by the remaining grouping variable(s), here 'am'. You may check grouping in each step with groups.

The outcome of the peeling is of course dependent of the order of the grouping variables in the group_by call. You may wish to do a subsequent group_by(am), to make your code more explicit.

For rounding and prettification, please refer to the nice answer by @Tyler Rinker.

How to use matplotlib tight layout with Figure?

Just call fig.tight_layout() as you normally would. (pyplot is just a convenience wrapper. In most cases, you only use it to quickly generate figure and axes objects and then call their methods directly.)

There shouldn't be a difference between the QtAgg backend and the default backend (or if there is, it's a bug).

E.g.

import matplotlib.pyplot as plt

#-- In your case, you'd do something more like:
# from matplotlib.figure import Figure
# fig = Figure()
#-- ...but we want to use it interactive for a quick example, so 
#--    we'll do it this way
fig, axes = plt.subplots(nrows=4, ncols=4)

for i, ax in enumerate(axes.flat, start=1):
    ax.set_title('Test Axes {}'.format(i))
    ax.set_xlabel('X axis')
    ax.set_ylabel('Y axis')

plt.show()

Before Tight Layout

enter image description here

After Tight Layout

import matplotlib.pyplot as plt

fig, axes = plt.subplots(nrows=4, ncols=4)

for i, ax in enumerate(axes.flat, start=1):
    ax.set_title('Test Axes {}'.format(i))
    ax.set_xlabel('X axis')
    ax.set_ylabel('Y axis')

fig.tight_layout()

plt.show()

enter image description here

How to create a HTML Cancel button that redirects to a URL

There are a few problems here.

First of all, there is no such thing as <button type="cancel">, so it is treated as just a <button>. This means that your form will be submitted, instead of the button taking you elsewhere.

Second, javascript: is only needed in href or action attributes, where a URL is expected, to designate JavaScript code. Inside onclick, where JavaScript is already expected, it merely acts as a label and serves no real purpose.

Finally, it's just generally better design to have a cancel link rather than a cancel button. So you can just do this:

<a href="http://stackoverflow.com/">Cancel</a>

With CSS you can even make it look the same as a button, but with this HTML there is absolutely no confusion as to what it is supposed to do.

Delete all the records

If you want to reset your table, you can do

truncate table TableName

truncate needs privileges, and you can't use it if your table has dependents (another tables that have FK of your table,

why numpy.ndarray is object is not callable in my simple for python loop

Avoid loops. What you want to do is:

import numpy as np
data=np.loadtxt(fname="data.txt")## to load the above two column
print data
print data.sum(axis=1)

How to list all the files in a commit?

I use changed alias a quite often. To set it up:

git config --global alias.changed 'show --pretty="format:" --name-only'

then:

git changed (lists files modified in last commit)   
git changed bAda55 (lists files modified in this commit)
git changed bAda55..ff0021 (lists files modified between those commits)

Similar commands that may be useful:

git log --name-status --oneline (very similar, but shows what actually happened M/C/D)
git show --name-only

How can I get the browser's scrollbar sizes?

Already coded in my library so here it is:

var vScrollWidth = window.screen.width - window.document.documentElement.clientWidth;

I should mention that jQuery $(window).width() can also be used instead of window.document.documentElement.clientWidth.

It doesn't work if you open developer tools in firefox on the right but it overcomes it if the devs window is opened at bottom!

window.screen is supported quirksmode.org!

Have fun!

How to check if a string contains a specific text

Empty strings are falsey, so you can just write:

if ($a) {
    echo 'text';
}

Although if you're asking if a particular substring exists in that string, you can use strpos() to do that:

if (strpos($a, 'some text') !== false) {
    echo 'text';
}

Convert all strings in a list to int

You can do it simply in one line when taking input.

[int(i) for i in input().split("")]

Split it where you want.

If you want to convert a list not list simply put your list name in the place of input().split("").

Resize image proportionally with CSS?

Use this easy scaling technique

img {
    max-width: 100%;
    height: auto;
}
@media {
  img { 
    width: auto; /* for ie 8 */
  }
}

Autocompletion of @author in Intellij

For Intellij IDEA Community 2019.1 you will need to follow these steps :

File -> New -> Edit File Templates.. -> Class -> /* Created by ${USER} on ${DATE} */

How can I Remove .DS_Store files from a Git repository?

Open terminal and type "cd < ProjectPath >"

  1. Remove existing files: find . -name .DS_Store -print0 | xargs -0 git rm -f --ignore-unmatch

  2. nano .gitignore

  3. Add this .DS_Store

  4. type "ctrl + x"

  5. Type "y"

  6. Enter to save file

  7. git add .gitignore

  8. git commit -m '.DS_Store removed.'

Composer could not find a composer.json

You are in wrong directory. cd to your project directory then run composer update.

Deleting DataFrame row in Pandas based on column value

If I'm understanding correctly, it should be as simple as:

df = df[df.line_race != 0]

SQL Server Script to create a new user

Based on your question, I think that you may be a bit confused about the difference between a User and a Login. A Login is an account on the SQL Server as a whole - someone who is able to log in to the server and who has a password. A User is a Login with access to a specific database.

Creating a Login is easy and must (obviously) be done before creating a User account for the login in a specific database:

CREATE LOGIN NewAdminName WITH PASSWORD = 'ABCD'
GO

Here is how you create a User with db_owner privileges using the Login you just declared:

Use YourDatabase;
GO

IF NOT EXISTS (SELECT * FROM sys.database_principals WHERE name = N'NewAdminName')
BEGIN
    CREATE USER [NewAdminName] FOR LOGIN [NewAdminName]
    EXEC sp_addrolemember N'db_owner', N'NewAdminName'
END;
GO

Now, Logins are a bit more fluid than I make it seem above. For example, a Login account is automatically created (in most SQL Server installations) for the Windows Administrator account when the database is installed. In most situations, I just use that when I am administering a database (it has all privileges).

However, if you are going to be accessing the SQL Server from an application, then you will want to set the server up for "Mixed Mode" (both Windows and SQL logins) and create a Login as shown above. You'll then "GRANT" priviliges to that SQL Login based on what is needed for your app. See here for more information.

UPDATE: Aaron points out the use of the sp_addsrvrolemember to assign a prepared role to your login account. This is a good idea - faster and easier than manually granting privileges. If you google it you'll see plenty of links. However, you must still understand the distinction between a login and a user.

Display number always with 2 decimal places in <input>

best way to Round off number to decimal places is that

a=parseFloat(Math.round(numbertobeRound*10^decimalplaces)/10^decimalplaces);

for Example ;

numbertobeRound=58.8965896589;

if you want 58.90

decimalplaces is 2

a=parseFloat(Math.round(58.8965896589*10^2)/10^2);

Eclipse will not open due to environment variables

Here is the answer, sorry .. but your solutions weren't correct

set PATH=C:\Program Files\Java\jre1.6.0_03\bin ;%PATH%

paxdiablo Did you rewrite the error or you got some kind of software reading text from image, if you got which one ?

How to install pkg config in windows?

  1. Install mingw64 from https://sourceforge.net/projects/mingw-w64/. Avoid program files/(x86) folder for installation. Ex. c:/mingw-w64
  2. Download pkg-config__win64.zip from here
  3. Extract above zip file and copy paste all the files from pkg-config/bin folder to mingw-w64. In my case its 'C:\mingw-w64\i686-8.1.0-posix-dwarf-rt_v6-rev0\mingw32\bin'
  4. Now set path = C:\mingw-w64\i686-8.1.0-posix-dwarf-rt_v6-rev0\mingw32\bin taddaaa you are done.

If you find any security issue then follow steps as well

  1. Search for windows defender security center in system
  2. Navigate to apps & browser control> Exploit protection settings> Program setting> Click on '+add program customize'
  3. Select add program by name
  4. Enter program name: pkgconf.exe
  5. OK
  6. Now check all the settings and set it all the settings to off and apply.

Thats DONE!

error: (-215) !empty() in function detectMultiScale

"\Anaconda3\Lib\site-packages\cv2\data\" I found the xml file in this path for Anaconda

Python Requests - No connection adapters

You need to include the protocol scheme:

'http://192.168.1.61:8080/api/call'

Without the http:// part, requests has no idea how to connect to the remote server.

Note that the protocol scheme must be all lowercase; if your URL starts with HTTP:// for example, it won’t find the http:// connection adapter either.

AngularJS: Can't I set a variable value on ng-click?

While @tymeJV gave a correct answer, the way to do this to be inline with angular would be:

ng-click="hidePrefs()"

and then in your controller:

$scope.hidePrefs = function() {  
  $scope.prefs = false;
}

How to set IntelliJ IDEA Project SDK

For IntelliJ IDEA 2017.2 I did the following to fix this issue: Go to your project structure enter image description here Now go to SDKs under platform settings and click the green add button. Add your JDK path. In my case it was this path C:\Program Files\Java\jdk1.8.0_144 enter image description here Now Just go Project under Project settings and select the project SDK. enter image description here

How do you run a Python script as a service in Windows?

Yes you can. I do it using the pythoncom libraries that come included with ActivePython or can be installed with pywin32 (Python for Windows extensions).

This is a basic skeleton for a simple service:

import win32serviceutil
import win32service
import win32event
import servicemanager
import socket


class AppServerSvc (win32serviceutil.ServiceFramework):
    _svc_name_ = "TestService"
    _svc_display_name_ = "Test Service"

    def __init__(self,args):
        win32serviceutil.ServiceFramework.__init__(self,args)
        self.hWaitStop = win32event.CreateEvent(None,0,0,None)
        socket.setdefaulttimeout(60)

    def SvcStop(self):
        self.ReportServiceStatus(win32service.SERVICE_STOP_PENDING)
        win32event.SetEvent(self.hWaitStop)

    def SvcDoRun(self):
        servicemanager.LogMsg(servicemanager.EVENTLOG_INFORMATION_TYPE,
                              servicemanager.PYS_SERVICE_STARTED,
                              (self._svc_name_,''))
        self.main()

    def main(self):
        pass

if __name__ == '__main__':
    win32serviceutil.HandleCommandLine(AppServerSvc)

Your code would go in the main() method—usually with some kind of infinite loop that might be interrupted by checking a flag, which you set in the SvcStop method

LINQ to Entities does not recognize the method

As you've figured out, Entity Framework can't actually run your C# code as part of its query. It has to be able to convert the query to an actual SQL statement. In order for that to work, you will have to restructure your query expression into an expression that Entity Framework can handle.

public System.Linq.Expressions.Expression<Func<Charity, bool>> IsSatisfied()
{
    string name = this.charityName;
    string referenceNumber = this.referenceNumber;
    return p => 
        (string.IsNullOrEmpty(name) || 
            p.registeredName.ToLower().Contains(name.ToLower()) ||
            p.alias.ToLower().Contains(name.ToLower()) ||
            p.charityId.ToLower().Contains(name.ToLower())) &&
        (string.IsNullOrEmpty(referenceNumber) ||
            p.charityReference.ToLower().Contains(referenceNumber.ToLower()));
}

Sending JSON to PHP using ajax

If you want to get the values via the $_POST variable then you should not specify the contentType as "application/json" but rather use the default "application/x-www-form-urlencoded; charset=UTF-8":

JavaScript:

var person = { name: "John" };

$.ajax({
    //contentType: "application/json", // php://input
    contentType: "application/x-www-form-urlencoded; charset=UTF-8", // $_POST
    dataType : "json",
    method: "POST",
    url: "http://localhost/test/test.php",
    data: {data: person}
})
.done(function(data) {  
    console.log("test: ", data);
    $("#result").text(data.name);
})
.fail(function(data) {
    console.log("error: ", data);
});

PHP:

<?php

// $_POST

$jsonString = $_POST['data'];

$newJsonString = json_encode($jsonString);
header('Content-Type: application/json');
echo $newJsonString;

Else if you want to send a JSON from JavaScript to PHP:

JavaScript:

var person = { name: "John" };

$.ajax({
    contentType: "application/json", // php://input
    //contentType: "application/x-www-form-urlencoded; charset=UTF-8", // $_POST
    dataType : "json",
    method: "POST",
    url: "http://localhost/test/test.php",
    data: person
})
.done(function(data) {  
    console.log("test: ", data);
    $("#result").text(data.name);
})
.fail(function(data) {
    console.log("error: ", data);
});

PHP:

<?php

$jsonString = file_get_contents("php://input");
$phpObject = json_decode($jsonString);

$newJsonString = json_encode($phpObject);
header('Content-Type: application/json');
echo $newJsonString;

How to set space between listView Items in Android

Simplest solution with OP's existing code (list items already have got padding) is to add following code:

listView.setDivider(new ColorDrawable(Color.TRANSPARENT));  //hide the divider
listView.setClipToPadding(false);   // list items won't clip, so padding stays

This SO answer helped me.

Note: You may face a bug of the list item recycling too soon on older platforms, as has been asked here.

What is an .axd file?

An AXD file is a file used by ASP.NET applications for handling embedded resource requests. It contains instructions for retrieving embedded resources, such as images, JavaScript (.JS) files, and.CSS files. AXD files are used for injecting resources into the client-side webpage and access them on the server in a standard way.

adding x and y axis labels in ggplot2

[Note: edited to modernize ggplot syntax]

Your example is not reproducible since there is no ex1221new (there is an ex1221 in Sleuth2, so I guess that is what you meant). Also, you don't need (and shouldn't) pull columns out to send to ggplot. One advantage is that ggplot works with data.frames directly.

You can set the labels with xlab() and ylab(), or make it part of the scale_*.* call.

library("Sleuth2")
library("ggplot2")
ggplot(ex1221, aes(Discharge, Area)) +
  geom_point(aes(size=NO3)) + 
  scale_size_area() + 
  xlab("My x label") +
  ylab("My y label") +
  ggtitle("Weighted Scatterplot of Watershed Area vs. Discharge and Nitrogen Levels (PPM)")

enter image description here

ggplot(ex1221, aes(Discharge, Area)) +
  geom_point(aes(size=NO3)) + 
  scale_size_area("Nitrogen") + 
  scale_x_continuous("My x label") +
  scale_y_continuous("My y label") +
  ggtitle("Weighted Scatterplot of Watershed Area vs. Discharge and Nitrogen Levels (PPM)")

enter image description here

An alternate way to specify just labels (handy if you are not changing any other aspects of the scales) is using the labs function

ggplot(ex1221, aes(Discharge, Area)) +
  geom_point(aes(size=NO3)) + 
  scale_size_area() + 
  labs(size= "Nitrogen",
       x = "My x label",
       y = "My y label",
       title = "Weighted Scatterplot of Watershed Area vs. Discharge and Nitrogen Levels (PPM)")

which gives an identical figure to the one above.

How to check whether a str(variable) is empty or not?

For python 3, you can use bool()

>>> bool(None)
False
>>> bool("")
False
>>> bool("a")
True
>>> bool("ab")
True
>>> bool("9")
True

Calculate a MD5 hash from a string

Depends entirely on what you are trying to achieve. Technically, you could just take the first 12 characters from the result of the MD5 hash, but the specification of MD5 is to generate a 32 char one.

Reducing the size of the hash reduces the security, and increases the chance of collisions and the system being broken.

Perhaps if you let us know more about what you are trying to achieve we may be able to assist more.

Combine or merge JSON on node.js without jQuery

You should use "Object.assign()"

There's no need to reinvent the wheel for such a simple use case of shallow merging.

The Object.assign() method is used to copy the values of all enumerable own properties from one or more source objects to a target object. It will return the target object.

var o1 = { a: 1 };
var o2 = { b: 2 };
var o3 = { c: 3 };

var obj = Object.assign(o1, o2, o3);
console.log(obj); // { a: 1, b: 2, c: 3 }
console.log(o1);  // { a: 1, b: 2, c: 3 }, target object itself is changed

Even the folks from Node.js say so:

_extend was never intended to be used outside of internal NodeJS modules. The community found and used it anyway. It is deprecated and should not be used in new code. JavaScript comes with very similar built-in functionality through Object.assign.


Update:

You could use the spread operator

Since version 8.6, it's possible to natively use the spread operator in Node.js. Example below:

let o1 = { a: 1 };
let o2 = { b: 2 };
let obj = { ...o1, ...o2 }; // { a: 1, b: 2 }

Object.assign still works, though.


PS1: If you are actually interested in deep merging (in which internal object data -- in any depth -- is recursively merged), you can use packages like deepmerge, assign-deep or lodash.merge, which are pretty small and simple to use.

PS2: Keep in mind that Object.assign doesn't work with 0.X versions of Node.js. If you are working with one of those versions (you really shouldn't by now), you could use require("util")._extend as shown in the Node.js link above -- for more details, check tobymackenzie's answer to this same question.

Get current date in Swift 3?

You say in a comment you want to get "15.09.2016".

For this, use Date and DateFormatter:

let date = Date()
let formatter = DateFormatter()

Give the format you want to the formatter:

formatter.dateFormat = "dd.MM.yyyy"

Get the result string:

let result = formatter.string(from: date)

Set your label:

label.text = result

Result:

15.09.2016

How to set transparent background for Image Button in code?

simply use this in your imagebutton layout

android:background="@null"

using

 android:background="@android:color/transparent 

or

 btn.setBackgroundColor(Color.TRANSPARENT);

doesn't give perfect transparency

Check if a string contains a string in C++

From so many answers in this website I didn't find out a clear answer so in 5-10 minutes I figured it out the answer myself. But this can be done in two cases:

  1. Either you KNOW the position of the sub-string you search for in the string
  2. Either you don't know the position and search for it, char by char...

So, let's assume we search for the substring "cd" in the string "abcde", and we use the simplest substr built-in function in C++

for 1:

#include <iostream>
#include <string>

    using namespace std;
int i;

int main()
{
    string a = "abcde";
    string b = a.substr(2,2);    // 2 will be c. Why? because we start counting from 0 in a string, not from 1.

    cout << "substring of a is: " << b << endl;
    return 0;
}

for 2:

#include <iostream>
#include <string>

using namespace std;
int i;

int main()
{
    string a = "abcde";

    for (i=0;i<a.length(); i++)
    {
        if (a.substr(i,2) == "cd")
        {
        cout << "substring of a is: " << a.substr(i,2) << endl;    // i will iterate from 0 to 5 and will display the substring only when the condition is fullfilled 
        }
    }
    return 0;
}

Best C/C++ Network Library

Aggregated List of Libraries

How to write both h1 and h2 in the same line?

In answer the question heading (found by a google search) and not the re-question To stop the line breaking when you have different heading tags e.g.

<h5 style="display:inline;"> What the... </h5><h1 style="display:inline;"> heck is going on? </h1>

Will give you:

What the...heck is going on?

and not

What the... 
heck is going on?

Is there a way to detect if an image is blurry?

Answers above elucidated many things, but I think it is useful to make a conceptual distinction.

What if you take a perfectly on-focus picture of a blurred image?

The blurring detection problem is only well posed when you have a reference. If you need to design, e.g., an auto-focus system, you compare a sequence of images taken with different degrees of blurring, or smoothing, and you try to find the point of minimum blurring within this set. I other words you need to cross reference the various images using one of the techniques illustrated above (basically--with various possible levels of refinement in the approach--looking for the one image with the highest high-frequency content).

Select All distinct values in a column using LINQ

var uniq = allvalues.GroupBy(x => x.Id).Select(y=>y.First()).Distinct();

Easy and simple

Is there a way to automatically build the package.json file for Node.js projects

npm init

to create the package.json file and then you use

ls node_modules/ | xargs npm install --save

to fill in the modules you have in the node_modules folder.

Edit: @paldepind pointed out that the second command is redundant because npm init now automatically adds what you have in your node_modules/ folder. I don't know if this has always been the case, but now at least, it works without the second command.

SQL Server CASE .. WHEN .. IN statement

Thanks for the Answer I have modified the statements to look like below

SELECT
     AlarmEventTransactionTable.TxnID,
     CASE 
    WHEN DeviceID IN('7', '10', '62', '58', '60',
            '46', '48', '50', '137', '139',
             '141', '145', '164') THEN '01'
    WHEN DeviceID IN('8', '9', '63', '59', '61',
            '47', '49', '51', '138', '140',
            '142', '146', '165') THEN '02'
             ELSE 'NA' END AS clocking,
     AlarmEventTransactionTable.DateTimeOfTxn
FROM
     multiMAXTxn.dbo.AlarmEventTransactionTable

CSS flexbox not working in IE10

IE10 has uses the old syntax. So:

display: -ms-flexbox; /* will work on IE10 */
display: flex; /* is new syntax, will not work on IE10 */

see css-tricks.com/snippets/css/a-guide-to-flexbox:

(tweener) means an odd unofficial syntax from [2012] (e.g. display: flexbox;)

Position last flex item at the end of container

Flexible Box Layout Module - 8.1. Aligning with auto margins

Auto margins on flex items have an effect very similar to auto margins in block flow:

  • During calculations of flex bases and flexible lengths, auto margins are treated as 0.

  • Prior to alignment via justify-content and align-self, any positive free space is distributed to auto margins in that dimension.

Therefore you could use margin-top: auto to distribute the space between the other elements and the last element.

This will position the last element at the bottom.

p:last-of-type {
  margin-top: auto;
}

_x000D_
_x000D_
.container {
  display: flex;
  flex-direction: column;
  border: 1px solid #000;
  min-height: 200px;
  width: 100px;
}
p {
  height: 30px;
  background-color: blue;
  margin: 5px;
}
p:last-of-type {
  margin-top: auto;
}
_x000D_
<div class="container">
  <p></p>
  <p></p>
  <p></p>
</div>
_x000D_
_x000D_
_x000D_

vertical example


Likewise, you can also use margin-left: auto or margin-right: auto for the same alignment horizontally.

p:last-of-type {
  margin-left: auto;
}

_x000D_
_x000D_
.container {
  display: flex;
  width: 100%;
  border: 1px solid #000;
}
p {
  height: 50px;
  width: 50px;
  background-color: blue;
  margin: 5px;
}
p:last-of-type {
  margin-left: auto;
}
_x000D_
<div class="container">
  <p></p>
  <p></p>
  <p></p>
  <p></p>
</div>
_x000D_
_x000D_
_x000D_

horizontal example

convert a char* to std::string

I need to use std::string to store data retrieved by fgets().

Why using fgets() when you are programming C++? Why not std::getline()?

How to make div fixed after you scroll to that div?

Adding on to @Alexandre Aimbiré's answer - sometimes you may need to specify z-index:1 to have the element always on top while scrolling. Like this:

position: -webkit-sticky; /* Safari & IE */
position: sticky;
top: 0;
z-index: 1;

Switching to a TabBar tab view programmatically?

Like Stuart Clark's solution but for Swift 3:

func setTab<T>(_ myClass: T.Type) {
    var i: Int = 0
    if let controllers = self.tabBarController?.viewControllers {
        for controller in controllers {
            if let nav = controller as? UINavigationController, nav.topViewController is T {
                break
            }
            i = i+1
        }
    }
    self.tabBarController?.selectedIndex = i
}

Use it like this:

setTab(MyViewController.self)

Please note that my tabController links to viewControllers behind navigationControllers. Without navigationControllers it would look like this:

if let controller is T {

How can you tell when a layout has been drawn?

An alternative to the usual methods is to hook into the drawing of the view.

OnPreDrawListener is called many times when displaying a view, so there is no specific iteration where your view has valid measured width or height. This requires that you continually verify (view.getMeasuredWidth() <= 0) or set a limit to the number of times you check for a measuredWidth greater than zero.

There is also a chance that the view will never be drawn, which may indicate other problems with your code.

final View view = [ACQUIRE REFERENCE]; // Must be declared final for inner class
ViewTreeObserver viewTreeObserver = view.getViewTreeObserver();
viewTreeObserver.addOnPreDrawListener(new ViewTreeObserver.OnPreDrawListener() {
    @Override
    public boolean onPreDraw() {
        if (view.getMeasuredWidth() > 0) {     
            view.getViewTreeObserver().removeOnPreDrawListener(this);
            int width = view.getMeasuredWidth();
            int height = view.getMeasuredHeight();
            //Do something with width and height here!
        }
        return true; // Continue with the draw pass, as not to stop it
    }
});

How to get position of a certain element in strings vector, to use it as an index in ints vector?

I am a beginner so here is a beginners answer. The if in the for loop gives i which can then be used however needed such as Numbers[i] in another vector. Most is fluff for examples sake, the for/if really says it all.

int main(){
vector<string>names{"Sara", "Harold", "Frank", "Taylor", "Sasha", "Seymore"};
string req_name;
cout<<"Enter search name: "<<'\n';
cin>>req_name;
    for(int i=0; i<=names.size()-1; ++i) {
        if(names[i]==req_name){
            cout<<"The index number for "<<req_name<<" is "<<i<<'\n';
            return 0;
        }
        else if(names[i]!=req_name && i==names.size()-1) {
            cout<<"That name is not an element in this vector"<<'\n';
        } else {
            continue;
        }
    }

how to make password textbox value visible when hover an icon

   <script>
       function seetext(x){
           x.type = "text";
       }
       function seeasterisk(x){
          x.type = "password";
       }
   </script>
  <body>
    <img onmouseover="seetext(a)" onmouseout="seeasterisk(a)" border="0" src="smiley.gif"   alt="Smiley" width="32" height="32">
   <input id = "a" type = "password"/>
 </body>

Try this see if it works

PHPmailer sending HTML CODE

or if you have still problems you can use this

$mail->Body =  html_entity_decode($Body);

Call to a member function on a non-object

It means that $objPage is not an instance of an object. Can we see the code you used to initialize the variable?

As you expect a specific object type, you can also make use of PHPs type-hinting featureDocs to get the error when your logic is violated:

function page_properties(PageAtrributes $objPortal) {    
    ...
    $objPage->set_page_title($myrow['title']);
}

This function will only accept PageAtrributes for the first parameter.

How to make layout with View fill the remaining space?

You can use set the layout_width or layout_width to 0dp (By the orientation you want to fill remaining space). Then use the layout_weight to make it fill remaining space.

How to compile and run C files from within Notepad++ using NppExec plugin?

I recommend my solution. My situation: g++(cygwin) on win10

My solution: Write a .bat batch file and execute compiler in that batch. compileCpp.bat

@echo off  
set PATH=%PATH%;C:\cygwin64\bin\
rm %~n1.exe
c++.exe -g %~dpnx1 -o %~dpn1.exe
%~n1.exe  

Console:

NPP_EXEC: "runCpp"
NPP_SAVE: E:\hw.cpp
CD: E:\
Current directory: E:\
cmd /c C:\cygwin64\bin\compileCpp.bat "hw.cpp"
Process started >>>
Hello World<<< Process finished. (Exit code 0)
================ READY ================

Using Postman to access OAuth 2.0 Google APIs

The current answer is outdated. Here's the up-to-date flow:

The approach outlined here still works (10.12.2020) as confirmed by alexwhan.

We will use the YouTube Data API for our example. Make changes accordingly.

Make sure you have enabled your desired API for your project.

Create the OAuth 2.0 Client

  1. Visit https://console.cloud.google.com/apis/credentials
  2. Click on CREATE CREDENTIALS
  3. Select OAuth client ID
  4. For Application Type choose Web Application
  5. Add a name
  6. Add following URI for Authorized redirect URIs
https://oauth.pstmn.io/v1/callback
  1. Click Save
  2. Click on the OAuth client you just generated
  3. In the Topbar click on DOWNLOAD JSON and save the file somewhere on your machine.

We will use the file later to authenticate Postman.

Authorize Postman via OAuth 2.0 Client

  1. In the Auth tab under TYPE choose OAuth 2.0
  2. For Access Token enter the Access Token found inside the client_secret_[YourClientID].json file we downloaded in step 9
  3. Click on Get New Access Token
  4. Make sure your settings are as follows:

Click here to see the settings

You can find everything else you need in your .json file.

  1. Click on Request Token
  2. A new browser tab/window will open
  3. Once the browser tab opens, login via the appropriate Google account
  4. Accept the consent screen
  5. Done

Ignore the browser message "Not safe" etc. This will be shown until your app has been screened by Google officials. In this case it will always be shown since Postman is the app.

How to round up a number in Javascript?

/**
 * @param num The number to round
 * @param precision The number of decimal places to preserve
 */
function roundUp(num, precision) {
  precision = Math.pow(10, precision)
  return Math.ceil(num * precision) / precision
}

roundUp(192.168, 1) //=> 192.2

How to run a script at a certain time on Linux?

The at command exists specifically for this purpose (unlike cron which is intended for scheduling recurring tasks).

at $(cat file) </path/to/script

How to get a table cell value using jQuery?

$('#mytable tr').each(function() {
  // need this to skip the first row
  if ($(this).find("td:first").length > 0) {
    var cutomerId = $(this).find("td:first").html();
  }
});

Search for one value in any column of any table inside a database

I expanded the code, because it's not told me the 'record number', and I must to refind it.

CREATE PROC SearchAllTables
(
@SearchStr nvarchar(100)
)
AS
BEGIN

-- Copyright © 2002 Narayana Vyas Kondreddi. All rights reserved.
-- Purpose: To search all columns of all tables for a given search string
-- Written by: Narayana Vyas Kondreddi
-- Site: http://vyaskn.tripod.com
-- Tested on: SQL Server 7.0 and SQL Server 2000
-- Date modified: 28th July 2002 22:50 GMT

-- Copyright @ 2012 Gyula Kulifai. All rights reserved.
-- Extended By: Gyula Kulifai
-- Purpose: To put key values, to exactly determine the position of search
-- Resources: Anatoly Lubarsky
-- Date extension: 19th October 2012 12:24 GMT
-- Tested on: SQL Server 10.0.5500 (SQL Server 2008 SP3)

CREATE TABLE #Results (TableName nvarchar(370), KeyValues nvarchar(3630), ColumnName nvarchar(370), ColumnValue nvarchar(3630))

SET NOCOUNT ON

DECLARE @TableName nvarchar(256), @ColumnName nvarchar(128), @SearchStr2 nvarchar(110)
    ,@TableShortName nvarchar(256)
    ,@TableKeys nvarchar(512)
    ,@SQL nvarchar(3830)

SET  @TableName = ''
SET @SearchStr2 = QUOTENAME('%' + @SearchStr + '%','''')

WHILE @TableName IS NOT NULL
BEGIN
    SET @ColumnName = ''

    -- Scan Tables
    SET @TableName = 
    (
        SELECT MIN(QUOTENAME(TABLE_SCHEMA) + '.' + QUOTENAME(TABLE_NAME))
        FROM    INFORMATION_SCHEMA.TABLES
        WHERE       TABLE_TYPE = 'BASE TABLE'
            AND QUOTENAME(TABLE_SCHEMA) + '.' + QUOTENAME(TABLE_NAME) > @TableName
            AND OBJECTPROPERTY(
                    OBJECT_ID(
                        QUOTENAME(TABLE_SCHEMA) + '.' + QUOTENAME(TABLE_NAME)
                         ), 'IsMSShipped'
                           ) = 0
    )
    Set @TableShortName=PARSENAME(@TableName, 1)
    -- print @TableName + ';' + @TableShortName +'!' -- *** DEBUG LINE ***

        -- LOOK Key Fields, Set Key Columns
        SET @TableKeys=''
        SELECT @TableKeys = @TableKeys + '''' + QUOTENAME([name]) + ': '' + CONVERT(nvarchar(250),' + [name] + ') + ''' + ',' + ''' + '
         FROM syscolumns 
         WHERE [id] IN (
            SELECT [id] 
             FROM sysobjects 
             WHERE [name] = @TableShortName)
           AND colid IN (
            SELECT SIK.colid 
             FROM sysindexkeys SIK 
             JOIN sysobjects SO ON 
                SIK.[id] = SO.[id]  
             WHERE 
                SIK.indid = 1
                AND SO.[name] = @TableShortName)
        If @TableKeys<>''
            SET @TableKeys=SUBSTRING(@TableKeys,1,Len(@TableKeys)-8)
        -- Print @TableName + ';' + @TableKeys + '!' -- *** DEBUG LINE ***

    -- Search in Columns
    WHILE (@TableName IS NOT NULL) AND (@ColumnName IS NOT NULL)
    BEGIN
        SET @ColumnName =
        (
            SELECT MIN(QUOTENAME(COLUMN_NAME))
            FROM    INFORMATION_SCHEMA.COLUMNS
            WHERE       TABLE_SCHEMA    = PARSENAME(@TableName, 2)
                AND TABLE_NAME  = PARSENAME(@TableName, 1)
                AND DATA_TYPE IN ('char', 'varchar', 'nchar', 'nvarchar')
                AND QUOTENAME(COLUMN_NAME) > @ColumnName
        ) -- Set ColumnName

        IF @ColumnName IS NOT NULL
        BEGIN
            SET @SQL='
                SELECT 
                    ''' + @TableName + '''
                    ,'+@TableKeys+'
                    ,''' + @ColumnName + '''
                ,LEFT(' + @ColumnName + ', 3630) 
                FROM ' + @TableName + ' (NOLOCK) ' +
                ' WHERE ' + @ColumnName + ' LIKE ' + @SearchStr2
            --Print @SQL -- *** DEBUG LINE ***
            INSERT INTO #Results
                Exec (@SQL)
        END -- IF ColumnName
    END -- While Table and Column
END --While Table

SELECT TableName, KeyValues, ColumnName, ColumnValue FROM #Results
END

jQuery UI Sortable, then write order into a database

This is my example.

https://github.com/luisnicg/jQuery-Sortable-and-PHP

You need to catch the order in the update event

    $( "#sortable" ).sortable({
    placeholder: "ui-state-highlight",
    update: function( event, ui ) {
        var sorted = $( "#sortable" ).sortable( "serialize", { key: "sort" } );
        $.post( "form/order.php",{ 'choices[]': sorted});
    }
});

How to display databases in Oracle 11g using SQL*Plus

I am not clearly about it but typically one server has one database (with many users), if you create many databases mean that you create many instances, listeners, ... as well. So you can check your LISTENER to identify it.

In my testing I created 2 databases (dbtest and dbtest_1) so when I check my LISTENER status it appeared like this:

lsnrctl status

....

STATUS of the LISTENER

.....

(DESCRIPTION=(ADDRESS=(PROTOCOL=tcp)(HOST=10.10.20.20)(PORT=1521)))

Services Summary...

Service "dbtest" has 1 instance(s).

Instance "dbtest", status READY, has 1 handler(s) for this service...

Service "dbtest1XDB" has 1 instance(s).

Instance "dbtest1", status READY, has 1 handler(s) for this service...

Service "dbtest_1" has 1 instance(s).

Instance "dbtest1", status READY, has 1 handler(s) for this service... The command completed successfully

IFrame: This content cannot be displayed in a frame

The X-Frame-Options is defined in the Http Header and not in the <head> section of the page you want to use in the iframe.

Accepted values are: DENY, SAMEORIGIN and ALLOW-FROM "url"

How to semantically add heading to a list

a <div> is a logical division in your content, semantically this would be my first choice if I wanted to group the heading with the list:

<div class="mydiv">
    <h3>The heading</h3>
    <ul>
       <li>item</li>
       <li>item</li>
       <li>item</li>
    </ul>
</div>

then you can use the following css to style everything together as one unit

.mydiv{}
.mydiv h3{}
.mydiv ul{}
.mydiv ul li{}
etc...

Regex number between 1 and 100

Regular Expression for 0 to 100 with the decimal point.

^100(\.[0]{1,2})?|([0-9]|[1-9][0-9])(\.[0-9]{1,2})?$

JAXB: how to marshall map into <key>value</key>

I found easiest solution.

@XmlElement(name="attribute")
    public String[] getAttributes(){
        return attributes.keySet().toArray(new String[1]);
    }
}

Now it will generate in you xml output like this:

<attribute>key1<attribute>
...
<attribute>keyN<attribute>

How can prepared statements protect from SQL injection attacks?

Root Cause #1 - The Delimiter Problem

Sql injection is possible because we use quotation marks to delimit strings and also to be parts of strings, making it impossible to interpret them sometimes. If we had delimiters that could not be used in string data, sql injection never would have happened. Solving the delimiter problem eliminates the sql injection problem. Structure queries do that.

Root Cause #2 - Human Nature, People are Crafty and Some Crafty People Are Malicious And All People Make Mistakes

The other root cause of sql injection is human nature. People, including programmers, make mistakes. When you make a mistake on a structured query, it does not make your system vulnerable to sql injection. If you are not using structured queries, mistakes can generate sql injection vulnerability.

How Structured Queries Resolve the Root Causes of SQL Injection

Structured Queries Solve The Delimiter Problem, by by putting sql commands in one statement and putting the data in a separate programming statement. Programming statements create the separation needed.

Structured queries help prevent human error from creating critical security holes. With regard to humans making mistakes, sql injection cannot happen when structure queries are used. There are ways of preventing sql injection that don't involve structured queries, but normal human error in that approaches usually leads to at least some exposure to sql injection. Structured Queries are fail safe from sql injection. You can make all the mistakes in the world, almost, with structured queries, same as any other programming, but none that you can make can be turned into a ssstem taken over by sql injection. That is why people like to say this is the right way to prevent sql injection.

So, there you have it, the causes of sql injection and the nature structured queries that makes them impossible when they are used.

How to get city name from latitude and longitude coordinates in Google Maps?

Try this

var geocoder;
geocoder = new google.maps.Geocoder();
var latlng = new google.maps.LatLng(latitude, longitude);

geocoder.geocode(
{'latLng': latlng}, 
function(results, status) {
    if (status == google.maps.GeocoderStatus.OK) {
            if (results[0]) {
                var add= results[0].formatted_address ;
                var  value=add.split(",");

                count=value.length;
                country=value[count-1];
                state=value[count-2];
                city=value[count-3];
                alert("city name is: " + city);
            }
            else  {
                alert("address not found");
            }
    }
     else {
        alert("Geocoder failed due to: " + status);
    }
}

);

Add missing dates to pandas dataframe

A quicker workaround is to use .asfreq(). This doesn't require creation of a new index to call within .reindex().

# "broken" (staggered) dates
dates = pd.Index([pd.Timestamp('2012-05-01'), 
                  pd.Timestamp('2012-05-04'), 
                  pd.Timestamp('2012-05-06')])
s = pd.Series([1, 2, 3], dates)

print(s.asfreq('D'))
2012-05-01    1.0
2012-05-02    NaN
2012-05-03    NaN
2012-05-04    2.0
2012-05-05    NaN
2012-05-06    3.0
Freq: D, dtype: float64

Passing a String by Reference in Java?

This works use StringBuffer

public class test {
 public static void main(String[] args) {
 StringBuffer zText = new StringBuffer("");
    fillString(zText);
    System.out.println(zText.toString());
 }
  static void fillString(StringBuffer zText) {
    zText .append("foo");
}
}

Even better use StringBuilder

public class test {
 public static void main(String[] args) {
 StringBuilder zText = new StringBuilder("");
    fillString(zText);
    System.out.println(zText.toString());
 }
  static void fillString(StringBuilder zText) {
    zText .append("foo");
}
}

proper way to logout from a session in PHP

Session_unset(); only destroys the session variables. To end the session there is another function called session_destroy(); which also destroys the session .

update :

In order to kill the session altogether, like to log the user out, the session id must also be unset. If a cookie is used to propagate the session id (default behavior), then the session cookie must be deleted. setcookie() may be used for that

Display array values in PHP

use implode(',', $array); for output as apple,banana,orange

Or

foreach($array as $key => $value)
{
   echo $key." is ". $value;
}

Jquery and HTML FormData returns "Uncaught TypeError: Illegal invocation"

In my case, there was a mistake in the list of the parameters was not well formed. So make sure the parameters are well formed. For e.g. correct format of parameters

data: {'reporter': reporter,'partner': partner,'product': product}

Find the line number where a specific word appears with "grep"

You can call tail +[line number] [file] and pipe it to grep -n which shows the line number:

tail +[line number] [file] | grep -n /regex/

The only problem with this method is the line numbers reported by grep -n will be [line number] - 1 less than the actual line number in [file].

Uncaught TypeError: Cannot read property 'msie' of undefined

$.browser was removed from jQuery starting with version 1.9. It is now available as a plugin. It's generally recommended to avoid browser detection, which is why it was removed.

How to solve Notice: Undefined index: id in C:\xampp\htdocs\invmgt\manufactured_goods\change.php on line 21

Simply add this

$id = ''; 
if( isset( $_GET['id'])) {
    $id = $_GET['id']; 
} 

Is it possible to have a HTML SELECT/OPTION value as NULL using PHP?

All you need is a check on the post side of things.

if(empty($_REQUEST['type_id']) && $_REQUEST['type_id'] != 0)
    $_REQUEST['type_id'] = null;