Programs & Examples On #Chm

CHM is the proprietary help file format generated by Microsoft HTMLHelp Workshop (hhw.exe). It's HTML based help, so topics are required in HTML and supplemented by the used *.jpg, *.gif or e.g. *.svg files. Some additional files for the table of contents (.HHC)and index (.HHK) must be created. The .HHP file is needed for the Workshop project itself. HTMLHelp (HH) was first shipped with Internet Explorer 4 and Windows 95.

Opening a CHM file produces: "navigation to the webpage was canceled"

Go to Start

Type regsvr32 hhctrl.ocx

You should get a success message like:

" DllRegisterServer in hhctrl.ocx succeeded "

Now try to open your CHM file again.

Collection was modified; enumeration operation may not execute in ArrayList

Instead of foreach(), use a for() loop with a numeric index.

Getting visitors country from their IP

I have a short answer which I have used in a project. In my answer, I consider that you have visitor IP address.

$ip = "202.142.178.220";
$ipdat = @json_decode(file_get_contents("http://www.geoplugin.net/json.gp?ip=" . $ip));
//get ISO2 country code
if(property_exists($ipdat, 'geoplugin_countryCode')) {
    echo $ipdat->geoplugin_countryCode;
}
//get country full name
if(property_exists($ipdat, 'geoplugin_countryName')) {
    echo $ipdat->geoplugin_countryName;
}

How to allow CORS in react.js?

Suppose you want to hit https://yourwebsitedomain/app/getNames from http://localhost:3000 then just make the following changes:

packagae.json :

   "name": "version-compare-app",
   "proxy": "https://yourwebsitedomain/",
   ....
   "dependencies": {
    "@testing-library/jest-dom": "^4.2.4",
    "@testing-library/react": "^9.5.0",
     ...

In your component use it as follows:

import axios from "axios";

componentDidMount() {
const getNameUrl =
  "app/getNames";

axios.get(getChallenge).then(data => {
  console.log(data);
});

}

Stop your local server and re run npm start. You should be able to see the data in browser's console logged

How to execute a bash command stored as a string with quotes and asterisk

To eliminate the need for the cmd variable, you can do this:

eval 'mysql AMORE -u root --password="password" -h localhost -e "select host from amoreconfig"'

Print range of numbers on same line

[print(i, end = ' ') for i in range(10)]
0 1 2 3 4 5 6 7 8 9

This is a list comprehension method of answer same as @Anubhav

Run certain code every n seconds

def update():
    import time
    while True:
        print 'Hello World!'
        time.sleep(5)

That'll run as a function. The while True: makes it run forever. You can always take it out of the function if you need.

git push >> fatal: no configured push destination

You are referring to the section "2.3.5 Deploying the demo app" of this "Ruby on Rails Tutorial ":

In section 2.3.1 Planning the application, note that they did:

$ git remote add origin [email protected]:<username>/demo_app.git
$ git push origin master

That is why a simple git push worked (using here an ssh address).
Did you follow that step and made that first push?

 www.github.com/levelone/demo_app

wouldn't be a writable URI for pushing to a GitHub repo.

https://[email protected]/levelone/demo_app.git

should be more appropriate.
Check what git remote -v returns, and if you need to replace the remote address, as described in GitHub help page, use git remote --set-url.

git remote set-url origin https://[email protected]/levelone/demo_app.git
or 
git remote set-url origin [email protected]:levelone/demo_app.git

Volley - POST/GET parameters

For the GET parameters there are two alternatives:

First: As suggested in a comment bellow the question you can just use String and replace the parameters placeholders with their values like:

String uri = String.format("http://somesite.com/some_endpoint.php?param1=%1$s&param2=%2$s",
                           num1,
                           num2);

StringRequest myReq = new StringRequest(Method.GET,
                                        uri,
                                        createMyReqSuccessListener(),
                                        createMyReqErrorListener());
queue.add(myReq);

where num1 and num2 are String variables that contain your values.

Second: If you are using newer external HttpClient (4.2.x for example) you can use URIBuilder to build your Uri. Advantage is that if your uri string already has parameters in it it will be easier to pass it to the URIBuilder and then use ub.setQuery(URLEncodedUtils.format(getGetParams(), "UTF-8")); to add your additional parameters. That way you will not bother to check if "?" is already added to the uri or to miss some & thus eliminating a source for potential errors.

For the POST parameters probably sometimes will be easier than the accepted answer to do it like:

StringRequest myReq = new StringRequest(Method.POST,
                                        "http://somesite.com/some_endpoint.php",
                                        createMyReqSuccessListener(),
                                        createMyReqErrorListener()) {

    protected Map<String, String> getParams() throws com.android.volley.AuthFailureError {
        Map<String, String> params = new HashMap<String, String>();
        params.put("param1", num1);
        params.put("param2", num2);
        return params;
    };
};
queue.add(myReq);

e.g. to just override the getParams() method.

You can find a working example (along with many other basic Volley examples) in the Andorid Volley Examples project.

Most efficient method to groupby on an array of objects

You can do it with Alasql JavaScript library:

var data = [ { Phase: "Phase 1", Step: "Step 1", Task: "Task 1", Value: "5" },
             { Phase: "Phase 1", Step: "Step 1", Task: "Task 2", Value: "10" }];

var res = alasql('SELECT Phase, Step, SUM(CAST([Value] AS INT)) AS [Value] \
                  FROM ? GROUP BY Phase, Step',[data]);

Try this example at jsFiddle.

BTW: On large arrays (100000 records and more) Alasql faster tham Linq. See test at jsPref.

Comments:

  • Here I put Value in square brackets, because VALUE is a keyword in SQL
  • I have to use CAST() function to convert string Values to number type.

Python ValueError: too many values to unpack

self.materials is a dict and by default you are iterating over just the keys (which are strings).

Since self.materials has more than two keys*, they can't be unpacked into the tuple "k, m", hence the ValueError exception is raised.

In Python 2.x, to iterate over the keys and the values (the tuple "k, m"), we use self.materials.iteritems().

However, since you're throwing the key away anyway, you may as well simply iterate over the dictionary's values:

for m in self.materials.itervalues():

In Python 3.x, prefer dict.values() (which returns a dictionary view object):

for m in self.materials.values():

What is the difference between JavaScript and ECMAScript?

What is ECMAScript i.e. ES?

ECMAScript is a standard for a scripting language and the Javascript language is based on the ECMAScript standard.

Is Javascript exactly the same as ECMAScript?

  • No, Javascript is not exactly equivalent to ECMAScript.
  • The core features of Javascript are based on the ECMAScript standard, but Javascript also has other additional features that are not in the ECMA specifications/standard.

JavaScript = ECMAScript + DOM API;

DOM API like: document.getElementById('id');

Do other languages use the ECMAScript standard?

  • Yes, there are languages other than JavaScript that also implement the ECMAScript Standard as their core.
  • ActionScript (used by Adobe Flash) and JScript (used by Microsoft) are both languages that implement the ECMAScript standard.

Why is it called ECMAScript?

  • Javascript was originally created at Netscape, and they wanted to standardize the language. So, they submitted the language to the European Computer Manufacturer’s Association (ECMA) for standardization.
  • But, there were trademark issues with the name Javascript, and the standard became called ECMAScript, which is the name it holds today as well.
  • Because of trademark issues, Microsoft’s version of the language is called JScript – even though JScript is, at its core, the same language as Javascript.

Catch a thread's exception in the caller thread in Python

What im doing is, simple overriding join and run method of the Thread:

class RaisingThread(threading.Thread):
  def run(self):
    self._exc = None
    try:
      super().run()
    except Exception as e:
      self._exc = e

  def join(self):
    super().join()
    if self._exc:
      raise self._exc

Used as followed:

def foo():
  time.sleep(2)
  print('hi, from foo!')
  raise Exception('exception from foo')    

t = RaisingThread(target=foo)
t.start()
try:
  t.join()
except Exception as e:
  print(e)

Result:

hi, from foo!
exception from foo!

Html5 Placeholders with .NET MVC 3 Razor EditorFor extension?

I've wrote such a simple class:

public static class WatermarkExtension
{
    public static MvcHtmlString WatermarkFor<TModel, TValue>(this HtmlHelper<TModel> html, Expression<Func<TModel, TValue>> expression)
    {
        var watermark = ModelMetadata.FromLambdaExpression(expression, html.ViewData).Watermark;
        var htmlEncoded = HttpUtility.HtmlEncode(watermark);
        return new MvcHtmlString(htmlEncoded);
    }
}

The usage as such:

@Html.TextBoxFor(model => model.AddressSuffix, new {placeholder = Html.WatermarkFor(model => model.AddressSuffix)})

And property in a viewmodel:

[Display(ResourceType = typeof (Resources), Name = "AddressSuffixLabel", Prompt = "AddressSuffixPlaceholder")]
public string AddressSuffix
{
    get { return _album.AddressSuffix; }
    set { _album.AddressSuffix = value; }
}

Notice Prompt parameter. In this case I use strings from resources for localization but you can use just strings, just avoid ResourceType parameter.

Securely storing passwords for use in python script

Know the master key yourself. Don't hard code it.

Use py-bcrypt (bcrypt), powerful hashing technique to generate a password yourself.

Basically you can do this (an idea...)

import bcrypt
from getpass import getpass
master_secret_key = getpass('tell me the master secret key you are going to use')
salt = bcrypt.gensalt()
combo_password = raw_password + salt + master_secret_key
hashed_password = bcrypt.hashpw(combo_password, salt)

save salt and hashed password somewhere so whenever you need to use the password, you are reading the encrypted password, and test against the raw password you are entering again.

This is basically how login should work these days.

How to find the minimum value of a column in R?

If you prefer using column names, you could do something like this as an alternative:

min(data$column_name)

How do I get a list of all subdomains of a domain?

If the DNS server is configured properly, you won't be able to get the entire domain. If for some reason is allows zone transfers from any host, you'll have to send it the correct packet to make that request. I suspect that's what the dig statement you included does.

How to embed a YouTube channel into a webpage

In order to embed your channel, all you need to do is copy then paste the following code in another web-page.

<script src="http://www.gmodules.com/ig/ifr?url=http://www.google.com/ig/modules/youtube.xml&up_channel=YourChannelName&synd=open&w=320&h=390&title=&border=%23ffffff%7C3px%2C1px+solid+%23999999&output=js"></script>

Make sure to replace the YourChannelName with your actual channel name.

For example: if your channel name were CaliChick94066 your channel embed code would be:

<script src="http://www.gmodules.com/ig/ifr?url=http://www.google.com/ig/modules/youtube.xml&up_channel=CaliChick94066&synd=open&w=320&h=390&title=&border=%23ffffff%7C3px%2C1px+solid+%23999999&output=js"></script>

Please look at the following links:

YouTube on your site

Embed YouTube Channel

You just have to name the URL to your channel name. Also you can play with the height and the border color and size. Hope it helps

Error in your SQL syntax; check the manual that corresponds to your MySQL server version

Use ` backticks for MYSQL reserved words...

table name "table" is reserved word for MYSQL...

so your query should be as follows...

$sql="INSERT INTO `table` (`username`, `password`)
VALUES
('$_POST[username]','$_POST[password]')";

How to justify a single flexbox item (override justify-content)

If you aren't actually restricted to keeping all of these elements as sibling nodes you can wrap the ones that go together in another default flex box, and have the container of both use space-between.

_x000D_
_x000D_
.space-between {_x000D_
  border: 1px solid red;_x000D_
  display: flex;_x000D_
  justify-content: space-between;_x000D_
}_x000D_
.default-flex {_x000D_
  border: 1px solid blue;_x000D_
  display: flex;_x000D_
}_x000D_
.child {_x000D_
  width: 100px;_x000D_
  height: 100px;_x000D_
  border: 1px solid;_x000D_
}
_x000D_
<div class="space-between">_x000D_
  <div class="child">1</div>_x000D_
  <div class="default-flex">_x000D_
    <div class="child">2</div>_x000D_
    <div class="child">3</div>_x000D_
    <div class="child">4</div>_x000D_
    <div class="child">5</div>_x000D_
  </div>_x000D_
</div>
_x000D_
_x000D_
_x000D_

Or if you were doing the same thing with flex-start and flex-end reversed you just swap the order of the default-flex container and lone child.

Python 2,3 Convert Integer to "bytes" Cleanly

Answer 1:

To convert a string to a sequence of bytes in either Python 2 or Python 3, you use the string's encode method. If you don't supply an encoding parameter 'ascii' is used, which will always be good enough for numeric digits.

s = str(n).encode()

In Python 2 str(n) already produces bytes; the encode will do a double conversion as this string is implicitly converted to Unicode and back again to bytes. It's unnecessary work, but it's harmless and is completely compatible with Python 3.


Answer 2:

Above is the answer to the question that was actually asked, which was to produce a string of ASCII bytes in human-readable form. But since people keep coming here trying to get the answer to a different question, I'll answer that question too. If you want to convert 10 to b'10' use the answer above, but if you want to convert 10 to b'\x0a\x00\x00\x00' then keep reading.

The struct module was specifically provided for converting between various types and their binary representation as a sequence of bytes. The conversion from a type to bytes is done with struct.pack. There's a format parameter fmt that determines which conversion it should perform. For a 4-byte integer, that would be i for signed numbers or I for unsigned numbers. For more possibilities see the format character table, and see the byte order, size, and alignment table for options when the output is more than a single byte.

import struct
s = struct.pack('<i', 5) # b'\x05\x00\x00\x00'

Display A Popup Only Once Per User

This example uses jquery-cookie

Check if the cookie exists and has not expired - if either of those fails, then show the popup and set the cookie (Semi pseudo code):

if($.cookie('popup') != 'seen'){
    $.cookie('popup', 'seen', { expires: 365, path: '/' }); // Set it to last a year, for example.
    $j("#popup").delay(2000).fadeIn();
    $j('#popup-close').click(function(e) // You are clicking the close button
        {
        $j('#popup').fadeOut(); // Now the pop up is hiden.
    });
    $j('#popup').click(function(e) 
        {
        $j('#popup').fadeOut(); 
    });
};

Check if a string matches a regex in Bash script

You can use the test construct, [[ ]], along with the regular expression match operator, =~, to check if a string matches a regex pattern.

For your specific case, you can write:

[[ $date =~ ^[0-9]{8}$ ]] && echo "yes"

Or more a accurate test:

[[ $date =~ ^[0-9]{4}(0[1-9]|1[0-2])(0[1-9]|[1-2][0-9]|3[0-1])$ ]] && echo "yes"
#           |^^^^^^^^ ^^^^^^ ^^^^^^  ^^^^^^ ^^^^^^^^^^ ^^^^^^ |
#           |   |     ^^^^^^^^^^^^^  ^^^^^^^^^^^^^^^^^^^^^^^^ |
#           |   |          |                   |              |
#           |   |           \                  |              |
#           | --year--   --month--           --day--          |
#           |          either 01...09      either 01..09     end of line
# start of line            or 10,11,12         or 10..29
#                                              or 30, 31

That is, you can define a regex in Bash matching the format you want. This way you can do:

[[ $date =~ ^regex$ ]] && echo "matched" || echo "did not match"

where commands after && are executed if the test is successful, and commands after || are executed if the test is unsuccessful.

Note this is based on the solution by Aleks-Daniel Jakimenko in User input date format verification in bash.


In other shells you can use grep. If your shell is POSIX compliant, do

(echo "$date" | grep -Eq  ^regex$) && echo "matched" || echo "did not match"

In fish, which is not POSIX-compliant, you can do

echo "$date" | grep -Eq "^regex\$"; and echo "matched"; or echo "did not match"

scroll image with continuous scrolling using marquee tag

I think you set the marquee width related to 5 images total width. It works fine

ex: <marquee style="width:700px"></marquee>

How do I get the value of text input field using JavaScript?

If your input is in a form and you want to get value after submit you can do like

<form onsubmit="submitLoginForm(event)">
    <input type="text" name="name">
    <input type="password" name="password">
    <input type="submit" value="Login">
</form>

<script type="text/javascript">

    function submitLoginForm(event){
        event.preventDefault();

        console.log(event.target['name'].value);
        console.log(event.target['password'].value);
    }
</script>

Benefit of this way: Example your page have 2 form for input sender and receiver information.

If you don't use form for get value then
- You can set 2 different id(or tag or name ...) for each field like sender-name and receiver-name, sender-address and receiver-address, ...
- If you set same value for 2 input, then after getElementsByName (or getElementsByTagName ...) you need to remember 0 or 1 is sender or receiver. Later if you change the order of 2 form in html, you need to check this code again

If you use form, then you can use name, address, ...

Unzip files (7-zip) via cmd command

make sure that your path is pointing to .exe file in C:\Program Files\7-Zip (may in bin directory)

twig: IF with multiple conditions

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

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

Expressions

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

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

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

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

How to unblock with mysqladmin flush hosts

mysqladmin is not a SQL statement. It's a little helper utility program you'll find on your MySQL server... and "flush-hosts" is one of the things it can do. ("status" and "shutdown" are a couple of other things that come to mind).

You type that command from a shell prompt.

Alternately, from your query browser (such as phpMyAdmin), the SQL statement you're looking for is simply this:

FLUSH HOSTS;

http://dev.mysql.com/doc/refman/5.6/en/flush.html

http://dev.mysql.com/doc/refman/5.6/en/mysqladmin.html

PHP Warning: PHP Startup: Unable to load dynamic library

Look for the exact extension for your PHP version here

UnicodeEncodeError: 'ascii' codec can't encode character u'\xa0' in position 20: ordinal not in range(128)

I found elegant work around for me to remove symbols and continue to keep string as string in follows:

yourstring = yourstring.encode('ascii', 'ignore').decode('ascii')

It's important to notice that using the ignore option is dangerous because it silently drops any unicode(and internationalization) support from the code that uses it, as seen here (convert unicode):

>>> u'City: Malmö'.encode('ascii', 'ignore').decode('ascii')
'City: Malm'

HTML5 video won't play in Chrome only

Try this

<video autoplay loop id="video-background" muted plays-inline>
            <source src="https://player.vimeo.com/external/158148793.hd.mp4?s=8e8741dbee251d5c35a759718d4b0976fbf38b6f&profile_id=119&oauth2_token_id=57447761" type="video/mp4">
            </video>

Thanks

ValueError: object too deep for desired array while using convolution

np.convolve needs a flattened array as one of it's inputs, you can use numpy.ndarray.flatten() which is quite fast, find it here.

how to convert image to byte array in java?

BufferedImage consists of two main classes: Raster & ColorModel. Raster itself consists of two classes, DataBufferByte for image content while the other for pixel color.

if you want the data from DataBufferByte, use:

public byte[] extractBytes (String ImageName) throws IOException {
 // open image
 File imgPath = new File(ImageName);
 BufferedImage bufferedImage = ImageIO.read(imgPath);

 // get DataBufferBytes from Raster
 WritableRaster raster = bufferedImage .getRaster();
 DataBufferByte data   = (DataBufferByte) raster.getDataBuffer();

 return ( data.getData() );
}

now you can process these bytes by hiding text in lsb for example, or process it the way you want.

Java - Access is denied java.io.FileNotFoundException

When you create a new File, you are supposed to provide the file name, not only the directory you want to put your file in.

Try with something like

File file = new File("D:/Data/" + item.getFileName());

How do I scroll to an element using JavaScript?

You can use an anchor to "focus" the div. I.e:

<div id="myDiv"></div>

and then use the following javascript:

// the next line is required to work around a bug in WebKit (Chrome / Safari)
location.href = "#";
location.href = "#myDiv";

How to include quotes in a string

Escape them with backslashes.

"I want to learn \"C#\""

Request Monitoring in Chrome

Open up your DevTools and press F1 to access the settings. Look for the console section and check the checkbox for "Log XMLHttpRequests".

Now all of your ajax and other similar requests will be logged in the console.

I prefer this method because it usually allows me to see everything that I'm looking for in the console without having to go to the network tab.

Aligning text and image on UIButton with imageEdgeInsets and titleEdgeInsets

In Xcode 8.0 you can simply do it by changing insets in size inspector.

Select the UIButton -> Attributes Inspector -> go to size inspector and modify the content, image and title insets.

enter image description here

And if you want to change image on right side you can simply change the semantic property to Force Right-to-left in Attribute inspector .

enter image description here

What does #defining WIN32_LEAN_AND_MEAN exclude exactly?

According the to Windows Dev Center WIN32_LEAN_AND_MEAN excludes APIs such as Cryptography, DDE, RPC, Shell, and Windows Sockets.

Model summary in pytorch

You can just use x.shape, in order to measure tensor's x dimensions

Can a Byte[] Array be written to a file in C#?

Based on the first sentence of the question: "I'm trying to write out a Byte[] array representing a complete file to a file."

The path of least resistance would be:

File.WriteAllBytes(string path, byte[] bytes)

Documented here:

System.IO.File.WriteAllBytes - MSDN

Capturing "Delete" Keypress with jQuery

event.key === "Delete"

More recent and much cleaner: use event.key. No more arbitrary number codes!

NOTE: The old properties (.keyCode and .which) are Deprecated.

document.addEventListener('keydown', function(event) {
    const key = event.key; // const {key} = event; ES6+
    if (key === "Delete") {
        // Do things
    }
});

Mozilla Docs

Supported Browsers

Writing a string to a cell in excel

replace Range("A1") = "Asdf" with Range("A1").value = "Asdf"

WPF MVVM: How to close a window

I just completed a blog post on this very topic. In a nutshell, add an Action property to your ViewModel with get and set accessors. Then define the Action from your View constructor. Finally, invoke your action in the bound command that should close the window.

In the ViewModel:

public Action CloseAction  { get; set;}

and in the View constructor:

private View()
{
    InitializeComponent();
    ViewModel vm = new ViewModel();
    this.DataContext = vm;
    if ( vm.CloseAction == null )
        vm.CloseAction = new Action(this.Close);
}

Finally, in whatever bound command that should close the window, we can simply invoke

CloseAction(); // Calls Close() method of the View

This worked for me, seemed like a fairly elegant solution, and saved me a bunch of coding.

How to display full (non-truncated) dataframe information in html when converting from pandas dataframe to html?

The following code results in the error below:

pd.set_option('display.max_colwidth', -1)

FutureWarning: Passing a negative integer is deprecated in version 1.0 and will not be supported in future version. Instead, use None to not limit the column width.

Instead, use:

pd.set_option('display.max_colwidth', None)

This accomplishes the task and complies with versions of pandas following version 1.0.

npm - how to show the latest version of a package

You can see all the version of a module with npm view. eg: To list all versions of bootstrap including beta.

npm view bootstrap versions

But if the version list is very big it will truncate. An --json option will print all version including beta versions as well.

npm view bootstrap versions --json

If you want to list only the stable versions not the beta then use singular version

npm view bootstrap@* versions

Or

npm view bootstrap@* versions --json

And, if you want to see only latest version then here you go.

npm view bootstrap version

glob exclude pattern

Compare with glob, I recommend pathlib, filter one pattern is very simple.

from pathlib import Path

p = Path(YOUR_PATH)
filtered = [x for x in p.glob("**/*") if not x.name.startswith("eph")]

and if you want to filter more complex pattern, you can define a function to do that, just like:

def not_in_pattern(x):
    return (not x.name.startswith("eph")) and not x.name.startswith("epi")


filtered = [x for x in p.glob("**/*") if not_in_pattern(x)]

use that code, you can filter all files that start with eph or start with epi.

How can I permanently enable line numbers in IntelliJ?

IntelliJ IDEA 15

5 approaches


Global change

  1. File > Settings... > Editor > General > Appearance > Show line numbers

    show line numbers

  2. Hit Shift twice > write "line numbers" > Show Line Numbers (that one that has the toggle) > change the toggle to ON

    shift shift


Change for the Active Editor

  1. Right click on the left side bar > Show Line Numbers

    right click

  2. Hit Shift twice > write "line" > Show Line Numbers (the line doesn't have the toggle)

    shift shift line

  3. Ctrl + Shift + A > write "Show line" > Active Editor: Show Line Numbers > change the toggle to ON

    Ctrl Shift A

Location of GlassFish Server Logs

tail -f /path/to/glassfish/domains/YOURDOMAIN/logs/server.log

You can also upload log from admin console : http://yoururl:4848

enter image description here

Boolean operators && and ||

The answer about "short-circuiting" is potentially misleading, but has some truth (see below). In the R/S language, && and || only evaluate the first element in the first argument. All other elements in a vector or list are ignored regardless of the first ones value. Those operators are designed to work with the if (cond) {} else{} construction and to direct program control rather than construct new vectors.. The & and the | operators are designed to work on vectors, so they will be applied "in parallel", so to speak, along the length of the longest argument. Both vectors need to be evaluated before the comparisons are made. If the vectors are not the same length, then recycling of the shorter argument is performed.

When the arguments to && or || are evaluated, there is "short-circuiting" in that if any of the values in succession from left to right are determinative, then evaluations cease and the final value is returned.

> if( print(1) ) {print(2)} else {print(3)}
[1] 1
[1] 2
> if(FALSE && print(1) ) {print(2)} else {print(3)} # `print(1)` not evaluated
[1] 3
> if(TRUE && print(1) ) {print(2)} else {print(3)}
[1] 1
[1] 2
> if(TRUE && !print(1) ) {print(2)} else {print(3)}
[1] 1
[1] 3
> if(FALSE && !print(1) ) {print(2)} else {print(3)}
[1] 3

The advantage of short-circuiting will only appear when the arguments take a long time to evaluate. That will typically occur when the arguments are functions that either process larger objects or have mathematical operations that are more complex.

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

You can use Case Insensitive Indexes:

The following example creates a collection with no default collation, then adds an index on the name field with a case insensitive collation. International Components for Unicode

/* strength: CollationStrength.Secondary
* Secondary level of comparison. Collation performs comparisons up to secondary * differences, such as diacritics. That is, collation performs comparisons of 
* base characters (primary differences) and diacritics (secondary differences). * Differences between base characters takes precedence over secondary 
* differences.
*/
db.users.createIndex( { name: 1 }, collation: { locale: 'tr', strength: 2 } } )

To use the index, queries must specify the same collation.

db.users.insert( [ { name: "Oguz" },
                            { name: "oguz" },
                            { name: "OGUZ" } ] )

// does not use index, finds one result
db.users.find( { name: "oguz" } )

// uses the index, finds three results
db.users.find( { name: "oguz" } ).collation( { locale: 'tr', strength: 2 } )

// does not use the index, finds three results (different strength)
db.users.find( { name: "oguz" } ).collation( { locale: 'tr', strength: 1 } )

or you can create a collection with default collation:

db.createCollection("users", { collation: { locale: 'tr', strength: 2 } } )
db.users.createIndex( { name : 1 } ) // inherits the default collation

How to extract a single value from JSON response?

Only suggestion is to access your resp_dict via .get() for a more graceful approach that will degrade well if the data isn't as expected.

resp_dict = json.loads(resp_str)
resp_dict.get('name') # will return None if 'name' doesn't exist

You could also add some logic to test for the key if you want as well.

if 'name' in resp_dict:
    resp_dict['name']
else:
    # do something else here.

Check if a list contains an item in Ansible

You do not need {{}} in when conditions. What you are searching for is:

- fail: msg="unsupported version"
  when: version not in acceptable_versions

Number of regex matches

For those moments when you really want to avoid building lists:

import re
import operator
from functools import reduce
count = reduce(operator.add, (1 for _ in re.finditer(my_pattern, my_string))) 

Sometimes you might need to operate on huge strings. This might help.

Convert from days to milliseconds

24 hours = 86400 seconds = 86400000 milliseconds. Just multiply your number with 86400000.

How to add a ScrollBar to a Stackpanel

It works like this:

<ScrollViewer VerticalScrollBarVisibility="Visible" HorizontalScrollBarVisibility="Disabled" Width="340" HorizontalAlignment="Left" Margin="12,0,0,0">
        <StackPanel Name="stackPanel1" Width="311">

        </StackPanel>
</ScrollViewer>

TextBox tb = new TextBox();
tb.TextChanged += new TextChangedEventHandler(TextBox_TextChanged);
stackPanel1.Children.Add(tb);

Freeze screen in chrome debugger / DevTools panel for popover inspection?

UPDATE: As Brad Parks wrote in his comment there is a much better and easier solution with only one line of JS code:

run setTimeout(function(){debugger;},5000);, then go show your element and wait until it breaks into the Debugger


Original answer:

I just had the same problem, and I think I found an "universal" solution. (assuming the site uses jQuery)
Hope it helps someone!

  1. Go to elements tab in inspector
  2. Right click <body> and click "Edit as HTML"
  3. Add the following element after <body> then press Ctrl+Enter:
    <div id="debugFreeze" data-rand="0"></div>
  4. Right click this new element, and select "Break on..." -> "Attributes modifications"
  5. Now go to Console view and run the following command:
    setTimeout(function(){$("#debugFreeze").attr("data-rand",Math.random())},5000);
  6. Now go back to the browser window and you have 5 seconds to find your element and click/hover/focus/etc it, before the breakpoint will be hit and the browser will "freeze".
  7. Now you can inspect your clicked/hovered/focused/etc element in peace.

Of course you can modify the javascript and the timing, if you get the idea.

java.lang.NoClassDefFoundError: org/apache/http/client/HttpClient

I have solved this problem by importing the following dependency. you must manually import httpclient

<dependency>
    <groupId>commons-httpclient</groupId>
    <artifactId>commons-httpclient</artifactId>
    <version>3.1</version>
    <exclusions>
        <exclusion>
            <groupId>commons-logging</groupId>
            <artifactId>*</artifactId>
        </exclusion>
    </exclusions>
</dependency>

Make div (height) occupy parent remaining height

Abstract

I didn't find a fully satisfying answer so I had to find it out myself.

My requirements:

  • the element should take exactly the remaining space either when its content size is smaller or bigger than the remaining space size (in the second case scrollbar should be shown);
  • the solution should work when the parent height is computed, and not specified;
  • calc() should not be used as the remaining element shouldn't know anything about another element sizes;
  • modern and familar layout technique such as flexboxes should be used.

The solution

  • Turn into flexboxes all direct parents with computed height (if any) and the next parent whose height is specified;
  • Specify flex-grow: 1 to all direct parents with computed height (if any) and the element so they will take up all remaining space when the element content size is smaller;
  • Specify flex-shrink: 0 to all flex items with fixed height so they won't become smaller when the element content size is bigger than the remaining space size;
  • Specify overflow: hidden to all direct parents with computed height (if any) to disable scrolling and forbid displaying overflow content;
  • Specify overflow: auto to the element to enable scrolling inside it.

JSFiddle (element has direct parents with computed height)

JSFiddle (simple case: no direct parents with computed height)

Python NLTK: SyntaxError: Non-ASCII character '\xc3' in file (Sentiment Analysis -NLP)

Add the following to the top of your file # coding=utf-8

If you go to the link in the error you can seen the reason why:

Defining the Encoding

Python will default to ASCII as standard encoding if no other encoding hints are given. To define a source code encoding, a magic comment must be placed into the source files either as first or second line in the file, such as: # coding=

Datagridview full row selection but get single cell value

I just want to point out, you can use .selectedindex to make it a little cleaner

string value = gridview.Rows[gridview.SelectedIndex].Cells[1].Text.ToString();

equivalent of vbCrLf in c#

try this:

AccountList.Split(new String[]{"\r\n"},System.StringSplitOptions.None);

or

AccountList.Split(new String[]{"\r\n"},System.StringSplitOptions.RemoveEmptyEntries);

How do I get an object's unqualified (short) class name?

Quoting php.net:

On Windows, both slash (/) and backslash () are used as directory separator character. In other environments, it is the forward slash (/).

Based on this info and expanding from arzzzen answer this should work on both Windows and Nix* systems:

<?php

if (basename(str_replace('\\', '/', get_class($object))) == 'Name') {
    // ... do this ...
}

Note: I did a benchmark of ReflectionClass against basename+str_replace+get_class and using reflection is roughly 20% faster than using the basename approach, but YMMV.

Adding extra zeros in front of a number using jQuery?

This is the function that I generally use in my code to prepend zeros to a number or string.

The inputs are the string or number (str), and the desired length of the output (len).

var PrependZeros = function (str, len) {
    if(typeof str === 'number' || Number(str)){
    str = str.toString();
    return (len - str.length > 0) ? new Array(len + 1 - str.length).join('0') + str: str;
}
else{
    for(var i = 0,spl = str.split(' '); i < spl.length; spl[i] = (Number(spl[i])&& spl[i].length < len)?PrependZeros(spl[i],len):spl[i],str = (i == spl.length -1)?spl.join(' '):str,i++);
    return str;
}

};

Examples:

PrependZeros('MR 3',3);    // MR 003
PrependZeros('MR 23',3);   // MR 023
PrependZeros('MR 123',3);  // MR 123
PrependZeros('foo bar 23',3);  // foo bar 023

How to update Ruby with Homebrew?

To upgrade Ruby with rbenv: Per the rbenv README

  • Update first: brew upgrade rbenv ruby-build
  • See list of Ruby versions: versions available: rbenv install -l
  • Install: rbenv install <selected version>

Forcing anti-aliasing using css: Is this a myth?

I disagree with Chad Birch. We can force anti-aliasing, at least in Chrome using a simple css trick with the -webkit-text-stroke property:-

-webkit-text-stroke: 1px transparent;

angular-cli where is webpack.config.js file - new angular6 does not support ng eject

The CLI's webpack config can now be ejected. Check Anton Nikiforov's answer.


outdated:

You can hack the config template in angular-cli/addon/ng2/models. There's no official way to modify the webpack config as of now.

There's a closed "wont-fix" issue on github about this: https://github.com/angular/angular-cli/issues/1656

Get current value when change select option - Angular2

For me, passing ($event.target.value) as suggested by @microniks did not work. What worked was ($event.value) instead. I am using Angular 4.2.x and Angular Material 2

<select (change)="onItemChange($event.value)">
    <option *ngFor="#value of values" [value]="value.key">
       {{value.value}}
    </option>
</select>

Android Closing Activity Programmatically

you can use this.finish() if you want to close current activity.

this.finish()

Installing J2EE into existing eclipse IDE

You could install Web Tool Platform on top of your current installation to help you learn about Java EE. Download the Web Tools Platform by using Eclipse Software Update (Instruction at http://download.eclipse.org/webtools/updates/). It has features to get you going with learning Java EE. You could learn more about Web Tools Platform at http://www.eclipse.org/webtools/

compareTo() vs. equals()

The 2 main differences are that:

  1. equals will take any Object as a parameter, but compareTo will only take Strings.
  2. equals only tells you whether they're equal or not, but compareTo gives information on how the Strings compare lexicographically.

I took a look at the String class code, and the algorithm within compareTo and equals looks basically the same. I believe his opinion was just a matter of taste, and I agree with you -- if all you need to know is the equality of the Strings and not which one comes first lexicographically, then I would use equals.

How to draw a line in android

this code adds horizontal line to a linear layout

View view = new View(this);
LinearLayout.LayoutParams lpView = new LinearLayout.LayoutParams(LinearLayout.LayoutParams.MATCH_PARENT, 1); // --> horizontal
view.setLayoutParams(lpView);
view.setBackgroundColor(Color.DKGRAY);

linearLayout.addView(view);

How to get the GL library/headers?

Some of the answers above, in regards to linux, are either incomplete, or flat out wrong.

For example, /usr/include/GL/gl.h is not part of mesa-common-dev or has not been for many years.

At any rate, for a more current answer, these two packages are important:

https://mesa.freedesktop.org/archive/mesa-20.1.2.tar.xz

ftp://ftp.freedesktop.org/pub/mesa/glu/glu-9.0.1.tar.xz

The glu.h is part of glu itself:

GL/glu.h
GL/glu_mangle.h

Mesa is evidently significantly larger. Its headers are a bit variable, I suppose, depending on the flags given to meson, but should include these typically:

KHR/khrplatform.h                                                                                                         
EGL/eglplatform.h                                                                                                         
EGL/eglext.h                                                                                                              
EGL/eglextchromium.h                                                                                                      
EGL/eglmesaext.h                                                                                                          
EGL/egl.h                                                                                                                 
vulkan/vulkan_intel.h
gbm.h
GLES3/gl31.h
GLES3/gl3ext.h
GLES3/gl3.h
GLES3/gl32.h
GLES3/gl3platform.h
xa_composite.h
xa_tracker.h
xa_context.h
GLES2/gl2.h
GLES2/gl2platform.h
GLES2/gl2ext.h
GLES/gl.h
GLES/glplatform.h
GLES/glext.h
GLES/egl.h
GL/gl.h
GL/glx.h
GL/osmesa.h
GL/internal
GL/internal/dri_interface.h
GL/glcorearb.h
GL/glxext.h
GL/glext.h

Hope that helps anyone finding an answer this question in the future; compiling dosbox needs this, for instance, due to SDL opengl.

Change the "From:" address in Unix "mail"

It's also possible to set both the From name and from address using something like:

 echo test | mail -s "test" [email protected] -- -F'Some Name<[email protected]>' -t

For some reason passing -F'Some Name' and [email protected] doesn't work, but passing in the -t to sendmail works and is "easy".

Is there a way to represent a directory tree in a Github README.md?

You can also check this tree-extended package. It can be used as a command line app by using node >= 6.x.

It is very similar to tree but also has the option of configuring the max deep in the tree, that is one of the awful things of it. Also you can filter by using .gitignore file.

enter image description here

How can I transform string to UTF-8 in C#?

Use the below code snippet to get bytes from csv file

protected byte[] GetCSVFileContent(string fileName)
    {
        StringBuilder sb = new StringBuilder();
        using (StreamReader sr = new StreamReader(fileName, Encoding.Default, true))
        {
            String line;
            // Read and display lines from the file until the end of 
            // the file is reached.
            while ((line = sr.ReadLine()) != null)
            {
                sb.AppendLine(line);
            }
        }
        string allines = sb.ToString();


        UTF8Encoding utf8 = new UTF8Encoding();


        var preamble = utf8.GetPreamble();

        var data = utf8.GetBytes(allines);


        return data;
    }

Call the below and save it as an attachment

           Encoding csvEncoding = Encoding.UTF8;
                   //byte[] csvFile = GetCSVFileContent(FileUpload1.PostedFile.FileName);
          byte[] csvFile = GetCSVFileContent("Your_CSV_File_NAme");


        string attachment = String.Format("attachment; filename={0}.csv", "uomEncoded");

        Response.Clear();
        Response.ClearHeaders();
        Response.ClearContent();
        Response.ContentType = "text/csv";
        Response.ContentEncoding = csvEncoding;
        Response.AppendHeader("Content-Disposition", attachment);
        //Response.BinaryWrite(csvEncoding.GetPreamble());
        Response.BinaryWrite(csvFile);
        Response.Flush();
        Response.End();

Fetch API with Cookie

Have just solved. Just two f. days of brutforce

For me the secret was in following:

  1. I called POST /api/auth and see that cookies were successfully received.

  2. Then calling GET /api/users/ with credentials: 'include' and got 401 unauth, because of no cookies were sent with the request.

The KEY is to set credentials: 'include' for the first /api/auth call too.

python - checking odd/even numbers and changing outputs on number size

1) How do I check if it's even or odd? I tried "if number/2 == int" in the hope that it might do something, and the internet tells me to do "if number%2==0", but that doesn't work.

def isEven(number):
        return number % 2 == 0

Locate current file in IntelliJ

I am using IntelliJ IDEA 2016.2 Ultimate.

Alt+F1, then press 1

Completely remove MariaDB or MySQL from CentOS 7 or RHEL 7

These steps are working on CentOS 6.5 so they should work on CentOS 7 too:

(EDIT - exactly the same steps work for MariaDB 10.3 on CentOS 8)

  1. yum remove mariadb mariadb-server
  2. rm -rf /var/lib/mysql If your datadir in /etc/my.cnf points to a different directory, remove that directory instead of /var/lib/mysql
  3. rm /etc/my.cnf the file might have already been deleted at step 1
  4. Optional step: rm ~/.my.cnf
  5. yum install mariadb mariadb-server

[EDIT] - Update for MariaDB 10.1 on CentOS 7

The steps above worked for CentOS 6.5 and MariaDB 10.

I've just installed MariaDB 10.1 on CentOS 7 and some of the steps are slightly different.

Step 1 would become:

yum remove MariaDB-server MariaDB-client

Step 5 would become:

yum install MariaDB-server MariaDB-client

The other steps remain the same.

Convert HttpPostedFileBase to byte[]

As Darin says, you can read from the input stream - but I'd avoid relying on all the data being available in a single go. If you're using .NET 4 this is simple:

MemoryStream target = new MemoryStream();
model.File.InputStream.CopyTo(target);
byte[] data = target.ToArray();

It's easy enough to write the equivalent of CopyTo in .NET 3.5 if you want. The important part is that you read from HttpPostedFileBase.InputStream.

For efficient purposes you could check whether the stream returned is already a MemoryStream:

byte[] data;
using (Stream inputStream = model.File.InputStream)
{
    MemoryStream memoryStream = inputStream as MemoryStream;
    if (memoryStream == null)
    {
        memoryStream = new MemoryStream();
        inputStream.CopyTo(memoryStream);
    }
    data = memoryStream.ToArray();
}

Force flex item to span full row width

When you want a flex item to occupy an entire row, set it to width: 100% or flex-basis: 100%, and enable wrap on the container.

The item now consumes all available space. Siblings are forced on to other rows.

_x000D_
_x000D_
.parent {
  display: flex;
  flex-wrap: wrap;
}

#range, #text {
  flex: 1;
}

.error {
  flex: 0 0 100%; /* flex-grow, flex-shrink, flex-basis */
  border: 1px dashed black;
}
_x000D_
<div class="parent">
  <input type="range" id="range">
  <input type="text" id="text">
  <label class="error">Error message (takes full width)</label>
</div>
_x000D_
_x000D_
_x000D_

More info: The initial value of the flex-wrap property is nowrap, which means that all items will line up in a row. MDN

Return index of greatest value in an array

Unless I'm mistaken, I'd say it's to write your own function.

function findIndexOfGreatest(array) {
  var greatest;
  var indexOfGreatest;
  for (var i = 0; i < array.length; i++) {
    if (!greatest || array[i] > greatest) {
      greatest = array[i];
      indexOfGreatest = i;
    }
  }
  return indexOfGreatest;
}

Assign null to a SqlParameter

If you use the conditional(ternary) operator the compiler needs an implicit conversion between both types, otherwise you get an exception.

So you could fix it by casting one of both to System.Object:

planIndexParameter.Value = (AgeItem.AgeIndex== null) ? DBNull.Value : (object) AgeItem.AgeIndex;

But since the result is not really pretty and you always have to remember this casting, you could use such an extension method instead:

public static object GetDBNullOrValue<T>(this T val)
{
    bool isDbNull = true;
    Type t = typeof(T);

    if (Nullable.GetUnderlyingType(t) != null)
        isDbNull = EqualityComparer<T>.Default.Equals(default(T), val);
    else if (t.IsValueType)
        isDbNull = false;
    else
        isDbNull = val == null;

    return isDbNull ? DBNull.Value : (object) val;
}

Then you can use this concise code:

planIndexParameter.Value = AgeItem.AgeIndex.GetDBNullOrValue();

How to find the UpgradeCode and ProductCode of an installed application in Windows 7

If anyone wants to get installed application package code, just execute below command with your application name in the command prompt. You will be getting product code along with package code.

wmic product where "Name like '%YOUR_APPLICATION_NAME%'" get IdentifyingNumber, PackageCode

Text not wrapping inside a div element

This may help a small percentage of people still scratching their heads. Text copied from clipboard into VSCode may have an invisible hard space character preventing wrapping. Check it with HTML inspector

string with hard spaces

Jquery Change Height based on Browser Size/Resize

$(function(){
    $(window).resize(function(){
        var h = $(window).height();
        var w = $(window).width();
        $("#elementToResize").css('height',(h < 768 || w < 1024) ? 500 : 400);
    });
});

Scrollbars etc have an effect on the window size so you may want to tweak to desired size.

OpenCV - Saving images to a particular folder of choice

Answer given by Jeru Luke is working only on Windows systems, if we try on another operating system (Ubuntu) then it runs without error but the image is saved on target location or path.

Not working in Ubuntu and working in Windows

  import cv2
  img = cv2.imread('1.jpg', 1)
  path = '/tmp'
  cv2.imwrite(str(path) + 'waka.jpg',img)
  cv2.waitKey(0)

I run above code but the image does not save the image on target path. Then I found that the way of adding path is wrong for the general purpose we using OS module to add the path.

Example:

 import os
 final_path = os.path.join(path_1,path_2,path_3......)

working in Ubuntu and Windows

 import cv2
 import os
 img = cv2.imread('1.jpg', 1)
 path = 'D:/OpenCV/Scripts/Images'
 cv2.imwrite(os.path.join(path , 'waka.jpg'),img)
 cv2.waitKey(0)

that code works fine on both Windows and Ubuntu :)

When tracing out variables in the console, How to create a new line?

In ES6/ES2015 you can use string literal syntax called template literals. Template strings use backtick character instead of single quote ' or double quote marks ". They also preserve new line and tab

_x000D_
_x000D_
const roleName = 'test1';_x000D_
const role_ID = 'test2';_x000D_
const modal_ID = 'test3';_x000D_
const related = 'test4';_x000D_
        _x000D_
console.log(`_x000D_
  roleName = ${roleName}_x000D_
  role_ID = ${role_ID}_x000D_
  modal_ID = ${modal_ID}_x000D_
  related = ${related}_x000D_
`);
_x000D_
_x000D_
_x000D_

Remove a fixed prefix/suffix from a string in Bash

Using the =~ operator:

$ string="hello-world"
$ prefix="hell"
$ suffix="ld"
$ [[ "$string" =~ ^$prefix(.*)$suffix$ ]] && echo "${BASH_REMATCH[1]}"
o-wor

Align Div at bottom on main Div

Give your parent div position: relative, then give your child div position: absolute, this will absolute position the div inside of its parent, then you can give the child bottom: 0px;

See example here:

http://jsfiddle.net/PGMqs/1/

Stop and Start a service via batch or cmd file?

Syntax always gets me.... so...

Here is explicitly how to add a line to a batch file that will kill a remote service (on another machine) if you are an admin on both machines, run the .bat as an administrator, and the machines are on the same domain. The machine name follows the UNC format \myserver

sc \\ip.ip.ip.ip stop p4_1

In this case... p4_1 was both the Service Name and the Display Name, when you view the Properties for the service in Service Manager. You must use the Service Name.

For your Service Ops junkies... be sure to append your reason code and comment! i.e. '4' which equals 'Planned' and comment 'Stopping server for maintenance'

sc \\ip.ip.ip.ip stop p4_1 4 Stopping server for maintenance

Order of items in classes: Fields, Properties, Constructors, Methods

I don't know about a language or industry standard, but I tend to put things in this order with each section wrapped in a #region:

using Statements

Namespace

Class

Private members

Public properties

Constructors

Public methods

Private methods

How to clear a chart from a canvas so that hover events cannot be triggered?

This worked very well for me

    var ctx = $("#mycanvas");
     var LineGraph = new Chart(ctx, {
        type: 'line',
        data: chartdata});
        LineGraph.destroy();

Use .destroy this to destroy any chart instances that are created. This will clean up any references stored to the chart object within Chart.js, along with any associated event listeners attached by Chart.js. This must be called before the canvas is reused for a new chart.

Regex for password must contain at least eight characters, at least one number and both lower and uppercase letters and special characters

Just we can do this by using HTML5.

Use below code in pattern attribute,

pattern="(?=^.{8,}$)((?=.*\d)(?=.*\W+))(?![.\n])(?=.*[A-Z])(?=.*[a-z]).*$"

It will work perfectly.

How to return value from Action()?

You can use Func<T, TResult> generic delegate. (See MSDN)

Func<MyType, ReturnType> func = (db) => { return new MyType(); }

Also there are useful generic delegates which considers a return value:

  • Converter<TInput, TOutput> (MSDN)
  • Predicate<TInput> - always return bool (MSDN)

Method:

public MyType SimpleUsing.DoUsing<MyType>(Func<TInput, MyType> myTypeFactory)

Generic delegate:

Func<InputArgumentType, MyType> createInstance = db => return new MyType();

Execute:

MyType myTypeInstance = SimpleUsing.DoUsing(
                            createInstance(new InputArgumentType()));

OR explicitly:

MyType myTypeInstance = SimpleUsing.DoUsing(db => return new MyType());

The instance of entity type cannot be tracked because another instance of this type with the same key is already being tracked

I got this error from my background service. I solved which creating a new scope.

                using (var scope = serviceProvider.CreateScope())
                {
                      // Process
                }

Create an Array of Arraylists

I totally do not get it, why everyone is suggesting the genric type over the array particularly for this question.

What if my need is to index n different arraylists.

With declaring List<List<Integer>> I need to create n ArrayList<Integer> objects manually or put a for loop to create n lists or some other way, in any way it will always be my duty to create n lists.

Isn't it great if we declare it through casting as List<Integer>[] = (List<Integer>[]) new List<?>[somenumber]. I see it as a good design where one do not have to create all the indexing object (arraylists) by himself

Can anyone enlighten me why this (arrayform) will be a bad design and what are its disadvantages?

cartesian product in pandas

If you have no overlapping columns, don't want to add one, and the indices of the data frames can be discarded, this may be easier:

df1.index[:] = df2.index[:] = 0
df_cartesian = df1.join(df2, how='outer')
df_cartesian.index[:] = range(len(df_cartesian))

How to put a jar in classpath in Eclipse?

Right click your project in eclipse, build path -> add external jars.

Eclipse error: R cannot be resolved to a variable

In addition to install the build tools and restart the update manager I also had to restart Eclipse to make this work.

Programmatically go back to the previous fragment in the backstack

This solution works perfectly for bottom bar based fragment navigation when you want to close the app when back pressed in primary fragment.

On the other hand when you are opening the secondary fragment (fragment in fragment) which is defined as "DetailedPizza" in my code it will return the previous state of primary fragment. Cheers !

Inside activities on back pressed put this:

Fragment home = getSupportFragmentManager().findFragmentByTag("DetailedPizza");

if (home instanceof FragmentDetailedPizza && home.isVisible()) {
    if (getFragmentManager().getBackStackEntryCount() != 0) {
        getFragmentManager().popBackStack();
    } else {
        super.onBackPressed();
    }
} else {
    //Primary fragment
    moveTaskToBack(true);
}

And launch the other fragment like this:

Fragment someFragment = new FragmentDetailedPizza();
FragmentTransaction transaction = getFragmentManager().beginTransaction();
transaction.replace(R.id.container_body, someFragment, "DetailedPizza");
transaction.addToBackStack("DetailedPizza");
transaction.commit();

What are the differences between B trees and B+ trees?

Example from Database system concepts 5th

B+-tree B+tree

corresponding B-tree Btree

Number of elements in a javascript object

The concept of number/length/dimensionality doesn't really make sense for an Object, and needing it suggests you really want an Array to me.

Edit: Pointed out to me that you want an O(1) for this. To the best of my knowledge no such way exists I'm afraid.

jump to line X in nano editor

The shortcut is: CTRL+shift+- ("shift+-" results in "_") After typing the shortcut, nano will let you to enter the line you wanna jump to, type in the line number, then press ENTR.

How do I comment out a block of tags in XML?

Here for commenting we have to write like below:

<!-- Your comment here -->

Shortcuts for IntelliJ Idea and Eclipse

For Windows & Linux:

Shortcut for Commenting a single line:

Ctrl + /

Shortcut for Commenting multiple lines:

Ctrl + Shift + /

For Mac:

Shortcut for Commenting a single line:

cmnd + /

Shortcut for Commenting multiple lines:

cmnd + Shift + /

One thing you have to keep in mind that, you can't comment an attribute of an XML tag. For Example:

<TextView
    android:layout_width="match_parent"
    android:layout_height="wrap_content"
    <!--android:text="Hello.."-->
    android:textStyle="bold" />

Here, TextView is a XML Tag and text is an attribute of that tag. You can't comment attributes of an XML Tag. You have to comment the full XML Tag. For Example:

<!--<TextView
    android:layout_width="match_parent"
    android:layout_height="wrap_content"
    android:text="Hello.."
    android:textStyle="bold" />-->

Codesign error: Provisioning profile cannot be found after deleting expired profile

I was having issues because I updated my AdHoc provisioning profile with some new devices for use on TestFlight. Assumedly this is happening because Xcode has an old reference to your provisioning profile in either the codesigning build settings for the project or the targets. The way I fixed mine was to:

  1. Go to both target build settings and project build settings, Under code signing change all the provisioning profiles to something else.
  2. Go to devices/provisioning profiles in the Organizer delete the offending profiles, then click the refresh button in the bottom right.
  3. Go back to to the target and project build settings and set your provisioning profiles to the appropriate (hopefully) newly refreshed provisioning profiles.

How to convert UTF-8 byte[] to string?

string result = System.Text.Encoding.UTF8.GetString(byteArray);

How to check if an element exists in the xml using xpath?

Use the boolean() XPath function

The boolean function converts its argument to a boolean as follows:

  • a number is true if and only if it is neither positive or negative zero nor NaN

  • a node-set is true if and only if it is non-empty

  • a string is true if and only if its length is non-zero

  • an object of a type other than the four basic types is converted to a boolean in a way that is dependent on that type

If there is an AttachedXml in the CreditReport of primary Consumer, then it will return true().

boolean(/mc:Consumers
          /mc:Consumer[@subjectIdentifier='Primary']
            //mc:CreditReport/mc:AttachedXml)

foreach for JSON array , syntax

You can do something like

for(var k in result) {
   console.log(k, result[k]);
}

which loops over all the keys in the returned json and prints the values. However, if you have a nested structure, you will need to use

typeof result[k] === "object"

to determine if you have to loop over the nested objects. Most APIs I have used, the developers know the structure of what is being returned, so this is unnecessary. However, I suppose it's possible that this expectation is not good for all cases.

What does EntityManager.flush do and why do I need to use it?

So when you call EntityManager.persist(), it only makes the entity get managed by the EntityManager and adds it (entity instance) to the Persistence Context. An Explicit flush() will make the entity now residing in the Persistence Context to be moved to the database (using a SQL).

Without flush(), this (moving of entity from Persistence Context to the database) will happen when the Transaction to which this Persistence Context is associated is committed.

Play audio from a stream using C#

I haven't tried it from a WebRequest, but both the Windows Media Player ActiveX and the MediaElement (from WPF) components are capable of playing and buffering MP3 streams.

I use it to play data coming from a SHOUTcast stream and it worked great. However, I'm not sure if it will work in the scenario you propose.

How do I reference tables in Excel using VBA?

In addition, it's convenient to define variables referring to objects. For instance,

Sub CreateTable()
    Dim lo as ListObject
    Set lo = ActiveSheet.ListObjects.Add(xlSrcRange, Range("$B$1:$D$16"), , xlYes)
    lo.Name = "Table1"
    lo.TableStyle = "TableStyleLight2"
    ...
End Sub

You will probably find it advantageous at once.

CSS: center element within a <div> element

If you want to use CSS3:

position:absolute;
left:calc(50% - PutTheSizeOfTheHalfOfYourElementpx);

You might want to do further searches to figure out how to get the percentage to fit your element's width.

Why doesn't Git ignore my specified file?

Please use this command

git rm -rf --cached .
git add .

Sometimes .gitignore files don't work even though they're correct. The reason Git ignores files is that they are not added to the repository. If you added a file that you want to ignore before, it will be tracked by Git, and any skipping matching rules will be skipped. Git does this because the file is already part of the repository.

Unable to find a @SpringBootConfiguration when doing a JpaTest

The test slice provided in Spring Boot 1.4 brought feature oriented test capabilities.

For example,

@JsonTest provides a simple Jackson environment to test the json serialization and deserialization.

@WebMvcTest provides a mock web environment, it can specify the controller class for test and inject the MockMvc in the test.

@WebMvcTest(PostController.class)
public class PostControllerMvcTest{

    @Inject MockMvc mockMvc;

}

@DataJpaTest will prepare an embedded database and provides basic JPA environment for the test.

@RestClientTest provides REST client environment for the test, esp the RestTemplateBuilder etc.

These annotations are not composed with SpringBootTest, they are combined with a series of AutoconfigureXXX and a @TypeExcludesFilter annotations.

Have a look at @DataJpaTest.

@Target(ElementType.TYPE)
@Retention(RetentionPolicy.RUNTIME)
@Documented
@Inherited
@BootstrapWith(SpringBootTestContextBootstrapper.class)
@OverrideAutoConfiguration(enabled = false)
@TypeExcludeFilters(DataJpaTypeExcludeFilter.class)
@Transactional
@AutoConfigureCache
@AutoConfigureDataJpa
@AutoConfigureTestDatabase
@AutoConfigureTestEntityManager
@ImportAutoConfiguration
public @interface DataJpaTest {}

You can add your @AutoconfigureXXX annotation to override the default config.

@AutoConfigureTestDatabase(replace=NONE)
@DataJpaTest
public class TestClass{
}

Let's have a look at your problem,

  1. Do not mix @DataJpaTest and @SpringBootTest, as said above @DataJpaTest will build the configuration in its own way(eg. by default, it will try to prepare an embedded H2 instead) from the application configuration inheritance. @DataJpaTest is designated for test slice.
  2. If you want to customize the configuration of @DataJpaTest, please read this official blog entry from Spring.io for this topic,(a little tedious).
  3. Split the configurations in Application into smaller configurations by features, such as WebConfig, DataJpaConfig etc. A full featured configuration(mixed web, data, security etc) also caused your test slice based tests to be failed. Check the test samples in my sample.

jQuery: get parent tr for selected radio button

Try this.

You don't need to prefix attribute name by @ in jQuery selector. Use closest() method to get the closest parent element matching the selector.

$("#MwDataList input[name=selectRadioGroup]:checked").closest('tr');

You can simplify your method like this

function getSelectedRowGuid() {
    return GetRowGuid(
      $("#MwDataList > input:radio[@name=selectRadioGroup]:checked :parent tr"));
}

closest() - Gets the first element that matches the selector, beginning at the current element and progressing up through the DOM tree.

As a side note, the ids of the elements should be unique on the page so try to avoid having same ids for radio buttons which I can see in your markup. If you are not going to use the ids then just remove it from the markup.

What are the most common font-sizes for H1-H6 tags

Headings are normally bold-faced; that has been turned off for this demonstration of size correspondence. MSIE and Opera interpret these sizes the same, but note that Gecko browsers and Chrome interpret Heading 6 as 11 pixels instead of 10 pixels/font size 1, and Heading 3 as 19 pixels instead of 18 pixels/font size 4 (though it's difficult to tell the difference even in a direct comparison and impossible in use). It seems Gecko also limits text to no smaller than 10 pixels.

How to convert .pfx file to keystore with private key?

I found this page which tells you how to import a PFX to JKS (Java Key Store):

keytool -importkeystore -srckeystore PFX_P12_FILE_NAME -srcstoretype pkcs12 -srcstorepass PFX_P12_FILE -srcalias SOURCE_ALIAS -destkeystore KEYSTORE_FILE -deststoretype jks -deststorepass PASSWORD -destalias ALIAS_NAME

How do I install boto?

While trying out the

pip install boto

command, I encounter the error

ImportError: No module named pkg_resources

To resolve this, issue another command to handle the setuptools using curl

curl https://bootstrap.pypa.io/ez_setup.py | python

After doing that, the following command will work perfectly.

pip install boto

How to implement linear interpolation?

import scipy.interpolate
y_interp = scipy.interpolate.interp1d(x, y)
print y_interp(5.0)

scipy.interpolate.interp1d does linear interpolation by and can be customized to handle error conditions.

Proper MIME type for OTF fonts

Ignore the chrome warning. There is no standard MIME type for OTF fonts.

font/opentype may silence the warning, but that doesn't make it the "right" thing to do.

Arguably, you're better off making one up, e.g. with "application/x-opentype" because at least "application" is a registered content type, while "font" is not.

Update: OTF remains a problem, but WOFF grew an IANA MIME type of application/font-woff in January 2013.

Update 2: OTF has grown a MIME type: application/font-sfnt In March 2013. This type also applies to .ttf

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

Make

if [ "$file" == "*.txt" ]

like this:

if [[ $file == *.txt ]]

That is, double brackets and no quotes.

The right side of == is a shell pattern. If you need a regular expression, use =~ then.

SQL query return data from multiple tables

Ok, I found this post very interesting and I would like to share some of my knowledge on creating a query. Thanks for this Fluffeh. Others who may read this and may feel that I'm wrong are 101% free to edit and criticise my answer. (Honestly, I feel very thankful for correcting my mistake(s).)

I'll be posting some of the frequently asked questions in MySQL tag.


Trick No. 1 (rows that matches to multiple conditions)

Given this schema

CREATE TABLE MovieList
(
    ID INT,
    MovieName VARCHAR(25),
    CONSTRAINT ml_pk PRIMARY KEY (ID),
    CONSTRAINT ml_uq UNIQUE (MovieName)
);

INSERT INTO MovieList VALUES (1, 'American Pie');
INSERT INTO MovieList VALUES (2, 'The Notebook');
INSERT INTO MovieList VALUES (3, 'Discovery Channel: Africa');
INSERT INTO MovieList VALUES (4, 'Mr. Bean');
INSERT INTO MovieList VALUES (5, 'Expendables 2');

CREATE TABLE CategoryList
(
    MovieID INT,
    CategoryName VARCHAR(25),
    CONSTRAINT cl_uq UNIQUE(MovieID, CategoryName),
    CONSTRAINT cl_fk FOREIGN KEY (MovieID) REFERENCES MovieList(ID)
);

INSERT INTO CategoryList VALUES (1, 'Comedy');
INSERT INTO CategoryList VALUES (1, 'Romance');
INSERT INTO CategoryList VALUES (2, 'Romance');
INSERT INTO CategoryList VALUES (2, 'Drama');
INSERT INTO CategoryList VALUES (3, 'Documentary');
INSERT INTO CategoryList VALUES (4, 'Comedy');
INSERT INTO CategoryList VALUES (5, 'Comedy');
INSERT INTO CategoryList VALUES (5, 'Action');

QUESTION

Find all movies that belong to at least both Comedy and Romance categories.

Solution

This question can be very tricky sometimes. It may seem that a query like this will be the answer:-

SELECT  DISTINCT a.MovieName
FROM    MovieList a
        INNER JOIN CategoryList b
            ON a.ID = b.MovieID
WHERE   b.CategoryName = 'Comedy' AND
        b.CategoryName = 'Romance'

SQLFiddle Demo

which is definitely very wrong because it produces no result. The explanation of this is that there is only one valid value of CategoryName on each row. For instance, the first condition returns true, the second condition is always false. Thus, by using AND operator, both condition should be true; otherwise, it will be false. Another query is like this,

SELECT  DISTINCT a.MovieName
FROM    MovieList a
        INNER JOIN CategoryList b
            ON a.ID = b.MovieID
WHERE   b.CategoryName IN ('Comedy','Romance')

SQLFiddle Demo

and the result is still incorrect because it matches to record that has at least one match on the categoryName. The real solution would be by counting the number of record instances per movie. The number of instance should match to the total number of the values supplied in the condition.

SELECT  a.MovieName
FROM    MovieList a
        INNER JOIN CategoryList b
            ON a.ID = b.MovieID
WHERE   b.CategoryName IN ('Comedy','Romance')
GROUP BY a.MovieName
HAVING COUNT(*) = 2

SQLFiddle Demo (the answer)


Trick No. 2 (maximum record for each entry)

Given schema,

CREATE TABLE Software
(
    ID INT,
    SoftwareName VARCHAR(25),
    Descriptions VARCHAR(150),
    CONSTRAINT sw_pk PRIMARY KEY (ID),
    CONSTRAINT sw_uq UNIQUE (SoftwareName)  
);

INSERT INTO Software VALUES (1,'PaintMe','used for photo editing');
INSERT INTO Software VALUES (2,'World Map','contains map of different places of the world');
INSERT INTO Software VALUES (3,'Dictionary','contains description, synonym, antonym of the words');

CREATE TABLE VersionList
(
    SoftwareID INT,
    VersionNo INT,
    DateReleased DATE,
    CONSTRAINT sw_uq UNIQUE (SoftwareID, VersionNo),
    CONSTRAINT sw_fk FOREIGN KEY (SOftwareID) REFERENCES Software(ID)
);

INSERT INTO VersionList VALUES (3, 2, '2009-12-01');
INSERT INTO VersionList VALUES (3, 1, '2009-11-01');
INSERT INTO VersionList VALUES (3, 3, '2010-01-01');
INSERT INTO VersionList VALUES (2, 2, '2010-12-01');
INSERT INTO VersionList VALUES (2, 1, '2009-12-01');
INSERT INTO VersionList VALUES (1, 3, '2011-12-01');
INSERT INTO VersionList VALUES (1, 2, '2010-12-01');
INSERT INTO VersionList VALUES (1, 1, '2009-12-01');
INSERT INTO VersionList VALUES (1, 4, '2012-12-01');

QUESTION

Find the latest version on each software. Display the following columns: SoftwareName,Descriptions,LatestVersion (from VersionNo column),DateReleased

Solution

Some SQL developers mistakenly use MAX() aggregate function. They tend to create like this,

SELECT  a.SoftwareName, a.Descriptions,
        MAX(b.VersionNo) AS LatestVersion, b.DateReleased
FROM    Software a
        INNER JOIN VersionList b
            ON a.ID = b.SoftwareID
GROUP BY a.ID
ORDER BY a.ID

SQLFiddle Demo

(most RDBMS generates a syntax error on this because of not specifying some of the non-aggregated columns on the group by clause) the result produces the correct LatestVersion on each software but obviously the DateReleased are incorrect. MySQL doesn't support Window Functions and Common Table Expression yet as some RDBMS do already. The workaround on this problem is to create a subquery which gets the individual maximum versionNo on each software and later on be joined on the other tables.

SELECT  a.SoftwareName, a.Descriptions,
        b.LatestVersion, c.DateReleased
FROM    Software a
        INNER JOIN
        (
            SELECT  SoftwareID, MAX(VersionNO) LatestVersion
            FROM    VersionList
            GROUP BY SoftwareID
        ) b ON a.ID = b.SoftwareID
        INNER JOIN VersionList c
            ON  c.SoftwareID = b.SoftwareID AND
                c.VersionNO = b.LatestVersion
GROUP BY a.ID
ORDER BY a.ID

SQLFiddle Demo (the answer)


So that was it. I'll be posting another soon as I recall any other FAQ on MySQL tag. Thank you for reading this little article. I hope that you have atleast get even a little knowledge from this.

UPDATE 1


Trick No. 3 (Finding the latest record between two IDs)

Given Schema

CREATE TABLE userList
(
    ID INT,
    NAME VARCHAR(20),
    CONSTRAINT us_pk PRIMARY KEY (ID),
    CONSTRAINT us_uq UNIQUE (NAME)  
);

INSERT INTO userList VALUES (1, 'Fluffeh');
INSERT INTO userList VALUES (2, 'John Woo');
INSERT INTO userList VALUES (3, 'hims056');

CREATE TABLE CONVERSATION
(
    ID INT,
    FROM_ID INT,
    TO_ID INT,
    MESSAGE VARCHAR(250),
    DeliveryDate DATE
);

INSERT INTO CONVERSATION VALUES (1, 1, 2, 'hi john', '2012-01-01');
INSERT INTO CONVERSATION VALUES (2, 2, 1, 'hello fluff', '2012-01-02');
INSERT INTO CONVERSATION VALUES (3, 1, 3, 'hey hims', '2012-01-03');
INSERT INTO CONVERSATION VALUES (4, 1, 3, 'please reply', '2012-01-04');
INSERT INTO CONVERSATION VALUES (5, 3, 1, 'how are you?', '2012-01-05');
INSERT INTO CONVERSATION VALUES (6, 3, 2, 'sample message!', '2012-01-05');

QUESTION

Find the latest conversation between two users.

Solution

SELECT    b.Name SenderName,
          c.Name RecipientName,
          a.Message,
          a.DeliveryDate
FROM      Conversation a
          INNER JOIN userList b
            ON a.From_ID = b.ID
          INNER JOIN userList c
            ON a.To_ID = c.ID
WHERE     (LEAST(a.FROM_ID, a.TO_ID), GREATEST(a.FROM_ID, a.TO_ID), DeliveryDate)
IN
(
    SELECT  LEAST(FROM_ID, TO_ID) minFROM,
            GREATEST(FROM_ID, TO_ID) maxTo,
            MAX(DeliveryDate) maxDate
    FROM    Conversation
    GROUP BY minFROM, maxTo
)

SQLFiddle Demo

jQuery count child elements

fastest one:

$("div#selected ul li").length

"No X11 DISPLAY variable" - what does it mean?

Very Easy, Had this same problem then what i did was to download and install an app that would help in displaying then fixed the error.

Download this app xming:

http://sourceforge.net/project/downloading.php?

Install, then use settings on this link:

http://www.geo.mtu.edu/geoschem/docs/putty_install.html or follow this steps:

Installing/Configuring PuTTy and Xming

Once PuTTy and Xming have been downloaded to the PC, install according to their respective instructions.

Configuring Xming

Once Xming is installed, run the application called 'XLaunch' and verify that the settings are as shown:

  • select Default entries on Display Settings windows, click next
  • click next on Session Type window.
  • click next on Additional parameters window(Notice clipboard checkbox is true)
  • save configuration and click to finish.

Configuring PuTTy

After installing PuTTy, double-click on the PuTTy icon on the desktop and configure as shown:

This shows creating a login profile then saving it.

  • On ssh -> X11, click on checkbox to enable X11 forwarding.
  • on X display location textbox, type localhost:0.0

save profile then connect remotely to server to test.

Cheers!!!

Retrieving a Foreign Key value with django-rest-framework serializers

Just use a related field without setting many=True.

Note that also because you want the output named category_name, but the actual field is category, you need to use the source argument on the serializer field.

The following should give you the output you need...

class ItemSerializer(serializers.ModelSerializer):
    category_name = serializers.RelatedField(source='category', read_only=True)

    class Meta:
        model = Item
        fields = ('id', 'name', 'category_name')

What is a Data Transfer Object (DTO)?

In general Value Objects should be Immutable. Like Integer or String objects in Java. We can use them for transferring data between software layers. If the software layers or services running in different remote nodes like in a microservices environment or in a legacy Java Enterprise App. We must make almost exact copies of two classes. This is the where we met DTOs.

|-----------|                                                   |--------------|
| SERVICE 1 |--> Credentials DTO >--------> Credentials DTO >-- | AUTH SERVICE |
|-----------|                                                   |--------------|

In legacy Java Enterprise Systems DTOs can have various EJB stuff in it.

I do not know this is a best practice or not but I personally use Value Objects in my Spring MVC/Boot Projects like this:

        |------------|         |------------------|                             |------------|
-> Form |            | -> Form |                  | -> Entity                   |            |
        | Controller |         | Service / Facade |                             | Repository |
<- View |            | <- View |                  | <- Entity / Projection View |            |
        |------------|         |------------------|                             |------------|

Controller layer doesn't know what are the entities are. It communicates with Form and View Value Objects. Form Objects has JSR 303 Validation annotations (for instance @NotNull) and View Value Objects have Jackson Annotations for custom serialization. (for instance @JsonIgnore)

Service layer communicates with repository layer via using Entity Objects. Entity objects have JPA/Hibernate/Spring Data annotations on it. Every layer communicates with only the lower layer. The inter-layer communication is prohibited because of circular/cyclic dependency.

User Service ----> XX CANNOT CALL XX ----> Order Service

Some ORM Frameworks have the ability of projection via using additional interfaces or classes. So repositories can return View objects directly. There for you do not need an additional transformation.

For instance this is our User entity:

@Entity
public final class User {
    private String id;
    private String firstname;
    private String lastname;
    private String phone;
    private String fax;
    private String address;
    // Accessors ...
}

But you should return a Paginated list of users that just include id, firstname, lastname. Then you can create a View Value Object for ORM projection.

public final class UserListItemView {
    private String id;
    private String firstname;
    private String lastname;
    // Accessors ...
}

You can easily get the paginated result from repository layer. Thanks to spring you can also use just interfaces for projections.

List<UserListItemView> find(Pageable pageable);

Don't worry for other conversion operations BeanUtils.copy method works just fine.

Does Eclipse have line-wrap

From Bug 35779 - Comment 187:

A workaround, that I use for the last years now, is to use the eclipse wiki markup editor for editing text files. This supports word wrap, and this is enough for me. Maybe this information could be of help to some of you.

How to write inside a DIV box with javascript

I would suggest Jquery:

$("#log").html("Type what you want to be shown to the user");   

How do I find my host and username on mysql?

You should be able to access the local database by using the name localhost. There is also a way to determine the hostname of the computer you're running on, but it doesn't sound like you need that. As for the username, you can either (1) give permissions to the account that PHP runs under to access the database without a password, or (2) store the username and password that you need to connect with (hard-coded or stored in a config file), and pass those as arguments to mysql_connect. See http://php.net/manual/en/function.mysql-connect.php.

How to change the background colour's opacity in CSS

Use RGBA like this: background-color: rgba(255, 0, 0, .5)

Select multiple columns using Entity Framework

Here is a code sample:

var dataset = entities.processlists
    .Where(x => x.environmentID == environmentid && x.ProcessName == processname && x.RemoteIP == remoteip && x.CommandLine == commandlinepart)
    .Select(x => new PInfo 
                 { 
                      ServerName = x.ServerName, 
                      ProcessID = x.ProcessID, 
                      UserName = x.Username 
                 }) AsEnumerable().
               Select(y => new PInfo
               {
                   ServerName = y.ServerName,
                   ProcessID = y.ProcessID,
                   UserName = y.UserName 
               }).ToList();

Get ID of element that called a function

Pass a reference to the element into the function when it is called:

<area id="nose" onmouseover="zoom(this);" />

<script>
  function zoom(ele) {
    var id = ele.id;

    console.log('area element id = ' + id);
  }
</script>

Using putty to scp from windows to Linux

You can use PSCP to copy files from Windows to Linux.

  1. Download PSCP from putty.org
  2. Open cmd in the directory with pscp.exe file
  3. Type command pscp source_file user@host:destination_file

Reference

git still shows files as modified after adding to .gitignore

Using git rm --cached *file* is not working fine for me (I'm aware this question is 8 years old, but it still shows at the top of the search for this topic), it does remove the file from the index, but it also deletes the file from the remote.

I have no idea why that is. All I wanted was keeping my local config isolated (otherwise I had to comment the localhost base url before every commit), not delete the remote equivalent to config.

Reading some more I found what seems to be the proper way to do this, and the only way that did what I needed, although it does require more attention, especially during merges.

Anyway, all it requires is git update-index --assume-unchanged *path/to/file*.

As far as I understand, this is the most notable thing to keep in mind:

Git will fail (gracefully) in case it needs to modify this file in the index e.g. when merging in a commit; thus, in case the assumed-untracked file is changed upstream, you will need to handle the situation manually.

Combine two columns of text in pandas dataframe

Let us suppose your dataframe is df with columns Year and Quarter.

import pandas as pd
df = pd.DataFrame({'Quarter':'q1 q2 q3 q4'.split(), 'Year':'2000'})

Suppose we want to see the dataframe;

df
>>>  Quarter    Year
   0    q1      2000
   1    q2      2000
   2    q3      2000
   3    q4      2000

Finally, concatenate the Year and the Quarter as follows.

df['Period'] = df['Year'] + ' ' + df['Quarter']

You can now print df to see the resulting dataframe.

df
>>>  Quarter    Year    Period
    0   q1      2000    2000 q1
    1   q2      2000    2000 q2
    2   q3      2000    2000 q3
    3   q4      2000    2000 q4

If you do not want the space between the year and quarter, simply remove it by doing;

df['Period'] = df['Year'] + df['Quarter']

comparing two strings in SQL Server

There is no direct string compare function in SQL Server

CASE
  WHEN str1 = str2 THEN 0
  WHEN str1 < str2 THEN -1
  WHEN str1 > str2 THEN 1
  ELSE NULL --one of the strings is NULL so won't compare (added on edit)
END

Notes

  • you can wraps this via a UDF using CREATE FUNCTION etc
  • you may need NULL handling (in my code above, any NULL will report 1)
  • str1 and str2 will be column names or @variables

Oracle date to string conversion

The data in COL1 is in dd-mon-yy

No it's not. A DATE column does not have any format. It is only converted (implicitely) to that representation by your SQL client when you display it.

If COL1 is really a DATE column using to_date() on it is useless because to_date() converts a string to a DATE.

You only need to_char(), nothing else:

SELECT TO_CHAR(col1, 'mm/dd/yyyy') 
FROM TABLE1

What happens in your case is that calling to_date() converts the DATE into a character value (applying the default NLS format) and then converting that back to a DATE. Due to this double implicit conversion some information is lost on the way.


Edit

So you did make that big mistake to store a DATE in a character column. And that's why you get the problems now.

The best (and to be honest: only sensible) solution is to convert that column to a DATE. Then you can convert the values to any rerpresentation that you want without worrying about implicit data type conversion.

But most probably the answer is "I inherited this model, I have to cope with it" (it always is, apparently no one ever is responsible for choosing the wrong datatype), then you need to use RR instead of YY:

SELECT TO_CHAR(TO_DATE(COL1,'dd-mm-rr'), 'mm/dd/yyyy')
FROM TABLE1

should do the trick. Note that I also changed mon to mm as your example is 27-11-89 which has a number for the month, not an "word" (like NOV)

For more details see the manual: http://docs.oracle.com/cd/B28359_01/server.111/b28286/sql_elements004.htm#SQLRF00215

Why cannot cast Integer to String in java?

No, Integer and String are different types. To convert an integer to string use: String.valueOf(integer), or Integer.toString(integer) for primitive, or Integer.toString() for the object.

how to get current month and year

If you have following two labels:

<asp:Label ID="MonthLabel" runat="server" />
<asp:Label ID="YearLabel" runat="server" />

Than you can use following code just need to set the Text Property for these labels like:

MonthLabel.Text = DateTime.Now.Month.ToString();
YearLabel.Text = DateTime.Now.Year.ToString();

Xcode 6: Keyboard does not show up in simulator

To enable/disable simulator keyboard: click ?+?+K to show the keyboard on simulator, click again to disable (hide) the keyboard.

Implement specialization in ER diagram

So I assume your permissions table has a foreign key reference to admin_accounts table. If so because of referential integrity you will only be able to add permissions for account ids exsiting in the admin accounts table. Which also means that you wont be able to enter a user_account_id [assuming there are no duplicates!]

Dynamic tabs with user-click chosen components

I'm not cool enough for comments. I fixed the plunker from the accepted answer to work for rc2. Nothing fancy, links to the CDN were just broken is all.

'@angular/core': {
  main: 'bundles/core.umd.js',
  defaultExtension: 'js'
},
'@angular/compiler': {
  main: 'bundles/compiler.umd.js',
  defaultExtension: 'js'
},
'@angular/common': {
  main: 'bundles/common.umd.js',
  defaultExtension: 'js'
},
'@angular/platform-browser-dynamic': {
  main: 'bundles/platform-browser-dynamic.umd.js',
  defaultExtension: 'js'
},
'@angular/platform-browser': {
  main: 'bundles/platform-browser.umd.js',
  defaultExtension: 'js'
},

https://plnkr.co/edit/kVJvI1vkzrLZJeRFsZuv?p=preview

NodeJS: How to decode base64 encoded string back to binary?

As of Node.js v6.0.0 using the constructor method has been deprecated and the following method should instead be used to construct a new buffer from a base64 encoded string:

var b64string = /* whatever */;
var buf = Buffer.from(b64string, 'base64'); // Ta-da

For Node.js v5.11.1 and below

Construct a new Buffer and pass 'base64' as the second argument:

var b64string = /* whatever */;
var buf = new Buffer(b64string, 'base64'); // Ta-da

If you want to be clean, you can check whether from exists :

if (typeof Buffer.from === "function") {
    // Node 5.10+
    buf = Buffer.from(b64string, 'base64'); // Ta-da
} else {
    // older Node versions, now deprecated
    buf = new Buffer(b64string, 'base64'); // Ta-da
}

How do I sort a two-dimensional (rectangular) array in C#?

Can I check - do you mean a rectangular array ([,])or a jagged array ([][])?

It is quite easy to sort a jagged array; I have a discussion on that here. Obviously in this case the Comparison<T> would involve a column instead of sorting by ordinal - but very similar.

Sorting a rectangular array is trickier... I'd probably be tempted to copy the data out into either a rectangular array or a List<T[]>, and sort there, then copy back.

Here's an example using a jagged array:

static void Main()
{  // could just as easily be string...
    int[][] data = new int[][] { 
        new int[] {1,2,3}, 
        new int[] {2,3,4}, 
        new int[] {2,4,1} 
    }; 
    Sort<int>(data, 2); 
} 
private static void Sort<T>(T[][] data, int col) 
{ 
    Comparer<T> comparer = Comparer<T>.Default;
    Array.Sort<T[]>(data, (x,y) => comparer.Compare(x[col],y[col])); 
} 

For working with a rectangular array... well, here is some code to swap between the two on the fly...

static T[][] ToJagged<T>(this T[,] array) {
    int height = array.GetLength(0), width = array.GetLength(1);
    T[][] jagged = new T[height][];

    for (int i = 0; i < height; i++)
    {
        T[] row = new T[width];
        for (int j = 0; j < width; j++)
        {
            row[j] = array[i, j];
        }
        jagged[i] = row;
    }
    return jagged;
}
static T[,] ToRectangular<T>(this T[][] array)
{
    int height = array.Length, width = array[0].Length;
    T[,] rect = new T[height, width];
    for (int i = 0; i < height; i++)
    {
        T[] row = array[i];
        for (int j = 0; j < width; j++)
        {
            rect[i, j] = row[j];
        }
    }
    return rect;
}
// fill an existing rectangular array from a jagged array
static void WriteRows<T>(this T[,] array, params T[][] rows)
{
    for (int i = 0; i < rows.Length; i++)
    {
        T[] row = rows[i];
        for (int j = 0; j < row.Length; j++)
        {
            array[i, j] = row[j];
        }
    }
}

Setting environment variables on OS X

The $PATH variable is also subject to path_helper, which in turn makes use of the /etc/paths file and files in /etc/paths.d.

A more thorough description can be found in PATH and other environment issues in Leopard (2008-11)

Android Facebook 4.0 SDK How to get Email, Date of Birth and gender of User

You won't get Profile in onSuccess() you need to implement ProfileTracker along with registering callback

mProfileTracker = new ProfileTracker() {
    @Override
    protected void onCurrentProfileChanged(Profile oldProfile, Profile newProfile) {
        // Fetch user details from New Profile
    }
};

Also don't forget to handle the start and stop of profile tracker

Now you will have a profile to get AccessToken from (solved the issue of null profile). You just have to use "https://developers.facebook.com/docs/android/graph#userdata" to get any data.

How can I test that a variable is more than eight characters in PowerShell?

You can also use -match against a Regular expression. Ex:

if ($dbUserName -match ".{8}" )
{
    Write-Output " Please enter more than 8 characters "
    $dbUserName=read-host " Re-enter database user name"
}

Also if you're like me and like your curly braces to be in the same horizontal position for your code blocks, you can put that on a new line, since it's expecting a code block it will look on next line. In some commands where the first curly brace has to be in-line with your command, you can use a grave accent marker (`) to tell powershell to treat the next line as a continuation.

jQuery get mouse position within an element

This solution supports all major browsers including IE. It also takes care of scrolling. First, it retrieves the position of the element relative to the page efficiently, and without using a recursive function. Then it gets the x and y of the mouse click relative to the page and does the subtraction to get the answer which is the position relative to the element (the element can be an image or div for example):

function getXY(evt) {
    var element = document.getElementById('elementId');  //replace elementId with your element's Id.
    var rect = element.getBoundingClientRect();
    var scrollTop = document.documentElement.scrollTop?
                    document.documentElement.scrollTop:document.body.scrollTop;
    var scrollLeft = document.documentElement.scrollLeft?                   
                    document.documentElement.scrollLeft:document.body.scrollLeft;
    var elementLeft = rect.left+scrollLeft;  
    var elementTop = rect.top+scrollTop;

        if (document.all){ //detects using IE   
            x = event.clientX+scrollLeft-elementLeft; //event not evt because of IE
            y = event.clientY+scrollTop-elementTop;
        }
        else{
            x = evt.pageX-elementLeft;
            y = evt.pageY-elementTop;
    }

Node.js global proxy setting

Unfortunately, it seems that proxy information must be set on each call to http.request. Node does not include a mechanism for global proxy settings.

The global-tunnel-ng module on NPM appears to handle this, however:

var globalTunnel = require('global-tunnel-ng');

globalTunnel.initialize({
  host: '10.0.0.10',
  port: 8080,
  proxyAuth: 'userId:password', // optional authentication
  sockets: 50 // optional pool size for each http and https
});

After the global settings are establish with a call to initialize, both http.request and the request library will use the proxy information.

The module can also use the http_proxy environment variable:

process.env.http_proxy = 'http://proxy.example.com:3129';
globalTunnel.initialize();

Angular2 - Http POST request parameters

These answers are all outdated for those utilizing the HttpClient rather than Http. I was starting to go crazy thinking, "I have done the import of URLSearchParams but it still doesn't work without .toString() and the explicit header!"

With HttpClient, use HttpParams instead of URLSearchParams and note the body = body.append() syntax to achieve multiple params in the body since we are working with an immutable object:

login(userName: string, password: string): Promise<boolean> {
    if (!userName || !password) {
      return Promise.resolve(false);
    }

    let body: HttpParams = new HttpParams();
    body = body.append('grant_type', 'password');
    body = body.append('username', userName);
    body = body.append('password', password);

    return this.http.post(this.url, body)
      .map(res => {
        if (res) {          
          return true;
        }
        return false;
      })
      .toPromise();
  }

Angular 4 - get input value

If you dont want to use two way data binding. You can do this.

In HTML

<form (ngSubmit)="onSubmit($event)">
   <input name="player" value="Name">
</form>

In component

onSubmit(event: any) {
   return event.target.player.value;
}

How to View Oracle Stored Procedure using SQLPlus?

check your casing, the name is typically stored in upper case

SELECT * FROM all_source WHERE name = 'DAILY_UPDATE' ORDER BY TYPE, LINE;

Find a pair of elements from an array whose sum equals a given number

Another solution in Swift: the idea is to create an hash that store values of (sum - currentValue) and compare this to the current value of the loop. The complexity is O(n).

func findPair(list: [Int], _ sum: Int) -> [(Int, Int)]? {
    var hash = Set<Int>() //save list of value of sum - item.
    var dictCount = [Int: Int]() //to avoid the case A*2 = sum where we have only one A in the array
    var foundKeys  = Set<Int>() //to avoid duplicated pair in the result.

    var result = [(Int, Int)]() //this is for the result.
    for item in list {

        //keep track of count of each element to avoid problem: [2, 3, 5], 10 -> result = (5,5)
        if (!dictCount.keys.contains(item)) {
            dictCount[item] = 1
        } else {
            dictCount[item] = dictCount[item]! + 1
        }

        //if my hash does not contain the (sum - item) value -> insert to hash.
        if !hash.contains(sum-item) {
            hash.insert(sum-item)
        }

        //check if current item is the same as another hash value or not, if yes, return the tuple.
        if hash.contains(item) &&
            (dictCount[item] > 1 || sum != item*2) // check if we have item*2 = sum or not.
        {
            if !foundKeys.contains(item) && !foundKeys.contains(sum-item) {
                foundKeys.insert(item) //add to found items in order to not to add duplicated pair.
                result.append((item, sum-item))
            }
        }
    }
    return result
}

//test:
let a = findPair([2,3,5,4,1,7,6,8,9,5,3,3,3,3,3,3,3,3,3], 14) //will return (8,6) and (9,5)

How to check if a column exists in a datatable

It is much more accurate to use IndexOf:

If dt.Columns.IndexOf("ColumnName") = -1 Then
    'Column not exist
End If

If the Contains is used it would not differentiate between ColumName and ColumnName2.

Javascript - Get Image height

I was searching a solution to get height and width of an image using JavaScript. I found many, but all those solutions only worked when the image was present in browser cache.

Finally I found a solution to get the image height and width even if the image does not exist in the browser cache:

<script type="text/javascript">

  var imgHeight;
  var imgWidth;

  function findHHandWW() {
    imgHeight = this.height;
    imgWidth = this.width;
    return true;
  }

  function showImage(imgPath) {
    var myImage = new Image();
    myImage.name = imgPath;
    myImage.onload = findHHandWW;
    myImage.src = imgPath;
  }
</script>

Thanks,

Binod Suman

http://binodsuman.blogspot.com/2009/06/how-to-get-height-and-widht-of-image.html

How do I execute a bash script in Terminal?

This is an old thread, but I happened across it and I'm surprised nobody has put up a complete answer yet. So here goes...

The Executing a Command Line Script Tutorial!

Q: How do I execute this in Terminal?

Confusions and Conflicts:

  • You do not need an 'extension' (like .sh or .py or anything else), but it helps to keep track of things. It won't hurt. If the script name contains an extension, however, you must use it.
  • You do not need to be in any certain directory at all for any reason.
  • You do not need to type out the name of the program that runs the file (BASH or Python or whatever) unless you want to. It won't hurt.
  • You do not need sudo to do any of this. This command is reserved for running commands as another user or a 'root' (administrator) user. Great post here.

(A person who is just learning how to execute scripts should not be using this command unless there is a real need, like installing a new program. A good place to put your scripts is in your ~/bin folder. You can get there by typing cd ~/bin or cd $HOME/bin from the terminal prompt. You will have full permissions in that folder.)

To "execute this script" from the terminal on a Unix/Linux type system, you have to do three things:

  1. Tell the system the location of the script. (pick one)

    • Type the full path with the script name (e.g. /path/to/script.sh). You can verify the full path by typing pwd or echo $PWD in the terminal.
    • Execute from the same directory and use ./ for the path (e.g. ./script.sh). Easy.
    • Place the script in a directory that is on the system PATH and just type the name (e.g. script.sh). You can verify the system PATH by typing echo $PATH or echo -e ${PATH//:/\\n} if you want a neater list.
  2. Tell the system that the script has permission to execute. (pick one)

    • Set the "execute bit" by typing chmod +x /path/to/script.sh in the terminal.
    • You can also use chmod 755 /path/to/script.sh if you prefer numbers. There is a great discussion with a cool chart here.
  3. Tell the system the type of script. (pick one)

    • Type the name of the program before the script. (e.g. BASH /path/to/script.sh or PHP /path/to/script.php) If the script has an extension, such as .php or .py, it is part of the script name and you must include it.
    • Use a shebang, which I see you have (#!/bin/bash) in your example. If you have that as the first line of your script, the system will use that program to execute the script. No need for typing programs or using extensions.
    • Use a "portable" shebang. You can also have the system choose the version of the program that is first in the PATH by using #!/usr/bin/env followed by the program name (e.g. #!/usr/bin/env bash or #!/usr/bin/env python3). There are pros and cons as thoroughly discussed here.

git with development, staging and production branches

one of the best things about git is that you can change the work flow that works best for you.. I do use http://nvie.com/posts/a-successful-git-branching-model/ most of the time but you can use any workflow that fits your needs

How can I "disable" zoom on a mobile web page?

<script type="text/javascript">
document.addEventListener('touchmove', function (event) {
  if (event.scale !== 1) { event.preventDefault(); }
}, { passive: false });
</script>

Please Add the Script to Disable pinch, tap, focus Zoom

Python argparse: default value or specified value

The difference between:

parser.add_argument("--debug", help="Debug", nargs='?', type=int, const=1, default=7)

and

parser.add_argument("--debug", help="Debug", nargs='?', type=int, const=1)

is thus:

myscript.py => debug is 7 (from default) in the first case and "None" in the second

myscript.py --debug => debug is 1 in each case

myscript.py --debug 2 => debug is 2 in each case

Bootstrap - Removing padding or margin when screen size is smaller

The easy solution is to write something like that,

px-lg-1

mb-lg-5

By adding lg, the class will be applied only on large screens

JavaFX How to set scene background image

I know this is an old Question

But in case you want to do it programmatically or the java way

For Image Backgrounds; you can use BackgroundImage class

BackgroundImage myBI= new BackgroundImage(new Image("my url",32,32,false,true),
        BackgroundRepeat.REPEAT, BackgroundRepeat.NO_REPEAT, BackgroundPosition.DEFAULT,
          BackgroundSize.DEFAULT);
//then you set to your node
myContainer.setBackground(new Background(myBI));

For Paint or Fill Backgrounds; you can use BackgroundFill class

BackgroundFill myBF = new BackgroundFill(Color.BLUEVIOLET, new CornerRadii(1),
         new Insets(0.0,0.0,0.0,0.0));// or null for the padding
//then you set to your node or container or layout
myContainer.setBackground(new Background(myBF));

Keeps your java alive && your css dead..

Share Text on Facebook from Android App via ACTION_SEND

EDITED: with the new release of the official Facebook app for Android (July 14 2011) IT WORKS!!!

OLD: The examples above do not work if the user chooses the Facebook app for sharing, but they do work if the user chooses the Seesmic app to post to Facebook. I guess Seesmic have a better implementation of the Facebook API than Facebook!

Android Google Maps API V2 Zoom to Current Location

check this out:

    fun requestMyGpsLocation(context: Context, callback: (location: Location) -> Unit) {
        val request = LocationRequest()
        //        request.interval = 10000
        //        request.fastestInterval = 5000
        request.numUpdates = 1
        request.priority = LocationRequest.PRIORITY_HIGH_ACCURACY
        val client = LocationServices.getFusedLocationProviderClient(context)

        val permission = ContextCompat.checkSelfPermission(context,
            Manifest.permission.ACCESS_FINE_LOCATION )
        if (permission == PackageManager.PERMISSION_GRANTED) {
            client.requestLocationUpdates(request, object : LocationCallback() {
                override fun onLocationResult(locationResult: LocationResult?) {
                val location = locationResult?.lastLocation
                if (location != null)
                    callback.invoke(location)
            }
         }, null)
       }
     }

and

    fun zoomOnMe() {
        requestMyGpsLocation(this) { location ->
            mMap?.animateCamera(CameraUpdateFactory.newLatLngZoom(
                LatLng(location.latitude,location.longitude ), 13F ))
        }
    }

Save and load MemoryStream to/from a file

For anyone looking for the short versions:

var memoryStream = new MemoryStream(File.ReadAllBytes("1.dat"));

File.WriteAllBytes("1.dat", memoryStream.ToArray()); 

ReCaptcha API v2 Styling

You can use some CSS for Google reCAPTCHA v2 styling on your website:

– Change background, color of Google reCAPTCHA v2 widget:

.rc-anchor-light { 
background: #fff!important; 
color: #fff!important; }

or

.rc-anchor-normal{
background: #000 !important; 
color: #000 !important; }

– Resize the Google reCAPTCHA v2 widget by using this snippet:

.rc-anchor-light { 
transform:scale(0.9); 
-webkit-transform:scale(0.9); }

– Responsive your Google reCAPTCHA v2:

@media only screen and (min-width: 768px) {
.rc-anchor-light { 
transform:scale(0.85); 
-webkit-transform:scale(0.85); } 
}

All elements, property of CSS above that’s just for your reference. You can change them by yourself (only using CSS class selector).

Refer on OIW Blog - How To Edit CSS of Google reCAPTCHA (Re-style, Change Position, Resize reCAPTCHA Badge)

You can also find out Google reCAPTCHA v3's styling there.

Make $JAVA_HOME easily changable in Ubuntu

You need to put variable definition in the ~/.bashrc file.

From bash man page:

When an interactive shell that is not a login shell is started, bash reads and executes commands from /etc/bash.bashrc and ~/.bashrc, if these files exist.

how can the textbox width be reduced?

<input type='text' 
       name='t1'
       id='t1'
       maxlength=10
       placeholder='typing some text' >
<p></p>

This is the text box, it has a fixed length of 10 characters, and if you can try but this text box does not contain maximum length 10 character

How to keep environment variables when using sudo

First you need to export HTTP_PROXY. Second, you need to read man sudo carefully, and pay attention to the -E flag. This works:

$ export HTTP_PROXY=foof
$ sudo -E bash -c 'echo $HTTP_PROXY'

Here is the quote from the man page:

-E, --preserve-env
             Indicates to the security policy that the user wishes to preserve their
             existing environment variables.  The security policy may return an error
             if the user does not have permission to preserve the environment.

jQuery Validation plugin: disable validation for specified submit buttons

<button type="submit" formnovalidate="formnovalidate">submit</button>

also working

How to combine 2 plots (ggplot) into one plot?

Just combine them. I think this should work but it's untested:

p <- ggplot(visual1, aes(ISSUE_DATE,COUNTED)) + geom_point() + 
     geom_smooth(fill="blue", colour="darkblue", size=1)

p <- p + geom_point(data=visual2, aes(ISSUE_DATE,COUNTED)) + 
     geom_smooth(data=visual2, fill="red", colour="red", size=1)

print(p)

Server.MapPath("."), Server.MapPath("~"), Server.MapPath(@"\"), Server.MapPath("/"). What is the difference?

1) Server.MapPath(".") -- Returns the "Current Physical Directory" of the file (e.g. aspx) being executed.

Ex. Suppose D:\WebApplications\Collage\Departments

2) Server.MapPath("..") -- Returns the "Parent Directory"

Ex. D:\WebApplications\Collage

3) Server.MapPath("~") -- Returns the "Physical Path to the Root of the Application"

Ex. D:\WebApplications\Collage

4) Server.MapPath("/") -- Returns the physical path to the root of the Domain Name

Ex. C:\Inetpub\wwwroot

Is there a good JSP editor for Eclipse?

"Web Page Editor (optional)" package from the Eclipse Galileo/Helios update site has the following very minor quirks in a JSP editor:

  • Auto-commenting in Java code fragments does not work (Ctrl /); [fixed in Helios SR2]
  • [present in Galileo, fixed in Eclipse Helios SR1] If a Java code fragment has errors that are already fixed, the editor does not remove the error marks until you modify the erroneous place or close/reopen the file being edited;

This was valid at Dec 7, 2010.

Objective-C ARC: strong vs retain and weak vs assign

Strong:

  • Property will not Destroy but Only once you set the property to nil will the object get destroyed
  • By default all instance variables and local variables are strong pointers.
  • You use strong only if you need to retain the object.
  • We generally use strong for UIViewControllers (UI item's parents)
  • IOS 4 (non-ARC) We Can Use Retain KeyWord
  • IOS 5(ARC) We Can Use Strong Keyword

Example: @property (strong, nonatomic) ViewController *viewController;

@synthesize viewController;

Weak

By Default automatically get and set to nil

  • We generally use weak for IBOutlets (UIViewController's Childs) and delegate
  • the same thing as assign, no retain or release

Example : @property (weak, nonatomic) IBOutlet UIButton *myButton;

@synthesize myButton;

How/When does Execute Shell mark a build as failure in Jenkins?

In my opinion, turning off the -e option to your shell is a really bad idea. Eventually one of the commands in your script will fail due to transient conditions like out of disk space or network errors. Without -e Jenkins won't notice and will continue along happily. If you've got Jenkins set up to do deployment, that may result in bad code getting pushed and bringing down your site.

If you have a line in your script where failure is expected, like a grep or a find, then just add || true to the end of that line. That ensures that line will always return success.

If you need to use that exit code, you can either hoist the command into your if statement:

grep foo bar; if [ $? == 0 ]; then ...    -->   if grep foo bar; then ...

Or you can capture the return code in your || clause:

grep foo bar || ret=$?

get path for my .exe

in visualstudio 2008 you could use this code :

   var _assembly = System.Reflection.Assembly
               .GetExecutingAssembly().GetName().CodeBase;

   var _path = System.IO.Path.GetDirectoryName(_assembly) ;

How to enable PHP short tags?

For docker add this step to Dockerfile

  ARG phpIniPath=/path/to/your/php.ini

  RUN sed -i -e 's/^short_open_tag\s*=.*/short_open_tag = On/' $phpIniPath  

The identity used to sign the executable is no longer valid

These were the reasons I had this error:

The App ID didn't have my iOS Developer Certificate checked (I'm a member of an Enterprise program) and I had 2 provisioning profiles with the same App ID in my Mac. I deleted one.

Hopefully this helps someone.

How to use lodash to find and return an object from Array?

The argument passed to the callback is one of the elements of the array. The elements of your array are objects of the form {description: ..., id: ...}.

var delete_id = _.result(_.find(savedViews, function(obj) {
    return obj.description === view;
}), 'id');

Yet another alternative from the docs you linked to (lodash v3):

_.find(savedViews, 'description', view);

Lodash v4:

_.find(savedViews, ['description', view]);

Upload Image using POST form data in Python-requests

In case if you were to pass the image as part of JSON along with other attributes, you can use the below snippet.
client.py

import base64
import json                    

import requests

api = 'http://localhost:8080/test'
image_file = 'sample_image.png'

with open(image_file, "rb") as f:
    im_bytes = f.read()        
im_b64 = base64.b64encode(im_bytes).decode("utf8")

headers = {'Content-type': 'application/json', 'Accept': 'text/plain'}
  
payload = json.dumps({"image": im_b64, "other_key": "value"})
response = requests.post(api, data=payload, headers=headers)
try:
    data = response.json()     
    print(data)                
except requests.exceptions.RequestException:
    print(response.text)

server.py

import io
import json                    
import base64                  
import logging             
import numpy as np
from PIL import Image

from flask import Flask, request, jsonify, abort

app = Flask(__name__)          
app.logger.setLevel(logging.DEBUG)
  
  
@app.route("/test", methods=['POST'])
def test_method():         
    # print(request.json)      
    if not request.json or 'image' not in request.json: 
        abort(400)
             
    # get the base64 encoded string
    im_b64 = request.json['image']

    # convert it into bytes  
    img_bytes = base64.b64decode(im_b64.encode('utf-8'))

    # convert bytes data to PIL Image object
    img = Image.open(io.BytesIO(img_bytes))

    # PIL image object to numpy array
    img_arr = np.asarray(img)      
    print('img shape', img_arr.shape)

    # process your img_arr here    
    
    # access other keys of json
    # print(request.json['other_key'])

    result_dict = {'output': 'output_key'}
    return result_dict
  
  
def run_server_api():
    app.run(host='0.0.0.0', port=8080)
  
  
if __name__ == "__main__":     
    run_server_api()

Converting NSString to NSDate (and back again)

NSString *mystr=@"Your string date";

NSCalendar *cal = [NSCalendar currentCalendar];
NSDate *now = [dateFormatter dateFromString:mystr];

Nslog(@"%@",now);

If you want set the format use below code:

NSString *dateString = @"01-02-2010";
NSDateFormatter *dateFormatter = [[NSDateFormatter alloc] init];

// this is important - we set our input date format to match our input string
// if format doesn't match you'll get nil from your string, so be careful
[dateFormatter setDateFormat:@"dd-MM-yyyy"];
NSDate *dateFromString = [[NSDate alloc] init];

// voila!
dateFromString = [dateFormatter dateFromString:dateString];
Nslog(@"%@",[dateFormatter dateFromString:dateString]);

JavaScript file not updating no matter what I do

Don't forget to check any errors in webpack compilation. Sometimes the application.js in app/javascript/packs/ doesn't reload due to webpack compilation error.

android layout with visibility GONE

<TextView
                android:id="@+id/layone"
                android:layout_width="wrap_content"
                android:layout_height="wrap_content"
                android:text="Previous Page"
                android:textColor="#000000"
                android:textSize="16dp"
                android:paddingLeft="10dp"
                android:layout_marginTop="10dp"
                android:visibility="gone" />

layone is a TextView.
You got your id wrong.

LinearLayout layone= (LinearLayout) view.findViewById(R.id.laytwo);// change id here

layone.setVisibility(View.VISIBLE);

should do the job.

or change like this to show the TextView:

TextView layone= (TextView) view.findViewById(R.id.layone);

    layone.setVisibility(View.VISIBLE);

GIT clone repo across local file system in windows

While UNC path is supported since Git 2.21 (Feb. 2019, see below), Git 2.24 (Q4 2019) will allow

git clone file://192.168.10.51/code

No more file:////xxx, 'file://' is enough to refer to an UNC path share.
See "Git Fetch Error with UNC".


Note, since 2016 and the MingW-64 git.exe packaged with Git for Windows, an UNC path is supported.
(See "How are msys, msys2, and MinGW-64 related to each other?")

And with Git 2.21 (Feb. 2019), this support extends even in in an msys2 shell (with quotes around the UNC path).

See commit 9e9da23, commit 5440df4 (17 Jan 2019) by Johannes Schindelin (dscho).
Helped-by: Kim Gybels (Jeff-G).
(Merged by Junio C Hamano -- gitster -- in commit f5dd919, 05 Feb 2019)

Before Git 2.21, due to a quirk in Git's method to spawn git-upload-pack, there is a problem when passing paths with backslashes in them: Git will force the command-line through the shell, which has different quoting semantics in Git for Windows (being an MSYS2 program) than regular Win32 executables such as git.exe itself.

The symptom is that the first of the two backslashes in UNC paths of the form \\myserver\folder\repository.git is stripped off.

This is mitigated now:

mingw: special-case arguments to sh

The MSYS2 runtime does its best to emulate the command-line wildcard expansion and de-quoting which would be performed by the calling Unix shell on Unix systems.

Those Unix shell quoting rules differ from the quoting rules applying to Windows' cmd and Powershell, making it a little awkward to quote command-line parameters properly when spawning other processes.

In particular, git.exe passes arguments to subprocesses that are not intended to be interpreted as wildcards, and if they contain backslashes, those are not to be interpreted as escape characters, e.g. when passing Windows paths.

Note: this is only a problem when calling MSYS2 executables, not when calling MINGW executables such as git.exe. However, we do call MSYS2 executables frequently, most notably when setting the use_shell flag in the child_process structure.

There is no elegant way to determine whether the .exe file to be executed is an MSYS2 program or a MINGW one.
But since the use case of passing a command line through the shell is so prevalent, we need to work around this issue at least when executing sh.exe.

Let's introduce an ugly, hard-coded test whether argv[0] is "sh", and whether it refers to the MSYS2 Bash, to determine whether we need to quote the arguments differently than usual.

That still does not fix the issue completely, but at least it is something.

Incidentally, this also fixes the problem where git clone \\server\repo failed due to incorrect handling of the backslashes when handing the path to the git-upload-pack process.

Further, we need to take care to quote not only whitespace and backslashes, but also curly brackets.
As aliases frequently go through the MSYS2 Bash, and as aliases frequently get parameters such as HEAD@{yesterday}, this is really important.

See t/t5580-clone-push-unc.sh

How can I count the numbers of rows that a MySQL query returned?

The basics

To get the number of matching rows in SQL you would usually use COUNT(*). For example:

SELECT COUNT(*) FROM some_table

To get that in value in PHP you need to fetch the value from the first column in the first row of the returned result. An example using PDO and mysqli is demonstrated below.

However, if you want to fetch the results and then still know how many records you fetched using PHP, you could use count() or avail of the pre-populated count in the result object if your DB API offers it e.g. mysqli's num_rows.

Using MySQLi

Using mysqli you can fetch the first row using fetch_row() and then access the 0 column, which should contain the value of COUNT(*).

// your connection code
mysqli_report(MYSQLI_REPORT_ERROR | MYSQLI_REPORT_STRICT);
$mysqli = new \mysqli('localhost', 'dbuser', 'yourdbpassword', 'db_name');
$mysqli->set_charset('utf8mb4');

// your SQL statement
$stmt = $mysqli->prepare('SELECT COUNT(*) FROM some_table WHERE col1=?');
$stmt->bind_param('s', $someVariable);
$stmt->execute();
$result = $stmt->get_result();

// now fetch 1st column of the 1st row 
$count = $result->fetch_row()[0];

echo $count;

If you want to fetch all the rows, but still know the number of rows then you can use num_rows or count().

// your SQL statement
$stmt = $mysqli->prepare('SELECT col1, col2 FROM some_table WHERE col1=?');
$stmt->bind_param('s', $someVariable);
$stmt->execute();
$result = $stmt->get_result();

// If you want to use the results, but still know how many records were fetched
$rows = $result->fetch_all(MYSQLI_ASSOC);

echo $result->num_rows;
// or
echo count($rows);

Using PDO

Using PDO is much simpler. You can directly call fetchColumn() on the statement to get a single column value.

// your connection code
$pdo = new \PDO('mysql:host=localhost;dbname=test;charset=utf8mb4', 'root', '', [
    \PDO::ATTR_EMULATE_PREPARES => false,
    \PDO::ATTR_ERRMODE => \PDO::ERRMODE_EXCEPTION
]);

// your SQL statement
$stmt = $pdo->prepare('SELECT COUNT(*) FROM some_table WHERE col1=?');
$stmt->execute([
    $someVariable
]);

// Fetch the first column of the first row
$count = $stmt->fetchColumn();

echo $count;

Again, if you need to fetch all the rows anyway, then you can get it using count() function.

// your SQL statement
$stmt = $pdo->prepare('SELECT col1, col2 FROM some_table WHERE col1=?');
$stmt->execute([
    $someVariable
]);

// If you want to use the results, but still know how many records were fetched
$rows = $stmt->fetchAll();

echo count($rows);

PDO's statement doesn't offer pre-computed property with the number of rows fetched, but it has a method called rowCount(). This method can tell you the number of rows returned in the result, but it cannot be relied upon and it is generally not recommended to use.

(SC) DeleteService FAILED 1072

make sure the service is stopped, the services control panel is closed, and no open file handles are open by the service.

Also make sure ProcessExplorer is not running.

PHP: Call to undefined function: simplexml_load_string()

For PHP 7 and Ubuntu 14.04 the procedure is follows. Since PHP 7 is not in the official Ubuntu PPAs you likely installed it through Ondrej Surý's PPA (sudo add-apt-repository ppa:ondrej/php). Go to /etc/php/7.0/fpm and edit php.ini, uncomment to following line:

extension=php_xmlrpc.dll

Then simply install php7.0-xml:

sudo apt-get install php7.0-xml

And restart PHP:

sudo service php7.0-fpm restart

And restart Apache:

sudo service apache2 restart

If you are on a later Ubuntu version where PHP 7 is included, the procedure is most likely the same as well (except adding any 3rd party repository).

How to compare two columns in Excel (from different sheets) and copy values from a corresponding column if the first two columns match?

Vlookup is good if the reference values (column A, sheet 1) are in ascending order. Another option is Index and Match, which can be used no matter the order (As long as the values in column a, sheet 1 are unique)

This is what you would put in column B on sheet 2

=INDEX(Sheet1!A$1:B$6,MATCH(A1,Sheet1!A$1:A$6),2)

Setting Sheet1!A$1:B$6 and Sheet1!A$1:A$6 as named ranges makes it a little more user friendly.

java - path to trustStore - set property doesn't work?

You have a typo - it is trustStore.

Apart from setting the variables with System.setProperty(..), you can also use

-Djavax.net.ssl.keyStore=path/to/keystore.jks

Half circle with CSS (border, outline only)

I use a percentage method to achieve

        border: 3px solid rgb(1, 1, 1);
        border-top-left-radius: 100% 200%;
        border-top-right-radius: 100% 200%;

Infinite Recursion with Jackson JSON and Hibernate JPA issue

I have faced same issue, add jsonbackref and jsonmanagedref and please make sure @override equals and hashCode methods , this definitely fix this issue.

Powershell command to hide user from exchange address lists

You can use the following script, just replace DOMAIN with the name of your domain. When executed it will prompt you for a userlogin then hide that user's account from the address lists.

$name=Read-Host "Enter login name of user to hide"
Set-Mailbox -Identity DOMAIN\$name -HiddenFromAddressListsEnabled $true

Brian.

css divide width 100% to 3 column

How about using the CSS3 flex model:

HTML Code:

<div id="wrapper">
    <div id="c1">c1</div>
    <div id="c2">c2</div>
    <div id="c3">c3</div>
</div>  

CSS Code:

*{
    margin:0;
    padding:0;
}

#wrapper{
    display:-webkit-flex;
    -webkit-justify-content:center;

    display:flex;
    justify-content:center;

}

#wrapper div{
    -webkit-flex:1;
    flex:1;
    border:thin solid #777;

}

How to install SQL Server 2005 Express in Windows 8

Microsoft SQL Server 2005 Express Edition Service Pack 4 on Windows Server 2012 R2

Those steps are based on previous howto from https://stackoverflow.com/users/2385/eduardo-molteni

  1. download SQLEXPR.EXE
  2. run SQLEXPR.EXE
  3. copy c:\generated_installation_dir to inst.bak
  4. quit install
  5. run inst.bak/setuip/sqlncli_x64.msi
  6. run SQLEXPR.EXE
  7. enjoy!

This works with Microsoft SQL Server 2005 Express Edition Service Pack 4 http://www.microsoft.com/en-us/download/details.aspx?id=184

Invalid Host Header when ngrok tries to connect to React dev server

I used this set up in a react app that works. I created a config file named configstrp.js that contains the following:

module.exports = {
ngrok: {
// use the local frontend port to connect
enabled: process.env.NODE_ENV !== 'production',
port: process.env.PORT || 3000,
subdomain: process.env.NGROK_SUBDOMAIN,
authtoken: process.env.NGROK_AUTHTOKEN
},   }

Require the file in the server.

const configstrp      = require('./config/configstrp.js');
const ngrok = configstrp.ngrok.enabled ? require('ngrok') : null;

and connect as such

if (ngrok) {
console.log('If nGronk')
ngrok.connect(
    {
    addr: configstrp.ngrok.port,
    subdomain: configstrp.ngrok.subdomain,
    authtoken: configstrp.ngrok.authtoken,
    host_header:3000
  },
  (err, url) => {
    if (err) {

    } else {

    }
   }
  );
 }

Do not pass a subdomain if you do not have a custom domain

javascript filter array multiple conditions

const users = [{
    name: 'John',
    email: '[email protected]',
    age: 25,
    address: 'USA'
  },
  {
    name: 'Tom',
    email: '[email protected]',
    age: 35,
    address: 'England'
  },
  {
    name: 'Mark',
    email: '[email protected]',
    age: 28,
    address: 'England'
  }
];

const filteredUsers = users.filter(({ name, age }) => name === 'Tom' && age === 35)

console.log(filteredUsers)

How to download all files (but not HTML) from a website using wget?

You may try:

wget --user-agent=Mozilla --content-disposition --mirror --convert-links -E -K -p http://example.com/

Also you can add:

-A pdf,ps,djvu,tex,doc,docx,xls,xlsx,gz,ppt,mp4,avi,zip,rar

to accept the specific extensions, or to reject only specific extensions:

-R html,htm,asp,php

or to exclude the specific areas:

-X "search*,forum*"

If the files are ignored for robots (e.g. search engines), you've to add also: -e robots=off

How can I insert binary file data into a binary SQL field using a simple insert statement?

If you mean using a literal, you simply have to create a binary string:

insert into Files (FileId, FileData) values (1, 0x010203040506)

And you will have a record with a six byte value for the FileData field.


You indicate in the comments that you want to just specify the file name, which you can't do with SQL Server 2000 (or any other version that I am aware of).

You would need a CLR stored procedure to do this in SQL Server 2005/2008 or an extended stored procedure (but I'd avoid that at all costs unless you have to) which takes the filename and then inserts the data (or returns the byte string, but that can possibly be quite long).


In regards to the question of only being able to get data from a SP/query, I would say the answer is yes, because if you give SQL Server the ability to read files from the file system, what do you do when you aren't connected through Windows Authentication, what user is used to determine the rights? If you are running the service as an admin (God forbid) then you can have an elevation of rights which shouldn't be allowed.