Programs & Examples On #Password checker

jquery equivalent for JSON.stringify

There is no such functionality in jQuery. Use JSON.stringify or alternatively any jQuery plugin with similar functionality (e.g jquery-json).

Easiest way to open a download window without navigating away from the page

If the link is to a valid file url, simply assigning window.location.href will work.

However, sometimes the link is not valid, and an iFrame is required.

Do your normal event.preventDefault to prevent the window from opening, and if you are using jQuery, this will work:

$('<iframe>').attr('src', downloadThing.attr('href')).appendTo('body').on("load", function() {
   $(this).remove();
});

Event listener for when element becomes visible?

my solution:

; (function ($) {
$.each([ "toggle", "show", "hide" ], function( i, name ) {
    var cssFn = $.fn[ name ];
    $.fn[ name ] = function( speed, easing, callback ) {
        if(speed == null || typeof speed === "boolean"){
            var ret=cssFn.apply( this, arguments )
            $.fn.triggerVisibleEvent.apply(this,arguments)
            return ret
        }else{
            var that=this
            var new_callback=function(){
                callback.call(this)
                $.fn.triggerVisibleEvent.apply(that,arguments)
            }
            var ret=this.animate( genFx( name, true ), speed, easing, new_callback )
            return ret
        }
    };
});

$.fn.triggerVisibleEvent=function(){
    this.each(function(){
        if($(this).is(':visible')){
            $(this).trigger('visible')
            $(this).find('[data-trigger-visible-event]').triggerVisibleEvent()
        }
    })
}
})(jQuery);

for example:

if(!$info_center.is(':visible')){
    $info_center.attr('data-trigger-visible-event','true').one('visible',processMoreLessButton)
}else{
    processMoreLessButton()
}

function processMoreLessButton(){
//some logic
}

What does 'IISReset' do?

It stops and starts the services that IIS consists of.

You can think of it as closing the relevant program and starting it up again.

How to duplicate sys.stdout to a log file?

I had this same issue before and found this snippet very useful:

class Tee(object):
    def __init__(self, name, mode):
        self.file = open(name, mode)
        self.stdout = sys.stdout
        sys.stdout = self
    def __del__(self):
        sys.stdout = self.stdout
        self.file.close()
    def write(self, data):
        self.file.write(data)
        self.stdout.write(data)
    def flush(self):
        self.file.flush()

from: http://mail.python.org/pipermail/python-list/2007-May/438106.html

How to work offline with TFS

I just wanted to include a link to a resolution to an issue I was having with VS2008 and TFS08.

I accidently opened my solution without being connected to my network and was not able to get it "back the way it was" and had to rebind every time I openned.

I found the solution here; http://www.fkollmann.de/v2/post/Visual-Studio-2008-refuses-to-bind-to-TFS-or-to-open-solution-source-controlled.aspx

Basically, you need to open the "Connect to Team Foundation Server" and then "Servers..." once there, Delete/Remove your server and re-add it. This fixed my issue.

How to get a cookie from an AJAX response?

xhr.getResponseHeader('Set-Cookie');

It won't work for me.

I use this

function getCookie(cname) {
    var name = cname + "=";
    var ca = document.cookie.split(';');
    for(var i=0; i<ca.length; i++) {
        var c = ca[i];
        while (c.charAt(0)==' ') c = c.substring(1);
        if (c.indexOf(name) != -1) return c.substring(name.length,c.length);
    }
    return "";
} 

success: function(output, status, xhr) {
    alert(getCookie("MyCookie"));
},

http://www.w3schools.com/js/js_cookies.asp

PowerShell array initialization

The solution I found was to use the New-Object cmdlet to initialize an array of the proper size.

$array = new-object object[] 5 
for($i=0; $i -lt $array.Length;$i++)
{
    $array[$i] = $FALSE
}

Getting file names without extensions

using System;

using System.IO;

public class GetwithoutExtension
{

    public static void Main()
    {
        //D:Dir dhould exists in ur system
        DirectoryInfo dir1 = new DirectoryInfo(@"D:Dir");
        FileInfo [] files = dir1.GetFiles("*xls", SearchOption.AllDirectories);
        foreach (FileInfo f in files)
        {
            string filename = f.Name.ToString();
            filename= filename.Replace(".xls", "");
            Console.WriteLine(filename);
        }
        Console.ReadKey();

    }

}

'Access-Control-Allow-Origin' issue when API call made from React (Isomorphic app)

CORS is a browser feature. Servers need to opt into CORS to allow browsers to bypass same-origin policy. Your server would not have that same restriction and be able to make requests to any server with a public API. https://developer.mozilla.org/en-US/docs/Web/HTTP/Access_control_CORS

Create an endpoint on your server with CORS enabled that can act as a proxy for your web app.

Are there any standard exit status codes in Linux?

Programs return a 16 bit exit code. If the program was killed with a signal then the high order byte contains the signal used, otherwise the low order byte is the exit status returned by the programmer.

How that exit code is assigned to the status variable $? is then up to the shell. Bash keeps the lower 7 bits of the status and then uses 128 + (signal nr) for indicating a signal.

The only "standard" convention for programs is 0 for success, non-zero for error. Another convention used is to return errno on error.

Why doesn't Dijkstra's algorithm work for negative weight edges?

Try Dijkstra's algorithm on the following graph, assuming A is the source node and D is the destination, to see what is happening:

Graph

Note that you have to follow strictly the algorithm definition and you should not follow your intuition (which tells you the upper path is shorter).

The main insight here is that the algorithm only looks at all directly connected edges and it takes the smallest of these edge. The algorithm does not look ahead. You can modify this behavior , but then it is not the Dijkstra algorithm anymore.

getting JRE system library unbound error in build path

I too faced the same issue. I followed the following steps to resolve my issue -

  • Right click on your project -> Properties
  • Select Java Build Path in the left menu
  • Select Libraries tab
  • Under the module path, select the troublesome JRE entry
  • Click on Edit button
  • Select Workspace default JRE.
  • Click on Finish button

If the above steps don't work for you, instead of Workspace default JRE, you can choose an Alternate JRE and give the path to the JRE that you want to point.

CMake error at CMakeLists.txt:30 (project): No CMAKE_C_COMPILER could be found

I know this question is about visual studio 2015. I faced this issue with visual studio 2017. When searched on google I landed to this page. After looking at first 2,3 answers I realized this is the problem with vc++ installation. Installing the workload "Desktop development with c++" resolved the issue.

Desktop development with c++

Single line if statement with 2 actions

Sounds like you really want a Dictionary<int, string> or possibly a switch statement...

You can do it with the conditional operator though:

userType = user.Type == 0 ? "Admin"
         : user.Type == 1 ? "User"
         : user.Type == 2 ? "Employee"
         : "The default you didn't specify";

While you could put that in one line, I'd strongly urge you not to.

I would normally only do this for different conditions though - not just several different possible values, which is better handled in a map.

What is a "callback" in C and how are they implemented?

It is lot easier to understand an idea through example. What have been told about callback function in C so far are great answers, but probably the biggest benefit of using the feature is to keep the code clean and uncluttered.

Example

The following C code implements quick sorting. The most interesting line in the code below is this one, where we can see the callback function in action:

qsort(arr,N,sizeof(int),compare_s2b);

The compare_s2b is the name of function which qsort() is using to call the function. This keeps qsort() so uncluttered (hence easier to maintain). You just call a function by name from inside another function (of course, the function prototype declaration, at the least, must precde before it can be called from another function).

The Complete Code

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

int arr[]={56,90,45,1234,12,3,7,18};
//function prototype declaration 

int compare_s2b(const void *a,const void *b);

int compare_b2s(const void *a,const void *b);

//arranges the array number from the smallest to the biggest
int compare_s2b(const void* a, const void* b)
{
    const int* p=(const int*)a;
    const int* q=(const int*)b;

    return *p-*q;
}

//arranges the array number from the biggest to the smallest
int compare_b2s(const void* a, const void* b)
{
    const int* p=(const int*)a;
    const int* q=(const int*)b;

    return *q-*p;
}

int main()
{
    printf("Before sorting\n\n");

    int N=sizeof(arr)/sizeof(int);

    for(int i=0;i<N;i++)
    {
        printf("%d\t",arr[i]);
    }

    printf("\n");

    qsort(arr,N,sizeof(int),compare_s2b);

    printf("\nSorted small to big\n\n");

    for(int j=0;j<N;j++)
    {
        printf("%d\t",arr[j]);
    }

    qsort(arr,N,sizeof(int),compare_b2s);

    printf("\nSorted big to small\n\n");

    for(int j=0;j<N;j++)
    {
        printf("%d\t",arr[j]);
    }

    exit(0);
}

How to uninstall / completely remove Oracle 11g (client)?

Do everything suggested by ziesemer.

You may also want to remove from the registry:

HKEY_LOCAL_MACHINE\SOFTWARE\ODBC\ODBCINST.INI\<any Ora* drivers> keys     

HKEY_LOCAL_MACHINE\SOFTWARE\ODBC\ODBCINST.INI\ODBC Drivers<any Ora* driver> values

So they no longer appear in the "ODBC Drivers that are installed on your system" in ODBC Data Source Administrator

How to make HTML code inactive with comments

Behold HTML comments:

<!-- comment -->

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

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

How do I rename a MySQL schema?

If you're on the Model Overview page you get a tab with the schema. If you rightclick on that tab you get an option to "edit schema". From there you can rename the schema by adding a new name, then click outside the field. This goes for MySQL Workbench 5.2.30 CE

Edit: On the model overview it's under Physical Schemata

Screenshot:

enter image description here

Convert List to Pandas Dataframe Column

Use:

L = ['Thanks You', 'Its fine no problem', 'Are you sure']

#create new df 
df = pd.DataFrame({'col':L})
print (df)

                   col
0           Thanks You
1  Its fine no problem
2         Are you sure

df = pd.DataFrame({'oldcol':[1,2,3]})

#add column to existing df 
df['col'] = L
print (df)
   oldcol                  col
0       1           Thanks You
1       2  Its fine no problem
2       3         Are you sure

Thank you DYZ:

#default column name 0
df = pd.DataFrame(L)
print (df)
                     0
0           Thanks You
1  Its fine no problem
2         Are you sure

Where does Chrome store cookies?

Actually the current browsing path to the Chrome cookies in the address bar is: chrome://settings/content/cookies

map function for objects (instead of arrays)

Hey wrote a little mapper function that might help.

    function propertyMapper(object, src){
         for (var property in object) {   
           for (var sourceProp in src) {
               if(property === sourceProp){
                 if(Object.prototype.toString.call( property ) === '[object Array]'){
                   propertyMapper(object[property], src[sourceProp]);
                   }else{
                   object[property] = src[sourceProp];
                }
              }
            }
         }
      }

Bootstrap: How to center align content inside column?

You can do this by adding a div i.e. centerBlock. And give this property in CSS to center the image or any content. Here is the code:

<div class="container">
    <div class="row">
        <div class="col-sm-4 col-md-4 col-lg-4">
            <div class="centerBlock">
                <img class="img-responsive" src="img/some-image.png" title="This image needs to be centered">
            </div>
        </div>
        <div class="col-sm-8 col-md-8 col-lg-8">
            Some content not important at this moment
        </div>
    </div>
</div>


// CSS

.centerBlock {
  display: table;
  margin: auto;
}

Count how many files in directory PHP

You can simply do the following :

$fi = new FilesystemIterator(__DIR__, FilesystemIterator::SKIP_DOTS);
printf("There were %d Files", iterator_count($fi));

Selenium WebDriver: I want to overwrite value in field instead of appending to it with sendKeys using Java

Okay, it is a few days ago... In my current case, the answer from ZloiAdun does not work for me, but brings me very close to my solution...

Instead of:

element.sendKeys(Keys.chord(Keys.CONTROL, "a"), "55");

the following code makes me happy:

element.sendKeys(Keys.HOME, Keys.chord(Keys.SHIFT, Keys.END), "55");

So I hope that helps somebody!

(.text+0x20): undefined reference to `main' and undefined reference to function

This rule

main: producer.o consumer.o AddRemove.o
   $(COMPILER) -pthread $(CCFLAGS) -o producer.o consumer.o AddRemove.o

is wrong. It says to create a file named producer.o (with -o producer.o), but you want to create a file named main. Please excuse the shouting, but ALWAYS USE $@ TO REFERENCE THE TARGET:

main: producer.o consumer.o AddRemove.o
   $(COMPILER) -pthread $(CCFLAGS) -o $@ producer.o consumer.o AddRemove.o

As Shahbaz rightly points out, the gmake professionals would also use $^ which expands to all the prerequisites in the rule. In general, if you find yourself repeating a string or name, you're doing it wrong and should use a variable, whether one of the built-ins or one you create.

main: producer.o consumer.o AddRemove.o
   $(COMPILER) -pthread $(CCFLAGS) -o $@ $^

django MultiValueDictKeyError error, how do I deal with it

For me, this error occurred in my django project because of the following:

  1. I inserted a new hyperlink in my home.html present in templates folder of my project as below:

    _x000D_
    _x000D_
    <input type="button" value="About" onclick="location.href='{% url 'about' %}'">
    _x000D_
    _x000D_
    _x000D_

  2. In views.py, I had the following definitions of count and about:

   def count(request):
           fulltext = request.GET['fulltext']
           wordlist = fulltext.split()
           worddict = {}
           for word in wordlist:
               if word in worddict:
                   worddict[word] += 1
               else:
                   worddict[word] = 1
                   worddict = sorted(worddict.items(), key = operator.itemgetter(1),reverse=True)
           return render(request,'count.html', 'fulltext':fulltext,'count':len(wordlist),'worddict'::worddict})

   def about(request): 
       return render(request,"about.html")
  1. In urls.py, I had the following url patterns:
    urlpatterns = [
        path('admin/', admin.site.urls),
        path('',views.homepage,name="home"),
        path('eggs',views.eggs),
        path('count/',views.count,name="count"),
        path('about/',views.count,name="about"),
    ]

As can be seen in no. 3 above,in the last url pattern, I was incorrectly calling views.count whereas I needed to call views.about. This line fulltext = request.GET['fulltext'] in count function (which was mistakenly called because of wrong entry in urlpatterns) of views.py threw the multivaluedictkeyerror exception.

Then I changed the last url pattern in urls.py to the correct one i.e. path('about/',views.about,name="about"), and everything worked fine.

Apparently, in general a newbie programmer in django can make the mistake I made of wrongly calling another view function for a url, which might be expecting different set of parameters or passing different set of objects in its render call, rather than the intended behavior.

Hope this helps some newbie programmer to django.

Using VBA code, how to export Excel worksheets as image in Excel 2003?

Solution without charts

Function SelectionToPicture(nome)

'save location ( change if you want )
FName = CreateObject("WScript.Shell").SpecialFolders("Desktop") & "\" & nome & ".jpg"

'copy selection and get size
Selection.CopyPicture xlScreen, xlBitmap
w = Selection.Width
h = Selection.Height



With ThisWorkbook.ActiveSheet

    .Activate

    Dim chtObj As ChartObject
    Set chtObj = .ChartObjects.Add(100, 30, 400, 250)
    chtObj.Name = "TemporaryPictureChart"

    'resize obj to picture size
    chtObj.Width = w
    chtObj.Height = h

    ActiveSheet.ChartObjects("TemporaryPictureChart").Activate
    ActiveChart.Paste

    ActiveChart.Export FileName:=FName, FilterName:="jpg"

    chtObj.Delete

End With
End Function

How to to send mail using gmail in Laravel?

If you're developing on an XAMPP, then you'll need an SMTP service to send the email. Try using a MailGun account. It's free and easy to use.

Correct way of looping through C++ arrays

string texts[] = {"Apple", "Banana", "Orange"};
for( unsigned int a = 0; a < sizeof(texts); a = a + 1 )
{
    cout << "value of a: " << texts[a] << endl;
}

Nope. Totally a wrong way of iterating through an array. sizeof(texts) is not equal to the number of elements in the array!

The modern, C++11 ways would be to:

  • use std::array if you want an array whose size is known at compile-time; or
  • use std::vector if its size depends on runtime

Then use range-for when iterating.

#include <iostream>
#include <array>


int main() {
    std::array<std::string, 3> texts = {"Apple", "Banana", "Orange"};
    // ^ An array of 3 elements with the type std::string

    for(const auto& text : texts) {   // Range-for!
        std::cout << text << std::endl;
    }
}

Live example


You may ask, how is std::array better than the ol' C array? The answer is that it has the additional safety and features of other standard library containers, mostly closely resembling std::vector. Further, The answer is that it doesn't have the quirks of decaying to pointers and thus losing type information, which, once you lose the original array type, you can't use range-for or std::begin/end on it.

RegEx to parse or validate Base64 data

Neither a ":" nor a "." will show up in valid Base64, so I think you can unambiguously throw away the http://www.stackoverflow.com line. In Perl, say, something like

my $sanitized_str = join q{}, grep {!/[^A-Za-z0-9+\/=]/} split /\n/, $str;

say decode_base64($sanitized_str);

might be what you want. It produces

This is simple ASCII Base64 for StackOverflow exmaple.

Referencing value in a closed Excel workbook using INDIRECT?

In Excel 2016 at least, you can use INDIRECT with a full path reference; the entire reference (including sheet name) needs to be enclosed by ' characters.

So this should work for you:

= INDIRECT("'C:\data\[myExcelFile.xlsm]" & C13 & "'!$A$1")

Note the closing ' in the last string (ie '!$A$1 surrounded by "")

Does overflow:hidden applied to <body> work on iPhone Safari?

A CSS keyword value that resets a property's value to the default specified by the browser in its UA stylesheet, as if the webpage had not included any CSS. For example, display:revert on a <div> would result in display:block.

overflow: revert;

I think this will work properly

Getting net::ERR_UNKNOWN_URL_SCHEME while calling telephone number from HTML page in Android

I had this issue occurring with mailto: and tel: links inside an iframe (in Chrome, not a webview). Clicking the links would show the grey "page not found" page and inspecting the page showed it had a ERR_UNKNOWN_URL_SCHEME error.

Adding target="_blank", as suggested by this discussion of the issue fixed the problem for me.

Use images instead of radio buttons

Example:

Heads up! This solution is CSS-only.

Credit-card selector, the MasterCard on the modded demo is hovered.

I recommend you take advantage of CSS3 to do that, by hidding the by-default input radio button with CSS3 rules:

.options input{
    margin:0;padding:0;
    -webkit-appearance:none;
       -moz-appearance:none;
            appearance:none;
}

I just make an example a few days ago.

What does it mean if a Python object is "subscriptable" or not?

Off the top of my head, the following are the only built-ins that are subscriptable:

string:  "foobar"[3] == "b"
tuple:   (1,2,3,4)[3] == 4
list:    [1,2,3,4][3] == 4
dict:    {"a":1, "b":2, "c":3}["c"] == 3

But mipadi's answer is correct - any class that implements __getitem__ is subscriptable

How do you extract IP addresses from files using a regex in a linux shell?

If you are not given a specific file and you need to extract IP address then we need to do it recursively. grep command -> Searches a text or file for matching a given string and displays the matched string .

grep -roE '[0-9]{1,3}\.[0-9]{1,3}\.[0-9]{1,3}\.[0-9]{1,3}' | grep -oE '[0-9]{1,3}\.[0-9]{1,3}\.[0-9]{1,3}\.[0-9]{1,3}'

-r We can search the entire directory tree i.e. the current directory and all levels of sub-directories. It denotes recursive searching.

-o Print only the matching string

-E Use extended regular expression

If we would not have used the second grep command after the pipe we would have got the IP address along with the path where it is present

How do you force a makefile to rebuild a target

This simple technique will allow the makefile to function normally when forcing is not desired. Create a new target called force at the end of your makefile. The force target will touch a file that your default target depends on. In the example below, I have added touch myprogram.cpp. I also added a recursive call to make. This will cause the default target to get made every time you type make force.

yourProgram: yourProgram.cpp
       g++ -o yourProgram yourProgram.cpp 

force:
       touch yourProgram.cpp
       make

Converting char* to float or double

You are missing an include : #include <stdlib.h>, so GCC creates an implicit declaration of atof and atod, leading to garbage values.

And the format specifier for double is %f, not %d (that is for integers).

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

int main()
{
  char *test = "12.11";
  double temp = strtod(test,NULL);
  float ftemp = atof(test);
  printf("price: %f, %f",temp,ftemp);
  return 0;
}
/* Output */
price: 12.110000, 12.110000

How to set default font family in React Native?

Add

"rnpm": {
  "assets": [
 "./assets/fonts/"
  ]
}

in package.json then run react-native link

Foreach loop, determine which is the last iteration of the loop

As Chris shows, Linq will work; just use Last() to get a reference to the last one in the enumerable, and as long as you aren't working with that reference then do your normal code, but if you ARE working with that reference then do your extra thing. Its downside is that it will always be O(N)-complexity.

You can instead use Count() (which is O(1) if the IEnumerable is also an ICollection; this is true for most of the common built-in IEnumerables), and hybrid your foreach with a counter:

var i=0;
var count = Model.Results.Count();
foreach (Item result in Model.Results)
{
    if (++i == count) //this is the last item
}

Annotation @Transactional. How to rollback?

Just throw any RuntimeException from a method marked as @Transactional.

By default all RuntimeExceptions rollback transaction whereas checked exceptions don't. This is an EJB legacy. You can configure this by using rollbackFor() and noRollbackFor() annotation parameters:

@Transactional(rollbackFor=Exception.class)

This will rollback transaction after throwing any exception.

How to define an empty object in PHP

You can also get an empty object by parsing JSON:

$blankObject= json_decode('{}');

Laravel Redirect Back with() Message

Laravel 5.6.*

Controller

if(true) {
   $msg = [
        'message' => 'Some Message!',
       ];

   return redirect()->route('home')->with($msg);
} else {
  $msg = [
       'error' => 'Some error!',
  ];
  return redirect()->route('welcome')->with($msg);
}

Blade Template

  @if (Session::has('message'))
       <div class="alert alert-success" role="alert">
           {{Session::get('message')}}
       </div>
  @elseif (Session::has('error'))
       <div class="alert alert-warning" role="alert">
           {{Session::get('error')}}
       </div>
  @endif

Enyoj

jQuery AutoComplete Trigger Change Event

The programmatically trigger to call the autocomplete.change event is via a namespaced trigger on the source select element.

$("#CompanyList").trigger("blur.autocomplete");

Within version 1.8 of jquery UI..

.bind( "blur.autocomplete", function( event ) {
    if ( self.options.disabled ) {
        return;
    }

    clearTimeout( self.searching );
    // clicks on the menu (or a button to trigger a search) will cause a blur event
    self.closing = setTimeout(function() {
        self.close( event );
        self._change( event );
    }, 150 );
});

Colon (:) in Python list index

a[len(a):] - This gets you the length of a to the end. It selects a range. If you reverse a[:len(a)] it will get you the beginning to whatever is len(a).

How to create a video from images with FFmpeg?

Simple Version from the Docs

Works particularly great for Google Earth Studio images:

ffmpeg -framerate 24 -i Project%03d.png Project.mp4

Center button under form in bootstrap

Try adding this class

class="pager"

<p class="pager" style="line-height: 70px;">
    <button type="submit" class="btn">Confirm</button>
</p>

I tried mine within a <div class=pager><button etc etc></div> which worked well

See http://getbootstrap.com/components/ look under Pagination -> Pager

This looks like the correct bootstrap class to center this, text-align: center; is meant for text not images and blocks etc.

How to set JAVA_HOME in Mac permanently?

run this command on your terminal(here -v11 is for version 11(java11))-:

/usr/libexec/java_home -v11

you will get the path on your terminal something like this -:

/Library/Java/JavaVirtualMachines/jdk-11.0.9.jdk/Contents/Home

now you need to open your bash profile in any editor for eg VS Code

if you want to edit your bash_profile in vs code then run this command -:

code ~/.bash_profile

else run this command and then press i to insert the path. -:

open ~/.bash_profile

you will get your .bash_profile now you need to add the path so add this in .bash_profile (path which you get from 1st command)-:

export JAVA_HOME=/Library/Java/JavaVirtualMachines/jdk-11.0.9.jdk/Contents/Home

if you were using code editor then now go to terminal and run this command to save the changes -:

source ~/.bash_profile

else press esc then :wq to exit from bash_profile then go to terminal and run the command given above. process completed. now you can check using this command -:

echo $JAVA_HOME

you will get/Library/Java/JavaVirtualMachines/jdk-11.0.9.jdk/Contents/Home

bs4.FeatureNotFound: Couldn't find a tree builder with the features you requested: lxml. Do you need to install a parser library?

Actually 3 of the options mentioned by other work.

1.

soup_object= BeautifulSoup(markup,"html.parser") #Python HTML parser
pip install lxml

soup_object= BeautifulSoup(markup,'lxml') # C dependent parser 
pip install html5lib

soup_object= BeautifulSoup(markup,'html5lib') # C dependent parser 

How to change column datatype in SQL database without losing data

Why do you think you will lose data? Simply go into Management Studio and change the data type. If the existing value can be converted to bool (bit), it will do that. In other words, if "1" maps to true and "0" maps to false in your original field, you'll be fine.

How to programmatically set the Image source

Try this:

BitmapImage image = new BitmapImage(new Uri("/MyProject;component/Images/down.png", UriKind.Relative));

Removing black dots from li and ul

Relatable post

Those pesky black dots you are referencing to are called bullets.

They are pretty simple to remove, just add this line to your css:

ul {
    list-style-type: none;
}

Hope this helps

Using OpenGl with C#?

Concerning the (somewhat off topic I know but since it was brought up earlier) XNA vs OpenGL choice, it might be beneficial in several cases to go with OpenGL instead of XNA (and in other XNA instead of OpenGL...).

If you are going to run the applications on Linux or Mac using Mono, it might be a good choice to go with OpenGL. Also, which isn't so widely known I think, if you have customers that are going to run your applications in a Citrix environment, then DirectX/Direct3D/XNA won't be as economical a choice as OpenGL. The reason for this is that OpenGL applications can be co-hosted on a lesser number of servers (due to performance issues a single server cannot host an infinite number of application instances) than DirectX/XNA applications which demands dedicated virtual servers to run in hardware accelerated mode. Other requirements exists like supported graphics cards etc but I will keep to the XNA vs OpenGL issue. As an IT Architect, Software developer etc this will have to be considered before choosing between OpenGL and DirectX/XNA...

A side note is that WebGL is based on OpenGL ES3 afaik...

As a further note, these are not the only considerations, but they might make the choice easier for some...

Running code in main thread from another thread

A condensed code block is as follows:

   new Handler(Looper.getMainLooper()).post(new Runnable() {
       @Override
       public void run() {
           // things to do on the main thread
       }
   });

This does not involve passing down the Activity reference or the Application reference.

Kotlin Equivalent:

    Handler(Looper.getMainLooper()).post(Runnable {
        // things to do on the main thread
    })

Cannot obtain value of local or argument as it is not available at this instruction pointer, possibly because it has been optimized away

Also In VS 2015 Community Edition

go to Debug->Options or Tools->Options

and check Debugging->General->Suppress JIT optimization on module load (Managed only)

How to add buttons like refresh and search in ToolBar in Android?

OK, I got the icons because I wrote in menu.xml android:showAsAction="ifRoom" instead of app:showAsAction="ifRoom" since i am using v7 library.

However the title is coming at center of extended toolbar. How to make it appear at the top?

Verifying a specific parameter with Moq

Had one of these as well, but the parameter of the action was an interface with no public properties. Ended up using It.Is() with a seperate method and within this method had to do some mocking of the interface

public interface IQuery
{
    IQuery SetSomeFields(string info);
}

void DoSomeQuerying(Action<IQuery> queryThing);

mockedObject.Setup(m => m.DoSomeQuerying(It.Is<Action<IQuery>>(q => MyCheckingMethod(q)));

private bool MyCheckingMethod(Action<IQuery> queryAction)
{
    var mockQuery = new Mock<IQuery>();
    mockQuery.Setup(m => m.SetSomeFields(It.Is<string>(s => s.MeetsSomeCondition())
    queryAction.Invoke(mockQuery.Object);
    mockQuery.Verify(m => m.SetSomeFields(It.Is<string>(s => s.MeetsSomeCondition(), Times.Once)
    return true
}

How do I convert a String to a BigInteger?

Instead of using valueOf(long) and parse(), you can directly use the BigInteger constructor that takes a string argument:

BigInteger numBig = new BigInteger("8599825996872482982482982252524684268426846846846846849848418418414141841841984219848941984218942894298421984286289228927948728929829");

That should give you the desired value.

WRONGTYPE Operation against a key holding the wrong kind of value php

Redis supports 5 data types. You need to know what type of value that a key maps to, as for each data type, the command to retrieve it is different.

Here are the commands to retrieve key value:

  • if value is of type string -> GET <key>
  • if value is of type hash -> HGETALL <key>
  • if value is of type lists -> lrange <key> <start> <end>
  • if value is of type sets -> smembers <key>
  • if value is of type sorted sets -> ZRANGEBYSCORE <key> <min> <max>

Use the TYPE command to check the type of value a key is mapping to:

  • type <key>

Delete all rows in table

I would suggest using TRUNCATE TABLE, it's quicker and uses less resources than DELETE FROM xxx

Here's the related MSDN article

'git status' shows changed files, but 'git diff' doesn't

Short Answer

Running git add sometimes helps.

Example

Git status is showing changed files and git diff is showing nothing...

> git status
On branch master
Changes not staged for commit:
  (use "git add <file>..." to update what will be committed)
  (use "git checkout -- <file>..." to discard changes in working directory)

        modified:   package.json

no changes added to commit (use "git add" and/or "git commit -a")
> git diff
> 

...running git add resolves the inconsistency.

> git add
> git status
On branch master
nothing to commit, working directory clean
> 

Indent List in HTML and CSS

You can also use html to override the css locally. I was having a similar issue and this worked for me:

<html>
<body>

<h4>A nested List:</h4>
<ul style="PADDING-LEFT: 12px">
  <li>Coffee</li>
  <li>Tea
    <ul>
    <li>Black tea</li>
    <li>Green tea</li>
    </ul>
  </li>
  <li>Milk</li>
</ul>

</body>
</html>

Git/GitHub can't push to master

Mark Longair's solution using git remote set-url... is quite clear. You can also get the same behavior by directly editing this section of the .git/config file:

before:

[remote "origin"]
    fetch = +refs/heads/*:refs/remotes/origin/*
    url = git://github.com/my_user_name/my_repo.git

after:

[remote "origin"]
    fetch = +refs/heads/*:refs/remotes/origin/*
    url = [email protected]:my_user_name/my_repo.git

(And conversely, the git remote set-url... invocation produces the above change.)

How can I convert JSON to a HashMap using Gson?

This is more of addendum to Kevin Dolan's answer than a complete answer, but I was having trouble extracting the type from the Number. This is my solution:

private Object handlePrimitive(JsonPrimitive json) {
  if(json.isBoolean()) {
    return json.getAsBoolean();
  } else if(json.isString())
    return json.getAsString();
  }

  Number num = element.getAsNumber();

  if(num instanceof Integer){
    map.put(fieldName, num.intValue());
  } else if(num instanceof Long){
    map.put(fieldName, num.longValue());
  } else if(num instanceof Float){
    map.put(fieldName, num.floatValue());
  } else {    // Double
     map.put(fieldName, num.doubleValue());
  }
}

How do I run Java .class files?

This can mean a lot of things, but the most common one is that the class contained in the file doesn't have the same name as the file itself. So, check if your class is also called HelloWorld2.

Should you use .htm or .html file extension? What is the difference, and which file is correct?

In short, they are exactly the same. If you notice the end of the URL, sometimes you'll see .htm and other times you'll see .html. It still refers to the Hyper-Text Markup Language.

What does a (+) sign mean in an Oracle SQL WHERE clause?

This is an Oracle-specific notation for an outer join. It means that it will include all rows from t1, and use NULLS in the t0 columns if there is no corresponding row in t0.

In standard SQL one would write:

SELECT t0.foo, t1.bar
  FROM FIRST_TABLE t0
 RIGHT OUTER JOIN SECOND_TABLE t1;

Oracle recommends not to use those joins anymore if your version supports ANSI joins (LEFT/RIGHT JOIN) :

Oracle recommends that you use the FROM clause OUTER JOIN syntax rather than the Oracle join operator. Outer join queries that use the Oracle join operator (+) are subject to the following rules and restrictions […]

Preloading @font-face fonts?

Recently I was working on a game compatible with CocoonJS with DOM limited to the canvas element - here is my approach:

Using fillText with a font that has not been loaded yet will execute properly but with no visual feedback - so the canvas plane will stay intact - all you have to do is periodically check the canvas for any changes (for example looping through getImageData searching for any non transparent pixel) that will happen when the font loads properly.

I have explained this technique a little bit more in my recent article http://rezoner.net/preloading-font-face-using-canvas,686

How do I include a JavaScript file in another JavaScript file?

So this is a edge case. But if you need to load the JavaScript from a remote source, most modern browsers might block your cross-site requests due to CORS or something similar. So normal

<script src="https://another-domain.com/example.js"></script>

Won't work. And doing the document.createElement('script').src = '...' won't cut it either. Instead, what you could do is load the java-script as a resource via standard GET request, and do this:

<script type="text/javascript">
    var script = document.createElement('script');
    script.type = 'text/javascript';

    let xhr = new XMLHttpRequest();
    xhr.open("GET", 'https://raw.githubusercontent.com/Torxed/slimWebSocket/master/slimWebSocket.js', true);
    xhr.onreadystatechange = function() {
        if (this.readyState === XMLHttpRequest.DONE && this.status === 200) {
            script.innerHTML = this.responseText; // <-- This one
            document.head.appendChild(script);
        }
    }
    xhr.send();
</script>

By grabbing the content yourself, the browser won't notice malicious intents and allow you go do the request. Then you add it in <script>'s innerHTML instead. This still causes the browser (at least tested in Chrome) to parse/execute the script.

Again, this is a edge case use case. And you'll have no backwards compatibility or browser compliance probably. But fun/useful thing to know about.

SecurityException during executing jnlp file (Missing required Permissions manifest attribute in main jar)

JAR File Manifest Attributes for Security

The JAR file manifest contains information about the contents of the JAR file, including security and configuration information.

Add the attributes to the manifest before the JAR file is signed.
See Modifying a Manifest File in the Java Tutorial for information on adding attributes to the JAR manifest file.

Permissions Attribute

The Permissions attribute is used to verify that the permissions level requested by the RIA when it runs matches the permissions level that was set when the JAR file was created.

Use this attribute to help prevent someone from re-deploying an application that is signed with your certificate and running it at a different privilege level. Set this attribute to one of the following values:

  • sandbox - runs in the security sandbox and does not require additional permissions.

  • all-permissions - requires access to the user's system resources.

Changes to Security Slider:

The following changes to Security Slider were included in this release(7u51):

  • Block Self-Signed and Unsigned applets on High Security Setting
  • Require Permissions Attribute for High Security Setting
  • Warn users of missing Permissions Attributes for Medium Security Setting

For more information, see Java Control Panel documentation.

enter image description here

sample MANIFEST.MF

Manifest-Version: 1.0
Ant-Version: Apache Ant 1.8.3
Created-By: 1.7.0_51-b13 (Oracle Corporation)
Trusted-Only: true
Class-Path: lib/plugin.jar
Permissions: sandbox
Codebase: http://myweb.de http://www.myweb.de
Application-Name: summary-applet

Variable length (Dynamic) Arrays in Java

Arrays in Java are of fixed size. What you'd need is an ArrayList, one of a number of extremely valuable Collections available in Java.

Instead of

Integer[] ints = new Integer[x]

you use

List<Integer> ints = new ArrayList<Integer>();

Then to change the list you use ints.add(y) and ints.remove(z) amongst many other handy methods you can find in the appropriate Javadocs.

I strongly recommend studying the Collections classes available in Java as they are very powerful and give you a lot of builtin functionality that Java-newbies tend to try to rewrite themselves unnecessarily.

Converting a year from 4 digit to 2 digit and back again in C#

Even if a builtin way existed, it wouldn't validate it as greater than today and it would differ very little from a substring call. I wouldn't worry about it.

How do I fix the error "Only one usage of each socket address (protocol/network address/port) is normally permitted"?

I faced similar problem on windows server 2012 STD 64 bit , my problem is resolved after updating windows with all available windows updates.

Does the Java &= operator apply & or &&?

Here's a simple way to test it:

public class OperatorTest {     
    public static void main(String[] args) {
        boolean a = false;
        a &= b();
    }

    private static boolean b() {
        System.out.println("b() was called");
        return true;
    }
}

The output is b() was called, therefore the right-hand operand is evaluated.

So, as already mentioned by others, a &= b is the same as a = a & b.

Replace words in the body text

I ended up with this function to safely replace text without side effects (so far):

function replaceInText(element, pattern, replacement) {
    for (let node of element.childNodes) {
        switch (node.nodeType) {
            case Node.ELEMENT_NODE:
                replaceInText(node, pattern, replacement);
                break;
            case Node.TEXT_NODE:
                node.textContent = node.textContent.replace(pattern, replacement);
                break;
            case Node.DOCUMENT_NODE:
                replaceInText(node, pattern, replacement);
        }
    }
}

It's for cases where the 16kB of findAndReplaceDOMText are a bit too heavy.

Get last key-value pair in PHP array

"SPL-way":

$splArray = SplFixedArray::fromArray($array);
$last_item_with_preserved_index[$splArray->getSize()-1] = $splArray->offsetGet($splArray->getSize()-1);

Read more about SplFixedArray and why it's in some cases ( especially with big-index sizes array-data) more preferable than basic array here => The SplFixedArray class.

Php header location redirect not working

Make Sure that you don't leave a space before <?php when you start <?php tag at the top of the page.

How to export data from Spark SQL to CSV

Since Spark 2.X spark-csv is integrated as native datasource. Therefore, the necessary statement simplifies to (windows)

df.write
  .option("header", "true")
  .csv("file:///C:/out.csv")

or UNIX

df.write
  .option("header", "true")
  .csv("/var/out.csv")

Notice: as the comments say, it is creating the directory by that name with the partitions in it, not a standard CSV file. This, however, is most likely what you want since otherwise your either crashing your driver (out of RAM) or you could be working with a non distributed environment.

How to get array keys in Javascript?

The question is pretty old, but nowadays you can use forEach, which is efficient and will retain the keys as numbers:

let keys = widthRange.map((v,k) => k).filter(i=>i!==undefined))

This loops through widthRange and makes a new array with the value of the keys, and then filters out all sparce slots by only taking the values that are defined.

(Bad idea, but for thorughness: If slot 0 was always empty, that could be shortened to filter(i=>i) or filter(Boolean)

And, it may be less efficient, but the numbers can be cast with let keys = Object.keys(array).map(i=>i*1)

How to solve "The directory is not empty" error when running rmdir command in a batch script?

I just encountered the same problem and it had to do with some files being lost or corrupted. To correct the issue, just run check disk:

chkdsk /F e:

This can be run from the search windows box or from a cmd prompt. The /F fixes any issues it finds, like recovering the files. Once this finishes running, you can delete the files and folders like normal.

SSRS Conditional Formatting Switch or IIF

To dynamically change the color of a text box goto properties, goto font/Color and set the following expression

=SWITCH(Fields!CurrentRiskLevel.Value = "Low", "Green",
Fields!CurrentRiskLevel.Value = "Moderate", "Blue",
Fields!CurrentRiskLevel.Value = "Medium", "Yellow",
Fields!CurrentRiskLevel.Value = "High", "Orange",
Fields!CurrentRiskLevel.Value = "Very High", "Red"
)

Same way for tolerance

=SWITCH(Fields!Tolerance.Value = "Low", "Red",
Fields!Tolerance.Value = "Moderate", "Orange",
Fields!Tolerance.Value = "Medium", "Yellow",
Fields!Tolerance.Value = "High", "Blue",
Fields!Tolerance.Value = "Very High", "Green")

PHP How to find the time elapsed since a date time?

One option that'll work with any version of PHP is to do what's already been suggested, which is something like this:

$eventTime = '2010-04-28 17:25:43';
$age = time() - strtotime($eventTime);

That will give you the age in seconds. From there, you can display it however you wish.

One problem with this approach, however, is that it won't take into account time shifts causes by DST. If that's not a concern, then go for it. Otherwise, you'll probably want to use the diff() method in the DateTime class. Unfortunately, this is only an option if you're on at least PHP 5.3.

Efficient Algorithm for Bit Reversal (from MSB->LSB to LSB->MSB) in C

Bit reversal in pseudo code

source -> byte to be reversed b00101100 destination -> reversed, also needs to be of unsigned type so sign bit is not propogated down

copy into temp so original is unaffected, also needs to be of unsigned type so that sign bit is not shifted in automaticaly

bytecopy = b0010110

LOOP8: //do this 8 times test if bytecopy is < 0 (negative)

    set bit8 (msb) of reversed = reversed | b10000000 

else do not set bit8

shift bytecopy left 1 place
bytecopy = bytecopy << 1 = b0101100 result

shift result right 1 place
reversed = reversed >> 1 = b00000000
8 times no then up^ LOOP8
8 times yes then done.

How Can I Override Style Info from a CSS Class in the Body of a Page?

  • Id's are prior to classnames.
  • Tag attribue 'style=' is prior to CSS selectors.
  • !important word is prior to first two rules.
  • More specific CSS selectors are prior to less specific. More specific will be applied.

for example:

  • .divclass .spanclass is more specific than .spanclass
  • .divclass.divclass is more specific than .divclass
  • #divId .spanclass has ID that's why it is more specific than .divClass .spanClass
  • <div id="someDiv" style="color:red;"> has attribute and beats #someDiv{color:blue}
  • style: #someDiv{color:blue!important} will be applied over attribute style="color:red"

How to support different screen size in android

Beginning with Android 3.2 (API level 13), size groups (folders small, normal, large, xlarge) are deprecated in favor of a new technique for managing screen sizes based on the available screen width.



There are different resource configurations that you can specify based on the space available for your layout:

1) Smallest Width - The fundamental size of a screen, as indicated by the shortest dimension of the available screen area.

Qualifier Value: sw'dp value'dp

Eg. res/sw600dp/layout.xml -> will be used for all screen sizes bigger or equal to 600dp. This does not take the device orientation into account.


2) Available Screen Width - Specifies a minimum available width in dp units at which the resources should be used.

Qualifier Value: w'dp value'dp

Eg. res/w600dp/layout.xml -> will be used for all screens, which width is greater than or equal to 600dp.


3) Available Screen Height - Specifies a minimum screen height in dp units at which the resources should be used.

Qualifier Value: h'dp value'dp

Eg. res/h600dp/layout.xml -> will be used for all screens, which height is greater than or equal to 600dp.



So at the end your folder structure might look like this:

res/layout/layout.xml -> for handsets (smaller than 600dp available width)
res/layout-sw600dp/layout.xml -> for 7” tablets (600dp wide and bigger)
res/layout-sw720dp/layout.xml -> for 10” tablets (720dp wide and bigger)


For more information please read the official documentation:
https://developer.android.com/guide/practices/screens_support.html#DeclaringTabletLayouts

How do I create my own URL protocol? (e.g. so://...)

You don't really have to do any registering as such. I've seen many programs, like emule, create their own protocol specificier (that's what I think it's called). After that, you basically just have to set some values in the registry as to what program handles that protocol. I'm not sure if there's any official registry of protocol specifiers. There isn't really much to stop you from creating your own protocol specifier for your own application if you want people to open your app from their browser.

Why does an onclick property set with setAttribute fail to work in IE?

Not relevant to the onclick issue, but also related:

For html attributes whose name collide with javascript reserved words, an alternate name is chosen, eg. <div class=''>, but div.className, or <label for='...'>, but label.htmlFor.

In reasonable browsers, this doesn't affect setAttribute. So in gecko and webkit you'd call div.setAttribute('class', 'foo'), but in IE you have to use the javascript property name instead, so div.setAttribute('className', 'foo').

How to convert List<string> to List<int>?

  public List<int> ConvertStringListToIntList(List<string> list) 
  {
     List<int> resultList = new List<int>();
     for (int i = 0; i < list.Count; i++)
        resultList.Add(Convert.ToInt32(list[i]));

     return resultList;
  }

How do you run a crontab in Cygwin on Windows?

The correct syntax to install cron in cygwin as Windows service is to pass -n as argument and not -D:

cygrunsrv --install cron --path /usr/sbin/cron --args -n

-D returns usage error when starting cron in cygwin:

$

$cygrunsrv --install cron --path /usr/sbin/cron --args -D

$cygrunsrv --start cron

cygrunsrv: Error starting a service: QueryServiceStatus: Win32 error 1062:

The service has not been started.

$cat /var/log/cron.log

cron: unknown option -- D

usage: /usr/sbin/cron [-n] [-x [ext,sch,proc,parc,load,misc,test,bit]]

$

Below page has a good explanation.

Installing & Configuring the Cygwin Cron Service in Windows: https://www.davidjnice.com/cygwin_cron_service.html

P.S. I had to run Cygwin64 Terminal on my Windows 10 PC as administrator in order to install cron as Windows service.

Excel: Use a cell value as a parameter for a SQL query

The SQL is somewhat like the syntax of MS SQL.

SELECT * FROM [table$] WHERE *;

It is important that the table name is ended with a $ sign and the whole thing is put into brackets. As conditions you can use any value, but so far Excel didn't allow me to use what I call "SQL Apostrophes" (´), so a column title in one word is recommended.

If you have users listed in a table called "Users", and the id is in a column titled "id" and the name in a column titled "Name", your query will look like this:

SELECT Name FROM [Users$] WHERE id = 1;

Hope this helps.

Regex to Match Symbols: !$%^&*()_+|~-=`{}[]:";'<>?,./

The most simple and shortest way to accomplish this:

/[^\p{L}\d\s@#]/u

Explanation

[^...] Match a single character not present in the list below

  • \p{L} => matches any kind of letter from any language

  • \d => matches a digit zero through nine

  • \s => matches any kind of invisible character

  • @# => @ and # characters

Don't forget to pass the u (unicode) flag.

How to map a composite key with JPA and Hibernate?

Looks like you are doing this from scratch. Try using available reverse engineering tools like Netbeans Entities from Database to at least get the basics automated (like embedded ids). This can become a huge headache if you have many tables. I suggest avoid reinventing the wheel and use as many tools available as possible to reduce coding to the minimum and most important part, what you intent to do.

How do I use tools:overrideLibrary in a build.gradle file?

As library requires minSdkVersion 17 then you can change the same in build.gradle(Module:Application) file:

defaultConfig {
        minSdkVersion 17 
        targetSdkVersion 25
}

and after that building the project should not throw any build error.

Getting Current time to display in Label. VB.net

Use Date.Now instead of DateTime.Now

How to add a custom button to the toolbar that calls a JavaScript function?

You can add the button image as follows:

CKEDITOR.plugins.add('showtime',   //name of our plugin
{    
    requires: ['dialog'], //requires a dialog window
    init:function(a) {
  var b="showtime";
  var c=a.addCommand(b,new CKEDITOR.dialogCommand(b));
  c.modes={wysiwyg:1,source:1}; //Enable our plugin in both modes
  c.canUndo=true;
 
  //add new button to the editor
  a.ui.addButton("showtime",
  {
   label:'Show current time',
   command:b,
   icon:this.path+"showtime.png"   //path of the icon
  });
  CKEDITOR.dialog.add(b,this.path+"dialogs/ab.js") //path of our dialog file
 }
});

Here is the actual plugin with all steps described.

How to create a user in Django?

The correct way to create a user in Django is to use the create_user function. This will handle the hashing of the password, etc..

from django.contrib.auth.models import User
user = User.objects.create_user(username='john',
                                 email='[email protected]',
                                 password='glass onion')

Is there a way to 'pretty' print MongoDB shell output to a file?

Using print and JSON.stringify you can simply produce a valid JSON result.
Use --quiet flag to filter shell noise from the output.
Use --norc flag to avoid .mongorc.js evaluation. (I had to do it because of a pretty-formatter that I use, which produces invalid JSON output) Use DBQuery.shellBatchSize = ? replacing ? with the limit of the actual result to avoid paging.

And finally, use tee to pipe the terminal output to a file:

// Shell:
mongo --quiet --norc ./query.js | tee ~/my_output.json

// query.js:
DBQuery.shellBatchSize = 2000;
function toPrint(data) {
  print(JSON.stringify(data, null, 2));
}

toPrint(
  db.getCollection('myCollection').find().toArray()
);

Hope this helps!

Warning: mysqli_query() expects parameter 1 to be mysqli, resource given

You are using improper syntax. If you read the docs mysqli_query() you will find that it needs two parameter.

mixed mysqli_query ( mysqli $link , string $query [, int $resultmode = MYSQLI_STORE_RESULT ] )

mysql $link generally means, the resource object of the established mysqli connection to query the database.

So there are two ways of solving this problem

mysqli_query();

$myConnection= mysqli_connect("$db_host","$db_username","$db_pass", "mrmagicadam") or die ("could not connect to mysql"); 
$sqlCommand="SELECT id, linklabel FROM pages ORDER BY pageorder ASC";
$query=mysqli_query($myConnection, $sqlCommand) or die(mysqli_error($myConnection));

Or, Using mysql_query() (This is now obselete)

$myConnection= mysql_connect("$db_host","$db_username","$db_pass") or die ("could not connect to mysql");
mysql_select_db("mrmagicadam") or die ("no database");        
$sqlCommand="SELECT id, linklabel FROM pages ORDER BY pageorder ASC";
$query=mysql_query($sqlCommand) or die(mysql_error());

As pointed out in the comments, be aware of using die to just get the error. It might inadvertently give the viewer some sensitive information .

A free tool to check C/C++ source code against a set of coding standards?

The only tool I know is Vera. Haven't used it, though, so can't comment how viable it is. Demo looks promising.

How to differ sessions in browser-tabs?

You can use link-rewriting to append a unique identifier to all your URLs when starting at a single page (e.g. index.html/jsp/whatever). The browser will use the same cookies for all your tabs so everything you put in cookies will not be unique.

Excel: Searching for multiple terms in a cell

In addition to the answer of @teylyn, I would like to add that you can put the string of multiple search terms inside a SINGLE cell (as opposed to using a different cell for each term and then using that range as argument to SEARCH), using named ranges and the EVALUATE function as I found from this link.

For example, I put the following terms as text in a cell, $G$1:

"PRB", "utilization", "alignment", "spectrum"

Then, I defined a named range named search_terms for that cell as described in the link above and shown in the figure below:

Named range definition

In the Refers to: field I put the following:

=EVALUATE("{" & TDoc_List!$G$1 & "}")

The above EVALUATE expression is simple used to emulate the literal string

{"PRB", "utilization", "alignment", "spectrum"}

to be used as input to the SEARCH function: using a direct reference to the SINGLE cell $G$1 (augmented with the curly braces in that case) inside SEARCH does not work, hence the use of named ranges and EVALUATE.

The trick now consists in replacing the direct reference to $G$1 by the EVALUATE-augmented named range search_terms.

The formula

It really works, and shows once more how powerful Excel really is!

It really works!

Hope this helps.

Create Pandas DataFrame from a string

A quick and easy solution for interactive work is to copy-and-paste the text by loading the data from the clipboard.

Select the content of the string with your mouse:

Copy data for pasting into a Pandas dataframe

In the Python shell use read_clipboard()

>>> pd.read_clipboard()
  col1;col2;col3
0       1;4.4;99
1      2;4.5;200
2       3;4.7;65
3      4;3.2;140

Use the appropriate separator:

>>> pd.read_clipboard(sep=';')
   col1  col2  col3
0     1   4.4    99
1     2   4.5   200
2     3   4.7    65
3     4   3.2   140

>>> df = pd.read_clipboard(sep=';') # save to dataframe

How can I submit form on button click when using preventDefault()?

Replace this :

$('#subscription_order_form').submit(function(e){
  e.preventDefault();
});

with this:

$('#subscription_order_form').on('keydown', function(e){
    if (e.which===13) e.preventDefault();
});

FIDDLE

That will prevent the form from submitting when Enter key is pressed as it prevents the default action of the key, but the form will submit normally on click.

Disable scrolling in all mobile devices

The CSS property touch-action may get you what you are looking for, though it may not work in all your target browsers.

html, body {
    width: 100%; height: 100%;
    overflow: hidden;
    touch-action: none;
}

ImportError: DLL load failed: %1 is not a valid Win32 application. But the DLL's are there

I experienced the same problem while trying to write a code concerning Speech_to_Text.

The solution was very simple. Uninstall the previous pywin32 using the pip method

pip uninstall pywin32

The above will remove the existing one which is by default for 32 bit computers. And install it again using

pip install pywin32

This will install the one for the 64 bit computer which you are using.

appcompat-v7:21.0.0': No resource found that matches the given name: attr 'android:actionModeShareDrawable'

Upgrading to latest gradle plugin solve my problem :

classpath 'com.android.tools.build:gradle:0.13.+'

Retrieving the output of subprocess.call()

Output from subprocess.call() should only be redirected to files.

You should use subprocess.Popen() instead. Then you can pass subprocess.PIPE for the stderr, stdout, and/or stdin parameters and read from the pipes by using the communicate() method:

from subprocess import Popen, PIPE

p = Popen(['program', 'arg1'], stdin=PIPE, stdout=PIPE, stderr=PIPE)
output, err = p.communicate(b"input data that is passed to subprocess' stdin")
rc = p.returncode

The reasoning is that the file-like object used by subprocess.call() must have a real file descriptor, and thus implement the fileno() method. Just using any file-like object won't do the trick.

See here for more info.

Operation Not Permitted when on root - El Capitan (rootless disabled)

If after calling "csrutil disabled" still your command does not work, try with "sudo" in terminal, for example:

sudo mv geckodriver /usr/local/bin

And it should work.

Finding Android SDK on Mac and adding to PATH

If you don't want to open Android Studio just to modify your path...

They live here with a default installation:

${HOME}/Library/Android/sdk/tools
${HOME}/Library/Android/sdk/platform-tools

Here's what you want to add to your .bashwhatever

export PATH="${HOME}/Library/Android/sdk/tools:${HOME}/Library/Android/sdk/platform-tools:${PATH}"

Set start value for column with autoincrement

Also note that you cannot normally set a value for an IDENTITY column. You can, however, specify the identity of rows if you set IDENTITY_INSERT to ON for your table. For example:

SET IDENTITY_INSERT Orders ON

-- do inserts here

SET IDENTITY_INSERT Orders OFF

This insert will reset the identity to the last inserted value. From MSDN:

If the value inserted is larger than the current identity value for the table, SQL Server automatically uses the new inserted value as the current identity value.

How to solve ADB device unauthorized in Android ADB host device?

  • Get the public key from the client phone (adb host)

    cat /data/.android/adbkey.pub

  • copy the above public key to the target phone's /data/misc/adb/adb_keys location. (you may need to stop the adb daemon first with stop adbd)

    cat /data/misc/adb/adb_keys

verify both cat outputs match.

try restarting adb daemon on target start adbd or just reboot them.

If you are having problems reading or writing to ADB KEYS in above steps, try setting environment variable ADB_KEYS_PATH with a temporary path (eg: /data/local/tmp). Refer to that link it goes into more details

    "On the host, the user public/private key pair is automatically generated,
    if it does not exist, when the adb daemon starts and is stored in
    $HOME/.android/adb_key(.pub) or in $ANDROID_SDK_HOME on windows. If needed,
    the ADB_KEYS_PATH env variable may be set to a :-separated (; under
    Windows) list of private keys, e.g. company-wide or vendor keys.

    On the device, vendors public keys are installed at build time in
    /adb_keys. User-installed keys are stored in /data/misc/adb/adb_keys"

How can I do DNS lookups in Python, including referring to /etc/hosts?

list( map( lambda x: x[4][0], socket.getaddrinfo( \
     'www.example.com.',22,type=socket.SOCK_STREAM)))

gives you a list of the addresses for www.example.com. (ipv4 and ipv6)

Add a row number to result set of a SQL query

So before MySQL 8.0 there is no ROW_NUMBER() function. Accpted answer rewritten to support older versions of MySQL:

SET @row_number = 0;
SELECT t.A, t.B, t.C, (@row_number:=@row_number + 1) AS number
FROM dbo.tableZ AS t ORDER BY t.A;

Angular ng-if="" with multiple arguments

For people looking to do if statements with multiple 'or' values.

<div ng-if="::(a || b || c || d || e || f)"><div>

Spring @Transactional read-only propagation

Calling readOnly=false from readOnly=true doesn't work since the previous transaction continues.

In your example, the handle() method on your service layer is starting a new read-write transaction. If the handle method in turn calls service methods that annotated read-only, the read-only will take no effect as they will participate in the existing read-write transaction instead.

If it is essential for those methods to be read-only, then you can annotate them with Propagation.REQUIRES_NEW, and they will then start a new read-only transaction rather than participate in the existing read-write transaction.

Here is a worked example, CircuitStateRepository is a spring-data JPA repository.

BeanS calls a transactional=read-only Bean1, which does a lookup and calls transactional=read-write Bean2 which saves a new object.

  • Bean1 starts a read-only tx.

31 09:39:44.199 [pool-1-thread-1] DEBUG o.s.orm.jpa.JpaTransactionManager - Creating new transaction with name [nz.co.vodafone.wcim.business.Bean1.startSomething]: PROPAGATION_REQUIRED,ISOLATION_DEFAULT,readOnly; ''

  • Bean 2 pariticipates in it.

    31 09:39:44.230 [pool-1-thread-1] DEBUG o.s.orm.jpa.JpaTransactionManager - Participating in existing transaction

    Nothing is committed to the database.

Now change Bean2 @Transactional annotation to add propagation=Propagation.REQUIRES_NEW

  • Bean1 starts a read-only tx.

    31 09:31:36.418 [pool-1-thread-1] DEBUG o.s.orm.jpa.JpaTransactionManager - Creating new transaction with name [nz.co.vodafone.wcim.business.Bean1.startSomething]: PROPAGATION_REQUIRED,ISOLATION_DEFAULT,readOnly; ''

  • Bean2 starts a new read-write tx

    31 09:31:36.449 [pool-1-thread-1] DEBUG o.s.orm.jpa.JpaTransactionManager - Suspending current transaction, creating new transaction with name [nz.co.vodafone.wcim.business.Bean2.createSomething]

And the changes made by Bean2 are now committed to the database.

Here's the example, tested with spring-data, hibernate and oracle.

@Named
public class BeanS {    
    @Inject
    Bean1 bean1;

    @Scheduled(fixedRate = 20000)
    public void runSomething() {
        bean1.startSomething();
    }
}

@Named
@Transactional(readOnly = true)
public class Bean1 {    
    Logger log = LoggerFactory.getLogger(Bean1.class);

    @Inject
    private CircuitStateRepository csr;

    @Inject
    private Bean2 bean2;

    public void startSomething() {    
        Iterable<CircuitState> s = csr.findAll();
        CircuitState c = s.iterator().next();
        log.info("GOT CIRCUIT {}", c.getCircuitId());
        bean2.createSomething(c.getCircuitId());    
    }
}

@Named
@Transactional(readOnly = false)
public class Bean2 {    
    @Inject
    CircuitStateRepository csr;

    public void createSomething(String circuitId) {
        CircuitState c = new CircuitState(circuitId + "-New-" + new DateTime().toString("hhmmss"), new DateTime());

        csr.save(c);
     }
}

How do I download/extract font from chrome developers tools?

It's easy (For Chorme only)

  1. Right click > inspect element
  2. Go to 'Resources' tab and find 'Fonts' in dropdown folders
    • 'Resouces' tab may be called 'Application'
  3. Right click on font (in .woff format) > open link in new tab (this should download the font in .woff format
  4. Find a 'Woff to TTf or Otf' font converter online
  5. Enjoy after conversion!

How do I wait until Task is finished in C#?

It waits for client.GetAsync("aaaaa");, but doesn't wait for result = Print(x)

Try responseTask.ContinueWith(x => result = Print(x)).Wait()

--EDIT--

Task responseTask = Task.Run(() => { 
    Thread.Sleep(1000); 
    Console.WriteLine("In task"); 
});
responseTask.ContinueWith(t=>Console.WriteLine("In ContinueWith"));
responseTask.Wait();
Console.WriteLine("End");

Above code doesn't guarantee the output:

In task
In ContinueWith
End

But this does (see the newTask)

Task responseTask = Task.Run(() => { 
    Thread.Sleep(1000); 
    Console.WriteLine("In task"); 
});
Task newTask = responseTask.ContinueWith(t=>Console.WriteLine("In ContinueWith"));
newTask.Wait();
Console.WriteLine("End");

Does React Native styles support gradients?

Here is a good choice for gradients for both platforms iOS and Android:

https://github.com/react-native-community/react-native-linear-gradient

There are others approaches like expo, however react-native-linear-gradient have worked better for me.

<LinearGradient colors={['#4c669f', '#3b5998', '#192f6a']} style={styles.linearGradient}>
  <Text style={styles.buttonText}>
    Sign in with Facebook
  </Text>
</LinearGradient>

// Later on in your styles..
var styles = StyleSheet.create({
  linearGradient: {
    flex: 1,
    paddingLeft: 15,
    paddingRight: 15,
    borderRadius: 5
  },
  buttonText: {
    fontSize: 18,
    fontFamily: 'Gill Sans',
    textAlign: 'center',
    margin: 10,
    color: '#ffffff',
    backgroundColor: 'transparent',
  },
});

How to convert int to QString?

If you need locale-aware number formatting, use QLocale::toString instead.

Creating Threads in python

You can use the target argument in the Thread constructor to directly pass in a function that gets called instead of run.

What's wrong with using == to compare floats in Java?

The following automatically uses the best precision:

/**
 * Compare to floats for (almost) equality. Will check whether they are
 * at most 5 ULP apart.
 */
public static boolean isFloatingEqual(float v1, float v2) {
    if (v1 == v2)
        return true;
    float absoluteDifference = Math.abs(v1 - v2);
    float maxUlp = Math.max(Math.ulp(v1), Math.ulp(v2));
    return absoluteDifference < 5 * maxUlp;
}

Of course, you might choose more or less than 5 ULPs (‘unit in the last place’).

If you’re into the Apache Commons library, the Precision class has compareTo() and equals() with both epsilon and ULP.

How to find current transaction level?

Run this:

SELECT CASE transaction_isolation_level 
WHEN 0 THEN 'Unspecified' 
WHEN 1 THEN 'ReadUncommitted' 
WHEN 2 THEN 'ReadCommitted' 
WHEN 3 THEN 'Repeatable' 
WHEN 4 THEN 'Serializable' 
WHEN 5 THEN 'Snapshot' END AS TRANSACTION_ISOLATION_LEVEL 
FROM sys.dm_exec_sessions 
where session_id = @@SPID

docs.microsoft.com reference for the constant values.

Is there a command like "watch" or "inotifywait" on the Mac?

Here's a one-liner using sschober's tool.

$ while true; do kqwait ./file-to-watch.js; script-to-execute.sh; done

How to parseInt in Angular.js

This are to way to bind add too numbers

_x000D_
_x000D_
<!DOCTYPE html>_x000D_
<html>_x000D_
<script src="https://ajax.googleapis.com/ajax/libs/angularjs/1.6.9/angular.min.js"></script>_x000D_
<script>_x000D_
_x000D_
var app = angular.module("myApp", []);_x000D_
_x000D_
app.controller("myCtrl", function($scope) {_x000D_
$scope.total = function() { _x000D_
  return parseInt($scope.num1) + parseInt($scope.num2) _x000D_
}_x000D_
})_x000D_
</script>_x000D_
<body ng-app='myApp' ng-controller='myCtrl'>_x000D_
_x000D_
<input type="number" ng-model="num1">_x000D_
<input type="number" ng-model="num2">_x000D_
Total:{{num1+num2}}_x000D_
_x000D_
Total: {{total() }}_x000D_
_x000D_
_x000D_
</body>_x000D_
</html>
_x000D_
_x000D_
_x000D_

Solving Quadratic Equation

How about accepting complex roots as solutions?

import math

# User inserting the values of a, b and c

a = float(input("Insert coefficient a: "))
b = float(input("Insert coefficient b: "))
c = float(input("Insert coefficient c: "))

discriminant = b**2 - 4 * a * c

if discriminant >= 0:
    x_1=(-b+math.sqrt(discriminant))/2*a
    x_2=(-b-math.sqrt(discriminant))/2*a
else:
    x_1= complex((-b/(2*a)),math.sqrt(-discriminant)/(2*a))
    x_2= complex((-b/(2*a)),-math.sqrt(-discriminant)/(2*a))

if discriminant > 0:
    print("The function has two distinct real roots: ", x_1, " and ", x_2)
elif discriminant == 0:
    print("The function has one double root: ", x_1)
else:
    print("The function has two complex (conjugate) roots: ", x_1, " and ", x_2)

ACCESS_FINE_LOCATION AndroidManifest Permissions Not Being Granted

just remove s from the permission you are using sss you have to use ss

Does Java SE 8 have Pairs or Tuples?

Eclipse Collections has Pair and all combinations of primitive/object Pairs (for all eight primitives).

The Tuples factory can create instances of Pair, and the PrimitiveTuples factory can be used to create all combinations of primitive/object pairs.

We added these before Java 8 was released. They were useful to implement key/value Iterators for our primitive maps, which we also support in all primitive/object combinations.

If you're willing to add the extra library overhead, you can use Stuart's accepted solution and collect the results into a primitive IntList to avoid boxing. We added new methods in Eclipse Collections 9.0 to allow for Int/Long/Double collections to be created from Int/Long/Double Streams.

IntList list = IntLists.mutable.withAll(intStream);

Note: I am a committer for Eclipse Collections.

Swift do-try-catch syntax

There are two important points to the Swift 2 error handling model: exhaustiveness and resiliency. Together, they boil down to your do/catch statement needing to catch every possible error, not just the ones you know you can throw.

Notice that you don't declare what types of errors a function can throw, only whether it throws at all. It's a zero-one-infinity sort of problem: as someone defining a function for others (including your future self) to use, you don't want to have to make every client of your function adapt to every change in the implementation of your function, including what errors it can throw. You want code that calls your function to be resilient to such change.

Because your function can't say what kind of errors it throws (or might throw in the future), the catch blocks that catch it errors don't know what types of errors it might throw. So, in addition to handling the error types you know about, you need to handle the ones you don't with a universal catch statement -- that way if your function changes the set of errors it throws in the future, callers will still catch its errors.

do {
    let sandwich = try makeMeSandwich(kitchen)
    print("i eat it \(sandwich)")
} catch SandwichError.NotMe {
    print("Not me error")
} catch SandwichError.DoItYourself {
    print("do it error")
} catch let error {
    print(error.localizedDescription)
}

But let's not stop there. Think about this resilience idea some more. The way you've designed your sandwich, you have to describe errors in every place where you use them. That means that whenever you change the set of error cases, you have to change every place that uses them... not very fun.

The idea behind defining your own error types is to let you centralize things like that. You could define a description method for your errors:

extension SandwichError: CustomStringConvertible {
    var description: String {
        switch self {
            case NotMe: return "Not me error"
            case DoItYourself: return "Try sudo"
        }
    }
}

And then your error handling code can ask your error type to describe itself -- now every place where you handle errors can use the same code, and handle possible future error cases, too.

do {
    let sandwich = try makeMeSandwich(kitchen)
    print("i eat it \(sandwich)")
} catch let error as SandwichError {
    print(error.description)
} catch {
    print("i dunno")
}

This also paves the way for error types (or extensions on them) to support other ways of reporting errors -- for example, you could have an extension on your error type that knows how to present a UIAlertController for reporting the error to an iOS user.

Node Express sending image files as API response

There is an api in Express.

res.sendFile

app.get('/report/:chart_id/:user_id', function (req, res) {
    // res.sendFile(filepath);
});

http://expressjs.com/en/api.html#res.sendFile

convert php date to mysql format

This site has two pretty simple solutions - just check the code, I provided the descriptions in case you wanted them - saves you some clicks.

http://www.richardlord.net/blog/dates-in-php-and-mysql

1.One common solution is to store the dates in DATETIME fields and use PHPs date() and strtotime() functions to convert between PHP timestamps and MySQL DATETIMEs. The methods would be used as follows -

$mysqldate = date( 'Y-m-d H:i:s', $phpdate );
$phpdate = strtotime( $mysqldate );

2.Our second option is to let MySQL do the work. MySQL has functions we can use to convert the data at the point where we access the database. UNIX_TIMESTAMP will convert from DATETIME to PHP timestamp and FROM_UNIXTIME will convert from PHP timestamp to DATETIME. The methods are used within the SQL query. So we insert and update dates using queries like this -

$query = "UPDATE table SET
    datetimefield = FROM_UNIXTIME($phpdate)
    WHERE...";
$query = "SELECT UNIX_TIMESTAMP(datetimefield)
    FROM table WHERE...";

How to convert datetime to timestamp using C#/.NET (ignoring current timezone)

I'm not exactly sure what it is that you want. Do you want a TimeStamp? Then you can do something simple like:

TimeStamp ts = TimeStamp.FromTicks(value.ToUniversalTime().Ticks);

Since you named a variable epoch, do you want the Unix time equivalent of your date?

DateTime unixStart = DateTime.SpecifyKind(new DateTime(1970, 1, 1), DateTimeKind.Utc);
long epoch = (long)Math.Floor((value.ToUniversalTime() - unixStart).TotalSeconds);

Cannot install packages using node package manager in Ubuntu

For me the fix was removing the node* packages and also the npm packages.

Then a fresh install as:

sudo apt-get install autoclean
sudo apt-get install nodejs-legacy
npm install

Prefer composition over inheritance?

Inheritance is pretty enticing especially coming from procedural-land and it often looks deceptively elegant. I mean all I need to do is add this one bit of functionality to some other class, right? Well, one of the problems is that

inheritance is probably the worst form of coupling you can have

Your base class breaks encapsulation by exposing implementation details to subclasses in the form of protected members. This makes your system rigid and fragile. The more tragic flaw however is the new subclass brings with it all the baggage and opinion of the inheritance chain.

The article, Inheritance is Evil: The Epic Fail of the DataAnnotationsModelBinder, walks through an example of this in C#. It shows the use of inheritance when composition should have been used and how it could be refactored.

What's the difference between window.location and document.location in JavaScript?

According to the W3C, they are the same. In reality, for cross browser safety, you should use window.location rather than document.location.

See: http://www.w3.org/TR/html/browsers.html#dom-location

How to initialize const member variable in a class?

This is the right way to do. You can try this code.

#include <iostream>

using namespace std;

class T1 {
    const int t;

    public:
        T1():t(100) {
            cout << "T1 constructor: " << t << endl;
        }
};

int main() {
    T1 obj;
    return 0;
}

if you are using C++10 Compiler or below then you can not initialize the cons member at the time of declaration. So here it is must to make constructor to initialise the const data member. It is also must to use initialiser list T1():t(100) to get memory at instant.

Regex Letters, Numbers, Dashes, and Underscores

Just escape the dashes to prevent them from being interpreted (I don't think underscore needs escaping, but it can't hurt). You don't say which regex you are using.

([A-Za-z0-9\-\_]+)

JavaScript: Create and destroy class instance through class method

1- There is no way to actually destroy an object in javascript, but using delete, we could remove a reference from an object:

var obj = {};
obj.mypointer = null;
delete obj.mypointer;

2- The important point about the delete keyword is that it does not actually destroy the object BUT if only after deleting that reference to the object, there is no other reference left in the memory pointed to the same object, that object would be marked as collectible. The delete keyword deletes the reference but doesn't GC the actual object. it means if you have several references of the same object, the object will be collected just after you delete all the pointed references.

3- there are also some tricks and workarounds that could help us out, when we want to make sure we do not leave any memory leaks behind. for instance if you have an array consisting several objects, without any other pointed reference to those objects, if you recreate the array all those objects would be killed. For instance if you have var array = [{}, {}] overriding the value of the array like array = [] would remove the references to the two objects inside the array and those two objects would be marked as collectible.

4- for your solution the easiest way is just this:

var storage = {};
storage.instance = new Class();
//since 'storage.instance' is your only reference to the object, whenever you wanted to destroy do this:
storage.instance = null;
// OR
delete storage.instance;

As mentioned above, either setting storage.instance = null or delete storage.instance would suffice to remove the reference to the object and allow it to be cleaned up by the GC. The difference is that if you set it to null then the storage object still has a property called instance (with the value null). If you delete storage.instance then the storage object no longer has a property named instance.

and WHAT ABOUT destroy method ??

the paradoxical point here is if you use instance.destroy in the destroy function you have no access to the actual instance pointer, and it won't let you delete it.

The only way is to pass the reference to the destroy function and then delete it:

// Class constructor
var Class = function () {
     this.destroy = function (baseObject, refName) {
         delete baseObject[refName];
     };
};

// instanciate
var storage = {};
storage.instance = new Class();
storage.instance.destroy(object, "instance");
console.log(storage.instance); // now it is undefined

BUT if I were you I would simply stick to the first solution and delete the object like this:

storage.instance = null;
// OR
delete storage.instance;

WOW it was too much :)

MongoDB: Server has startup warnings ''Access control is not enabled for the database''

You need to delete your old db folder and recreate new one. It will resolve your issue.

react native get TextInput value

Simply do it.

this.state={f_name:""};

textChangeHandler = async (key, val) => {
    await this.setState({ [key]: val });
}

<Textfield onChangeText={val => this.textChangeHandler('f_name', val)}>

Iterate through Nested JavaScript Objects

modify from Peter Olson's answer: https://stackoverflow.com/a/8085118

  1. can avoid string value !obj || (typeof obj === 'string'
  2. can custom your key

var findObjectByKeyVal= function (obj, key, val) {
  if (!obj || (typeof obj === 'string')) {
    return null
  }
  if (obj[key] === val) {
    return obj
  }

  for (var i in obj) {
    if (obj.hasOwnProperty(i)) {
      var found = findObjectByKeyVal(obj[i], key, val)
      if (found) {
        return found
      }
    }
  }
  return null
}

HTTP GET in VBS

You haven't at time of writing described what you are going to do with the response or what its content type is. An answer already contains a very basic usage of MSXML2.XMLHTTP (I recommend the more explicit MSXML2.XMLHTTP.3.0 progID) however you may need to do different things with the response, it may not be text.

The XMLHTTP also has a responseBody property which is a byte array version of the reponse and there is a responseStream which is an IStream wrapper for the response.

Note that in a server-side requirement (e.g., VBScript hosted in ASP) you would use MSXML.ServerXMLHTTP.3.0 or WinHttp.WinHttpRequest.5.1 (which has a near identical interface).

Here is an example of using XmlHttp to fetch a PDF file and store it:-

Dim oXMLHTTP
Dim oStream

Set oXMLHTTP = CreateObject("MSXML2.XMLHTTP.3.0")

oXMLHTTP.Open "GET", "http://someserver/folder/file.pdf", False
oXMLHTTP.Send

If oXMLHTTP.Status = 200 Then
    Set oStream = CreateObject("ADODB.Stream")
    oStream.Open
    oStream.Type = 1
    oStream.Write oXMLHTTP.responseBody
    oStream.SaveToFile "c:\somefolder\file.pdf"
    oStream.Close
End If

Android: failed to convert @drawable/picture into a drawable

In Android Studio your resource(images) file name cannot start with NUMERIC and It cannot contain any BIG character. To solve your problem, do as Aliyah said. Just restart your IDE. This solved my problem too.

Python error: AttributeError: 'module' object has no attribute

More accurately, your mod1 and lib directories are not modules, they are packages. The file mod11.py is a module.

Python does not automatically import subpackages or modules. You have to explicitly do it, or "cheat" by adding import statements in the initializers.

>>> import lib
>>> dir(lib)
['__builtins__', '__doc__', '__file__', '__name__', '__package__', '__path__']
>>> import lib.pkg1
>>> import lib.pkg1.mod11
>>> lib.pkg1.mod11.mod12()
mod12

An alternative is to use the from syntax to "pull" a module from a package into you scripts namespace.

>>> from lib.pkg1 import mod11

Then reference the function as simply mod11.mod12().

How to convert List<Integer> to int[] in Java?

No one mentioned yet streams added in Java 8 so here it goes:

int[] array = list.stream().mapToInt(i->i).toArray();
//OR
//int[] array = list.stream().mapToInt(Integer::intValue).toArray();

Thought process:

  • simple Stream#toArray returns Object[], so it is not what we want. Also Stream#toArray(IntFunction<A[]> generator) doesn't do what we want because generic type A can't represent primitive int

  • so it would be nice to have some stream which could handle primitive type int instead of wrapper Integer, because its toArray method will most likely also return int[] array (returning something else like Object[] or even boxed Integer[] would be unnatural here). And fortunately Java 8 has such stream which is IntStream

  • so now only thing we need to figure out is how to convert our Stream<Integer> (which will be returned from list.stream()) to that shiny IntStream. Here Stream#mapToInt(ToIntFunction<? super T> mapper) method comes to a rescue. All we need to do is pass to it mapping from Integer to int. We could use something like Integer#intValue which returns int like :

      mapToInt( (Integer i) -> i.intValue() )  
    

(or if someone prefers mapToInt(Integer::intValue) )

but similar code can be generated using unboxing, since compiler knows that result of this lambda must be int (lambda in mapToInt is implementation of ToIntFunction interface which expects body for int applyAsInt(T value) method which is expected to return int).

So we can simply write

    mapToInt((Integer i)->i)

Also since Integer type in (Integer i) can be inferred by compiler because List<Integer>#stream() returns Stream<Integer> we can also skip it which leaves us with

    mapToInt(i -> i)

Unable to load DLL 'SQLite.Interop.dll'

I got the same problem. However, finally, I can fix it. Currently, I use Visual Studio 2013 Community Edition. I just use Add->Existing Item... and browse to where the SQLite.Data.SQLite files are in (my case is 'C:\Program Files (x86)\System.Data.SQLite\2013\bin'). Please don't forget to change type of what you will include to Assembly Files (*.dll; *.pdb). Choose 'SQLite.Interop.dll' in that folder. From there and then, I can continue without any problems at all. Good luck to you all. ^_^ P.S. I create web form application. I haven't tried in window form application or others yet.

Codeigniter $this->db->get(), how do I return values for a specific row?

Incase you are dynamically getting your data e.g When you need data based on the user logged in by their id use consider the following code example for a No Active Record:

 $this->db->query('SELECT * FROM my_users_table WHERE id = ?', $this->session->userdata('id'));

 return $query->row_array();

This will return a specific row based on your the set session data of user.

Add space between two particular <td>s

Try this Demo

HTML

<table>
    <tr>
        <td>One</td>
        <td>Two</td>
        <td>Three</td>
        <td>Four</td>
    </tr>
</table>

CSS

td:nth-of-type(2) {
   padding-right: 10px;
}

Virtualenv Command Not Found

this works in ubuntu 18 and above (not tested in previous versions):

sudo apt install python3-virtualenv

Auto start print html page using javascript

For me, adding <script>window.print();</script> to the end of the page worked.


I didn't need the type="text/javascript" attribute, or even for the page to be wrapped in a <body> tag. However, all of my previous attempts to intuitively use the answers suggested here, of just writing window.onload=window.print or longer versions such as window.onload=()=>window.print(); did not work, and of course calling print on the newly created window does not wait for the contents to load.

jQuery - Redirect with post data

why not just use a button instead of submit. clicking the button will let you construct a proper url for your browser to redirect to.

$("#button").click(function() {
   var url = 'site.com/process.php?';
   $('form input').each(function() {
       url += 'key=' + $(this).val() + "&";
   });
   // handle removal of last &.

   window.location.replace(url);
});

preventDefault() on an <a> tag

Try something like:

$('div.toggle').hide();
$('ul.product-info li a').click(function(event) {
    event.preventDefault();
    $(this).next('div').slideToggle(200);
});

Here is the page about that in the jQuery documentation

How to determine if a list of polygon points are in clockwise order?

While these answers are correct, they are more mathematically intense than necessary. Assume map coordinates, where the most north point is the highest point on the map. Find the most north point, and if 2 points tie, it is the most north then the most east (this is the point that lhf uses in his answer). In your points,

point[0] = (5,0)

point[1] = (6,4)

point[2] = (4,5)

point[3] = (1,5)

point[4] = (1,0)

If we assume that P2 is the most north then east point either the previous or next point determine clockwise, CW, or CCW. Since the most north point is on the north face, if the P1 (previous) to P2 moves east the direction is CW. In this case, it moves west, so the direction is CCW as the accepted answer says. If the previous point has no horizontal movement, then the same system applies to the next point, P3. If P3 is west of P2, it is, then the movement is CCW. If the P2 to P3 movement is east, it's west in this case, the movement is CW. Assume that nte, P2 in your data, is the most north then east point and the prv is the previous point, P1 in your data, and nxt is the next point, P3 in your data, and [0] is horizontal or east/west where west is less than east, and [1] is vertical.

if (nte[0] >= prv[0] && nxt[0] >= nte[0]) return(CW);
if (nte[0] <= prv[0] && nxt[0] <= nte[0]) return(CCW);
// Okay, it's not easy-peasy, so now, do the math
if (nte[0] * nxt[1] - nte[1] * nxt[0] - prv[0] * (nxt[1] - crt[1]) + prv[1] * (nxt[0] - nte[0]) >= 0) return(CCW); // For quadrant 3 return(CW)
return(CW) // For quadrant 3 return (CCW)

Eclipse 3.5 Unable to install plugins

I had a similar problem setting up eclipse in the office. I had set up the for HTTP, HTTPS and SOCKS in:

Window>pref>general>network connections

Clearing the proxy settings for SOCKS fixed the problem for me.

"Connection for controluser as defined in your configuration failed" with phpMyAdmin in XAMPP

on ubuntu 18.04 in etc/phpmyadmin/config.inc.php comment all the block

Optional: User for advanced features

How to run Conda?

Open your terminal and type the following command to add anaconda to environment path

for anaconda 2 :

export PATH=~/anaconda2/bin:$PATH

for anaconda 3 :

export PATH=~/anaconda3/bin:$PATH

Then to check the conda version just type,

conda --version

Create an environment using the following command,

conda create --name myenv

Activate the source using,

source activate myenv

Then your anaconda IDE is ready!!!

Map<String, String>, how to print both the "key string" and "value string" together

final Map<String, String> mss1 = new ProcessBuilder().environment();
mss1.entrySet()
        .stream()
        //depending on how you want to join K and V use different delimiter
        .map(entry -> 
        String.join(":", entry.getKey(),entry.getValue()))
        .forEach(System.out::println);

Click button copy to clipboard using jQuery

you can copy an individual text apart from an HTML element's text.

        var copyToClipboard = function (text) {
            var $txt = $('<textarea />');

            $txt.val(text)
                .css({ width: "1px", height: "1px" })
                .appendTo('body');

            $txt.select();

            if (document.execCommand('copy')) {
                $txt.remove();
            }
        };

Force browser to clear cache

I had a case where I would take photos of clients online and would need to update the div if a photo is changed. Browser was still showing the old photo. So I used the hack of calling a random GET variable, which would be unique every time. Here it is if it could help anybody

<img src="/photos/userid_73.jpg?random=<?php echo rand() ?>" ...

EDIT As pointed out by others, following is much more efficient solution since it will reload images only when they are changed, identifying this change by the file size:

<img src="/photos/userid_73.jpg?modified=<? filemtime("/photos/userid_73.jpg")?>"

How to group time by hour or by 10 minutes

select from_unixtime( 600 * ( unix_timestamp( [Date] ) % 600 ) ) AS RecT, avg(Value)
from [FRIIB].[dbo].[ArchiveAnalog]
group by RecT
order by RecT;

replace the two 600 by any number of seconds you want to group.

If you need this often and the table doesn't change, as the name Archive suggests, it would probably be a bit faster to convert and store the date (& time) as a unixtime in the table.

Add / remove input field dynamically with jQuery

Another solution could be:

<script>
$(document)
        .ready(
                function() {
                    var wrapper = $(".myFields");
                    $(add_button)
                            .click(
                                    function(e) {
                                        e.preventDefault();
                                        $(wrapper)
                                                .append(
                                                        '.....'); //add fields here
                                    });
                    $(wrapper).on("click", ".delFld", function(e) {
                        e.preventDefault();
                        $(this).parent('div').remove();
                    })
                }); 
</script>

Source: Here

How can I remove Nan from list Python/NumPy

I like to remove missing values from a list like this:

list_no_nan = [x for x in list_with_nan if pd.notnull(x)]

How to use the 'main' parameter in package.json?

Just think of it as the "starting point".

In a sense of object-oriented programming, say C#, it's the init() or constructor of the object class, that's what "entry point" meant.

For example

public class IamMain  // when export and require this guy
{
    public IamMain()  // this is "main"
    {...}

    ...   // many others such as function, properties, etc.
}

How to force file download with PHP

Display your file first and set its value into url.

index.php

<a href="download.php?download='.$row['file'].'" title="Download File">

download.php

<?php
/*db connectors*/
include('dbconfig.php');

/*function to set your files*/
function output_file($file, $name, $mime_type='')
{
    if(!is_readable($file)) die('File not found or inaccessible!');
    $size = filesize($file);
    $name = rawurldecode($name);
    $known_mime_types=array(
        "htm" => "text/html",
        "exe" => "application/octet-stream",
        "zip" => "application/zip",
        "doc" => "application/msword",
        "jpg" => "image/jpg",
        "php" => "text/plain",
        "xls" => "application/vnd.ms-excel",
        "ppt" => "application/vnd.ms-powerpoint",
        "gif" => "image/gif",
        "pdf" => "application/pdf",
        "txt" => "text/plain",
        "html"=> "text/html",
        "png" => "image/png",
        "jpeg"=> "image/jpg"
    );

    if($mime_type==''){
        $file_extension = strtolower(substr(strrchr($file,"."),1));
        if(array_key_exists($file_extension, $known_mime_types)){
            $mime_type=$known_mime_types[$file_extension];
        } else {
            $mime_type="application/force-download";
        };
    };
    @ob_end_clean();
    if(ini_get('zlib.output_compression'))
    ini_set('zlib.output_compression', 'Off');
    header('Content-Type: ' . $mime_type);
    header('Content-Disposition: attachment; filename="'.$name.'"');
    header("Content-Transfer-Encoding: binary");
    header('Accept-Ranges: bytes');

    if(isset($_SERVER['HTTP_RANGE']))
    {
        list($a, $range) = explode("=",$_SERVER['HTTP_RANGE'],2);
        list($range) = explode(",",$range,2);
        list($range, $range_end) = explode("-", $range);
        $range=intval($range);
        if(!$range_end) {
            $range_end=$size-1;
        } else {
            $range_end=intval($range_end);
        }

        $new_length = $range_end-$range+1;
        header("HTTP/1.1 206 Partial Content");
        header("Content-Length: $new_length");
        header("Content-Range: bytes $range-$range_end/$size");
    } else {
        $new_length=$size;
        header("Content-Length: ".$size);
    }

    $chunksize = 1*(1024*1024);
    $bytes_send = 0;
    if ($file = fopen($file, 'r'))
    {
        if(isset($_SERVER['HTTP_RANGE']))
        fseek($file, $range);

        while(!feof($file) &&
            (!connection_aborted()) &&
            ($bytes_send<$new_length)
        )
        {
            $buffer = fread($file, $chunksize);
            echo($buffer);
            flush();
            $bytes_send += strlen($buffer);
        }
        fclose($file);
    } else
        die('Error - can not open file.');
    die();
}
set_time_limit(0);

/*set your folder*/
$file_path='uploads/'."your file";

/*output must be folder/yourfile*/

output_file($file_path, ''."your file".'', $row['type']);

/*back to index.php while downloading*/
header('Location:index.php');
?>

error: This is probably not a problem with npm. There is likely additional logging output above

Please delete package-lock.json and clear npm cache with npm cache clear --force and delete whole node_modules directory

Finally install or update packages again with npm install / npm update You can also add any new packages with npm install <package-name>

This fixed for me.

Thanks and happy coding.

How to filter by IP address in Wireshark?

Other answers already cover how to filter by an address, but if you would like to exclude an address use

ip.addr < 192.168.0.11

How can I count the number of matches for a regex?

From Java 9, you can use the stream provided by Matcher.results()

long matches = matcher.results().count();

The type arguments for method cannot be inferred from the usage

As I mentioned in my comment, I think the reason why this doesn't work is because the compiler can't infer types based on generic constraints.

Below is an alternative implementation that will compile. I've revised the IAccess interface to only have the T generic type parameter.

interface ISignatur<T>
{
    Type Type { get; }
}

interface IAccess<T>
{
    ISignatur<T> Signature { get; }
    T Value { get; set; }
}

class Signatur : ISignatur<bool>
{
    public Type Type
    {
        get { return typeof(bool); }
    }
}

class ServiceGate
{
    public IAccess<T> Get<T>(ISignatur<T> sig)
    {
        throw new NotImplementedException();
    }
}

static class Test
{
    static void Main()
    {
        ServiceGate service = new ServiceGate();
        var access = service.Get(new Signatur());
    }
}

How do I get bit-by-bit data from an integer value in C?

Here's one way to do it—there are many others:

bool b[4];
int v = 7;  // number to dissect

for (int j = 0;  j < 4;  ++j)
   b [j] =  0 != (v & (1 << j));

It is hard to understand why use of a loop is not desired, but it is easy enough to unroll the loop:

bool b[4];
int v = 7;  // number to dissect

b [0] =  0 != (v & (1 << 0));
b [1] =  0 != (v & (1 << 1));
b [2] =  0 != (v & (1 << 2));
b [3] =  0 != (v & (1 << 3));

Or evaluating constant expressions in the last four statements:

b [0] =  0 != (v & 1);
b [1] =  0 != (v & 2);
b [2] =  0 != (v & 4);
b [3] =  0 != (v & 8);

Serialize object to query string in JavaScript/jQuery

You want $.param(): http://api.jquery.com/jQuery.param/

Specifically, you want this:

var data = { one: 'first', two: 'second' };
var result = $.param(data);

When given something like this:

{a: 1, b : 23, c : "te!@#st"}

$.param will return this:

a=1&b=23&c=te!%40%23st

requestFeature() must be called before adding content

Well, just do what the error message tells you.

Don't call setContentView() before requestFeature().

Note:

As said in comments, for both ActionBarSherlock and AppCompat library, it's necessary to call requestFeature() before super.onCreate()

scrollIntoView Scrolls just too far

Based on the answer of Arseniy-II: I had the Use-Case where the scrolling entity was not window itself but a inner Template (in this case a div). In this scenario we need to set an ID for the scrolling container and get it via getElementById to use its scrolling function:

<div class="scroll-container" id="app-content">
  ...
</div>
const yOffsetForScroll = -100
const y = document.getElementById(this.idToScroll).getBoundingClientRect().top;
const main = document.getElementById('app-content');
main.scrollTo({
    top: y + main.scrollTop + yOffsetForScroll,
    behavior: 'smooth'
  });

Leaving it here in case someone faces a similar situation!

Fatal error: Please read "Security" section of the manual to find out how to run mysqld as root

osx could be using launchctl to launch mysql. Try this:

sudo launchctl unload -w /Library/LaunchDaemons/com.mysql.mysqld.plist

PHP fwrite new line

You append a newline to both the username and the password, i.e. the output would be something like

Sebastian
password
John
hfsjaijn

use fwrite($fh,$user." ".$password."\n"); instead to have them both on one line.
Or use fputcsv() to write the data and fgetcsv() to fetch it. This way you would at least avoid encoding problems like e.g. with $username='Charles, III';

...i.e. setting aside all the things that are wrong about storing plain passwords in plain files and using _GET for this type of operation (use _POST instead) ;-)

Java Switch Statement - Is "or"/"and" possible?

Observations on an interesting Switch case trap --> fall through of switch

"The break statements are necessary because without them, statements in switch blocks fall through:" Java Doc's example

Snippet of consecutive case without break:

    char c = 'A';/* switch with lower case */;
    switch(c) {
        case 'a':
            System.out.println("a");
        case 'A':
            System.out.println("A");
            break;
    }

O/P for this case is:

A

But if you change value of c, i.e., char c = 'a';, then this get interesting.

O/P for this case is:

a A

Even though the 2nd case test fails, program goes onto print A, due to missing break which causes switch to treat the rest of the code as a block. All statements after the matching case label are executed in sequence.

How to delete last item in list?

If you have a list of lists (tracked_output_sheet in my case), where you want to delete last element from each list, you can use the following code:

interim = []
for x in tracked_output_sheet:interim.append(x[:-1])
tracked_output_sheet= interim

Is it possible to append to innerHTML without destroying descendants' event listeners?

Yes it is possible if you bind events using tag attribute onclick="sayHi()" directly in template similar like your <body onload="start()"> - this approach similar to frameworks angular/vue/react/etc. You can also use <template> to operate on 'dynamic' html like here. It is not strict unobtrusive js however it is acceptable for small projects

_x000D_
_x000D_
function start() {_x000D_
  mydiv.innerHTML += "bar";_x000D_
}_x000D_
_x000D_
function sayHi() {_x000D_
  alert("hi");_x000D_
}
_x000D_
<body onload="start()">_x000D_
  <div id="mydiv" style="border: solid red 2px">_x000D_
    <span id="myspan" onclick="sayHi()">foo</span>_x000D_
  </div>_x000D_
</body>
_x000D_
_x000D_
_x000D_

Using group by on multiple columns

Here I am going to explain not only the GROUP clause use, but also the Aggregate functions use.

The GROUP BY clause is used in conjunction with the aggregate functions to group the result-set by one or more columns. e.g.:

-- GROUP BY with one parameter:
SELECT column_name, AGGREGATE_FUNCTION(column_name)
FROM table_name
WHERE column_name operator value
GROUP BY column_name;

-- GROUP BY with two parameters:
SELECT
    column_name1,
    column_name2,
    AGGREGATE_FUNCTION(column_name3)
FROM
    table_name
GROUP BY
    column_name1,
    column_name2;

Remember this order:

  1. SELECT (is used to select data from a database)

  2. FROM (clause is used to list the tables)

  3. WHERE (clause is used to filter records)

  4. GROUP BY (clause can be used in a SELECT statement to collect data across multiple records and group the results by one or more columns)

  5. HAVING (clause is used in combination with the GROUP BY clause to restrict the groups of returned rows to only those whose the condition is TRUE)

  6. ORDER BY (keyword is used to sort the result-set)

You can use all of these if you are using aggregate functions, and this is the order that they must be set, otherwise you can get an error.

Aggregate Functions are:

MIN() returns the smallest value in a given column

MAX() returns the maximum value in a given column.

SUM() returns the sum of the numeric values in a given column

AVG() returns the average value of a given column

COUNT() returns the total number of values in a given column

COUNT(*) returns the number of rows in a table

SQL script examples about using aggregate functions:

Let's say we need to find the sale orders whose total sale is greater than $950. We combine the HAVING clause and the GROUP BY clause to accomplish this:

SELECT 
    orderId, SUM(unitPrice * qty) Total
FROM
    OrderDetails
GROUP BY orderId
HAVING Total > 950;

Counting all orders and grouping them customerID and sorting the result ascendant. We combine the COUNT function and the GROUP BY, ORDER BY clauses and ASC:

SELECT 
    customerId, COUNT(*)
FROM
    Orders
GROUP BY customerId
ORDER BY COUNT(*) ASC;

Retrieve the category that has an average Unit Price greater than $10, using AVG function combine with GROUP BY and HAVING clauses:

SELECT 
    categoryName, AVG(unitPrice)
FROM
    Products p
INNER JOIN
    Categories c ON c.categoryId = p.categoryId
GROUP BY categoryName
HAVING AVG(unitPrice) > 10;

Getting the less expensive product by each category, using the MIN function in a subquery:

SELECT categoryId,
       productId,
       productName,
       unitPrice
FROM Products p1
WHERE unitPrice = (
                SELECT MIN(unitPrice)
                FROM Products p2
                WHERE p2.categoryId = p1.categoryId)

The following statement groups rows with the same values in both categoryId and productId columns:

SELECT 
    categoryId, categoryName, productId, SUM(unitPrice)
FROM
    Products p
INNER JOIN
    Categories c ON c.categoryId = p.categoryId
GROUP BY categoryId, productId

MS SQL Date Only Without Time

WHERE DATEDIFF(day, tstamp, @dateParam) = 0

This should get you there if you don't care about time.

This is to answer the meta question of comparing the dates of two values when you don't care about the time.

Duplicate ID, tag null, or parent id with another fragment for com.google.android.gms.maps.MapFragment

I had the same issue and was able to resolve it by manually removing the MapFragment in the onDestroy() method of the Fragment class. Here is code that works and references the MapFragment by ID in the XML:

@Override
public void onDestroyView() {
    super.onDestroyView();
    MapFragment f = (MapFragment) getFragmentManager()
                                         .findFragmentById(R.id.map);
    if (f != null) 
        getFragmentManager().beginTransaction().remove(f).commit();
}

If you don't remove the MapFragment manually, it will hang around so that it doesn't cost a lot of resources to recreate/show the map view again. It seems that keeping the underlying MapView is great for switching back and forth between tabs, but when used in fragments this behavior causes a duplicate MapView to be created upon each new MapFragment with the same ID. The solution is to manually remove the MapFragment and thus recreate the underlying map each time the fragment is inflated.

I also noted this in another answer [1].

Should a retrieval method return 'null' or throw an exception when it can't produce the return value?

As long as it's supposed to return a reference to the object, returning a NULL should be good.

However, if it's returning the whole bloody thing (like in C++ if you do: 'return blah;' rather than 'return &blah;' (or 'blah' is a pointer), then you can't return a NULL, because it's not of type 'object'. In that case, throwing an exception, or returning a blank object that doesn't have a success flag set is how I would approach the problem.

JavaScript - XMLHttpRequest, Access-Control-Allow-Origin errors

I think you've missed the point of access control.

A quick recap on why CORS exists: Since JS code from a website can execute XHR, that site could potentially send requests to other sites, masquerading as you and exploiting the trust those sites have in you(e.g. if you have logged in, a malicious site could attempt to extract information or execute actions you never wanted) - this is called a CSRF attack. To prevent that, web browsers have very stringent limitations on what XHR you can send - you are generally limited to just your domain, and so on.

Now, sometimes it's useful for a site to allow other sites to contact it - sites that provide APIs or services, like the one you're trying to access, would be prime candidates. CORS was developed to allow site A(e.g. paste.ee) to say "I trust site B, so you can send XHR from it to me". This is specified by site A sending "Access-Control-Allow-Origin" headers in its responses.

In your specific case, it seems that paste.ee doesn't bother to use CORS. Your best bet is to contact the site owner and find out why, if you want to use paste.ee with a browser script. Alternatively, you could try using an extension(those should have higher XHR privileges).

Error With Port 8080 already in use

on Mac, how I usually solve it

  1. open terminal and cd to downloaded-apache-files-folder/bin (i.e to the folder where shutdown.sh file is located)
  2. enter "sh shutdown.sh" as a terminal command
  3. restart Tomcat/Eclipse..tada!

Hope this helps OP or someone else reading

Difference between Hashing a Password and Encrypting it

I've always thought that Encryption can be converted both ways, in a way that the end value can bring you to original value and with Hashing you'll not be able to revert from the end result to the original value.

When should I use git pull --rebase?

I think you should use git pull --rebase when collaborating with others on the same branch. You are in your work ? commit ? work ? commit cycle, and when you decide to push your work your push is rejected, because there's been parallel work on the same branch. At this point I always do a pull --rebase. I do not use squash (to flatten commits), but I rebase to avoid the extra merge commits.

As your Git knowledge increases you find yourself looking a lot more at history than with any other version control systems I've used. If you have a ton of small merge commits, it's easy to lose focus of the bigger picture that's happening in your history.

This is actually the only time I do rebasing(*), and the rest of my workflow is merge based. But as long as your most frequent committers do this, history looks a whole lot better in the end.

(*) While teaching a Git course, I had a student arrest me on this, since I also advocated rebasing feature branches in certain circumstances. And he had read this answer ;) Such rebasing is also possible, but it always has to be according to a pre-arranged/agreed system, and as such should not "always" be applied. And at that time I usually don't do pull --rebase either, which is what the question is about ;)

How can I programmatically freeze the top row of an Excel worksheet in Excel 2007 VBA?

Rows("2:2").Select
ActiveWindow.FreezePanes = True

Select a different range for a different effect, much the same way you would do manually. The "Freeze Top Row" really just is a shortcut new in Excel 2007 (and up), it contains no added functionality compared to earlier versions of Excel.

Render HTML to an image

The only library that I got to work for Chrome, Firefox and MS Edge was rasterizeHTML. It outputs better quality that HTML2Canvas and is still supported unlike HTML2Canvas.

Getting Element and Downloading as PNG

var node= document.getElementById("elementId");
var canvas = document.createElement("canvas");
canvas.height = node.offsetHeight;
canvas.width = node.offsetWidth;
var name = "test.png"

rasterizeHTML.drawHTML(node.outerHTML, canvas)
     .then(function (renderResult) {
            if (navigator.msSaveBlob) {
                window.navigator.msSaveBlob(canvas.msToBlob(), name);
            } else {
                const a = document.createElement("a");
                document.body.appendChild(a);
                a.style = "display: none";
                a.href = canvas.toDataURL();
                a.download = name;
                a.click();
                document.body.removeChild(a);
            }
     });

Difference between InvariantCulture and Ordinal string comparison

InvariantCulture

Uses a "standard" set of character orderings (a,b,c, ... etc.). This is in contrast to some specific locales, which may sort characters in different orders ('a-with-acute' may be before or after 'a', depending on the locale, and so on).

Ordinal

On the other hand, looks purely at the values of the raw byte(s) that represent the character.


There's a great sample at http://msdn.microsoft.com/en-us/library/e6883c06.aspx that shows the results of the various StringComparison values. All the way at the end, it shows (excerpted):

StringComparison.InvariantCulture:
LATIN SMALL LETTER I (U+0069) is less than LATIN SMALL LETTER DOTLESS I (U+0131)
LATIN SMALL LETTER I (U+0069) is less than LATIN CAPITAL LETTER I (U+0049)
LATIN SMALL LETTER DOTLESS I (U+0131) is greater than LATIN CAPITAL LETTER I (U+0049)

StringComparison.Ordinal:
LATIN SMALL LETTER I (U+0069) is less than LATIN SMALL LETTER DOTLESS I (U+0131)
LATIN SMALL LETTER I (U+0069) is greater than LATIN CAPITAL LETTER I (U+0049)
LATIN SMALL LETTER DOTLESS I (U+0131) is greater than LATIN CAPITAL LETTER I (U+0049)

You can see that where InvariantCulture yields (U+0069, U+0049, U+00131), Ordinal yields (U+0049, U+0069, U+00131).

What is a practical, real world example of the Linked List?

A telephone chain is implemented directly as a linked list. Here's how it works:

  1. A group organizer collects the phone numbers of all members.

  2. The organizer assigns each member the number of one other member to call. (Sometimes they will assign their own number so that they know the message got through, but this is optional.)

  3. When a message needs to be sent, the organizer calls the head of the list and delivers the message.

  4. The head calls the number they were assigned and delivers the message.

  5. Step 4 is repeated until everyone has heard the message.

Obviously care must be taken to set up the list in step 2 so that everyone is linked. Also, the list is usually public so that if someone gets an answering machine or busy tone, they can call the next number down and keep the chain moving.

When should the xlsm or xlsb formats be used?

One could think that xlsb has only advantages over xlsm. The fact that xlsm is XML-based and xlsb is binary is that when workbook corruption occurs, you have better chances to repair a xlsm than a xlsb.

What is a 'workspace' in Visual Studio Code?

They call it a multi-root workspace, and with that you can do debugging easily because:

"With multi-root workspaces, Visual Studio Code searches across all folders for launch.json debug configuration files and displays them with the folder name as a suffix."

Say you have a server and a client folder inside your application folder. If you want to debug them together, without a workspace you have to start two Visual Studio Code instances, one for server, one for client and you need to switch back and forth.

But right now (1.24) you can't add a single file to a workspace, only folders, which is a little bit inconvenient.

Configuring Hibernate logging using Log4j XML config file?

Loki's answer points to the Hibernate 3 docs and provides good information, but I was still not getting the results I expected.

Much thrashing, waving of arms and general dead mouse runs finally landed me my cheese.

Because Hibernate 3 is using Simple Logging Facade for Java (SLF4J) (per the docs), if you are relying on Log4j 1.2 you will also need the slf4j-log4j12-1.5.10.jar if you are wanting to fully configure Hibernate logging with a log4j configuration file. Hope this helps the next guy.

How to detect query which holds the lock in Postgres?

Postgres has a very rich system catalog exposed via SQL tables. PG's statistics collector is a subsystem that supports collection and reporting of information about server activity.

Now to figure out the blocking PIDs you can simply query pg_stat_activity.

select pg_blocking_pids(pid) as blocked_by
from pg_stat_activity
where cardinality(pg_blocking_pids(pid)) > 0;

To, get the query corresponding to the blocking PID, you can self-join or use it as a where clause in a subquery.

SELECT query
FROM pg_stat_activity
WHERE pid IN (select unnest(pg_blocking_pids(pid)) as blocked_by from pg_stat_activity where cardinality(pg_blocking_pids(pid)) > 0);

Note: Since pg_blocking_pids(pid) returns an Integer[], so you need to unnest it before you use it in a WHERE pid IN clause.

Hunting for slow queries can be tedious sometimes, so have patience. Happy hunting.

Python Set Comprehension

primes = {x for x in range(2, 101) if all(x%y for y in range(2, min(x, 11)))}

I simplified the test a bit - if all(x%y instead of if not any(not x%y

I also limited y's range; there is no point in testing for divisors > sqrt(x). So max(x) == 100 implies max(y) == 10. For x <= 10, y must also be < x.

pairs = {(x, x+2) for x in primes if x+2 in primes}

Instead of generating pairs of primes and testing them, get one and see if the corresponding higher prime exists.

How do I bind Twitter Bootstrap tooltips to dynamically created elements?

If you have multiple tooltip configurations that you want to initialise, this works well for me.

$("body").tooltip({
    selector: '[data-toggle="tooltip"]'
});

You can then set the property on individual elements using data attributes.

Append data frames together in a for loop

Here are some tidyverse and custom function options that might work depending on your needs:

library(tidyverse)

# custom function to generate, filter, and mutate the data:
combine_dfs <- function(i){
 data_frame(x = rnorm(5), y = runif(5)) %>% 
    filter(x < y) %>% 
    mutate(x_plus_y = x + y) %>% 
    mutate(i = i)
}

df <- 1:5 %>% map_df(~combine_dfs(.))
df <- map_df(1:5, ~combine_dfs(.)) # both give the same results
> df %>% head()
# A tibble: 6 x 4
       x      y x_plus_y     i
   <dbl>  <dbl>    <dbl> <int>
1 -0.973 0.673    -0.300     1
2 -0.553 0.0463   -0.507     1
3  0.250 0.716     0.967     2
4 -0.745 0.0640   -0.681     2
5 -0.736 0.228    -0.508     2
6 -0.365 0.496     0.131     3

You could do something similar if you had a directory of files that needed to be combined:

dir_path <- '/path/to/data/test_directory/'
list.files(dir_path)

combine_files <- function(path, file){
  read_csv(paste0(path, file)) %>% 
    filter(a < b) %>% 
    mutate(a_plus_b = a + b) %>% 
    mutate(file_name = file) 
}

df <- list.files(dir_path, '\\.csv$') %>% 
  map_df(~combine_files(dir_path, .))

# or if you have Excel files, using the readxl package:
combine_xl_files <- function(path, file){
  readxl::read_xlsx(paste0(path, file)) %>% 
    filter(a < b) %>% 
    mutate(a_plus_b = a + b) %>% 
    mutate(file_name = file) 
}

df <- list.files(dir_path, '\\.xlsx$') %>% 
  map_df(~combine_xl_files(dir_path, .))

Select records from today, this week, this month php mysql

Everybody seems to refer to date being a column in the table.
I dont think this is good practice. The word date might just be a keyword in some coding language (maybe Oracle) so please change the columnname date to maybe JDate.
So will the following work better:

SELECT * FROM jokes WHERE JDate >= CURRENT_DATE() ORDER BY JScore DESC;

So we have a table called Jokes with columns JScore and JDate.