Programs & Examples On #Autotools

Autotools is a suite of programming tools (mainly autoconf, automake, and libtool) designed to assist in making source-code packages portable to many Unix-like systems.

possibly undefined macro: AC_MSG_ERROR

I have experienced this same problem under CentOS 7

In may case, the problem went off after installation of libcurl-devel (libcurl was already installed on this machine)

Make install, but not to default directories?

It could be dependent upon what is supported by the module you are trying to compile. If your makefile is generated by using autotools, use:

--prefix=<myinstalldir>

when running the ./configure

some packages allow you to also override when running:

make prefix=<myinstalldir>

however, if your not using ./configure, only way to know for sure is to open up the makefile and check. It should be one of the first few variables at the top.

What are Makefile.am and Makefile.in?

reference :

Makefile.am -- a user input file to automake

configure.in -- a user input file to autoconf


autoconf generates configure from configure.in

automake gererates Makefile.in from Makefile.am

configure generates Makefile from Makefile.in

For ex:

$]
configure.in Makefile.in
$] sudo autoconf
configure configure.in Makefile.in ... 
$] sudo ./configure
Makefile Makefile.in

error: Libtool library used but 'LIBTOOL' is undefined

For folks who ended up here and are using CYGWIN, install following packages in cygwin and re-run:

  • cygwin32-libtool
  • libtool
  • libtool-debuginfo

CFLAGS vs CPPFLAGS

To add to those who have mentioned the implicit rules, it's best to see what make has defined implicitly and for your env using:

make -p

For instance:

%.o: %.c
    $(COMPILE.c) $(OUTPUT_OPTION) $<

which expands

COMPILE.c = $(CXX) $(CXXFLAGS) $(CPPFLAGS) $(TARGET_ARCH) -c

This will also print # environment data. Here, you will find GCC's include path among other useful info.

C_INCLUDE_PATH=/usr/include

In make, when it comes to search, the paths are many, the light is one... or something to that effect.

  1. C_INCLUDE_PATH is system-wide, set it in your shell's *.rc.
  2. $(CPPFLAGS) is for the preprocessor include path.
  3. If you need to add a general search path for make, use:
VPATH = my_dir_to_search

... or even more specific

vpath %.c src
vpath %.h include

make uses VPATH as a general search path so use cautiously. If a file exists in more than one location listed in VPATH, make will take the first occurrence in the list.

Debugging the error "gcc: error: x86_64-linux-gnu-gcc: No such file or directory"

I was getting the error “gcc: error: x86_64-linux-gnu-gcc: No such file or directory” as I was trying to build a simple c-extension module to run in Python. I tried all the things above to no avail, and finally realized that I had an error in my module.c code! So I thought it would be helpful to add that, if you are getting this error message but you have python-dev and everything correctly installed, you should look for issues in your code.

How do I enable Java in Microsoft Edge web browser?

About this, java declares that on Windows 10, Edge browser does not support plugins, so it will NOT run java. (see https://www.java.com/it/download/win10.jsp --> only visible with edge in win10) It also reports a notice: java is not officially supported yet in Windows 10. (see https://www.java.com/it/download/faq/win10_faq.xml)

Why is document.body null in my javascript?

Add your code to the onload event. The accepted answer shows this correctly, however that answer as well as all the others at the time of writing also suggest putting the script tag after the closing body tag, .

This is not valid html. However it will cause your code to work, because browsers are too kind ;)

See this answer for more info Is it wrong to place the <script> tag after the </body> tag?

Downvoted other answers for this reason.

TCPDF ERROR: Some data has already been output, can't send PDF file

I just want to add that I was getting this error, and nothing would fix it until I changed the Output destination parameter from F to FI. In other words, I have to output to both file and inline.

Output('doc.pdf', 'I')

to

Output('doc.pdf', 'FI')

I have no idea why this made the difference, but it fixed the error for me...

How to use JUnit to test asynchronous processes

IMHO it's bad practice to have unit tests create or wait on threads, etc. You'd like these tests to run in split seconds. That's why I'd like to propose a 2-step approach to testing async processes.

  1. Test that your async process is submitted properly. You can mock the object that accepts your async requests and make sure that the submitted job has correct properties, etc.
  2. Test that your async callbacks are doing the right things. Here you can mock out the originally submitted job and assume it's initialized properly and verify that your callbacks are correct.

How to serve up images in Angular2?

Angular only points to src/assets folder, nothing else is public to access via url so you should use full path

 this.fullImagePath = '/assets/images/therealdealportfoliohero.jpg'

Or

 this.fullImagePath = 'assets/images/therealdealportfoliohero.jpg'

This will only work if the base href tag is set with /

You can also add other folders for data in angular/cli. All you need to modify is angular-cli.json

"assets": [
 "assets",
 "img",
 "favicon.ico",
 ".htaccess"
]

Note in edit : Dist command will try to find all attachments from assets so it is also important to keep the images and any files you want to access via url inside assets, like mock json data files should also be in assets.

VS 2012: Scroll Solution Explorer to current file

If you have ReSharper installed clicking Shift+Alt+L will move focus to the current file in Solution Explorer.

Active Item Tracking will also need to be enabled as described in the accepted answer

Tools->Options->Projects and Solutions->Track Active Item in Solution Explorer

IIS 7, HttpHandler and HTTP Error 500.21

I had the same problem and just solved it. I had posted my own question on stackoverflow:

Can't PUT to my IHttpHandler, GET works fine

The solution was to set runManagedModulesForWebDavRequests to true in the modules element. My guess is that once you install WebDAV then all PUT requests are associated with it. If you need the PUT to go to your handler, you need to remove the WebDAV module and set this attribute to true.

<modules runManagedModulesForWebDavRequests="true">
...
</modules>

So if you're running into the problem when you use the PUT verb and you have installed WebDAV then hopefully this solution will fix your problem.

Export from pandas to_excel without row names (index)?

You need to set index=False in to_excel in order for it to not write the index column out, this semantic is followed in other Pandas IO tools, see http://pandas.pydata.org/pandas-docs/stable/generated/pandas.DataFrame.to_excel.html and http://pandas.pydata.org/pandas-docs/stable/io.html

Adding horizontal spacing between divs in Bootstrap 3

The best solution is not to use the same element for column and panel:

<div class="row">
    <div class="col-md-3">
        <div class="panel" id="gameplay-away-team">Away Team</div>
    </div>
    <div class="col-md-6">
        <div class="panel" id="gameplay-baseball-field">Baseball Field</div>
    </div>
    <div class="col-md-3">
        <div class="panel" id="gameplay-home-team">Home Team</div>
    </div>
</div>

and some more styles:

#gameplay-baseball-field {
  padding-right: 10px;
  padding-left: 10px;
}

Wait until an HTML5 video loads

You don't really need jQuery for this as there is a Media API that provides you with all you need.

var video = document.getElementById('myVideo');
video.src = 'my_video_' + value + '.ogg';
video.load();

The Media API also contains a load() method which: "Causes the element to reset and start selecting and loading a new media resource from scratch."

(Ogg isn't the best format to use, as it's only supported by a limited number of browsers. I'd suggest using WebM and MP4 to cover all major browsers - you can use the canPlayType() function to decide on which one to play).

You can then wait for either the loadedmetadata or loadeddata (depending on what you want) events to fire:

video.addEventListener('loadeddata', function() {
   // Video is loaded and can be played
}, false);

How can I implement prepend and append with regular JavaScript?

Here's a snippet to get you going:

theParent = document.getElementById("theParent");
theKid = document.createElement("div");
theKid.innerHTML = 'Are we there yet?';

// append theKid to the end of theParent
theParent.appendChild(theKid);

// prepend theKid to the beginning of theParent
theParent.insertBefore(theKid, theParent.firstChild);

theParent.firstChild will give us a reference to the first element within theParent and put theKid before it.

Python function overloading

In Python 3.4 PEP-0443. Single-dispatch generic functions was added.

Here is a short API description from PEP.

To define a generic function, decorate it with the @singledispatch decorator. Note that the dispatch happens on the type of the first argument. Create your function accordingly:

from functools import singledispatch
@singledispatch
def fun(arg, verbose=False):
    if verbose:
        print("Let me just say,", end=" ")
    print(arg)

To add overloaded implementations to the function, use the register() attribute of the generic function. This is a decorator, taking a type parameter and decorating a function implementing the operation for that type:

@fun.register(int)
def _(arg, verbose=False):
    if verbose:
        print("Strength in numbers, eh?", end=" ")
    print(arg)

@fun.register(list)
def _(arg, verbose=False):
    if verbose:
        print("Enumerate this:")
    for i, elem in enumerate(arg):
        print(i, elem)

How do I start PowerShell from Windows Explorer?

There's a Windows Explorer extension made by the dude who makes tools for SVN that will at least open a command prompt window.

I haven't tried it yet, so I don't know if it'll do PowerShell, but I wanted to share the love with my Stack Overflow brethren:

http://tools.tortoisesvn.net/StExBar

How to use the curl command in PowerShell?

In Powershell 3.0 and above there is both a Invoke-WebRequest and Invoke-RestMethod. Curl is actually an alias of Invoke-WebRequest in PoSH. I think using native Powershell would be much more appropriate than curl, but it's up to you :).

Invoke-WebRequest MSDN docs are here: https://technet.microsoft.com/en-us/library/hh849901.aspx?f=255&MSPPError=-2147217396

Invoke-RestMethod MSDN docs are here: https://technet.microsoft.com/en-us/library/hh849971.aspx?f=255&MSPPError=-2147217396

How to detect if URL has changed after hash in JavaScript

Add a hash change event listener!

window.addEventListener('hashchange', function(e){console.log('hash changed')});

Or, to listen to all URL changes:

window.addEventListener('popstate', function(e){console.log('url changed')});

This is better than something like the code below because only one thing can exist in window.onhashchange and you'll possibly be overwriting someone else's code.

// Bad code example

window.onhashchange = function() { 
     // Code that overwrites whatever was previously in window.onhashchange  
}

Convert categorical data in pandas dataframe

This works for me:

pandas.factorize( ['B', 'C', 'D', 'B'] )[0]

Output:

[0, 1, 2, 0]

Should a 502 HTTP status code be used if a proxy receives no response at all?

Yes. Empty or incomplete headers or response body typically caused by broken connections or server side crash can cause 502 errors if accessed via a gateway or proxy.

For more information about the network errors

https://en.wikipedia.org/wiki/List_of_HTTP_status_codes

ADB not recognising Nexus 4 under Windows 7

To fix/install Android USB driver on Windows 7/8 32bit/64bit:

  1. Connect your Android-powered device to your computer's USB port.
  2. Right-click on Computer from your desktop or Windows Explorer, and select Manage.
  3. Select Devices in the left pane.
  4. Locate and expand Other device in the right pane.
  5. Right-click the device name (Nexus 7 / Nexus 5 / Nexus 4) and select Update Driver Software. This will launch the Hardware Update Wizard.
  6. Select Browse my computer for driver software and click Next.
  7. Click Browse and locate the USB driver folder. (The Google USB Driver is located in <sdk>\extras\google\usb_driver\.)
  8. Click Next to install the driver.

If it still doesn't work try changing from MTP to PTP.

MTP -> PTP

What is "origin" in Git?

The best answer here:

https://www.git-tower.com/learn/git/glossary/origin

In Git, "origin" is a shorthand name for the remote repository that a project was originally cloned from. More precisely, it is used instead of that original repository's URL - and thereby makes referencing much easier.

Django set default form values

Other solution: Set initial after creating the form:

form.fields['tank'].initial = 123

jQuery changing css class to div

$(".first").addClass("second");

If you'd like to add it on an event, you can do so easily as well. An example with the click event:

$(".first").click(function() {
    $(this).addClass("second");
});

How do I crop an image in Java?

This question has not enough information to answer. A general solution (depending on your GUI framework): add a mouse event handler that will catch clicks and mouse movements. This will give you your (x, y) coordinates. Next use these coordinates to crop your image.

Selected tab's color in Bottom Navigation View

Instead of creating selector, Best way to create a style.

<style name="AppTheme.BottomBar">
    <item name="colorPrimary">@color/colorAccent</item> 
</style>

and to change the text size, selected or non selected.

<dimen name="design_bottom_navigation_text_size" tools:override="true">11sp</dimen>
<dimen name="design_bottom_navigation_active_text_size" tools:override="true">12sp</dimen>

Enjoy Android!

Difference between "as $key => $value" and "as $value" in PHP foreach

A very important place where it is REQUIRED to use the key => value pair in foreach loop is to be mentioned. Suppose you would want to add a new/sub-element to an existing item (in another key) in the $features array. You should do the following:

foreach($features as $key => $feature) {
    $features[$key]['new_key'] = 'new value';  
} 


Instead of this:

foreach($features as $feature) {
    $feature['new_key'] = 'new value';  
} 

The big difference here is that, in the first case you are accessing the array's sub-value via the main array itself with a key to the element which is currently being pointed to by the array pointer.

While in the second (which doesn't work for this purpose) you are assigning the sub-value in the array to a temporary variable $feature which is unset after each loop iteration.

jQuery load more data on scroll

If not all of your document scrolls, say, when you have a scrolling div within the document, then the above solutions won't work without adaptations. Here's how to check whether the div's scrollbar has hit the bottom:

$('#someScrollingDiv').on('scroll', function() {
    let div = $(this).get(0);
    if(div.scrollTop + div.clientHeight >= div.scrollHeight) {
        // do the lazy loading here
    }
});

Cordova app not displaying correctly on iPhone X (Simulator)

Fix for iPhone X/XS screen rotation issue

On iPhone X/XS, a screen rotation will cause the header bar height to use an incorrect value, because the calculation of safe-area-inset-* was not reflecting the new values in time for UI refresh. This bug exists in UIWebView even in the latest iOS 12. A workaround is inserting a 1px top margin and then quickly reversing it, which will trigger safe-area-inset-* to be re-calculated immediately. A somewhat ugly fix but it works if you have to stay with UIWebView for one reason or another.

_x000D_
_x000D_
window.addEventListener("orientationchange", function() {_x000D_
    var originalMarginTop = document.body.style.marginTop;_x000D_
    document.body.style.marginTop = "1px";_x000D_
    setTimeout(function () {_x000D_
        document.body.style.marginTop = originalMarginTop;_x000D_
    }, 100);_x000D_
}, false);
_x000D_
_x000D_
_x000D_

The purpose of the code is to cause the document.body.style.marginTop to change slightly and then reverse it. It doesn't necessarily have to be "1px". You can pick a value that doesn't cause your UI to flicker but achieves its purpose.

Python + Regex: AttributeError: 'NoneType' object has no attribute 'groups'

You are getting AttributeError because you're calling groups on None, which hasn't any methods.

regex.search returning None means the regex couldn't find anything matching the pattern from supplied string.

when using regex, it is nice to check whether a match has been made:

Result = re.search(SearchStr, htmlString)

if Result:
    print Result.groups()

How to initailize byte array of 100 bytes in java with all 0's

Actually the default value of byte is 0.

7-zip commandline

I've not looked into this but shooting from the hip I'd say that they dropped command line support in the portable. The reason people don't do much command line stuff in portable applications is that the OS (windows in your case) requires that executables be added to the %path% inclusion list.

If that requirement is not met using command line utilities is rather tedious.

7z -a .

would be

d:\portable\z7\z7 -a c:\to\archive\folder*.*

Typing that out for everything is why GUI's make sense with things like portable apps it (the app) can remember it's own location and handle that stuff for you and if you can't run it you know it's not attached.

If you really want the portable app to contain that though you can always install the full version and pull the required 7z.exe out and put it into the portable folder making sure it's in with the required dll's.

You'll have to set your path when you hit the shell after making sure it's attached.

http://www.redfernplace.com/software-projects/patheditor/ -- a good path editor (down) usefull if you have lots of path information 20+ get's hard to read.

http://www.softpedia.com/get/System/System-Miscellaneous/Path-Editor.shtml -- alternet source for path editor

It's not advisable to modify your system path for temproary "portable" drives though manualy do that by:

set path=%path%;"d:\portable\z7\";

when you run dos cmd.exe or http://sourceforge.net/p/conemu/home/Home/

The other answers address other problems better I'm not going to try..

http://www.codejacked.com/zip-up-files-from-the-command-line/ -- good reference for command line usage of z7 and z7a.

PS: sorry for the necro but I figured it needed a more direct answer to why (even if it's just speculative).

Handling InterruptedException in Java

The correct default choice is add InterruptedException to your throws list. An Interrupt indicates that another thread wishes your thread to end. The reason for this request is not made evident and is entirely contextual, so if you don't have any additional knowledge you should assume it's just a friendly shutdown, and anything that avoids that shutdown is a non-friendly response.

Java will not randomly throw InterruptedException's, all advice will not affect your application but I have run into a case where developer's following the "swallow" strategy became very inconvenient. A team had developed a large set of tests and used Thread.Sleep a lot. Now we started to run the tests in our CI server, and sometimes due to defects in the code would get stuck into permanent waits. To make the situation worse, when attempting to cancel the CI job it never closed because the Thread.Interrupt that was intended to abort the test did not abort the job. We had to login to the box and manually kill the processes.

So long story short, if you simply throw the InterruptedException you are matching the default intent that your thread should end. If you can't add InterruptedException to your throw list, I'd wrap it in a RuntimeException.

There is a very rational argument to be made that InterruptedException should be a RuntimeException itself, since that would encourage a better "default" handling. It's not a RuntimeException only because the designers stuck to a categorical rule that a RuntimeException should represent an error in your code. Since an InterruptedException does not arise directly from an error in your code, it's not. But the reality is that often an InterruptedException arises because there is an error in your code, (i.e. endless loop, dead-lock), and the Interrupt is some other thread's method for dealing with that error.

If you know there is rational cleanup to be done, then do it. If you know a deeper cause for the Interrupt, you can take on more comprehensive handling.

So in summary your choices for handling should follow this list:

  1. By default, add to throws.
  2. If not allowed to add to throws, throw RuntimeException(e). (Best choice of multiple bad options)
  3. Only when you know an explicit cause of the Interrupt, handle as desired. If your handling is local to your method, then reset interrupted by a call to Thread.currentThread().interrupt().

How to return multiple rows from the stored procedure? (Oracle PL/SQL)

Here is how to build a function that returns a result set that can be queried as if it were a table:

SQL> create type emp_obj is object (empno number, ename varchar2(10));
  2  /

Type created.

SQL> create type emp_tab is table of emp_obj;
  2  /

Type created.

SQL> create or replace function all_emps return emp_tab
  2  is
  3     l_emp_tab emp_tab := emp_tab();
  4     n integer := 0;
  5  begin
  6     for r in (select empno, ename from emp)
  7     loop
  8        l_emp_tab.extend;
  9        n := n + 1;
 10       l_emp_tab(n) := emp_obj(r.empno, r.ename);
 11     end loop;
 12     return l_emp_tab;
 13  end;
 14  /

Function created.

SQL> select * from table (all_emps);

     EMPNO ENAME
---------- ----------
      7369 SMITH
      7499 ALLEN
      7521 WARD
      7566 JONES
      7654 MARTIN
      7698 BLAKE
      7782 CLARK
      7788 SCOTT
      7839 KING
      7844 TURNER
      7902 FORD
      7934 MILLER

Handle JSON Decode Error when nothing returned

There is a rule in Python programming called "it is Easier to Ask for Forgiveness than for Permission" (in short: EAFP). It means that you should catch exceptions instead of checking values for validity.

Thus, try the following:

try:
    qByUser = byUsrUrlObj.read()
    qUserData = json.loads(qByUser).decode('utf-8')
    questionSubjs = qUserData["all"]["questions"]
except ValueError:  # includes simplejson.decoder.JSONDecodeError
    print 'Decoding JSON has failed'

EDIT: Since simplejson.decoder.JSONDecodeError actually inherits from ValueError (proof here), I simplified the catch statement by just using ValueError.

Application Error - The connection to the server was unsuccessful. (file:///android_asset/www/index.html)

I had a similar issue and based on above suggestions I first added "super.setIntegerProperty("loadUrlTimeoutValue", 70000);" but that did not help. So I tried Project -> Clean, that worked and I can launch the app now !

Avinash...

Powershell folder size of folders without listing Subdirectories

You need to get the total contents size of each directory recursively to output. Also, you need to specify that the contents you're grabbing to measure are not directories, or you risk errors (as directories do not have a Length parameter).

Here's your script modified for the output you're looking for:

$colItems = Get-ChildItem $startFolder | Where-Object {$_.PSIsContainer -eq $true} | Sort-Object
foreach ($i in $colItems)
{
    $subFolderItems = Get-ChildItem $i.FullName -recurse -force | Where-Object {$_.PSIsContainer -eq $false} | Measure-Object -property Length -sum | Select-Object Sum
    $i.FullName + " -- " + "{0:N2}" -f ($subFolderItems.sum / 1MB) + " MB"
}

Iterator invalidation rules

C++17 (All references are from the final working draft of CPP17 - n4659)


Insertion

Sequence Containers

  • vector: The functions insert, emplace_back, emplace, push_back cause reallocation if the new size is greater than the old capacity. Reallocation invalidates all the references, pointers, and iterators referring to the elements in the sequence. If no reallocation happens, all the iterators and references before the insertion point remain valid. [26.3.11.5/1]
    With respect to the reserve function, reallocation invalidates all the references, pointers, and iterators referring to the elements in the sequence. No reallocation shall take place during insertions that happen after a call to reserve() until the time when an insertion would make the size of the vector greater than the value of capacity(). [26.3.11.3/6]

  • deque: An insertion in the middle of the deque invalidates all the iterators and references to elements of the deque. An insertion at either end of the deque invalidates all the iterators to the deque, but has no effect on the validity of references to elements of the deque. [26.3.8.4/1]

  • list: Does not affect the validity of iterators and references. If an exception is thrown there are no effects. [26.3.10.4/1].
    The insert, emplace_front, emplace_back, emplace, push_front, push_back functions are covered under this rule.

  • forward_list: None of the overloads of insert_after shall affect the validity of iterators and references [26.3.9.5/1]

  • array: As a rule, iterators to an array are never invalidated throughout the lifetime of the array. One should take note, however, that during swap, the iterator will continue to point to the same array element, and will thus change its value.

Associative Containers

  • All Associative Containers: The insert and emplace members shall not affect the validity of iterators and references to the container [26.2.6/9]

Unordered Associative Containers

  • All Unordered Associative Containers: Rehashing invalidates iterators, changes ordering between elements, and changes which buckets elements appear in, but does not invalidate pointers or references to elements. [26.2.7/9]
    The insert and emplace members shall not affect the validity of references to container elements, but may invalidate all iterators to the container. [26.2.7/14]
    The insert and emplace members shall not affect the validity of iterators if (N+n) <= z * B, where N is the number of elements in the container prior to the insert operation, n is the number of elements inserted, B is the container’s bucket count, and z is the container’s maximum load factor. [26.2.7/15]

  • All Unordered Associative Containers: In case of a merge operation (e.g., a.merge(a2)), iterators referring to the transferred elements and all iterators referring to a will be invalidated, but iterators to elements remaining in a2 will remain valid. (Table 91 — Unordered associative container requirements)

Container Adaptors

  • stack: inherited from underlying container
  • queue: inherited from underlying container
  • priority_queue: inherited from underlying container

Erasure

Sequence Containers

  • vector: The functions erase and pop_back invalidate iterators and references at or after the point of the erase. [26.3.11.5/3]

  • deque: An erase operation that erases the last element of a deque invalidates only the past-the-end iterator and all iterators and references to the erased elements. An erase operation that erases the first element of a deque but not the last element invalidates only iterators and references to the erased elements. An erase operation that erases neither the first element nor the last element of a deque invalidates the past-the-end iterator and all iterators and references to all the elements of the deque. [ Note: pop_front and pop_back are erase operations. —end note ] [26.3.8.4/4]

  • list: Invalidates only the iterators and references to the erased elements. [26.3.10.4/3]. This applies to erase, pop_front, pop_back, clear functions.
    remove and remove_if member functions: Erases all the elements in the list referred by a list iterator i for which the following conditions hold: *i == value, pred(*i) != false. Invalidates only the iterators and references to the erased elements [26.3.10.5/15].
    unique member function - Erases all but the first element from every consecutive group of equal elements referred to by the iterator i in the range [first + 1, last) for which *i == *(i-1) (for the version of unique with no arguments) or pred(*i, *(i - 1)) (for the version of unique with a predicate argument) holds. Invalidates only the iterators and references to the erased elements. [26.3.10.5/19]

  • forward_list: erase_after shall invalidate only iterators and references to the erased elements. [26.3.9.5/1].
    remove and remove_if member functions - Erases all the elements in the list referred by a list iterator i for which the following conditions hold: *i == value (for remove()), pred(*i) is true (for remove_if()). Invalidates only the iterators and references to the erased elements. [26.3.9.6/12].
    unique member function - Erases all but the first element from every consecutive group of equal elements referred to by the iterator i in the range [first + 1, last) for which *i == *(i-1) (for the version with no arguments) or pred(*i, *(i - 1)) (for the version with a predicate argument) holds. Invalidates only the iterators and references to the erased elements. [26.3.9.6/16]

  • All Sequence Containers: clear invalidates all references, pointers, and iterators referring to the elements of a and may invalidate the past-the-end iterator (Table 87 — Sequence container requirements). But for forward_list, clear does not invalidate past-the-end iterators. [26.3.9.5/32]

  • All Sequence Containers: assign invalidates all references, pointers and iterators referring to the elements of the container. For vector and deque, also invalidates the past-the-end iterator. (Table 87 — Sequence container requirements)

Associative Containers

  • All Associative Containers: The erase members shall invalidate only iterators and references to the erased elements [26.2.6/9]

  • All Associative Containers: The extract members invalidate only iterators to the removed element; pointers and references to the removed element remain valid [26.2.6/10]

Container Adaptors

  • stack: inherited from underlying container
  • queue: inherited from underlying container
  • priority_queue: inherited from underlying container

General container requirements relating to iterator invalidation:

  • Unless otherwise specified (either explicitly or by defining a function in terms of other functions), invoking a container member function or passing a container as an argument to a library function shall not invalidate iterators to, or change the values of, objects within that container. [26.2.1/12]

  • no swap() function invalidates any references, pointers, or iterators referring to the elements of the containers being swapped. [ Note: The end() iterator does not refer to any element, so it may be invalidated. —end note ] [26.2.1/(11.6)]

As examples of the above requirements:

  • transform algorithm: The op and binary_op functions shall not invalidate iterators or subranges, or modify elements in the ranges [28.6.4/1]

  • accumulate algorithm: In the range [first, last], binary_op shall neither modify elements nor invalidate iterators or subranges [29.8.2/1]

  • reduce algorithm: binary_op shall neither invalidate iterators or subranges, nor modify elements in the range [first, last]. [29.8.3/5]

and so on...

C# loop - break vs. continue

if you don't want to use break you just increase value of I in such a way that it make iteration condition false and loop will not execute on next iteration.

for(int i = 0; i < list.Count; i++){
   if(i == 5)
    i = list.Count;  //it will make "i<list.Count" false and loop will exit
}

Get total of Pandas column

There are two ways to sum of a column

dataset = pd.read_csv("data.csv")

1: sum(dataset.Column_name)

2: dataset['Column_Name'].sum()

If there is any issue in this the please correct me..

What does 'Unsupported major.minor version 52.0' mean, and how do I fix it?

Your code was compiled with Java 8.

Either compile your code with an older JDK (compliance level) or run it on a Java 8 JRE.

Hope this helps...

Fastest way to iterate over all the chars in a String

String.toCharArray() creates new char array, means allocation of memory of string length, then copies original char array of string using System.arraycopy() and then returns this copy to caller. String.charAt() returns character at position i from original copy, that's why String.charAt() will be faster than String.toCharArray(). Although, String.toCharArray() returns copy and not char from original String array, where String.charAt() returns character from original char array. Code below returns value at the specified index of this string.

public char charAt(int index) {
    if ((index < 0) || (index >= value.length)) {
        throw new StringIndexOutOfBoundsException(index);
    }
    return value[index];
}

code below returns a newly allocated character array whose length is the length of this string

public char[] toCharArray() {
    // Cannot use Arrays.copyOf because of class initialization order issues
    char result[] = new char[value.length];
    System.arraycopy(value, 0, result, 0, value.length);
    return result;
}

First char to upper case

userIdeaUC = userIdea.substring(0, 1).toUpperCase() + userIdea.length() > 1 ? userIdea.substring(1) : "";

or

userIdeaUC = userIdea.substring(0, 1).toUpperCase();
if(userIdea.length() > 1)
   userIdeaUC += userIdea.substring(1);

R color scatter plot points based on values

Here is a method using a lookup table of thresholds and associated colours to map the colours to the variable of interest.

 # make a grid 'Grd' of points and number points for side of square 'GrdD'
Grd <- expand.grid(seq(0.5,400.5,10),seq(0.5,400.5,10))
GrdD <- length(unique(Grd$Var1))

# Add z-values to the grid points
Grd$z <- rnorm(length(Grd$Var1), mean = 10, sd =2)

# Make a vector of thresholds 'Brks' to colour code z 
Brks <- c(seq(0,18,3),Inf)

# Make a vector of labels 'Lbls' for the colour threhsolds
Lbls <- Lbls <- c('0-3','3-6','6-9','9-12','12-15','15-18','>18')

# Make a vector of colours 'Clrs' for to match each range
Clrs <- c("grey50","dodgerblue","forestgreen","orange","red","purple","magenta")

# Make up lookup dataframe 'LkUp' of the lables and colours 
LkUp <- data.frame(cbind(Lbls,Clrs),stringsAsFactors = FALSE)

# Add a new variable 'Lbls' the grid dataframe mapping the labels based on z-value
Grd$Lbls <- as.character(cut(Grd$z, breaks = Brks, labels = Lbls))

# Add a new variable 'Clrs' to the grid dataframe based on the Lbls field in the grid and lookup table
Grd <- merge(Grd,LkUp, by.x = 'Lbls')

# Plot the grid using the 'Clrs' field for the colour of each point
plot(Grd$Var1,
     Grd$Var2,
     xlim = c(0,400),
     ylim = c(0,400),
     cex = 1.0,
     col = Grd$Clrs,
     pch = 20,
     xlab = 'mX',
     ylab = 'mY',
     main = 'My Grid',
     axes = FALSE,
     labels = FALSE,
     las = 1
)

axis(1,seq(0,400,100))
axis(2,seq(0,400,100),las = 1)
box(col = 'black')

legend("topleft", legend = Lbls, fill = Clrs, title = 'Z')

Django upgrading to 1.9 error "AppRegistryNotReady: Apps aren't loaded yet."

In my case one of my settings, 'CORS_ORIGIN_WHITELIST' was set in the settings.py file but was not available in my .env file. So I'll suggest that you check your settings, especially those linked to .env

How to convert image into byte array and byte array to base64 String in android?

Try this simple solution to convert file to base64 string

String base64String = imageFileToByte(file);

public String imageFileToByte(File file){

    Bitmap bm = BitmapFactory.decodeFile(file.getAbsolutePath());
    ByteArrayOutputStream baos = new ByteArrayOutputStream();
    bm.compress(Bitmap.CompressFormat.JPEG, 100, baos); //bm is the bitmap object
    byte[] b = baos.toByteArray();
    return Base64.encodeToString(b, Base64.DEFAULT);
}

Get CPU Usage from Windows Command Prompt

typeperf gives me issues when it randomly doesn't work on some computers (Error: No valid counters.) or if the account has insufficient rights. Otherwise, here is a way to extract just the value from its output. It still needs rounding though:

@for /f "delims=, tokens=2" %p in ('typeperf "\Processor(_Total)\% Processor Time" -sc 3 ^| find ":"') do @echo %~p%

Powershell has two cmdlets to get the percent utilization for all CPUs: Get-Counter (preferred) or Get-WmiObject:

Powershell "Get-Counter '\Processor(*)\% Processor Time' | Select -Expand Countersamples | Select InstanceName, CookedValue"

Or,

Powershell "Get-WmiObject Win32_PerfFormattedData_PerfOS_Processor | Select Name, PercentProcessorTime"


To get the overall CPU load with formatted output exactly like the question:

Powershell "[string][int](Get-Counter '\Processor(*)\% Processor Time').Countersamples[0].CookedValue + '%'"

Or,

 Powershell "gwmi Win32_PerfFormattedData_PerfOS_Processor | Select -First 1 | %{'{0}%' -f $_.PercentProcessorTime}"

Import Libraries in Eclipse?

Extract the jar, and put it somewhere in your Java project (usually under a "lib" subdirectory).

Right click the project, open its preferences, go for Java build path, and then the Libraries tab. You can add the library there with "add a jar".

If your jar is not open source, you may want to store it elsewhere and connect to it as an external jar.

How do I grep for all non-ASCII characters?

The following code works:

find /tmp | perl -ne 'print if /[^[:ascii:]]/'

Replace /tmp with the name of the directory you want to search through.

Build error: "The process cannot access the file because it is being used by another process"

In my case there were some vstest processes running (with various names but all containing the string vstest). I had to terminate them in taskmgr.

Heap space out of memory

Java is supposed to clear the heap space for you when all of the objects are no longer referenced. It won't generally release it back to the OS though, it will keep that memory for it's own internal reuse. Maybe check to see if you have some arrays which are not being cleared or something.

How to create a Java cron job

You can use TimerTask for Cronjobs.

Main.java

public class Main{
   public static void main(String[] args){

     Timer t = new Timer();
     MyTask mTask = new MyTask();
     // This task is scheduled to run every 10 seconds

     t.scheduleAtFixedRate(mTask, 0, 10000);
   }

}

MyTask.java

class MyTask extends TimerTask{

   public MyTask(){
     //Some stuffs
   }

   @Override
   public void run() {
     System.out.println("Hi see you after 10 seconds");
   }

}

Alternative You can also use ScheduledExecutorService.

How do I make a branch point at a specific commit?

git branch -f <branchname> <commit>

I go with Mark Longair's solution and comments and recommend anyone reads those before acting, but I'd suggest the emphasis should be on

git branch -f <branchname> <commit>

Here is a scenario where I have needed to do this.

Scenario

Develop on the wrong branch and hence need to reset it.

Start Okay

Cleanly develop and release some software.

So far so good

Develop on wrong branch

Mistake: Accidentally stay on the release branch while developing further.

After a mistake

Realize the mistake

"OH NO! I accidentally developed on the release branch." The workspace is maybe cluttered with half changed files that represent work-in-progress and we really don't want to touch and mess with. We'd just like git to flip a few pointers to keep track of the current state and put that release branch back how it should be.

Create a branch for the development that is up to date holding the work committed so far and switch to it.

git branch development
git checkout development 

Changed to another branch

Correct the branch

Now we are in the problem situation and need its solution! Rectify the mistake (of taking the release branch forward with the development) and put the release branch back how it should be.

Correct the release branch to point back to the last real release.

git branch -f release release2

The release branch is now correct again, like this ...

Corrected

What if I pushed the mistake to a remote?

git push -f <remote> <branch> is well described in another thread, though the word "overwrite" in the title is misleading. Force "git push" to overwrite remote files

password-check directive in angularjs

This works both ways and it is simple and clean

JavaScript

var app = angular.module("app");

app.controller("SamePaswordController", function () {

  this.password;
  this.confirm;

  this.save = function () {
    alert("Saved!");
  };
}


app.directive("match", function () {
  return {
    restrict:"A",
    require:"ngModel",

    link: function(scope, element, attrs, ctrl) {

      function matchValidator(value) {      

        scope.$watch(attrs.match, function(newValue, oldValue) {

          var isValid = value === scope.$eval(attrs.match);                    
          ctrl.$setValidity('match', isValid);

        });

        return value;
      }

      ctrl.$parsers.push(matchValidator);
    }
  };
});

HTML: note the match directive

<form name="regForm" ng-controller="SamePaswordController as regCtrl"
      ng-submit="regForm.$valid && regCtrl.save()" novalidate>

  <input name="password" ng-model="regCtrl.password" 
         type="password" required placeholder="Password"/>                

  <input name="confirm" ng-model="regCtrl.confirm" match="regCtrl.password"
         type="password" required placeholder="Confirm password"/>


  <div> regForm is valid:{{regForm.$valid}}</div>

  <input type="submit" value="Save"/>

</form>

You can clone the repo with this example https://github.com/rogithub/roangularjs

Resize to fit image in div, and center horizontally and vertically

NOT SUPPORTED BY IE

More info here: Can I Use?

_x000D_
_x000D_
.container {_x000D_
  overflow: hidden;_x000D_
  width: 100px;_x000D_
  height: 100px;_x000D_
}_x000D_
_x000D_
.container img {_x000D_
  object-fit: cover;_x000D_
  width: 100%;_x000D_
  min-height: 100%;_x000D_
}
_x000D_
<div class='container'>_x000D_
    <img src='http://i.imgur.com/H9lpVkZ.jpg' />_x000D_
</div>
_x000D_
_x000D_
_x000D_

Two submit buttons in one form

Since you didn't specify what server-side scripting method you're using, I'll give you an example that works for Python, using CherryPy (although it may be useful for other contexts, too):

<button type="submit" name="register">Create a new account</button>
<button type="submit" name="login">Log into your account</button>

Rather than using the value to determine which button was pressed, you can use the name (with the <button> tag instead of <input>). That way, if your buttons happen to have the same text, it won't cause problems. The names of all form items, including buttons, are sent as part of the URL. In CherryPy, each of those is an argument for a method that does the server-side code. So, if your method just has **kwargs for its parameter list (instead of tediously typing out every single name of each form item) then you can check to see which button was pressed like this:

if "register" in kwargs:
    pass #Do the register code
elif "login" in kwargs:
    pass #Do the login code

How to change the session timeout in PHP?

Just a notice for a sharing hosting server or added on domains =

For your settings to work you must have a different save session dir for added domain by using php_value session.save_path folderA/sessionsA.

So create a folder to your root server, not into the public_html and not to be publicity accessed from outside. For my cpanel/server worked fine the folder permissions 0700. Give a try...

# Session timeout, 2628000 sec = 1 month, 604800 = 1 week, 57600 = 16 hours, 86400 = 1 day
ini_set('session.save_path', '/home/server/.folderA_sessionsA');
ini_set('session.gc_maxlifetime', 57600); 
ini_set('session.cookie_lifetime', 57600);
# session.cache_expire is in minutes unlike the other settings above         
ini_set('session.cache_expire', 960);
ini_set('session.name', 'MyDomainA');

before session_start();

or put this in your .htaccess file.

php_value session.save_path /home/server/.folderA_sessionsA
php_value session.gc_maxlifetime 57600
php_value session.cookie_lifetime 57600
php_value session.cache_expire 57600
php_value session.name MyDomainA

After many researching and testing this worked fine for shared cpanel/php7 server. Many thanks to: NoiS

Check whether a path is valid in Python without creating a file at the path's target

try os.path.exists this will check for the path and return True if exists and False if not.

Generics/templates in python?

Because Python is dynamically typed, the types of the objects don't matter in many cases. It's a better idea to accept anything.

To demonstrate what I mean, this tree class will accept anything for its two branches:

class BinaryTree:
    def __init__(self, left, right):
        self.left, self.right = left, right

And it could be used like this:

branch1 = BinaryTree(1,2)
myitem = MyClass()
branch2 = BinaryTree(myitem, None)
tree = BinaryTree(branch1, branch2)

Elegant Python function to convert CamelCase to snake_case?

There's an inflection library in the package index that can handle these things for you. In this case, you'd be looking for inflection.underscore():

>>> inflection.underscore('CamelCase')
'camel_case'

How to define servlet filter order of execution using annotations in WAR

The Servlet 3.0 spec doesn't seem to provide a hint on how a container should order filters that have been declared via annotations. It is clear how about how to order filters via their declaration in the web.xml file, though.

Be safe. Use the web.xml file order filters that have interdependencies. Try to make your filters all order independent to minimize the need to use a web.xml file.

IBOutlet and IBAction

IBAction and IBOutlets are used to hook up your interface made in Interface Builder with your controller. If you wouldn't use Interface Builder and build your interface completely in code, you could make a program without using them. But in reality most of us use Interface Builder, once you want to get some interactivity going in your interface, you will have to use IBActions and IBoutlets.

cannot load such file -- bundler/setup (LoadError)

I had almost precisely the same error, and was able to completely fix it simply by running:

gem install bundler

It's possible your bundler installation is corrupt or missing - that's what happened in my case. Note that if the above fails you can try:

sudo gem install bundler

...but generally you can do it without sudo.

How to use zIndex in react-native

Use elevation instead of zIndex for android devices

elevatedElement: {
  zIndex: 3, // works on ios
  elevation: 3, // works on android
}

This worked fine for me!

Getting a 500 Internal Server Error on Laravel 5+ Ubuntu 14.04

I read all the comments and suggestions. 500 - HTTP ERROR CODE represents internal server error.

Reasons for this error:

  • These mainly cause due to permission issues
  • Environment variables not found or .env file not found on your root directory
  • PHP extensions problem
  • Database problem

Fix:

  • Set the correct permissions:
  • Run these commands (Ubuntu/Debian)
find /path/to/your/root/dir/ -type f -exec chmod 644 {} \;
find /path/to/your/root/dir/ -type d -exec chmod 755 {} \;

chown -R www-data:www-data /path/to/your/root/dir/

chgrp -R www-data storage bootstrap/cache
chmod -R ug+rwx storage bootstrap/cache
  • If .env file doesn't exist, create one by touch .env and paste your environment variables and then run
   php artisan key:generate
   php artisan cache:clear
   php artisan config:clear
   composer dump-autoload
  • Check your php.ini file and uncomment the extensions you need (In some case you have to install the extension by running this command apt-get install php7.2-[extension-name]
  • Check your database credentials and values in .env file. And grant permissions to the database user for that database.

These are some common problem you likely going to face when deploying your laravel app and once you start getting all these commands, I suggest you to make a script which will save your time.

How can I use PHP to dynamically publish an ical file to be read by Google Calendar?

http://www.kanzaki.com/docs/ical/ has a slightly more readable version of the older spec. It helps as a starting point - many things are still the same.

Also on my site, I have

  1. Some lists of useful resources (see sidebar bottom right) on
    • ical Spec RFC 5545
    • ical Testing Resources
  2. Some notes recorded on my journey working with .ics over the last few years. In particular, you may find this repeating events 'cheatsheet' to be useful.

.ics areas that need careful handling:

  • 'all day' events
  • types of dates (timezone, UTC, or local 'floating') - nb to understand distinction
  • interoperability of recurrence rules

How to use pagination on HTML tables?

For me, best and simplest way, Bootply http://www.bootply.com/lxa0FF9yhw#

First include Bootstrap to your project

Then include javascript file in which you write this code:

    $.fn.pageMe = function(opts){
    var $this = this,
        defaults = {
            perPage: 7,
            showPrevNext: false,
            hidePageNumbers: false
        },
        settings = $.extend(defaults, opts);

    var listElement = $this;
    var perPage = settings.perPage; 
    var children = listElement.children();
    var pager = $('.pager');

    if (typeof settings.childSelector!="undefined") {
        children = listElement.find(settings.childSelector);
    }

    if (typeof settings.pagerSelector!="undefined") {
        pager = $(settings.pagerSelector);
    }

    var numItems = children.size();
    var numPages = Math.ceil(numItems/perPage);

    pager.data("curr",0);

    if (settings.showPrevNext){
        $('<li><a href="#" class="prev_link">«</a></li>').appendTo(pager);
    }

    var curr = 0;
    while(numPages > curr && (settings.hidePageNumbers==false)){
        $('<li><a href="#" class="page_link">'+(curr+1)+'</a></li>').appendTo(pager);
        curr++;
    }

    if (settings.showPrevNext){
        $('<li><a href="#" class="next_link">»</a></li>').appendTo(pager);
    }

    pager.find('.page_link:first').addClass('active');
    pager.find('.prev_link').hide();
    if (numPages<=1) {
        pager.find('.next_link').hide();
    }
    pager.children().eq(1).addClass("active");

    children.hide();
    children.slice(0, perPage).show();

    pager.find('li .page_link').click(function(){
        var clickedPage = $(this).html().valueOf()-1;
        goTo(clickedPage,perPage);
        return false;
    });
    pager.find('li .prev_link').click(function(){
        previous();
        return false;
    });
    pager.find('li .next_link').click(function(){
        next();
        return false;
    });

    function previous(){
        var goToPage = parseInt(pager.data("curr")) - 1;
        goTo(goToPage);
    }

    function next(){
        goToPage = parseInt(pager.data("curr")) + 1;
        goTo(goToPage);
    }

    function goTo(page){
        var startAt = page * perPage,
            endOn = startAt + perPage;

        children.css('display','none').slice(startAt, endOn).show();

        if (page>=1) {
            pager.find('.prev_link').show();
        }
        else {
            pager.find('.prev_link').hide();
        }

        if (page<(numPages-1)) {
            pager.find('.next_link').show();
        }
        else {
            pager.find('.next_link').hide();
        }

        pager.data("curr",page);
        pager.children().removeClass("active");
        pager.children().eq(page+1).addClass("active");

    }
};

You need to give an id to the tbody of your table and to add a 'div' after the table for the pagination

     <table class="table" id="myTable">
            <thead>
                <tr>
                    <th>...</th>
                </tr>
            </thead>
            <tbody id="myTableBody">
            </tbody>
       </table>
       <div class="col-md-12 text-center">
           <ul class="pagination pagination-lg pager" id="myPager"></ul>
       </div>

When your table's data is loaded, just call this

$('#myTableBody').pageMe({pagerSelector:'#myPager',showPrevNext:true,hidePageNumbers:false,perPage:4});

where the 'perPage' value is to set how many elements per page you want to have.

Python: OSError: [Errno 2] No such file or directory: ''

Have you noticed that you don't get the error if you run

python ./script.py

instead of

python script.py

This is because sys.argv[0] will read ./script.py in the former case, which gives os.path.dirname something to work with. When you don't specify a path, sys.argv[0] reads simply script.py, and os.path.dirname cannot determine a path.

What is the difference between an expression and a statement in Python?

STATEMENT:

A Statement is a action or a command that does something. Ex: If-Else,Loops..etc

val a: Int = 5
If(a>5) print("Hey!") else print("Hi!")

EXPRESSION:

A Expression is a combination of values, operators and literals which yields something.

val a: Int = 5 + 5 #yields 10

Datatype for storing ip address in SQL Server

Thanks RBarry. I'm putting together an IP block allocation system and storing as binary is the only way to go.

I'm storing the CIDR representation (ex: 192.168.1.0/24) of the IP block in a varchar field, and using 2 calculated fields to hold the binary form of the start and end of the block. From there, I can run fast queries to see if a given block as already been allocated or is free to assign.

I modified your function to calculate the ending IP Address like so:

CREATE FUNCTION dbo.fnDisplayIPv4End(@block AS VARCHAR(18)) RETURNS BINARY(4)
AS
BEGIN
    DECLARE @bin AS BINARY(4)
    DECLARE @ip AS VARCHAR(15)
    DECLARE @size AS INT

    SELECT @ip = Left(@block, Len(@block)-3)
    SELECT @size = Right(@block, 2)

    SELECT @bin = CAST( CAST( PARSENAME( @ip, 4 ) AS INTEGER) AS BINARY(1))
                + CAST( CAST( PARSENAME( @ip, 3 ) AS INTEGER) AS BINARY(1))
                + CAST( CAST( PARSENAME( @ip, 2 ) AS INTEGER) AS BINARY(1))
                + CAST( CAST( PARSENAME( @ip, 1 ) AS INTEGER) AS BINARY(1))

    SELECT @bin = CAST(@bin + POWER(2, 32-@size) AS BINARY(4))
    RETURN @bin
END;
go

Aligning rotated xticklabels with their respective xticks

An easy, loop-free alternative is to use the horizontalalignment Text property as a keyword argument to xticks[1]. In the below, at the commented line, I've forced the xticks alignment to be "right".

n=5
x = np.arange(n)
y = np.sin(np.linspace(-3,3,n))
xlabels = ['Long ticklabel %i' % i for i in range(n)]
fig, ax = plt.subplots()
ax.plot(x,y, 'o-')

plt.xticks(
        [0,1,2,3,4],
        ["this label extends way past the figure's left boundary",
        "bad motorfinger", "green", "in the age of octopus diplomacy", "x"], 
        rotation=45,
        horizontalalignment="right")    # here
plt.show()

(yticks already aligns the right edge with the tick by default, but for xticks the default appears to be "center".)

[1] You find that described in the xticks documentation if you search for the phrase "Text properties".

Using PowerShell credentials without being prompted for a password

why dont you try something very simple?

use psexec with command 'shutdown /r /f /t 0' and a PC list from CMD.

jQuery slide left and show

Don't forget the padding and margins...

jQuery.fn.slideLeftHide = function(speed, callback) { 
  this.animate({ 
    width: "hide", 
    paddingLeft: "hide", 
    paddingRight: "hide", 
    marginLeft: "hide", 
    marginRight: "hide" 
  }, speed, callback);
}

jQuery.fn.slideLeftShow = function(speed, callback) { 
  this.animate({ 
    width: "show", 
    paddingLeft: "show", 
    paddingRight: "show", 
    marginLeft: "show", 
    marginRight: "show" 
  }, speed, callback);
}

With the speed/callback arguments added, it's a complete drop-in replacement for slideUp() and slideDown().

I have never set any passwords to my keystore and alias, so how are they created?

Keystore name: "debug.keystore"

Keystore password: "android"

Key alias: "androiddebugkey"

Key password: "android"

I use this information and successfully generate Signed APK.

angularjs getting previous route path

@andresh For me locationChangeSuccess worked instead of routeChangeSuccess.

//Go back to the previous stage with this back() call
var history = [];
$rootScope.$on('$locationChangeSuccess', function() {
    history.push($location.$$path);
});

$rootScope.back = function () {
          var prevUrl = history.length > 1 ? history.splice(-2)[0] : "/";
          $location.path(prevUrl);
          history = []; //Delete history array after going back
      };

Remove Backslashes from Json Data in JavaScript

In React Native , This worked for me

name = "hi \n\ruser"
name.replace( /[\r\n]+/gm, ""); // hi user

Deprecated: mysql_connect()

There are a few solutions to your problem.

The way with MySQLi would be like this:

<?php
$connection = mysqli_connect('localhost', 'username', 'password', 'database');

To run database queries is also simple and nearly identical with the old way:

<?php
// Old way
mysql_query('CREATE TEMPORARY TABLE `table`', $connection);
// New way
mysqli_query($connection, 'CREATE TEMPORARY TABLE `table`');

Turn off all deprecated warnings including them from mysql_*:

<?php
error_reporting(E_ALL ^ E_DEPRECATED);

The Exact file and line location which needs to be replaced is "/System/Startup.php > line: 2 " error_reporting(E_All); replace with error_reporting(E_ALL ^ E_DEPRECATED);

How to print something when running Puppet client?

You could go a step further and break into the puppet code using a breakpoint.

http://logicminds.github.io/blog/2017/04/25/break-into-your-puppet-code/

This would only work with puppet apply or using a rspec test. Or you can manually type your code into the debugger console. Note: puppet still needs to know where your module code is at if you haven't set already.

gem install puppet puppet-debugger 
puppet module install nwops/debug
cat > test.pp <<'EOF'
$var1 = 'test'
debug::break()
EOF

Should show something like.

puppet apply test.pp
From file: test.pp
     1: $var1 = 'test'
     2: # add 'debug::break()' where you want to stop in your code
  => 3: debug::break()
1:>> $var1
=> "test"
2:>>

https://www.puppet-debugger.com

How to change the colors of a PNG image easily?

This should be fairly straightforward in the gimp http://gimp.org/

First make sure your image is RGB (not indexed color) then use the "color to alpha" feature to turn the clubs/diamonds clear, then fill or set the background or whatever to get the color you want.

Resizing Images in VB.NET

This will re-size any image using the best quality with support for 32bpp with alpha. The new image will have the original image centered inside the new one at the original aspect ratio.

#Region " ResizeImage "
    Public Overloads Shared Function ResizeImage(SourceImage As Drawing.Image, TargetWidth As Int32, TargetHeight As Int32) As Drawing.Bitmap
        Dim bmSource = New Drawing.Bitmap(SourceImage)

        Return ResizeImage(bmSource, TargetWidth, TargetHeight)
    End Function

    Public Overloads Shared Function ResizeImage(bmSource As Drawing.Bitmap, TargetWidth As Int32, TargetHeight As Int32) As Drawing.Bitmap
        Dim bmDest As New Drawing.Bitmap(TargetWidth, TargetHeight, Drawing.Imaging.PixelFormat.Format32bppArgb)

        Dim nSourceAspectRatio = bmSource.Width / bmSource.Height
        Dim nDestAspectRatio = bmDest.Width / bmDest.Height

        Dim NewX = 0
        Dim NewY = 0
        Dim NewWidth = bmDest.Width
        Dim NewHeight = bmDest.Height

        If nDestAspectRatio = nSourceAspectRatio Then
            'same ratio
        ElseIf nDestAspectRatio > nSourceAspectRatio Then
            'Source is taller
            NewWidth = Convert.ToInt32(Math.Floor(nSourceAspectRatio * NewHeight))
            NewX = Convert.ToInt32(Math.Floor((bmDest.Width - NewWidth) / 2))
        Else
            'Source is wider
            NewHeight = Convert.ToInt32(Math.Floor((1 / nSourceAspectRatio) * NewWidth))
            NewY = Convert.ToInt32(Math.Floor((bmDest.Height - NewHeight) / 2))
        End If

        Using grDest = Drawing.Graphics.FromImage(bmDest)
            With grDest
                .CompositingQuality = Drawing.Drawing2D.CompositingQuality.HighQuality
                .InterpolationMode = Drawing.Drawing2D.InterpolationMode.HighQualityBicubic
                .PixelOffsetMode = Drawing.Drawing2D.PixelOffsetMode.HighQuality
                .SmoothingMode = Drawing.Drawing2D.SmoothingMode.AntiAlias
                .CompositingMode = Drawing.Drawing2D.CompositingMode.SourceOver

                .DrawImage(bmSource, NewX, NewY, NewWidth, NewHeight)
            End With
        End Using

        Return bmDest
    End Function
#End Region

How do I bind a WPF DataGrid to a variable number of columns?

Here's a workaround for Binding Columns in the DataGrid. Since the Columns property is ReadOnly, like everyone noticed, I made an Attached Property called BindableColumns which updates the Columns in the DataGrid everytime the collection changes through the CollectionChanged event.

If we have this Collection of DataGridColumn's

public ObservableCollection<DataGridColumn> ColumnCollection
{
    get;
    private set;
}

Then we can bind BindableColumns to the ColumnCollection like this

<DataGrid Name="dataGrid"
          local:DataGridColumnsBehavior.BindableColumns="{Binding ColumnCollection}"
          AutoGenerateColumns="False"
          ...>

The Attached Property BindableColumns

public class DataGridColumnsBehavior
{
    public static readonly DependencyProperty BindableColumnsProperty =
        DependencyProperty.RegisterAttached("BindableColumns",
                                            typeof(ObservableCollection<DataGridColumn>),
                                            typeof(DataGridColumnsBehavior),
                                            new UIPropertyMetadata(null, BindableColumnsPropertyChanged));
    private static void BindableColumnsPropertyChanged(DependencyObject source, DependencyPropertyChangedEventArgs e)
    {
        DataGrid dataGrid = source as DataGrid;
        ObservableCollection<DataGridColumn> columns = e.NewValue as ObservableCollection<DataGridColumn>;
        dataGrid.Columns.Clear();
        if (columns == null)
        {
            return;
        }
        foreach (DataGridColumn column in columns)
        {
            dataGrid.Columns.Add(column);
        }
        columns.CollectionChanged += (sender, e2) =>
        {
            NotifyCollectionChangedEventArgs ne = e2 as NotifyCollectionChangedEventArgs;
            if (ne.Action == NotifyCollectionChangedAction.Reset)
            {
                dataGrid.Columns.Clear();
                foreach (DataGridColumn column in ne.NewItems)
                {
                    dataGrid.Columns.Add(column);
                }
            }
            else if (ne.Action == NotifyCollectionChangedAction.Add)
            {
                foreach (DataGridColumn column in ne.NewItems)
                {
                    dataGrid.Columns.Add(column);
                }
            }
            else if (ne.Action == NotifyCollectionChangedAction.Move)
            {
                dataGrid.Columns.Move(ne.OldStartingIndex, ne.NewStartingIndex);
            }
            else if (ne.Action == NotifyCollectionChangedAction.Remove)
            {
                foreach (DataGridColumn column in ne.OldItems)
                {
                    dataGrid.Columns.Remove(column);
                }
            }
            else if (ne.Action == NotifyCollectionChangedAction.Replace)
            {
                dataGrid.Columns[ne.NewStartingIndex] = ne.NewItems[0] as DataGridColumn;
            }
        };
    }
    public static void SetBindableColumns(DependencyObject element, ObservableCollection<DataGridColumn> value)
    {
        element.SetValue(BindableColumnsProperty, value);
    }
    public static ObservableCollection<DataGridColumn> GetBindableColumns(DependencyObject element)
    {
        return (ObservableCollection<DataGridColumn>)element.GetValue(BindableColumnsProperty);
    }
}

How to fill in form field, and submit, using javascript?

This method helped me doing this task

document.forms['YourFormNameHere'].elements['NameofFormField'].value = "YourValue"
document.forms['YourFormNameHere'].submit();

$(window).scrollTop() vs. $(document).scrollTop()

They are both going to have the same effect.

However, as pointed out in the comments: $(window).scrollTop() is supported by more web browsers than $('html').scrollTop().

Sort a List of objects by multiple fields

If you know in advance which fields to use to make the comparison, then other people gave right answers.
What you may be interested in is to sort your collection in case you don't know at compile-time which criteria to apply. Imagine you have a program dealing with cities:



    protected Set<City> cities;
    (...)
    Field temperatureField = City.class.getDeclaredField("temperature");
    Field numberOfInhabitantsField = City.class.getDeclaredField("numberOfInhabitants");
    Field rainfallField = City.class.getDeclaredField("rainfall");
    program.showCitiesSortBy(temperatureField, numberOfInhabitantsField, rainfallField);
    (...)
    public void showCitiesSortBy(Field... fields) {
        List<City> sortedCities = new ArrayList<City>(cities);
        Collections.sort(sortedCities, new City.CityMultiComparator(fields));
        for (City city : sortedCities) {
            System.out.println(city.toString());
        }
    }

where you can replace hard-coded field names by field names deduced from a user request in your program.

In this example, City.CityMultiComparator<City> is a static nested class of class City implementing Comparator:



    public static class CityMultiComparator implements Comparator<City> {
        protected List<Field> fields;

        public CityMultiComparator(Field... orderedFields) {
            fields = new ArrayList<Field>();
            for (Field field : orderedFields) {
                fields.add(field);
            }
        }

        @Override
        public int compare(City cityA, City cityB) {
            Integer score = 0;
            Boolean continueComparison = true;
            Iterator itFields = fields.iterator();

            while (itFields.hasNext() && continueComparison) {
                Field field = itFields.next();
                Integer currentScore = 0;
                if (field.getName().equalsIgnoreCase("temperature")) {
                    currentScore = cityA.getTemperature().compareTo(cityB.getTemperature());
                } else if (field.getName().equalsIgnoreCase("numberOfInhabitants")) {
                    currentScore = cityA.getNumberOfInhabitants().compareTo(cityB.getNumberOfInhabitants());
                } else if (field.getName().equalsIgnoreCase("rainfall")) {
                    currentScore = cityA.getRainfall().compareTo(cityB.getRainfall());
                }
                if (currentScore != 0) {
                    continueComparison = false;
                }
                score = currentScore;
            }

            return score;
        }
    }


You may want to add an extra layer of precision, to specify, for each field, whether sorting should be ascendant or descendant. I guess a solution is to replace Field objects by objects of a class you could call SortedField, containing a Field object, plus another field meaning ascendant or descendant.

Can someone explain how to append an element to an array in C programming?

Short answer is: You don't have any choice other than:

arr[4] = 5;

How to apply multiple transforms in CSS?

You can apply more than one transform like this:

li:nth-of-type(2){
    transform : translate(-20px, 0px) rotate(15deg);
}

Undefined reference to sqrt (or other mathematical functions)

Just adding the #include <math.h> in c source file and -lm in Makefile at the end will work for me.

    gcc -pthread -o p3 p3.c -lm

How to write a simple Java program that finds the greatest common divisor between two numbers?

You can also do it in a three line method:

public static int gcd(int x, int y){
  return (y == 0) ? x : gcd(y, x % y);
}

Here, if y = 0, x is returned. Otherwise, the gcd method is called again, with different parameter values.

Laravel 4: Redirect to a given url

You can use different types of redirect method in laravel -

return redirect()->intended('http://heera.it');

OR

return redirect()->to('http://heera.it');

OR

use Illuminate\Support\Facades\Redirect;

return Redirect::to('/')->with(['type' => 'error','message' => 'Your message'])->withInput(Input::except('password'));

OR

return redirect('/')->with(Auth::logout());

OR

return redirect()->route('user.profile', ['step' => $step, 'id' => $id]);

What values for checked and selected are false?

No value is considered false, only the absence of the attribute. There are plenty of invalid values though, and some implementations might consider certain invalid values as false.

HTML5 spec

http://www.w3.org/TR/html5/forms.html#attr-input-checked :

The disabled content attribute is a boolean attribute.

http://www.w3.org/TR/html5/infrastructure.html#boolean-attributes :

The presence of a boolean attribute on an element represents the true value, and the absence of the attribute represents the false value.

If the attribute is present, its value must either be the empty string or a value that is an ASCII case-insensitive match for the attribute's canonical name, with no leading or trailing whitespace.

Conclusion

The following are valid, equivalent and true:

<input type="checkbox" checked />
<input type="checkbox" checked="" />
<input type="checkbox" checked="checked" />
<input type="checkbox" checked="ChEcKeD" />

The following are invalid:

<input type="checkbox" checked="0" />
<input type="checkbox" checked="1" />
<input type="checkbox" checked="false" />
<input type="checkbox" checked="true" />

The absence of the attribute is the only valid syntax for false:

<input type="checkbox" />

Recommendation

If you care about writing valid XHTML, use checked="checked", since <input checked> is invalid and other alternatives are less readable. Else, just use <input checked> as it is shorter.

How to install JQ on Mac by command-line?

For most it is a breeze, however like you I had a difficult time installing jq

The best resources I found are: https://stedolan.github.io/jq/download/ and http://macappstore.org/jq/

However neither worked for me. I run python 2 & 3, and use brew in addition to pip, as well as Jupyter. I was only successful after brew uninstall jq then updating brew and rebooting my system

What worked for me was removing all previous installs then pip install jq

PowerShell The term is not recognized as cmdlet function script file or operable program

Yet another way this error message can occur...

If PowerShell is open in a directory other than the target file, e.g.:

If someScript.ps1 is located here: C:\SlowLearner\some_missing_path\someScript.ps1, then C:\SlowLearner>. ./someScript.ps1 wont work.

In that case, navigate to the path: cd some_missing_path then this would work:

C:\SlowLearner\some_missing_path>. ./someScript.ps1

Installing R on Mac - Warning messages: Setting LC_CTYPE failed, using "C"

On my Mac r is installed in /usr/local/bin/r, add line below in .bash_profile solved the same problem:

alias r="LANG=en_US.UTF-8 LC_ALL=en_US.UTF-8 r"

SQL WHERE.. IN clause multiple columns

Query:

select ord_num, agent_code, ord_date, ord_amount
from orders
where (agent_code, ord_amount) IN
(SELECT agent_code, MIN(ord_amount)
FROM orders 
GROUP BY agent_code);

above query worked for me in mysql. refer following link -->

https://www.w3resource.com/sql/subqueries/multiplee-row-column-subqueries.php

Simulate Keypress With jQuery

I believe this is what you're looking for:

var press = jQuery.Event("keypress");
press.ctrlKey = false;
press.which = 40;
$("whatever").trigger(press);

From here.

Convert datetime to Unix timestamp and convert it back in python

def datetime_to_epoch(d1):

    # create 1,1,1970 in same timezone as d1
    d2 = datetime(1970, 1, 1, tzinfo=d1.tzinfo)
    time_delta = d1 - d2
    ts = int(time_delta.total_seconds())
    return ts


def epoch_to_datetime_string(ts, tz_name="UTC"):
    x_timezone = timezone(tz_name)
    d1 = datetime.fromtimestamp(ts, x_timezone)
    x = d1.strftime("%d %B %Y %H:%M:%S")
    return x

Windows batch: echo without new line

Sample 1: This works and produces Exit code = 0. That is Good. Note the "." , directly after echo.

C:\Users\phife.dog\gitrepos\1\repo_abc\scripts #
@echo.| set /p JUNK_VAR=This is a message displayed like Linux echo -n would display it ... & echo %ERRORLEVEL%

This is a message displayed like Linux echo -n would display it ... 0

Sample 2: This works but produces Exit code = 1. That is Bad. Please note the lack of ".", after echo. That appears to be the difference.

C:\Users\phife.dog\gitrepos\1\repo_abc\scripts #
@echo | set /p JUNK_VAR=This is a message displayed like Linux echo -n would display it ... & echo %ERRORLEVEL%

This is a message displayed like Linux echo -n would display it ... 1

How to install an npm package from GitHub directly?

The general form of the syntax is

<protocol>://[<user>[:<password>]@]<hostname>[:<port>][:][/]<path>[#<commit-ish> | #semver:<semver>]

which means for your case it will be

npm install git+ssh://[email protected]/visionmedia/express.git

From npmjs docs:

npm install :

Installs the package from the hosted git provider, cloning it with git. For a full git remote url, only that URL will be attempted.

<protocol>://[<user>[:<password>]@]<hostname>[:<port>][:][/]<path>[#<commit-ish>

| #semver:] is one of git, git+ssh, git+http, git+https, or git+file.

If # is provided, it will be used to clone exactly that commit. If the commit-ish has the format #semver:, can be any valid semver range or exact version, and npm will look for any tags or refs matching that range in the remote repository, much as it would for a registry dependency. If neither # or

semver: is specified, then master is used.

If the repository makes use of submodules, those submodules will be cloned as well.

If the package being installed contains a prepare script, its dependencies and devDependencies will be installed, and the prepare script will be run, before the package is packaged and installed.

The following git environment variables are recognized by npm and will be added to the environment when running git:

  • GIT_ASKPASS
  • GIT_EXEC_PATH
  • GIT_PROXY_COMMAND
  • GIT_SSH
  • GIT_SSH_COMMAND
  • GIT_SSL_CAINFO GIT_SSL_NO_VERIFY

See the git man page for details.

Examples:

npm install git+ssh://[email protected]:npm/npm.git#v1.0.27
npm install git+ssh://[email protected]:npm/npm#semver:^5.0
npm install git+https://[email protected]/npm/npm.git
npm install git://github.com/npm/npm.git#v1.0.27
GIT_SSH_COMMAND='ssh -i ~/.ssh/custom_ident' npm install git+ssh://[email protected]:npm/npm.git npm install

What is the difference between exit and return?

the return statement exits from the current function and exit() exits from the program

they are the same when used in main() function

also return is a statement while exit() is a function which requires stdlb.h header file

mysqldump Error 1045 Access denied despite correct passwords etc

Don't enter the password with command. Just enter,

mysqldump -u <username> -p <db_name> > <backup_file>.sql

Then you will get a prompt to enter password.

Android - implementing startForeground for a service?

I'd start by completely filling in the Notification. Here is a sample project demonstrating the use of startForeground().

Change onclick action with a Javascript function

What might be easier, is to have two buttons and show/hide them in your functions. (ie. display:none|block;) Each button could then have it's own onclick with whatever code you need.

So, at first button1 would be display:block and button2 would be display:none. Then when you click button1 it would switch button2 to be display:block and button1 to be display:none.

Errors: Data path ".builders['app-shell']" should have required property 'class'

This setting works well under angular 8:

Package.json:

...
"dependencies": {
  "@angular/animations": "^8.2.14",
  "@angular/cdk": "8.2.3",
  "@angular/common": "^8.2.14",
  "@angular/compiler": "^8.2.14",
  "@angular/core": "^8.2.14",

...

"devDependencies": {
  "@angular-devkit/build-angular": "~0.803.29",
  "@angular/cli": "~8.3.29",
  "@angular/compiler-cli": "^8.2.14"

Certificate is trusted by PC but not by Android

I had a similar problem and wrote a detailed article about it. If anyone has the same problem, feel free to read my article.

https://developer-blog.net/administration/ssl-zertifikat-installieren/

It is a detailed problem description in German language.

What is the best way to remove a table row with jQuery?

Easy.. Try this

$("table td img.delete").click(function () {
    $(this).parent().parent().parent().fadeTo(400, 0, function () { 
        $(this).remove();
    });
    return false;
});

What is the "__v" field in Mongoose

From here:

The versionKey is a property set on each document when first created by Mongoose. This keys value contains the internal revision of the document. The name of this document property is configurable. The default is __v.

If this conflicts with your application you can configure as such:

new Schema({..}, { versionKey: '_somethingElse' })

Make REST API call in Swift

Api Call using Model Class

    let urlString = "http://--.154.--.78/------/index.php?route=api/coupon/all"

    let url = URL(string: urlString)
    var request = URLRequest(url: url!)
    request.httpMethod = "GET"

    URLSession.shared.dataTask(with:request) { (data, response, error) in
        if error != nil {
            print(error)
        } else {
            do {

                let parsedDictionaryArray = try JSONSerialization.jsonObject(with: data!) as! [String:AnyObject]
                print(parsedDictionaryArray)

                if let arry = parsedDictionaryArray["data"] as? [[String:AnyObject]] {
                for dic in arry {
                    let name = dic["name"]
                    let descriptionData = dic["description"]
                    self.modelReference.append(model(name: name as! String, descriptionStr: descriptionData as! String))
                    print(name!)
                }
                }
            } catch let error as NSError {
                print(error)
            }
        }

        }.resume()

create a variable and connect with model class

var modelReference = [model]()

create a model class New -> swift class

import Foundation
class model : NSObject{
var name : String
var descriptionStr: String

init(name : String, descriptionStr: String)
{
    self.name = name
    self.descriptionStr = descriptionStr
}

}

then we can connect with our table view objects

let cell = tableView.dequeueReusableCell(withIdentifier: "TableViewCellID")as! TableViewCell
    cell.listName.text = modelReference[indexPath.row].name

What is the !! (not not) operator in JavaScript?

_x000D_
_x000D_
const foo = 'bar';
console.log(!!foo); // Boolean: true
_x000D_
_x000D_
_x000D_

! negates (inverts) a value AND always returns/ produces a boolean. So !'bar' would yield false (because 'bar' is truthy => negated + boolean = false). With the additional ! operator, the value is negated again, so false becomes true.

How to compare two vectors for equality element by element in C++?

According to the discussion here you can directly compare two vectors using

==

if (vector1 == vector2){
   //true
}
else{
   //false
}

Must declare the scalar variable

This is most likely not an answer to the issue itself but this question pops up as first result when searching for Sql declare scalar variable hence i share a possible solution to this error.

In my case this error was caused by the use of ; after a SQL statement. Just remove it and the error will be gone.

I guess the cause is the same as @IronSean already posted in an comment above:

it's worth noting that using GO (or in this case ;) causes a new branch where declared variables aren't visible past the statement.

For example:

DECLARE @id int
SET @id = 78

SELECT * FROM MyTable WHERE Id = @var; <-- remove this character to avoid the error message
SELECT * FROM AnotherTable WHERE MyTableId = @var

Creating a class object in c++

Example example;

Here example is an object on the stack.

Example* example=new Example();

This could be broken into:

Example* example;
....
example=new Example();

Here the first statement creates a variable example which is a "pointer to Example". When the constructor is called, memory is allocated for it on the heap (dynamic allocation). It is the programmer's responsibility to free this memory when it is no longer needed. (C++ does not have garbage collection like java).

How to run a shell script at startup

Just have a line added to your crontab..

Make sure the file is executable:

chmod +x /path_to_you_file/your_file

To edit crontab file:

crontab -e

Line you have to add:

@reboot  /path_to_you_file/your_file

That simple!

How to convert index of a pandas dataframe into a column?

A very simple way of doing this is to use reset_index() method.For a data frame df use the code below:

df.reset_index(inplace=True)

This way, the index will become a column, and by using inplace as True,this become permanent change.

How to fill 100% of remaining height?

This can be done with tables:

<table cellpadding="0" cellspacing="0" width="100%" height="100%">
    <tr height="0%"><td>
        <div id="full">
            <!--contents of 1 -->
        </div>
    </td></tr>
    <tr><td>
        <div id="someid">
            <!--contents of 2 -->
        </div>
    </td></tr>
</table>

Then apply css to make someid fill the remaining space:

#someid {
    height: 100%;
}

Now, I can just hear the angry shouts from the crowd, "Oh noes, he's using tables! Feed him to the lions!" Please hear me out.

Unlike the accepted answer which accomplishes nothing aside from making the container div the full height of the page, this solution makes div #2 fill the remaining space as requested in the question. If you need that second div to fill the full height allotted to it, this is currently the only way to do it.

But feel free to prove me wrong, of course! CSS is always better.

PHP namespaces and "use"

The use operator is for giving aliases to names of classes, interfaces or other namespaces. Most use statements refer to a namespace or class that you'd like to shorten:

use My\Full\Namespace;

is equivalent to:

use My\Full\Namespace as Namespace;
// Namespace\Foo is now shorthand for My\Full\Namespace\Foo

If the use operator is used with a class or interface name, it has the following uses:

// after this, "new DifferentName();" would instantiate a My\Full\Classname
use My\Full\Classname as DifferentName;

// global class - making "new ArrayObject()" and "new \ArrayObject()" equivalent
use ArrayObject;

The use operator is not to be confused with autoloading. A class is autoloaded (negating the need for include) by registering an autoloader (e.g. with spl_autoload_register). You might want to read PSR-4 to see a suitable autoloader implementation.

Implementing autocomplete

I've built a fairly simple, reusable and functional Angular2 autocomplete component based on some of the ideas in this answer/other tutorials around on this subject and others. It's by no means comprehensive but may be helpful if you decide to build your own.

The component:

import { Component, Input, Output, OnInit, ContentChild, EventEmitter, HostListener } from '@angular/core';
import { Observable } from "rxjs/Observable";
import { AutoCompleteRefDirective } from "./autocomplete.directive";

@Component({
    selector: 'autocomplete',
    template: `
<ng-content></ng-content>
<div class="autocomplete-wrapper" (click)="clickedInside($event)">
    <div class="list-group autocomplete" *ngIf="results">
        <a [routerLink]="" class="list-group-item" (click)="selectResult(result)" *ngFor="let result of results; let i = index" [innerHTML]="dataMapping(result) | highlight: query" [ngClass]="{'active': i == selectedIndex}"></a>
    </div>
</div>
    `,
    styleUrls: ['./autocomplete.component.css']
})
export class AutoCompleteComponent implements OnInit {

    @ContentChild(AutoCompleteRefDirective)
    public input: AutoCompleteRefDirective;

    @Input() data: (searchTerm: string) => Observable<any[]>;
    @Input() dataMapping: (obj: any) => string;
    @Output() onChange = new EventEmitter<any>();

    @HostListener('document:click', ['$event'])
    clickedOutside($event: any): void {
        this.clearResults();
    }

    public results: any[];
    public query: string;
    public selectedIndex: number = 0;
    private searchCounter: number = 0;

    ngOnInit(): void {
        this.input.change
            .subscribe((query: string) => {
                this.query = query;
                this.onChange.emit();
                this.searchCounter++;
                let counter = this.searchCounter;

                if (query) {
                    this.data(query)
                        .subscribe(data => {
                            if (counter == this.searchCounter) {
                                this.results = data;
                                this.input.hasResults = data.length > 0;
                                this.selectedIndex = 0;
                            }
                        });
                }
                else this.clearResults();
            });

        this.input.cancel
            .subscribe(() => {
                this.clearResults();
            });

        this.input.select
            .subscribe(() => {
                if (this.results && this.results.length > 0)
                {
                    this.selectResult(this.results[this.selectedIndex]);
                }
            });

        this.input.up
            .subscribe(() => {
                if (this.results && this.selectedIndex > 0) this.selectedIndex--;
            });

        this.input.down
            .subscribe(() => {
                if (this.results && this.selectedIndex + 1 < this.results.length) this.selectedIndex++;
            });
    }

    selectResult(result: any): void {
        this.onChange.emit(result);
        this.clearResults();
    }

    clickedInside($event: any): void {
        $event.preventDefault();
        $event.stopPropagation();
    }

    private clearResults(): void {
        this.results = [];
        this.selectedIndex = 0;
        this.searchCounter = 0;
        this.input.hasResults = false;
    }
}

The component CSS:

.autocomplete-wrapper {
    position: relative;
}

.autocomplete {
    position: absolute;
    z-index: 100;
    width: 100%;
}

The directive:

import { Directive, Input, Output, HostListener, EventEmitter } from '@angular/core';

@Directive({
    selector: '[autocompleteRef]'
})
export class AutoCompleteRefDirective {
    @Input() hasResults: boolean = false;
    @Output() change = new EventEmitter<string>();
    @Output() cancel = new EventEmitter();
    @Output() select = new EventEmitter();
    @Output() up = new EventEmitter();
    @Output() down = new EventEmitter();

    @HostListener('input', ['$event'])
    oninput(event: any) {
        this.change.emit(event.target.value);
    }

    @HostListener('keydown', ['$event'])
    onkeydown(event: any)
    {
        switch (event.keyCode) {
            case 27:
                this.cancel.emit();
                return false;
            case 13:
                var hasResults = this.hasResults;
                this.select.emit();
                return !hasResults;
            case 38:
                this.up.emit();
                return false;
            case 40:
                this.down.emit();
                return false;
            default:
        }
    }
}

The highlight pipe:

import { Pipe, PipeTransform } from '@angular/core';

@Pipe({
    name: 'highlight'
})

export class HighlightPipe implements PipeTransform {
    transform(value: string, args: any): any {
        var re = new RegExp(args, 'gi');

        return value.replace(re, function (match) {
            return "<strong>" + match + "</strong>";
        })

    }
}

The implementation:

import { Component } from '@angular/core';
import { Observable } from "rxjs/Observable";
import { Subscriber } from "rxjs/Subscriber";

@Component({
    selector: 'home',
    template: `
<autocomplete [data]="getData" [dataMapping]="dataMapping" (onChange)="change($event)">
    <input type="text" class="form-control" name="AutoComplete" placeholder="Search..." autocomplete="off" autocompleteRef />
</autocomplete>
    `
})
export class HomeComponent {

    getData = (query: string) => this.search(query);

    // The dataMapping property controls the mapping of an object returned via getData.
    // to a string that can be displayed to the use as an option to select.
    dataMapping = (obj: any) => obj;

    // This function is called any time a change is made in the autocomplete.
    // When the text is changed manually, no object is passed.
    // When a selection is made the object is passed.
    change(obj: any): void {
        if (obj) {
            // You can do pretty much anything here as the entire object is passed if it's been selected.
            // Navigate to another page, update a model etc.
            alert(obj);
        }
    }

    private searchData = ['one', 'two', 'three', 'four', 'five', 'six', 'seven', 'eight', 'nine', 'ten'];

    // This function mimics an Observable http service call.
    // In reality it's probably calling your API, but today it's looking at mock static data.
    private search(query: string): Observable<any>
    {
        return new Observable<any>((subscriber: Subscriber<any>) => subscriber
            .next())
            .map(o => this.searchData.filter(d => d.indexOf(query) > -1));
    }
}

how to redirect to home page

maybe

var re = /^https?:\/\/[^/]+/i;
window.location.href = re.exec(window.location.href)[0];

is what you're looking for?

How can I express that two values are not equal to eachother?

if (!secondaryPassword.equals(initialPassword)) 

Stop fixed position at footer

I went with a modification of @user1097431 's answer:

function menuPosition(){
// distance from top of footer to top of document
var footertotop = ($('.footer').position().top);
// distance user has scrolled from top, adjusted to take in height of bar (42 pixels inc. padding)
var scrolltop = $(document).scrollTop() + window.innerHeight;
// difference between the two
var difference = scrolltop-footertotop;

// if user has scrolled further than footer,
// pull sidebar up using a negative margin
if (scrolltop > footertotop) {
    $('#categories-wrapper').css({
       'bottom' : difference
   });
}else{
    $('#categories-wrapper').css({
       'bottom' : 0
   });
 };
};

Logging levels - Logback - rule-of-thumb to assign log levels

This may also tangentially help, to understand if a logging request (from the code) at a certain level will result in it actually being logged given the effective logging level that a deployment is configured with. Decide what effective level you want to configure you deployment with from the other Answers here, and then refer to this to see if a particular logging request from your code will actually be logged then...

For examples:

  • "Will a logging code line that logs at WARN actually get logged on my deployment configured with ERROR?" The table says, NO.
  • "Will a logging code line that logs at WARN actually get logged on my deployment configured with DEBUG?" The table says, YES.

from logback documentation:

In a more graphic way, here is how the selection rule works. In the following table, the vertical header shows the level of the logging request, designated by p, while the horizontal header shows effective level of the logger, designated by q. The intersection of the rows (level request) and columns (effective level) is the boolean resulting from the basic selection rule. enter image description here

So a code line that requests logging will only actually get logged if the effective logging level of its deployment is less than or equal to that code line's requested level of severity.

Passing a local variable from one function to another

You can very easily use this to re-use the value of the variable in another function.

// Use this in source window.var1= oEvent.getSource().getBindingContext();

// Get value of var1 in destination var var2= window.var1;

How to work with complex numbers in C?

To extract the real part of a complex-valued expression z, use the notation as __real__ z. Similarly, use __imag__ attribute on the z to extract the imaginary part.

For example;

__complex__ float z;
float r;
float i;
r = __real__ z;
i = __imag__ z;

r is the real part of the complex number "z" i is the imaginary part of the complex number "z"

Java parsing XML document gives "Content not allowed in prolog." error

You are not providing the correct address for the file. You need to provide an address such as C:/Users/xyz/Desktop/myfile.xml

OpenCV error: the function is not implemented

I hope this answer is still useful, despite problem seems to be quite old.

If you have Anaconda installed, and your OpenCV does not support GTK+ (as in this case), you can simply type

conda install -c menpo opencv=2.4.11

It will install suitable OpenCV version that does not produce a mentioned error. Besides, it will reinstall previously installed OpenCV if there was one as a part of Anaconda.

Good examples of python-memcache (memcached) being used in Python?

It's fairly simple. You write values using keys and expiry times. You get values using keys. You can expire keys from the system.

Most clients follow the same rules. You can read the generic instructions and best practices on the memcached homepage.

If you really want to dig into it, I'd look at the source. Here's the header comment:

"""
client module for memcached (memory cache daemon)

Overview
========

See U{the MemCached homepage<http://www.danga.com/memcached>} for more about memcached.

Usage summary
=============

This should give you a feel for how this module operates::

    import memcache
    mc = memcache.Client(['127.0.0.1:11211'], debug=0)

    mc.set("some_key", "Some value")
    value = mc.get("some_key")

    mc.set("another_key", 3)
    mc.delete("another_key")

    mc.set("key", "1")   # note that the key used for incr/decr must be a string.
    mc.incr("key")
    mc.decr("key")

The standard way to use memcache with a database is like this::

    key = derive_key(obj)
    obj = mc.get(key)
    if not obj:
        obj = backend_api.get(...)
        mc.set(key, obj)

    # we now have obj, and future passes through this code
    # will use the object from the cache.

Detailed Documentation
======================

More detailed documentation is available in the L{Client} class.
"""

input checkbox true or checked or yes

Only checked and checked="checked" are valid. Your other options depend on error recovery in browsers.

checked="yes" and checked="true" are particularly bad as they imply that checked="no" and checked="false" will set the default state to be unchecked … which they will not.

Text overwrite in visual studio 2010

Visual Studio : Right Bottom : Look for OVR label. Double Click on it.

Bingo...

"Cannot GET /" with Connect on Node.js

The solution to "Cannot Get /" can usually be determined if you do an "ng build" in the command line. You will find most often that one of your "imports" does not have the correct path.

CSS fill remaining width

You can realize this layout using CSS table-cells.

Modify your HTML slightly as follows:

<div id="header">
    <div class="container">
        <div class="logoBar">
            <img src="http://placehold.it/50x40" />
        </div>
        <div id="searchBar">
            <input type="text" />
        </div>
        <div class="button orange" id="myAccount">My Account</div>
        <div class="button red" id="basket">Basket (2)</div>
    </div>
</div>

Just remove the wrapper element around the two .button elements.

Apply the following CSS:

#header {
    background-color: #323C3E;
    width:100%;
}
.container {
    display: table;
    width: 100%;
}
.logoBar, #searchBar, .button {
    display: table-cell;
    vertical-align: middle;
    width: auto;
}
.logoBar img {
    display: block;
}
#searchBar {
    background-color: #FFF2BC;
    width: 90%;
    padding: 0 50px 0 10px;
}

#searchBar input {
    width: 100%;
}

.button {
    white-space: nowrap;
    padding:22px;
}

Apply display: table to .container and give it 100% width.

For .logoBar, #searchBar, .button, apply display: table-cell.

For the #searchBar, set the width to 90%, which force all the other elements to compute a shrink-to-fit width and the search bar will expand to fill in the rest of the space.

Use text-align and vertical-align in the table cells as needed.

See demo at: http://jsfiddle.net/audetwebdesign/zWXQt/

How to check if std::map contains a key without doing insert?

Use my_map.count( key ); it can only return 0 or 1, which is essentially the Boolean result you want.

Alternately my_map.find( key ) != my_map.end() works too.

How to clear a data grid view

You could take this next instruction and would do the work with lack of perfomance. If you want to see the effect of that, put one of the 2 next instructions (Technically similars) where you need to clear the DataGridView into a try{} catch(...){} finally block and wait what occurs.

     while (dataGridView1.Rows.Count > 1)
    {
        dataGridView1.Rows.RemoveAt(0);
    }

    foreach (object _Cols in dataGridView1.Columns)
    {
        dataGridView1.Columns.RemoveAt(0);
    }

You improve this task but its not enough, there is a problem to reset a DataGridView, because of the colums that remains in the DataGridView object. Finally I suggest, the best way i've implemented in my home practice is to handle this gridView as a file with rows, columns: a record collection based on the match between rows and columns. If you can improve, then take your own choice a) or b): foreach or while.

     //(a): With foreach 
    foreach (object _Cols in dataGridView1.Columns)
    {
        dataGridView1.Columns.RemoveAt(0);
    }

    foreach(object _row in dataGridView1.Rows){
        dataGridView1.Rows.RemoveAt(0);
    }

    //(b): With foreach 
    while (dataGridView1.Rows.Count > 1)
    {
        dataGridView1.Rows.RemoveAt(0);
    }
    while (dataGridView1.Columns.Count > 0)
    {
        dataGridView1.Columns.RemoveAt(0);
    }

Well, as a recomendation Never in your life delete the columns first, the order is before the rows after the cols, because logically the columns where created first and then the rows.It would be a penalty in terms of correct analisys.

     foreach (object _Cols in dataGridView1.Columns)
    {
        dataGridView1.Columns.RemoveAt(0);
    }
    foreach (object _row in dataGridView1.Rows)
    {
        dataGridView1.Rows.RemoveAt(0);
    }
    while (dataGridView1.Rows.Count > 1)
    {
        dataGridView1.Rows.RemoveAt(0);
    }

    while (dataGridView1.Columns.Count > 0)
    {
        dataGridView1.Columns.RemoveAt(0);
    }

Then, Put it inside a function or method.

 private void ClearDataGridViewLoopWhile()
{           
    while (dataGridView1.Rows.Count > 1)
    {
        dataGridView1.Rows.RemoveAt(0);
    }

    while (dataGridView1.Columns.Count > 0)
    {
        dataGridView1.Columns.RemoveAt(0);
    }
}

private void ClearDataGridViewForEach()
{
    foreach (object _Cols in dataGridView1.Columns)
    {
        dataGridView1.Columns.RemoveAt(0);
    }
    foreach (object _row in dataGridView1.Rows)
    {
        dataGridView1.Rows.RemoveAt(0);
    }
}

Finally, call your new function ClearDataGridViewLoopWhile(); or ClearDataGridViewForEach(); where you need to use it, but its recomended when you are making queries and changing over severall tables that will load with diferents header names in the grieView. But if you want preserve headers here there is a solution given.

C# How can I check if a URL exists/is valid?

I have always found Exceptions are much slower to be handled.

Perhaps a less intensive way would yeild a better, faster, result?

public bool IsValidUri(Uri uri)
{

    using (HttpClient Client = new HttpClient())
    {

    HttpResponseMessage result = Client.GetAsync(uri).Result;
    HttpStatusCode StatusCode = result.StatusCode;

    switch (StatusCode)
    {

        case HttpStatusCode.Accepted:
            return true;
        case HttpStatusCode.OK:
            return true;
         default:
            return false;
        }
    }
}

Then just use:

IsValidUri(new Uri("http://www.google.com/censorship_algorithm"));

What is javax.inject.Named annotation supposed to be used for?

Regarding #2, according to the JSR-330 spec:

This package provides dependency injection annotations that enable portable classes, but it leaves external dependency configuration up to the injector implementation.

So it's up to the provider to determine which objects are available for injection. In the case of Spring it is all Spring beans. And any class annotated with JSR-330 annotations are automatically added as Spring beans when using an AnnotationConfigApplicationContext.

How do I return multiple values from a function in C?

Two different approaches:

  1. Pass in your return values by pointer, and modify them inside the function. You declare your function as void, but it's returning via the values passed in as pointers.
  2. Define a struct that aggregates your return values.

I think that #1 is a little more obvious about what's going on, although it can get tedious if you have too many return values. In that case, option #2 works fairly well, although there's some mental overhead involved in making specialized structs for this purpose.

JavaScript: Upload file

Unless you're trying to upload the file using ajax, just submit the form to /upload/image.

<form enctype="multipart/form-data" action="/upload/image" method="post">
    <input id="image-file" type="file" />
</form>

If you do want to upload the image in the background (e.g. without submitting the whole form), you can use ajax:

ReferenceError: $ is not defined

Use Google CDN for fast loading:

<script type="text/javascript" src="//ajax.googleapis.com/ajax/libs/jquery/2.0.0/jquery.min.js"></script>

Logical Operators, || or OR?

The difference between respectively || and OR and && and AND is operator precedence :

$bool = FALSE || TRUE;

  • interpreted as ($bool = (FALSE || TRUE))
  • value of $bool is TRUE

$bool = FALSE OR TRUE;

  • interpreted as (($bool = FALSE) OR TRUE)
  • value of $bool is FALSE

$bool = TRUE && FALSE;

  • interpreted as ($bool = (TRUE && FALSE))
  • value of $bool is FALSE

$bool = TRUE AND FALSE;

  • interpreted as (($bool = TRUE) AND FALSE)
  • value of $bool is TRUE

How to create a popup windows in javafx

Take a look at jfxmessagebox (http://en.sourceforge.jp/projects/jfxmessagebox/) if you are looking for very simple dialog popups.

Windows path in Python

In case you'd like to paste windows path from other source (say, File Explorer) - you can do so via input() call in python console:

>>> input()
D:\EP\stuff\1111\this_is_a_long_path\you_dont_want\to_type\or_edit_by_hand
'D:\\EP\\stuff\\1111\\this_is_a_long_path\\you_dont_want\\to_type\\or_edit_by_hand'

Then just copy the result

Serializing an object to JSON

Download https://github.com/douglascrockford/JSON-js/blob/master/json2.js, include it and do

var json_data = JSON.stringify(obj);

IF/ELSE Stored Procedure

It isn't giving any errors? Try
SET @tmpType = 'premium'
and
SET @tmpType = 'basic'

angularjs to output plain text instead of html

Use ng-bind-html this is only proper and simplest way

Log exception with traceback

You can log all uncaught exceptions on the main thread by assigning a handler to sys.excepthook, perhaps using the exc_info parameter of Python's logging functions:

import sys
import logging

logging.basicConfig(filename='/tmp/foobar.log')

def exception_hook(exc_type, exc_value, exc_traceback):
    logging.error(
        "Uncaught exception",
        exc_info=(exc_type, exc_value, exc_traceback)
    )

sys.excepthook = exception_hook

raise Exception('Boom')

If your program uses threads, however, then note that threads created using threading.Thread will not trigger sys.excepthook when an uncaught exception occurs inside them, as noted in Issue 1230540 on Python's issue tracker. Some hacks have been suggested there to work around this limitation, like monkey-patching Thread.__init__ to overwrite self.run with an alternative run method that wraps the original in a try block and calls sys.excepthook from inside the except block. Alternatively, you could just manually wrap the entry point for each of your threads in try/except yourself.

jQuery attr() change img src

You remove the original image here:

newImg.animate(css, SPEED, function() {
    img.remove();
    newImg.removeClass('morpher');
    (callback || function() {})();
});

And all that's left behind is newImg. Then you reset link references the image using #rocket:

$("#rocket").attr('src', ...

But your newImg doesn't have an id attribute let alone an id of rocket.

To fix this, you need to remove img and then set the id attribute of newImg to rocket:

newImg.animate(css, SPEED, function() {
    var old_id = img.attr('id');
    img.remove();
    newImg.attr('id', old_id);
    newImg.removeClass('morpher');
    (callback || function() {})();
});

And then you'll get the shiny black rocket back again: http://jsfiddle.net/ambiguous/W2K9D/

UPDATE: A better approach (as noted by mellamokb) would be to hide the original image and then show it again when you hit the reset button. First, change the reset action to something like this:

$("#resetlink").click(function(){
    clearInterval(timerRocket);
    $("#wrapper").css('top', '250px');
    $('.throbber, .morpher').remove(); // Clear out the new stuff.
    $("#rocket").show();               // Bring the original back.
});

And in the newImg.load function, grab the images original size:

var orig = {
    width: img.width(),
    height: img.height()
};

And finally, the callback for finishing the morphing animation becomes this:

newImg.animate(css, SPEED, function() {
    img.css(orig).hide();
    (callback || function() {})();
});

New and improved: http://jsfiddle.net/ambiguous/W2K9D/1/

The leaking of $('.throbber, .morpher') outside the plugin isn't the best thing ever but it isn't a big deal as long as it is documented.

How to remove multiple deleted files in Git repository

When I have a lot of files I've deleted that are unstaged for commit, you can git rm them all in one show with:

for i in `git status | grep deleted | awk '{print $3}'`; do git rm $i; done

As question answerer mentioned, be careful with git rm.

Difference between rake db:migrate db:reset and db:schema:load

As far as I understand, it is going to drop your database and re-create it based on your db/schema.rb file. That is why you need to make sure that your schema.rb file is always up to date and under version control.

html select option separator

If you don't want to use the optgroup element, put the dashes in an option element instead and give it the disabled attribute. It will be visible, but greyed out.

<option disabled>----------</option>

What is Robocopy's "restartable" option?

Restartable mode (/Z) has to do with a partially-copied file. With this option, should the copy be interrupted while any particular file is partially copied, the next execution of robocopy can pick up where it left off rather than re-copying the entire file.

That option could be useful when copying very large files over a potentially unstable connection.

Backup mode (/B) has to do with how robocopy reads files from the source system. It allows the copying of files on which you might otherwise get an access denied error on either the file itself or while trying to copy the file's attributes/permissions. You do need to be running in an Administrator context or otherwise have backup rights to use this flag.

Find Nth occurrence of a character in a string

Hi all i have created two overload methods for finding nth occurrence of char and for text with less complexity without navigating through loop ,which increase performance of your application.

public static int NthIndexOf(string text, char searchChar, int nthindex)
{
   int index = -1;
   try
   {
      var takeCount = text.TakeWhile(x => (nthindex -= (x == searchChar ? 1 : 0)) > 0).Count();
      if (takeCount < text.Length) index = takeCount;
   }
   catch { }
   return index;
}
public static int NthIndexOf(string text, string searchText, int nthindex)
{
     int index = -1;
     try
     {
        Match m = Regex.Match(text, "((" + searchText + ").*?){" + nthindex + "}");
        if (m.Success) index = m.Groups[2].Captures[nthindex - 1].Index;
     }
     catch { }
     return index;
}

Best way to convert strings to symbols in hash

a shorter one-liner fwiw:

my_hash.inject({}){|h,(k,v)| h.merge({ k.to_sym => v}) }

How to implement the factory method pattern in C++ correctly

First of all, there are cases when object construction is a task complex enough to justify its extraction to another class.

I believe this point is incorrect. The complexity doesn't really matter. The relevance is what does. If an object can be constructed in one step (not like in the builder pattern), the constructor is the right place to do it. If you really need another class to perform the job, then it should be a helper class that is used from the constructor anyway.

Vec2(float x, float y);
Vec2(float angle, float magnitude); // not a valid overload!

There is an easy workaround for this:

struct Cartesian {
  inline Cartesian(float x, float y): x(x), y(y) {}
  float x, y;
};
struct Polar {
  inline Polar(float angle, float magnitude): angle(angle), magnitude(magnitude) {}
  float angle, magnitude;
};
Vec2(const Cartesian &cartesian);
Vec2(const Polar &polar);

The only disadvantage is that it looks a bit verbose:

Vec2 v2(Vec2::Cartesian(3.0f, 4.0f));

But the good thing is that you can immediately see what coordinate type you're using, and at the same time you don't have to worry about copying. If you want copying, and it's expensive (as proven by profiling, of course), you may wish to use something like Qt's shared classes to avoid copying overhead.

As for the allocation type, the main reason to use the factory pattern is usually polymorphism. Constructors can't be virtual, and even if they could, it wouldn't make much sense. When using static or stack allocation, you can't create objects in a polymorphic way because the compiler needs to know the exact size. So it works only with pointers and references. And returning a reference from a factory doesn't work too, because while an object technically can be deleted by reference, it could be rather confusing and bug-prone, see Is the practice of returning a C++ reference variable, evil? for example. So pointers are the only thing that's left, and that includes smart pointers too. In other words, factories are most useful when used with dynamic allocation, so you can do things like this:

class Abstract {
  public:
    virtual void do() = 0;
};

class Factory {
  public:
    Abstract *create();
};

Factory f;
Abstract *a = f.create();
a->do();

In other cases, factories just help to solve minor problems like those with overloads you have mentioned. It would be nice if it was possible to use them in a uniform way, but it doesn't hurt much that it is probably impossible.

How to rename array keys in PHP?

Recursive php rename keys function:

function replaceKeys($oldKey, $newKey, array $input){
    $return = array(); 
    foreach ($input as $key => $value) {
        if ($key===$oldKey)
            $key = $newKey;

        if (is_array($value))
            $value = replaceKeys( $oldKey, $newKey, $value);

        $return[$key] = $value;
    }
    return $return; 
}

Is there any difference between "!=" and "<>" in Oracle Sql?

Actually, there are four forms of this operator:

<>
!=
^=

and even

¬= -- worked on some obscure platforms in the dark ages

which are the same, but treated differently when a verbatim match is required (stored outlines or cached queries).

Get first key in a (possibly) associative array?

You can play with your array

$daysArray = array('Monday', 'Tuesday', 'Sunday');
$day = current($transport); // $day = 'Monday';
$day = next($transport);    // $day = 'Tuesday';
$day = current($transport); // $day = 'Tuesday';
$day = prev($transport);    // $day = 'Monday';
$day = end($transport);     // $day = 'Sunday';
$day = current($transport); // $day = 'Sunday';

To get the first element of array you can use current and for last element you can use end

Edit

Just for the sake for not getting any more down votes for the answer you can convert you key to value using array_keys and use as shown above.

java.util.MissingResourceException: Can't find bundle for base name 'property_file name', locale en_US

You should set property file name without .properties extension, it works correctly for me:)

How to convert CSV file to multiline JSON?

I see this is old but I needed the code from SingleNegationElimination however I had issue with the data containing non utf-8 characters. These appeared in fields I was not overly concerned with so I chose to ignore them. However that took some effort. I am new to python so with some trial and error I got it to work. The code is a copy of SingleNegationElimination with the extra handling of utf-8. I tried to do it with https://docs.python.org/2.7/library/csv.html but in the end gave up. The below code worked.

import csv, json

csvfile = open('file.csv', 'r')
jsonfile = open('file.json', 'w')

fieldnames = ("Scope","Comment","OOS Code","In RMF","Code","Status","Name","Sub Code","CAT","LOB","Description","Owner","Manager","Platform Owner")
reader = csv.DictReader(csvfile , fieldnames)

code = ''
for row in reader:
    try:
        print('+' + row['Code'])
        for key in row:
            row[key] = row[key].decode('utf-8', 'ignore').encode('utf-8')      
        json.dump(row, jsonfile)
        jsonfile.write('\n')
    except:
        print('-' + row['Code'])
        raise

Comparing two branches in Git?

git diff branch_1..branch_2

That will produce the diff between the tips of the two branches. If you'd prefer to find the diff from their common ancestor to test, you can use three dots instead of two:

git diff branch_1...branch_2

How do I create a MessageBox in C#?

MessageBox.Show also returns a DialogResult, which if you put some buttons on there, means you can have it returned what the user clicked. Most of the time I write something like

if (MessageBox.Show("Do you want to continue?", "Question", MessageBoxButtons.YesNo) == MessageBoxResult.Yes) {
     //some interesting behaviour here
}

which I guess is a bit unwieldy but it gets the job done.

See https://docs.microsoft.com/en-us/dotnet/api/system.windows.forms.dialogresult for additional enum options you can use here.

How to modify a CSS display property from JavaScript?

I found the solution.

As said in the EDIT of my answer, a <div> is misfunctioning in a <table>. So I wrote this code instead :

<tr id="hidden" style="display:none;">
    <td class="depot_table_left">
        <label for="sexe">Sexe</label>
    </td>
    <td>
        <select type="text" name="sexe">
            <option value="1">Sexe</option>
            <option value="2">Joueur</option>
            <option value="3">Joueuse</option>
        </select>
    </td>
</tr>

And this is working fine.

Thanks everybody ;)

Multiple contexts with the same path error running web service in Eclipse using Tomcat

In my case I found duplicate paths in Servers/Tomcat5.5 at localhost-config/server.xml under tag. Removing the duplicates solved the problem.

Should a function have only one return statement?

Structured programming says you should only ever have one return statement per function. This is to limit the complexity. Many people such as Martin Fowler argue that it is simpler to write functions with multiple return statements. He presents this argument in the classic refactoring book he wrote. This works well if you follow his other advice and write small functions. I agree with this point of view and only strict structured programming purists adhere to single return statements per function.

Using grep to search for hex strings in a file

We tried several things before arriving at an acceptable solution:

xxd -u /usr/bin/xxd | grep 'DF'
00017b0: 4010 8D05 0DFF FF0A 0300 53E3 0610 A003  @.........S.....


root# grep -ibH "df" /usr/bin/xxd
Binary file /usr/bin/xxd matches
xxd -u /usr/bin/xxd | grep -H 'DF'
(standard input):00017b0: 4010 8D05 0DFF FF0A 0300 53E3 0610 A003  @.........S.....

Then found we could get usable results with

xxd -u /usr/bin/xxd > /tmp/xxd.hex ; grep -H 'DF' /tmp/xxd

Note that using a simple search target like 'DF' will incorrectly match characters that span across byte boundaries, i.e.

xxd -u /usr/bin/xxd | grep 'DF'
00017b0: 4010 8D05 0DFF FF0A 0300 53E3 0610 A003  @.........S.....
--------------------^^

So we use an ORed regexp to search for ' DF' OR 'DF ' (the searchTarget preceded or followed by a space char).

The final result seems to be

xxd -u -ps -c 10000000000 DumpFile > DumpFile.hex
egrep ' DF|DF ' Dumpfile.hex

0001020: 0089 0424 8D95 D8F5 FFFF 89F0 E8DF F6FF  ...$............
-----------------------------------------^^
0001220: 0C24 E871 0B00 0083 F8FF 89C3 0F84 DF03  .$.q............
--------------------------------------------^^

do <something> N times (declarative syntax)

Array.from (ES6)

function doSomthing() {
    ...
}

Use it like so:

Array.from(Array(length).keys()).forEach(doSomthing);

Or

Array.from({ length }, (v, i) => i).forEach(doSomthing);

Or

// array start counting from 1
Array.from({ length }, (v, i) => ++i).forEach(doSomthing);

JQuery Number Formatting

If you need to handle multiple currencies, various number formats etc. I can recommend autoNumeric. Works a treat. Have been using it successfully for several years now.

need to add a class to an element

Try using setAttribute on the result:

result.setAttribute("class","red"); 

Can't bind to 'dataSource' since it isn't a known property of 'table'

if your "import { MatTableModule } from '@angular/material';" is on a shared module, make sure you export it.

sharedmodule.ts:

import { MatTableModule } from '@angular/material' 

@NgModule({
  imports: [
    // ...
    MatTableModule
    // ...
  ],
  exports:[ MatTableModule ]
})

then on your custom module where you define the component that use material table:

custommodule.ts:

@NgModule({
imports: [ sharedmodule ]     
})

SQL Server Insert if not exists

instead of below Code

BEGIN
   INSERT INTO EmailsRecebidos (De, Assunto, Data)
   VALUES (@_DE, @_ASSUNTO, @_DATA)
   WHERE NOT EXISTS ( SELECT * FROM EmailsRecebidos 
                   WHERE De = @_DE
                   AND Assunto = @_ASSUNTO
                   AND Data = @_DATA);
END

replace with

BEGIN
   IF NOT EXISTS (SELECT * FROM EmailsRecebidos 
                   WHERE De = @_DE
                   AND Assunto = @_ASSUNTO
                   AND Data = @_DATA)
   BEGIN
       INSERT INTO EmailsRecebidos (De, Assunto, Data)
       VALUES (@_DE, @_ASSUNTO, @_DATA)
   END
END

Updated : (thanks to @Marc Durdin for pointing)

Note that under high load, this will still sometimes fail, because a second connection can pass the IF NOT EXISTS test before the first connection executes the INSERT, i.e. a race condition. See stackoverflow.com/a/3791506/1836776 for a good answer on why even wrapping in a transaction doesn't solve this.

How to detect the swipe left or Right in Android?

public class TransferMarket extends Activity {

    float x1,x2;
    float y1, y2;

    @Override
    protected void onCreate(Bundle savedInstanceState)
    {
        super.onCreate(savedInstanceState);
        setContentView(R.layout.activity_transfer_market);
    }

    // onTouchEvent () method gets called when User performs any touch event on screen

    // Method to handle touch event like left to right swap and right to left swap

    public boolean onTouchEvent(MotionEvent touchevent)
    {
        switch (touchevent.getAction())
        {
            // when user first touches the screen we get x and y coordinate
            case MotionEvent.ACTION_DOWN:
            {
                x1 = touchevent.getX();
                y1 = touchevent.getY();
                break;
            }
            case MotionEvent.ACTION_UP:
            {
                x2 = touchevent.getX();
                y2 = touchevent.getY();

                //if left to right sweep event on screen
                if (x1 < x2)
                {
                    Toast.makeText(this, "Left to Right Swap Performed", Toast.LENGTH_LONG).show();
                }

                // if right to left sweep event on screen
                if (x1 > x2)
                {
                    Toast.makeText(this, "Right to Left Swap Performed", Toast.LENGTH_LONG).show();
                }

                // if UP to Down sweep event on screen
                if (y1 < y2)
                {
                    Toast.makeText(this, "UP to Down Swap Performed", Toast.LENGTH_LONG).show();
                }

                //if Down to UP sweep event on screen
                if (y1 > y2)
                {
                    Toast.makeText(this, "Down to UP Swap Performed", Toast.LENGTH_LONG).show();
                }
                break;
            }
        }
        return false;
    }

Sorting arraylist in alphabetical order (case insensitive)

Custom Comparator should help

Collections.sort(list, new Comparator<String>() {
    @Override
    public int compare(String s1, String s2) {
        return s1.compareToIgnoreCase(s2);
    }
});

Or if you are using Java 8:

list.sort(String::compareToIgnoreCase);

Does C# have extension properties?

As @Psyonity mentioned, you can use the conditionalWeakTable to add properties to existing objects. Combined with the dynamic ExpandoObject, you could implement dynamic extension properties in a few lines:

using System.Dynamic;
using System.Runtime.CompilerServices;

namespace ExtensionProperties
{
    /// <summary>
    /// Dynamically associates properies to a random object instance
    /// </summary>
    /// <example>
    /// var jan = new Person("Jan");
    ///
    /// jan.Age = 24; // regular property of the person object;
    /// jan.DynamicProperties().NumberOfDrinkingBuddies = 27; // not originally scoped to the person object;
    ///
    /// if (jan.Age &lt; jan.DynamicProperties().NumberOfDrinkingBuddies)
    /// Console.WriteLine("Jan drinks too much");
    /// </example>
    /// <remarks>
    /// If you get 'Microsoft.CSharp.RuntimeBinder.CSharpArgumentInfo.Create' you should reference Microsoft.CSharp
    /// </remarks>
    public static class ObjectExtensions
    {
        ///<summary>Stores extended data for objects</summary>
        private static ConditionalWeakTable<object, object> extendedData = new ConditionalWeakTable<object, object>();

        /// <summary>
        /// Gets a dynamic collection of properties associated with an object instance,
        /// with a lifetime scoped to the lifetime of the object
        /// </summary>
        /// <param name="obj">The object the properties are associated with</param>
        /// <returns>A dynamic collection of properties associated with an object instance.</returns>
        public static dynamic DynamicProperties(this object obj) => extendedData.GetValue(obj, _ => new ExpandoObject());
    }
}

A usage example is in the xml comments:

var jan = new Person("Jan");

jan.Age = 24; // regular property of the person object;
jan.DynamicProperties().NumberOfDrinkingBuddies = 27; // not originally scoped to the person object;

if (jan.Age < jan.DynamicProperties().NumberOfDrinkingBuddies)
{
    Console.WriteLine("Jan drinks too much");
}

jan = null; // NumberOfDrinkingBuddies will also be erased during garbage collection

Can Android do peer-to-peer ad-hoc networking?

In addition to Telmo Marques answer: I use Virtual Router for this.

Like connectify it creates an accesspoint on your Windows 8, Windows 7 or 2008 R2 machine, but it's open-source.

Pull is not possible because you have unmerged files, git stash doesn't work. Don't want to commit

I've tried both these and still get failure due to conflicts. At the end of my patience, I cloned master in another location, copied everything into the other branch and committed it. which let me continue. The "-X theirs" option should have done this for me, but it did not.

git merge -s recursive -X theirs master

error: 'merge' is not possible because you have unmerged files. hint: Fix them up in the work tree, hint: and then use 'git add/rm ' as hint: appropriate to mark resolution and make a commit, hint: or use 'git commit -a'. fatal: Exiting because of an unresolved conflict.

Android get Current UTC time

System.currentTimeMillis() does give you the number of milliseconds since January 1, 1970 00:00:00 UTC. The reason you see local times might be because you convert a Date instance to a string before using it. You can use DateFormats to convert Dates to Strings in any timezone:

DateFormat df = DateFormat.getTimeInstance();
df.setTimeZone(TimeZone.getTimeZone("gmt"));
String gmtTime = df.format(new Date());

Also see this related question.

Flask example with POST

Before actually answering your question:

Parameters in a URL (e.g. key=listOfUsers/user1) are GET parameters and you shouldn't be using them for POST requests. A quick explanation of the difference between GET and POST can be found here.

In your case, to make use of REST principles, you should probably have:

http://ip:5000/users
http://ip:5000/users/<user_id>

Then, on each URL, you can define the behaviour of different HTTP methods (GET, POST, PUT, DELETE). For example, on /users/<user_id>, you want the following:

GET /users/<user_id> - return the information for <user_id>
POST /users/<user_id> - modify/update the information for <user_id> by providing the data
PUT - I will omit this for now as it is similar enough to `POST` at this level of depth
DELETE /users/<user_id> - delete user with ID <user_id> 

So, in your example, you want do a POST to /users/user_1 with the POST data being "John". Then the XPath expression or whatever other way you want to access your data should be hidden from the user and not tightly couple to the URL. This way, if you decide to change the way you store and access data, instead of all your URL's changing, you will simply have to change the code on the server-side.

Now, the answer to your question: Below is a basic semi-pseudocode of how you can achieve what I mentioned above:

from flask import Flask
from flask import request

app = Flask(__name__)

@app.route('/users/<user_id>', methods = ['GET', 'POST', 'DELETE'])
def user(user_id):
    if request.method == 'GET':
        """return the information for <user_id>"""
        .
        .
        .
    if request.method == 'POST':
        """modify/update the information for <user_id>"""
        # you can use <user_id>, which is a str but could
        # changed to be int or whatever you want, along
        # with your lxml knowledge to make the required
        # changes
        data = request.form # a multidict containing POST data
        .
        .
        .
    if request.method == 'DELETE':
        """delete user with ID <user_id>"""
        .
        .
        .
    else:
        # POST Error 405 Method Not Allowed
        .
        .
        .

There are a lot of other things to consider like the POST request content-type but I think what I've said so far should be a reasonable starting point. I know I haven't directly answered the exact question you were asking but I hope this helps you. I will make some edits/additions later as well.

Thanks and I hope this is helpful. Please do let me know if I have gotten something wrong.

Check if a String is in an ArrayList of Strings

The List interface already has this solved.

int temp = 2;
if(bankAccNos.contains(bakAccNo)) temp=1;

More can be found in the documentation about List.

How to use BeginInvoke C#

I guess your code relates to Windows Forms.
You call BeginInvoke if you need something to be executed asynchronously in the UI thread: change control's properties in most of the cases.
Roughly speaking this is accomplished be passing the delegate to some procedure which is being periodically executed. (message loop processing and the stuff like that)

If BeginInvoke is called for Delegate type the delegate is just invoked asynchronously.
(Invoke for the sync version.)

If you want more universal code which works perfectly for WPF and WinForms you can consider Task Parallel Library and running the Task with the according context. (TaskScheduler.FromCurrentSynchronizationContext())

And to add a little to already said by others: Lambdas can be treated either as anonymous methods or expressions.
And that is why you cannot just use var with lambdas: compiler needs a hint.

UPDATE:

this requires .Net v4.0 and higher

// This line must be called in UI thread to get correct scheduler
var scheduler = System.Threading.Tasks.TaskScheduler.FromCurrentSynchronizationContext();

// this can be called anywhere
var task = new System.Threading.Tasks.Task( () => someformobj.listBox1.SelectedIndex = 0);

// also can be called anywhere. Task  will be scheduled for execution.
// And *IF I'm not mistaken* can be (or even will be executed synchronously)
// if this call is made from GUI thread. (to be checked) 
task.Start(scheduler);

If you started the task from other thread and need to wait for its completition task.Wait() will block calling thread till the end of the task.

Read more about tasks here.

Ruby: How to convert a string to boolean

I have a little hack for this one. JSON.parse('false') will return false and JSON.parse('true') will return true. But this doesn't work with JSON.parse(true || false). So, if you use something like JSON.parse(your_value.to_s) it should achieve your goal in a simple but hacky way.

How to set a border for an HTML div tag

As per the W3C:

Since the initial value of the border styles is 'none', no borders will be visible unless the border style is set.

In other words, you need to set a border style (e.g. solid) for the border to show up. border:thin only sets the width. Also, the color will by default be the same as the text color (which normally doesn't look good).

I recommend setting all three styles:

style="border: thin solid black"

Android - setOnClickListener vs OnClickListener vs View.OnClickListener

  1. First of all, there is no difference between View.OnClickListener and OnClickListener. If you just use View.OnClickListener directly, then you don't need to write-

    import android.view.View.OnClickListener

  2. You set an OnClickListener instance (e.g. myListener named object)as the listener to a view via setOnclickListener(). When a click event is fired, that myListener gets notified and it's onClick(View view) method is called. Thats where we do our own task. Hope this helps you.

How to provide a mysql database connection in single file in nodejs

You could create a db wrapper then require it. node's require returns the same instance of a module every time, so you can perform your connection and return a handler. From the Node.js docs:

every call to require('foo') will get exactly the same object returned, if it would resolve to the same file.

You could create db.js:

var mysql = require('mysql');
var connection = mysql.createConnection({
    host     : '127.0.0.1',
    user     : 'root',
    password : '',
    database : 'chat'
});

connection.connect(function(err) {
    if (err) throw err;
});

module.exports = connection;

Then in your app.js, you would simply require it.

var express = require('express');
var app = express();
var db = require('./db');

app.get('/save',function(req,res){
    var post  = {from:'me', to:'you', msg:'hi'};
    db.query('INSERT INTO messages SET ?', post, function(err, result) {
      if (err) throw err;
    });
});

server.listen(3000);

This approach allows you to abstract any connection details, wrap anything else you want to expose and require db throughout your application while maintaining one connection to your db thanks to how node require works :)

How do you count the elements of an array in java

What I think you may want is an ArrayList<Integer> instead of an array. This will allow you do to:

ArrayList<Integer> arr = new ArrayList<Integer>(20);
System.out.println(arr.size());

The output will be 0.

Then, you can add things to the list, and it will keep track of the count for you. (It will also grow the size of the backing storage as you need as well.)

Pass Model To Controller using Jquery/Ajax

Use the following JS:

$(document).ready(function () {
    $("#btnsubmit").click(function () {

             $.ajax({
                 type: "POST",
                 url: '/Plan/PlanManage',     //your action
                 data: $('#PlanForm').serialize(),   //your form name.it takes all the values of model               
                 dataType: 'json',
                 success: function (result) {
                     console.log(result);
                 }
             })
        return false;
    });
});

and the following code on your controller:

[HttpPost]
public string PlanManage(Plan objplan)  //model plan
{
}

How to loop through all the properties of a class?

Here's another way to do it, using a LINQ lambda:

C#:

SomeObject.GetType().GetProperties().ToList().ForEach(x => Console.WriteLine($"{x.Name} = {x.GetValue(SomeObject, null)}"));

VB.NET:

SomeObject.GetType.GetProperties.ToList.ForEach(Sub(x) Console.WriteLine($"{x.Name} = {x.GetValue(SomeObject, Nothing)}"))

How to recursively delete an entire directory with PowerShell 2.0?

I took another approach inspired by @john-rees above - especially when his approach started to fail for me at some point. Basically recurse the subtree and sort files by their path-length - delete from longest to the shortest

Get-ChildItem $tfsLocalPath -Recurse |  #Find all children
    Select-Object FullName,@{Name='PathLength';Expression={($_.FullName.Length)}} |  #Calculate the length of their path
    Sort-Object PathLength -Descending | #sort by path length descending
    %{ Get-Item -LiteralPath $_.FullName } | 
    Remove-Item -Force

Regarding the -LiteralPath magic, here's another gotchya that may be hitting you: https://superuser.com/q/212808

What does void do in java?

void means it returns nothing. It does not return a string, you write a string to System.out but you're not returning one.

You must specify what a method returns, even if you're just saying that it returns nothing.

Technically speaking they could have designed the language such that if you don't write a return type then it's assumed to return nothing, however making you explicitly write out void helps to ensure that the lack of a returned value is intentional and not accidental.

Count number of rows matching a criteria

With dplyr package, Use

 nrow(filter(mydata, sCode == "CA")),

All the solutions provided here gave me same error as multi-sam but that one worked.

How to print without newline or space?

...you do not need to import any library. Just use the delete character:

BS=u'\0008' # the unicode for "delete" character
for i in range(10):print(BS+"."),

this removes the newline and the space (^_^)*

How can I get the count of milliseconds since midnight for the current?

Do you mean?

long millis = System.currentTimeMillis() % 1000;

BTW Windows doesn't allow timetravel to 1969

C:\> date
Enter the new date: (dd-mm-yy) 2/8/1969
The system cannot accept the date entered.

Include in SELECT a column that isn't actually in the database

You may want to use:

SELECT Name, 'Unpaid' AS Status FROM table;

The SELECT clause syntax, as defined in MSDN: SELECT Clause (Transact-SQL), is as follows:

SELECT [ ALL | DISTINCT ]
[ TOP ( expression ) [ PERCENT ] [ WITH TIES ] ] 
<select_list> 

Where the expression can be a constant, function, any combination of column names, constants, and functions connected by an operator or operators, or a subquery.

Bootstrap - dropdown menu not working?

Double importing jquery can cause Error

<script src="static/public/js/jquery/jquery.min.js"></script>

OR

<script src="https://code.jquery.com/jquery-3.4.1.slim.min.js" integrity="" crossorigin="anonymous"></script>

Child inside parent with min-height: 100% not inheriting height

Just to keep this subject complete, I found a solution not explored Here using Fixed position.

No Overflow

_x000D_
_x000D_
html, body, .wrapper, .parent, .child {_x000D_
  position: fixed;_x000D_
  top: 0; _x000D_
  bottom: 0;_x000D_
  left: 0;_x000D_
  right: 0;_x000D_
  margin: 0;_x000D_
  padding: 0;_x000D_
  height: 100%;_x000D_
}_x000D_
_x000D_
.child {_x000D_
  overflow: auto;_x000D_
  background: gray;_x000D_
}_x000D_
_x000D_
.height-50 {_x000D_
  height: 50%;_x000D_
  width: 5em;_x000D_
  margin: 10px auto;_x000D_
  background: cyan;_x000D_
}
_x000D_
<div class="wrapper">_x000D_
  <div class="parent">_x000D_
    <div class="child">_x000D_
      _x000D_
      <div class="height-50"></div>_x000D_
      _x000D_
    </div>_x000D_
  </div>_x000D_
</div>
_x000D_
_x000D_
_x000D_

With Overflow

_x000D_
_x000D_
html, body, .wrapper, .parent, .child {_x000D_
  position: fixed;_x000D_
  top: 0; _x000D_
  bottom: 0;_x000D_
  left: 0;_x000D_
  right: 0;_x000D_
  margin: 0;_x000D_
  padding: 0;_x000D_
  height: 100%;_x000D_
}_x000D_
_x000D_
.child {_x000D_
  overflow: auto;_x000D_
  background: gray;_x000D_
}_x000D_
_x000D_
.height-150 {_x000D_
  height: 150%;_x000D_
  width: 5em;_x000D_
  margin: 10px auto;_x000D_
  background: cyan;_x000D_
}
_x000D_
<div class="wrapper">_x000D_
  <div class="parent">_x000D_
    <div class="child">_x000D_
      _x000D_
      <div class="height-150"></div>_x000D_
      _x000D_
    </div>_x000D_
  </div>_x000D_
</div>
_x000D_
_x000D_
_x000D_

Jquery- Get the value of first td in table

$(this).parent().siblings(":first").text()

parent gives you the <td> around the link,

siblings gives all the <td> tags in that <tr>,

:first gives the first matched element in the set.

text() gives the contents of the tag.

How to apply !important using .css()?

Another easy method to solve this issue adding the style attribute:

$('.selector').attr('style', 'width:500px !important');

What is the correct value for the disabled attribute?

I just tried all of these, and for IE11, the only thing that seems to work is disabled="true". Values of disabled or no value given didnt work. As a matter of fact, the jsp got an error that equal is required for all fields, so I had to specify disabled="true" for this to work.

Vim for Windows - What do I type to save and exit from a file?

Use:

:wq!

The exclamation mark is used for overriding read-only mode.

How to add a class to body tag?

Well, you're going to want document.location. Do some sort of string manipulation on it (unless jQuery has a way to avoid that work for you) and then

$(body).addClass(foo);

I know this isn't the complete answer, but I assume you can work the rest out :)

How can I remove the outline around hyperlinks images?

If the solution above doesn't work for anyone. Give this a try as well

a {
 box-shadow: none;
}

What is the difference between lower bound and tight bound?

If I were lazy, I could say that binary search on a sorted array is O(n2), O(n3), and O(2n), and I would be technically correct in every case.

We can use o-notation ("little-oh") to denote an upper bound that is not asymptotically tight. Both big-oh and little-oh are similar. But, big-oh is likely used to define asymptotically tight upper bound.

App.settings - the Angular way?

Here's my solution, loads from .json to allow changes without rebuilding

import { Injectable, Inject } from '@angular/core';
import { Http } from '@angular/http';
import { Observable } from 'rxjs/Observable';
import { Location } from '@angular/common';

@Injectable()
export class ConfigService {

    private config: any;

    constructor(private location: Location, private http: Http) {
    }

    async apiUrl(): Promise<string> {
        let conf = await this.getConfig();
        return Promise.resolve(conf.apiUrl);
    }

    private async getConfig(): Promise<any> {
        if (!this.config) {
            this.config = (await this.http.get(this.location.prepareExternalUrl('/assets/config.json')).toPromise()).json();
        }
        return Promise.resolve(this.config);
    }
}

and config.json

{
    "apiUrl": "http://localhost:3000/api"
}