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How to install Java SDK on CentOS?
...is, the lastest available version may be different.
java-1.7.0-openjdk.x86_64
The above package alone will only install JRE. To also install javac and JDK, the following command will do the trick:
$ yum install java-1.7.0-openjdk*
These packages will be installing (as well as their dependencie...
Is there a math nCr function in python? [duplicate]
...
def nCr(n,r):
f = math.factorial
return f(n) / f(r) / f(n-r)
if __name__ == '__main__':
print nCr(4,2)
In Python 3, use the integer division // instead of / to avoid overflows:
return f(n) // f(r) // f(n-r)
Output
6
...
Abort makefile if variable not set
...
TL;DR: Use the error function:
ifndef MY_FLAG
$(error MY_FLAG is not set)
endif
Note that the lines must not be indented. More precisely, no tabs must precede these lines.
Generic solution
In case you're going to test many variables, it's worth defining an au...
How can we programmatically detect which iOS version is device running on? [duplicate]
...j/CJAMacros/blob/master/CJAMacros/CJAMacros.h
Like this:
#define SYSTEM_VERSION_EQUAL_TO(v) ([[[UIDevice currentDevice] systemVersion] compare:v options:NSNumericSearch] == NSOrderedSame)
#define SYSTEM_VERSION_GREATER_THAN(v) ([[[UIDevice currentDevice] systemVersi...
How can I open a link in a new window?
...
window.open('url', 'window name', 'window settings')
jQuery:
$('a#link_id').click(function(){
window.open('url', 'window name', 'window settings');
return false;
});
You could also set the target to _blank actually.
...
Underscore prefix for property and method names in JavaScript
...d variable to be private was accepted. Chrome 74 ships with this support.
_ prefixed variable names are considered private by convention but are still public.
This syntax tries to be both terse and intuitive, although it's rather different from other programming languages.
Why was the sig...
Change all files and folders permissions of a directory to 644/755
...
One approach could be using find:
for directories
find /desired_location -type d -print0 | xargs -0 chmod 0755
for files
find /desired_location -type f -print0 | xargs -0 chmod 0644
share
|
...
Calendar Recurring/Repeating Events - Best Storage Method
... NAME
1 Sample Event
2 Another Event
And a table called events_meta like this:
ID event_id meta_key meta_value
1 1 repeat_start 1299132000
2 1 repeat_interval_1 432000
With repeat_start being a date with no time as a unix times...
Detect iPad users using jQuery?
... to detect an iPad user by taking a look at the userAgent property:
var is_iPad = navigator.userAgent.match(/iPad/i) != null;
iPhone/iPod Detection
Similarly, the platform property to check for devices like iPhones or iPods:
function is_iPhone_or_iPod(){
return navigator.platform.match(/i(...
Performance of Find() vs. FirstOrDefault() [duplicate]
...ject an anonmyous data item just for compilation
List<\u003C\u003Ef__AnonymousType0<string>> source = Enumerable.ToList(Enumerable.Select(Enumerable.Range(0, 1000000), i =>
{
var local_0 = new
{
Name = Guid.NewGuid().ToString()
};
return local_...