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How do I test if a variable is a number in Bash?
... the regex appropriately; for instance:
^[0-9]+([.][0-9]+)?$
...or, to handle numbers with a sign:
^[+-]?[0-9]+([.][0-9]+)?$
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How can I apply a function to every row/column of a matrix in MATLAB?
...
Many built-in operations like sum and prod are already able to operate across rows or columns, so you may be able to refactor the function you are applying to take advantage of this.
If that's not a viable option, one way to do it is to collect the rows or c...
Difference between save and saveAndFlush in Spring data jpa
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On saveAndFlush, changes will be flushed to DB immediately in this command. With save, this is not necessarily true, and might stay just in memory, until flush or commit commands are issued.
But be aware, that even if you flush th...
How to find the 'sizeof' (a pointer pointing to an array)?
...pointing to. There are tricks, like ending the array with a known out-of-band value and then counting the size up until that value, but that's not using sizeof().
Another trick is the one mentioned by Zan, which is to stash the size somewhere. For example, if you're dynamically allocating the a...
How to add line breaks to an HTML textarea?
...text.replace(/\r?\n/g, '<br />');
UPDATE
Since many of the comments and my own experience have show me that this <br>
solution is not working as expected here is an example of how to append a new line to a textarea using '\r\n'
function log(text) {
var txtArea ;
txtArea = docum...
How To Test if Type is Primitive
...at we can think that are primitives, but they aren´t, for example Decimal and String.
Edit 1: Added sample code
Here is a sample code:
if (t.IsPrimitive || t == typeof(Decimal) || t == typeof(String) || ... )
{
// Is Primitive, or Decimal, or String
}
Edit 2: As @SLaks comments, there are ...
Why does this Java code compile?
...ce by attempting to compile
int x = (x = 1) + x;
as a field declaration and as a local variable declaration. The former will fail, but the latter will succeed, because of the difference in semantics.
Introduction
First off, the rules for field and local variable initializers are very different....
What does “javascript:void(0)” mean?
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The void operator evaluates the given
expression and then returns undefined.
The void operator is often used merely
to obtain the undefined primitive
value, usually using “void(0)” (which
is equivalent to “void 0”). In these
cases, the global variable u...
Command prompt won't change directory to another drive
I'm trying to compile some java (learning java currently), and to do so I need to change command-prompt's directory (using javac).
...
How to get evaluated attributes inside a custom directive
...he old answers for future reference as long as they remain related. Latest and best answer comes first.
Better answer:
Directives in angularjs are very powerful, but it takes time to comprehend which processes lie behind them.
While creating directives, angularjs allows you to create an isolated sco...