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How do I check if a number evaluates to infinity?
...
if (result == Number.POSITIVE_INFINITY || result == Number.NEGATIVE_INFINITY)
{
// ...
}
You could possibly use the isFinite function instead, depending on how you want to treat NaN. isFinite returns false if your number is POSITIVE_INFINITY, NEGAT...
jQuery AJAX file upload PHP
...ript to look like this:
$('#upload').on('click', function() {
var file_data = $('#sortpicture').prop('files')[0];
var form_data = new FormData();
form_data.append('file', file_data);
alert(form_data);
$.ajax({
url: 'uploa...
How to refer to relative paths of resources when working with a code repository
...Try to use a filename relative to the current files path. Example for './my_file':
fn = os.path.join(os.path.dirname(__file__), 'my_file')
In Python 3.4+ you can also use pathlib:
fn = pathlib.Path(__file__).parent / 'my_file'
...
What is the function __construct used for?
I have been noticing __construct a lot with classes. I did a little reading and surfing the web, but I couldn't find an explanation I could understand. I am just beginning with OOP.
...
How do you programmatically set an attribute?
...t:
>>> help(setattr)
Help on built-in function setattr in module __builtin__:
setattr(...)
setattr(object, name, value)
Set a named attribute on an object; setattr(x, 'y', v) is equivalent to
``x.y = v''.
Edit: However, you should note (as pointed out in a comment) that you...
Why do we need virtual functions in C++?
...s to more general). Visa-versa you need an explicit cast, usually a dynamic_cast. Anything else - very prone to undefined behavior so make sure you know what you're doing. To the best of my knowledge, this has not changed since before even C++98.
– Steve314
Jun...
Specify JDK for Maven to use
...r a single invocation of maven?
Temporarily change the value of your JAVA_HOME environment variable.
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How to detect if a script is being sourced
...
This seems to be portable between Bash and Korn:
[[ $_ != $0 ]] && echo "Script is being sourced" || echo "Script is a subshell"
A line similar to this or an assignment like pathname="$_" (with a later test and action) must be on the first line of the script or on the...
Transpose/Unzip Function (inverse of zip)?
...
You could also use izip_longest
– Marcin
Sep 26 '13 at 16:52
4
...
JavaScript pattern for multiple constructors
... b= 'some default value';
if (typeof(a)==='string')
this._constructInSomeWay(a, b);
else if (a instanceof MyType)
this._constructInSomeOtherWay(a, b);
}
You can also access arguments as an array-like to get any further arguments passed in.
If you need more complex ar...