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What is the difference between NaN and None?
... a dictionary. The columns contain strings of numbers and letters. Occasionally there are cases where a cell is empty. In my opinion, the value read to that dictionary entry should be None but instead nan is assigned. Surely None is more descriptive of an empty cell as it has a null value, whe...
How to round up to the nearest 10 (or 100 or X)?
...en just define:
roundUp <- function(x) 10^ceiling(log10(x))
This actually also works when x is a vector:
> roundUp(c(0.0023, 3.99, 10, 1003))
[1] 1e-02 1e+01 1e+01 1e+04
..but if you want to round to a "nice" number, you first need to define what a "nice" number is. The following lets us...
What is the difference between atan and atan2 in C++?
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std::atan2 allows calculating the arctangent of all four quadrants. std::atan only allows calculating from quadrants 1 and 4.
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Determining type of an object in ruby
... the "type" of an object, which is a wobbly term in the Ruby world, is to call object.class.
Since classes can inherit from other classes, if you want to determine if an object is "of a particular type" you might call object.is_a?(ClassName) to see if object is of type ClassName or derived from it....
Obtain form input fields using jQuery?
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$('#myForm').submit(function() {
// get all the inputs into an array.
var $inputs = $('#myForm :input');
// not sure if you wanted this, but I thought I'd add it.
// get an associative array of just the values.
var values = {};
$inputs.each(fun...
Is this a “good enough” random algorithm; why isn't it used if it's faster?
I made a class called QuickRandom , and its job is to produce random numbers quickly. It's really simple: just take the old value, multiply by a double , and take the decimal part.
...
How to check with javascript if connection is local host?
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Isn't there a more general / "catch-all" solution that would also cover cases of using 127.0.0.1, etc.?
– jacobq
Oct 10 '12 at 18:21
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JavaScript click event listener on class
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This works perfectly. Thank you. I actually didn't realise that jQuery did the looping. Great help Anudeep. Here's your working answer: jsfiddle.net/LWda3/2
– 30secondstosam
Oct 29 '13 at 10:33
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How to get hex color value rather than RGB value?
...er inefficiencies. If you're going to declare hexDigits on every function call, at least do it in rgb2hex's function body (not hex's body), so the array is not redefined 3 times per 1 call to rgb2hex. Also learn to use 'var', so you don't pollute the global scope.
– Matt
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Unit Test? Integration Test? Regression Test? Acceptance Test?
...plicable:
Unit Test
A unit test is performed on a self-contained unit (usually a class or method) and should be performed whenever a unit has been implemented or updating of a unit has been completed.
This means it's run whenever you've written a class/method, fixed a bug, changed functionality......