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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...
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....
JavaScript click event listener on class
...
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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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......
Embed SVG in SVG?
...nteresting observation: the latest versions of Firefox, Chrome, and Safari all show only one level of recursion (two dots) using the above. However, if you save the above as "a.svg" and change the image to "b.svg", and then also save it as "b.svg" with the image referencing "a.svg", then Firefox wil...
Make Vim show ALL white spaces as a character
I can't find a way to make Vim show all white spaces as a character.
All I found was about tabs, trailing spaces etc.
23 An...
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++?
...
std::atan2 allows calculating the arctangent of all four quadrants. std::atan only allows calculating from quadrants 1 and 4.
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Disable Auto Zoom in Input “Text” tag - Safari on iPhone
...t-size for form elements is 11px (at least in Chrome and Safari).
Additionally, the select element needs to have the focus pseudo-class attached.
input[type="color"],
input[type="date"],
input[type="datetime"],
input[type="datetime-local"],
input[type="email"],
input[type="month"],
input[type="num...
Constructor overloading in Java - best practice
...onstructors as simple as possible, and the simplest way is that they only call this(...). That way you only need to check and handle the parameters once and only once.
public class Simple {
public Simple() {
this(null);
}
public Simple(Resource r) {
this(r, null);
...