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php is null or empty?
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What you're looking for is:
if($variable === NULL) {...}
Note the ===.
When use ==, as you did, PHP treats NULL, false, 0, the empty string, and empty arrays as equal.
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Map Tiling Algorithm
...RPG with Javascript, using perlin noise heightmaps, then assigning a tile type based on the height of the noise.
5 Answers
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Format numbers to strings in Python
I need to find out how to format numbers as strings. My code is here:
8 Answers
8
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Way to get all alphabetic chars in an array in PHP?
Is there a way to get all alphabetic chars (A-Z) in an array in PHP so I can loop through them and display them?
14 Answers...
“:” (colon) in C struct - what does it mean? [duplicate]
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Those are bit fields. Basically, the number after the colon describes how many bits that field uses. Here is a quote from MSDN describing bit fields:
The constant-expression specifies the width of the field in bits. The
type-specifier for the declar...
Add new row to dataframe, at specific row-index, not appended?
... 13 18
5 4 9 14 19
6 5 10 15 20
If speed is less important than clarity, then @Simon's solution works well:
existingDF <- rbind(existingDF[1:r,],newrow,existingDF[-(1:r),])
> existingDF
V1 V2 V3 V4
1 1 6 11 16
2 2 7 12 17
3 3 8 13 18
4 1 2 3 4
41 4 9 14 19
5 5 10 15 ...
Why is unsigned integer overflow defined behavior but signed integer overflow isn't?
Unsigned integer overflow is well defined by both the C and C++ standards. For example, the C99 standard ( §6.2.5/9 ) states
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Drawing an SVG file on a HTML5 canvas
Is there a default way of drawing an SVG file onto a HTML5 canvas? Google Chrome supports loading the SVG as an image (and simply using drawImage ), but the developer console does warn that resource interpreted as image but transferred with MIME type image/svg+xml .
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Creating a UIImage from a UIColor to use as a background image for UIButton [duplicate]
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I created a category around UIButton to be able to set the background color of the button and set the state. You might find this useful.
@implementation UIButton (ButtonMagic)
- (void)setBackgroundColor:(UIColor *)backgroundColor forState:(U...
Common elements comparison between 2 lists
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answered May 19 '10 at 11:00
SilentGhostSilentGhost
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