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Why is the shovel operator (
...
Proof:
a = 'foo'
a.object_id #=> 2154889340
a << 'bar'
a.object_id #=> 2154889340
a += 'quux'
a.object_id #=> 2154742560
So << alters the original string rather than creating a new one. The reason for this is that in ruby a += b is syntactic short...
Why am I seeing “TypeError: string indices must be integers”?
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answered May 20 '11 at 21:16
TamásTamás
42.9k1111 gold badges9090 silver badges118118 bronze badges
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How do I get the full path to a Perl script that is executing?
...during execution. I discovered that depending on how you call the script $0 varies and sometimes contains the fullpath+filename and sometimes just filename . Because the working directory can vary as well I can't think of a way to reliably get the fullpath+filename of the script.
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Transposing a 2D-array in JavaScript
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210
array[0].map((_, colIndex) => array.map(row => row[colIndex]));
map calls a provided ...
Automatically update version number
...ld but I'm not sure on how to enable this functionality in Visual Studio (2005/2008). I have tried to specify the AssemblyVersion as 1.0.* but it doesn't get me exactly what I want.
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CGContextDrawImage draws image upside down when passed UIImage.CGImage
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Instead of
CGContextDrawImage(context, CGRectMake(0, 0, 145, 15), image.CGImage);
Use
[image drawInRect:CGRectMake(0, 0, 145, 15)];
In the middle of your begin/end CGcontext methods.
This will draw the image with the correct orientation into your current image context...
How to swap two variables in JavaScript
...swap the values of two variables.
Given variables a and b:
b = [a, a = b][0];
Demonstration below:
var a=1,
b=2,
output=document.getElementById('output');
output.innerHTML="<p>Original: "+a+", "+b+"</p>";
b = [a, a = b][0];
output.innerHTML+="<p>Swapped: ...
How to reshape data from long to wide format
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answered May 4 '11 at 23:20
ChaseChase
59.5k1515 gold badges131131 silver badges157157 bronze badges
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An efficient way to transpose a file in Bash
..." "a[i,j];
}
print str
}
}' file
output
$ more file
0 1 2
3 4 5
6 7 8
9 10 11
$ ./shell.sh
0 3 6 9
1 4 7 10
2 5 8 11
Performance against Perl solution by Jonathan on a 10000 lines file
$ head -5 file
1 0 1 2
2 3 4 5
3 6 7 8
4 9 10 11
1 0 1 2
$ wc -l < file
10000
$ ti...
Understanding how recursive functions work
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107
I think the confusion is stemming from thinking of it as "the same function" being called many ...