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How can I check if a file exists in Perl?
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Test whether something exists at given path using the -e file-test operator.
print "$base_path exists!\n" if -e $base_path;
However, this test is probably broader than you intend. The code above will generate output if a plain file exists at that...
Draw multi-line text to Canvas
A hopefully quick question, but I can't seem to find any examples... I'd like to write multi-line text to a custom View via a Canvas , and in onDraw() I have:
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How to make execution pause, sleep, wait for X seconds in R?
...ction, but ?sleep references a data set. And ?pause and ?wait don't exist.
2 Answers
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How can I check for NaN values?
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math.isnan(x)
Return True if x is a NaN (not a number), and False otherwise.
>>> import math
>>> x = float('nan')
>>> math.isnan(x)
True
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Cast List to List in .NET 2.0
...new int[] { 1,2,3 } );
List<string> l2 = l1.ConvertAll<string>(x => x.ToString());
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Is there an R function for finding the index of an element in a vector?
In R, I have an element x and a vector v . I want to find the first index of an element in v that is equal to x . I know that one way to do this is: which(x == v)[[1]] , but that seems excessively inefficient. Is there a more direct way to do it?
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Why does integer division in C# return an integer and not a float?
...ing point number you would be forced to round the result every time. One example off of the top of my head is changing the base of a number. Calculating each digit involves the integer division of a number along with the remainder, rather than the floating point division of the number.
Because of...
SVG: text inside rect
I want to display some text inside SVG rect . Is it possible?
5 Answers
5
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How can I check if a var is a string in JavaScript?
...ed answer at who is more near to my specific problem, that I've not fully explained.
– vitto
Jun 9 '11 at 0:04
this wo...
How to sort a list of strings numerically?
... you want is:
list1 = ["1","10","3","22","23","4","2","200"]
list1 = [int(x) for x in list1]
list1.sort()
If for some reason you need to keep strings instead of ints (usually a bad idea, but maybe you need to preserve leading zeros or something), you can use a key function. sort takes a named par...