58
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12
answers
923
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Why doesn't GCC optimize a*a*a*a*a*a to (a*a*a)*(a*a*a)?
I am doing some numerical optimization on a scientific application. One thing I noticed is that GCC will optim
52
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3
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1.1K
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Why does Python's hash of infinity have the digits of π?
The hash of infinity in Python has digits matching pi: >>> inf = float('inf') >>>
62
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7
answers
937
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Why is division in Ruby returning an integer instead of decimal value?
For example: 9 / 5 #=> 1 but I expected 1.8. How can I get the correct decimal (non-integer) result? Wh
63
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21
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2.4K
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Why can't decimal numbers be represented exactly in binary?
There have been several questions posted to SO about floating-point representation. For example, the decimal n
61
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30
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1.4K
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Is floating point math broken?
Consider the following code: 0.1 + 0.2 == 0.3 -> false 0.1 + 0.2 -> 0.30000000000000004
53
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6
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1.4K
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Why is 24.0000 not equal to 24.0000 in MATLAB?
I am writing a program where I need to delete duplicate points stored in a matrix. The problem is that when it
55
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4
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1.3K
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Function for 'does matrix contain value X?'
Is there a built in MATLAB function to find out if a matrix contains a certain value? (ala PHP's in_array
50
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2
answers
735
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In MATLAB, are variables REALLY double-precision by default?
This question arose out of something strange that I noticed after investigating this question further... I al
57
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29
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1.5K
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How do I parse a string to a float or int?
In Python, how can I parse a numeric string like "545.2222" to its corresponding float value, 545.2222? Or par
