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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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impr...
SVG: text inside rect
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Is there a way to not have to manually set height and width on the rect?
– George Mauer
Dec 20 '12 at 17:01
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Iteration over std::vector: unsigned vs signed index variable
... use difference_type? sizeof is defined to return size_t :) i don't understand you. if i were to subtract pointers from each other, difference_type would be the right choice.
– Johannes Schaub - litb
Jan 4 '09 at 9:38
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ld cannot find an existing library
...too. This way, you can have several versions of a library in your system, and if an application needs a specific one, it can link to it, while in general, the newest one is chosen by symlink. I do not know why this symlink was missing.
– Svante
Dec 3 '08 at 1...
How do I sort strings alphabetically while accounting for value when a string is numeric?
I'm trying to sort an array of numbers that are strings and I'd like them to sort numerically.
19 Answers
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Center image horizontally within a div
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I don't think this is a good idea, and also I believe there's some caveats like margin: auto is dependent on the containing element having a designated width value.
– Jared Farrish
Jun 12 '12 at 0:50
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Is inject the same thing as reduce in ruby?
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Yes, and it's also called fold in many other programming languages and in Mathematics. Ruby aliases a lot in order to be intuitive to programmers with different backgrounds. If you want to use #length on an Array, you can. If you ...
django change default runserver port
...ig.ini . Is there an easier fix than parsing sys.argv inside manage.py and inserting the configured port?
12 Answers
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Convert int to string?
...se type safety. myInt could be anything. Nothing here says take an integer and convert it to a string. myInt could be an object and an object can't be converted to a string. That's known at compile time, but it wouldn't even raise a runtime exception it would just allow bad data.
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Rails 3 migrations: Adding reference column?
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EDIT: This is an outdated answer and should not be applied for Rails 4.x+
You don't need to add references when you can use an integer id to your referenced class.
I'd say the advantage of using references instead of a plain integer is that the model will ...