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Why is a round-trip conversion via a string not safe for a double?

... 178 I found the bug. .NET does the following in clr\src\vm\comnumber.cpp: DoubleToNumber(value, ...
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What does the “map” method do in Ruby?

...e from the block (the original object is unchanged unless you use map!): [1, 2, 3].map { |n| n * n } #=> [1, 4, 9] Array and Range are enumerable types. map with a block returns an Array. map! mutates the original array. Where is this helpful, and what is the difference between map! and each...
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How to add leading zeros?

...of digits to begin with, so let's try a harder example of making powers of 10 width 8 too. anim <- 25499:25504 x <- 10 ^ (0:5) paste (and it's variant paste0) are often the first string manipulation functions that you come across. They aren't really designed for manipulating numbers, but...
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How to check Django version

... 691 Django 1.5 supports Python 2.6.5 and later. If you're under Linux and want to check the Python ...
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How do I profile memory usage in Python?

... 123 This one has been answered already here: Python memory profiler Basically you do something li...
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How random is JavaScript's Math.random?

... 183 Given numbers between 1 and 100. 9 have 1 digit (1-9) 90 have 2 digits (10-99) 1 has 3 digi...
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Jasmine.js comparing arrays

...n() { it('passes if arrays are equal', function() { var arr = [1, 2, 3]; expect(arr).toEqual([1, 2, 3]); }); }); Just for information: toBe() versus toEqual(): toEqual() checks equivalence. toBe(), on the other hand, makes sure that they're the exact same object. ...
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Strange, unexpected behavior (disappearing/changing values) when using Hash default value, e.g. Hash

... 166 First, note that this behavior applies to any default value that is subsequently mutated (e.g....
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Is there a standardized method to swap two variables in Python?

... 401 Python evaluates expressions from left to right. Notice that while evaluating an assignment...
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Resumable downloads when using PHP to send the file?

... 13 Answers 13 Active ...