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What is the rationale for all comparisons returning false for IEEE754 NaN values?
Why do comparisons of NaN values behave differently from all other values?
That is, all comparisons with the operators ==, =, where one or both values is NaN returns false, contrary to the behaviour of all other values.
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CSS: 100% font size - 100% of what?
...he percent-value is supposed to be. I understand this is 'the same size in all browsers'. I also read this, for instance:
9...
Why should I not include cpp files and instead use a header?
...would've got from separating your source files in the first place.
Essentially, what #include does is tell the preprocessor to take the entire file you've specified, and copy it into your active file before the compiler gets its hands on it. So when you include all the source files in your project...
How to sum a variable by group
...as "model Frequency by Category" or "Frequency depending on Category". Not all languages use a special operator to define a symbolic function, as done in R here. Perhaps with that "natural-language interpretation" of the tilde operator, it becomes more meaningful (and even intuitive). I personally f...
jquery input select all on focus
I'm using this code to try and select all of the text in the field when a user focuses on the field. What happens is, it selects all for a second, then its unselected and the typing cursor is left where I clicked...
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How do I check that a Java String is not all whitespaces?
...ity of the question :) Also, I rarely use matches(): for performance, I usually store the Pattern in a final static. Pays off if the same code runs frequently.
– Carl Smotricz
Jul 14 '10 at 14:31
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Delete empty lines using sed
... spaces or tabs in your "empty" line. Use POSIX classes with sed to remove all lines containing only whitespace:
sed '/^[[:space:]]*$/d'
A shorter version that uses ERE, for example with gnu sed:
sed -r '/^\s*$/d'
(Note that sed does NOT support PCRE.)
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How to implement common bash idioms in Python? [closed]
...y shell has several sets of features.
The Essential Linux/Unix commands. All of these are available through the subprocess library. This isn't always the best first choice for doing all external commands. Look also at shutil for some commands that are separate Linux commands, but you could proba...
How do I find the next commit in git? (child/children of ref)
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To list all the commits, starting from the current one, and then its child, and so on - basically standard git log, but going the other way in time, use something like
git log --reverse --ancestry-path 894e8b4e93d8f3^..master
wher...
Singular or plural controller and helper names in Rails
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Using plural names for controllers is just a convention.
Plural names usually sound more natural (especially for controllers that are tied directly to a specific model: User -> Users, etc.), but you can use whatever you want.
As for helpers, all helpers are available for all controllers by def...