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How do I remove duplicate items from an array in Perl?
..., but if you were to add sorting in this function then it would trump $::a and $::b, wouldn't it?
– vol7ron
Feb 21 '12 at 16:45
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Why I can't change directories using “cd”?
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Shell scripts are run inside a subshell, and each subshell has its own concept of what the current directory is. The cd succeeds, but as soon as the subshell exits, you're back in the interactive shell and nothing ever changed there.
One way to get around this is t...
How to check if an object is a generator object in python?
...ance(gen, (types.GeneratorType, map, filter)) is useful to also detect map and filter. This will still not include other iterables and iterators though.
– jlh
May 2 at 14:32
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Check if a number is int or float
... isinstance(False, (int, float)) = True), I needed not isinstance(n, bool) and isinstance(n, (int, float)) instead
– YTZ
Jun 7 at 16:53
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Regular expression for a hexadecimal number?
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@NiklasB. Your shorthand is only valid if using perl regex, if using POSIX regex, then Steven's solution is the shortest. Either way, Steven's solution works for both perl and POSIX regex.
– David M. Syzdek
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mongoDB/mongoose: unique if not null
...e sparse if you just add a sparse : true to your schema. You have to drop and re-add the index. Dunno if that's expected or a bug.
– Adam A
Jun 5 '12 at 22:34
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Clear the cache in JavaScript
....reload(true) to reload the current page. It will ignore any cached items and retrieve new copies of the page, css, images, JavaScript, etc from the server. This doesn't clear the whole cache, but has the effect of clearing the cache for the page you are on.
However, your best strategy is to vers...
Is Fortran easier to optimize than C for heavy calculations?
...ode that has aliasing is not valid Fortran, but it is up to the programmer and not the compiler to detect these errors. Thus Fortran compilers ignore possible aliasing of memory pointers and allow them to generate more efficient code. Take a look at this little example in C:
void transform (float *...
PHP Regex to check date is in YYYY-MM-DD format
...t answer? This returns true for a number of invalid dates like 2016-02-30 and 2016-09-31
– Graham
Oct 11 '16 at 14:35
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How to reshape data from long to wide format
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+1 and you don't need to rely on external packages, since reshape comes with stats. Not to mention that it's faster! =)
– aL3xa
May 5 '11 at 0:07
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