大约有 40,000 项符合查询结果(耗时:0.0641秒) [XML]

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Difference between reduce and foldLeft/fold in functional programming (particularly Scala and Scala

...t is both commutative and associative. This means the operation can be parallelized. This distinction is very important for Big Data / MPP / distributed computing, and the entire reason why reduce even exists. The collection can be chopped up and the reduce can operate on each chunk, then the red...
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How to check version of python modules?

I just installed the python modules: construct and statlib with setuptools like this: 25 Answers ...
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If table exists drop table then create it, if it does not exist just create it

...s case than not to cover, see locking note below). Second RENAME ... atomically replaces table definition, refer to MySQL manual for details. At last, DROP ... just cleans up the old table, obviously. Wrapping all statements with something like SELECT GET_LOCK('__upgrade', -1); ... DO RELEASE_LOCK...
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What is the difference between exit and return? [duplicate]

...hat is difference between return and exit statement in C programming when called from anywhere in a C program? 4 Answers ...
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How to measure time in milliseconds using ANSI C?

... Doesn't this measure cpu time and not wall time? – krs013 Feb 1 '15 at 4:53  |  show 1 more comment ...
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Structure padding and packing

.... A note though - unaligned memory access is slower on architectures that allow it (like x86 and amd64), and is explicitly prohibited on strict alignment architectures like SPARC. share | improve t...
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background function in Python

...em is. I've got a function that downloads the image needed and saves it locally. Right now it's run inline with the code that displays a message to the user, but that can sometimes take over 10 seconds for non-local images. Is there a way I could call this function when it's needed, but run it in t...
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UIButton Image + Text IOS

... I see very complicated answers, all of them using code. However, if you are using Interface Builder, there is a very easy way to do this: Select the button and set a title and an image. Note that if you set the background instead of the image then the ima...
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Two way/reverse map [duplicate]

... 1 >>> del d['foo'] >>> d['bar'] Traceback (most recent call last): File "<stdin>", line 7, in <module> KeyError: 'bar' I'm sure I didn't cover all the cases, but that should get you started. ...
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No Swipe Back when hiding Navigation Bar in UINavigationController

... navigationController?.navigationBar.hidden = true does work, but does not allow your change in navigation bar to be hidden. Lastly, it's generally better practice to create a model object that is the UIGestureRecognizerDelegate for your navigation controller. Setting it to a controller in the UINa...