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Is it better to use std::memcpy() or std::copy() in terms to performance?

...y. I wrote a C++ SHA-2 implementation. In my test, I hash 5 strings using all four SHA-2 versions (224, 256, 384, 512), and I loop 300 times. I measure times using Boost.timer. That 300 loop counter is enough to completely stabilize my results. I ran the test 5 times each, alternating between the m...
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How to get all subsets of a set? (powerset)

...owerset([4, 5, 6]))) Using yield means that you do not need to calculate all results in a single piece of memory. Precalculating the masks outside the main loop is assumed to be a worthwhile optimization. share | ...
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Python Process Pool non-daemonic?

...to create a python Pool that is non-daemonic? I want a pool to be able to call a function that has another pool inside. 8 A...
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Ways to implement data versioning in MongoDB

... approach would be to store diffs. Because the display of these diffs is really a special action, I would put the diffs in a different "history" collection. I would use the different collection to save memory space. You generally don't want a full history for a simple query. So by keeping the histo...
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What does Python's eval() do?

...less until you find a need for it. It is used on sites like codepad.org to allow you to execute scripts in a test environment. eval() can also be used to execute highly-dynamic code, but you should make yourself fully aware of the security and performance risks before using it. ...
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python pandas remove duplicate columns

...he given example, the returned value would be [False,False,True]. Pandas allows one to index using boolean values whereby it selects only the True values. Since we want to keep the unduplicated columns, we need the above boolean array to be flipped (ie [True, True, False] = ~[False,False,True]) F...
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How do I PHP-unserialize a jQuery-serialized form?

.... You do indeed need to parse the string that serialize returns. See the really popular answer below. – Isaac Lubow Mar 1 '19 at 2:17 add a comment  |  ...
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Determine whether an array contains a value [duplicate]

... } return index; }; } return indexOf.call(this, needle) > -1; }; You can use it like this: var myArray = [0,1,2], needle = 1, index = contains.call(myArray, needle); // true CodePen validation/usage ...
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Difference between dispatch_async and dispatch_sync on serial queue?

... I do mean serial execution. In point of view that all tasks are executed serial regards to other tasks in the same queue. Of cause it still can be concurrent regards to other queues. It is the whole point of GCD that tasks can be dispatched and executed concurrently. ...
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Combining node.js and Python

... We are highly concerned about speed, what is the most elegant way how to call a Python "worker" from node.js in an asynchronous non-blocking way? ...