Talk:Vigenère cipher/Cryptanalysis: Difference between revisions
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:: It's a good optimization, but a better one might be to avoid allocation of the vector on every function call. Making 'results' function static, passed in by reference, or even file static would all be reasonable options. There's no threading in this program, so thread safety isn't a concern. 'results' is completely recalculated on each call, so there's no need to clear out its contents between calls, either. Finally, it's probably also perfectly appropriate for it to be a pair<char,double> array, rather than a vector, though that's less significant as an optimization as long as per-call reallocation is avoided. --[[User:Short Circuit|Michael Mol]] 18:15, 21 June 2011 (UTC) |
:: It's a good optimization, but a better one might be to avoid allocation of the vector on every function call. Making 'results' function static, passed in by reference, or even file static would all be reasonable options. There's no threading in this program, so thread safety isn't a concern. 'results' is completely recalculated on each call, so there's no need to clear out its contents between calls, either. Finally, it's probably also perfectly appropriate for it to be a pair<char,double> array, rather than a vector, though that's less significant as an optimization as long as per-call reallocation is avoided. --[[User:Short Circuit|Michael Mol]] 18:15, 21 June 2011 (UTC) |
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::: I should have read the code more thoroughly. I didn't notice that the entire vector was being returned out. Pass-by-reference would be useful, there. The data is used by correlation() with the sort() algorithm, so a simple array is inappropriate. std::vector is the better option. However, the data is only used in frequency() and correlation(), so a class-instance std::vector as a buffer still strikes me as a good optimization. --[[User:Short Circuit|Michael Mol]] 18:22, 21 June 2011 (UTC) |
::: I should have read the code more thoroughly. I didn't notice that the entire vector was being returned out. Pass-by-reference would be useful, there. The data is used by correlation() with the sort() algorithm, so a simple array is inappropriate. std::vector is the better option. However, the data is only used in frequency() and correlation(), so a class-instance std::vector as a buffer still strikes me as a good optimization. --[[User:Short Circuit|Michael Mol]] 18:22, 21 June 2011 (UTC) |
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:::: Ok. That makes sense, but what about all the other changes made? [[User:MagiMaster|MagiMaster]] 19:45, 21 June 2011 (UTC) |
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