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A comment on Exact numeric nth derivatives. Parent comment

Re:Exact numeric nth derivatives by 30thElement on Thursday October 24, 2013 @02:45PM (#6607091)
If I remember correctly, the most efficient algorithms have a ridiculously large constant factor, to the point where you don't have enough RAM to even store the matrix, let alone do anything with it.
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Re:Exact numeric nth derivatives by rcthompson on Thursday October 24, 2013 @05:14PM (#6608020)
That's not what GP is talking about. Those algorithms are the sub-cubic ones, the ones that are O(x^2.something). GP is talking about an algorithm that is still O(n^3), but is not just a straight translation of the matrix multiplication formula into code, but rather does things in a way that is more friendly to the CPU cache, resulting in significant speed gains.
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