Compute the EV more efficiently#7
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edgar-bonet wants to merge 2 commits intoLexOptical:masterfrom
edgar-bonet:cheap-log
Open
Compute the EV more efficiently#7edgar-bonet wants to merge 2 commits intoLexOptical:masterfrom edgar-bonet:cheap-log
edgar-bonet wants to merge 2 commits intoLexOptical:masterfrom
edgar-bonet:cheap-log
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Computing the logarithm is expensive on the AVR. On the other hand, the integer part of the base-2 logarithm is just the exponent field of the floating point representation, which is trivial to retrieve. This commit replaces multiple calls to the full-blown logarithm by a cheap function, based on frexp(), which returns the base-2 logarithm rounded to the nearest integer.
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Computing the logarithm is expensive on the AVR. On the other hand, the integer part of the base-2 logarithm is just the exponent field of the floating point representation, which is trivial to retrieve.
This commit replaces multiple calls to the full-blown logarithm by a cheap function, based on
frexp(), which returns the base-2 logarithm rounded to the nearest integer.