featurehelp wantedmaths
描述
As I was enjoying the entertaining read that is the IEEE-754 standard for floating point arithmetic, I noticed they recommend some functions (section 9.2), of which we currently lack:
- exp2m1:
2^x-1 - exp10m1:
10^x-1 - log2p1:
log2(1+x)(might want to call thislog21p, to matchlog1p?) - log10p1:
log10(1+x)(similarly,log101p?) - rsqrt:
1/sqrt(x) - compound:
(1+x)^n(pow1p?) - rootn:
x^(1/n) - various inverse trig-pi functions, e.g. atanpi:
atan(x)/pi(somewhat confusingly, not all of these are mentioned in the table, although they are referred to in the text below).
There's also three different "pow" functions: pown for integer exponents, two for handling floating-point exponents pow and powr which seem to differ mostly in how signals are raised, so we could probably wait until #2976 is completed.