• asin
• acos
• atan, atan2 (#2)

See also #8.

• log (with base argument)
• ln
• log10

Also their _1p variants (#11).

• sinh
• cosh
• tanh (#1, #6)

• erf
• erfc

• powf
• powi

In case the goal of this crate is to include more fast functions (which I hope), here is some inspiration:
https://www.kvraudio.com/forum/viewtopic.php?f=33&t=464290
https://github.com/herumi/fmath
https://github.com/herumi/xbyak
https://varietyofsound.wordpress.com/2011/02/14/efficient-tanh-computation-using-lamberts-continued-fraction/#more-1929

I'm not sure if these are the best/fastest (for writing audio DSP plugins). It's always a tradeoff between accuracy and speed.
It would be useful to have them in Rust too, when writing audio DSP plugins in Rust.

Potentially also exp2_m1 etc, since packaging that up likely saves a multiplication?

Potentially best implemented in the form of log2_1p, but ln_1p should be exposed too.

• asinh
• acosh
• atanh

• sin
• cos
• sin_cos (potentially saves some computation)
• tan

All of the interesting functions in https://doc.rust-lang.org/std/primitive.f32.html:

• #8 trig
• #9 inverse trig
• #10 exp_m1
• #11 log_1p
• #12 hyperbolic
• #13 inverse hyperbolic
• #14 powers
• #15 other logs

• lgamma
• tgamma

These names are the conventional/libc ones, but it might be nice to break with convention?

There are hardware instructions on X86 for approximate inverse square root and square root which can improved upon via newton's method.
See the for loop at the bottom of bodies_advance here: https://benchmarksgame-team.pages.debian.net/benchmarksgame/program/nbody-rust-7.html
It would look a lot better if this example could be re-written to use purely safe, normal looking rust code.