[cabirum]

Profiling results:

- initial time: 49s

- replacing default thread-safe RNG with rand.New sliced 6 seconds off. (the default RNG uses mutexes), = 43s

- use float64 instead of float32 and remove many type conversions. Another two seconds off. = 41s.

As others suggested, go still lacks many compile time optimizations and the implementation could be improved.

[weberc2]

I did some profiling too--I shaved off 10-15s by using the C xorshift implementation instead of rand.Float32() (which spends a lot of time locking a mutex).