hex.count_bits¶
dst[:small_n] = x[:n].#on-bits
x is hex.vec n, and dst is hex.vec small_n.
small_n (it’s 2 for 16-255 bit-numbers) is the smallest number of bits that can hold the number n: ((#(n*4))+3)/4
Signature¶
def count_bits n, dst, x { ... }
Defined in hex/math_basic.fj — lines 82–85 (view on GitHub).
Complexity¶
Time:
n(2.27@-1)Space:
n(3.5@+135) // on 16-255 bit-numbers. (a bit bigger on bigger numbers).
See the complexity glossary for what @, w, dw, dbit, n mean.