# Math routines

abs ( n -- n )
  If n is negative, yield -n.

isqrt ( n -- n )
  Return the integer square root of n. Example: 27 isqrt --> 5

log2mod ( n -- mod n )
  Return the logarithm of n to the base 2 as well as the modulo of that
  operation. Example: $103 log2 yields n=8 mod=3

log2 ( n -- n )
  Same as log2mod, but without the modulo.

log2# ( n -- n )
  Same as log2, but yields an error if modulo is not zero.

pow2? ( n -- f )
  Is n a power of 2?

pow2 ( n -- n )
  Return 2 to the power of n.

roundup ( n divisor -- n )
  Round "n" up to the nearest "divisor" step. Examples:
  7 4 roundup --> 8
  15 5 roundup --> 15

rounddown ( n divisor -- n )
  Round "n" down to the nearest "divisor" step. Examples:
  7 4 rounddown --> 4
  15 5 rounddown --> 15

## C API

int abs(int n);
uint isqrt(uint n);
uint log2(uint n);
uint roundup(uint div, uint n);
uint rounddown(uint div, uint n);