= private = protected
acos(p1)
Computes the arc cosine of x. Returns 0..PI.
static VALUE math_acos(VALUE obj, VALUE x) { double d0, d; Need_Float(x); errno = 0; d0 = RFLOAT_VALUE(x); d = acos(d0); domain_check(d0, d, "acos"); return DBL2NUM(d); }