ceil()
Returns the smallest Integer greater than or equal to float.
1.2.ceil #=> 2 2.0.ceil #=> 2 (-1.2).ceil #=> -1 (-2.0).ceil #=> -2
static VALUE flo_ceil(VALUE num) { double f = ceil(RFLOAT_VALUE(num)); long val; if (!FIXABLE(f)) { return rb_dbl2big(f); } val = (long)f; return LONG2FIX(val); }