| Routines

14403: THE 'ARCCOS' FUNCTION (offset 35)

The address of this routine is found in the table of addresses. It is called indirectly via fp_calc_2. This subroutine handles the function ACS X and returns a real number from 0 to π inclusive which is equal to the value in radians of the angle whose cosine is X. This subroutine uses the relation ACS X=π/2-ASN X.
acs | 14403 | RST 40 | X
| 14404 | DEFB 34 | asn: ASN X
| 14405 | DEFB 163 | stk_pi_2: ASN X, π/2
| 14406 | DEFB 3 | subtract: ASN X-π/2
| 14407 | DEFB 27 | negate: π/2-ASN X=ACS X
| 14408 | DEFB 56 | end_calc
| 14409 | RET | Finished: 'last value'=ACS X.