ACh FN$ASIN calculate arcsine
Input Floating-point argument on the stack.
Output Floating-point result on the stack.

Returns the arcsine in radians of the floating-point number on the run-time stack.

The stack pointer (RTA_SP) remains unchanged.

See also: technical manual > utility system services > floating point numbers


Example The following code returns the arcsine of 0.5 in FN_RESULT.
        LDD     RTA_SP:
        SUBD    #8              ;make room for argument on stack
        STD     RTA_SP:         ;D now has destination for UT$CPYB
        LDX     #8              ;length for copying argument
        STX     UTW_S0:
        LDX     #FN_ARG         ;source address for UT$CPYB
        OS      UT$CPYB         ;copy argument to stack
        OS      FN$ASIN
        BCS     ERROR1
        LDX     RTA_SP:         ;source address for copying result
        LDD     #8
        STD     UTW_S0:         ;length for copying result
        ADDD    RTA_SP:         ;add 8 to stack pointer
        STD     RTA_SP:         ;restore stack pointer
        LDD     #FN_RESULT      ;destination for copy
        OS      UT$CPYB

        DB      0,0,0,0,0,50h,-1,0

        .BLKB   8
FN_RESULT will now contain the floating-point result 0.523598775598.
Errors 247 - Bad argument