WP 34S and 31S bugs and fixes

[emece67]

I've found another bug, this time in the (XROM) code for the complex gudermannian function. For all arguments it throws an "Illegal Operation" error. Both the real machine and the emulator show it.

Its current code is:

Code:

        XLBL"cpx_gd"
        xIN MONADIC_COMPLEX
        [cmplx]Num 1/2
        [cmplx][times]
        [cmplx]TANH
        [cmplx]ATAN
        [cmplx]RCL+ Z   // incidentally, this should be RCL+ X
        xOUT xOUT_NORMAL

This code uses the definition of the complex gudermannian function:
\[gd(z) = 2\arctan(\tanh{z\over2})\]

The problem is that [cmplx]ATAN is implemented also in XROM, inside another xIN/xOUT environment. As xIN/xOUT cannot be nested this causes the error.

A workaround consists in using a different definition for the complex gudermannian function, namely \[gd(z) = \arcsin(\tanh z)\]
with code:

Code:

        XLBL"cpx_gd"
        xIN MONADIC_COMPLEX
        [cmplx]TANH
        GSB cpx_asin
        xOUT xOUT_NORMAL

Hope this helps, regards.