Posts: 3,229

Threads: 42

Joined: Jul 2006

It would be easy enough to include a user code programme to calculate this branch of the W function in the device -- for real arguments only. I'd guess 100 or so bytes of precious flash.

Alternatively, use this program:

01 LBL'W[sub-1]'

02 LocR 02

03 STO .02

04 +/-

05 1/x

06 STO .00

07 STO .01

08 LN

09 RCL[times] .00

10 RCL .01

11 x[<->] Y

12 -

13 x=0?

14 SKIP 03

15 DROP

16 RCL L

17 BACK 10

18 DROP

19 RCL L

20 RCL/ .00

21 +/-

22 x[<->] .02

23 STO L

24 x[<->] .02

25 RTN

Store it in one of the flash segments and you've got the W_{-1} function. It behaves like a keyboard command in that Last X is set properly and the stack is not damaged. The argument range is not correctly validated however.

- Pauli