[m-users.] Announcement: automatic differentiation in Mercury

[Tomas By]

On Mon, 23 Jan 2023 11:30:42 +0100, Richard O'Keefe wrote:
> I'm familiar with dual numbers
> https://en.wikipedia.org/wiki/Dual_number and have used them, but I
> do not understand the extra parameter in this code and have no
> idea what a 'tape' is.  Where is that described?


https://en.wikipedia.org/wiki/Automatic_differentiation

| a data structure known as a Wengert list (or "tape"),[3][4]

3. R.E. Wengert (1964). "A simple automatic derivative evaluation
   program". Comm. ACM. 7 (8): 463–464. doi:10.1145/355586.364791. S2CID
   24039274.

4. Bartholomew-Biggs, Michael; Brown, Steven; Christianson, Bruce;
   Dixon, Laurence (2000). "Automatic differentiation of
   algorithms". Journal of Computational and Applied Mathematics. 124
   (1–2): 171–190. Bibcode:2000JCoAM.124..171B.
   doi:10.1016/S0377-0427(00)00422-2. hdl:2299/3010.
   
/Tomas