David and Michele Holmgren <holmgrenm@shaw.ca> writes:
> Hi - Here's a short session in which I differentiate a function containing
> sign(x) amongst other things. Does anyone know what the PNZ(...) notation
> means? Many thanks for any insight into this.
Well,
(C1) properties(pnz);
(D1) []
(C2) properties(sign);
(D2) [System Function]
So PNZ is not a function. In fact, it's just one of the possible return
values of SIGN. It's returned when Maxima is not able to give a more
specific answer based on the form of the argument and the context.
(C3) sign(x^2);
(D3) PZ
(C4) sign(-x^2);
(D4) NZ
(C5) sign(0);
(D5) ZERO
(C6) sign(x);
(D6) PNZ
Some related questions were discussed on the mailing list. You might
be interested in reading the thread starting with
http://www.math.utexas.edu/pipermail/maxima/2002/001957.html
Wolfgang
--
wjenkner@inode.at