Hello,
I am new to maxima but find it pretty interesting to learn.
I have tried to do the following:
============= 8< ===============
(%i1) display2d:false;
(%o1) false
(%i2) sqrt((f - z^2/4/f)^2 + (d-z)^2) + sqrt((f - z^2/4/f)^2 + (zp-z)^2);
(%o2) sqrt((zp-z)^2+(f-z^2/(4*f))^2)+sqrt((f-z^2/(4*f))^2+(d-z)^2)
(%i3) taylor(%, [z, zp, d], 0, 4);
(%o3) 2*f+(z^2+(-2*zp-2*d)*z+zp^2+d^2)/(2*f)
+((2*zp+2*d)*z^3+(-5*zp^2-5*d^2)*z^2+(4*zp^3+4*d^3)*z-zp^4-d^4)
/(8*f^3)
(%i4) diff(%, z);
Maxima encountered a Lisp error:
Error in PROGN [or a callee]: Bad plist (($ZP ((4 . 1)) 0
((MULTI G32679 1)) ZP32684
. 5)
($Z ((4 . 1)) 0
((MULTI G32679 1)) Z32685
. 6)
(G32679 ((4 . 1)) 0
((MULTIVAR 4 ($Z $ZP $D)))
G3267932686 . 7))
Automatically continuing.
To reenable the Lisp debugger set *debugger-hook* to nil.
============= >8 ===============
Is it a bug, or am I doing something wrong?
The version of maxima I use is 5.13.0.
BTW, if I 'factor' the result of the taylor expansion,
the 'diff' works after that.
--
Stanislav