Raymond Toy

Oops. The derivatives should use $x and $y. defgrad should probably do more error checking. Maybe make sure every variable in the derivatives start with a $?

Support reading compressed info files

cl-info depends on chipz

Remove separate chipz defsystem

Build chipz for maxima

Add chipz sources as is

1/(1-x^5) can be factored as -1/(x-1)/(x^4+x^3+x^2+x+1), and we can use quad_qawc to compute the integral like so: (%i29) quad_qawc(-1/(x^4+x^3+x^2+x+1),x,1,0,100); (%o29) [0.8648062684772098, 2.8888229703493868e-11, 385, 0] And for [100,inf]`: (%i30) quad_qagi(1/(1-x^5),x,100,inf); (%o30) [- 2.500000000111111e-9, 2.7250808692222103e-18, 225, 0] (%i31) %o29[1]+%o30[1]; (%o31) 0.8648062659772098 That's pretty close.

Maybe? At least in these cases, the expression is real everywhere for real x. Unlike sqrt(sin(x)-1) which is real only for appropriate multiples of pi. I don't know what the answer should be. I almost never use sign for anything myself, and if I do it's usually for a simple variable.