Thx! Now Maple 9.5 behaves as expected. Regards Wilhelm

Thx! Now Maple 9.5 behaves as expected. Regards Wilhelm

I have contributed a similar package to the application center in 2001: http://www.maplesoft.com/applications/app_center_view.aspx?AID=185&CID=4&SCID=9 Title: Symbolic computation of Fourier Series. Regards W.Werner

> m := [seq(evalf(1/4*Pi*k, 3), k = 0 .. 8)]; > fx := cos(x)+2*sin(x); > p0:=plot(fx, x = 0 .. 2*Pi, y = -3 .. 3, tickmarks = ([m, default])): > p1 := plot([arctan(2), y, y = -3 .. 3]); > plots[display](p0, p1); You get addition information by ?tickmarks HTH Wilhelm

Type x:=-1/9; sqrt(x); Then execute worksheet or these statements again ...; by the way: x:=-1; sqrt(x); works properly. This is indeed a serious bug. Regards Wilhelm

Maple 10.03 provides the result you expect... Regards Wilhelm

Check for "cholesky algorithm" in a textbook covering numerical linear algebra. Its implementation is rather straightforward. Regards WW