From: Johannes Haataja (
Date: Tue Jul 25 2023 - 14:10:29 CDT

Dear all,
        I wonder if the ellipse.tcl script

is broken?

(Apologies if the matter has been addressed already).

If I run the script (in VMD for LINUXAMD64, version 1.9.4a55) and try
to add an ellipsoid

source ellipse.tcl
draw_ellipsoid 3 1 1 0 0 0 0 0 0 blue

I get the following error

"can't read "fdata_r(0.1256636,3.141590000000007)": no such element in

Apparently the indexes u2 (=u+1) and v2 (=v+1) exceed their max value N
in the last for loop (although it shouldn't happen since in the last
loop u and v are run from 0 to N-1).

Anyhow if one just circularly shifts the indexes (see attachment)
everything seems to run smoothly...

My best,