Thank you Philip
I did all you proposed. The files and directories copied in the correct
path, setting the path in octaverc. / replaced by \\, no directory with a
blank in its name. All these pathes are visual in octaves, tested with
getenv("PATH"). The fiels are found.
No warning messages appear now. but there is no *.png file.
Do I really have to install ghostscript as Michael proposed? Or is the
graphic end qt wrong?
I think you really need ghostscript. The other utilities that you installed are needed for more exotic file formats.
Michael.