It appears you don't have a PDF plugin for this browser. You can click here to download the reference manual.
0.5-0 by Oliver Flasch, 11 years ago
https://rsymbolic.org/projects/show/twiddler
Browse source code at https://github.com/cran/twiddler
Authors: Oliver Flasch , Olaf Mersmann
Documentation: PDF Manual
GPL-2 license
Depends on tcltk
See at CRAN