"Warp" <war### [at] tagpovrayorg> wrote
>: Thus, the second sentence of above paragraph should be like this "These
>: functions usually have discontinuities (i.e. not differentiable)."
>
>  Ok, I'll change that. However, the comment in the parentheses should then
>also be changed (or even removed). A curve or surface can be continuous,
but
>still not differentiable at a certain point. This usually means that
there's
>a sharp point or edge there.

Yes. The comment in the parentheses should be removed,
or "not differentiable" should be changed to "infinite gradient".
# I have not checked my message well before the posting. Sorry.

R. Suzuki

Post a reply to this message