Adding normalise to gnuplot

[Jon G. <jo...@th...>]

Hi all,

One feature I've been missing from gnuplot is the ability to normalise a
dataset; that is, scale all values so that they are in [0:1] by dividing
by the maximum value. The attached patch does so by introducing "smooth
normal".

There is (at least) one problem with the patch in its current form:
Smoothing should operate on r, not t, when applied to polar plots.
I'm not entirely sure how this should be implemented though?
Any pointers would be welcome!

The patch does not merge cleanly against gnuplot-4.6.5, but by removing
the documentation change and swapping 
    void gen_interp_frequency __PROTO((struct curve_points *plot));
and
    void mcs_interp __PROTO((struct curve_points *plot));
in the patch file under interpol.h.

Any feedback welcome,
Jon