#73 sfreverse opt=v (virtual reverse - axis only - not data)

[Anonymous]

Virtual Reverse for sfreverse.
To create an option to not really reverse the data, only the labels. Using opt=v in sfreverse.
That is usefully, when correcting the action of sfreverse opt=i (reversing the data but not the axis). The latter is often needed for codes that break down with negative axis increments. But it would be nice to easily correct that 'partial reverse', by piping the data through sfreverse once more with opt=v, after passing through the main prosessing code.

It following should then create the same data:

in < sfreverse > out
in < sfreverse opt=i | sfreverse opt=v > out

Cheers,
Sjoerd.