Re: [Plplot-general] Mapping rectangluar data into a polar plot

[<si...@mu...>]

> These two functions working differently due to a slight difference in
> their intent.  The pltr* functions take index values and translate
> them in to plot-world coordinates (ex. (i, j) indexing an element in a
> grid -> (x, y) position in plot space).
>
> plstransform takes a coordinate (ex. a radius and an angle for polar
> data) and translates this in to plot world (x, y) coordinates.  The
> mapform function callback used in plmap or plmeridians works similarly
> (see example 19).
>
> These two (pltr* functions and plstranform) can be used together for
> more complicated coordinate transformation purposes.
>

It is highly likely that I am approaching the problem from the wrong
direction, and perhaps another tack would be more fruitful.

What I am attempting to do is represents data sets both in rectangular and
polar for, hopefully auto-magically switching between them.

A lot of the data I have is related to GPS satellites (value, azimuth,
elevation) and I would like to parse it, then plot in rectangular/polar.
For example the value might be SNR, which can be averaged into bins and
then plotted with 'plimagefr' and the like.

Being able to also use 'pltransform' to auto-magically map azi/ele
points/lines onto the same plot would be a 'big win'; for example to plot
positions of the individual satellites at an instant in time.

> plstransform is a new addition to PLplot.  Suggestions for
> improvements to its documentation [1] are quite welcome, particularly
> if its use and purpose are unclear.
>

I'll have a look in the source to see if that helps my understanding....


Thanks,
Simon.