Re: How do I get at the values on an axis?

[Glenn Carver <Glenn.Carver@xxxxxxxxxxxxxxxx>]

At 6:20 pm +0000 26/11/99, Mark A. Verschell wrote:
>Try referring to theta as the axis it is on (e.g., z if it is replacing
>depth),
>for example:
>
>let newt=h*z

Thanks Mark.

That's kindof what I was trying. I was trying to access theta or 'z' as
ferret would call it on the 'grid' that ferret seems to use for the data
that's read in (something like GL18). But that got me nowhere, but then I
don't understand how the 'GL' grids work.

Following your note, I got the following to work:

define grid/z=pv ng
let theta=z[g=ng]

Which feels rather clumsy since I have to use a variable 'pv' in the file
to get at the independent coordinate. I don't quite understand why ferret
won't let me use 'theta' directly but hides it. Since theta is being used
as a z coordinate, it could be viewed as a variable with itself as it's
grid. Hmmm.. I suppose the problem would be if the user changed theta it
could cause confusion for variables with theta in their grid. The answer to
that could be to produce an invariant axis 'z' equivalent to theta and a
variable 'theta' with 'z' as it's grid?  Ah well, it works, what the hell.

   Glenn


----
Dr. Glenn Carver, Senior Research Associate,
Centre for Atmospheric Science, Chemistry Dept., Cambridge University, UK
mailto:Glenn.Carver@atm.ch.cam.ac.uk   http://www.atm.ch.cam.ac.uk/~glenn/

              "I never think of the future, it comes soon enough"
                   - Albert Einstein