[Spice_discussion] RE: Cookbook for CSPICE? (Matthew M. Copeland)

[Ed Wright]

On May 21, 2004, at 9:09 AM, Matthew M. Copeland wrote:

> Thanks for the pointers.  In the source directory, I found what I was
> looking for in the subpt program.  I've modified it just a little to
> accept a kernels text file that lists the files to include, but I'm
> getting an error that I can't quite figure out how to solve, and I'm
> hoping that someone might be able to give me a hand.
>
> Here is the output:
>                                                                        
>          
> --------------------------------------------------------------------
>              Welcome to SUBPT
>
> This program demonstrates the use of CSPICE in computing
> the apparent sub-observer point on a target body.   The
> computations use light time corrections.
>
> Enter the location of the kernels.txt file:
> /home/spice/kernels/kernels.txt
>
> Working ... Please wait.
>
> Enter the name for the observing body: titan
>
> Enter the name for a target body: cassini

It seems you reversed your observer and target bodies. The routine 
finds the sub-point of the observer on the target, the subpoint of 
Titan on Cassini has no meaning.

As always,
Ed Wright

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