[geos-devel] Dimension and Coordinate Sequences

[Frank Warmerdam]

strk wrote:
> On Mon, May 17, 2010 at 11:25:56AM -0400, Frank Warmerdam wrote:
>> Folks,
>>
>> I am creating a GEOS Point from 2D WKB input, then fetching back the
>> CoordinateSequence and interogating it's dimension.  I get "3".
>>
>> Looking through the code there does not seem to be a real effort to preserve
>> dimension for coordinate sequences, at least with the 
>> CoordinateArraySequence
>> implementation.  Is this intentional?
> 
> The interface was added to later make a real effort,
> but none is made at this time indeed.

Strk,

Is this a good time for me to take a crack at implementing dimension
support?   I see the dimension potentially makes it as far as the
CoordinateArraySequenceFactory, but that CoordinateArraySequence has
nothing to keep track of it.  I could add it as a private member and
ensure it is passed in by the factory.

> When non-empty you could check for IsNan(Z) but when empty you can't tell..

I'm using the C API.  Is there a nice portable way to check for NaN in C code?

Best regards,
-- 
---------------------------------------+--------------------------------------
I set the clouds in motion - turn up   | Frank Warmerdam, warmerdam at pobox.com
light and sound - activate the windows | http://pobox.com/~warmerdam
and watch the world go round - Rush    | Geospatial Programmer for Rent