Re: contour boundaries

[Ben Tupper <btupper(at)bigelow.org>]

Funny,  I have had the same problem with the Gulf of Maine!  The GOM's
long axis runs NE-SW but the data coords are NW and EW.  It's a diamond
hole and square peg problem. My solution is to prevent the data from
being displayed by capturing it in the PATH_XY and PATH_INFO keywords.  

CONTOUR, Data, Path_XY = XY, Path_INFO = Info, /Path_Data_Coords, Levels
= [...]

Then filter the XY values by location (I don't recall what parameters I
used; might have been a straight line running along the coast.)  Use the
PLOTS command to then display the contour.   You will lose the contour
labeling when you do it this way.  You can use linestyle/color to
distinguish different contours.  

Ben 

Remy Luerssen wrote:
> 
> I am having troubles with a contouring program in IDL.  I have gridded in situ
> measurements taken from stations throughout the Gulf of Maine.  I am contouring
> the data over a map of the Gulf of Maine.  In order to take into consideration
> where the land is, the gridded in situ data was changed to NaN where there was
> land.  The problem that I am having is that the contouring program is not
> recognizing the boundaries of the dataset.  There are contouring lines going
> through the land, eventhough the data its self are NaNs.  But the kicker is
> that there is a data boundary that does not border the coast (the stations end
> but not due to land construct) that is recognized.  The contour lines stop
> like they should.  Any ideas what is going on?
> 
> I would appreciate any suggestions!
> 
> Thanks,
> 
> Remy

-- 
Ben Tupper
Bigelow Laboratory for Ocean Sciences
180 McKown Point Rd.
W. Boothbay Harbor, ME 04575
btupper@bigelow.org