The file, WDBI.dx, used by that macro has the coordinates as provided in
the original World Data Bank I file.  The coordinates are raw lat-lon,
cylindrical equidistant, with lon as degrees east (-180 to 180).  A simple
transformation such as Mark/Compute/Unmark or Transform will only partially
work.  The problem is lines that cross a nominal Int'l Date Line.  That
transformation will force the "pen" to scrawl across the page.  You would
have to check for these particular lines after the transformation and
repair them.

If you want to see ASCII, you can Import and then Export in an ASCII flavor
.dx file.

The package of projections I put together some many years ago is geared
around data in [lat degrees north, lon degrees east, +/- 180].  This was
fine for my own needs at that time.  Since there was not much user interest
then, there wasn't much motivation to make them more general-purpose.  You
would have to modify the map file or use a different one and/or modify your
data.  Some of the projections may have to be changed because of the
different coordinates.  At least with everything as macros, you can see how
the projections work and modify them.



"Sharon Cady" <[EMAIL PROTECTED]>@opendx.watson.ibm.com on
02/12/2001 02:58:07 PM

Please respond to [email protected]

Sent by:  [EMAIL PROTECTED]


To:   [email protected]
cc:
Subject:  [opendx-users] World Map coordinate system



I'm almost embarrassed to ask, since I'm obviously missing something
(probably
simple), but how do I shift the coordinate system of the cylindrical
equidistant (rectangular) global map so that it goes not from -180 to -180
degrees longitude but instead ranges 0-360 ?

There are inputs into WorldMapProjections which ask for centroid of the
projections and also the range, but manipulation of these don't change the
positions of the points in the map, just the view of what is plotted (it
seems). I've tried shifting the positions myself (mark/compute); however,
with
my new map ranging 0-360 longitude, I can only see the 0-180 part (the
180-360
is ignored, apparently). Is there something somewhere which limits the view
of
this plotted object ? I looked in the wdbi.dx file to see if I could find
anything, but I didn't really see much in there, except binary data.

I can get a map to plot which "looks" like how I want it, but of course the
positions are incorrect, since they are forced to range -180 - 180. My data
won't overplot on this, unless I juggle that all around too.



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