comp.lang.idl-pvwave archive: archive » Re: Cylindrical map projection screwed up?

Home » Public Forums » archive » Re: Cylindrical map projection screwed up?

Show: Today's Messages :: Show Polls :: Message Navigator
E-mail to friend

Re: Cylindrical map projection screwed up? [message #13519 is a reply to message #13518]

Fri, 13 November 1998 00:00

Jonathan Joseph
Messages: 69
Registered: September 1998

Member

Hmmm.

It looks like this could be it. I had switched from a different
type of map projection and didn't look closely at those
numbers. I had been setting them to be the middle of the
range of latitude/longitude that I was looking at. However,
I'm not sure I understand what meaning they could have in
a cylindrical projection.

Thanks.

-Jonathan

Liam Gumley wrote:
>
> Jonathan Joseph wrote:
>> I've been doing some stuff using cylindrical map
>> projections using set_map. So, darn it, I expect
>> my lines of longitude to be vertical, and my lines
>> of latitude to be horizontal in the image.
>>
>> But, when I set the LIMIT keyword to just look
>> at a small portion of the globe, this is not
>> the case. In fact, I only get a true cylidrical
>> projection if the min and max latitude have the
>> same magnitude, ie. -30 to 30 degrees.
>
> Try this:
>
> map_set, 30, -80, limit=[20,-100,40,-60], $
> /cyl, /isot, /cont, /grid ; Bad result
>
> map_set, 0, -80, limit=[20,-100,40,-60], $
> /cyl, /isot, /cont, /grid ; Good result
>
> Cheers,
> Liam.
>
> ---
> Liam E. Gumley
> Space Science and Engineering Center, UW-Madison
> 1225 W. Dayton St., Madison WI 53706, USA
> Phone (608) 265-5358, Fax (608) 262-5974
> http://cimss.ssec.wisc.edu/~gumley

Report message to a moderator

[Message index]

		Re: Cylindrical map projection screwed up? By: Jonathan Joseph on Fri, 13 November 1998 00:00
		Re: Cylindrical map projection screwed up? By: Jonathan Joseph on Fri, 13 November 1998 00:00
		Re: Cylindrical map projection screwed up? By: Liam Gumley on Fri, 13 November 1998 00:00
		Re: Cylindrical map projection screwed up? By: davidf on Fri, 13 November 1998 00:00

Previous Topic:	OpenGL accelerated + IDL + Linux = possible?
Next Topic:	Re: Speaking of loops

-=] Back to Top [=-

[ Syndicate this forum (XML) ] [

] [

]

Current Time: Wed Oct 08 18:41:28 PDT 2025

Total time taken to generate the page: 0.00378 seconds