Help with code to convert latitude longitude coordonates to cartesian and then back again

jserafy — Wed, 18 Sep 2024 17:25:58 GMT

Hi:

I've read it is improper to average a series of latitude-longitude coordinates without first converting to Cartesian coordinates.

If someone could provide sas code to process the example data below, I'd appreciate it.

-----------------

data a; input location lat lon;
cards;
1 27.7970 -93.6191
2 28.0290 -93.6310
3 28.3661 -91.1429
;

*Code to convert above spherical coordinates to Cartesian coordinates;

proc print; var location cart_lat cart_lon; run;

* Code to convert the Cartesian coordinates back to spherical coordinates;
proc print; var location lat lon; run;

Re: Help with code to convert latitude longitude coordonates to cartesian and then back again

ballardw — Wed, 18 Sep 2024 17:41:44 GMT

Purpose?

How large of a geographic region are you dealing with? For most purposes if the area is less than several hundred square miles or kilometers the lat/long behave like Cartesian coordinates for most purposes.

topic Re: Help with code to convert latitude longitude coordonates to cartesian and then back again in SAS Programming

Help with code to convert latitude longitude coordonates to cartesian and then back again

Re: Help with code to convert latitude longitude coordonates to cartesian and then back again