;+ ;PROCEDURE: rerange ; ;PURPOSE: Reformats arrays so they may be plotted as ; lattitude and longitude. Changes arrays so ; that they are in the intervals [-pi/2, +pi/2] ; and [-pi, +pi]. Can change both lattitude and ; longitude or just longitude. ; ;ARGUMENTS: lng The longitude array in radians. ; lat The corresponding lattitude array in ; radians. (Optional) ;KEYWORDS: degrees Set this to return the arrays in degrees. ; ;Created by: J.Rauchleiba 12/20/96 ;- pro rerange, lng, lat, degrees=deg if keyword_set(lat) then begin if n_elements(lng) NE n_elements(lat) then $ message, 'LNG and LAT arrays must be equal length.' lat = lat MOD (2*!pi) under = where(lat LT -!pi/2, count) if count GT 0 then begin lat(under) = -lat(under) - !pi lng(under) = lng(under) - !pi endif over = where(lat GT !pi/2, count) if count GT 0 then begin lat(over) = -lat(over) + !pi lng(over) = lng(over) - !pi endif endif lng = lng MOD (2*!pi) under = where(lng LT -!pi, count) if count GT 0 then lng(under) = lng(under) + 2*!pi over = where(lng GT !pi, count) if count GT 0 then lng(over) = lng(over) - 2*!pi if keyword_set(deg) then begin if keyword_set(lat) then lat = lat*!radeg lng = lng*!radeg endif return end