Changeset 125 for trunk/SRC/Interpolation/ll_narcs_distances.pro

Timestamp:

07/06/06 16:10:25 (18 years ago)

Author:

pinsard

Message:

improvements of Interpolation/*.pro header

File:

• trunk/SRC/Interpolation/ll_narcs_distances.pro (modified) (5 diffs)

trunk/SRC/Interpolation/ll_narcs_distances.pro

@@ -3 +3 @@
 ; @file_comments
 ; This function returns the longitude and latitude [lon, lat] of
-;a point a given arc distance (-pi <= Arc_Dist <= pi), and azimuth (Az),
-;from a specified location Lon0, lat0.
-;       Same as LL_ARC_DISTANCE but for n points without do loop.
+; a point a given arc distance (-pi <= Arc_Dist <= pi), and azimuth (Az),
+; from a specified location Lon0, lat0.
+; Same as LL_ARC_DISTANCE but for n points without do loop.
+;
+; Formula from Map Projections - a working manual.  USGS paper
+; 1395.  Equations (5-5) and (5-6).
 ;
 ; @categories Mapping, geography
 ;
-;    @param Lon0 {in}{required}  An array containing the longitude of the starting point.
-;             Values are assumed to be in radians unless the keyword
-;             DEGREES is set.
-;    @param Lat0 {in}{required}  An array containing the latitude of the starting point.
-;             Values are assumed to be in radians unless the keyword
-;             DEGREES is set.
-;    @param Arc_Dist {in}{required}  The arc distance from Lon_lat0. The value must be between
+; @param Lon0 {in}{required}
+; An array containing the longitude of the starting point.
+; Values are assumed to be in radians unless the keyword DEGREES is set.
+;
+; @param Lat0 {in}{required}
+; An array containing the latitude of the starting point.
+; Values are assumed to be in radians unless the keyword DEGREES is set.
+;
+; @param Arc_Dist {in}{required}
+; The arc distance from Lon_lat0. The value must be between
 ; -!PI and +!PI. To express distances in arc units, divide
 ;  by the radius of the globe expressed in the original units.
 ;  For example, if the radius of the earth is 6371 km, divide
-;  the distance in km by 6371 to obtain the arc distance.    
-;    @param Az {in}{required}   The azimuth from Lon_lat0. The value is assumed to be in
-;  radians unless the keyword DEGREES is set.
+;  the distance in km by 6371 to obtain the arc distance.
 ;
-; @keyword    DEGREES  Set this keyword to express all measurements and
-;  results in degrees.
+; @param Az {in}{required}
+; The azimuth from Lon_lat0. The value is assumed to be in
+; radians unless the keyword DEGREES is set.
+;
+; @keyword DEGREES
+; Set this keyword to express all measurements and results in degrees.
 ;
 ; @returns
-; a (2, n) array containing the 
-;       longitude / latitude of the resultings points. Values are in radians
-;       unless the keyword DEGREES is set.
+; a (2, n) array containing the longitude/latitude of the resultings points.
+; Values are in radians unless the keyword DEGREES is set.
 ;
-; @file_comments
-;Formula from Map Projections - a working manual.  USGS paper
-;1395.  Equations (5-5) and (5-6).
-;
-; @examples 
+; @examples
 ; IDL> Lon_lat0 = [1.0, 2.0]; Initial point specified in radians
 ; IDL> Arc_Dist = 2.0; Arc distance in radians
@@ -43 +46 @@
 ;       2.91415    -0.622234
 ;
-;IDL> lon0 = [-10, 20, 100]
-;IDL> lat0 = [0, -10, 45]
-;IDL> lon1 = [10, 60, 280]
-;IDL> lat1 = [0, 10, 45]
-;IDL> dist = map_npoints(lon0, lat0, lon1, lat1, azimuth = azi, /two_by_two)
-;IDL> earthradius = 6378206.4d0
-;IDL> res = ll_narcs_distances(lon0, lat0, dist/earthradius, azi, /degrees)
-;IDL> print, reform(res[0, *])
+; IDL> lon0 = [-10, 20, 100]
+; IDL> lat0 = [0, -10, 45]
+; IDL> lon1 = [10, 60, 280]
+; IDL> lat1 = [0, 10, 45]
+; IDL> dist = map_npoints(lon0, lat0, lon1, lat1, azimuth = azi, /two_by_two)
+; IDL> earthradius = 6378206.4d0
+; IDL> res = ll_narcs_distances(lon0, lat0, dist/earthradius, azi, /degrees)
+; IDL> print, reform(res[0, *])
 ;       10.000000       60.000000       280.00000
-;IDL> print, reform(res[1, *])
-;          1.1999280e-15       10.000000       45.000000
+; IDL> print, reform(res[1, *])
+;           1.1999280e-15       10.000000       45.000000
 ;
 ; @history
@@ -62 +65 @@
 ; @version $Id$
 ;
-;-
-
-;+
-; @file_comments Return the [lon, lat] of the point a given arc distance 
-;(-pi <= arc_dist <= pi),
-; and azimuth (az), from lon_lat0.
 ;-
 ;
@@ -94 +91 @@
 
   zero = where(arc_dist eq 0, count)
-  IF count NE 0 THEN BEGIN 
+  IF count NE 0 THEN BEGIN
     lam[zero] = lon0[zero]
     phi[zero] = lat0[zero]
-  ENDIF 
+  ENDIF
 
   if keyword_set(degs) then return, transpose([[lam], [phi]]) / s $
@@ -103 +100 @@
 
 end
-
-