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102	<div class="routine_details" id="_LL_NARCS_DISTANCES">
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104	<h2><a class="top" href="#container">top</a>LL_NARCS_DISTANCES </h2>
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106	<p class="header">
107	<span class="result">result = </span>LL_NARCS_DISTANCES(<span class="result"><a href="#_LL_NARCS_DISTANCES_param_lon0">lon0</a>, <a href="#_LL_NARCS_DISTANCES_param_lat0">lat0</a>, <a href="#_LL_NARCS_DISTANCES_param_arc_dist">arc_dist</a>, <a href="#_LL_NARCS_DISTANCES_param_az">az</a></span>, <a href="#_LL_NARCS_DISTANCES_keyword_DEGREES">DEGREES</a>=<span class="result">DEGREES</span>)</p>
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110	NAME:
111	LL_NARCS_DISTANCES
112
113	PURPOSE:
114	This function returns the longitude and latitude [lon, lat] of
115	a point a given arc distance (-pi <= Arc_Dist <= pi), and azimuth (Az),
116	from a specified location Lon0, lat0.
117	Same as LL_ARC_DISTANCE but for n points without do loop.
118
119	CATEGORY:
120	Mapping, geography.
121
122	CALLING SEQUENCE:
123	Result = LL_NARCS_DISTANCES(Lon, lat0, Arc_Dist, Az)
124
125	INPUTS:
126	Lon0: An array containing the longitude of the starting point.
127	Values are assumed to be in radians unless the keyword
128	DEGREES is set.
129	Lat0: An array containing the latitude of the starting point.
130	Values are assumed to be in radians unless the keyword
131	DEGREES is set.
132	Arc_Dist: The arc distance from Lon_lat0. The value must be between
133	-!PI and +!PI. To express distances in arc units, divide
134	by the radius of the globe expressed in the original units.
135	For example, if the radius of the earth is 6371 km, divide
136	the distance in km by 6371 to obtain the arc distance.
137	Az: The azimuth from Lon_lat0. The value is assumed to be in
138	radians unless the keyword DEGREES is set.
139
140	KEYWORD PARAMETERS:
141	DEGREES: Set this keyword to express all measurements and
142	results in degrees.
143
144	OUTPUTS:
145	This function returns a (2, n) array containing the
146	longitude / latitude of the resultings points. Values are in radians
147	unless the keyword DEGREES is set.
148
149	PROCEDURE:
150	Formula from Map Projections - a working manual. USGS paper
151	1395. Equations (5-5) and (5-6).
152
153	EXAMPLE:
154	Lon_lat0 = [1.0, 2.0] ; Initial point specified in radians
155	Arc_Dist = 2.0 ; Arc distance in radians
156	Az = 1.0 ; Azimuth in radians
157	Result = LL_ARC_DISTANCE(Lon_lat0, Arc_Dist, Az)
158	PRINT, Result
159	2.91415 -0.622234
160
161	IDL> lon0 = [-10, 20, 100]
162	IDL> lat0 = [0, -10, 45]
163	IDL> lon1 = [10, 60, 280]
164	IDL> lat1 = [0, 10, 45]
165	IDL> dist = map_npoints(lon0, lat0, lon1, lat1, azimuth = azi, /two_by_two)
166	IDL> earthradius = 6378206.4d0
167	IDL> res = ll_narcs_distances(lon0, lat0, dist/earthradius, azi, /degrees)
168	IDL> print, reform(res[0, *])
169	10.000000 60.000000 280.00000
170	IDL> print, reform(res[1, *])
171	1.1999280e-15 10.000000 45.000000
172
173	MODIFICATION HISTORY:
174	Based on the IDL function ll_arc_distance.pro,v 1.11 2003/02/03</div>
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179	<h3>Parameters</h3>
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182	<h4 id="_LL_NARCS_DISTANCES_param_lon0">lon0
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195	<h4 id="_LL_NARCS_DISTANCES_param_lat0">lat0
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208	<h4 id="_LL_NARCS_DISTANCES_param_arc_dist">arc_dist
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221	<h4 id="_LL_NARCS_DISTANCES_param_az">az
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239	<h3>Keywords</h3>
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241	<h4 id="_LL_NARCS_DISTANCES_keyword_DEGREES">DEGREES
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