ncl_csstri man page
CSSTRI — calculates a Delaunay triangulation for data on a sphere
CALL CSSTRI (N, RLAT, RLON, NT, NTRI, IWK, RWK, IER)
(integer,input) The number of input data points (N > 2).
(real, input) An array containing the latitudes of the input data, expressed in degrees. The first three points must not be collinear (lie on a common great circle).
(real, input) An array containing the longitudes of the input data, expressed in degrees.
(integer, output) The number of triangles in the triangulation, unless IER .NE. 0, in which case NT = 0. Where NB is the number of boundary points on the convex hull of the data, if NB .GE. 3, then NT = 2N-NB-2, otherwise NT=2N-4. The input data are considered to be bounded if they all lie in one hemisphere. Dimensioning NT for 2*N will always work.
(integer, output) A two-dimensional integer array dimensioned for 3 x NT where NT is the number of triangles in the triangulation (NT is at most 2*N). NTRI contains the triangulation data. The vertices of the Kth triangle are: (PLAT(NTRI((1,K)),PLON(NTRI(1,K)), (PLAT(NTRI((2,K)),PLON(NTRI(2,K)), (PLAT(NTRI((3,K)),PLON(NTRI(3,K))
(integer, input) An integer workspace of length 27*N.
(double precision, input) A work array dimensioned for 13*N. Note that this work array must be typed DOUBLE PRECISION.
(integer, output) An error return value. If IER is returned as 0, then no errors were detected. If IER is non-zero, then refer to the man page for cssgrid_errors for details.
CSSTRI is called to find a Delaunay triangulation of data randomly positioned on the surface of a sphere.
To use CSSTRI, load the NCAR Graphics library ngmath.
css_overview, cssgrid, csvoro.
Complete documentation for Cssgrid is available at URL
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University Corporation for Atmospheric Research
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