1CSA3S(3NCARG) NCAR GRAPHICS CSA3S(3NCARG)
2
6 CSA3S - cubic spline approximation, simple entry for three-dimensional
7 input
8
10 CALL CSA3S (NI, XI, UI, KNOTS, NXO, NYO, NZO, XO, YO, ZO,
11 UO, NWRK, WORK, IER)
12
14 NI (integer,input) The number of input data points. It must be
15 that NI .gt. 3 and, depending on the size of KNOTS below,
16 NI may have to be larger.
17 XI (real, input) An array containing the X - Y - Z coordinates
19 of the input data points. XI is dimensioned for 3 x NI.
20 XI(1,L) is the X coordinate, XI(2,L) is the Y coordinate,
21 and XI(2,L) is the Z coordinate for the input domain for
22 L=1,NI.
23 UI (real, input) An array dimensioned for NI containing func‐
25 tion values at the input XI values, that is, UI(L) is the
26 value of the input function at XI(L) for L=1,NI.
27 KNOTS (integer, input) An array dimensioned for 3 containing the
29 number of knots to be used in each coordinate direction for
30 constructing the approximation spline. KNOTS(I) must be at
31 least 4 for I=1,3. The larger the value for KNOTS, the
32 closer the approximated curve will come to passing through
33 the input function values.
34 NXO (integer, input) The number of X coordinate values in the
36 output grid.
37 NYO (integer, input) The number of Y coordinate values in the
39 output grid.
40 NZO (integer, input) The number of Z coordinate values in the
42 output grid.
43 XO (real, input) An array dimensioned for NXO containing the X
45 coordinates of the output surface.
46 YO (real, input) An array dimensioned for NYO containing the Y
48 coordinates of the output surface.
49 ZO (real, input) An array dimensioned for NZO containing the Y
51 coordinates of the output surface.
52 UO (real, output) An array dimensioned for NXO x NYO x NZO
54 containing the calculated function values for the output
55 function. UO(I,J,K) is the calculated functional value at
56 (XO(I), YO(J), ZO(K)) for I=1,NXO and J=1,NYO and K=1,NZO.
57 NWRK (integer, input) The size of the WORK array. NWRK must be
59 at least NK * (NK+3) where NK = KNOTS(1) * KNOTS(2) *
60 KNOTS(3).
61 WORK (real, input) A work array dimensioned for NWRK.
63 IER (integer, output) An error return value. If IER is
65 returned as 0, then no errors were detected. If IER is non-
66 zero, then refer to the man page for csagrid_errors for
67 details.
68
70 CSA3S is called to find an approximating cubic spline for three-dimen‐
71 sional input data. If you want to weight the input data values, calcu‐
72 late derivatives, or handle data sparse areas specially, then you will
73 need to use CSA3S.
74
76 To use CSA3XS, load the NCAR Graphics library ngmath.
77
79 csagrid, csa3xs, csa3ls, csa3lxs
80 Complete documentation for Csagrid is available at URL
82 http://ngwww.ucar.edu/ngdoc/ng/ngmath/csagrid/csahome.html
83
85 Copyright (C) 2000
86 University Corporation for Atmospheric Research
87 This documentation is free software; you can redistribute it and/or
89 modify it under the terms of the GNU General Public License as pub‐
90 lished by the Free Software Foundation; either version 2 of the
91 License, or (at your option) any later version.
92 This software is distributed in the hope that it will be useful, but
94 WITHOUT ANY WARRANTY; without even the implied warranty of MER‐
95 CHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the GNU General
96 Public License for more details.
97 You should have received a copy of the GNU General Public License along
99 with this software; if not, write to the Free Software Foundation,
100 Inc., 59 Temple Place, Suite 330, Boston, MA 02111-1307 USA.
101UNIX January 1999 CSA3S(3NCARG)