1CSA3LS(3NCARG)                   NCAR GRAPHICS                  CSA3LS(3NCARG)
2
3
4

NAME

6       CSA3LS - cubic spline approximation, simple entry for three-dimensional
7       input, list output
8

SYNOPSIS

10       CALL CSA3LS (NI, XI, UI, KNOTS, NO, XO, YO, ZO, UO,
11                    NWRK, WORK, IER)
12

DESCRIPTION

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
18       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(3,L)  is  the Z coordinate for the input domain for
22                   L=1,NI.
23
24       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
28       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
35       NO          (integer,  input)  The  number  of coordinate values in the
36                   output list.  NO can be any positive number.
37
38       XO          (real, input) An array dimensioned for NO containing the  X
39                   coordinates of the output list.
40
41       YO          (real,  input) An array dimensioned for NO containing the Y
42                   coordinates of the output list.
43
44       ZO          (real, input) An array dimensioned for NO containing the  Z
45                   coordinates of the output list.
46
47       UO          (real,  output)  An array dimensioned for NO containing the
48                   calculated function values for the output spline.  UO(I) is
49                   the  calculated functional value at (XO(I),YO(I),ZO(I)) for
50                   I=1,NO.
51
52       NWRK        (integer, input) The size of the WORK array.  NWRK must  be
53                   at  least  NK  *  (NK+3)  where  NK = KNOTS(1) * KNOTS(2) *
54                   KNOTS(3).
55
56       WORK        (real, input) A work array dimensioned for NWRK.
57
58       IER         (integer,  output)  An  error  return  value.   If  IER  is
59                   returned as 0, then no errors were detected. If IER is non-
60                   zero, then refer to the man  page  for  csagrid_errors  for
61                   details.
62

USAGE

64       CSA3LS is called to find an approximating cubic spline for three-dimen‐
65       sional input data.  If you want to weight the input data values, calcu‐
66       late  derivatives, or handle data sparse areas specially, then you will
67       need to use CSA3LXS.
68

ACCESS

70       To use CSA3LS, load the NCAR Graphics library ngmath.
71

SEE ALSO

73       csagrid, csa3s, csa3xs, csa3lxs
74
75       Complete documentation for Csagrid is available at URL
76       http://ngwww.ucar.edu/ngdoc/ng/ngmath/csagrid/csahome.html
77

79       Copyright (C) 2000
80       University Corporation for Atmospheric Research
81
82       This documentation is free software; you  can  redistribute  it  and/or
83       modify  it  under  the  terms of the GNU General Public License as pub‐
84       lished by the  Free  Software  Foundation;  either  version  2  of  the
85       License, or (at your option) any later version.
86
87       This  software  is  distributed in the hope that it will be useful, but
88       WITHOUT ANY  WARRANTY;  without  even  the  implied  warranty  of  MER‐
89       CHANTABILITY  or FITNESS FOR A PARTICULAR PURPOSE.  See the GNU General
90       Public License for more details.
91
92       You should have received a copy of the GNU General Public License along
93       with  this  software;  if  not,  write to the Free Software Foundation,
94       Inc., 59 Temple Place, Suite 330, Boston, MA 02111-1307 USA.
95
96
97
98
99UNIX                             January 1999                   CSA3LS(3NCARG)
Impressum