1c_csa1s(3NCARG) NCAR GRAPHICS c_csa1s(3NCARG)
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6 c_csa1s - cubic spline approximation, simple entry for one-dimensional
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10 float *c_csa1s(int, float [], float [], int, int, float [], int *);
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14 float *c_csa1s(int n, float xi[], float yi[], int knots,
15 int m, float xo[], int *ier);
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19 n (integer,input) The number of input data points. It must be
20 that n is greater than 3 and, depending on the size of
21 knots below, n may have to be larger.
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23 xi (real, input) An array dimensioned for n containing the
24 abscissae for the input function.
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26 yi (real, input) An array dimensioned for n containing the
27 functional values of the input function -- yi[k] is the
28 functional value at xi[k] for k=0,n-1.
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30 knots (integer, input) The number of knots to be used in con‐
31 structing the approximation spline. knots must be at least
32 4. The larger the value for knots, the closer the approxi‐
33 mated curve will come to passing through the input function
34 values.
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36 m (integer, input) The number of values to be calculated for
37 the output curve.
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39 xo (real, input) An array dimensioned for m containing the X
40 coordinates of the output curve.
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42 ier (pointer to integer, output) An error return value. If *ier
43 is returned as 0, then no errors were detected. If *ier is
44 non-zero, then refer to the error list in the error table
45 for details.
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48 c_csa1s is called to find an approximating cubic spline for one-dimen‐
49 sional input data. If you want to weight the input data values, calcu‐
50 late derivatives, or handle data sparse areas specially, then you will
51 need to use c_csa1xs.
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53 c_csa1s returns a pointer to a linear array of data that is the approx‐
54 imated curve.
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57 To use c_csa1s, load the NCAR Graphics library ngmath.
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60 csagrid, c_csa1xs, c_csa1ls, c_csa1lxs
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62 Complete documentation for Csagrid is available at URL
63 http://ngwww.ucar.edu/ngdoc/ng/ngmath/csagrid/csahome.html
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66 Copyright (C) 2000
67 University Corporation for Atmospheric Research
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69 This documentation is free software; you can redistribute it and/or
70 modify it under the terms of the GNU General Public License as pub‐
71 lished by the Free Software Foundation; either version 2 of the
72 License, or (at your option) any later version.
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74 This software is distributed in the hope that it will be useful, but
75 WITHOUT ANY WARRANTY; without even the implied warranty of MER‐
76 CHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the GNU General
77 Public License for more details.
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79 You should have received a copy of the GNU General Public License along
80 with this software; if not, write to the Free Software Foundation,
81 Inc., 59 Temple Place, Suite 330, Boston, MA 02111-1307 USA.
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86UNIX January 1999 c_csa1s(3NCARG)