1CURVP2(3NCARG) NCAR GRAPHICS CURVP2(3NCARG)
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6 CURVP2 - interpolate a periodic function at a specified point
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9 FUNCTION CURVP2 (T, N, X, Y, P, YP, SIGMA)
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11 This function interpolates a value at a specified point using a spline
12 under tension. CURVP1 must be called prior to calling CURVP2, and the
13 values thus obtained used as input to CURVP2. CURVP2 returns the inter‐
14 polated function value at the X-coordinate specified.
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17 T (real, input) The abscissa for which an interpolated func‐
18 tion value is desired.
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20 N (integer, input) The number of input data values. (N > 1)
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22 X (real, input) An array containing the abscissae for the
23 input function.
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25 Y (real, input) An array containing the functional values of
26 the input data -- Y(K) is the functional value at X(K) for
27 K=1,N.
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29 X (real, input) The period of the function.
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31 YP (real, input) Contains values for the second derivative (as
32 calculated by CURV1).
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34 SIGMA (real, input) Tension factor. Values near zero result in a
35 cubic spline; large values (e.g. 50) result in nearly a
36 polygonal line. A typical value is 1.
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39 CURVP2 returns the interpolated value at the specified point T.
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42 To use CURVP2, load the NCAR Graphics library ngmath.
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45 curvp1, fitgrid_params.
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47 Complete documentation for Fitgrid is available at URL
48 http://ngwww.ucar.edu/ngdoc/ng/ngmath/fitgrid/fithome.html
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51 Copyright (C) 2000
52 University Corporation for Atmospheric Research
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54 This documentation is free software; you can redistribute it and/or
55 modify it under the terms of the GNU General Public License as pub‐
56 lished by the Free Software Foundation; either version 2 of the
57 License, or (at your option) any later version.
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59 This software is distributed in the hope that it will be useful, but
60 WITHOUT ANY WARRANTY; without even the implied warranty of MER‐
61 CHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the GNU General
62 Public License for more details.
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64 You should have received a copy of the GNU General Public License along
65 with this software; if not, write to the Free Software Foundation,
66 Inc., 59 Temple Place, Suite 330, Boston, MA 02111-1307 USA.
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71UNIX March 1998 CURVP2(3NCARG)