1CURV2(3NCARG) NCAR GRAPHICS CURV2(3NCARG)
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6 CURV2 - 1D interpolation for non-periodic functions.
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9 FUNCTION CURV2 (T, N, X, Y, YP, SIGMA)
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11 This function interpolates a value at a specified point using a spline
12 under tension. CURV1 must be called prior to calling CURV2, and the
13 values thus obtained used as input to CURV2. CURV2 returns the interpo‐
14 lated 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 YP (real, input) Contains values for the second derivative (as
30 calculated by CURV1).
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32 SIGMA (real, input) Tension factor. Values near zero result in a
33 cubic spline; large values (e.g. 50) result in nearly a
34 polygonal line. A typical value is 1.
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37 CURV2 returns the interpolated value at the specified point T.
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40 To use CURV2, load the NCAR Graphics library ngmath.
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43 curv1, fitgrid_params.
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45 Complete documentation for Fitgrid is available at URL
46 http://ngwww.ucar.edu/ngdoc/ng/ngmath/fitgrid/fithome.html
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49 Copyright (C) 2000
50 University Corporation for Atmospheric Research
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52 The use of this Software is governed by a License Agreement.
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56UNIX March 1998 CURV2(3NCARG)