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author | Joe Hunkeler <jhunkeler@gmail.com> | 2015-08-11 16:51:37 -0400 |
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committer | Joe Hunkeler <jhunkeler@gmail.com> | 2015-08-11 16:51:37 -0400 |
commit | 40e5a5811c6ffce9b0974e93cdd927cbcf60c157 (patch) | |
tree | 4464880c571602d54f6ae114729bf62a89518057 /math/surfit/sf_b1eval.x | |
download | iraf-osx-40e5a5811c6ffce9b0974e93cdd927cbcf60c157.tar.gz |
Repatch (from linux) of OSX IRAF
Diffstat (limited to 'math/surfit/sf_b1eval.x')
-rw-r--r-- | math/surfit/sf_b1eval.x | 108 |
1 files changed, 108 insertions, 0 deletions
diff --git a/math/surfit/sf_b1eval.x b/math/surfit/sf_b1eval.x new file mode 100644 index 00000000..d07006fc --- /dev/null +++ b/math/surfit/sf_b1eval.x @@ -0,0 +1,108 @@ +# Copyright(c) 1986 Association of Universities for Research in Astronomy Inc. + +# SF_B1LEG -- Procedure to evaluate all the non-zero Legendrefunctions for +# a single point and given order. + +procedure sf_b1leg (x, order, k1, k2, basis) + +real x # array of data points +int order # order of polynomial, order = 1, constant +real k1, k2 # normalizing constants +real basis[ARB] # basis functions + +int i +real ri, xnorm + +begin + basis[1] = 1. + if (order == 1) + return + + xnorm = (x + k1) * k2 + basis[2] = xnorm + if (order == 2) + return + + do i = 3, order { + ri = i + basis[i] = ((2. * ri - 3.) * xnorm * basis[i-1] - + (ri - 2.) * basis[i-2]) / (ri - 1.) + } +end + + +# SF_B1CHEB -- Procedure to evaluate all the non zero Chebyshev function +# for a given x and order. + +procedure sf_b1cheb (x, order, k1, k2, basis) + +real x # number of data points +int order # order of polynomial, 1 is a constant +real k1, k2 # normalizing constants +real basis[ARB] # array of basis functions + +int i +real xnorm + +begin + basis[1] = 1. + if (order == 1) + return + + xnorm = (x + k1) * k2 + basis[2] = xnorm + if (order == 2) + return + + do i = 3, order + basis[i] = 2. * xnorm * basis[i-1] - basis[i-2] +end + + +# SF_B1SPLINE1 -- Evaluate all the non-zero spline1 functions for a +# single point. + +procedure sf_b1spline1 (x, npieces, k1, k2, basis, left) + +real x # set of data points +int npieces # number of polynomial pieces minus 1 +real k1, k2 # normalizing constants +real basis[ARB] # basis functions +int left # index of the appropriate spline functions + +real xnorm + +begin + xnorm = (x + k1) * k2 + left = min (int (xnorm), npieces) + + basis[2] = xnorm - left + basis[1] = 1. - basis[2] +end + + +# SF_B1SPLINE3 -- Procedure to evaluate all the non-zero basis functions +# for a cubic spline. + +procedure sf_b1spline3 (x, npieces, k1, k2, basis, left) + +real x # array of data points +int npieces # number of polynomial pieces +real k1, k2 # normalizing constants +real basis[ARB] # array of basis functions +int left # array of indices for first non-zero spline + +real sx, tx + +begin + sx = (x + k1) * k2 + left = min (int (sx), npieces) + + sx = sx - left + tx = 1. - sx + + basis[1] = tx * tx * tx + basis[2] = 1. + tx * (3. + tx * (3. - 3. * tx)) + basis[3] = 1. + sx * (3. + sx * (3. - 3. * sx)) + basis[4] = sx * sx * sx +end |