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c Scilab ( http://www.scilab.org/ ) - This file is part of Scilab
c Copyright (C) INRIA
c
c This file must be used under the terms of the CeCILL.
c This source file is licensed as described in the file COPYING, which
c you should have received as part of this distribution. The terms
c are also available at
c http://www.cecill.info/licences/Licence_CeCILL_V2.1-en.txt
subroutine calcsc(type)
c this routine calculates scalar quantities used to
c compute the next k polynomial and new estimates of
c the quadratic coefficients.
c type - integer variable set here indicating how the
c calculations are normalized to avoid overflow
common /gloglo/ p, qp, k, qk, svk, sr, si, u,
* v, a, b, c, d, a1, a2, a3, a6, a7, e, f, g,
* h, szr, szi, lzr, lzi, eta, are, mre, n, nn
double precision p(101), qp(101), k(101),
* qk(101), svk(101), sr, si, u, v, a, b, c, d,
* a1, a2, a3, a6, a7, e, f, g, h, szr, szi,
* lzr, lzi
real eta, are, mre
integer n, nn
integer type
c synthetic division of k by the quadratic 1,u,v
call quadsd(n, u, v, k(1), qk(1), c, d)
if (abs(c).gt.abs(k(n))*100.*eta) go to 10
if (abs(d).gt.abs(k(n-1))*100.*eta) go to 10
type = 3
c type=3 indicates the quadratic is almost a factor
c of k
return
10 if (abs(d).lt.abs(c)) go to 20
type = 2
c type=2 indicates that all formulas are divided by d
e = a/d
f = c/d
g = u*b
h = v*b
a3 = (a+g)*e + h*(b/d)
a1 = b*f - a
a7 = (f+u)*a +h
return
20 type = 1
c type=1 indicates that all formulas are divided by c
e = a/c
f = d/c
g = u*e
h = v*b
a3 = a*e + (h/c+g)*b
a1 = b - a*(d/c)
a7 = a + g*d + h*f
return
end
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