1CLARGV(1)           LAPACK auxiliary routine (version 3.1)           CLARGV(1)
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NAME

6       CLARGV  - a vector of complex plane rotations with real cosines, deter‐
7       mined by elements of the complex vectors x and y
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SYNOPSIS

10       SUBROUTINE CLARGV( N, X, INCX, Y, INCY, C, INCC )
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12           INTEGER        INCC, INCX, INCY, N
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14           REAL           C( * )
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16           COMPLEX        X( * ), Y( * )
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PURPOSE

19       CLARGV generates a vector of complex plane rotations with real cosines,
20       determined  by  elements  of  the  complex  vectors  x  and y.  For i =
21       1,2,...,n
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23          (        c(i)   s(i) ) ( x(i) ) = ( r(i) )
24          ( -conjg(s(i))  c(i) ) ( y(i) ) = (   0  )
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26          where c(i)**2 + ABS(s(i))**2 = 1
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28       The following conventions are used (these are the same  as  in  CLARTG,
29       but differ from the BLAS1 routine CROTG):
30          If y(i)=0, then c(i)=1 and s(i)=0.
31          If x(i)=0, then c(i)=0 and s(i) is chosen so that r(i) is real.
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ARGUMENTS

35       N       (input) INTEGER
36               The number of plane rotations to be generated.
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38       X       (input/output) COMPLEX array, dimension (1+(N-1)*INCX)
39               On  entry, the vector x.  On exit, x(i) is overwritten by r(i),
40               for i = 1,...,n.
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42       INCX    (input) INTEGER
43               The increment between elements of X. INCX > 0.
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45       Y       (input/output) COMPLEX array, dimension (1+(N-1)*INCY)
46               On entry, the vector y.  On exit, the sines of the plane  rota‐
47               tions.
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49       INCY    (input) INTEGER
50               The increment between elements of Y. INCY > 0.
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52       C       (output) REAL array, dimension (1+(N-1)*INCC)
53               The cosines of the plane rotations.
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55       INCC    (input) INTEGER
56               The increment between elements of C. INCC > 0.
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FURTHER DETAILS

59       6-6-96 - Modified with a new algorithm by W. Kahan and J. Demmel
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61       This  version  has  a  few  statements  commented out for thread safety
62       (machine parameters are computed on each entry). 10 feb 03, SJH.
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67 LAPACK auxiliary routine (versionNo3v.e1m)ber 2006                       CLARGV(1)
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