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

6       ZLASSQ  - the values scl and ssq such that   ( scl**2 )*ssq = x( 1 )**2
7       +...+ x( n )**2 + ( scale**2 )*sumsq,
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SYNOPSIS

10       SUBROUTINE ZLASSQ( N, X, INCX, SCALE, SUMSQ )
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12           INTEGER        INCX, N
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14           DOUBLE         PRECISION SCALE, SUMSQ
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16           COMPLEX*16     X( * )
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PURPOSE

19       ZLASSQ returns the values scl and ssq such that
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21       where x( i ) = abs( X( 1 + ( i - 1 )*INCX ) ). The value  of  sumsq  is
22       assumed to be at least unity and the value of ssq will then satisfy
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24          1.0 .le. ssq .le. ( sumsq + 2*n ).
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26       scale is assumed to be non-negative and scl returns the value
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28          scl = max( scale, abs( real( x( i ) ) ), abs( aimag( x( i ) ) ) ),
29                 i
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31       scale  and  sumsq  must  be  supplied  in SCALE and SUMSQ respectively.
32       SCALE and SUMSQ are overwritten by scl and ssq respectively.
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34       The routine makes only one pass through the vector X.
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ARGUMENTS

38       N       (input) INTEGER
39               The number of elements to be used from the vector X.
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41       X       (input) COMPLEX*16 array, dimension (N)
42               The vector x as described above.  x( i )  = X( 1  +  (  i  -  1
43               )*INCX ), 1 <= i <= n.
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45       INCX    (input) INTEGER
46               The  increment between successive values of the vector X.  INCX
47               > 0.
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49       SCALE   (input/output) DOUBLE PRECISION
50               On entry, the value  scale  in the equation  above.   On  exit,
51               SCALE is overwritten with the value  scl .
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53       SUMSQ   (input/output) DOUBLE PRECISION
54               On  entry,  the  value  sumsq  in the equation above.  On exit,
55               SUMSQ is overwritten with the value  ssq .
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59 LAPACK auxiliary routine (versionNo3v.e1m)ber 2006                       ZLASSQ(1)