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NAME
     classq - return the values scl and ssq such that   (  scl**2
     )*ssq = x( 1 )**2 +...+ x( n )**2 + ( scale**2 )*sumsq,

SYNOPSIS
     SUBROUTINE CLASSQ( N, X, INCX, SCALE, SUMSQ )

     INTEGER INCX, N

     REAL SCALE, SUMSQ

     COMPLEX X( * )



     #include <sunperf.h>

     void classq(int n, complex x, int incx, float *sscale, float
               *sumsq) ;

PURPOSE
     CLASSQ returns the values scl and ssq such that

     where x( i ) = abs( X( 1 + ( i - 1 )*INCX ) ). The value  of
     sumsq  is  assumed to be at least unity and the value of ssq
     will then satisfy

        1.0 .le. ssq .le. ( sumsq + 2*n ).

     scale is assumed to be  non-negative  and  scl  returns  the
     value

        scl = max( scale, abs( real( x( i ) ) ), abs( aimag( x( i
     ) ) ) ),
               i

     scale and sumsq must be supplied in SCALE and SUMSQ  respec-
     tively.   SCALE  and  SUMSQ  are  overwritten by scl and ssq
     respectively.

     The routine makes only one pass through the vector X.


ARGUMENTS
     N         (input) INTEGER
               The number of elements to be used from the  vector
               X.

     X         (input) REAL
               The vector x as described above.  x( i )  = X( 1 +
               ( i - 1 )*INCX ), 1 <= i <= n.

     INCX      (input) INTEGER
               The increment between  successive  values  of  the
               vector X.  INCX > 0.

     SCALE     (input/output) REAL
               On entry, the value  scale  in the equation above.
               On  exit, SCALE is overwritten with the value  scl
               .

     SUMSQ     (input/output) REAL
               On entry, the value  sumsq  in the equation above.
               On  exit, SUMSQ is overwritten with the value  ssq
               .

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