redhat man page for zlassq

ZLASSQ(l)								 )								 ZLASSQ(l)

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

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

	   INTEGER	  INCX, N

	   DOUBLE	  PRECISION SCALE, SUMSQ

	   COMPLEX*16	  X( * )

PURPOSE
       ZLASSQ returns the values scl and ssq such that ( scl**2 )*ssq = x( 1 )**2 +...+ x( n )**2 + ( scale**2 )*sumsq, 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 respectively.  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) COMPLEX*16 array, dimension (N)
	       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) DOUBLE PRECISION
	       On entry, the value  scale  in the equation above.  On exit, SCALE is overwritten with the value  scl .

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

LAPACK version 3.0						   15 June 2000 							 ZLASSQ(l)