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classq.f(3)			    LAPACK			   classq.f(3)

NAME
       classq.f -

SYNOPSIS
   Functions/Subroutines
       subroutine classq (N, X, INCX, SCALE, SUMSQ)
	   CLASSQ updates a sum of squares represented in scaled form.

Function/Subroutine Documentation
   subroutine classq (integerN, complex, dimension( * )X, integerINCX,
       realSCALE, realSUMSQ)
       CLASSQ updates a sum of squares represented in scaled form.

       Purpose:

	    CLASSQ 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.

       Parameters:
	   N

		     N is INTEGER
		     The number of elements to be used from the vector X.

	   X

		     X is COMPLEX array, dimension (N)
		     The vector x as described above.
			x( i )	= X( 1 + ( i - 1 )*INCX ), 1 <= i <= n.

	   INCX

		     INCX is INTEGER
		     The increment between successive values of the vector X.
		     INCX > 0.

	   SCALE

		     SCALE is REAL
		     On entry, the value  scale	 in the equation above.
		     On exit, SCALE is overwritten with the value  scl .

	   SUMSQ

		     SUMSQ is REAL
		     On entry, the value  sumsq	 in the equation above.
		     On exit, SUMSQ is overwritten with the value  ssq .

       Author:
	   Univ. of Tennessee

	   Univ. of California Berkeley

	   Univ. of Colorado Denver

	   NAG Ltd.

       Date:
	   September 2012

       Definition at line 107 of file classq.f.

Author
       Generated automatically by Doxygen for LAPACK from the source code.

Version 3.4.2			Sat Nov 16 2013			   classq.f(3)
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