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REAL FUNCTION SLAPY2( X, Y )
*
* -- LAPACK auxiliary routine (version 3.0) --
* Univ. of Tennessee, Univ. of California Berkeley, NAG Ltd.,
* Courant Institute, Argonne National Lab, and Rice University
* October 31, 1992
*
* .. Scalar Arguments ..
REAL X, Y
* ..
*
* Purpose
* =======
*
* SLAPY2 returns sqrt(x**2+y**2), taking care not to cause unnecessary
* overflow.
*
* Arguments
* =========
*
* X (input) REAL
* Y (input) REAL
* X and Y specify the values x and y.
*
* =====================================================================
*
* .. Parameters ..
REAL ZERO
PARAMETER ( ZERO = 0.0E0 )
REAL ONE
PARAMETER ( ONE = 1.0E0 )
* ..
* .. Local Scalars ..
REAL W, XABS, YABS, Z
* ..
* .. Intrinsic Functions ..
INTRINSIC ABS, MAX, MIN, SQRT
* ..
* .. Executable Statements ..
*
XABS = ABS( X )
YABS = ABS( Y )
W = MAX( XABS, YABS )
Z = MIN( XABS, YABS )
IF( Z.EQ.ZERO ) THEN
SLAPY2 = W
ELSE
SLAPY2 = W*SQRT( ONE+( Z / W )**2 )
END IF
RETURN
*
* End of SLAPY2
*
END
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