* ..
* .. Local Scalars ..
DOUBLE PRECISION W, XABS, YABS, Z
+ LOGICAL X_IS_NAN, Y_IS_NAN
+* ..
+* .. External Functions ..
+ LOGICAL DISNAN
+ EXTERNAL DISNAN
* ..
* .. 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
- DLAPY2 = W
- ELSE
- DLAPY2 = W*SQRT( ONE+( Z / W )**2 )
+ X_IS_NAN = DISNAN( X )
+ Y_IS_NAN = DISNAN( Y )
+ IF ( X_IS_NAN ) DLAPY2 = X
+ IF ( Y_IS_NAN ) DLAPY2 = Y
+*
+ IF ( .NOT.( X_IS_NAN.OR.Y_IS_NAN ) ) THEN
+ XABS = ABS( X )
+ YABS = ABS( Y )
+ W = MAX( XABS, YABS )
+ Z = MIN( XABS, YABS )
+ IF( Z.EQ.ZERO ) THEN
+ DLAPY2 = W
+ ELSE
+ DLAPY2 = W*SQRT( ONE+( Z / W )**2 )
+ END IF
END IF
RETURN
*
* ..
* .. Local Scalars ..
REAL W, XABS, YABS, Z
+ LOGICAL X_IS_NAN, Y_IS_NAN
+* ..
+* .. External Functions ..
+ LOGICAL SISNAN
+ EXTERNAL SISNAN
* ..
* .. 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 )
+* ..
+* .. Executable Statements ..
+*
+ X_IS_NAN = SISNAN( X )
+ Y_IS_NAN = SISNAN( Y )
+ IF ( X_IS_NAN ) SLAPY2 = X
+ IF ( Y_IS_NAN ) SLAPY2 = Y
+*
+ IF ( .NOT.( X_IS_NAN.OR.Y_IS_NAN ) ) THEN
+ 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
END IF
RETURN
*