1 LOGICAL FUNCTION SLCTES( ZR, ZI, D )
2 *
3 * -- LAPACK test routine (version 3.1) --
4 * Univ. of Tennessee, Univ. of California Berkeley and NAG Ltd..
5 * November 2006
6 *
7 * .. Scalar Arguments ..
8 REAL D, ZI, ZR
9 * ..
10 *
11 * Purpose
12 * =======
13 *
14 * SLCTES returns .TRUE. if the eigenvalue (ZR/D) + sqrt(-1)*(ZI/D)
15 * is to be selected (specifically, in this subroutine, if the real
16 * part of the eigenvalue is negative), and otherwise it returns
17 * .FALSE..
18 *
19 * It is used by the test routine SDRGES to test whether the driver
20 * routine SGGES succesfully sorts eigenvalues.
21 *
22 * Arguments
23 * =========
24 *
25 * ZR (input) REAL
26 * The numerator of the real part of a complex eigenvalue
27 * (ZR/D) + i*(ZI/D).
28 *
29 * ZI (input) REAL
30 * The numerator of the imaginary part of a complex eigenvalue
31 * (ZR/D) + i*(ZI).
32 *
33 * D (input) REAL
34 * The denominator part of a complex eigenvalue
35 * (ZR/D) + i*(ZI/D).
36 *
37 * =====================================================================
38 *
39 * .. Parameters ..
40 REAL ZERO, ONE
41 PARAMETER ( ZERO = 0.0E+0, ONE = 1.0E+0 )
42 * ..
43 * .. Intrinsic Functions ..
44 INTRINSIC SIGN
45 * ..
46 * .. Executable Statements ..
47 *
48 IF( D.EQ.ZERO ) THEN
49 SLCTES = ( ZR.LT.ZERO )
50 ELSE
51 SLCTES = ( SIGN( ONE, ZR ).NE.SIGN( ONE, D ) )
52 END IF
53 *
54 RETURN
55 *
56 * End of SLCTES
57 *
58 END
2 *
3 * -- LAPACK test routine (version 3.1) --
4 * Univ. of Tennessee, Univ. of California Berkeley and NAG Ltd..
5 * November 2006
6 *
7 * .. Scalar Arguments ..
8 REAL D, ZI, ZR
9 * ..
10 *
11 * Purpose
12 * =======
13 *
14 * SLCTES returns .TRUE. if the eigenvalue (ZR/D) + sqrt(-1)*(ZI/D)
15 * is to be selected (specifically, in this subroutine, if the real
16 * part of the eigenvalue is negative), and otherwise it returns
17 * .FALSE..
18 *
19 * It is used by the test routine SDRGES to test whether the driver
20 * routine SGGES succesfully sorts eigenvalues.
21 *
22 * Arguments
23 * =========
24 *
25 * ZR (input) REAL
26 * The numerator of the real part of a complex eigenvalue
27 * (ZR/D) + i*(ZI/D).
28 *
29 * ZI (input) REAL
30 * The numerator of the imaginary part of a complex eigenvalue
31 * (ZR/D) + i*(ZI).
32 *
33 * D (input) REAL
34 * The denominator part of a complex eigenvalue
35 * (ZR/D) + i*(ZI/D).
36 *
37 * =====================================================================
38 *
39 * .. Parameters ..
40 REAL ZERO, ONE
41 PARAMETER ( ZERO = 0.0E+0, ONE = 1.0E+0 )
42 * ..
43 * .. Intrinsic Functions ..
44 INTRINSIC SIGN
45 * ..
46 * .. Executable Statements ..
47 *
48 IF( D.EQ.ZERO ) THEN
49 SLCTES = ( ZR.LT.ZERO )
50 ELSE
51 SLCTES = ( SIGN( ONE, ZR ).NE.SIGN( ONE, D ) )
52 END IF
53 *
54 RETURN
55 *
56 * End of SLCTES
57 *
58 END