1CLAQR1(1)           LAPACK auxiliary routine (version 3.2)           CLAQR1(1)
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NAME

SYNOPSIS

7       SUBROUTINE CLAQR1( N, H, LDH, S1, S2, V )
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9           COMPLEX        S1, S2
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11           INTEGER        LDH, N
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13           COMPLEX        H( LDH, * ), V( * )
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15           COMPLEX        ZERO
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17           PARAMETER      ( ZERO = ( 0.0e0, 0.0e0 ) )
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19           REAL           RZERO
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21           PARAMETER      ( RZERO = 0.0e0 )
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23           COMPLEX        CDUM, H21S, H31S
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25           REAL           S
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27           INTRINSIC      ABS, AIMAG, REAL
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29           REAL           CABS1
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31           CABS1(         CDUM ) = ABS( REAL( CDUM ) ) + ABS( AIMAG( CDUM ) )
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33           IF(            N.EQ.2 ) THEN
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35           S              = CABS1( H( 1, 1 )-S2 ) + CABS1( H( 2, 1 ) )
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37           IF(            S.EQ.RZERO ) THEN
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39           V(             1 ) = ZERO
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41           V(             2 ) = ZERO
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43           ELSE
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45           H21S           = H( 2, 1 ) / S
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47           V(             1 ) = H21S*H( 1, 2 ) + ( H( 1, 1 )-S1 )* ( ( H( 1, 1
48                          )-S2 ) / S )
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50           V(             2 ) = H21S*( H( 1, 1 )+H( 2, 2 )-S1-S2 )
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52           END            IF
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54           ELSE
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56           S              = CABS1( H( 1, 1 )-S2 ) + CABS1(  H(  2,  1  )  )  +
57                          CABS1( H( 3, 1 ) )
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59           IF(            S.EQ.ZERO ) THEN
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61           V(             1 ) = ZERO
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63           V(             2 ) = ZERO
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65           V(             3 ) = ZERO
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67           ELSE
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69           H21S           = H( 2, 1 ) / S
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71           H31S           = H( 3, 1 ) / S
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73           V(             1 ) = ( H( 1, 1 )-S1 )*( ( H( 1, 1 )-S2 ) / S ) + H(
74                          1, 2 )*H21S + H( 1, 3 )*H31S
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76           V(             2 ) = H21S*( H( 1, 1 )+H( 2, 2 )-S1-S2 ) + H(  2,  3
77                          )*H31S
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79           V(             3  )  = H31S*( H( 1, 1 )+H( 3, 3 )-S1-S2 ) + H21S*H(
80                          3, 2 )
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82           END            IF
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84           END            IF
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86           END
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PURPOSE

89 LAPACK auxiliary routine (versionNo3v.e2m)ber 2008                       CLAQR1(1)