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LOGICAL FUNCTION SB02MS( REIG, IEIG )
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C RELEASE 4.0, WGS COPYRIGHT 1999.
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C To select the unstable eigenvalues for solving the discrete-time
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C algebraic Riccati equation.
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C Input/Output Parameters
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C REIG (input) DOUBLE PRECISION
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C The real part of the current eigenvalue considered.
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C IEIG (input) DOUBLE PRECISION
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C The imaginary part of the current eigenvalue considered.
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C The function value SB02MS is set to .TRUE. for an unstable
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C eigenvalue (i.e., with modulus greater than or equal to one) and
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C to .FALSE., otherwise.
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C V. Sima, Katholieke Univ. Leuven, Belgium, Aug. 1997.
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C Algebraic Riccati equation, closed loop system, discrete-time
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C system, optimal regulator, Schur form.
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C ******************************************************************
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PARAMETER ( ONE = 1.0D0 )
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C .. Scalar Arguments ..
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DOUBLE PRECISION IEIG, REIG
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C .. External Functions ..
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DOUBLE PRECISION DLAPY2
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C .. Executable Statements ..
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SB02MS = DLAPY2( REIG, IEIG ).GE.ONE
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C *** Last line of SB02MS ***