ZUNT03 compares two unitary matrices U and V to see if their


 corresponding rows or columns span the same spaces.  The rows are


 checked if RC = 'R', and the columns are checked if RC = 'C'.


 RESULT is the maximum of


    | V*V' - I | / ( MV ulp ), if RC = 'R', or


    | V'*V - I | / ( MV ulp ), if RC = 'C',


 and the maximum over rows (or columns) 1 to K of


    | U(i) - S*V(i) |/ ( N ulp )


 where abs(S) = 1 (chosen to minimize the expression), U(i) is the


 i-th row (column) of U, and V(i) is the i-th row (column) of V.

RC

          RC is CHARACTER*1


          If RC = 'R' the rows of U and V are to be compared.


          If RC = 'C' the columns of U and V are to be compared.

MU

          MU is INTEGER


          The number of rows of U if RC = 'R', and the number of


          columns if RC = 'C'.  If MU = 0 ZUNT03 does nothing.


          MU must be at least zero.

MV

          MV is INTEGER


          The number of rows of V if RC = 'R', and the number of


          columns if RC = 'C'.  If MV = 0 ZUNT03 does nothing.


          MV must be at least zero.

N

          N is INTEGER


          If RC = 'R', the number of columns in the matrices U and V,


          and if RC = 'C', the number of rows in U and V.  If N = 0


          ZUNT03 does nothing.  N must be at least zero.

K

          K is INTEGER


          The number of rows or columns of U and V to compare.


          0 <= K <= max(MU,MV).

U

          U is COMPLEX*16 array, dimension (LDU,N)


          The first matrix to compare.  If RC = 'R', U is MU by N, and


          if RC = 'C', U is N by MU.

LDU

          LDU is INTEGER


          The leading dimension of U.  If RC = 'R', LDU >= max(1,MU),


          and if RC = 'C', LDU >= max(1,N).

V

          V is COMPLEX*16 array, dimension (LDV,N)


          The second matrix to compare.  If RC = 'R', V is MV by N, and


          if RC = 'C', V is N by MV.

LDV

          LDV is INTEGER


          The leading dimension of V.  If RC = 'R', LDV >= max(1,MV),


          and if RC = 'C', LDV >= max(1,N).

WORK

          WORK is COMPLEX*16 array, dimension (LWORK)

LWORK

          LWORK is INTEGER


          The length of the array WORK.  For best performance, LWORK


          should be at least N*N if RC = 'C' or M*M if RC = 'R', but


          the tests will be done even if LWORK is 0.

RWORK

          RWORK is DOUBLE PRECISION array, dimension (max(MV,N))

RESULT

          RESULT is DOUBLE PRECISION


          The value computed by the test described above.  RESULT is


          limited to 1/ulp to avoid overflow.

INFO

          INFO is INTEGER


          0  indicates a successful exit


          -k indicates the k-th parameter had an illegal value

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Univ. of California Berkeley

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