CUNMTR overwrites the general complex M-by-N matrix C with


                 SIDE = 'L'     SIDE = 'R'


 TRANS = 'N':      Q * C          C * Q


 TRANS = 'C':      Q**H * C       C * Q**H


 where Q is a complex unitary matrix of order nq, with nq = m if


 SIDE = 'L' and nq = n if SIDE = 'R'. Q is defined as the product of


 nq-1 elementary reflectors, as returned by CHETRD:


 if UPLO = 'U', Q = H(nq-1) . . . H(2) H(1);


 if UPLO = 'L', Q = H(1) H(2) . . . H(nq-1).

SIDE

          SIDE is CHARACTER*1


          = 'L': apply Q or Q**H from the Left;


          = 'R': apply Q or Q**H from the Right.

UPLO

          UPLO is CHARACTER*1


          = 'U': Upper triangle of A contains elementary reflectors


                 from CHETRD;


          = 'L': Lower triangle of A contains elementary reflectors


                 from CHETRD.

TRANS

          TRANS is CHARACTER*1


          = 'N':  No transpose, apply Q;


          = 'C':  Conjugate transpose, apply Q**H.

M

          M is INTEGER


          The number of rows of the matrix C. M >= 0.

N

          N is INTEGER


          The number of columns of the matrix C. N >= 0.

A

          A is COMPLEX array, dimension


                               (LDA,M) if SIDE = 'L'


                               (LDA,N) if SIDE = 'R'


          The vectors which define the elementary reflectors, as


          returned by CHETRD.

LDA

          LDA is INTEGER


          The leading dimension of the array A.


          LDA >= max(1,M) if SIDE = 'L'; LDA >= max(1,N) if SIDE = 'R'.

TAU

          TAU is COMPLEX array, dimension


                               (M-1) if SIDE = 'L'


                               (N-1) if SIDE = 'R'


          TAU(i) must contain the scalar factor of the elementary


          reflector H(i), as returned by CHETRD.

C

          C is COMPLEX array, dimension (LDC,N)


          On entry, the M-by-N matrix C.


          On exit, C is overwritten by Q*C or Q**H*C or C*Q**H or C*Q.

LDC

          LDC is INTEGER


          The leading dimension of the array C. LDC >= max(1,M).

WORK

          WORK is COMPLEX array, dimension (MAX(1,LWORK))


          On exit, if INFO = 0, WORK(1) returns the optimal LWORK.

LWORK

          LWORK is INTEGER


          The dimension of the array WORK.


          If SIDE = 'L', LWORK >= max(1,N);


          if SIDE = 'R', LWORK >= max(1,M).


          For optimum performance LWORK >= N*NB if SIDE = 'L', and


          LWORK >=M*NB if SIDE = 'R', where NB is the optimal


          blocksize.


          If LWORK = -1, then a workspace query is assumed; the routine


          only calculates the optimal size of the WORK array, returns


          this value as the first entry of the WORK array, and no error


          message related to LWORK is issued by XERBLA.

INFO

          INFO is INTEGER


          = 0:  successful exit


          < 0:  if INFO = -i, the i-th argument had an illegal value

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NAG Ltd.

December 2016