zhbtrd zhetrd zhptrd zpteqr zstedc zstein zstemr zsteqr zungtr zunmtr zupgtr zupmtr

zupmtr() void zupmtr ( char  side, char  uplo, char  trans, int  m, int  n, doublecomplex  ap[], doublecomplex  tau[], int  ldc, doublecomplex  c[], doublecomplex  work[], int *  info  ) Multiplies by a transform matrix from a complex Hermitian matrix in packed form to tridiagonal form Purpose This routine overwrites the general real m x n matrix C with side = 'L' side = 'R' trans = 'N': Q * C C * Q trans = 'T': 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 zhptrd: If uplo = 'U', Q = H(nq-1) . . . H(2) H(1). If uplo = 'L', Q = H(1) H(2) . . . H(nq-1). Parameters [in] side = 'L': Apply Q or Q^H from the Left. = 'R': Apply Q or Q^H from the Right. [in] uplo = 'U': Upper triangular packed storage used in previous call to zhptrd. = 'L': Lower triangular packed storage used in previous call to zhptrd. [in] trans = 'N': No transpose, apply Q. = 'T': Transpose, apply Q^H. [in] m Number of rows of the matrix C. (m >= 0) (If m = 0, returns without computation) [in] n Number of columns of the matrix C. (n >= 0) (If n = 0, returns without computation) [in] ap[] Array ap[lap] (lap >= m(m + 1)/2 if side = 'L', lap >= n(n + 1)/2 if side = 'R') The vectors which define the elementary reflectors, as returned by zhptrd. ap[] is modified by the routine but restored on exit. [in] tau[] Array tau[ltau] (ltau >= m - 1 if side = 'L', ltau >= n - 1 if side = 'R') tau[i] must contain the scalar factor of the elementary reflector H(i), as returned by zhptrd. [in] ldc Leading dimension of the two dimensional array c[][]. (ldc >= max(1, m)) [in,out] c[][] Array c[lc][ldc] (lc >= n) [in] The m x n matrix C. [out] C is overwritten by Q*C or Q^H*C or C*Q^H or C*Q. [out] work[] Array work[lwork] (lwork >= n if side = 'L', lwork >= m if side = 'R') Work array. [out] info = 0: Successful exit. = -1: The argument side had an illegal value. (side != 'L' nor 'R') = -2: The argument uplo had an illegal value. (uplo != 'U' nor 'L') = -3: The argument trans had an illegal value. (trans != 'N' nor 'T') = -4: The argument m had an illegal value. (m < 0) = -5: The argument n had an illegal value. (n < 0) = -8: The argument ldc had an illegal value. (ldc < max(1, m)) Reference LAPACK