TESTING/EIG/sort03.f(3) Library Functions Manual TESTING/EIG/sort03.f(3) NAME TESTING/EIG/sort03.f SYNOPSIS Functions/Subroutines subroutine sort03 (rc, mu, mv, n, k, u, ldu, v, ldv, work, lwork, result, info) SORT03 Function/Subroutine Documentation subroutine sort03 (character*( * ) rc, integer mu, integer mv, integer n, integer k, real, dimension( ldu, * ) u, integer ldu, real, dimension( ldv, * ) v, integer ldv, real, dimension( * ) work, integer lwork, real result, integer info) SORT03 Purpose: SORT03 compares two orthogonal 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 S is +-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. Parameters 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 SORT03 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 SORT03 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 SORT03 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 REAL 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 REAL 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 REAL 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. RESULT RESULT is REAL 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 Author Univ. of Tennessee Univ. of California Berkeley Univ. of Colorado Denver NAG Ltd. Definition at line 154 of file sort03.f. Author Generated automatically by Doxygen for LAPACK from the source code. LAPACK Version 3.12.0 TESTING/EIG/sort03.f(3)