elpa_solve_tridiagonal.3 2.91 KB
 Andreas Marek committed Jul 15, 2017 1 2 3 4 5 6 7 8 9 10 11 12 13 14 15 16 17 18 19 20 21 22 23 24 25 26 27 28 29 30 31 32 33 34 35 36 37 38 39 40 41 42 43 44 45 46 47 48 49 50 51 52 53 54 55 56 57 58 59 60 61 62 63 64 65 66 67 68 69 70 71 ``````.TH "elpa_solve_tridiagonal" 3 "Sat Jul 15 2017" "ELPA" \" -*- nroff -*- .ad l .nh .SH NAME elpa_solve_tridiagonal \- computes the eigenvalue problem for real symmetric tridiagonal matrix .br .SH SYNOPSIS .br .SS FORTRAN INTERFACE use elpa .br class(elpa_t), pointer :: elpa .br .RI "call elpa%\fBeigenvectors\fP (d, e, q, error)" .br .RI " " .br .RI "With the definitions of the input and output variables:" .br .RI "class(elpa_t) :: \fBelpa\fP ! returns an instance of the ELPA object" .br .TP .RI "datatype :: \fBd\fP" The diagonal elements of a matrix whose dimensions have been defined in \fBelpa_setup\fP(3). On exist the eigenvalues are stored in this 1d-array. The datatype of the diagonal elements can either be "real(kind=c_double)" or "real(kind=c_float)". .TP .RI "datatype :: \fBe\fP" The offdiagonal elements of the matrix. The datatype of the diagonal elements can either be "real(kind=c_double)" or "real(kind=c_float)". .RI "datatype :: \fBq\fP" The storage space for the computed eigenvectors. The datatype of the matrix can be either "real(kind=c_double)" or "real(kind=c_float)". .TP .RI "integer, optional :: \fBerror\fP" The return error code of the function. Should be "ELPA_OK". The error code can be querried with the function \fBelpa_strerr\fP(3) .br .SS C INTERFACE #include .br elpa_t handle; .br .RI "void \fBelpa_eigenvalues\fP(\fBelpa_t\fP handle, \fBdatatype\fP *d, \fBdatatype\fP *e, \fBdatatype\fP *q, \fBint\fP *error);" .br .RI " " .br .RI "With the definitions of the input and output variables:" .br .TP .RI "elpa_t \fBhandle\fP;" The handle to the ELPA object .TP .RI "datatype *\fBd\fP;" The diagonal elements of the matrix. The dimensions of the matrix must be set \fIBEFORE\fP with \fBelpa_setup\fP(3). On exist the eigenvalues are stored in d. The \fBdatatype\fP can be one of "double" or "float". .TP .RI "datatype *\fBe\fP;" The offdiagonal elements of the matrix. The \fBdatatype\fP can be one of "double" or "float". .TP .RI "datatype *\fBq\fP;" The storage space for the computed eigenvectors. The dimensions of the matrix must be set \fIBEFORE\fP with the methods \fBelpa_set\fP(3) and \fBelpa_setup\fP(3). The \fBdatatype\fP can be one of "double", "float", "double complex", or "float complex". .TP .RI "int *\fBerror\fP;" The error code of the function. Should be "ELPA_OK". The error codes can be querried with \fBelpa_strerr\fP(3) .SH DESCRIPTION Computes the eigenvalue problem of a real symmtric tridiagonal matrix.The functions \fBelpa_init\fP(3), \fBelpa_allocate\fP(3), \fBelpa_set\fP(3), and \fBelpa_setup\fP(3) must be called \fIBEFORE\fP \fBelpa_solve_tridiagonal\fP can be called. .br .SH "SEE ALSO" .br `````` Andreas Marek committed Jul 15, 2017 72 ``\fBelpa2_print_kernels\fP(1) \fBelpa_init\fP(3) \fBelpa_allocate\fP(3) \fBelpa_set\fP(3) \fBelpa_setup\fP(3) \fBelpa_strerr\fP(3) \fBelpa_eigenvalues\fP(3) \fBelpa_cholesky\fP(3) \fBelpa_invert_triangular\fP(3) \fBelpa_hermitian_multiply\fP(3) \fBelpa_uninit\fP(3) \fBelpa_deallocate\fP(3)``