Skip site navigation (1)Skip section navigation (2)

FreeBSD Manual Pages

  
 
  

home | help 
elpa_solve_tridiagonal(3)  Library Functions Manual  elpa_solve_tridiagonal(3)

NAME
       elpa_solve_tridiagonal -	computes the eigenvalue	problem	for real
       symmetric tridiagonal matrix

SYNOPSIS
   FORTRAN INTERFACE
       use elpa
       class(elpa_t), pointer :: elpa

       call elpa%eigenvectors (d, e, q,	error)

       With the	definitions of the input and output variables:

       class(elpa_t) ::	elpa  !	returns	an instance of the ELPA	object

       datatype	:: d
	      The  diagonal  elements  of  a matrix whose dimensions have been
	      defined in elpa_setup(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)".

       datatype	:: e
	      The  offdiagonal	elements  of  the  matrix. The datatype	of the
	      diagonal	elements  can  either  be   "real(kind=c_double)"   or
	      "real(kind=c_float)".   datatype	:: q The storage space for the
	      computed eigenvectors. The datatype of the matrix	can be	either
	      "real(kind=c_double)" or "real(kind=c_float)".

       integer,	optional :: error
	      The  return error	code of	the function. Should be	"ELPA_OK". The
	      error code can be	querried with the function elpa_strerr(3)

   C INTERFACE
       #include	<elpa/elpa.h>
       elpa_t handle;

       void elpa_eigenvalues(elpa_t handle, datatype *d, datatype *e, datatype
       *q, int *error);

       With the	definitions of the input and output variables:

       elpa_t handle;
	      The handle to the	ELPA object

       datatype	*d;
	      The diagonal elements of	the  matrix.  The  dimensions  of  the
	      matrix  must  be	set  BEFORE  with  elpa_setup(3). On exist the
	      eigenvalues are stored in	d. The datatype	can be one of "double"
	      or "float".

       datatype	*e;
	      The offdiagonal elements of the matrix. The datatype can be  one
	      of "double" or "float".

       datatype	*q;
	      The  storage space for the computed eigenvectors.	The dimensions
	      of the matrix must be set	BEFORE with  the  methods  elpa_set(3)
	      and elpa_setup(3). The datatype can be one of "double", "float",
	      "double complex",	or "float complex".

       int *error;
	      The  error  code of the function.	Should be "ELPA_OK". The error
	      codes can	be querried with elpa_strerr(3)

DESCRIPTION
       Computes	 the  eigenvalue  problem  of  a  real	symmtric   tridiagonal
       matrix.The  functions  elpa_init(3), elpa_allocate(3), elpa_set(3), and
       elpa_setup(3) must  be  called  BEFORE  elpa_solve_tridiagonal  can  be
       called.

SEE ALSO
       elpa2_print_kernels(1)	 elpa_init(3)	elpa_allocate(3)   elpa_set(3)
       elpa_setup(3)   elpa_strerr(3)	elpa_eigenvalues(3)   elpa_cholesky(3)
       elpa_invert_triangular(3)   elpa_hermitian_multiply(3)	elpa_uninit(3)
       elpa_deallocate(3)

ELPA				Sat Jul	15 2017	     elpa_solve_tridiagonal(3)

Want to link to this manual page? Use this URL:
<https://man.freebsd.org/cgi/man.cgi?query=elpa_solve_tridiagonal&sektion=3&manpath=FreeBSD+Ports+14.3.quarterly>

home | help