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

FreeBSD Manual Pages

  
 
  

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

NAME
     elpa_eigenvalues_double - computes all eigenvalues <lambda> for a real sym-
     metric eigenproblem: A*Q = <lambda>*Q

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

     call elpa_handle%eigenvalues_double (a, ev, error)

     With the definitions of the input and output variables:

     class(elpa_t) :: elpa_handle
	    An instance of the ELPA object.

     real(kind=c_double) :: a	    OR	 type(c_ptr) :: a
	    The local part of the host/device matrix A for which the eigenvalues
	    should  be	computed.  The dimensions of matrix a must be set BEFORE
	    with the methods elpa_set(3) and elpa_setup(3).  The  global  matrix
	    has  to be symmetric, this is not checked by the routine. In case of
	    a GPU build a can be a pointer to the device memory.

     real(kind=c_double) :: ev	    OR	 type(c_ptr) :: ev
	    The global array where the eigenvalues <lambda> will  be  stored  in
	    ascending  order.  In case of a GPU build ev can be a pointer to the
	    device memory.

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

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

     void elpa_eigenvalues_double(elpa_t elpa_handle, double *a, double *ev, int
     *error);

     With the definitions of the input and output variables:

     elpa_t  elpa_handle;
	    The handle to the ELPA object

     double  *a;
	    The local part of the host/device matrix A for which the eigenvalues
	    should  be	computed.  The dimensions of matrix a must be set BEFORE
	    with the methods elpa_set(3) and elpa_setup(3). The global matrix  A
	    has  to be symmetric, this is not checked by the routine. In case of
	    a GPU build a can be a pointer to the device memory.

     datatype_real  *ev;
	    The array where the eigenvalues <lambda> will be stored in ascending
	    order. Eigenvalues will be stored in ascending order. In case  of  a
	    GPU build ev can be a pointer to the device memory.

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

DESCRIPTION
     Computes  the  eigenvalues of a double precision real symmetric matrix. The
     functions elpa_init(3), elpa_allocate(3),	elpa_set(3),  and  elpa_setup(3)
     must be called BEFORE elpa_eigenvalues_double 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_skew_eigenvalues(3)  elpa_eigenvectors(3)
     elpa_skew_eigenvectors(3)	   elpa_cholesky(3)    elpa_invert_triangular(3)
     elpa_solve_tridiagonal(3) elpa_eigenvalues(3)  elpa_uninit(3)  elpa_deallo-
     cate(3)

ELPA				 Thu Nov 28 2024      elpa_eigenvalues_double(3)

Want to link to this manual page? Use this URL:
<https://man.freebsd.org/cgi/man.cgi?query=elpa_eigenvalues_double&sektion=3&manpath=FreeBSD+Ports+15.1.quarterly>

home | help