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

FreeBSD Manual Pages

  
 
  

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

NAME
       elpa_eigenvalues_float -	computes the eigenvalues of a real single-
       precision symmetric matrix

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

       call elpa%eigenvalues_float (a, ev, error)

       With the	definitions of the input and output variables:

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

       datatype	:: a
	      The  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 datatype of the matrix must
	      be real(kind=c_float). The matrix	has to be  symmetric  this  is
	      not  checked  by	the routine. In	case of	a GPU build a can be a
	      device pointer of	type "type(c_ptr) to a matrix a	on the	device
	      memory.

       datatype	:: ev
	      The  vector ev where the eigenvalues will	be stored in ascending
	      order.   The   datatype	of   the    vector    ev    must    be
	      "real(kind=c_float)".  In	case of	a GPU build ev can be a	device
	      pointer of type "type(c_ptr) to the vector of eigenvalues	in the
	      device memory

       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_float(elpa_t  handle, datatype *a, datatype *ev,
       int *error);

       With the	definitions of the input and output variables:

       elpa_t handle;
	      The handle to the	ELPA object

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

       datatype	*ev;
	      The storage for the computed eigenvalues.	 Eigenvalues  will  be
	      stored  in ascendig order. The datatype must be "float". In case
	      of a GPU build ev	can be a device	 pointer  to  the  vectors  of
	      eigenvalues in the device	memory.

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

DESCRIPTION
       Compute the eigenvalues of a single 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 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_deallocate(3)

ELPA				Wed Sep	1 2021	     elpa_eigenvalues_float(3)

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

home | help