Source code for sfepy.applications.evp_solver_app

Eigenvalue problem solver application.
from __future__ import absolute_import
import os

import numpy as nm

from sfepy.base.base import Struct, output, get_default
from sfepy.base.timing import Timer
from sfepy.applications import PDESolverApp
from sfepy.solvers import Solver
from sfepy.discrete.fem.meshio import convert_complex_output
from six.moves import range

[docs]class EVPSolverApp(PDESolverApp): """ Solve an eigenvalue problem. """
[docs] @staticmethod def process_options(options): """ Application options setup. Sets default values for missing non-compulsory options. """ get = options.get n_eigs = get('n_eigs', 5) eigs_only = get('eigs_only', False) return Struct(evps=get('evps', None, 'missing "evps" in options!'), n_eigs=n_eigs, eigs_only=eigs_only)
def __init__(self, conf, options, output_prefix, **kwargs): PDESolverApp.__init__(self, conf, options, output_prefix, init_equations=False)
[docs] def setup_options(self): PDESolverApp.setup_options(self) opts = EVPSolverApp.process_options(self.conf.options) self.app_options += opts
[docs] def setup_output(self): """ Setup various file names for the output directory given by `self.problem.output_dir`. """ output_dir = self.problem.output_dir opts = self.app_options opts.output_dir = output_dir self.mesh_results_name = self.problem.get_output_name() self.eig_results_name = os.path.join(opts.output_dir, self.problem.ofn_trunk + '_eigs.txt')
[docs] def call(self, status=None): # This cannot be in __init__(), as parametric calls may change # the output directory. self.setup_output() evp = self.solve_eigen_problem() if status is not None: n_eigs = get_default(self.app_options.n_eigs, evp.vecs.shape[0]) status.nls_status = Struct(conditions=n_eigs - len(evp.eigs)) if self.post_process_hook_final is not None: # User postprocessing. self.post_process_hook_final(self.problem, evp=evp) return evp.pb, evp
[docs] def solve_eigen_problem(self): opts = self.app_options pb = self.problem pb.set_equations(pb.conf.equations) pb.time_update() output('assembling lhs...') timer = Timer(start=True) mtx_a = pb.evaluate(pb.conf.equations['lhs'], mode='weak', auto_init=True, dw_mode='matrix') output('...done in %.2f s' % timer.stop()) if 'rhs' in pb.conf.equations: output('assembling rhs...') timer.start() mtx_b = pb.evaluate(pb.conf.equations['rhs'], mode='weak', dw_mode='matrix') output('...done in %.2f s' % timer.stop()) else: mtx_b = None _n_eigs = get_default(opts.n_eigs, mtx_a.shape[0]) output('solving eigenvalue problem for {} values...'.format(_n_eigs)) eig = Solver.any_from_conf(pb.get_solver_conf(opts.evps)) if opts.eigs_only: eigs = eig(mtx_a, mtx_b, opts.n_eigs, eigenvectors=False) svecs = None else: eigs, svecs = eig(mtx_a, mtx_b, opts.n_eigs, eigenvectors=True) output('...done') vecs = self.make_full(svecs) self.save_results(eigs, vecs) return Struct(pb=pb, eigs=eigs, vecs=vecs)
[docs] def make_full(self, svecs): if svecs is None: return None variables = self.problem.get_variables() vecs = nm.empty((variables.di.ptr[-1], svecs.shape[1]), dtype=svecs.dtype) for ii in range(svecs.shape[1]): vecs[:,ii] = variables.make_full_vec(svecs[:,ii]) return vecs
[docs] def save_results(self, eigs, vecs, out=None, mesh_results_name=None, eig_results_name=None): if vecs is not None: mesh_results_name = get_default(mesh_results_name, self.mesh_results_name) pb = self.problem pp_name = pb.conf.options.get('post_process_hook') pp = getattr(pb.conf.funmod, pp_name if pp_name is not None else '', lambda out, *args, **kwargs: out) out = get_default(out, {}) state = pb.create_state() for ii in range(eigs.shape[0]): state.set_full(vecs[:, ii]) aux = state.create_output_dict() aux2 = {} pp(aux2, pb, state) aux.update(convert_complex_output(aux2)) out.update({key + '%03d' % ii : aux[key] for key in aux}) if aux.get('__mesh__') is not None: out['__mesh__'] = aux['__mesh__'] pb.save_state(mesh_results_name, out=out) output('solution saved to %s' % mesh_results_name) eig_results_name = get_default(eig_results_name, self.eig_results_name) with open(eig_results_name, 'wb') as fd: if nm.iscomplexobj(eigs): nm.savetxt(fd, eigs, '% .18e % .18e') else: nm.savetxt(fd, eigs, '% .18e') output('eigenvalues saved to %s' % eig_results_name)