dynare/matlab/perfect-foresight-models/solve_stacked_linear_problem.m

71 lines
2.9 KiB
Matlab

function [endogenousvariables, info] = solve_stacked_linear_problem(endogenousvariables, exogenousvariables, steadystate_y, steadystate_x, M, options)
% Copyright © 2015-2022 Dynare Team
%
% This file is part of Dynare.
%
% Dynare is free software: you can redistribute it and/or modify
% it under the terms of the GNU General Public License as published by
% the Free Software Foundation, either version 3 of the License, or
% (at your option) any later version.
%
% Dynare is distributed in the hope that it will be useful,
% but WITHOUT ANY WARRANTY; without even the implied warranty of
% MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the
% GNU General Public License for more details.
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% You should have received a copy of the GNU General Public License
% along with Dynare. If not, see <https://www.gnu.org/licenses/>.
[options, y0, yT, z, i_cols, i_cols_J1, i_cols_T, i_cols_j, i_cols_1, i_cols_0, i_cols_J0, dynamicmodel] = ...
initialize_stacked_problem(endogenousvariables, options, M, steadystate_y);
ip = find(M.lead_lag_incidence(1,:)');
ic = find(M.lead_lag_incidence(2,:)');
in = find(M.lead_lag_incidence(3,:)');
% Evaluate the Jacobian of the dynamic model at the deterministic steady state.
[d1,jacobian] = dynamicmodel(steadystate_y([ip; ic; in]), transpose(steadystate_x), M.params, steadystate_y, 1);
% Check that the dynamic model was evaluated at the steady state.
if max(abs(d1))>1e-12
error('Jacobian is not evaluated at the steady state!')
end
nyp = nnz(M.lead_lag_incidence(1,:));
ny0 = nnz(M.lead_lag_incidence(2,:));
nyf = nnz(M.lead_lag_incidence(3,:));
nd = nyp+ny0+nyf; % size of y (first argument passed to the dynamic file).
jexog = transpose(nd+(1:M.exo_nbr));
jendo = transpose(1:nd);
z = bsxfun(@minus, z, steadystate_y);
x = bsxfun(@minus, exogenousvariables, steadystate_x');
[y, check, ~, ~, errorcode] = dynare_solve(@linear_perfect_foresight_problem, z(:), ...
options.simul.maxit, options.dynatol.f, options.dynatol.x, ...
options, ...
jacobian, y0-steadystate_y, yT-steadystate_y, ...
x, M.params, steadystate_y, ...
M.maximum_lag, options.periods, M.endo_nbr, i_cols, ...
i_cols_J1, i_cols_1, i_cols_T, i_cols_j, i_cols_0, i_cols_J0, ...
jendo, jexog);
if all(imag(y)<.1*options.dynatol.x)
if ~isreal(y)
y = real(y);
end
else
check = 1;
end
endogenousvariables = [y0 bsxfun(@plus,reshape(y,M.endo_nbr,options.periods), steadystate_y) yT];
if check
info.status = false;
if options.debug
dprintf('solve_stacked_linear_problem: Nonlinear solver routine failed with errorcode=%i.', errorcode)
end
else
info.status = true;
end