Added new routines for computing gradients (options 13 and 15).

time-shift
Stéphane Adjemian (Charybdis) 2013-09-20 23:15:00 +02:00
parent cdc7e6b945
commit 0cdfe4d6c7
3 changed files with 151 additions and 0 deletions

View File

@ -81,6 +81,10 @@ if NumGrad
[g,badg] = numgrad3(fcn, f0, x0, epsilon, varargin{:});
case 5
[g,badg] = numgrad5(fcn, f0, x0, epsilon, varargin{:});
case 13
[g,badg] = numgrad3_(fcn, f0, x0, epsilon, varargin{:});
case 15
[g,badg] = numgrad5_(fcn, f0, x0, epsilon, varargin{:});
otherwise
error('csminwel1: Unknown method for gradient evaluation!')
end
@ -135,6 +139,10 @@ while ~done
[g1 badg1] = numgrad3(fcn, f1, x1, epsilon, varargin{:});
case 5
[g1,badg1] = numgrad5(fcn, f1, x1, epsilon, varargin{:});
case 13
[g1,badg1] = numgrad3_(fcn, f1, x1, epsilon, varargin{:});
case 15
[g1,badg1] = numgrad5_(fcn, f1, x1, epsilon, varargin{:});
otherwise
error('csminwel1: Unknown method for gradient evaluation!')
end
@ -174,6 +182,10 @@ while ~done
[g2 badg2] = numgrad3(fcn, f2, x2, epsilon, varargin{:});
case 5
[g2,badg2] = numgrad5(fcn, f2, x2, epsilon, varargin{:});
case 13
[g2,badg2] = numgrad3_(fcn, f2, x2, epsilon, varargin{:});
case 15
[g2,badg2] = numgrad5_(fcn, f2, x2, epsilon, varargin{:});
otherwise
error('csminwel1: Unknown method for gradient evaluation!')
end
@ -214,6 +226,10 @@ while ~done
[g3 badg3] = numgrad3(fcn, f3, x3, epsilon, varargin{:});
case 5
[g3,badg3] = numgrad5(fcn, f3, x3, epsilon, varargin{:});
case 13
[g3,badg3] = numgrad3_(fcn, f3, x3, epsilon, varargin{:});
case 15
[g3,badg3] = numgrad5_(fcn, f3, x3, epsilon, varargin{:});
otherwise
error('csminwel1: Unknown method for gradient evaluation!')
end
@ -283,6 +299,10 @@ while ~done
[gh,badgh] = numgrad3(fcn, fh, xh, epsilon, varargin{:});
case 5
[gh,badgh] = numgrad5(fcn, fh, xh, epsilon, varargin{:});
case 13
[gh,badgh] = numgrad3_(fcn, fh, xh, epsilon, varargin{:});
case 15
[gh,badgh] = numgrad5_(fcn, fh, xh, epsilon, varargin{:});
otherwise
error('csminwel1: Unknown method for gradient evaluation!')
end

67
matlab/numgrad3_.m Normal file
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@ -0,0 +1,67 @@
function [g, badg, f0, f1, f2] = numgrad3_(fcn,f0,x,epsilon,varargin)
% Computes the gradient of the objective function fcn using a three points
% formula if possible.
%
% Adapted from Sims' numgrad routine.
%
% See section 25.3.4 in Abramovitz and Stegun (1972, Tenth Printing, December) Handbook of Mathematical Functions.
% http://www.math.sfu.ca/~cbm/aands/
% Original file downloaded from:
% http://sims.princeton.edu/yftp/optimize/mfiles/numgrad.m
% Copyright (C) 1993-2007 Christopher Sims
% Copyright (C) 2008-2012 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.
%
% You should have received a copy of the GNU General Public License
% along with Dynare. If not, see <http://www.gnu.org/licenses/>.
delta = epsilon;
n = length(x);
g = zeros(n,1);
badg = 0;
scale = []; % one(n,1);
for i=1:n
xiold = x(i);
h = step_length_correction(xiold,scale,i)*delta;
x(i) = xiold + h;
[f1,junk1,junk2,cost_flag1] = feval(fcn, x, varargin{:});
if ~cost_flag1
fprintf('Gradient w.r.t. parameter number %3d (x=%16.8f,+h=%16.8f,f0=%16.8f,f1=%16.8f,f2=%16.8f,g0=%16.8f): penalty on the right!\n',i,xiold,h,f0,f1,f2,(f1 - f2) / (2*h))
end
x(i) = xiold - h;
[f2,junk2,junk2,cost_flag2] = feval(fcn, x, varargin{:});
if ~cost_flag2
fprintf('Gradient w.r.t. parameter number %3d (x=%16.8f,+h=%16.8f,f0=%16.8f,f1=%16.8f,f2=%16.8f,g0=%16.8f): penalty on the left!\n',i,xiold,h,f0,f1,f2,(f1 - f2) / (2*h))
end
if f0<f1 && f0<f2
fprintf('Gradient w.r.t. parameter number %3d (x=%16.8f,h=%16.8f,f0=%16.8f,f1=%16.8f,f2=%16.8f,g0=%16.8f)\n',i,xiold,h,f0,f1,f2,(f1 - f2) / (2*h))
g0 = 0;
else
g0 = (f1 - f2) / (2*h);
end
if abs(g0)< 1e15
g(i) = g0;
else
disp('Bad gradient -----------------------------------')
fprintf('Gradient w.r.t. parameter number %3d (x=%16.8f,h=%16.8f,g0=%16.8f)\n',i,xiold,h,g0)
g(i) = 0;
badg = 1;
end
x(i) = xiold;
end

64
matlab/numgrad5_.m Normal file
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@ -0,0 +1,64 @@
function [g, badg, f0, f1, f2, f3, f4] = numgrad5(fcn,f0,x,epsilon,varargin)
% Computes the gradient of the objective function fcn using a five points
% formula if possible.
%
% Adapted from Sims' numgrad.m routine.
%
% See section 25.3.6 Abramovitz and Stegun (1972, Tenth Printing, December) Handbook of Mathematical Functions.
% http://www.math.sfu.ca/~cbm/aands/
%
% TODO Try Four points formula when cost_flag3=0 or cost_flag4=0.
% Original file downloaded from:
% http://sims.princeton.edu/yftp/optimize/mfiles/numgrad.m
% Copyright (C) 1993-2007 Christopher Sims
% Copyright (C) 2008-2012 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.
%
% You should have received a copy of the GNU General Public License
% along with Dynare. If not, see <http://www.gnu.org/licenses/>.
delta = epsilon;
n = length(x);
g = zeros(n,1);
badg = 0;
scale = []; % ones(n,1);
for i=1:n
xiold = x(i);
h = step_length_correction(xiold,scale,i)*delta;
x(i) = xiold+h;
[f1,junk1,junk2,cost_flag1] = feval(fcn, x, varargin{:});
x(i) = xiold-h;
[f2,junk1,junk2,cost_flag2] = feval(fcn, x, varargin{:});
x(i) = xiold+2*h;
[f3,junk1,junk2,cost_flag3] = feval(fcn, x, varargin{:});
x(i) = xiold-2*h;
[f4,junk1,junk2,cost_flag4] = feval(fcn, x, varargin{:});
if f0<f1 && f1<f3 && f0<f2 && f2<f4
g0 = 0;
else
g0 = (8*(f1 - f2)+ f4-f3) / (12*h);
end
if abs(g0)< 1e15
g(i) = g0;
else
disp('Bad gradient -----------------------------------')
fprintf('Gradient w.r.t. parameter number %3d (x=%16.8f,h=%16.8f,g0=%16.8f)\n',i,xiold,h,g0)
g(i) = 0;
badg = 1;
end
end