47 lines
1.5 KiB
Matlab
47 lines
1.5 KiB
Matlab
function d=jacob_element(func,element,args)
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% function d=jacob_element(func,element,args)
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% returns an entry of the finite differences approximation to the jacobian of func
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%
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% INPUTS
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% func [function name] string with name of the function
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% element [int] the index showing the element within the jacobian that should be returned
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% args [cell array] arguments provided to func
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%
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% OUTPUTS
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% d [double] jacobian[element]
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%
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% SPECIAL REQUIREMENTS
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% none
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% Copyright (C) 2010-2011 Dynare Team
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%
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% This file is part of Dynare.
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%
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% Dynare is free software: you can redistribute it and/or modify
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% it under the terms of the GNU General Public License as published by
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% the Free Software Foundation, either version 3 of the License, or
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% (at your option) any later version.
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%
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% Dynare is distributed in the hope that it will be useful,
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% but WITHOUT ANY WARRANTY; without even the implied warranty of
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% MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the
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% GNU General Public License for more details.
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%
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% You should have received a copy of the GNU General Public License
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% along with Dynare. If not, see <http://www.gnu.org/licenses/>.
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func = str2func(func);
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h=10e-6;
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pargs=args;
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margs=args;
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% length(args) is used instead of size(args, 2) to avoid to transpose column vectors
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for i=1:length(args)
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if i==element
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pargs{i} = pargs{i} + h;
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margs{i} = margs{i} - h;
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end
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end
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d=(func(pargs{:})...
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-func(margs{:}))/(2*h);
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