Automatic Solution and Log Linearisation of DSGE Models

Code to analytically log linearise DSGE models in Matlab. Requires the symbolic toolbox.

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PURPOSE: Performs log-linearisation.
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SYNTAX: result = LogLin( VarEndoNames, VarExoNames, Parameters, Equations, SolveMode, EvalMode, EvalString, Digits );
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EXAMPLE: result = LogLin( { 'R', 'A' }, { 'EPSILON' }, { 'beta', 'rho' }, { 'beta * R * A / A(+1) = 1', 'A = A(-1) ^ rho * exp( EPSILON )' }, 2, 2 );
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OUTPUT: result: a cell array of log-linearised equations, with __d appended to variable names that are deviations from steady state.
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INPUT: VarEndoNames: a cell array of endogenous variable names
% VarExoNames: a cell array of exogenous variable names
% Parameters: a cell array of parameter names
% Equations: a cell array of equations, in Dynare notation
% SolveMode: specifies how the steady state is found
% SolveMode = 0 ---> the steady state is not found, instead __s is appended to the variable names
% SolveMode = 1 ---> the steady state is found analytically
% SolveMode = 2 ---> the steady state is found analytically, allowing all algebraic manipulations
% SolveMode = 3 ---> the steady state is found analytically, assuming real values
% SolveMode = 4 ---> the steady state is found numerically
% EvalMode: specifies any processing of the found equations
% EvalMode = 0 ---> no additional processing
% EvalMode = 1 ---> simplification
% EvalMode = 2 ---> simplification, allowing all algebraic manipulations
% EvalMode = 3 ---> numeric evaluation, to Digits precision
% EvalString: string of comma delimited equations, useful for specifying parameters or your own computed steady state values (e.g. 'beta=0.99,rho=1/2', or 'A=1')
Digits: (optional) the number of digits of accuracy for numerical compuations
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Copyright © 2011 Tom Holden ( http://www.tholden.org/ )
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