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Fix distinction between initial values provided to dyn_ramsey_static.m and stale unchanged initial values in oo_.steady_state 

In case of no steady state file, they are identical, but with a steady state file, they are not. Moreover, this fixes a problem with the dimension of the input to the steady state file. ys was not initialized and had wrong dimensions
Also adds comments to file.
time-shift
Johannes Pfeifer 2014-10-30 11:45:08 +01:00
parent 9300a061aa
commit c2da796153
1 changed files with 16 additions and 15 deletions
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31
matlab/dyn_ramsey_static.m
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@ -1,4 +1,4 @@
function [steady_state,params,check] = dyn_ramsey_static(x,M,options_,oo)
function [steady_state,params,check] = dyn_ramsey_static(ys_init,M,options_,oo)
% function [steady_state,params,check] = dyn_ramsey_static_(x)
% Computes the static first order conditions for optimal policy
@ -39,8 +39,8 @@ options_.steadystate.nocheck = 1; %disable checking because Lagrange multipliers
nl_func = @(x) dyn_ramsey_static_1(x,M,options_,oo);
% check_static_model is a subfunction
if check_static_model(oo.steady_state,M,options_,oo) && ~options_.steadystate_flag
steady_state = oo.steady_state;
if check_static_model(ys_init,M,options_,oo) && ~options_.steadystate_flag
steady_state = ys_init;
return
elseif options_.steadystate_flag
k_inst = [];
@ -50,14 +50,14 @@ elseif options_.steadystate_flag
M.endo_names,'exact')];
end
if inst_nbr == 1
inst_val = csolve(nl_func,oo.steady_state(k_inst),'',options_.solve_tolf,100);
inst_val = csolve(nl_func,ys_init(k_inst),'',options_.solve_tolf,100); %solve for instrument, using univariate solver, starting at initial value for instrument
else
[inst_val,info1] = dynare_solve(nl_func,oo.steady_state(k_inst),0);
[inst_val,info1] = dynare_solve(nl_func,ys_init(k_inst),0); %solve for instrument, using multivariate solver, starting at initial value for instrument
end
ys(k_inst) = inst_val;
ys_init(k_inst) = inst_val;
exo_ss = [oo.exo_steady_state oo.exo_det_steady_state];
[xx,params,check] = evaluate_steady_state_file(ys,exo_ss,M,options_);
[junk,junk,steady_state] = nl_func(inst_val);
[xx,params,check] = evaluate_steady_state_file(ys_init,exo_ss,M,options_); %run steady state file again to update parameters
[junk,junk,steady_state] = nl_func(inst_val); %compute and return steady state
else
n_var = M.orig_endo_nbr;
xx = oo.steady_state(1:n_var);
@ -92,18 +92,19 @@ if options_.steadystate_flag
k_inst = [k_inst; strmatch(instruments(i,:), ...
endo_names,'exact')];
end
oo.steady_state(k_inst) = x;
[x,params,check] = evaluate_steady_state_file(oo.steady_state,...
ys_init=zeros(size(oo.steady_state)); %create starting vector for steady state computation as only instrument value is handed over
ys_init(k_inst) = x; %set instrument, the only value required for steady state computation, to current value
[x,params,check] = evaluate_steady_state_file(ys_init,... returned x now has size endo_nbr as opposed to input size of n_instruments
[oo.exo_steady_state; ...
oo.exo_det_steady_state], ...
M,options_);
end
xx = zeros(endo_nbr,1);
xx(1:M.orig_endo_nbr) = x(1:M.orig_endo_nbr); %take care of steady state file that will also return multipliers
% setting steady state of auxiliary variables
% that depends on original endogenous variables
if any([M.aux_vars.type] ~= 6)
xx = zeros(endo_nbr,1); %initialize steady state vector
xx(1:M.orig_endo_nbr) = x(1:M.orig_endo_nbr); %set values of original endogenous variables based on steady state file or initial value
% setting steady state of auxiliary variables that depends on original endogenous variables
if any([M.aux_vars.type] ~= 6) %auxiliary variables other than multipliers
needs_set_auxiliary_variables = 1;
fh = str2func([M.fname '_set_auxiliary_variables']);
s_a_v_func = @(z) fh(z,...