# Steady state about equation sets

**URL:** <https://forum.dynare.org/t/steady-state-about-equation-sets/19723>\
**Category:** Steady state\
**Created:** [1 February 2022 09:15 UTC](https://forum.dynare.org/t/steady-state-about-equation-sets/19723 "2022-02-01T09:15:43Z")\
**Posts on this page:** 4\
**Page:** 1

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**Author:** ![swade](https://forum.dynare.org/letter_avatar_proxy/v4/letter/s/c89c15/32.png) [@swade](https://forum.dynare.org/u/swade)\
**Post date:** [1 February 2022 09:15 UTC](https://forum.dynare.org/t/steady-state-about-equation-sets/19723/1 "2022-02-01T09:15:44Z")

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dear all:  
i have a problem about how to calculate the steady state of equation set.there are two equations of Tat\_ss and Tlo\_ss,but the steady state can’t calculate directly,so i write a function to do it.there are the results of it.how can i do next?many thanks!

> > dynare fangyeoceansink.mod  
> > Using 64-bit preprocessor  
> > Starting Dynare (version 4.6.4).  
> > Calling Dynare with arguments: none  
> > Starting preprocessing of the model file …  
> > Found 38 equation(s).  
> > Evaluating expressions…done  
> > Computing static model derivatives (order 1).  
> > Computing dynamic model derivatives (order 1).  
> > Processing outputs …  
> > done  
> > Preprocessing completed.

数组索引必须为正整数或逻辑值。

出错 wei (第 2 行)  
Tat\_ss=Tat\_ss(-1)+0.048\*(2-1.37_Tat\_ss(-1)-0.44_(Tat\_ss(-1)-Tlo\_ss(-1)));

出错 fsolve (第 260 行)  
fuser = feval(funfcn{3},x,varargin{:});

出错 fangyeoceansink.driver (第 768 行)  
M\_.params(82) = fsolve(fun,x0);

出错 dynare (第 293 行)  
evalin(‘base’,[fname ‘.driver’]) ;

原因:  
Failure in initial objective function evaluation. FSOLVE cannot continue.  
[fangyeoceansink.mod](https://forum.dynare.org/uploads/short-url/y7l5NsNDfUB2455bnFAhCZRDSsd.mod) (9.5 KB)  
[wei.m](https://forum.dynare.org/uploads/short-url/xzJOomdaFxK0yjQyy7CiXsphSMk.m) (181 Bytes)

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**Author:** ![jpfeifer](https://forum.dynare.org/user_avatar/forum.dynare.org/jpfeifer/32/5044_2.png) [@jpfeifer](https://forum.dynare.org/u/jpfeifer)\
**Post date:** [1 February 2022 15:57 UTC](https://forum.dynare.org/t/steady-state-about-equation-sets/19723/2 "2022-02-01T15:57:14Z")

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Please clearly outline the two equations of the system you are trying to solve. Use the forum’s \LaTeX-capabilities for that, i.e. enclose the code in Dollar signs. The equation you have in the Matlab function

```auto
         Tat_ss=Tat_ss(-1)+0.048*(2-1.37*Tat_ss(-1)-0.44*(Tat_ss(-1)-Tlo_ss(-1)));
         Tlo_ss=Tlo_ss(-1)+0.002*(Tat_ss(-1)-Tlo_ss(-1));

```

is still a dynamic equation that cannot be solved. Also, these are two linear equations in two unknowns. Why can’t you solve them by hand?

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<div class="post-metadata">

**Author:** ![swade](https://forum.dynare.org/letter_avatar_proxy/v4/letter/s/c89c15/32.png) [@swade](https://forum.dynare.org/u/swade)\
**Post date:** [3 February 2022 02:52 UTC](https://forum.dynare.org/t/steady-state-about-equation-sets/19723/3 "2022-02-03T02:52:33Z")

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thank you,dear professor. so how can i do by hand?

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<div class="post-metadata">

**Author:** ![jpfeifer](https://forum.dynare.org/user_avatar/forum.dynare.org/jpfeifer/32/5044_2.png) [@jpfeifer](https://forum.dynare.org/u/jpfeifer)\
**Post date:** [3 February 2022 08:57 UTC](https://forum.dynare.org/t/steady-state-about-equation-sets/19723/4 "2022-02-03T08:57:25Z")

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If you did not learn how to solve systems of linear equations in school, I am afraid I cannot help you. You may want to Google it.