# Ttr lyapunovspectrum DynamicalSystems.jl

**URL:** <https://discourse.julialang.org/t/ttr-lyapunovspectrum-dynamicalsystems-jl/86206>\
**Category:** Modelling & Simulations\
**Created:** [August 23, 2022, 3:51pm UTC](https://discourse.julialang.org/t/ttr-lyapunovspectrum-dynamicalsystems-jl/86206 "2022-08-23T15:51:38Z")\
**Posts on this page:** 4\
**Page:** 1

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**Author:** ![Sergey\_Novak](https://sea2.discourse-cdn.com/julialang/user_avatar/discourse.julialang.org/sergey_novak/32/37716_2.png) [@Sergey\_Novak](https://discourse.julialang.org/u/Sergey_Novak)\
**Post date:** [August 23, 2022, 3:51pm UTC](https://discourse.julialang.org/t/ttr-lyapunovspectrum-dynamicalsystems-jl/86206/1 "2022-08-23T15:51:38Z")

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I have code:

```julia
lyapunovspectrum(ds, 300000.0;
                    Ttr = 200000.0,
                    diffeq = (alg = Vern9(),
                              abstol = 1e-11, reltol = 1e-11, dense = false, maxiters = 10000000) )

```

How correctly use `Ttr`. I need to start algorithm when transient process is ended. The transition process can last quite a long time. Is there any way to make sure it has been completed?

Spectrum:  
 ![image](https://global.discourse-cdn.com/julialang/original/3X/8/d/8d18a5a9a500c53ff5c7bf1307058adde44deab3.png)

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<div class="post-metadata">

**Author:** ![Datseris](https://sea2.discourse-cdn.com/julialang/user_avatar/discourse.julialang.org/datseris/32/13406_2.png) [@Datseris](https://discourse.julialang.org/u/Datseris)\
**Post date:** [August 23, 2022, 4:07pm UTC](https://discourse.julialang.org/t/ttr-lyapunovspectrum-dynamicalsystems-jl/86206/2 "2022-08-23T16:07:38Z")

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nope, unfortunately no system agnostic way to know this. Perhaps you should de-dimensionalize your equations so the time units aren’t so huge.

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<div class="post-metadata">

**Author:** ![Sergey\_Novak](https://sea2.discourse-cdn.com/julialang/user_avatar/discourse.julialang.org/sergey_novak/32/37716_2.png) [@Sergey\_Novak](https://discourse.julialang.org/u/Sergey_Novak)\
**Post date:** [August 23, 2022, 4:11pm UTC](https://discourse.julialang.org/t/ttr-lyapunovspectrum-dynamicalsystems-jl/86206/3 "2022-08-23T16:11:13Z")

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Is there no way to set Tr so that the algorithm starts at 60% of the specified time?

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<div class="post-metadata">

**Author:** ![Sergey\_Novak](https://sea2.discourse-cdn.com/julialang/user_avatar/discourse.julialang.org/sergey_novak/32/37716_2.png) [@Sergey\_Novak](https://discourse.julialang.org/u/Sergey_Novak)\
**Post date:** [August 23, 2022, 4:21pm UTC](https://discourse.julialang.org/t/ttr-lyapunovspectrum-dynamicalsystems-jl/86206/4 "2022-08-23T16:21:45Z")

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I have a more theoretical question related to the algorithm. If the system has multistability, then how should the spectrum be calculated so that it corresponds to the required attractor.

For example attractor with regular mode

 ![image](https://global.discourse-cdn.com/julialang/original/3X/b/1/b1419f44002548e24845a914a5ede2b7e7edd97d.png)  
 ![image](https://global.discourse-cdn.com/julialang/original/3X/4/0/405578c981bfafe4d920f7ffa19ee716912ad42f.png)  
When i calculate spectrum with initial condition from this attractor i have result how for another attractor, which hyperchaotic  
Is it solely related to the system or maybe it’s the algorithm