# CellmlToolkit.jl: How to get observables?
**URL:** https://discourse.julialang.org/t/cellmltoolkit-jl-how-to-get-observables/69151
**Category:** Modelling & Simulations
**Tags:** question
**Created:** [October 3, 2021, 9:02pm UTC](https://discourse.julialang.org/t/cellmltoolkit-jl-how-to-get-observables/69151 "2021-10-03T21:02:00Z")
**Posts on this page:** 4
**Page:** 1
### Author:  [@andreypikunov](https://discourse.julialang.org/u/andreypikunov)
#### Post date: [October 3, 2021, 9:02pm UTC](https://discourse.julialang.org/t/cellmltoolkit-jl-how-to-get-observables/69151/1 "2021-10-03T21:02:00Z")
Hello!
Using Beeler-Reuter model from the [README](https://github.com/SciML/CellMLToolkit.jl#cellmltoolkitjl) I can list **observables** :
```julia
julia> ml = CellModel("models/beeler_reuter_1977.cellml.xml")
julia> observed(ml.sys)
39-element Vector{Equation}:
slow_inward_current_f_gate₊V(time) ~ membrane₊V(time)
slow_inward_current₊f(time) ~ slow_inward_current_f_gate₊f(time)
⋮
time_dependent_outward_current₊i_x1(time) ~ membrane₊i_x1(time)
slow_inward_current₊i_s(time) ~ membrane₊i_s(time)
julia> ml.sys.membrane₊i_Na
var"##ODESystem#257₊membrane₊i_Na"(time)
```
But I do not understand how to get them calculated over time (and then plot, for example) after I solve the model.
For example, I would like to do this like:
```julia
prob = ODEProblem(ml, (0, 42.0))
sol = solve(prob)
sol[membrane₊i_Na]
```
but this does not work.
Could you help me?
---
### Author:  [@ChrisRackauckas](https://discourse.julialang.org/u/ChrisRackauckas)
#### Post date: [October 4, 2021, 2:56pm UTC](https://discourse.julialang.org/t/cellmltoolkit-jl-how-to-get-observables/69151/2 "2021-10-04T14:56:36Z")
> [@andreypikunov](#):
>
> ```julia
> prob = ODEProblem(ml, (0, 42.0))
> sol = solve(prob)
> sol[membrane₊i_Na]
>
> ```
```julia
prob = ODEProblem(ml, (0, 42.0))
sol = solve(prob)
sys = ml.sys
sol[@nonamespace sys.membrane₊i_Na]
```
This is missing docs so I just pinged @YingboMa to make sure the namespacing gets documented.
---
### Author:  [@andreypikunov](https://discourse.julialang.org/u/andreypikunov)
#### Post date: [October 20, 2021, 2:15pm UTC](https://discourse.julialang.org/t/cellmltoolkit-jl-how-to-get-observables/69151/3 "2021-10-20T14:15:39Z")
Thank you!
`@nonamespace` did everything I needed.
🙂
---
### Author:  [@ChrisRackauckas](https://discourse.julialang.org/u/ChrisRackauckas)
#### Post date: [October 20, 2021, 2:19pm UTC](https://discourse.julialang.org/t/cellmltoolkit-jl-how-to-get-observables/69151/4 "2021-10-20T14:19:59Z")
And we can make that a bit more automatic in the near future.