Fix arrow color

[jstac]

Arrows in the graph in https://intro.quantecon.org/markov_chains_II.html#example-4 should be black, not red --- the same as the other figures.

[mmcky]

@jstac I didn't see any tikz code to generate this figure. Would the following networkx generated figure be ok?

[mmcky]

@kp992 have you used mermaid before?

https://mermaid.js.org

Wondering if we should give this a go for generating some of these figures. It will be natively available when we move over to mystjs so figures wouldn't need to be tracked as a static asset which would be great and in current jupyterbook we could use

https://github.com/mgaitan/sphinxcontrib-mermaid

• test compatibility with LaTeX outputs

[jstac]

Thanks fine @mmcky -- but mermaid sounds good. Does it support latex?

[mmcky]

Thanks fine @mmcky -- but mermaid sounds good. Does it support latex?

That's what I want to check.

I have transferred that part of this issue to QuantEcon/meta#140

The PR #420 is ready for review

[kp992]

https://github.com/QuantEcon/lecture-python-intro/blob/main/lectures/_static/lecture_specific/graphviz/graphviz_generation.ipynb cell number 8 has red color which seems to be the reason for this. Just removing that wouldn't fix the error?

[kp992]

@kp992 have you used mermaid before?

I haven't used it before, but I can have a look if its useful for us.

[kp992]

Using the below mermaid code:

graph LR;
    A((A)) -- 0.1 --> B((B))
    B -- 0.2 --> A

I was able to generate the following:

Moreover, https://sphinxcontrib-mermaid-demo.readthedocs.io/en/latest/#markdown-support also supports mermaid so we can give it a try on one of the lectures and see if this looks good.

[jstac]

https://github.com/QuantEcon/lecture-python-intro/blob/main/lectures/_static/lecture_specific/graphviz/graphviz_generation.ipynb cell number 8 has red color which seems to be the reason for this. Just removing that wouldn't fix the error?

Yep :-)

Let's do that.

[mmcky]

Thanks @kp992 -- do you know if there is a reason these are in a folder called graphviz?
I think we should split this ipynb up into figures.ipynb in each of the lecture folders to avoid this type of mistake.

[kp992]

do you know if there is a reason these are in a folder called graphviz?

I am not aware when this was added, but yeah, I agree that lecture-specific figures should be in their respective folders.