Configure minimum space between nodes in dynamic graphs

[r-weng]

Proposed Changes

This pull request uses nodesep to configure minimum space between nodes in dynamic graphs.

This doesn't entirely fix the arrowhead issue I mentioned a few presentations ago (where some arrowheads do not appear properly connected to their respective dotted lines due to the lack of an additional line segment), but it mitigates it. See screenshots below, and notice how (1) the arrow from MAT148H1 to the and node and (2) the arrow from MAT158H1 to the and node change.

...

Screenshots of your changes (if applicable)

(without `nodesep`) (with `nodesep`)

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Questions and Comments

I tried playing around with other splines configurations (as listed in the link below), which allow edges to be diagonal or rounded. This fixed the arrowhead issue, but the existing configuration, ortho, looked the cleanest and most consistent with the main graph, especially as the number of nodes and edges increased.

https://graphviz.org/docs/attrs/splines/

I also was not able to use dot attributes to set coordinates for the graph (I don't think it's possible).

[coveralls]

Coverage Report for CI Build 0

Coverage increased (+0.007%) to 58.602%

Details

• Coverage increased (+0.007%) from the base build.
• Patch coverage: 1 of 1 lines across 1 file are fully covered (100%).
• No coverage regressions found.

Uncovered Changes

No uncovered changes found.

Coverage Regressions

No coverage regressions found.

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Coverage Stats

Relevant Lines:	4286
Covered Lines:	2563
Line Coverage:	59.8%
Relevant Branches:	1009
Covered Branches:	540
Branch Coverage:	53.52%
Branches in Coverage %:	Yes
Coverage Strength:	155.62 hits per line

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💛 - Coveralls

[r-weng]

Drafting because I just noticed the MAT137 to or edge 😭

[r-weng]

Drafting because I just noticed the MAT137 to or edge 😭

I don't think this can be fixed just by configuring Graphviz dot attributes. The closest I got to fixing the edge and arrowhead issues was changing the splines configuration from ortho to curved, but it looks a bit messy for bigger graphs, as shown below.

[david-yz-liu]

Thanks @r-weng! I appreciate the investigation into this, and I do think the graph looks a bit nicer with the minimum nodesep set. I agreed that the ortho setting was cleanest and most consistent with the existing hand-crafted Courseography graph.