guide: Params, Plots and Metrics

[iesahin]

The current documentation includes information on plots and metrics in the command reference for dvc plots and dvc metrics. We need a self-contained UG page for all features regarding the plots and metrics.

• Extract details from https://dvc.org/doc/user-guide/project-structure/dvcyaml-files#stages
• Extract some details from params and metrics ref. indices.
  See also params: clarify when they're granular #4202
• Maybe clarify the concept of params* as well.
• Keep in mind conceptual and terminology decisions in ref: clarify about types of metrics/plots #2956

Related

• plots: document html template #2472 contains a page that describes offline usage of Vega libraries
• ref: Update dvc plots to include information about offline HTML plots #2402 is the issue around offline usage
• guide: using metrics/plots and params without pipelines #2216 contains some information about using plots/metrics without pipelines
• term: call metrics "metrics" and plots "plots" #1442 is terminology issue around plots and metrics
• metrics/plots: clarify when/why to cache metrics/plots files or not (Git vs DVC tracking) #1755 asks for clarification where to use DVC or Git to track the plots and metrics
• metrics: document behavior of accepting any parsable file #1909 is about the capability of metrics and plots to work with any parsable file
• cmd: update metrics/plots docs per recent changes #1175 is also a terminology issue
• plots: move explanations from cmd ref to guide #3818
• glossary: add "metrics" and "plots" #2644

[daavoo]

Related?: #2644

[jorgeorpinel]

From #2815

We briefly cover those 3 types of files in the Project Structure -> Pipeline Files -> Stages section.
However, it feels like the current info in each command reference could be moved to the user guide, potentially extending it.

[jorgeorpinel]

Explain params metafiles
metrics and plots metafiles

Should these be tasks in #2911 since params, metrics and plots are mainly experiment tracking mechanisms? (Correct me if I'm wrong.)

[iesahin]

Conceptually these are rather closer to experiment management. However, I think metrics that's relevant to dvc exp commands are covered (implicitly) in dvc exp show. dvc metrics command is related to pipelines in its current usage.

I think having a separate metrics/plots guide that describes these in pipelines and experiments context may be a better approach.