id,node_id,number,title,user,state,locked,assignee,milestone,comments,created_at,updated_at,closed_at,author_association,active_lock_reason,draft,pull_request,body,reactions,performed_via_github_app,state_reason,repo,type
659142025,MDU6SXNzdWU2NTkxNDIwMjU=,4235,Dataset plot line,8419157,open,0,,,5,2020-07-17T10:51:24Z,2022-04-18T06:59:15Z,,NONE,,,,"<!-- Please do a quick search of existing issues to make sure that this has not been asked before. -->

**Is your feature request related to a problem? Please describe.**

`Dataset` have one plotting method `Dataset.plot.scatter`. This uses `matplotlb`'s `ax.scatter` which have a limited presentation configuration (eg  linestyle and marker).
I have 2D X and Y data which I like to plot against each other. The `DataArray.plot.line` works well if I only use a 1D X data.

**Describe the solution you'd like**

A new plotting method `Dataset.plot.line` based on `matplotlib`'s `ax.plot` which will allow me to plot 2D X and Y against each other with flexible presentation configuration. In other to be able to produce 1D lines, this must demand a required 3D dimension as an argument (eg a choice of `hue`, `col` or others).

I suspect that as increase in number of dimensions from 1D to 2D for both variables and later to ND, there will be many ways to interpret the arguments given to the plotting function,. However, the fact the method name is `line` in indicate that it must produce 1D lines, and use other dimensions to create other features such as legend or subplots.

Having seen the code for the `Dataset.plot.scatter` I am keen to submit a PR to add `Dataset.plot.line`.","{""url"": ""https://api.github.com/repos/pydata/xarray/issues/4235/reactions"", ""total_count"": 1, ""+1"": 1, ""-1"": 0, ""laugh"": 0, ""hooray"": 0, ""confused"": 0, ""heart"": 0, ""rocket"": 0, ""eyes"": 0}",,,13221727,issue