Improve HoloViz/DataShader Map Visualization & User Interaction Capabilities (GSoC Project 2)

[mwengren]

Project Description:

Note: this project should be done in combination with #24 to develop an overall dashboard/map application for a colocate GUI. Interested students should submit applications that consider both this issue #16 and #24 together.

Presently, the colocate-dev notebook uses HoloViz & DataShader to display nearly unlimited features on a slippy map.

See the Binder link for a preview: .

Example graphic:

The code backing the DataShader-based map is in the plot_datashader() function in plot.py. It is messy/WIP code that needs to be revised, and also recent releases of HoloViews have enabled many new capabilities for DataShader maps such as hover, colorbars, and dynamic color maps and more that would improve our map presentation.

Some simple improvements to the plotting interface might be:

• enable hover functionality with relevant attributes like dataset ID, lat/lon, etc
• add a legend to the plot showing dataset ID
• figure out how to increase marker size to better show single-point datasets that are drowned out by trajectories

More advanced changes:

• enable user to dynamically select datasets to plot from query results table
• other dynamic plotting capabilities (varying plot display based on CF featureType for example)

Expected Outcomes:
An improved HoloViz map display that better displays ERDDAP dataset results and might integrate better with other dashboard-like capabilities planned for the project (#24)

Skills required:
Python: HoloViz, DataShader, Panel API familiarity especially

Difficulty:
Medium

Student Test:

• Fork the repository
• Run the colocate-dev.ipynb in Binder to get an idea for the current DataShader map display in the output of Cell 12
• Improve the code in colocate/plot.py plot_datashader() so the map is able to meet one of the 'simple improvements' listed above
• Push your changes to your GitHub fork and post a link to run your modified colocate-dev.ipynb notebook in this issue

Mentor(s):
Micah Wengren @mwengren, Mathew Biddle @MathewBiddle

[mwengren]

Superseded by #29