The needle and the haystack: visualizing single datapoints out of billions
07-19, 14:35–15:05 (Europe/Prague), North Hall

Python tools like Bokeh and Dash let you build custom Web-based interactive visualization apps and dashboards. While these solutions work well to visualize megabyte-sized datasets, web technologies struggle to render gigabyte or larger datasets efficiently, because they transfer all the data into the client browser. Pre-rendering the data on the server using a tool like Datashader can visualize such large datasets efficiently, but the resulting static renderings make exploring individual datapoints difficult.

This talk demonstrates how the HoloViz ecosystem of tools ( allows you to run exploratory notebooks and build dashboards that do server-side rendering of billions of data points without losing the ability to interactively inspect and annotate individual samples in the browser.

Expected audience expertise