Hopefully this is the correct forum for a datashader question.
I have what I thought would be a relatively small amount of data that I want to represent in a heatmap, 21,000 points. I tried to do with with client side plotly in JS, and the browser crashes. Plotly told me that was because my data was 1D and they require 2D and it crashed doing the conversion, and if I did the conversation in the backend and passed them 2d data it would not crash. But when I did that the resultant JSON data was 11G. No way could I pass that much data to the browser. Wondering why it was go large I found that when converting to 2d there has be a value at each 21k X 21k coordinate locations (441M). But most of those values are None (or 0) - there are only values at 21,000 of those locations.
Googling for a way to deal with this I came across datashader, and it seemed perfect for my situation. But when I generate a heatmap with my data I get one single color. I think what is happening is that because most of the points have a 0 value that is the min and is colored with violet and even though there may be other colors in there the 440,979,000 violet points totally obscure the 21,000 points with other colors.
Can anyone tell me how to get around this issue so my 21k points of interest can be seen?
I can post my code if that would be helpful.