3D Elevation graph (great for "daily by year" data)

Generate a 3d model of data in a grid (great for "daily data for a year")

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**Personal side note**

I added the two photos of the white graph after I originally posted this. The graph in those photos is particularly meaningful to me right now (March 22, 2020) as the world is living with the uncertainty of the COVID-19 ("Coronavirus") pandemic. The graph depicted in those photos shows the daily number of active (living, not recovered) COVID-19 cases in China from January 22 through March 20, 2020.

I live in the US, so why did I choose China? Because as of right now they are pretty much the only place in the world where the number of active cases is going down. This graph represents hope for the future, and the ability of humans to overcome challenges.

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This script (`daily-by-year-elevation-graph.scad`) generates a 3d model
consisting of a grid of cells (X and Y axes) The elevation (Z axis) of
each cell is defined by a value in an array of data.

It also (