I don't see how this improves upon the Stone-Weierstrass theorem, aside from expanding the range of functions that can uniformly approximate a continuous function or scatter plot. A scatter plot can be turned into a continuous function by setting the value to be the linear function that connects the two nearest data points, a piecewise linear function.
https://en.wikipedia.org/wiki/Stone%E2%80%93Weierstrass_theo...