exporting data?

I have a smoke scene that I have been rendering to 2D images, but I would like to export the entire 3D data set. I am not sure what form this would take - would it be (x,y,z,D) data (where D is the local density or color)? What kinds of options are there for exporting this? Other software I’ve used will export the (x,y,z) coordinates for the grid, then relevant data at each point.

Thank You!