It's compile a lot of mathematical matrix operations !
In Unreal Engine, we can change variables container (Single, Array, Set, Map) and the variable have relative functions and operations according to this. But it's impossible to set an Matrix container type.
But, a Matrix (or also says 2D Array) is very useful in many domains :
Pocedural, World/Dungeon Generation, Voxel, massive Data, Statistics, Wave Function Collapse etc...
You can Import / Export (Save / Load) Matrices from your computer with JSON file !*