Swizzling! (Or pandas DataFrame "reshaping" / "pivoting" / "(un)stacking".)
Click and drag the i,j,k in the upper right to reorder. Click anywhere else to donate to ACLU or CAIR. Refresh for random dimensions.
One can imagine more spreadsheety stuff, extending to 4D arrays and higher, and aggregating/slicing/collapsing/folding along different dimensions.
No, I'm not at all sure I'm using the term "swizzle" correctly. I don't understand matrices.