Wrote

Just seems like it lends itself to manual creation of the vector used in the indices, but I suppose you just need to be creative enough.

... M:=Random.N(10,10,0,10) ... try range [-10,10]
It will fetch the [i,j] submatrix from where they originate,
either manually or else invention like here randomized

... ignore "Cannot find file"

Utilities Matrix Shuffle Random Extract.sm (12,57 KiB) descargado 1290 vez(es).

... more convivial version.

Utilities Matrix Shuffle Random Extract.sm (18,65 KiB) descargado 1355 vez(es).