F# Multidimensional Array Types

Question

What\'s the difference between \'a[,,] and \'a[][][]? They both represent 3-d arrays. It makes me write array3d.[x].[y].[z] instead of

Answer 1

As of F# 3.1 (2013) things are simpler:

As of F# 3.1, you can decompose a multidimensional array into subarrays of the same or lower dimension. For example, you can obtain a vector from a matrix by specifying a single row or column.

// Get row 3 from a matrix as a vector:
matrix.[3, *]

// Get column 3 from a matrix as a vector:
matrix.[*, 3]

See https://docs.microsoft.com/en-us/dotnet/fsharp/language-reference/arrays#array-slicing-and-multidimensional-arrays