Type syntax

  Let T<[d1, …, dn], ty> be a tensor of order n with dimensions d1, … dn

  Let DATA_m<[d1, …, dn], ty> be a tensor dataset of m dimensions

  Let F_m<[d1, …, dn], ty> be a tensor field of m dimensions

Basic operations:

  The gradient of a scalar field

	D : F_m<[], ty> -> F_,<[m], ty>

  The Hessian of a scalar field

	D o D : F_m<[], ty> -> F_,<[m,m], ty>

  The eigenvalues of a symmetric matrix

	lambda : F_m<[d,d], ty> -> F_m<[d], ty>

Patterns:

  The eigenvalues of the H