**Defined in theory: Tensor-quantities****Source code: tensor-quantities.lisp**

**Documentation:**The class of second order tensors (aka tensors). Given an orthornormal basis a dyad can be decomposed into scalar components. These components can be represented as a square matrix. The matrix is not unique but it a 'view' of the tensor for a particular basis.

**Subclass-Of:**Constant-quantity, Tensor-quantity

**Tensor-Order:**2

(<=> (Dyad ?D) (And (Constant-Quantity ?D) (Tensor-Quantity ?D) (= (Tensor-Order ?D) 2) (Forall (?B ?I ?J) (=> (And (Orthonormal-Basis ?B) (= (Basis.Dimension ?B) (Spatial.Dimension ?D)) (Positive-Integer ?I) (=< ?I (Spatial.Dimension ?D)) (Positive-Integer ?J) (=< ?J (Spatial.Dimension ?D))) (And (Defined (Dyad-Component ?D ?I ?J ?B)) (= (Quantity.Dimension (Dyad-Component ?D ?I ?J ?B)) (Quantity.Dimension ?D))))) (Forall (?U) (=> (And (Unit-Of-Measure ?U) (= (Quantity.Dimension ?U) (Quantity.Dimension ?D))) (Numeric-Tensor (Magnitude ?D ?U))))))