contract'(Matrix,Matrix) -- contract a matrix by a matrix, the dual notion

Synopsis

• Function: contract'
• Usage:
h = contract'(m,n)
• Inputs:
• m, , a map m : F <--- P between free modules of ranks f and p.
• n, , a map n : G <--- Q between free modules of ranks g and q.
• Outputs:
• h, , a matrix with the shape h : F ** dual G <--- P ** dual Q, whose entry in the slot hg*i+j,q*k+l is the result of contracting mi,k, by nj,l.

Description

This function is identical to diff'(Matrix,Matrix), except that the multiplication by integers that occurs during differentiation is omitted.