Vector and Matrix Multiply Intrinsics

There are two types of intrinsic matrix multiplication:

• DOT_PRODUCT(VEC1, VEC2) -- inner (dot) product of two rank 1 arrays.

  For example,

      DP = DOT_PRODUCT(A,B)

  is equivalent to:

      DP = A(1)*B(1) + A(2)*B(2) + ...

  For LOGICAL arrays, the corresponding operation is a logical .AND..

      DP = LA(1) .AND. LB(1) .OR. &
           LA(2) .AND. LB(2) .OR. ...

• MATMUL(MAT1, MAT2) -- `traditional' matrix-matrix multiplication:
  • if MAT1 has shape (n, m) and MAT2 shape (m, k) then the result has shape (n, k);
  • if MAT1 has shape (m) and MAT2 shape (m, k) then the result has shape (k);
  • if MAT1 has shape (n, m) and MAT2 shape (m) then the result has shape (n);

  For LOGICAL arrays, the corresponding operation is a logical .AND..

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