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NonCommutativeMultiply

  • a ** b ** c is a general associative, but non-commutative, form of multiplication.
  • NonCommutativeMultiply has attribute Flat.
  • Instances of NonCommutativeMultiply are automatically flattened, but no other simplification is performed.
  • You can use NonCommutativeMultiply as a generalization of ordinary multiplication for special mathematical objects.
  • See the Mathematica book: Section A.2.7.
  • See also: Dot, Times, Cross.

    Further Examples

    Multiplication is a commutative operation.

    In[1]:=

    Out[1]=

    But the noncommutative operator ** does not have this property.

    In[2]:=

    Out[2]=