Inner

Inner[f,list1,list2,g]
is a generalization of Dot in which f plays the role of multiplication and g of addition.

DetailsDetails

  • Inner[f,{{a,b},{c,d}},{x,y},g]->{g[f[a,x],f[b,y]],g[f[c,x],f[d,y]]}.
  • Like Dot, Inner effectively contracts the last index of the first tensor with the first index of the second tensor. Applying Inner to a rank r tensor and a rank s tensor gives a rank tensor.
  • Inner[f,list1,list2] uses Plus for g.
  • Inner[f,list1,list2,g,n] contracts index n of the first tensor with the first index of the second tensor.
  • The heads of and must be the same, but need not necessarily be List. »

ExamplesExamplesopen allclose all

Basic Examples  (3)Basic Examples  (3)

Compute the "inner f" of two lists, with "plus operation" g:

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Compute a generalized inner product of a matrix and a vector:

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Use familiar operations:

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Introduced in 1988
(1.0)
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