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TagSetDelayed

  • f /: lhs := rhs assigns rhs to be the delayed value of lhs, and associates the assignment with the symbol f.
  • See notes for TagSet and SetDelayed.
  • See the Mathematica book: Section 2.4.10.

    Further Examples

    Nothing is done here.

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    This defines a rule for the product of Sin and Cos and associates that rule with the Sin function. Sin has to be unprotected first.

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    By storing the rule with Sin instead of the top level operation Times, you avoid slowing down every computation with Times.

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    We restore the original behavior of Sin. Clear does not get rid of the built-in definitions for Sin.

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