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Unset

  • lhs =. removes any rules defined for lhs.
  • Rules are removed only when their left-hand sides are identical to lhs, and the tests in Condition given on the right-hand side are also identical.
  • See the Mathematica book: Section 1.4.2, Section 2.4.3Section A.5.4.
  • See also: Clear, TagUnset.

    Further Examples

    This assigns a value to the symbol a, uses that value in a calculation, unsets the definition, and tries the same calculation again.

    In[1]:=

    Out[1]=

    In[2]:=

    Out[2]=

    In[3]:=

    In[4]:=

    Out[4]=