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 Documentation / Mathematica / Built-in Functions / Mathematical Functions / Basic Arithmetic  /
Plus

  • x + y + z represents a sum of terms.
  • Plus has attributes Flat, Orderless and OneIdentity.
  • The default value for arguments of Plus, as used in x_. patterns, is 0.
  • Plus[ ] is taken to be 0.
  • Plus[ x ] is x.
  • x + 0 evaluates to x, but x + 0.0 is left unchanged.
  • Unlike other functions, Plus applies built-in rules before user-defined ones. As a result, it is not possible to make definitions such as 2+2=5.
  • See the Mathematica book: Section 1.1.1.
  • See also: Minus, Subtract, AddTo, Increment.

    Further Examples

    This is a fast way to add up the elements of a list.

    In[1]:=

    Out[1]=

    This shows how a sum is represented internally.

    In[2]:=

    Out[2]//FullForm=