Span

i;;j

represents a span of elements i through j.

i;;

represents a span from i to the end.

;;j

represents a span from the beginning to j.

;;

represents a span that includes all elements.

i;;j;;k

represents a span from i through j in steps of k.

i;;;;k

represents a span from i to the end in steps of k.

;;j;;k

represents a span from the beginning to j in steps of k.

;;;;k

represents a span from the beginning to the end in steps of k.

Details

  • m[[i;;j;;k]] is equivalent to Take[m,{i,j,k}].
  • m[[i;;j]]=v can be used to reset a span of elements in a list or other expression.
  • When used in Part, negative i and j count from the end.

Examples

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Basic Examples  (2)

Take a span of elements from a list:

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Assign to a span of elements:

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In[2]:=
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In[3]:=
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Assign a sequence of different elements:

In[4]:=
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In[5]:=
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Scope  (1)

See Also

Take  Drop  Part  Range  Band

Introduced in 2007
(6.0)