Part

expr[[i]] or Part[expr, i] gives the part of expr.

expr[[-i]] counts from the end.

expr[[i, j, ... ]] or Part[expr, i, j, ... ] is equivalent to expr[[i]] [[j]] ... .

expr[[{, , ... }]] gives a list of the parts , , ... of expr.

You can make an assignment like t[[i]] = value to modify part of an expression.

When expr is a list, expr[[{, , ... }]] gives a list of parts. In general, the head of expr is applied to the list of parts.

You can get a nested list of parts from expr[[, , ... ]]. Each part has one index from each list.

expr[[spec]] can be input as exprspec.

and can be entered as [[ and ]] or \[LeftDoubleBracket] and \[RightDoubleBracket].

expr[[spec]] can be input as or .

See also: First, Last, Position, Take.

Examples

Using InstantCalculators

Here are the InstantCalculators for the Part function. Enter the parameters for your calculation and click Calculate to see the result.

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Entering Commands Directly

You can paste a template for this command via the Text Input button on the Part Function Controller.

This finds the third element from the list using the shorthand notation for Part.

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This pulls out a list of elements.

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The second input resets the third element of the list using the special characters for Part.

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Clear the variable definition.

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