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Mathematica > Parts of Expressions >

Built-in Mathematica Symbol

Extract

Extract[expr, list]
extracts the part of expr at the position specified by list.

Extract[expr, {list₁, list₂, ...}]
extracts a list of parts of expr.

Extract[expr, list, h]
extracts parts of expr, wrapping each of them with head h before evaluation.

The position specifications used by Extract have the same form as those returned by Position, and used in functions such as MapAt and ReplacePart.

If expr is a SparseArray object, Extract[expr, ...] extracts parts in the corresponding ordinary array.

Extract the second part from an expression:

Extract a part nested in an expression:

Extract the parts given by Position: