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Map (/@)

Map[f, expr] or f/@expr
applies f to each element on the first level in expr.

Map[f, expr, levelspec]
applies f to parts of expr specified by levelspec.

MORE INFORMATION

Map uses standard level specifications:

	n	levels 1 through n
	Infinity	levels 1 through Infinity
	{n}	level n only
	{n₁,n₂}	levels n₁ through n₂

The default value for levelspec in Map is {1}.

A positive level n consists of all parts of expr specified by n indices.

A negative level -n consists of all parts of expr with depth n.

Level -1 consists of numbers, symbols and other objects that do not have subparts.

Level 0 corresponds to the whole expression.

With the option setting Heads->True, Map includes heads of expressions, and their parts.

Map always effectively constructs a complete new expression, and then evaluates it.

If expr is a SparseArray object, Map[f, expr] applies f to the values or subarrays that appear in expr.

Basic Examples (4)

Alternative input form:

Use explicit pure functions:

Map at top level:

Map at level 2:

Map at levels 1 and 2:

Generalizations & Extensions (4)

Applications (3)

Properties & Relations (5)

Possible Issues (1)

Neat Examples (1)

Apply Scan MapAll MapAt MapIndexed MapThread Level Operate Through Thread ParallelMap ImageApply

Applying Functions to Parts of Expressions

Demonstrations with Map (Wolfram Demonstrations Project)

NKS|Online (A New Kind of Science)

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