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.
Details and Options

- 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 an Association object, Map[f,expr] applies f to the values in the association.
- If expr is a SparseArray object, Map[f,expr] applies f to the values or subarrays that appear in expr.
- Map[f][expr] is equivalent to Map[f,expr].
Examples
open allclose allBasic Examples (8)
Map a function over values in Association:
Map at the second level of a nested Association:
Map at several levels in an Association:
Scope (6)
Generalizations & Extensions (4)
Options (1)
Applications (4)
Properties & Relations (5)
Possible Issues (1)
Neat Examples (1)
See Also
Apply Scan MapAll MapAt MapIndexed MapThread AssociationMap KeyMap KeyValueMap Level Operate Through Thread ParallelMap ImageApply
Tutorials
Related Guides
Related Links
Introduced in 1988
(1.0)
| Updated in 2014 (10.0)