This is documentation for Mathematica 6, which was
based on an earlier version of the Wolfram Language.
View current documentation (Version 11.2)

Apply (@@)

Apply[f, expr]
or f@@expr replaces the head of expr by f.
Apply[f, expr, levelspec]
replaces heads in parts of expr specified by levelspec.
  • Apply uses standard level specifications:
nlevels 1 through n
Infinitylevels 1 through Infinity
{n}level n only
{n1,n2}levels n1 through n2
  • The default value for levelspec in Apply is {0}.
  • f@@@expr is equivalent to Apply[f, expr, {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.
  • Apply always effectively constructs a complete new expression, and then evaluates it.
  • Apply operates on SparseArray objects just as it would on the corresponding ordinary lists.
New in 1 | Last modified in 4