`A(I)`

is an array formed from the elements of
`A`

specified by the subscript vector `I`

. The
resulting array is the same size as `I`

except for the special case
where `A`

and `I`

are both vectors. In this case,
`A(I)`

has the same number of elements as `I`

but has the orientation of `A`

.

`A(I,J)`

is an array formed from the elements of the rectangular
submatrix of `A`

, specified by the subscript vectors
`I`

and `J`

. The resulting array has
`length(I)`

rows and `length(J)`

columns. A
colon used as a subscript indicates all elements in that dimension. For example,
`A(I,:)`

means all columns of those rows specified by vector
`I`

. Similarly, `A(:,J)`

means all rows of
columns specified by `J`

.

`A(I,J,K,...)`

is the array specified by the subscripts. The
result is
`length(I)`

-by-`length(J)`

-by-`length(K)...`

.

`A{I}`

where `A`

is a cell array and
`I`

is a scalar forms a copy of the array in the specified cell
of `A`

. If `I`

has more than one element, this
expression is a comma-separated list. You can also use multiple subscripts that
specify a scalar element, as in `A{3,4}`

.

`A(I).field`

when `A`

is a structure array and
`I`

is a scalar forms a copy of the array in the field with the
name `field`

. If `I`

has more than one element,
this expression is a comma-separated list. If `A`

is a 1-by-1
structure array, then the subscript can be dropped. In this case,
`A.field`

is the same as `A(1).field`

.