[*]

All elements of a dimension.

This form is used with multidimensional arrays to select all elements along the dimension. For example, if arr is a 10-column by 12-row array, arr[*, 11] is the last row of arr, composed of elements [arr[0,11], arr[1,11], ..., arr[9,11]], and is a 10-element row vector. Similarly,arr[0, *] is the first column of arr, [arr[0,0], arr[0,1],..., arr[0,11]], and its dimensions are 1 column by 12 rows.

[s₀:s₁]

Subscript range from s₀ to s₁.

This denotes all elements whose subscripts range from the expression s₀ through s₁(s₀ must not be greater than s₁). For example, if the variable vec is a 10-element vector, vec[4:8] is a five-element vector composed of vec[4] through vec[8]. Negative indices may be used, where -1 indicates the last element. For example, vec[-6:-2] returns the same five elements as vec[4:8].

[s₀:*]

or

[s₀:-1]

A range from the given element to the last element of dimension.

This denotes all elements from a given element to the last element of the dimension. If the variablevec is a 50-element vector, vec[10:*] is a 40-element vector made from vec[10] through vec[49].

[s₀:s₁:n]

Every n-th element in a range of subscripts from s₀ to s₁.

The expression n is referred to as the subscript stride. The stride value may be positive or negative (but must not be zero). If the stride is positive then s₀ must be less than or equal to s₁. If the stride is negative then s₀ must be greater than or equal to s₁. If the stride is 1, then the result is identical in meaning to [s₀:s₁], as described above. For example, if the variable vec is a 50-element vector,vec[5:13:2] is a five-element vector composed of vec[5], vec[7], vec[9], vec[11], and vec[13]. In another example, vec[-1:0:-3] would return every third element of vec, in reverse order.

[s₀:*:n]

or

[s₀:-1:n]

Every n-th element from element s₀ to the end of the dimension.

The expression n is referred to as the subscript stride. If the variable vec is a 50-element vector,vec[10:*:4] is a 10-element vector made from every fourth element between vec[10] throughvec[46].

[n]

A simple subscript, either positive or negative.

Positive subscripts are indexed from the beginning of the array, while negative subscripts are indexed from the end (where -1 is the last element). When used with multidimensional arrays, simple subscripts specify only elements with subscripts equal to the given subscript in that dimension.