Vector variables

A vector is a one dimension array of double precision real numbers. A vector can be thought of as a list of numbers. There is no maximum length for vectors.

A literal vector can be a list of numbers, such as, `[3;4.2;.456;-8]`, or a range of numbers, such as, `[3:21:2]`, or an expression that results in a list of numbers, such as `3*[2:5]^2`.

Elements of a list are separated by semicolons, `;`, while the colon, `:`, is used as the range element separator.

The following table shows the possible ways that variables can be considered to be equivalent to vectors, that is, can be used wherever vectors are expected.

Let `a` be a scalar and let `x` be a vector. Suppose that `M` is a matrix and `V` is a vector.

`V` | = | `V[i]` | for `i = 1, ..., LEN(V)`
`V[x]` | = | `V[i]` | for `i = x[1], x[2], ..., x[#]`
`M[x,b]` | = | `M[i,a]` | for `i = x[1], x[2], ..., x[#]`
`M[a,x]` | = | `M[a,j]` | for `j = x[1], x[2], ..., x[#]`

All vectors have an order property. Vectors are either in ascending order, descending order, or un-ordered. The type is displayed in the `SHOW` command, where `+O` means ascending order, `-O` means descending order, and no symbol means un-ordered. For now, being ordered only has an affect on the vector union, `/|`, and the vector intersection, `/&`, operators. These operations are much faster if the vector operands are ordered. The `WHERE` function produces an ascending order vector, as does the `SORT/UP` command. The `SORT/DOWN` command produces a descending order vector.

Scalar variables
Matrix variables