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### 6.5 Functions for Vectors

Here are some functions that relate to vectors:

— Function: vectorp object

This function returns `t` if object is a vector.

```          (vectorp [a])
⇒ t
(vectorp "asdf")
⇒ nil
```
— Function: vector &rest objects

This function creates and returns a vector whose elements are the arguments, objects.

```          (vector 'foo 23 [bar baz] "rats")
⇒ [foo 23 [bar baz] "rats"]
(vector)
⇒ []
```
— Function: make-vector length object

This function returns a new vector consisting of length elements, each initialized to object.

```          (setq sleepy (make-vector 9 'Z))
⇒ [Z Z Z Z Z Z Z Z Z]
```
— Function: vconcat &rest sequences

This function returns a new vector containing all the elements of sequences. The arguments sequences may be proper lists, vectors, strings or bool-vectors. If no sequences are given, the empty vector is returned.

The value is either the empty vector, or is a newly constructed nonempty vector that is not `eq` to any existing vector.

```          (setq a (vconcat '(A B C) '(D E F)))
⇒ [A B C D E F]
(eq a (vconcat a))
⇒ nil
(vconcat)
⇒ []
(vconcat [A B C] "aa" '(foo (6 7)))
⇒ [A B C 97 97 foo (6 7)]
```

The `vconcat` function also allows byte-code function objects as arguments. This is a special feature to make it easy to access the entire contents of a byte-code function object. See Byte-Code Objects.

For other concatenation functions, see `mapconcat` in Mapping Functions, `concat` in Creating Strings, and `append` in Building Lists.

The `append` function also provides a way to convert a vector into a list with the same elements:

```     (setq avector [1 two (quote (three)) "four" [five]])
⇒ [1 two (quote (three)) "four" [five]]
(append avector nil)
⇒ (1 two (quote (three)) "four" [five])
```