Next: , Previous: , Up: Vectors   [Contents][Index]

8.1 Construction of Vectors

procedure: make-vector k [object]

Returns a newly allocated vector of k elements. If object is specified, `make-vector` initializes each element of the vector to object. Otherwise the initial elements of the result are unspecified.

procedure: vector object …

Returns a newly allocated vector whose elements are the given arguments. `vector` is analogous to `list`.

```(vector 'a 'b 'c)                       ⇒  #(a b c)
```
procedure: vector-copy vector

Returns a newly allocated vector that is a copy of vector.

procedure: list->vector list

Returns a newly allocated vector initialized to the elements of list. The inverse of `list->vector` is `vector->list`.

```(list->vector '(dididit dah))           ⇒  #(dididit dah)
```
standard procedure: string->vector string [start [end]]
standard procedure: vector->string vector [start [end]]

It is an error if any element of vector is not a character.

The `vector->string` procedure returns a newly allocated string of the objects contained in the elements of vector between start and end. The `string->vector` procedure returns a newly created vector initialized to the elements of the string string between start and end.

In both procedures, order is preserved.

```(string->vector "ABC")                  ⇒  #(#\A #\B #\C)
(vector->string #(#\1 #\2 #\3)          ⇒  "123"
```
procedure: make-initialized-vector k initialization

Similar to `make-vector`, except that the elements of the result are determined by calling the procedure initialization on the indices. For example:

```(make-initialized-vector 5 (lambda (x) (* x x)))
⇒  #(0 1 4 9 16)
```
procedure: vector-grow vector k

K must be greater than or equal to the length of vector. Returns a newly allocated vector of length k. The first `(vector-length vector)` elements of the result are initialized from the corresponding elements of vector. The remaining elements of the result are unspecified.

standard procedure: vector-map procedure vector vector …

It is an error if procedure does not accept as many arguments as there are vectors and return a single value.

The `vector-map` procedure applies procedure element-wise to the elements of the vectors and returns a vector of the results, in order. If more than one vector is given and not all vectors are the same length, `vector-map` terminates when the shortest vector runs out. The dynamic order in which procedure is applied to the elements of the vectors is unspecified. If multiple returns occur from `vector-map`, the values returned by earlier returns are not mutated.

```(vector-map cadr '#((a b) (d e) (g h))) ⇒  #(b e h)
(vector-map (lambda (n) (expt n n)) '#(1 2 3 4 5))
⇒  #(1 4 27 256 3125)
(vector-map + '#(1 2 3) '#(4 5 6 7))    ⇒  #(5 7 9)
(let ((count 0))
(vector-map (lambda (ignored)
(set! count (+ count 1))
count)
'#(a b)))                 ⇒ #(1 2) or #(2 1)
```
standard procedure: vector-for-each procedure vector vector …

It is an error if procedure does not accept as many arguments as there are vectors.

The arguments to `vector-for-each` are like the arguments to `vector-map`, but `vector-for-each` calls procedure for its side effects rather than for its values. Unlike `vector-map`, `vector-for-each` is guaranteed to call procedure on the elements of the vectors in order from the first element(s) to the last, and the value returned by `vector-for-each` is unspecified. If more than one vector is given and not all vectors have the same length, `vector-for-each` terminates when the shortest vector runs out. It is an error for procedure to mutate any of the vectors.

Next: Selecting Vector Components, Previous: Vectors, Up: Vectors   [Contents][Index]