Construction of Vectors (MIT/GNU Scheme 12.1)

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### 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.

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