Module Stdlib.ArrayLabels

An alias for the type of arrays.

Return the length (number of elements) of the given array.

get a n returns the element number n of array a. The first element has number 0. The last element has number length a - 1. You can also write a.(n) instead of get a n.

raises Invalid_argument

if n is outside the range 0 to (length a - 1).

set a n x modifies array a in place, replacing element number n with x. You can also write a.(n) <- x instead of set a n x.

raises Invalid_argument

if n is outside the range 0 to length a - 1.

make n x returns a fresh array of length n, initialized with x. All the elements of this new array are initially physically equal to x (in the sense of the == predicate). Consequently, if x is mutable, it is shared among all elements of the array, and modifying x through one of the array entries will modify all other entries at the same time.

raises Invalid_argument

if n < 0 or n > Sys.max_array_length. If the value of x is a floating-point number, then the maximum size is only Sys.max_array_length / 2.

deprecated

create is an alias for make.

init n ~f returns a fresh array of length n, with element number i initialized to the result of f i. In other terms, init n ~f tabulates the results of f applied to the integers 0 to n-1.

raises Invalid_argument

if n < 0 or n > Sys.max_array_length. If the return type of f is float, then the maximum size is only Sys.max_array_length / 2.

make_matrix ~dimx ~dimy e returns a two-dimensional array (an array of arrays) with first dimension dimx and second dimension dimy. All the elements of this new matrix are initially physically equal to e. The element (x,y) of a matrix m is accessed with the notation m.(x).(y).

raises Invalid_argument

if dimx or dimy is negative or greater than Sys.max_array_length. If the value of e is a floating-point number, then the maximum size is only Sys.max_array_length / 2.

deprecated

create_matrix is an alias for make_matrix.

append v1 v2 returns a fresh array containing the concatenation of the arrays v1 and v2.

Same as append, but concatenates a list of arrays.

sub a ~pos ~len returns a fresh array of length len, containing the elements number pos to pos + len - 1 of array a.

raises Invalid_argument

if pos and len do not designate a valid subarray of a; that is, if pos < 0, or len < 0, or pos + len > length a.

copy a returns a copy of a, that is, a fresh array containing the same elements as a.

fill a ~pos ~len x modifies the array a in place, storing x in elements number pos to pos + len - 1.

raises Invalid_argument

if pos and len do not designate a valid subarray of a.

blit ~src ~src_pos ~dst ~dst_pos ~len copies len elements from array src, starting at element number src_pos, to array dst, starting at element number dst_pos. It works correctly even if src and dst are the same array, and the source and destination chunks overlap.

raises Invalid_argument

if src_pos and len do not designate a valid subarray of src, or if dst_pos and len do not designate a valid subarray of dst.

to_list a returns the list of all the elements of a.

of_list l returns a fresh array containing the elements of l.

iter ~f a applies function f in turn to all the elements of a. It is equivalent to f a.(0); f a.(1); ...; f a.(length a - 1); ().

map ~f a applies function f to all the elements of a, and builds an array with the results returned by f: [| f a.(0); f a.(1); ...; f a.(length a - 1) |].

Same as iter, but the function is applied to the index of the element as first argument, and the element itself as second argument.

Same as map, but the function is applied to the index of the element as first argument, and the element itself as second argument.

fold_left ~f ~init a computes f (... (f (f init a.(0)) a.(1)) ...) a.(n-1), where n is the length of the array a.

fold_right ~f a ~init computes f a.(0) (f a.(1) ( ... (f a.(n-1) init) ...)), where n is the length of the array a.

iter2 ~f a b applies function f to all the elements of a and b.

raises Invalid_argument

if the arrays are not the same size.

since

4.05.0

map2 ~f a b applies function f to all the elements of a and b, and builds an array with the results returned by f: [| f a.(0) b.(0); ...; f a.(length a - 1) b.(length b - 1)|].

raises Invalid_argument

if the arrays are not the same size.

since

4.05.0

exists ~f [|a1; ...; an|] checks if at least one element of the array satisfies the predicate f. That is, it returns (f a1) || (f a2) || ... || (f an).

since

4.03.0

for_all ~f [|a1; ...; an|] checks if all elements of the array satisfy the predicate f. That is, it returns (f a1) && (f a2) && ... && (f an).

since

4.03.0

Same as ArrayLabels.for_all, but for a two-argument predicate.

raises Invalid_argument

if the two arrays have different lengths.

since

4.11.0

Same as ArrayLabels.exists, but for a two-argument predicate.

raises Invalid_argument

if the two arrays have different lengths.

since

4.11.0

mem x ~set is true if and only if x is equal to an element of set.

since

4.03.0

Same as mem, but uses physical equality instead of structural equality to compare list elements.

since

4.03.0

create_float n returns a fresh float array of length n, with uninitialized data.

since

4.03

deprecated

make_float is an alias for create_float.

Sort an array in increasing order according to a comparison function. The comparison function must return 0 if its arguments compare as equal, a positive integer if the first is greater, and a negative integer if the first is smaller (see below for a complete specification). For example, Stdlib.compare is a suitable comparison function, provided there are no floating-point NaN values in the data. After calling sort, the array is sorted in place in increasing order. sort is guaranteed to run in constant heap space and (at most) logarithmic stack space.

The current implementation uses Heap Sort. It runs in constant stack space.

Specification of the comparison function: Let a be the array and cmp the comparison function. The following must be true for all x, y, z in a :

• cmp x y > 0 if and only if cmp y x < 0
• if cmp x y >= 0 and cmp y z >= 0 then cmp x z >= 0

When sort returns, a contains the same elements as before, reordered in such a way that for all i and j valid indices of a :

• cmp a.(i) a.(j) >= 0 if and only if i >= j

Same as sort, but the sorting algorithm is stable (i.e. elements that compare equal are kept in their original order) and not guaranteed to run in constant heap space.

The current implementation uses Merge Sort. It uses n/2 words of heap space, where n is the length of the array. It is usually faster than the current implementation of sort.

Same as sort or stable_sort, whichever is faster on typical input.

Iterate on the array, in increasing order

since

4.07

Iterate on the array, in increasing order, yielding indices along elements

since

4.07

Create an array from the generator

since

4.07