NAME¶
ArrayLabels - Array operations.
Module¶
Module ArrayLabels
Documentation¶
Module
ArrayLabels
:
sig end
Array operations.
val length :
'a array -> int
Return the length (number of elements) of the given array.
val get :
'a array -> int -> 'a
Array.get a n returns the element number
n of array
a . The
first element has number 0. The last element has number
Array.length a -
1 . You can also write
a.(n) instead of
Array.get a n .
Raise
Invalid_argument index out of bounds if
n is outside the
range 0 to
(Array.length a - 1) .
val set :
'a array -> int -> 'a -> unit
Array.set a n x modifies array
a in place, replacing element
number
n with
x . You can also write
a.(n) <- x
instead of
Array.set a n x .
Raise
Invalid_argument index out of bounds if
n is outside the
range 0 to
Array.length a - 1 .
val make :
int -> 'a -> 'a array
Array.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.
Raise
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 .
val create :
int -> 'a -> 'a array
Deprecated.
Array.create is an alias for
ArrayLabels.make .
val init :
int -> f:(int -> 'a) -> 'a array
Array.init n f returns a fresh array of length
n , with element
number
i initialized to the result of
f i . In other terms,
Array.init n f tabulates the results of
f applied to the
integers
0 to
n-1 .
Raise
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 .
val make_matrix :
dimx:int -> dimy:int -> 'a -> 'a array
array
Array.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) .
Raise
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 .
val create_matrix :
dimx:int -> dimy:int -> 'a -> 'a array
array
Deprecated.
Array.create_matrix is an alias for
ArrayLabels.make_matrix .
val append :
'a array -> 'a array -> 'a array
Array.append v1 v2 returns a fresh array containing the concatenation of
the arrays
v1 and
v2 .
val concat :
'a array list -> 'a array
Same as
Array.append , but concatenates a list of arrays.
val sub :
'a array -> pos:int -> len:int -> 'a array
Array.sub a start len returns a fresh array of length
len ,
containing the elements number
start to
start + len - 1 of array
a .
Raise
Invalid_argument Array.sub if
start and
len do not
designate a valid subarray of
a ; that is, if
start < 0 , or
len < 0 , or
start + len > Array.length a .
val copy :
'a array -> 'a array
Array.copy a returns a copy of
a , that is, a fresh array
containing the same elements as
a .
val fill :
'a array -> pos:int -> len:int -> 'a ->
unit
Array.fill a ofs len x modifies the array
a in place, storing
x in elements number
ofs to
ofs + len - 1 .
Raise
Invalid_argument Array.fill if
ofs and
len do not
designate a valid subarray of
a .
val blit :
src:'a array -> src_pos:int -> dst:'a array ->
dst_pos:int -> len:int -> unit
Array.blit v1 o1 v2 o2 len copies
len elements from array
v1 , starting at element number
o1 , to array
v2 ,
starting at element number
o2 . It works correctly even if
v1
and
v2 are the same array, and the source and destination chunks
overlap.
Raise
Invalid_argument Array.blit if
o1 and
len do not
designate a valid subarray of
v1 , or if
o2 and
len do
not designate a valid subarray of
v2 .
val to_list :
'a array -> 'a list
Array.to_list a returns the list of all the elements of
a .
val of_list :
'a list -> 'a array
Array.of_list l returns a fresh array containing the elements of
l
.
val iter :
f:('a -> unit) -> 'a array -> unit
Array.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.(Array.length a -
1); () .
val map :
f:('a -> 'b) -> 'a array -> 'b array
Array.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.(Array.length a - 1) |] .
val iteri :
f:(int -> 'a -> unit) -> 'a array -> unit
Same as
ArrayLabels.iter , but the function is applied to the index of
the element as first argument, and the element itself as second argument.
val mapi :
f:(int -> 'a -> 'b) -> 'a array -> 'b array
Same as
ArrayLabels.map , but the function is applied to the index of the
element as first argument, and the element itself as second argument.
val fold_left :
f:('a -> 'b -> 'a) -> init:'a -> 'b array
-> 'a
Array.fold_left f x a computes
f (... (f (f x a.(0)) a.(1)) ...)
a.(n-1) , where
n is the length of the array
a .
val fold_right :
f:('b -> 'a -> 'a) -> 'b array -> init:'a
-> 'a
Array.fold_right f a x computes
f a.(0) (f a.(1) ( ... (f a.(n-1) x)
...)) , where
n is the length of the array
a .
=== Sorting ===
val sort :
cmp:('a -> 'a -> int) -> 'a array -> unit
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,
Pervasives.compare is a suitable comparison function, provided there
are no floating-point NaN values in the data. After calling
Array.sort
, the array is sorted in place in increasing order.
Array.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
Array.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
val stable_sort :
cmp:('a -> 'a -> int) -> 'a array ->
unit
Same as
ArrayLabels.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
ArrayLabels.sort .
val fast_sort :
cmp:('a -> 'a -> int) -> 'a array ->
unit
Same as
Array.sort or
Array.stable_sort , whichever is faster on
typical input.