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Module Bigarraymodule Bigarray:
Large, multi-dimensional, numerical arrays.
This module implements multi-dimensional arrays of integers and floating-point numbers, thereafter referred to as ``big arrays''. The implementation allows efficient sharing of large numerical arrays between Caml code and C or Fortran numerical libraries.
Concerning the naming conventions, users of this module are encouraged
to do Big arrays support all the Caml ad-hoc polymorphic operations:
Big arrays can contain elements of the following kinds:
type float32_elt
type float64_elt
type complex32_elt
type complex64_elt
type int8_signed_elt
type int8_unsigned_elt
type int16_signed_elt
type int16_unsigned_elt
type int_elt
type int32_elt
type int64_elt
type nativeint_elt
type (
To each element kind is associated a Caml type, which is
the type of Caml values that can be stored in the big array
or read back from it. This type is not necessarily the same
as the type of the array elements proper: for instance,
a big array whose elements are of kind
float32_elt contains
32-bit single precision floats, but reading or writing one of
its elements from Caml uses the Caml type float , which is
64-bit double precision floats.
The abstract type val float32 :
See
Bigarray.char .val float64 :
See
Bigarray.char .val complex32 :
See
Bigarray.char .val complex64 :
See
Bigarray.char .val int8_signed :
See
Bigarray.char .val int8_unsigned :
See
Bigarray.char .val int16_signed :
See
Bigarray.char .val int16_unsigned :
See
Bigarray.char .val int :
See
Bigarray.char .val int32 :
See
Bigarray.char .val int64 :
See
Bigarray.char .val nativeint :
See
Bigarray.char .val char :
As shown by the types of the values above,
big arrays of kind
float32_elt and float64_elt are
accessed using the Caml type float . Big arrays of complex kinds
complex32_elt , complex64_elt are accessed with the Caml type
Complex.t . Big arrays of
integer kinds are accessed using the smallest Caml integer
type large enough to represent the array elements:
int for 8- and 16-bit integer bigarrays, as well as Caml-integer
bigarrays; int32 for 32-bit integer bigarrays; int64
for 64-bit integer bigarrays; and nativeint for
platform-native integer bigarrays. Finally, big arrays of
kind int8_unsigned_elt can also be accessed as arrays of
characters instead of arrays of small integers, by using
the kind value char instead of int8_unsigned .
type c_layout
type fortran_layout
To facilitate interoperability with existing C and Fortran code,
this library supports two different memory layouts for big arrays,
one compatible with the C conventions,
the other compatible with the Fortran conventions.
In the C-style layout, array indices start at 0, and
multi-dimensional arrays are laid out in row-major format.
That is, for a two-dimensional array, all elements of
row 0 are contiguous in memory, followed by all elements of
row 1, etc. In other terms, the array elements at
In the Fortran-style layout, array indices start at 1, and
multi-dimensional arrays are laid out in column-major format.
That is, for a two-dimensional array, all elements of
column 0 are contiguous in memory, followed by all elements of
column 1, etc. In other terms, the array elements at
Each layout style is identified at the type level by the
abstract types type
The type
'a layout represents one of the two supported
memory layouts: C-style if 'a is Bigarray.c_layout , Fortran-style
if 'a is Bigarray.fortran_layout .
The abstract values val c_layout : val fortran_layout :
module Genarray:
module Array1:
One-dimensional arrays.
module Array2:
Two-dimensional arrays.
module Array3:
Three-dimensional arrays.
val genarray_of_array1 :
Return the generic big array corresponding to the given one-dimensional big array.
val genarray_of_array2 :
Return the generic big array corresponding to the given two-dimensional big array.
val genarray_of_array3 :
Return the generic big array corresponding to the given three-dimensional big array.
val array1_of_genarray :
Return the one-dimensional big array corresponding to the given
generic big array. Raise
Invalid_arg if the generic big array
does not have exactly one dimension.val array2_of_genarray :
Return the two-dimensional big array corresponding to the given
generic big array. Raise
Invalid_arg if the generic big array
does not have exactly two dimensions.val array3_of_genarray :
Return the three-dimensional big array corresponding to the given
generic big array. Raise
Invalid_arg if the generic big array
does not have exactly three dimensions.
val reshape : reshape b [|d1;...;dN|] converts the big array b to a
N -dimensional array of dimensions d1 ...dN . The returned
array and the original array b share their data
and have the same layout. For instance, assuming that b
is a one-dimensional array of dimension 12, reshape b [|3;4|]
returns a two-dimensional array b' of dimensions 3 and 4.
If b has C layout, the element (x,y) of b' corresponds
to the element x * 3 + y of b . If b has Fortran layout,
the element (x,y) of b' corresponds to the element
x + (y - 1) * 4 of b .
The returned big array must have exactly the same number of
elements as the original big array b . That is, the product
of the dimensions of b must be equal to i1 * ... * iN .
Otherwise, Invalid_arg is raised.val reshape_1 :
Specialized version of
Bigarray.reshape for reshaping to one-dimensional arrays.val reshape_2 :
Specialized version of
Bigarray.reshape for reshaping to two-dimensional arrays.val reshape_3 :
Specialized version of
Bigarray.reshape for reshaping to three-dimensional arrays. |