Bigarray(3)							   OCaml library						       Bigarray(3)

NAME

       Bigarray - Large, multi-dimensional, numerical arrays.

Module
       Module	Bigarray

Documentation
       Module Bigarray
	: sig end

       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 OCaml code and C or Fortran numerical libraries.

       Concerning the naming conventions, users of this module are encouraged to do open Bigarray in their source, then refer to array	types  and
       operations via short dot notation, e.g.	Array1.t or Array2.sub .

       Big arrays support all the OCaml ad-hoc polymorphic operations:

       -comparisons ( = , <> , <= , etc, as well as Pervasives.compare );

       -hashing (module Hash );

       -and structured input-output (the functions from the Marshal module, as well as Pervasives.output_value and Pervasives.input_value ).

       === Element kinds ===

       ===  Big  arrays  can  contain  elements  of  the  following  kinds:  -	IEEE  single  precision  (32  bits) floating-point numbers (Bigar-
       ray.float32_elt), - IEEE double precision (64 bits) floating-point numbers (Bigarray.float64_elt), - IEEE single precision (2  *  32  bits)
       floating-point  complex	numbers  (Bigarray.complex32_elt),  -  IEEE  double precision (2 * 64 bits) floating-point complex numbers (Bigar-
       ray.complex64_elt), - 8-bit integers (signed or unsigned)  (Bigarray.int8_signed_elt  or  Bigarray.int8_unsigned_elt),  -  16-bit  integers
       (signed or unsigned) (Bigarray.int16_signed_elt or Bigarray.int16_unsigned_elt), - OCaml integers (signed, 31 bits on 32-bit architectures,
       63 bits on 64-bit architectures) (Bigarray.int_elt), - 32-bit  signed  integer  (Bigarray.int32_elt),  -  64-bit  signed  integers  (Bigar-
       ray.int64_elt),	-  platform-native  signed  integers  (32  bits  on  32-bit  architectures,  64  bits  on  64-bit  architectures)  (Bigar-
       ray.nativeint_elt).  Each element kind is represented at the type level by one of the abstract types defined below. ===

       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 ('a, 'b) kind

       To each element kind is associated an OCaml type, which is the type of OCaml 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 OCaml uses	the  OCaml  type  float  ,
       which is 64-bit double precision floats.

       The  abstract  type ('a, 'b) kind captures this association of an OCaml type 'a for values read or written in the big array, and of an ele-
       ment kind 'b which represents the actual contents of the big array.  The following predefined values of type kind list all possible associ-
       ations of OCaml types with element kinds:

       val float32 : (float, float32_elt) kind

       See Bigarray.char .

       val float64 : (float, float64_elt) kind

       See Bigarray.char .

       val complex32 : (Complex.t, complex32_elt) kind

       See Bigarray.char .

       val complex64 : (Complex.t, complex64_elt) kind

       See Bigarray.char .

       val int8_signed : (int, int8_signed_elt) kind

       See Bigarray.char .

       val int8_unsigned : (int, int8_unsigned_elt) kind

       See Bigarray.char .

       val int16_signed : (int, int16_signed_elt) kind

       See Bigarray.char .

       val int16_unsigned : (int, int16_unsigned_elt) kind

       See Bigarray.char .

       val int : (int, int_elt) kind

       See Bigarray.char .

       val int32 : (int32, int32_elt) kind

       See Bigarray.char .

       val int64 : (int64, int64_elt) kind

       See Bigarray.char .

       val nativeint : (nativeint, nativeint_elt) kind

       See Bigarray.char .

       val char : (char, int8_unsigned_elt) kind

       As  shown  by  the types of the values above, big arrays of kind float32_elt and float64_elt are accessed using the OCaml type float .  Big
       arrays of complex kinds complex32_elt , complex64_elt are accessed with the OCaml type  Complex.t  .   Big  arrays  of  integer	kinds  are
       accessed  using	the  smallest OCaml integer type large enough to represent the array elements: int for 8- and 16-bit integer bigarrays, as
       well as OCaml-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 .

       === Array layouts ===

       type c_layout

       See Bigarray.fortran_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-dimen-
       sional 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 (x,y) and (x, y+1) are adjacent in memory.

       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 (x,y) and (x+1, y) are adjacent in memory.

       Each layout style is identified at the type level by the abstract types Bigarray.c_layout and fortran_layout respectively.

       type 'a layout

       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 Bigar-
       ray.fortran_layout .

       === Supported layouts The abstract values c_layout and fortran_layout represent the two supported layouts at the level of values. ===

       val c_layout : c_layout layout

       val fortran_layout : fortran_layout layout

       === Generic arrays (of arbitrarily many dimensions) ===

       module Genarray : sig end

       === One-dimensional arrays ===

       module Array1 : sig end

       One-dimensional arrays. The Array1 structure provides operations similar to those of Bigarray.Genarray , but specialized  to  the  case	of
       one-dimensional	arrays.   (The	Array2	and Array3 structures below provide operations specialized for two- and three-dimensional arrays.)
       Statically knowing the number of dimensions of the array allows faster operations, and more precise static type-checking.

       === Two-dimensional arrays ===

       module Array2 : sig end

       Two-dimensional arrays. The Array2 structure provides operations similar to those of Bigarray.Genarray , but specialized  to  the  case	of
       two-dimensional arrays.

       === Three-dimensional arrays ===

       module Array3 : sig end

       Three-dimensional  arrays.  The Array3 structure provides operations similar to those of Bigarray.Genarray , but specialized to the case of
       three-dimensional arrays.

       === Coercions between generic big arrays and fixed-dimension big arrays ===

       val genarray_of_array1 : ('a, 'b, 'c) Array1.t -> ('a, 'b, 'c) Genarray.t

       Return the generic big array corresponding to the given one-dimensional big array.

       val genarray_of_array2 : ('a, 'b, 'c) Array2.t -> ('a, 'b, 'c) Genarray.t

       Return the generic big array corresponding to the given two-dimensional big array.

       val genarray_of_array3 : ('a, 'b, 'c) Array3.t -> ('a, 'b, 'c) Genarray.t

       Return the generic big array corresponding to the given three-dimensional big array.

       val array1_of_genarray : ('a, 'b, 'c) Genarray.t -> ('a, 'b, 'c) Array1.t

       Return the one-dimensional big array corresponding to the given generic big array.  Raise Invalid_argument if the generic  big  array  does
       not have exactly one dimension.

       val array2_of_genarray : ('a, 'b, 'c) Genarray.t -> ('a, 'b, 'c) Array2.t

       Return  the  two-dimensional  big array corresponding to the given generic big array.  Raise Invalid_argument if the generic big array does
       not have exactly two dimensions.

       val array3_of_genarray : ('a, 'b, 'c) Genarray.t -> ('a, 'b, 'c) Array3.t

       Return the three-dimensional big array corresponding to the given generic big array.  Raise Invalid_argument if the generic big array  does
       not have exactly three dimensions.

       === Re-shaping big arrays ===

       val reshape : ('a, 'b, 'c) Genarray.t -> int array -> ('a, 'b, 'c) Genarray.t

       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_argument is raised.

       val reshape_1 : ('a, 'b, 'c) Genarray.t -> int -> ('a, 'b, 'c) Array1.t

       Specialized version of Bigarray.reshape for reshaping to one-dimensional arrays.

       val reshape_2 : ('a, 'b, 'c) Genarray.t -> int -> int -> ('a, 'b, 'c) Array2.t

       Specialized version of Bigarray.reshape for reshaping to two-dimensional arrays.

       val reshape_3 : ('a, 'b, 'c) Genarray.t -> int -> int -> int -> ('a, 'b, 'c) Array3.t

       Specialized version of Bigarray.reshape for reshaping to three-dimensional arrays.

OCamldoc							    2014-06-09							       Bigarray(3)