numericalio

`assume_external_byte_order` (byte_order_flag) — Function

Tells numericalio the byte order for reading and writing binary data. Two values of byte_order_flag are recognized: lsb which indicates least-significant byte first, also called little-endian byte order; and msb which indicates most-significant byte first, also called big-endian byte order.

If not specified, numericalio assumes the external byte order is most-significant byte first.

`opena_binary` (file_name) — Function

Returns an output stream of 8-bit unsigned bytes to append the file named by file_name.

`openr_binary` (file_name) — Function

Returns an input stream of 8-bit unsigned bytes to read the file named by file_name.

`openw_binary` (file_name) — Function

Returns an output stream of 8-bit unsigned bytes to write the file named by file_name.

See also openr_binary, opena_binary and openw.

See also: openr_binary, opena_binary, openw.

`read_array` (S, A) — Function

Reads the source S into the array A, until A is full or the source is exhausted. Input data are read into the array in row-major order; the input need not conform to the dimensions of A.

The source S may be a file name or a stream.

The recognized values of separator_flag are comma, pipe, semicolon, and space. Equivalently, the separator may be specified as a string of one character: "," (comma), "|" (pipe), ";" (semicolon), " " (space), or " " (tab). If separator_flag is not specified, the file is assumed space-delimited.

See also openr, read_matrix, read_hashed_array, read_list, read_binary_array and read_005fnested_005flist.

See also: openr, read_matrix, read_hashed_array, read_list, read_binary_array, read_nested_list.

`read_binary_array` (S, A) — Function

Reads binary 8-byte floating point numbers from the source S into the array A until A is full, or the source is exhausted. A must be an array created by array or make_array. Elements of A are read in row-major order.

The source S may be a file name or a stream.

The byte order in elements of the source is specified by assume_external_byte_order.

`read_binary_list` (S) — Function

read_binary_list(S) reads the entire content of the source S as a sequence of binary 8-byte floating point numbers, and returns it as a list. The source S may be a file name or a stream.

read_binary_list(S, L) reads 8-byte binary floating point numbers from the source S until the list L is full, or the source is exhausted.

The byte order in elements of the source is specified by assume_external_byte_order.

`read_binary_matrix` (S, M) — Function

Reads binary 8-byte floating point numbers from the source S into the matrix M until M is full, or the source is exhausted. Elements of M are read in row-major order.

The source S may be a file name or a stream.

The byte order in elements of the source is specified by assume_external_byte_order.

`read_hashed_array` (S, A) — Function

Reads the source S and returns its entire content as a hashed-array. The source S may be a file name or a stream.

read_hashed_array treats the first item on each line as a hash key, and associates the remainder of the line (as a list) with the key. For example, the line 567 12 17 32 55 is equivalent to A[567]: [12, 17, 32, 55]$. Lines need not have the same numbers of elements.

See also openr, read_matrix, read_array, read_list and read_005fnested_005flist.

See also: hashed-array, openr, read_matrix, read_array, read_list, read_nested_list.

`read_list` (S) — Function

read_list(S) reads the source S and returns its entire content as a flat list.

read_list(S, L) reads the source S into the list L, until L is full or the source is exhausted.

The source S may be a file name or a stream.

See also openr, read_matrix, read_array, read_nested_list, read_binary_list and read_005fhashed_005farray.

See also: openr, read_matrix, read_array, read_nested_list, read_binary_list, read_hashed_array.

`read_matrix` (S) — Function

read_matrix(S) reads the source S and returns its entire content as a matrix. The size of the matrix is inferred from the input data; each line of the file becomes one row of the matrix. If some lines have different lengths, read_matrix complains.

read_matrix(S, M) read the source S into the matrix M, until M is full or the source is exhausted. Input data are read into the matrix in row-major order; the input need not have the same number of rows and columns as M.

The source S may be a file name or a stream which for example allows skipping the very first line of a file (that may be useful, if you read CSV data, where the first line often contains the description of the columns):

s : openr("data.txt");
readline(s);  /* skip the first line */
M : read_matrix(s, 'comma);  /* read the following (comma-separated) lines into matrix M */
close(s);

See also openr, read_array, read_hashed_array, read_list, read_binary_matrix, write_data and read_005fnested_005flist.

See also: openr, read_array, read_hashed_array, read_list, read_binary_matrix, write_data, read_nested_list.

`read_nested_list` (S) — Function

Reads the source S and returns its entire content as a nested list. The source S may be a file name or a stream.

read_nested_list returns a list which has a sublist for each line of input. Lines need not have the same numbers of elements. Empty lines are not ignored: an empty line yields an empty sublist.

See also openr, read_matrix, read_array, read_list and read_005fhashed_005farray.

See also: openr, read_matrix, read_array, read_list, read_hashed_array.

`write_binary_data` (X, D) — Function

Writes the object X, comprising binary 8-byte IEEE 754 floating-point numbers, to the destination D. Other kinds of numbers are coerced to 8-byte floats. write_binary_data cannot write non-numeric data.

The object X may be a list, a nested list, a matrix, or an array created by array or make_array; X cannot be a hashed array or any other type of object. write_binary_data writes nested lists, matrices, and arrays in row-major order.

The destination D may be a file name or a stream. When the destination is a file name, the global variable file_output_append governs whether the output file is appended or truncated. When the destination is a stream, no special action is taken by write_binary_data after all the data are written; in particular, the stream remains open.

The byte order in elements of the destination is specified by assume_external_byte_order.

`write_data` (X, D) — Function

Writes the object X to the destination D.

write_data writes a matrix in row-major order, with one line per row.

write_data writes an array created by array or make_array in row-major order, with a new line at the end of every slab. Higher-dimensional slabs are separated by additional new lines.

write_data writes a hashed array with each key followed by its associated list on one line.

write_data writes a nested list with each sublist on one line.

write_data writes a flat list all on one line.

The destination D may be a file name or a stream. When the destination is a file name, the global variable file_output_append governs whether the output file is appended or truncated. When the destination is a stream, no special action is taken by write_data after all the data are written; in particular, the stream remains open.

The recognized values of separator_flag are comma, pipe, semicolon, space, and tab. Equivalently, the separator may be specified as a string of one character: "," (comma), "|" (pipe), ";" (semicolon), " " (space), or " " (tab). If separator_flag is not specified, the file is assumed space-delimited.

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