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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);
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_array, read_hashed_array,
read_list, read_binary_matrix, write_data and
read_nested_list.
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_nested_list.
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.
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_array,
read_list and read_nested_list.
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.
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_array,
read_list and read_hashed_array.
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.
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_array,
read_nested_list, read_binary_list and read_hashed_array.
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.
See also openw and read_matrix.
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