Mercurial > octave
view scripts/io/textread.m @ 22489:93ea313301f9
test: Add bug ids (<#####>) to BIST tests.
* bsxfun.cc, cellfun.cc, conv2.cc, data.cc, ellipj.cc, error.cc, file-io.cc,
graphics.cc, hash.cc, mappers.cc, max.cc, rand.cc, regexp.cc, symtab.cc,
chol.cc, gzip.cc, symbfact.cc, ov-cx-diag.cc, ov-fcn-handle.cc, ov-java.cc,
Sparse.cc, accumarray.m, bitset.m, fieldnames.m, inputParser.m, interp2.m,
interpft.m, num2str.m, postpad.m, prepad.m, rat.m, rectint.m, image.m,
imread.m, imwrite.m, importdata.m, strread.m, textread.m, orderfields.m, qp.m,
axis.m, legend.m, hist.m, residue.m, setdiff.m, fftshift.m, ifftshift.m,
nthroot.m, magic.m, median.m, quantile.m, base2dec.m, strsplit.m, datestr.m,
datevec.m:
test: Add bug ids (<#####>) to BIST tests.
author | Rik <rik@octave.org> |
---|---|
date | Wed, 14 Sep 2016 16:05:16 -0700 |
parents | 119f408f2dd1 |
children | 3a2b891d0b33 e9a0469dedd9 |
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## Copyright (C) 2009-2016 Eric Chassande-Mottin, CNRS (France) ## ## This file is part of Octave. ## ## Octave is free software; you can redistribute it and/or modify it ## under the terms of the GNU General Public License as published by ## the Free Software Foundation; either version 3 of the License, or (at ## your option) any later version. ## ## Octave is distributed in the hope that it will be useful, but ## WITHOUT ANY WARRANTY; without even the implied warranty of ## MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the GNU ## General Public License for more details. ## ## You should have received a copy of the GNU General Public License ## along with Octave; see the file COPYING. If not, see ## <http://www.gnu.org/licenses/>. ## -*- texinfo -*- ## @deftypefn {} {[@var{a}, @dots{}] =} textread (@var{filename}) ## @deftypefnx {} {[@var{a}, @dots{}] =} textread (@var{filename}, @var{format}) ## @deftypefnx {} {[@var{a}, @dots{}] =} textread (@var{filename}, @var{format}, @var{n}) ## @deftypefnx {} {[@var{a}, @dots{}] =} textread (@var{filename}, @var{format}, @var{prop1}, @var{value1}, @dots{}) ## @deftypefnx {} {[@var{a}, @dots{}] =} textread (@var{filename}, @var{format}, @var{n}, @var{prop1}, @var{value1}, @dots{}) ## Read data from a text file. ## ## The file @var{filename} is read and parsed according to @var{format}. The ## function behaves like @code{strread} except it works by parsing a file ## instead of a string. See the documentation of @code{strread} for details. ## ## In addition to the options supported by @code{strread}, this function ## supports two more: ## ## @itemize ## @item @qcode{"headerlines"}: ## The first @var{value} number of lines of @var{filename} are skipped. ## ## @item @qcode{"endofline"}: ## Specify a single character or ## @qcode{"@xbackslashchar{}r@xbackslashchar{}n"}. If no value is given, it ## will be inferred from the file. If set to @qcode{""} (empty string) EOLs ## are ignored as delimiters. ## @end itemize ## ## The optional input @var{n} (format repeat count) specifies the number of ## times the format string is to be used or the number of lines to be read, ## whichever happens first while reading. The former is equivalent to ## requesting that the data output vectors should be of length @var{N}. ## Note that when reading files with format strings referring to multiple ## lines, @var{n} should rather be the number of lines to be read than the ## number of format string uses. ## ## If the format string is empty (not just omitted) and the file contains only ## numeric data (excluding headerlines), textread will return a rectangular ## matrix with the number of columns matching the number of numeric fields on ## the first data line of the file. Empty fields are returned as zero values. ## ## Examples: ## ## @example ## @group ## Assume a data file like: ## 1 a 2 b ## 3 c 4 d ## 5 e ## @end group ## @end example ## ## @example ## @group ## [a, b] = textread (f, "%f %s") ## returns two columns of data, one with doubles, the other a ## cellstr array: ## a = [1; 2; 3; 4; 5] ## b = @{"a"; "b"; "c"; "d"; "e"@} ## @end group ## @end example ## ## @example ## @group ## [a, b] = textread (f, "%f %s", 3) ## (read data into two culumns, try to use the format string ## three times) ## returns ## a = [1; 2; 3] ## b = @{"a"; "b"; "c"@} ## ## @end group ## @end example ## ## @example ## @group ## With a data file like: ## 1 ## a ## 2 ## b ## ## [a, b] = textread (f, "%f %s", 2) ## returns a = 1 and b = @{"a"@}; i.e., the format string is used ## only once because the format string refers to 2 lines of the ## data file. To obtain 2x1 data output columns, specify N = 4 ## (number of data lines containing all requested data) rather ## than 2. ## @end group ## @end example ## ## @seealso{strread, load, dlmread, fscanf, textscan} ## @end deftypefn function varargout = textread (filename, format = "%f", varargin) BUFLENGTH = 4096; # Read buffer to speed up processing @var{n} ## Check input if (nargin < 1) print_usage (); endif if (! ischar (filename) || ! ischar (format)) error ("textread: FILENAME and FORMAT arguments must be strings"); endif if (! isempty (varargin) && isnumeric (varargin{1})) nlines = varargin{1}; else nlines = Inf; endif if (nlines < 1) printf ("textread: N = 0, no data read\n"); varargout = cell (1, nargout); return; endif ## Read file fid = fopen (filename, "r"); if (fid == -1) error ("textread: could not open '%s' for reading", filename); endif ## Skip header lines if requested headerlines = find (strcmpi (varargin, "headerlines"), 1); if (! isempty (headerlines)) ## Beware of missing or wrong headerline value if (headerlines == numel (varargin) || ! isnumeric (varargin{headerlines + 1})) error ("textread: missing or invalid value for 'headerlines'" ); endif ## Avoid conveying floats to fskipl varargin{headerlines + 1} = round (varargin{headerlines + 1}); ## Beware of zero valued headerline, fskipl would skip to EOF if (varargin{headerlines + 1} > 0) fskipl (fid, varargin{headerlines + 1}); elseif (varargin{headerlines + 1} < 0) warning ("textread: negative headerline value ignored"); endif varargin(headerlines:headerlines+1) = []; endif st_pos = ftell (fid); ## Read a first file chunk. Rest follows after endofline processing [str, count] = fscanf (fid, "%c", BUFLENGTH); if (isempty (str) || count < 1) warning ("textread: empty file"); varargout = cell (1, nargout); return; endif endofline = find (strcmpi (varargin, "endofline"), 1); if (! isempty (endofline)) ## 'endofline' option set by user. if (ischar (varargin{endofline + 1})) eol_char = varargin{endofline + 1}; if (strcmp (typeinfo (eol_char), "sq_string")) eol_char = do_string_escapes (eol_char); endif if (! any (strcmp (eol_char, {"", "\n", "\r", "\r\n"}))) error ("textread: invalid EndOfLine character value specified"); endif else error ("textread: character value required for EndOfLine"); endif else ## Determine EOL from file. ## Search for EOL candidates in the first BUFLENGTH chars ## FIXME: Ignore risk of 2-byte EOL (\r\n) being split at exactly BUFLENGTH eol_srch_len = min (length (str), BUFLENGTH); ## First try DOS (CRLF) if (! isempty (strfind (str(1 : eol_srch_len), "\r\n"))) eol_char = "\r\n"; ## Perhaps old Macintosh? (CR) elseif (! isempty (strfind (str(1 : eol_srch_len), "\r"))) eol_char = "\r"; ## Otherwise, use plain *nix (LF) else eol_char = "\n"; endif ## Set up default endofline param value varargin(end+1:end+2) = {"endofline", eol_char}; endif ## Now that we know what EOL looks like, we can process format_repeat_count. ## FIXME: The below isn't ML-compatible: counts lines, not format string uses if (isfinite (nlines) && (nlines > 0)) l_eol_char = length (eol_char); eoi = findstr (str, eol_char); n_eoi = length (eoi); nblks = 0; ## Avoid slow repeated str concatenation, first seek requested end of data while (n_eoi < nlines && count == BUFLENGTH) [nstr, count] = fscanf (fid, "%c", BUFLENGTH); if (count > 0) ## Watch out for multichar EOL being missed across buffer boundaries if (l_eol_char > 1) str = [str(end - length (eol_char) + 2 : end) nstr]; else str = nstr; endif eoi = findstr (str, eol_char); n_eoi += numel (eoi); ++nblks; endif endwhile ## Handle case of missing or incomplete trailing EOL if (! strcmp (str(end - length (eol_char) + 1 : end), eol_char)) eoi = [ eoi (length (str)) ]; ++n_eoi; endif ## Found EOL delimiting last requested line. Compute ptr (incl. EOL) if (isempty (eoi)) eoi_pos = nblks * BUFLENGTH + count; else eoi_pos = (nblks * BUFLENGTH) + eoi(end + min (nlines, n_eoi) - n_eoi); endif fseek (fid, st_pos, "bof"); str = fscanf (fid, "%c", eoi_pos); else fseek (fid, st_pos, "bof"); str = fread (fid, "char=>char").'; endif fclose (fid); ## Set up default whitespace param value if needed if (isempty (find (strcmpi ("whitespace", varargin)))) varargin(end+1:end+2) = {"whitespace", " \b\t"}; endif ## Call strread to make it do the real work [varargout{1:max (nargout, 1)}] = strread (str, format, varargin{:}); ## Hack to concatenate/reshape numeric output into 2D array (undocumented ML) ## In ML this only works in case of an empty format string if (isempty (format)) ## Get number of fields per line. ## 1. Get eol_char position iwhsp = find (strcmpi ("whitespace", varargin)); whsp = varargin{iwhsp + 1}; idx = regexp (str, eol_char, "once"); ## 2. Get first data line til EOL. Avoid corner case of just one line if (! isempty (idx)) str = str(1:idx-1); endif idelimiter = find (strcmpi (varargin, "delimiter"), 1); if (isempty (idelimiter)) ## Assume delimiter = whitespace ## 3A. whitespace incl. consecutive whitespace => single space str = regexprep (str, sprintf ("[%s]+", whsp), ' '); ## 4A. Remove possible leading & trailing spaces str = strtrim (str); ## 5A. Count spaces, add one to get nr of data fields per line ncols = numel (strfind (str, " ")) + 1; else ## 3B. Just count delimiters. FIXME: delimiters could occur in literals delimiter = varargin{idelimiter+1}; ncols = numel (regexp (str, sprintf ("[%s]", delimiter))) + 1; endif ## 6. Reshape; watch out, we need a transpose nrows = ceil (numel (varargout{1}) / ncols); pad = mod (numel (varargout{1}), ncols); if (pad > 0) pad = ncols - pad; varargout{1}(end+1 : end+pad) = NaN; endif varargout{1} = reshape (varargout{1}, ncols, nrows)'; ## ML replaces empty values with NaNs varargout{1}(find (isnan (varargout{1}))) = 0; endif endfunction %!test %! f = tempname (); %! d = rand (5, 3); %! dlmwrite (f, d, "precision", "%5.2f"); %! [a, b, c] = textread (f, "%f %f %f", "delimiter", ",", "headerlines", 3); %! unlink (f); %! assert (a, d(4:5, 1), 1e-2); %! assert (b, d(4:5, 2), 1e-2); %! assert (c, d(4:5, 3), 1e-2); %!test %! f = tempname (); %! d = rand (7, 2); %! dlmwrite (f, d, "precision", "%5.2f"); %! [a, b] = textread (f, "%f, %f", "headerlines", 1); %! unlink (f); %! assert (a, d(2:7, 1), 1e-2); ## Test reading 2D matrix with empty format %!test %! f = tempname (); %! d = rand (5, 2); %! dlmwrite (f, d, "precision", "%5.2f"); %! A = textread (f, "", "headerlines", 3); %! unlink (f); %! assert (A, d(4:5, :), 1e-2); ## Read multiple lines using empty format string %!test %! f = tempname (); %! unlink (f); %! fid = fopen (f, "w"); %! d = rand (1, 4); %! fprintf (fid, " %f %f %f %f ", d); %! fclose (fid); %! A = textread (f, ""); %! unlink (f); %! assert (A, d, 1e-6); ## Empty format, corner case = one line w/o EOL %!test %! f = tempname (); %! unlink (f); %! fid = fopen (f, "w"); %! d = rand (1, 4); %! fprintf (fid, " %f %f %f %f ", d); %! fclose (fid); %! A = textread (f, ""); %! unlink (f); %! assert (A, d, 1e-6); ## Tests with format repeat count #1 %!test %! f = tempname (); %! fid = fopen (f, "w"); %! fprintf (fid, "%2d %s %2d %s\n %2d %s %2d %s \n", ... %! 10, "a", 20, "b", 30, "c", 40, "d"); %! fclose (fid); %! [a, b] = textread (f, "%d %s", 1); %! assert (a, int32 (10)); %! assert (b, {"a"}); %! [a, b] = textread (f, "%d %s", 2); %! assert (a, int32 ([10; 20])); %! assert (b, {"a"; "b"}); %! [a, b] = textread (f, "%d %s", 3); %! assert (a, int32 ([10; 20; 30])); %! assert (b, {"a"; "b"; "c"}); %! [a, b] = textread (f, "%d %s", 4); %! assert (a, int32 ([10; 20; 30; 40])); %! assert (b, {"a"; "b"; "c"; "d"}); %! [a, b] = textread (f, "%d %s", 5); %! assert (a, int32 ([10; 20; 30; 40])); %! assert (b, {"a"; "b"; "c"; "d"}); %! unlink (f); ## Tests with format repeat count #2, missing last EOL %!test %! f = tempname (); %! fid = fopen (f, "w"); %! fprintf (fid, "%2d %s %2d %s\n %2d %s %2d %s", ... %! 10, "a", 20, "b", 30, "c", 40, "d"); %! fclose (fid); %! [a, b] = textread (f, "%d %s", 1); %! assert (a, int32 (10)); %! assert (b, {"a"}); %! [a, b] = textread (f, "%d %s", 2); %! assert (a, int32 ([10; 20])); %! assert (b, {"a"; "b"}); %! [a, b] = textread (f, "%d %s", 3); %! assert (a, int32 ([10; 20; 30])); %! assert (b, {"a"; "b"; "c"}); %! [a, b] = textread (f, "%d %s", 4); %! assert (a, int32 ([10; 20; 30; 40])); %! assert (b, {"a"; "b"; "c"; "d"}); %! [a, b] = textread (f, "%d %s", 5); %! assert (a, int32 ([10; 20; 30; 40])); %! assert (b, {"a"; "b"; "c"; "d"}); %! unlink (f); ## Tests with format repeat count #3, incomplete last line %!test %! f = tempname (); %! fid = fopen (f, "w"); %! fprintf (fid, "%2d %s %2d %s\n %2d %s %2d", ... %! 10, "a", 20, "b", 30, "c", 40); %! fclose (fid); %! [a, b] = textread (f, "%d %s", 1); %! assert (a, int32 (10)); %! assert (b, {"a"}); %! [a, b] = textread (f, "%d %s", 2); %! assert (a, int32 ([10; 20])); %! assert (b, {"a"; "b"}); %! [a, b] = textread (f, "%d %s", 3); %! assert (a, int32 ([10; 20; 30])); %! assert (b, {"a"; "b"; "c"}); %! [a, b] = textread (f, "%d %s", 4); %! assert (a, int32 ([10; 20; 30; 40])); %! assert (b, {"a"; "b"; "c"}); %! [a, b] = textread (f, "%d %s", 5); %! assert (a, int32 ([10; 20; 30; 40])); %! assert (b, {"a"; "b"; "c"}); %! unlink (f); ## Tests with format repeat count #4, incomplete last line but with trailing EOL %!test %! f = tempname (); %! fid = fopen (f, "w"); %! fprintf (fid, "%2d %s %2d %s\n %2d %s %2d\n", ... %! 10, "a", 20, "b", 30, "c", 40); %! fclose (fid); %! [a, b] = textread (f, "%d %s", 4); %! assert (a, int32 ([10; 20; 30; 40])); %! assert (b, {"a"; "b"; "c"; ""}); %! [a, b] = textread (f, "%d %s", 5); %! assert (a, int32 ([10; 20; 30; 40])); %! assert (b, {"a"; "b"; "c"; ""}); %! unlink (f); ### Tests with format repeat count #5, nr of data lines = limiting factor #%!test #%! f = tempname (); #%! fid = fopen (f, "w"); #%! fprintf (fid, "%2d\n%s\n%2dn%s", ... #%! 1, "a", 2, "b"); #%! fclose (fid); #%! [a, b] = textread (f, "%d %s", 2); #%! assert (a, int32 (1)); #%! assert (b, {"a"}); ### Read multiple lines using empty format string, missing data (should be 0) #%!test #%! f = tempname (); #%! unlink (f); #%! fid = fopen (f, "w"); #%! d = rand (1, 4); #%! fprintf (fid, "%f, %f, , %f, %f ", d); #%! fclose (fid); #%! A = textread (f, ""); #%! unlink (f); #%! assert (A, [ d(1:2) 0 d(3:4)], 1e-6); ### Test with empty positions - ML returns 0 for empty fields #%!test #%! f = tempname (); #%! unlink (f); #%! fid = fopen (f, "w"); #%! d = rand (1, 4); #%! fprintf (fid, ",2,,4\n5,,7,\n"); #%! fclose (fid); #%! A = textread (f, "", "delimiter", ","); #%! unlink (f); #%! assert (A, [0 2 0 4; 5 0 7 0], 1e-6); ### Another test with empty format + positions, now with more incomplete lower ### row (must be appended with zeros to get rectangular matrix) #%!test #%! f = tempname (); #%! unlink (f); #%! fid = fopen (f, "w"); #%! d = rand (1, 4); #%! fprintf (fid, ",2,,4\n5,\n"); #%! fclose (fid); #%! A = textread (f, "", "delimiter", ","); #%! unlink (f); #%! assert (A, [0 2 0 4; 5 0 0 0], 1e-6); ### Test endofline #%!test <45046> #%! f = tempname (); #%! fid = fopen (f, "w"); #%! fprintf (fid, "a\rb\rc"); #%! fclose (fid); #%! ## Test EOL detection #%! d = textread (f, "%s"); #%! assert (d, {"a";"b";"c"}); #%! ## Test explicit EOL specification (bug #45046) #%! d = textread (f, "%s", "endofline", "\r"); #%! assert (d, {"a"; "b"; "c"}); #%! unlink (f); ### Properly process single-quoted EOL args #%!test <46477> #%! f = tempname (); #%! fid = fopen (f, "w"); #%! fprintf (fid, "hello, world!"); #%! fclose (fid); #%! [a, b] = textread (f, "%s%s", "endofline", '\n'); #%! assert (a{1}, "hello,"); #%! assert (b{1}, "world!"); ### Test input validation #%!error textread () #%!error textread (1) #%!error <arguments must be strings> textread (1, "%f") #%!error <arguments must be strings> textread ("fname", 1) #%!error <missing or invalid value for> textread (file_in_loadpath ("textread.m"), "", "headerlines") #%!error <missing or invalid value for> textread (file_in_loadpath ("textread.m"), "", "headerlines", 'hh') #%!error <character value required for> textread (file_in_loadpath ("textread.m"), "%s", "endofline", true)