Mercurial > hg > octave-lyh
annotate scripts/io/textscan.m @ 12679:f38cf6224452 stable
Fix textscan/textread headerlines arg always skipping 2 lines (bug #33028)
* textread.m, textscan.m: Fix wrong headerline argument being fed
to fskipl. Check & avoid processing zero headerline values.
| author | Philip Nienhuis <prnienhuis@users.sf.net> |
|---|---|
| date | Sun, 15 May 2011 19:15:50 -0700 |
| parents | d0b799dafede |
| children | fe6e2afcd9ee |
| rev | line source |
|---|---|
| 11523 | 1 ## Copyright (C) 2010-2011 Ben Abbott <bpabbott@mac.com> |
| 11141 | 2 ## |
| 3 ## This file is part of Octave. | |
| 4 ## | |
| 5 ## Octave is free software; you can redistribute it and/or modify it | |
| 6 ## under the terms of the GNU General Public License as published by | |
| 7 ## the Free Software Foundation; either version 3 of the License, or (at | |
| 8 ## your option) any later version. | |
| 9 ## | |
| 10 ## Octave is distributed in the hope that it will be useful, but | |
| 11 ## WITHOUT ANY WARRANTY; without even the implied warranty of | |
| 12 ## MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the GNU | |
| 13 ## General Public License for more details. | |
| 14 ## | |
| 15 ## You should have received a copy of the GNU General Public License | |
| 16 ## along with Octave; see the file COPYING. If not, see | |
| 17 ## <http://www.gnu.org/licenses/>. | |
| 18 | |
| 19 ## -*- texinfo -*- | |
|
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Use uppercase 'A' to refer to matrix inputs in m-files.
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20 ## @deftypefn {Function File} {@var{C} =} textscan (@var{fid}, @var{format}) |
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Grammarcheck files for 3.4.1 release.
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21 ## @deftypefnx {Function File} {@var{C} =} textscan (@var{fid}, @var{format}, @var{n}) |
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Grammarcheck files for 3.4.1 release.
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22 ## @deftypefnx {Function File} {@var{C} =} textscan (@var{fid}, @var{format}, @var{param}, @var{value}, @dots{}) |
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Grammarcheck files for 3.4.1 release.
Rik <octave@nomad.inbox5.com>
parents:
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23 ## @deftypefnx {Function File} {@var{C} =} textscan (@var{fid}, @var{format}, @var{n}, @var{param}, @var{value}, @dots{}) |
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994e2a93a8e2
Use uppercase 'A' to refer to matrix inputs in m-files.
Rik <octave@nomad.inbox5.com>
parents:
11469
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changeset
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24 ## @deftypefnx {Function File} {@var{C} =} textscan (@var{str}, @dots{}) |
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994e2a93a8e2
Use uppercase 'A' to refer to matrix inputs in m-files.
Rik <octave@nomad.inbox5.com>
parents:
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25 ## @deftypefnx {Function File} {[@var{C}, @var{position}] =} textscan (@dots{}) |
| 11141 | 26 ## Read data from a text file. |
| 27 ## | |
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28 ## The file associated with @var{fid} is read and parsed according to |
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3c6e8aaa9555
Grammarcheck m-files before 3.4 release.
Rik <octave@nomad.inbox5.com>
parents:
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29 ## @var{format}. The function behaves like @code{strread} except it works by |
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3c6e8aaa9555
Grammarcheck m-files before 3.4 release.
Rik <octave@nomad.inbox5.com>
parents:
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30 ## parsing a file instead of a string. See the documentation of |
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3c6e8aaa9555
Grammarcheck m-files before 3.4 release.
Rik <octave@nomad.inbox5.com>
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31 ## @code{strread} for details. In addition to the options supported by |
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3c6e8aaa9555
Grammarcheck m-files before 3.4 release.
Rik <octave@nomad.inbox5.com>
parents:
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32 ## @code{strread}, this function supports one more: |
| 11141 | 33 ## @itemize |
| 34 ## @item "headerlines": | |
| 35 ## @end itemize | |
| 36 ## The first @var{value} number of lines of @var{str} are skipped. | |
| 37 ## | |
| 38 ## The optional input, @var{n}, specifes the number of lines to be read from | |
| 39 ## the file, associated with @var{fid}. | |
| 40 ## | |
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Rik <octave@nomad.inbox5.com>
parents:
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changeset
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41 ## The output, @var{C}, is a cell array whose length is given by the number |
| 11141 | 42 ## of format specifiers. |
| 43 ## | |
| 44 ## The second output, @var{position}, provides the position, in characters, | |
| 45 ## from the beginning of the file. | |
| 46 ## | |
| 47 ## @seealso{dlmread, fscanf, load, strread, textread} | |
| 48 ## @end deftypefn | |
| 49 | |
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Use uppercase 'A' to refer to matrix inputs in m-files.
Rik <octave@nomad.inbox5.com>
parents:
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changeset
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50 function [C, p] = textscan (fid, format, varargin) |
| 11141 | 51 |
| 52 ## Check input | |
| 53 if (nargin < 1) | |
| 54 print_usage (); | |
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Overhaul m-script files to use common variable name between code and documentation.
Rik <octave@nomad.inbox5.com>
parents:
11191
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55 elseif (nargin == 1 || isempty (format)) |
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c776f063fefe
Overhaul m-script files to use common variable name between code and documentation.
Rik <octave@nomad.inbox5.com>
parents:
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56 format = "%f"; |
| 11141 | 57 endif |
| 58 | |
| 59 if (nargin > 2 && isnumeric (varargin{1})) | |
| 60 nlines = varargin{1}; | |
| 61 args = varargin(2:end); | |
| 62 else | |
| 63 nlines = Inf; | |
| 64 args = varargin; | |
| 65 endif | |
| 66 | |
| 67 if (! any (strcmpi (args, "emptyvalue"))) | |
| 68 ## Matlab returns NaNs for missing values | |
| 69 args{end+1} = "emptyvalue"; | |
| 70 args{end+1} = NaN; | |
| 71 endif | |
| 72 | |
| 73 if (isa (fid, "double") && fid > 0 || ischar (fid)) | |
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Overhaul m-script files to use common variable name between code and documentation.
Rik <octave@nomad.inbox5.com>
parents:
11191
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74 if (ischar (format)) |
| 11141 | 75 if (ischar (fid)) |
| 76 if (nargout == 2) | |
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missing semicolons in script files
John W. Eaton <jwe@octave.org>
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77 error ("textscan: cannot provide position information for character input"); |
| 11141 | 78 endif |
| 79 str = fid; | |
| 80 else | |
| 81 ## Maybe skip header lines | |
| 82 headerlines = find (strcmpi (args, "headerlines"), 1); | |
| 83 if (! isempty (headerlines)) | |
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12679
f38cf6224452
Fix textscan/textread headerlines arg always skipping 2 lines (bug #33028)
Philip Nienhuis <prnienhuis@users.sf.net>
parents:
12575
diff
changeset
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84 hdr_lines = floor (varargin{headerlines + 1}); |
|
f38cf6224452
Fix textscan/textread headerlines arg always skipping 2 lines (bug #33028)
Philip Nienhuis <prnienhuis@users.sf.net>
parents:
12575
diff
changeset
|
85 ## Beware of zero valued headerline, fskipl will count lines to EOF |
|
f38cf6224452
Fix textscan/textread headerlines arg always skipping 2 lines (bug #33028)
Philip Nienhuis <prnienhuis@users.sf.net>
parents:
12575
diff
changeset
|
86 if (hdr_lines > 0) |
|
f38cf6224452
Fix textscan/textread headerlines arg always skipping 2 lines (bug #33028)
Philip Nienhuis <prnienhuis@users.sf.net>
parents:
12575
diff
changeset
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87 fskipl (fid, hdr_lines); |
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f38cf6224452
Fix textscan/textread headerlines arg always skipping 2 lines (bug #33028)
Philip Nienhuis <prnienhuis@users.sf.net>
parents:
12575
diff
changeset
|
88 endif |
| 11141 | 89 endif |
| 90 if (isfinite (nlines)) | |
| 91 str = ""; | |
| 92 for n = 1:nlines | |
| 93 str = strcat (str, fgets (fid)); | |
| 94 endfor | |
| 95 else | |
| 96 str = fread (fid, "char=>char").'; | |
| 97 endif | |
| 98 endif | |
| 99 | |
| 100 ## Determine the number of data fields | |
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11469
c776f063fefe
Overhaul m-script files to use common variable name between code and documentation.
Rik <octave@nomad.inbox5.com>
parents:
11191
diff
changeset
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101 num_fields = numel (strfind (format, "%")) - ... |
|
c776f063fefe
Overhaul m-script files to use common variable name between code and documentation.
Rik <octave@nomad.inbox5.com>
parents:
11191
diff
changeset
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102 numel (idx_star = strfind (format, "%*")); |
| 11141 | 103 |
| 104 ## Call strread to make it do the real work | |
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11471
994e2a93a8e2
Use uppercase 'A' to refer to matrix inputs in m-files.
Rik <octave@nomad.inbox5.com>
parents:
11469
diff
changeset
|
105 C = cell (1, num_fields); |
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994e2a93a8e2
Use uppercase 'A' to refer to matrix inputs in m-files.
Rik <octave@nomad.inbox5.com>
parents:
11469
diff
changeset
|
106 [C{:}] = strread (str, format, args{:}); |
| 11141 | 107 |
| 108 if (ischar (fid) && isfinite (nlines)) | |
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11471
994e2a93a8e2
Use uppercase 'A' to refer to matrix inputs in m-files.
Rik <octave@nomad.inbox5.com>
parents:
11469
diff
changeset
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109 C = cellfun (@(x) x(1:nlines), C, "uniformoutput", false); |
| 11141 | 110 endif |
| 111 | |
| 112 if (nargout == 2) | |
| 113 p = ftell (fid); | |
| 114 endif | |
| 115 | |
| 116 else | |
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Use uppercase for variable names in error() strings to match Info documentation. Only m-files done.
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117 error ("textscan: FORMAT must be a valid specification"); |
| 11141 | 118 endif |
| 119 else | |
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Use uppercase for variable names in error() strings to match Info documentation. Only m-files done.
Rik <octave@nomad.inbox5.com>
parents:
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diff
changeset
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120 error ("textscan: first argument must be a file id or character string"); |
| 11141 | 121 endif |
| 122 | |
| 123 endfunction | |
| 124 | |
| 125 %!test | |
| 126 %! str = "1, 2, 3, 4\n 5, , , 8\n 9, 10, 11, 12"; | |
| 127 %! fmtstr = "%f %d %f %s"; | |
| 128 %! c = textscan (str, fmtstr, 2, "delimiter", ",", "emptyvalue", -Inf); | |
| 129 %! assert (isequal (c{1}, [1;5])) | |
| 130 %! assert (length (c{1}), 2); | |
| 131 %! assert (iscellstr (c{4})) | |
| 132 %! assert (isequal (c{3}, [3; -Inf])) | |
| 133 | |
| 134 %!test | |
| 135 %! b = [10:10:100]; | |
| 136 %! b = [b; 8*b/5]; | |
| 137 %! str = sprintf ("%g miles/hr = %g kilometers/hr\n", b); | |
| 138 %! fmt = "%f miles/hr = %f kilometers/hr"; | |
| 139 %! c = textscan (str, fmt); | |
| 140 %! assert (b(1,:)', c{1}) | |
| 141 %! assert (b(2,:)', c{2}) | |
| 142 | |
| 143 |