# HG changeset patch
# User Soren Hauberg <address@hidden>
# Date 1255976380 -7200
# Node ID 733359750f7c0eec057342aa9dd27a329e6e6c2a
# Parent  78ac37d735577196763c36249727557a1e9ce3da
scripts/io/strread.m scripts/io/textread.m: new functions

diff -r 78ac37d73557 -r 733359750f7c scripts/ChangeLog
--- a/scripts/ChangeLog	Mon Oct 19 12:12:58 2009 +0200
+++ b/scripts/ChangeLog	Mon Oct 19 20:19:40 2009 +0200
@@ -1,3 +1,7 @@
+2009-10-19  Soren Hauberg  <address@hidden>
+
+	* io/strread.m io/textread.m: New functions.
+
 2009-10-15  David Bateman  <address@hidden>
 
 	* plot/__go_draw_axes__.m: Allow line and surface markerfacecolor
diff -r 78ac37d73557 -r 733359750f7c scripts/io/Makefile.in
--- a/scripts/io/Makefile.in	Mon Oct 19 12:12:58 2009 +0200
+++ b/scripts/io/Makefile.in	Mon Oct 19 20:19:40 2009 +0200
@@ -32,7 +32,7 @@
 INSTALL_PROGRAM = @INSTALL_PROGRAM@
 INSTALL_DATA = @INSTALL_DATA@
 
-SOURCES = beep.m csvread.m csvwrite.m dlmwrite.m
+SOURCES = beep.m csvread.m csvwrite.m dlmwrite.m strread.m textread.m
 
 DISTFILES = $(addprefix $(srcdir)/, Makefile.in $(SOURCES))
 
diff -r 78ac37d73557 -r 733359750f7c scripts/io/strread.m
--- /dev/null	Thu Jan 01 00:00:00 1970 +0000
+++ b/scripts/io/strread.m	Mon Oct 19 20:19:40 2009 +0200
@@ -0,0 +1,248 @@
+## Copyright (C) 2009 Eric Chassande-Mottin, CNRS (France)
+##
+## This program 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.
+##
+## This program 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 this program; if not, see
+## <http://www.gnu.org/licenses/>.
+
+## -*- texinfo -*-
+## @deftypefn {Function File}  address@hidden, @dots{}] =} strread (@var{str})
+## @deftypefnx {Function File}  address@hidden, @dots{}] =} strread (@var{str}, @var{format})
+## @deftypefnx {Function File} address@hidden, @dots{}] =} strread (@var{str}, @var{format}, @
+## @var{prop1}, @var{value1}, @dots{})
+## Read data from a string.
+##
+## The string @var{str} is split into words that are repeatedly matched to the
+## specifiers in @var{format}. The first word is matched to the first specifier,
+## the second to the second specifier and so forth. If there are more words than
+## specifiers, the process is repeated until all words have been processed.
+##
+## The string @var{format} describes how the words in @var{str} should be parsed.
+## It may contain any combination of the following specifiers:
+## @table @code
+## @item %s
+## The word is parsed as a string.
+## @item %d
+## @itemx %f
+## The word is parsed as a number.
+## @item %*
+## The word is skipped.
+## @end table
+##
+## Parsed word corresponding to the first specifier are returned in the first
+## output argument and likewise for the rest of the specifiers.
+##
+## By default, @var{format} is @t{"%f"}, meaning that numbers are read from @var{str}.
+##
+## For example, the string
+##
+## @example
+## @group
+## @var{str} = "\
+## Bunny Bugs   5.5\n\
+## Duck Daffy  -7.5e-5\n\
+## Penguin Tux   6"
+## @end group
+## @end example
+##
+## can be read using
+##
+## @example
+## address@hidden, @var{b}, @var{c}] = strread (@var{str}, "%s %s %f");
+## @end example
+##
+## The behaviour of @code{strread} can be changed via properties @var{prop}
+## @itemize @code
+## @item "headerlines":
+## The first @var{value} number of lines of @var{str} are skipped.
+## @item "commentstyle":
+## Parts of @var{str} are considered comments and will be skipped.
+## @var{value} is the comment style and can be any of the following.
+## @itemize
+## @item "shell"
+## Everything from @code{#} characters to the nearest end-line is skipped.
+## @item "c"
+## Everything between @code{/*} and @code{*/} is skipped.
+## @item "c++"
+## Everything from @code{//} characters to the nearest end-line is skipped.
+## @item "matlab"
+## Everything from @code{%} characters to the nearest end-line is skipped.
+## @end itemize
+## @item "delimiter"
+## Any character in @var{value} will be used to split @var{str} into words.
+## @item "emptyvalue"
+## Parts of the output where no word is available is filled with @var{value}.
+## @end itemize
+##
+## @seealso{textread, load, dlmread, fscanf}
+## @end deftypefn
+
+function varargout = strread (str, formatstr = "%f", varargin)
+  ## Check input
+  if (nargin < 1)
+    print_usage ();
+  endif
+  
+  if (!ischar (str) || !ischar (str))
+    error ("strread: first and second input arguments must be strings");
+  endif
+
+  ## Parse options
+  comment_flag = false;
+  header_skip = 0;
+  numeric_fill_value = 0;
+  white_spaces = " \n\r\t\b";
+  for n = 1:2:length (varargin)
+    switch (lower (varargin {n}))
+      case "commentstyle"
+        comment_flag = true;
+        switch (lower (varargin {n+1}))
+          case "c"
+            comment_specif = {"/*", "*/"};
+          case "c++"
+            comment_specif = {"//", "\n"};
+          case "shell"
+            comment_specif = {"#", "\n"};
+          case "matlab"
+            comment_specif = {"%", "\n"};
+          otherwise
+            warning ("strread: unknown comment style '%s'", val);
+        endswitch
+      case "headerlines"
+        header_skip = varargin {n+1};
+      case "delimiter"
+	delimiter_str = varargin {n+1};
+      case "emptyvalue"
+	numeric_fill_value = varargin {n+1};
+      case "bufsize"
+        ## XXX: We could synthesize this, but that just seems weird...
+	warning ("strread: property \"bufsize\"  is not implemented");
+      case "whitespace"
+	white_spaces = varargin {n+1}; 
+      case "expchars"
+	warning ("strread: property \"expchars\"  is not implemented");
+      otherwise
+        warning ("strread: unknown property \"%s\"", varargin {n});
+    endswitch
+  endfor
+
+  ## Parse format string
+  idx = strfind (formatstr, "%")';
+  specif = formatstr ([idx, idx+1]);
+  nspecif = length (idx);
+  idx_star = strfind (formatstr, "%*");
+  nfields = length (idx) - length (idx_star);
+
+  if (max (nargout, 1) != nfields)
+    error ("strread: the number of output variables must match that of format specifiers");
+  endif
+
+  ## Remove header
+  if (header_skip > 0)
+    e = find (str == "\n", header_skip);
+    if (length (e) >= header_skip)
+      str = str (e (end)+1:end);
+    else
+      ## We don't have enough data so we discard it all
+      str = "";
+    endif
+  endif
+
+  ## Remove comments
+  if (comment_flag)
+    cstart = strfind (str, comment_specif{1});
+    cstop  = strfind (str, comment_specif{2});
+    if (length (cstart) > 0)
+      ## Ignore nested openers.
+      [idx, cidx] = unique (lookup (cstop, cstart), "first");
+      if (idx(end) == length (cstop))
+        cidx(end) = []; # Drop the last one if orphaned.
+      endif
+      cstart = cstart(cidx);
+    endif
+    if (length (cstop) > 0)
+      ## Ignore nested closers.
+      [idx, cidx] = unique (lookup (cstart, cstop), "first");
+      if (idx(1) == 0)
+        cidx(1) = []; # Drop the first one if orphaned.
+      endif
+      cstop = cstop(cidx);
+    endif
+    len = length (str);
+    c2len = length (comment_specif{2});
+    str = cellslices (str, [1, cstop + c2len], [cstart - 1, len]);
+    str = [str{:}];
+  endif
+  
+  ## Split 'str' into words
+  words = split_by (str, white_spaces);
+  num_words = numel (words);
+  num_lines = ceil (num_words / nspecif);
+  
+  ## For each specifier
+  k = 1;
+  for m = 1:nspecif
+    data = words (m:nspecif:end);
+
+    ## Map to format
+    switch specif (m, :)
+      case "%s"
+        data (end+1:num_lines) = {""};
+        varargout {k} = data';
+        k++;
+      case {"%d", "%f"}
+        data = str2double (data);
+        data (end+1:num_lines) = numeric_fill_value;
+        varargout {k} = data.';
+        k++;
+      case "%*"
+        ## do nothing
+    endswitch
+  endfor
+endfunction
+
+function out = split_by (text, sep)
+  out = strtrim (strsplit (text, sep, true));
+endfunction
+
+%!test
+%! str = "# comment\n# comment\n1 2 3";
+%! [a, b] = strread (str, '%d %s', 'commentstyle', 'shell');
+%! assert (a, [1; 3]);
+%! assert (b, {"2"; ""});
+
+%!test
+%! str = '';
+%! a = rand (10, 1);
+%! b = char (round (65 + 20 * rand (10, 1)));
+%! for k = 1:10
+%!   str = sprintf ('%s %.6f %s\n', str, a (k), b (k));
+%! endfor
+%! [aa, bb] = strread (str, '%f %s');
+%! assert (a, aa, 1e-5);
+%! assert (cellstr (b), bb);
+
+%!test
+%! str = '';
+%! a = rand (10, 1);
+%! b = char (round (65 + 20 * rand (10, 1)));
+%! for k = 1:10
+%!   str = sprintf ('%s %.6f %s\n', str, a (k), b (k));
+%! endfor
+%! aa = strread (str, '%f %*s');
+%! assert (a, aa, 1e-5);
+
+%!test
+%! str = sprintf ('/* this is\nacomment*/ 1 2 3');
+%! a = strread (str, '%f', 'commentstyle', 'c');
+%! assert (a, [1; 2; 3]);
+
diff -r 78ac37d73557 -r 733359750f7c scripts/io/textread.m
--- /dev/null	Thu Jan 01 00:00:00 1970 +0000
+++ b/scripts/io/textread.m	Mon Oct 19 20:19:40 2009 +0200
@@ -0,0 +1,51 @@
+## Copyright (C) 2009 Eric Chassande-Mottin, CNRS (France)
+##
+## This program 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.
+##
+## This program 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 this program; if not, see
+## <http://www.gnu.org/licenses/>.
+
+## -*- texinfo -*-
+## @deftypefn {Function File}  address@hidden, @dots{}] =} textread (@var{filename})
+## @deftypefnx {Function File}  address@hidden, @dots{}] =} textread (@var{filename}, @var{format})
+## @deftypefnx {Function File} address@hidden, @dots{}] =} textread (@var{filename}, @var{format}, @
+## @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.
+## @seealso{strread, load, dlmread, fscanf}
+## @end deftypefn
+
+function varargout = textread (filename, formatstr = "%f", varargin)
+  ## Check input
+  if (nargin < 1)
+    print_usage ();
+  endif
+  
+  if (!ischar (filename) || !ischar (filename))
+    error ("textread: first and second input arguments must be strings");
+  endif
+
+  ## Read file
+  fid = fopen (filename, "r");
+  if (fid == -1)
+    error ("textread: could not open '%s' for reading", filename);
+  endif
+  
+  str = char (fread (fid, "char")');
+  fclose (fid);
+  
+  ## Call strread to make it do the real work
+  [varargout{1:max (nargout, 1)}] = strread (str, formatstr, varargin {:});
+endfunction