Mercurial > hg > octave-lyh
diff scripts/io/textscan.m @ 12914:ac00ae83ea2e
More compatibility improvements for textscan and strread
* strread.m: Implement %u format to int32 type. Fix bug with Mac '\r'
end-of-line character.
* textscan.m: Implement CollectOutput option.
author | Philip Nienhuis <prnienhuis@users.sf.net> |
---|---|
date | Wed, 03 Aug 2011 15:05:28 -0700 |
parents | f5a3f77d51aa |
children | 5d0478a75618 |
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--- a/scripts/io/textscan.m +++ b/scripts/io/textscan.m @@ -34,13 +34,18 @@ ## @code{strread}, this function supports a few more: ## ## @itemize -## @item "headerlines": -## The first @var{value} number of lines of @var{fid} are skipped. +## @item "collectoutput": +## A value of 1 or true instructs textscan to concatenate consecutive columns +## of the same class in the output cell array. A value of 0 or false (default) +## leaves output in distinct columns. ## ## @item "endofline": -## Specify a single character or "\r\n". If no value is given, it will be -## inferred from the file. If set to "" (empty string) EOLs are ignored as -## delimiters. +## Specify "\r", "\n" or "\r\n" (for CR, LF, or CRLF). If no value is given, +## it will be inferred from the file. If set to "" (empty string) EOLs are +## ignored as delimiters and added to whitespace. +## +## @item "headerlines": +## The first @var{value} number of lines of @var{fid} are skipped. ## ## @item "returnonerror": ## If set to numerical 1 or true (default), return normally when read errors @@ -116,6 +121,20 @@ args(end+1:end+2) = {'delimiter', ""}; endif + collop = false; + ipos = find (strcmpi (args, "collectoutput")); + if (! isempty (ipos)) + ## Search & concatenate consecutive columns of same class requested + if (isscalar (args{ipos+1}) + && (islogical (args{ipos+1}) || isnumeric (args{ipos+1}))) + collop = args{ipos+1}; + else + warning ("textscan: illegal value for CollectOutput parameter - ignored"); + endif + ## Remove argument before call to strread() below + args(ipos:ipos+1) = []; + endif + if (any (strcmpi (args, "returnonerror"))) ## Because of the way strread() reads data (columnwise) this parameter ## can't be neatly implemented. strread() will pick it up anyway @@ -164,6 +183,9 @@ if (! isempty (endofline)) if (ischar (args{endofline + 1})) eol_char = args{endofline + 1}; + if (isempty (strmatch (eol_char, {"", "\n", "\r", "\r\n"}, 'exact'))) + error ("textscan: illegal EndOfLine character value specified"); + endif else error ("textscan: character value required for EndOfLine"); endif @@ -195,6 +217,11 @@ ## Call strread to make it do the real work C = cell (1, num_fields); [C{:}] = strread (str, format, args{:}); + + ## If requested, collect output columns of same class + if (collop) + C = colloutp (C); + endif if (nargout == 2) position = ftell (fid); @@ -203,6 +230,32 @@ endfunction +## Collect consecutive columns of same class into one cell column +function C = colloutp (C) + + ## Start at rightmost column and work backwards to avoid ptr mixup + ii = numel (C); + while ii > 1 + clss1 = class (C{ii}); + jj = ii; + while (jj > 1 && strcmp (clss1, class (C{jj - 1}))) + ## Column to the left is still same class; check next column to the left + --jj; + endwhile + if (jj < ii) + ## Concatenate columns into current column + C{jj} = [C{jj : ii}]; + ## Wipe concatenated columns to the right, resume search to the left + C(jj+1 : ii) = []; + ii = jj - 1; + else + ## No similar class in column to the left, search from there + --ii; + endif + endwhile + +endfunction + %!test %! str = "1, 2, 3, 4\n 5, , , 8\n 9, 10, 11, 12"; %! fmtstr = "%f %d %f %s"; @@ -218,13 +271,13 @@ %! str = sprintf ("%g miles/hr = %g kilometers/hr\n", b); %! fmt = "%f miles/hr = %f kilometers/hr"; %! c = textscan (str, fmt); -%! assert (b(1,:)', c{1}); -%! assert (b(2,:)', c{2}); +%! assert (b(1,:)', c{1}, 1e-5); +%! assert (b(2,:)', c{2}, 1e-5); #%!test #%! str = "13, 72, NA, str1, 25\r\n// Middle line\r\n36, na, 05, str3, 6"; #%! a = textscan(str, '%d %n %f %s %n', 'delimiter', ',','treatAsEmpty', {'NA', 'na'},'commentStyle', '//'); -#%! assert (a{1}, [13; 36]); +#%! assert (a{1}, int32([13; 36])); #%! assert (a{2}, [72; NaN]); #%! assert (a{3}, [NaN; 5]); #%! assert (a{4}, {"str1"; "str3"}); @@ -237,9 +290,9 @@ %! str = [str "Km:25 = hhhZ\r\n"]; %! fmt = "Km:%d = hhh%1sjjj miles%dhour"; %! a = textscan (str, fmt, 'delimiter', ' '); -%! assert (a{1}', [10 15 2 25], 1e-5); +%! assert (a{1}', int32([10 15 2 25])); %! assert (a{2}', {'B' 'J' 'R' 'Z'}); -%! assert (a{3}', [16 241 3 NaN], 1e-5); +%! assert (a{3}', int32([16 241 3 0])); %% Test with default endofline parameter %!test @@ -251,6 +304,22 @@ %! c = textscan ("L1\nL2", "%s", 'endofline', ''); %! assert (int8(c{:}{:}), int8([ 76, 49, 10, 76, 50 ])); +%!test +%! # No delimiters at all besides EOL. Skip fields, even empty fields +%! str = "Text1Text2Text\nTextText4Text\nText57Text"; +%! c = textscan (str, "Text%*dText%dText"); +%! assert (c{1}, int32 ([2; 4; 0])); + +%!test +%% CollectOutput test +%! b = [10:10:100]; +%! b = [b; 8*b/5; 8*b*1000/5]; +%! str = sprintf ("%g miles/hr = %g (%g) kilometers (meters)/hr\n", b); +%! fmt = "%f miles%s %s %f (%f) kilometers %*s"; +%! c = textscan (str, fmt, 'collectoutput', 1); +%! assert (size(c{3}), [10, 2]); +%! assert (size(c{2}), [10, 2]); + %% Test input validation %!error textscan () %!error textscan (single (4)) @@ -258,3 +327,4 @@ %!error <must be a string> textscan ("Hello World", 2) %!error <cannot provide position information> [C, pos] = textscan ("Hello World") %!error <character value required> textscan ("Hello World", '%s', 'EndOfLine', 3) +