CTEXTREAD Read formatted data from text file. Modified from Matlab
TEXTREAD to avoid use of WHICH()
A = TEXTREAD('FILENAME')
A = TEXTREAD('FILENAME','',N)
A = TEXTREAD('FILENAME','',param,value, ...)
A = TEXTREAD('FILENAME','',N,param,value, ...) reads numeric data from
the file FILENAME into a single variable. If the file contains any
text data, an error is produced. FILENAME should include a
correct path, either relative to the current directory or
fully qualified.
[A,B,C, ...] = TEXTREAD('FILENAME','FORMAT')
[A,B,C, ...] = TEXTREAD('FILENAME','FORMAT',N)
[A,B,C, ...] = TEXTREAD('FILENAME','FORMAT',param,value, ...)
[A,B,C, ...] = TEXTREAD('FILENAME','FORMAT',N,param,value, ...) reads
data from the file FILENAME into the variables A,B,C,etc. The type of
each return argument is given by the FORMAT string. The number of
return arguments must match the number of conversion specifiers in the
FORMAT string. If there are fewer fields in the file than in the
format string, an error is produced. See FORMAT STRINGS below for
more information.
If N is specified, the format string is reused N times. If N is -1 (or
not specified) TEXTREAD reads the entire file.
If param,value pairs are supplied, user configurable options customize
the behavior of TEXTREAD. See USER CONFIGURABLE OPTIONS below.
TEXTREAD works by matching and converting groups of characters from the
file. An input field is defined as a string of non-whitespace
characters extending to the next whitespace or delimiter character
or until the field width is exhausted. Repeated delimiter characters
are significant while repeated whitespace characters are treated as
one.
FORMAT STRINGS
If the FORMAT string is empty, TEXTREAD will only numeric data.
The FORMAT string can contain whitespace characters (which are
ignored), ordinary characters (which are expected to match the next
non-whitespace character in the input), or conversion specifications.
If whitespace is set to '' and format types are %s,%q,%[...] and %[^...].
Else whitespace characters are ignored.
Supported conversion specifications:
%n - read a number - float or integer (returns double array)
%5n reads up to 5 digits or until next delimiter
%d - read a signed integer value (returns double array)
%5d reads up to 5 digits or until next delimiter
%u - read an integer value (returns double array)
%5u reads up to 5 digits or until next delimiter
%f - read a floating point value (returns double array)
%5f reads up to 5 digits or until next delimiter
%s - read a whitespace separated string (returns cellstr)
%5s reads up to 5 characters or until whitespace
%q - read a (possibly double quoted) string (returns cellstr)
%5q reads up to 5 non-quote characters or until whitespace
%c - read character or whitespace (returns char array)
%5c reads up to 5 characters including whitespace
%[...] - reads characters matching characters between the
brackets until first non-matching character or
whitespace (returns cellstr)
use %[]...] to include ]
%5[...] reads up to 5 characters
%[^...] - reads characters not matching characters between the
brackets until first matching character or whitespace
(returns cellstr)
use %[^]...] to exclude ]
%5[^...] reads up to 5 characters
Note: Format strings are interpreted as with sprintf before parsing.
For example, textread('mydata.dat','%s\t') will search for a tab not
the character '\' followed by the character 't'. See the Language
Reference Guide or a C manual for complete details.
Using %* instead of % in a conversion causes TEXTREAD to skip the
matching characters in the input (and no output is created for this
conversion). The % can be followed by an optional field width to
handle fixed width fields. For example %5d reads a 5 digit integer. In
addition the %f format supports the form %<width>.<prec>f.
USER CONFIGURABLE OPTIONS
Possible param/value options are:
'bufsize' - maximum string length in bytes (default is 4095)
'commentstyle' - one of
'matlab' -- characters after % are ignored
'shell' -- characters after # are ignored
'c' -- characters between /* and */ are ignored
'c++' -- characters after // are ignored
'delimiter' - delimiter characters (default is none)
'emptyvalue' - empty cell value in delimited files (default is 0)
'endofline' - end of line character (default determined from file)
'expchars' - exponent characters (default is 'eEdD')
'headerlines' - number of lines at beginning of file to skip
'whitespace' - whitespace characters (default is ' \b\t')
TEXTREAD is useful for reading text files with a known format. Both
fixed and free format files can be handled.
Examples:
Suppose the text file mydata.dat contains data in the following form:
Sally Type1 12.34 45 Yes
Joe Type2 23.54 60 No
Bill Type1 34.90 12 No
Read each column into a variable
[names,types,x,y,answer] = textread('mydata.dat','%s%s%f%d%s');
Read first column into a cell array (skipping rest of line)
[names]=textread('mydata.dat','%s%*[^\n]')
Read first character into char array (skipping rest of line)
[initials]=textread('mydata.dat','%c%*[^\n]')
Read file as a fixed format file while skipping the doubles
[names,types,y,answer] = textread('mydata.dat','%9c%5s%*f%2d%3s');
Read file and match Type literal
[names,typenum,x,y,answer]=textread('mydata.dat','%sType%d%f%d%s');
Read m-file into cell array of strings
file = textread('fft.m','%s','delimiter','\n','whitespace','');
To read all numeric data from a delimited text file, use a single output
argument, empty format string, and the appropriate delimiter. For
example, suppose data.csv contains:
1,2,3,4
5,6,7,8
9,10,11,12
Read the whole matrix into a single variable:
[data] = textread('data.csv','','delimiter',',');
Read the first two columns into two variables:
[col1, col2] = textread('data.csv','%n%n%*[^\n]','delimiter',',');
For files with empty cells, use the emptyvalue parameter. Suppose
data.csv contains:
1,2,3,4,,6
7,8,9,,11,12
Read the file like this, using NaN in empty cells:
[data] = textread('data.csv','','delimiter',',','emptyvalue',NaN);
See also TEXTREAD, DLMREAD, LOAD, STRREAD, SSCANF, XLSREAD.0001 function varargout = ctextread(varargin); 0002 %CTEXTREAD Read formatted data from text file. Modified from Matlab 0003 % TEXTREAD to avoid use of WHICH() 0004 % A = TEXTREAD('FILENAME') 0005 % A = TEXTREAD('FILENAME','',N) 0006 % A = TEXTREAD('FILENAME','',param,value, ...) 0007 % A = TEXTREAD('FILENAME','',N,param,value, ...) reads numeric data from 0008 % the file FILENAME into a single variable. If the file contains any 0009 % text data, an error is produced. FILENAME should include a 0010 % correct path, either relative to the current directory or 0011 % fully qualified. 0012 % 0013 % [A,B,C, ...] = TEXTREAD('FILENAME','FORMAT') 0014 % [A,B,C, ...] = TEXTREAD('FILENAME','FORMAT',N) 0015 % [A,B,C, ...] = TEXTREAD('FILENAME','FORMAT',param,value, ...) 0016 % [A,B,C, ...] = TEXTREAD('FILENAME','FORMAT',N,param,value, ...) reads 0017 % data from the file FILENAME into the variables A,B,C,etc. The type of 0018 % each return argument is given by the FORMAT string. The number of 0019 % return arguments must match the number of conversion specifiers in the 0020 % FORMAT string. If there are fewer fields in the file than in the 0021 % format string, an error is produced. See FORMAT STRINGS below for 0022 % more information. 0023 % 0024 % If N is specified, the format string is reused N times. If N is -1 (or 0025 % not specified) TEXTREAD reads the entire file. 0026 % 0027 % If param,value pairs are supplied, user configurable options customize 0028 % the behavior of TEXTREAD. See USER CONFIGURABLE OPTIONS below. 0029 % 0030 % TEXTREAD works by matching and converting groups of characters from the 0031 % file. An input field is defined as a string of non-whitespace 0032 % characters extending to the next whitespace or delimiter character 0033 % or until the field width is exhausted. Repeated delimiter characters 0034 % are significant while repeated whitespace characters are treated as 0035 % one. 0036 % 0037 % FORMAT STRINGS 0038 % 0039 % If the FORMAT string is empty, TEXTREAD will only numeric data. 0040 % 0041 % The FORMAT string can contain whitespace characters (which are 0042 % ignored), ordinary characters (which are expected to match the next 0043 % non-whitespace character in the input), or conversion specifications. 0044 % 0045 % If whitespace is set to '' and format types are %s,%q,%[...] and %[^...]. 0046 % Else whitespace characters are ignored. 0047 % 0048 % Supported conversion specifications: 0049 % %n - read a number - float or integer (returns double array) 0050 % %5n reads up to 5 digits or until next delimiter 0051 % %d - read a signed integer value (returns double array) 0052 % %5d reads up to 5 digits or until next delimiter 0053 % %u - read an integer value (returns double array) 0054 % %5u reads up to 5 digits or until next delimiter 0055 % %f - read a floating point value (returns double array) 0056 % %5f reads up to 5 digits or until next delimiter 0057 % %s - read a whitespace separated string (returns cellstr) 0058 % %5s reads up to 5 characters or until whitespace 0059 % %q - read a (possibly double quoted) string (returns cellstr) 0060 % %5q reads up to 5 non-quote characters or until whitespace 0061 % %c - read character or whitespace (returns char array) 0062 % %5c reads up to 5 characters including whitespace 0063 % %[...] - reads characters matching characters between the 0064 % brackets until first non-matching character or 0065 % whitespace (returns cellstr) 0066 % use %[]...] to include ] 0067 % %5[...] reads up to 5 characters 0068 % %[^...] - reads characters not matching characters between the 0069 % brackets until first matching character or whitespace 0070 % (returns cellstr) 0071 % use %[^]...] to exclude ] 0072 % %5[^...] reads up to 5 characters 0073 % 0074 % Note: Format strings are interpreted as with sprintf before parsing. 0075 % For example, textread('mydata.dat','%s\t') will search for a tab not 0076 % the character '\' followed by the character 't'. See the Language 0077 % Reference Guide or a C manual for complete details. 0078 % 0079 % Using %* instead of % in a conversion causes TEXTREAD to skip the 0080 % matching characters in the input (and no output is created for this 0081 % conversion). The % can be followed by an optional field width to 0082 % handle fixed width fields. For example %5d reads a 5 digit integer. In 0083 % addition the %f format supports the form %<width>.<prec>f. 0084 % 0085 % USER CONFIGURABLE OPTIONS 0086 % 0087 % Possible param/value options are: 0088 % 'bufsize' - maximum string length in bytes (default is 4095) 0089 % 'commentstyle' - one of 0090 % 'matlab' -- characters after % are ignored 0091 % 'shell' -- characters after # are ignored 0092 % 'c' -- characters between /* and */ are ignored 0093 % 'c++' -- characters after // are ignored 0094 % 'delimiter' - delimiter characters (default is none) 0095 % 'emptyvalue' - empty cell value in delimited files (default is 0) 0096 % 'endofline' - end of line character (default determined from file) 0097 % 'expchars' - exponent characters (default is 'eEdD') 0098 % 'headerlines' - number of lines at beginning of file to skip 0099 % 'whitespace' - whitespace characters (default is ' \b\t') 0100 % 0101 % TEXTREAD is useful for reading text files with a known format. Both 0102 % fixed and free format files can be handled. 0103 % 0104 % Examples: 0105 % Suppose the text file mydata.dat contains data in the following form: 0106 % Sally Type1 12.34 45 Yes 0107 % Joe Type2 23.54 60 No 0108 % Bill Type1 34.90 12 No 0109 % 0110 % Read each column into a variable 0111 % [names,types,x,y,answer] = textread('mydata.dat','%s%s%f%d%s'); 0112 % 0113 % Read first column into a cell array (skipping rest of line) 0114 % [names]=textread('mydata.dat','%s%*[^\n]') 0115 % 0116 % Read first character into char array (skipping rest of line) 0117 % [initials]=textread('mydata.dat','%c%*[^\n]') 0118 % 0119 % Read file as a fixed format file while skipping the doubles 0120 % [names,types,y,answer] = textread('mydata.dat','%9c%5s%*f%2d%3s'); 0121 % 0122 % Read file and match Type literal 0123 % [names,typenum,x,y,answer]=textread('mydata.dat','%sType%d%f%d%s'); 0124 % 0125 % Read m-file into cell array of strings 0126 % file = textread('fft.m','%s','delimiter','\n','whitespace',''); 0127 % 0128 % To read all numeric data from a delimited text file, use a single output 0129 % argument, empty format string, and the appropriate delimiter. For 0130 % example, suppose data.csv contains: 0131 % 1,2,3,4 0132 % 5,6,7,8 0133 % 9,10,11,12 0134 % 0135 % Read the whole matrix into a single variable: 0136 % [data] = textread('data.csv','','delimiter',','); 0137 % 0138 % Read the first two columns into two variables: 0139 % [col1, col2] = textread('data.csv','%n%n%*[^\n]','delimiter',','); 0140 % 0141 % For files with empty cells, use the emptyvalue parameter. Suppose 0142 % data.csv contains: 0143 % 1,2,3,4,,6 0144 % 7,8,9,,11,12 0145 % 0146 % Read the file like this, using NaN in empty cells: 0147 % [data] = textread('data.csv','','delimiter',',','emptyvalue',NaN); 0148 % 0149 % 0150 % See also TEXTREAD, DLMREAD, LOAD, STRREAD, SSCANF, XLSREAD. 0151 0152 % Clay M. Thompson 3-3-98 0153 % Copyright 1984-2002 The MathWorks, Inc. 0154 % Based on MathWorks Revision: 1.16 $ $Date: 2002/06/05 20:10:18 0155 0156 % $Id: ctextread.m,v 1.1 2004/05/19 15:03:59 stuver Exp $ 0157 0158 % do some preliminary error checking 0159 error(nargchk(1,inf,nargin)); 0160 0161 % From MathWorks textread: commented out 0162 %if (exist(varargin{1}) ~= 2 | exist(fullfile(cd,varargin{1})) ~= 2) & ~isempty(which(varargin{1})) 0163 % varargin{1} = which(varargin{1}); 0164 %end 0165 0166 if exist(varargin{1}) ~= 2 0167 error('File not found.'); 0168 end 0169 0170 if nargout == 0 0171 nlhs = 1; 0172 else 0173 nlhs = nargout; 0174 end 0175 0176 [varargout{1:nlhs}]=dataread('file',varargin{:}); 0177 0178 return