how to read a text file with delimiter ?

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Amr Hashem
Amr Hashem on 25 Jul 2015
Commented: Amr Hashem on 25 Jul 2015
I have a large text file(.txt) with delimited data , delimiter (|)
which contain numbers, texts, empty cells
i want to open it in matlab , to be something like this
each delimited in a cell
how i can do this?
  1 Comment
Amr Hashem
Amr Hashem on 25 Jul 2015
I try this:
fid = fopen( 'delimite.txt');
data = textscan(fid, '%f%f%s%s%s%s', 'Delimiter', '|','TreatAsEmpty','~');
but it gives me this :
which is not 100% correct

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Accepted Answer

Walter Roberson
Walter Roberson on 25 Jul 2015
%read file
filestr = fileread('YourFile.txt');
%break it into lines
filebyline = regexp(filestr, '\n', 'split');
%remove empty lines
filebyline( cellfun(@isempty,filebyline) ) = [];
%split by fields
filebyfield = regexp(filebyline, '\|', 'split');
%pad out so each line has the same number of fields
numfields = cellfun(@length, filebyfield);
maxfields = max(numfields);
fieldpattern = repmat({[]}, 1, maxfields);
firstN = @(S,N) S(1:N);
filebyfield = cellfun(@(S) firstN([S,fieldpattern], maxfields), filebyfield, 'Uniform', 0);
%switch from cell vector of cell vectors into a 2D cell
fieldarray = vertcat(filebyfield{:});
Now to be consistent with your diagram, we have to convert to numeric not column by column but rather item by item: your row #8 column #3 is converted to a number even though it is the only one in the column that is converted. This is unusual and would typically lead to problems further down the road, but it is what you said you wanted.
%convert all fields to numeric
numarray = str2double(fieldarray);
%switch to cell array of numbers
outarray = num2cell(numarray);
%the places that the strings could not be converted to numbers show up as NaN
conv_failed = isnan(numarray);
%replace the failed conversions with the original text in the cells
outarray(conv_failed) = fieldarray(conv_failed);
The first part of this code, leading up to the creation of "fieldarray", can be made much much compact if the maximum number of fields per line is known in advance.
fields_per_line = 73; %for example
fmt = repmat('%s',1,fields_per_line);
fid = fopen('YourTextFile', 'rt');
filebycolumn = textscan(fid, fmt, 'Delimiter', '|');
fieldarray = horzcat(filebycolumn{:});
  1 Comment
Amr Hashem
Amr Hashem on 25 Jul 2015
it works...
that is what i want :
fields_per_line = 6; %for example
fmt = repmat('%s',1,fields_per_line);
fid = fopen('delimite.txt', 'rt');
filebycolumn = textscan(fid, fmt, 'Delimiter', '|');
fieldarray = horzcat(filebycolumn{:});

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