matlab: delimit .csv file where no specific delimiter is available - matlab

Question

i wonder if there is the possibility to read a .csv file looking like:
0,0530,0560,0730,....
90,15090,15290,157....
i should get:
0,053 0,056 0,073 0,...
90,150 90,152 90,157 90,...
when using dlmread(path, '') matlab spits out an error saying
Mismatch between file and Format character vector.
Trouble reading 'Numeric' field frin file (row 1, field number 2) ==> ,053 0,056 0,073 ...
i also tried using "0," as the delimiter but matlab prohibits this.
Thanks,
jonnyx

Answer 1

str= importdata('file.csv',''); %importing the data as a cell array of char
for k=1:length(str) %looping till the last line
str{k}=myfunc(str{k}); %applying the required operation
end
where
function new=myfunc(str)
old = str(1:regexp(str, ',', 'once')); %finding the characters till the first comma
%old is the pattern of the current line
new=strrep(str,old,[' ',old]); %adding a space before that pattern
new=new(2:end); %removing the space at the start
end
and file.csv :
0,0530,0560,073
90,15090,15290,157
Output:
>> str
str=
'0,053 0,056 0,073'
'90,150 90,152 90,157'

Answer 2

You can actually do this using textscan without any loops and using a few basic string manipulation functions:
fid = fopen('no_delim.csv', 'r');
C = textscan(fid, ['%[0123456789' 10 13 ']%[,]%3c'], 'EndOfLine', '');
fclose(fid);
C = strcat(C{:});
output = strtrim(strsplit(sprintf('%s ', C{:}), {'\n' '\r'})).';
And the output using your sample input file:
output =
2×1 cell array
'0,053 0,056 0,073'
'90,150 90,152 90,157'
How it works...
The format string specifies 3 items to read repeatedly from the file:
A string containing any number of characters from 0 through 9, newlines (ASCII code 10), or carriage returns (ASCII code 13).
A comma.
Three individual characters.
Each set of 3 items are concatenated, then all sets are printed to a string separated by spaces. The string is split at any newlines or carriage returns to create a cell array of strings, and any spaces on the ends are removed.

Answer 3

If you have access to a GNU / *NIX command line, I would suggest using sed to preprocess your data before feeding into matlab. The command would be in this case : sed 's/,[0-9]\{3\}/& /g' .
$ echo "90,15090,15290,157" | sed 's/,[0-9]\{3\}/& /g'
90,150 90,152 90,157
$ echo "0,0530,0560,0730,356" | sed 's/,[0-9]\{3\}/& /g'
0,053 0,056 0,073 0,356
also, you easily change commas , to decimal point .
$ echo "0,053 0,056 0,073 0,356" | sed 's/,/./g'
0.053 0.056 0.073 0.356