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When fprintf, I need a return (\r\n) after each line (with inconstant number of values per line)

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yang
yang on 26 Jun 2013
  • I'm doing a loop to print many lines of data in a file, and I want a return after each line. I am ok with constant number of values per line. But when the number of values per line is not constant, the format of data in the file is not correct.
E.g. use following code to print 3 values (1st line) then 4 values (2nd line) per line
if true
fprintf(File,'%s,%i,%i\r\n',DataArray{:})
end
It shows
a,1,4
b,5,8,
9
What I want is:
a,1,4
b,5,8,9
I know the problem is because I set the number of value to be 3 in the code (%s,%i,%i), so Matlab deem each line has 3 values. But how can I get the format that I need??

  2 Comments

Tom
Tom on 26 Jun 2013
Will the data always have one string, then some number of integers? e.g. '%s %i %i' or '%s %i %i %i' and so on?
yang
yang on 26 Jun 2013
No Tom..the first one is string, the next few are intergers, then with unknown number of strings. i.e.
'%s %i %i %i %s'
or '%s %i %i %i %s %s'
or '%s %i %i %i %s %s %s'
and so on.

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Accepted Answer

Tom
Tom on 26 Jun 2013
Edited: Tom on 26 Jun 2013
Data = {'alpha', 1 , 2 , 3, 'beta' , 'gamma' , 'delta' , 4};
% find locations strings and numeric data:
str = cellfun(@ischar,Data);
num = cellfun(@isnumeric,Data);
t = num2str(str + (num*2)); %number 1 equates to string, 2 equates to numeric
formatStr = [regexprep(t,{'1','2'} , {'%s', '%i'}) ,'\r\n'];
fprintf(File,formatStr)

More Answers (1)

Image Analyst
Image Analyst on 26 Jun 2013
How about
if length(DataArray) == 3
fprintf(File,'%s,%i,%i\r\n',DataArray{:})
else
fprintf(File,'%s,%i,%i %i\r\n',DataArray{:})
end

  2 Comments

yang
yang on 26 Jun 2013
Thanks. But the number of values per line could be any integer, not only 3 or 4....Any other idea?
Image Analyst
Image Analyst on 27 Jun 2013
In the future, it helps to put in those kind of details/requirements in the original question. Otherwise, how would we know?

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