MATLAB Programming

6 Data Import and Export
• Two spaces
• A fixed-point value of twelve characters with eight decimal places
fprintf converts the elements of array y in column order. The function uses
the format string repeatedly until it converts all the array elements.
Now use fscanf to read the exponential data file:
fid = fopen('exptable.txt','r');
title = fgetl(fid);
[table,count] = fscanf(fid,'%f %f',[2 11]);
table = table';
status = fclose(fid);
Thesecondlinereadsthefiletitle. Thethirdlinereadsthetableofvalues,
two floating-point values on each line, until it reaches end of file. count
returns the number of values matched.
A function related to fprintf, sprintf, outputs its results to a string instead
of a file or the screen. For example,
root2 = sprintf('The square root of %f is %10.8e.\n',2,sqrt(2));
Closing a File
When you finish reading or writing, use fclose to close the file. For example,
this line closes the file associated with file identifier fid:
status = fclose(fid);
This line closes all open files:
status = fclose('all');
Both forms return 0 if the file or files were successfully closed or -1 if the
attempt was unsuccessful.
MATLAB automatically closes all open files when you exit from MATLAB. It
is still good practice, however, to close a file explicitly with fclose when you
are finished using it. Not doing so can unnecessarily drain system resources.
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