Programming

Writing Binary Data

The fwrite function writes the elements of a matrix to a file in a specified numeric precision, returning the number of values written. For instance, these lines create a 100-byte binary file containing the 25 elements of the 5-by-5 magic square, each stored as 4-byte integers:

• fwriteid = fopen('magic5.bin','w');
  count = fwrite(fwriteid,magic(5),'int32');
  status = fclose(fwriteid);
  

In this case, fwrite sets the count variable to 25 unless an error occurs, in which case the value is less.

Reading Binary Data

Controlling Position in a File

© 1994-2005 The MathWorks, Inc.