Advanced File Input and Output:

In that section, we saw how to read the values entered by user using the input as well as the output functions disp and fprintf, that shows information in windows on the screen. For file input and output (file I/O), we used the load and save the functions, that can read from a data file into the matrix, and write from a matrix to a data file. We also saw that there are three various operations which can be performed on files: reading from files, writing to files (implying writing to the starting of a file), and appending to a file (that is writing to the end of the file).

There are many different file types that use dissimilar filename extensions. Faraway, using load and save, we have worked with files in the ASCII format that usually use either the extension .dat or .txt. The load command works only if there are similar number of values in each line and the values are of similar type, so that the data can be stored in a matrix; the save command writes only from the matrix to a file. When the data to be written or file is to be read in a different format, then the lower level file I/O functions should be used.

The MATLAB software has functions which can read and write data from variousfile types like spreadsheets; usually Excel spreadsheets have the filename extension .xls. It has its own binary file type also that uses the extension .mat.

These are generally known as MAT-files, and can be used to store the variables which have been generated in the MATLAB.