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    %% Write to Text Files Using |fprintf|
% This example shows how to create text files, including combinations of
% numeric and character data and nonrectangular files, using the low-level
% |fprintf| function.
%
% |fprintf| is based on its namesake in the ANSI(R) Standard C Library.
% However, MATLAB(R) uses a vectorized version of |fprintf| that writes data
% from an array with minimal control loops.

%% Open the File
% Create a sample matrix |y| with two rows.
x = 0:0.1:1;
y = [x; exp(x)];
%%
% Open a file for writing with |fopen| and obtain a file identifier, |fileID|. By
% default, |fopen| opens a file for read-only access, so you must specify the
% permission to write or append, such as |'w'| or |'a'|.
fileID = fopen('exptable.txt','w');
%% Write to the File
% Write a title, followed by a blank line using the |fprintf| function. To
% move to a new line in the file, use |'\n'|.
fprintf(fileID, 'Exponential Function\n\n');
%%
% Note: Some Windows(R) text editors, including Microsoft(R) Notepad, require
% a newline character sequence of |'\r\n'| instead of |'\n'|. However, |'\n'| is
% sufficient for Microsoft Word or WordPad.
%%
% Write the values in |y| in column order so that
% two values appear in each row of the file.
% |fprintf| 
% converts the numbers or characters in the array inputs to text
% according to your specifications. Specify |'%f'| to print floating-point
% numbers.
fprintf(fileID,'%f %f\n',y);
%%
% Other common conversion specifiers include |'%d'| for integers or |'%s'| for characters. |fprintf| reapplies the conversion information to cycle through all values
% of the input arrays in column order.
%%
% Close the file using |fclose| when you finish writing. 
fclose(fileID);
%%
% View the contents of the file using the |type| function.
type exptable.txt
%% Additional Formatting Options
% Optionally, include additional information in the call to |fprintf| to
% describe field width, precision, or the order of the output values. For
% example, specify the field width and number of digits to the right of the
% decimal point in the exponential table.
fileID = fopen('exptable_new.txt', 'w');

fprintf(fileID,'Exponential Function\n\n');
fprintf(fileID,'%6.2f %12.8f\n', y);

fclose(fileID);
%%
% View the contents of the file.
type exptable_new.txt