How can I write strings and matrices to a .txt file in MATLAB?

Question

I need to write data to a .txt file in MATLAB. I know how to write strings (fprintf) or matrices (dlmwrite), but I need something that can do

Answer 1

I think all you have to do to fix your problem is add a carriage return (\r) to your FPRINTF statement and remove the first call to DLMWRITE:

str = 'This is the matrix: ';      %# A string
mat1 = [23 46; 56 67];             %# A 2-by-2 matrix
fName = 'str_and_mat.txt';         %# A file name
fid = fopen(fName,'w');            %# Open the file
if fid ~= -1
  fprintf(fid,'%s\r\n',str);       %# Print the string
  fclose(fid);                     %# Close the file
end
dlmwrite(fName,mat1,'-append',...  %# Print the matrix
         'delimiter','\t',...
         'newline','pc');

And the output in the file looks like this (with tabs between the numbers):

This is the matrix: 
23  46
56  67

NOTE: A short explanation... the reason for needing the \r in the FPRINTF statement is because a PC line terminator is comprised of a carriage return followed by a line feed, which is what is used by DLMWRITE when the 'newline','pc' option is specified. The \r is needed to ensure the first line of the matrix appears on a new line when opening the output text file in Notepad.