###################################
###                             ###
###          MATLAB             ###
###                             ###
###################################

========================================
========  read from keyboard   =========
========================================

a = input('give a number: ');       % for ex. 12 Enter
v = input('give a vector: ');       % for ex. [ 1 2 3] Enter
s = input('give some text (in single quotes): ');   % for ex. 'abc' Enter

b = input('give two numbers: ');
c = input('');                      % for ex. 3 Enter -8.1 Enter

========================================
========   print to screen   ===========
========================================

disp('input data were:');
disp(s), disp(a), disp(v);
disp(['all in one line: ', s, ' ', num2str(a), ', ', num2str(v)]);

a=3;
disp(a);
disp('a');

disp('abcd');


=======================================
=========   advanced print    =========
=======================================

fprintf('abcd');

  % new line
fprintf('ab\ncd\n');

  % printing numbers (in combination with text)
fprintf('whole number %d, decimal number %f \n', 12, 14);

  % format repeats itself, till all the numbers are printed:
fprintf('whole number %d, decimal number %f \n', 12, 14, 123, 7, 5);

fprintf('formatting numbers: %6.2f, %.4f, %.3e  \n', 1, 2, 35);

  % the whole vector can be printed at once
y = 2:0.1:3;
fprintf(' %f, ', y);

  % matrix printing - by columns:
x = 0:0.1:1; 
y = [x; exp(x)];
fprintf('%6.2f  %12.8f\n', y);

  % number of bytes (characters) printed:
nb = fprintf('%d, %d, \n', -6, 40) 


=======================================
=========   print to a file   =========
=======================================

============ easy print ================

save('vysl_y.txt', 'y', '-ascii')  % matrix y is printed to file vysl.txt (as ascii text)  

==== standard print ====================

fid = fopen('vysl.txt','w');      % open file vysl.txt for writing
  % for Windows it should be better to use: fid = fopen('vysl.txt','wt');

fprintf(fid,'results %d\n', 1);  % write to file vysl.txt
y = 2:0.1:3;
fprintf(fid,'%6.2f  %12.8f\n',y); % write to file vysl.txt

fclose(fid);                      % close file vysl.txt


=======================================
=========  reading from a file ========
=======================================

========= easy reading ================

A = load('vysl_y.txt','-ascii');

  % can be used only if there is some matrix in the file, for instance
  %    1  -5  6.1
  %   -2.16  4.71  2
  %    16  20  11
  %   -3.6  6  6 
  % reads matrix from the file and stores it in the variable A
  % (so in the last example, the first line in the file vysl.txt must be erased)
  %
  % if file has .txt suffix, you need not use '-ascii' in the command

==== standard reading ===================

fid = fopen('vysl.txt','r');  % open file vysl.txt for reading

a = fscanf(fid, '%s', 2);  % read the first two words as text (skipping spaces)  
b = fscanf(fid,'%f',4);    % read following 4 numbers - result is a vector

  % n will contain the number of successfully read values (2 here):
[c, n] = fscanf(fid,'%f',2);
  % read until the end of file (or error) occurs:
[d, n] = fscanf(fid,'%f');
  % reshapping of the vector to original shape of 2 columns (use 'help reshape')
y = reshape(d, 2, n/2)';

fclose(fid);                    % close file vysl.txt


==========================================================