title: Legend for multiple lines in Matlab plot
body: <p>I have 13 lines on a plot, each line corresponding to a set of data from a text file.  I'd like to label each line starting with the first set of data as 1.2, then subsequently 1.25, 1.30, to 1.80, etc., with each increment be 0.05.  If I were to type it out manually, it would be </p>
  
  <pre><code>legend('1.20','1.25','1.30', ...., '1.80')
  </code></pre>
  
  <p>However, in the future, I might have more than 20 lines on the graph.  So typing out each one is unrealistic. I tried creating a loop in the legend and it doesn't work. </p>
  
  <p>How can I do this in a practical way?</p>
  
  <hr>
  
  <pre><code>N_FILES=13 ; 
  N_FRAMES=2999 ; 
  a=1.20 ;b=0.05 ; 
  phi_matrix = zeros(N_FILES,N_FRAMES) ; 
  for i=1:N_FILES
      eta=a + (i-1)*b ; 
      fname=sprintf('phi_per_timestep_eta=%3.2f.txt', eta) ; 
      phi_matrix(i,:)=load(fname);
  end 
  figure(1);
  x=linspace(1,N_FRAMES,N_FRAMES) ;
  plot(x,phi_matrix) ; 
  </code></pre>
  
  <p>Need help here: </p>
  
  <pre><code>legend(a+0*b,a+1*b,a+2*b, ...., a+N_FILES*b)
  </code></pre>