Displaying/Saving Results

• Type the variable name at the command prompt followed by a return.
  
  
• Use the sprintf command. This command, like it's "C" equivalent gives one more precise format control.

To change the format of the values when they are displayed in the command window use the format command. One can also change this format from the Preferences dialog that appears when the File/Preferences item is selected in the GUI.

To write variables to a file use the fprintf command.

One can also record all activity in a matlab session by using diary command.

Samples

% displaying the internal value of pi

 pi
 ans =
    3.1416

% displaying the value after resetting the format

  format long e
  pi
  ans =
    3.141592653589793e+000

% displaying the value using sprintf

 sprintf('%10.8f \n',pi)
 ans =
 3.14159265 

% generate some x,y data and then save it to the file results.txt

  x = 0.0:.2:1.0;             
  y = sin(x);
  fid = fopen('results.txt','w');    % open the file for writing (overwriting existing data)
  fprintf(fid,'%10.5f ',x);          % print out the x values (fprintf knows about vectors)
  fprintf(fid,'\n');                 % print a linefeed 
  fprintf(fid,'%10.5f ',y);          % print out the y values
  fclose(fid);                       % close the file 

  type results.txt
   0.00000    0.20000    0.40000    0.60000    0.80000    1.00000 
   0.00000    0.19867    0.38942    0.56464    0.71736    0.84147 

% generate some x,y data and then save it to the file results.txt
% in column format

  x = 0.0:.2:1.0;             
  y = sin(x);
  dataOut = [x;y];                           % create a matrix to hold data as columns
  fid = fopen('results.txt','w');            % open file (overwriting existing data)
  fprintf(fid,'%10.5f  %10.5e \n',dataOut);  % write data x in fixed point, y in exponential format
  fclose(fid);                               % close file 

  type results.txt
   0.00000  0.00000e+000 
   0.20000  1.98669e-001 
   0.40000  3.89418e-001 
   0.60000  5.64642e-001 
   0.80000  7.17356e-001 
   1.00000  8.41471e-001 

%
% An example showing how to print out several values in one row
%

  iter= 5;
  x   = 3.0;
  y   = 2.0;
  e   = 5.0;
  v = [iter,x,y,e];                         % put the values in a vector
  sprintf('%4d %10.5e %10.5e %10.5e \n',v)  % use formatted output 

ans =

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