% IAP2007 Introduction to MATLAB: Graphics and Visualization
% Instructor: Violeta Ivanova, violeta@mit.edu

% EXAMPLE 3 Animation

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% A. COMPUTE CURVE THROUGH POINTS

% Compute cubic curve through points with (X,Y) coordinates (2, 75), (3, 86), 
% (5, 82), (6, 70), and (8, 40), along interval x from 0 to 10 with step 0.1.
% Hint: create vectors X and Y, then use functions POLYFIT and POLYVAL.

clear all
X = [2 3 5 6 8]'
Y = [75 86 82 70 40]'
C = polyfit(X, Y, 3)
x = [0 : 0.1 : 10];
y = polyval(C, x);

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% B. CREATE ANIMATION

% B1. Create a figure window
figure
set(gcf, 'Name', 'Cubic Fit Animation')

% B2. Plot the five points.

plot (X, Y, 'ro', 'MarkerFaceColor', 'r')
hold on

% B3. Add an animated plot of the cucic drawn point after point (use different color). 
% Hint: Use functions PLOT, SET, HOLD ON and DRAWNOW inside a FOR loop. 
% Set x-axis limits from 0 to 10, and y-axis limit from 0 to 100.


for i=1:length(x)
    
   p1 = plot(x(i), y(i), 'bo', 'MarkerSize', 4);
   hold on
   % Set the axes to be the same during plotting
   set(gca, 'XLim', [0 10], 'YLim', [0 100]);
   drawnow
   
   % Save the frame in a matrix M to play later
   M(i) = getframe(gcf);
   
end
hold off

% movie2avi(M, 'cubic.avi', 'fps', 30, 'quality', 100);