% falling ball demo script -- fall.m
% Author: F. P. Schloerb
% computes solution of falling object under force of gravity
%    x(t) = x(0) - 1/2 g t^2
%

% define an array of times for calculation
% array t spans times from 0 to 10 seconds in steps of 1s
t = 0:1:10;

% get the initial height from the user:
h = input('Enter initial height (m): ');

% compute the array of positions corresponding to array of times, t
% note use of .* operator for element-by-element multiplication of t arrays
x = h - 0.5 * 9.8 * t.*t;

% plot the result - with labels for axes
plot(t,x);
xlabel('time (s)');
ylabel('position (m)');
title('Falling Ball');

% display results in a table that looks nice
fprintf('Here are results:\n')
fprintf('   t         x\n')
fprintf('  ---    -------\n')
for i=1:11
	fprintf('%5.1f %10.2f\n',t(i),x(i))
end