% script to bracket a solutioon to the projectileKin.m problem
% HW1, PHYS220 Spring 2009

% givens (from problem statement)
target = 100;
vo = 50;

% some constants & starting values
tol = 1;        % we'll allow a miss of up to this amount
theta = 45;     % start at a neutral angle (max range)
stepTheta = 20; % coarse starting search
stepDiv = 2;    % cut step in half on each bracket

% initial range
[yMax,range,tof] = projectileKin(vo,theta);

% for display purposes
disp(' ')
disp('theta (deg) range (m)  Dtheta (deg)')
disp([theta range stepTheta])

% search over angles, cut steps in half every time we pass target, display
% each step in the bracketing operation
while abs(target-range) > tol
    theta = theta + stepTheta;
    [yMax,range,tof] = projectileKin(vo,theta);
    disp([theta range stepTheta])
    if sign(target-range) == sign(stepTheta)
        stepTheta = -stepTheta/stepDiv;
    end
end

return