% 
% Example of using relational and logical operators to create arrays
% that represent signals with discontinuities, or with other signals
% replacing a segment of the original signal.
% 
% Main idea: Multiply the values in an array you want to keep by ones,
% and multiply all the other values by zeros. Then you can replace
% the zero-ed out entries with other values by adding into them
% signals which themselves have zeros on the segments you want to keep.
% 
% Confusing explanation? Good. Then insert intermediate plots for the
% intermediate values of the arrays y and z to see how the desired
% signal vector is created.
% 
%
% For A321 course
%
%     Last Modified: Mon 04 Feb 2008, 11:16 AM
%


x = linspace(1,10,1000);

y = sin(x);


z = (y >= 0).*y;   % Gives array same as y, but with negatives values
                   % set to zero

z = z + 0.5*(y < 0);   % Where sin(x) is negative, add 1/2

z = (x <= 8) .* z;     % Set values past x = 8 to be zero

plot(x, z );

xlabel('x');

ylabel('z = f(x)');

title('Discontinuous Signal Example (mostly from Hanselman and Littlefield)')