% Example 9.2a (Physics 330)

clear;
a=1;b=3;

% If the number a is positive set c to 1; if a is 0 or negative,
% set c to zero

if a>0
   c=1
else
   c=0
end

% if either a or b is non-negative, add them to obtain c;
% otherwise multiply a and b to obtain c

if a>=0 | b>=0  % either non-negative
   c=a+b
else
   c=a*b  % otherwise multiply them to obtain c
end