x=0:0.35:7;
y=2*exp(-0.5*x);
subplot(1,3,1);scatter(x,y,'green');
title('scatter(x,y,''green'')');axis([0,7,0,2]);
subplot(1,3,2);stairs(x,y,'b');
title('stairs(x,y,''b'')');axis([0,7,0,2]);
subplot(1,3,3);stem(x,y,'k');
title('stem(x,y,''k'')');axis([0,7,0,2]);