function yE=yE(t,y)

R=20000;					%Resistance
C=.00001;					%Capacitance
E0=117;						%Constant Voltage
gam=1/(R*C);
yE=E0*C*(ones(size(t))-exp(-gam*t));		%Exact solution
						%the ones() command creates
						%a vector of ones
