Boundary Value Problems $($BVPs$)$ may be solved using standard initial$-$value$-$problem integrators $($like ode$45)$ by guessing the some of the initial values and checking to see if those produce the required final values $($as with the in$-$class temperature problem$).$ Here, use an automated technique $($specifically$,$ root finding$)$ to determine the temperature distribution in a circular rod with internal heat source S$,$ governed by the differential equation: d$^2$T$/$dr$^2-1/$r dT$/$dr $+$S$=0$ with the boundary conditions T$(1)=1,$ dT$/$dr$(0)=0$ for S$=1,10,20$ in matlab