obtaining a point solution of a differential equation

i have DE in following form and I am using ode45 to solve for it

[t,y] = ode45(@(t,y) f(t,y), tspan, y(i))

where y(i) is the initial value for current tspan. the problem i am onto has a time dependent f(t,y) i.e., the expression associated with f(t,y) changes at a certain time interval.

for eg: f(t,y)=g(t,y) for [0,t1]

f(t,y)=h(t,y) for [t1,t2] and so on.

so I need to evaluate DE at certain points of time to find out the initial value reqd to solve next DE having different f(x,y) and plot a continuous t vs y curve. I tried deval but for that i need redefine a DE everytime as sol1, sol2 and so on for finding out the required initial value. Is there any way to find out the point solution of DE without any more substituion?