temp_int_odd= spline(time_even, temp_even, time_odd); 
temp_int_odd(length(time_odd)) = temp_even(length(time_even)); 
MSE = sum((temp_int_odd- temp_odd).^2)/length(temp_odd);
temp_int= zeros(1,24);
temp_int((0:2:22)+1) = temp_even; 
temp_int((1:2:23)+1) = temp_int_odd; 
figure
plot(0:23,temp,'-b',0:23,temp_int,'-r'); 
title('Hourly temperature variation')
xlabel('Time'); 
ylabel('Temperature (°C)'); 
legend('True','Cubicspline interpolation');