using diff or gradient function normalized the vector

for some reason when i use gradient function over a vector the scale get lowerd for example of sin function: the maximum is divided by 10 and in other cases the maximum is divided by something else

Answer 1

[Jos]

you have to divide by the time step. For instance, this gives you what you want

dt=0.1;
t=-2*pi:dt:2*pi;
subplot(3,1,1)
plot(t,sin(t))
subplot(3,1,2)
plot(t,gradient(sin(t),dt))
subplot(3,1,3)
plot(t(1:end-1),diff(sin(t))/dt)