Trigonometric

The amplitude is computed based on the following summation.

For Sine,

$$A(t)=\sum a_i\sin (i{\displaystyle \frac{2\pi }{T_0}}(t-t_0)=\sum a_i\sin (i{f}_0(t-t_0))\text{for}t>t_0.$$

For Cosine,

$$A(t)=\sum a_i\cos (i{\displaystyle \frac{2\pi }{T_0}}(t-t_0))=\sum a_i\cos (i{f}_0(t-t_0))\text{for}t>t_0.$$

In above equations, $T_0$ is the base period and $f_0$ is base frequency accordingly. In the above definition, $t_0$ is the (pseudo) start time of the step in which the amplitude is defined.

Syntax

amplitude Sine (1) (2) (3) [(4)...]
amplitude Cosine (1) (2) (3) [(4)...]
# (1) int, unique tag
# (2) double, base period T_0
# (3) double, amplitude at base period/frequency a_0
# [(4)...] double, optional amplitudes at higher periods a_i

Example

amplitude Sine 1 10. 2.

$$A(t)=2\sin ({\displaystyle \frac{\pi }{5}}(t-t_0)).$$

amplitude Sine 1 10. 2. 4.

$$A(t)=2\sin (0.2\pi (t-t_0))+4\sin (0.4\pi (t-t_0)).$$