Templated sine function with support for an offset level.
\f[
a sin(2 \pi f (t - t_0)) s + l
\f]
where
\vartable
symbol | Description | Data type
a | Amplitude | Function1<scalar>
f | Frequency [1/s] | Function1<scalar>
s | Type scale factor | Function1<Type>
l | Type offset level | Function1<Type>
t_0 | Start time [s] | scalar
t | Time [s] | scalar
\endvartable
Function1 is an abstract base-class of run-time selectable unary
functions which may be composed of other Function1's allowing the user
to specify complex functions of a single scalar variable, e.g. time.
The implementations need not be a simple or continuous functions;
interpolated tables and polynomials are also supported. In fact form of
mapping between a single scalar input and a single primitive type output
is supportable.
The primary application of Function1 is in time-varying boundary
conditions, it also used for other functions of time, e.g. injected mass
is spray simulations but is not limited to functions of time.
