Improve type stability of basic sources

src/Blocks/sources.jl

@@ -237,15 +237,15 @@ Generate ramp signal.
  - `output`
 """
 @component function Ramp(; name,
- height = 1,
- duration = 1,
- offset = 0,
- start_time = 0,
+ height = 1.0,
+ duration = 1.0,
+ offset = 0.0,
+ start_time = 0.0,
  smooth = false)
  @named output = RealOutput()
  pars = @parameters offset=offset start_time=start_time height=height duration=duration
  equation = if smooth == false
- offset + ifelse(t < start_time, 0,
+ offset + ifelse(t < start_time, zero(height),
  ifelse(t < (start_time + duration), (t - start_time) * height / duration,
  height))
  else
@@ -320,20 +320,20 @@ Generate step signal.
 
  - `output`
 """
-@component function Step(; name, height = 1, offset = 0, start_time = 0, duration = Inf,
+@component function Step(; name, height = 1.0, offset = 0.0, start_time = 0.0, duration = Inf,
  smooth = 1e-5)
  @named output = RealOutput()
  duration_numeric = duration
  pars = @parameters offset=offset start_time=start_time height=height duration=duration
  equation = if smooth == false # use comparison in case smooth is a float
- offset + ifelse((start_time < t) & (t < start_time + duration), height, 0)
+ offset + ifelse((start_time < t) & (t < start_time + duration), height, zero(height))
  else
  smooth === true && (smooth = 1e-5)
  if duration_numeric == Inf
  smooth_step(t, smooth, height, offset, start_time)
  else
  smooth_step(t, smooth, height, offset, start_time) -
- smooth_step(t, smooth, height, 0, start_time + duration)
+ smooth_step(t, smooth, height, zero(start_time), start_time + duration)
  end
  end
 
@@ -366,17 +366,17 @@ Exponentially damped sine signal.
 """
 @component function ExpSine(; name,
  frequency,
- amplitude = 1,
+ amplitude = 1.0,
  damping = 0.1,
- phase = 0,
- offset = 0,
- start_time = 0,
+ phase = 0.0,
+ offset = 0.0,
+ start_time = 0.0,
  smooth = false)
  @named output = RealOutput()
  pars = @parameters offset=offset start_time=start_time amplitude=amplitude frequency=frequency phase=phase damping=damping
 
  equation = if smooth == false
- offset + ifelse(t < start_time, 0,
+ offset + ifelse(t < start_time, zero(amplitude),
  amplitude * exp(-damping * (t - start_time)) *
  sin(2 * pi * frequency * (t - start_time) + phase))
  else