def skin_kernel(alpha=0.0, length=601):
"""
Generates a skin effect kernel, with the specified parameters
kernel_step_function
heaviside(t+1)*(1-errf(alpha/21./np.sqrt(t+1)))
"""
t_kernel = np.arange(length)
if abs(alpha) > 0.0:
kernel_skineffect = kernel_generic2(htilde_skineffect, t_kernel, alpha)
else:
kernel_skineffect = np.zeros(length)
kernel_skineffect[0] = 1.0
return kernel_skineffect
def bounce_kernel(amp=0.02, time=4, length=601):
"""
Generates a bounce kernel, with the specified parameters.
kernel_step_function:
heaviside(t) + amp*heaviside(t-time)
"""
bounce = lambda t, amp, time: heaviside(t) - amp * np.double((t + 1) > time) * heaviside(t)
htilde_bounce = lambda t, time: bounce(t, amp, time) - bounce(t - 1, amp, time)
t_kernel = np.arange(length)
if abs(amp) > 0.0:
kernel_bounce = kernel_generic2(htilde_bounce, t_kernel, time)
else:
kernel_bounce = np.zeros(length)
kernel_bounce[0] = 1.0
return kernel_bounce
