scipy.fftpack.ss_diff¶
-
scipy.fftpack.
ss_diff
(x, a, b, period=None, _cache={})[source]¶ Return (a,b)-sinh/sinh pseudo-derivative of a periodic sequence x.
If x_j and y_j are Fourier coefficients of periodic functions x and y, respectively, then:
y_j = sinh(j*a*2*pi/period)/sinh(j*b*2*pi/period) * x_j y_0 = a/b * x_0
Parameters: x : array_like
The array to take the pseudo-derivative from.
a,b
Defines the parameters of the sinh/sinh pseudo-differential operator.
period : float, optional
The period of the sequence x. Default is
2*pi
.Notes
ss_diff(ss_diff(x,a,b),b,a) == x