scipy.fftpack.sc_diff#
- scipy.fftpack.sc_diff(x, a, b, period=None, _cache={})[source]#
Return (a,b)-sinh/cosh 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 = sqrt(-1)*sinh(j*a*2*pi/period)/cosh(j*b*2*pi/period) * x_j y_0 = 0
- Parameters
- xarray_like
Input array.
- a,bfloat
Defines the parameters of the sinh/cosh pseudo-differential operator.
- periodfloat, optional
The period of the sequence x. Default is 2*pi.
Notes
sc_diff(cs_diff(x,a,b),b,a) == xFor evenlen(x), the Nyquist mode of x is taken as zero.