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scipy tutorial - Baustatik-Info-Server

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Return k-th derivative (or integral) of a periodic sequence x.<br />

If x_j and y_j are Fourier coefficients of periodic functions x and y, respectively, then<br />

y_j = pow(sqrt(-1)*j*2*pi/period, order) * x_j y_0 = 0 if order is not 0.<br />

Optional input:<br />

Notes:<br />

SciPy Reference Guide, Release 0.8.dev<br />

order<br />

The order of differentiation. Default order is 1. If order is negative, then integration is carried out<br />

under the assumption that x_0==0.<br />

period<br />

The assumed period of the sequence. Default is 2*pi.<br />

If sum(x,axis=0)=0 then<br />

diff(diff(x,k),-k)==x (within numerical accuracy)<br />

For odd order and even len(x), the Nyquist mode is taken zero.<br />

tilbert(x, h, period=None, _cache={})<br />

tilbert(x, h, period=2*pi) -> y<br />

Return h-Tilbert transform of a periodic sequence x.<br />

If x_j and y_j are Fourier coefficients of periodic functions x and y, respectively, then<br />

Input:<br />

Notes:<br />

y_j = sqrt(-1)*coth(j*h*2*pi/period) * x_j y_0 = 0<br />

h<br />

Defines the parameter of the Tilbert transform.<br />

period<br />

The assumed period of the sequence. Default period is 2*pi.<br />

If sum(x,axis=0)==0 and n=len(x) is odd then<br />

tilbert(itilbert(x)) == x<br />

If 2*pi*h/period is approximately 10 or larger then numerically<br />

tilbert == hilbert<br />

(theoretically oo-Tilbert == Hilbert). For even len(x), the Nyquist mode of x is taken zero.<br />

itilbert(x, h, period=None, _cache={})<br />

itilbert(x, h, period=2*pi) -> y<br />

Return inverse h-Tilbert transform of a periodic sequence x.<br />

If x_j and y_j are Fourier coefficients of periodic functions x and y, respectively, then<br />

y_j = -sqrt(-1)*tanh(j*h*2*pi/period) * x_j y_0 = 0<br />

Optional input: see tilbert.__doc__<br />

3.3. Fourier transforms (<strong>scipy</strong>.fftpack) 171

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