scipy tutorial - Baustatik-Info-Server

3.13.8 Waveforms
SciPy Reference Guide, Release 0.8.dev
sawtooth(t[, width]) Returns a periodic sawtooth waveform with period 2*pi
square(t[, duty]) Returns a periodic square-wave waveform with period 2*pi
gausspulse(t[, fc, bw, bwr, tpr, retquad, ...]) Return a gaussian modulated sinusoid: exp(-a t^2) exp(1j*2*pi*fc)
chirp(t[, f0, t1, f1, method, phi, qshape]) Frequency-swept cosine generator.
sawtooth(t, width=1)
Returns a periodic sawtooth waveform with period 2*pi which rises from -1 to 1 on the interval 0 to width*2*pi
and drops from 1 to -1 on the interval width*2*pi to 2*pi width must be in the interval [0,1]
square(t, duty=0.5)
Returns a periodic square-wave waveform with period 2*pi which is +1 from 0 to 2*pi*duty and -1 from
2*pi*duty to 2*pi duty must be in the interval [0,1]
gausspulse(t, fc=1000, bw=0.5, bwr=-6, tpr=-60, retquad=0, retenv=0)
Return a gaussian modulated sinusoid: exp(-a t^2) exp(1j*2*pi*fc)
If retquad is non-zero, then return the real and imaginary parts
(inphase and quadrature)
If retenv is non-zero, then return the envelope (unmodulated signal). Otherwise, return the real part of the
modulated sinusoid.
Inputs:
t – Input array. fc – Center frequency (Hz). bw – Fractional bandwidth in frequency domain of
pulse (Hz). bwr – Reference level at which fractional bandwidth is calculated (dB). tpr – If t is
‘cutoff’, then the function returns the cutoff time for when the
pulse amplitude falls below tpr (in dB).
retquad – Return the quadrature (imaginary) as well as the real part of the signal retenv – Return
the envelope of th signal.
chirp(t, f0=0, t1=1, f1=100, method=’linear’, phi=0, qshape=None)
Frequency-swept cosine generator.
Parameters
t : ndarray
Times at which to evaluate the waveform.
f0 : float or ndarray, optional
Frequency (in Hz) of the waveform at time 0. If f0 is an ndarray, it specifies the
frequency change as a polynomial in t (see Notes below).
t1 : float, optional
Time at which f1 is specified.
f1 : float, optional
Frequency (in Hz) of the waveform at time t1.
method : {‘linear’, ‘quadratic’, ‘logarithmic’}, optional
Kind of frequency sweep.
phi : float
Phase offset, in degrees.
qshape : {‘convex’, ‘concave’}
3.13. Signal processing (scipy.signal) 345