def test_phase_rad(sine_plus_impulse):
"""Test the function returning the phase of a signal in radians."""
phase = dsp.phase(sine_plus_impulse, deg=False, unwrap=False)
truth = np.angle(sine_plus_impulse.freq)
npt.assert_allclose(phase, truth, rtol=1e-10)
def _phase(signal, deg=False, unwrap=False, xscale='log', ax=None, **kwargs):
"""Plot the phase of the spectrum on the positive frequency axis."""
# check input
if not isinstance(signal, (Signal, FrequencyData)):
raise TypeError(
'Input data has to be of type: Signal or FrequencyData.')
_check_axis_scale(xscale)
# prepare figure
_, ax = _prepare_plot(ax)
# prepare input
kwargs = _return_default_colors_rgb(**kwargs)
phase_data = dsp.phase(signal, deg=deg, unwrap=unwrap)
# Construct the correct label string:
ylabel_string = 'Phase '
if unwrap == '360':
ylabel_string += '(wrapped to 360) '
elif unwrap is True:
ylabel_string += '(unwrapped) '
elif not isinstance(unwrap, bool):
raise ValueError(f"unwrap is {unwrap} but must be True, False, or 360")
if deg:
ylabel_string += 'in degree'
y_margin = 5
else:
ylabel_string += 'in radians'
# nice tick formatting is not done for unwrap=True. In this case
# it can create 1000 or more ticks.
if not unwrap or unwrap == "360":
ax.yaxis.set_major_locator(MultipleFractionLocator(np.pi, 2))
ax.yaxis.set_minor_locator(MultipleFractionLocator(np.pi, 6))
ax.yaxis.set_major_formatter(
MultipleFractionFormatter(nominator=1,
denominator=2,
base=np.pi,
base_str=r'\pi'))
y_margin = np.radians(5)
ymin = np.nanmin(phase_data) - y_margin # more elegant solution possible?
ymax = np.nanmax(phase_data) + y_margin
# prepare figure
ax.set_xlabel("Frequency in Hz")
ax.set_ylabel(ylabel_string)
ax.grid(True, 'both')
_set_axlim(ax, ax.set_xlim, _lower_frequency_limit(signal),
signal.frequencies[-1], ax.get_xlim())
_set_axlim(ax, ax.set_ylim, ymin, ymax, ax.get_ylim())
# plot data
if xscale == 'log':
ax.semilogx(signal.frequencies, phase_data.T, **kwargs)
else:
ax.plot(signal.frequencies, phase_data.T, **kwargs)
plt.tight_layout()
# set and format ticks
if xscale == 'log':
ax.xaxis.set_major_locator(LogLocatorITAToolbox())
ax.xaxis.set_major_formatter(LogFormatterITAToolbox())
return ax
def test_phase_deg_unwrap(sine_plus_impulse):
"""Test the function returning the unwrapped phase of a signal in deg."""
phase = dsp.phase(sine_plus_impulse, deg=True, unwrap=True)
truth = np.degrees(np.unwrap(np.angle(sine_plus_impulse.freq)))
npt.assert_allclose(phase, truth, rtol=1e-10)
