From 78d7a2d6a4ccd04dd3bb734f6d21b937c5839403 Mon Sep 17 00:00:00 2001 From: "W. Trevor King" Date: Tue, 27 Mar 2012 13:11:01 -0400 Subject: [PATCH] Add vibration_analyze.breit_wigner_resonant_frequency(). Now people using the module don't have to think or read comments to determine the resonant frequency from fitted parameters ;). --- calibcant/vibration_analyze.py | 10 +++++++--- 1 file changed, 7 insertions(+), 3 deletions(-) diff --git a/calibcant/vibration_analyze.py b/calibcant/vibration_analyze.py index 1844dcf..a1125b6 100644 --- a/calibcant/vibration_analyze.py +++ b/calibcant/vibration_analyze.py @@ -454,6 +454,11 @@ def breit_wigner_area(A, B, C): # = (pi*C) / (2*B*A**2) return (_numpy.pi * C) / (2 * B * A**2) +def breit_wigner_resonant_frequency(A, B): + if (B**2 >= 2*A**2): + return 0 # over- or critically-damped + return _numpy.sqrt(A**2 - B**2/2) + def save(filename, group='/', raw=None, config=None, deflection_channel_config=None, processed=None): specs = [ @@ -543,9 +548,8 @@ def plot(deflection=None, freq_axis=None, power=None, A=None, B=None, freq_axes.plot(freq_axis, fitdata, 'b-') noisefloor = D + 0*freq_axis; freq_axes.plot(freq_axis, noisefloor) - - if B**2 < 2*A**2: - res_freq = _numpy.sqrt(A**2 - B**2/2) + res_freq = breit_wigner_resonant_frequency(A=A, B=B) + if res_freq > 0: freq_axes.axvline(res_freq, color='b', zorder=-1) freq_axes.set_title('power spectral density %s' % timestamp) -- 2.26.2