Marginal changes.

This commit is contained in:
Ludger Küperkoch 2015-07-01 15:31:50 +02:00
parent 5bb616ffc5
commit 3e81adfec6

View File

@ -13,8 +13,6 @@ import scipy as sc
import matplotlib.pyplot as plt
from obspy.core import Stream, UTCDateTime
import warnings
import pdb
def earllatepicker(X, nfac, TSNR, Pick1, iplot=None):
'''
@ -257,6 +255,8 @@ def fmpicker(Xraw, Xfilt, pickwin, Pick, iplot=None):
elif P1[0] > 0 and P2[0] <= 0:
FM = '+'
print 'fmpicker: Found polarity %s' % FM
if iplot > 1:
plt.figure(iplot)
plt.subplot(2, 1, 1)
@ -301,48 +301,34 @@ def crossings_nonzero_all(data):
return ((pos[:-1] & npos[1:]) | (npos[:-1] & pos[1:])).nonzero()[0]
def getSNR(st, TSNR, t0):
"""
returns the maximum signal to noise ratio SNR (also in dB) and the
corresponding noise level for a given data stream ST ,initial time T0 and
time window parameter tuple TSNR
def getSNR(X, TSNR, t1):
'''
Function to calculate SNR of certain part of seismogram relative to
given time (onset) out of given noise and signal windows. A safety gap
between noise and signal part can be set. Returns SNR and SNR [dB] and
noiselevel.
:param: st, time series (seismogram)
:param: X, time series (seismogram)
:type: `~obspy.core.stream.Stream`
:param: TSNR, length of time windows [s] around t0 (onset) used to determine
SNR
:param: TSNR, length of time windows [s] around t1 (onset) used to determine SNR
:type: tuple (T_noise, T_gap, T_signal)
:param: t0, initial time (onset) from which noise and signal windows are calculated
:param: t1, initial time (onset) from which noise and signal windows are calculated
:type: float
:return: SNR, SNRdB, noiselevel
'''
..examples:
assert isinstance(X, Stream), "%s is not a stream object" % str(X)
>>> from obspy.core import read
>>> st = read()
>>> result = getSNR(st, (6., .3, 3.), 4.67)
>>> print result
(5.1267717641040758, 7.0984398375666435, 132.89370192191919)
>>> result = getSNR(st, (8., .2, 5.), 4.67)
>>> print result
(4.645441835797703, 6.6702702677384131, 133.03562794665109)
"""
assert isinstance(st, Stream), "%s is not a stream object" % str(st)
SNR = None
noiselevel = None
for tr in st:
x = tr.data
t = np.arange(0, tr.stats.npts / tr.stats.sampling_rate,
tr.stats.delta)
x = X[0].data
t = np.arange(0, X[0].stats.npts / X[0].stats.sampling_rate,
X[0].stats.delta)
# get noise window
inoise = getnoisewin(t, t0, TSNR[0], TSNR[1])
inoise = getnoisewin(t, t1, TSNR[0], TSNR[1])
# get signal window
isignal = getsignalwin(t, t0, TSNR[2])
isignal = getsignalwin(t, t1, TSNR[2])
if np.size(inoise) < 1:
print 'getSNR: Empty array inoise, check noise window!'
return
@ -354,18 +340,9 @@ def getSNR(st, TSNR, t0):
x = x - np.mean(x[inoise])
# calculate ratios
new_noiselevel = np.sqrt(np.mean(np.square(x[inoise])))
noiselevel = np.sqrt(np.mean(np.square(x[inoise])))
signallevel = np.sqrt(np.mean(np.square(x[isignal])))
newSNR = signallevel / new_noiselevel
if not SNR or newSNR > SNR:
SNR = newSNR
noiselevel = new_noiselevel
if not SNR or not noiselevel:
raise ValueError('signal to noise ratio could not be calculated:\n'
'noiselevel: {0}\n'
'SNR: {1}'.format(noiselevel, SNR))
SNR = signallevel / noiselevel
SNRdB = 10 * np.log10(SNR)
return SNR, SNRdB, noiselevel
@ -496,6 +473,7 @@ def wadaticheck(pickdic, dttolerance, iplot):
Spicks.append(UTCSpick.timestamp)
SPtimes.append(spt)
if len(SPtimes) >= 3:
# calculate slope
p1 = np.polyfit(Ppicks, SPtimes, 1)
@ -527,8 +505,7 @@ def wadaticheck(pickdic, dttolerance, iplot):
checkedPpicks.append(checkedPpick.timestamp)
checkedSpick = UTCDateTime(pickdic[key]['S']['mpp'])
checkedSpicks.append(checkedSpick.timestamp)
checkedSPtime = pickdic[key]['S']['mpp'] - \
pickdic[key]['P']['mpp']
checkedSPtime = pickdic[key]['S']['mpp'] - pickdic[key]['P']['mpp']
checkedSPtimes.append(checkedSPtime)
pickdic[key]['S']['marked'] = marker
@ -563,8 +540,7 @@ def wadaticheck(pickdic, dttolerance, iplot):
plt.title('Wadati-Diagram, %d S-P Times, Vp/Vs(raw)=%5.2f,' \
'Vp/Vs(checked)=%5.2f' % (len(SPtimes), vpvsr, cvpvsr))
plt.legend([f1, f2, f3, f4], ['Skipped S-Picks', 'Wadati 1', \
'Reliable S-Picks', 'Wadati 2'],
loc='best')
'Reliable S-Picks', 'Wadati 2'], loc='best')
else:
plt.title('Wadati-Diagram, %d S-P Times' % len(SPtimes))
@ -649,8 +625,7 @@ def checksignallength(X, pick, TSNR, minsiglength, nfac, minpercent, iplot):
[minsiglevel, minsiglevel], 'g')
p5, = plt.plot([pick, pick], [min(x), max(x)], 'b', linewidth=2)
plt.legend([p1, p2, p3, p4, p5], ['Data', 'Envelope Noise Window', \
'Envelope Signal Window',
'Minimum Signal Level', \
'Envelope Signal Window', 'Minimum Signal Level', \
'Onset'], loc='best')
plt.xlabel('Time [s] since %s' % X[0].stats.starttime)
plt.ylabel('Counts')
@ -713,8 +688,7 @@ def checkPonsets(pickdic, dttolerance, iplot):
badstations = np.array(stations)[ibad]
print 'checkPonset: Skipped %d P onsets out of %d' % (len(badstations) \
+ len(badjkstations),
len(stations))
+ len(badjkstations), len(stations))
goodmarker = 'goodPonsetcheck'
badmarker = 'badPonsetcheck'
@ -819,7 +793,108 @@ def jackknife(X, phi, h):
return PHI_jack, PHI_pseudo, PHI_sub
def checkZ4S(X, pick, zfac, checkwin, iplot):
'''
Function to compare energy content of vertical trace with
energy content of horizontal traces to detect spuriously
picked S onsets instead of P onsets. Usually, P coda shows
larger longitudal energy on vertical trace than on horizontal
traces, where the transversal energy is larger within S coda.
Be careful: there are special circumstances, where this is not
the case!
: param: X, fitered(!) time series, three traces
: type: `~obspy.core.stream.Stream`
: param: pick, initial (AIC) P onset time
: type: float
: param: zfac, factor for threshold determination,
vertical energy must exceed coda level times zfac
to declare a pick as P onset
: type: float
: param: checkwin, window length [s] for calculating P-coda
energy content
: type: float
: param: iplot, if iplot > 1, energy content and threshold
are shown
: type: int
'''
assert isinstance(X, Stream), "%s is not a stream object" % str(X)
print 'Check for spuriously picked S onset instead of P onset ...'
returnflag = 0
# split components
zdat = X.select(component="Z")
edat = X.select(component="E")
if len(edat) == 0: # check for other components
edat = X.select(component="2")
ndat = X.select(component="N")
if len(ndat) == 0: # check for other components
ndat = X.select(component="1")
z = zdat[0].data
tz = np.arange(0, zdat[0].stats.npts / zdat[0].stats.sampling_rate,
zdat[0].stats.delta)
# calculate RMS trace from vertical component
absz = np.sqrt(np.power(z, 2))
# calculate RMS trace from both horizontal traces
# make sure, both traces have equal lengths
lene = len(edat[0].data)
lenn = len(ndat[0].data)
minlen = min([lene, lenn])
absen = np.sqrt(np.power(edat[0].data[0:minlen - 1], 2) \
+ np.power(ndat[0].data[0:minlen - 1], 2))
# get signal window
isignal = getsignalwin(tz, pick, checkwin)
# calculate energy levels
zcodalevel = max(absz[isignal])
encodalevel = max(absen[isignal])
# calculate threshold
minsiglevel = encodalevel * zfac
# vertical P-coda level must exceed horizontal P-coda level
# zfac times encodalevel
if zcodalevel < minsiglevel:
print 'checkZ4S: Maybe S onset? Skip this P pick!'
else:
print 'checkZ4S: P onset passed checkZ4S test!'
returnflag = 1
if iplot > 1:
te = np.arange(0, edat[0].stats.npts / edat[0].stats.sampling_rate,
edat[0].stats.delta)
tn = np.arange(0, ndat[0].stats.npts / ndat[0].stats.sampling_rate,
ndat[0].stats.delta)
plt.plot(tz, z / max(z), 'k')
plt.plot(tz[isignal], z[isignal] / max(z), 'r')
plt.plot(te, edat[0].data / max(edat[0].data) + 1, 'k')
plt.plot(te[isignal], edat[0].data[isignal] / max(edat[0].data) + 1, 'r')
plt.plot(tn, ndat[0].data / max(ndat[0].data) + 2, 'k')
plt.plot(tn[isignal], ndat[0].data[isignal] / max(ndat[0].data) + 2, 'r')
plt.plot([tz[isignal[0]], tz[isignal[len(isignal) - 1]]], \
[minsiglevel / max(z), minsiglevel / max(z)], 'g', \
linewidth=2)
plt.xlabel('Time [s] since %s' % zdat[0].stats.starttime)
plt.ylabel('Normalized Counts')
plt.yticks([0, 1, 2], [zdat[0].stats.channel, edat[0].stats.channel, \
ndat[0].stats.channel])
plt.title('CheckZ4S, Station %s' % zdat[0].stats.station)
plt.show()
raw_input()
return returnflag
if __name__ == '__main__':
import doctest
doctest.testmod()