def recursive_sta_lta(a, nsta, nlta):
"""
Recursive STA/LTA.
Fast version written in C.
:note: This version directly uses a C version via CTypes
:type a: :class:`numpy.ndarray`, dtype=float64
:param a: Seismic Trace, numpy.ndarray dtype float64
:type nsta: int
:param nsta: Length of short time average window in samples
:type nlta: int
:param nlta: Length of long time average window in samples
:rtype: :class:`numpy.ndarray`, dtype=float64
:return: Characteristic function of recursive STA/LTA
.. seealso:: [Withers1998]_ (p. 98) and [Trnkoczy2012]_
"""
# be nice and adapt type if necessary
a = np.ascontiguousarray(a, np.float64)
ndat = len(a)
charfct = np.empty(ndat, dtype=np.float64)
# do not use pointer here:
clibsignal.recstalta(a, charfct, ndat, nsta, nlta)
return charfct
def recSTALTA(a, nsta, nlta):
"""
Recursive STA/LTA.
Fast version written in C.
:note: This version directly uses a C version via CTypes
:type a: numpy.ndarray dtype float64
:param a: Seismic Trace, numpy.ndarray dtype float64
:type nsta: Int
:param nsta: Length of short time average window in samples
:type nlta: Int
:param nlta: Length of long time average window in samples
:rtype: numpy.ndarray dtype float64
:return: Characteristic function of recursive STA/LTA
.. seealso:: [Withers1998]_ (p. 98) and [Trnkoczy2012]_
"""
# be nice and adapt type if necessary
a = np.require(a, 'float64', ['C_CONTIGUOUS'])
ndat = len(a)
charfct = np.empty(ndat, dtype='float64')
# do not use pointer here:
clibsignal.recstalta(a, charfct, ndat, nsta, nlta)
return charfct