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@ -57,7 +57,7 @@ def sech(x):
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def _gengamspec(wn, N=5, M=4):
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''' Return Generalized gamma spectrum in dimensionless form
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""" Return Generalized gamma spectrum in dimensionless form
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Parameters
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----------
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@ -106,7 +106,7 @@ def _gengamspec(wn, N=5, M=4):
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Torsethaugen, K. (2004)
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"Simplified Double Peak Spectral Model for Ocean Waves"
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In Proc. 14th ISOPE
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'''
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"""
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w = atleast_1d(wn)
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S = zeros_like(w)
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@ -132,7 +132,7 @@ class ModelSpectrum(object):
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self.type = 'ModelSpectrum'
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def tospecdata(self, w=None, wc=None, nw=257):
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'''
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"""
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Return SpecData1D object from ModelSpectrum
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Parameter
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@ -148,7 +148,7 @@ class ModelSpectrum(object):
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-------
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S : SpecData1D object
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member attributes of model spectrum are copied to S.workspace
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'''
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"""
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if w is None:
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if wc is None:
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@ -165,8 +165,8 @@ class ModelSpectrum(object):
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return S
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def chk_seastate(self):
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''' Check if seastate is valid
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'''
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""" Check if seastate is valid
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"""
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if self.Hm0 < 0:
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raise ValueError('Hm0 can not be negative!')
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@ -185,7 +185,7 @@ class ModelSpectrum(object):
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class Bretschneider(ModelSpectrum):
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'''
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"""
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Bretschneider spectral density model
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Member variables
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@ -237,7 +237,7 @@ class Bretschneider(ModelSpectrum):
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--------
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Jonswap,
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Torsethaugen
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'''
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"""
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def __init__(self, Hm0=7.0, Tp=11.0, N=5, M=4, chk_seastate=True, **kwds):
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self.type = 'Bretschneider'
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@ -249,8 +249,8 @@ class Bretschneider(ModelSpectrum):
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self.chk_seastate()
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def __call__(self, wi):
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''' Return Bretschnieder spectrum
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'''
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""" Return Bretschnieder spectrum
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"""
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w = atleast_1d(wi)
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if self.Hm0 > 0:
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wp = 2 * pi / self.Tp
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@ -262,7 +262,7 @@ class Bretschneider(ModelSpectrum):
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def jonswap_peakfact(Hm0, Tp):
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''' Jonswap peakedness factor, gamma, given Hm0 and Tp
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""" Jonswap peakedness factor, gamma, given Hm0 and Tp
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Parameters
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----------
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@ -313,7 +313,7 @@ def jonswap_peakfact(Hm0, Tp):
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See also
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--------
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jonswap
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'''
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"""
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Hm0, Tp = atleast_1d(Hm0, Tp)
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x = Tp / sqrt(Hm0)
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@ -332,7 +332,7 @@ def jonswap_peakfact(Hm0, Tp):
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def jonswap_seastate(u10, fetch=150000., method='lewis', g=9.81,
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output='dict'):
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'''
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"""
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Return Jonswap seastate from windspeed and fetch
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Parameters
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@ -400,7 +400,7 @@ def jonswap_seastate(u10, fetch=150000., method='lewis', g=9.81,
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A parametric wave prediction model.
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J. phys. oceanogr. Vol 6, pp 200-228
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'''
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"""
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# The following formulas are from Lewis and Allos 1990:
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zeta = g * fetch / (u10 ** 2) # dimensionless fetch, Table 1
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@ -440,7 +440,7 @@ def jonswap_seastate(u10, fetch=150000., method='lewis', g=9.81,
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class Jonswap(ModelSpectrum):
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'''
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"""
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Jonswap spectral density model
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Member variables
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@ -520,7 +520,7 @@ class Jonswap(ModelSpectrum):
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Measurements of Wind-Wave Growth and Swell Decay during the Joint
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North Sea Project (JONSWAP).
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Ergansungsheft, Reihe A(8), Nr. 12, Deutschen Hydrografischen Zeitschrift.
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'''
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"""
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def __init__(self, Hm0=7.0, Tp=11.0, gamma=None, sigmaA=0.07, sigmaB=0.09,
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Ag=None, N=5, M=4, method='integration', wnc=6.0,
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@ -552,17 +552,17 @@ class Jonswap(ModelSpectrum):
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gam = self.gamma
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outsideJonswapRange = Tp > 5 * sqrt(Hm0) or Tp < 3.6 * sqrt(Hm0)
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if outsideJonswapRange:
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txt0 = '''
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txt0 = """
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Hm0=%g,Tp=%g is outside the JONSWAP range.
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The validity of the spectral density is questionable.
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''' % (Hm0, Tp)
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""" % (Hm0, Tp)
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warnings.warn(txt0)
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if gam < 1 or 7 < gam:
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txt = '''
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txt = """
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The peakedness factor, gamma, is possibly too large.
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The validity of the spectral density is questionable.
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'''
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"""
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warnings.warn(txt)
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def _localspec(self, wn):
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@ -617,8 +617,8 @@ class Jonswap(ModelSpectrum):
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self.Ag = 1.0 / area
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def _pre_calculate_ag(self):
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''' PRECALCULATEAG Precalculate normalization.
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'''
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""" PRECALCULATEAG Precalculate normalization.
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"""
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if self.gamma == 1:
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self.Ag = 1.0
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self.method = 'parametric'
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@ -631,8 +631,8 @@ class Jonswap(ModelSpectrum):
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norm_ag()
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def peak_e_factor(self, wn):
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''' PEAKENHANCEMENTFACTOR
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'''
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""" PEAKENHANCEMENTFACTOR
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"""
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w = maximum(atleast_1d(wn), 0.0)
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sab = where(w > 1, self.sigmaB, self.sigmaA)
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@ -641,8 +641,8 @@ class Jonswap(ModelSpectrum):
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return Gf
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def __call__(self, wi):
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''' JONSWAP spectral density
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'''
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""" JONSWAP spectral density
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"""
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w = atleast_1d(wi)
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if (self.Hm0 > 0.0):
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@ -660,7 +660,7 @@ class Jonswap(ModelSpectrum):
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def phi1(wi, h, g=9.81):
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''' Factor transforming spectra to finite water depth spectra.
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""" Factor transforming spectra to finite water depth spectra.
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Input
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-----
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@ -692,7 +692,7 @@ def phi1(wi, h, g=9.81):
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1 spectral form.'
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J. Geophys. Res., Vol 90, No. C1, pp 975-986
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'''
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"""
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w = atleast_1d(wi)
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if h == inf: # % special case infinite water depth
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return ones_like(w)
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@ -709,7 +709,7 @@ def phi1(wi, h, g=9.81):
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class Tmaspec(Jonswap):
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''' JONSWAP spectrum for finite water depth
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""" JONSWAP spectrum for finite water depth
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Member variables
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----------------
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@ -783,7 +783,7 @@ class Tmaspec(Jonswap):
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Ergansungsheft, Reihe A(8), Nr. 12, deutschen Hydrografischen
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Zeitschrift.
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'''
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"""
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def __init__(self, Hm0=7.0, Tp=11.0, gamma=None, sigmaA=0.07, sigmaB=0.09,
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Ag=None, N=5, M=4, method='integration', wnc=6.0,
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@ -808,7 +808,7 @@ class Tmaspec(Jonswap):
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class Torsethaugen(ModelSpectrum):
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'''
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"""
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Torsethaugen double peaked (swell + wind) spectrum model
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Member variables
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@ -881,7 +881,7 @@ class Torsethaugen(ModelSpectrum):
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'A two peak wave spectral model.'
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In proceedings OMAE, Glasgow
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'''
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"""
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def __init__(self, Hm0=7, Tp=11, method='integration', wnc=6, gravity=9.81,
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chk_seastate=True, **kwds):
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@ -899,26 +899,26 @@ class Torsethaugen(ModelSpectrum):
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self._init_spec()
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def __call__(self, w):
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''' TORSETHAUGEN spectral density
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'''
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""" TORSETHAUGEN spectral density
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"""
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return self.wind(w) + self.swell(w)
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def _chk_extra_param(self):
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Hm0 = self.Hm0
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Tp = self.Tp
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if Hm0 > 11 or Hm0 > max((Tp / 3.6) ** 2, (Tp - 2) * 12 / 11):
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txt0 = '''Hm0 is outside the valid range.
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The validity of the spectral density is questionable'''
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txt0 = """Hm0 is outside the valid range.
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The validity of the spectral density is questionable"""
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warnings.warn(txt0)
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if Tp > 20 or Tp < 3:
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txt1 = '''Tp is outside the valid range.
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The validity of the spectral density is questionable'''
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txt1 = """Tp is outside the valid range.
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The validity of the spectral density is questionable"""
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warnings.warn(txt1)
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def _init_spec(self):
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''' Initialize swell and wind part of Torsethaugen spectrum
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'''
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""" Initialize swell and wind part of Torsethaugen spectrum
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"""
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monitor = 0
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Hm0 = self.Hm0
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Tp = self.Tp
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@ -1050,7 +1050,7 @@ class Torsethaugen(ModelSpectrum):
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class McCormick(Bretschneider):
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''' McCormick spectral density model
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""" McCormick spectral density model
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Member variables
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----------------
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@ -1095,7 +1095,7 @@ class McCormick(Bretschneider):
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|
M.E. McCormick (1999)
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"Application of the Generic Spectral Formula to Fetch-Limited Seas"
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|
|
Marine Technology Society, Vol 33, No. 3, pp 27-32
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'''
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"""
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def __init__(self, Hm0=7, Tp=11, Tz=None, M=None, chk_seastate=True):
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self.type = 'McCormick'
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|
@ -1122,7 +1122,7 @@ class McCormick(Bretschneider):
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class OchiHubble(ModelSpectrum):
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''' OchiHubble bimodal spectral density model.
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""" OchiHubble bimodal spectral density model.
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Member variables
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----------------
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@ -1171,7 +1171,7 @@ class OchiHubble(ModelSpectrum):
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'On six-parameter wave spectra.'
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|
|
In Proc. 15th Conf. Coastal Engng., Vol.1, pp301-328
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'''
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"""
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|
def __init__(self, Hm0=7, par=1, chk_seastate=True):
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self.type = 'Ochi Hubble'
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|
@ -1253,7 +1253,7 @@ class OchiHubble(ModelSpectrum):
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class Wallop(Bretschneider):
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'''Wallop spectral density model.
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"""Wallop spectral density model.
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Member variables
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----------------
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@ -1304,7 +1304,7 @@ class Wallop(Bretschneider):
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|
|
Huang, N.E., Long, S.R., Tung, C.C, Yuen, Y. and Bilven, L.F. (1981)
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"A unified two parameter wave spectral model for a generous sea state"
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|
|
J. Fluid Mechanics, Vol.112, pp 203-224
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|
|
'''
|
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"""
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|
|
def __init__(self, Hm0=7, Tp=11, N=None, chk_seastate=True):
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|
|
self.type = 'Wallop'
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|
|
@ -1325,7 +1325,7 @@ class Wallop(Bretschneider):
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class Spreading(object):
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|
'''
|
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"""
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|
|
Directional spreading function.
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Parameters
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@ -1488,7 +1488,7 @@ class Spreading(object):
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NB! The generally strong frequency dependence in directional spread
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makes it questionable to run load tests of ships and structures with a
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directional spread independent of frequency (Krogstad and Barstow, 1999).
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'''
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"""
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# Parameterization of B
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# def = 2 Donelan et al freq. parametrization for 'sech2'
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# def = 3 Banner freq. parametrization for 'sech2'
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@ -1560,10 +1560,10 @@ class Spreading(object):
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return atleast_1d(self.theta0).flatten()
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def chk_input(self, theta, w=1, wc=1):
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''' CHK_INPUT
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""" CHK_INPUT
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CALL [s_par,TH,phi0,Nt] = inputchk(theta,w,wc)
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'''
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"""
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wn = atleast_1d(w / wc)
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theta = theta.ravel()
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@ -1579,7 +1579,7 @@ class Spreading(object):
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return s, TH, phi0, Nt
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def cos2s(self, theta, w=1, wc=1): # [D, phi0] =
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''' COS2S spreading function
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""" COS2S spreading function
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cos2s(theta,w) = N(S)*[cos((theta-theta0)/2)]^(2*S) (0 < S)
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@ -1599,7 +1599,7 @@ class Spreading(object):
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The principal direction of D is always along the x-axis.
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phi0 : real scalar
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Parameter defining the actual principal direction of D.
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'''
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"""
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S, TH, phi0 = self.chk_input(theta, w, wc)[:3]
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gammaln = sp.gammaln
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@ -1609,7 +1609,7 @@ class Spreading(object):
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return D, phi0
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def poisson(self, theta, w=1, wc=1): # [D,phi0] =
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''' POISSON spreading function
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""" POISSON spreading function
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poisson(theta,w) = N(X)/(1-2*X*cos(theta-theta0)+X^2) (0 < X < 1)
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@ -1629,14 +1629,14 @@ class Spreading(object):
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The principal direction of D is always along the x-axis.
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phi0 : real scalar
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Parameter defining the actual principal direction of D.
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'''
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"""
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X, TH, phi0 = self.chk_input(theta, w, wc)[:3]
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D = (1 - X ** 2.) / (1. - (2. * cos(TH) - X) * X) / (2. * pi)
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return D, phi0
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def wrap_norm(self, theta, w=1, wc=1):
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''' Wrapped Normal spreading function
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""" Wrapped Normal spreading function
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wnormal(theta,w) = N(D1)*[1 +
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2*sum exp(-(n*D1)^2/2)*cos(n*(theta-theta0))] (0 < D1)
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@ -1657,7 +1657,7 @@ class Spreading(object):
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The principal direction of D is always along the x-axis.
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phi0 : real scalar
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Parameter defining the actual principal direction of D.
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'''
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"""
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par, TH, phi0, Nt = self.chk_input(theta, w, wc)
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@ -1678,7 +1678,7 @@ class Spreading(object):
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return D, phi0
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def sech2(self, theta, w=1, wc=1):
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'''SECH2 directonal spreading function
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"""SECH2 directonal spreading function
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sech2(theta,w) = N(B)*0.5*B*sech(B*(theta-theta0))^2 (0 < B)
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@ -1698,7 +1698,7 @@ class Spreading(object):
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The principal direction of D is always along the x-axis.
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phi0 : real scalar
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Parameter defining the actual principal direction of D.
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'''
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"""
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B, TH, phi0 = self.chk_input(theta, w, wc)[:3]
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NB = tanh(pi * B) # % Normalization factor.
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@ -1708,7 +1708,7 @@ class Spreading(object):
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return D, phi0
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def mises(self, theta, w=1, wc=1):
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'''Mises spreading function
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"""Mises spreading function
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mises(theta,w) = N(K)*exp(K*cos(theta-theta0)) (0 < K)
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@ -1728,7 +1728,7 @@ class Spreading(object):
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The principal direction of D is always along the x-axis.
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phi0 : real scalar
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Parameter defining the actual principal direction of D.
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'''
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"""
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K, TH, phi0 = self.chk_input(theta, w, wc)[:3]
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@ -1736,7 +1736,7 @@ class Spreading(object):
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return D, phi0
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def box(self, theta, w=1, wc=1):
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''' Box car spreading function
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""" Box car spreading function
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box(theta,w) = N(A)*I( -A < theta-theta0 < A) (0 < A < pi)
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@ -1756,7 +1756,7 @@ class Spreading(object):
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The principal direction of D is always along the x-axis.
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phi0 : real scalar
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Parameter defining the actual principal direction of D.
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'''
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"""
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A, TH, phi0 = self.chk_input(theta, w, wc)[:3]
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D = ((-A <= TH) & (TH <= A)) / (2. * A)
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@ -1765,7 +1765,7 @@ class Spreading(object):
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# Local sub functions
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def fourier2distpar(self, r1):
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''' Fourier coefficients to distribution parameter
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""" Fourier coefficients to distribution parameter
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Parameters
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----------
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@ -1790,14 +1790,14 @@ class Spreading(object):
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Poisson spreading : R1 = X
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sech-2 spreading : R1 = pi/(2*B*sinh(pi/(2*B))
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Wrapped Normal : R1 = exp(-D1^2/2)
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'''
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"""
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fourierfun = self._fourierdispatch.get(self.type[0])
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return fourierfun(r1)
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@staticmethod
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def fourier2x(r1):
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''' Returns the solution of r1 = x.
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'''
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""" Returns the solution of r1 = x.
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"""
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X = r1
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if any(X >= 1):
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raise ValueError('POISSON spreading: X value must be less than 1')
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@ -1805,8 +1805,8 @@ class Spreading(object):
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@staticmethod
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def fourier2a(r1):
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''' Returns the solution of R1 = sin(A)/A.
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'''
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""" Returns the solution of R1 = sin(A)/A.
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"""
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A0 = flipud(linspace(0, pi + 0.1, 1025))
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funA = interp1d(sinc(A0 / pi), A0)
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A0 = funA(r1.ravel())
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@ -1837,9 +1837,9 @@ class Spreading(object):
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@staticmethod
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def fourier2k(r1):
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'''
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"""
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Returns the solution of R1 = besseli(1,K)/besseli(0,K),
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'''
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"""
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def fun0(x):
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return sp.ive(1, x) / sp.ive(0, x)
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@ -1858,8 +1858,8 @@ class Spreading(object):
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return K
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def fourier2b(self, r1):
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''' Returns the solution of R1 = pi/(2*B*sinh(pi/(2*B)).
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'''
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""" Returns the solution of R1 = pi/(2*B*sinh(pi/(2*B)).
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"""
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B0 = hstack((linspace(_EPS, 5, 513), linspace(5.0001, 100)))
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funB = interp1d(self._r1ofsech2(B0), B0)
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@ -1879,8 +1879,8 @@ class Spreading(object):
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return B
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def fourier2d(self, r1):
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''' Returns the solution of R1 = exp(-D**2/2).
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'''
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""" Returns the solution of R1 = exp(-D**2/2).
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"""
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r = clip(r1, 0., 1.0)
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return where(r <= 0, inf, sqrt(-2.0 * log(r)))
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@ -1936,7 +1936,7 @@ class Spreading(object):
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return atleast_1d(self.s_a)
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def spread_parameter_s(self, wn):
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''' Return spread parameter, S, equivalent for the COS2S function
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""" Return spread parameter, S, equivalent for the COS2S function
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Parameters
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----------
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@ -1947,7 +1947,7 @@ class Spreading(object):
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-------
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S : ndarray
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spread parameter of COS2S functions
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'''
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"""
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spread = dict(b=self._banner_spread,
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d=self._donelan_spread,
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@ -1972,14 +1972,14 @@ class Spreading(object):
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@staticmethod
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def _donelan(wn):
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''' High frequency decay of B of sech2 paramater
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'''
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""" High frequency decay of B of sech2 paramater
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"""
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return 10.0 ** (-0.4 + 0.8393 * exp(-0.567 * log(wn ** 2)))
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@staticmethod
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def _r1ofsech2(B):
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''' R1OFSECH2 Computes R1 = pi./(2*B.*sinh(pi./(2*B)))
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'''
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""" R1OFSECH2 Computes R1 = pi./(2*B.*sinh(pi./(2*B)))
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"""
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realmax = finfo(float).max
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tiny = 1. / realmax
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x = clip(2. * B, tiny, realmax)
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@ -1988,7 +1988,7 @@ class Spreading(object):
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-2. * xk / (exp(xk) * expm1(-2. * xk)))
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def tospecdata2d(self, specdata=None, theta=None, wc=0.52, nt=51):
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'''
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"""
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MKDSPEC Make a directional spectrum
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frequency spectrum times spreading function
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@ -2020,7 +2020,7 @@ class Spreading(object):
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h = SD.plot()
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See also spreading, rotspec, jonswap, torsethaugen
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'''
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"""
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if specdata is None:
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specdata = Jonswap().tospecdata()
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