mirror of
https://github.com/wassname/simpeg.git
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Brendan Smithyman
24 lines
725 B
Python
24 lines
725 B
Python
from __future__ import division
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from __future__ import unicode_literals
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from __future__ import print_function
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from __future__ import absolute_import
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from future import standard_library
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standard_library.install_aliases()
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from past.utils import old_div
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import numpy as np
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from scipy.constants import mu_0, epsilon_0
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# useful params
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def omega(freq):
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"""Angular frequency, omega"""
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return 2.*np.pi*freq
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def k(freq, sigma, mu=mu_0, eps=epsilon_0):
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""" Eq 1.47 - 1.49 in Ward and Hohmann """
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w = omega(freq)
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alp = w * np.sqrt( mu*eps/2 * ( np.sqrt(1. + (old_div(sigma, (eps*w)))**2 ) + 1) )
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beta = w * np.sqrt( mu*eps/2 * ( np.sqrt(1. + (old_div(sigma, (eps*w)))**2 ) - 1) )
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return alp - 1j*beta
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