Files
simpeg/SimPEG/MT/Utils/MT1Dsolutions.py
2016-07-17 16:02:43 -05:00

52 lines
1.6 KiB
Python

from __future__ import absolute_import
from __future__ import division
from __future__ import unicode_literals
from __future__ import print_function
from future import standard_library
standard_library.install_aliases()
import numpy as np, SimPEG as simpeg
from .MT1Danalytic import getEHfields
from scipy.constants import mu_0
def get1DEfields(m1d,sigma,freq,sourceAmp=1.0):
"""Function to get 1D electrical fields"""
# Get the gradient
G = m1d.nodalGrad
# Mass matrices
# Magnetic permeability
Mmu = simpeg.Utils.sdiag(m1d.vol*(old_div(1.0,mu_0)))
# Conductivity
Msig = m1d.getFaceInnerProduct(sigma)
# Set up the solution matrix
A = G.T*Mmu*G + 1j*2.*np.pi*freq*Msig
# Define the inner part of the solution matrix
Aii = A[1:-1,1:-1]
# Define the outer part of the solution matrix
Aio = A[1:-1,[0,-1]]
# Set the boundary conditions
Ed, Eu, Hd, Hu = getEHfields(m1d,sigma,freq,m1d.vectorNx)
Etot = (Ed + Eu)
if sourceAmp is not None:
Etot = ((old_div(Etot,Etot[-1]))*sourceAmp) # Scale the fields to be equal to sourceAmp at the top
## Note: The analytic solution is derived with e^iwt
bc = np.r_[Etot[0],Etot[-1]]
# The right hand side
rhs = Aio*bc
# Solve the system
Aii_inv = simpeg.Solver(Aii)
eii = Aii_inv*rhs
# Assign the boundary conditions
e = np.r_[bc[0],eii,bc[1]]
# Return the electrical fields
return e
if __name__ == '__main__':
hz = [(100.,18)]
M = simpeg.Mesh.TensorMesh([hz],'C')
sig = np.zeros(M.nC) + 1e-8
sig[M.vectorCCx<=0] = sigHalf