mirror of
https://github.com/wassname/simpeg.git
synced 2026-07-13 04:10:08 +08:00
D Fournier
cbe3b3de42
Add Mag Integral forward operator Begin Inversion script for magnetic integral
133 lines
3.9 KiB
Python
133 lines
3.9 KiB
Python
def fwr_MAG_F(mesh,B,M,rxLoc,flag):
|
|
"""
|
|
Forward model magnetic data using integral equation
|
|
|
|
INPUT:
|
|
mesh = Mesh in SimPEG format
|
|
B = Inducing field parameter [Binc, Bdecl, B0]
|
|
M = Magnetization information
|
|
[OPTIONS]
|
|
1- [Minc, Mdecl] : Assumes uniform magnetization orientation
|
|
2- [mx1,mx2,..., my1,...,mz1] : cell-based defined magnetization direction
|
|
3- diag(M): Block diagonal matrix with [Mx, My, Mz] along the diagonal
|
|
|
|
rxLox = Observation location informat [obsx, obsy, obsz]
|
|
|
|
flag = 'tmi' | 'xyz' | 'full'
|
|
[OPTIONS]
|
|
1- tmi : Magnetization direction used and data are projected onto the
|
|
inducing field direction F.shape([ndata, nc])
|
|
|
|
2- xyz : Magnetization direction used and data are given in 3-components
|
|
F.shape([3*ndata, nc])
|
|
|
|
3- full: Full tensor matrix stored with shape([3*ndata, 3*nc])
|
|
|
|
OUTPUT:
|
|
F = Linear forward modeling operation
|
|
|
|
Created on Dec, 20th 2015
|
|
|
|
@author: dominiquef
|
|
"""
|
|
|
|
#%%
|
|
from SimPEG import np, Utils, sp, mkvc
|
|
from get_T_mat import get_T_mat
|
|
|
|
|
|
xn = mesh.vectorNx;
|
|
yn = mesh.vectorNy;
|
|
zn = mesh.vectorNz;
|
|
|
|
mcell = (len(xn)-1) * (len(yn)-1) * (len(zn)-1)
|
|
|
|
ndata = rxLoc.shape[0]
|
|
|
|
#%% Create TMI projector
|
|
|
|
# Convert Bdecination from north to cartesian
|
|
D = (450.-float(B[1]))%360.
|
|
|
|
Ptmi = mkvc(np.r_[np.cos(np.deg2rad(B[0]))*np.cos(np.deg2rad(D)),
|
|
np.cos(np.deg2rad(B[0]))*np.sin(np.deg2rad(D)),
|
|
np.sin(np.deg2rad(B[0]))],2).T;
|
|
|
|
# Pre-allocate space
|
|
if flag=='tmi' | flag == 'xyz':
|
|
|
|
# If assumes uniform magnetization direction
|
|
if len(M) == 2:
|
|
|
|
# Convert declination from north to cartesian
|
|
Md = (450.-float(M[1]))%360.
|
|
|
|
# Create magnetization matrix
|
|
mx = np.cos(np.deg2rad(M[0])) * np.cos(np.deg2rad(Md))
|
|
my = np.cos(np.deg2rad(M[0])) * np.sin(np.deg2rad(Md))
|
|
mz = np.sin(np.deg2rad(M[0]))
|
|
|
|
Mx = Utils.sdiag(np.ones([mcell])*mx*B[2])
|
|
My = Utils.sdiag(np.ones([mcell])*my*B[2])
|
|
Mz = Utils.sdiag(np.ones([mcell])*mz*B[2])
|
|
|
|
Mxyz = sp.vstack((Mx,My,Mz));
|
|
|
|
# Otherwise if given a vector 3*ncells
|
|
elif len(M) == mesh.nC * 3:
|
|
|
|
Mxyz = sp.spdiags(M,0,mesh.nC * 3,mesh.nC * 3)
|
|
|
|
if flag == 'tmi':
|
|
F = np.zeros((ndata, mesh.nC))
|
|
|
|
elif flag == 'xyz':
|
|
F = np.zeros((int(3*ndata), mesh.nC))
|
|
|
|
elif flag == 'full':
|
|
F = np.zeros((int(3*ndata), int(3*mesh.nC)))
|
|
|
|
else:
|
|
print """Flag must be either 'tmi' | 'xyz' | 'full', please revised"""
|
|
return
|
|
|
|
|
|
# Loop through all observations and create forward operator (ndata-by-mcell)
|
|
print "Begin calculation of forward operator: " + flag
|
|
|
|
# Add counter to dsiplay progress. Good for large problems
|
|
progress = -1;
|
|
for ii in range(ndata):
|
|
|
|
tx, ty, tz = get_T_mat(xn,yn,zn,rxLoc[ii,:])
|
|
|
|
if flag=='tmi':
|
|
F[ii,:] = Ptmi.dot(np.vstack((tx,ty,tz)))*Mxyz
|
|
|
|
elif flag == 'xyz':
|
|
F[ii,:] = tx*Mxyz
|
|
F[ii+ndata,:] = ty*Mxyz
|
|
F[ii+2*ndata,:] = tz*Mxyz
|
|
|
|
elif flag == 'full':
|
|
F[ii,:] = tx
|
|
F[ii+ndata,:] = ty
|
|
F[ii+2*ndata,:] = tz
|
|
|
|
|
|
# Display progress
|
|
counter = np.floor(float(ii)/float(ndata)*10.);
|
|
|
|
if counter > progress:
|
|
|
|
arg = "Done " + str(counter*10) + " %"
|
|
print arg
|
|
progress = counter;
|
|
|
|
|
|
print "Done 100% ...forward modeling completed!!\n"
|
|
|
|
return F
|
|
|
|
|