watex.externals.z.Z

class watex.externals.z.Z(z_array=None, z_err_array=None, freq=None)

Z class - generates an impedance tensor (Z) object.

Z is a complex array of the form (n_freq, 2, 2), with indices in the following order:

• Zxx: (0,0)

• Zxy: (0,1)

• Zyx: (1,0)

• Zyy: (1,1)

All errors are given as standard deviations (sqrt(VAR))

Parameters:

• z_array (numpy.ndarray(n_freq, 2, 2)) – array containing complex impedance values

• z_err_array (numpy.ndarray(n_freq, 2, 2)) – array containing error values (standard deviation) of impedance tensor elements

• freq (np.ndarray(n_freq)) – array of frequency values corresponding to impedance tensor elements.

Attributes	Description
freq	array of frequencies corresponding to elements of z
rotation_angle	angle of which data is rotated by
z	impedance tensor
z_err	estimated errors of impedance tensor
resistivity	apparent resisitivity estimated from z in Ohm-m
resistivity_err	apparent resisitivity error
phase	impedance phase (deg)
phase_err	error in impedance phase

Methods	Description
det	calculates determinant of z with errors
invariants	calculates the invariants of z
inverse	calculates the inverse of z
remove_distortion	removes distortion given a distortion matrix
remove_ss	removes static shift by assumin Z = S * Z_0
norm	calculates the norm of Z
only1d	zeros diagonal components and computes the absolute valued mean of the off-diagonal components.
only2d	zeros diagonal components
res_phase	computes resistivity and phase
rotate	rotates z positive clockwise, angle assumes North is 0.
set_res_phase	recalculates z and z_err, needs attribute freq
skew	calculates the invariant skew (off diagonal trace)
trace	calculates the trace of z

Example:

>>> import mtpy.core.z as mtz
>>> import numpy as np
>>> z_test = np.array([[0+0j, 1+1j], [-1-1j, 0+0j]])
>>> z_object = mtz.Z(z_array=z_test, freq=[1])
>>> z_object.rotate(45)
>>> z_object.resistivity