ILSI.utils_stress

Functions

A_phi_(principal_stresses, principal_directions)	Compute A_phi as defined by Simpson 1997.
R_(principal_stresses)	Computes the shape ratio R=(sig1-sig2)/(sig1-sig3).
angular_residual(stress_tensor, strikes, ...)	Compute the angle between the direction of the resolved shear stress predicted by the stress tensor and the direction of slip given by the strike/dip/rake data.
aux_plane(s1, d1, r1)	Get Strike and dip of second plane.
check_right_handedness(basis)	Make sure the matrix of column vectors forms a right-handed basis.
compute_traction(stress_tensor, normal)	Compute traction and its normal and shear components on a given plane.
errors_in_data(strike, dip, rake, ...)	This routines was tailored for my applications.
get_CI_levels(azimuths, plunges[, ...])	Computes the 2d histogram in the stereographic space of a collection lines described by their azimuth and plunge.
get_CI_levels_joint(azimuths, plunges[, ...])	Computes the 2d histogram in the stereographic space of a collection lines described by their azimuth and plunge.
get_bearing_plunge(u[, degrees, hemisphere])	The vectors are in the coordinate system (x1, x2, x3): x1: north x2: west x3: upward
hist2d(azimuths, plunges[, nbins, ...])	Computes the 2d histogram in the stereographic space of a collection lines described by their azimuth and plunge.
joint_CDF(count)
kagan_angle(tensor1, tensor2)	Compute the minimum rotation about some axis required to match the two tensors.
mean_angular_residual(stress_tensor, ...)	Mean of the absolute value of the angles returned by angular_residual.
mean_kagan_angle(strikes, dips, rakes[, ...])	Computes the mean kagan angle as a measure of dispersion.
normal_slip_vectors(strike, dip, rake[, ...])	Determine the normal and the slip vectors of the focal mechanism defined by (strike, dip, rake).
p_t_b_axes(normal, slip)	Determine the P (most compressive), T (least compressive) and B (intermediate, or neutral axis) axes from the normal and the slip vectors, following Stein and Wysession 2002, Section 4.5.2.
principal_faults(stress_tensor, ...)	Compute the orientation of the most unstable fault planes given a stress tensor and a coefficient of friction.
quaternion(t, p, b)	Formula of quaternion of rotation matrix with t (least compressive), p (most compressive), b (neutral) components expressed in the (north, east, down) frame of reference.
random_rotation([max_angle])	Generate a random rotation matrix.
reduced_stress_tensor(principal_directions, R)	Computes a normalized stress tensor where the most and least compressive principal stresses are set to -1 and +1, respectively, and the intermediate stress is determined by the shape ratio.
rotation(axis, angle)	Compute the rotation matrix about axis with angle angle.
round_cos(x)	Clip x so that it fits with the [-1,1] interval.
shear_slip_angle_difference(stress_tensor, ...)	Return the angle difference between the slip vector from the focal mechanism solution and the shear traction on the fault determined from the inverted stress tensor.
stress_tensor_eigendecomposition(stress_tensor)	Compute the eigendecomposition of stress tensor.
strike_dip_rake(n, d)	Invert the relationships between strike/dip/rake and normal (n) and slip (d) vectors found in Stein.
strike_dip_rake_to_mt(strike, dip, rake)	Compute the normalized moment tensor described by strike/dip/rake.