GroundModel¶

GroundModel class definition.

class GroundModel(thickness, vp, vs, density, identifier=0, misfit=0.0)¶

Bases: object

Class for creating and manipulating GroundModel objects.

Variables:	vp, vs, rh (tk,) – Thickness, compression-wave velocity (Vp), shear-wave velocity (Vs), and mass density defining each layer of the GroundModel, respectively. identifier (int, optional) – Model numeric identifier, default is 0. misfit (float, optional) – Model misfit, default is 0.0.

__init__(thickness, vp, vs, density, identifier=0, misfit=0.0)¶

Initialize a GroundModel object.

Parameters:	thickness (iterable) – Container of float or int denoting layer thickness (one per layer) in meters starting from the ground surface. vp, vs (iterable) – Container of float or int denoting the P- and S-wave velocity of each layer in m/s. density (iterable) – Container of float or int denoting the mass density of each layer in kg/m3. identifier (int, optional) – Model numeric identifier, default is 0. misfit (float, optional) – Model misfit, default is 0.0.
Returns:	GroundModel – Instantiated GroundModel object.
Raises:	`Various` – See :meth: check_input_type <GroundModel.check_input_type and :meth: check_input_value <GroundModel.check_input_value for details.

static calc_pr(vp, vs)¶

Calculate Poisson’s ratio from iterable of vp and vs.

Parameters:	vp, vs (float, int, or iterable) – Vp and Vs values, respectively
Returns:	float or list – Poisson’s ratio, calculated from each vp, vs pair.
Raises:	`ValueError` – If vs>vp or Poisson’s ratio is negative (i.e., vp/vs too close to 1).

check_input(**kwargs)¶: Check input values and types.

static check_input_type(**kwargs)¶

Check inputs are of the appropriate type.

Specifically: 1. Cast GroundModel input to a list of float. 2. Cast meta-information (identifier and misfit to int and float).

Parameters:	**kwargs – Keyword arguments containing name and value pairs.
Raises:	`TypeError` – If values do not pass the aforementioned criteria.

static check_input_value(**kwargs)¶

Check values have appropriate values.

Specifically: 1. Check that all GroundModel parameters are greater than zero. 2. Check that identifier and misfit are greater than zero. 3. Check that vp > vs.

Parameters:	**kwargs – Keyword arguments containing name and value pairs.
Raises:	`ValueError` – If inputs does not pass the aforementioned criteria.

depth¶: Return stair-step version of depth profile.

static depth_to_thick(depths)¶

Convert depths (top of each layer) to thicknesses

Parameters:	depth (list) – List of consecutive depths.
Returns:	list – Thickness for each layer. Half-space is defined with zero thickness.

discretize(dmax, dy=0.5, parameter='vs')¶

Discretize a parameter of the GroundModel.

The GroundModel is discretized in terms of depth from the surface to dmax by dy such that depth will be a list of the form [0:dy:dmax]. When the discretization encounters a parameter boundary the velocity of the upper layer is assigned.

Do not use these discretized models for plotting unless dy is very small, as they may be misleading.

Parameters:	dmax (float) – Maximum depth of discretization. dy (float, optional) – Linear step of discretization in terms of depth, default is 0.5 meter. parameter ({‘vp’, ‘vs’, ‘rh’, ‘pr’}, optional) – Parameter to be discretized, default is ‘vs’.
Returns:	Tuple – Tuple of the form (depth, param) where depth is a list of the discretized depths, and parameter is a list of the discretized parameter at those depths.
Raises:	`KeyError` – If parameter is not one of those options specified.

classmethod from_geopsy(fname)¶

Create from a text file following the Geopsy format.

Parameters:	fname (fname) – File name, may contain a relative or the full path.
Returns:	GroundModel – Initialized GroundModel object.
Raises:	`Various` – If file does not follow the Geopsy format.

classmethod from_simple_profiles(vp_tk, vp, vs_tk, vs, rh_tk, rh)¶

Instantiate GroundModel from simple profiles.

Parameters:	vp_tk, vs_tk, rh_tk (iterable) – Iterable denoting the thicknesses of each parameter, one per layer. vp, vs, rh (iterable) – Iterable denoting the value of Vp, Vs, and mass density respectively.
Returns:	GroundModel – Instantiated GroundModel object.

gm2(parameter)¶

Parameter of GroundModel in stair-step form.

Parameters:	parameter ({‘depth’, ‘vp’, ‘vs’, ‘density’, ‘pr’}) – Desired parameter to transform to stair-step profile.
Returns:	list – Defining the specified parameter.
Raises:	`KeyError` – If parameter is not one of those specified.

nlay¶

pr2¶: Return stair-step version of Poisson’s ratio profile.

rh¶

rh2¶: Return stair-step version of density profile.

simplify(parameter='vs')¶

Remove unnecessary breaks in the parameter specified.

This will typically be used for calculating the median across many profiles.

parameter : {‘vs’,’vp’,’rh’,’density’}, optional: String denoting parameter to be simplified, default is ‘vs’.

Returns:	tuple – Of the form (thickness, parameter) where thickness is a list of simplified thicknesses and parameter is a list of the simplified parameter.

static thick_to_depth(thicknesses)¶

Convert thickness to depth (at top of each layer).

Parameters:	thickness (list) – List of thicknesses defining a ground model.
Returns:	list – List of depths at the top of each layer.

tk¶

txt_repr¶: Text representation of the current GroundModel.

vp2¶: Return stair-step version of Vp profile.

vs2¶: Return stair-step version of Vs profile.

vs30¶

Calculate Vs30 of the GroundModel.

Vs0 is the time-averaged shear-wave velocity in the upper 30m.

Returns:	float – Vs30 of GroundModel.

write_model(fileobj)¶

Write model to open file object following Geopsy format.

Parameters:	fileobj (_io.TextIOWrapper) – Name of file, may be a relative or the full path.
Returns:	None – Writes file to disk.

write_to_mat(fname_prefix)¶

Save GroundModel information to .mat format.

Parameters:	fname_prefix (str) – Name of file (excluding the .mat extension) where the file should be saved, may be a relative or the full path.
Returns:	None – Writes file to disk.

write_to_txt(fname)¶

Write GroundModel to file that follows the Geospy format.

Parameters:	fname (str) – Name of file, may contain a relative or the full path.
Returns:	None – Writes file to disk.