shakelib.gmpe.nullgmpe

A GMPE that returns a constant everywhere. Useful for testing, but nothing else.

class shakelib.gmpe.nullgmpe.NullGMPE(mean=0, phi=0.8, tau=0.6)[source]

Bases: GMPE

This is a GMPE for testing. It returns the mean and stddevs specified in the constructor.

The default constructor takes three named arguments:

Parameters:

  • mean (float) – the mean value returned by the GMPE (default=0). This value is returned for all locations, regardles of the IMT or the contents of sites, rupture and distance contexts.

  • phi (float) – the within-event standard deviation returned by the GMPE (default=0.8)

  • tau (float) – the between-event standard deviation returned by the GMPE (default=0.6)

The total standard deviation returned will be sqrt(phi^2 + tau^2).

DEFINED_FOR_TECTONIC_REGION_TYPE = 'Active Shallow Crust'

Reference to a tectonic region type this GSIM is defined for. One GSIM can implement only one tectonic region type.

DEFINED_FOR_INTENSITY_MEASURE_TYPES = frozenset({<function SA>, <function PGA>, <function PGV>})

Set of intensity measure types this GSIM can calculate. A set should contain classes from module openquake.hazardlib.imt.

DEFINED_FOR_INTENSITY_MEASURE_COMPONENT = 'Greater of two horizontal'

intensity measure component type <openquake.hazardlib.const.IMC> this GSIM can calculate mean and standard deviation for.

Type:

Reference to a

Type:

class

DEFINED_FOR_STANDARD_DEVIATION_TYPES = frozenset({'Inter event', 'Intra event', 'Total'})

Set of standard deviation types this GSIM can calculate.

REQUIRES_SITES_PARAMETERS = frozenset({'vs30'})

Set of site parameters names this GSIM needs. The set should include strings that match names of the attributes of a site object. Those attributes are then available in the SitesContext object with the same names.

REQUIRES_RUPTURE_PARAMETERS = frozenset({})

Set of rupture parameters (excluding distance information) required by GSIM. Supported parameters are:

mag

Magnitude of the rupture.

dip

Rupture’s surface dip angle in decimal degrees.

rake

Angle describing the slip propagation on the rupture surface, in decimal degrees. See nodalplane for more detailed description of dip and rake.

ztor

Depth of rupture’s top edge in km. See get_top_edge_depth().

These parameters are available from the RuptureContext object attributes with same names.

REQUIRES_DISTANCES = frozenset({'rjb'})

Set of types of distance measures between rupture and sites. Possible values are:

rrup

Closest distance to rupture surface. See get_min_distance().

rjb

Distance to rupture’s surface projection. See get_joyner_boore_distance().

rx

Perpendicular distance to rupture top edge projection. See get_rx_distance().

ry0

Horizontal distance off the end of the rupture measured parallel to strike. See get_ry0_distance().

rcdpp

Direct point parameter for directivity effect centered on the site- and earthquake-specific average DPP used. See get_dppvalue().

rvolc

Source to site distance passing through surface projection of volcanic zone.

All the distances are available from the DistancesContext object attributes with same names. Values are in kilometers.

get_mean_and_stddevs(sites, rup, dists, imt, stddev_types)[source]

Implements the OpenQuake GroundShakingIntensityModel get_mean_and_stddevs interface. See superclass method.

Returns a constant values for all locations specified in the dists.rbj array, regardless of the contents of that array or any of the other contexts. The imt is also ignored.

COEFFS = <CoeffsTable c1>