landlab.components.network_sediment_transporter.sediment_pulser_at_links¶

class SedimentPulserAtLinks[source]¶

Bases: SedimentPulserBase

Send a pulse of parcels to specific links in a channel network

SedimentPulserAtLinks is instantiated by specifying the NetworkModelGrid it will pulse the parcels into and the time(s) when a pulse is allowed to occur. It inherits attributes and functions from the SedimentPulserBase.

SedimentPulserAtLinks is run (adds parcels to DataRecord) by calling the instance with a list of links and a list of the number of parcels added to each link.

If parcel attributes are constant with time and uniform across the basin, these constant-uniform-attributes can be defined when SedimentPulserAtLinks is instantiated. If parcel attributes vary with location and time, the user specifies the varying parcel attributes each time the instance is called with a list for each attribute of length equal to the number of links included in the pulse.

Code author: Jeff Keck, Allison Pfeiffer, Shelby Ahrendt (with help from Eric Hutton and Katy Barnhart)

Examples

>>> import numpy as np
>>> from landlab import NetworkModelGrid

Create the network model grid the parcels will be added to.

>>> y_of_node = (0, 100, 200, 200, 300, 400, 400, 125)
>>> x_of_node = (0, 0, 100, -50, -100, 50, -150, -100)
>>> nodes_at_link = ((1, 0), (2, 1), (1, 7), (3, 1), (3, 4), (4, 5), (4, 6))
>>> grid = NetworkModelGrid((y_of_node, x_of_node), nodes_at_link)
>>> grid.at_link["channel_width"] = np.full(grid.number_of_links, 1.0)  # m
>>> grid.at_link["channel_slope"] = np.full(grid.number_of_links, 0.01)  # m / m
>>> grid.at_link["reach_length"] = np.full(grid.number_of_links, 100.0)  # m

Define a function that contains which times a pulse is allowed to occur. This function says a pulse can occur at any time

>>> def time_to_pulse(time):
...     return True
...

Instantiate SedimentPulserAtLinks

>>> make_pulse = SedimentPulserAtLinks(grid, time_to_pulse=time_to_pulse)

Run the instance with inputs for the time, link location and number of parcels. Other attributes will use the default values in the base class

>>> time = 11
>>> links = [2, 6]
>>> n_parcels_at_link = [2, 3]
>>> parcels = make_pulse(
...     time=time, links=links, n_parcels_at_link=n_parcels_at_link
... )

Check the element_id of each parcel

>>> print(parcels.dataset["element_id"].values)
[[2]
 [2]
 [6]
 [6]
 [6]]

Create SedimentPulserAtLinks.

Parameters:

grid (ModelGrid) – landlab ModelGrid to place sediment parcels on.
time_to_pulse (function, optional) – The condition when a pulse occurs using the _pulse_characteristics method. If not specified, a pulse occurs whenever the instance is run
parcels (landlab DataRecord) – Tracks parcel location and variables.
D50 (float, optional) – Median grain size [m].
D84_D50 (float, optional) – Ratio of 84th percentile grain size to the median grain size.
rho_sediment (float, optional) – Sediment grain density [kg / m^3].
parcel_volume (float) – Parcel volume [m^3]
abrasion_rate (float) – Volumetric abrasion exponent [1 / m]

__call__(time, links=None, n_parcels_at_link=None, D50=None, D84_D50=None, rho_sediment=None, parcel_volume=None, abrasion_rate=None)[source]¶

specify the time, link(s) and attributes of pulses added to a NetworkModelGrid at stochastically determined locations within the link(s).

Parameters:

time (integer or datetime64) – Time that the pulse is occurs.
links (list of int) – Link ID # that parcels are added to.
n_parcels_at_link (list of int) – Number of parcels added to each link listed in links
D50 (list of float, optional) – Median grain size of parcels added to each link listed in links [m].
D84_D50 (list of float, optional) – Ratio of 84th percentile grain size to the median grain size.
rho_sediment (list of float, optional) – Density of grains [kg / m^3].
parcel_volume (list of float, optional) – Volume of each parcel added to link listed in links [m^3].
abrasion_rate (list of float, optional) – Rate that grain size decreases with distance along channel [mm / km?].

Returns:

DataRecord containing all information on each individual parcel.

Return type:

parcels

__init__(grid, time_to_pulse=None, parcels=None, D50=0.05, D84_D50=2.1, rho_sediment=2650.0, parcel_volume=0.5, abrasion_rate=0.0, rng=None)[source]¶

Create SedimentPulserAtLinks.

Parameters:

grid (ModelGrid) – landlab ModelGrid to place sediment parcels on.
time_to_pulse (function, optional) – The condition when a pulse occurs using the _pulse_characteristics method. If not specified, a pulse occurs whenever the instance is run
parcels (landlab DataRecord) – Tracks parcel location and variables.
D50 (float, optional) – Median grain size [m].
D84_D50 (float, optional) – Ratio of 84th percentile grain size to the median grain size.
rho_sediment (float, optional) – Sediment grain density [kg / m^3].
parcel_volume (float) – Parcel volume [m^3]
abrasion_rate (float) – Volumetric abrasion exponent [1 / m]

static __new__(cls, *args, **kwds)¶

cite_as = ''¶

property coords¶: Return the coordinates of nodes on grid attached to the component.

property current_time¶

Current time.

Some components may keep track of the current time. In this case, the current_time attribute is incremented. Otherwise it is set to None.

Return type:: current_time

definitions = ()¶

classmethod from_path(grid, path)¶

Create a component from an input file.

Parameters:

grid (ModelGrid) – A landlab grid.
path (str or file_like) – Path to a parameter file, contents of a parameter file, or a file-like object.

Returns:

A newly-created component.

Return type:

Component

property grid¶: Return the grid attached to the component.

initialize_optional_output_fields()¶

Create fields for a component based on its optional field outputs, if declared in _optional_var_names.

This method will create new fields (without overwrite) for any fields output by the component as optional. New fields are initialized to zero. New fields are created as arrays of floats, unless the component also contains the specifying property _var_type.

initialize_output_fields(values_per_element=None)¶

Create fields for a component based on its input and output var names.

This method will create new fields (without overwrite) for any fields output by, but not supplied to, the component. New fields are initialized to zero. Ignores optional fields. New fields are created as arrays of floats, unless the component specifies the variable type.

Parameters:: values_per_element (int (optional)) – On occasion, it is necessary to create a field that is of size (n_grid_elements, values_per_element) instead of the default size (n_grid_elements,). Use this keyword argument to acomplish this task.

input_var_names = ()¶

name = 'SedimentPulserAtLinks'¶

optional_var_names = ()¶

output_var_names = ()¶

property shape¶: Return the grid shape attached to the component, if defined.

unit_agnostic = False¶

units = ()¶

classmethod var_definition(name)¶

Get a description of a particular field.

Parameters:: name (str) – A field name.
Returns:: A description of each field.
Return type:: tuple of (name, *description*)

classmethod var_help(name)¶

Print a help message for a particular field.

Parameters:: name (str) – A field name.

classmethod var_loc(name)¶

Location where a particular variable is defined.

Parameters:: name (str) – A field name.
Returns:: The location (‘node’, ‘link’, etc.) where a variable is defined.
Return type:: str

var_mapping = ()¶

classmethod var_type(name)¶

Returns the dtype of a field (float, int, bool, str…).

Parameters:: name (str) – A field name.
Returns:: The dtype of the field.
Return type:: dtype

classmethod var_units(name)¶

Get the units of a particular field.

Parameters:: name (str) – A field name.
Returns:: Units for the given field.
Return type:: str