fpsim.parameters module

Handle sim parameters

class Pars(pars=None, *args, **kwargs)

Bases: dict

Class to hold a dictionary of parameters, and associated methods.

Usually not called by the user directly – use fp.pars() instead.

Parameters

pars (dict) – dictionary of parameters

copy()

Shortcut for deep copying

to_dict()

Return parameters as a new dictionary

to_json(filename, **kwargs)

Export parameters to a JSON file.

Parameters

• filename (str) – filename to save to

• kwargs (dict) – passed to sc.savejson

Example::

sim.pars.to_json(‘my_pars.json’)

from_json(filename, **kwargs)

Import parameters from a JSON file.

Parameters

• filename (str) – filename to load from

• kwargs (dict) – passed to sc.loadjson

Example::

sim.pars.from_json(‘my_pars.json’)

validate(die=True, update=True)

Perform validation on the parameters

Parameters

• die (bool) – whether to raise an exception if an error is encountered

• update (bool) – whether to update the method and age maps

update_method_eff(method, eff=None, verbose=False)

Update efficacy of one or more contraceptive methods.

Parameters

• method (str/dict) – method to update, or dict of method:value pairs

• eff (float) – new value of contraceptive efficacy (not required if method is a dict)

Examples::

pars.update_method_eff(‘Injectables’, 0.99) pars.update_method_eff({‘Injectables’:0.99, ‘Condoms’:0.50})

update_method_prob(source=None, dest=None, factor=None, value=None, ages=None, matrix=None, copy_from=None, verbose=False)

Updates the probability matrices with a new value. Usually used via the intervention fp.update_methods().

Parameters

• source (str/int) – the method to switch from

• dest (str/int) – the method to switch to

• factor (float) – if supplied, multiply the probability by this factor

• value (float) – if supplied, change the probability to this value

• ages (str/list) – the ages to modify (default: all)

• matrix (str) – which switching matrix to modify (default: annual)

• copy_from (str) – the existing method to copy the probability vectors from (optional)

• verbose (bool) – how much detail to print

reset_methods_map()

Refresh the methods map to be self-consistent

add_method(name, eff, modern=True)

Add a new contraceptive method to the switching matrices.

A new method should only be added before the sim is run, not during.

Note: the matrices are stored in pars['methods']['raw']; this method is a helper function for modifying those. For more flexibility, modify them directly. The fp.update_methods() intervention can be used to modify the switching probabilities later.

Parameters

• name (str) – the name of the new method

• eff (float) – the efficacy of the new method

• modern (bool) – whether it’s a modern method (default: yes)

Examples::

pars = fp.pars() pars.add_method(‘New method’, 0.90) pars.add_method(name=’Male pill’, eff=0.98, modern=True)

rm_method(name)

Removes a contraceptive method from the switching matrices.

A method should only be removed before the sim is run, not during, since the method associated with each person in the sim will point to the wrong index.

Parameters

name (str/ind) – the name or index of the method to remove

Example::

pars = fp.pars() pars.rm_method(‘Other modern’)

reorder_methods(order)

Reorder the contraceptive method matrices.

Method reordering should be done before the sim is created (or at least before it’s run).

Parameters

• order (arr) – the new order of methods, either ints or strings

• sim (Sim) – if supplied, also reorder

Exampls::

pars = fp.pars() pars.reorder_methods([2, 6, 4, 7, 0, 8, 5, 1, 3])

pars(location=None, validate=True, die=True, update=True, **kwargs)

Function for getting default parameters.

Parameters

• location (str) – the location to use for the parameters; use ‘test’ for a simple test set of parameters

• validate (bool) – whether to perform validation on the parameters

• die (bool) – whether to raise an exception if validation fails

• update (bool) – whether to update values during validation

• kwargs (dict) – custom parameter values

Example::

pars = fp.pars(location=’senegal’)