# create_model_component¶

sherpa.astro.ui.create_model_component(typename=None, name=None)

Create a model component.

Model components created by this function are set to their default values. Components can also be created directly using the syntax typename.name, such as in calls to set_model and set_source (unless you have called set_model_autoassign_func to change the default model auto-assignment setting).

Parameters: typename (str) – The name of the model. This should match an entry from the return value of list_models, and defines the type of model. name (str) – The name used to refer to this instance, or component, of the model. A Python variable will be created with this name that can be used to inspect and change the model parameters, as well as use it in model expressions. model the sherpa.models.Model object created

delete_model_component()
Delete a model component.
get_model_component()
Returns a model component given its name.
list_models()
List the available model types.
list_model_components()
List the names of all the model components.
set_model()
Set the source model expression for a data set.
set_model_autoassign_func()
Set the method used to create model component identifiers.

Notes

This function can over-write an existing component. If the over-written component is part of a source expression - as set by set_model - then the model evaluation will still use the old model definition (and be able to change the fit parameters), but direct access to its parameters is not possible since the name now refers to the new component (this is true using direct access, such as mname.parname, or with set_par).

Examples

Create an instance of the powlaw1d model called pl, and then freeze its gamma parameter to 2.6.

>>> create_model_component("powlaw1d", "pl")
>>> pl.gamma = 2.6
>>> freeze(pl.gamma)


Create a blackbody model called bb, check that it is reconized as a component, and display its parameters:

>>> create_model_component("bbody", "bb")
>>> list_model_components()
>>> print(bb)
>>> print(bb.ampl)