Parameters

class gammapy.modeling.Parameters(parameters=None)

Bases: collections.abc.Sequence

Parameters container.

• List of Parameter objects.

• Covariance matrix.

Parameters

parameterslist of Parameter

List of parameters

Attributes Summary

free_parameters	List of free parameters
max	Parameter maxima (numpy.ndarray).
min	Parameter mins (numpy.ndarray).
names	List of parameter names
types	Parameter types
unique_parameters	Unique parameters (Parameters).
value	Parameter values (numpy.ndarray).

Methods Summary

autoscale()	Autoscale all parameters.
check_limits()	Check parameter limits and emit a warning
copy()	A deep copy
count(value)
freeze_all()	Freeze all parameters
from_dict(data)
from_stack(parameters_list)	Create Parameters by stacking a list of other Parameters objects.
index(val)	Get position index for a given parameter.
restore_status([restore_values])	Context manager to restore status.
select([name, type, frozen])	Create a mask of models, true if all conditions are verified
set_parameter_factors(factors)	Set factor of all parameters.
to_dict()
to_table()	Convert parameter attributes to Table.
unfreeze_all()	Unfreeze all parameters (even those frozen by default)

Attributes Documentation

free_parameters

List of free parameters

max

Parameter maxima (numpy.ndarray).

min

Parameter mins (numpy.ndarray).

names

List of parameter names

types

Parameter types

unique_parameters

Unique parameters (Parameters).

value

Parameter values (numpy.ndarray).

Methods Documentation

autoscale()

Autoscale all parameters.

See autoscale()

check_limits()

Check parameter limits and emit a warning

copy()

A deep copy

count(value) → integer -- return number of occurrences of value

freeze_all()

Freeze all parameters

classmethod from_dict(data)

classmethod from_stack(parameters_list)

Create Parameters by stacking a list of other Parameters objects.

Parameters

parameters_listlist of Parameters

List of Parameters objects

index(val)

Get position index for a given parameter.

The input can be a parameter object, parameter name (str) or if a parameter index (int) is passed in, it is simply returned.

restore_status(restore_values=True)

Context manager to restore status.

A copy of the values is made on enter, and those values are restored on exit.

Parameters

restore_valuesbool

Restore values if True, otherwise restore only frozen status.

Examples

from gammapy.modeling.models import PowerLawSpectralModel
pwl = PowerLawSpectralModel(index=2)
with pwl.parameters.restore_status():
    pwl.parameters["index"].value = 3
print(pwl.parameters["index"].value)

select(name=None, type=None, frozen=None)

Create a mask of models, true if all conditions are verified

Parameters

namestr or list

Name of the parameter

type{None, spatial, spectral, temporal}

type of models

frozenbool

Select frozen parameters if True, exclude them if False.

Returns

parametersParameters

Selected parameters

set_parameter_factors(factors)

Set factor of all parameters.

Used in the optimizer interface.

to_dict()

to_table()

Convert parameter attributes to Table.

unfreeze_all()

Unfreeze all parameters (even those frozen by default)