Box1D¶
-
class
astropy.modeling.functional_models.
Box1D
(amplitude=1, x_0=0, width=1, **kwargs)[source]¶ Bases:
astropy.modeling.Fittable1DModel
One dimensional Box model.
- Parameters
amplitude : float
Amplitude A
x_0 : float
Position of the center of the box function
width : float
Width of the box
- Other Parameters
fixed : a dict, optional
A dictionary
{parameter_name: boolean}
of parameters to not be varied during fitting. True means the parameter is held fixed. Alternatively thefixed
property of a parameter may be used.tied : dict, optional
A dictionary
{parameter_name: callable}
of parameters which are linked to some other parameter. The dictionary values are callables providing the linking relationship. Alternatively thetied
property of a parameter may be used.bounds : dict, optional
eqcons : list, optional
A list of functions of length
n
such thateqcons[j](x0,*args) == 0.0
in a successfully optimized problem.ineqcons : list, optional
A list of functions of length
n
such thatieqcons[j](x0,*args) >= 0.0
is a successfully optimized problem.
See also
Notes
Model formula:
\[\begin{split}f(x) = \left \{ \begin{array}{ll} A & : x_0 - w/2 \leq x \leq x_0 + w/2 \\ 0 & : \text{else} \end{array} \right.\end{split}\]Examples
import numpy as np import matplotlib.pyplot as plt from astropy.modeling.models import Box1D plt.figure() s1 = Box1D() r = np.arange(-5, 5, .01) for factor in range(1, 4): s1.amplitude = factor s1.width = factor plt.plot(r, s1(r), color=str(0.25 * factor), lw=2) plt.axis([-5, 5, -1, 4]) plt.show()
Attributes Summary
This property is used to indicate what units or sets of units the evaluate method expects, and returns a dictionary mapping inputs to units (or
None
if any units are accepted).This property is used to indicate what units or sets of units the output of evaluate should be in, and returns a dictionary mapping outputs to units (or
None
if any units are accepted).Methods Summary
evaluate
(x, amplitude, x_0, width)One dimensional Box model function
Attributes Documentation
-
amplitude
= Parameter('amplitude', value=1.0)¶
-
input_units
¶ This property is used to indicate what units or sets of units the evaluate method expects, and returns a dictionary mapping inputs to units (or
None
if any units are accepted).Model sub-classes can also use function annotations in evaluate to indicate valid input units, in which case this property should not be overridden since it will return the input units based on the annotations.
-
param_names
= ('amplitude', 'x_0', 'width')¶
-
return_units
¶ This property is used to indicate what units or sets of units the output of evaluate should be in, and returns a dictionary mapping outputs to units (or
None
if any units are accepted).Model sub-classes can also use function annotations in evaluate to indicate valid output units, in which case this property should not be overridden since it will return the return units based on the annotations.
-
width
= Parameter('width', value=1.0)¶
-
x_0
= Parameter('x_0', value=0.0)¶
Methods Documentation