Sine1D¶
- class astropy.modeling.functional_models.Sine1D(*args, meta=None, name=None, **kwargs)[source]¶
Bases:
_Trigonometric1D
One dimensional Sine model.
- Parameters:
- amplitude
python:float
Oscillation amplitude
- frequency
python:float
Oscillation frequency
- phase
python:float
Oscillation phase
- amplitude
- Other Parameters:
- fixed
a
python: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
python: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
python:dict
, optional A dictionary
{parameter_name: value}
of lower and upper bounds of parameters. Keys are parameter names. Values are a list or a tuple of length 2 giving the desired range for the parameter. Alternatively, themin
andmax
properties of a parameter may be used.- eqcons
python:list
, optional A list of functions of length
n
such thateqcons[j](x0,*args) == 0.0
in a successfully optimized problem.- ineqcons
python:list
, optional A list of functions of length
n
such thatieqcons[j](x0,*args) >= 0.0
is a successfully optimized problem.
- fixed
Notes
Model formula:
\[f(x) = A \sin(2 \pi f x + 2 \pi p)\]Examples
import numpy as np import matplotlib.pyplot as plt from astropy.modeling.models import Sine1D plt.figure() s1 = Sine1D(amplitude=1, frequency=.25) r=np.arange(0, 10, .01) for amplitude in range(1,4): s1.amplitude = amplitude plt.plot(r, s1(r), color=str(0.25 * amplitude), lw=2) plt.axis([0, 10, -5, 5]) plt.show()
Methods Summary
evaluate
(x, amplitude, frequency, phase)One dimensional Sine model function
fit_deriv
(x, amplitude, frequency, phase)One dimensional Sine model derivative
Methods Documentation