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- Drude1D

# Drude1D

class astropy.modeling.physical_models.Drude1D(amplitude=1.0, x_0=1.0, fwhm=1.0, **kwargs)

  Bases: `Fittable1DModel`

  Drude model based one the behavior of electons in materials (esp. metals).

  Parameters:
    amplitude `python:float`

      Peak value

    x_0 `python:float`

      Position of the peak

    fwhm `python:float`

      Full width at half maximum

    Model formula:
      \[f(x) = A \frac{(fwhm/x_0)^2}{((x/x_0 - x_0/x)^2 + (fwhm/x_0)^2}\]

  Examples

      import numpy as np
      import matplotlib.pyplot as plt

      from astropy.modeling.models import Drude1D

      fig, ax = plt.subplots()

      # generate the curves and plot them
      x = np.arange(7.5 , 12.5 , 0.1)

      dmodel = Drude1D(amplitude=1.0, fwhm=1.0, x_0=10.0)
      ax.plot(x, dmodel(x))

      ax.set_xlabel('x')
      ax.set_ylabel('F(x)')

      plt.show()

  (png, svg, pdf)

  Attributes Summary

  `amplitude` |
  `fwhm` |
  `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).
  `param_names` | Names of the parameters that describe models of this type.
  `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).
  `x_0` |

  Methods Summary

  `evaluate`(x, amplitude, x_0, fwhm) | One dimensional Drude model function
  `fit_deriv`(x, amplitude, x_0, fwhm) | Drude1D model function derivatives.

  Attributes Documentation

  amplitude = Parameter('amplitude', value=1.0)
  fwhm = Parameter('fwhm', value=1.0)
  input_units
  param_names = ('amplitude', 'x_0', 'fwhm')

    Names of the parameters that describe models of this type.

    The parameters in this tuple are in the same order they should be passed in when initializing a model of a specific type. Some types of models, such as polynomial models, have a different number of parameters depending on some other property of the model, such as the degree.

    When defining a custom model class the value of this attribute is automatically set by the `Parameter` attributes defined in the class body.

  return_units
  x_0 = Parameter('x_0', value=1.0)

  Methods Documentation

  static evaluate(x, amplitude, x_0, fwhm)

    One dimensional Drude model function

  static fit_deriv(x, amplitude, x_0, fwhm)

    Drude1D model function derivatives.