spec_analysis.simulate

The simulate module provides functions for simulating spectra (wavlength and lfux arrays) with absorption features according to various toy models. This is useful when testing or visualizing the behavior of an analysis procedure.

Usage Examples:

We here demonstrate the simulation of an absoprion feature with a gaussian profile. For a list of available profiles, see the API Documentation.

 1
 2
 3
 4
 5
 6
 7
 8
 9
10
11
12
13
14
15
import numpy as np
from matplotlib import pyplot as plt
from spec_analysis.simulate import gaussian

# Simulate a gaussian with a peak at 1200 wavelength units
wave = np.arange(1000, 2000)
flux, flux_err = gaussian(wave, stddev=100)

# Visualize the result
plt.errorbar(wave, flux, yerr=flux_err, linestyle='', alpha=.5, label='Error')
plt.plot(wave, flux, color='k', label='Flux')
plt.xlabel('Wavelength')
plt.ylabel('Flux')
plt.legend()
plt.show()

API Documentation

spec_analysis.simulate.delta_func(wave, m=0, b=0, peak_wave=(), amplitude=1, seed=None)[source]

Simulate linear flux with interspersed delta functions and normal errors

Parameters:
  • wave (ndarray) – Array of wavelengths to simulate flux for
  • m (float) – Slope of the continuum
  • b (float) – Y-intercept of the continuum
  • peak_wave (tuple) – Wavelengths of the delta functions
  • amplitude (float) – Height of the delta functions
  • seed (float) – Optional seed for random number generator
Returns:

  • An array of flux values
  • An array of error values
spec_analysis.simulate.gaussian(wave, amplitude=-1, mean=None, stddev=1, offset=100, seed=0)[source]

Simulate gaussian flux with normal errors

Parameters:
  • wave (ndarray) – Array of wavelengths to simulate flux for
  • amplitude (float) – Amplitude of the Gaussian
  • mean (float) – Average of the Gaussian (default: mean of wave)
  • stddev (float) – Standard deviation of the Gaussian
  • offset (float) – Vertical offset of the Gaussian
  • seed (float) – Seed for random number generator
Returns:

  • An array of flux values
  • An array of error values
spec_analysis.simulate.tophat(wave, m=0, b=1, start=100, end=-100, height=0, seed=0)[source]

Simulate a top-hat absorption feature with normal errors

Setting height=None will simulate just the continuum

Parameters:
  • wave (ndarray) – Array of wavelengths to simulate flux for
  • m (float) – Slope of the continuum (default: 0)
  • b (float) – Y-intercept of the continuum (default: 1)
  • start (int) – Starting index for the top-hat (default: 100)
  • end (int) – Ending index for the top-hat (default: -100)
  • height (float) – Height of the top-hat (default: 0)
  • seed (float) – Seed for random number generator (default: 0)
Returns:

  • An array of flux values
  • An array of error values