Basic Usage

pyGnuastro is divided into separate modules(Overview of the Python Modules) and each module can be imported using the '.' after the package name as:: import pygnuastro.MODULE_NAME.

For Example

import pygnuastro.cosmology
# Calling the age function in the cosmology module
print(pygnuastro.cosomology.age(5))

Most functions also provide passing arguments as keywords.

import pygnuastro.cosmology as cosmo
proper_distance = cosmo.proper_distance(H0 = 65, Z = 5,
                                        omatter = 0.3,
                                        olambda = 0.2,
                                        oradiation = 0.5)

For functions which are supposed to return or pass a NumPy array, we take an example of a simple program which reads an input FITS image and stores it as a NumPy array, then

import pygnuastro.fits
import numpy
# Here 'in' will be a NumPy array.
in = pygnuastro.fits.img_read(filename = "input.fits", hdu = 0)
if gnuastro.fits.img_write(in, "output.fits"):
  print("Write successful.")
else:
  print("Error in writing file")