def test_pix2sky_sky2pix():
filename = 'tests/test_files/1904-66_SIN.fits'
hdu = fits.open(filename)
im = fi.FitsImage(hdu)
ra, dec = im.pix2sky([0, 0])
x, y = im.sky2pix([ra, dec])
assert_array_almost_equal([0, 0], [x, y])
def test_get_background_rms():
"""Test get_background_rms"""
filename = 'tests/test_files/1904-66_SIN.fits'
hdu = fits.open(filename)
hdu[0].data = np.empty((40, 40))
im = fi.FitsImage(hdu)
if not (im.get_background_rms() > 0): raise AssertionError()
def test_init():
"""Test that FitsImage __init__ works """
filename = 'tests/test_files/1904-66_SIN.fits'
# normal invocation
_ = fi.FitsImage(filename)
# call with an already opened hdu instead of a file name
hdu = fits.open(filename)
_ = fi.FitsImage(hdu)
# set bzero/bscale
hdu[0].header['BZERO'] = 1
hdu[0].header['BSCALE'] = 2
im = fi.FitsImage(hdu)
if not im.bscale == 2: raise AssertionError()
if not im.bzero == 1: raise AssertionError()
# should be able to supply a beam directly
beam = AegeanTools.wcs_helpers.Beam(1, 1, 0)
im = fi.FitsImage(hdu, beam=beam, cube_index=0)
if not (im.beam is beam): raise AssertionError()
# raise exception if the beam cannot be determined
del hdu[0].header['BMAJ']
assert_raises(Exception, fi.FitsImage, hdu)
# test with 3 image dimensions
hdu = fits.open(filename)
hdu[0].data = np.empty((3, 3, 3))
# this should fail
assert_raises(Exception, fi.FitsImage, hdu)
# this should be fine
im = fi.FitsImage(hdu, cube_index=0)
if not (im.x == im.y == 3): raise AssertionError()
# can't work with 4d data
hdu[0].data = np.empty((3, 3, 3, 3))
assert_raises(Exception, fi.FitsImage, hdu)