Exemple #1
0
	def get_physical_size(self):
		''' Calculate the physical size of the box

		Returns:
			box size in comoving Mpc '''
		redsh = hf.nu_to_z(self.get_nu_c())
		cdist = hf.cdist(redsh)
		l = cdist * self.get_fov() * np.pi/180.
		return l
Exemple #2
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	def set_nu_range_cubic(self):
		''' Set the parameters nu_range and dnu so that the
		result of get_noise_cube and get_image_cube have the same
		comoving extent along the frequency axis as along the sides
		The uv grid must be set prior to running this method.
		'''
		#Determine the size of the box
		redsh = hf.nu_to_z(self.get_nu_c())
		cdist = hf.cdist(redsh)
		boxl = cdist*self.get_fov()*np.pi/180.

		#Determine frequency range
		z_lower = hf.cdist_to_z(cdist-boxl/2.)
		z_upper = hf.cdist_to_z(cdist+boxl/2.)
		nu_upper = hf.z_to_nu(z_upper)
		nu_lower = hf.z_to_nu(z_lower)
		self.set_nu_range((nu_lower,nu_upper))

		#Determine frequency step
		if self.get_uv_grid() == None or self.get_uv_grid().shape[0] == 0:
			raise Exception('uv grid must be set before running set_nu_range_cubic')
		gridn = self.get_uv_grid().shape[0]
		self.set_dnu( (nu_lower-nu_upper)/float(gridn) )
Exemple #3
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	def get_z(self):
		''' Get redshift '''
		return hf.nu_to_z(self.get_nu_c())