MeasureIABase

measureia.MeasureIABase

Bases: SimInfo

Base class for MeasureIA package that includes some general methods used throughout the package.

Attributes:
  • Num_position (int) –

    Number of objects in the position sample. This value is updated in jackknife realisations.

  • Num_shape (int) –

    Number of objects in the shape sample. This value is updated in jackknife realisations.

  • r_min (float) –

    Minimum bound of (projected) separation length; bin edge. Default is 0.1.

  • r_max (float) –

    Maximum bound of (projected) separation length; bin edge. Default is 20.

  • r_bins (ndarray) –

    Bin edges of the (projected) separation length (r_p or r).

  • pi_bins (ndarray) –

    Bin edges of the line of sight (pi).

  • mu_r_bins (ndarray) –

    Bin edges of the mu_r.

Methods:

Name Description
calculate_dot_product_arrays

Calculates dot product of elements of two arrays

get_ellipticity

Given e and phi, e_+ and e_x components of ellipticity are returned.

get_random_pairs

Analytical RR for a (rp,pi) bin.

get_volume_spherical_cap

Volume of an (r,mu_r) bin.

get_random_pairs_r_mur

Analytical RR for a (r,mu_r) bin.

_measure_w_g_i

Measure wgg or wg+ from xi grid provided by MeasureWBox or MeasureWLightcone class methods.

_measure_multipoles

Measure multipoles (gg or g+) from xi grid provided by MeasureMultipolesBox or MeasureMultipolesLightcone class methods.

_obs_estimator

Combines elements (DD, RR, etc) of xi estimators into xi_gg or xi_g+ for MeasureIALightcone.

assign_jackknife_patches

Given positions of multiple samples, defines jackknife patches and returns index of every object in the sample.

Notes

Inherits attributes from 'SimInfo', where 'boxsize', 'L_0p5' and 'snap_group' are used in this class.

Source code in src/measureia/measure_IA_base.py
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class MeasureIABase(SimInfo):
	"""Base class for MeasureIA package that includes some general methods used throughout the package.

	Attributes
	----------
	Num_position : int
		Number of objects in the position sample. This value is updated in jackknife realisations.
	Num_shape : int
		Number of objects in the shape sample. This value is updated in jackknife realisations.
	r_min : float
		Minimum bound of (projected) separation length; bin edge. Default is 0.1.
	r_max : float
		Maximum bound of (projected) separation length; bin edge. Default is 20.
	r_bins : ndarray
		Bin edges of the (projected) separation length (r_p or r).
	pi_bins : ndarray
		Bin edges of the line of sight (pi).
	mu_r_bins : ndarray
		Bin edges of the mu_r.

	Methods
	-------
	calculate_dot_product_arrays()
		Calculates dot product of elements of two arrays
	get_ellipticity()
		Given e and phi, e_+ and e_x components of ellipticity are returned.
	get_random_pairs()
		Analytical RR for a (rp,pi) bin.
	get_volume_spherical_cap()
		Volume of an (r,mu_r) bin.
	get_random_pairs_r_mur()
		Analytical RR for a (r,mu_r) bin.
	_measure_w_g_i()
		Measure wgg or wg+ from xi grid provided by MeasureWBox or MeasureWLightcone class methods.
	_measure_multipoles()
		Measure multipoles (gg or g+) from xi grid provided by MeasureMultipolesBox or MeasureMultipolesLightcone
		class methods.
	_obs_estimator()
		Combines elements (DD, RR, etc) of xi estimators into xi_gg or xi_g+ for MeasureIALightcone.
	assign_jackknife_patches()
		Given positions of multiple samples, defines jackknife patches and returns index of every object in the sample.

	Notes
	-----
	Inherits attributes from 'SimInfo', where 'boxsize', 'L_0p5' and 'snap_group' are used in this class.

	"""

	def __init__(
			self,
			data,
			output_file_name,
			simulation=None,
			snapshot=None,
			separation_limits=[0.1, 20.0],
			num_bins_r=8,
			num_bins_pi=20,
			pi_max=None,
			boxsize=None,
			periodicity=True,
	):
		"""
		The __init__ method of the MeasureIABase class.

		Parameters
		----------
		data : dict or NoneType
			Dictionary with data needed for calculations.
			For cartesian coordinates, the keywords are:
			'Position' and 'Position_shape_sample': (N_p,3), (N_s,3) ndarrays with the x, y, z coordinates
			of the N_p, N_s objects in the position and shape samples, respectively.
			'Axis_Direction': (N_s,2) ndarray with the two elements of the unit vectors describing the
			axis direction of the projected axis of the object shape.
			'LOS': index referring back to the column number in the 'Position' samples that contains the
			line-of-sight coordinate. (e.g. if the shapes are projected over the z-axis, LOS=2)
			'q': (N_s) array containing the axis ratio q=b/a for each object in the shape sample.
			For lightcone coordinates, the keywords are:
			'Redshift' and 'Redshift_shape_sample': (N_p) and (N_s) ndarray with redshifts of position and shape samples.
			'RA' and 'RA_shape_sample': (N_p) and (N_s) ndarray with RA coordinate of position and shape samples.
			'DEC' and 'DEC_shape_sample': (N_p) and (N_s) ndarray with DEC coordinate of position and shape samples.
			'e1' and 'e2': (N_s) arrays with the two ellipticity components e1 and e2 of the shape sample objects.
		output_file_name : str
			Name and filepath of the file where the output should be stored. Needs to be hdf5-type.
		simulation : str or NoneType, optional
			Indicator of simulation, obtaining correct boxsize in cMpc/h automatically. 
			Choose from [TNG100, TNG100_2, TNG300, EAGLE, HorizonAGN, FLAMINGO_L1, FLAMINGO_L2p8, COLIBRE_L400,
			COLIBRE_L200].
			Default is None, in which case boxsize needs to be added manually; or in the case of observational data, 
			the pi_max.
		snapshot : int or str or NoneType, optional
			Number of the snapshot, which, if given, will ensure that the output file to contains a group
			'Snapshot_[snapshot]'. If None, the group is omitted from the output file structure. Default is None.
		separation_limits : iterable of 2 entries, optional
			Bounds of the (projected) separation vector length bins in cMpc/h (so, r or r_p). Default is [0.1,20].
		num_bins_r : int, optional
			Number of bins for (projected) separation vector. Default is 8.
		num_bins_pi : int, optional
			Number of bins for line of sight (LOS) vector, pi or mu_r when multipoles are measured. Default is 20.
		pi_max : int or float, optional
			Bound for line of sight bins. Bounds will be [-pi_max, pi_max]. Default is None, in which case half the
			boxsize will be used.
		boxsize : int or float or NoneType, optional
			If simulation is not included in SimInfo, a manual boxsize can be added here. Make sure simulation=None
			and the boxsize units are equal to those in the data dictionary. Default is None.
		periodicity : bool, optional
			If True, the periodic boundary conditions of the simulation box are taken into account. If False, they are
			ignored. Note that because this code used analytical randoms for the simulations, the correlations will not
			be correct in this case and only DD and S+D terms should be studied. Non-periodic randoms can be measured by
			providing random data to the code and considering the DD term that is measured. Correlations and covariance
			matrix will need to be reconstructed from parts. [Please add a request for teh integration of this method of
			this if you would like to use this option often.] Default is True.

		"""
		SimInfo.__init__(self, simulation, snapshot, boxsize)
		# --- validate numeric configuration parameters ---
		if not (isinstance(num_bins_r, (int, np.integer)) and not isinstance(num_bins_r, bool) and num_bins_r >= 1):
			raise ValueError(f"num_bins_r must be an integer >= 1, got {num_bins_r!r}.")
		if not (isinstance(num_bins_pi, (int, np.integer)) and not isinstance(num_bins_pi, bool) and num_bins_pi >= 1):
			raise ValueError(f"num_bins_pi must be an integer >= 1, got {num_bins_pi!r}.")
		try:
			r_min_check, r_max_check = separation_limits
		except (TypeError, ValueError):
			raise ValueError(
				f"separation_limits must be a length-2 sequence [r_min, r_max], got {separation_limits!r}.")
		if not (0 < r_min_check < r_max_check):
			raise ValueError(
				f"separation_limits must satisfy 0 < r_min < r_max, got {separation_limits}.")
		if self.boxsize is not None and self.boxsize is not False and not (self.boxsize > 0):
			raise ValueError(f"boxsize must be > 0, got {self.boxsize!r}.")
		if pi_max is not None and not (pi_max > 0):
			raise ValueError(f"pi_max must be > 0, got {pi_max!r}.")
		self.data = data
		self.output_file_name = output_file_name
		self.periodicity = periodicity
		if periodicity:
			periodic = "periodic "
		else:
			periodic = ""
		try:
			self.Num_position = len(data["Position"])  # number of halos in position sample
			self.Num_shape = len(data["Position_shape_sample"])  # number of halos in shape sample
		except (KeyError, TypeError):  # TypeError: data is None
			try:
				self.Num_position = len(data["RA"])
				self.Num_shape = len(data["RA_shape_sample"])
			except (KeyError, TypeError):
				self.Num_position = 0
				self.Num_shape = 0
				print("Warning: no Position or Position_shape_sample given.")
		if self.Num_position > 0:
			if "weight" not in self.data:
				self.data["weight"] = np.ones(self.Num_position)
			if "weight_shape_sample" not in self.data:
				self.data["weight_shape_sample"] = np.ones(self.Num_shape)
		self.r_min = separation_limits[0]  # cMpc/h
		self.r_max = separation_limits[1]  # cMpc/h
		self.num_bins_r = num_bins_r
		self.num_bins_pi = num_bins_pi
		self.r_bins = np.logspace(np.log10(self.r_min), np.log10(self.r_max), self.num_bins_r + 1)
		if pi_max == None:
			if self.L_0p5 is None:
				raise ValueError(
					"Both pi_max and boxsize are None. Provide input on one of them to determine the integration limit pi_max.")
			else:
				pi_max = self.L_0p5
		self.pi_bins = np.linspace(-pi_max, pi_max, self.num_bins_pi + 1)
		self.mu_r_bins = np.linspace(-1, 1, self.num_bins_pi + 1)
		if simulation == False:
			print(f"MeasureIA object initialised with:\n \
					observational data.\n \
					There are {self.Num_shape} galaxies in the shape sample and {self.Num_position} galaxies in the position sample.\n\
					The separation bin edges are given by {self.r_bins} Mpc.\n \
					There are {num_bins_r} r or r_p bins and {num_bins_pi} pi bins.\n \
					The maximum pi used for binning is {pi_max}.\n \
					The data will be written to {self.output_file_name}")
		else:
			print(f"MeasureIA object initialised with:\n \
			simulation {simulation} that has a {periodic}boxsize of {self.boxsize} cMpc/h.\n \
			There are {self.Num_shape} galaxies in the shape sample and {self.Num_position} galaxies in the position sample.\n\
			The separation bin edges are given by {self.r_bins} cMpc/h.\n \
			There are {num_bins_r} r or r_p bins and {num_bins_pi} pi bins.\n \
			The maximum pi used for binning is {pi_max}.\n \
			The data will be written to {self.output_file_name}")
		return

	@staticmethod
	def calculate_dot_product_arrays(a1, a2):
		"""Calculates the dot product over 2 2D arrays across axis 1 so that dot_product[i] = np.dot(a1[i],a2[i])

		Parameters
		----------
		a1 : ndarray
			First array
		a2 : ndarray
			Second array

		Returns
		-------
		ndarray
			Dot product of columns of arrays

		"""
		dot_product = np.zeros(np.shape(a1)[0])
		for i in np.arange(0, np.shape(a1)[1]):
			dot_product += a1[:, i] * a2[:, i]
		return dot_product

	@staticmethod
	def get_ellipticity(e, phi):
		"""Calculates the radial (+) and cross (x) components of the ellipticity with respect to the
		separation vector, following the intrinsic-alignment sign convention: e_+ > 0 means the
		major axis points along the separation vector (radial alignment), so radial alignment
		gives w_g+ > 0.

		For 2D input, e1 and e2 must follow the standard survey shear-catalogue convention
		(components defined on the local (RA, DEC) axes as delivered by e.g. lensfit/metacal-style
		catalogues and expected by TreeCorr). Note that the IA e_+ has the opposite sign to the
		lensing tangential shear: e_+ = -gamma_t.

		Parameters
		----------
		e : ndarray
			if 1D: size of the ellipticity vector; if 2D: e1,e2 components of the ellipticity vector
			in the survey shear-catalogue convention
		phi : ndarray
			if e 1D: angle between semimajor/semiminor axis and separation vector;
			if 2D: angle of the projected separation vector in the internal (east, north) frame,
			arctan2(north, east)

		Returns
		-------
		ndarray
			e_+ and e_x

		"""
		if len(np.shape(e)) > 1:
			e_plus = e[:, 0] * np.cos(2 * phi) - e[:, 1] * np.sin(2 * phi)
			e_cross = e[:, 0] * np.sin(2 * phi) + e[:, 1] * np.cos(2 * phi)
		else:
			e_plus, e_cross = e * np.cos(2 * phi), e * np.sin(2 * phi)
		return e_plus, e_cross

	@staticmethod
	def get_random_pairs(rp_max, rp_min, pi_max, pi_min, L3, corrtype, Num_position, Num_shape,
						 num_overlap=0):
		"""Returns analytical value of the number of pairs expected in an r_p, pi bin for a random uniform distribution.
		(Singh et al. 2023)

		Parameters
		----------
		rp_max : float
			Upper bound of projected separation vector bin
		rp_min : float
			Lower bound of projected separation vector bin
		pi_max : float
			Upper bound of line of sight vector bin
		pi_min : float
			Lower bound of line of sight vector bin
		L3 : float or int
			Volume of the simulation box
		corrtype : str
			Correlation type, auto or cross. RR for auto is RR_cross/2.
		Num_position : int
			Number of objects in the position sample.
		Num_shape : int
			Number of objects in the shape sample.
		num_overlap : int, optional
			Number of objects present in *both* samples. A shape galaxy cannot pair with
			itself, and the pair loop drops that self-pair automatically because the
			separation window starts at ``r_min > 0``, so the available pair count is
			``Num_position * Num_shape - num_overlap`` rather than the plain product. Pass 0
			(the default) for genuinely disjoint samples; pass ``Num_shape`` when the shape
			sample is drawn from the position sample, which is the usual IA configuration.
			See :func:`available_pairs`.


		Returns
		-------
		float
			number of pairs in r_p, pi bin

		"""
		num_pairs = available_pairs(Num_position, Num_shape, num_overlap, corrtype)
		# volume is cylindrical pi*dr^2 * height
		return num_pairs * np.pi * (rp_max ** 2 - rp_min ** 2) * abs(pi_max - pi_min) / L3

	def get_random_pairs_r_mur(self, r_max, r_min, mur_max, mur_min, L3, corrtype, Num_position,
							   Num_shape, num_overlap=0):
		"""Returns analytical value of the number of pairs expected in an r, mu_r bin for a random uniform distribution.

		Parameters
		----------
		r_max : float
			Upper bound of separation vector bin
		r_min : float
			Lower bound of separation vector bin
		mur_max : float
			Upper bound of mu_r bin
		mur_min : float
			Lower bound of mu_r bin
		L3 : float
			Volume of the simulation box
		corrtype : str
			Correlation type, auto or cross. RR for auto is RR_cross/2.
		Num_position : int
			Number of objects in the position sample.
		Num_shape : int
			Number of objects in the shape sample.
		num_overlap : int, optional
			Number of objects present in *both* samples. A shape galaxy cannot pair with
			itself, and the pair loop drops that self-pair automatically because the
			separation window starts at ``r_min > 0``, so the available pair count is
			``Num_position * Num_shape - num_overlap`` rather than the plain product. Pass 0
			(the default) for genuinely disjoint samples; pass ``Num_shape`` when the shape
			sample is drawn from the position sample, which is the usual IA configuration.
			See :func:`available_pairs`.


		Returns
		-------
		float
			number of pairs in r, mu_r bin

		"""

		num_pairs = available_pairs(Num_position, Num_shape, num_overlap, corrtype)
		# volume is big cap - small cap for large - small radius
		return abs(num_pairs * 2. * np.pi / 3. * (r_max ** 3 - r_min ** 3)
				   * (mur_max - mur_min) / L3)

	def _measure_w_g_i(self, dataset_name, corr_type="both", return_output=False, jk_group_name=""):
		"""Measures w_gg or w_g+ for a given xi_gi dataset that has been calculated with the _measure_xi_rp_pi_sims
		methods. Integrates over pi bins via sum * dpi. Stores rp, and w_gg or w_g+.

		Parameters
		----------
		dataset_name : str
			Name of xi_gg or xi_g+ dataset and name given to w_gg or w_g+ dataset when stored.
		return_output : bool, optional
			Output is returned if True, saved to file if False. Default value = False
		corr_type : str, optional
			Type of correlation function. Choose from [g+,gg,both]. Default value = "both"
		jk_group_name : str, optional
			Name of subgroup in hdf5 file where jackknife realisations are stored. Default value = ""

		Returns
		-------
		ndarray
			[rp, wgg] or [rp, wg+] if return_output is True

		"""
		if corr_type == "both":
			xi_data = ["xi_g_plus", "xi_gg"]
			wg_data = ["w_g_plus", "w_gg"]
		elif corr_type == "g+":
			xi_data = ["xi_g_plus"]
			wg_data = ["w_g_plus"]
		elif corr_type == "gg":
			xi_data = ["xi_gg"]
			wg_data = ["w_gg"]
		else:
			raise KeyError("Unknown value for corr_type. Choose from [g+, gg, both]")
		for i in np.arange(0, len(xi_data)):
			correlation_data_file = h5py.File(self.output_file_name, "a")
			group = correlation_data_file[f"{self.snap_group}w/{xi_data[i]}/{jk_group_name}"]
			correlation_data = group[dataset_name][:]
			pi = group[dataset_name + "_pi"][:]
			rp = group[dataset_name + "_rp"][:]
			dpi = (self.pi_bins[1:] - self.pi_bins[:-1])
			pi_bins = self.pi_bins[:-1] + abs(dpi) / 2.0  # middle of bins
			if sum(np.isin(pi, pi_bins)) == len(pi):
				dpi = np.array([dpi] * len(correlation_data[:, 0]))
				correlation_data = correlation_data * abs(dpi)
			else:
				raise ValueError("Update pi bins in initialisation of object to match xi_g_plus dataset.")
			# xi carries NaN/inf in bins with zero empirical RR (undefined estimator, already
			# warned); the pi-integral over such a bin is legitimately NaN, so silence the
			# redundant reduce/invalid-value warning.
			with np.errstate(invalid='ignore'):
				w_g_i = np.sum(correlation_data, axis=1)  # sum over pi values
			if return_output:
				output_data = np.array([rp, w_g_i]).transpose()
				correlation_data_file.close()
				return output_data
			else:
				group_out = create_group_hdf5(correlation_data_file,
											  f"{self.snap_group}{wg_data[i]}/{jk_group_name}")
				write_dataset_hdf5(group_out, dataset_name + "_rp", data=rp)
				write_dataset_hdf5(group_out, dataset_name, data=w_g_i)
				correlation_data_file.close()
		return

	def _measure_multipoles(self, dataset_name, corr_type="both", return_output=False, jk_group_name=""):
		"""Measures multipoles for a given xi_g+ or xi_gg measured by _measure_xi_r_pi_sims methods.
		The data assumes xi_g+ and xi_gg to be measured in bins of r and mu_r.

		Parameters
		----------
		dataset_name : str
			Name of xi_gg or xi_g+ dataset and name given to multipoles dataset when stored.
		corr_type : str, optional
			Type of correlation function. Choose from [g+,gg,both]. Default value = "both"
		return_output : bool, optional
			Output is returned if True, saved to file if False. Default value = False.
		jk_group_name : str, optional
			Name of subgroup in hdf5 file where jackknife realisations are stored. Default value = ""

		Returns
		-------
		ndarray
			[r, multipoles_gg] or [r, multipoles_g+] if return_output is True
		"""
		correlation_data_file = h5py.File(self.output_file_name, "a")
		if corr_type == "g+":  # '++' (shape-shape) correlations are a planned post-release feature
			group = correlation_data_file[f"{self.snap_group}multipoles/xi_g_plus/{jk_group_name}"]
			correlation_data_list = [group[dataset_name][:]]  # xi_g+ in grid of r,mur
			r_list = [group[dataset_name + "_r"][:]]
			mu_r_list = [group[dataset_name + "_mu_r"][:]]
			sab_list = [2]
			l_list = sab_list
			corr_type_list = ["g_plus"]
		elif corr_type == "gg":
			group = correlation_data_file[f"{self.snap_group}multipoles/xi_gg/{jk_group_name}"]
			correlation_data_list = [group[dataset_name][:]]  # xi_g+ in grid of rp,pi
			r_list = [group[dataset_name + "_r"][:]]
			mu_r_list = [group[dataset_name + "_mu_r"][:]]
			sab_list = [0]
			l_list = sab_list
			corr_type_list = ["gg"]
		elif corr_type == "both":
			group = correlation_data_file[f"{self.snap_group}multipoles/xi_g_plus/{jk_group_name}"]
			correlation_data_list = [group[dataset_name][:]]  # xi_g+ in grid of rp,pi
			r_list = [group[dataset_name + "_r"][:]]
			mu_r_list = [group[dataset_name + "_mu_r"][:]]
			group = correlation_data_file[f"{self.snap_group}multipoles/xi_gg/{jk_group_name}"]
			correlation_data_list.append(group[dataset_name][:])  # xi_g+ in grid of rp,pi
			r_list.append(group[dataset_name + "_r"][:])
			mu_r_list.append(group[dataset_name + "_mu_r"][:])
			sab_list = [2, 0]
			l_list = sab_list
			corr_type_list = ["g_plus", "gg"]
		else:
			raise KeyError("Unknown value for corr_type. Choose from [g+, gg, both]")
		for i in np.arange(0, len(sab_list)):
			corr_type_i = corr_type_list[i]
			correlation_data = correlation_data_list[i]
			r = r_list[i]
			mu_r = mu_r_list[i]
			sab = sab_list[i]
			l = l_list[i]
			mu_r = np.array(list(mu_r) * len(r)).reshape((len(r), len(mu_r)))  # make pi into grid for mu

			r = np.array(list(r) * len(mu_r)).reshape((len(r), len(mu_r)))
			r = r.transpose()
			# Associated Legendre polynomial grid. scipy's lpmn (removed in 1.17) returned a
			# (l+1, sab+1) grid whose [-1, -1] element was order l, degree sab; that value is
			# assoc_legendre_p(degree=sab, order=l, z). The call vectorises over the whole
			# mu_r grid (leading axis is the order, hence [0]); output is bit-identical.
			L = assoc_legendre_p(sab, l, mu_r)[0]
			dmur = (self.mu_r_bins[1:] - self.mu_r_bins[:-1])
			dmu_r_array = np.array(list(dmur) * len(r)).reshape((len(r), len(dmur)))
			# correlation_data carries NaN/inf in bins with zero empirical RR (the estimator
			# is undefined there and the user was already warned); the integral over such a
			# bin is legitimately NaN, so silence the redundant reduce/invalid-value warnings.
			with np.errstate(invalid='ignore'):
				multipoles = (
						(2 * l + 1)
						/ 2.0
						* math.factorial(l - sab)
						/ math.factorial(l + sab)
						* L
						* correlation_data
						* dmu_r_array
				)
				multipoles = np.sum(multipoles, axis=1)
			dsep = (self.r_bins[1:] - self.r_bins[:-1]) / 2.0
			separation = self.r_bins[:-1] + abs(dsep)  # middle of bins
			if return_output:
				correlation_data_file.close()
				return np.array([separation, multipoles]).transpose()
			else:
				group_out = create_group_hdf5(
					correlation_data_file, f"{self.snap_group}multipoles_{corr_type_i}/{jk_group_name}"
				)
				write_dataset_hdf5(group_out, dataset_name + "_r", data=separation)
				write_dataset_hdf5(group_out, dataset_name, data=multipoles)
		correlation_data_file.close()
		return

	def _obs_estimator(self, corr_type, IA_estimator, dataset_name, num_samples,
					   jk_group_name=""):
		"""Reads various components of xi and combines into correct estimator for cluster or galaxy
		lightcone alignment correlations. It then writes the xi_gg or xi_g+ in the correct place in the output file.

		Parameters
		----------
		corr_type : list of 2 str elements
			First element: ['gg', 'g+', 'both'], second: 'w' or 'multipoles'
		IA_estimator : str
			Chooser from 'clusters' or 'galaxies' for different estimator definition.
		dataset_name : str
			Name of the dataset
		num_samples : dict
			Dictionary of samples sizes for position, shape and random samples. Keywords: D, S, R_D, R_S
		jk_group_name : str
			Name of subgroup in hdf5 file where jackknife realisations are stored. Default value = ""

		Returns
		-------

		"""
		output_file = h5py.File(self.output_file_name, "a")
		group_gg = output_file[f"{self.snap_group}{corr_type[1]}/xi_gg/{jk_group_name}"]
		if corr_type[0] == "g+" or corr_type[0] == "both":
			group_gp = output_file[
				f"{self.snap_group}{corr_type[1]}/xi_g_plus/{jk_group_name}"]
			SpD = group_gp[f"{dataset_name}_SplusD"][:]
			SpD /= max(num_samples["S"] * num_samples["D"] - num_samples["D_S"], 1)
			SpR = group_gp[f"{dataset_name}_SplusR"][:]
			SpR /= max(num_samples["S"] * num_samples["R_D"], 1)
			if jk_group_name == "":  # cross (parity null test) only for the full sample
				group_gc = output_file[f"{self.snap_group}{corr_type[1]}/xi_g_cross/"]
				ScD = group_gc[f"{dataset_name}_ScrossD"][:]
				ScD /= max(num_samples["S"] * num_samples["D"] - num_samples["D_S"], 1)
				ScR = group_gc[f"{dataset_name}_ScrossR"][:]
				ScR /= max(num_samples["S"] * num_samples["R_D"], 1)
		if corr_type[0] == "gg" or corr_type[0] == "both" or IA_estimator == "clusters":
			SR = group_gg[f"{dataset_name}_SR"][:]
			SR /= max(num_samples["S"] * num_samples["R_D"], 1)
		if corr_type[0] == "gg" or corr_type[0] == "both":
			RD = group_gg[f"{dataset_name}_RD"][:]
			RD /= max(num_samples["D"] * num_samples["R_S"], 1)
		if IA_estimator == 'clusters' or corr_type[0] == "gg" or corr_type[0] == "both":
			DD = group_gg[f"{dataset_name}_DD"][:]
			DD /= max(num_samples["D"] * num_samples["S"] - num_samples["D_S"], 1)
			DD_denom = DD.copy()  # guard for the clusters division; raw DD keeps 0 in the gg numerator
			DD_denom[DD_denom == 0] = 1.
		if IA_estimator == "galaxies" or corr_type[0] == "gg" or corr_type[0] == "both":
			RR = group_gg[f"{dataset_name}_RR"][:]
			if jk_group_name == "" and np.any(RR == 0):
				warnings.warn(
					f"{int(np.sum(RR == 0))} bin(s) of '{dataset_name}' contain zero random-random pairs; "
					"the estimator is undefined (NaN) there and any w/multipole integral over these bins "
					"will be NaN. Increase the number of randoms to fill all bins.", RuntimeWarning)
			RR /= max(num_samples["R_D"] * num_samples["R_S"], 1)

		# Bins with zero empirical RR (or SR) divide to NaN/inf on purpose: the estimator
		# is undefined there. The zero-RR RuntimeWarning above already tells the user, so
		# silence the redundant numpy divide/invalid-value warnings from these divisions.
		with np.errstate(invalid='ignore', divide='ignore'):
			if IA_estimator == "clusters":
				if corr_type[0] == "g+" or corr_type[0] == "both":
					correlation_gp = SpD / DD_denom - SpR / SR
					write_dataset_hdf5(group_gp, dataset_name, correlation_gp)
					if jk_group_name == "":
						correlation_gc = ScD / DD_denom - ScR / SR
						write_dataset_hdf5(group_gc, dataset_name, correlation_gc)
				if corr_type[0] == "gg" or corr_type[0] == "both":
					correlation_gg = (DD - RD - SR) / RR + 1
					write_dataset_hdf5(group_gg, dataset_name, correlation_gg)
			elif IA_estimator == "galaxies":
				if corr_type[0] == "g+" or corr_type[0] == "both":
					correlation_gp = (SpD - SpR) / RR
					write_dataset_hdf5(group_gp, dataset_name, correlation_gp)
					if jk_group_name == "":
						correlation_gc = (ScD - ScR) / RR
						write_dataset_hdf5(group_gc, dataset_name, correlation_gc)
				if corr_type[0] == "gg" or corr_type[0] == "both":
					correlation_gg = (DD - RD - SR) / RR + 1
					write_dataset_hdf5(group_gg, dataset_name, correlation_gg)
			else:
				raise ValueError("Unknown input for IA_estimator, choose from [clusters, galaxies].")
		output_file.close()
		return

__init__(data, output_file_name, simulation=None, snapshot=None, separation_limits=[0.1, 20.0], num_bins_r=8, num_bins_pi=20, pi_max=None, boxsize=None, periodicity=True)

The init method of the MeasureIABase class.

Parameters:
  • data (dict or NoneType) –
    Dictionary with data needed for calculations.
    For cartesian coordinates, the keywords are:
    'Position' and 'Position_shape_sample': (N_p,3), (N_s,3) ndarrays with the x, y, z coordinates
    of the N_p, N_s objects in the position and shape samples, respectively.
    'Axis_Direction': (N_s,2) ndarray with the two elements of the unit vectors describing the
    axis direction of the projected axis of the object shape.
    'LOS': index referring back to the column number in the 'Position' samples that contains the
    line-of-sight coordinate. (e.g. if the shapes are projected over the z-axis, LOS=2)
    'q': (N_s) array containing the axis ratio q=b/a for each object in the shape sample.
    For lightcone coordinates, the keywords are:
    'Redshift' and 'Redshift_shape_sample': (N_p) and (N_s) ndarray with redshifts of position and shape samples.
    'RA' and 'RA_shape_sample': (N_p) and (N_s) ndarray with RA coordinate of position and shape samples.
    'DEC' and 'DEC_shape_sample': (N_p) and (N_s) ndarray with DEC coordinate of position and shape samples.
    'e1' and 'e2': (N_s) arrays with the two ellipticity components e1 and e2 of the shape sample objects.
    
  • output_file_name (str) –
    Name and filepath of the file where the output should be stored. Needs to be hdf5-type.
    
  • simulation (str or NoneType, default: None ) –
    Indicator of simulation, obtaining correct boxsize in cMpc/h automatically. 
    Choose from [TNG100, TNG100_2, TNG300, EAGLE, HorizonAGN, FLAMINGO_L1, FLAMINGO_L2p8, COLIBRE_L400,
    COLIBRE_L200].
    Default is None, in which case boxsize needs to be added manually; or in the case of observational data, 
    the pi_max.
    
  • snapshot (int or str or NoneType, default: None ) –
    Number of the snapshot, which, if given, will ensure that the output file to contains a group
    'Snapshot_[snapshot]'. If None, the group is omitted from the output file structure. Default is None.
    
  • separation_limits (iterable of 2 entries, default: [0.1, 20.0] ) –
    Bounds of the (projected) separation vector length bins in cMpc/h (so, r or r_p). Default is [0.1,20].
    
  • num_bins_r (int, default: 8 ) –
    Number of bins for (projected) separation vector. Default is 8.
    
  • num_bins_pi (int, default: 20 ) –
    Number of bins for line of sight (LOS) vector, pi or mu_r when multipoles are measured. Default is 20.
    
  • pi_max (int or float, default: None ) –
    Bound for line of sight bins. Bounds will be [-pi_max, pi_max]. Default is None, in which case half the
    boxsize will be used.
    
  • boxsize (int or float or NoneType, default: None ) –
    If simulation is not included in SimInfo, a manual boxsize can be added here. Make sure simulation=None
    and the boxsize units are equal to those in the data dictionary. Default is None.
    
  • periodicity (bool, default: True ) –
    If True, the periodic boundary conditions of the simulation box are taken into account. If False, they are
    ignored. Note that because this code used analytical randoms for the simulations, the correlations will not
    be correct in this case and only DD and S+D terms should be studied. Non-periodic randoms can be measured by
    providing random data to the code and considering the DD term that is measured. Correlations and covariance
    matrix will need to be reconstructed from parts. [Please add a request for teh integration of this method of
    this if you would like to use this option often.] Default is True.
    
Source code in src/measureia/measure_IA_base.py
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def __init__(
		self,
		data,
		output_file_name,
		simulation=None,
		snapshot=None,
		separation_limits=[0.1, 20.0],
		num_bins_r=8,
		num_bins_pi=20,
		pi_max=None,
		boxsize=None,
		periodicity=True,
):
	"""
	The __init__ method of the MeasureIABase class.

	Parameters
	----------
	data : dict or NoneType
		Dictionary with data needed for calculations.
		For cartesian coordinates, the keywords are:
		'Position' and 'Position_shape_sample': (N_p,3), (N_s,3) ndarrays with the x, y, z coordinates
		of the N_p, N_s objects in the position and shape samples, respectively.
		'Axis_Direction': (N_s,2) ndarray with the two elements of the unit vectors describing the
		axis direction of the projected axis of the object shape.
		'LOS': index referring back to the column number in the 'Position' samples that contains the
		line-of-sight coordinate. (e.g. if the shapes are projected over the z-axis, LOS=2)
		'q': (N_s) array containing the axis ratio q=b/a for each object in the shape sample.
		For lightcone coordinates, the keywords are:
		'Redshift' and 'Redshift_shape_sample': (N_p) and (N_s) ndarray with redshifts of position and shape samples.
		'RA' and 'RA_shape_sample': (N_p) and (N_s) ndarray with RA coordinate of position and shape samples.
		'DEC' and 'DEC_shape_sample': (N_p) and (N_s) ndarray with DEC coordinate of position and shape samples.
		'e1' and 'e2': (N_s) arrays with the two ellipticity components e1 and e2 of the shape sample objects.
	output_file_name : str
		Name and filepath of the file where the output should be stored. Needs to be hdf5-type.
	simulation : str or NoneType, optional
		Indicator of simulation, obtaining correct boxsize in cMpc/h automatically. 
		Choose from [TNG100, TNG100_2, TNG300, EAGLE, HorizonAGN, FLAMINGO_L1, FLAMINGO_L2p8, COLIBRE_L400,
		COLIBRE_L200].
		Default is None, in which case boxsize needs to be added manually; or in the case of observational data, 
		the pi_max.
	snapshot : int or str or NoneType, optional
		Number of the snapshot, which, if given, will ensure that the output file to contains a group
		'Snapshot_[snapshot]'. If None, the group is omitted from the output file structure. Default is None.
	separation_limits : iterable of 2 entries, optional
		Bounds of the (projected) separation vector length bins in cMpc/h (so, r or r_p). Default is [0.1,20].
	num_bins_r : int, optional
		Number of bins for (projected) separation vector. Default is 8.
	num_bins_pi : int, optional
		Number of bins for line of sight (LOS) vector, pi or mu_r when multipoles are measured. Default is 20.
	pi_max : int or float, optional
		Bound for line of sight bins. Bounds will be [-pi_max, pi_max]. Default is None, in which case half the
		boxsize will be used.
	boxsize : int or float or NoneType, optional
		If simulation is not included in SimInfo, a manual boxsize can be added here. Make sure simulation=None
		and the boxsize units are equal to those in the data dictionary. Default is None.
	periodicity : bool, optional
		If True, the periodic boundary conditions of the simulation box are taken into account. If False, they are
		ignored. Note that because this code used analytical randoms for the simulations, the correlations will not
		be correct in this case and only DD and S+D terms should be studied. Non-periodic randoms can be measured by
		providing random data to the code and considering the DD term that is measured. Correlations and covariance
		matrix will need to be reconstructed from parts. [Please add a request for teh integration of this method of
		this if you would like to use this option often.] Default is True.

	"""
	SimInfo.__init__(self, simulation, snapshot, boxsize)
	# --- validate numeric configuration parameters ---
	if not (isinstance(num_bins_r, (int, np.integer)) and not isinstance(num_bins_r, bool) and num_bins_r >= 1):
		raise ValueError(f"num_bins_r must be an integer >= 1, got {num_bins_r!r}.")
	if not (isinstance(num_bins_pi, (int, np.integer)) and not isinstance(num_bins_pi, bool) and num_bins_pi >= 1):
		raise ValueError(f"num_bins_pi must be an integer >= 1, got {num_bins_pi!r}.")
	try:
		r_min_check, r_max_check = separation_limits
	except (TypeError, ValueError):
		raise ValueError(
			f"separation_limits must be a length-2 sequence [r_min, r_max], got {separation_limits!r}.")
	if not (0 < r_min_check < r_max_check):
		raise ValueError(
			f"separation_limits must satisfy 0 < r_min < r_max, got {separation_limits}.")
	if self.boxsize is not None and self.boxsize is not False and not (self.boxsize > 0):
		raise ValueError(f"boxsize must be > 0, got {self.boxsize!r}.")
	if pi_max is not None and not (pi_max > 0):
		raise ValueError(f"pi_max must be > 0, got {pi_max!r}.")
	self.data = data
	self.output_file_name = output_file_name
	self.periodicity = periodicity
	if periodicity:
		periodic = "periodic "
	else:
		periodic = ""
	try:
		self.Num_position = len(data["Position"])  # number of halos in position sample
		self.Num_shape = len(data["Position_shape_sample"])  # number of halos in shape sample
	except (KeyError, TypeError):  # TypeError: data is None
		try:
			self.Num_position = len(data["RA"])
			self.Num_shape = len(data["RA_shape_sample"])
		except (KeyError, TypeError):
			self.Num_position = 0
			self.Num_shape = 0
			print("Warning: no Position or Position_shape_sample given.")
	if self.Num_position > 0:
		if "weight" not in self.data:
			self.data["weight"] = np.ones(self.Num_position)
		if "weight_shape_sample" not in self.data:
			self.data["weight_shape_sample"] = np.ones(self.Num_shape)
	self.r_min = separation_limits[0]  # cMpc/h
	self.r_max = separation_limits[1]  # cMpc/h
	self.num_bins_r = num_bins_r
	self.num_bins_pi = num_bins_pi
	self.r_bins = np.logspace(np.log10(self.r_min), np.log10(self.r_max), self.num_bins_r + 1)
	if pi_max == None:
		if self.L_0p5 is None:
			raise ValueError(
				"Both pi_max and boxsize are None. Provide input on one of them to determine the integration limit pi_max.")
		else:
			pi_max = self.L_0p5
	self.pi_bins = np.linspace(-pi_max, pi_max, self.num_bins_pi + 1)
	self.mu_r_bins = np.linspace(-1, 1, self.num_bins_pi + 1)
	if simulation == False:
		print(f"MeasureIA object initialised with:\n \
				observational data.\n \
				There are {self.Num_shape} galaxies in the shape sample and {self.Num_position} galaxies in the position sample.\n\
				The separation bin edges are given by {self.r_bins} Mpc.\n \
				There are {num_bins_r} r or r_p bins and {num_bins_pi} pi bins.\n \
				The maximum pi used for binning is {pi_max}.\n \
				The data will be written to {self.output_file_name}")
	else:
		print(f"MeasureIA object initialised with:\n \
		simulation {simulation} that has a {periodic}boxsize of {self.boxsize} cMpc/h.\n \
		There are {self.Num_shape} galaxies in the shape sample and {self.Num_position} galaxies in the position sample.\n\
		The separation bin edges are given by {self.r_bins} cMpc/h.\n \
		There are {num_bins_r} r or r_p bins and {num_bins_pi} pi bins.\n \
		The maximum pi used for binning is {pi_max}.\n \
		The data will be written to {self.output_file_name}")
	return

calculate_dot_product_arrays(a1, a2) staticmethod

Calculates the dot product over 2 2D arrays across axis 1 so that dot_product[i] = np.dot(a1[i],a2[i])

Parameters:
  • a1 (ndarray) –
    First array
    
  • a2 (ndarray) –
    Second array
    
Returns:
  • ndarray

    Dot product of columns of arrays

Source code in src/measureia/measure_IA_base.py
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@staticmethod
def calculate_dot_product_arrays(a1, a2):
	"""Calculates the dot product over 2 2D arrays across axis 1 so that dot_product[i] = np.dot(a1[i],a2[i])

	Parameters
	----------
	a1 : ndarray
		First array
	a2 : ndarray
		Second array

	Returns
	-------
	ndarray
		Dot product of columns of arrays

	"""
	dot_product = np.zeros(np.shape(a1)[0])
	for i in np.arange(0, np.shape(a1)[1]):
		dot_product += a1[:, i] * a2[:, i]
	return dot_product

get_ellipticity(e, phi) staticmethod

Calculates the radial (+) and cross (x) components of the ellipticity with respect to the separation vector, following the intrinsic-alignment sign convention: e_+ > 0 means the major axis points along the separation vector (radial alignment), so radial alignment gives w_g+ > 0.

For 2D input, e1 and e2 must follow the standard survey shear-catalogue convention (components defined on the local (RA, DEC) axes as delivered by e.g. lensfit/metacal-style catalogues and expected by TreeCorr). Note that the IA e_+ has the opposite sign to the lensing tangential shear: e_+ = -gamma_t.

Parameters:
  • e (ndarray) –
    if 1D: size of the ellipticity vector; if 2D: e1,e2 components of the ellipticity vector
    in the survey shear-catalogue convention
    
  • phi (ndarray) –
    if e 1D: angle between semimajor/semiminor axis and separation vector;
    if 2D: angle of the projected separation vector in the internal (east, north) frame,
    arctan2(north, east)
    
Returns:
  • ndarray

    e_+ and e_x

Source code in src/measureia/measure_IA_base.py
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@staticmethod
def get_ellipticity(e, phi):
	"""Calculates the radial (+) and cross (x) components of the ellipticity with respect to the
	separation vector, following the intrinsic-alignment sign convention: e_+ > 0 means the
	major axis points along the separation vector (radial alignment), so radial alignment
	gives w_g+ > 0.

	For 2D input, e1 and e2 must follow the standard survey shear-catalogue convention
	(components defined on the local (RA, DEC) axes as delivered by e.g. lensfit/metacal-style
	catalogues and expected by TreeCorr). Note that the IA e_+ has the opposite sign to the
	lensing tangential shear: e_+ = -gamma_t.

	Parameters
	----------
	e : ndarray
		if 1D: size of the ellipticity vector; if 2D: e1,e2 components of the ellipticity vector
		in the survey shear-catalogue convention
	phi : ndarray
		if e 1D: angle between semimajor/semiminor axis and separation vector;
		if 2D: angle of the projected separation vector in the internal (east, north) frame,
		arctan2(north, east)

	Returns
	-------
	ndarray
		e_+ and e_x

	"""
	if len(np.shape(e)) > 1:
		e_plus = e[:, 0] * np.cos(2 * phi) - e[:, 1] * np.sin(2 * phi)
		e_cross = e[:, 0] * np.sin(2 * phi) + e[:, 1] * np.cos(2 * phi)
	else:
		e_plus, e_cross = e * np.cos(2 * phi), e * np.sin(2 * phi)
	return e_plus, e_cross

get_random_pairs(rp_max, rp_min, pi_max, pi_min, L3, corrtype, Num_position, Num_shape, num_overlap=0) staticmethod

Returns analytical value of the number of pairs expected in an r_p, pi bin for a random uniform distribution. (Singh et al. 2023)

Parameters:
  • rp_max (float) –
    Upper bound of projected separation vector bin
    
  • rp_min (float) –
    Lower bound of projected separation vector bin
    
  • pi_max (float) –
    Upper bound of line of sight vector bin
    
  • pi_min (float) –
    Lower bound of line of sight vector bin
    
  • L3 (float or int) –
    Volume of the simulation box
    
  • corrtype (str) –
    Correlation type, auto or cross. RR for auto is RR_cross/2.
    
  • Num_position (int) –
    Number of objects in the position sample.
    
  • Num_shape (int) –
    Number of objects in the shape sample.
    
  • num_overlap (int, default: 0 ) –
    Number of objects present in *both* samples. A shape galaxy cannot pair with
    itself, and the pair loop drops that self-pair automatically because the
    separation window starts at ``r_min > 0``, so the available pair count is
    ``Num_position * Num_shape - num_overlap`` rather than the plain product. Pass 0
    (the default) for genuinely disjoint samples; pass ``Num_shape`` when the shape
    sample is drawn from the position sample, which is the usual IA configuration.
    See :func:`available_pairs`.
    
Returns:
  • float

    number of pairs in r_p, pi bin

Source code in src/measureia/measure_IA_base.py
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@staticmethod
def get_random_pairs(rp_max, rp_min, pi_max, pi_min, L3, corrtype, Num_position, Num_shape,
					 num_overlap=0):
	"""Returns analytical value of the number of pairs expected in an r_p, pi bin for a random uniform distribution.
	(Singh et al. 2023)

	Parameters
	----------
	rp_max : float
		Upper bound of projected separation vector bin
	rp_min : float
		Lower bound of projected separation vector bin
	pi_max : float
		Upper bound of line of sight vector bin
	pi_min : float
		Lower bound of line of sight vector bin
	L3 : float or int
		Volume of the simulation box
	corrtype : str
		Correlation type, auto or cross. RR for auto is RR_cross/2.
	Num_position : int
		Number of objects in the position sample.
	Num_shape : int
		Number of objects in the shape sample.
	num_overlap : int, optional
		Number of objects present in *both* samples. A shape galaxy cannot pair with
		itself, and the pair loop drops that self-pair automatically because the
		separation window starts at ``r_min > 0``, so the available pair count is
		``Num_position * Num_shape - num_overlap`` rather than the plain product. Pass 0
		(the default) for genuinely disjoint samples; pass ``Num_shape`` when the shape
		sample is drawn from the position sample, which is the usual IA configuration.
		See :func:`available_pairs`.


	Returns
	-------
	float
		number of pairs in r_p, pi bin

	"""
	num_pairs = available_pairs(Num_position, Num_shape, num_overlap, corrtype)
	# volume is cylindrical pi*dr^2 * height
	return num_pairs * np.pi * (rp_max ** 2 - rp_min ** 2) * abs(pi_max - pi_min) / L3

get_random_pairs_r_mur(r_max, r_min, mur_max, mur_min, L3, corrtype, Num_position, Num_shape, num_overlap=0)

Returns analytical value of the number of pairs expected in an r, mu_r bin for a random uniform distribution.

Parameters:
  • r_max (float) –
    Upper bound of separation vector bin
    
  • r_min (float) –
    Lower bound of separation vector bin
    
  • mur_max (float) –
    Upper bound of mu_r bin
    
  • mur_min (float) –
    Lower bound of mu_r bin
    
  • L3 (float) –
    Volume of the simulation box
    
  • corrtype (str) –
    Correlation type, auto or cross. RR for auto is RR_cross/2.
    
  • Num_position (int) –
    Number of objects in the position sample.
    
  • Num_shape (int) –
    Number of objects in the shape sample.
    
  • num_overlap (int, default: 0 ) –
    Number of objects present in *both* samples. A shape galaxy cannot pair with
    itself, and the pair loop drops that self-pair automatically because the
    separation window starts at ``r_min > 0``, so the available pair count is
    ``Num_position * Num_shape - num_overlap`` rather than the plain product. Pass 0
    (the default) for genuinely disjoint samples; pass ``Num_shape`` when the shape
    sample is drawn from the position sample, which is the usual IA configuration.
    See :func:`available_pairs`.
    
Returns:
  • float

    number of pairs in r, mu_r bin

Source code in src/measureia/measure_IA_base.py
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def get_random_pairs_r_mur(self, r_max, r_min, mur_max, mur_min, L3, corrtype, Num_position,
						   Num_shape, num_overlap=0):
	"""Returns analytical value of the number of pairs expected in an r, mu_r bin for a random uniform distribution.

	Parameters
	----------
	r_max : float
		Upper bound of separation vector bin
	r_min : float
		Lower bound of separation vector bin
	mur_max : float
		Upper bound of mu_r bin
	mur_min : float
		Lower bound of mu_r bin
	L3 : float
		Volume of the simulation box
	corrtype : str
		Correlation type, auto or cross. RR for auto is RR_cross/2.
	Num_position : int
		Number of objects in the position sample.
	Num_shape : int
		Number of objects in the shape sample.
	num_overlap : int, optional
		Number of objects present in *both* samples. A shape galaxy cannot pair with
		itself, and the pair loop drops that self-pair automatically because the
		separation window starts at ``r_min > 0``, so the available pair count is
		``Num_position * Num_shape - num_overlap`` rather than the plain product. Pass 0
		(the default) for genuinely disjoint samples; pass ``Num_shape`` when the shape
		sample is drawn from the position sample, which is the usual IA configuration.
		See :func:`available_pairs`.


	Returns
	-------
	float
		number of pairs in r, mu_r bin

	"""

	num_pairs = available_pairs(Num_position, Num_shape, num_overlap, corrtype)
	# volume is big cap - small cap for large - small radius
	return abs(num_pairs * 2. * np.pi / 3. * (r_max ** 3 - r_min ** 3)
			   * (mur_max - mur_min) / L3)