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[ascl:2404.006] PolyBin3D: Binned polyspectrum estimation for 3D large-scale structure

PolyBin3D estimates the binned power spectrum and bispectrum for 3D fields such as the distributions of matter and galaxies. For each statistic, two estimators are available: the standard (ideal) estimators, which do not take into account the mask, and window-deconvolved estimators. In the second case, the computation of a Fisher matrix is required; this depends on binning and the mask, but does not need to be recomputed for each new simulation. PolyBin3D supports GPU acceleration using JAX. It is a sister code to PolyBin (ascl:2307.020), which computes the polyspectra of data on the two-sphere, and is a modern reimplementation of the former Spectra-Without-Windows (ascl:2108.011) code.

[ascl:2404.007] WignerFamilies: Compute families of wigner symbols with recurrence relations

WignerFamilies generates families of Wigner 3j and 6j symbols by recurrence relation. These exact methods are orders of magnitude more efficient than strategies such as prime factorization for problems which require every non-trivial symbol in a family, and are very useful for large quantum numbers. WignerFamilies is thread-safe and very fast, beating the standard Fortran routine DRC3JJ from SLATEC by a factor of 2-4.

[ascl:2404.008] LensIt: CMB lensing delensing tools

LensIt enables CMB lensing and CMB delensing using the flat-sky approximation. The package can find the maximum posterior estimation of CMB lensing deflection maps from temperature and/or polarization maps and perform Wiener filtering of masked CMB data and allow for inhomogenous noise, including lensing deflections, using a multigrid preconditioner. It contains fast and accurate simulation libraries for lensed CMB skies, and standard quadratic estimator lensing reconstruction tools. LensIt also includes CMB internal delensing tools, including internal delensing biases calculation for temperature and/or polarization maps.

[ascl:2404.009] superABC: Cosmological constraints from SN light curves using Approximate Bayesian Computation

The superABC sampling method obtains cosmological constraints from supernova light curves using Approximate Bayesian Computation (ABC) without any likelihood assumptions. It provides an interface to two forward model simulations, SNCosmo (ascl:1611.017) and SNANA (ascl:1010.027), for supernova cosmology.

[ascl:2404.010] Panphasia: Create cosmological and resimulation initial conditions

Panphasia computes a very large realization of a Gaussian white noise field. The field has a hierarchical structure based on an octree geometry with 50 octree levels fully populated. The code sets up Gaussian initial conditions for cosmological simulations and resimulations of structure formation. Panphasia provides an easy way to publish the linear phases used to set up cosmological simulation initial conditions; publishing phases enriches the literature and makes it easier to reproduce and extend published simulation work.

[ascl:2404.011] BayeSN: NumPyro implementation of BayeSN

BayeSN performs hierarchical Bayesian SED modeling of type Ia supernova light curves. This probabilistic optical-NIR SED model analyzes the population distribution of physical properties as well as cosmology-independent distance estimation for individual SNe. BayeSN is built with NumPyro and Jax (ascl:2111.002) and provides support for GPU acceleration.

[ascl:2404.012] EffectiveHalos: Matter power spectrum and cluster counts covariance modeler

EffectiveHalos provides models of the real-space matter power spectrum, based on a combination of the Halo Model and Effective Field Theory, which are 1% accurate up to k = 1 h/Mpc, across a range of cosmologies, including those with massive neutrinos. It can additionally compute accurate halo count covariances (including a model of halo exclusion), both alone and in combination with the matter power spectrum.

[ascl:2404.013] Meanoffset: Photometric image alignment with row and column means

Meanoffset performs astronomical image alignment. The code uses the means of the rows and columns of an original image for alignment and finds the optimal offset corresponding to the maximum similarity by comparing different offsets between images. The similarity is evaluated by the standard deviation of the quotient divided by the means. The code is fast and robust.

[ascl:2404.014] astroNN: Deep learning for astronomers with Tensorflow

astroNN creates neural networks for deep learning using Keras for model and training prototyping while taking advantage of Tensorflow's flexibility. It contains tools for use with APOGEE, Gaia and LAMOST data, though is primarily designed to apply neural nets on APOGEE spectra analysis and predict luminosity from spectra using data from Gaia parallax with reasonable uncertainty from Bayesian Neural Net. astroNN can handle 2D and 2D colored images, and the package contains custom loss functions and layers compatible with Tensorflow or Keras with Tensorflow backend to deal with incomplete labels. The code contains demo for implementing Bayesian Neural Net with Dropout Variational Inference for reasonable uncertainty estimation and other neural nets.

[ascl:2404.015] EBWeyl: Compute the electric and magnetic parts of the Weyl tensor

EBWeyl computes the electric and magnetic parts of the Weyl tensor, Eαβ and Bαβ, using a 3+1 slicing formulation. The module provides a Finite Differencing class with 4th (default) and 6th order backward, centered, and forward schemes. Periodic boundary conditions are used by default; otherwise, a combination of the 3 schemes is available. It also includes a Weyl class that computes for a given metric the variables of the 3+1 formalism, the spatial Christoffel symbols, spatial Ricci tensor, electric and magnetic parts of the Weyl tensor projected along the normal to the hypersurface and fluid flow, the Weyl scalars and invariant scalars. EBWeyl can also compute the determinant and inverse of a 3x3 or 4x4 matrice in every position of a data box.

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