# What’s New in Halotools v0.6?¶

Halotools v0.6 is now available for installation with conda and pip. New features are summarized below. See Full Changelog for details on smaller issues and bug-fixes. See Version v0.x release history for full release history information.

## Quick Installation Verification¶

It is now much faster to verify successful installation of the latest version of halotools. After installing the code, you can now run a targeted subset of unit tests, rather than the entire test suite:

import halotools
halotools.test_installation()


## New Mock Observables¶

There are new functions in the mock_observables sub-package that calculate element-wise radial distances and velocities, radial_distance and radial_distance_and_velocity.

### Jackknife error estimation¶

New functions wp_jackknife and rp_pi_tpcf_jackknife give jackknife error estimation for the wp and rp_pi_tpcf functions.

### Weighted pair counts as a function of (s, mu)¶

New halotools.mock_observables.pair_counters.weighted_npairs_s_mu function gives weighting option for counting pairs in (s, mu) space.

## Utility functions¶

### Matching two distributions for statistical comparison¶

The halotools.utils.distribution_matching_indices function Monte Carlo resamples one distribution until it matches another.

## API Change¶

• The npairs_s_mu function now has a change to the meaning of the mu_bins input argument. This argument should now be interpreted as the conventional mu=cos(theta_LOS) instead of mu=sin(theta_LOS).