Source code for nipy.labs.utils.zscore

from __future__ import absolute_import
# emacs: -*- mode: python; py-indent-offset: 4; indent-tabs-mode: nil -*-
# vi: set ft=python sts=4 ts=4 sw=4 et:
import numpy as np
import scipy.stats

TINY = 1e-15


def zscore(pvalue):
    """ Return the z-score corresponding to a given p-value.
    """
    pvalue = np.minimum(np.maximum(pvalue, TINY), 1. - TINY)
    z = scipy.stats.norm.isf(pvalue)
    return z