Source code for inspirehep.utils.stats

# -*- coding: utf-8 -*-
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# Copyright (C) 2014-2017 CERN.
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from __future__ import absolute_import, division, print_function


def calculate_h_index(citations):
    """
    Calculate the h-index of a citation dictionary.

    An author has h-index X if she has X papers with at least X citations each.
    See: https://en.wikipedia.org/wiki/H-index.

    :param citations: a dictionary in the format {recid: citation_count}
    :return: h-index of the dictionary of citations.
    """
    length = len(citations)

    histogram = [0] * (length + 1)
    for _, count in citations.items():
        histogram[min(count, length) if count else 0] += 1

    sum_ = 0
    for i, count in reversed(list(enumerate(histogram))):
        sum_ += count
        if sum_ >= i:
            return i

    return 0


def calculate_i10_index(citations):
    """
    Calculate the i10-index of a citation dictionary.

    An author has i10-index X if she has X papers with at least 10 citations
    each. See: https://en.wikipedia.org/wiki/H-index#i10-index

    :param citations: a dictionary in the format {recid: citation_count}
    :return: i10-index of the dictionary of citations.
    """
    return len([_ for _, count in citations.items() if count >= 10])