# Licensed under a 3-clause BSD style license - see LICENSE.rst

from numpy.testing import assert_allclose

from astropy.utils.compat.optional_deps import HAS_PLT, HAS_SCIPY

if HAS_PLT:

import matplotlib.pyplot as plt

import numpy as np

import pytest

from astropy.stats import histogram

from astropy.visualization import hist

@pytest.mark.skipif(not HAS_PLT, reason="requires matplotlib.pyplot")

def test_hist_basic(rseed=0):

rng = np.random.default_rng(rseed)

x = rng.standard_normal(100)

for range in [None, (-2, 2)]:

n1, bins1, patches1 = plt.hist(x, 10, range=range)

n2, bins2, patches2 = hist(x, 10, range=range)

assert_allclose(n1, n2)

assert_allclose(bins1, bins2)

@pytest.mark.skipif(not HAS_PLT, reason="requires matplotlib.pyplot")

def test_hist_specify_ax(rseed=0):

rng = np.random.default_rng(rseed)

x = rng.standard_normal(100)

fig, ax = plt.subplots(2)

n1, bins1, patches1 = hist(x, 10, ax=ax[0])

assert patches1[0].axes is ax[0]

n2, bins2, patches2 = hist(x, 10, ax=ax[1])

assert patches2[0].axes is ax[1]

@pytest.mark.skipif(not HAS_PLT, reason="requires matplotlib.pyplot")

def test_hist_autobin(rseed=0):

rng = np.random.default_rng(rseed)

x = rng.standard_normal(100)

# 'knuth' bintype depends on scipy that is optional dependency

if HAS_SCIPY:

bintypes = [10, np.arange(-3, 3, 10), "knuth", "scott", "freedman", "blocks"]

else:

bintypes = [10, np.arange(-3, 3, 10), "scott", "freedman", "blocks"]

for bintype in bintypes:

for range in [None, (-3, 3)]:

n1, bins1 = histogram(x, bintype, range=range)

n2, bins2, patches = hist(x, bintype, range=range)

assert_allclose(n1, n2)

assert_allclose(bins1, bins2)

def test_histogram_pathological_input():

# Regression test for https://github.com/astropy/astropy/issues/7758

# The key feature of the data below is that one of the points is very,

# very different than the rest. That leads to a large number of bins.

data = [

9.99999914e05,

-8.31312483e-03,

6.52755852e-02,

1.43104653e-03,

-2.26311017e-02,

2.82660007e-03,

1.80307521e-02,

9.26294279e-03,

5.06606026e-02,

2.05418011e-03,

]

with pytest.raises(ValueError):

hist(data, bins="freedman", max_bins=10000)