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-rw-r--r--numpy/lib/function_base.py112
-rw-r--r--numpy/lib/histograms.py26
-rw-r--r--numpy/lib/tests/test_function_base.py12
-rw-r--r--numpy/lib/tests/test_histograms.py16
-rw-r--r--numpy/lib/tests/test_twodim_base.py6
-rw-r--r--numpy/lib/twodim_base.py14
6 files changed, 165 insertions, 21 deletions
diff --git a/numpy/lib/function_base.py b/numpy/lib/function_base.py
index 9a680dd55..1a43da8b0 100644
--- a/numpy/lib/function_base.py
+++ b/numpy/lib/function_base.py
@@ -31,7 +31,7 @@ from numpy.core.function_base import add_newdoc
from numpy.lib.twodim_base import diag
from .utils import deprecate
from numpy.core.multiarray import (
- _insert, add_docstring, digitize, bincount, normalize_axis_index,
+ _insert, add_docstring, bincount, normalize_axis_index, _monotonicity,
interp as compiled_interp, interp_complex as compiled_interp_complex
)
from numpy.core.umath import _add_newdoc_ufunc as add_newdoc_ufunc
@@ -4493,3 +4493,113 @@ def append(arr, values, axis=None):
values = ravel(values)
axis = arr.ndim-1
return concatenate((arr, values), axis=axis)
+
+
+def digitize(x, bins, right=False):
+ """
+ Return the indices of the bins to which each value in input array belongs.
+
+ ========= ============= ============================
+ `right` order of bins returned index `i` satisfies
+ ========= ============= ============================
+ ``False`` increasing ``bins[i-1] <= x < bins[i]``
+ ``True`` increasing ``bins[i-1] < x <= bins[i]``
+ ``False`` decreasing ``bins[i-1] > x >= bins[i]``
+ ``True`` decreasing ``bins[i-1] >= x > bins[i]``
+ ========= ============= ============================
+
+ If values in `x` are beyond the bounds of `bins`, 0 or ``len(bins)`` is
+ returned as appropriate.
+
+ Parameters
+ ----------
+ x : array_like
+ Input array to be binned. Prior to NumPy 1.10.0, this array had to
+ be 1-dimensional, but can now have any shape.
+ bins : array_like
+ Array of bins. It has to be 1-dimensional and monotonic.
+ right : bool, optional
+ Indicating whether the intervals include the right or the left bin
+ edge. Default behavior is (right==False) indicating that the interval
+ does not include the right edge. The left bin end is open in this
+ case, i.e., bins[i-1] <= x < bins[i] is the default behavior for
+ monotonically increasing bins.
+
+ Returns
+ -------
+ indices : ndarray of ints
+ Output array of indices, of same shape as `x`.
+
+ Raises
+ ------
+ ValueError
+ If `bins` is not monotonic.
+ TypeError
+ If the type of the input is complex.
+
+ See Also
+ --------
+ bincount, histogram, unique, searchsorted
+
+ Notes
+ -----
+ If values in `x` are such that they fall outside the bin range,
+ attempting to index `bins` with the indices that `digitize` returns
+ will result in an IndexError.
+
+ .. versionadded:: 1.10.0
+
+ `np.digitize` is implemented in terms of `np.searchsorted`. This means
+ that a binary search is used to bin the values, which scales much better
+ for larger number of bins than the previous linear search. It also removes
+ the requirement for the input array to be 1-dimensional.
+
+ For monotonically _increasing_ `bins`, the following are equivalent::
+
+ np.digitize(x, bins, right=True)
+ np.searchsorted(bins, x, side='left')
+
+ Note that as the order of the arguments are reversed, the side must be too.
+ The `searchsorted` call is marginally faster, as it does not do any
+ monotonicity checks. Perhaps more importantly, it supports all dtypes.
+
+ Examples
+ --------
+ >>> x = np.array([0.2, 6.4, 3.0, 1.6])
+ >>> bins = np.array([0.0, 1.0, 2.5, 4.0, 10.0])
+ >>> inds = np.digitize(x, bins)
+ >>> inds
+ array([1, 4, 3, 2])
+ >>> for n in range(x.size):
+ ... print(bins[inds[n]-1], "<=", x[n], "<", bins[inds[n]])
+ ...
+ 0.0 <= 0.2 < 1.0
+ 4.0 <= 6.4 < 10.0
+ 2.5 <= 3.0 < 4.0
+ 1.0 <= 1.6 < 2.5
+
+ >>> x = np.array([1.2, 10.0, 12.4, 15.5, 20.])
+ >>> bins = np.array([0, 5, 10, 15, 20])
+ >>> np.digitize(x,bins,right=True)
+ array([1, 2, 3, 4, 4])
+ >>> np.digitize(x,bins,right=False)
+ array([1, 3, 3, 4, 5])
+ """
+ x = _nx.asarray(x)
+ bins = _nx.asarray(bins)
+
+ # here for compatibility, searchsorted below is happy to take this
+ if np.issubdtype(x.dtype, _nx.complexfloating):
+ raise TypeError("x may not be complex")
+
+ mono = _monotonicity(bins)
+ if mono == 0:
+ raise ValueError("bins must be monotonically increasing or decreasing")
+
+ # this is backwards because the arguments below are swapped
+ side = 'left' if right else 'right'
+ if mono == -1:
+ # reverse the bins, and invert the results
+ return len(bins) - _nx.searchsorted(bins[::-1], x, side=side)
+ else:
+ return _nx.searchsorted(bins, x, side=side)
diff --git a/numpy/lib/histograms.py b/numpy/lib/histograms.py
index ad7215504..422b356f7 100644
--- a/numpy/lib/histograms.py
+++ b/numpy/lib/histograms.py
@@ -812,7 +812,8 @@ def histogram(a, bins=10, range=None, normed=None, weights=None,
return n, bin_edges
-def histogramdd(sample, bins=10, range=None, normed=False, weights=None):
+def histogramdd(sample, bins=10, range=None, normed=None, weights=None,
+ density=None):
"""
Compute the multidimensional histogram of some data.
@@ -845,9 +846,14 @@ def histogramdd(sample, bins=10, range=None, normed=False, weights=None):
An entry of None in the sequence results in the minimum and maximum
values being used for the corresponding dimension.
The default, None, is equivalent to passing a tuple of D None values.
+ density : bool, optional
+ If False, the default, returns the number of samples in each bin.
+ If True, returns the probability *density* function at the bin,
+ ``bin_count / sample_count / bin_volume``.
normed : bool, optional
- If False, returns the number of samples in each bin. If True,
- returns the bin density ``bin_count / sample_count / bin_volume``.
+ An alias for the density argument that behaves identically. To avoid
+ confusion with the broken normed argument to `histogram`, `density`
+ should be preferred.
weights : (N,) array_like, optional
An array of values `w_i` weighing each sample `(x_i, y_i, z_i, ...)`.
Weights are normalized to 1 if normed is True. If normed is False,
@@ -961,8 +967,18 @@ def histogramdd(sample, bins=10, range=None, normed=False, weights=None):
core = D*(slice(1, -1),)
hist = hist[core]
- # Normalize if normed is True
- if normed:
+ # handle the aliasing normed argument
+ if normed is None:
+ if density is None:
+ density = False
+ elif density is None:
+ # an explicit normed argument was passed, alias it to the new name
+ density = normed
+ else:
+ raise TypeError("Cannot specify both 'normed' and 'density'")
+
+ if density:
+ # calculate the probability density function
s = hist.sum()
for i in _range(D):
shape = np.ones(D, int)
diff --git a/numpy/lib/tests/test_function_base.py b/numpy/lib/tests/test_function_base.py
index d2a9181db..ba5b90e8c 100644
--- a/numpy/lib/tests/test_function_base.py
+++ b/numpy/lib/tests/test_function_base.py
@@ -1510,6 +1510,18 @@ class TestDigitize(object):
assert_(not isinstance(digitize(b, a, False), A))
assert_(not isinstance(digitize(b, a, True), A))
+ def test_large_integers_increasing(self):
+ # gh-11022
+ x = 2**54 # loses precision in a float
+ assert_equal(np.digitize(x, [x - 1, x + 1]), 1)
+
+ @pytest.mark.xfail(
+ reason="gh-11022: np.core.multiarray._monoticity loses precision")
+ def test_large_integers_decreasing(self):
+ # gh-11022
+ x = 2**54 # loses precision in a float
+ assert_equal(np.digitize(x, [x + 1, x - 1]), 1)
+
class TestUnwrap(object):
diff --git a/numpy/lib/tests/test_histograms.py b/numpy/lib/tests/test_histograms.py
index d22aa5a27..f136b5c81 100644
--- a/numpy/lib/tests/test_histograms.py
+++ b/numpy/lib/tests/test_histograms.py
@@ -547,13 +547,13 @@ class TestHistogramdd(object):
# Check normalization
ed = [[-2, 0, 2], [0, 1, 2, 3], [0, 1, 2, 3]]
- H, edges = histogramdd(x, bins=ed, normed=True)
+ H, edges = histogramdd(x, bins=ed, density=True)
assert_(np.all(H == answer / 12.))
# Check that H has the correct shape.
H, edges = histogramdd(x, (2, 3, 4),
range=[[-1, 1], [0, 3], [0, 4]],
- normed=True)
+ density=True)
answer = np.array([[[0, 1, 0, 0], [0, 0, 1, 0], [1, 0, 0, 0]],
[[0, 1, 0, 0], [0, 0, 1, 0], [0, 0, 1, 0]]])
assert_array_almost_equal(H, answer / 6., 4)
@@ -599,10 +599,10 @@ class TestHistogramdd(object):
def test_weights(self):
v = np.random.rand(100, 2)
hist, edges = histogramdd(v)
- n_hist, edges = histogramdd(v, normed=True)
+ n_hist, edges = histogramdd(v, density=True)
w_hist, edges = histogramdd(v, weights=np.ones(100))
assert_array_equal(w_hist, hist)
- w_hist, edges = histogramdd(v, weights=np.ones(100) * 2, normed=True)
+ w_hist, edges = histogramdd(v, weights=np.ones(100) * 2, density=True)
assert_array_equal(w_hist, n_hist)
w_hist, edges = histogramdd(v, weights=np.ones(100, int) * 2)
assert_array_equal(w_hist, 2 * hist)
@@ -708,7 +708,7 @@ class TestHistogramdd(object):
assert_equal(hist[0, 0], 1)
- def test_normed_non_uniform_2d(self):
+ def test_density_non_uniform_2d(self):
# Defines the following grid:
#
# 0 2 8
@@ -732,14 +732,14 @@ class TestHistogramdd(object):
assert_equal(hist, relative_areas)
# resulting histogram should be uniform, since counts and areas are propotional
- hist, edges = histogramdd((y, x), bins=(y_edges, x_edges), normed=True)
+ hist, edges = histogramdd((y, x), bins=(y_edges, x_edges), density=True)
assert_equal(hist, 1 / (8*8))
- def test_normed_non_uniform_1d(self):
+ def test_density_non_uniform_1d(self):
# compare to histogram to show the results are the same
v = np.arange(10)
bins = np.array([0, 1, 3, 6, 10])
hist, edges = histogram(v, bins, density=True)
- hist_dd, edges_dd = histogramdd((v,), (bins,), normed=True)
+ hist_dd, edges_dd = histogramdd((v,), (bins,), density=True)
assert_equal(hist, hist_dd)
assert_equal(edges, edges_dd[0])
diff --git a/numpy/lib/tests/test_twodim_base.py b/numpy/lib/tests/test_twodim_base.py
index d3a072af3..bf93b4adb 100644
--- a/numpy/lib/tests/test_twodim_base.py
+++ b/numpy/lib/tests/test_twodim_base.py
@@ -208,7 +208,7 @@ class TestHistogram2d(object):
x = array([1, 1, 2, 3, 4, 4, 4, 5])
y = array([1, 3, 2, 0, 1, 2, 3, 4])
H, xed, yed = histogram2d(
- x, y, (6, 5), range=[[0, 6], [0, 5]], normed=True)
+ x, y, (6, 5), range=[[0, 6], [0, 5]], density=True)
answer = array(
[[0., 0, 0, 0, 0],
[0, 1, 0, 1, 0],
@@ -220,11 +220,11 @@ class TestHistogram2d(object):
assert_array_equal(xed, np.linspace(0, 6, 7))
assert_array_equal(yed, np.linspace(0, 5, 6))
- def test_norm(self):
+ def test_density(self):
x = array([1, 2, 3, 1, 2, 3, 1, 2, 3])
y = array([1, 1, 1, 2, 2, 2, 3, 3, 3])
H, xed, yed = histogram2d(
- x, y, [[1, 2, 3, 5], [1, 2, 3, 5]], normed=True)
+ x, y, [[1, 2, 3, 5], [1, 2, 3, 5]], density=True)
answer = array([[1, 1, .5],
[1, 1, .5],
[.5, .5, .25]])/9.
diff --git a/numpy/lib/twodim_base.py b/numpy/lib/twodim_base.py
index cca316e9a..98efba191 100644
--- a/numpy/lib/twodim_base.py
+++ b/numpy/lib/twodim_base.py
@@ -530,7 +530,8 @@ def vander(x, N=None, increasing=False):
return v
-def histogram2d(x, y, bins=10, range=None, normed=False, weights=None):
+def histogram2d(x, y, bins=10, range=None, normed=None, weights=None,
+ density=None):
"""
Compute the bi-dimensional histogram of two data samples.
@@ -560,9 +561,14 @@ def histogram2d(x, y, bins=10, range=None, normed=False, weights=None):
(if not specified explicitly in the `bins` parameters):
``[[xmin, xmax], [ymin, ymax]]``. All values outside of this range
will be considered outliers and not tallied in the histogram.
+ density : bool, optional
+ If False, the default, returns the number of samples in each bin.
+ If True, returns the probability *density* function at the bin,
+ ``bin_count / sample_count / bin_area``.
normed : bool, optional
- If False, returns the number of samples in each bin. If True,
- returns the bin density ``bin_count / sample_count / bin_area``.
+ An alias for the density argument that behaves identically. To avoid
+ confusion with the broken normed argument to `histogram`, `density`
+ should be preferred.
weights : array_like, shape(N,), optional
An array of values ``w_i`` weighing each sample ``(x_i, y_i)``.
Weights are normalized to 1 if `normed` is True. If `normed` is
@@ -652,7 +658,7 @@ def histogram2d(x, y, bins=10, range=None, normed=False, weights=None):
if N != 1 and N != 2:
xedges = yedges = asarray(bins)
bins = [xedges, yedges]
- hist, edges = histogramdd([x, y], bins, range, normed, weights)
+ hist, edges = histogramdd([x, y], bins, range, normed, weights, density)
return hist, edges[0], edges[1]