Merged in sergem/numpy/digitize2 (pull request ganesh-k13#14)

mattip · mattip · commit 15bcd04a5208 · 2016-03-13T20:48:10.000+02:00
Digitize2
diff --git a/numpy/core/multiarray.py b/numpy/core/multiarray.py
@@ -1,6 +1,6 @@
 from _numpypy.multiarray import *
 from _numpypy.multiarray import _reconstruct
-from pypy_impl import bincount
+from pypy_impl import bincount, digitize
 
 def _fastCopyAndTranspose(a):
     return a.T.copy()
@@ -100,7 +100,7 @@ def __init__(self, *args, **kwargs):
 for name in '''
 nested_iters
 broadcast empty_like fromiter fromfile frombuffer newbuffer getbuffer
-int_asbuffer set_numeric_ops promote_types digitize
+int_asbuffer set_numeric_ops promote_types
 lexsort compare_chararrays putmask einsum inner interp
 _vec_string datetime_data correlate correlate2 vdot matmul _insert
 datetime_as_string busday_offset busday_count is_busday busdaycalendar
diff --git a/numpy/core/pypy_impl/__init__.py b/numpy/core/pypy_impl/__init__.py
@@ -1 +1,2 @@
+from digitize import digitize
 from bincount import bincount
diff --git a/numpy/core/pypy_impl/digitize.py b/numpy/core/pypy_impl/digitize.py
@@ -0,0 +1,83 @@
+from numpy.core.multiarray import dtype
+from numpy.core.multiarray import array
+
+
+def digitize(x, bins, right=False):
+
+    x = array(x, dtype=dtype('float'))
+    bins = array(bins, dtype=dtype('float'))
+
+    if len(bins) == 0:
+        raise ValueError("bins must have non-zero length")
+
+    monotonic = check_monotonic(bins)
+    if monotonic == 0:
+        raise ValueError("bins must be monotonically increasing or decreasing")
+
+    if monotonic == -1:
+        bins = bins[::-1]
+    result = bins.searchsorted(x, side='right' if not right else 'left')
+    if monotonic == -1:
+        result = len(bins) - result
+
+    return result
+
+
+def check_monotonic(a):
+    """
+
+    Parameters
+    ----------
+    a
+        input array
+
+    Returns
+        -1 -- for monotonic, non-increasing
+        0  -- for non-monotonic
+        1  -- for monotonic, non-decreasing
+    -------
+
+    >>> check_monotonic([1,2,3])
+    1
+    >>> check_monotonic([3,2,1])
+    -1
+    >>> check_monotonic([3,1,2])
+    0
+    >>> check_monotonic([1, 1, 1, 3, 100])
+    1
+    >>> check_monotonic([1, 1, 1, 0, -1])
+    -1
+    >>> check_monotonic([1, 1, 1, 3, 2])
+    0
+    >>> check_monotonic([1123123])
+    1
+    """
+    len_a = len(a)
+    assert len_a > 0
+
+    last = a[0]
+    i = 1
+    while i < len_a and a[0] == a[i]:
+        i += 1
+
+    if i == len_a:
+        return 1
+
+    next = a[i]
+    i += 1
+    if last < next:
+        while i < len_a:
+            last = next
+            next = a[i]
+            if last > next:
+                return 0
+            i += 1
+        return 1
+    else:
+        while i < len_a:
+            last = next
+            next = a[i]
+            if last < next:
+                return 0
+            i += 1
+        return -1

Original file line number	Diff line number	Diff line change
`@@ -1 +1,2 @@`
	`1`	`+from digitize import digitize`
`1`	`2`	`from bincount import bincount`