diff --git a/doc/source/whatsnew/v0.24.0.txt b/doc/source/whatsnew/v0.24.0.txt
index 9b70bda82e247..75c2a8acdc859 100644
--- a/doc/source/whatsnew/v0.24.0.txt
+++ b/doc/source/whatsnew/v0.24.0.txt
@@ -600,7 +600,7 @@ Interval
- Bug in the :class:`IntervalIndex` constructor where the ``closed`` parameter did not always override the inferred ``closed`` (:issue:`19370`)
- Bug in the ``IntervalIndex`` repr where a trailing comma was missing after the list of intervals (:issue:`20611`)
--
+- Bug in :class:`Interval` where scalar arithmetic operations did not retain the ``closed`` value (:issue:`22313`)
-
Indexing
diff --git a/pandas/_libs/interval.pyx b/pandas/_libs/interval.pyx
index 22153b58cc49b..5ae20a27c2381 100644
--- a/pandas/_libs/interval.pyx
+++ b/pandas/_libs/interval.pyx
@@ -326,36 +326,37 @@ cdef class Interval(IntervalMixin):
def __add__(self, y):
if isinstance(y, numbers.Number):
- return Interval(self.left + y, self.right + y)
+ return Interval(self.left + y, self.right + y, closed=self.closed)
elif isinstance(y, Interval) and isinstance(self, numbers.Number):
- return Interval(y.left + self, y.right + self)
+ return Interval(y.left + self, y.right + self, closed=y.closed)
return NotImplemented
def __sub__(self, y):
if isinstance(y, numbers.Number):
- return Interval(self.left - y, self.right - y)
+ return Interval(self.left - y, self.right - y, closed=self.closed)
return NotImplemented
def __mul__(self, y):
if isinstance(y, numbers.Number):
- return Interval(self.left * y, self.right * y)
+ return Interval(self.left * y, self.right * y, closed=self.closed)
elif isinstance(y, Interval) and isinstance(self, numbers.Number):
- return Interval(y.left * self, y.right * self)
+ return Interval(y.left * self, y.right * self, closed=y.closed)
return NotImplemented
def __div__(self, y):
if isinstance(y, numbers.Number):
- return Interval(self.left / y, self.right / y)
+ return Interval(self.left / y, self.right / y, closed=self.closed)
return NotImplemented
def __truediv__(self, y):
if isinstance(y, numbers.Number):
- return Interval(self.left / y, self.right / y)
+ return Interval(self.left / y, self.right / y, closed=self.closed)
return NotImplemented
def __floordiv__(self, y):
if isinstance(y, numbers.Number):
- return Interval(self.left // y, self.right // y)
+ return Interval(
+ self.left // y, self.right // y, closed=self.closed)
return NotImplemented
diff --git a/pandas/tests/scalar/interval/test_interval.py b/pandas/tests/scalar/interval/test_interval.py
index c9e6e84d226a8..8d17989ebc7b1 100644
--- a/pandas/tests/scalar/interval/test_interval.py
+++ b/pandas/tests/scalar/interval/test_interval.py
@@ -109,79 +109,103 @@ def test_length_errors(self, left, right):
with tm.assert_raises_regex(TypeError, msg):
iv.length
- def test_math_add(self, interval):
- expected = Interval(1, 2)
- actual = interval + 1
- assert expected == actual
+ def test_math_add(self, closed):
+ interval = Interval(0, 1, closed=closed)
+ expected = Interval(1, 2, closed=closed)
- expected = Interval(1, 2)
- actual = 1 + interval
- assert expected == actual
+ result = interval + 1
+ assert result == expected
+
+ result = 1 + interval
+ assert result == expected
- actual = interval
- actual += 1
- assert expected == actual
+ result = interval
+ result += 1
+ assert result == expected
msg = r"unsupported operand type\(s\) for \+"
with tm.assert_raises_regex(TypeError, msg):
- interval + Interval(1, 2)
+ interval + interval
with tm.assert_raises_regex(TypeError, msg):
interval + 'foo'
- def test_math_sub(self, interval):
- expected = Interval(-1, 0)
- actual = interval - 1
- assert expected == actual
+ def test_math_sub(self, closed):
+ interval = Interval(0, 1, closed=closed)
+ expected = Interval(-1, 0, closed=closed)
+
+ result = interval - 1
+ assert result == expected
- actual = interval
- actual -= 1
- assert expected == actual
+ result = interval
+ result -= 1
+ assert result == expected
msg = r"unsupported operand type\(s\) for -"
with tm.assert_raises_regex(TypeError, msg):
- interval - Interval(1, 2)
+ interval - interval
with tm.assert_raises_regex(TypeError, msg):
interval - 'foo'
- def test_math_mult(self, interval):
- expected = Interval(0, 2)
- actual = interval * 2
- assert expected == actual
+ def test_math_mult(self, closed):
+ interval = Interval(0, 1, closed=closed)
+ expected = Interval(0, 2, closed=closed)
+
+ result = interval * 2
+ assert result == expected
- expected = Interval(0, 2)
- actual = 2 * interval
- assert expected == actual
+ result = 2 * interval
+ assert result == expected
- actual = interval
- actual *= 2
- assert expected == actual
+ result = interval
+ result *= 2
+ assert result == expected
msg = r"unsupported operand type\(s\) for \*"
with tm.assert_raises_regex(TypeError, msg):
- interval * Interval(1, 2)
+ interval * interval
msg = r"can\'t multiply sequence by non-int"
with tm.assert_raises_regex(TypeError, msg):
interval * 'foo'
- def test_math_div(self, interval):
- expected = Interval(0, 0.5)
- actual = interval / 2.0
- assert expected == actual
+ def test_math_div(self, closed):
+ interval = Interval(0, 1, closed=closed)
+ expected = Interval(0, 0.5, closed=closed)
- actual = interval
- actual /= 2.0
- assert expected == actual
+ result = interval / 2.0
+ assert result == expected
+
+ result = interval
+ result /= 2.0
+ assert result == expected
msg = r"unsupported operand type\(s\) for /"
with tm.assert_raises_regex(TypeError, msg):
- interval / Interval(1, 2)
+ interval / interval
with tm.assert_raises_regex(TypeError, msg):
interval / 'foo'
+ def test_math_floordiv(self, closed):
+ interval = Interval(1, 2, closed=closed)
+ expected = Interval(0, 1, closed=closed)
+
+ result = interval // 2
+ assert result == expected
+
+ result = interval
+ result //= 2
+ assert result == expected
+
+ msg = r"unsupported operand type\(s\) for //"
+ with tm.assert_raises_regex(TypeError, msg):
+ interval // interval
+
+ with tm.assert_raises_regex(TypeError, msg):
+ interval // 'foo'
+
def test_constructor_errors(self):
msg = "invalid option for 'closed': foo"
with tm.assert_raises_regex(ValueError, msg):