diff --git a/src/calculator.py b/src/calculator.py index 12f9426..8448428 100644 --- a/src/calculator.py +++ b/src/calculator.py @@ -31,11 +31,15 @@ def average(values: list[int | float]) -> float: return sum(values) / len(values) -def variance(values: Sequence[float]) -> float: +def median(values: list[float]) -> float: if not values: raise ValueError - mean = sum(values) / len(values) - return sum((x - mean) ** 2 for x in values) / len(values) + sorted_values = sorted(values) + n = len(sorted_values) + mid = n // 2 + if n % 2 == 1: + return sorted_values[mid] + return (sorted_values[mid - 1] + sorted_values[mid]) / 2.0 def percentage(value: Union[int, float], total: Union[int, float]) -> float: @@ -43,3 +47,10 @@ def percentage(value: Union[int, float], total: Union[int, float]) -> float: raise ValueError return (value / total) * 100 + +def variance(values: Sequence[float]) -> float: + if not values: + raise ValueError + mean = sum(values) / len(values) + return sum((x - mean) ** 2 for x in values) / len(values) + diff --git a/src/typosaurus_sandbox/domain/calculator/__init__.py b/src/typosaurus_sandbox/domain/calculator/__init__.py index e4dd0d5..087f1b5 100644 --- a/src/typosaurus_sandbox/domain/calculator/__init__.py +++ b/src/typosaurus_sandbox/domain/calculator/__init__.py @@ -1,7 +1,6 @@ # retoor -from typosaurus_sandbox.domain.calculator.operations import add, average, clamp, clamp_to_byte, percentage, subtract, variance - -__all__ = ["add", "average", "clamp", "clamp_to_byte", "percentage", "subtract", "variance"] +from typosaurus_sandbox.domain.calculator.operations import add, average, clamp, clamp_to_byte, median, percentage, subtract, variance +__all__ = ["add", "average", "clamp", "clamp_to_byte", "median", "percentage", "subtract", "variance"] diff --git a/src/typosaurus_sandbox/domain/calculator/operations.py b/src/typosaurus_sandbox/domain/calculator/operations.py index 12f9426..3a93935 100644 --- a/src/typosaurus_sandbox/domain/calculator/operations.py +++ b/src/typosaurus_sandbox/domain/calculator/operations.py @@ -31,6 +31,17 @@ def average(values: list[int | float]) -> float: return sum(values) / len(values) +def median(values: list[float]) -> float: + if not values: + raise ValueError + sorted_values = sorted(values) + n = len(sorted_values) + mid = n // 2 + if n % 2 == 1: + return sorted_values[mid] + return (sorted_values[mid - 1] + sorted_values[mid]) / 2.0 + + def variance(values: Sequence[float]) -> float: if not values: raise ValueError diff --git a/tests/test_calculator.py b/tests/test_calculator.py index a7d33b7..d90f99d 100644 --- a/tests/test_calculator.py +++ b/tests/test_calculator.py @@ -3,7 +3,7 @@ import math import unittest -from typosaurus_sandbox.domain.calculator import add, average, clamp, clamp_to_byte, subtract, variance +from typosaurus_sandbox.domain.calculator import add, average, clamp, clamp_to_byte, median, subtract, variance class TestAddFunction(unittest.TestCase): @@ -125,6 +125,32 @@ class TestClampFunction(unittest.TestCase): self.assertTrue(math.isnan(result)) +class TestMedianFunction(unittest.TestCase): + + def test_odd_length_returns_middle_element(self) -> None: + self.assertEqual(median([1, 3, 5]), 3) + + def test_even_length_returns_float_average_of_two_middle_values(self) -> None: + result = median([1, 2, 3, 4]) + self.assertIsInstance(result, float) + self.assertEqual(result, 2.5) + + def test_single_element_returns_that_element(self) -> None: + self.assertEqual(median([7]), 7) + + def test_empty_list_raises_value_error(self) -> None: + with self.assertRaises(ValueError): + median([]) + + def test_unsorted_input_sorts_correctly(self) -> None: + self.assertEqual(median([3, 1, 2]), 2) + + def test_unsorted_even_length_returns_float_average(self) -> None: + result = median([10, 30, 20, 40]) + self.assertIsInstance(result, float) + self.assertEqual(result, 25.0) + + class TestVarianceFunction(unittest.TestCase): def test_empty_list_raises_value_error(self) -> None: