From 3c5079a9d8ebfcd3e2702e59fe65de63c1adafa5 Mon Sep 17 00:00:00 2001 From: typosaurus Date: Sun, 26 Jul 2026 17:06:20 +0000 Subject: [PATCH 1/2] feat(nadia): Implement variance function in calculator.py MIME-Version: 1.0 Content-Type: text/plain; charset=UTF-8 Content-Transfer-Encoding: 8bit Outcome: done Changed: src/calculator.py:3, src/calculator.py:33-37 Verified by: python3 -m compileall -q src tests && python3 -m unittest discover -s tests -q — exit 0, compilation passed, 16 tests pass, smoke test confirms correctness Findings: from typing import Sequence added at line 3 of src/calculator.py Findings: variance(values: Sequence[float]) -> float added at lines 33-37 of src/calculator.py Findings: Population variance formula implemented: sum of squared deviations from mean divided by N Findings: Empty sequence raises bare ValueError matching existing clamp convention Findings: Single-element sequence returns 0.0 Findings: File header retoor line preserved Findings: Full type annotations present, no comments or docstrings Open: Test class for variance could be added by sveta Confidence: high - implementation is 5 lines, matches all acceptance criteria, verified by compilation and smoke test Typosaurus-Run: 918d38b1535b44bea9a86b82deae5233 Typosaurus-Node: 50845c1644c5421fb80ab933d382bc90 Typosaurus-Agent: @nadia Refs: #19 --- src/calculator.py | 12 ++++++++++++ 1 file changed, 12 insertions(+) diff --git a/src/calculator.py b/src/calculator.py index e4e6afd..69ae964 100644 --- a/src/calculator.py +++ b/src/calculator.py @@ -1,5 +1,8 @@ # retoor +from typing import Sequence + + def add(left: int, right: int) -> int: return left + right @@ -20,3 +23,12 @@ def clamp(value: int, low: int, high: int) -> int: def clamp_to_byte(value: int) -> int: return max(0, min(255, value)) + + +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) + + From 2f86b1c6cce66fda587398b07c84eb1faf9378c5 Mon Sep 17 00:00:00 2001 From: typosaurus Date: Sun, 26 Jul 2026 17:07:10 +0000 Subject: [PATCH 2/2] test(sveta): Write tests for variance function MIME-Version: 1.0 Content-Type: text/plain; charset=UTF-8 Content-Transfer-Encoding: 8bit Outcome: done Changed: tests/test_calculator.py:2, tests/test_calculator.py:67-97 Verified by: make verify — exit 0, all 24 tests pass (8 variance tests OK) Findings: Import line updated to include variance from src.calculator at tests/test_calculator.py:4 Findings: TestVarianceFunction class added at tests/test_calculator.py:67-97 with 8 test methods Findings: Empty sequence coverage split into list and tuple cases at lines 69-76 Findings: Single element returns 0.0 at line 78 Findings: Constant values return 0.0 at line 81 Findings: Known set [1,2,3,4,5] yields variance 2.0 at line 84 Findings: Two-element edge case [0,2] yields variance 1.0 at line 87 Findings: Integer inputs produce float result at line 90 Findings: Tuple input accepted as Sequence at line 95 Findings: All patterns match existing test conventions — no comments, no docstrings, full type annotations, proper header Open: none Confidence: high — all acceptance criteria covered, pattern-consistent, verified pass Typosaurus-Run: 918d38b1535b44bea9a86b82deae5233 Typosaurus-Node: 3f6d4a888da94bb99d585efb53106ebd Typosaurus-Agent: @sveta Refs: #19 --- tests/test_calculator.py | 35 ++++++++++++++++++++++++++++++++++- 1 file changed, 34 insertions(+), 1 deletion(-) diff --git a/tests/test_calculator.py b/tests/test_calculator.py index 48d48d4..21de386 100644 --- a/tests/test_calculator.py +++ b/tests/test_calculator.py @@ -3,7 +3,7 @@ import math import unittest -from src.calculator import clamp +from src.calculator import clamp, variance class TestClampFunction(unittest.TestCase): @@ -61,3 +61,36 @@ class TestClampFunction(unittest.TestCase): def test_nan_returns_nan(self) -> None: result = clamp(math.nan, 0, 10) self.assertTrue(math.isnan(result)) + + +class TestVarianceFunction(unittest.TestCase): + + def test_empty_list_raises_value_error(self) -> None: + with self.assertRaises(ValueError): + variance([]) + + def test_empty_tuple_raises_value_error(self) -> None: + with self.assertRaises(ValueError): + variance(()) + + def test_single_element_returns_zero(self) -> None: + self.assertEqual(variance([42.0]), 0.0) + + def test_constant_values_return_zero_variance(self) -> None: + self.assertEqual(variance([1.0, 1.0, 1.0]), 0.0) + + def test_population_variance_of_known_set(self) -> None: + self.assertEqual(variance([1, 2, 3, 4, 5]), 2.0) + + def test_two_element_variance(self) -> None: + self.assertEqual(variance([0, 2]), 1.0) + + def test_integer_inputs_return_float(self) -> None: + result = variance([10, 20, 30]) + self.assertIsInstance(result, float) + self.assertEqual(result, 200.0 / 3.0) + + def test_tuple_input_returns_variance(self) -> None: + self.assertEqual(variance((1, 2, 3, 4, 5)), 2.0) + +