feat(pandas): add problem 1075

Author: IndexSeek

README.md

@@ -32,7 +32,7 @@ Fiddling around with DataFusion, pandas, and PyArrow.
 |----------:|:------|:-----------|:----------:|:------:|:-------:|
 | 620  | [Not Boring Movies](https://leetcode.com/problems/not-boring-movies) | Easy | ✅ | ✅ | ✅ |
 | 1251 | [Average Selling Price](https://leetcode.com/problems/average-selling-price) | Easy | ❌ | ✅ | ✅ |
-| 1075 | [Project Employees I](https://leetcode.com/problems/project-employees-i) | Easy | ❌ | ❌ | ✅ |
+| 1075 | [Project Employees I](https://leetcode.com/problems/project-employees-i) | Easy | ❌ | ✅ | ✅ |
 | 1633 | [Percentage of Users Attended a Contest](https://leetcode.com/problems/percentage-of-users-attended-a-contest) | Easy | ❌ | ❌ | ✅ |
 | 1211 | [Queries Quality and Percentage](https://leetcode.com/problems/queries-quality-and-percentage) | Easy | ❌ | ❌ | ✅ |
 | 1193 | [Monthly Transactions I](https://leetcode.com/problems/monthly-transactions-i) | Medium | ✅ | ❌ | ❌ |

problems/pandas.py

@@ -201,6 +201,33 @@ def problem_1068(sales: pd.DataFrame, product: pd.DataFrame) -> pd.DataFrame:
     return sales.merge(product, on="product_id")[["product_name", "year", "price"]]
 
 
+def problem_1075(project: pd.DataFrame, employee: pd.DataFrame) -> pd.DataFrame:
+    """Report each project's average employee experience, rounded to 2 digits.
+
+    Return the result table in any order.
+
+    Parameters
+    ----------
+    project : pd.DataFrame
+        Table shows employees (employee_id) working on projects (project_id).
+    employee : pd.DataFrame
+        This table contains information about one employee.
+
+    Returns
+    -------
+    pd.DataFrame
+
+    """
+    joined = (
+        project.merge(employee)
+        .groupby("project_id")
+        .aggregate(average_years=pd.NamedAgg(column="experience_years", aggfunc="mean"))
+        .reset_index()
+    )
+    joined["average_years"] = joined["average_years"].round(2)
+    return joined
+
+
 def problem_1148(views: pd.DataFrame) -> pd.DataFrame:
     """Find all the authors that viewed at least one of their own articles.
 

problems/pyarrow.py

@@ -673,7 +673,7 @@ def problem_1075(project: pa.Table, employee: pa.Table) -> pa.Table:
         .aggregate([("experience_years", "mean")])
     )
     return joined.set_column(
-        1, "experience_years", pc.round(joined["experience_years_mean"], 2)
+        1, "average_years", pc.round(joined["experience_years_mean"], 2)
     )
 
 

tests/test_pandas.py

@@ -14,6 +14,7 @@
     problem_595,
     problem_620,
     problem_1068,
+    problem_1075,
     problem_1148,
     problem_1251,
     problem_1280,
@@ -437,6 +438,41 @@ def test_problem_1068(input_data_1, input_data_2, expected_data):
     )
 
 
+@pytest.mark.parametrize(
+    "input_data_1, input_data_2, expected_data",
+    [
+        pytest.param(
+            {
+                "employee_id": [1, 2, 3],
+                "project_id": [101, 102, 103],
+                "experience_years": [5, 10, 15],
+            },
+            {"employee_id": [1, 2, 3], "department": ["HR", "IT", "Finance"]},
+            {"project_id": [101, 102, 103], "average_years": [5.0, 10.0, 15.0]},
+            id="happy_path",
+        ),
+        pytest.param(
+            {
+                "employee_id": [1, 2, 3],
+                "project_id": [101, 101, 101],
+                "experience_years": [33, 34, 34],
+            },
+            {"employee_id": [1, 2, 3], "department": ["HR", "IT", "IT"]},
+            {"project_id": [101], "average_years": [33.67]},
+            id="happy_path_rounding_2",
+        ),
+    ],
+)
+def test_problem_1075(input_data_1, input_data_2, expected_data):
+    table_1 = pd.DataFrame(input_data_1)
+    table_2 = pd.DataFrame(input_data_2)
+    expected_table = pd.DataFrame(expected_data)
+    result = problem_1075(table_1, table_2).reset_index(drop=True)
+    assert_frame_equal(
+        result, expected_table, check_dtype=False, check_index_type=False
+    )
+
+
 @pytest.mark.parametrize(
     "input_data, expected_data",
     [

tests/test_pyarrow.py

@@ -1101,7 +1101,7 @@ def test_problem_1070(input_data, expected_data):
                 "experience_years": [5, 10, 15],
             },
             {"employee_id": [1, 2, 3], "department": ["HR", "IT", "Finance"]},
-            {"project_id": [101, 102, 103], "experience_years": [5.0, 10.0, 15.0]},
+            {"project_id": [101, 102, 103], "average_years": [5.0, 10.0, 15.0]},
             id="happy_path",
         ),
         pytest.param(
@@ -1111,7 +1111,7 @@ def test_problem_1070(input_data, expected_data):
                 "experience_years": [33, 34, 34],
             },
             {"employee_id": [1, 2, 3], "department": ["HR", "IT", "IT"]},
-            {"project_id": [101], "experience_years": [33.67]},
+            {"project_id": [101], "average_years": [33.67]},
             id="happy_path_rounding_2",
         ),
     ],