docs: add code snippets for explore query result page (#278)

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Fixes internal issue 316614454 🦕

samples/snippets/explore_query_result_test.py

@@ -0,0 +1,70 @@
+# Copyright 2023 Google LLC
+#
+# Licensed under the Apache License, Version 2.0 (the "License");
+# you may not use this file except in compliance with the License.
+# You may obtain a copy of the License at
+#
+#     http://www.apache.org/licenses/LICENSE-2.0
+#
+# Unless required by applicable law or agreed to in writing, software
+# distributed under the License is distributed on an "AS IS" BASIS,
+# WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
+# See the License for the specific language governing permissions and
+# limitations under the License.
+
+
+def test_bigquery_dataframes_explore_query_result():
+    import bigframes.pandas as bpd
+
+    # [START bigquery_dataframes_explore_query_result]
+    # Load data from BigQuery
+    query_or_table = "bigquery-public-data.ml_datasets.penguins"
+    bq_df = bpd.read_gbq(query_or_table)
+
+    # Inspect one of the columns (or series) of the DataFrame:
+    bq_df["body_mass_g"]
+
+    # Compute the mean of this series:
+    average_body_mass = bq_df["body_mass_g"].mean()
+    print(f"average_body_mass: {average_body_mass}")
+
+    # Find the heaviest species using the groupby operation to calculate the
+    # mean body_mass_g:
+    (
+        bq_df["body_mass_g"]
+        .groupby(by=bq_df["species"])
+        .mean()
+        .sort_values(ascending=False)
+        .head(10)
+    )
+
+    # Create the Linear Regression model
+    from bigframes.ml.linear_model import LinearRegression
+
+    # Filter down to the data we want to analyze
+    adelie_data = bq_df[bq_df.species == "Adelie Penguin (Pygoscelis adeliae)"]
+
+    # Drop the columns we don't care about
+    adelie_data = adelie_data.drop(columns=["species"])
+
+    # Drop rows with nulls to get our training data
+    training_data = adelie_data.dropna()
+
+    # Pick feature columns and label column
+    X = training_data[
+        [
+            "island",
+            "culmen_length_mm",
+            "culmen_depth_mm",
+            "flipper_length_mm",
+            "sex",
+        ]
+    ]
+    y = training_data[["body_mass_g"]]
+
+    model = LinearRegression(fit_intercept=False)
+    model.fit(X, y)
+    model.score(X, y)
+    # [END bigquery_dataframes_explore_query_result]
+    assert average_body_mass is not None
+    assert model is not None