Repository: great-expectations/great_expectations

Issue:
Use cleaner solution for non-truncating division in python 2
Prefer `from __future__ import division` to `1.*x/y`


Discussion:
Done inline during improve_partitions push.

Resolving patch:
diff --git a/contrib/experimental/great_expectations_experimental/expectations/expect_multicolumn_values_not_to_be_all_null.py b/contrib/experimental/great_expectations_experimental/expectations/expect_multicolumn_values_not_to_be_all_null.py
new file mode 100644
--- /dev/null
+++ b/contrib/experimental/great_expectations_experimental/expectations/expect_multicolumn_values_not_to_be_all_null.py
@@ -0,0 +1,163 @@
+from typing import Optional
+
+import numpy as np
+
+from great_expectations.core.expectation_configuration import ExpectationConfiguration
+from great_expectations.execution_engine import PandasExecutionEngine
+from great_expectations.expectations.expectation import MulticolumnMapExpectation
+from great_expectations.expectations.metrics.map_metric_provider import (
+    MulticolumnMapMetricProvider,
+    multicolumn_condition_partial,
+)
+
+
+# This class defines a Metric to support your Expectation.
+# For most MulticolumnMapExpectations, the main business logic for calculation will live in this class.
+class MulticolumnValuesNotAllNull(MulticolumnMapMetricProvider):
+
+    # This is the id string that will be used to reference your metric.
+
+    condition_metric_name = "multicolumn_values.not_all_null"
+
+    # These point your metric at the provided keys to facilitate calculation
+    condition_domain_keys = (
+        "batch_id",
+        "table",
+        "column_list",
+        "row_condition",
+        "condition_parser",
+        "ignore_row_if",
+    )
+    condition_value_keys = ()
+
+    # This method implements the core logic for the PandasExecutionEngine
+
+    @multicolumn_condition_partial(engine=PandasExecutionEngine)
+    def _pandas(cls, column_list, **kwargs):
+        row_wise_cond = column_list.isna().sum(axis=1) < len(column_list)
+        return row_wise_cond
+
+    # This method defines the business logic for evaluating your metric when using a SqlAlchemyExecutionEngine
+    # @multicolumn_condition_partial(engine=SqlAlchemyExecutionEngine)
+    # def _sqlalchemy(cls, column_list, **kwargs):
+    #     raise NotImplementedError
+
+    # This method defines the business logic for evaluating your metric when using a SparkDFExecutionEngine
+    # @multicolumn_condition_partial(engine=SparkDFExecutionEngine)
+    # def _spark(cls, column_list, **kwargs):
+    #     raise NotImplementedError
+
+
+# This class defines the Expectation itself
+class ExpectMulticolumnValuesNotToBeAllNull(MulticolumnMapExpectation):
+    """Expect the certain set of columns not to be null at the same time."""
+
+    # These examples will be shown in the public gallery.
+    # They will also be executed as unit tests for your Expectation.
+    examples = [
+        {
+            "data": {
+                "no_nulls": [5, 6, 5, 12, -3],
+                "some_nulls": [np.nan, -3, np.nan, np.nan, -9],
+                "one_non_null": [np.nan, 2, np.nan, np.nan, np.nan],
+                "all_nulls": [np.nan, np.nan, np.nan, np.nan, np.nan],
+            },
+            "tests": [
+                {
+                    "title": "basic_positive_test",
+                    "exact_match_out": False,
+                    "include_in_gallery": True,
+                    "in": {"column_list": ["no_nulls", "some_nulls"]},
+                    "out": {
+                        "success": True,
+                    },
+                },
+                {
+                    "title": "basic_positive_test",
+                    "exact_match_out": False,
+                    "include_in_gallery": True,
+                    "in": {
+                        "column_list": ["some_nulls", "one_non_null"],
+                        "mostly": 0.4,
+                    },
+                    "out": {
+                        "success": True,
+                    },
+                },
+                {
+                    "title": "basic_negative_test",
+                    "exact_match_out": False,
+                    "include_in_gallery": True,
+                    "in": {
+                        "column_list": ["some_nulls", "one_non_null", "all_nulls"],
+                        "mostly": 1,
+                    },
+                    "out": {
+                        "success": False,
+                    },
+                },
+            ],
+            "test_backends": [
+                {
+                    "backend": "pandas",
+                    "dialects": None,
+                },
+            ],
+        }
+    ]
+
+    # This is the id string of the Metric used by this Expectation.
+    # For most Expectations, it will be the same as the `condition_metric_name` defined in your Metric class above.
+
+    map_metric = "multicolumn_values.not_all_null"
+
+    # This is a list of parameter names that can affect whether the Expectation evaluates to True or False
+    success_keys = (
+        "column_list",
+        "mostly",
+    )
+
+    # This dictionary contains default values for any parameters that should have default values
+    default_kwarg_values = {}
+
+    def validate_configuration(
+        self, configuration: Optional[ExpectationConfiguration] = None
+    ) -> None:
+        """
+        Validates that a configuration has been set, and sets a configuration if it has yet to be set. Ensures that
+        necessary configuration arguments have been provided for the validation of the expectation.
+
+        Args:
+            configuration (OPTIONAL[ExpectationConfiguration]): \
+                An optional Expectation Configuration entry that will be used to configure the expectation
+        Returns:
+            None. Raises InvalidExpectationConfigurationError if the config is not validated successfully
+        """
+
+        super().validate_configuration(configuration)
+        configuration = configuration or self.configuration
+
+        # # Check other things in configuration.kwargs and raise Exceptions if needed
+        # try:
+        #     assert (
+        #         ...
+        #     ), "message"
+        #     assert (
+        #         ...
+        #     ), "message"
+        # except AssertionError as e:
+        #     raise InvalidExpectationConfigurationError(str(e))
+
+    # This object contains metadata for display in the public Gallery
+
+    library_metadata = {
+        "tags": ["null_check"],  # Tags for this Expectation in the Gallery
+        "contributors": [  # Github handles for all contributors to this Expectation.
+            "@liyusa",  # Don't forget to add your github handle here!
+        ],
+    }
+
+
+if __name__ == "__main__":
+
+    ExpectMulticolumnValuesNotToBeAllNull().print_diagnostic_checklist()


Test patch: