in memory PoC

distribution/lib/Standard/Table/0.0.0-dev/src/Internal/Type_Refinements/Column_Refinements.enso

@@ -4,35 +4,46 @@ from Standard.Base import all
 
 import project.Column.Column
 import project.Internal.Value_Type_Helpers
+import project.Refined_Types.Numeric_Column.Numeric_Column
 import project.Value_Type.Value_Type
 from project.Internal.Type_Refinements.Single_Value_Column_Conversions import all
 from project.Internal.Type_Refinements.Typed_Column_Conversions import all
 
 refine_column (column : Column) =
     ## We treat a column as single value if it contains a single not-nothing value.
-    if is_single_value column . not then column else
-        inferred_value_type = column.inferred_precise_value_type
-        case inferred_value_type of
-            Value_Type.Integer _ ->
-                # `inferred_precise_value_type` will return Integer if the column was Float (or Mixed) but contained integral values - e.g. [2.0]
-                # We inspect the actual value to correctly deal with both Float and Mixed base type.
-                value = column.at 0
-                case value of
-                    # If the value was really a float, we preserve that.
-                    _ : Float -> (column : Column & Numeric_Column & Float)
-                    # Otherwise we treat it as an integer.
-                    _ -> (column : Column & Numeric_Column & Integer)
-            Value_Type.Float _ -> (column : Column & Numeric_Column & Float)
-            Value_Type.Char _ _ -> (column : Column & Text)
-            Value_Type.Boolean -> (column : Column & Boolean)
-            Value_Type.Date -> (column : Column & Date)
-            Value_Type.Time -> (column : Column & Time_Of_Day)
-            Value_Type.Date_Time True -> (column : Column & Date_Time)
-            Value_Type.Decimal _ _ ->
-                is_integer = Value_Type_Helpers.is_decimal_integer inferred_value_type
-                if is_integer then (column : Column & Numeric_Column & Integer) else (column : Column & Numeric_Column & Decimal)
-            # Other types (e.g. Mixed) are not supported.
-            _ -> column
+    if is_single_value column then _refine_single_value_column column else _refine_column column
+
+private _refine_column column =
+    inferred_value_type = column.inferred_precise_value_type
+    case inferred_value_type of
+        Value_Type.Integer _ -> (column : Column & Numeric_Column)
+        Value_Type.Float _ -> (column : Column & Numeric_Column)
+        Value_Type.Decimal _ _ -> (column : Column & Numeric_Column)
+        _ -> column
+
+private _refine_single_value_column column =
+    inferred_value_type = column.inferred_precise_value_type
+    case inferred_value_type of
+        Value_Type.Integer _ ->
+            # `inferred_precise_value_type` will return Integer if the column was Float (or Mixed) but contained integral values - e.g. [2.0]
+            # We inspect the actual value to correctly deal with both Float and Mixed base type.
+            value = column.at 0
+            case value of
+                # If the value was really a float, we preserve that.
+                _ : Float -> (column : Column & Numeric_Column & Float)
+                # Otherwise we treat it as an integer.
+                _ -> (column : Column & Numeric_Column & Integer)
+        Value_Type.Float _ -> (column : Column & Numeric_Column & Float)
+        Value_Type.Char _ _ -> (column : Column & Text)
+        Value_Type.Boolean -> (column : Column & Boolean)
+        Value_Type.Date -> (column : Column & Date)
+        Value_Type.Time -> (column : Column & Time_Of_Day)
+        Value_Type.Date_Time True -> (column : Column & Date_Time)
+        Value_Type.Decimal _ _ ->
+            is_integer = Value_Type_Helpers.is_decimal_integer inferred_value_type
+            if is_integer then (column : Column & Numeric_Column & Integer) else (column : Column & Numeric_Column & Decimal)
+        # Other types (e.g. Mixed) are not supported.
+        _ -> column
 
 is_single_value column:Column -> Boolean =
     (column.length == 1) && (column.at 0 . is_nothing . not)

distribution/lib/Standard/Table/0.0.0-dev/src/Internal/Type_Refinements/Table_Refinements.enso

@@ -4,6 +4,7 @@ from Standard.Base import all
 
 import project.Column.Column
 import project.Internal.Value_Type_Helpers
+import project.Refined_Types.Numeric_Column.Numeric_Column
 import project.Table.Table
 import project.Value_Type.Value_Type
 from project.Internal.Type_Refinements.Single_Column_Table_Conversions import all

distribution/lib/Standard/Table/0.0.0-dev/src/Internal/Type_Refinements/Typed_Column_Conversions.enso

@@ -1,5 +1,30 @@
 private
 
+from Standard.Base import all
+import Standard.Base.Errors.Illegal_Argument.Illegal_Argument
+
+import project.Column.Column
+import project.Internal.Type_Refinements.Typed_Column_Helpers
+import project.Refined_Types.Numeric_Column.Numeric_Column
+import project.Value_Type.Value_Type
+from project.Column import apply_unary_operation, naming_helper
+
+polyglot java import org.enso.table.data.column.operation.unary.AbsOperation
+polyglot java import org.enso.table.data.column.operation.unary.SignumOperation
+
 ## This conversion is internal and should never be exported.
 Numeric_Column.from (that : Column) =
-    ...
+    if that.value_type.is_numeric.not then
+        Error.throw (Illegal_Argument.Error "Cannot convert a "+that.value_type.to_display_text+" column to a numeric column.")
+    Typed_Column_Helpers.make_numeric_column that In_Memory_Numeric_Column_Implementation
+
+type In_Memory_Numeric_Column_Implementation
+    abs column =
+        Value_Type.expect_numeric column <|
+            new_name = naming_helper.concat ["abs", naming_helper.to_expression_text column]
+            apply_unary_operation column AbsOperation.INSTANCE new_name
+
+    signum column =
+        Value_Type.expect_numeric column <|
+            new_name = naming_helper.concat ["signum", naming_helper.to_expression_text column]
+            apply_unary_operation column SignumOperation.INSTANCE new_name

distribution/lib/Standard/Table/0.0.0-dev/src/Internal/Type_Refinements/Typed_Column_Helpers.enso

@@ -0,0 +1,7 @@
+import project.Refined_Types.Numeric_Column.Numeric_Column
+
+## PRIVATE
+   For internal use only, this function should be used by implementations to
+   provide a hidden conversion to `Numeric_Column` that allows the type refinement.
+make_numeric_column base_column numeric_operations_implementation =
+    Numeric_Column.Value base_column numeric_operations_implementation

distribution/lib/Standard/Table/0.0.0-dev/src/Main.enso

@@ -47,6 +47,8 @@ export project.Position.Position
 
 export project.Prefix_Name.Prefix_Name
 
+export project.Refined_Types.Numeric_Column.Numeric_Column
+
 export project.Set_Mode.Set_Mode
 
 export project.Simple_Expression.Simple_Calculation

distribution/lib/Standard/Table/0.0.0-dev/src/Refined_Types/Numeric_Column.enso

@@ -1,8 +1,31 @@
+## A column that contains numeric values.
 type Numeric_Column
     private Value column operations_implementation
 
+    ## GROUP Standard.Base.Operators
+       ICON operators
+       Computes the absolute value of each element in the column.
+
+       > Example
+         Compute the absolute value of values in a column.
+
+             import Standard.Examples
+
+             example_abs = Examples.decimal_column.abs
     abs self -> Numeric_Column =
-        "TODO"
+        self.operations_implementation.abs self.column
+
+    ## GROUP Standard.Base.Operators
+       ICON operators
+       Computes the sign of each element in the column.
+
+       It will return -1, 0 or 1 depending on the sign of the value.
+
+       > Example
+         Compute the signum of values in a column.
+
+             import Standard.Examples
 
+             example_signum = Examples.decimal_column.signum
     signum self -> Numeric_Column =
-        "TODO"
+        self.operations_implementation.signum self.column

test/Table_Tests/src/Common_Table_Operations/Main.enso

@@ -29,6 +29,7 @@ import project.Common_Table_Operations.Map_Spec
 import project.Common_Table_Operations.Map_To_Table_Spec
 import project.Common_Table_Operations.Missing_Values_Spec
 import project.Common_Table_Operations.Nothing_Spec
+import project.Common_Table_Operations.Numeric_Column_Spec
 import project.Common_Table_Operations.Offset_Spec
 import project.Common_Table_Operations.Order_By_Spec
 import project.Common_Table_Operations.Select_Columns_Spec
@@ -141,6 +142,7 @@ add_specs suite_builder setup =
     Map_To_Table_Spec.add_specs suite_builder setup
     Missing_Values_Spec.add_specs suite_builder setup
     Nothing_Spec.add_specs suite_builder setup
+    Numeric_Column_Spec.add_specs suite_builder setup
     Offset_Spec.add_specs suite_builder setup
     Order_By_Spec.add_specs suite_builder setup
     Replace_Spec.add_specs suite_builder setup

test/Table_Tests/src/Common_Table_Operations/Numeric_Column_Spec.enso

@@ -0,0 +1,57 @@
+from Standard.Base import all
+import Standard.Base.Errors.Common.Type_Error
+
+from Standard.Table import all
+from Standard.Table.Errors import all
+
+import Standard.Database.Feature.Feature
+
+from Standard.Test import all
+
+import project.Common_Table_Operations.Util
+from project.Common_Table_Operations.Util import run_default_backend
+
+type Lazy_Ref
+    Value ~get
+
+main filter=Nothing = run_default_backend add_specs filter
+
+add_specs suite_builder setup =
+    if setup.is_feature_supported Feature.Column_Operations then (add_numeric_columns_specs suite_builder setup)
+
+add_numeric_columns_specs suite_builder setup =
+    prefix = setup.prefix
+    table_builder = setup.light_table_builder
+    build_sorted_table = Util.build_sorted_table setup
+    suite_builder.group prefix+"Numeric_Column" group_builder->
+        numeric_column = Lazy_Ref.Value <| build_sorted_table [["X", [-10, 0, 1, 12]]] . at "X"
+        group_builder.specify "a numeric column can be cast to Numeric_Column" <|
+            column = numeric_column.get
+            column.value_type.is_numeric . should_be_true
+            column:Numeric_Column
+
+        group_builder.specify "a text column cannot be cast to Numeric_Column" <|
+            column = table_builder [["X", ["txt"]]] . at "X"
+            column.value_type.is_numeric . should_be_false
+            Test.expect_panic Type_Error (column:Numeric_Column)
+
+        group_builder.specify "a numeric column supports abs operation" <|
+            column = numeric_column.get
+            abs_column = (column:Numeric_Column).abs
+            abs_column.to_vector . should_equal [10, 0, 1, 12]
+
+        group_builder.specify "a numeric column supports signum operation" <|
+            column = numeric_column.get
+            signum_column = (column:Numeric_Column).signum
+            signum_column.to_vector . should_equal [-1, 0, 1, 1]
+
+        group_builder.specify "floating-point columns support abs and signum" <|
+            column = build_sorted_table [["X", [-1.5, 0.0, -0.0, 1.0, 200.25]]] . at "X"
+            abs_column = (column:Numeric_Column).abs
+            abs_column.to_vector . should_equal [1.5, 0.0, 0.0, 1.0, 200.25]
+            signum_column = (column:Numeric_Column).signum
+            signum_column.to_vector . should_equal [-1, 0, 0, 1, 1]
+
+        group_builder.specify "a single value column can also be Numeric_Column" <|
+            column = table_builder [["X", [1]]] . at "X"
+            column:Numeric_Column