Add .sum to Vector (#1702)

distribution/std-lib/Standard/src/Base/Data/Range.enso

@@ -35,14 +35,28 @@ type Range
     not_empty : Boolean
     not_empty = this.is_empty.not
 
+    ## Applies a function to each element in the range, producing a vector of
+       results.
+
+       Arguments:
+       - function: The function to apply to each integer in the range.
+
+       > Example
+         Create a vector that contains the numbers twice that of the numbers in
+         the range.
+
+             1.up_to 10 . map (*2)
+    map : (Number -> Any) -> Vector Any
+    map function = this.to_vector.map function
+
     ## Applies a function for each element in the range.
 
        Arguments:
        - function: The function to apply to each integer in the range.
 
        > Example
          To print all the numbers from 1 to 100 use:
-         1.up_to 101 . each IO.println
+             1.up_to 101 . each IO.println
     each : (Number -> Any) -> Nothing
     each function =
         it start end = if start == end then Nothing else
@@ -130,5 +144,7 @@ type Range
          Getting a vector of the numbers 1 to 5.
              1.up_to 6 . to_vector == [1, 2, 3, 4, 5]
     to_vector : Vector.Vector
-    to_vector = Vector.new (this.end - 1) (i -> i + this.start)
+    to_vector =
+        length = Math.max 0 (this.end - this.start)
+        Vector.new length (i -> i + this.start)
 

distribution/std-lib/Standard/src/Base/Data/Vector.enso

@@ -173,6 +173,24 @@ type Vector
             True -> this.tail.fold this.head function
             False -> Error.throw Nothing
 
+    ## Computes the sum of the values in the vector.
+
+       For this method to be defined, the elements of the vector must be able to
+       have the `+` operator used to combine them.
+
+       > Example
+         In the following example, we'll compute the sum of all elements of a
+         vector.
+
+             [0, 1, 2].sum
+    sum : (Any ! Nothing)
+    sum =
+        result = Panic.recover <| this.reduce (+)
+        result.map_error x->case x of
+            No_Such_Method_Error _ _ -> Nothing
+            Nothing -> Nothing
+            _ -> Panic.throw x
+
     ## Checks whether a predicate holds for at least one element of this vector.
 
        Arguments:

distribution/std-lib/Standard/src/Visualization/Scatter_Plot.enso

@@ -23,7 +23,7 @@ label_field = 'label'
 
 ## PRIVATE
    Represents a recognized point data field for a scatter plot visualization.
-type PointData 
+type PointData
     ## PRIVATE
     type PointData
     ## PRIVATE
@@ -72,15 +72,13 @@ type PointData
     ## PRIVATE
        Returns a vector of subsequent integers beginning from 0.
     iota : Number -> Vector
-    iota count = 
-        # FIXME [mwu]: Adjust once https://github.com/enso-org/enso/issues/1439
-        #              is addressed.
-        range = 0.up_to <| count + 1
+    iota count =
+        range = 0.up_to count
         Column.from_vector here.index_name range.to_vector
 
     ## PRIVATE
     lookup_in : Table -> Column
-    lookup_in table = 
+    lookup_in table =
         named = table.lookup_ignore_case this.name
         named.catch_ <| this.fallback_column table
 
@@ -90,7 +88,7 @@ Table.Table.point_data : Table -> Object
 Table.Table.point_data =
     get_point_data field = field.lookup_in this . rename field.name
     columns = PointData.all_fields.filter_map get_point_data
-    (0.up_to <| this.row_count + 1).to_vector.map <| row_n-> 
+    (0.up_to this.row_count).to_vector.map <| row_n->
         pairs = columns.map column->
             value = column.at row_n . catch_ Nothing
             [column.name, value]
@@ -100,7 +98,7 @@ Table.Table.point_data =
     Generates JSON that describes plot axes.
 Table.Table.axes : Table -> Object
 Table.Table.axes =
-    describe_axis field = 
+    describe_axis field =
         col_name = field.lookup_in this . name
         label = Json.from_pairs [[here.label_field, col_name]]
         [field.name, label]
@@ -114,33 +112,33 @@ Table.Table.axes =
 
 ## PRIVATE
 Vector.Vector.point_data : Vector -> Object
-Vector.Vector.point_data = 
-        this.map_with_index <| i-> elem-> 
+Vector.Vector.point_data =
+        this.map_with_index <| i-> elem->
             Json.from_pairs [[X.name,i],[Y.name,elem]]
 
 ## PRIVATE
 
-json_from_table table = 
+json_from_table table =
     data = table.point_data
     axes = table.axes
     Json.from_pairs <| [[here.data_field,data], [here.axis_field, axes]]
 
 ## PRIVATE
-json_from_vector vec = 
+json_from_vector vec =
     data = [here.data_field, vec.point_data]
     axes = [here.axis_field, Nothing]
     Json.from_pairs [data, axes]
 
 ## PRIVATE
 
    Default preprocessor for the scatterplot visualization.
-   
+
    Generates JSON text describing the scatterplot visualization.
-   
+
    Arguments:
    - value: the value to be visualized.
 process_to_json_text : Any -> Text
-process_to_json_text value = 
+process_to_json_text value =
     json = case value of
         Column.Column _ -> here.json_from_table  value.to_table
         Table.Table _   -> here.json_from_table  value

test/Tests/src/Data/Range_Spec.enso

@@ -20,6 +20,11 @@ spec = Test.group "Range" <|
         0.up_to -100 . not_empty . should_be_false
         0.up_to 1 . not_empty . should_be_true
         0.up_to 5 . not_empty . should_be_true
+    Test.specify "should be able to be mapped over to make a Vector" <|
+        empty = 0.up_to 0
+        empty.map *2 . should_equal []
+        elements = 0.up_to 10
+        elements.map *2 . should_equal [0, 2, 4, 6, 8, 10, 12, 14, 16, 18]
     Test.specify "should allow iteration" <|
         vec_mut = Vector.new_builder
         1.up_to 6 . each (i -> vec_mut.append i)

test/Tests/src/Data/Vector_Spec.enso

@@ -38,6 +38,11 @@ spec = Test.group "Vectors" <|
         [1,2,3].reduce (+) . should_equal 6
         [].reduce (+) . should_fail_with Nothing
 
+    Test.specify "should allow summing elements if they define +" <|
+        [1,2,3].sum . should_equal 6
+        [].sum . should_fail_with Nothing
+        [T 1 2, T 3 4].sum . should_fail_with Nothing
+
     Test.specify "should check exists" <|
         vec = [1, 2, 3, 4, 5]
         vec.exists (ix -> ix > 3) . should_be_true

test/Visualization_Tests/src/Histogram_Spec.enso

@@ -6,7 +6,7 @@ import Standard.Test
 import Standard.Visualization.Histogram
 import Visualization_Tests
 
-spec = 
+spec =
     expect value expected_label expected_values =
         text = Histogram.process_to_json_text value
         json = Json.parse text
@@ -20,7 +20,7 @@ spec =
         json.should_equal expected_json
 
     Test.group "Histogram Visualization" <|
-    
+
         Test.specify "deals with an empty table" <|
             table  = Table.from_rows [] []
             expect table Nothing []
@@ -30,14 +30,14 @@ spec =
             row_1  = [11 , 10 ]
             row_2  = [21 , 20 ]
             table  = Table.from_rows header [row_1, row_2]
-            expect table 'α' [11,21]          
+            expect table 'α' [11,21]
 
         Test.specify "plots first column if none recognized even if index" <|
             header = ['α']
             row_1  = [11 ]
             row_2  = [21 ]
             table  = Table.from_rows header [row_1, row_2] . set_index 'α'
-            expect table 'α' [11,21]     
+            expect table 'α' [11,21]
 
         Test.specify "plots 'value' numeric column if present" <|
             header = ['α', 'value']
@@ -55,12 +55,12 @@ spec =
 
         Test.specify "plots column" <|
             column = Column.from_vector 'my_name' [1,4,6]
-            expect column 'my_name' [1,4,6]    
-        
+            expect column 'my_name' [1,4,6]
+
         Test.specify "plots vector" <|
             vector = [1,2,3]
             expect vector Nothing vector
 
         Test.specify "plots range" <|
-            vector = 2.up_to 4
+            vector = 2.up_to 5
             expect vector Nothing [2,3,4]

test/Visualization_Tests/src/Scatter_Plot_Spec.enso

@@ -8,7 +8,7 @@ import Standard.Visualization.Scatter_Plot
 import Visualization_Tests
 
 spec =
-    expect value axis_expected_text data_expected_text = 
+    expect value axis_expected_text data_expected_text =
         text = Scatter_Plot.process_to_json_text value
         json = Json.parse text
         json.fields.keys.should_equal ['axis','data']
@@ -24,37 +24,37 @@ spec =
     no_labels  = 'null'
 
     Test.group "Scatter Plot Visualization" <|
-    
+
         Test.specify "deals with an empty table" <|
             table  = Table.from_rows [] []
             expect table 'null' '[]'
-    
+
         Test.specify "plots first column if none recognized" <|
             header = ['α', 'ω']
             row_1  = [11 , 10 ]
             row_2  = [21 , 20 ]
             table  = Table.from_rows header [row_1, row_2]
             expect table (labels index 'α') '[{"x":0,"y":11},{"x":1,"y":21}]'
-    
+
         Test.specify "plots 'y' against indices when no 'x' recognized" <|
             header = ['α', 'y']
             row_1 =  [11 , 10 ]
             row_2 =  [21 , 20 ]
             table = Table.from_rows header [row_1, row_2]
             expect table (labels index 'y') '[{"x":0,"y":10},{"x":1,"y":20}]'
-            
+
         Test.specify "recognizes all relevant columns" <|
             header = ['x' , 'y' , 'size' , 'shape'  , 'label' , 'color' ]
             row_1 =  [11  , 10  , 50     , 'square' , 'label' , 'ff0000']
             table = Table.from_rows header [row_1]
             expect table (labels 'x' 'y') '[{"color":"ff0000","label":"label","shape":"square","size":50,"x":11,"y":10}]'
-            
+
         Test.specify "is case insensitive" <|
             header = ['X' , 'Y' , 'Size' , 'Shape'  , 'Label' , 'Color' ]
             row_1 =  [11  , 10  , 50     , 'square' , 'label' , 'ff0000']
             table = Table.from_rows header [row_1]
             expect table (labels 'X' 'Y') '[{"color":"ff0000","label":"label","shape":"square","size":50,"x":11,"y":10}]'
-            
+
         Test.specify "uses first unrecognized numeric column as `y` fallback" <|
             header = ['x' , 'size' , 'name'   , 'z' , 'ω']
             row_1 =  [11  , 50     , 'circul' ,  20 ,  30]
@@ -99,5 +99,5 @@ spec =
             expect column (labels 'index' 'some_col') '[{"x":0,"y":10},{"x":1,"y":2},{"x":2,"y":3}]'
 
         Test.specify "using indices for x if given a range" <|
-            value = 2.up_to 4
+            value = 2.up_to 5
             expect value no_labels '[{"x":0,"y":2},{"x":1,"y":3},{"x":2,"y":4}]'