Improve Shape error handling. Union Ordinal series. Closes #76.

CHANGELOG.rst

@@ -1,7 +1,8 @@
 0.3.3
 -----
 
-
+* Ordinal scales can now display data from multiple series with different values. (#76)
+* Better error handling for data types supported by different shapes.
 
 0.3.2 - November 11, 2016
 -------------------------

leather/scales/base.py

@@ -80,13 +80,25 @@ def infer(cls, layers, dimension, data_type):
         elif data_type is Text:
             scale_values = None
 
-            for series, shape in layers:
-                if scale_values is None:
-                    scale_values = series.values(dimension)
-                    continue
-
-                if series.values(dimension) != scale_values:
-                    raise ValueError('All series must have the same values for scale display.')
+            # First case: a single set of ordinal labels
+            if len(layers) == 1:
+                scale_values = layers[0][0].values(dimension)
+            else:
+                first_series = set(layers[0][0].values(dimension))
+                data_series = [series.values(dimension) for series, shape in layers]
+                all_same = True
+
+                for series in data_series:
+                    if set(series) != first_series:
+                        all_same = False
+                        break
+
+                # Second case: multiple identical sets of ordinal labels
+                if all_same:
+                    scale_values = layers[0][0].values(dimension)
+                # Third case: multiple different sets of ordinal labels
+                else:
+                    scale_values = sorted(list(set().union(*data_series)))
 
             scale = Ordinal(scale_values)
 

leather/series/base.py

@@ -26,8 +26,6 @@ class Series(object):
 
         Or, a custom data format, in which case :code:`x` and :code:`y` must
         specify :func:`.key_function`.
-    :param shape:
-        An instance of :class:`.Shape` to use to render this data.
     :param x:
         If using sequence row data, then this may be either an integer index
         identifying the X column, or a :func:`.key_function`.
@@ -77,14 +75,20 @@ def _infer_type(self, key):
                 break
 
         if v is None:
-            raise ValueError('All values in dimension was null.')
+            raise ValueError('All values in dimension were null.')
 
         return DataType.infer(v)
 
     @property
     def name(self):
         return self._name
 
+    def data_type(self, dimension):
+        """
+        Return the data type for a dimension of this series.
+        """
+        return self._types[dimension]
+
     def data(self):
         """
         Return data for this series.

leather/shapes/bars.py

@@ -4,9 +4,11 @@
 
 import six
 
+from leather.data_types import Number, Text
 from leather.series import CategorySeries
 from leather.shapes.base import Shape
 from leather import theme
+from leather.utils import X, Y
 
 
 class Bars(Shape):
@@ -27,6 +29,12 @@ def validate_series(self, series):
         if isinstance(series, CategorySeries):
             raise ValueError('Bars can not be used to render CategorySeries.')
 
+        if series.data_type(X) is not Number:
+            raise ValueError('Bars only support Number values for the Y axis.')
+
+        if series.data_type(Y) is not Text:
+            raise ValueError('Bars only support Text values for the X axis.')
+
     def to_svg(self, width, height, x_scale, y_scale, series, palette):
         """
         Render bars to SVG elements.

leather/shapes/columns.py

@@ -4,8 +4,10 @@
 
 import six
 
+from leather.data_types import Number, Text
 from leather.series import CategorySeries
 from leather.shapes.base import Shape
+from leather.utils import X, Y
 
 
 class Columns(Shape):
@@ -26,6 +28,12 @@ def validate_series(self, series):
         if isinstance(series, CategorySeries):
             raise ValueError('Columns can not be used to render CategorySeries.')
 
+        if series.data_type(X) is not Text:
+            raise ValueError('Bars only support Text values for the X axis.')
+
+        if series.data_type(Y) is not Number:
+            raise ValueError('Bars only support Number values for the Y axis.')
+
     def to_svg(self, width, height, x_scale, y_scale, series, palette):
         """
         Render columns to SVG elements.

leather/shapes/dots.py

@@ -5,10 +5,11 @@
 
 import six
 
+from leather.data_types import Text
 from leather.series import CategorySeries
 from leather.shapes.base import Shape
 from leather import theme
-from leather.utils import DummySeries
+from leather.utils import DummySeries, X, Y
 
 
 class Dots(Shape):
@@ -32,6 +33,9 @@ def validate_series(self, series):
         """
         Verify this shape can be used to render a given series.
         """
+        if series.data_type(X) is Text or series.data_type(Y) is Text:
+            raise ValueError('Dots do not support Text values.')
+
         return True
 
     def to_svg(self, width, height, x_scale, y_scale, series, palette):

leather/shapes/line.py

@@ -4,9 +4,11 @@
 
 import six
 
+from leather.data_types import Text
 from leather.series import CategorySeries
 from leather.shapes.base import Shape
 from leather import theme
+from leather.utils import X, Y
 
 
 class Line(Shape):
@@ -30,6 +32,9 @@ def validate_series(self, series):
         if isinstance(series, CategorySeries):
             raise ValueError('Line can not be used to render CategorySeries.')
 
+        if series.data_type(X) is Text or series.data_type(Y) is Text:
+            raise ValueError('Line does not support Text values.')
+
     def _new_path(self, stroke_color):
         """
         Start a new path.

test.py

@@ -4,12 +4,28 @@
 
 import leather
 
-data = [
-    (0, 'foo'),
-    (5, u'👍'),
-    (10, 'bar')
+# data1 = [
+#     (2, 'foo'),
+#     (6, 'bar'),
+#     (9, 'bing')
+# ]
+#
+# data2 = [
+#     (3, 'foo'),
+#     (5, 'bar'),
+#     (7, 'bing')
+# ]
+#
+# lattice = leather.Lattice(shape=leather.Bars())
+# lattice.add_many([data1, data2])
+# lattice.to_svg('test.svg')
+
+data1 = [
+    (2, None),
+    (6, None),
+    (9, None)
 ]
 
-chart = leather.Chart('Dots')
-chart.add_bars(data)
+chart = leather.Chart()
+chart.add_bars(data1)
 chart.to_svg('test.svg')

tests/test_lattice.py

@@ -40,3 +40,47 @@ def test_add_many(self):
         self.assertElementCount(svg, '.axis', 6)
         self.assertElementCount(svg, '.series', 3)
         self.assertElementCount(svg, '.lines', 3)
+
+    def test_bars(self):
+        data1 = [
+            (2, 'foo'),
+            (6, 'bar'),
+            (9, 'bing')
+        ]
+
+        data2 = [
+            (3, 'foo'),
+            (5, 'bar'),
+            (7, 'bing')
+        ]
+
+        lattice = leather.Lattice(shape=leather.Bars())
+        lattice.add_many([data1, data2])
+
+        svg = self.render_chart(lattice)
+
+        self.assertElementCount(svg, '.axis', 4)
+        self.assertElementCount(svg, '.series', 2)
+        self.assertElementCount(svg, '.bars', 2)
+
+    def test_bars_different(self):
+        data1 = [
+            (3, 'foo'),
+            (5, 'bar'),
+            (9, 'bing')
+        ]
+
+        data2 = [
+            (3, 'foo'),
+            (5, 'bar'),
+            (9, 'baz')
+        ]
+
+        lattice = leather.Lattice(shape=leather.Bars())
+        lattice.add_many([data1, data2])
+
+        svg = self.render_chart(lattice)
+
+        self.assertElementCount(svg, '.axis', 4)
+        self.assertElementCount(svg, '.series', 2)
+        self.assertElementCount(svg, '.bars', 2)

tests/test_shapes.py

@@ -54,6 +54,20 @@ def test_zeros(self):
         self.assertEqual(float(rects[1].get('x')), 0)
         self.assertEqual(float(rects[1].get('width')), 0)
 
+    def test_validate(self):
+        series = leather.Series([
+            (1, 'foo')
+        ])
+
+        self.shape.validate_series(series)
+
+        series = leather.Series([
+            ('foo', 1)
+        ])
+
+        with self.assertRaises(ValueError):
+            self.shape.validate_series(series)
+
 
 class TestColumns(leather.LeatherTestCase):
     def setUp(self):
@@ -90,6 +104,20 @@ def test_nulls(self):
         self.assertEqual(float(rects[1].get('y')), 0)
         self.assertEqual(float(rects[1].get('height')), 100)
 
+    def test_validate(self):
+        series = leather.Series([
+            ('foo', 1)
+        ])
+
+        self.shape.validate_series(series)
+
+        series = leather.Series([
+            (1, 'foo')
+        ])
+
+        with self.assertRaises(ValueError):
+            self.shape.validate_series(series)
+
 
 class TestDots(leather.LeatherTestCase):
     def setUp(self):
@@ -140,6 +168,20 @@ def test_nulls(self):
         self.assertEqual(float(circles[1].get('cx')), 200)
         self.assertEqual(float(circles[1].get('cy')), 0)
 
+    def test_validate(self):
+        series = leather.Series([
+            (1, 1)
+        ])
+
+        self.shape.validate_series(series)
+
+        series = leather.Series([
+            (1, 'foo')
+        ])
+
+        with self.assertRaises(ValueError):
+            self.shape.validate_series(series)
+
 
 class TestLine(leather.LeatherTestCase):
     def setUp(self):
@@ -183,3 +225,17 @@ def test_nulls(self):
         paths = list(group)
 
         self.assertEqual(len(paths), 2)
+
+    def test_validate(self):
+        series = leather.Series([
+            (1, 1)
+        ])
+
+        self.shape.validate_series(series)
+
+        series = leather.Series([
+            (1, 'foo')
+        ])
+
+        with self.assertRaises(ValueError):
+            self.shape.validate_series(series)