Basic lattice.

FEATURES.md

@@ -26,9 +26,11 @@ NO:
 * Maps
 * No ticks/grid
 * 3D / multi-dimensional charts
+* Annotations
 
 MAYBE:
 
 * Side-by-side bars
 * Stacked bars
 * Curved lines
+* Wrapping labels

leather/__init__.py

@@ -3,6 +3,7 @@
 from leather.axis import Axis
 from leather.chart import Chart
 from leather.grid import Grid
+from leather.lattice import Lattice
 from leather.legend import Legend
 from leather.scales.linear import LinearScale
 from leather.scales.ordinal import OrdinalScale

leather/lattice.py

@@ -0,0 +1,79 @@
+#!/usr/bin/env python
+
+from leather.chart import Chart
+from leather.data_types import Number, Text
+from leather.grid import Grid
+from leather.scales.linear import LinearScale
+from leather.scales.ordinal import OrdinalScale
+from leather.series import Series
+from leather.utils import X, Y
+
+
+class Lattice(object):
+    """
+    A grid of charts with synchronized scales.
+
+    :param data:
+         A sequence of chart data sequences.
+    """
+    def __init__(self, data, shape):
+        self._data = data
+        self._shape = shape
+
+    def _validate_dimension(self, dimension, chart_series):
+        scale = None
+        axis = None
+
+        data_type = chart_series[0].types[dimension]
+
+        for series in chart_series[1:]:
+            if series.types[dimension] is not data_type:
+                raise TypeError('All series must have the same data types.')
+
+        # Default Number scale is Linear
+        if data_type is Number:
+            data_min = min([series.min(dimension) for series in chart_series])
+            data_max = max([series.max(dimension) for series in chart_series])
+
+            scale = LinearScale(data_min, data_max)
+        # Default Text scale is Ordinal
+        elif data_type is Text:
+            scale_values = None
+
+            for series in chart_series:
+                if not scale_values:
+                    scale_values = series.values(dimension)
+                    continue
+
+                if series.values(dimension) != scale_values:
+                    raise ValueError('Mismatched series scales')
+
+            scale = OrdinalScale(scale_values)
+
+        return (scale, axis)
+
+    def to_svg(self, path, width=1200, height=1200):
+        """
+        Render the grid to an SVG.
+        """
+        chart_series = []
+
+        for seq in self._data:
+            chart_series.append(Series(seq))
+
+        x_scale, x_axis = self._validate_dimension(X, chart_series)
+        y_scale, y_axis = self._validate_dimension(Y, chart_series)
+
+        grid = Grid()
+
+        for series in chart_series:
+            chart = Chart()
+            chart.set_x_scale(x_scale)
+            chart.set_y_scale(y_scale)
+            chart.set_x_axis(x_axis)
+            chart.set_y_axis(y_axis)
+            chart.add_series(series, self._shape)
+
+            grid.add_chart(chart)
+
+        grid.to_svg(path, width, height)

test.py

@@ -42,6 +42,28 @@
 # chart.add_dot(dot_data)
 # chart.to_svg('test.svg')
 
+# data = [[
+#     (0, 3),
+#     (4, 5),
+#     (7, 9),
+#     (8, 4)
+# ], [
+#     (0, 4),
+#     (1, 3),
+#     (2, 5),
+#     (5, 6),
+#     (9, 10)
+# ]]
+#
+# grid = leather.Grid()
+#
+# for series in data:
+#     chart = leather.Chart()
+#     chart.add_line(series)
+#     grid.add_chart(chart)
+#
+# grid.to_svg('test.svg', 1200, 600)
+
 data = [[
     (0, 3),
     (4, 5),
@@ -50,16 +72,23 @@
 ], [
     (0, 4),
     (1, 3),
-    (2, 5),
-    (5, 6),
-    (9, 10)
+    (2, 3),
+    (10, 7),
+    (15, 5)
+], [
+    (0, 4),
+    (5, 5),
+    (6, 6),
+    (7, 7),
+    (8, 8)
+], [
+    (4, 4),
+    (6, 3),
+    (7, 5),
+    (8, 6),
+    (12, 10)
 ]]
 
-grid = leather.Grid()
-
-for series in data:
-    chart = leather.Chart()
-    chart.add_line(series)
-    grid.add_chart(chart)
+lattice = leather.Lattice(data, leather.Line())
 
-grid.to_svg('test.svg', 1200, 600)
+lattice.to_svg('test.svg', 1200, 600)