Add SVG helper file.

leather/chart.py

@@ -13,7 +13,8 @@
 from leather.shapes.column import Column
 from leather.shapes.dot import Dot
 from leather.shapes.line import Line
-from leather.utils import X, Y, DIMENSIONS, Box, svg_translate
+import leather.svg as svg
+from leather.utils import X, Y, DIMENSIONS, Box
 
 DEFAULT_DOT = Dot()
 DEFAULT_LINE = Line()
@@ -166,7 +167,7 @@ def to_svg_group(self, width, height, margin=None):
         canvas_height = height - (margin.top + margin.bottom)
 
         root_group = ET.Element('g')
-        root_group.set('transform', svg_translate(margin.left, margin.top))
+        root_group.set('transform', svg.translate(margin.left, margin.top))
 
         # Axes
         axes_group = ET.Element('g')
@@ -195,15 +196,15 @@ def to_svg(self, path, width=600, height=600, margin=None):
         :param path:
             Filepath or file-like object to write to.
         """
-        svg = ET.Element('svg',
+        root = ET.Element('svg',
             width=six.text_type(width),
             height=six.text_type(height),
             version='1.1',
             xmlns='http://www.w3.org/2000/svg'
         )
 
         group = self.to_svg_group(width, height, margin)
-        svg.append(group)
+        root.append(group)
 
         close = True
 
@@ -219,10 +220,8 @@ def to_svg(self, path, width=600, height=600, margin=None):
 
                 f = open(path, 'w')
 
-            f.write('<?xml version="1.0" standalone="no"?>\n')
-            f.write('<!DOCTYPE svg PUBLIC "-//W3C//DTD SVG 1.1//EN"\n')
-            f.write('"http://www.w3.org/Graphics/SVG/1.1/DTD/svg11.dtd">\n')
-            f.write(ET.tostring(svg, encoding='unicode'))
+            f.write(svg.HEADER)
+            f.write(ET.tostring(root, encoding='unicode'))
             f.close()
         finally:
             if close and f is not None:

leather/grid.py

@@ -6,7 +6,7 @@
 
 import six
 
-from leather.utils import svg_translate
+import leather.svg as svg
 
 
 class Grid(object):
@@ -26,7 +26,7 @@ def to_svg(self, path, width=1200, height=1200):
         """
         Render the grid to an SVG.
         """
-        svg = ET.Element('svg',
+        root = ET.Element('svg',
             width=six.text_type(width),
             height=six.text_type(height),
             version='1.1',
@@ -44,12 +44,12 @@ def to_svg(self, path, width=1200, height=1200):
             y = math.floor(i / grid_width) * chart_height
 
             group = ET.Element('g')
-            group.set('transform', svg_translate(x, y))
+            group.set('transform', svg.translate(x, y))
 
             chart = chart.to_svg_group(chart_width, chart_height)
             group.append(chart)
-            
-            svg.append(group)
+
+            root.append(group)
 
         close = True
 
@@ -65,10 +65,8 @@ def to_svg(self, path, width=1200, height=1200):
 
                 f = open(path, 'w')
 
-            f.write('<?xml version="1.0" standalone="no"?>\n')
-            f.write('<!DOCTYPE svg PUBLIC "-//W3C//DTD SVG 1.1//EN"\n')
-            f.write('"http://www.w3.org/Graphics/SVG/1.1/DTD/svg11.dtd">\n')
-            f.write(ET.tostring(svg, encoding='unicode'))
+            f.write(svg.HEADER)
+            f.write(ET.tostring(root, encoding='unicode'))
             f.close()
         finally:
             if close and f is not None:

leather/svg.py

@@ -0,0 +1,12 @@
+#!/usr/bin/env python
+
+"""
+Helpers for working with SVG.
+"""
+
+HEADER = '<?xml version="1.0" standalone="no"?>\n' + \
+    '<!DOCTYPE svg PUBLIC "-//W3C//DTD SVG 1.1//EN"\n' + \
+    '"http://www.w3.org/Graphics/SVG/1.1/DTD/svg11.dtd">\n'
+
+def translate(x, y):
+    return 'translate(%i %i)' % (x, y)

leather/utils.py

@@ -13,6 +13,3 @@
 
 #: Data structure for representing margins or other CSS-edge like properties
 Box = namedtuple('Box', ['top', 'right', 'bottom', 'left'])
-
-def svg_translate(x, y):
-    return 'translate(%i %i)' % (x, y)