diff --git a/doc/fig/heatmap.png b/doc/fig/heatmap.png
Binary files a/doc/fig/heatmap.png and b/doc/fig/heatmap.png differ
diff --git a/plot-light.cabal b/plot-light.cabal
--- a/plot-light.cabal
+++ b/plot-light.cabal
@@ -1,5 +1,5 @@
 name:                plot-light
-version:             0.2.5
+version:             0.2.6
 synopsis:            A lightweight plotting library, exporting to SVG
 description:         This library provides drawing and plotting datastructures and functions; it is aimed in particular at scientific visualization, but it also exposes its plotting primitives and a general purpose 2D geometry library.
 homepage:            https://github.com/ocramz/plot-light
diff --git a/src/Graphics/Rendering/Plot/Light.hs b/src/Graphics/Rendering/Plot/Light.hs
--- a/src/Graphics/Rendering/Plot/Light.hs
+++ b/src/Graphics/Rendering/Plot/Light.hs
@@ -24,7 +24,15 @@
 -- 
 -- === 1. Heatmap plot of a 2D function
 --
--- <<doc/fig/heatmap.png#diagram=heatmap&height=200&width=266>>
+-- <<doc/fig/heatmap.png>>
+--
+-- This example renders the function
+--
+-- \[
+-- {f(x, y) = \cos(\pi \theta) \sin( \rho^2) }
+-- \]
+-- where
+-- \( \rho^2 = x^2 + y^2 \) and \( \theta = \arctan(y/x) \).
 --
 -- > import qualified Data.Text.IO as T (readFile, writeFile)
 -- > import qualified Data.Text as T
diff --git a/src/Graphics/Rendering/Plot/Light/Internal.hs b/src/Graphics/Rendering/Plot/Light/Internal.hs
--- a/src/Graphics/Rendering/Plot/Light/Internal.hs
+++ b/src/Graphics/Rendering/Plot/Light/Internal.hs
@@ -89,8 +89,8 @@
 
 -- | A rectangle, defined by its center coordinates and side lengths
 --
--- > > putStrLn $ renderSvg $ rectCentered (Point 20 30) 15 30 (Just C.blue) (Just C.red)
--- > <g transform="translate(12.5 15.0)"><rect width="15.0" height="30.0" fill="#ff0000" stroke="#0000ff" /></g>
+-- > > putStrLn $ renderSvg $ rectCentered 15 30 1 (Just C.blue) (Just C.red) (Point 20 30)
+-- > <rect x="12.5" y="15.0" width="15.0" height="30.0" fill="#ff0000" stroke="#0000ff" stroke-width="1.0" />
 rectCentered :: (Show a, RealFrac a) =>
      a                       -- ^ Width
   -> a                       -- ^ Height