use axis reversal instead of adhoc type

Author: clayrat

chart-tests/tests/Test20.hs

@@ -38,7 +38,7 @@ dat = [ [66.22192174833207,   50.85424119528999]
       , [4.73981774972079753, 5.092283613261595367]
       ]
 
-chart :: Renderable (LayoutPick LogValue PlotIndexRev PlotIndexRev)
+chart :: Renderable (LayoutPick LogValue PlotIndex PlotIndex)
 chart = layoutToRenderable layout
  where
   layout =
@@ -58,17 +58,18 @@ chart = layoutToRenderable layout
       $ layout_bottom_axis_visibility . axis_show_ticks .~ True
 
       -- Y
-      $ layout_y_axis . laxis_generate .~ autoIndexRevTicksAxis alabels
+      $ layout_y_axis . laxis_generate .~ autoIndexAxis' True alabels
       $ layout_y_axis . laxis_override .~ axisGridAtTicks
+      $ layout_y_axis . laxis_reverse .~ True
       $ layout_y_axis . laxis_style . axis_grid_style .~ solidLine 0.3 (opaque lightgrey)
       $ layout_left_axis_visibility . axis_show_ticks .~ False
 
       -- data
       $ layout_plots .~ [ plotHBars bars2 ]
 
-      $ def :: Layout LogValue PlotIndexRev
+      $ def :: Layout LogValue PlotIndex
 
-  bars2 = plot_bars_values_with_labels .~ addRevIndexes dat'
+  bars2 = plot_bars_values_with_labels .~ addIndexes dat'
       $ plot_bars_titles .~ ["","after","before"]
       $ plot_bars_style .~ BarsStacked
       $ plot_bars_spacing .~ BarsFixGap 12 5

chart/Graphics/Rendering/Chart/Axis/Indexed.hs

@@ -11,14 +11,9 @@
 
 module Graphics.Rendering.Chart.Axis.Indexed(
     PlotIndex(..),
-    PlotIndexRev(..),
     autoIndexAxis',
     autoIndexAxis,
-    autoIndexTicksAxis,
-    autoIndexRevAxis,
-    autoIndexRevTicksAxis,
     addIndexes,
-    addRevIndexes,
 ) where
 
 import Data.Default.Class
@@ -39,31 +34,16 @@ instance PlotValue PlotIndex where
 addIndexes :: [a] -> [(PlotIndex,a)]
 addIndexes = zipWith (\n x -> (PlotIndex n, x)) [0..]
 
--- | Indices in a reverse order
-newtype PlotIndexRev = PlotIndexRev { plotindexr_i :: Int }
-  deriving (Eq,Ord,Enum,Num,Real,Integral,Show)
-
-instance PlotValue PlotIndexRev where
-    toValue (PlotIndexRev i) = fromIntegral i
-    fromValue                = PlotIndexRev . round
-    autoAxis                 = autoIndexRevAxis []
-
--- | Augment a list of values with reversed index numbers for plotting.
-addRevIndexes :: [a] -> [(PlotIndexRev,a)]
-addRevIndexes xs =
-  let l = length xs in
-  zipWith (\n x -> (PlotIndexRev (l - n - 1), x)) [0..] xs
-
 -- | Create an axis for values indexed by position. The
 --   list of strings are the labels to be used.
-autoIndexAxis' :: Integral i => Bool -> Bool -> [String] -> AxisFn i
-autoIndexAxis' rev tks labels vs = AxisData {
+autoIndexAxis' :: Integral i => Bool -> [String] -> AxisFn i
+autoIndexAxis' tks labels vs = AxisData {
     _axis_visibility = def { _axis_show_ticks = False },
     _axis_viewport = vport,
     _axis_tropweiv = invport,
     _axis_ticks    = if tks then map (, 5) $ take (length labels) [0..] else [],
     _axis_labels   = [filter (\(i,_) -> i >= imin && i <= imax)
-                             (zip [0..] (if rev then reverse labels else labels))],
+                             (zip [0..] labels)],
     _axis_grid     = []
     }
   where
@@ -74,13 +54,4 @@ autoIndexAxis' rev tks labels vs = AxisData {
     imax = maximum vs
 
 autoIndexAxis :: Integral i => [String] -> AxisFn i
-autoIndexAxis = autoIndexAxis' False False
-
-autoIndexTicksAxis :: Integral i => [String] -> AxisFn i
-autoIndexTicksAxis = autoIndexAxis' False True
-
-autoIndexRevAxis :: Integral i => [String] -> AxisFn i
-autoIndexRevAxis = autoIndexAxis' True False
-
-autoIndexRevTicksAxis :: Integral i => [String] -> AxisFn i
-autoIndexRevTicksAxis = autoIndexAxis' True True
+autoIndexAxis = autoIndexAxis' False