ENH: Add bt.plot(reverse_indicators=) param

Author: kernc

backtesting/_plotting.py

@@ -150,6 +150,7 @@ def plot(*, results: pd.Series,
          plot_volume=True, plot_drawdown=False,
          smooth_equity=False, relative_equity=True,
          superimpose=True, resample=True,
+         reverse_indicators=True,
          show_legend=True, open_browser=True):
     """
     Like much of GUI code everywhere, this is a mess.
@@ -494,6 +495,7 @@ def __eq__(self, other):
                 return self is other
 
         ohlc_colors = colorgen()
+        indicator_figs = []
 
         for i, value in enumerate(indicators):
             value = np.atleast_2d(value)
@@ -509,7 +511,7 @@ def __eq__(self, other):
                 fig = fig_ohlc
             else:
                 fig = new_indicator_figure()
-                figs_below_ohlc.append(fig)
+                indicator_figs.append(fig)
             tooltips = []
             colors = value._opts['color']
             colors = colors and cycle(_as_list(colors)) or (
@@ -562,6 +564,7 @@ def __eq__(self, other):
                 # have the legend only contain text without the glyph
                 if len(value) == 1:
                     fig.legend.glyph_width = 0
+        return indicator_figs
 
     # Construct figure ...
 
@@ -583,7 +586,10 @@ def __eq__(self, other):
 
     ohlc_bars = _plot_ohlc()
     _plot_ohlc_trades()
-    _plot_indicators()
+    indicator_figs = _plot_indicators()
+    if reverse_indicators:
+        indicator_figs = indicator_figs[::-1]
+    figs_below_ohlc.extend(indicator_figs)
 
     set_tooltips(fig_ohlc, ohlc_tooltips, vline=True, renderers=[ohlc_bars])
 

backtesting/backtesting.py

@@ -1280,7 +1280,7 @@ def plot(self, *, results: pd.Series = None, filename=None, plot_width=None,
              plot_volume=True, plot_drawdown=False,
              smooth_equity=False, relative_equity=True,
              superimpose: Union[bool, str] = True,
-             resample=True,
+             resample=True, reverse_indicators=False,
              show_legend=True, open_browser=True):
         """
         Plot the progression of the last backtest run.
@@ -1339,6 +1339,9 @@ def plot(self, *, results: pd.Series = None, filename=None, plot_width=None,
         used to resample, overriding above numeric limitation.
         Note, all this only works for data with a datetime index.
 
+        If `reverse_indicators` is `True`, the indicators below the OHLC chart
+        are plotted in reverse order of declaration.
+
         [Pandas offset string]: \
             https://pandas.pydata.org/pandas-docs/stable/user_guide/timeseries.html#dateoffset-objects
 
@@ -1369,5 +1372,6 @@ def plot(self, *, results: pd.Series = None, filename=None, plot_width=None,
             relative_equity=relative_equity,
             superimpose=superimpose,
             resample=resample,
+            reverse_indicators=reverse_indicators,
             show_legend=show_legend,
             open_browser=open_browser)

backtesting/test/_test.py

@@ -421,6 +421,7 @@ def test_params(self):
                           resample='1W',
                           smooth_equity=False,
                           relative_equity=False,
+                          reverse_indicators=True,
                           show_legend=False).items():
                 with self.subTest(param=p[0]):
                     bt.plot(**dict([p]), filename=f, open_browser=False)