backend investigations of flashing (see Shlomi Golubev email).

Author: DanielGoldfarb

Diff for: examples/scratch_pad/find.valid.backends.py

@@ -0,0 +1,60 @@
+from __future__ import print_function, division, absolute_import
+from pylab import *
+import time
+
+import matplotlib.backends
+import matplotlib.pyplot as p
+import os.path
+
+
+def is_backend_module(fname):
+    """Identifies if a filename is a matplotlib backend module"""
+    return fname.startswith('backend_') and fname.endswith('.py')
+
+def backend_fname_formatter(fname): 
+    """Removes the extension of the given filename, then takes away the leading 'backend_'."""
+    return os.path.splitext(fname)[0][8:]
+
+# get the directory where the backends live
+backends_dir = os.path.dirname(matplotlib.backends.__file__)
+
+# filter all files in that directory to identify all files which provide a backend
+backend_fnames = filter(is_backend_module, os.listdir(backends_dir))
+
+backends = [backend_fname_formatter(fname) for fname in backend_fnames]
+
+print("supported backends: \t" + str(backends))
+
+# validate backends
+backends_valid = []
+for b in backends:
+    try:
+        p.switch_backend(b)
+        backends_valid += [b]
+    except:
+        continue
+
+print("valid backends: \t" + str(backends_valid))
+
+
+# try backends performance
+for b in backends_valid:
+
+    ion()
+    try:
+        p.switch_backend(b)
+
+
+        clf()
+        tstart = time.time()               # for profiling
+        x = arange(0,2*pi,0.01)            # x-array
+        line, = plot(x,sin(x))
+        for i in arange(1,200):
+            line.set_ydata(sin(x+i/10.0))  # update the data
+            draw()                         # redraw the canvas
+
+        print(b + ' FPS: \t' , 200/(time.time()-tstart))
+        ioff()
+
+    except:
+        print(b + " error :(")

Diff for: examples/scratch_pad/run.valid.ibackends.py

@@ -0,0 +1,34 @@
+import matplotlib.pyplot as plt
+import matplotlib as mpl
+from   pylab import *
+
+##  ==================================================================================
+##  supported backends:     ['ps', 'webagg', 'qt4agg', 'agg', 'wx', 'svg', 'qt5agg',
+##                           'template', 'gtk3cairo', 'pdf', 'qt5cairo', 'macosx', 
+##                           'qt4', 'gtk3agg', 'nbagg', 'webagg_core', 'wxcairo',
+##                           'qt5', 'gtk3', 'mixed', 'tkagg', 'qt4cairo', 'tkcairo',
+##                           'wxagg', 'pgf', 'cairo']
+##  valid backends:         ['ps', 'webagg', 'agg', 'svg', 'template', 'pdf', 'nbagg',
+##                           'tkagg', 'pgf']
+##  ps FPS:          1823.8522934563061
+##  webagg FPS:      7169.995555403603
+##  agg FPS:         20.852366968595575
+##  svg FPS:         3809.921063866508
+##  template FPS:    23.202661861618655
+##  pdf FPS:         2901.3876399053693
+##  <IPython.core.display.Javascript object>
+##  <IPython.core.display.HTML object>
+##  nbagg error :(
+##  tkagg FPS:       2901.929636420244
+##  pgf FPS:         5311.09436829276
+##  ==================================================================================
+
+x = arange(0,2*pi,0.01)
+
+#for b in ['tkagg','webagg','nbagg']:
+#for b in ['tkagg','nbagg']:
+for b in ['tkagg','Qt5Agg']:
+    mpl.use(b)
+    print('Backend: ',plt.get_backend())
+    plt.plot(x,sin(x))
+    plt.show()

Diff for: src/mplfinance/plotting.py

@@ -3,6 +3,7 @@
 import matplotlib.colors as mcolors
 import matplotlib.axes   as mpl_axes
 import matplotlib.figure as mpl_fig
+import matplotlib.ticker as mtk
 import pandas as pd
 import numpy  as np
 import copy
@@ -471,6 +472,13 @@ def plot( data, **kwargs ):
         if collection is not None:
             axA1.add_collection(collection)
 
+    xrotation = config['xrotation']
+    if not external_axes_mode:
+        _set_ticks_on_bottom_panel_only(panels,formatter,rotation=xrotation)
+    else:
+        axA1.tick_params(axis='x',rotation=xrotation)
+        axA1.xaxis.set_major_formatter(formatter)
+
     datalen = len(xdates)
     if config['volume']:
         vup,vdown = style['marketcolors']['volume'].values()
@@ -488,13 +496,6 @@ def plot( data, **kwargs ):
         maxy = 1.1 * np.nanmax(volumes)
         volumeAxes.set_ylim( miny, maxy )
 
-    xrotation = config['xrotation']
-    if not external_axes_mode:
-        _set_ticks_on_bottom_panel_only(panels,formatter,rotation=xrotation)
-    else:
-        axA1.tick_params(axis='x',rotation=xrotation)
-        axA1.xaxis.set_major_formatter(formatter)
-
     addplot = config['addplot']
     if addplot is not None and ptype not in VALID_PMOVE_TYPES:
         # NOTE: If in external_axes_mode, then all code relating
@@ -609,9 +610,14 @@ def plot( data, **kwargs ):
     axA1.set_ylabel(config['ylabel'])
 
     if config['volume']:
-        volumeAxes.figure.canvas.draw()  # This is needed to calculate offset
-        offset = volumeAxes.yaxis.get_major_formatter().get_offset()
-        volumeAxes.yaxis.offsetText.set_visible(False)
+        if external_axes_mode:
+            volumeAxes.tick_params(axis='x',rotation=xrotation)
+            volumeAxes.xaxis.set_major_formatter(formatter)
+        #volumeAxes.figure.canvas.draw()  # This is needed to calculate offset
+        volumeAxes.yaxis.set_major_formatter(mtk.FormatStrFormatter('%.0e'))
+        #offset = volumeAxes.yaxis.get_major_formatter().get_offset()
+        #volumeAxes.yaxis.offsetText.set_visible(False)
+        offset = ''
         if len(offset) > 0:
             offset = (' x '+offset)
         if config['ylabel_lower'] is None:
@@ -621,9 +627,6 @@ def plot( data, **kwargs ):
                 offset = '\n'+offset
             vol_label = config['ylabel_lower'] + offset
         volumeAxes.set_ylabel(vol_label)
-        if external_axes_mode:
-            volumeAxes.tick_params(axis='x',rotation=xrotation)
-            volumeAxes.xaxis.set_major_formatter(formatter)
 
     if config['title'] is not None:
         if config['tight_layout']: