check length of overrides; allow (0-255) format for rgb

Author: DanielGoldfarb

examples/marketcolor_overrides.ipynb

@@ -1,9 +1,8 @@
 import matplotlib.dates  as mdates
-import matplotlib.colors as mcolors
 import pandas   as pd
 import numpy    as np
 import datetime
-from   mplfinance._helpers import _list_of_dict
+from   mplfinance._helpers import _list_of_dict, _mpf_is_color_like
 import matplotlib as mpl
 import warnings
 
@@ -364,19 +363,20 @@ def _is_marketcolor_object(obj):
     if not isinstance(obj,dict): return False
     market_colors_keys = ('candle','edge','wick','ohlc')
     return all([k in obj for k in market_colors_keys])
-    
 
-def _mco_validator(value):  # marketcolor overrides validator
-    if isinstance(value,dict):     # not yet supported, but maybe we will have other
-        if 'colors' not in value:  # kwargs related to mktcolor overrides (ex: `mco_faceonly`)
+
+def _mco_validator(value):        # marketcolor overrides validator
+    if isinstance(value,dict):    # not yet supported, but maybe we will have other
+        if 'colors' not in value: # kwargs related to mktcolor overrides (ex: `mco_faceonly`)
             raise ValueError('`marketcolor_overrides` as dict must contain `colors` key.')
         colors = value['colors']
     else:
         colors = value
     if not isinstance(colors,(list,tuple,np.ndarray)):
         return False
-    return all([(c is None or mcolors.is_color_like(c) or _is_marketcolor_object(c)) for c in colors])
-
+    return all([(c is None or 
+                 _mpf_is_color_like(c) or
+                 _is_marketcolor_object(c) ) for c in colors])
 
 def _check_for_external_axes(config):
     '''

src/mplfinance/_arg_validators.py

@@ -1,9 +1,13 @@
 """
 Some helper functions for mplfinance.
+NOTE: This is the lowest level in mplfinance:
+      This file should have NO dependencies on
+      any other mplfinance files.
 """
 
 import datetime
-import matplotlib.dates as mdates
+import matplotlib.dates  as mdates
+import matplotlib.colors as mcolors
 import numpy as np
 
 def _adjust_color_brightness(color,amount=0.5):
@@ -82,3 +86,36 @@ def roundTime(dt=None, roundTo=60):
    seconds = (dt.replace(tzinfo=None) - dt.min).seconds
    rounding = (seconds+roundTo/2) // roundTo * roundTo
    return dt + datetime.timedelta(0,rounding-seconds,-dt.microsecond)
+
+
+def _is_uint8_rgb_or_rgba(tup):
+    """ Deterine if rgb or rgba is in (0-255) format:
+    Matplotlib expects rgb (and rgba) tuples to contain
+    three (or four) floats between 0.0 and 1.0 
+    
+    Some people express rgb as tuples of three integers
+    between 0 and 255.
+    (In rgba, alpha is still a float from 0.0 to 1.0)
+    """
+    if isinstance(tup,str):  return False
+    if not np.iterable(tup): return False
+    L = len(tup)
+    if L < 3 or L > 4: return False
+    if L == 4 and (tup[3] < 0 or tup[3] > 1): return False
+    return not any([not isinstance(v,(int,np.unsignedinteger)) or v<0 or v>255 for v in tup[0:3]])
+
+def _mpf_is_color_like(c):
+    """Determine if an object is a color.
+    
+    Identical to `matplotlib.colors.is_color_like()`
+    BUT ALSO considers int (0-255) rgb and rgba colors.
+    """
+    if mcolors.is_color_like(c): return True
+    return _is_uint8_rgb_or_rgba(c)
+    
+def _mpf_to_rgba(c, alpha=None):
+    cnew = c
+    if _is_uint8_rgb_or_rgba(c) and any(e>1 for e in c[:3]):
+        cnew = tuple([e/255. for e in c[:3]])
+        if len(c) == 4: cnew += c[3:]
+    return mcolors.to_rgba(cnew, alpha)

src/mplfinance/_helpers.py

@@ -1,11 +1,11 @@
 import matplotlib.pyplot as plt
-import matplotlib.colors as mcolors
 import copy
 import pprint
 import os.path as path
 
 from   mplfinance._arg_validators import _process_kwargs, _validate_vkwargs_dict
 from   mplfinance._styledata      import _styles
+from   mplfinance._helpers        import _mpf_is_color_like
 
 
 def _get_mpfstyle(style):
@@ -70,7 +70,7 @@ def _valid_make_mpf_style_kwargs():
                             'Validator'   : lambda value: isinstance(value,dict)  },
 
         'mavcolors'     : { 'Default'     : None,
-                            'Validator'   : lambda value: isinstance(value,list) },  # TODO: all([mcolors.is_color_like(v) for v in value.values()])
+                            'Validator'   : lambda value: isinstance(value,list) },  # TODO: all([_mpf_is_color_like(v) for v in value.values()])
 
         'facecolor'     : { 'Default'     : None,
                             'Validator'   : lambda value: isinstance(value,str) },
@@ -153,10 +153,10 @@ def make_mpf_style( **kwargs ):
 
 def _valid_mpf_color_spec(value):
     'value must be a color, "inherit"-like, or dict of colors'
-    return ( mcolors.is_color_like(value) or 
+    return ( _mpf_is_color_like(value) or 
              ( isinstance(value,str) and value == 'inherit'[0:len(value)]) or
              ( isinstance(value,dict) and
-               all([mcolors.is_color_like(v) for v in value.values()])
+               all([_mpf_is_color_like(v) for v in value.values()])
              )
            )
 
@@ -190,13 +190,13 @@ def _valid_mpf_style(value):
 def _valid_make_marketcolors_kwargs():
     vkwargs = {
         'up'         : { 'Default'     : None,
-                         'Validator'   : lambda value: mcolors.is_color_like(value) },
+                         'Validator'   : lambda value: _mpf_is_color_like(value) },
 
         'down'       : { 'Default'     : None,
-                         'Validator'   : lambda value: mcolors.is_color_like(value) },
+                         'Validator'   : lambda value: _mpf_is_color_like(value) },
 
         'hollow'     : { 'Default'     : None,
-                         'Validator'   : lambda value: mcolors.is_color_like(value) },
+                         'Validator'   : lambda value: _mpf_is_color_like(value) },
 
         'alpha'      : { 'Default'     : None,
                          'Validator'   : lambda value: ( isinstance(value,float) and
@@ -208,17 +208,17 @@ def _valid_make_marketcolors_kwargs():
         'wick'       : { 'Default'     : None,
                          'Validator'   : lambda value: isinstance(value,dict)
                                                        or isinstance(value,str) 
-                                                       or mcolors.is_color_like(value) },
+                                                       or _mpf_is_color_like(value) },
 
         'ohlc'       : { 'Default'     : None,
                          'Validator'   : lambda value: isinstance(value,dict)
                                                        or isinstance(value,str) 
-                                                       or mcolors.is_color_like(value) },
+                                                       or _mpf_is_color_like(value) },
 
         'volume'     : { 'Default'   : None,
                          'Validator'   : lambda value: isinstance(value,dict)
                                                        or isinstance(value,str) 
-                                                       or mcolors.is_color_like(value) },
+                                                       or _mpf_is_color_like(value) },
 
         'vcdopcod'   : { 'Default'     : False,
                          'Validator'   : lambda value: isinstance(value,bool) },
@@ -282,7 +282,7 @@ def _check_and_set_mktcolor(candle,**kwarg):
         else:
             colors = dict(up=value, down=value)
         for updown in ['up','down']:
-            if not mcolors.is_color_like(colors[updown]):
+            if not _mpf_is_color_like(colors[updown]):
                 err = f'NOT is_color_like() for {key}[\'{updown}\'] = {colors[updown]}'
                 raise ValueError(err)
         return colors

src/mplfinance/_styles.py

@@ -17,6 +17,7 @@
 from mplfinance._arg_validators import _alines_validator, _bypass_kwarg_validation
 from mplfinance._arg_validators import _xlim_validator, _is_datelike
 from mplfinance._styles         import _get_mpfstyle
+from mplfinance._helpers        import _mpf_to_rgba
 
 from six.moves import zip
 
@@ -603,7 +604,7 @@ def _construct_candlestick_collections(dates, opens, highs, lows, closes, market
     faceonly  = config['mco_faceonly']
 
     colors    = _make_updown_color_list('candle',marketcolors,opens,closes,overrides)
-    colors    = [mcolors.to_rgba(c,alpha) for c in colors] # include alpha
+    colors    = [ _mpf_to_rgba(c,alpha) for c in colors ] # include alpha
     if faceonly: overrides = None
     edgecolor = _make_updown_color_list('edge',marketcolors,opens,closes,overrides)
     wickcolor = _make_updown_color_list('wick',marketcolors,opens,closes,overrides)

src/mplfinance/_utils.py

@@ -306,6 +306,10 @@ def plot( data, **kwargs ):
         err = "`addplot` is not supported for `type='" + config['type'] +"'`"
         raise ValueError(err)
 
+    if config['marketcolor_overrides'] is not None:
+        if len(config['marketcolor_overrides']) != len(dates):
+            raise ValueError('`marketcolor_overrides` must be same length as dataframe.')
+
     external_axes_mode = _check_for_external_axes(config)
 
     if external_axes_mode: