def lowess(x, y, span=SPAN):
"returns y-values estimated using the lowess function in statsmodels."
"""
for more see
statsmodels.nonparametric.smoothers_lowess.lowess
"""
x, y = map(_plot_friendly, [x, y])
if _isdate(x[0]):
x = np.array([i.toordinal() for i in x])
result = smlowess(np.array(y), np.array(x), frac=span)
x = pd.Series(result[::, 0])
y = pd.Series(result[::, 1])
lower, upper = stats.t.interval(span, len(x), loc=0, scale=2)
std = np.std(y)
y1 = pd.Series(lower * std + y)
y2 = pd.Series(upper * std + y)
return (y, y1, y2)
def lowess(x, y, span=SPAN):
"returns y-values estimated using the lowess function in statsmodels."
"""
for more see
statsmodels.nonparametric.smoothers_lowess.lowess
"""
x, y = map(plot_friendly, [x,y])
if _isdate(x[0]):
x = np.array([i.toordinal() for i in x])
result = smlowess(np.array(y), np.array(x), frac=span)
x = pd.Series(result[::,0])
y = pd.Series(result[::,1])
lower, upper = stats.t.interval(span, len(x), loc=0, scale=2)
std = np.std(y)
y1 = pd.Series(lower * std + y)
y2 = pd.Series(upper * std + y)
return (y, y1, y2)