forked from 170010011/fr
118 lines
3.8 KiB
Python
118 lines
3.8 KiB
Python
|
"""
|
||
|
|
Stacked area plot for 1D arrays inspired by Douglas Y'barbo's stackoverflow
|
||
|
|
answer:
|
||
|
|
http://stackoverflow.com/questions/2225995/how-can-i-create-stacked-line-graph-with-matplotlib
|
||
|
|
|
||
|
|
(http://stackoverflow.com/users/66549/doug)
|
||
|
|
|
||
|
|
"""
|
||
|
|
import numpy as np
|
||
|
|
|
||
|
|
import matplotlib.cbook as cbook
|
||
|
|
|
||
|
|
__all__ = ['stackplot']
|
||
|
|
|
||
|
|
|
||
|
|
def stackplot(axes, x, *args,
|
||
|
|
labels=(), colors=None, baseline='zero',
|
||
|
|
**kwargs):
|
||
|
|
"""
|
||
|
|
Draw a stacked area plot.
|
||
|
|
|
||
|
|
Parameters
|
||
|
|
----------
|
||
|
|
x : 1d array of dimension N
|
||
|
|
|
||
|
|
y : 2d array (dimension MxN), or sequence of 1d arrays (each dimension 1xN)
|
||
|
|
|
||
|
|
The data is assumed to be unstacked. Each of the following
|
||
|
|
calls is legal::
|
||
|
|
|
||
|
|
stackplot(x, y) # where y is MxN
|
||
|
|
stackplot(x, y1, y2, y3, y4) # where y1, y2, y3, y4, are all 1xNm
|
||
|
|
|
||
|
|
baseline : {'zero', 'sym', 'wiggle', 'weighted_wiggle'}
|
||
|
|
Method used to calculate the baseline:
|
||
|
|
|
||
|
|
- ``'zero'``: Constant zero baseline, i.e. a simple stacked plot.
|
||
|
|
- ``'sym'``: Symmetric around zero and is sometimes called
|
||
|
|
'ThemeRiver'.
|
||
|
|
- ``'wiggle'``: Minimizes the sum of the squared slopes.
|
||
|
|
- ``'weighted_wiggle'``: Does the same but weights to account for
|
||
|
|
size of each layer. It is also called 'Streamgraph'-layout. More
|
||
|
|
details can be found at http://leebyron.com/streamgraph/.
|
||
|
|
|
||
|
|
labels : Length N sequence of strings
|
||
|
|
Labels to assign to each data series.
|
||
|
|
|
||
|
|
colors : Length N sequence of colors
|
||
|
|
A list or tuple of colors. These will be cycled through and used to
|
||
|
|
colour the stacked areas.
|
||
|
|
|
||
|
|
**kwargs
|
||
|
|
All other keyword arguments are passed to `.Axes.fill_between`.
|
||
|
|
|
||
|
|
Returns
|
||
|
|
-------
|
||
|
|
list of `.PolyCollection`
|
||
|
|
A list of `.PolyCollection` instances, one for each element in the
|
||
|
|
stacked area plot.
|
||
|
|
"""
|
||
|
|
|
||
|
|
y = np.row_stack(args)
|
||
|
|
|
||
|
|
labels = iter(labels)
|
||
|
|
if colors is not None:
|
||
|
|
axes.set_prop_cycle(color=colors)
|
||
|
|
|
||
|
|
# Assume data passed has not been 'stacked', so stack it here.
|
||
|
|
# We'll need a float buffer for the upcoming calculations.
|
||
|
|
stack = np.cumsum(y, axis=0, dtype=np.promote_types(y.dtype, np.float32))
|
||
|
|
|
||
|
|
cbook._check_in_list(['zero', 'sym', 'wiggle', 'weighted_wiggle'],
|
||
|
|
baseline=baseline)
|
||
|
|
if baseline == 'zero':
|
||
|
|
first_line = 0.
|
||
|
|
|
||
|
|
elif baseline == 'sym':
|
||
|
|
first_line = -np.sum(y, 0) * 0.5
|
||
|
|
stack += first_line[None, :]
|
||
|
|
|
||
|
|
elif baseline == 'wiggle':
|
||
|
|
m = y.shape[0]
|
||
|
|
first_line = (y * (m - 0.5 - np.arange(m)[:, None])).sum(0)
|
||
|
|
first_line /= -m
|
||
|
|
stack += first_line
|
||
|
|
|
||
|
|
elif baseline == 'weighted_wiggle':
|
||
|
|
total = np.sum(y, 0)
|
||
|
|
# multiply by 1/total (or zero) to avoid infinities in the division:
|
||
|
|
inv_total = np.zeros_like(total)
|
||
|
|
mask = total > 0
|
||
|
|
inv_total[mask] = 1.0 / total[mask]
|
||
|
|
increase = np.hstack((y[:, 0:1], np.diff(y)))
|
||
|
|
below_size = total - stack
|
||
|
|
below_size += 0.5 * y
|
||
|
|
move_up = below_size * inv_total
|
||
|
|
move_up[:, 0] = 0.5
|
||
|
|
center = (move_up - 0.5) * increase
|
||
|
|
center = np.cumsum(center.sum(0))
|
||
|
|
first_line = center - 0.5 * total
|
||
|
|
stack += first_line
|
||
|
|
|
||
|
|
# Color between x = 0 and the first array.
|
||
|
|
color = axes._get_lines.get_next_color()
|
||
|
|
coll = axes.fill_between(x, first_line, stack[0, :],
|
||
|
|
facecolor=color, label=next(labels, None),
|
||
|
|
**kwargs)
|
||
|
|
coll.sticky_edges.y[:] = [0]
|
||
|
|
r = [coll]
|
||
|
|
|
||
|
|
# Color between array i-1 and array i
|
||
|
|
for i in range(len(y) - 1):
|
||
|
|
color = axes._get_lines.get_next_color()
|
||
|
|
r.append(axes.fill_between(x, stack[i, :], stack[i + 1, :],
|
||
|
|
facecolor=color, label=next(labels, None),
|
||
|
|
**kwargs))
|
||
|
|
return r
|