Define the stacked histogram function
We will define a function to create a stacked histogram. The function will take the following parameters:
ax: the axes to add artists tostacked_data: a (M, N) shaped array. The first dimension will be iterated over to compute histograms row-wisesty_cycle: a Cycler or operable of dict, style to apply to each setbottoms: an array, default: 0, the initial positions of the bottoms.hist_func: a callable, optional. Must have signature bin_vals, bin_edges = f(data). bin_edges expected to be one longer than bin_valslabels: a list of strings, optional, the label for each set. If not given and stacked data is an array defaults to 'default set {n}'. If stacked_data is a mapping and labels is None, default to the keys. If stacked_data is a mapping and labels is given then only the columns listed will be plotted.plot_func: a callable, optional, function to call to draw the histogram. Must have signature ret = plot_func(ax, edges, top, bottoms=bottoms, label=label, **kwargs)plot_kwargs: a dictionary, optional, any extra keyword arguments to pass through to the plotting function. This will be the same for all calls to the plotting function and will override the values in sty_cycle.
def stack_hist(ax, stacked_data, sty_cycle, bottoms=None, hist_func=None, labels=None, plot_func=None, plot_kwargs=None):
"""
Parameters
----------
ax : axes.Axes
The axes to add artists too
stacked_data : array or Mapping
A (M, N) shaped array. The first dimension will be iterated over to
compute histograms row-wise
sty_cycle : Cycler or operable of dict
Style to apply to each set
bottoms : array, default: 0
The initial positions of the bottoms.
hist_func : callable, optional
Must have signature `bin_vals, bin_edges = f(data)`.
`bin_edges` expected to be one longer than `bin_vals`
labels : list of str, optional
The label for each set.
If not given and stacked data is an array defaults to 'default set {n}'
If *stacked_data* is a mapping, and *labels* is None, default to the
keys.
If *stacked_data* is a mapping and *labels* is given then only the
columns listed will be plotted.
plot_func : callable, optional
Function to call to draw the histogram must have signature:
ret = plot_func(ax, edges, top, bottoms=bottoms,
label=label, **kwargs)
plot_kwargs : dict, optional
Any extra keyword arguments to pass through to the plotting function.
This will be the same for all calls to the plotting function and will
override the values in *sty_cycle*.
Returns
-------
arts : dict
Dictionary of artists keyed on their labels
"""
## deal with default binning function
if hist_func is None:
hist_func = np.histogram
## deal with default plotting function
if plot_func is None:
plot_func = filled_hist
## deal with default
if plot_kwargs is None:
plot_kwargs = {}
try:
l_keys = stacked_data.keys()
label_data = True
if labels is None:
labels = l_keys
except AttributeError:
label_data = False
if labels is None:
labels = itertools.repeat(None)
if label_data:
loop_iter = enumerate((stacked_data[lab], lab, s) for lab, s in zip(labels, sty_cycle))
else:
loop_iter = enumerate(zip(stacked_data, labels, sty_cycle))
arts = {}
for j, (data, label, sty) in loop_iter:
if label is None:
label = f'dflt set {j}'
label = sty.pop('label', label)
vals, edges = hist_func(data)
if bottoms is None:
bottoms = np.zeros_like(vals)
top = bottoms + vals
sty.update(plot_kwargs)
ret = plot_func(ax, edges, top, bottoms=bottoms, label=label, **sty)
bottoms = top
arts[label] = ret
ax.legend(fontsize=10)
return arts
