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Axes.fill_between(x, y1, y2=0, where=None, interpolate=False, step=None, *, data=None, **kwargs)

Make filled polygons between two curves.

Create a PolyCollection filling the regions between y1 and y2 where where==True


x : array

An N-length array of the x data

y1 : array

An N-length array (or scalar) of the y data

y2 : array

An N-length array (or scalar) of the y data

where : array, optional

If None, default to fill between everywhere. If not None, it is an N-length numpy boolean array and the fill will only happen over the regions where where==True.

interpolate : bool, optional

If True, interpolate between the two lines to find the precise point of intersection. Otherwise, the start and end points of the filled region will only occur on explicit values in the x array.

step : {‘pre’, ‘post’, ‘mid’}, optional

If not None, fill with step logic.

See also

In addition to the above described arguments, this function can take a data keyword argument. If such a data argument is given, the following arguments are replaced by data[<arg>]: * All arguments with the following names: ‘where’, ‘x’, ‘y1’, ‘y2’.


Additional Keyword args passed on to the PolyCollection.

kwargs control the Polygon properties:

Property Description
agg_filter unknown
alpha float or None
animated [True | False]
antialiased or antialiaseds Boolean or sequence of booleans
array unknown
clim a length 2 sequence of floats
clip_box a matplotlib.transforms.Bbox instance
clip_on [True | False]
clip_path [ (Path, Transform) | Patch | None ]
cmap a colormap or registered colormap name
color matplotlib color arg or sequence of rgba tuples
contains a callable function
edgecolor or edgecolors matplotlib color spec or sequence of specs
facecolor or facecolors matplotlib color spec or sequence of specs
figure a matplotlib.figure.Figure instance
gid an id string
hatch [ ‘/’ | ‘' | ‘|’ | ‘-‘ | ‘+’ | ‘x’ | ‘o’ | ‘O’ | ‘.’ | ‘*’ ]
label string or anything printable with ‘%s’ conversion.
linestyle or dashes or linestyles [‘solid’ | ‘dashed’, ‘dashdot’, ‘dotted’ | (offset, on-off-dash-seq) | '-' | '--' | '-.' | ':' | 'None' | ' ' | '']
linewidth or linewidths or lw float or sequence of floats
norm unknown
offset_position unknown
offsets float or sequence of floats
path_effects unknown
picker [None|float|boolean|callable]
pickradius unknown
rasterized [True | False | None]
sketch_params unknown
snap unknown
transform Transform instance
url a url string
urls unknown
visible [True | False]
zorder any number