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matplotlib.pyplot.fill_betweenx(y, x1, x2=0, where=None, step=None, interpolate=False, hold=None, data=None, **kwargs)

Make filled polygons between two horizontal curves.

Create a PolyCollection filling the regions between x1 and x2 where where==True


y : array

An N-length array of the y data

x1 : array

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

x2 : array, optional

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

where : array, optional

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

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

If not None, fill with step logic.

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.

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’, ‘x1’, ‘x2’, ‘y’.


keyword args passed on to the

kwargs control the Polygon properties:

Property Description
agg_filter a filter function, which takes a (m, n, 3) float array and a dpi value, and returns a (m, n, 3) array
alpha float or None
animated bool
antialiased or antialiaseds Boolean or sequence of booleans
array ndarray
clim a length 2 sequence of floats
clip_box a Bbox instance
clip_on bool
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 Figure instance
gid an id string
hatch [ ‘/’ | ‘' | ‘|’ | ‘-‘ | ‘+’ | ‘x’ | ‘o’ | ‘O’ | ‘.’ | ‘*’ ]
label object
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 Normalize
offset_position [ ‘screen’ | ‘data’ ]
offsets float or sequence of floats
path_effects AbstractPathEffect
picker [None | bool | float | callable]
pickradius float distance in points
rasterized bool or None
sketch_params (scale: float, length: float, randomness: float)
snap bool or None
transform Transform
url a url string
urls List[str] or None
visible bool
zorder float