seaborn.countplot

seaborn.countplot(x=None, y=None, hue=None, data=None, order=None, hue_order=None, orient=None, color=None, palette=None, saturation=0.75, dodge=True, ax=None, **kwargs)

Show the counts of observations in each categorical bin using bars.

A count plot can be thought of as a histogram across a categorical, instead of quantitative, variable. The basic API and options are identical to those for barplot(), so you can compare counts across nested variables.

Input data can be passed in a variety of formats, including:

• Vectors of data represented as lists, numpy arrays, or pandas Series objects passed directly to the x, y, and/or hue parameters.
• A “long-form” DataFrame, in which case the x, y, and hue variables will determine how the data are plotted.
• A “wide-form” DataFrame, such that each numeric column will be plotted.
• An array or list of vectors.

In most cases, it is possible to use numpy or Python objects, but pandas objects are preferable because the associated names will be used to annotate the axes. Additionally, you can use Categorical types for the grouping variables to control the order of plot elements.

This function always treats one of the variables as categorical and draws data at ordinal positions (0, 1, … n) on the relevant axis, even when the data has a numeric or date type.

See the color_palette(), or a dictionary mapping hue levels to matplotlib colors.

saturation：float, optional

Proportion of the original saturation to draw colors at. Large patches often look better with slightly desaturated colors, but set this to 1 if you want the plot colors to perfectly match the input color spec.

dodge：bool, optional

When hue nesting is used, whether elements should be shifted along the categorical axis.

ax：matplotlib Axes, optional

Axes object to draw the plot onto, otherwise uses the current Axes.

kwargs：key, value mappings

Other keyword arguments are passed to plt.bar.

返回值：ax：matplotlib Axes

Returns the Axes object with the plot drawn onto it.

See also

Show point estimates and confidence intervals using bars.Combine a categorical plot with a class:FacetGrid.

Examples

Show value counts for a single categorical variable:

>>> import seaborn as sns
>>> sns.set(style="darkgrid")
>>> titanic = sns.load_dataset("titanic")
>>> ax = sns.countplot(x="class", data=titanic)

Show value counts for two categorical variables:

>>> ax = sns.countplot(x="class", hue="who", data=titanic)

Plot the bars horizontally:

>>> ax = sns.countplot(y="class", hue="who", data=titanic)

Use a different color palette:

>>> ax = sns.countplot(x="who", data=titanic, palette="Set3")

Use plt.bar keyword arguments for a different look:

>>> ax = sns.countplot(x="who", data=titanic,
...                    facecolor=(0, 0, 0, 0),
...                    linewidth=5,
...                    edgecolor=sns.color_palette("dark", 3))

Use catplot() to combine a countplot() and a FacetGrid. This allows grouping within additional categorical variables. Using catplot() is safer than using FacetGrid directly, as it ensures synchronization of variable order across facets:

>>> g = sns.catplot(x="class", hue="who", col="survived",
...                 data=titanic, kind="count",
...                 height=4, aspect=.7);