pandas python 图例未显示所有颜色类别

Question

I am trying to plot a graph using dataframe values, I have three columns in the dataframe, column one is the legend values of the graph, column two is the x axis and column third is the y-axis. When I am plotting the graph it is only showing me one category in the legend not all, its showing me only one color

This is my dataframe

This is my code

ax1 = graphdf.plot(kind='bar', x='Bottles', y='bottle Avg')
figures = graphdf['fig'].tolist()
ax1.legend(labels=figures, fancybox=True, shadow=True)
for p in ax1.patches:
    label1 = "{:.1f}".format(p.get_height())
    ax1.annotate(label1, xy=(p.get_x() * 1.015, p.get_height() * 1.015))

but this is only showing 1 categories in the label not all.

This is the output, I want to show all categories in the legend

Answer 1

In this usage pandas.DataFrame.plot.bar calls matplotlib.pyplot.bar exactly once, creating a single collection of patches with a single label. The matplotlib.axes.Axes.legend signature where only the labels are specified simply assigns labels to " existing plot elements ". Since plt.bar creates a single "plot element" only one legend entry is created. You can easily get around this by using the third call signature for ax.legend , where both the labels and handles are specified, ie

ax = df.plot(kind='bar', x='Bottles', y='bottle Avg')
ax.legend(labels=df['fig'].tolist(), handles=ax.patches, fancybox=True, shadow=True)
for p in ax.patches:
    ax.annotate("{:.1f}".format(p.get_height()), xy=(p.get_x() * 1.015, p.get_height() * 1.015))