问题
I've been struggling to recreate this Excel graph in python using matlplotlib:
The data is in a dataframe; I'm trying to automate the process of generating this graph.
I've tried unstacking my dataframe, subplotting, but I haven't managed to create the "Zone" index which is so elegant in Excel. I have successfully managed to plot the graph without this "Zone" index, but that's not really what I want to do.
Here is my code:
data = pd.DataFrame(
{
'Factory Zone':
["AMERICAS","APAC","APAC","APAC","APAC","APAC","EMEA","EMEA","EMEA","EMEA"],
'Factory Name':
["Chocolate Factory","Crayon Factory","Jobs Ur Us", "Gibberish US","Lil Grey", "Toys R Us","Food Inc.",
"Pet Shop", "Bonbon Factory","Carrefour"],
'Production Day 1':
[24,1,9,29,92,79,4,90,42,35],
'Production Day 2':
[2,43,17,5,31,89,44,49,34,84]
})
df = pd.DataFrame(data)
print(df)
# Without FactoryZone, it works:
df = df.drop(['Factory Zone'], axis=1)
image = df.plot(kind="bar")
And the data looks like this:
Unnamed: 0 FactoryZone Factory Name Production Day 1 Production Day 2
0 1 AMERICAS Chocolate Factory 24 43
1 2 AMERICAS Crayon Factory 1 17
2 3 EMEA Pet Shop 9 5
3 4 EMEA Bonbon Factory 29 31
4 5 APAC Lil Grey 92 89
5 6 AMERICAS Jobs Ur Us 79 44
6 7 APAC Toys R Us 4 49
7 8 EMEA Carrefour 90 34
8 9 AMERICAS Gibberish US 42 84
9 10 APAC Food Inc. 35 62
回答1:
An idea that gives a close plot is to plot to each Factory Zone in a subplot that are place next to each other:
# setting up the subplots
fig, axes = plt.subplots(1, len(df['Factory Zone'].unique()),
figsize=(12,4),
sharex=True, sharey=True,
gridspec_kw={'wspace':0},
subplot_kw={'frameon':False})
# use groupby to loop through the `Factory Zone`
for (k,d), ax in zip(df.groupby('Factory Zone'), axes):
# plot the data into subplot
d.plot.bar(x='Factory Name', ax=ax)
# set label to the `Factory Zone`
ax.set_xlabel(k)
# remove the extra legend in each subplot
legend = ax.legend()
handlers = ax.get_legend_handles_labels()
ax.legend().remove()
ax.grid(True, axis='y')
# reinstall the last legend
ax.legend(*handlers)
Output:
回答2:
You can create this plot by first creating a MultiIndex for your hierarchical dataset where level 0 is the Factory Zone and level 1 is the Factory Name:
import numpy as np # v 1.19.2
import pandas as pd # v 1.1.3
import matplotlib.pyplot as plt # v 3.3.2
df = pd.DataFrame(
{'Factory Zone': ['AMERICAS', 'AMERICAS', 'AMERICAS', 'AMERICAS', 'APAC',
'APAC', 'APAC', 'EMEA', 'EMEA', 'EMEA'],
'Factory Name': ['Chocolate Factory', 'Crayon Factory', 'Jobs Ur Us',
'Gibberish US', 'Lil Grey', 'Toys R Us', 'Food Inc.',
'Pet Shop', 'Bonbon Factory','Carrefour'],
'Production Day 1': [24,1,9,29,92,79,4,90,42,35],
'Production Day 2': [2,43,17,5,31,89,44,49,34,84]
})
df.set_index(['Factory Zone', 'Factory Name'], inplace=True)
df
# Production Day 1 Production Day 2
# Factory Zone Factory Name
# AMERICAS Chocolate Factory 24 2
# Crayon Factory 1 43
# Jobs Ur Us 9 17
# Gibberish US 29 5
# APAC Lil Grey 92 31
# Toys R Us 79 89
# Food Inc. 4 44
# EMEA Pet Shop 90 49
# Bonbon Factory 42 34
# Carrefour 35 84
Like Quang Hoang has proposed, you can create a subplot for each zone and stick them together. The width of each subplot must be corrected according to the number of factories by using the width_ratios argument in the gridspec_kw dictionary so that all the columns have the same width. Then there are limitless formatting choices to make.
In the following example, I choose to show separation lines only between zones by using the minor tick marks for this purpose. Also, because the figure width is limited here to 10 inches only, I rewrite the longer labels on two lines.
# Create figure with a subplot for each factory zone with a relative width
# proportionate to the number of factories
zones = df.index.levels[0]
nplots = zones.size
plots_width_ratios = [df.xs(zone).index.size for zone in zones]
fig, axes = plt.subplots(nrows=1, ncols=nplots, sharey=True, figsize=(10, 4),
gridspec_kw = dict(width_ratios=plots_width_ratios, wspace=0))
# Loop through array of axes to create grouped bar chart for each factory zone
alpha = 0.3 # used for grid lines, bottom spine and separation lines between zones
for zone, ax in zip(zones, axes):
# Create bar chart with grid lines and no spines except bottom one
df.xs(zone).plot.bar(ax=ax, legend=None, zorder=2)
ax.grid(axis='y', zorder=1, color='black', alpha=alpha)
for spine in ['top', 'left', 'right']:
ax.spines[spine].set_visible(False)
ax.spines['bottom'].set_alpha(alpha)
# Set and place x labels for factory zones
ax.set_xlabel(zone)
ax.xaxis.set_label_coords(x=0.5, y=-0.2)
# Format major tick labels for factory names: note that because this figure is
# only about 10 inches wide, I choose to rewrite the long names on two lines.
ticklabels = [name.replace(' ', '\n') if len(name) > 10 else name
for name in df.xs(zone).index]
ax.set_xticklabels(ticklabels, rotation=0, ha='center')
ax.tick_params(axis='both', length=0, pad=7)
# Set and format minor tick marks for separation lines between zones: note
# that except for the first subplot, only the right tick mark is drawn to avoid
# duplicate overlapping lines so that when an alpha different from 1 is chosen
# (like in this example) all the lines look the same
if ax.is_first_col():
ax.set_xticks([*ax.get_xlim()], minor=True)
else:
ax.set_xticks([ax.get_xlim()[1]], minor=True)
ax.tick_params(which='minor', length=55, width=0.8, color=[0, 0, 0, alpha])
# Add legend using the labels and handles from the last subplot
fig.legend(*ax.get_legend_handles_labels(), frameon=False, loc=(0.08, 0.77))
fig.suptitle('Production Quantity by Zone and Factory on both days', y=1.02, size=14);
References: the answer by Quang Hoang, this answer by gyx-hh
来源：https://stackoverflow.com/questions/66016045/python-dataframe-plot-a-bar-chart-for-data-frame-with-grouped-by-columns-at-l