[FIXED] Plot multiple stacked bar in the same figure

Issue

i would like to multiple stacked bar in the same plot. This is my code:

    file_to_plot = file_to_plot.set_index(['user'])
    fig, ax = plt.subplots()
    fontP = FontProperties()
    fontP.set_size('small')
    file_to_plot[[" mean_accuracy_all_classes_normal", " delta_all_classes"]].plot(ax=ax, kind='bar', color= ['g', 'r'], width = 0.65, align="center", stacked=True)
    file_to_plot[[" mean_accuracy_user_classes_normal", " delta_user_classes"]].plot(ax=ax, kind='bar', color=['y', 'b'], width=0.65, align="center", stacked = True)
    lgd = ax.legend(['Tutte le classi (normale)', 'Tutte le classi (incrementale)', 'Classi utente (normale)', 'Classi utente (incrementale)'], prop=fontP, loc=9, bbox_to_anchor=(0.5, -0.15), ncol=4,borderaxespad=0.)
    ax.set_ylabel('% Accuratezza')
    ax.set_xlabel('Utenti')

This is the results:

The second plot overwhelms me when I want to plot them together. How can I do?

Solution

This should work the way you want:

import pandas as pd

df = pd.DataFrame(dict(
    A=[1, 2, 3, 4],
    B=[2, 3, 4, 5],
    C=[3, 4, 5, 6],
    D=[4, 5, 6, 7]))

import matplotlib.pyplot as plt
%matplotlib inline
fig = plt.figure(figsize=(20, 10))

ab_bar_list = [plt.bar([0, 1, 2, 3], df.B, align='edge', width= 0.2),
               plt.bar([0, 1, 2, 3], df.A, align='edge', width= 0.2)]

cd_bar_list = [plt.bar([0, 1, 2, 3], df.D, align='edge',width= -0.2),
               plt.bar([0, 1, 2, 3], df.C, align='edge',width= -0.2)]

Just keep in mind, the width value for one group must be positive, and negative for the second one. Use align by edge as well.
You have to place the bar with the biggest values before the bar with the lowest values, and if you want the bars to appear stacked above one another rather than one in front of another, change df.B and df.D to df.B + df.A and df.D + df.C, respectively. If there's no apparent or consisting pattern, use the align by edge and width method with the one suggested by @piRSquared.
Another alternative would be to access each value from a green bar and compare it to the corresponding value from the red bar, and plot accordingly (too much unnecessary work in this one).

Answered By - Meher Béjaoui