python - matplotlib advanced bar plot

Question

I need to recreate a chart similar to the one below created in Excel. I was hoping to use matplotlib, but can't seem to find any examples or reference for how to do a chart like this. I need to have bars colored based on a performance threshold, and also display the threshold. Can anyone point me in the right direction? I do need to be able to do this with Python, though. plot example

Paul H Paul H · Accepted Answer · 2013-11-12T01:42:44

I gotta run, but here's something to get you started:

import numpy as np
import matplotlib
matplotlib.rcParams['text.usetex'] = False
import matplotlib.pyplot as plt
import pandas

df = pandas.DataFrame(np.random.uniform(size=37)*100, columns=['A'])
threshold = 75
fig, ax = plt.subplots(figsize=(8,3))

good = df['A'][df['A'] >= threshold]
bad = df['A'][df['A'] < threshold]

ax.bar(left=good.index, height=good, align='center', color='ForestGreen', zorder=5)
ax.bar(left=bad.index, height=bad, align='center', color='Firebrick', zorder=5)

ax.axhline(y=threshold, linewidth=2, color='ForestGreen', zorder=0)

ax.set_xticks(df.index)
ax.set_xlim(left=df.index[0]-0.75, right=df.index[-1]+0.75)

def annotateBars(row, ax=ax):
    if row['A'] < 20:
        color = 'black'
        vertalign = 'bottom'
        vertpad = 2
    else:
        color = 'white'
        vertalign = 'top'
        vertpad = -2

    ax.text(row.name, row['A'] + vertpad, "{:.1f}%".format(row['A']),
            zorder=10, rotation=90, color=color,
            horizontalalignment='center',
            verticalalignment=vertalign,
            fontsize=8, weight='heavy')

junk = df.apply(annotateBars, ax=ax, axis=1)

And that gives me: annotated bar plot

python - matplotlib advanced bar plot

1 Answers