Matplotlib - label each bin
Sure! To set the ticks, just, well... Set the ticks (see matplotlib.pyplot.xticks
or ax.set_xticks
). (Also, you don't need to manually set the facecolor of the patches. You can just pass in a keyword argument.)
For the rest, you'll need to do some slightly more fancy things with the labeling, but matplotlib makes it fairly easy.
As an example:
import matplotlib.pyplot as plt
import numpy as np
from matplotlib.ticker import FormatStrFormatter
data = np.random.randn(82)
fig, ax = plt.subplots()
counts, bins, patches = ax.hist(data, facecolor='yellow', edgecolor='gray')
# Set the ticks to be at the edges of the bins.
ax.set_xticks(bins)
# Set the xaxis's tick labels to be formatted with 1 decimal place...
ax.xaxis.set_major_formatter(FormatStrFormatter('%0.1f'))
# Change the colors of bars at the edges...
twentyfifth, seventyfifth = np.percentile(data, [25, 75])
for patch, rightside, leftside in zip(patches, bins[1:], bins[:-1]):
if rightside < twentyfifth:
patch.set_facecolor('green')
elif leftside > seventyfifth:
patch.set_facecolor('red')
# Label the raw counts and the percentages below the x-axis...
bin_centers = 0.5 * np.diff(bins) + bins[:-1]
for count, x in zip(counts, bin_centers):
# Label the raw counts
ax.annotate(str(count), xy=(x, 0), xycoords=('data', 'axes fraction'),
xytext=(0, -18), textcoords='offset points', va='top', ha='center')
# Label the percentages
percent = '%0.0f%%' % (100 * float(count) / counts.sum())
ax.annotate(percent, xy=(x, 0), xycoords=('data', 'axes fraction'),
xytext=(0, -32), textcoords='offset points', va='top', ha='center')
# Give ourselves some more room at the bottom of the plot
plt.subplots_adjust(bottom=0.15)
plt.show()
One thing I wanted to add to the plots in the histogram with "density = True" was the relative frequency values for each bin, search but I couldn't find a function that would do that. A solution I made follows as image:
The function:
def label_densityHist(ax, n, bins, x=4, y=0.01, r=2, **kwargs):
"""
Add labels,relative value of bin, to each bin in a density histogram .
:param ax: Object axe of matplotlib
The axis to plot.
:param n: list, array of int, float
The values of the histogram bins.
:param bins: list, array of int, float
The edges of the bins.
:param x: int, float
Related the x position of the bin labels. The higher, the lower the value on the x-axis.
Default: 4
:param y: int, float
Related the y position of the bin labels. The higher, the greater the value on the y-axis.
Default: 0.01
:param r: int
Number of decimal places.
Default: 2
:param **kwargs: Text properties in matplotlib
:return: None
Example
import matplotlib.pyplot as plt
import numpy as np
dados = np.random.randn(100)
axe = plt.gca()
n, bins, _ = axe.hist(x=dados, edgecolor='black')
label_densityHist(axe,n, bins)
plt.show()
Example:
import matplotlib.pyplot as plt
import numpy as np
dados = np.random.randn(100)
axe = plt.gca()
n, bins, _ = axe.hist(x=dados, edgecolor='black')
label_densityHist(axe,n, bins, x=6, fontsize='large')
plt.show()
Reference:
[1]https://matplotlib.org/3.1.1/api/text_api.html#matplotlib.text.Text
"""
k = []
# calculate the relative frequency of each bin
for i in range(0,len(n)):
k.append((bins[i+1]-bins[i])*n[i])
# rounded
k = around(k,r); #print(k)
# plot the label/text to each bin
for i in range(0, len(n)):
x_pos = (bins[i + 1] - bins[i]) / x + bins[i]
y_pos = n[i] + (n[i] * y)
label = str(k[i]) # relative frequency of each bin
ax.text(x_pos, y_pos, label, kwargs)