Python中的 Matplotlib.axes.Axes.hist()

Matplotlib是Python中的一个库，它是 NumPy 库的数值数学扩展。 Axes 类包含大部分图形元素：Axis、Tick、Line2D、Text、Polygon 等，并设置坐标系。 Axes 的实例通过回调属性支持回调。

matplotlib.axes.Axes.hist()函数

matplotlib 库的 axes 模块中的Axes.hist()函数用于绘制直方图。

Syntax: Axes.hist(self, x, bins=None, range=None, density=None, weights=None, cumulative=False, bottom=None, histtype=’bar’, align=’mid’, orientation=’vertical’, rwidth=None, log=False, color=None, label=None, stacked=False, normed=None, *, data=None, **kwargs)

Parameters: This method accept the following parameters that are described below:

x : This parameter are the sequence of data.
bins : This parameter is an optional parameter and it contains the integer or sequence or string.
range : This parameter is an optional parameter and it the lower and upper range of the bins.
density : This parameter is an optional parameter and it contains the boolean values.
weights : This parameter is an optional parameter and it is an array of weights, of the same shape as x.
bottom : This parameter is the location of the bottom baseline of each bin.
histtype : This parameter is an optional parameter and it is used to draw type of histogram. {‘bar’, ‘barstacked’, ‘step’, ‘stepfilled’}
align : This parameter is an optional parameter and it controls how the histogram is plotted. {‘left’, ‘mid’, ‘right’}
rwidth : This parameter is an optional parameter and it is a relative width of the bars as a fraction of the bin width
log : This parameter is an optional parameter and it is used to set histogram axis to a log scale
color : This parameter is an optional parameter and it is a color spec or sequence of color specs, one per dataset.
label : This parameter is an optional parameter and it is a string, or sequence of strings to match multiple datasets.
normed : This parameter is an optional parameter and it contains the boolean values.It uses the density keyword argument instead.

Returns: This returns the following:

n :This returns the values of the histogram bins.
bins :This returns the edges of the bins.
patches :This returns the list of individual patches used to create the histogram.

编程需要懂一点英语

下面的示例说明了 matplotlib.axes 中的 matplotlib.axes.Axes.hexbin()函数：

示例 1：

# Implementation of matplotlib function
import matplotlib
import numpy as np
import matplotlib.pyplot as plt
  
np.random.seed(10**7)
mu = 121  
sigma = 21
x = mu + sigma * np.random.randn(1000)
  
num_bins = 100
fig, ax = plt.subplots()
  
n, bins, patches = ax.hist(x, num_bins,
                           density = 1, 
                           color ='green', 
                           alpha = 0.7)
  
y = ((1 / (np.sqrt(2 * np.pi) * sigma)) *
     np.exp(-0.5 * (1 / sigma * (bins - mu))**2))
ax.plot(bins, y, '--', color ='black')
ax.set_xlabel('X-Axis')
ax.set_ylabel('Y-Axis')
  
ax.set_title('matplotlib.axes.Axes.hist() Example')
plt.show()

输出：

示例 2：

# Implementation of matplotlib function
import matplotlib
import numpy as np
import matplotlib.pyplot as plt
  
np.random.seed(10**7)
n_bins = 20
x = np.random.randn(10000, 3)
  
fig, [(ax0, ax1), (ax2, ax3)] = plt.subplots(nrows = 2,
                                             ncols = 2)
  
  
colors = ['green', 'blue', 'lime']
  
ax0.hist(x, n_bins, density = True, 
         histtype ='bar',
         color = colors, 
         label = colors)
  
ax0.legend(prop ={'size': 10})
  
ax1.hist(x, n_bins, density = True,
         histtype ='barstacked',
         stacked = True, 
         color = colors)
  
ax2.hist(x, n_bins, histtype ='step',
         stacked = True,
         fill = False, 
         color = colors)
  
x_multi = [np.random.randn(n) for n in [100000,
                                        80000,
                                        1000]]
  
ax3.hist(x_multi, n_bins, 
         histtype ='stepfilled',
         color = colors)
  
plt.show()

输出：