在Python中使用 Matplotlib 进行插入排序的 3D 可视化

先决条件：插入排序，Matplotlib 简介

通过分析和比较为比较和交换元素而发生的操作数量，可视化算法可以更容易地理解它们。算法的 3D 可视化不太常见，为此我们将使用 matplotlib 绘制条形图并对其进行动画处理以表示数组的元素。

方法：

我们将生成一个包含随机元素的数组。
该算法将在该数组上调用，并且出于可视化目的，将使用 yield 语句而不是 return 语句。
在比较和交换之后，我们将产生数组的当前状态。因此该算法将返回一个生成器对象。
Matplotlib 动画将用于可视化数组的比较和交换。
然后我们将绘制图形，它将返回一个 Poly3dCollection 对象，使用该对象将完成进一步的动画。

下面是实现。

Python3

# import the modules
import matplotlib.pyplot as plt
from matplotlib.animation import FuncAnimation
from mpl_toolkits.mplot3d import axes3d
import matplotlib as mp
import numpy as np
import random
  
  
# Array size
n = 11
  
# insertion sort algorithm
def insertionsort(a):
    for j in range(1, len(a)):
        key = a[j]
        i = j-1
          
        while(i >= 0 and a[i] > key):
            a[i+1] = a[i]
            i -= 1
            yield a
        a[i+1] = key
          
        yield a
  
# method to plot graph
def showGraph(n):
    
    # for random unique values
    a = [i for i in range(1, n+1)]
    random.shuffle(a)
    datasetName = 'Random'
    algoName = 'Insertion Sort'
      
    # generator object returned by the function
    generator = insertionsort(a)
  
    # the style of the graph
    plt.style.use('fivethirtyeight')
  
    # set bar colors
    data_normalizer = mp.colors.Normalize()
    color_map = mp.colors.LinearSegmentedColormap(
        "my_map",
        {
            "red": [(0, 1.0, 1.0),
                    (1.0, .5, .5)],
            "green": [(0, 0.5, 0.5),
                      (1.0, 0, 0)],
            "blue": [(0, 0.50, 0.5),
                     (1.0, 0, 0)]
        }
    )
  
    # plot the array
    fig = plt.figure()
    ax = fig.add_subplot(projection='3d')
      
    # the z values and position of the bars
    z = np.zeros(n)
    dx = np.ones(n)
    dy = np.ones(n)
    dz = [i for i in range(len(a))]
      
    # plot 3d bars
    rects = ax.bar3d(range(len(a)), a, z, dx, dy, dz,
                     color=color_map(data_normalizer(range(n))))
    ax.set_xlim(0, len(a))
    ax.set_ylim(0, int(1.1*len(a)))
    ax.set_title("ALGORITHM : "+algoName+"\n"+"DATA SET : "+datasetName,
                 fontdict={'fontsize': 13, 
                           'fontweight': 'medium', 
                           'color': '#E4365D'})
      
    # 2D text placed on the upper left 
    # based on the axes fraction
    text = ax.text2D(0.1, 0.95, "", 
                     horizontalalignment='center',
                     verticalalignment='center', 
                     transform=ax.transAxes,
                     color="#E4365D")
    iteration = [0]
  
    # function for animating
    def animate(A, rects, iteration):
        
        # to clear the bars from the 
        # Poly3DCollection object
        ax.collections.clear()
        ax.bar3d(range(len(a)), A, z, dx, dy, dz,
                 color=color_map(data_normalizer(range(n))))
        iteration[0] += 1
        text.set_text("iterations : {}".format(iteration[0]))
  
    anim = FuncAnimation(fig, func=animate,
                         fargs=(rects, iteration),
                         frames=generator, interval=50,
                         repeat=False)
    plt.show()
  
# Driver Code
showGraph(n)

输出：