Python中matplotlib模塊及柱狀圖的使用方法

import matplotlib.pyplot as plt
import numpy as np
 
def test4():
  names = ['電影1', '電影2', '電影3']
  real_num1 = [7548, 4013, 1673]
  real_num2 = [5453, 1840, 1080]
  real_num3 = [4348, 2345, 1890]
  x = np.arange(len(names))
  # 繪制柱形圖
  width = 0.3
  plt.bar(x, real_num1, alpha=0.5, width=width, label=names[0])
  plt.bar([i+width for i in x], real_num2, alpha=0.5, width=width, label=names[1])
  plt.bar([i+2*width for i in x], real_num3, alpha=0.5, width=width, label=names[2])
  # 正常顯示中文
  plt.rcParams["font.sans-serif"] = ["SimHei"]
  # 設(shè)置x坐標(biāo)軸的值
  x_label = ["第{}天".format(i+1) for i in x]
  # 讓x坐標(biāo)軸顯示在中間
  plt.xticks([i+width for i in x], x_label)
  # 添加ylabel
  plt.ylabel("票房數(shù)")
  # 添加圖例
  plt.legend()
  # 添加標(biāo)題
  plt.title("3天3部電影票房數(shù)")
  plt.show()
 
test4()

from mpl_toolkits.mplot3d import Axes3Dimport matplotlib.pyplot as pltimport numpy as np
 
def test5():
  # ax.plot_surface(X, Y, Z, rstride=1, cstride=1, cmap='rainbow') #繪面
  # 繪制3D曲面圖
  fig = plt.figure()
  ax = Axes3D(fig)
  # -4 到4 [-4, 4)，步長(zhǎng)為0.25
  X = np.arange(-4, 4, 0.25)
  Y = np.arange(-4, 4, 0.25)
  # meshgrid方法，你只需要構(gòu)造一個(gè)表示x軸上的坐標(biāo)的向量和一個(gè)表示y軸上的坐標(biāo)的向量;然后作為參數(shù)給到meshgrid(),該函數(shù)就會(huì)返回相應(yīng)維度的兩個(gè)矩陣;
  X, Y = np.meshgrid(X, Y)
  R = np.sqrt(X**2 + Y ** 2)
  Z = np.sin(R)
  ax.plot_surface(X, Y, Z, rstride=1, cstride=1, cmap="rainbow")
  plt.show()

import matplotlib.pyplot as plt
import numpy as np
def test6():
  # 繪制三維散點(diǎn)圖
  # ax.scatter(x[1000:4000],y[1000:4000],z[1000:4000],c='r') #繪點(diǎn)
  data = np.random.randint(0, 255, size=[40, 40, 40])
  x, y, z = data[0], data[1], data[2]
  # 創(chuàng)建一個(gè)三維的繪圖工程
  ax = plt.subplot(111, projection="3d")
  # 將數(shù)據(jù)點(diǎn)分成三部分畫，在顏色上有區(qū)分度
  ax.scatter(x[:10], y[:10], z[:10], c='y') # 繪制數(shù)據(jù)點(diǎn)
  ax.scatter(x[10:20], y[10:20], z[10:20], c='r')
  ax.scatter(x[30:40], y[30:40], z[30:40], c='g')
  # 坐標(biāo)軸
  ax.set_zlabel("Z")
  ax.set_ylabel("Y")
  ax.set_xlabel("X")
  plt.show()