难以使用 oop python 的 numpy 数组

Question

ValueError：x 和 y 必须具有相同的第一维，但具有形状 (50,) 和 (0,)。 foor 循环实例的值未存储在方法 init

中

import numpy as np
import matplotlib.pyplot as plt

class inter():


    def __init__(self):

        self.x = np.array([0, 20, 40, 60, 80, 100], float)
        self.y = np.array([20.0, 48.6, 61.6, 71.2, 74.8, 75.2], float)
        self.xplt = np.linspace(self.x[0], self.x[-1])
        self.yplt = np.array([], float)
        self.yp = 0


   def loop(self):

      for xp in self.xplt:
         for xi, yi in zip(self.x, self.y):
            self.yp += yi * np.prod((xp - self.x[self.x != xi]) / (xi - self.x[self.x != xi]))
         self.yplt = np.append(self.yplt, self.yp)


      return self.yplt

  def draw(self):

     plt.plot(self.xplt, self.yplt)
     plt.show()

int = inter()

int.draw()

Answer 1

我想你忘记打电话了：int.loop()

它对我有用：在 int.draw() 之前调用 int.loop() 或在 __init__()

中调用 self.loop()

import numpy as np
import matplotlib.pyplot as plt

class inter():


    def __init__(self):

        self.x = np.array([0, 20, 40, 60, 80, 100], float)
        self.y = np.array([20.0, 48.6, 61.6, 71.2, 74.8, 75.2], float)
        self.xplt = np.linspace(self.x[0], self.x[-1])
        self.yplt = np.array([], float)
        self.yp = 0

        self.loop()

    def loop(self):

        for xp in self.xplt:
            for xi, yi in zip(self.x, self.y):
                self.yp += yi * np.prod((xp - self.x[self.x != xi]) / (xi - self.x[self.x != xi]))
            self.yplt = np.append(self.yplt, self.yp)


        return self.yplt

    def draw(self):

        plt.plot(self.xplt, self.yplt)
        plt.show()

int = inter()

int.draw()

难以使用 oop python 的 numpy 数组

Difficult with numpy array using oop python

python

arrays

oop

matplotlib

numpy-ndarray