在 Numpy 多项式中获取值的问题

Question

import numpy as np
import matplotlib.pyplot as plt
from numpy.polynomial import Chebyshev as T
X=np.array([1,2,4,5,6,7,8,9,10,11,12,13])
data=np.array([2.312,4.563,6.765,7.897,12.456,7.568,6.543,3.453,6.654,9.678,11.453,19.567])
p=T.fit(X,data,6)
plt.plot(X,data)
plt.plot(*p.linspace(60))

我生成了一个数据，我正在使用 numpy 多项式切比雪夫对其进行拟合。切比雪夫正在拟合数据，但我不知道如何从此代码中获取拟合数据值？有什么方法可以得到拟合值还是我必须更改整个代码？

Answer 1

在代码的末尾，Chebyshev 数据结构 p 包含获得任何拟合值所需的内容。例如，表达式

list(zip(*p.linspace(60)))

给出 60 个点的列表，其中每个 x 坐标是 1 和 13 之间的值，这是您为 x 值指定的界限。对应的y值就是x值的拟合值。然后你可以选择你想要的点。

这是运行您的代码后该表达式的结果：

[(1.0, 2.541204853676799),
 (1.2033898305084745, 2.808340815346975),
 (1.4067796610169492, 3.0743429556868413),
 (1.6101694915254239, 3.348688496878723),
 (1.8135593220338984, 3.637978305373278),
 (2.016949152542373, 3.9462679999194794),
 (2.2203389830508478, 4.27538454719654),
 (2.4237288135593222, 4.625228345047772),
 (2.6271186440677967, 4.994060793316362),
 (2.830508474576271, 5.3787773522831195),
 (3.0338983050847457, 5.775166088706113),
 (3.2372881355932206, 6.178151709462269),
 (3.440677966101695, 6.582025082790894),
 (3.6440677966101696, 6.980658247139146),
 (3.8474576271186445, 7.367704907609403),
 (4.050847457627119, 7.736786420008617),
 (4.254237288135593, 8.081663262499552),
 (4.4576271186440675, 8.396391994853994),
 (4.661016949152542, 8.675467705307872),
 (4.864406779661017, 8.913951945018319),
 (5.067796610169491, 9.107586150122668),
 (5.271186440677966, 9.252890551399389),
 (5.474576271186441, 9.347248571530947),
 (5.677966101694915, 9.388976709968594),
 (5.88135593220339, 9.37737991539911),
 (6.084745762711865, 9.312792445813466),
 (6.288135593220339, 9.196604216177416),
 (6.491525423728814, 9.031272633704036),
 (6.694915254237289, 8.820319920728197),
 (6.898305084745763, 8.568315925182945),
 (7.101694915254238, 8.280846418677859),
 (7.305084745762712, 7.964466882179304),
 (7.508474576271187, 7.626641779292636),
 (7.711864406779662, 7.275669317146346),
 (7.915254237288136, 6.920591694878116),
 (8.11864406779661, 6.5710908397228325),
 (8.322033898305085, 6.237369630702523),
 (8.52542372881356, 5.930018609918223),
 (8.728813559322035, 5.6598681814437874),
 (8.932203389830509, 5.437826297821619),
 (9.135593220338983, 5.274701634160355),
 (9.338983050847459, 5.1810122498344615),
 (9.542372881355933, 5.166779737785785),
 (9.745762711864407, 5.241308861427015),
 (9.949152542372882, 5.412952679147101),
 (10.152542372881356, 5.68886315641859),
 (10.35593220338983, 6.074727265506907),
 (10.559322033898306, 6.574488572781565),
 (10.76271186440678, 7.190054313629292),
 (10.966101694915254, 7.920987954969137),
 (11.16949152542373, 8.764187245369472),
 (11.372881355932204, 9.713547752766893),
 (11.576271186440678, 10.75961188978718),
 (11.779661016949154, 11.889203426668058),
 (11.983050847457628, 13.08504749178393),
 (12.186440677966102, 14.325376059772596),
 (12.389830508474578, 15.583518927263885),
 (12.593220338983052, 16.827480176210102),
 (12.796610169491526, 18.019500124818624),
 (13.0, 19.115602766086262)]

在 Numpy 多项式中获取值的问题

Problem in getting values in Numpy Polynomial

python

numpy

curve-fitting

polynomials