scipy 函数插值、求导和积分― ―数学中的几点乐趣

qhhrdooz 于 2022-12-13 发布在其他

关注(0)|答案(1)|浏览(129)

我有一个问题。我有三个列表。list_umf是x值，list_kf是y值，而list_kfm也是y值。kfm是kf的积分。这些值是我代码的输出。
为了证明kfm是kf的积分，我想计算kfm的导数，它应该与kf相同。但每次重新计算kfm（list_kf_re）都只是101.0。
我的代码有什么问题？

import numpy as np
from scipy import integrate, interpolate
from scipy.misc import derivative as deriv
import matplotlib.pyplot as plt

list_kfm = [15.348748494618041, 26.240336614039776, 37.76846357985518, 49.80068952374503, 62.25356792292074, 75.0692188764684, 88.20491343740369, 101.6276911997135,
    115.31128207665246, 129.2342114999071, 143.37856687640036, 157.72915825067278, 172.27292637703843, 186.9985127198004, 201.89593919604192, 216.95636451973587]
list_kf = [168.08871431597626, 179.78615963605742, 188.728883379148, 196.0371678709251, 202.25334207341422, 207.68364358717665, 212.51893919883966, 216.88670040685466,
    220.87653440371076, 224.55397301446894, 227.96847485999652, 231.15833919688876, 234.1538643061246, 236.97945558527186, 239.65507793294745, 242.19728380107006]
list_umf = [0.1, 0.15000000000000002, 0.20000000000000004, 0.25000000000000006, 0.30000000000000004, 0.3500000000000001, 0.40000000000000013, 0.45000000000000007,
    0.5000000000000001, 0.5500000000000002, 0.6000000000000002, 0.6500000000000001, 0.7000000000000002, 0.7500000000000002, 0.8000000000000002, 0.8500000000000002]

f = interpolate.interp1d(
    list_umf, list_kfm, bounds_error=False, fill_value=(15, 217))

list_kf_re = [deriv(f, x) for x in list_umf]

plt.plot(list_umf, list_kfm, label='kfm')
plt.plot(list_umf, list_kf, label='kf')
plt.plot(list_umf, list_kf_re, label='kfre')

print(list_kf_re)
print(list_kf)

scipy

来源：https://stackoverflow.com/questions/74775404/interpolate-derivate-and-integrate-a-function-some-math-fun

1条答案

按热度按时间

ckx4rj1h1#

使用UnivariateSpline创建一个插值器，以后可以应用积分或微分函数（请参见this post）
样品：

import numpy as np
#from scipy import integrate, interpolate
from scipy.interpolate import UnivariateSpline as US, InterpolatedUnivariateSpline as IUS
#from scipy.misc import derivative as deriv
import matplotlib.pyplot as plt

list_kfm = [15.348748494618041, 26.240336614039776, 37.76846357985518, 49.80068952374503, 62.25356792292074, 75.0692188764684, 88.20491343740369, 101.6276911997135,
    115.31128207665246, 129.2342114999071, 143.37856687640036, 157.72915825067278, 172.27292637703843, 186.9985127198004, 201.89593919604192, 216.95636451973587]
list_kf = [168.08871431597626, 179.78615963605742, 188.728883379148, 196.0371678709251, 202.25334207341422, 207.68364358717665, 212.51893919883966, 216.88670040685466,
    220.87653440371076, 224.55397301446894, 227.96847485999652, 231.15833919688876, 234.1538643061246, 236.97945558527186, 239.65507793294745, 242.19728380107006]
list_umf = [0.1, 0.15000000000000002, 0.20000000000000004, 0.25000000000000006, 0.30000000000000004, 0.3500000000000001, 0.40000000000000013, 0.45000000000000007,
    0.5000000000000001, 0.5500000000000002, 0.6000000000000002, 0.6500000000000001, 0.7000000000000002, 0.7500000000000002, 0.8000000000000002, 0.8500000000000002]

f = US(list_umf, list_kfm)

list_kf_re = [f.derivative()(x) for x in list_umf]

plt.plot(list_umf, list_kfm, label='kfm')
plt.plot(list_umf, list_kf, label='kf')
plt.plot(list_umf, list_kf_re, label='kfre')
plt.plot(list_umf, list_kf, 'o', label='kfre_2')

print(list_kf_re)
print(list_kf)

赞(0）回复(0）举报 2022-12-13

我来回答

scipy 函数插值、求导和积分― ―数学中的几点乐趣

1条答案

相关问题

热门标签

最新问答