回答編集履歴
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answer
CHANGED
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@@ -53,4 +53,38 @@
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plt.show()
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```
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## 追記
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```python
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import matplotlib.pyplot as plt
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import numpy as np
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from sympy import *
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init_printing()
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x = Symbol('x')
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c, k = 1, 3
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z = -(c * x**2 / (1 + (1 - (1 + k) * c**2 * x**2)**0.5))
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prime_z = Derivative(z, x).doit()
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a = Symbol('a')
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z_a = z.subs(x, a) # f(a)
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prime_z_a = prime_z.subs(x, a) # f'(a)
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tangent = prime_z_a * (x - a) + z_a # 点 (a, f(a)) の接線
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normal = (-1 / prime_z_a) * (x - a) + z_a # 点 (a, f(a)) の法線
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theta = deg(atan(-1 / prime_z_a)) # 法線の角度
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```
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```
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xs = np.arange(0.1, 6.28, 0.1)
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thetas = np.array([complex(theta.subs(a, t)) for t in xs])
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# 保存
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np.savetxt("points.csv", np.c_[xs, thetas.real, thetas.imag], delimiter=",")
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# 読み込み
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xs, real, imag = np.loadtxt("points.csv", delimiter=",", unpack=True)
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thetas = real + 1j * imag
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```
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