最近工作的原因，需要进行一些积分运算，通过一些搜索得知了SymPy，记录一下使用历程。

1. SymPy介绍

SymPy是关于Symbolic Mathematics的Python库，它旨在成为一个功能全面的计算机代数系统(CAS)，同时保持代码尽可能简单，以便易于理解和扩展。SymPy是完全使用Python所编写。

2. 积分计算

Integral(*args: Any, meijerg: Any = None, conds: str = 'piecewise', risch: Any = None, heurisch: Any = None, manual: Any = None, **kwargs: Any)

$https://latex.codecogs.com/svg.image?f = \int_{a}^{b} 3 * x + 1 dx$

x = symbols('x')

f = integrate(3 * x + 1, (x))
print(f)

如果积分的上下界已知，则求定积分值，假设a = 0，b = 1：

x = symbols('x')

f = integrate(3 * x + 1, (x, 0, 1)) 
print(f)

如果积分的下界已知，求上界，假设a = 0, 求b：

x = symbols('x')
b = symbols('b')

f = integrate(3 * x + 1, (x, 0, b))
ret = solve(f, b)
print(ret)

以些类推，可以只求下限，或同时求上下限。

$https://latex.codecogs.com/svg.image?f = \int_{a}^{b}\int_{c}^{d}e^{-x^2-y^2}{\mathrm{d}x}$

x = symbols('x')
y = symbols('y')

f1 = exp(- x ** 2 - y ** 2)
f = integral(f1, (x, 0, oo), (y, 0, oo))
print(f)

diff(f: Any, *symbols: Any, **kwargs: Any)

$https://latex.codecogs.com/svg.image?f = {\mathrm{d}^n}(cos(x))$

x = symbols('x')
n = 1

f = diff(cos(x), x, n)
print(f)

$https://latex.codecogs.com/svg.image?f = \frac{\partial^7 }{\partial x\partial y^2\partial z^2}e^{xyz}$

x, y, z = symbols('x y z')

f = diff(exp(x * y * z), x, 1, y, 2, z, 4)
print(f)

limit(e: Any, z: Any, z0: Any, dir: Any = "+")

$https://latex.codecogs.com/svg.image?f = \displaystyle \lim_{x \to x_0}\frac{sin(x)}{x}$

x = symbols('x')

f = limit(sin(x) / x, x, 0, '+')
print(f)

后续添加....

posted on 2022-03-22 14:05 汝熹阅读(257) 评论(0) 编辑收藏举报