解一元方程：
1 2 3 | from sympy import * x, a, b, c = symbols('x a b c') solve(a * x**2 + b * x + c, x) |
解多元方程：
1 2 3 4 5 6 7 8 9 10 11 12 13 14 15 16 17 18 19 20 21 22 23 24 25 26 27 28 29 30 31 | from sympy import * x, y, z = symbols('x y z') solve([y + x - 1, 3 * x + 2 * y - 5], [x, y]) limit(sin(x) / x, x, 0) simplify(sin(x)**2 + cos(x)**2) expand((x + 1)**2) factor(x**2 + 2*x + 1) collect(x*y + x - 3 + 2*x**2 - z*x**2 + x**3, x) trigsimp(cosh(x)**2 + sinh(x)**2) expand_trig(sin(x + y)) x, y = symbols('x y', positive=True) n = symbols('n', real=True) expand_log(log(x*y)) logcombine(n*log(x)) E**(I*pi)+1 expand(exp(I*x), complex=True) tmp = series(exp(I*x), x, 0, 10) pprint(tmp) re(tmp) series(sinh(x), x, 0, 10) integrate(x*sin(x), x) integrate(x*sin(x), (x, 0, 2*pi)) diff(x**2) r = symbols('r', positive=True) circle_area = 2 * integrate(sqrt(r**2-x**2), (x, -r, r)) circle_area.subs(r, x) |
求数值解
1 2 3 | s = solve(a * x**2 + b * x + c, x) val = s.evalf(subs = {a:1, b:2, c:1}) print(str(val)) |
Fourier,
from sympy import * from sympy.abc import x s = fourier_series(x**2, (x, -pi, pi)) s.truncate(4) |
refer to:
https://blog.csdn.net/shuangguo121/article/details/86611948
https://www.cnblogs.com/coshaho/p/9653460.html
https://baike.baidu.com/item/%E5%8F%8C%E6%9B%B2%E5%87%BD%E6%95%B0/8704306?fr=aladdin
https://www.cnblogs.com/FrostyForest/p/16660154.html