将自定义功能与sympy集成

Question

Is it possible to integrate custom function using sympy?

I want something like this:

def func(x, y):
    return something_with(x, y)

res = integrate(func, (y, x-2, 3), (x, 1, 2))

Is it possible?

Answer 1

You can integrate some functions with sympy's integrate . Suppose you had the function (one variable to make it simpler)

def my_func(x):
    return x**2 + x + 1

Then you could integrate it with

x = Symbol('x')
integrate(my_func(x), (x, a, b))

Although only limited mathematical functions are likely to work.

If you only care about the numerical answer, you could try scipy 's integrate.quad() (or scipy.integrate.dblquad() ) which will do numerical integration, and can tackle a broader set of functions within a small error.

scipy.integrate.quad(my_func, a, b)