# How to Use the Scipy integrate.quad() Method in Python

Contents

In this article, you will learn how to use the Scipy integrate.quad() method in Python.

## Scipy integrate.quad() Method

The scipy.integrate.quad() method is a function from the scipy.integrate module that computes a definite integral of a given function over a specified interval. The integral is calculated using the Gauss-Kronrod quadrature algorithm, which is a widely used numerical integration method.

Here’s how to use scipy.integrate.quad() method in Python:

##### Import the necessary modules:

`import scipy.integrate as integrate`

##### Define the function you want to integrate:

The function should take a single argument (the variable of integration) and return a single value:

```
def integrand(x):
return x**2
```

##### Call the quad() method:

Call the quad() method with the integrand function and the limits of integration as arguments. The limits of integration should be specified as a tuple (lower limit, upper limit):

`result, error = integrate.quad(integrand, 0, 1)`

##### The quad() method returns two values:

The result of the integration and an estimate of the error in the result. You can assign these values to variables for later use:

`print(result, error)`

Putting it all together, here’s an example that integrates the function x^2 over the interval [0, 1]:

```
import scipy.integrate as integrate
def integrand(x):
return x**2
result, error = integrate.quad(integrand, 0, 1)
print(result, error)
```

The output should be 0.33333333333333337 3.700743415417189e-15, which is the result of the integration and an estimate of the error.