# How to calculate definite integral in Python

Calculating definite integrals is a fundamental operation in calculus and numerical analysis. Python, with its powerful libraries, provides an efficient way to calculate these integrals, particularly using the SciPy library.

## Installing SciPy

Before calculating integrals, ensure that the SciPy library is installed in your Python environment. You can install it using the pip command:

``pip install scipy``

## Importing Required Function

From SciPy’s integrate module, import the quad function:

``from scipy.integrate import quad``

## Defining the Integrand Function

Define your integrand function to be integrated. For example, to integrate \(f(x) = x^2\):

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

## Calculating the Definite Integral

Use the quad function to calculate the definite integral by providing the integrand, lower limit, and upper limit. For instance, to calculate the integral of \(f(x) = x^2\) from 0 to 1:

``````
result, error = quad(integrand, 0, 1)
print("Integral result:", result)
print("Estimated error:", error)
``````

## Understanding the Output

The quad function returns two values: the calculated integral and an estimate of the absolute error. This error estimate is important for understanding the accuracy of the integral calculation.

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