# Python - How To Calculate the Slope in Python

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In Mathematics, a slope of a given line is a value that computes its steepness. It also helps in characterizing the direction of a given line. The scope of a line can also be calculated using the Python programming language.

This article will demonstrate the different methods available to calculate the slope of a given line in Python.

## Use the User-Defined Function to Calculate the Slope of a Given Line in Python

The mathematical formula for the slope of a given line is shown below.

``m = (y2-y1)/(x2-x1) ``

We can create a user-defined function that implements this given formula for a given line.

The following code uses a user-defined function `slopee` to calculate the slope of a given line in Python.

``def slopee(x1,y1,x2,y2):     x = (y2 - y1) / (x2 - x1)     return x  print(slopee(4,5,8,10)) ``

The code above provides the following output.

``1.25 ``

The function in the code above uses the general formula for the line’s slope and then returns its value.

## Use the `SciPy` Module to Calculate the Slope of a Given Line in Python

`SciPy`, an abbreviation for `Scientific Python`, is a free-to-use and open-source library utilized to do technical and scientific computing of data in Python. Additionally, `SciPy` is heavily dependent on the `NumPy` library. Apart from `NumPy`, `SciPy` contains a lot more modules used for stats, linear algebra, image processing, and optimization.

Here, we will use one such function: the `linregress()` function utilized to compute the linear least-squares regression for two given one-dimensional arrays of the same length. You can find the line’s slope using the `linregress()` function if we define the `x` and `y` coordinates as arrays.

The following code uses the `linregress()` method of the `SciPy` module to calculate the slope of a given line in Python.

``from scipy.stats import linregress x = [4, 8] y = [5, 10] slope, intercept, r_value, p_value, std_err = linregress(x, y) print(slope) ``

The code above provides the following output.

``1.25 ``

The slope of the line is returned in a `float` datatype.

## Use the `NumPy` Module to Calculate the Slope of a Given Line in Python

`NumPy`, an abbreviation for `Numerical Python`, is a library provided by Python, which deals with arrays and gives functions for operating on these arrays.

The `np.polyfit()` function, contained within the `NumPy` library, can be utilized to find and return the slope and intercept of the given particular line with the set of coordinates of a line defined as arrays.

The following code uses the `np.polyfit()` function to calculate the slope of a given line in Python.

``import numpy as np x = [4, 8] y = [5, 10] slope, intercept = np.polyfit(x,y,1) print(slope) ``

The code above provides the following output.

``1.2499999999999993 ``