What is the numpy.gradient() Method in Numpy?

Gradient is one of the most-used and sought-after topics in mathematics. In graphical terms, the gradient (also called slope) of a straight line demonstrates how steep a straight line is. In other words, it represents the change in the height of a line by the change in the horizontal distance of the line.

The gradient of a function, which is computed by taking the partial derivative of all the function's points, is the largest indicator of the function's increase or decrease in scientific terms.

NumPy.gradient() Method

The gradient is calculated using the numpy gradient() function by utilizing either the first or second-order correct one-sides (in either direction) differences at the boundaries and second-order accurate central differences in the interior locations.

To put simply, we identify the routes that cover the most sites in the quickest amount of time.

Consider that you are asked to run a lap in a jogging park, blindfolded, and you only know your present height and the distance you travel. It will take a lot of computations to complete the track, and by the end, you will find the best way to complete the track in the shortest amount of time. This is how the numpy gradient() function works.

Syntax

The syntax for numpy gradient() function is:

Parameters

The parameters for numpy gradient() function is:

• arr: The input array for which the gradient is to be found. It is a compulsory parameter.
• axis: It decides the direction to calculate the gradient of the input array. It's an optional parameter.
• edge_order: It is used concerning the boundaries aspect of the gradient. It is an optional parameter.

Return Type

The numpy gradient() function returns an N-dimensional array/list, where N is the size of the input(original) array. Each derivative shares the input array's form.

Examples

Here are some examples to solidify the concept of gradient():

Finding the gradient of a single array:

Output

Finding the gradient of multiple arrays:

Output

Finding the gradient for two-dimensional arrays:

Output

Finding the gradient for non-uniform arrays

Output

NumPy Diff and NumPy Gradient

The diff() function in NumPy is very similar to the gradient() function. This function is used to calculate the discrete difference along the given axis. If 'b' is the input array, the discrete difference is given by out[i]=x[i+1]-a[i].

While the diff() function gives the difference from the matrix slice, the numpy gradient() function returns the array of gradients along the provided dimensions. The numpy gradient() function creates a set of gradients of an array while preserving its original shape.

Output

Importance of NumPy.gradient() in Neural Networks

A neural network is an algorithm that uses a method that resembles how the human brain works to help us identify underlying links between a set of data. Gradient Descent is a concept that is used quite frequently when it comes to Neural Networks.

Gradient Descent is an optimization algorithm that is used for finding the local minimum of a differentiable function. It is used to minimize a cost function as far as possible. Using the numpy gradient() function helps us to generate gradients for the data points, which in turn helps us to find the local minimum of a function.