Numpy Clip Example

Numpy Clip Example

Numpy is a fundamental library for scientific computing in Python. It provides a high-performance multidimensional array object, and tools for working with these arrays. One of the useful functions provided by Numpy is clip(). This function is used to limit the values in an array to a specified range. In this article, we will explore the clip() function in detail, providing numerous examples to illustrate its use.

Introduction to Numpy Clip

The clip() function takes an array and bounds as its input and returns a new array where every element is clipped to the bounds provided. The syntax of the function is:

numpy.clip(a, a_min, a_max, out=None)
  • a is the array containing elements to clip.
  • a_min is the minimum value to clip to.
  • a_max is the maximum value to clip to.
  • out is an optional array in which to place the result.

If an element in the array a is smaller than a_min, it will be replaced with a_min. If an element in the array a is larger than a_max, it will be replaced with a_max.

Example 1: Basic Usage of Clip

import numpy as np

arr = np.array([1, 2, 3, 4, 5, 6, 7, 8, 9])
clipped_arr = np.clip(arr, 3, 7)
print(clipped_arr)

Output:

Numpy Clip Example

Example 2: Clipping 2D Arrays

import numpy as np

arr = np.array([[1, 2, 3], [4, 5, 6], [7, 8, 9]])
clipped_arr = np.clip(arr, 2, 8)
print(clipped_arr)

Output:

Numpy Clip Example

Example 3: Using Clip with Negative Bounds

import numpy as np

arr = np.array([-12, 0, 10, -5, 8, -1])
clipped_arr = np.clip(arr, -10, 10)
print(clipped_arr)

Output:

Numpy Clip Example

Example 4: Clipping with No Upper Bound

import numpy as np

arr = np.array([1, 2, 3, 4, 5, 6, 7, 8, 9])
clipped_arr = np.clip(arr, 3, None)
print(clipped_arr)

Output:

Numpy Clip Example

Example 5: Clipping with No Lower Bound

import numpy as np

arr = np.array([1, 2, 3, 4, 5, 6, 7, 8, 9])
clipped_arr = np.clip(arr, None, 7)
print(clipped_arr)

Output:

Numpy Clip Example

Example 6: Using Clip with Out Parameter

import numpy as np

arr = np.array([1, 2, 3, 4, 5, 6, 7, 8, 9])
out_arr = np.empty_like(arr)
np.clip(arr, 3, 7, out=out_arr)
print(out_arr)

Output:

Numpy Clip Example

Example 7: Clipping Multidimensional Array

import numpy as np

arr = np.random.randint(1, 100, (5, 5))
clipped_arr = np.clip(arr, 10, 90)
print(clipped_arr)

Output:

Numpy Clip Example

Example 8: Clipping with Scalars

import numpy as np

arr = np.array([1.1, 2.5, 3.8, 4.6, 5.9])
clipped_arr = np.clip(arr, 2.0, 5.0)
print(clipped_arr)

Output:

Numpy Clip Example

Example 9: Clipping with Different Minimum and Maximum for Each Element

import numpy as np

arr = np.array([1, 2, 3, 4, 5])
min_bounds = np.array([1, 1, 2, 2, 3])
max_bounds = np.array([3, 3, 4, 4, 5])
clipped_arr = np.clip(arr, min_bounds, max_bounds)
print(clipped_arr)

Output:

Numpy Clip Example

Example 10: Using Clip in a Real-world Scenario

import numpy as np

# Simulating sensor data that might have erroneous values
sensor_data = np.array([102, 99, 450, 130, 120, 110, 115, 500, 106, 109])
# Assuming sensor range should be between 100 and 150
corrected_data = np.clip(sensor_data, 100, 150)
print(corrected_data)

Output:

Numpy Clip Example

Numpy Clip Example Conclusion

The clip() function in Numpy is a powerful tool for managing data ranges in arrays. It ensures that all elements in an array adhere to specified minimum and maximum bounds. This can be particularly useful in data cleaning processes where certain values may be out of the expected range due to measurement errors or other anomalies. By using clip(), you can ensure that your data remains robust and reliable for analysis.