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Jubaeir Islam
Jubaeir Islam

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Why Numpy is so important for Data Science?

What is Numpy?

NumPy is a Python library that is used for scientific computing. It is designed to work with large arrays of data, and provides functions for working with these arrays efficiently. It is an essential tool for working with data in Python, and is widely used in many different fields such as scientific research, machine learning, and data analysis.

Use Cases of Numpy

Data scientists use NumPy because it provides a number of convenient features for working with large arrays of data. For example, NumPy allows data scientists to perform mathematical operations on entire arrays of data, which is much more efficient than performing the same operations on individual data points. NumPy also provides tools for working with arrays of data that have missing or incomplete values, which is a common issue in many data sets. Additionally, NumPy is fast and efficient, which is important when working with large amounts of data. Overall, NumPy provides data scientists with a powerful and convenient set of tools for working with data in Python.

Python List vs Numpy Arrays

Data scientists use NumPy because it provides a number of convenient features for working with large arrays of data. For example, NumPy allows data scientists to perform mathematical operations on entire arrays of data, which is much more efficient than performing the same operations on individual data points. NumPy also provides tools for working with arrays of data that have missing or incomplete values, which is a common issue in many data sets. Additionally, NumPy is fast and efficient, which is important when working with large amounts of data. Overall, NumPy provides data scientists with a powerful and convenient set of tools for working with data in Python.

Python Lists vs Numpy Arrays

NumPy arrays and Python lists are similar in that they are both used to store collections of data. However, there are some key differences between the two. NumPy arrays are typically more efficient than Python lists for storing and manipulating large amounts of data. This is because NumPy arrays are stored in contiguous blocks of memory, which makes it more efficient to access and manipulate the data. In contrast, Python lists are stored in a more flexible way, which makes them more flexible but less efficient for working with large amounts of data. Additionally, NumPy provides a number of convenient functions for working with arrays, which makes it easier to perform mathematical operations on the data. Overall, NumPy arrays are more efficient and convenient for working with large amounts of data, and are the preferred choice for many data science applications.

Numpy in a nutshell

To use NumPy, you first need to import it into your Python environment using the import statement. For example, you can import NumPy using the following code:

import numpy as np
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Once you have imported NumPy, you can create arrays using the np.array() function. This function takes a list of numbers as input, and returns a NumPy array containing those numbers. For example, the following code creates a NumPy array containing the numbers 1, 2, and 3:

my_array = np.array([1, 2, 3])
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NumPy arrays support a wide range of mathematical operations, such as addition, subtraction, multiplication, and division. These operations can be performed on entire arrays at once, rather than on individual elements. For example, the following code adds two NumPy arrays together:

array1 = np.array([1, 2, 3])
array2 = np.array([4, 5, 6])

array3 = array1 + array2

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In this example, array3 will be equal to [5, 7, 9]. NumPy also provides a number of convenient functions for working with arrays, such as finding the minimum and maximum values, calculating the mean and standard deviation, and more.

Overall, NumPy is a powerful and convenient library for working with large arrays of data in Python. It is an essential tool for many data science applications, and is widely used in fields such as scientific research, machine learning, and data analysis.

Most used built-in functions for Numpy used by professionals

Some of the most commonly used built-in functions in NumPy include:

  • np.array(): This function is used to create NumPy arrays from a list of numbers.
  • np.zeros(): This function creates a new NumPy array filled with zeros.
  • np.ones(): This function creates a new NumPy array filled with ones.
  • np.full(): This function creates a new NumPy array filled with a specified value.
  • np.eye(): This function creates a new square NumPy array with the diagonal elements set to one and the rest set to zero.
  • np.linspace(): This function creates a new NumPy array with a specified number of evenly spaced elements between a start and end value.
  • np.random.random(): This function creates a new NumPy array with random values between 0 and 1.
  • np.mean(): This function calculates the mean of the elements in a NumPy array.
  • np.min(): This function calculates the minimum value of the elements in a NumPy array.
  • np.max(): This function calculates the maximum value of the elements in a NumPy array. These are just a few examples of the many built-in functions that NumPy provides. NumPy also offers many other functions for working with arrays, such as functions for sorting, reshaping, and concatenating arrays.

Summary

Data scientists use NumPy because it provides a number of convenient features for working with large arrays of data. For example, NumPy allows data scientists to perform mathematical operations on entire arrays of data, which is much more efficient than performing the same operations on individual data points. NumPy also provides tools for working with arrays of data that have missing or incomplete values, which is a common issue in many data sets. Additionally, NumPy is fast and efficient, which is important when working with large amounts of data. Overall, NumPy provides data scientists with a powerful and convenient set of tools for working with data in Python.

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