Python NumPy – Practice Exercises, Questions, and Solutions

Python NumPy is a general-purpose array processing package. It provides fast and versatile n-dimensional arrays and tools for working with these arrays. It provides various computing tools such as comprehensive mathematical functions, random number generator and it’s easy to use syntax makes it highly accessible and productive for programmers from any background.

This NumPy exercise will help the learners to get a better understanding of NumPy arrays. This practice page consists of a huge set of NumPy programs like NumPy array, Matrix, handling indexing in NumPy, working with Mathematics. Statistics and all sort of frequently encountered problems.

Questions on NumPy Array

• How to create an empty and a full NumPy array?
• Create a Numpy array filled with all zeros
• Create a Numpy array filled with all ones
• Check whether a Numpy array contains a specified row
• How to Remove rows in Numpy array that contains non-numeric values?
• Remove single-dimensional entries from the shape of an array
• Find the number of occurrences of a sequence in a NumPy array
• Find the most frequent value in a NumPy array
• Combining a one and a two-dimensional NumPy Array
• How to build an array of all combinations of two NumPy arrays?
• How to add a border around a NumPy array?
• How to compare two NumPy arrays?
• How to check whether specified values are present in NumPy array?
• How to get all 2D diagonals of a 3D NumPy array?
• Flatten a Matrix in Python using NumPy
• Flatten a 2d numpy array into 1d array
• Move axes of an array to new positions
• Interchange two axes of an array
• NumPy – Fibonacci Series using Binet Formula
• Counts the number of non-zero values in the array
• Count the number of elements along a given axis
• Trim the leading and/or trailing zeros from a 1-D array
• Change data type of given numpy array
• Reverse a numpy array
• How to make a NumPy array read-only?

Questions on NumPy Matrix

• Get the maximum value from given matrix
• Get the minimum value from given matrix
• Find the number of rows and columns of a given matrix using NumPy
• Select the elements from a given matrix
• Find the sum of values in a matrix
• Calculate the sum of the diagonal elements of a NumPy array
• Adding and Subtracting Matrices in Python
• Ways to add row/columns in numpy array
• Matrix Multiplication in NumPy
• Get the eigen values of a matrix
• How to Calculate the determinant of a matrix using NumPy?
• How to inverse a matrix using NumPy
• How to count the frequency of unique values in NumPy array?
• Multiply matrices of complex numbers using NumPy in Python
• Compute the outer product of two given vectors using NumPy in Python
• Calculate inner, outer, and cross products of matrices and vectors using NumPy
• Compute the covariance matrix of two given NumPy arrays
• Convert covariance matrix to correlation matrix using Python
• Compute the Kronecker product of two mulitdimension NumPy arrays
• Convert the matrix into a list

Questions on NumPy Indexing

• Replace NumPy array elements that doesn’t satisfy the given condition
• Return the indices of elements where the given condition is satisfied
• Replace NaN values with average of columns
• Replace negative value with zero in numpy array
• How to get values of an NumPy array at certain index positions?
• Find indices of elements equal to zero in a NumPy array
• How to Remove columns in Numpy array that contains non-numeric values?
• How to access different rows of a multidimensional NumPy array?
• Get row numbers of NumPy array having element larger than X
• Get filled the diagonals of NumPy array
• Check elements present in the NumPy array
• Combined array index by index

Questions on NumPy Linear Algebra

• Find a matrix or vector norm using NumPy
• Calculate the QR decomposition of a given matrix using NumPy
• Compute the condition number of a given matrix using NumPy
• Compute the eigenvalues and right eigenvectors of a given square array using NumPy?
• Calculate the Euclidean distance using NumPy

Questions on NumPy Random

• Create a Numpy array with random values
• How to choose elements from the list with different probability using NumPy?
• How to get weighted random choice in Python?
• Generate Random Numbers From The Uniform Distribution using NumPy
• Get Random Elements form geometric distribution
• Get Random elements from Laplace distribution
• Return a Matrix of random values from a uniform distribution
• Return a Matrix of random values from a Gaussian distribution

Questions on NumPy Sorting and Searching

• How to get the indices of the sorted array using NumPy in Python?
• Finding the k smallest values of a NumPy array
• How to get the n-largest values of an array using NumPy?
• Sort the values in a matrix
• Filter out integers from float numpy array
• Find the indices into a sorted array

Questions on NumPy Mathematics

• How to get element-wise true division of an array using Numpy?
• How to calculate the element-wise absolute value of NumPy array?
• Compute the negative of the NumPy array
• Multiply 2d numpy array corresponding to 1d array
• Computes the inner product of two arrays
• Compute the nth percentile of the NumPy array
• Calculate the n-th order discrete difference along the given axis
• Calculate the sum of all columns in a 2D NumPy array
• Calculate average values of two given NumPy arrays
• How to compute numerical negative value for all elements in a given NumPy array?
• How to get the floor, ceiling and truncated values of the elements of a numpy array?
• How to round elements of the NumPy array to the nearest integer?
• Find the round off the values of the given matrix
• Determine the positive square-root of an array
• Evaluate Einstein’s summation convention of two multidimensional NumPy arrays

Questions on NumPy Statistics

• Compute the median of the flattened NumPy array
• Find Mean of a List of Numpy Array
• Calculate the mean of array ignoring the NaN value
• Get the mean value from given matrix
• Compute the variance of the NumPy array
• Compute the standard deviation of the NumPy array
• Compute pearson product-moment correlation coefficients of two given NumPy arrays
• Calculate the mean across dimension in a 2D NumPy array
• Calculate the average, variance and standard deviation in Python using NumPy
• Describe a NumPy Array in Python

Questions on Polynomial

• Define a polynomial function
• How to add one polynomial to another using NumPy in Python?
• How to subtract one polynomial to another using NumPy in Python?
• How to multiply a polynomial to another using NumPy in Python?
• How to divide a polynomial to another using NumPy in Python?
• Find the roots of the polynomials using NumPy
• Evaluate a 2-D polynomial series on the Cartesian product
• Evaluate a 3-D polynomial series on the Cartesian product

Questions on NumPy Strings

• Repeat all the elements of a NumPy array of strings
• How to split the element of a given NumPy array with spaces?
• How to insert a space between characters of all the elements of a given NumPy array?
• Find the length of each string element in the Numpy array
• Swap the case of an array of string
• Change the case to uppercase of elements of an array
• Change the case to lowercase of elements of an array
• Join String by a separator
• Check if two same shaped string arrayss one by one
• Count the number of substrings in an array
• Find the lowest index of the substring in an array
• Get the boolean array when values end with a particular character

More Questions on NumPy

• Different ways to convert a Python dictionary to a NumPy array
• How to convert a list and tuple into NumPy arrays?
• Ways to convert array of strings to array of floats
• Convert a NumPy array into a csv file
• How to Convert an image to NumPy array and save it to CSV file using Python?
• How to save a NumPy array to a text file?
• Load data from a text file
• Plot line graph from NumPy array
• Create Histogram using NumPy