Python NumPy - Practice Exercises, Questions and Solutions

Example Questions on NumPy Array

• Create an empty and 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
• Remove rows in Numpy array that contains non-numeric values
• Remove single-dimensional entries from shape of an array
• Find number of occurrences of a sequence
• Find most frequent value
• Combining a one and a two-dimensional
• Build an array of all combinations of two NumPy arrays
• Add a border around a NumPy array
• Compare two NumPy arrays
• Check whether specified values are present in NumPy array
• Get 2D diagonals of a 3D array
• Flatten a Matrix
• Flatten a 2d array into 1d array
• Move axes of an array to new positions
• Interchange two axes of an array
• Fibonacci Series using Binet Formula
• Counts number of non-zero values
• Count number of elements along a given axis
• Trim leading and/or trailing zeros from a 1-D array
• Change data type of given numpy array
• Reverse a numpy array
• Make a NumPy array read-only

Coding Problems

• Sum of All Elements in a Numpy Array
• Maximum Element in a Numpy Array
• Mean of a Numpy Array
• Reshape a Numpy Array
• Standard Deviation
• Element-wise Exponentiation
• Array Concatenation
• Reverse Rows of a 2D Array
• Diagonal Elements in an Array
• 3D Array from a List of Lists
• Accessing Element in a 3D Array
• Maximum Element along Each Axses in a 3D Array
• Slice a 3D Array
• Flatten a 3D Array

Example Questions on NumPy Matrix

• Maximum value from given matrix
• Minimum value from given matrix
• Find number of rows and columns of a given matrix
• Select elements from a given matrix
• Find sum of values in a matrix
• Calculate sum of the diagonal elements
• Adding and Subtracting Matrices
• Ways to add row/columns
• Matrix Multiplication
• Get eigen values of a matrix
• Calculate determinant of a matrix
• Inverse a matrix using NumPy
• Count frequency of unique values
• Multiply matrices of complex numbers
• Outer product of two given vectors
• Calculate inner, outer and cross products of matrices and vectors
• Compute covariance matrix of two given
• Convert covariance matrix to correlation matrix
• Compute Kronecker product of two mulitdimension
• Convert matrix into a list

Coding Problems

• Matrix Multiplication
• Transpose of a Matrix

Example Questions on NumPy Indexing

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

Example Questions on NumPy Linear Algebra

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

Coding Problem

• Linear Algebra

Example Questions on NumPy Random

• Create a Numpy array with random values
• Choose elements from the list with different probability
• Get weighted random choice
• Generate Random Numbers From Uniform Distribution
• Get Random Elements from 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

• Get indices of sorted array
• Finding k smallest values
• Get n-largest values of an array
• Sort values in a matrix
• Filter out integers from float numpy array
• Find indices into a sorted array

Coding Problems

• Sorting an Array
• Searching in 2D Array
• Sorting Array by Each Column

Questions on NumPy Mathematics

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

Questions on NumPy Statistics

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

Questions on Polynomial

• Define a polynomial function
• Add one polynomial to another
• Subtract one polynomial to another
• Multiply a polynomial to another
• Divide a polynomial to another
• Find roots of the polynomials
• Evaluate a 2-D polynomial series on Cartesian product
• Evaluate a 3-D polynomial series on Cartesian product

Questions on NumPy Strings

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

More Questions on NumPy

• Different ways to convert a dictionary to a NumPy array
• 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
• Convert an image to NumPy array and save it to CSV file
• Save a NumPy array to a text file
• Load data from a text file
• Plot line graph from NumPy array
• Create Histogram using NumPy