15 to 30 random questions in 15 to 30 minutes, by the level you choose: arrays, broadcasting, loc/iloc, missing data, groupby, merge, dates. After you submit you get your score, your strong and weak topics, and the right answer with an explanation for every question.
Want to revise first? Read the Pandas and NumPy interview questions and answers.
The test covers 12 topics across three levels. Each attempt picks 15 to 30 questions at random, by the level you choose, so every attempt is different.
One question from each level, the way they appear in the test. A new set comes on the 1st of every month. Try it, then open the answer.
import pandas as pd
s = pd.Series([10, 20, 30, 40, 50], index=list('abcde'))
total = s.loc['b':'d'].sum()Answer: 90. Label slices with loc include both ends, so s.loc['b':'d'] keeps b, c and d (20, 30 and 40) and total is 90. Position slices with iloc exclude the stop, which is why 50 (only b and c) is the tempting wrong answer.
import numpy as np
a = np.array([5, -2, 8, -1])
a[a < 0] = 0
total = a.sum()Answer: 13. Assigning through a boolean mask writes into a itself, replacing only the negative values with 0. a becomes 5, 0, 8, 0, so total is 13. Unlike b = a[a < 0], which makes a copy, a[mask] = value changes the original array.
import numpy as np
a = np.zeros(3)
b = np.ones((2, 1))
a += bAnswer: It raises ValueError, because the (2, 3) result cannot be stored in a. a + b would broadcast to (2, 3), but an in-place operator must write into the existing array, whose shape is (3,), so NumPy raises ValueError about a non-broadcastable output operand. Use a = a + b to create a new array instead.
Take the full Pandas and NumPy mock test: 15 to 30 questions and 15 to 30 minutes, by level.
A question counts as right only when you pick exactly the right option, or all the right options where it says so; a question left blank counts as wrong. Your score is the share of the test's questions you got right (15 to 30, by level). The result also scores every topic, so you know what to revise before the interview.
Yes. The Pandas and NumPy mock test is free. You need a free CoreHRx Jobs account to start it, so your score and the topics to work on are saved.
It depends on the level: Fresher has 15 questions in 15 minutes, Intermediate has 20 questions in 20 minutes, Experienced has 30 questions in 30 minutes. They are multiple-choice questions picked at random from a larger bank of Pandas and NumPy questions at your level, so every attempt is different.
The questions cover GroupBy and Aggregation, apply and Performance, Merge, Join and Concat, Missing Data, NumPy Arrays and dtypes, Broadcasting and Vectorization, loc and iloc, Views and Copies, Indexing and Slicing, Series and DataFrames, Dates and Time Series, Reshaping and Pivoting. Your result shows how you did in each topic.
Fresher if you are a student or have less than a year of experience, Intermediate for 1 to 5 years at work, and Experienced for 5 years or more.
Only your best Pandas and NumPy score, and only when it is 60% or more. It shows on the job applications you send on CoreHRx. Lower scores stay private.
Yes, up to 10 tests a day. Each attempt picks questions you have not seen recently first.