Python is the main programming language of choice for the data science industry. This course will cover the key ideas of using Python.

Python Interview

Introduction

Python as a Programming Language

Python as Statistical Software

Python Packages

Why Python?

Data structures in Python attempt to be more intuitive and flexible than traditional data structures in other programming languages.

Basic Data Types

Iterables

Functions and Classes

Find the Missing Number

Find Bigrams

Merge Sorted Lists

Permutation Palindrome

Equivalent Index

Data Structures

As we said in the first section of this course, a major benefit of using Python for data science in comparison to other programming languages is the availability of a large number of useful packages that are distributed under a free license. 

numpy

scipy

matplotlib

pandas

sklearn

Over 100 Dollars

Good Grades and Favorite Colors

Generate Normal Distribution

Random Seed Function

Complete Addresses

Common DS Packages

Let's try some hard Python questions that you would see in tougher data science interviews and many machine learning interviews.

Max Width

Scrambled Tickets

Bernoulli Sample

Sum to N

Check Normality

Pool Matching

Python Questions: Hard

Other than SQL, Python is the most common language used in data science, due to its easy-to-read syntax and its robust collection of packages created specifically for data scientists. 

Learn the basics of Python and how to approach coding and problem solving

You’re given a dataframe of students named <code>students_df</code>:

<code>students_df</code> table

<table>
<thead>
<tr>
<th>name</th>
<th>age</th>
<th>favorite_color</th>
<th>grade</th>
</tr>
</thead>

<tbody>
<tr>
<td>Tim Voss</td>
<td>19</td>
<td>red</td>
<td>91</td>
</tr>

<tr>
<td>Nicole Johnson</td>
<td>20</td>
<td>yellow</td>
<td>95</td>
</tr>

<tr>
<td>Elsa Williams</td>
<td>21</td>
<td>green</td>
<td>82</td>
</tr>

<tr>
<td>John James</td>
<td>20</td>
<td>blue</td>
<td>75</td>
</tr>

<tr>
<td>Catherine Jones</td>
<td>23</td>
<td>green</td>
<td>93</td>
</tr>
</tbody>
</table>
Write a function named <code>grades_colors</code> to select only the rows where the student’s favorite color is green or red and their grade is above 90.

Example:

Input:

<pre tabindex="0" class="chroma"><code>import pandas as pd

students = {&#34;name&#34; : [&#34;Tim Voss&#34;, &#34;Nicole Johnson&#34;, &#34;Elsa Williams&#34;, &#34;John James&#34;, &#34;Catherine Jones&#34;], &#34;age&#34; : [19, 20, 21, 20, 23], &#34;favorite_color&#34; : [&#34;red&#34;, &#34;yellow&#34;, &#34;green&#34;, &#34;blue&#34;, &#34;green&#34;], &#34;grade&#34; : [91, 95, 82, 75, 93]}

students_df = pd.DataFrame(students)
</code></pre>

Output:

<pre tabindex="0" class="chroma"><code>def grades_colors(students_df) -&gt;
</code></pre>

<table>
<thead>
<tr>
<th>name</th>
<th>age</th>
<th>favorite_color</th>
<th>grade</th>
</tr>
</thead>

<tbody>
<tr>
<td>Tim Voss</td>
<td>19</td>
<td>red</td>
<td>91</td>
</tr>

<tr>
<td>Catherine Jones</td>
<td>23</td>
<td>green</td>
<td>93</td>
</tr>
</tbody>
</table>

Write a function to select only the rows where the student's favorite color is green or red and their grade is above 90.

Python Interview

Good Grades and Favorite Colors
Go to question details page

50%

Python Interview

Good Grades and Favorite ColorsGo to question details page

50%

Good Grades and Favorite Colors
Go to question details page