Identify Date with Highest Total kWh Consumption Using Pandas

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Q: What difficulty level is this coding question?

This is a medium difficulty Data Manipulation (SQL/Python) question, commonly asked during Onsite rounds at Amazon.

Q: What role is this question designed for?

This question is commonly asked for Data Scientist candidates at Amazon during technical interviews.

Question

meter_readings

+----------+------------+---------------+---------+
| meter_id | timestamp  | kwh_consumed  | city    |
+----------+------------+---------------+---------+
| 1001     | 2023-01-01 | 15.2          | Austin  |
| 1001     | 2023-01-02 | 18.0          | Austin  |
| 1002     | 2023-01-01 | 22.5          | Dallas  |
| 1002     | 2023-01-02 | 20.1          | Dallas  |
| 1003     | 2023-01-01 | 10.7          | Houston |
+----------+------------+---------------+---------+

##### Scenario

Analyst needs to summarize smart-meter readings for an operations report.

##### Question

Using pandas, aggregate total kwh_consumed for each date and return the date with the highest total consumption.

##### Hints

groupby on timestamp, sum, use idxmax or sort_values.

PracHub · Accepted Answer

This question evaluates proficiency in pandas-based data manipulation and time-series aggregation, specifically the competency to aggregate and summarize meter readings to identify peak consumption dates.

Quick Overview

Identify Date with Highest Total kWh Consumption Using Pandas