Crispo - Excel Challenge 28 2025

excel-challenges
weekly-exercises
Easy Sunday Excel Challenge
Published

July 13, 2025

Illustration for Crispo - Excel Challenge 28 2025

Challenge Description

Easy Sunday Excel Challenge

⭐ ⭐Group the product sales

Solutions

library(tidyverse)
library(readxl)

path = "files/2025-07-13/Challenge 39.xlsx"
input = read_excel(path, range = "B2:D11")
test  = read_excel(path, range = "H2:I11")

result = input %>%
  arrange(Product, Date) %>%
  mutate(Product = ifelse(row_number() > 1, NA_character_, Product), .by = Product) %>%
  select(-Date)

all.equal(result, test, check.attributes = FALSE) 
# > [1] TRUE

  • Logic:

    • Reads the workbook range needed for the challenge

    • Builds the intermediate helper columns that drive the final answer

  • Strengths:

    • The R solution stays compact and mirrors the workbook logic closely.

  • Areas for Improvement:

    • The code assumes the workbook layout and named ranges remain stable.

  • Gem:

    • The best part of the solution is choosing a tidy intermediate shape before producing the final answer.
import pandas as pd

path = "files/2025-07-13/Challenge 39.xlsx"
input = pd.read_excel(path, usecols="B:D", skiprows=1, nrows=10)
test = pd.read_excel(path, usecols="H:I", skiprows=1, nrows=10).rename(columns=lambda c: c.replace('.1', ''))

result = (
    input
    .sort_values(['Product', 'Date'])
    .assign(Product=lambda df: df['Product'].where(df.groupby('Product').cumcount() == 0))
    .drop(columns=['Date'])
    .reset_index(drop=True)
)

print(result.equals(test)) # True

  • Logic:

    • Reads the workbook range needed for the challenge

    • Aggregates or ranks values at the correct grouping level

    • Builds the intermediate helper columns that drive the final answer

  • Strengths:

    • The Python version keeps the same rule in a direct pandas-oriented workflow.

  • Areas for Improvement:

    • As with the R version, any workbook layout change would require small adjustments.

  • Gem:

    • The implementation stays close to the stated challenge instead of adding unnecessary complexity.

Difficulty Level

This task is easy to moderate:

  • The business rule is readable, but the workbook still needs a few careful transformation steps.