Restaurant performance

Introducing a No Smoking Day for the terrace (on request). Which day would be best?

Importing libraries and packages

# Mathematical operations and data manipulation
import numpy as np

# Plotting
import matplotlib.pyplot as plt
import seaborn as sns

# Warnings
import warnings

warnings.filterwarnings("ignore")

%matplotlib inline

Set paths

# Path to datasets directory
data_path = "./datasets"
# Path to assets directory (for saving results to)
assets_path = "./assets"

Loading dataset

dataset = sns.load_dataset("tips")

Exploring dataset

# Shape of the dataset
print("Shape of the dataset: ", dataset.shape)
# Head
dataset

Shape of the dataset:  (244, 7)

	total_bill	tip	sex	smoker	day	time	size
0	16.99	1.01	Female	No	Sun	Dinner	2
1	10.34	1.66	Male	No	Sun	Dinner	3
2	21.01	3.50	Male	No	Sun	Dinner	3
3	23.68	3.31	Male	No	Sun	Dinner	2
4	24.59	3.61	Female	No	Sun	Dinner	4
...	...	...	...	...	...	...	...
239	29.03	5.92	Male	No	Sat	Dinner	3
240	27.18	2.00	Female	Yes	Sat	Dinner	2
241	22.67	2.00	Male	Yes	Sat	Dinner	2
242	17.82	1.75	Male	No	Sat	Dinner	2
243	18.78	3.00	Female	No	Thur	Dinner	2

244 rows × 7 columns

Feature engineering

# Create a matrix where the elements contain the sum of the total bills
# for each day and are split by smokers/non-smokers:
days = ["Thur", "Fri", "Sat", "Sun"]
days_range = np.arange(len(days))
smoker = ["Yes", "No"]

bills_by_days = [dataset[dataset["day"] == day] for day in days]
bills_by_days_smoker = [
    [bills_by_days[day][bills_by_days[day]["smoker"] == s] for s in smoker]
    for day in days_range
]
total_by_days_smoker = [
    [
        bills_by_days_smoker[day][s]["total_bill"].sum()
        for s in range(len(smoker))
    ]
    for day in days_range
]
totals = np.asarray(total_by_days_smoker)
totals

array([[ 326.24,  770.09],
       [ 252.2 ,   73.68],
       [ 893.62,  884.78],
       [ 458.28, 1168.88]])

Visualisation

# Create figure
plt.figure(figsize=(10, 5), dpi=300)
# Create stacked bar plot
plt.bar(days_range, totals[:, 0], label="Smoker")
plt.bar(days_range, totals[:, 1], bottom=totals[:, 0], label="Non-smoker")
# Add legend
plt.legend()
# Add labels and title
plt.xticks(days_range)
ax = plt.gca()
ax.set_xticklabels(days)
ax.yaxis.grid()
plt.ylabel("Daily total sales in Euro")
plt.title("Restaurant performance")
# Show plot
plt.show()

Sunday and Thursday :)