# Data Science Project on Area and Population

In this project we’ll use the size of points to indicate the area and populations of California cities. We would like a legend that specifies the scale of the sizes of the points, and we’ll accomplish this by plotting some labeled data with no entries.

```import pandas as pd
```# extracting the data we ar interested in
latitude, longitude = cities["latd"], cities["longd"]
population, area = cities["population_total"], cities["area_total_km2"]```
```# to scatter the points, using size and color but without label
import numpy as np
import matplotlib.pyplot as plt
import seaborn
seaborn.set()
plt.scatter(longitude, latitude, label=None, c=np.log10(population),
cmap='viridis', s=area, linewidth=0, alpha=0.5)
plt.axis(aspect='equal')
plt.xlabel('Longitude')
plt.ylabel('Longitude')
plt.colorbar(label='log\$_{10}\$(population)')
plt.clim(3, 7)
# now we will craete a legend, we will plot empty lists with the desired size and label
for area in [100, 300, 500]:
plt.scatter([], [], c='k', alpha=0.3, s=area, label=str(area) + 'km\$^2\$')
plt.legend(scatterpoints=1, frameon=False, labelspacing=1, title='City Areas')
plt.title("Area and Population of California Cities")
plt.show()```
##### Aman Kharwal

I'm a writer and data scientist on a mission to educate others about the incredible power of data📈.

Articles: 1501

1. #### Work on Data Science Projects | Data Science | Machine Learning | Python

[…] Data Science Project on Area and Population […]

2. #### Maverick

Small correction – Both axes are labeled Longitude. X-Axis must be labeled Latitude

• #### Aman Kharwal

Thanks for letting us know, keep visiting us.

3. #### Upendra Parwaz

How we get data used in this project.