Bairros de João Pessoa#

import warnings
warnings.filterwarnings('ignore')

import pandas as pd
import geopandas as gpd
import matplotlib.pyplot as plt
from matplotlib.offsetbox import AnchoredText

Lendo de geodata-jp#

bairros = gpd.read_file('https://raw.githubusercontent.com/paulovitorweb/geodata-jp/main/data/bairros.geojson')

bairros.info()

<class 'geopandas.geodataframe.GeoDataFrame'>
RangeIndex: 64 entries, 0 to 63
Data columns (total 7 columns):
 #   Column     Non-Null Count  Dtype   
---  ------     --------------  -----   
 0   cod        64 non-null     object  
 1   nome       64 non-null     object  
 2   perimetro  64 non-null     float64 
 3   area       64 non-null     float64 
 4   hectares   64 non-null     float64 
 5   densidade  9 non-null      object  
 6   geometry   64 non-null     geometry
dtypes: float64(3), geometry(1), object(3)
memory usage: 3.6+ KB

bairros.head()

	cod	nome	perimetro	area	hectares	densidade	geometry
0	24	ERNESTO GEISEL	6650.895993	1.905707e+06	190.570736	None	POLYGON ((-34.86412 -7.17066, -34.86447 -7.170...
1	11	BESSA	6362.909869	2.040910e+06	204.091004	0,000000000	POLYGON ((-34.84627 -7.07684, -34.84493 -7.076...
2	02	AEROCLUBE	6436.704571	2.058472e+06	205.847186	0,000000000	POLYGON ((-34.84435 -7.09790, -34.84342 -7.097...
3	35	JARDIM OCEANIA	7344.368535	2.280272e+06	228.027235	0,000000000	POLYGON ((-34.83775 -7.09747, -34.83331 -7.097...
4	38	MANAÍRA	6610.028055	2.299794e+06	229.979426	0,000000000	POLYGON ((-34.83043 -7.11329, -34.82384 -7.110...

Excluindo alguns campos#

bairros = bairros.drop(columns=['perimetro', 'area', 'hectares', 'densidade'])
bairros.head()

	cod	nome	geometry
0	24	ERNESTO GEISEL	POLYGON ((-34.86412 -7.17066, -34.86447 -7.170...
1	11	BESSA	POLYGON ((-34.84627 -7.07684, -34.84493 -7.076...
2	02	AEROCLUBE	POLYGON ((-34.84435 -7.09790, -34.84342 -7.097...
3	35	JARDIM OCEANIA	POLYGON ((-34.83775 -7.09747, -34.83331 -7.097...
4	38	MANAÍRA	POLYGON ((-34.83043 -7.11329, -34.82384 -7.110...

Transformando para coordenadas métricas#

bairros = bairros.to_crs('EPSG:31985')
bairros.crs

<Projected CRS: EPSG:31985>
Name: SIRGAS 2000 / UTM zone 25S
Axis Info [cartesian]:
- E[east]: Easting (metre)
- N[north]: Northing (metre)
Area of Use:
- name: Brazil - between 36°W and 30°W, northern and southern hemispheres, onshore and offshore.
- bounds: (-36.0, -23.8, -29.99, 4.19)
Coordinate Operation:
- name: UTM zone 25S
- method: Transverse Mercator
Datum: Sistema de Referencia Geocentrico para las AmericaS 2000
- Ellipsoid: GRS 1980
- Prime Meridian: Greenwich

Calculando área dos bairros#

bairros['area_km2'] = bairros['geometry'].area / 1000000
bairros.head()

	cod	nome	geometry	area_km2
0	24	ERNESTO GEISEL	POLYGON ((294146.208 9206966.635, 294107.367 9...	1.905748
1	11	BESSA	POLYGON ((296077.112 9217351.507, 296224.360 9...	2.040906
2	02	AEROCLUBE	POLYGON ((296297.729 9215023.713, 296400.444 9...	2.059346
3	35	JARDIM OCEANIA	POLYGON ((297027.067 9215073.395, 297518.007 9...	2.278178
4	38	MANAÍRA	POLYGON ((297843.051 9213327.092, 298569.251 9...	2.302670

Plotando gráficos#

bairros.sort_values(by='area_km2')[-20:].plot.barh(x='nome', y='area_km2', figsize=(6,6))

<AxesSubplot:ylabel='nome'>

../../_images/geodata-jp-bairros-example_14_1.png

Plotando mapas#

def _insert_title(title, ax):
    at = AnchoredText(title, prop={'size':11}, frameon=True, loc='upper left')
    at.patch.set_boxstyle('square,pad=0.1')
    ax.add_artist(at)

def plot(bairro_nome):
    fig, ax = plt.subplots(1, 1, figsize=(5,5))
    _insert_title(bairro_nome, ax)
    bairros.plot(ax=ax, alpha=0.3, zorder=1)
    bairros[bairros['nome'] == bairro_nome].plot(ax=ax, alpha=0.9, edgecolor='k', zorder=2)

plot('CRISTO REDENTOR')

../../_images/geodata-jp-bairros-example_16_0.png

Adicionando anotação ao mapa#

def _insert_data(data, ax):
    x, y, arrow_length = 0.025, 0.89, 0.03
    ax.annotate(data, xy=(x, y), xytext=(x, y-arrow_length),
                ha='left', va='center', fontsize=10,
                xycoords=ax.transAxes)

def plot(bairro_nome):
    mask = bairros['nome'] == bairro_nome
    fig, ax = plt.subplots(1, 1, figsize=(5,5))
    _insert_title(bairro_nome, ax)
    bairro = bairros[mask]
    area = round(float(bairro.iloc[0]['area_km2']), 1)
    data = 'Área: ' + str(area) + ' km²'
    _insert_data(data, ax)
    bairros.plot(ax=ax, alpha=0.3, zorder=1)
    bairro.plot(ax=ax, alpha=0.9, edgecolor='k', zorder=2)

plot('CRISTO REDENTOR')