Folium是建立在Python生态系统的数据整理(Datawrangling)能力和Leaflet.js库的映射能力之上的开源库。用Python处理数据,然后用Folium将它在Leaflet地图上进行可视化。 概念 Folium能够将通过Python处理后的数据轻松地在交互式的Leaflet地图上进行可视化展示。它不单单可以在地图上展示数据的分布图,还可以使用Vincent/Vega在地图上加以标记。 这个开源库中有许多来自OpenStreetMap、MapQuest Open、MapQuestOpen Aerial、Mapbox和Stamen的内建地图元件,而且支持使用Mapbox或Cloudmade的API密钥来定制个性化的地图元件。Folium支持GeoJSON和TopoJSON两种文件格式的叠加,也可以将数据连接到这两种文件格式的叠加层,最后可使用color-brewer配色方案创建分布图。 安装 安装folium包 开始创建地图 创建底图,传入起始坐标到Folium地图中: importfolium map_osm= folium.Map(location=[45.5236, -122.6750]) #输入坐标 map_osm.create_map(path='osm.html') Folium默认使用OpenStreetMap元件,但是Stamen Terrain, Stamen Toner, Mapbox Bright 和MapboxControl空间元件是内置的: #输入位置,tiles,缩放比例 stamen =folium.Map(location=[45.5236, -122.6750], tiles='Stamen Toner',zoom_start=13) stamen.create_map(path='stamen_toner.html')#保存图片 Folium也支持Cloudmade 和 Mapbox的个性化定制地图元件,只需简单地传入API_key : custom =folium.Map(location=[45.5236, -122.6750], tiles='Mapbox', API_key='wrobstory.map-12345678') 最后,Folium支持传入任何与Leaflet.js兼容的个性化地图元件: tileset= r'http://{s}.tiles.yourtiles.com/{z}/{x}/{y}.png' map =folium.Map(location=[45.372, -121.6972], zoom_start=12, tiles=tileset, attr='My DataAttribution') 地图标记 Folium支持多种标记类型的绘制,下面从一个简单的Leaflet类型的位置标记弹出文本开始: map_1 =folium.Map(location=[45.372, -121.6972], zoom_start=12, tiles='Stamen Terrain') map_1.simple_marker([45.3288,-121.6625], popup='Mt. Hood Meadows')#文字标记 map_1.simple_marker([45.3311,-121.7113], popup='Timberline Lodge') map_1.create_map(path='mthood.html') Folium支持多种颜色和标记图标类型: map_1 =folium.Map(location=[45.372, -121.6972], zoom_start=12,tiles='Stamen Terrain') map_1.simple_marker([45.3288,-121.6625], popup='Mt. Hood Meadows',marker_icon='cloud') #标记图标类型为云 map_1.simple_marker([45.3311,-121.7113], popup='Timberline Lodge',marker_color='green') #标记颜色为绿色 map_1.simple_marker([45.3300,-121.6823], popup='Some OtherLocation',marker_color='red',marker_icon='info-sign') #标记颜色为红色,标记图标为“info-sign”) map_1.create_map(path='iconTest.html') Folium也支持使用个性化的尺寸和颜色进行圆形标记: map_2 =folium.Map(location=[45.5236, -122.6750], tiles='Stamen Toner', zoom_start=13) map_2.simple_marker(location=[45.5244,-122.6699], popup='The Waterfront') 简单树叶类型标记 map_2.circle_marker(location=[45.5215,-122.6261], radius=500, popup='Laurelhurst Park',line_color='#3186cc', fill_color='#3186cc')#圆形标记 map_2.create_map(path='portland.html') Folium有一个简便的功能可以使经/纬度悬浮于地图上: map_3 =folium.Map(location=[46.1991, -122.1889], tiles='Stamen Terrain',zoom_start=13) map_3.lat_lng_popover map_3.create_map(path='sthelens.html') Click-for-marker功能允许标记动态放置: map_4 =folium.Map(location=[46.8527, -121.7649], tiles='Stamen Terrain',zoom_start=13) map_4.simple_marker(location=[46.8354,-121.7325], popup='Camp Muir') map_4.click_for_marker(popup='Waypoint') map_4.create_map(path='mtrainier.html') Folium也支持来自Leaflet-DVF的Polygon(多边形)标记集: map_5 =folium.Map(location=[45.5236, -122.6750], zoom_start=13) map_5.polygon_marker(location=[45.5012,-122.6655], popup='Ross Island Bridge',fill_color='#132b5e', num_sides=3,radius=10)#三边形标记 map_5.polygon_marker(location=[45.5132,-122.6708], popup='Hawthorne Bridge',fill_color='#45647d', num_sides=4,radius=10)#四边形标记 map_5.polygon_marker(location=[45.5275,-122.6692], popup='Steel Bridge',fill_color='#769d96', num_sides=6, radius=10)#四边形标记 map_5.polygon_marker(location=[45.5318,-122.6745], popup='Broadway Bridge',fill_color='#769d96', num_sides=8,radius=10) #八边形标记 map_5.create_map(path='bridges.html') Vincent/Vega标记 Folium能够使用vincent 进行任何类型标记,并悬浮在地图上。 buoy_map= folium.Map(location=[46.3014, -123.7390], zoom_start=7, tiles='StamenTerrain') buoy_map.polygon_marker(location=[47.3489,-124.708], fill_color='#43d9de',radius=12, popup=(vis1, 'vis1.json')) buoy_map.polygon_marker(location=[44.639,-124.5339], fill_color='#43d9de',radius=12, popup=(vis2, 'vis2.json')) buoy_map.polygon_marker(location=[46.216,-124.1280], fill_color='#43d9de',radius=12, popup=(vis3, 'vis3.json')) GeoJSON/TopoJSON层叠加 GeoJSON 和TopoJSON层都可以导入到地图,不同的层可以在同一张地图上可视化出来: geo_path= r'data/antarctic_ice_edge.json' topo_path= r'data/antarctic_ice_shelf_topo.json' ice_map= folium.Map(location=[-59.1759, -11.6016],tiles='Mapbox Bright', zoom_start=2) ice_map.geo_json(geo_path=geo_path)#导入geoJson层 ice_map.geo_json(geo_path=topo_path,topojson='objects.antarctic_ice_shelf')#导入Toposon层 ice_map.create_map(path='ice_map.html') 分布图 Folium允许PandasDataFrames/Series类型和Geo/TopoJSON类型之间数据转换。Color Brewer 颜色方案也是内建在这个库,可以直接导入快速可视化不同的组合: importfolium importpandas as pd state_geo= r'data/us-states.json'#地理位置文件 state_unemployment= r'data/US_Unemployment_Oct2012.csv'#美国失业率文件 state_data= pd.read_csv(state_unemployment) #LetFolium determine the scale map =folium.Map(location=[48, -102], zoom_start=3) map.geo_json(geo_path=state_geo,data=state_data, columns=['State', 'Unemployment'], key_on='feature.id', fill_color='YlGn',fill_opacity=0.7, line_opacity=0.2, legend_name='Unemployment Rate(%)') map.create_map(path='us_states.html') 基于D3阈值尺度,Folium在右上方创建图例,通过分位数创建最佳猜测值,导入设定的阈值很简单: map.geo_json(geo_path=state_geo,data=state_data, columns=['State', 'Unemployment'], threshold_scale=[5, 6, 7, 8, 9,10], key_on='feature.id', fill_color='BuPu',fill_opacity=0.7, line_opacity=0.5, legend_name='Unemployment Rate(%)', reset=True) map.create_map(path='us_states.html') 通过Pandas DataFrame进行数据处理,可以快速可视化不同的数据集。下面的例子中,df DataFrame包含6列不同的经济数据,我们将在下面可视化一部分数据: 2011年就业率分布图 map_1 =folium.Map(location=[48, -102], zoom_start=3) map_1.geo_json(geo_path=county_geo,data_out='data1.json', data=df, columns=['GEO_ID','Employed_2011'],key_on='feature.id', fill_color='YlOrRd',fill_opacity=0.7, line_opacity=0.3, topojson='objects.us_counties_20m')#2011就业率分布图 map_1.create_map(path='map_1.html') 2011年失业率分布图 map_2 =folium.Map(location=[40, -99], zoom_start=4) map_2.geo_json(geo_path=county_geo,data_out='data2.json', data=df, columns=['GEO_ID','Unemployment_rate_2011'], key_on='feature.id', threshold_scale=[0, 5, 7, 9, 11,13], fill_color='YlGnBu', line_opacity=0.3, legend_name='Unemployment Rate2011 (%)', topojson='objects.us_counties_20m')#2011失业率分布图 map_2.create_map(path='map_2.html') 2011年中等家庭收入分布图 map_3 =folium.Map(location=[40, -99], zoom_start=4) map_3.geo_json(geo_path=county_geo,data_out='data3.json', data=df, columns=['GEO_ID','Median_Household_Income_2011'], key_on='feature.id', fill_color='PuRd',line_opacity=0.3, legend_name='Median Household Income2011 ($)', topojson='objects.us_counties_20m')#2011中等家庭收入分布图 map_3.create_map(path='map_3.html') 需要python教程+PDF电子书的小伙伴 |
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