But how to find such id, starting from a comuna's name? Let's first create a usefull function to convert our 'shapefile' format on a more commun Pandas dataframe format: def read_shapefile(sf): """ Read a shapefile into a Pandas dataframe with a 'coords' column holding the geometry information. In the last example, I previously knew that Santiago'’ id was '25'. Converting shapefile data on Pandas dataframe Note that you can apply what will be describe on this tutorial to any shapfile. We can see that some data changed and most importantly, the name of the 'comuna', that is now, 'SANTIAGO'. This means that exist 52 shapes on our shape files, what make sense, once the Santiago Metropolitan Region has 52 "comunas" as shown at below map (do not worry, before the end of this article, you will learn how to create a map like this one, directly from your data):īut, Let’ s end sightseeing and take a look on Santiago's comuna data structure (id: 25): sf.records() Let's check how many different "shapes" were imported by our function shp.Reader: len(sf.shapes()) Shp_path = “./Comunas_RM_Mapas_Vectoriales/Comuna.shp” sf = shp.Reader(shp_path) On INE (Chilean National Institute of Statistics), is possible to download a group of shapefiles related with maps, created for the last national 2017 census : On this tutorial, we will work with maps related to the cities ("Comunas") that together, make the Santiago Metropolitan Region. Important that all other files as 'name.shx', ' name.dbf', etc., must be at same folder. Opening a Vector MapĪs described on 1., a vector map is a group of several files, with name.shp being the main one, where the geographic features are saved. Initializing vizualization set sns.set(style=”whitegrid”, palette=”pastel”, color_codes=True) (“figure”, figsize=(10,6))Īnd if you are using a Jupyter Notebook: %matplotlib inline 4. Importing and initializing main Python libraries import numpy as np import pandas as pd import shapefile as shp import matplotlib.pyplot as plt import seaborn as sns To Install pyshp, execute below instruction in your Terminal: pip install pyshp 3. The Shapefile format is a popular Geographic Information System vector data format created by Esri. The Python Shapefile Library (pyshp) provides read and write support for the Esri Shapefile format. Installing Python Shapefile Library (PyShp) lyr file is often included as it contains specifications of how to display the data (colour, labelling, etc) in ArcGIS software.įor more info see wikipedia 2. Although not part of the Esri shapefile standard, the. prj file which describes the coordinate system and projection information used. There are also several optional files in the shapefile format. dbf - attribute format columnar attributes for each shape, in dBase IV format. shx - shape index format a positional index of the feature geometry to allow seeking forwards and backwards quickly. shp - shape format the feature geometry itself. The shapefile is in fact a grouping of several files formatted to represent different aspects of geodata: Broadly speaking these are a bit like OSM’s tags. Each geometry has a set of associated attributes. In OpenStreetMap terms these can be considered as ‘ nodes’, ‘ ways’ and ‘ closed ways’, respectively. Developed and regulated by Esri as a (mostly) open specification, the shapefile format spatially describes geometries as either ‘points’, ‘polylines’, or ‘polygons’.
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