A Geospatial Python Package for Field Researchers

Owlet and EGF: Developed for Field Researchers

Owlet is a Python library for interacting with and mapping EGF files.

EGF, or Exact Geometry Format, is a file structure designed specifically for recording geo-data without traditional GIS software. An EGF file contains all of the necessary components required to define geospatial features— without overcomplicating it.

EGF File Example

Overview

An EGF file is comprised of three sections:

1. A Feature Type Declaration (point, line, polygon)
2. Attribute Headers
3. Features: attributes & coordinate sets

Example EFG file containing two placemarks:

PT



Park Name, City, Pond, Fountain



Post office Square, Boston, FALSE, TRUE
42.356243, -71.055631, 2



Boston Common, Boston, TRUE, TRUE
42.355465, -71.066412, 10

In an EGF file, each section / feature is separated by three blank lines and the file ends with a single blank line.

An EGF file is a '.txt' file renamed to '.egf'

Full EGF Documentation

How to Use Owlet

Install

Windows

>>> py -m pip install  owlet

MacOS / Linux

>>> pip3 install owlet

Reading an EGF file

import owlet

file_path = r"path/to/file/PostOfficeSquare.egf"

my_shape = owlet.egf_read(file_path)

Converting an EGF File to Other Formats

CSV

csv = my_shape.table()

GeoJSON

json = my_shape.geo_json()

EGF

egf = my_shape.egf()

Owlet in Use

Owlet Code Snippets

Visualizing an EGF

import owlet

# File path of EGF file
file_path = r"path/to/file/PostOfficeSquare.egf"

# Loading EGF into Owlet
my_shape = owlet.egf_read(file_path)

# Opening a preview with http://geojson.io
my_shape.geo_json(visualize=True)

Writing a GeoJSON file for use with GIS software

import owlet

# File path of EGF file
file_path = r"path/to/file/PostOfficeSquare.egf"

# Loading EGF into Owlet
my_shape = owlet.egf_read(file_path)

# Saving GeoJSON to a variable
json = my_shape.geo_json()

# Full path of file to create- including file extension ".json"
json_path = r"path/to/file/PostOfficeSquare.json"

# Writing GeoJSON to file
owlet.text_writer(json_path, json)

Converting EGF file to CSV for external filtering / manipulation

import owlet

# File path of EGF file
file_path = r"path/to/file/PostOfficeSquare.egf"

# Loading EGF into Owlet
my_shape = owlet.egf_read(file_path)

# Converting EGF into a table that can be wrtten to a '.csv' file
csv_data = myshape.table()

# Full path of file to create- including file extension ".csv"
csv_path = r"path/to/file/PostOfficeSquare.csv"

# Writing table to file
owlet.write_csv(csv_path, csv_data)

Loading CSV back into Owlet

# Full path of file to read
csv_path = r"path/to/file/PostOfficeSquare.csv"

geom_type = 'PT'  # Tells Owlet what type of feature to expect when reading csv

# Loading csv into Owlet
owlet.from_csv(geom_type, csv_path)

Owlet License: GNU GPLv3