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Copyright (C) 2019 Chris Havlin, https://chrishavlin.com

This program is free software: you can redistribute it and/or modify it under the terms of the GNU General Public License as published by the Free Software Foundation, either version 3 of the License, or (at your option) any later version.

This program is distributed in the hope that it will be useful but WITHOUT ANY WARRANTY; without even the implied warranty of MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the GNU General Public License for more details.

You should have received a copy of the GNU General Public License along with this program. If not, see http://www.gnu.org/licenses/.

DESCRIPTION

This is a collection of scripts for learning to work with shapefiles in python, assuming no previous knowledge (of either shapefiles or the python libraries used in manipulating them).

src/ includes a number of python scripts, tested with python

The documentation for pyshp is very useful: https://pypi.python.org/pypi/pyshp

REQUIREMENTS

• python (2.xx or 3.xx should work)
• general libraries: numpy, matplotlib, pandas
• for reading/writing shapefiles: pyshp or fiona (depending on script)
• for scripts with polygons: shapely, descartes

colorado_plateau.py uses a shapefile from Fenneman and Johnson (1946): see comments for where to download it.

CONTENTS

scripts in src/ include:

• basic_read_plot.py: reads a shapefile, plots outlines of geometry
• basic_readshp_plotpoly.py: reads a shapefile, plots geometry using polygons
• simple_polygons.py: plots several simple polygons
• read_shp_and_rcrd.py: reads a shapefile, plots geometry using polygons colored by record values. The record indexing is specific to the census.gov State Boundaries shapefile.
• colorado_plateau.py: reads the shapefile from Fenneman and Johnson (1946), pulls out Colorado Plateau shapes and generates a single shape for the full physiographic boundary of the Colorado Plateau.
• affine_expansion.py: reads a CSV of lat/lon coords for a polygon and scales the shape by specified amounts.
• contourf_to_shp.py: converts contourf levels into polygons, saves to shape file