karta 0.2.2

A tidy Python package for geospatial computation

Karta is a Leatherman for geographic analyses. Karta provides an interface for solving problems in Python/Python3 that works nicely with existing packages. It provides simple and clean vector and raster data types, a small selection of analysis functions, and the ability to read and write several useful formats.

Goals of Karta include providing a simple, lightweight, and fast set of tools useful for everyday spatial analysis, as well as a flexible set of abstractions upon which to build more advanced routines. Karta should be considered a work in progress.

##CONTENTS AT A GLANCE

• vector

  • guppy: Vector geometry classes (e.g. Point, Multipoint, Line, Polygon)

  • gpx: GPX class for parsing and constructing GPX eXchange files

  • geojson: Classes and functions for reading and writing GeoJSON

  • vtk: XML-based VTK interface

  • shp_funcs: Shapefile-to-guppy conversions through _pyshp_ interface

  • stats: Basic geostatistical functions

  • xyfile: ASCII table functions

• raster

  • grid: Basic Grid types, including StructuredGrid and RegularGrid

  • raster: General purpose raster functions

  • aaigrid: Grid subclass specifically for reading, writing, and manipulating ESRI ASCII grids

  • flow: Stream flow functions

  • streamline: Streamline calculation

• tests : unit tests

##FORMATS

Karta provides a basic working interface to several of common file formats. Currently partially-supported are:

• vector

  • ASCII tables (XYZ) (r,w)

  • GeoJSON (r,w)

  • GPS eXchange (GPX) (r,w)

  • VTK (w)

  • ESRI Shapefiles via pyshp (r,w)

• raster

  • ESRI ASCII Grid (r,w)

  • USGS DEM (WIP)

## INSTALLATION

The easiest way to install is to use pip.

cd karta/ pip install .

## DEPENDENCIES

### Required

• Python 2.7+ or Python 3.2+

• numpy

• pyshp

• pyproj (required for geodetic calculations)

### Optional

• cython

• scipy

Cython is an optional dependency used to speed up select functions. In general, enhanced-performance functions will then be called automatically when available, otherwise Karta will fall back to numpy and pure-Python versions.

When installing from PyPI, C source code is provided and will be automatically compiled if a suitable compiler is available.

## TESTING

To run all unit tests, execute

python tests/runtests.py

##LICENSE

This software is provided under the MIT license.

###MIT License:

Permission is hereby granted, free of charge, to any person obtaining a copy of this software and associated documentation files (the “Software”), to deal in the Software without restriction, including without limitation the rights to use, copy, modify, merge, publish, distribute, sublicense, and/or sell copies of the Software, and to permit persons to whom the Software is furnished to do so, subject to the following conditions:

The above copyright notice and this permission notice shall be included in all copies or substantial portions of the Software.

THE SOFTWARE IS PROVIDED “AS IS”, WITHOUT WARRANTY OF ANY KIND, EXPRESS OR IMPLIED, INCLUDING BUT NOT LIMITED TO THE WARRANTIES OF MERCHANTABILITY, FITNESS FOR A PARTICULAR PURPOSE AND NONINFRINGEMENT. IN NO EVENT SHALL THE AUTHORS OR COPYRIGHT HOLDERS BE LIABLE FOR ANY CLAIM, DAMAGES OR OTHER LIABILITY, WHETHER IN AN ACTION OF CONTRACT, TORT OR OTHERWISE, ARISING FROM, OUT OF OR IN CONNECTION WITH THE SOFTWARE OR THE USE OR OTHER DEALINGS IN THE SOFTWARE.