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Fiona

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Fiona streams simple feature data to and from GIS formats like GeoPackage and Shapefile.

Fiona can read and write real-world data using multi-layered GIS formats, zipped and in-memory virtual file systems, from files on your hard drive or in cloud storage. This project includes Python modules and a command line interface (CLI).

Fiona depends on GDAL but is different from GDAL's own bindings. Fiona is designed to be highly productive and to make it easy to write code which is easy to read.

Installation

Fiona has several extension modules which link against libgdal. This complicates installation. Binary distributions (wheels) containing libgdal and its own dependencies are available from the Python Package Index and can be installed using pip.

pip install fiona

These wheels are mainly intended to make installation easy for simple applications, not so much for production. They are not tested for compatibility with all other binary wheels, conda packages, or QGIS, and omit many of GDAL's optional format drivers. If you need, for example, GML support you will need to build and install Fiona from a source distribution. It is possible to install Fiona from source using pip (version >= 22.3) and the --no-binary option. A specific GDAL installation can be selected by setting the GDAL_CONFIG environment variable.

pip install -U pip
pip install --no-binary fiona fiona

Many users find Anaconda and conda-forge a good way to install Fiona and get access to more optional format drivers (like GML).

Fiona 1.10 requires Python 3.8 or higher and GDAL 3.4 or higher.

Python Usage

Features are read from and written to file-like Collection objects returned from the fiona.open() function. Features are data classes modeled on the GeoJSON format. They don't have any spatial methods of their own, so if you want to transform them you will need Shapely or something like it. Here is an example of using Fiona to read some features from one data file, change their geometry attributes using Shapely, and write them to a new data file.

import fiona
from fiona import Feature, Geometry
from shapely.geometry import mapping, shape

# Open a file for reading. We'll call this the source.
with fiona.open(
    "zip+https://github.com/Toblerity/Fiona/files/11151652/coutwildrnp.zip"
) as src:

    # The file we'll write to must be initialized with a coordinate
    # system, a format driver name, and a record schema. We can get
    # initial values from the open source's profile property and then
    # modify them as we need.
    profile = src.profile
    profile["schema"]["geometry"] = "Point"
    profile["driver"] = "GPKG"

    # Open an output file, using the same format driver and coordinate
    # reference system as the source. The profile mapping fills in the
    # keyword parameters of fiona.open.
    with fiona.open("centroids.gpkg", "w", **profile) as dst:

        # Process only the feature records intersecting a box.
        for feat in src.filter(bbox=(-107.0, 37.0, -105.0, 39.0)):

            # Get the feature's centroid.
            centroid_shp = shape(feat.geometry).centroid
            new_geom = Geometry.from_dict(centroid_shp)

            # Write the feature out.
            dst.write(
                Feature(geometry=new_geom, properties=f.properties)
            )

    # The destination's contents are flushed to disk and the file is
    # closed when its with block ends. This effectively
    # executes ``dst.flush(); dst.close()``.

CLI Usage

Fiona's command line interface, named "fio", is documented at docs/cli.rst. The CLI has a number of different commands. Its fio cat command streams GeoJSON features from any dataset.

$ fio cat --compact tests/data/coutwildrnp.shp | jq -c '.'
{"geometry":{"coordinates":[[[-111.73527526855469,41.995094299316406],...]]}}
...

Documentation

For more details about this project, please see: