flopy.utils.geometry module

Container objects for working with geometric information

class Collection(geometries=())

Bases: list

The collection object is container for a group of flopy geometries

This class acts as a base class for MultiPoint, MultiLineString, and MultiPolygon classes. This class can also accept a mix of geometries and act as a stand alone container.

Parameters:

geometries (list) – list of flopy.util.geometry objects

property bounds

Method to calculate the bounding box of the collection

Return type:

tuple (xmin, ymin, xmax, ymax)

plot(ax=None, **kwargs)

Plotting method for collection

Parameters:

• ax (matplotlib.axes object) –

• kwargs (keyword arguments) – matplotlib keyword arguments

Return type:

matplotlib.axes object

class LineString(coordinates)

Bases: Shape

property bounds

has_z = False

plot(ax=None, **kwargs)

property pyshp_parts

shapeType = 3

type = 'LineString'

property x

property y

property z

class MultiLineString(linestrings=())

Bases: Collection

Container for housing and describing multilinestring geometries (e.g. to be

read or written to shapefiles or other geographic data formats)

Parameters:

linestrings (list, tuple, default ()) – list of flopy.utils.geometry.LineString objects

class MultiPoint(points=())

Bases: Collection

Container for housing and describing multipoint geometries (e.g. to be

read or written to shapefiles or other geographic data formats)

Parameters:

points (list, tuple, default ()) – list of flopy.utils.geometry.Point objects

class MultiPolygon(polygons=())

Bases: Collection

Container for housing and describing multipolygon geometries (e.g. to be

read or written to shapefiles or other geographic data formats)

Parameters:

polygons (list, tuple, default ()) – list of flopy.utils.geometry.Polygon objects

class Point(*coordinates)

Bases: Shape

property bounds

has_z = False

plot(ax=None, **kwargs)

property pyshp_parts

shapeType = 1

type = 'Point'

property x

property y

property z

class Polygon(exterior, interiors=None)

Bases: Shape

property bounds

get_patch(**kwargs)

property patch

plot(ax=None, **kwargs)

Plot the feature. :param ax: :type ax: matplotlib.pyplot axes instance :param Accepts keyword arguments to descartes.PolygonPatch. Requires the: :param descartes package (pip install descartes).:

property pyshp_parts

shapeType = 5

type = 'Polygon'

class Shape(shapetype, coordinates=None, exterior=None, interiors=None)

Bases: object

Parent class for handling geo interfacing, do not instantiate directly

Parameters:

• type (str) – shapetype string

• coordinates (list or tuple) – list of tuple of point or linestring coordinates

• exterior (list or tuple) – 2d list of polygon coordinates

• interiors (list or tuple) – 2d or 3d list of polygon interiors

static from_geojson(geo_interface)

Method to load from geojson

Parameters:

geo_interface (geojson, dict) – geojson compliant representation of a linestring

Return type:

Polygon, LineString, or Point

property geojson

distance(x0, y0, x1, y1)

General distance equation

Parameters:

• x0 (float) –

• y0 (float) –

• x1 (np.array or float) –

• y1 (np.array or float) –

Return type:

distance

get_polygon_area(geom)

Calculate the area of a closed polygon

Parameters:

geom (geospatial representation of polygon) –

accepted types:

vertices np.array([(x, y),….]) geojson.Polygon shapely.Polygon shapefile.Shape

Returns:

area – area of polygon centroid

Return type:

float

get_polygon_centroid(geom)

Calculate the centroid of a closed polygon

Parameters:

geom (geospatial representation of polygon) –

accepted types:

vertices np.array([(x, y),….]) geojson.Polygon shapely.Polygon shapefile.Shape

Returns:

centroid – (x, y) of polygon centroid

Return type:

tuple

is_clockwise(*geom)

Determine if a ring is defined clockwise

Parameters:

*geom (geospatial representation of polygon) –

accepted types:

vertices [(x, y),….] geojson.Polygon shapely.Polygon shapefile.Shape x and y vertices: [x1, x2, x3], [y1, y2, y3]

Returns:

clockwise – True when the ring is defined clockwise, False otherwise

Return type:

bool

point_in_polygon(xc, yc, polygon)

Use the ray casting algorithm to determine if a point is within a polygon. Enables very fast intersection calculations!

Parameters:

• xc (np.ndarray) – 2d array of xpoints

• yc (np.ndarray) – 2d array of ypoints

• polygon (iterable (list)) – polygon vertices [(x0, y0),….(xn, yn)] note: polygon can be open or closed

Returns:

mask – True value means point is in polygon!

Return type:

np.array

project_point_onto_xc_line(line, pts, d0=0, calc_dist=False)

Method to project points onto a cross sectional line that is defined by distance. Used for plotting MODPATH results on to a cross section!

linelist or np.ndarray

numpy array of [(x0, y0), (x1, y1)] that defines the line to project on to

ptslist or np.ndarray

numpy array of [(x, y),] points to be projected

d0 : distance offset along line of min(xl) calc_dist : bool

boolean flag to indicate that the return type is distance offset by d0 (calculated from line[0]). If false this will return the “projected” xy location along the cross-sectional line

Returns:

tuple of (x , y) or distance

rotate(x, y, xoff, yoff, angrot_radians)

Given x and y array-like values calculate the rotation about an arbitrary origin and then return the rotated coordinates.

transform(x, y, xoff, yoff, angrot_radians, length_multiplier=1.0, inverse=False)

Given x and y array-like values calculate the translation about an arbitrary origin and then return the rotated coordinates.