landlab.graph.structured_quad package#

Subpackages#

Submodules#

landlab.graph.structured_quad.dual_structured_quad module#

class DualRectilinearGraph(node_y_and_x)[source]#

Bases: DualGraph, RectilinearGraph

Create a dual graph for a rectilinear grid.

Examples

>>> from landlab.graph import DualRectilinearGraph
>>> graph = DualRectilinearGraph(([0, 1, 3], [0, 5, 15, 30]))
>>> graph.x_of_corner 
array([ 2.5, 10. , 22.5,
        2.5, 10. , 22.5])
>>> graph.y_of_corner 
array([ 0.5, 0.5, 0.5,
        2. , 2. , 2. ])
>>> graph.number_of_cells == 2
True
>>> graph.faces_at_cell
array([[3, 5, 2, 0],
       [4, 6, 3, 1]])
property adjacent_corners_at_corner#

Get adjacent corners.

See also

Graph.adjacent_nodes_at_node

property adjacent_faces_at_face#
property angle_of_face#

Get the angle of each face.

See also

Graph.angle_of_link

property area_of_cell#

Get the area of each cell.

See also

Graph.area_of_patch

property cells_at_corner#
property cells_at_face#
property corner_at_face_head#

Get corners at face head.

See also

Graph.node_at_link_head

property corner_at_face_tail#

Get corners at face tail.

See also

Graph.node_at_link_tail

property corner_x#
property corner_y#
property corners#

A shaped array of corner ids.

See also

Graph.nodes

property corners_at_bottom_edge#
property corners_at_cell#

Get the corners that define a cell.

See also

Graph.nodes_at_patch

property corners_at_face#

Get corners at either end of faces.

See also

Graph.nodes_at_link

property corners_at_left_edge#
property corners_at_nodes_of_grid#

Nodes at nodes of grid.

See also

Graph.nodes_at_corners_of_grid

property corners_at_right_edge#
property corners_at_top_edge#
property face_dirs_at_corner#
property faces_at_cell#

Get the faces that define a cell.

See also

Graph.links_at_patch

property faces_at_corner#
static get_corners(node_y_and_x)[source]#
property horizontal_faces#
property length_of_face#

Get the length of faces.

See also

Graph.length_of_link

property midpoint_of_face#

Get the middle of faces.

See also

Graph.midpoint_of_link

property node_corners#
property number_of_cells#

Get the number of cells.

See also

Graph.number_of_patches

property number_of_corner_columns#
property number_of_corner_rows#
property number_of_corners#

Get total number of corners.

See also

Graph.number_of_nodes

property number_of_faces#

Get corners at face head.

See also

Graph.number_of_links

property perimeter_corners#
property unit_vector_at_corner#

Get a unit vector for each corner.

See also

Graph.unit_vector_at_node

property unit_vector_at_face#

Make arrays to store the unit vectors associated with each face.

See also

Graph.unit_vector_at_link

property vertical_faces#
property x_of_corner#

Get x-coordinate of corner.

See also

Graph.x_of_node

property xy_of_cell#

Get the centroid of each cell.

See also

Graph.xy_of_patch

property xy_of_corner#

Get x and y-coordinates of corner.

See also

Graph.xy_of_node

property xy_of_face#
property y_of_corner#

Get y-coordinate of corner.

See also

Graph.y_of_node

class DualStructuredQuadGraph(node_y_and_x, shape=None, sort=True)[source]#

Bases: DualGraph, StructuredQuadGraph

Dual graph of a structured grid of quadrilaterals.

Examples

>>> from landlab.graph import DualStructuredQuadGraph
>>> node_y = [-1, -2, -3,
...            0,  0,  0,
...            1,  2,  3]
>>> node_x = [ 0,  1,  2,
...            0,  2,  3,
...            0,  1,  2]
>>> graph = DualStructuredQuadGraph((node_y, node_x), shape=(3, 3), sort=True)
>>> graph.number_of_corners == 4
True
>>> graph.y_of_corner
array([-1.25, -0.75,  0.75,  1.25])
>>> graph.x_of_corner
array([ 2.  ,  0.75,  0.75,  2.  ])
>>> graph.node_at_cell
array([4])
property adjacent_corners_at_corner#

Get adjacent corners.

See also

Graph.adjacent_nodes_at_node

property adjacent_faces_at_face#
property angle_of_face#

Get the angle of each face.

See also

Graph.angle_of_link

property area_of_cell#

Get the area of each cell.

See also

Graph.area_of_patch

property cells_at_corner#
property cells_at_face#
property corner_at_face_head#

Get corners at face head.

See also

Graph.node_at_link_head

property corner_at_face_tail#

Get corners at face tail.

See also

Graph.node_at_link_tail

property corner_x#
property corner_y#
property corners#

A shaped array of corner ids.

See also

Graph.nodes

property corners_at_bottom_edge#
property corners_at_cell#

Get the corners that define a cell.

See also

Graph.nodes_at_patch

property corners_at_face#

Get corners at either end of faces.

See also

Graph.nodes_at_link

property corners_at_left_edge#
property corners_at_nodes_of_grid#

Nodes at nodes of grid.

See also

Graph.nodes_at_corners_of_grid

property corners_at_right_edge#
property corners_at_top_edge#
property face_dirs_at_corner#
property faces_at_cell#

Get the faces that define a cell.

See also

Graph.links_at_patch

property faces_at_corner#
static get_corners(node_y_and_x, shape)[source]#
static get_node_at_cell(shape)[source]#

Set up an array that gives the node at each cell.

Examples

>>> from landlab.graph.structured_quad import DualStructuredQuadGraph
>>> DualStructuredQuadGraph.get_node_at_cell((5, 6))
array([ 7,  8,  9, 10,
       13, 14, 15, 16,
       19, 20, 21, 22])
static get_nodes_at_face(shape)[source]#

Set up an array that gives the nodes on either side of each face.

Examples

>>> from landlab.graph.structured_quad import DualStructuredQuadGraph
>>> DualStructuredQuadGraph.get_nodes_at_face((3, 4))
array([[ 1,  5], [ 2,  6],
       [ 4,  5], [ 5,  6], [ 6,  7],
       [ 5,  9], [ 6, 10]])
property horizontal_faces#
property length_of_face#

Get the length of faces.

See also

Graph.length_of_link

property midpoint_of_face#

Get the middle of faces.

See also

Graph.midpoint_of_link

property node_corners#
property number_of_cells#

Get the number of cells.

See also

Graph.number_of_patches

property number_of_corner_columns#
property number_of_corner_rows#
property number_of_corners#

Get total number of corners.

See also

Graph.number_of_nodes

property number_of_faces#

Get corners at face head.

See also

Graph.number_of_links

property perimeter_corners#
property unit_vector_at_corner#

Get a unit vector for each corner.

See also

Graph.unit_vector_at_node

property unit_vector_at_face#

Make arrays to store the unit vectors associated with each face.

See also

Graph.unit_vector_at_link

property vertical_faces#
property x_of_corner#

Get x-coordinate of corner.

See also

Graph.x_of_node

property xy_of_cell#

Get the centroid of each cell.

See also

Graph.xy_of_patch

property xy_of_corner#

Get x and y-coordinates of corner.

See also

Graph.xy_of_node

property xy_of_face#
property y_of_corner#

Get y-coordinate of corner.

See also

Graph.y_of_node

class DualUniformRectilinearGraph(shape, spacing=1.0, origin=(0.0, 0.0))[source]#

Bases: DualGraph, UniformRectilinearGraph

Create a dual graph for a uniform rectilinear grid.

Examples

>>> from landlab.graph import DualUniformRectilinearGraph
>>> graph = DualUniformRectilinearGraph((4, 3))
>>> graph.x_of_corner 
array([ 0.5, 1.5,
        0.5, 1.5,
        0.5, 1.5])
>>> graph.y_of_corner 
array([ 0.5, 0.5,
        1.5, 1.5,
        2.5, 2.5])
>>> graph.number_of_cells == 2
True
>>> graph.faces_at_cell
array([[2, 3, 1, 0],
       [5, 6, 4, 3]])
property adjacent_corners_at_corner#

Get adjacent corners.

See also

Graph.adjacent_nodes_at_node

property adjacent_faces_at_face#
property angle_of_face#

Get the angle of each face.

See also

Graph.angle_of_link

property area_of_cell#

Get the area of each cell.

See also

Graph.area_of_patch

property cells_at_corner#
property cells_at_face#
property corner_at_face_head#

Get corners at face head.

See also

Graph.node_at_link_head

property corner_at_face_tail#

Get corners at face tail.

See also

Graph.node_at_link_tail

property corner_x#
property corner_y#
property corners#

A shaped array of corner ids.

See also

Graph.nodes

property corners_at_bottom_edge#
property corners_at_cell#

Get the corners that define a cell.

See also

Graph.nodes_at_patch

property corners_at_face#

Get corners at either end of faces.

See also

Graph.nodes_at_link

property corners_at_left_edge#
property corners_at_nodes_of_grid#

Nodes at nodes of grid.

See also

Graph.nodes_at_corners_of_grid

property corners_at_right_edge#
property corners_at_top_edge#
property face_dirs_at_corner#
property faces_at_cell#

Get the faces that define a cell.

See also

Graph.links_at_patch

property faces_at_corner#
property horizontal_faces#
property length_of_face#

Get the length of faces.

See also

Graph.length_of_link

property midpoint_of_face#

Get the middle of faces.

See also

Graph.midpoint_of_link

property node_corners#
property number_of_cells#

Get the number of cells.

See also

Graph.number_of_patches

property number_of_corner_columns#
property number_of_corner_rows#
property number_of_corners#

Get total number of corners.

See also

Graph.number_of_nodes

property number_of_faces#

Get corners at face head.

See also

Graph.number_of_links

property perimeter_corners#
property unit_vector_at_corner#

Get a unit vector for each corner.

See also

Graph.unit_vector_at_node

property unit_vector_at_face#

Make arrays to store the unit vectors associated with each face.

See also

Graph.unit_vector_at_link

property vertical_faces#
property x_of_corner#

Get x-coordinate of corner.

See also

Graph.x_of_node

property xy_of_cell#

Get the centroid of each cell.

See also

Graph.xy_of_patch

property xy_of_corner#

Get x and y-coordinates of corner.

See also

Graph.xy_of_node

property xy_of_face#
property y_of_corner#

Get y-coordinate of corner.

See also

Graph.y_of_node

landlab.graph.structured_quad.structured_quad module#

class RectilinearGraph(nodes, sort=False)[source]#

Bases: StructuredQuadGraphExtras

Graph of a rectlinear grid of nodes.

Examples

>>> from landlab.graph import RectilinearGraph
>>> graph = RectilinearGraph(([0, 1, 2, 3], [1, 4, 8]))
>>> graph.number_of_nodes
12
>>> graph.y_of_node 
array([ 0., 0., 0.,
        1., 1., 1.,
        2., 2., 2.,
        3., 3., 3.])
>>> graph.x_of_node 
array([ 1., 4., 8.,
        1., 4., 8.,
        1., 4., 8.,
        1., 4., 8.])

Define a graph of connected nodes.

Parameters

mesh (Dataset) – xarray Dataset that defines the topology in ugrid format.

static setup_node_y_and_x(coords)[source]#
class StructuredQuadGraph(coords, shape=None, sort=False)[source]#

Bases: StructuredQuadGraphExtras

Define a graph of connected nodes.

Parameters

mesh (Dataset) – xarray Dataset that defines the topology in ugrid format.

static setup_node_y_and_x(yx_at_node, shape=None)[source]#
class StructuredQuadGraphExtras(node_y_and_x, sort=False)[source]#

Bases: StructuredQuadGraphTopology, Graph

Define a graph of connected nodes.

Parameters

mesh (Dataset) – xarray Dataset that defines the topology in ugrid format.

Get nodes at either end of links.

Examples

>>> from landlab.graph import Graph
>>> node_x, node_y = [0, 1, 2, 0, 1, 2, 0, 1, 2], [0, 0, 0, 1, 1, 1, 2, 2, 2]
>>> links = ((0, 1), (1, 2),
...          (0, 3), (1, 4), (2, 5),
...          (3, 4), (4, 5),
...          (3, 6), (4, 7), (5, 8),
...          (6, 7), (7, 8))
>>> graph = Graph((node_y, node_x), links=links)
>>> graph.nodes_at_link 
array([[0, 1], [1, 2],
       [0, 3], [1, 4], [2, 5],
       [3, 4], [4, 5],
       [3, 6], [4, 7], [5, 8],
       [6, 7], [7, 8]])
class StructuredQuadGraphTopology(shape)[source]#

Bases: object

property corner_nodes#
property nodes#

A shaped array of node ids.

Returns

Node IDs in an array shaped as number_of_node_rows by number_of_node_columns.

Return type

ndarray

property nodes_at_bottom_edge#
property nodes_at_corners_of_grid#

Nodes at corners of grid.

The nodes at at the corners of the grid. The nodes are returned counterclockwise starting with the upper-right.

Returns

Nodes at the four corners.

Return type

tuple of int

Examples

>>> from landlab.graph import UniformRectilinearGraph
>>> graph = UniformRectilinearGraph((4, 5))
>>> graph.nodes_at_corners_of_grid
(19, 15, 0, 4)
nodes_at_edge(edge)[source]#
property nodes_at_left_edge#
property nodes_at_right_edge#
property nodes_at_top_edge#
property number_of_node_columns#
property number_of_node_rows#
property patches_at_node#
property perimeter_nodes#
property shape#
class StructuredQuadLayout[source]#

Bases: ABC

static corner_nodes(shape)[source]#
abstract patches_at_node()[source]#
abstract perimeter_nodes()[source]#
class StructuredQuadLayoutCython[source]#

Bases: StructuredQuadLayout

Get links that define patches for a raster grid.

Examples

>>> from landlab.graph.structured_quad.structured_quad import StructuredQuadLayoutCython
>>> StructuredQuadLayoutCython.links_at_patch((3, 4))
array([[ 4,  7,  3,  0], [ 5,  8,  4,  1], [ 6,  9,  5,  2],
       [11, 14, 10,  7], [12, 15, 11,  8], [13, 16, 12,  9]])

Examples

>>> from landlab.graph.structured_quad.structured_quad import StructuredQuadLayoutCython
>>> StructuredQuadLayoutCython.nodes_at_link((3, 4))
array([[ 0,  1], [ 1,  2], [ 2,  3],
       [ 0,  4], [ 1,  5], [ 2,  6], [ 3,  7],
       [ 4,  5], [ 5,  6], [ 6,  7],
       [ 4,  8], [ 5,  9], [ 6, 10], [ 7, 11],
       [ 8,  9], [ 9, 10], [10, 11]])
static patches_at_node(shape)[source]#
static perimeter_nodes(shape)[source]#
class StructuredQuadLayoutPython[source]#

Bases: StructuredQuadLayout

static patches_at_node(shape)[source]#
static perimeter_nodes(shape)[source]#
class UniformRectilinearGraph(shape, spacing=1.0, origin=0.0, sort=False)[source]#

Bases: StructuredQuadGraphExtras

Graph of a structured grid of quadrilaterals.

Examples

>>> from landlab.graph import UniformRectilinearGraph
>>> graph = UniformRectilinearGraph((4, 3), spacing=(1, 2), origin=(-1, 0))
>>> graph.number_of_nodes
12
>>> graph.y_of_node 
array([-1., -1., -1.,
        0.,  0.,  0.,
        1.,  1.,  1.,
        2.,  2.,  2.])
>>> graph.x_of_node 
array([ 0.,  2.,  4.,
        0.,  2.,  4.,
        0.,  2.,  4.,
        0.,  2.,  4.])
>>> graph.links_at_node 
array([[ 0,  2, -1, -1], [ 1,  3,  0, -1], [-1,  4,  1, -1],
       [ 5,  7, -1,  2], [ 6,  8,  5,  3], [-1,  9,  6,  4],
       [10, 12, -1,  7], [11, 13, 10,  8], [-1, 14, 11,  9],
       [15, -1, -1, 12], [16, -1, 15, 13], [-1, -1, 16, 14]])
>>> graph.link_dirs_at_node 
array([[-1, -1,  0,  0], [-1, -1,  1,  0], [ 0, -1,  1,  0],
       [-1, -1,  0,  1], [-1, -1,  1,  1], [ 0, -1,  1,  1],
       [-1, -1,  0,  1], [-1, -1,  1,  1], [ 0, -1,  1,  1],
       [-1,  0,  0,  1], [-1,  0,  1,  1], [ 0,  0,  1,  1]], dtype=int8)
>>> graph.nodes_at_link 
array([[ 0,  1], [ 1,  2], [ 0,  3], [ 1,  4], [ 2,  5],
       [ 3,  4], [ 4,  5], [ 3,  6], [ 4,  7], [ 5,  8],
       [ 6,  7], [ 7,  8], [ 6,  9], [ 7, 10], [ 8, 11],
       [ 9, 10], [10, 11]])
>>> graph.links_at_patch 
array([[ 3,  5,  2,  0], [ 4,  6,  3,  1],
       [ 8, 10,  7,  5], [ 9, 11,  8,  6],
       [13, 15, 12, 10], [14, 16, 13, 11]])
>>> graph.nodes_at_patch 
array([[ 4,  3,  0,  1], [ 5,  4,  1,  2],
       [ 7,  6,  3,  4], [ 8,  7,  4,  5],
       [10,  9,  6,  7], [11, 10,  7,  8]])

Define a graph of connected nodes.

Parameters

mesh (Dataset) – xarray Dataset that defines the topology in ugrid format.

property dx#
property dy#
property origin#
property spacing#

Module contents#

class DualRectilinearGraph(node_y_and_x)[source]#

Bases: DualGraph, RectilinearGraph

Create a dual graph for a rectilinear grid.

Examples

>>> from landlab.graph import DualRectilinearGraph
>>> graph = DualRectilinearGraph(([0, 1, 3], [0, 5, 15, 30]))
>>> graph.x_of_corner 
array([ 2.5, 10. , 22.5,
        2.5, 10. , 22.5])
>>> graph.y_of_corner 
array([ 0.5, 0.5, 0.5,
        2. , 2. , 2. ])
>>> graph.number_of_cells == 2
True
>>> graph.faces_at_cell
array([[3, 5, 2, 0],
       [4, 6, 3, 1]])
property adjacent_corners_at_corner#

Get adjacent corners.

See also

Graph.adjacent_nodes_at_node

property adjacent_faces_at_face#
property angle_of_face#

Get the angle of each face.

See also

Graph.angle_of_link

property area_of_cell#

Get the area of each cell.

See also

Graph.area_of_patch

property cells_at_corner#
property cells_at_face#
property corner_at_face_head#

Get corners at face head.

See also

Graph.node_at_link_head

property corner_at_face_tail#

Get corners at face tail.

See also

Graph.node_at_link_tail

property corner_x#
property corner_y#
property corners#

A shaped array of corner ids.

See also

Graph.nodes

property corners_at_bottom_edge#
property corners_at_cell#

Get the corners that define a cell.

See also

Graph.nodes_at_patch

property corners_at_face#

Get corners at either end of faces.

See also

Graph.nodes_at_link

property corners_at_left_edge#
property corners_at_nodes_of_grid#

Nodes at nodes of grid.

See also

Graph.nodes_at_corners_of_grid

property corners_at_right_edge#
property corners_at_top_edge#
property face_dirs_at_corner#
property faces_at_cell#

Get the faces that define a cell.

See also

Graph.links_at_patch

property faces_at_corner#
static get_corners(node_y_and_x)[source]#
property horizontal_faces#
property length_of_face#

Get the length of faces.

See also

Graph.length_of_link

property midpoint_of_face#

Get the middle of faces.

See also

Graph.midpoint_of_link

property node_corners#
property number_of_cells#

Get the number of cells.

See also

Graph.number_of_patches

property number_of_corner_columns#
property number_of_corner_rows#
property number_of_corners#

Get total number of corners.

See also

Graph.number_of_nodes

property number_of_faces#

Get corners at face head.

See also

Graph.number_of_links

property perimeter_corners#
property unit_vector_at_corner#

Get a unit vector for each corner.

See also

Graph.unit_vector_at_node

property unit_vector_at_face#

Make arrays to store the unit vectors associated with each face.

See also

Graph.unit_vector_at_link

property vertical_faces#
property x_of_corner#

Get x-coordinate of corner.

See also

Graph.x_of_node

property xy_of_cell#

Get the centroid of each cell.

See also

Graph.xy_of_patch

property xy_of_corner#

Get x and y-coordinates of corner.

See also

Graph.xy_of_node

property xy_of_face#
property y_of_corner#

Get y-coordinate of corner.

See also

Graph.y_of_node

class DualStructuredQuadGraph(node_y_and_x, shape=None, sort=True)[source]#

Bases: DualGraph, StructuredQuadGraph

Dual graph of a structured grid of quadrilaterals.

Examples

>>> from landlab.graph import DualStructuredQuadGraph
>>> node_y = [-1, -2, -3,
...            0,  0,  0,
...            1,  2,  3]
>>> node_x = [ 0,  1,  2,
...            0,  2,  3,
...            0,  1,  2]
>>> graph = DualStructuredQuadGraph((node_y, node_x), shape=(3, 3), sort=True)
>>> graph.number_of_corners == 4
True
>>> graph.y_of_corner
array([-1.25, -0.75,  0.75,  1.25])
>>> graph.x_of_corner
array([ 2.  ,  0.75,  0.75,  2.  ])
>>> graph.node_at_cell
array([4])
property adjacent_corners_at_corner#

Get adjacent corners.

See also

Graph.adjacent_nodes_at_node

property adjacent_faces_at_face#
property angle_of_face#

Get the angle of each face.

See also

Graph.angle_of_link

property area_of_cell#

Get the area of each cell.

See also

Graph.area_of_patch

property cells_at_corner#
property cells_at_face#
property corner_at_face_head#

Get corners at face head.

See also

Graph.node_at_link_head

property corner_at_face_tail#

Get corners at face tail.

See also

Graph.node_at_link_tail

property corner_x#
property corner_y#
property corners#

A shaped array of corner ids.

See also

Graph.nodes

property corners_at_bottom_edge#
property corners_at_cell#

Get the corners that define a cell.

See also

Graph.nodes_at_patch

property corners_at_face#

Get corners at either end of faces.

See also

Graph.nodes_at_link

property corners_at_left_edge#
property corners_at_nodes_of_grid#

Nodes at nodes of grid.

See also

Graph.nodes_at_corners_of_grid

property corners_at_right_edge#
property corners_at_top_edge#
property face_dirs_at_corner#
property faces_at_cell#

Get the faces that define a cell.

See also

Graph.links_at_patch

property faces_at_corner#
static get_corners(node_y_and_x, shape)[source]#
static get_node_at_cell(shape)[source]#

Set up an array that gives the node at each cell.

Examples

>>> from landlab.graph.structured_quad import DualStructuredQuadGraph
>>> DualStructuredQuadGraph.get_node_at_cell((5, 6))
array([ 7,  8,  9, 10,
       13, 14, 15, 16,
       19, 20, 21, 22])
static get_nodes_at_face(shape)[source]#

Set up an array that gives the nodes on either side of each face.

Examples

>>> from landlab.graph.structured_quad import DualStructuredQuadGraph
>>> DualStructuredQuadGraph.get_nodes_at_face((3, 4))
array([[ 1,  5], [ 2,  6],
       [ 4,  5], [ 5,  6], [ 6,  7],
       [ 5,  9], [ 6, 10]])
property horizontal_faces#
property length_of_face#

Get the length of faces.

See also

Graph.length_of_link

property midpoint_of_face#

Get the middle of faces.

See also

Graph.midpoint_of_link

property node_corners#
property number_of_cells#

Get the number of cells.

See also

Graph.number_of_patches

property number_of_corner_columns#
property number_of_corner_rows#
property number_of_corners#

Get total number of corners.

See also

Graph.number_of_nodes

property number_of_faces#

Get corners at face head.

See also

Graph.number_of_links

property perimeter_corners#
property unit_vector_at_corner#

Get a unit vector for each corner.

See also

Graph.unit_vector_at_node

property unit_vector_at_face#

Make arrays to store the unit vectors associated with each face.

See also

Graph.unit_vector_at_link

property vertical_faces#
property x_of_corner#

Get x-coordinate of corner.

See also

Graph.x_of_node

property xy_of_cell#

Get the centroid of each cell.

See also

Graph.xy_of_patch

property xy_of_corner#

Get x and y-coordinates of corner.

See also

Graph.xy_of_node

property xy_of_face#
property y_of_corner#

Get y-coordinate of corner.

See also

Graph.y_of_node

class DualUniformRectilinearGraph(shape, spacing=1.0, origin=(0.0, 0.0))[source]#

Bases: DualGraph, UniformRectilinearGraph

Create a dual graph for a uniform rectilinear grid.

Examples

>>> from landlab.graph import DualUniformRectilinearGraph
>>> graph = DualUniformRectilinearGraph((4, 3))
>>> graph.x_of_corner 
array([ 0.5, 1.5,
        0.5, 1.5,
        0.5, 1.5])
>>> graph.y_of_corner 
array([ 0.5, 0.5,
        1.5, 1.5,
        2.5, 2.5])
>>> graph.number_of_cells == 2
True
>>> graph.faces_at_cell
array([[2, 3, 1, 0],
       [5, 6, 4, 3]])
property adjacent_corners_at_corner#

Get adjacent corners.

See also

Graph.adjacent_nodes_at_node

property adjacent_faces_at_face#
property angle_of_face#

Get the angle of each face.

See also

Graph.angle_of_link

property area_of_cell#

Get the area of each cell.

See also

Graph.area_of_patch

property cells_at_corner#
property cells_at_face#
property corner_at_face_head#

Get corners at face head.

See also

Graph.node_at_link_head

property corner_at_face_tail#

Get corners at face tail.

See also

Graph.node_at_link_tail

property corner_x#
property corner_y#
property corners#

A shaped array of corner ids.

See also

Graph.nodes

property corners_at_bottom_edge#
property corners_at_cell#

Get the corners that define a cell.

See also

Graph.nodes_at_patch

property corners_at_face#

Get corners at either end of faces.

See also

Graph.nodes_at_link

property corners_at_left_edge#
property corners_at_nodes_of_grid#

Nodes at nodes of grid.

See also

Graph.nodes_at_corners_of_grid

property corners_at_right_edge#
property corners_at_top_edge#
property face_dirs_at_corner#
property faces_at_cell#

Get the faces that define a cell.

See also

Graph.links_at_patch

property faces_at_corner#
property horizontal_faces#
property length_of_face#

Get the length of faces.

See also

Graph.length_of_link

property midpoint_of_face#

Get the middle of faces.

See also

Graph.midpoint_of_link

property node_corners#
property number_of_cells#

Get the number of cells.

See also

Graph.number_of_patches

property number_of_corner_columns#
property number_of_corner_rows#
property number_of_corners#

Get total number of corners.

See also

Graph.number_of_nodes

property number_of_faces#

Get corners at face head.

See also

Graph.number_of_links

property perimeter_corners#
property unit_vector_at_corner#

Get a unit vector for each corner.

See also

Graph.unit_vector_at_node

property unit_vector_at_face#

Make arrays to store the unit vectors associated with each face.

See also

Graph.unit_vector_at_link

property vertical_faces#
property x_of_corner#

Get x-coordinate of corner.

See also

Graph.x_of_node

property xy_of_cell#

Get the centroid of each cell.

See also

Graph.xy_of_patch

property xy_of_corner#

Get x and y-coordinates of corner.

See also

Graph.xy_of_node

property xy_of_face#
property y_of_corner#

Get y-coordinate of corner.

See also

Graph.y_of_node

class RectilinearGraph(nodes, sort=False)[source]#

Bases: StructuredQuadGraphExtras

Graph of a rectlinear grid of nodes.

Examples

>>> from landlab.graph import RectilinearGraph
>>> graph = RectilinearGraph(([0, 1, 2, 3], [1, 4, 8]))
>>> graph.number_of_nodes
12
>>> graph.y_of_node 
array([ 0., 0., 0.,
        1., 1., 1.,
        2., 2., 2.,
        3., 3., 3.])
>>> graph.x_of_node 
array([ 1., 4., 8.,
        1., 4., 8.,
        1., 4., 8.,
        1., 4., 8.])

Define a graph of connected nodes.

Parameters

mesh (Dataset) – xarray Dataset that defines the topology in ugrid format.

static setup_node_y_and_x(coords)[source]#
class StructuredQuadGraph(coords, shape=None, sort=False)[source]#

Bases: StructuredQuadGraphExtras

Define a graph of connected nodes.

Parameters

mesh (Dataset) – xarray Dataset that defines the topology in ugrid format.

static setup_node_y_and_x(yx_at_node, shape=None)[source]#
class UniformRectilinearGraph(shape, spacing=1.0, origin=0.0, sort=False)[source]#

Bases: StructuredQuadGraphExtras

Graph of a structured grid of quadrilaterals.

Examples

>>> from landlab.graph import UniformRectilinearGraph
>>> graph = UniformRectilinearGraph((4, 3), spacing=(1, 2), origin=(-1, 0))
>>> graph.number_of_nodes
12
>>> graph.y_of_node 
array([-1., -1., -1.,
        0.,  0.,  0.,
        1.,  1.,  1.,
        2.,  2.,  2.])
>>> graph.x_of_node 
array([ 0.,  2.,  4.,
        0.,  2.,  4.,
        0.,  2.,  4.,
        0.,  2.,  4.])
>>> graph.links_at_node 
array([[ 0,  2, -1, -1], [ 1,  3,  0, -1], [-1,  4,  1, -1],
       [ 5,  7, -1,  2], [ 6,  8,  5,  3], [-1,  9,  6,  4],
       [10, 12, -1,  7], [11, 13, 10,  8], [-1, 14, 11,  9],
       [15, -1, -1, 12], [16, -1, 15, 13], [-1, -1, 16, 14]])
>>> graph.link_dirs_at_node 
array([[-1, -1,  0,  0], [-1, -1,  1,  0], [ 0, -1,  1,  0],
       [-1, -1,  0,  1], [-1, -1,  1,  1], [ 0, -1,  1,  1],
       [-1, -1,  0,  1], [-1, -1,  1,  1], [ 0, -1,  1,  1],
       [-1,  0,  0,  1], [-1,  0,  1,  1], [ 0,  0,  1,  1]], dtype=int8)
>>> graph.nodes_at_link 
array([[ 0,  1], [ 1,  2], [ 0,  3], [ 1,  4], [ 2,  5],
       [ 3,  4], [ 4,  5], [ 3,  6], [ 4,  7], [ 5,  8],
       [ 6,  7], [ 7,  8], [ 6,  9], [ 7, 10], [ 8, 11],
       [ 9, 10], [10, 11]])
>>> graph.links_at_patch 
array([[ 3,  5,  2,  0], [ 4,  6,  3,  1],
       [ 8, 10,  7,  5], [ 9, 11,  8,  6],
       [13, 15, 12, 10], [14, 16, 13, 11]])
>>> graph.nodes_at_patch 
array([[ 4,  3,  0,  1], [ 5,  4,  1,  2],
       [ 7,  6,  3,  4], [ 8,  7,  4,  5],
       [10,  9,  6,  7], [11, 10,  7,  8]])

Define a graph of connected nodes.

Parameters

mesh (Dataset) – xarray Dataset that defines the topology in ugrid format.

property dx#
property dy#
property origin#
property spacing#