fastwater.general.meshTools module

Functions for the manipulation and interpolation of data on unstructured triangular meshes.

fastwater.general.meshTools.getBarycentricWeights(p1, p2, p3, p)

Calculate Barycentric weights for point p within triangle (p1,p2,p3)

Parameters

• p1 (list[ float ]) – [x, y] coordinates for triangle corner point p1.

• p2 (list[ float ]) – [x, y] coordinates for triangle corner point p2.

• p3 (list[ float ]) – [x, y] coordinates for triangle corner point p3.

• p (list[ float ]) – [x, y] coordinates for point p within triangle (p1, p2, p3).

Returns

[w1, w2 ,w3] – barycentric weights for triangle (p1, p2, p3).

Return type

list

fastwater.general.meshTools.getCentroidWeights(p1, p2, p3)

Calculate Barycentric weights for interpolating data on the centroid of the triange defined by the points (p1, p2, p3)

Parameters

• p1 (list[ float ]) – [x, y] coordinates for triangle corner point p1.

• p2 (list[ float ]) – [x, y] coordinates for triangle corner point p2.

• p3 (list[ float ]) – [x, y] coordinates for triangle corner point p3.

Returns

centroidWghts – centroid Barycentric weights for triangle (p1, p2, p3).

Return type

list[ float ]

fastwater.general.meshTools.getElemAroundLoc(meshx, meshy, meshElems, LocX, LocY, nLys=1)

fastwater.general.meshTools.getElemNodes(meshx, meshy, elems, LocX, LocY)

fastwater.general.meshTools.getNearestNode(meshX, meshY, locX, locY, nLys=1)

fastwater.general.meshTools.getNodesAroundNode(node, edges)

fastwater.general.meshTools.getNodesWeights(meshx, meshy, elems, LocX, LocY)

Extract the information required to interpolate mesh data onto a specific location defined by the point (LocX, LocY)

Parameters

• meshx (numpy.array, float) – mesh nodes x coordinate values.

• meshy (numpy.array, float) – mesh nodes y coordinate values.

• elems (numpy.ndarray, int) – mesh elements defninition matrix (nElems, 3).

• LocX (float) – x coordinate of location of interest.

• LocY (flaat) – y coordinate of location of interest.

Returns

• NNodes (list[ int ]) – node indices of triangular element corner points.

• NWghts (list[ float ]) – Barycentric weighting values for triangular element corner points.

• NLocs (list[ list ]) – list of the triangular element corner point locations (p1[x,y], p2[x,y] ,p3[x,y]).

fastwater.general.meshTools.getTriangleArea(p1, p2, p3)

Calculate area of the triangle defined by the points (p1, p2, p3)

Parameters

• p1 (list[ float ]) – [x, y] coordinates for triangle corner point p1.

• p2 (list[ float ]) – [x, y] coordinates for triangle corner point p2.

• p3 (list[ float ]) – [x, y] coordinates for triangle corner point p3.

Returns

area – the area of the triangle (p1, p2, p3).

Return type

float

fastwater.general.meshTools.getTriangleCentroid(p1, p2, p3)

Calculate the centroid location for the triangle defined by the points (p1, p2, p3)

Parameters

• p1 (list[ float ]) – [x, y] coordinates for triangle corner point p1.

• p2 (list[ float ]) – [x, y] coordinates for triangle corner point p2.

• p3 (list[ float ]) – [x, y] coordinates for triangle corner point p3.

Returns

centroid – centroid location for the triangle (p1, p2, p3).

Return type

list[ float ]

fastwater.general.meshTools.gradation2meshDensity(gradRaster)

fastwater.general.meshTools.gradation2numElems(gradRaster, dx, dy)

fastwater.general.meshTools.gradientAtNode(node, nodes, nodesX, nodesY, var)

fastwater.general.meshTools.interpTriangle(p1, p2, p3, p, v1, v2, v3)

Use Barycentic weighting to interpolate variable data (v1, v2, v3) on triangle corner points (p1, p2, p3) onto the location p.

Parameters

• p1 (list[ float ]) – [x, y] coordinates for triangle corner point p1.

• p2 (list[ float ]) – [x, y] coordinates for triangle corner point p2.

• p3 (list[ float ]) – [x, y] coordinates for triangle corner point p3.

• p (list[ float ]) – [x, y] coordinates for point p.

• v1 (float) – variable value at point p1.

• v2 (floate) – variable value at point p2.

• v3 (float) – variable value at point p3.

Returns

vp – interpolated variable value at point p.

Return type

float

fastwater.general.meshTools.isInsideTriangle(p1, p2, p3, p)

Determine if the point p lies with in the triangle defeind by (p1, p2, p3)

Parameters

• p1 (list[ float ]) – [x, y] coordinates for triangle corner point p1.

• p2 (list[ float ]) – [x, y] coordinates for triangle corner point p2.

• p3 (list[ float ]) – [x, y] coordinates for triangle corner point p3.

• p (list[ float ]) – [x, y] coordinates for point p.

Returns

isInside – True/False flag defining whether p is inside (p1, p2, p3).

Return type

bool

fastwater.general.meshTools.meshDensity(areas)

fastwater.general.meshTools.weightsMatrix(nodeWghts, nStps)