fedoo.Mesh.find_nodes

Mesh.find_nodes(selection_criterion: str, value: float = 0, tol: float = 1e-06) → ndarray[int]

Return a list of nodes from a given selection criterion

Parameters:

• selection_criterion (str) –

  selection criterion used to select the returned nodes. Possibilities are:

  • ’X’: select nodes with a specified x coordinate value

  • ’Y’: select nodes with a specified y coordinate value

  • ’Z’: select nodes with a specified z coordinate value

  • ’XY’ : select nodes with specified x and y coordinates values

  • ’XZ’ : select nodes with specified x and z coordinates values

  • ’YZ’ : select nodes with specified y and z coordinates values

  • ’Point’: select nodes at a given position

  • ’Distance’: select nodes at a given distance from a point

  • Arbitrary str expression

• value (scalar or list of scalar of numpy array) –

  • if selection_criterion in [‘X’, ‘Y’, ‘Z’] value should be a scalar

  • if selection_criterion in [‘XY’, ‘XZ’, ‘YZ’] value should be a list (or array) containing 2 scalar which are the coordinates in the given plane

  • if selection_criterion == ‘point’, value should be a list containing 2 scalars (for 2D problem) or 3 scalars (for 3D problems) which are the coordinates of the point.

  • if selection_criterion == ‘distance’, value is a tuple where value[0] contains the coordinate (list of int) of the point from which the distance is computed and value[1] the distance.

  • value is ignored if selection_criterion is an arbitrary expression

• tol (float) – Tolerance of the given criterion. Ignored if selection_criterion is an arbitrary expression

Return type:

List of node index

Notes

Aritrary expressions allow the use of “and” and “or” logical operator, parenthesis, and the following compareason operators: “>”, “<”, “<=”, “>=”, “==”, “!=”. The coordinates ‘X’, ‘Y’ and ‘Z’ are available in the expression. In case of arbitrary expression, value and tol parameters are ignored

Example

Create a one element mesh from a 2d mesh in a 3d space:

>>> import fedoo as fd
>>> mesh = fd.mesh.disk_mesh()
>>> mesh.find_nodes("(X>0.2 and X<0.5) or Y>0.4")