# BasisFunction¶

class dolfin.cpp.fem.BasisFunction(*args)

Bases: ufc.ufc.function

This class represents a finite element basis function. It can be used for computation of basis function values and derivatives.

Evaluation of basis functions is also possible through the use of the functions evaluate_basis and evaluate_basis_derivatives available in the FiniteElement class. The BasisFunction class relies on these functions for evaluation but also implements the ufc::function interface which allows evaluate_dof to be evaluated for a basis function (on a possibly different element).

Create basis function with given index on element on given cell

Arguments
index (int)
The index of the basis function.
element (FiniteElement)
The element to create basis function on.
cell (ufc::cell)
The cell.
eval()

Evaluate basis function at given point

Arguments
values (float)
The values of the function at the point.
x (float)
The coordinates of the point.
eval_derivatives()

Evaluate all order n derivatives at given point

Arguments
values (float)
The values of derivatives at the point.
x (float)
The coordinates of the point.
n (int)
The order of derivation.
thisown

The membership flag