Interpolant

class pybamm.Interpolant(x: ndarray | Sequence[ndarray], y: ndarray, children: Sequence[Symbol] | Time, name: str | None = None, interpolator: str | None = 'linear', extrapolate: bool = True, entries_string: str | None = None)

Interpolate data in 1D, 2D, or 3D. Interpolation in 3D requires the input data to be on a regular grid (as per scipy.interpolate.RegularGridInterpolator).

Parameters:

• x (iterable of numpy.ndarray) – The data point coordinates. If 1-D, then this is an array(s) of real values. If, 2D or 3D interpolation, then this is to ba a tuple of 1D arrays (one for each dimension) which together define the coordinates of the points.

• y (numpy.ndarray) – The values of the function to interpolate at the data points. In 2D and 3D, this should be a matrix of two and three dimensions respectively.

• children (iterable of pybamm.Symbol) – Node(s) to use when evaluating the interpolant. Each child corresponds to an entry of x

• name (str, optional) – Name of the interpolant. Default is None, in which case the name “interpolating function” is given.

• interpolator (str, optional) – Which interpolator to use. Can be “linear”, “cubic”, or “pchip”. Default is “linear”. For 3D interpolation, only “linear” an “cubic” are currently supported.

• extrapolate (bool, optional) – Whether to extrapolate for points that are outside of the parametrisation range, or return NaN (following default behaviour from scipy). Default is True. Generally, it is best to set this to be False for 3D interpolation due to the higher potential for errors in extrapolation.

Extends: pybamm.expression_tree.functions.Function

set_id()

See pybamm.Symbol.set_id().

to_json()

Method to serialise an Interpolant object into JSON.