Functions

class pybamm.Function(function, *children, name=None, derivative='autograd', differentiated_function=None)

A node in the expression tree representing an arbitrary function

Parameters:

• function (method) – A function can have 0 or many inputs. If no inputs are given, self.evaluate() simply returns func(). Otherwise, self.evaluate(t, y, u) returns func(child0.evaluate(t, y, u), child1.evaluate(t, y, u), etc).
• children (pybamm.Symbol) – The children nodes to apply the function to
• derivative (str, optional) – Which derivative to use when differentiating (“autograd” or “derivative”). Default is “autograd”.
• differentiated_function (method, optional) – The function which was differentiated to obtain this one. Default is None.
• **Extends (** pybamm.Symbol) –

diff(variable)

See pybamm.Symbol.diff().

evaluate(t=None, y=None, y_dot=None, inputs=None, known_evals=None)

See pybamm.Symbol.evaluate().

evaluates_on_edges(dimension)

See pybamm.Symbol.evaluates_on_edges().

get_children_domains(children_list)

Obtains the unique domain of the children. If the children have different domains then raise an error

is_constant()

See pybamm.Symbol.is_constant().

new_copy()

See pybamm.Symbol.new_copy().

class pybamm.SpecificFunction(function, child)

Parent class for the specific functions, which implement their own diff operators directly.

Parameters:

• function (method) – Function to be applied to child
• child (pybamm.Symbol) – The child to apply the function to

class pybamm.Cos(child)

Cosine function

pybamm.cos(child)

Returns cosine function of child.

class pybamm.Cosh(child)

Hyberbolic cosine function

pybamm.cosh(child)

Returns hyperbolic cosine function of child.

class pybamm.Exponential(child)

Exponential function

pybamm.exp(child)

Returns exponential function of child.

class pybamm.Log(child)

Logarithmic function

pybamm.log(child, base='e')

Returns logarithmic function of child (any base, default ‘e’).

pybamm.max(child)

Returns max function of child. Not to be confused with pybamm.maximum(), which returns the larger of two objects.

pybamm.min(child)

Returns min function of child. Not to be confused with pybamm.minimum(), which returns the smaller of two objects.

class pybamm.Sin(child)

Sine function

pybamm.sin(child)

Returns sine function of child.

class pybamm.Sinh(child)

Hyperbolic sine function

pybamm.sinh(child)

Returns hyperbolic sine function of child.