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import functools |
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from ... import problems |
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class SolowModel(problems.IVP): |
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""" |
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Class representing a generic Solow growth model. |
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Attributes |
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---------- |
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equilibrium_capital : function |
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Equilibrium value for capital (per unit effective labor). |
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intensive_output : function |
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Output (per unit effective labor supply). |
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params : dict(str: float) |
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Dictionary of model parameters. |
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""" |
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def __init__(self, f, k_star, params): |
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""" |
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Initialize an instance of the SolowModel class. |
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Parameters |
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---------- |
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f : function |
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Output (per unit effective labor supply). |
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k_star : function |
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Equilibrium value for capital (per unit effective labor). |
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params : dict(str: float) |
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Dictionary of model parameters. |
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""" |
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rhs = self._rhs_factory(f) |
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self._equilbrium_capital = k_star |
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self._intensive_output = f |
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super(SolowModel, self).__init__(self._initial_condition, 1, 1, params, rhs) |
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@property |
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def equilibrium_capital(self): |
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return self._equilbrium_capital |
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@property |
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def intensive_output(self): |
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return self._intensive_output |
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@staticmethod |
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def _initial_condition(t, k, k0, **params): |
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return [k - k0] |
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@classmethod |
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def _solow_model(cls, t, k, f, delta, g, n, s, **params): |
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return [s * f(k, **params) - (g + n + delta) * k] |
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@classmethod |
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def _rhs_factory(cls, f): |
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return functools.partial(cls._solow_model, f=f) |
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davidrpugh /
pyCollocation
