Exemplo n.º 1
0
class BaseFitter(object):
    __doc__ = _COMMON_DOC + """

    Parameters
    ----------
    data : array-like
    model : lmfit.Model
        optional initial Model to use, maybe be set or changed later
    """ + _COMMON_EXAMPLES_DOC

    def __init__(self, data, model=None, **kwargs):
        self._data = data
        self.kwargs = kwargs

        # GUI-based subclasses need a default value for the menu of models,
        # and so an arbitrary default is applied here, for uniformity
        # among the subclasses.
        if model is None:
            model = ExponentialModel
        self.model = model

    def _on_model_value_change(self, name, value):
        self.model = value

    def _on_fit_button_click(self, b):
        self.fit()

    def _on_guess_button_click(self, b):
        self.guess()

    @property
    def data(self):
        return self._data

    @data.setter
    def data(self, value):
        self._data = value

    @property
    def model(self):
        return self._model

    @model.setter
    def model(self, value):
        if callable(value):
            model = value()
        else:
            model = value
        self._model = model
        self.current_result = None
        self._current_params = model.make_params()

        # Use these to evaluate any Parameters that use expressions.
        self.asteval = Interpreter()
        self.namefinder = NameFinder()

        self._finalize_model(value)

        self.guess()

    def _finalize_model(self, value):
        # subclasses optionally override to update display here
        pass

    @property
    def current_params(self):
        """Each time fit() is called, these will be updated to reflect
        the latest best params. They will be used as the initial guess
        for the next fit, unless overridden by arguments to fit()."""
        return self._current_params

    @current_params.setter
    def current_params(self, new_params):
        # Copy contents, but retain original params objects.
        for name, par in new_params.items():
            self._current_params[name].value = par.value
            self._current_params[name].expr = par.expr
            self._current_params[name].vary = par.vary
            self._current_params[name].min = par.min
            self._current_params[name].max = par.max

        # Compute values for expression-based Parameters.
        self.__assign_deps(self._current_params)
        for _, par in self._current_params.items():
            if par.value is None:
                self.__update_paramval(self._current_params, par.name)

        self._finalize_params()

    def _finalize_params(self):
        # subclasses can override this to pass params to display
        pass

    def guess(self):
        count_indep_vars = len(self.model.independent_vars)
        guessing_successful = True
        try:
            if count_indep_vars == 0:
                guess = self.model.guess(self._data)
            elif count_indep_vars == 1:
                key = self.model.independent_vars[0]
                val = self.kwargs[key]
                d = {key: val}
                guess = self.model.guess(self._data, **d)
            self.current_params = guess
        except NotImplementedError:
            guessing_successful = False
        return guessing_successful

    def __assign_deps(self, params):
        # N.B. This does not use self.current_params but rather
        # new Parameters that are being built by self.guess().
        for name, par in params.items():
            if par.expr is not None:
                par.ast = self.asteval.parse(par.expr)
                check_ast_errors(self.asteval.error)
                par.deps = []
                self.namefinder.names = []
                self.namefinder.generic_visit(par.ast)
                for symname in self.namefinder.names:
                    if (symname in self.current_params
                            and symname not in par.deps):
                        par.deps.append(symname)
                self.asteval.symtable[name] = par.value
                if par.name is None:
                    par.name = name

    def __update_paramval(self, params, name):
        # N.B. This does not use self.current_params but rather
        # new Parameters that are being built by self.guess().
        par = params[name]
        if getattr(par, 'expr', None) is not None:
            if getattr(par, 'ast', None) is None:
                par.ast = self.asteval.parse(par.expr)
            if par.deps is not None:
                for dep in par.deps:
                    self.__update_paramval(params, dep)
            par.value = self.asteval.run(par.ast)
            out = check_ast_errors(self.asteval.error)
            if out is not None:
                self.asteval.raise_exception(None)
        self.asteval.symtable[name] = par.value

    def fit(self, *args, **kwargs):
        "Use current_params unless overridden by arguments passed here."
        guess = dict(self.current_params)
        guess.update(self.kwargs)  # from __init__, e.g. x=x
        guess.update(kwargs)
        self.current_result = self.model.fit(self._data, *args, **guess)
        self.current_params = self.current_result.params
Exemplo n.º 2
0
class BaseFitter(object):
    __doc__ = _COMMON_DOC + """

    Parameters
    ----------
    data : array-like
    model : lmfit.Model
        optional initial Model to use, maybe be set or changed later
    """ + _COMMON_EXAMPLES_DOC

    def __init__(self, data, model=None, **kwargs):
        self._data = data
        self.kwargs = kwargs

        # GUI-based subclasses need a default value for the menu of models,
        # and so an arbitrary default is applied here, for uniformity
        # among the subclasses.
        if model is None:
            model = ExponentialModel
        self.model = model

    def _on_model_value_change(self, name, value):
        self.model = value

    def _on_fit_button_click(self, b):
        self.fit()

    def _on_guess_button_click(self, b):
        self.guess()

    @property
    def data(self):
        return self._data

    @data.setter
    def data(self, value):
        self._data = value

    @property
    def model(self):
        return self._model

    @model.setter
    def model(self, value):
        if callable(value):
            model = value()
        else:
            model = value
        self._model = model
        self.current_result = None
        self._current_params = model.make_params()

        # Use these to evaluate any Parameters that use expressions.
        self.asteval = Interpreter()
        self.namefinder = NameFinder()

        self._finalize_model(value)

        self.guess()

    def _finalize_model(self, value):
        # subclasses optionally override to update display here
        pass

    @property
    def current_params(self):
        """Each time fit() is called, these will be updated to reflect
        the latest best params. They will be used as the initial guess
        for the next fit, unless overridden by arguments to fit()."""
        return self._current_params

    @current_params.setter
    def current_params(self, new_params):
        # Copy contents, but retain original params objects.
        for name, par in new_params.items():
            self._current_params[name].value = par.value
            self._current_params[name].expr = par.expr
            self._current_params[name].vary = par.vary
            self._current_params[name].min = par.min
            self._current_params[name].max = par.max

        # Compute values for expression-based Parameters.
        self.__assign_deps(self._current_params)
        for _, par in self._current_params.items():
            if par.value is None:
                self.__update_paramval(self._current_params, par.name)

        self._finalize_params()

    def _finalize_params(self):
        # subclasses can override this to pass params to display
        pass

    def guess(self):
        count_indep_vars = len(self.model.independent_vars)
        guessing_successful = True
        try:
            if count_indep_vars == 0:
                guess = self.model.guess(self._data)
            elif count_indep_vars == 1:
                key = self.model.independent_vars[0]
                val = self.kwargs[key]
                d = {key: val}
                guess = self.model.guess(self._data, **d)
            self.current_params = guess
        except NotImplementedError:
            guessing_successful = False
        return guessing_successful

    def __assign_deps(self, params):
        # N.B. This does not use self.current_params but rather
        # new Parameters that are being built by self.guess().
        for name, par in params.items():
            if par.expr is not None:
                par.ast = self.asteval.parse(par.expr)
                check_ast_errors(self.asteval.error)
                par.deps = []
                self.namefinder.names = []
                self.namefinder.generic_visit(par.ast)
                for symname in self.namefinder.names:
                    if (symname in self.current_params and symname not in
                            par.deps):
                        par.deps.append(symname)
                self.asteval.symtable[name] = par.value
                if par.name is None:
                    par.name = name

    def __update_paramval(self, params, name):
        # N.B. This does not use self.current_params but rather
        # new Parameters that are being built by self.guess().
        par = params[name]
        if getattr(par, 'expr', None) is not None:
            if getattr(par, 'ast', None) is None:
                par.ast = self.asteval.parse(par.expr)
            if par.deps is not None:
                for dep in par.deps:
                    self.__update_paramval(params, dep)
            par.value = self.asteval.run(par.ast)
            out = check_ast_errors(self.asteval.error)
            if out is not None:
                self.asteval.raise_exception(None)
        self.asteval.symtable[name] = par.value

    def fit(self, *args, **kwargs):
        "Use current_params unless overridden by arguments passed here."
        guess = dict(self.current_params)
        guess.update(self.kwargs)  # from __init__, e.g. x=x
        guess.update(kwargs)
        self.current_result = self.model.fit(self._data, *args, **guess)
        self.current_params = self.current_result.params