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# root(method=’broyden2’)

`scipy.optimize.``root`(fun, x0, args=(), method='broyden2', tol=None, callback=None, options={})

  See also

  For documentation for the rest of the parameters, see `scipy.optimize.root`

  Options: | nit : int, optional Number of iterations to make. If omitted (default), make as many as required to meet tolerances. disp : bool, optional Print status to stdout on every iteration. maxiter : int, optional Maximum number of iterations to make. If more are needed to meet convergence, NoConvergence is raised. ftol : float, optional Relative tolerance for the residual. If omitted, not used. fatol : float, optional Absolute tolerance (in max-norm) for the residual. If omitted, default is 6e-6. xtol : float, optional Relative minimum step size. If omitted, not used. xatol : float, optional Absolute minimum step size, as determined from the Jacobian approximation. If the step size is smaller than this, optimization is terminated as successful. If omitted, not used. tol_norm : function(vector) -> scalar, optional Norm to use in convergence check. Default is the maximum norm. line_search : {None, ‘armijo’ (default), ‘wolfe’}, optional Which type of a line search to use to determine the step size in the direction given by the Jacobian approximation. Defaults to ‘armijo’. jac_options : dict, optional Options for the respective Jacobian approximation. alpha : float, optional Initial guess for the Jacobian is (-1/alpha). reduction_method : str or tuple, optional Method used in ensuring that the rank of the Broyden matrix stays low. Can either be a string giving the name of the method, or a tuple of the form `(method, param1, param2, ...)` that gives the name of the method and values for additional parameters. Methods available: `restart`: drop all matrix columns. Has no extra parameters. `simple`: drop oldest matrix column. Has no extra parameters. `svd`: keep only the most significant SVD components. Extra parameters: `to_retain`: number of SVD components to retain when rank reduction is done. Default is `max_rank - 2`. max_rank : int, optional Maximum rank for the Broyden matrix. Default is infinity (ie., no rank reduction).