def __init__(self, fun, each, grad_rms):
self.fun = fun<EOL>self.each = each<EOL>self.grad_rms = grad_rms<EOL>self.last_update = <NUM_LIT:0><EOL>
Arguments:
 | ``fun``  --  the function whose arguments must be transformed
 | ``each``  --  update the linear transformation after each 'each'
                 minimizer steps without updates
 | ``grad_rms``  --  only update when the rms value of the gradient
                     (in the original coordinates) is below this
                     threshold