def set_solver()

in ridge_sketch.py [0:0]


    def set_solver(self, algo_mode, solver):
        if algo_mode == "auto":
            if solver == "auto":
                solver = "cg"
        else:
            if solver in ["direct", "cg"]:
                raise ValueError(
                    f"Momentum or acceleration are not available for {solver} solver."
                )
            elif solver == "auto":
                solver = "subsample"  # default for accel and mom versions
        return solver