def Powerlaw(x, n=0.5, K=0.1):
    """Powerlaw model for the stress data

    Note:

    .. math::
       \sigma=K \cdot \dot\gamma^n

    Args:

        K : consistency index [Pa s]
        n : shear thinning index (1 for Newtonian) []

    Returns:
        stress : Shear Stress, [Pa]
    """
    return K * x ** n