def scale_soma_depth(cell_id, norm_features, df):
    """ 
    Move neuron to soma depth realtive to pia.
    Args:
        cell_id: str
        norm_features: normalized features per node
        df: pandas dataframe containing soma depth per neuron
    """
    # soma depth
    d_fac = df[df['specimen_id']==cell_id]['soma_distance_from_pia'].values[0]
    pos3 = norm_features[:, :3].copy()
    pos3[:, 1] -= d_fac

    norm_features[:, :3] = pos3
    
    return norm_features