def METHOD_NAME(grid_map, z, iz, ix, iy, std):
    # predicted range
    x = ix * grid_map.xy_resolution + grid_map.min_x
    y = iy * grid_map.xy_resolution + grid_map.min_y
    d = math.hypot(x - z[iz, 1], y - z[iz, 2])
    # likelihood
    pdf = norm.pdf(d - z[iz, 0], 0.0, std)
    return pdf