import numpy as np
from numba import jitclass, float64, optional, njit
from numba.types import ListType
from numba.typed import List


@njit(cache=True)
def npv3(a,b,c):
    return np.array((a,b,c),dtype=np.float64)

spec = [
    ('C',               float64),
    ('points',   optional( ListType(float64[:]))  ) ,
]
float_array = float64[:]
@jitclass(spec)
class SampleClass(object):
    def __init__(self):
        self.C =            np.float64(1.0)
        self.points = List.empty_list(float_array)
        self.init_values()

    def init_values(self):
        self.points.append( npv3(0,0,0) )
        self.points.append( npv3(0,0,0) )

    def clear(self):
        self.points.clear()

if __name__ == '__main__':
    sc = SampleClass()
    print("len:",len(sc.points))
    #sc.points.__init__()
    #sc.points.__delitem__(0)
    sc.clear()
    #sc.points.clear()
    #sc.points = List.empty_list( float_array )
    print("len:", len(sc.points))