TypeError: 'Scene' object is not iterable

[Ginko2501]

Hi,

I was defining custom @ti.data_oriented and encountered this problem. Here is my code

@ti.data_oriented
class Scene:

def __init__(self, dt):
    # spheres
    self.num_sphere = ti.field(dtype=ti.i32, shape=())
    self.spheres = Sphere.field(shape=(100,))
    
    # particles in local coordinates
    self.num_pt = ti.field(dtype=ti.i32, shape=())
    self.particles = ti.Vector.field(2, shape=(10000), dtype=ti.f32) 
    self.indecies = ti.field(dtype=ti.i32, shape=(10000))
    
     self.init_sphere(self, vec2(0,0), 0.5)

def init_sphere(self, o, r, R=vec2(1,0), v=vec2(0,0), ω=0, m=1, I=None, size=None):
    """Initialize a sphere"""
    self.spheres[self.num_sphere[None]].init(o, r, R, v, ω, m, I, size)
    self.num_sphere[None] += 1

This is what I got

File "c:\Zichen\Cornell\spring2023\CS5643\SimSDF\scene.py", line 24, in f
self.init_sphere(self, vec2(0,0), 0.5)
File "c:\Zichen\Cornell\spring2023\CS5643\SimSDF\scene.py", line 30, in init_sphere
self.spheres.o[0] = o
File "C:\Users\ziche\anaconda3\envs\sim-sdf\lib\site-packages\taichi\lang\util.py", line 311, in wrapped
return func(*args, **kwargs)
File "C:\Users\ziche\anaconda3\envs\sim-sdf\lib\site-packages\taichi\lang\matrix.py", line 1404, in setitem
self[key]._set_entries(value)
File "C:\Users\ziche\anaconda3\envs\sim-sdf\lib\site-packages\taichi\lang\util.py", line 311, in wrapped
return func(*args, **kwargs)
File "C:\Users\ziche\anaconda3\envs\sim-sdf\lib\site-packages\taichi\lang\matrix.py", line 453, in _set_entries
value = list(value)
TypeError: 'Scene' object is not iterable

However, I can self.spheres[self.num_sphere[None]].init(o, r, R, v, ω, m, I, size) with no problem directly in init or in my main.py. So I am not sure why this is happening.

[neozhaoliang]

Hi @Ginko2501 in the code

self.init_sphere(self, vec2(0,0), 0.5)

You don't need to pass self as the first argument here, you should use

self.init_sphere(vec2(0,0), 0.5)

Maybe you need to understand how self works in Python's class, for example: https://www.pythonmorsels.com/what-is-self/