pydantic 初始化 numpy ndarray

Question

ndarray使用 pydantic 时如何初始化？
这段代码抛出一个ValueError: The truth value of an array with more than one element is ambiguous. Use a.any() or a.all()

from pydantic.dataclasses import dataclass
import numpy as np

@dataclass
class TestNumpyArray:
    numpyArray: np.ndarray = np.zeros(10)

testNumpyArray = TestNumpyArray()

Answer 1

您需要提供default_factory一个Field声明。

请注意，您不能在 Pydantic 数据类中使用任意类型，因此您可能需要扩展BaseModel：

from pydantic import BaseModel, Field
import numpy as np

class TestNumpyArray(BaseModel):
    numpyArray: np.ndarray = Field(default_factory=lambda: np.zeros(10))

    class Config:
        arbitrary_types_allowed = True

testNumpyArray = TestNumpyArray()

您还可以将非 Pydantic 数据类与dataclasses.field(default_factory=...).