如何减少 Cython 编译代码与 Python 的交互

Question

我试图通过用 Cython 编译为 C 来减少计算量特别大的 Python 代码。令人惊讶的是，我在加速它方面几乎没有成功。使用原始 Python 模块，代码运行大约 45 秒，使用 Cython 编译模块运行大约 45 秒。

使用 annotate=True 编译时，我留下了一大堆黄色（大概）线条，表明仍然存在大量 Python 交互。

我已通过关闭 boundscheck (False) 和 cdivision (True) 来对此作出回应。这没有效果。以下代码片段是该模块的摘录，它坚持与 Python 进行交互。为什么是这样？这里没有什么需要与任何预先存在的 Python 模块交互，都是非常简单的算术？

cpdef float __distance_between(point1, point2)  except? -2:
    return ((point1[0] - point2[0]) ** 2 + (point1[1] - point2[1]) ** 2) ** (1/2)

point1 和 point2 是 Python 列表，每个列表包含 2 doubles 例如：[611811.997, -871083.372] 结果 C-代码是Cython 为代码段中的 return 行生成的代码如下：

+05: cpdef float __distance_between(point1, point2)  except? -2:
+06:     return ((point1[0] - point2[0]) ** 2 + (point1[1] - point2[1]) ** 2)**(1/2)
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我怎样才能更好地优化代码或编译以使这个片段独立于 Python？

此模块中还有许多其他行都呈现为黄色，但从这个问题开始可能会让我更好地理解如何解决其余部分。

Answer 1

您还没有 cdef编辑任何变量；你知道它们是 float，Cython 不知道。告诉它。

cpdef float __distance_between((double, double)point1, (double, double)point2)  except? -2:
    return ((point1[0] - point2[0]) ** 2 + (point1[1] - point2[1]) ** 2) ** (1/2)

如何减少 Cython 编译代码与 Python 的交互

How to reduce Cython compiled code's interaction with Python

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