Python中的数据局部性优化

时间:2015-11-03 10:17:46

标签: python numpy memory

问题在于如何在Python中为这个类分配内存,而问题更多的是出于好奇而不是现实生活价值。

以下后处理类处理大量数据(numpy数组)。这是实际代码的简化版本,以使问题可读。基类的共享数据现在替换为characteristic_length变量。

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作为处理内存的python方式的陌生人,我很好奇是否将characteristic_length放在子类中会大大提高性能吗?

基于python文档,我认为派生类实例有一个指向定义基类的地址的指针。如果子类中的查找失败,则在基类中继续。这听起来像使用基类属性来存储派生类共享的数据是非常昂贵的。

在实际应用程序中,共享数据有点大numpy数组,但对所有派生类都是通用的。懒惰,我想避免分别读取每个子类的数据。有关如何有效解决这个问题的任何指示?

1 个答案:

答案 0 :(得分:1)

最简单的解决方案是使numpy数组成为全局数组。如果您想阻止用户修改该数组,可以将writable flag设置为False

或者你可以使它成为Reader类的class属性。

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