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有关 list 内存释放的小技巧

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Jun 07, 2016 pm 03:41 PM

listpythonMemorySkillfreed

用python也有一段时间了，有了不少体会。平时老写要求效率很高的程序，发现python真的很不错。但是对于超大list的数据，内存经常需要立即释放。我总结了一些有关性能的技巧，看看大家能不能用上。 1。大数据量的list，要进行局部元素删除，尽量避免用del随

用python也有一段时间了，有了不少体会。平时老写要求效率很高的程序，发现python真的很不错。但是对于超大list的数据，

内存经常需要立即释放。我总结了一些有关性能的技巧，看看大家能不能用上。

1。大数据量的list，要进行局部元素删除，尽量避免用del随机删除，非常影响性能，如果删除量很大，不如直接新建list，

然后用下面的方法释放清空旧list。

2。对于一般性数据量超大的list，快速清空释放内存，可直接用 a = [] 来释放。其中a为list。

3。对于作为函数参数的list，用上面的方法是不行的，因为函数执行完后，list长度是不变的，

但是可以这样在函数中释放一个参数list所占内存： del a[:]，速度很快，也彻底：）

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