大约有 40,000 项符合查询结果（耗时：0.0321秒） [XML]
Pandas aggregate count distinct
...aframe, then grouped to ~2M
%time _=g.agg({"id": lambda x: x.nunique()})
CPU times: user 3min 3s, sys: 2.94 s, total: 3min 6s
Wall time: 3min 20s
%time _=g.agg({"id": pd.Series.nunique})
CPU times: user 3min 2s, sys: 2.44 s, total: 3min 4s
Wall time: 3min 18s
%time _=g.agg({"id": "nunique"})
CPU...
谁在争抢UGC - 资讯 - 清泛网 - 专注C/C++及内核技术
...播客识别出侵权视频，保护原创版权。
由于网络媒体的定位及其受众的广泛性，目前采用UGC模式的网站不约而同地将娱乐作为其业务的主导方向。而从媒体的本质来说，真正能与门户网站进行竞争的仍然是与民生密切相关的新...
Why does the order of the loops affect performance when iterating over a 2D array?
... x[1][0] etc...
Meaning that you're hitting them all in order. Now look at the 1st version. You're doing:
x[0][0]
x[1][0]
x[2][0]
x[0][1]
...
How to turn off INFO logging in Spark?
I installed Spark using the AWS EC2 guide and I can launch the program fine using the bin/pyspark script to get to the spark prompt and can also do the Quick Start quide successfully.
...
What is the purpose of XORing a register with itself? [duplicate]
...ad dependency on eax, so the execution time is the same" The processor actually does even better: it just executes a register rename internally, and doesn't even do anything at all with eax.
– kquinn
Sep 8 '09 at 22:16
...
Command-line Tool to find Java Heap Size and Memory Used (Linux)?
...tion which options of jstat one should use in order to verify just the overall memory usage of a JVM? Let's say you start the JVM with Xms=4g and Xmx=4g and you want to see, how much memory of that is already used?
– basZero
Feb 5 '14 at 9:44
...
Queue.Queue vs. collections.deque
...nd collections.deque serve different purposes. Queue.Queue is intended for allowing different threads to communicate using queued messages/data, whereas collections.deque is simply intended as a datastructure. That's why Queue.Queue has methods like put_nowait(), get_nowait(), and join(), whereas co...
What are the main uses of yield(), and how does it differ from join() and interrupt()?
...m a little bit confused about the use of yield() method in Java, specifically in the example code below. I've also read that yield() is 'used to prevent execution of a thread'.
...
When should the volatile keyword be used in C#?
...ors and making
them synchronize main memory with their caches".
Actually, that last bit is a lie. The true semantics of volatile reads
and writes are considerably more complex than I've outlined here; in
fact they do not actually guarantee that every processor stops what it
is doing and...
How to keep the console window open in Visual C++?
...ause") or any other garbage. Changing this works.
– Callat
Apr 22 '16 at 16:08
Ctrl+F5 means 'Start Without Debugging'...