大约有 36,000 项符合查询结果(耗时:0.0370秒) [XML]

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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...
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std::vector performance regression when enabling C++11

...a.out' (10 runs): 35.426793 task-clock # 0.986 CPUs utilized ( +- 1.75% ) 4 context-switches # 0.116 K/sec ( +- 5.69% ) 0 CPU-migrations # 0.006 K/sec ( +- 66.67...
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Why aren't variable-length arrays part of the C++ standard?

...loca(), I didn't really care that the memory was physically located on the cpu stack, just that it came from some stack allocator that didn't incur slow trips to the general heap. So I have a per-thread object that owns some memory from which it can push/pop variable sized buffers. On some platfor...
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从估值5千万到一无所有 90后的他感觉梦境一场 - 资讯 - 清泛网 - 专注C/C++...

...O2O现在还没到风口。宠物行业的根本不在这里,这是源头问题。”与此同时,他对爱狗团的方向也进行了调整。夏军原本做的是宠物O2O,类似于美团的团购模式,将买家导入到线下的商户。而他放弃了O2O做法,现在做的模式不像...
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Is a LINQ statement faster than a 'foreach' loop?

...parison. Re PLINQ; parallelism may reduce the elapsed time, but the total CPU time will usually increase a little due to the overheads of thread management etc. share | improve this answer ...
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What does a just-in-time (JIT) compiler do?

...ime, as it's called) into a form that's usually faster, typically the host CPU's native instruction set. A JIT has access to dynamic runtime information whereas a standard compiler doesn't and can make better optimizations like inlining functions that are used frequently. This is in contrast to a t...
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How to Calculate Execution Time of a Code Snippet in C++

...linux-gnu/libstdc++.so.6: version GLIBCXX_3.4.19 not found (required by ../cpu_2d/g500) – user9869932 Sep 2 '15 at 20:13 ...
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你真的了解熊市有多么可怕吗? - 创意 - 清泛网 - 专注C/C++及内核技术

...巫见大巫了。大盘反弹在1700点后,横了一个月,一个冲高的假突破后,大盘再次杀跌,当时没有人再敢抄底了,因为谁也不敢想底在哪里,十几天下来,大盘已经到了1300,后来大盘出现了又一次的反弹,最后进入了最恐怖的阴...
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What exactly are “spin-locks”?

...lly short, because your thread now has to wait for a preemption to receive CPU time again. Besides, kernel objects are not available in every state of the kernel, such as in an interrupt handler or when paging is not available etc. Spinlocks don't cause preemption but wait in a loop ("spin") till th...
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Eclipse RCP开发桌面程序 - 更多技术 - 清泛网 - 专注C/C++及内核技术

...进依赖项,否则会出错。最开始的时候,就是这么一点小问题,让我浪费了几天时间。   再点击添加必须的插件,自动添加其它的依赖项。   再下一步,设置项目的构建路径,如下图:   下一步,导出我们的...