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Combine two columns of text in pandas dataframe
...[252]: (200000, 2)
UPDATE: new timings using Pandas 0.19.0
Timing without CPU/GPU optimization (sorted from fastest to slowest):
In [107]: %timeit df['Year'].astype(str) + df['quarter']
10 loops, best of 3: 131 ms per loop
In [106]: %timeit df['Year'].map(str) + df['quarter']
10 loops, best of 3: ...
What does “dereferencing” a pointer mean?
...igher level libraries and applications, but code for OSes, device drivers, etc. may need to rely on behaviour left undefined by the C or C++ Standard, that is nevertheless well defined by their specific implementation or hardware.
...
大数据时代的数据化运营 - 资讯 - 清泛网 - 专注C/C++及内核技术
...下，我们在运营中看到可以获得有效数据的原始数据不是问题，去除无效和虚假的数据才是关键。
相信做发行的同行都知道，在实践中，会遇到通过某些渠道或者是CPS，或者是广告渠道，他们一定会有大量的虚假的数据在里面...
NSOperation vs Grand Central Dispatch
... answer. All the benefits of NSOperationQueue (dependencies, debugability, etc.) apply to block operations too.
– BJ Homer
Apr 30 '12 at 4:40
4
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Async/await vs BackgroundWorker
...on the thread only when the method is active. You can use Task.Run to move CPU-bound work to a background thread, but a background thread doesn't help with a process that's just waiting for results to become available.
The async-based approach to asynchronous programming is preferable to existing ap...
Async/Await vs Threads
...read is a separate stream of execution that can run with its own variables etc. where - given sufficient hardware - execution occurs in parallel to the main thread.
If you have a GUI application that is going to download a single file and then do something with that file when its downloaded - I'd i...
TCP 的那些事儿（下） - 更多技术 - 清泛网 - 专注C/C++及内核技术
... 算法
但是上面的这个算法在重传的时候会出有一个终极问题——你是用第一次发数据的时间和ack回来的时间做RTT样本值，还是用重传的时间和ACK回来的时间做RTT样本值？
这个问题无论你选那头都是按下葫芦起了瓢。 如下图所...
Extension · App Inventor 2 中文网
...
Methods
RandomNumCode(length)
返回一个指定位数随机数字码。
SendSms(phoneNumber,signName,templateCode,templateParam)
发送短信。参数：手机号，签名名称，模板CODE，模板参数JSON
BaiduPan
Component for Baidu...
Why is IntelliJ 13 IDEA so slow after upgrading from version 12?
...ely to need anytime soon (eg. support for Mecurical, internationalization, etc). It took the startup time from literally MINUTES, to about 10-15 seconds). The general performance seems to be much snappier now as well. Oddly enough, the memory footprint didn't change much, in my case, staying around...
The point of test %eax %eax [duplicate]
... the operands (registers) as they are and just set/unset specific internal CPU flags like the zero-flag (ZF). You can think at the ZF as a true/false boolean flag that resides inside the CPU.
in this particular case, TEST instruction performs a bitwise logical AND, discards the actual result and s...