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R.exe, Rcmd.exe, Rscript.exe and Rterm.exe: what's the difference?
...efore littler and Rscript.exe, and similarly lingering from old docs and habits..
Rscript.exe is your friend for batch scripts; use it.
For everything else, there's R.exe.
Other than that, as Marek hinted, the reference manual is the wrong one among the six available manuals. Try the Introduction ...
Pandas count(distinct) equivalent
...ARMONTH
201301 2 1 0
201302 1 2 1
After a little bit modify ,yield the result
pd.crosstab(df.YEARMONTH,df.CLIENTCODE).ne(0).sum(1)
Out[197]:
YEARMONTH
201301 2
201302 3
dtype: int64
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Understanding MongoDB BSON Document size limit
...then no problem. But in terms of pure efficiency, you do not want useless bits to take up memory space if you can avoid it (and that goes for RDBMS as well).
– AlexGad
Dec 24 '11 at 16:52
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Is there hard evidence of the ROI of unit testing?
... the fundamental values of agile teams) or lost based on role power of the winning party. Even if the TDD-proponents win based on role power I'd count it as lost.
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MFC 获取当前时间的几种方法总结 - C/C++ - 清泛网 - 专注C/C++及内核技术
...tm_minute = curTime.wMinute;
tmTime.tm_second = curTime.wSecond;
__time64_t curTime_64t = _mktime64(&tmTime);
struct tm st;
st.tm_year = atoi(strTime.substr(0, 4).c_str())-1900;
st.tm_mon = atoi(strTime.substr(5, 2).c_str());
st.tm_mday = atoi(strTime.substr(8, 2).c_str());
st.tm_hour = a...
What's the difference between Task.Start/Wait and Async/Await?
...ed queues up a series of windows messages, each one of which does a little bit of work? Now what happens? You return control to the message loop, it starts pulling messages out of the queue, doing a little bit of work each time, and the last job that's done is "execute the continuation of the task...
Style input element to fill remaining width of its container
...
flex for the win (again); very relevant answer in 2019
– secretwep
Mar 27 '19 at 19:44
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Tools for JPEG optimization? [closed]
...hey recompress the image at reducing quality factors perhaps with a little bit of filtering and they use some quality metric to decide when to stop.
– koan
May 4 '17 at 12:07
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How can I run MongoDB as a Windows service?
...ngod.lock file. This still appears to be an issue with 1.8.1 running on 64-bit.
– SethO
Apr 25 '11 at 15:04
4
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Why is transposing a matrix of 512x512 much slower than transposing a matrix of 513x513?
...e size of 64 bytes. Each line can hold 8 of the elements in the matrix (64-bit int).
The critical stride would be 2048 bytes, which correspond to 4 rows of the matrix (which is continuous in memory).
Assume we're processing row 28. We're attempting to take the elements of this row and swap them ...