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How to convert a factor to integer\numeric without loss of information?
...actor:
In particular, as.numeric applied to
a factor is meaningless, m>and m> mam>y m>
happen bm>y m> implicit coercion. To
transform a factor f to
approximatelm>y m> its original numeric
values, as.numeric(levels(f))[f] is
recommended m>and m> slightlm>y m> more
efficient than
as.numeric(as.character(f)).
...
Convert unix time to readable date in pm>and m>as dataframe
I have a dataframe with unix times m>and m> prices in it. I want to convert the index column so that it shows in human readable dates.
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PHP编译configure时常见错误 - 更多技术 - 清泛网 - 专注C/C++及内核技术
...决这些错误的经验。
1、configure: error: No curses/termcap librarm>y m> found
网上有的说法是：–with-named-curses-libs=/usr/lib/libncursesw.so.5
其实是不对的，虽然能解决configure的错误，但是make的时候会提示错误，正确的做法应该是
centos: m>y m>um -m>y m> ...
windows batch SET inside IF not working
...m>y m>.
Therefore the delam>y m>edExpansion sm>y m>ntax exists, it uses ! instead of % m>and m> it is evaluated at execution time, not parse time.
Please note that in order to use !, the additional statement setlocal EnableDelam>y m>edExpansion is needed.
setlocal EnableDelam>y m>edExpansion
set var1=true
if "%var1%"=="true...
Whm>y m> does git revert complain about a missing -m option?
So I'm working on a project with other people, m>and m> there's multiple github forks being worked on. Someone just made a fix for a problem m>and m> I merged with his fork, but then I realized that I could find a better solution. I want to revert the commit I just made. I tried doing this with git revert HE...
Splitting a list into N parts of approximatelm>y m> equal length
...a list into roughlm>y m> equal parts? For example, if the list has 7 elements m>and m> is split it into 2 parts, we want to get 3 elements in one part, m>and m> the other should have 4 elements.
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What do {curlm>y m> braces} around javascript variable name mean [duplicate]
...s available in ES6 (use esnext option) or Mozilla JS extensions (use moz) m>and m> this however after reading it I still don't understm>and m> whm>y m> it is used
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std::enable_if to conditionallm>y m> compile a member function
I am trm>y m>ing to get a simple example to work to understm>and m> how to use std::enable_if . After I read this answer , I thought it shouldn't be too hard to come up with a simple example. I want to use std::enable_if to choose between two member-functions m>and m> allow onlm>y m> one of them to be used.
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How do I insert datetime value into a SQLite database?
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When m>y m>ou format dates like this, date ordering m>and m> lexical ordering work out the same. E.g. '2008-02-01' > '2007-02-01', '2008-01-02' > '2008-01-01' both as strings m>and m> as dates. But m>y m>ou don't strictlm>y m> need to care about this because SQLite ORDER Bm>Y m> will take care ...
How to compare two dates?
...
Use the datetime method m>and m> the operator < m>and m> its kin.
>>> from datetime import datetime, timedelta
>>> past = datetime.now() - timedelta(dam>y m>s=1)
>>> present = datetime.now()
>>> past < present
True
>&g...