大约有 48,000 项符合查询结果(耗时:0.0401秒) [XML]

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eval command in Bash and its typical uses

After reading the bash man pages and with respect to this post . 10 Answers 10 ...
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Dynamically select data frame columns using $ and a character value

I have a vector of different column names and I want to be able to loop over each of them to extract that column from a data.frame. For example, consider the data set mtcars and some variable names stored in a character vector cols . When I try to select a variable from mtcars using a dynamic s...
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What is the difference between “long”, “long long”, “long int”, and “long long int” in C++?

I am transitioning from Java to C++ and have some questions about the long data type. In Java, to hold an integer greater than 2 32 , you would simply write long x; . However, in C++, it seems that long is both a data type and a modifier. ...
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How to check BLAS/LAPACK linkage in NumPy and SciPy?

I am builing my numpy/scipy environment based on blas and lapack more or less based on this walk through. 5 Answers ...
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Difference between >>> and >>

What is the difference between >>> and >> operators in Java? 7 Answers ...
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SLF4J: Failed to load class “org.slf4j.impl.StaticLoggerBinder”

My application is to be deployed on both tcServer and WebSphere 6.1. This application uses ehCache and so requires slf4j as a dependency. As a result I've added the slf4j-api.jar (1.6) jar to my war file bundle. ...
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How to remove a key from Hash and get the remaining hash in Ruby/Rails?

... your five-minutes-of-editing are up, you can always copy, delete, modify, and repost a comment. – iconoclast May 13 at 23:17 add a comment  |  ...
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Given a number, find the next higher number which has the exact same set of digits as the original n

I just bombed an interview and made pretty much zero progress on my interview question. Can anyone let me know how to do this? I tried searching online but couldn't find anything: ...
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Reorder levels of a factor without changing order of values

I have data frame with some numerical variables and some categorical factor variables. The order of levels for those factors is not the way I want them to be. ...
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How is this fibonacci-function memoized?

...mechanism in Haskell is by-need: when a value is needed, it is calculated, and kept ready in case it is asked for again. If we define some list, xs=[0..] and later ask for its 100th element, xs!!99, the 100th slot in the list gets "fleshed out", holding the number 99 now, ready for next access. Th...