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In Unix, how do you remove everything in the current directory and below it?
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edited Dec 9 '11 at 15:34
Flimm
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answered...
Summarizing multiple columns with dplyr? [duplicate]
... <dbl>
#> 1 1 3.08 2.98 2.98 2.91
#> 2 2 3.03 3.04 2.97 2.87
#> 3 3 2.85 2.95 2.95 3.06
If you want to summarize only certain columns, use summarise_at or summarise_if functions.
Alternatively, the purrrlyr package provides the same functionality:
library(purr...
How can we access context of an application in Robolectric?
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14 Answers
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C语言面试那些事儿──一道指针与数组问题 - C/C++ - 清泛网 - 专注C/C++及内核技术
...先看如下代码：int main(int argc, char** argv){ int a[5] = {1,2,3,4,5}; int* ptr = (int*)(&a + 1); ...首先看如下代码：
int main(int argc, char** argv)
{
int a[5] = {1,2,3,4,5};
int* ptr = (int*)(&a + 1);
printf("%d,%d\n", *(a+1), *(ptr-1));
return 0;
}
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项目管理实践教程一、工欲善其事，必先利其器【Basic Tools】 - 项目管理 -...
...ols】今天，我们首先安装一些必须的软件，主要有下面的4个，其中软件1和2使用在服务器机上，软件3和4安装在客户端机上。另外，我们还有用到MSBui 今天，我们首先安装一些必须的软件，主要有下面的4个，其中软件1和2使用...
What is the difference between _tmain() and main() in C++?
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Salman von Abbas
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answered May 22 '09 at 0:09
jalfjalf
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Determine version of Entity Framework I am using?
...are two versions 1 and 2? And version 2 is referred to as Entity Framework 4.0?
10 Answers
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How to force LINQ Sum() to return 0 while source collection is empty
...imon Belanger
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How to handle back button in activity
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Saurabh PareekSaurabh Pareek
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How can I get nth element from a list?
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edited Mar 24 at 13:41
Community♦
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answered Mar 7 '11 at 7:59
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