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Summarizing multiple columns with dplyr? [duplicate]
...df %>% group_by(grp) %>% summarise_all(list(mean))
#> # A tibble: 3 x 5
#> grp a b c d
#> <int> <dbl> <dbl> <dbl> <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...
What is a Portable Class Library?
...E Oct 9 2017: Article comparing/constrasting .NET Core/Std/PCL
UPDATE Nov 23 2016: Article by Rick Strahl
UPDATE Oct 29 2016: .NETStandard 1->2 FAQ
UPDATE Oct 19 2016: This is the best interview/video I've seen to date covering .NET Standard 2.0
UPDATE Sep 27 2016: .NET Standard 2.0 announcemen...
C++虚继承的概念 - C/C++ - 清泛网 - 专注C/C++及内核技术
...--------------------------
2: //名称：blog_virtual_inherit.cpp
3: //说明：C++虚拟继承学习演示
4: //环境：VS2005
5: //blog：pppboy.blog.163.com
6: //----------------------------------------------------
7: #include "stdafx.h"
8: #include <iostream>
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Is a statically-typed full Lisp variant possible?
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Eli BarzilayEli Barzilay
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Why is C so fast, and why aren't other languages as fast or faster? [closed]
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34 Answers
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Use ffmpeg to add text subtitles [closed]
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edited Jun 23 at 19:08
answered Jul 11 '13 at 2:53
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What is the difference between active and passive FTP?
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edited Apr 19 '18 at 6:38
answered Nov 9 '09 at 4:57
pax...
What would cause an algorithm to have O(log log n) complexity?
...are root of the size at each layer?
For example, let's take the number 65,536. How many times do we have to divide this by 2 until we get down to 1? If we do this, we get
65,536 / 2 = 32,768
32,768 / 2 = 16,384
16,384 / 2 = 8,192
8,192 / 2 = 4,096
4,096 / 2 = 2,048
2,048 / 2 = 1,024
1,024 / 2 = 5...
What are the differences between 'call-template' and 'apply-templates' in XSL?
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Johnny Bones
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answered Dec 18 '10 at 13:02
TomalakTomalak
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Declaring abstract method in TypeScript
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The name property is marked as protected. This was added in TypeScript 1.3 and is now firmly est...