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Relative frequencies / proportions with dplyr
...()) %>%
mutate(freq = n / sum(n))
# am gear n freq
# 1 0 3 15 0.7894737
# 2 0 4 4 0.2105263
# 3 1 4 8 0.6153846
# 4 1 5 5 0.3846154
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MC Emperor
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answered Dec 16 '10 at 2:55
CristianCristian
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53
Someone connected to the database. Try to switch to another database and then, to drop it:
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edited Jan 30 '16 at 20:51
answered Jun 28 '11 at 14:20
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edited Apr 3 '18 at 6:04
Shylendra Madda
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Rails DB Migration - How To Drop a Table?
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edited Jan 5 '16 at 17:23
Joe Kennedy
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answered...
App Inventor 2 浮点数与字节转换教程 · App Inventor 2 中文网
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概述
IEEE 754浮点数格式
单精度（32位/4字节）
转换示例
方案一：通过WebView用JavaScript转换（推荐）
HTML页面
App Inventor积木块
方案二：纯积木块实现（近似）
方案三：通过...
How do I replace a git submodule with another repo?
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123
If the location (URL) of the submodule has changed, then you can simply:
Modify your .gitmodul...