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Determine the data types of a data frame's columns
...o use ?str(). To explore some examples, let's make some data:
set.seed(3221) # this makes the example exactly reproducible
my.data <- data.frame(y=rnorm(5),
x1=c(1:5),
x2=c(TRUE, TRUE, FALSE, FALSE, FALSE),
X3=letters[1:5])
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Split a vector into chunks in R
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326
A one-liner splitting d into chunks of size 20:
split(d, ceiling(seq_along(d)/20))
More det...
Applying a function to every row of a table using dplyr?
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edited Aug 6 '19 at 3:20
answered Jul 14 '14 at 0:20
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Maximum number of characters using keystrokes A, Ctrl+A, Ctrl+C and Ctrl+V
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43
There's a dynamic programming solution. We start off knowing 0 keys can make us 0 A's. Then we i...
CGRidCtrl控件 学习心得 - C/C++ - 清泛网 - 专注C/C++及内核技术
...介绍... 1
2.1 功能介绍... 1
2.2 框架介绍... 2
2.3 主要类介绍... 4
2.3.1 CGridCtrl类... 4
2.3.2 CGridCellCheck类... 5
2.3.3 CGridCellCombo类... 7
2.4 控件类CGridCtrl常用函数说明... 10
2.4.1 行和列的设置... 10
2.4.2 ...
What are the differences between json and simplejson Python modules?
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13 Answers
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“ValueError: zero length field name in format” error in Python 3.0,3.1,3.2
I'm trying learn Python (3 to be more specific) and I'm getting this error:
3 Answers
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Calculate difference in keys contained in two Python dictionaries
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234
You can use set operations on the keys:
diff = set(dictb.keys()) - set(dicta.keys())
Here is...
Can dplyr package be used for conditional mutating?
... 1 & b == 4), 2,
ifelse(a == 0 | a == 1 | a == 4 | a == 3 | c == 4, 3, NA)))
Added - if_else: Note that in dplyr 0.5 there is an if_else function defined so an alternative would be to replace ifelse with if_else; however, note that since if_else is stricter than ifelse (both leg...
How to slice an array in Bash
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317
See the Parameter Expansion section in the Bash man page. A[@] returns the contents of the arr...