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Group by multiple columns in dplyr, using string vector input
...ike so:
data = data.frame(
asihckhdoydkhxiydfgfTgdsx = sample(LETTERS[1:3], 100, replace=TRUE),
a30mvxigxkghc5cdsvxvyv0ja = sample(LETTERS[1:3], 100, replace=TRUE),
value = rnorm(100)
)
# get the columns we want to average within
columns = names(data)[-3]
library(dplyr)
df1 <- data...
How can I determine the direction of a jQuery scroll event?
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edited Mar 21 '13 at 17:50
user372743
answered Dec 1 '10 at 17:04
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How to split a long regular expression into multiple lines in JavaScript?
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Append integer to beginning of list in Python [duplicate]
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How to activate JMX on my JVM for access with jconsole?
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How to base64 encode image in linux bash / shell
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155
You need to use cat to get the contents of the file named 'DSC_0251.JPG', rather than the file...
How does the const constructor actually work?
...ningful sorting order.
This means that const expressions like const Foo(1, 1) can represent any usable form that is useful for comparison in virtual machine.
The VM only needs to take into account the value type and arguments in the order in which they occur in this const expression. And, of cou...
Creating dataframe from a dictionary where entries have different lengths
Say I have a dictionary with 10 key-value pairs. Each entry holds a numpy array. However, the length of the array is not the same for all of them.
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Format number to 2 decimal places
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edited Oct 22 '18 at 9:57
Madhur Bhaiya
25.4k1010 gold badges3737 silver badges5151 bronze badges
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