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Group by multiple columns in dplyr, using string vector input
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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 %>%...
What characters are valid for JavaScript variable names?
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1000
+50
To quot...
PHP: Count a stdClass object
...urn the right number when I run the count($obj) function. The object has 30 properties, but the return on the count() function is say 1.
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Replacing column values in a pandas DataFrame
... something like this:
w['female'] = w['female'].map({'female': 1, 'male': 0})
(Here I convert the values to numbers instead of strings containing numbers. You can convert them to "1" and "0", if you really want, but I'm not sure why you'd want that.)
The reason your code doesn't work is because...
How to create a cron job using Bash automatically without the interactive editor?
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20 Answers
20
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Generating random numbers in Objective-C
...a head mainly, and I want a way to generate a pseudo-random number between 0 and 74. In Java I would use the method:
13 Ans...
Mercurial move changes to a new branch
...e extension. Suppose you have a history like this:
@ changeset: 2:81b92083cb1d
| tag: tip
| summary: my new feature: edit file a
|
o changeset: 1:8bdc4508ac7b
| summary: my new feature: add file b
|
o changeset: 0:d554afd54164
summary: initial
This means, revisi...
How to create circle with Bézier curves?
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10 Answers
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Why does the C# compiler go mad on this nested LINQ query?
...machine) and very long time to compile (actually I get IO exception after 10 minutes).
1 Answer
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Create list of single item repeated N times
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809
You can also write:
[e] * n
You should note that if e is for example an empty list you get a...