I'm using summary to get stats for a number list:
read.csv('nums.txt', header = F)
summary(x)
nums.txt:
value
1
2
3
How do i summarize this data by group/category using summary function?
nums.txt
category,value
A,1
A,2
A,3
B,4
B,5
B,6
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Sathish
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3What have you tried? What have you searched for? This question has been answered many times on SO. – Dason Mar 27 '13 at 13:11
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The answer is in your question: `by()` – Rcoster Mar 27 '13 at 13:12
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Also look for `tapply` here on SO. – Arun Mar 27 '13 at 13:13
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I'm new to R and i'm trying to extend this command line oneliner to use group by: http://stackoverflow.com/a/9826464/51402 – Sathish Mar 27 '13 at 13:16
1 Answers
1
If I google "r summary by" the first answer that comes up for me is a link to http://www.statmethods.net/stats/descriptives.html Which has a solution to your problem.
Another solution not mentioned there is as follows
library(data.table)
x <- data.table(x)
x[, summary(Value), by=list(Group1, Group2)] # assuming more than one group. Otherwise, just use by=Group1
Ricardo Saporta
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