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I'm stuck on a seemingly simple problem. I'm trying to subset the data by several numbers and it cuts out half of the rows. Here is the sample code:
test2 < as.matrix(c(1,1,1,1,3,3,7,7,7,7))
Count < tapply(test2[,1], test2[,1], length) # count for each value
spp < unique(test2[,1])
Count1 < as.data.frame(cbind(Count,spp))
Max < max(Count)
Count1$sppMax < ifelse(Count1$Count >= Max, Count1$spp, 0) # only keep values that =Max
Count2 < subset(Count1, sppMax > 0) #get rid of values that are less than Max
AllMax < unique(Count2$sppMax)
test3 < subset(test2, test2[,1] == AllMax)
this works where there is only one value for AllMax, how to make it work when there are multiple?


I see that this is your input: c(1,1,1,1,3,3,7,7,7,7)
what do you want the output to be?
what could the multiple values of AllMax be?
Yasir Kaheil


I want the output to be 1,1,1,1,7,7,7,7
The multiple values of AllMax are 1 and 7.
I think I've figured it out though, I added a loop at the end:
test < as.matrix(c(1,1,1,1,3,3,7,7,7,7))
Count < tapply(test[,1], test[,1], length) # count for each value
spp < unique(test[,1])
Count1 < as.data.frame(cbind(spp,Count))
Max < max(Count1$Count)
Count1$sppMax < ifelse(Count1$Count >= Max, Count1$spp, 0) # only keep values that =Max
Count2 < subset(Count1, sppMax > 0) #get rid of values that are less than Max
AllMax < unique(Count2$sppMax)
test2 < test[0,] # set up the blank header, same format as test2
for(i in 1:length(AllMax)) { # run 1 round of the loop for each value in the vector AllMax
tempset < subset(test, test[,1] == AllMax[i]) #subset all the values in test2 column 1 that match the current value in the AllMax
test2 < rbind(test2,tempset) # bind the subset with the blank header (first round of the loop) or with subsets from previous values of AllMax (subsequent rounds)
}


Hi. Maybe this:
ct < table(test)
as.numeric(names(ct[ct==max(ct)]))
test[test[,1]%in%as.numeric(names(ct[ct==max(ct)])),,drop=FALSE]
?
Andrija
On Wed, Jul 11, 2012 at 8:33 PM, Amanduh320 < [hidden email]> wrote:
> I'm stuck on a seemingly simple problem. I'm trying to subset the data by
> several numbers and it cuts out half of the rows. Here is the sample code:
>
> test < as.matrix(c(1,1,1,1,3,3,7,7,7,7))
> Count < tapply(test[,1], test[,1], length) # count for each value
> spp < unique(test[,1])
> Count1 < as.data.frame(cbind(Count,spp))
> Max < max(Count)
> Count1$sppMax < ifelse(Count1$Count >= Max, Count1$spp, 0) # only keep
> values that =Max
> Count2 < subset(Count1, sppMax > 0) #get rid of values that are less
> than Max
> AllMax < unique(Count2$sppMax)
> test2 < subset(test, test[,1] == AllMax)
>
>
> this works where there is only one value for AllMax, how to make it work
> when there are multiple?
>
> Thank you!
>
> 
> View this message in context:
> http://r.789695.n4.nabble.com/Subsetbasedonmultiplevaluestp4636159.html> Sent from the R help mailing list archive at Nabble.com.
>
> ______________________________________________
> [hidden email] mailing list
> https://stat.ethz.ch/mailman/listinfo/rhelp> PLEASE do read the posting guide
> http://www.Rproject.org/postingguide.html> and provide commented, minimal, selfcontained, reproducible code.
>
[[alternative HTML version deleted]]
______________________________________________
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https://stat.ethz.ch/mailman/listinfo/rhelpPLEASE do read the posting guide http://www.Rproject.org/postingguide.htmland provide commented, minimal, selfcontained, reproducible code.


yes just use %in% instead of == AllMax.. but also use table for count
Yasir Kaheil


Hi,
Try this: (a variant of andrija)
testct<table(test)
subset(test,!is.na(match(test,as.integer(names(testct[testct%in%max(testct)])))))
[,1]
[1,] 1
[2,] 1
[3,] 1
[4,] 1
[5,] 7
[6,] 7
[7,] 7
[8,] 7
A.K.
 Original Message 
From: Amanduh320 < [hidden email]>
To: [hidden email]
Cc:
Sent: Wednesday, July 11, 2012 2:33 PM
Subject: [R] Subset based on multiple values
I'm stuck on a seemingly simple problem. I'm trying to subset the data by
several numbers and it cuts out half of the rows. Here is the sample code:
test < as.matrix(c(1,1,1,1,3,3,7,7,7,7))
Count < tapply(test[,1], test[,1], length) # count for each value
spp < unique(test[,1])
Count1 < as.data.frame(cbind(Count,spp))
Max < max(Count)
Count1$sppMax < ifelse(Count1$Count >= Max, Count1$spp, 0) # only keep
values that =Max
Count2 < subset(Count1, sppMax > 0) #get rid of values that are less
than Max
AllMax < unique(Count2$sppMax)
test2 < subset(test, test[,1] == AllMax)
this works where there is only one value for AllMax, how to make it work
when there are multiple?
Thank you!

View this message in context: http://r.789695.n4.nabble.com/Subsetbasedonmultiplevaluestp4636159.htmlSent from the R help mailing list archive at Nabble.com.
______________________________________________
[hidden email] mailing list
https://stat.ethz.ch/mailman/listinfo/rhelpPLEASE do read the posting guide http://www.Rproject.org/postingguide.htmland provide commented, minimal, selfcontained, reproducible code.
______________________________________________
[hidden email] mailing list
https://stat.ethz.ch/mailman/listinfo/rhelpPLEASE do read the posting guide http://www.Rproject.org/postingguide.htmland provide commented, minimal, selfcontained, reproducible code.

