[R] Turning a logical vector into its indices without losing its length
I have the code below which gives me what I want for temp based on
logvec but I was wondering if there was a shorter way ( i.e :
a one liner ) without having to initialize temp to zeros. This is
purely for learning purposes. Thanks.
logvec - c(TRUE,FALSE,FALSE,TRUE,FALSE,FALSE,TRUE,FALSE)
temp-numeric(length(invec))
temp[invec]-which(invec)
temp
[1] 1 0 0 4 0 0 7 0
obviously, the code below doesn't work.
temp - which(invec)
temp
[1] 1 4 7
This is not an offer (or solicitation of an offer) to buy/se...{{dropped}}
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and provide commented, minimal, self-contained, reproducible code.
Re: [R] Turning a logical vector into its indices without losing its length
On Fri, 24 Aug 2007, Leeds, Mark (IED) wrote:
I have the code below which gives me what I want for temp based on
logvec but I was wondering if there was a shorter way ( i.e :
a one liner ) without having to initialize temp to zeros. This is
purely for learning purposes. Thanks.
logvec - c(TRUE,FALSE,FALSE,TRUE,FALSE,FALSE,TRUE,FALSE)
R logvec[logvec] - which(logvec)
R logvec
[1] 1 0 0 4 0 0 7 0
hth,
Z
temp-numeric(length(invec))
temp[invec]-which(invec)
temp
[1] 1 0 0 4 0 0 7 0
obviously, the code below doesn't work.
temp - which(invec)
temp
[1] 1 4 7
This is not an offer (or solicitation of an offer) to buy/se...{{dropped}}
__
R-help@stat.math.ethz.ch mailing list
https://stat.ethz.ch/mailman/listinfo/r-help
PLEASE do read the posting guide http://www.R-project.org/posting-guide.html
and provide commented, minimal, self-contained, reproducible code.
__
R-help@stat.math.ethz.ch mailing list
https://stat.ethz.ch/mailman/listinfo/r-help
PLEASE do read the posting guide http://www.R-project.org/posting-guide.html
and provide commented, minimal, self-contained, reproducible code.
Re: [R] Turning a logical vector into its indices without losing its length
On 8/24/07, Gabor Grothendieck [EMAIL PROTECTED] wrote:
Here are two solutions:
logvec - c(TRUE,FALSE,FALSE,TRUE,FALSE,FALSE,TRUE,FALSE)
ifelse(logvec, seq_along(logvec), 0)
[1] 1 0 0 4 0 0 7 0
replace(logvec * 0, logvec, which(logvec))
[1] 1 0 0 4 0 0 7 0
Actually the * 0 is not needed. The last one could simply be:
replace(logvec, logvec, which(logvec))
On 8/24/07, Leeds, Mark (IED) [EMAIL PROTECTED] wrote:
I have the code below which gives me what I want for temp based on
logvec but I was wondering if there was a shorter way ( i.e :
a one liner ) without having to initialize temp to zeros. This is
purely for learning purposes. Thanks.
logvec - c(TRUE,FALSE,FALSE,TRUE,FALSE,FALSE,TRUE,FALSE)
temp-numeric(length(invec))
temp[invec]-which(invec)
temp
[1] 1 0 0 4 0 0 7 0
obviously, the code below doesn't work.
temp - which(invec)
temp
[1] 1 4 7
This is not an offer (or solicitation of an offer) to buy/se...{{dropped}}
__
R-help@stat.math.ethz.ch mailing list
https://stat.ethz.ch/mailman/listinfo/r-help
PLEASE do read the posting guide http://www.R-project.org/posting-guide.html
and provide commented, minimal, self-contained, reproducible code.
__
R-help@stat.math.ethz.ch mailing list
https://stat.ethz.ch/mailman/listinfo/r-help
PLEASE do read the posting guide http://www.R-project.org/posting-guide.html
and provide commented, minimal, self-contained, reproducible code.
Re: [R] Turning a logical vector into its indices without losing its length
Here are two solutions:
logvec - c(TRUE,FALSE,FALSE,TRUE,FALSE,FALSE,TRUE,FALSE)
ifelse(logvec, seq_along(logvec), 0)
[1] 1 0 0 4 0 0 7 0
replace(logvec * 0, logvec, which(logvec))
[1] 1 0 0 4 0 0 7 0
On 8/24/07, Leeds, Mark (IED) [EMAIL PROTECTED] wrote:
I have the code below which gives me what I want for temp based on
logvec but I was wondering if there was a shorter way ( i.e :
a one liner ) without having to initialize temp to zeros. This is
purely for learning purposes. Thanks.
logvec - c(TRUE,FALSE,FALSE,TRUE,FALSE,FALSE,TRUE,FALSE)
temp-numeric(length(invec))
temp[invec]-which(invec)
temp
[1] 1 0 0 4 0 0 7 0
obviously, the code below doesn't work.
temp - which(invec)
temp
[1] 1 4 7
This is not an offer (or solicitation of an offer) to buy/se...{{dropped}}
__
R-help@stat.math.ethz.ch mailing list
https://stat.ethz.ch/mailman/listinfo/r-help
PLEASE do read the posting guide http://www.R-project.org/posting-guide.html
and provide commented, minimal, self-contained, reproducible code.
__
R-help@stat.math.ethz.ch mailing list
https://stat.ethz.ch/mailman/listinfo/r-help
PLEASE do read the posting guide http://www.R-project.org/posting-guide.html
and provide commented, minimal, self-contained, reproducible code.
Re: [R] Turning a logical vector into its indices without losing its length
[Leeds, Mark (IED)] I have the code below which gives me what I want for temp based on invec but I was wondering if there was a shorter way ( i.e : a one liner ) without having to initialize temp to zeros. This is ppurely for learning purposes. Thanks. invec - c(TRUE,FALSE,FALSE,TRUE,FALSE,FALSE,TRUE,FALSE) temp-numeric(length(invec)) temp[invec]-which(invec) temp [1] 1 0 0 4 0 0 7 0 A mere: invec * seq_along(invec) would do it. To be honest, I dislike the multiplication trickery, and so prefer Gabor's solution, even if a bit longer: ifelse(invec, seq_along(invec), 0) -- François Pinard http://pinard.progiciels-bpi.ca __ R-help@stat.math.ethz.ch mailing list https://stat.ethz.ch/mailman/listinfo/r-help PLEASE do read the posting guide http://www.R-project.org/posting-guide.html and provide commented, minimal, self-contained, reproducible code.
Re: [R] Turning a logical vector into its indices without losing its length
On 8/24/07, Gabor Grothendieck [EMAIL PROTECTED] wrote: On 8/24/07, Gabor Grothendieck [EMAIL PROTECTED] wrote: Here are two solutions: logvec - c(TRUE,FALSE,FALSE,TRUE,FALSE,FALSE,TRUE,FALSE) ifelse(logvec, seq_along(logvec), 0) [1] 1 0 0 4 0 0 7 0 replace(logvec * 0, logvec, which(logvec)) [1] 1 0 0 4 0 0 7 0 Actually the * 0 is not needed. The last one could simply be: replace(logvec, logvec, which(logvec)) If logvec can have NAs then this solution would not work but could be modified to be done like this: replace(logvec, which(logvec), which(logvec)) __ R-help@stat.math.ethz.ch mailing list https://stat.ethz.ch/mailman/listinfo/r-help PLEASE do read the posting guide http://www.R-project.org/posting-guide.html and provide commented, minimal, self-contained, reproducible code.
