[R] Sum of vector elements
Hi, Is it possible to avoid using do and while loops to calculate the sum of the elements of a vector until the appearance of the first positive element. -- View this message in context: http://r.789695.n4.nabble.com/Sum-of-vector-elements-tp4639395.html Sent from the R help mailing list archive at Nabble.com. __ R-help@r-project.org 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] Sum of vector elements
I'd do something like this: x - sample(seq(-10, 10)) sum(x[seq_len(which.max(x 0)]) Though others might have more direct solutions. which.max() gets you the index of the first time x 0 -- seq_len gives you numbers 1 to that index -- then just subset and sum like normal. Best, Michael On Tue, Aug 7, 2012 at 7:37 AM, number10 havana_dr...@ymail.com wrote: Hi, Is it possible to avoid using do and while loops to calculate the sum of the elements of a vector until the appearance of the first positive element. -- View this message in context: http://r.789695.n4.nabble.com/Sum-of-vector-elements-tp4639395.html Sent from the R help mailing list archive at Nabble.com. __ R-help@r-project.org 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@r-project.org 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] Sum of vector elements
Another approach... not exactly more direct, but perhaps more robust and more general: tmp - aggregate(x,list(lvl=cumsum(abs(diff(c(FALSE,x0), FUN=sum) ans - tmp[0==tmp$lvl,x] abs(diff()) finds transitions, FALSE forces level zero to represent negative numbers cumsum marks levels (groups of positive and not-positive numbers) aggregate does the summation ans may be empty if x started with positive numbers. --- Jeff NewmillerThe . . Go Live... DCN:jdnew...@dcn.davis.ca.usBasics: ##.#. ##.#. Live Go... Live: OO#.. Dead: OO#.. Playing Research Engineer (Solar/BatteriesO.O#. #.O#. with /Software/Embedded Controllers) .OO#. .OO#. rocks...1k --- Sent from my phone. Please excuse my brevity. R. Michael Weylandt michael.weyla...@gmail.com wrote: I'd do something like this: x - sample(seq(-10, 10)) sum(x[seq_len(which.max(x 0)]) Though others might have more direct solutions. which.max() gets you the index of the first time x 0 -- seq_len gives you numbers 1 to that index -- then just subset and sum like normal. Best, Michael On Tue, Aug 7, 2012 at 7:37 AM, number10 havana_dr...@ymail.com wrote: Hi, Is it possible to avoid using do and while loops to calculate the sum of the elements of a vector until the appearance of the first positive element. -- View this message in context: http://r.789695.n4.nabble.com/Sum-of-vector-elements-tp4639395.html Sent from the R help mailing list archive at Nabble.com. __ R-help@r-project.org 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@r-project.org 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@r-project.org 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] Sum of vector elements
I'll add my suggestion, which first extracts from x the elements
up to but not including the first positive one and then sums them:
f3 - function(x) { sum(x[cumsum(x0) == 0]) }
Michaels suggestion was
sum(x[seq_len(which.max(x 0)])
but that includes the first positive element so I think it should be
at least
f1 - function(x) sum(x[seq_len(which.max(x0)-1)])
(but that still fails in some cases).
Jeff's was
f2 - function (x) {
tmp - aggregate(x, list(lvl = cumsum(abs(diff(c(FALSE, x 0), FUN =
sum)
tmp[0 == tmp$lvl, x]
}
To test them, make a list of datasets
xs - list(allNeg=c(-1, -3, -9), allPos=c(1,3,9), firstPos=c(1,-3,-9),
firstNeg=c(-1,-3,+9), misc=c(-1,-3,9,-27,-81))
sapply(xs, function(x)try(f1(x)))
allNeg allPos firstPos firstNeg misc
000 -4 -4
sapply(xs, function(x)try(f2(x)))
$allNeg
[1] -13
$allPos
numeric(0)
$firstPos
numeric(0)
$firstNeg
[1] -4
$misc
[1] -4
sapply(xs, function(x)try(f3(x)))
allNeg allPos firstPos firstNeg misc
-1300 -4 -4
Bill Dunlap
Spotfire, TIBCO Software
wdunlap tibco.com
-Original Message-
From: r-help-boun...@r-project.org [mailto:r-help-boun...@r-project.org] On
Behalf
Of Jeff Newmiller
Sent: Tuesday, August 07, 2012 10:25 AM
To: R. Michael Weylandt; number10
Cc: r-help@r-project.org
Subject: Re: [R] Sum of vector elements
Another approach... not exactly more direct, but perhaps more robust and more
general:
tmp - aggregate(x,list(lvl=cumsum(abs(diff(c(FALSE,x0), FUN=sum)
ans - tmp[0==tmp$lvl,x]
abs(diff()) finds transitions, FALSE forces level zero to represent negative
numbers
cumsum marks levels (groups of positive and not-positive numbers)
aggregate does the summation
ans may be empty if x started with positive numbers.
---
Jeff NewmillerThe . . Go Live...
DCN:jdnew...@dcn.davis.ca.usBasics: ##.#. ##.#. Live Go...
Live: OO#.. Dead: OO#.. Playing
Research Engineer (Solar/BatteriesO.O#. #.O#. with
/Software/Embedded Controllers) .OO#. .OO#. rocks...1k
---
Sent from my phone. Please excuse my brevity.
R. Michael Weylandt michael.weyla...@gmail.com wrote:
I'd do something like this:
x - sample(seq(-10, 10))
sum(x[seq_len(which.max(x 0)])
Though others might have more direct solutions.
which.max() gets you the index of the first time x 0 -- seq_len
gives you numbers 1 to that index -- then just subset and sum like
normal.
Best,
Michael
On Tue, Aug 7, 2012 at 7:37 AM, number10 havana_dr...@ymail.com
wrote:
Hi, Is it possible to avoid using do and while loops to calculate the
sum of
the elements of a vector until the appearance of the first positive
element.
--
View this message in context:
http://r.789695.n4.nabble.com/Sum-of-vector-elements-tp4639395.html
Sent from the R help mailing list archive at Nabble.com.
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__
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PLEASE do read the posting guide http://www.R-project.org/posting-guide.html
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__
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PLEASE do read the posting guide http://www.R-project.org/posting-guide.html
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Re: [R] sum in vector
rowsum(value, paste(factor1, factor2, factor3)) That is dangerous in general, and always inefficient. Imagine factor1 is c(a, a b) and factor2 is (b c, c). Use interaction with drop = T. Hadley -- Assistant Professor / Dobelman Family Junior Chair Department of Statistics / Rice University http://had.co.nz/ __ R-help@r-project.org 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] sum in vector
hy guys i have one question :) i have two vectors markets and price market - c(1, 5, 7, 9, 9, 6, 5, 4, 4, 3, 1, 2, 1) price - c(100, 20, 30, 10, 50, 23, 23, 33, 96, 6, 4, 38, 96) i would like sum prices: market 1: (100+4+96), market 2: (38),..., market 9: (10+50) ao i would like get this result: (200, 38, ..., 60) and i don't wanna use while, for loops... is there any other function to sum these :) tnx for helping ;) -- View this message in context: http://r.789695.n4.nabble.com/sum-in-vector-tp3041661p3041661.html Sent from the R help mailing list archive at Nabble.com. __ R-help@r-project.org 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] sum in vector
tapply(price, market, sum) andydol...@gmail.com On 14 November 2010 13:02, lgpeco pavic.o...@gmail.com wrote: hy guys i have one question :) i have two vectors markets and price market - c(1, 5, 7, 9, 9, 6, 5, 4, 4, 3, 1, 2, 1) price - c(100, 20, 30, 10, 50, 23, 23, 33, 96, 6, 4, 38, 96) i would like sum prices: market 1: (100+4+96), market 2: (38),..., market 9: (10+50) ao i would like get this result: (200, 38, ..., 60) and i don't wanna use while, for loops... is there any other function to sum these :) tnx for helping ;) -- View this message in context: http://r.789695.n4.nabble.com/sum-in-vector-tp3041661p3041661.html Sent from the R help mailing list archive at Nabble.com. __ R-help@r-project.org 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@r-project.org 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] sum in vector
Am 14.11.2010 13:02, schrieb lgpeco: hy guys i have one question :) i have two vectors markets and price market- c(1, 5, 7, 9, 9, 6, 5, 4, 4, 3, 1, 2, 1) price- c(100, 20, 30, 10, 50, 23, 23, 33, 96, 6, 4, 38, 96) i would like sum prices: market 1: (100+4+96), market 2: (38),..., market 9: (10+50) ao i would like get this result: (200, 38, ..., 60) and i don't wanna use while, for loops... is there any other function to sum these :) tnx for helping ;) you could cbind() the vectors and use sum( result[row1==i] ) for market number i, I guess? -- Alexx __ R-help@r-project.org 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] sum in vector
Have a look at the reshape2 package. http://had.co.nz/reshape/ reshape2 is, to the user a slight modification of rehape but the author says it is much faster. The code below seems to do what you want. - xx - data.frame(market, price) library(reshape2) yy - melt(xx, id=1) dcast(yy, market ~ variable, sum) - --- On Sun, 11/14/10, lgpeco pavic.o...@gmail.com wrote: From: lgpeco pavic.o...@gmail.com Subject: [R] sum in vector To: r-help@r-project.org Received: Sunday, November 14, 2010, 7:02 AM hy guys i have one question :) i have two vectors markets and price market - c(1, 5, 7, 9, 9, 6, 5, 4, 4, 3, 1, 2, 1) price - c(100, 20, 30, 10, 50, 23, 23, 33, 96, 6, 4, 38, 96) i would like sum prices: market 1: (100+4+96), market 2: (38),..., market 9: (10+50) ao i would like get this result: (200, 38, ..., 60) and i don't wanna use while, for loops... is there any other function to sum these :) tnx for helping ;) -- View this message in context: http://r.789695.n4.nabble.com/sum-in-vector-tp3041661p3041661.html Sent from the R help mailing list archive at Nabble.com. __ R-help@r-project.org 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@r-project.org 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] sum in vector
Try this: rowsum(price, market) On Sun, Nov 14, 2010 at 10:02 AM, lgpeco pavic.o...@gmail.com wrote: hy guys i have one question :) i have two vectors markets and price market - c(1, 5, 7, 9, 9, 6, 5, 4, 4, 3, 1, 2, 1) price - c(100, 20, 30, 10, 50, 23, 23, 33, 96, 6, 4, 38, 96) i would like sum prices: market 1: (100+4+96), market 2: (38),..., market 9: (10+50) ao i would like get this result: (200, 38, ..., 60) and i don't wanna use while, for loops... is there any other function to sum these :) tnx for helping ;) -- View this message in context: http://r.789695.n4.nabble.com/sum-in-vector-tp3041661p3041661.html Sent from the R help mailing list archive at Nabble.com. __ R-help@r-project.org 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. -- Henrique Dallazuanna Curitiba-Paraná-Brasil 25° 25' 40 S 49° 16' 22 O [[alternative HTML version deleted]] __ R-help@r-project.org 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] sum in vector
to be more general you can also use aggregate: aggregate(price,list(market),sum) Henrique Dallazuanna wrote: Try this: rowsum(price, market) On Sun, Nov 14, 2010 at 10:02 AM, lgpeco pavic.o...@gmail.com wrote: hy guys i have one question :) i have two vectors markets and price market - c(1, 5, 7, 9, 9, 6, 5, 4, 4, 3, 1, 2, 1) price - c(100, 20, 30, 10, 50, 23, 23, 33, 96, 6, 4, 38, 96) i would like sum prices: market 1: (100+4+96), market 2: (38),..., market 9: (10+50) ao i would like get this result: (200, 38, ..., 60) and i don't wanna use while, for loops... is there any other function to sum these :) tnx for helping ;) -- View this message in context: http://r.789695.n4.nabble.com/sum-in-vector-tp3041661p3041661.html Sent from the R help mailing list archive at Nabble.com. __ R-help@r-project.org 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. -- Henrique Dallazuanna Curitiba-Paraná-Brasil 25° 25' 40 S 49° 16' 22 O [[alternative HTML version deleted]] __ R-help@r-project.org 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. -- View this message in context: http://r.789695.n4.nabble.com/sum-in-vector-tp3041661p3041991.html Sent from the R help mailing list archive at Nabble.com. __ R-help@r-project.org 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] sum in vector
Hi all, On Sun, Nov 14, 2010 at 10:06 PM, Henrique Dallazuanna www...@gmail.com wrote: Try this: rowsum(price, market) does it work with multiple factors/groups ? using multiple factors such as c(factor1,factor2,factor3,...) as second arg with rowsum() doesnt seem to work! am i missing something ? regards KM __ R-help@r-project.org 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] sum in vector
thx all for help this function works fine aggregate(price,list(market),sum) i also find another one sapply(x, function) -- View this message in context: http://r.789695.n4.nabble.com/sum-in-vector-tp3041661p3042089.html Sent from the R help mailing list archive at Nabble.com. __ R-help@r-project.org 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] sum in vector
Try this: rowsum(value, paste(factor1, factor2, factor3)) On Sun, Nov 14, 2010 at 5:21 PM, km srikrishnamo...@gmail.com wrote: Hi all, On Sun, Nov 14, 2010 at 10:06 PM, Henrique Dallazuanna www...@gmail.com wrote: Try this: rowsum(price, market) does it work with multiple factors/groups ? using multiple factors such as c(factor1,factor2,factor3,...) as second arg with rowsum() doesnt seem to work! am i missing something ? regards KM __ R-help@r-project.org 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. -- Henrique Dallazuanna Curitiba-Paraná-Brasil 25° 25' 40 S 49° 16' 22 O [[alternative HTML version deleted]] __ R-help@r-project.org 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.
