# [R] (no subject)

Dimitri Liakhovitski dimitri.liakhovitski at gmail.com
Tue Jan 5 23:15:08 CET 2016

```Jean and Dennis, thank you so much for your solutions!
They are super-fast, thanks a lot!
Happy new year!
Dimitri

On Thu, Dec 24, 2015 at 2:50 PM, Adams, Jean <jvadams at usgs.gov> wrote:
> Excellent job providing example data and a desired result.
>
> This code works on the example you provided.  Hope it helps.
>
> Jean
>
> # reshape the info data frame
> library(tidyr)
> info2 <- gather(myinfo, set, val, -game)
> info2\$set <- as.numeric(gsub("[[:alpha:]]", "", info2\$set))
>
> # add a new column to the x data frame
> y <- t(x[,grep("char", names(x))])
> newx <- x
> newx\$char <- row(y)[y==1]
>
> # merge and define winner
> res <- merge(newx, info2)
> res\$winner <- with(res, ifelse(char==val, 1, 0))
> res
>
>
> On Wed, Dec 23, 2015 at 3:35 PM, Dimitri Liakhovitski
> <dimitri.liakhovitski at gmail.com> wrote:
>>
>> Merry upcoming Christmas - for those of us who celebrate it!
>>
>> # I have data frame x.
>> x <- data.frame(game = c(rep(1, 4), rep(2, 4)), set = rep(c(1,1,2,2),
>> 2), player = rep(1:2, 4),
>>                 char1 = c(1,0,0,0,0,0,0,1), char2 =
>> c(0,0,1,0,0,1,0,0), char3 = c(0,1,0,1,0,0,0,0),
>>                 char4 = c(0,0,0,0,1,0,1,0))
>> x
>> # There are several games (2 here). Each game has several sets (2
>> here. In each set participate
>> # several players (2 here).
>> # Each player possesses 1 or 4 possible characteristics.
>> # For example, in game 1, set 1, player 1 has characteristic 1 and player
>> 2 -
>> # characteristic 3
>>
>> # I also have data frame myinfo:
>> (myinfo <- data.frame(game = 1:2, set1 = c(3, 4), set2 = c(2, 1)))
>> # It tells me:
>> # in game 1, set 1 the winner was the player with characteristic 3
>> # in game 1, set 2 the winner was the player with characteristic 2, etc.
>>
>> # I need to merge the 2 to produce the result below.
>> # I just need an additional column that - for each game and each set -
>> # has a 1 in the row of the player who had the winning characteristic
>> # (as per myinfo) and has a 0 otherwise.
>>
>> result <- x
>> result\$winner <- c(0, 1, 1, 0, 1, 0, 0, 1)
>> result
>>
>> # I have written a long loop that loops through each set of each game,
>> identifies
>> # which characteristic wins in myinfo, and puts a 1 against the winning
>> row.
>> # But it's taking forever. Could it be done faster? Thanks a lot!
>>
>> # Important: In my real game the number of players could be more than
>> 2 and so can
>> # the number of games and the number of sets per game.
>> # However, we can assume that the number of sets per game is always the
>> same,
>> # and the number of players per set is always the same.
>>
>>
>> --
>> Dimitri Liakhovitski
>>
>> ______________________________________________
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>> and provide commented, minimal, self-contained, reproducible code.
>
>

--
Dimitri Liakhovitski

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