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rlistmultiple-columnsxtsmultiplication

Multiplying element in list with columns in another list in the same period

I have these 2 lists. 

library(tidyquant)

standin1<-cbind(c("AAPL","JPM"),c("MSFT","FB"))
wantedstocks<-unique(c(standin1))
eeee<-tq_get(wantedstocks,"stock.prices", from = "2015-01-01", to = "2015-01-27")
prices_tbl1<-split(eeee,eeee$symbol)
prices_tbl2<-lapply(prices_tbl1,function(x) xts(x$adjusted,x$date))
prices_tbl3<-do.call(merge,prices_tbl2) #combine xts objects
split_prices_into_years<-split.xts(prices_tbl3,f="weeks",k=1)
jjj<-split_prices_into_years[2:4]
tt<-lapply(jjj, function(x) x[1,])

jjj
[[1]]
              FB      JPM     MSFT      AAPL
2015-01-05 77.19 55.15255 42.39050  99.43689
2015-01-06 76.15 53.72248 41.76831  99.44625
2015-01-07 76.15 53.80447 42.29900 100.84071
2015-01-08 78.18 55.00679 43.54335 104.71526
2015-01-09 77.74 54.05040 43.17737 104.82755

[[2]]
              FB      JPM     MSFT      AAPL
2015-01-12 76.72 53.58586 42.63753 102.24452
2015-01-13 76.45 53.59496 42.41794 103.15231
2015-01-14 76.28 51.74593 42.05195 102.75926
2015-01-15 74.05 50.08816 41.61278  99.97034
2015-01-16 75.18 50.94437 42.30815  99.19356

[[3]]
              FB      JPM     MSFT     AAPL
2015-01-20 76.24 50.74397 42.44539 101.7485
2015-01-21 76.74 50.90794 42.01535 102.5253
2015-01-22 77.65 52.45639 43.12246 105.1925
2015-01-23 77.83 51.62751 43.16822 105.7353

> tt
[[1]]
              FB      JPM    MSFT     AAPL
2015-01-05 77.19 55.15255 42.3905 99.43689

[[2]]
              FB      JPM     MSFT     AAPL
2015-01-12 76.72 53.58586 42.63753 102.2445

[[3]]
              FB      JPM     MSFT     AAPL
2015-01-20 76.24 50.74397 42.44539 101.7485

I want to multiply each column in the jjj list with the respective element in the tt list. So that 

             FB                    
2015-01-05 77.19               2015-01-05 5958.296 
2015-01-06 76.15      FB       2015-01-06 5878.019
2015-01-07 76.15 (X)  77.19 =  2015-01-07 5878.019             
2015-01-08 78.18               2015-01-08 6034.714
2015-01-09 77.74               2015-01-09 6000.751


          FB                    
2015-01-12 76.72               2015-01-12 5958.296 
2015-01-13 76.45      FB       2015-01-13 5865.244
2015-01-14 76.28  (X) 76.72  = 2015-01-14 5852.202             
2015-01-15 74.05               2015-01-15 5681.116
2015-01-16 75.18               2015-01-16 5767.81

and so on. So i want the output to be on the same form as jjj just with the elements from tt multiplied on like showed above. Any help is really appreciated.

Solution

  • Not terribly pretty, but gets the job done with a loop:

    result_list <- list(length=length(jjj))
for(i in 1:length(jjj)) {
    result_list[[i]] <- as.matrix(jjj[[i]]) * matrix(rep(tt[[i]], nrow(jjj[[i]])), ncol=ncol(tt[[i]]), byrow=T)
}

    or with sapply, but not any prettier:

    sapply(1:length(jjj), function(i) as.matrix(jjj[[i]]) * matrix(rep(tt[[i]], nrow(jjj[[i]])), ncol=ncol(tt[[i]]), byrow=T))