Divide all element of a vector (with 9 elements) by first, second, ...hundredth element from another vector (with 100 elements)

Question

Hello I really need help with my program in R. I have vector with nine elements and I need divide each element by first, second, ...., hundredth, element from another vector. I try this for loop but it didn't works

er=matrix(1,100)
LCZ2016=matrix(1,100)

for(i in 2:100)
  for(j in 1:9)
  {
    {
      er[i]=rnorm(1, 0, SdeLcCZ2016)
      LCZ2016[i]=DEA['L'][CZ2016,][j,]/exp(er[i])
    } 
  }

the =DEA['L'][CZ2016,] is vector with 9 elements and I need create LCZ2016 with 100 elements like this

LCZ2016[1]=DEA['L'][CZ2016,][1] //exp(er[1])
LCZ2016[2]=DEA['L'][CZ2016,][2] //exp(er[2])
.
.
.
LCZ2016[50]=DEA['L'][CZ2016,][1] //exp(er[50])

etc. Please do you have any idea ?

This should be possible. But please provide a _minimal_ [reproducible example](https://stackoverflow.com/questions/5963269/how-to-make-a-great-r-reproducible-example). — markus, Dec 09 '18 at 11:45

YOLO · Accepted Answer · 2018-12-09T14:27:40.093

1

I think you can do:

a <- 1:9
b <- 1:100 

output = sapply(a, function(x) x/b)
print(dim(output))

[1] 100   9

Also, you can do as suggested by @Andre

sapply(a, /, b)

edited Dec 09 '18 at 14:27

answered Dec 09 '18 at 11:45

YOLO

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did you mean `sapply(a, `/`, b)` ? – Andre Elrico Dec 09 '18 at 13:31

score 1 · Answer 2 · answered Dec 09 '18 at 12:03

1

This is exactly what outer is meant for.

a <- 1:9
b <- 1:100 
out2 <- outer(a, b, '/')
dim(out2)
#[1]   9 100

Compare with YOLO's answer.

output <- sapply(a, function(x) x/b)

identical(t(out2), output)
#[1] TRUE

answered Dec 09 '18 at 12:03

Rui Barradas

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@markus Not deliberate, I've messed up the mouse clicks. – Rui Barradas Dec 09 '18 at 12:05

Divide all element of a vector (with 9 elements) by first, second, ...hundredth element from another vector (with 100 elements)

2 Answers2