Alfredo_MF - 10 months ago 47

R Question

Having the following matrix and vector.

`x<-matrix(c(1,4,7,`

2,5,8,

3,6,9), nrow = 3)

w <- c(1,1,1)

res <- c()

What is the

`res[1]<-w %*%x[1,]`

res[2]<-w %*%x[2,]

res[3]<-w %*%x[3,]

res[4]<-w %*%x[1,]

res[5]<-w %*%x[2,]

sum(res)>1000 #Multiply recursiverly till the sum of the results sum(res) goes further than 1000.

Answer Source

Here is how to do it **recursively**:

```
f <- function(x, w, res){
if (sum(res)>1000)
return(res)
res <- c(res, x%*%w)
f(x,w,res)
}
```

Call it with your pre-defined objects. That is:

```
f(x, w, res)
```

Which will give you:

```
# [1] 6 15 24 6 15 24 6 15 24 6 15 24 6 15 24 6 15 24 6 15 24 6 15 24 6 15 24 6 15 24 6 15 24 6 15 24 6 15 24 6 15 24 6 15 24 6 15 24 6 15 24 6 15 24 6 15 24 6 15 24 6
# [62] 15 24 6 15 24 6 15 24
```