Error in code: I cant get past debugging this piece of code

[Arvindh_Somanathan]

x=c(1,2,3,4)
y=c(4,5,6,7)
example1<-function(x,y)
  #start functions in curly bracket
{
  #initialize the values to store squared values
  
  n<-length(x)
  x1<-0
  y1<-0
  z1<-0
  {#then start iterations
    for(i in 1:n)
      x1[i]<-x[i]^2
    y1[i]<-y[i]^2
    z1[i]<-(x[i]/y[i])^2
    #close with curly bracket}
    sumx1<-sum(x1)
    sumy1<-sum(y1)
    sumz1<-sum(z1)
    g<- sumx1/ sumy1
    h<- sumz1
    cat("The values are",g,"and",h,"\n")
  }
  example1(x,y)

[melih_guven]

many functions in r are vectorized, it means you don't need loops for iteration

x=c(1,2,3,4) 
y=c(4,5,6,7)

cat("The values are",  sum(x^2)/sum(y^2),"and",  sum((x/y)^2),"\n")
#The values are 0.2380952 and 0.7990306 

[Arvindh_Somanathan]

Ok that makes sense; but what if I want to write a program that includes the iterations?

Thanks for the solution. It is correct but I wanted to use the iterations commands to practice loops.

[melih_guven]

"Of course someone has to write loops. It doesn’t have to be you." @JennyBryan

for (i in x) {f} means for each element in x do the f
for (i in seq_along(x)) {f} means for each index of x do the f

in your case, I would create the following function

example<-function(x,y){
  
  sum_of_squares1<-0
  sum_of_squares2<-0
  sum_of_squaresof_ratio<-0
  
  for (i in x){
    sum_of_squares1<-sum_of_squares1+i^2
  }
  
  for (i in y){
    sum_of_squares2<-sum_of_squares2+i^2
  }
  
  if(length(x)!=length(y)) stop("vectors are not the same lentgh")
  
  for (i in seq_along(x)){
    sum_of_squaresof_ratio <- sum_of_squaresof_ratio+(x[i]/y[i])^2
  }
  
  cat("The values are",  sum_of_squares1/sum_of_squares2,"and",  sum_of_squaresof_ratio,"\n")  
  

[nirgrahamuk]

@Arvindh_Somanathan

 z1<-0
  {#then start iterations
    for(i in 1:n)
      x1[i]<-x[i]^2
    y1[i]<-y[i]^2
    z1[i]<-(x[i]/y[i])^2
    #close with curly bracket}

the curly bracket occurs after the for condition. and you ommitted the closing one, by commenting it out ...

 z1<-0
  #then start iterations
    for(i in 1:n) {
      x1[i]<-x[i]^2
    y1[i]<-y[i]^2
    z1[i]<-(x[i]/y[i])^2
}    #close with curly bracket

[Arvindh_Somanathan]

@Arvindh_Somanathan

x=c(1,2,3,4)
y=c(4,5,6,7)
example1<-function(x,y)
  #start functions in curly bracket
{
  #initialize the values to store squared values
  
  n<-length(x)
  x1<-0
  y1<-0
  z1<-0
  {#then start iterations
    for(i in 1:n)
      x1[i]<-x[i]^2
    y1[i]<-y[i]^2
    z1[i]<-(x[i]/y[i])^2
    #close with curly bracket}
    sumx1<-sum(x1)
    sumy1<-sum(y1)
    sumz1<-sum(z1)
    g<- sumx1/ sumy1
    h<- sumz1
    cat("The values are",g,"and",h,"\n")
  }
  example1(x,y)

thanks melih; the code misses a ' curly bracket' at the end. This code was a trial in my learning curve. Million miles to go!!!

[Arvindh_Somanathan]

Could you please tell me where I have made mistakes in my code, so that I can learn from them. As I try to execute my code, it throws up an error that the values are NA and NA.

[nirgrahamuk]

If you are asking it seems you didnt understand the words in my post to you.
So here is a full edit version of your code, with the corrections I suggested to you.

x=c(1,2,3,4)
y=c(4,5,6,7)
example1<-function(x,y)
  #start functions in curly bracket
{
  #initialize the values to store squared values
  
  n<-length(x)
  x1<-0
  y1<-0
  z1<-0
  #then start iterations
    for(i in 1:n)
    {
      x1[i]<-x[i]^2
    y1[i]<-y[i]^2
    z1[i]<-(x[i]/y[i])^2
    }
    #close with curly bracket
    sumx1<-sum(x1)
    sumy1<-sum(y1)
    sumz1<-sum(z1)
    g<- sumx1/ sumy1
    h<- sumz1
    cat("The values are",g,"and",h,"\n")
  }
  example1(x,y)

[Arvindh_Somanathan]

Thanks Nir, I made mistakes in running the for loop.