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rrangemax

maximum value from values between two zeros

I have values in a column and would like to pick the maximum value from non-zero ranges in that column. A range is defined by non-zero values between two zeros. I am not sure if this explanation is right though. Kindly see the example below. I have done this is excel but I need to be able to do this in R and I am not sure of how to go about it. Any guide on where to start will be appreciated. My target is the column named "out".

ind<-c(0,0,0,0.4,0.6,0.7,0.7,0.9,0,0,0,1,3,10,0,0)
out<-c(0,0,0,0.9,0.9,0.9,0.9,0.9,0,0,0,10,10,10,0,0)
bbb<-data.frame (ind,out)
Solution

  • Here is a way to do it iteratively. Probably slow for big datasets.

    m=c(0,0,0,0.1,0.6,0.3,0,0,0.2,0.1,0.2,0,0,0)
maxims=0
aux=NULL
pos=1
for (i in 1:length(m)){

  if (m[i]!=0){
    aux=c(aux,m[i])
  }
  if (m[i]==0 && length(aux)>0){
    maxims[pos]=max(aux)
    aux=NULL
    pos=pos+1
  }
}
> maxims
[1] 0.6 0.2