[Solved] Selecting column sequences and creating variables

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We could split the dataset (‘df’) with ‘1416’ columns to equal size ‘118’ columns by creating a grouping index with gl 

 lst <- setNames(lapply(split(1:ncol(df), as.numeric(gl(ncol(df), 118,
            ncol(df)))), function(i) df[,i]), paste0('site', 1:12))

Or you can create the ‘lst’ without using the split

 lst <- setNames(lapply(seq(1, ncol(df), by = 118), 
            function(i) df[i:(i+117)]), paste0('site', 1:12))

If we need to create 12 dataset objects in the global environment, list2env is an option (I would prefer to work within the ‘lst’ itself) 

 list2env(lst, envir=.GlobalEnv)

Using a small dataset (‘df1’) with ‘8’ columns

  lst1 <- setNames(lapply(split(1:ncol(df1), as.numeric(gl(ncol(df1), 
         2, ncol(df1)))), function(i) df1[,i]), paste0('site', 1:4))
  list2env(lst1, envir=.GlobalEnv)

  head(site1,3)
  #  V1 V2
  #1  6 12
  #2  4  7
  #3 14 14

 head(site4,3)
 #  V7 V8
 #1 10  2
 #2  5  4
 #3  5  0

data

set.seed(24)
df1 <- as.data.frame(matrix(sample(0:20, 8*10, replace=TRUE), ncol=8))

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solved Selecting column sequences and creating variables