R/lpath_is_gradation.R

In kst: Knowledge Space Theory

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### lpath_is_gradation.R
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### dependencies: library(sets)
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### 2009-04-20: created
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lpath_is_gradation <- function(x) {

   ### check for gradation
   FUN <- function(y) {
      sd <- diff(unlist(lapply(y, function(z) length(z))), lag=1)
      all(sd <= 1)
   }
   lapply(x, FUN)

}