R/s.R

In Calculator.LR.FNs: Calculator for LR Fuzzy Numbers

s <-
function(M, N)  {
options(warn = -1) 

if ( messages(M) != 1 )  { return( messages(M) ) }
if ( messages(N) != 1 )  { return( messages(N) ) }

if ( (M[4]==1 & N[4]==0) | (M[4]==0 & N[4]==1) | (M[4]==0.5 & N[4]==0.5) ) 
   {
    a1 = M[1]-N[1]
    a2 = M[2]+N[3]
    a3 = M[3]+N[2]
    a4 = M[4]
    print( noquote( paste0("the result of subtraction is  (core = ", a1, ", left spread = " , a2, ", right spread = " , a3, ")"
     ,  if ( a4 == 0 ) { paste0(" LR" ) }  else if ( a4 == 1 ) { paste0(" RL" ) }  else { paste0(" L" ) }  ) ) )
    return( invisible( c(a1,a2,a3,a4) ) )
   }
 else
  {
   return( noquote( paste0("Subtraction has NOT a closed form of a LR fuzzy number" ) ) )
  } 
}