test_dsrwon.R
In dst: Using the Theory of Belief Functions

# Tests "dsrwon" function
context("Compute unnormalized Dempster's Rule")
library(dst)
test_that("dsrwon", {
  # 
  # T1 x and y must be of class bcaspec. 
  # 
  x1 <- list(a=1:3, b="foo")
  y1 <- bca(tt = matrix(c(1,0,0,1,1,1),nrow=2, byrow = TRUE), m=c(0.6, 0.4),  cnames = c("a", "b", "c"),  varnames = "y1", idvar = 1)
  expect_error(dsrwon(x = x1, y = y1) , "One or more inputs not of class bcaspec.")
  #
  # T2 ncol of x and y must be equal. 
  # 
  x2 <- bca(tt = matrix(c(0,1,1,1,1,1,0,1,1,1,1,1),nrow=3, byrow = TRUE), m=c(0.2,0.5, 0.3), cnames =c("a", "b", "c","d"),  varnames = "x2", idvar = 1)
  expect_error(dsrwon(x = x2, y = y1) , "Nb of elements of frame x and frame y not equal.")
  #
  # T3 Value names of the frames must identical and in the same order.
  # 
  z1 <- bca(tt = matrix(c(1,0,0,1,1,1), ncol=2, byrow=TRUE), m= c(0.99, 0.01, 0), cnames =c("M", "T"), varnames = "Diagnosis1", idvar = 1)
  z2 <- bca(tt = matrix(c(1,0, 0,1, 1,1), ncol=2, byrow=TRUE), m= c(0.01, 0.99, 0), cnames =c("C", "T"), varnames = "Diagnosis2", idvar = 2)
  expect_error(dsrwon(x = z1, y = z2) , "Value names of the two frames differ. Check value names of variables as well as their position.")
  #
  # T4 warning message when evidence is completely contradictory
  # 
  cnames <- c("yes","no")
  f1<- t(matrix(c(1,0,1,1),ncol=2))
  m1<- c(1,0)
  x1 <- bca(f1, m1, cnames)
  f2<- t(matrix(c(0,1,1,1),ncol=2))
  m2<- c(1,0)
  x2 <- bca(f2, m2, cnames)
  expect_warning(dsrwon(x = x1, y = x2) , 'Totally conflicting evidence \\(con = 1\\). Data is inconsistent.')
})