X1e  X2e  X3e  X4e
360    0    0    0
360    0    0    0
260    0    0    0
0      0    0    0
0      0    0    0
0      0    0    0
90     0    0    0
360    0  360    0
360    0  360  260

for (i in c(1,4)){
  e <- assign(paste("X",i, "e",sep = ""),i)
  dat <- dat[with(dat, !((e>0)&(e<270))), ]
}