See my following example:
In[347]:= x=Tuples[{0,1},3]
Select[x,! #[[1]]==#[[2]]==#[[3]]&]
Select[x,DuplicateFreeQ]
Out[347]= {{0, 0, 0}, {0, 0, 1}, {0, 1, 0}, {0, 1, 1}, {1, 0, 0}, {1,
0, 1}, {1, 1, 0}, {1, 1, 1}}
Out[348]= {{0, 0, 1}, {0, 1, 0}, {0, 1, 1}, {1, 0, 0}, {1, 0, 1}, {1,
1, 0}}
Out[349]= {}
I want to obtain the similar result as the second command by using the DuplicateFreeQ in the last command shown above. Why doesn't my usage return any results?
Regards,
Zhao