Generating vectors of length N with only -1s and 1s.

I want to generate some M number of vectors of length N with the entries restricted to -1s and 1s and the vectors should not be repetitive. Is it possible to do so? If yes, how?

Answer 1

[Stephen23]

>> M = 5;
>> N = 19;
>> randi(0:1,M,N)*2-1
ans =
  -1   1  -1   1  -1  -1   1  -1   1  -1  -1   1  -1   1   1  -1  -1   1   1
   1  -1  -1  -1  -1   1  -1  -1   1  -1  -1   1  -1  -1   1   1   1  -1   1
  -1   1  -1   1   1   1   1  -1   1  -1  -1  -1   1  -1   1   1   1   1  -1
   1  -1  -1   1  -1   1  -1  -1  -1  -1  -1   1  -1   1  -1   1   1   1  -1
  -1  -1   1  -1  -1  -1   1   1   1   1   1  -1  -1   1   1   1   1   1   1

[Aditya Petety]

Does it return non repetetive vectors?