向矩阵添加随机数MATLAB

Question

I want to generate 100x1 matrix with 3 numbers -1,1 and 0. I want to be able to control how much of 1's and -1's are assigned. I tried using

 Y = rand(10,1)<0.1 

but this only gives me 0's an 1's. But I am able to control the number of 1's in the matrix . Is there a similar type of function that I can use for adding and controlling the number of -1 and 1's along with the default 0. Sorry I am new matlab env.

Thanks

Answer 1

Start by initializing your array:

x = [-1*ones(30,1); zeros(25,1);ones(45,1)];

then use matlab's wonderful indexing with randperm :

y= x(randperm(100));
plot (y, 'o')