generate random number between positive and negative and sum of this number is zero

I want generate random number between positive and negative, and then the sum of this number equal to zero. what have I should do?

Answer 1

[Bruno Luong]

You probably need this:

https://www.mathworks.com/matlabcentral/fileexchange/9700-random-vectors-with-fixed-sum

[kukuh widarsono]

great sir...thanks you very much. I think, it suits with my problem

Answer 2

[Voss]

x = randn(); % random number from standard Normal distribution
y = -x;      % another number such that the sum of x and y is 0

x

x = -0.4716

y

y = 0.4716

x+y

ans = 0

[kukuh widarsono]

thanks. but I want make array/matrix in my program...not just one time or one number.

[Voss]

x = randn(5); % 5x5 random matrix from standard Normal distribution
y = -x;       % another matrix such that the sum of x and y is 0
x

x = 5×5

-1.3777 -0.9362 -1.0312 -2.0870 0.9580 0.1070 1.1208 -0.8803 -0.0622 0.7201 1.1074 0.3074 0.7390 -0.3496 0.2003 -1.2134 0.5940 -0.3744 0.3251 0.3406 0.5072 0.3389 -1.6013 1.9403 0.2310

y

y = 5×5

1.3777 0.9362 1.0312 2.0870 -0.9580 -0.1070 -1.1208 0.8803 0.0622 -0.7201 -1.1074 -0.3074 -0.7390 0.3496 -0.2003 1.2134 -0.5940 0.3744 -0.3251 -0.3406 -0.5072 -0.3389 1.6013 -1.9403 -0.2310

x+y

ans = 5×5

0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0