Optimization,input variables with n set of values

I am trying with gamult optimization for multichannel luminaire. there are three optimizing variables(x1,x2,x3). But i need to start the optimization with n set of variables and get n-set of x1,x2,x3 as result(for multichannels). The below code uses n=1(single channel).

function y= sampleopt(x)

sigma=x(2)/2.35482;

spd=zeros(401,2);

X=zeros(401,1);

for lambda=380:780

spd(lambda-379, 1)=lambda;

spd(lambda-379, 2)=x(3)*((exp(-0.5*((lambda-x(1))/sigma^2))/(sigma*sqrt(2*pi)))); % spd of one channel

X(lambda-379,1)=lambda;

end