proc optmodel;
	set OBS;
	num x {OBS};
	read data sashelp.iris into OBS=[_N_] x=SepalWidth;
	num n = card(OBS);

	var Mu init 0;
	var Sigma >= 0 init 2;

	impvar C {i in OBS} = x[i] - Mu;
	max LogLikelihood = -n * log(Sigma) - n/2 * log(2*constant('PI')) - 1/2/Sigma**2 * sum {i in OBS} C[i]**2;
	solve;
	print Mu Sigma;
	print LogLikelihood;

	max LogLikelihood2 = sum {i in OBS} log(PDF('normal',x[i],Mu,Sigma));
	solve;
	print Mu Sigma;
	print LogLikelihood2;

	num optMu = (sum {i in OBS} x[i]) / n;
	num optSigma = sqrt(sum {i in OBS} (x[i] - optMu)**2 / n);
	print optMu optSigma;
quit;