matthiasm@8: function b = isposdef(a)
matthiasm@8: % ISPOSDEF   Test for positive definite matrix.
matthiasm@8: %    ISPOSDEF(A) returns 1 if A is positive definite, 0 otherwise.
matthiasm@8: %    Using chol is much more efficient than computing eigenvectors.
matthiasm@8: 
matthiasm@8: %  From Tom Minka's lightspeed toolbox
matthiasm@8: 
matthiasm@8: [R,p] = chol(a);
matthiasm@8: b = (p == 0);