Error with directionality index

[pranithavangala]

Hi

Im able t o create directionality index files with the “DI_from_matrix.pl”. But when I try to run the HMM_call.m I get the below error, can you tell me what is going wrong ?

Error using chol
Matrix must be positive definite.

Error in gaussLogprob (line 52)
R = chol(Sigma);

Error in mixGaussInferLatent (line 17)
logPz(:, k) = logMix(k) + gaussLogprob(mu(:, k), Sigma(:, :, k), X);

Error in mixGaussFit>estep (line 53)
[weights, ll] = mixGaussInferLatent(model, data);

Error in emAlgo (line 60)
[ess, ll] = estep(model, data);

[dhkron]

The DI code makes several assumptions about the inputs. Are your inputs both symmetric and positive?