Could it be that your data is all zeros (or at least some of it)? That could generate this warning.

Best,

Vladimir

On 8 Jan 2011, at 05:53, 飞鸟 wrote:

Dear SPM users,
　　Each time when I start to do estimate step in the procedure of DCM for MEG, the matlab's command window will appear such warning :
Warning: Log of zero.
> In spm_nlsi_N at 220
In spm_dcm_erp at 198
In spm_api_erp>estimate_Callback at 1034
In spm_api_erp at 40'　

　　Then it starts to compute and seems have no problem any more.
　　I wonder if this warning may influence the result.Could you tell me where the problem lies in or how can I solve this problem?
　　Any suggestions will be appreciated! Thank you!

--

Haoran LI (MS)
Brain Imaging Lab,
Research Center for Learning Science,
Southeast University
2 Si Pai Lou , Nanjing, 210096, P.R.China