It would help if you told us what software you're using - the reference to nominal code probably means Sage, but that isn't guaranteed.
Since you are a new poster, you should also provide a bit of background information about yourself - what sort of qualifications and experience you have in this field, that sort of thing, in order for people to get some idea how to gauge answers to any questions you post so that they're at the right level.
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Vince M Hudd - Soft Rock Software
(I only came here looking for fellow apiarists...)