Re: table: problem with nan and if

[Nick Dokos]

Uwe Brauer <oub@mat.ucm.es> writes:

>> Uwe Brauer <oub@mat.ucm.es> writes:
>
>
>> I'm not very familiar with calc, but am wondering if the issue is the
>> 'nan'. In many languages, a nan is a 'polluting' variable i.e. once you
>> have a nan as a form anywhere in your calculation, the result will
>> always be a nan. Many languages actually have a special function to test
>> for a nan because it isn't actually a 'value'. Don't know if this is the
>> case with calc. 
>
> Yeah, when I googled, I found complains about nan using in calc but I
> did not really found an working alternative.
>
>> Perhaps an alternative strategy might help. Could you address what is
>> generating the nan and change that so that it generates something else,
>> possibly even a blank string and avoid the nan altogether? 
>
> I tried nil and other expressions but non really worked, so maybe a calc
> guru could clarify?
>

Could you write the formulas in lisp instead? You might be able to control
things more easily:

  (info "(org) Formula syntax for Lisp")

-- 
Nick

"There are only two hard problems in computer science: cache
invalidation, naming things, and off-by-one errors." -Martin Fowler