Couple of quick questions...inf and reading data

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two little questions...
is output of inf division because data small display or out of range of doubles? work others (using same calculation) save inf.

and how can read file , sd card line line...the line read selected variable.
the variable @ start of each line in recorded data ie line 1. 2. 3. 4. etc if help.

quote
is output of inf division because data small display or out of range of doubles?

inf means infinity, not small.inf result of doing dumb, dividing 0.

quote
and how can read file , sd card line line...the line read selected variable.

you can't. there nothing defines "line". there characters/byte. convention, of bytes funny things print heads , paper feed mechanisms , cursor positions.

you can read , store data in array until 1 of funny bytes found ('\n' or '\r'). can count number of times 1 of funny characters has along, see if have right "line".

now, if have fixed length records, story lot different. in case, there no reason read whole file, can seek() start of nth record.


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