# high precision, calculate correction value

hi @all,

a question: '5 minutes' represented as a fraction of a day (represented by '1') are an 'odd' 'uneven' - 'endless fraction' value, already in decimals, and also in doubles (can be calculated as '=time(0;5;0),

thus there is a gap between the value calc can deal with ('=1/24/60*5' or '=1/24/12', or '=1/288', all resulting in '0,00347222222222222') and the ideal precise value of 0,003472222222222222222222222222222... , something like 0,000000000000000002222222222222222... or - as calc has one digit more hidden from users view: 0,000000000000000000222222222222222....

i can! calculate that gap quite precise to 1.9274705288631189921192130137104208E-19 with the 128 bit variant of 'weitz' (www.weitz.de/ieee), doe's anybody have an idea how i can get that value in a calc sheet? wouldn't need 35 digit precision, 15 or 16 digits acc. normal double is sufficient, just 10 digit could be enough.

i know the value cannot be added to the 5 minute value as it's beyond it's ULP, but if one can get such correction values i see some nice possibilities to do correct calculations.

let's say: 1/288 is a fraction which we know, exact, we can check that calc calculates with something like '0,0034722222222222220294, how to calculate the difference 'in the sheet'?

(sorry, i am! somewhat overworked, normally i should know such things by myself ... let me change the question ... what is the best - most elegant - way do get such values ?)