# Import Accuracy/General Accuracy

r[i] = SetPrecision[
Import[epath, {"Data", epath2, 9 + counts + 5*i - 2, excelfile2}],
prec];


epath is file name, epath2 is tab, count is row, excelfile2 is column. In the excel the cell holds the equation =.769/39.37. According to excel it .0195326390652781000000000. However in mathematica the result comes back as

r[1] = 0.01953263906527813106861480


Where is the extra 13106861480 coming from?

Whats more is if you put the equation into mathematica as .769/39.37 the result you get is 0.01953263906527813453806175 which has 3453806175. Where are these differences coming from? How come they don't change, I though it was computer noise but it's not changing. Can someone help?

• What is prec? – Rohit Namjoshi Oct 17 '20 at 19:09
• precision of argument set, 200 – Rookey Oct 17 '20 at 19:18
• When SetPrecision is used to raise the precision of a number, it augments with binary (as opposed to decimal) zeros. In[163]:= n1 = .769/39.37; n2 = SetPrecision[n1, 30] Out[164]= 0.0195326390652781345380617494811 In[165]:= RealDigits[n2, 2] Out[165]= {{1, 0, 1, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 1, 0, 1, 1, 1, 0, 1, 0, 0, 1, 1, 0, 1, 1, 1, 1, 1, 1, 1, 0, 1, 0, 1, 1, 0, 1, 1, 0, 0, 1, 1, 0, 1, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0}, -5} – Daniel Lichtblau Oct 18 '20 at 15:12
• I don't understand? it just generates extra numbers? How are they not random then? and which one is accurate/correct? – Rookey Oct 18 '20 at 15:32