The number of decimal digits used to display GPS values is computed wrongly. The base-10 logarithm needs to be rounded up to get the correct number.
E.g., in an example I had n=297, d=5. Since log10(d)=0.69..., it's rounded to 0, i.e. the fraction is displayed with no decimals (59). Rounding up the logarithm to 1 will correctly display 1 decimal (59.4).