floating point - how to perform high precision calculations in D? -

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for universitary work have approximate numbers - euler 1 series. therefore have add small numbers, have problems precision. if number ist small doesn't influence result.

real s;  //sum of previous terms ulong k; //factorial  s += 1.0/ k;

after each step, k gets smaller, after 10th round result isn't changeing anymore , stuck @ 2.71828

if need solution run using native types should able reasonable results trying add numbers of similar magnitude. 1 way compute first x terms of series, , repeatedly replace 2 smallest numbers there sum:

auto data = real[n]; foreach(i, ref v; data) {   v = fn(i); }  while(data.length > 1) {   data.sort(); // iirc .sort deprecated forget replaced it.   data[1] += data[0];   data = data[1..$]; }  return data[0];

(a min heap make bit faster.)


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