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Re:Zmij: Faster floating point double-to-string conversion by nhatcher on Friday December 19, 2025 @06:37AM (#46324684)
Quick question, if you are still around :).

I have been doing some tests. Is it correct to assume that it converts 1.0 to "0.000000000000001e+15".

Is there a test suite it is passing?

Re:Zmij: Faster floating point double-to-string conversion by vitaut on Friday December 19, 2025 @09:34AM (#46326286)
It converts 1.0 to "1.e-01" which reminds me to remove the trailing decimal point =). dtoa-benchmark tests that the algorithm produces valid results on its dataset.
Re:Zmij: Faster floating point double-to-string conversion by nhatcher on Friday December 19, 2025 @10:54AM (#46327184)
So if I use:

    #include "zmij.h"
    #include <stdio.h>

    int main() {
        char buf[zmij::buffer_size];
        zmij::dtoa(1.0, buf);
        puts(buf);
    }
I get `g++ zmij.cc test.c -o test && ./test` => `0.000000000000001e+15`
Re:Zmij: Faster floating point double-to-string conversion by vitaut on Friday December 19, 2025 @07:16PM (#46332528)
My bad, you are right. The small integer optimization should be switched to a different output method (or disabled since it doesn't provide much value). Thanks for catching this!
Re:Zmij: Faster floating point double-to-string conversion by vitaut on Friday December 19, 2025 @07:23PM (#46332572)
Should be fixed now.
Re:Zmij: Faster floating point double-to-string conversion by dtolnay on Friday December 19, 2025 @12:54PM (#46328766)
"1.e-01" is for 0.1, not 1.0.
Re:Zmij: Faster floating point double-to-string conversion by nhatcher on Friday December 19, 2025 @01:41PM (#46329316)
I assume they meant 1.e+00

That is what Schubfach does

Re:Zmij: Faster floating point double-to-string conversion by vitaut on Friday December 19, 2025 @07:25PM (#46332583)
Yeah, that's what I meant.