On 2/27/19, Jim Borden <jim.bor...@couchbase.com> wrote: > Hello, > > I’ve been tracking down an odd problem where some of our results from an > application defined SQLite function are coming back as infinity on some > platforms (notably 32-bit Android, and all Windows). I’ve narrowed it down > to the following: > > Given the example input "1.7976931348623153e+308" encoded as UTF-8, the > following lines of code have the following results (z is the const char* > variable holding the text): > > double value = strtod(z, NULL); // value holds 1.7976931348623153E+308 > sqlite3AtoF(z, &value, sqlite3Strlen30(z), SQLITE_UTF8); // value now hold > +Inf > > My theory as to why this varies by platform is because of the use of long > double during this calculation, which can vary in size. On the failing > platforms they are the same size as regular double. This results in a > rounding error of the "scale" portion of the calculation (via sqlite3Pow10) > which results in a false infinity. > > Would this be considered a bug, or is precision not guaranteed to the same > level as strtod because of other factors?
This is a case of the precision not guaranteed due to other factors. -- D. Richard Hipp d...@sqlite.org _______________________________________________ sqlite-users mailing list sqlite-users@mailinglists.sqlite.org http://mailinglists.sqlite.org/cgi-bin/mailman/listinfo/sqlite-users
