You need #include <limits>. Other than that, I don't know. I code on Windows, not Mac, but the code looks right.
WARNING: min() != -infinity. For doubles, min is the smallest number greater than 0. -infinity == -max() John -----Original Message----- From: sqlite-users-boun...@sqlite.org [mailto:sqlite-users-boun...@sqlite.org] On Behalf Of Michael Chen Sent: Monday, October 19, 2009 4:59 PM To: General Discussion of SQLite Database Subject: Re: [sqlite] Infinity //Dear there, it seems that I cannot insert std::numeric_limits<double>::max(). I am on Mac Osx 10.5 //anybody can take a look at the code? I am new to sqlite3. comments on coding also welcome. #include <string> #include <iostream> #include <cassert> #include <sqlite3.h> using namespace std; int main(){ double infinity = std::numeric_limits<double>::max(); double ninfinity = std::numeric_limits<double>::min(); sqlite3 *db; char *zErrMsg = 0; int rc; rc = sqlite3_open(":memory:", &db); if( rc ){ fprintf(stderr, "Can't open database: %s\n", sqlite3_errmsg(db)); sqlite3_close(db); exit(1); } sqlite3_stmt* create_tl; rc = sqlite3_prepare_v2(db, "create table tl (number real)", -1, &create_tl,NULL); printf("%i\n",rc); if ( rc != SQLITE_OK) exit(rc); rc = sqlite3_step(create_tl); if ( rc != SQLITE_DONE) exit(rc); sqlite3_stmt* insert_tl; rc = sqlite3_prepare_v2(db,"insert into tl values(:number)",-1, &insert_tl,NULL); if ( rc != SQLITE_OK) exit(rc); sqlite3_bind_double(insert_tl, 1, 1.1); rc = sqlite3_step(insert_tl); if (rc != SQLITE_DONE) exit(rc); sqlite3_bind_double(insert_tl, 1, infinity); //this line would fail, error code 21 rc = sqlite3_step(insert_tl); if (rc != SQLITE_DONE) exit(rc); sqlite3_bind_double(insert_tl, 1, ninfinity); rc = sqlite3_step(insert_tl); if (rc != SQLITE_DONE) exit(rc); sqlite3_bind_double(insert_tl, 1, 3.3); rc = sqlite3_step(insert_tl); if (rc != SQLITE_DONE) exit(rc); sqlite3_stmt* select_tl; rc = sqlite3_prepare_v2(db, "select * from tl",-1,&select_tl,NULL); if (rc != SQLITE_OK) exit(rc); while ( sqlite3_step(select_tl) == SQLITE_ROW){ printf("%e",sqlite3_column_double(select_tl,0)); printf("\n"); } if (rc != SQLITE_DONE) exit(rc); sqlite3_finalize(select_tl); sqlite3_close(db); printf("exit normally\n"); } On Sun, Oct 18, 2009 at 5:58 PM, John Crenshaw <johncrens...@priacta.com>wrote: > SQLite stores the data however you give it. I'm not aware of any > documentation requiring that 9e999 be considered infinity, nor any > requiring that the command line treat invalid numbers as null. Most > likely, treating NaN as null is simply a way for the command line to > behave reasonably in an otherwise undefined situation. > > Practically, 9e999 is beyond the "infinity" limit for doubles on > whatever compiler was used to build the command line. I think this limit > is technically arbitrary, so on some compilers, either now, or in the > future, 9e999 could very possibly NOT be infinity. > std::numeric_limits<double>::max() should be a standard (read "safe") > way of getting the "infinity" value in C++. > > In the Visual C++ 2005 compiler, the max double is > 1.7976931348623158e+308. I'm not sure that this is constant however, so > don't count on it. > > -----Original Message----- > From: sqlite-users-boun...@sqlite.org > [mailto:sqlite-users-boun...@sqlite.org] On Behalf Of Michael Chen > Sent: Sunday, October 18, 2009 4:19 PM > To: General Discussion of SQLite Database > Subject: Re: [sqlite] Infinity > > > I am looking for the answer too. anybody know it? > > On Sat, Oct 17, 2009 at 12:23 AM, Dan Bishop <danbisho...@gmail.com> > wrote: > > > I've noticed that I can use IEEE Infinity values in SQLite by writing > > any literal too big for a double. > > > > sqlite> CREATE TABLE foo (x REAL); > > sqlite> INSERT INTO foo VALUES (9e999); -- +Inf > > sqlite> INSERT INTO foo VALUES (-9e999); -- -Inf > > sqlite> INSERT INTO foo VALUES (9e999 / 9e999); -- NaN: gets converted > > to NULL > > sqlite> .null NULL > > sqlite> select * FROM foo; > > Inf > > -Inf > > NULL > > sqlite> SELECT * FROM foo WHERE ABS(x) = 9e999; > > Inf > > -Inf > > > > Is it true on all platforms that 9e999 = Infinity and CAST(9e999 AS > > TEXT) = 'Inf'? What's the preferred SQL syntax for infinity? > > _______________________________________________ > > sqlite-users mailing list > > sqlite-users@sqlite.org > > http://sqlite.org:8080/cgi-bin/mailman/listinfo/sqlite-users > > > > > > -- > Best regards, > Michael Chen > Google Voice Phone.: 847-448-0647 > _______________________________________________ > sqlite-users mailing list > sqlite-users@sqlite.org > http://sqlite.org:8080/cgi-bin/mailman/listinfo/sqlite-users > _______________________________________________ > sqlite-users mailing list > sqlite-users@sqlite.org > http://sqlite.org:8080/cgi-bin/mailman/listinfo/sqlite-users > -- Best regards, Michael Chen Google Voice Phone.: 847-448-0647 _______________________________________________ sqlite-users mailing list sqlite-users@sqlite.org http://sqlite.org:8080/cgi-bin/mailman/listinfo/sqlite-users _______________________________________________ sqlite-users mailing list sqlite-users@sqlite.org http://sqlite.org:8080/cgi-bin/mailman/listinfo/sqlite-users
