... this is a borderline case.

Because YOU haven't set the rounding mode:

#include <stdio.h>
#include <float.h>

int main( int argc, char **argv ) {
    double n;

    printf( "Setting mode CHOP; controlFP returned: %u\n", 
            _controlfp( _RC_CHOP, _MCW_RC ) 
         );
    for( n = 0.000005; n < 0.0001; n += 0.00001 ) {
        printf( "%.15f %.5f\n", n, n );
    }

    printf( "Setting mode UP; controlFP returned: %u\n", 
             _controlfp( _RC_UP, _MCW_RC ) 
         );
    for( n = 0.000005; n < 0.0001; n += 0.00001 ) {
        printf( "%.15f %.5f\n", n, n );
    }

    printf( "Setting mode DOWN; controlFP returned: %u\n", 
             _controlfp( _RC_DOWN, _MCW_RC ) 
         );
    for( n = 0.000005; n < 0.0001; n += 0.00001 ) {
        printf( "%.15f %.5f\n", n, n );
    }

    printf( "Setting mode NEAR; controlFP returned: %u\n", 
            _controlfp( _RC_NEAR, _MCW_RC ) 
         );
    for( n = 0.000005; n < 0.0001; n += 0.00001 ) {
        printf( "%.15f %.5f\n", n, n );
    }
    return 1;
}

[download]
C:\test>ieeeroundingmode.exe
Setting mode CHOP; controlFP returned: 525087
0.000005000000000 0.00001
0.000015000000000 0.00002
0.000025000000000 0.00003
0.000035000000000 0.00003
0.000045000000000 0.00004
0.000055000000000 0.00005
0.000065000000000 0.00006
0.000075000000000 0.00007
0.000085000000000 0.00008
0.000095000000000 0.00009
Setting mode UP; controlFP returned: 524831
0.000005000000000 0.00001
0.000015000000000 0.00002
0.000025000000000 0.00003
0.000035000000000 0.00004
0.000045000000000 0.00005
0.000055000000000 0.00006
0.000065000000000 0.00007
0.000075000000000 0.00008
0.000085000000000 0.00009
0.000095000000000 0.00010
Setting mode DOWN; controlFP returned: 524575
0.000005000000000 0.00001
0.000015000000000 0.00002
0.000025000000000 0.00003
0.000035000000000 0.00003
0.000045000000000 0.00004
0.000055000000000 0.00005
0.000065000000000 0.00006
0.000075000000000 0.00007
0.000085000000000 0.00008
0.000095000000000 0.00009
Setting mode NEAR; controlFP returned: 524319
0.000005000000000 0.00001
0.000015000000000 0.00002
0.000025000000000 0.00003
0.000035000000000 0.00004
0.000045000000000 0.00005
0.000055000000000 0.00006
0.000065000000000 0.00007
0.000075000000000 0.00008
0.000085000000000 0.00009
0.000095000000000 0.00010

[download]
Examine what is said, not who speaks -- Silence betokens consent -- Love the truth but pardon error.
"Science is about questioning the status quo. Questioning authority".
In the absence of evidence, opinion is indistinguishable from prejudice.

In reply to Re^7: RFC: Large Floating Point Numbers - Rounding Errors by BrowserUk
in thread RFC: Large Floating Point Numbers - Rounding Errors by GAVollink

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