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#include <bu/sio.h>
#include <bu/string.h>
#include <stdlib.h>
#include <math.h>
using namespace Bu;
Bu::String ftos( double dNum )
{
if( dNum == 1.0 )
return "0x1p+0";
if( dNum == 0.0 )
return signbit(dNum)?"-0x0p+0":"0x0p+0";
if( dNum == -1.0 )
return "-0x1p+0";
Bu::String s("0x1.");
if( signbit(dNum) )
{
s.prepend("-");
dNum = -dNum;
}
/*
for( int j = 0; j < 150 && dNum; j++ )
{
dNum = dNum*2;
sio << dNum << " -- " << (int)dNum << sio.nl;
if( (int)dNum == 0 )
s += '0';
else
{
s += '1';
dNum -= 1.0;
}
}
return s;
*/
int iPower = 0;
if( dNum < 1.0 )
{
while( dNum < 1.0 )
{
dNum *= 2.0;
iPower--;
}
}
else if( dNum >= 2.0 )
{
while( dNum >= 2.0 )
{
dNum *= 0.5;
iPower++;
}
}
dNum -= (int)dNum;
for( int j = 0; j < 150 && dNum; j++ )
{
dNum = dNum*16.0;
s += "0123456789abcdef"[(int)dNum];
dNum -= (int)dNum;
}
s.formatAppend("p%+d", iPower );
return s;
}
double stof( const Bu::String &s )
{
if( s == "0x1p+0" )
return 1.0;
if( s == "-0x1p+0" )
return -1.0;
if( s == "0x0p+0" )
return 0.0;
if( s == "-0x0p+0" )
return 0.0;
double dNum = 0.0;
int iPPos = s.getSize()-1;
for(; s[iPPos] != 'p'; iPPos--) { }
for( int i = iPPos-1; s[i] != '.'; i-- )
{
if( s[i]>='0' && s[i]<='9' )
{
dNum += s[i]-'0';
}
else if( s[i]>='a' && s[i]<='f' )
{
dNum += s[i]-'a'+10.0;
}
dNum *= 0.0625;
}
dNum += 1.0;
int iTop = strtol( s.getStr()+iPPos+1, NULL, 10 );
if( iTop < 0 )
{
for( int j = 0; j > iTop; j-- )
{
dNum *= 0.5;
}
}
else
{
for( int j = 0; j < iTop; j++ )
{
dNum *= 2.0;
}
}
if( s[0] == '-' )
return -dNum;
return dNum;
}
int main( int argc, char *argv[] )
{
for( int j = 1; j < argc; j++ )
{
double dNum = strtod( argv[j], NULL );
String s = ftos( dNum );
sio << "in: " << dNum << sio.nl;
sio << "mine: " << s << sio.nl;
printf("printf: %a\n", dNum );
sio << "out: " << stof( s ) << sio.nl;
sio << "match: " << (stof( s ) == dNum) << sio.nl << sio.nl;
}
return 0;
}
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