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/*
A test program to which explores the ability to round trip a nanometer
internal unit in the form of a 32 bit int, out to ASCII floating point
millimeters and back in without variation. It tests all 4 billion values
that an int can hold, and converts to ASCII and back and verifies integrity
of the round tripped value.
Author: Dick Hollenbeck
*/
#include <limits.h>
#include <stdio.h>
#include <cmath>
#include <string>
#include <string.h>
#include <stdlib.h>
#include <stdint.h>
static inline int KiROUND( double v )
{
return int( v < 0 ? v - 0.5 : v + 0.5 );
}
typedef int BIU;
#define BIU_PER_MM 1e6
//double scale = BIU_PER_MM;
//double scale = UM_PER_BIU;
double scale = 1.0/BIU_PER_MM;
std::string biuFmt( BIU aValue )
{
double engUnits = aValue * scale;
char temp[48];
int len;
if( engUnits != 0.0 && fabsl( engUnits ) <= 0.0001 )
{
len = snprintf( temp, sizeof( temp ), "%.10f", engUnits );
while( --len > 0 && temp[len] == '0' )
temp[len] = '\0';
++len;
}
else
{
len = snprintf( temp, sizeof( temp ), "%.10g", engUnits );
}
return std::string( temp, len );;
}
int parseBIU( const char* s )
{
double d = strtod( s, NULL );
return KiROUND( double( d * BIU_PER_MM ) );
// return int( d * BIU_PER_MM );
}
int main( int argc, char** argv )
{
unsigned mismatches = 0;
if( argc > 1 )
{
// take a value on the command line and round trip it back to ASCII.
int i = parseBIU( argv[1] );
printf( "%s: i:%d\n", __func__, i );
std::string s = biuFmt( i );
printf( "%s: s:%s\n", __func__, s.c_str() );
exit(0);
}
// printf( "sizeof(long double): %zd\n", sizeof( long double ) );
// Emperically prove that we can round trip all 4 billion 32 bit integers representative
// of nanometers out to textual floating point millimeters, and back without error using
// the above two functions.
// for( int i = INT_MIN; int64_t( i ) <= int64_t( INT_MAX ); ++i )
for( int64_t j = INT_MIN; j <= int64_t( INT_MAX ); ++j )
{
int i = int( j );
std::string s = biuFmt( int( i ) );
int r = parseBIU( s.c_str() );
if( r != i )
{
printf( "i:%d biuFmt:%s r:%d\n", i, s.c_str(), r );
++mismatches;
}
if( !( i & 0xFFFFFF ) )
{
printf( " %08x", i );
fflush( stdout );
}
}
printf( "mismatches:%u\n", mismatches );
return 0;
}
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