cfad47cfa3/t3compiler/tads3/test/data/mod_bignum.t

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#include "tads.h"



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#include "t3.h"



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#include "bignum.h"



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preinit()



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{



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}



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main(args)



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{



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    local x;



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    x = 1.00000000000e8 / 3;



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    tadsSay(x.spellNumber());



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    "\b";



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    "log2(32) = << (32.0000).log2() >>\n";



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    "log2(55) = << (55.0000000).log2() >>\n";



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}



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modify BigNumber



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    log2()



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    {



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        /* 



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         *   cache ln(2) with slightly greater precision than our value -



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         *   if we already have a precise enough value cached, there's no



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         *   need to cache it again 



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         */



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        if (BigNumber.cacheLn2_ == nil



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            || BigNumber.cacheLn2_.getPrecision() < getPrecision() + 3)



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            BigNumber.cacheLn2_ = new BigNumber(2, getPrecision() + 3).logE();



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        /* 



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         *   calculate ln(self) to slightly greater than the required



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         *   precision, to avoid rounding error, then divide by the cached



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         *   value of ln(2) to yield the log base 2 of self 



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         */



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        return (self.setPrecision(getPrecision() + 3).logE()



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                / BigNumber.cacheLn2_).setPrecision(getPrecision());



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    }



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    cacheLn2_ = nil



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    spellNumber()



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    {



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        local str;



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        local val = self;



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        local units = ['one', 'two', 'three', 'four', 'five',



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                       'six', 'seven', 'eight', 'nine', 'ten'];



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        /* start out with an empty string */



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        str = '';



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        /* if the value is exactly zero, it's a special case */



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        if (val == 0.0)



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            return 'zero';



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        /* 



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         *   if it's negative, start the string with 'minus' and change



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         *   the value we're working with to positive 



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         */



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        if (val < 0.0)



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        {



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            str = 'minus ';



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            val = -val;



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        }



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        /* do the billions */



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        if (val > 1.0e9)



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        {



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            /* add the billions */



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            str += (val / 1.0e9).getWhole().spellNumber() + ' billion ';



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            /* remove the billions portion */



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            val -= (val / 1.0e9).getWhole() * 1.0e9;



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        }



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        /* do the millions */



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        if (val > 1.0e6)



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        {



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            /* add the millions */



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            str += (val / 1.0e6).getWhole().spellNumber() + ' million ';



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            /* remove the millions portion */



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            val -= (val / 1.0e6).getWhole() * 1.0e6;



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        }



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        /* do the thousands */



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        if (val > 1.0e3)



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        {



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            /* add the number of thousands */



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            str += (val / 1.0e3).getWhole().spellNumber() + ' thousand ';



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            /* remove the thousands */



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            val -= (val / 1.0e3).getWhole() * 1.0e3;



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        }



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        /* do the hundreds */



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        if (val > 100.0)



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        {



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            /* add the number of hundreds */



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            str += units[toInteger(val / 100.0)] + ' hundred ';



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            /* remove the hundreds */



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            val -= (val / 100.0).getWhole() * 100.0;



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        }



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        /* do the rest */



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        if (val >= 20.0)



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        {



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            /* add the tens name */



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            str += ['twenty', 'thirty', 'forty', 'fifty', 'sixty',



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                    'seventy', 'eighty', 'ninety']



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                   [toInteger(val / 10.0) - 1];



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            /* remove the tens */



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            val -= (val / 10.0).getWhole() * 10.0;



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            /* if there's anything left, add it */



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            if (val != 0)



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                str += '-' + units[toInteger(val)];



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        }



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        else if (val >= 10.0)



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        {



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            /* add the 'teen' name */



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            str += ['ten', 'eleven', 'twelve', 'thirteen', 'forteen',



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                    'fifteen', 'sixteen', 'seventeen', 'eighteen',



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                    'nineteen'][toInteger(val) - 9];



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        }



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        else if (val >= 0.0)



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        {



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            /* only the units remain */



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            str += units[toInteger(val)];



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        }



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        else



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        {



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            /* 



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             *   we're not adding anything more - we left a trailing space



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             *   in case we were going to add something, so remove it 



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             */



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            str = str.substr(1, str.length() - 1);



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        }



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        /* return the result */



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        return str;



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    }



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;



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