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/*  I always end up need this for debugging */ { ulp32(a) = my(aa, q);        aa = abs(a);        if(aa < 2^(-150),return(2^(-126 - 23)),);        q = floor(log(aa)/log(2));        if(q < -126,q=-126,);        return(2^(q-23));} { ulp64(a) = my(aa, q);        aa = abs(a);        if(aa < 2^(-2000),return(2^(-1022 - 52)),);        q = floor(log(aa)/log(2));        if(q < -1022,q=-1022,);        return(2^(q-52));} { err32(x, y) =        return(abs(x-y)/ulp32(x));} { err64(x, y) =        return(abs(x-y)/ulp64(x));} { flt32fromuint32(a) = my(n, e, s);        n = bitand(a, 0x80000000) != 0;        e = bitand(a, 0x7f800000) >> 23;        s = bitand(a, 0x007fffff);         if(e != 0, s = bitor(s, 0x00800000), s = 2.0 * s);        s = s * 2.0^(-23);        e = e - 127;        return((-1)^n * s * 2^(e));} { flt64fromuint64(a) = my(n, e, s);        n = bitand(a, 0x8000000000000000) != 0;        e = bitand(a, 0x7ff0000000000000) >> 52;        s = bitand(a, 0x000fffffffffffff);         if(e != 0, s = bitor(s, 0x0010000000000000), s = 2.0 * s);        s = s * 2.0^(-52);        e = e - 1023;        return((-1)^n * 2^(e) * s);}