static
istream & HexInput(istream& s, GF2X& a)
{
long n;
long c;
long i;
long val;
GF2X ibuf;
n = 0;
clear(ibuf);
c = s.peek();
val = CharToIntVal(c);
while (val != -1) {
for (i = 0; i < 4; i++)
if (val & (1L << i))
SetCoeff(ibuf, n+i);
n += 4;
s.get();
c = s.peek();
val = CharToIntVal(c);
}
a = ibuf;
return s;
}
void conv(RR& x, const char *s)
{
long c;
long cval;
long sign;
ZZ a, b;
long i = 0;
if (!s) Error("bad RR input");
c = s[i];
while (IsWhiteSpace(c)) {
i++;
c = s[i];
}
if (c == '-') {
sign = -1;
i++;
c = s[i];
}
else
sign = 1;
long got1 = 0;
long got_dot = 0;
long got2 = 0;
a = 0;
b = 1;
cval = CharToIntVal(c);
if (cval >= 0 && cval <= 9) {
got1 = 1;
while (cval >= 0 && cval <= 9) {
mul(a, a, 10);
add(a, a, cval);
i++;
c = s[i];
cval = CharToIntVal(c);
}
}
if (c == '.') {
got_dot = 1;
i++;
c = s[i];
cval = CharToIntVal(c);
if (cval >= 0 && cval <= 9) {
got2 = 1;
while (cval >= 0 && cval <= 9) {
mul(a, a, 10);
add(a, a, cval);
mul(b, b, 10);
i++;
c = s[i];
cval = CharToIntVal(c);
}
}
}
if (got_dot && !got1 && !got2) Error("bad RR input");
ZZ e;
long got_e = 0;
long e_sign;
if (c == 'e' || c == 'E') {
got_e = 1;
i++;
c = s[i];
if (c == '-') {
e_sign = -1;
i++;
c = s[i];
}
else if (c == '+') {
e_sign = 1;
i++;
c = s[i];
}
else
e_sign = 1;
cval = CharToIntVal(c);
if (cval < 0 || cval > 9) Error("bad RR input");
e = 0;
while (cval >= 0 && cval <= 9) {
mul(e, e, 10);
add(e, e, cval);
i++;
c = s[i];
cval = CharToIntVal(c);
}
}
if (!got1 && !got2 && !got_e) Error("bad RR input");
RR t1, t2, v;
long old_p = RR::precision();
if (got1 || got2) {
ConvPrec(t1, a, max(NumBits(a), 1));
ConvPrec(t2, b, NumBits(b));
if (got_e)
RR::SetPrecision(old_p + 10);
div(v, t1, t2);
}
else
set(v);
if (sign < 0)
negate(v, v);
if (got_e) {
if (e >= NTL_OVFBND) Error("RR input overflow");
long E;
conv(E, e);
if (e_sign < 0) E = -E;
RR::SetPrecision(old_p + 10);
power(t1, to_RR(10), E);
mul(v, v, t1);
RR::prec = old_p;
}
xcopy(x, v);
}
