public static String toString(long[] xs, int begin, int end, String var) {
StringBuilder buffer = new StringBuilder();
try {
if (!Euclid.toString(buffer, xs, begin, end, var)) {
buffer.append("0");
}
} catch (IOException ex) {
ex.printStackTrace();
}
return buffer.toString();
}
public static String toString(long[] xs, String var) {
return Euclid.toString(xs, 0, xs.length, var);
}
public static boolean toString(
Appendable writer, long[] xs0, long[] xs1, int begin, int end, String var)
throws IOException {
end = highest(xs0, begin, end);
if (end < begin + 1) {
return false;
}
boolean first = true;
while (begin < end--) {
long x0 = xs0[end];
long x1 = xs1[end];
if (x0 == 0) {
continue;
} else if (x0 == x1) {
x0 = 1;
x1 = 1;
} else if (x0 == -x1) {
x0 = -1;
x1 = 1;
} else if (x1 < 0) {
x0 = -x0;
x1 = -x1;
}
boolean minus = x0 < 0;
if (minus) {
x0 = -x0;
}
if (first) {
first = false;
if (minus) {
writer.append("- ");
}
if (begin == end) {
toString(writer, x0, x1);
} else {
if (x0 != x1) {
toString(writer, x0, x1);
}
writer.append(var);
if (begin + 1 < end) {
writer.append('^');
writer.append(Integer.toString(end));
}
}
} else {
if (minus) {
writer.append(" - ");
} else {
writer.append(" + ");
}
if (end == 0 || x0 != x1) {
toString(writer, x0, x1);
}
switch (end - begin) {
case 0:
break;
case 1:
writer.append(var);
break;
default:
writer.append(var);
writer.append('^');
writer.append(Integer.toString(end - begin));
break;
}
}
}
return true;
}