"Source: Text/LieTheory/GrpCox.text";
"Line: 1541";
"Date: Wed Nov  6 12:03:34 2019";
"Main: Thu May 25 10:02:38 2023";
// original file: Text/LieTheory/GrpCox.text, line: 1541
// Example: H105E19 ()
print "Example: H105E19";
ei := GetEchoInput();
SetEchoInput(true);
W := RootDatum("G2");
Sum(W, 1, Negative(W,5));
assert $1 eq 10;
IsPositive(W, 10);
assert not $1;
Negative(W, 10);
assert $1 eq 4;
P := PositiveRoots(W);
P[1] - P[5] eq -P[4];
assert $1;
SetEchoInput(ei);
