"Source: Text/LieTheory/Cartan.text";
"Line: 108";
"Date: Tue Jun  7 22:27:15 2016";
"Main: Thu May 25 10:02:38 2023";
// original file: Text/LieTheory/Cartan.text, line: 108
// Example: H102E1 ()
print "Example: H102E1";
ei := GetEchoInput();
SetEchoInput(true);
M := SymmetricMatrix([1, 3,1, 2,3,1]);
M;
IsCoxeterMatrix(M);
assert $1;
SetEchoInput(ei);
