Fatal error: Uncaught Error: Class "Matrix\Operators\Operator" not found in /var/www/u0689339/data/www/prog01.ru/vendor/markbaker/matrix/classes/src/Operators/DirectSum.php:8 Stack trace: #0 {main} thrown in /var/www/u0689339/data/www/prog01.ru/vendor/markbaker/matrix/classes/src/Operators/DirectSum.php on line 8