ASTNode node = new ASTNode(ASTNode.Type.FUNCTION_PIECEWISE);
ASTNode floorNode = new ASTNode(ASTNode.Type.FUNCTION_FLOOR);
ASTNode aDividedByB = new ASTNode(ASTNode.Type.DIVIDE);
aDividedByB.addChild(leftChild);
aDividedByB.addChild(rightChild);
floorNode.addChild(aDividedByB);
node.addChild(floorNode);
ASTNode greaterThan = new ASTNode(ASTNode.Type.RELATIONAL_GT);