Added protection against a range where xmin >= xmax
Added protection against a range where xmin >= xmax


git-svn-id: ecbadac9c76e8cf640a0bca86f6bd796c98521e3@11626 27541ba8-7e3a-0410-8455-c3a389f83636

dawehner/root,dawehner/root,bbannier/ROOT,dawehner/root,dawehner/root,dawehner/root,dawehner/root,dawehner/root,bbannier/ROOT,bbannier/ROOT,bbannier/ROOT,bbannier/ROOT,bbannier/ROOT,bbannier/ROOT,dawehner/root