graph(Noun) An ordered pair , where is a set of elements called vertices (or nodes) and is a set of pairs of elements of , called edges; informally, a set of vertices together with a set edges that join these vertices.
Clubbing is an enlargement of the ends of the fingers and a downward sloping of the nails. Although it's not caused by chronic obstructive pulmonary disease (COPD), it can be a sign of coexisting lung cancer or other lung disorders in patients with COPD. Clubbing is sometimes called digital clubbing. It can affect the fingers and/or toes.
Other Causes: Spoon-shaped nails. Some of the less common causes of Spoon-shaped nails may include: 1  Hemochromatosis. 2  Raynaud's disease. 3  SLE. 4  Trauma. 5  Nail-patella syndrome. 6  Physiologic occurrence in children.