To maintain shape similarity of features is one of evaluation criteria before or after in map generalization. The article derives shape similarity of line-feature from shape descriptor of polygon--rebuilds conjugate polygon of line-feature consisting of mirroring-part of original feature using the axis of symmetry through the first point and the end point of itself, gets a shape vector of the line feature, which is the shape descriptor of its conjugate polygon and further requires the similarity distance among line-features through Euclidean distance between two vectors. To ensure certain eval...
