Which process reduces the number of points in a polyline while preserving its overall shape?

• A. generalization
• B. resampling
• C. neighborhood analysis
• D. interpolation

Answer: (A)

Generalization is the process of simplifying a polyline by trimming away less critical points while keeping the overall form recognizable. By removing vertices that contribute little to the shape, you reduce data size but preserve the essential path, so a coastline or road path remains identifiable even after simplification. Algorithms like Douglas-Peucker work by defining a tolerance and removing points that keep the line within that tolerance of the original, yielding a simpler version that looks like the original at a coarser scale.

Resampling changes how points are spaced along the line, which can increase or adjust point density without necessarily simplifying the shape. Neighborhood analysis examines spatial relationships within a local area rather than altering the geometry of the polyline. Interpolation estimates new points between known ones to create a continuous surface or line, which adds points rather than reducing the existing ones.