Thus, you should choose a cell size appropriate to the feature that the point represents. Point data features will become the size of the cell. It is possible to have fewer cells with values than there are points being converted. However, when using the Point To Raster tool, you can choose the type of cell value assignment. In general, if two or more points fall within the extent of a cell, ArcGIS randomly selects one of the points when assigning a value to the cell. With a cell representation of point data, there is some generalization of the original data. For example, it is assumed that a well, a telephone pole, or the location of an endangered plant occupies the entire area covered by a cell. Therefore, the smaller the cell size, the smaller the area and, thus, the closer the representation of the point feature. By definition, a point has no area but is converted to a cell representing area. PointsĪ point is represented by an explicit x,y coordinate in vector format, but as a raster, it is represented as a single cell-the smallest unit of a raster.
Raster data is best used when your primary concern is with the locational relationships of the phenomena represented by geographic features and not the features themselves. As a result, when representing geographic features in a raster dataset, they become collections of cells with the same attribute values but lose their unique identities. In raster data, the cell typically represents the predominant feature or phenomenon of the area covered by a cell, whereas vector data can accurately delineate or identify individual features.
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