Both raster and vector data models each have characteristics or tendencies, its own advantages and disadvantages. Nevertheless, bearing in mind that the objective nature and human needs can be different from each other and even changed from time to time, then none of the data model that really can meet all the needs of the representation and analysis of spatial data perfectly. Thus, both the data model will be complementary and even mutually converted to each other (raster to vector or vector to raster).
a. Raster Data
Advantages :
- Has a simple data structure
- Easily manipulated using simple mathematical functions
- The technology used is quite cheap and not so complex that user.
- Can create your own application programs using raster image.
- Compatible with images of satellite remote sensing and image scanning results all spatial data.
- Overlay and the combination of raster data with remote sensing of data is easy to do
- Have a modeling capabilities and advanced spatial analysis.
- Methods to obtain raster image easier
- Picture of the earth’s surface in the form of a raster image obtained from radar or satellite remote sensing is always more actual than the shape of the vector
- The procedure for obtaining data in raster form is easier, simpler and cheaper.
- Price system software applications tend to be cheaper.
Deficiency :
- Generally requires a space or a place to store (disk) which is great in the computer, many occur redudacy data both for each layer of his or overall.
- The use of cell or large lebiih grid size to save storage space will cause the loss of information and accuracy.
- A raster image contains only one thematic course so difficult to combine with other attributes in a single layer.
- Appearance or representation and positioning accuracy is very dependent on the size of the pixel (spatial resolution).
- Often experience an error in describing the shape and boundaries of an object, highly dependent on the spatial resolution and a given tolerance.
- Coordinate transformation and projections more difficult
- Very difficult to represent the topological relations (also network).
- Methods to obtain vector data formats through a long process, is quite laborious and relatively expensive.
b. Vector Data
Advantages :
- Require space or a place to store fewer computers. One layer can be associated with or using attributes so as to save storage space as a whole.
- With many of the attributes that many contained by one layer, many other thematic maps that can be generated as a map derivatives.
- Relationships and network topology can be done easily. Has a high spatial resolution.
- Graphical representation of spatial data is very similar to human hands garisbuatan map.
- Have limits of conscientious, firm and clear so it is good for the creation of maps and plots of land belonging to the administration.
- Coordinate transformation and the projection is not hard to do.
Deficiency :
- Has a complex data structures.
- The data are not easy to manipulate.
- Users are not easy to be creative to create its own program to meet the needs of the application. Hali is due to the vector data structures more complex and procedures and analysis functions requiring high capability because it is more difficult. The user must buy the software system because the technology is still expensive.
- The procedure was sometimes more difficult. Because the whole process to get longer, vector maps often have out of date or expired.
- Requires hardware and software more expensive.
- Vector overlay multiple layers simultaneously require a relatively long time.
As an illustration, here is a view that contains the elements of spatial geometries point, line and polygon both in raster and vector data model.
Figure 6. Example of the display raster and vector data model