INTRODUCTION TO GEOSPATIAL AND ARCGIS DATA

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Data Type

Data in a Geographic Information System (GIS) is geographically oriented data, has a certain coordinate system as its reference base and has two important parts that make it different from other data, namely: spatial information (location) and attribute information (descriptive). Input data in GIS can be in the form of: maps (analog or digital), field measurements, GPS data, aerial photographs and satellite imagery, Digital Elevation Model (DEM), statistical data in the form of reports and tables, and various other types of data. Simply put, the data format in GIS, spatial data can be represented in two formats, namely: vector data and raster data

Vector Data

Vector data is the shape of the earth which is represented in the form of points, lines and areas (areas bounded by lines that start and end at the same point), points and nodes (which are the point of intersection between two lines).

The main advantages of vector data formats are: accuracy in representing point, line and area features which are very useful for analyzes that require positional accuracy such as cadastral boundary databases, can define spatial relationships of several features, while the main weakness of vector data is its inability to accommodate gradual changes. .


Raster Data

Raster data is represented as pixels (picture elements), where the pixel resolution describes the objects on the earth's surface represented by each pixel in the image so the smaller the size of the earth's surface represented by a single cell, the higher the resolution.


Raster Data

Raster data is very good for representing gradually changing boundaries, such as soil type, soil moisture, vegetation, soil temperature and so on while the main limitation of raster data is the large file size; The higher the pixel resolution, the larger the file size.

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