Lec_1_Shapefile

Introduction to ShapefileProf. Dr. Sajid Rashid Ahmad

[email protected]

Atiqa Ijaz Khan _ Demonstrator

[email protected]

Wednesday, April 12, 20233rd Prof. BS. Applied Geology, Inst. of Geology, University of the Punjab

2Shapefile

• “Shapefile is a simple, non-topological (No Neighborhood) format for storing the geometric locations/spatial features (associated with lat/long.) and attribute information of geographic features (features on Earth surface).”

• It can support: Point, Line, and Polygon.

• Geometry is stored as ‘Shape’ format.

• Attributes are stored in dBASE format file.

• They stored projection or coordinate system as ‘.prj’ format file.


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POINT

POLYGON

LINE


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Highlighted Features

Attribute Table


7WHY shapefile?

• As it does not hold topology so it draws faster.

• It can be easily copied.

• Dose not required importing and exporting.

• Hold one-to-one relationship with spatial features.

• Supported by number of software.


8Shapefile Extensions

• It consists of 3 core extensions:• Maine File (.shp)• Index File (.shx)• dBASE File (.dbf)

• And, 3 other extensions named as:• Projection File (.prj)• Spatial Index (.sbn)• Spatial Index (.sbx)


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10Shapefile Requirements

• In order to create shapefile, following are the required parameters:• Type of Feature (point, line or polygon)• Coordinate system• 3-D values (Z-values)• Route values (M-values)

• These values are define at first, and will not alter after that.!


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Education

Lec_1_Shapefile