1. INTEGRATED ANALYSIS OF SPATIAL AND
NON SPATIAL DATA
By
Mohammed Akram Ullah Khan
Senior Geologist,
TerraWorld.
2. INTRODUCTION:-
Geographic Information Systems (GIS) analysis
functions use spatial and non-spatial attribute
data to answer questions about the real world.
It is the spatial analysis functions that distinguish
a GIS from other information type systems.
Wise use and selection of these functions will
lead to high quality of the information produced
from the GIS.
3. DEFINITION OF GIS:-
A geographic information system, or GIS, is a
computerized data management system used to
capture, store, manage, retrieve, analyze, and
display spatial information.
Data captured and used in a GIS commonly are
represented on paper or other hard-copy maps.
4. SPATIAL ANALYSIS :-
Spatial analysis or spatial statistics includes any
of the formal techniques which study entities
using their topological, geometric, or geographic
properties.
Spatial analyses are quantitative techniques and
procedures used to analyze the pattern of the
spatial data.
5. NETWORK ANALYSIS :-
Designed specifically for line features organized in
connected networks, typically applies to transportation
problems and location analysis such as school bus routing,
passenger plotting, walking distance, bus stop
optimization, optimum path finding etc.
Figure shows a common application of GIS-based network
analysis. Routing is a major concern for the transportation
industry.
A spatial analysis function that uses the topological
structure of lines to follow a path along an interconnected
network and then process attribute data associated with
the line segments.
The GIS process providing analytical techniques for
geographic or statistical analysis of relationships and flow
that are dependent on the connectivity of segments and
nodes in a linear system.
6. Figure: The most cost effective route
links five point locations on the street
map
8. SPATIAL DATA :-
It is the data or information that identifies the
geographic location of features and boundaries on Earth ,
such as natural or constructed features, oceans , and
more .
Spatial data is usually stored as coordinate and topology,
and is data that can be mapped.
Spatial data includes location, shape, size, and
orientation.
Spatial data includes spatial relationships. For example,
the arrangement of ten bowling pins is spatial data.
9. In GIS, there are 2 basic spatial data types
Raster Vector
SPATIAL DATA TYPES:-
10. RASTERS DATA :-
cell –based data such as aerial imagery and digital
elevation models. Raster data is characterized by pixel
values. Basically, a raster file is a giant table, where
each pixel is assigned a specific value from 0 to 255.
The meaning behind these values is specified by the user
– they can represent elevations, temperature, hydrology
and etc.
11. VECTOR DATA :-
Vector data provide a way to represent real world features within
the GIS environment. A vector feature has its shape represented
using geometry. The geometry is made up of one or more
interconnected vertices. A vertex describe a position in space
using an x, y and optionally z axis. In the vector data model,
features on the earth are represented as:
• points
• lines / routes
• polygons / regions
• TINs (triangulated irregular networks)
12. VECTOR DATA :-
This system of recording features is based on the
interaction between arcs and nodes, represented by points,
lines and polygons. A point is a single node, a line is two
nodes with an arc between them, and a polygon is a closed
group of three or more arcs. With these three elements , it
is possible to record most all necessary information.
Points Lines Polygons
15. SPATIAL DATA FUNCTION:-
Format transformations
Geometric transformations
Projection transformations
Conflation
Line coordinate thinning
16. NON SPATIAL DATA :-
Data that relate to a specific, precisely defined location.
The data are often statistical but may be text, images or
multi-media. These are linked in the GIS to spatial data
that define the location.
Non-spatial data (also called attribute or characteristic
data) is that information which is independent of all
geometric considerations.
For example, a person’s height, mass, and age are non-
spatial data because they are independent of the person’s
location.
It’s interesting to note that, while mass is non-spatial
data, weight is spatial data in the sense that something’s
weight is very much dependent on its location.
17. NON SPATIAL FUNCTION:-
Attribute Data is relate to the description of the
map items. It is typically stored in tabular format
and linked to the feature by a user-assigned
identifier
19. INTEDRATED ANALYSIS OF SPATIA AND
NON SPATIAL DAYTA :-
Retrieval/classification/measurement
Overlay
Neighborhood
Point-in-polygon and Line-In-Polygon
Connectivity of network function
20. Retrieval/classification/measurement:-
Retrieval:-
Retrieval operations on the spatial and attribute data involve
the selective search manipulation . The output of selective search
can create new layers in the database, tabular reports, interaction
displays or maps.
Classification/Reclassification:-
Classification is the procedure of identifying a set of features
as belonging to a group and defined patterns . Some form of
classification function is provided in every GIS . In a raster-based
GIS, numerical values are after used to indicate classes.
Measurement:-
Measure functions calculate distances between points, lengths
of lines, perimeters and area of polygons and sizes of continuous
area of the same feature.
21. Overlay:-
Overlay operators are some of the most fundamental and
most frequently used processes in GIS application.
Generally there are two types.
They are
Arithmetic overlay operations:-
Arithmetic operators used to add, subtract, divide or
multiply values in one data layer by a constant or values
in another data layer in corresponding location.
+ =
Input data layer A Input data layer B
Output data layer
4 5
9
22. Neighborhoods:-
Neighborhood process evaluates the characteristics of the
area surrounding a specific location.
Neighborhood function analysis the relationship between
an object and similar surround objects.
This type of analysis often used in image processing.
Measuring the length of edge between habitat types
within 2 km of the location of a radio telemeter animal is
an example of a neighborhood function.
23. POINT-IN-POLYGON AND
LINE –IN-POLYGON :-
Point-in-polygon is a topological overlay procedure which
determines the spatial coincidence of points and
polygons. Point’s area assigned the attribute of the
polygons within which they fall.
For example, this function can be used to analyze an
address and find out if it (point) is located within zip code
area.
24. Line-in polygon is a spatial operation in which lines in one coverage
are overlaid with polygons of coverage to determine which lines, or
portions of lines, are contained within the polygons. Polygon
attributes are associated with corresponding lines in the resulting
line coverage.
25. CONNECTIVITY OF NETWORK FUNCTION:-
Connectivity functions accumulate values over a
connected area. Connectivity function required.
A produce for connecting the areas and
A measurement for the connected area.
Connectivity measures area connectivity functions that
typically measure the size of a continuous area.
Connectivity measures are valuable tools for measuring
habitat fragment
26. CONCLUSIONS:-
GIS is considered as a decision making tool in problem
solving environment. Spatial analysis is a vital part of GIS
and can be used for many applications like site suitability,
natural resource monitoring, environmental disaster
management and many more. Vector, raster based analysis
functions and arithmetic, logical and conditional
operations are used based on the recovered derivations.