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Mapping Tabular Data in GIS Environment


What is Tabular Data?
Tabular data is data that looks like a table — rows and columns, just like in Excel. Each row is a different place (like a city or a school), and each column has information about that place (like population, name, rainfall, etc.).

What is Vector Data?
Vector data is the way we draw things on a map using points (like a bus stop), lines (like a road), or polygons (like a park or city area).

Now, how do we map tabular data in GIS?

Imagine you have a table like this:

City NamePopulationLiteracy Rate
Palakkad1,30,00092%
Kochi6,00,00095%

And in GIS, you have a map of Kerala showing where Palakkad and Kochi are as points (vector data).

In GIS, you "join" the table with the map.

GIS connects the rows in the table to the points on the map using a common link, like the city name. Once they are linked:

  • You can see the data on the map.

  • You can color the cities based on population or literacy.

  • You can make graphs or charts using this data.

  • You can analyze patterns, like which cities have high or low literacy.

Why is it useful?

  • Helps in visualizing data on a map.

  • Makes it easy to compare places.

  • Useful for planning, decision-making, and studies.

Example:
You can color all cities with a population above 5 lakh in red and the rest in green. This makes it very easy to spot large cities on the map.


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