Tutorial : How to Visualize Your Data in Google Maps

There is no need of using complex and expensive GIS tools to visualize a small data set (less than 500 locations). If you have a data set which contain location name or address , for e.g.  List of universities in India or List of railway stations   etc. This tutorial will help you to plot such locations in Google maps without the longitude and longitude data.

Tools used

1. OpenRefine
2. Drive.Google.com (gmail login)

Steps to install Refine

1. Download
2. Unzip installation file and follow Install Instructions to run it
3. OpenRefine runs in a web browser, and when you start it, it automatically open a  web browser window
4. or try http://127.0.0.1:3333 and you should see it.

Procedure 1:  How to Get Geographic Coordinates  from Location Description 

Step 1 :   Open the Excel file , which contain location details using OpenRefine 

Step 2: Click "Edit column -> Add column by fetching URLs"

Step 3: Enter following in Expression Column 

 http://maps.google.com/maps/api/geocode/json?sensor=false&address=" + escape(value, "url")

and give a new column name.

Step 4: To convert this data into a more readable format, you need to click on the new column, and then on " Edit column -> Add column based on this column " . Enter in the expression below

with(value.parseJson().results[0].geometry.location, pair, pair.lat +", " + pair.lng)

Step 5: Split into 2 columns

Now we have a single column with both coordinates. We can split this into columns for latitude and longitude by selecting "Edit Column -> Split into several columns" and specifying a separator of ",". Now we have the longitude and longitude details of your location data

Step 6 : Download the File - The data can be downloaded into various formats such as Excel. 

Procedure 2: How to Visualize Map using Fusion Tables

There many ways to plot the data . But I choose the easier one ,Google Fusion Tables . It is an online data management application, designed for easy analysis, visualization and publishing. 

Step 1: Open Drive.Google.com [You should have a valid Gmail Account]

Step 2: Click the Create button 
Step 3: Choose Create > More > Fusion Table from the dropdown menu

Step 4: In the Import new table dialog box, click Choose File
Step 5: Select the  file you downloaded from OpenRefine , and press Next.
Step 6: Check that the data is formatted correctly and click Next.
Step 7: Give your table a name and click Finish
Step 8: Choose Visualize > Map. -Fusion Tables auto-detects location data in a table . Your  data is now automatically translated into a map location and a map marker is placed on a Google Map for each valid location.

That's it!  Now your map is ready  enjoy !!!!! [The map with  small red placemarkers]


Map 1 : Map of Election Fund collection by AAP (clicking on Red marks gives you number of donars ,total amount and average amount)

Map 2: Map of main places in Ernakulam

Try It !!!!!!!

Reference  : 

1.  Merge tables to apply map styles by column
2. Visualize Field Data in Google Earth and Fusion Tables