...

Google Charts is a Javascript library developed by Google to visualize data. Similar to amCharts, it has a specific way it expects the data to be provided to the API in order for the charts to work. RDS provides a way to format the results in the way Google Charts expects to receive them.

...

Formatting Tabulations

• In this example we will create an object that can be used with Google Charts. We will assume that we have a collection named "test" and  and a view named "view" with  with a variable named "var" that  that has the values 1, 2, and 3. In this example we will run a tabulation that will count the frequencies of each of these values that could be used to create a chart.

• Running the tabulation would normally look something like this:

  Code Block
  title Tabulation
  http://{host}/rds/api/catalog/test/view/tabulate?dims=var

  
  

  Code Block
  title Tabulation Output collapse true
  { "records": [ [ 1, 182 ], [ 2, 354 ], [ 3, 126 ] ], "info": { "colCount": 2, "format": "MTNA", "includeMetadata": false, "limit": 20, "offset": 0, "moreRows": false } }

  
  

• We can add the format parameter to specify we want this to be output in a way that Google Charts expects to see it. 

  Code Block
  title Tabulation amCharts
  http://{host}/rds/api/catalog/test/view/tabulate?dims=var&format=gcharts

  
  

  Code Block
  title Tabulation amCharts Output collapse true
  { "cols": [ { "id": "var", "type": "number" }, { "id": "count", "type": "number" } ], "rows": [ { "c": [ { "v": 1 }, { "v": 182 } ] }, { "c": [ { "v": 2 }, { "v": 354 } ] }, { "c": [ { "v": 3 }, { "v": 126 } ] } ] }

  
  

• In addition to formatting the values into a Google Charts compliant format, we can also substitute the numeric values for the categories they represent if the variable has a classification associated with it. In this example we will assume that var has the following classification:

  1	METROPOLITAN AREA
  2	TOWN OR CITY
  3	OPEN COUNTRY

  With this in mind, all we have to do is ask for specify the metadata to be returned along with our previous tabulation and  and the output will have the categories instead of the numeric values.

  Code Block
  title Tabulation amCharts With Metadata
  http://{host}/rds/api/catalog/test/view/tabulate?dims=var&format=gcharts&metadata

  
  

  Code Block
  title Tabulation amCharts Output With Categories collapse true
  { "cols": [ { "id": "var", "type": "string" }, { "id": "count", "type": "number" } ], "rows": [ { "c": [ { "v": "METROPOLITAN AREA" }, { "v": 182 } ] }, { "c": [ { "v": "TOWN OR CITY" }, { "v": 354 } ] }, { "c": [ { "v": "OPEN COUNTRY" }, { "v": 126 } ] } ] }