Question regarding population.json / grouped bar chart

[vikpe]

Is repetition of data required in order to create a grouped bar chart?

In the data file population.json from the example, data is repeated for each sex.

[  
   {  
      "year": 1850,
      "age": 0,
      "sex": 1,
      "people": 1483789
   },
   {  
      "year": 1850,
      "age": 0,
      "sex": 2,
      "people": 1450376
   }
]

The data could be defined as (and reduce file by 50%):

[  
   {  
      "year": 1850,
      "age": 0,
      "men": 1483789,
      "women": 1450376
   }
]

[domoritz]

Yes, for now that is the case. The size of the spec has very little effect on the performance so I wouldn't worry about it.

[vikpe]

@domoritz Ok, thank you!

[kanitw]

Note that the data in this "long" format

[  
   {  
      "year": 1850,
      "age": 0,
      "sex": 1,
      "people": 1483789
   },
   {  
      "year": 1850,
      "age": 0,
      "sex": 2,
      "people": 1450376
   }
]

is considered cleaner/tidier as all keys are variable names and all values are the actual values.

That said, in the future, you will be able to create a grouped bar chart for the short form using facet of a concatenated bar. But we currently don't support it yet (#2760).

[vikpe]

@kanitw "Tidy data" is a very interesting article. It might be a good idea to reference it in the data docs.

[kanitw]

Sure, feel free to submit a PR to suggest edits.