Time Unit

{
  "data": ... ,
  "mark": ... ,
  "encoding": {
    "x": {
      "timeUnit": ...,               // time unit
      "field": ...,
      "type": "temporal",
      ...
    },
    "y": ...,
    ...
  },
  ...
}

timeUnit property of a channel definition sets the level of specificity for a temporal field. Currently supported values are:

  • Non-periodic Time Unit: 'year', 'yearmonth', 'yearmonthday', 'yearmonthdate', 'yearday', 'yeardate', 'yearmonthdayhours', 'yearmonthdayhoursminutes'.

  • Periodic Time Unit: 'month', 'day', 'date', 'hours', 'minutes', 'seconds', 'milliseconds', 'hoursminutes', 'hoursminutesseconds', 'minutesseconds', 'secondsmilliseconds'.

Example

This example shows temperature in Seattle over the months.