These directions use sample bus departures data, where the 24 hour timestamp is saved in a numeric field, such as 835 for 8:35 am. You may not need all of the following steps if your 24 hour timestamp is already a string field (aka text type) with a leading zero. 

1. Right-click [Scheduled Departure Time] in the left-hand data pane and select Convert to Dimension
2. Click the # icon next to [Scheduled Departure Time] in the data pane, and select String
3. Select Analysis > Create Calculated Field
4. In the Calculated Field dialog box that opens, do the following, and then click OK:
   1. Name the calculated field. In this example, the calculated field is named "Scheduled Departure Time (dateparse)"
   2. In the formula field, create a calculation similar to the following:

      DATEPARSE("hmm",[Scheduled Departure Time])
      //if the data contains a leading zero then use "hhmm" instead of "hmm"
      

   3. DATEPARSE() is not available in all data sources. If DATEPARSE() is not available then use DATETIME() instead. In this example, the calculated field "Scheduled Departure Time (datetime)" uses the following calculation: 

      DATETIME(
          "1/1/1900 " //arbitrary date
          + IF LEN([Scheduled Departure Time]) = 3
          THEN "0"
          ELSE ""
          END //add a leading zero if the timestamp is only 3 characters long
          + [Scheduled Departure Time]
      )
      

5. Right-click [Scheduled Departure Time (dateparse)] or [Scheduled Departure Time (datetime)] in the left-hand data pane, and select Default Properties > Date Format...
6. In the Default Date Format dialog, do the following and click OK:
   1. Click Custom
   2. In the Format field, type in the desired time format such as hh:nn AMPM. See Supported date format symbols for all possible options.