Resolved - I have used PHx to output the date.
I am using Ditto to build a simple list of events, and have followed the instructions found here to achieve it:
http://modxguides.com/modx1x/create-an-event-a-simple-event-calendar-with-ditto
I’ve set my event date TV up using the Unixtime widget to get the Ditto call working to produce a list of events. However, I want to be able to click on an event to view the full details, including the event date.
If my event page just outputs the date field, this is in unix time, rather than a human-readable format.
To get around this, I have tried to create another ditto call to read the date from the TV and output it on the same page, but I get "No documents found".
My page template includes a chunk: <div class="bigdate">{{eventdate}}</div>
The eventdate chunk is set up as [!Ditto? &dateFormat=`%b %d` &tpl=`single_event_tpl` &dateSource=`eventdate`]]
The single_event_tpl is: <p>[+date+]</p>
I thought that by leaving &parents out of the ditto call, it would default to the current document, so read the eventdate value from the current page?
Could someone help me with what I have done wrong please?