doc2 = database.getDocumentByUNID(viewScope.doc2); 

 

doc2.replaceItemValue("Body",   "some content"); 

doc2. replaceItemValue ("Number",  2); 

 

 

if you set a property to compute in the properties panel and open the script editor there is a reference list of the javascript methods that can be called, can be helpful to find out whats available