The pos() operator allows you to search for an item within a field by specifying the position in the field. The syntax for this operator is pos(fieldedquery,position,[endposition]). If no endposition is given, then it is assumed to be endposition = position, otherwise this performs a query within the range [position, endposition]. For example:
|pos(author:”Oort, J”,2)||papers which have “J. Oort” as the second author|
|pos(author:”Oort, J”,2,2)||same as above|
|pos(author:”Oort, J”,1,3)||papers which have “J. Oort” as first, second, or third author|
|pos(aff:harvard,1)||papers for which the first author has a Harvard affiliation|
|pos(title:M31,1)||papers for which the title start with “M31”|
Currently the pos() operator works on these fields: author, aff, title.