Question: Is Lewiston not 20 meters above sea level ?
Choices:
yes
no
unknown
unknown
unknown
unknown
unknown
unknown
unknown
unknown
Answer: yes
SPARQL: ASK { ?e <pred:name> "Lewiston" . ?e <elevation_above_sea_level> ?pv . ?pv <pred:unit> "metre" . ?pv <pred:value> ?v . FILTER ( ?v != "20"^^xsd:double ) .  }
Program:
function: Find
inputs: Lewiston
function: QueryAttr
dependencies: 0
inputs: elevation above sea level
function: VerifyNum
dependencies: 1
inputs: 20 metre
!=