private Map<Reference, TensorType> featureTypes() {
        Map<Reference, TensorType> featureTypes = inputs().values().stream()
                .collect(Collectors.toMap(Input::name,
                                          input -> input.type().tensorType()));
        allFields().forEach(field -> addAttributeFeatureTypes(field, featureTypes));
        allImportedFields().forEach(field -> addAttributeFeatureTypes(field, featureTypes));
        return featureTypes;
    }
Creates a context containing the type information of all constants, attributes and query profiles
referable from this rank profile.
config-model/src/main/java/com/yahoo/schema/RankProfile.java