public FunctionEvaluator setMissingValue(double value) {
        return setMissingValue(Tensor.Builder.of(TensorType.empty).cell(value).build());
    }
Sets the default value to use for variables which are not bound

@param value the default value
@return this for chaining
model-evaluation/src/main/java/ai/vespa/models/evaluation/FunctionEvaluator.java