A calorie is a measure of energy, specifically a calorie is the amount of energy taken to raise 1 cl of water by 1 degree (centigrade).
a carbohydrate is a refined source of energy, so ogically yes there is a very clear relation, (more energy = more calories, (since a calorie is a measure of energy)...
As for the relationship.
(go to google type calories carbohydrates, press I'm feeling lucky!)
there is 4 calories in each gram of carbohydrates, regardless of whether the carbohydrate source is simple of complex.