What is gastroparesis? Gastroparesis, also called delayed gastric emptying, is a disorder that slows or stops the movement of food from the stomach to the small intestine. Normally, the muscles of the stomach, which are controlled by the vagus nerve, contract to break up food and move it through the gastrointestinal (GI) tract.
A variable is any factor, trait, or condition that can exist in differing amounts or types. An experiment usually has three kinds of variables: independent, dependent, and controlled. The independent variable is the one that is changed by the scientist. To ensure a fair test, a good experiment has only one independent variable. As the scientist changes the independent variable, he or she observes what happens. The scientist focuses his or her observations on the dependent variable to see how it responds to the change made to the independent variable.
As long as the context is clear, any placement is valid. Note however that it is a convention to put the independent variable on the horizontal axis, and the dependent on the vertical. Any departure from this should be explicitly noted for clarity. You could even call the independent variable f, and note the function x is you want, and graph the function x(f)... it's just a notation, but you can see how thing could be played with, and how it could be made as obscure as one wishes... if that is what you want! :).