An elevation is different. It shows the face of something, or perhaps more correct, the projection of an object/s to a plane. But my testing suggests it produces SECTIONS, not elevations.
Yes, you can use abbreviations in tables and figures. All abbreviations used in tables and figures should be defined in the table note or figure caption, respectively, even though the abbreviations will be also be defined in the text if they are used there.
In addition to f(x), other abbreviated symbols such as g(x) and P(x) are often used to represent functions of the independent variable x, especially when the nature of the function is unknown or unspecified. Common functions. Many widely used mathematical formulas are expressions of known functions.