What are functions?
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- page.width
- frametag.height
- frametag.paragraphtag.centerX
Self
When using a formula in the location of a frame, you can use the tag of the frame, but you can also use "self".
E.g. self.height refers to the own height of the frame.
Below an example to align the frame to the bottom, by using a rather complex formula 
combined with a reference point at the top.
You can set the Y position, to the page height (would be bottom) minus the own (self) height.
Variables
It is possible to use variables in the calculation, but only variables of type number or coordinate. For now, only the value of the variable can be referenced. No other meta information.
"variable.value" or "variable" will both resolve to the actual value of the variable.
In case a variable has the same name as a frame tag, this property being used will indicate if the user intends to use the variable value or the frame property. (there is no "value" property on frames and no width, height, etc on a variable)
If page.property is used in a calculated value, it will always refer to the page in the document, never to a frame with tag "page".
Functions within the calculation
Following additional functions are available for application in the calculations
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