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No matter which method you are using, you should always check the result of your operations from time to time with the built-in preview methods (see → “ Simulation RetimeRetiming: Basics ”). Once you are satisfied, make your → “ Input/Output Settings ”, and press “Retime”.
Expressions
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Expressions can be very complex, and it is possible to combine mathematic functions (sine, cosine, square root, etc.), and perform calculations (addition, multiplication, etc). Under “Insert” you will find drop-down lists with the entire range of elements. Expressions are a fast and convenient method, but it can be difficult to create specific behaviour by combining functions like sine or cosine. In situations like that you should consider → drawing curves.
Another effect you can see with predefined functions is that the curve is increasing or decreasing, as shown in the sine curve below:
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