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The rating curves module is a standard file (i.e. it has a fixed name) which contains all the rating curves used in your system. A rating curve is referenced by the location id. I.e. each location has a specific rating curve for that point in the river. Furthermore a rating curve can have one or more periods for which it is valid. For each location there can be different rating curves that are valid for different times.
When a the transformation module needs to use a rating curve for a given location at a given time, then it will search all rating curves for the given location id. From all rating curves with the given location id, it will use the rating curve that is valid for the given time. For each location and each point in time there can be only one rating curve that is valid for that location and that time.
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