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FunctionQDepends

Description

This fitting function is the base class for all fitting functions that have:

• A range of energy transfers as their one-dimensional domain from which to take values

• The magnitude of the momemtum transfer, \(Q\), as one of their attributes.

Fitting functions for QENS data depending on \(Q\) should derive from this class.

There are two ways to update attribute \(Q\) in the fit function:

• The user inputs a particular value.

• The spectrum contains \(Q\) in addition to the range of energy transfers.

Conflict may arise when both options are available. In that case, priority is given to the \(Q\)-value contained in the spectrum. Here are some user cases:

• User cannot override the value of attribute \(Q\) if the spectrum contains a \(Q\)-value.

• User can set or update the value of of attribute \(Q\) is the spectrum does not contain a \(Q\)-value.

• The value of attribute \(Q\) will be updated everytime we pass a new spectrum containing a \(Q\)-value.

• The value of attribute \(Q\) will be erased if we pass a new spectrum not containing a \(Q\)-value. In this case it is the responsibility of the user to set the appropriate value.