### 18.11.1. General Usage Notes

The following are guidelines on how to set the various input arguments:

- The function call to `USER_STATEPT` must provide the input arguments in terms of thermodynamic properties and mixture composition, if applicable.

- User state point function calls do not support phases that use the "Saturation Temperature" or the "Small Droplet Temperature" heat transfer models.

- Each user state point function call must specify the material for which the output property is evaluated. The equation of state and constitutive relationship for the specified material are then used to evaluate the property.

- User state point function calls can accept an arbitrary number of single valued input arguments.

- Input arguments can be only thermodynamic properties and composition. Other variables are not supported.

- User state point function calls return a single valued result from the specified input arguments. The requested result must be a material property that is not one of the input arguments.

- In a simulation that involves disconnected domains, the specification of unique fluid names is required. Otherwise, the CFX-Solver may not be able to identify the corresponding materials.

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