functioninterpolate
Function for cubic hermite spline interpolation of table data
Extends from Modelica.Icons.Function (Icon for functions).
Information
This function returns the value on a cubic hermite spline through the given support points and provided spline derivatives at these points. The spline derivatives at the support points can be computed using Buildings.Utilities.Math.Functions.splineDerivatives. The support points must be monotonically increasing. Outside the provided support points, the function returns a linear extrapolation with the same slope as the cubic spline has at the respective support point.
A similar model is also used in the CONTAM software (Dols and Walton, 2015).
This function is used in Buildings.Airflow.Multizone.Table_m_flow and Buildings.Airflow.Multizone.Table_V_flow
References
- W. S. Dols and B. J. Polidoro,2015. CONTAM User Guide and Program Documentation Version 3.2, National Institute of Standards and Technology, NIST TN 1887, Sep. 2015. doi: 10.6028/NIST.TN.1887.
Inputs
| Type | Name | Default | Description |
|---|---|---|---|
| Real | u | Independent variable | |
| Real | xd | x-axis support points | |
| Real | yd | y-axis support points | |
| Real | d | Derivatives at the support points |
Outputs
| Type | Name | Default | Description |
|---|---|---|---|
| Real | z | Dependent variable with monotone interpolation |
Revisions
-
February 29, 2024, by Hongxiang Fu:
Moved to Buildings.Utilities.Math.Functions from Buildings.Airflow.Multizone.BaseClasses.
This is for IBPSA, #1844. -
February 26, 2024, by Hongxiang Fu:
Correct implementation to make it smooth.
This is for IBPSA, #1840. -
February 2, 2022, by Michael Wetter:
Revised implementation.
This is for IBPSA, #1436. -
Apr 6, 2021, by Klaas De Jonge:
First Implementation.