Functions > Data Analysis > Curve Fitting > Example: Thiele Interpolation and Regression
  
Example: Thiele Interpolation and Regression
Use the Thielecoeff and Thiele functions to fit a curve through a data set. The Thiele functions can be considered a regression technique since the Thiele coefficients are extracted.
1. Enter a set of measured data representing the saturation temperature of boiling water in °C.
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2. Use the Thiele method to interpolate a curve through the data set.
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3. Use the polynomial regression method to interpolate a curve through the data set.
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4. Plot the data set and the two interpolated curves.
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5. Compare the calculated results returned by the Thiele method to two mid-points from the steam tables.
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The calculated data points match the published data very closely.
6. Using the Thiele interpolated curve, calculate the temperature at which water boils in Mexico city 2250m above sea level.
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Reference
The International Association for the Properties of Water and Steam, http://www.iapws.org