Steinhart-Hart equation and a dataset

I have a set of 21 data points of tempurate(T) and resistance(R). I need to calculate the coefficients for the Steinhart-Hart equation:

Answer 1

[Rishabh Mishra]

Hi,

Based on your description of the issue, I would like to make some assumptions stated below:

• R = Column vector consisting resistance values
• T = Column vector consisting temperature values
• A,B,C = co-efficient of the equation

Use the code below:

p = polyfit( log(R) , 1./T , 4); 

p(4), p(3) & p(1) are the calculated values for A, B & C respectively.

Hope this helps.

[Wilmer Schroer]

This answer is false. The Steinhart-Hart equation has no 2nd degree polynominal. When you use polyfit, it will fit a curve with the first, second, third and fourth polynominal. The resulting fit is thus not the Steinhart-Hart fit but just a regular 4th degree polynominal fit.

When using polyfit, you should use polyfit(log( R ), 1./T, 3). This is because it calculates N+1 polynomials instead of N (so N has to be three).

[Wilmer Schroer]

I suggest you use the cftool add on and fit a custom function