02-19-15, 01:26 AM | #31 | |
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It looks like you are handling the equation correctly, although I do believe that there is an exponentiation operator that is available to you.
Other than that, I must assume that you are using the floating point precision appropriate to this application. Multiple Polynomial Regression Analysis. Quote:
If the process you are trying to address, primarily functions in only part of that range, I can recalculate, for maximum fit over that specified range, which will give you much greater accuracy within that specified range but would be a less accurate fit in the rest of the range (that you will not use). BTW, I replicated the equation I gave to you, on a high-quality spreadsheet, without Arduino limitations, and got the very same results, when rounded. You did good. Best, -AC P.S.: if your input pressure variable was called "psi", and your calculated output temperature variable was called "degF", then your one-line formula would be: Code:
degF=-40.3085122205+(1.81496452942*psi)+(-0.0101201804003*psi^2)+(3.05234258195e-005*psi^3)+(-3.37963005786e-008*psi^4) Good luck! %%%%%%%%%
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