DADiSP Worksheet Functions > Function Categories > Curve Fitting > POWFIT
Fits y(x) = A xb using linearization.
POWFIT(series)
(fit, coef) = POWFIT(series)
(fit, A, b) = POWFIT(series)
series |
- |
Input series or array. |
A series.
(fit, coef) = POWFIT(series) returns both the fit and the coefficients as a series.
(fit, A, b) = POWFIT(series) returns both the fit as a series and the coefficients as separate coefficients.
W1: 10 * (1..100)^0.5
W2: powfit(w1);overp(w1, lred)
overplots the original data with the calculated power fit.
(fit, coef) = powfit(w1)
fit is the same series as in W2
coef == {10.0, 0.5}.
POWFIT fits a power curve of the form:
The fit is accomplished by fitting a line to the following equation:
If x or y are not positive, the result will be complex.
The fitted power curve (fit, coef) = powfit(series) returns both the fit and the coefficients as a series where coef is in the form {A, b}.
The fitted power curve (fit, A, b) = powfit(series) returns the fit as a series and the coefficients as separate scalars.