polyfit (MathScript RT Module Function)
Owning Class: polynomials
Requires: MathScript RT Module
Syntax
[p, s] = polyfit(x, y, n)
[p, s, mu] = polyfit(x, y, n)
Description
Computes a polynomial of a specified degree that fits the input data using the least-squares method.
Inputs
| Name | Description |
|---|---|
| x | Specifies the x-coordinates of the data you want to fit. x is a vector. |
| y | Specifies the y-coordinates of the data you want to fit. y is a vector of the same length as x. |
| n | Specifies the degree of the polynomial you want to fit against x and y. n must be less than the length of x. n is a positive integer. |
Outputs
| Name | Description |
|---|---|
| p | Returns the coefficients in descending order of the polynomial fit. p is a vector. |
| s | Returns the Cholesky factor of the Vandermonde matrix. |
| mu | Returns the mean and standard deviation of x. LabVIEW uses these values to normalize x to improve the fit. mu is a vector. The first element of mu is the mean, and the second element of mu is the standard deviation. |
Examples
[P, S] = polyfit(1:10, rand(1, 10), 5)
[P, S, MU] = polyfit(1:10, [3, 3, 3, 4, 5, 6, 10, 12, 14, 15], 5)