POLYVAL Evaluate Polynomial Fit at Selected Points
Section: Optimization and Curve Fitting
Usage
Thepolyval
routine has the following syntax
y = polyval(p,x)
where p
is a vector of polynomial coefficients,
in decreasing degree (as generated by polyfit
, for example).
If x
is a matrix, the polynomial is evaluated in the matrix
sense (in which case x
must be square).
Function Internals
The polynomial is evaluated using a recursion method. If the polynomial is
then the calculation is performed as
Example
Here is a plot ofx^3
generated using polyval
--> p = [1 0 0 0] p = 1 0 0 0 --> x = linspace(-1,1); --> y = polyval(p,x); --> plot(x,y,'r-')
Here is the resulting plot