POLYFIT can fit a polynomial of given ORDer to vectorial data, using as independent variable data index, rescaled between -1 and 1. Similarly, BIPFIT fits a bipolynomial of given orders (a matrix) to matrix data.
POLYVAL can calculate the VALues of a POLYnomial on an equidistant abscissa x, scaled between -1 and 1. Then only length(x) counts.
Similarly, BIPVAL calculates the VALues of BIPolynomial as a matrix of user defined size. For smoothing perpouses, same size can be used as original data matrix, parent to the BIPolynomial:
BIP = 3*4 matrix (bipolynomial up to Y^2, X^3)
Based on: POLYVAC
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