User`s guide

Polynomial Evaluation

5-343

5Polynomial Evaluation

Purpose Evaluate a polynomial expression.

Library Math Functions / Polynomial Functions

Description The Polynomial Evaluation block applies a polynomial function to the real or

complex input at the

In port.

y = polyval(u) % Equivalent MATLAB code

The Polynomial Evaluation block performs these types of operation more

efficiently than the equivalent construction using Simulink Sum and Math

Function blocks.

When the

Use constant coefficients check box is selected, the polynomial

expression is specified by the

Constant coefficients parameter. When Use

constant coefficients

is not selected, a variable polynomial expression is

specified by the input to the

Coeffs port. In both cases, the polynomial is

specified as a vector of real or complex coefficients in order of descending

exponents.

The table below shows some examples of the block’s operation for various

coefficient vectors.

Each element of a vector or matrix input to the

In port is processed

independently, and the output size and frame status are the same as the input.

Coefficient Vector Equivalent Polynomial Expression

[12345]

[1 0 3 0 5]

[1 2+i 3 4-3i 5i]

4u 5++++=

5++=

2 i+()u

43i–()u 5i++++=