A polynomial is an expression that is made up of variables, constants, and exponents, that are combined using mathematical operations such as addition, subtraction, multiplication, and division (No division operation by a variable). Polynomials in MATLAB are represented as row of a vector containing coefficients ordered by descending powers.
For example, the equation G(x) = 2x4 + 3x3 – 4x + 1 could be represented as gfg = [2 3 -4 1]. For evaluating Polynomials we use function polyval( ), It evaluates the polynomial gfg at each point in x.
Example 1:
% MATLAB code for example: % to evaluate our polynomial gfg = % 2x4 + 3x3 - 4x + 1, at x = 4, gfg = [2 3 0 -4 1]; GFG= polyval(gfg,4) |
Output:
Example 2:
% MATLAB code for evaluating a polynomial with % matrices as variables, we use polyvalm( ) function. gfg = [2 3 0 -4 1]; X = [1 2 -3 4; 2 -5 6 3; 3 1 0 2; 5 -7 3 8]; GFG= polyvalm(gfg, X) |
Output:
Example 3:
% MATLAB code for finding roots % of polynomial : gfg= 2x4 + 3x3 - 4x + 1, gfg = [2 3 0 -4 1]; GFG = roots(gfg) |
Output: