clear all;
close all;
clc;

data = csvread('file.csv');

% Extract the first row as x points
x = data(1, :);

% Initialize the variable B as an empty matrix
B_t0 = [];

% Loop over rows
num_rows = size(data, 1);
num_columns = size(data, 2);

coeff = [];

% Desired polynomial degree
polynomial_degree = 20;  % Modify the polynomial degree according to your needs

% Define the symbolic variable 'x'
x_symbolic = sym('x');

% Loop to obtain polynomial coefficients and generate plots
for row = 2:num_rows
    % Extract the current row as values to interpolate (B)
    B_current = data(row, :);
    
    % Use polyfit to obtain polynomial coefficients
    coefficients = polyfit(x, B_current, polynomial_degree);
    
    % Convert coefficients into a symbolic object
    symbolic_polynomial = poly2sym(coefficients, x_symbolic);
    
    % Get the textual representation of the polynomial
    string_polynomial = char(symbolic_polynomial);
    
    % Display the polynomial representation
    disp(['Polynomial for row ', num2str(row), ': ', string_polynomial]);
    
    % Evaluate the polynomial at x points
    y_values = polyval(coefficients, x);
    
    % Plot the polynomial
    figure;
    plot(x, B_current, 'o', x, y_values, 'LineWidth', 2);
    title(['Polynomial for row ', num2str(row), ', degree ', num2str(polynomial_degree)]);
    xlabel('x');
    ylabel('Polynomial');
    legend('Original data', 'Interpolating polynomial', 'Location', 'Best');
    grid on;
end