Is the computation of Beta correct ? Please could anyone correct the codes based on the equations ?

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My code for Beta along with the values :
function beta_n_values = Beta(n, d)
% Beta function to calculate Beta^n(k - d)
% n: Degree of the polynomial
% d: Interpolation point as a random variable with |d| < 0.5
% Calculate the lower and upper bounds of k
k0 = ceil(d - (n + 1) / 2);
k1 = floor(d + (n + 1) / 2);
% Define the range of k values
k_values = k0:k1;
% Pre-compute the coefficients a_p(k) for each k using the calculate_ap function
a_p_values = calculate_ap(n, d); % Make sure the calculate_ap function is defined
% Initialize an array to store the values of Beta^n(k - d)
beta_n_values = zeros(size(k_values));
% Loop over each k in k_values to compute Beta^n(k - d)
for k_idx = 1:length(k_values)
k = k_values(k_idx);
% Initialize the sum for this k
beta_n_k = 0;
% Loop over p from 0 to n
for p = 0:n
% Get the coefficient a_p(k) from the precomputed matrix a_p_values
a_p_k = a_p_values(p+1, k_idx); % MATLAB indexing starts from 1, so use p+1
% Add the term a_p(k) * d^p to the sum
beta_n_k = beta_n_k + a_p_k * d^p;
end
% Store the computed value of Beta^n(k - d)
beta_n_values(k_idx) = beta_n_k;
end
% Display the computed Beta^n(k - d) values
disp('Computed Beta^n(k - d) values:');
disp(beta_n_values);
end
% Input the degree of the polynomial
n = input('Enter the degree (n): '); % Example: n = 3;
% Generate a random interpolation point d with |d| < 0.5
num_points = 1;
d = -0.5 + (0.5 - (-0.5)) * rand(num_points, 1);
a_p_values = calculate_ap(n, d);
disp('The computed a_p^k values are:');
disp(a_p_values);
beta_n_values = Beta(n, d);
disp('Computed Beta^n(k - d) values:');
disp(beta_n_values);
The solution for a_p and beta is :
>> SplineCalculation
Enter the degree (n): 3
Calculated a_p(k) values:
0.6667 0.6667 0.6667 0.6667
-1.0000 -1.0000 -1.0000 -1.0000
0.5000 0.5000 0.5000 0.5000
0 0 0 0
Computed Beta^n(k - d) values:
0.3432 0.3432 0.3432 0.3432
The code for function a_p:
function a_p_values = calculate_ap(n, d)
% n: Degree of the polynomial
% d: Interpolation point as a random variable with |d| < 0.5
% Define the range for p (0 to n)
p_values = 0:n;
% Calculate the lower and upper bounds of k
k0 = ceil(d - (n + 1) / 2);
k1 = floor(d + (n + 1) / 2);
% Define the range for k
k_values = k0:k1;
% Initialize a matrix to store a_p(k) values
a_p_values = zeros(length(p_values), length(k_values));
% Loop through each value of p to compute a_p for each k
for p_idx = 1:length(p_values)
p = p_values(p_idx);
% Calculate the binomial coefficient (n choose p)
binomial_np = nchoosek(n, p);
% Calculate the factorial term 1/n!
n_factorial_term = 1 / factorial(n);
% Loop through each value of k
for k_idx = 1:length(k_values)
k = k_values(k_idx);
% Initialize the sum for this combination of p and k
sum_result = 0;
% Sum over m from 0 to n+1
for m = 0:n+1
% Calculate the binomial coefficient (n+1 choose m)
binomial_n1m = nchoosek(n+1, m);
% Calculate the term (-1)^m
sign_term = (-1)^m;
% Calculate the term (n+1)/2 - m
difference_term = (n+1) / 2 - m;
% Calculate the term (difference_term)^(n-p)
power_term = difference_term^(n - p);
% Calculate the Heaviside function mu(p - m + (n+1)/2)
mu_term = heaviside(p - m + (n+1)/2);
% Add the current term to the sum
sum_result = sum_result + binomial_n1m * sign_term * power_term * mu_term;
end
% Calculate a_p(k) for the current p and k
a_p_values(p_idx, k_idx) = n_factorial_term * binomial_np * sum_result;
end
end
% Display the calculated a_p(k) values
disp('Calculated a_p(k) values:');
disp(a_p_values);
end
Is the code correct cause all are convolutions basically
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