Problem with radians and degrees

I am implementing this code. And the result does not match at all. The result must be in radians and the result must be the following:

sigma (1) = -0.247

omega (1) = 0.966

sigma (2) = -0.494

omega (2) = 0 ~ very small number almost zero

sigma (3) = -0.247

omega (3) = -0.966

I found this on the calculator (in radians). But the program doesn’t match at all

% Chebshevy Poles
    clc
    clear
    
    n = 3; % filter order
    ripple = 1; % dB
    epsilon = sqrt(10^(0.1*ripple)-1)
    a = (1/n)*asinh(1/epsilon)
    
    
    for k = 1:1:n
    sigma(k) = -sinh(a)*sin(((2*k-1)/2*n)*pi);
    omega(k) = cosh(a)*cos(((2*k-1)/2*n)*pi);
    end

The value of this a is 0.476

Answer 1

[the cyclist]

You need parentheses around 2*n. Otherwise, MATLAB will divide by 2, then multiply by n.

% Chebshevy Poles
    clc
    clear
    
    n = 3; % filter order
    ripple = 1; % dB
    epsilon = sqrt(10^(0.1*ripple)-1);
    a = (1/n)*asinh(1/epsilon);
    
    
    for k = 1:1:n
    sigmak(k) = -sinh(a)*sin(((2*k-1)/(2*n))*pi);
    omegak(k) = cosh(a)*cos(((2*k-1)/(2*n))*pi);
    end
    
    disp(sigmak)

   -0.2471   -0.4942   -0.2471

    disp(omegak)

    0.9660    0.0000   -0.9660

[Luccas S.]

Thanks, I was thinking it was a problem with some MATLAB conversion.