anglealpha.m

function alpha = anglealpha(theta, phi)
% Ôóíêö³ÿ êóòà â³äõèëåííÿ â³ä íàäèðó

% alpha - êóò â³äõèëåííÿ òî÷êè â³ä îñ³ íàäèðó
% theta - ïðîåêö³ÿ êóòà â³äõèëåííÿ íà ïëîùèíó âçäîâæ ïîëüîòó
% phi - ïðîåêö³ÿ êóòà â³äõèëåííÿ íà ïëîùèíó ïîïåðåê ïîëüîòó
% Âñ³ êóòè â ðàä³àíàõ

% âèáèòè ïîìèëêó ÷åðåç íåñê³í÷åíí³ñòü ïðè êóò³ â 90°
% alpha = atan(sqrt(tan(theta) .^ 2 + tan(phi) .^ 2));

% Äîäàòêîâ³ âàð³àíòè ðîçðàõóíêó
% theta2 = atan(tan(phi) .* cos(theta));
% phi2 = atan(tan(theta) .* cos(phi));

% alpha = acos(cos(theta) .* cos(theta2));
% alpha = acos(cos(phi) .* cos(phi2));
% alpha = asin(sqrt(sin(theta2) .^ 2 + sin(phi2) .^ 2));

% Òîìó óòî÷íèìî àëãîðèòì
if abs(phi) == (pi / 2)
    % ßêùî êóò phi = 90°, òî
    phi2 = atan(tan(theta) .* cos(phi));
    alpha = acos(cos(phi) .* cos(phi2));
elseif abs(theta) == (pi / 2)
    % ßêùî êóò theta = 90°, òî
    theta2 = atan(tan(phi) .* cos(theta));
    alpha = acos(cos(theta) .* cos(theta2));
elseif (abs(phi) ==(pi / 2)) && (abs(theta) == (pi / 2))
    alpha = pi / 2;
else
    alpha = atan(sqrt(tan(theta) .^ 2 + tan(phi) .^ 2));
end

end