Problem with code-beginner

I have this code, and I receive the following error:

Index in position 1 exceeds array bounds (must not exceed 1).

Error in antennas3sector_final (line 21)

distances(site,r,c) = sqrt((x(r,c,site)+xshift(site)).^2+(y(r,c,site)+yshift(site)).^2);

Can you please help me ? Thank you.

distances = zeros(length(xx),length(yy),NumberOfSites);
for site = 1:NumberOfSites
    for r = 1:length(distances)
        for c = 1:length(distances)
            xshift(site) = isd*sind(AngleDistance*(site-1));
            yshift(site) = isd*cosd(AngleDistance*(site-1));
            distances(site,r,c) = sqrt((x(r,c,site)+xshift(site)).^2+(y(r,c,site)+yshift(site)).^2);
            
        end;
    end;
end;

[dpb]

for site = 1:NumberOfSites
    for r = 1:length(distances)
        for c = 1:length(distances)
            xshift(site) = isd*sind(AngleDistance*(site-1));
            ...

What is (site-1) when site==1 the first pass thru the loop???

Answer 1

[David Hill]

distances = zeros(length(xx),length(yy),NumberOfSites);
xshift = isd*sind(AngleDistance*((1:NumberOfSites)-1));%assume isd and AngleDistance is a constant
yshift = isd*cosd(AngleDistance*((1:NumberOfSites)-1));%calculate outside loop
for site = 1:NumberOfSites
    distances(:,:,site) = sqrt((x(:,:,site)+xshift(site)).^2+(y(:,:,site)+yshift(site)).^2);
end