[matlab]
计算归一化极向磁通
function x = calculateNormalizedPsi(gridfile)
    
    
    
    
    
    [varname, gridvalue] = readgridnc(gridfile);
    
    
    psixy = gridvalue{strcmp(varname, 'psixy')};
    psi_axis = gridvalue{strcmp(varname, 'psi_axis')};
    psi_bndry = gridvalue{strcmp(varname, 'psi_bndry')};
    
    
    x = (psixy(:,1) - psi_axis) / (psi_bndry - psi_axis);
end

function rho = calculateNormalizedr(gridfile)
    [varname, gridvalue] = readgridnc(gridfile);
    ShiftAngle = gridvalue{strcmp(varname, 'ShiftAngle')};
    q = abs(ShiftAngle/2/pi);
    Rxy = gridvalue{strcmp(varname, 'Rxy')};
    [~, col_index] = max(max(Rxy));
    R0=(max(max(Rxy))+min(min(Rxy)))/2;
    a=max(max(Rxy))-R0;
    r=Rxy(:,col_index)-R0;
    rho=r/a;
end