%該程序為vidic主程序
clear;%清除工作空間變量；
clc;format compact;format long g;
%per=[0:0.2:1.0 1.5:0.5:2 3:1:6];%設定自振周期范圍,分別采用不同的密度；
per=0.1:0.1:3;
sp=length(per);
nu=100;
Ru=2;
mag=0.4*9.81;
mvg=mag/0.6/9.81;
Tc=2*pi*2.0/2.5*mvg/mag;
To=zeros(1,2); 
To(1)=0.65*Tc*Ru^0.3;%%%初始值假定T>To,即 uc=Ru;
for i=1:sp
    T=per(i);
    if(T>To(1))
        uc(i)=Ru;        
    else%%%T<=To
        for j=1:nu
            tuc=(Ru-1)*To(1)/T+1;       
            To(2)=0.65*Tc*tuc^0.3;
            if(abs((To(2)-To(1))/To(1))<0.001)
                uc(i)=tuc;
            else
                To(1)=To(2);
            end
        end
    end 
end
figure(1)
plot(per,uc,'rd-.') %繪制出對應曲線圖；
grid on
xlabel('周期T(s)');
ylabel('延性系數u');
title('強度屈服系數至延性系數關系圖');
hold on

Ru=4;
To(1)=0.65*Tc*Ru^0.3;%%%初始值假定T>To,即 uc=Ru;
for i=1:sp
    T=per(i);
    if(T>To(1))
        uc(i)=Ru;        
    else%%%T<=To
        for j=1:nu
            tuc=(Ru-1)*To(1)/T+1;       
            To(2)=0.65*Tc*tuc^0.3;
            if(abs((To(2)-To(1))/To(1))<0.001)
                uc(i)=tuc;
            else
                To(1)=To(2);
            end
        end
    end 
end
figure(1)
plot(per,uc,'kd-.') %繪制出對應曲線圖；
hold on

Ru=6;
To(1)=0.65*Tc*Ru^0.3;%%%初始值假定T>To,即 uc=Ru;
for i=1:sp
    T=per(i);
    if(T>To(1))
        uc(i)=Ru;        
    else%%%T<=To
        for j=1:nu
            tuc=(Ru-1)*To(1)/T+1;       
            To(2)=0.65*Tc*tuc^0.3;
            if(abs((To(2)-To(1))/To(1))<0.001)
                uc(i)=tuc;
            else
                To(1)=To(2);
            end
        end
    end 
end
figure(1)
plot(per,uc,'kd-.') %繪制出對應曲線圖；
hold on

Ru=8;
To(1)=0.65*Tc*Ru^0.3;%%%初始值假定T>To,即 uc=Ru;
for i=1:sp
    T=per(i);
    if(T>To(1))
        uc(i)=Ru;        
    else%%%T<=To
        for j=1:nu
            tuc=(Ru-1)*To(1)/T+1;       
            To(2)=0.65*Tc*tuc^0.3;
            if(abs((To(2)-To(1))/To(1))<0.001)
                uc(i)=tuc;
            else
                To(1)=To(2);
            end
        end
    end 
end
figure(1)
plot(per,uc,'kd-.') %繪制出對應曲線圖；
hold on