Change Width of line

I want to change width of line that is passing from 80%capacity retention . I am attaching image and code below

clc

%crate=0:1:10;

G=-I_BT;

h=3700;%no. of cycles

T=30+273;%temp in kelvin

R=8.314;%universal gas const

capa=5.2;%battery capacity

%batt_curr batt_HESS=[1,2,3,4]

A=[G];

[n, xout] = hist(A,60);

c_rate=abs((xout.*(n>0))/capa);

B = exp(1.226*exp(-0.2797*c_rate)+9.263);

A_h=abs(xout.*(n>0)).*(n/3600);

Dk=zeros(h,2);

for i=1:h

q_k=B.*exp((-31700+370.3.*c_rate)/(R.*T)).*((i.*A_h).^0.55);

Qk=100-sum(q_k);

Dk(i,:)=Qk;

end

figure(3)

a=yline(80)

plot(Dk,'LineWidth', 4)

%set(gca,'fontsize', 18);

%set(gca,'LineWidth', 4);

ylim([0 100]);

a=yline(80)

xlabel('No. of Cycles');

ylabel('Capacity Retention %');

%legend('Battery Capacity Retention');

Answer 1

[Image Analyst]

yline(80, 'LineWidth', 3);

[Rajat Powade]

Can u please help me to find intersection of this two curves . Means please provide the code

Answer 2

[Star Strider]

The ‘I_BT’ value is missing.

cycnr80 = interp1(Dk,(1:numel(Dk)),80)

This should produce the cycle number where ‘Dk’ crosses 80 (assuming that the cycle number begins at 1).

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