Answer:
plot(VVolt,ImAmp,'-ob','MarkerFaceColor','r','linewidth',3);
VV = interp1(VVolt,ImAmp)
VVolt=-17.3:0.1:0.9;
xlabel('voltage');
ylabel('current');



fileid1=fopen('D:\MATLAB PROJECTS\week3\VI.xlsx','r')
fileid=fopen('C:\Users\rubyr\Desktop\mat_project.txt','w')
VV =[-17.2 -17.1 -13.8 -13.5 -13.0 -12.5 -11 -9 -5.76 -6 -1 0.11 0.25 0.5 0.61 ];
VVolt=-17.3:0.1:0.9;
c=interp1(VV,VVolt);
fprintf(fileid,'%d',VV)
figure
plot((-28:-14),VV,'o',VVolt,c,'*');
ylabel('voltage');
xlabel('current');
legend('VV','c');


