Project - Data Handling and Interpolation
clear;
clc;
% interpolation of voltage and current data
% reading excel file data
D =readmatrix('VI.xlsx');
v=D(:,1); % voltage data seperating
i=D(:,2); % current data separating
xq=[-17,3:0.1:0.9]; % given interpolation
yq1=interp1(v,i,xq); % linear interpolation
yq2=interp1(v,i,xq,'spline'); % spline interpolation
% linear interpolation plotting
figure(1)
plot(v,i,'s',xq,yq1,':.');
title('linear interepolation')
xlabel('voltage (V)');
ylabel('current (I)');
legend('Actual value','interpolated value', 'location','northeast');
grid on;
% spline interpolation plotting
figure(2)
plot(v,i,'s',xq,yq2,'b: .');
title('SPLINE INTERPOLATION');
xlabel('voltage (V)');
ylabel('current (I)');
legend('Actual value','interpolated value','location','northeast');
grid on;
% saving the interpolation data into text file
% opening text file
vol_cu=fopen('VI._output.txt','w');
fprintf(vol_cu,' volatge current\n');
%writing voltage & current valve
fprintf(vol_cu,'%4.3f %5.3f\n',xq,yq2);
% saving linear interpolation graph
savefig(1,'vilinear.fig');
% saving spline interpolation graph
savefig(2,'vispline.fig');
fclose(vol_cu);
