Project - Data Handling and Interpolation

clear all

clc

DATA=xlsread("VI.xlsx"); %reading excel sheet using xlsread.

V=DATA(:,1); %fetching voltage data from column 1 from excel sheet

I=DATA(:,2); %fetching current data from column 1 from excel sheet

R=-17.3:0.1:0.9; %range for interpolation

VIR1=interp1(V,I,R); %linear interpolation syntax.

VIR2=interp1(V,I,R,'spline'); % spline interpolation syntax.

figure(1)

plot(I,V,'o',R,VIR1,':.') %plot for linear interpolation.

grid;

title('Linear Interpolation')

xlabel('Voltage (V)');

ylabel('Current (I)');

figure(2)

plot(V,I,'s',R,VIR2,'b: .');

title('Spline Interpolation'); %plot for spline interpolation.

xlabel('Voltage (V)');

ylabel('Current (I)');

A=fopen('VI_output.txt','w'); %saving interpolated data in text A.

fprintf(A,' Voltage Currentn');

fprintf(A,'%4.3f %5.3fn',R,VIR1); %writing voltage and current value.

savefig(1,'linear.fig'); %saving graph for linear interpolation

savefig(2,'spline.fig'); %saving graph for spline interpolation