Project - Data Handling and Interpolation

x = xlsread('VI');
v = x(:,1); %% taking data from 1st col
i = x(:,2); %%taking data from 2nd col
a = -17.3:0.1:0.9; %%range . if no range then whole thing
b = interp1(v,i,a); %%direct interpolation command giving two input variables & interpolation range
%% ploting graph with data valuesand interpolated values
plot(v,i,'o--',a,b,'r*')
%%saving the file command
fileid = fopen('projectweekIII','w');
fprintf(fileid,'%f\n','projectweekIII');