Project :
In a laboratory experiment, data of voltage and current has been recorded and the same is attached in an excel file ( VI.xlsx ). Read the excel file in the Matlab program and perform the interpolation in the range of -17.3:0.1:0.9. Generate the interactive plot for the interpolated data. Additionally, compute the current values for given voltages below and store them in a text file.
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]’
SOL:clc % clear command window
clear all %clear workspace
file=xlsread('VI.xlsx')%read the excel file in the matlab using 'xlsread' matlab function.
V=file(:,1)
I=file(:,2)
x=[-17.3:0.1:0.9];
y=interp1(V,I,x,'spline');% Spline interpolation.
figure(1);
plot(V,I,'O',x,y,':.') %generate the interactive plot using matlab function 'plot'.
grid
title('voltage vs current')
xlabel('voltage')
ylabel('current')
%
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];
I2=interp1(V,I,VV) %compute the current values for voltge using matlab interpolation function 'interp1'.
M=[VV,I2]
fileID=fopen('VVI2.txt','w');%store all values in a text file.
fprintf(fileID,'%6s %12s\n','VV','I2');
fprintf(fileID,'%6.2f %12.8f\n',M);
fclose(fileID);
ANS:file =
-17.3000 -28.0000
-17.1000 -24.0000
-17.0000 -19.0000
-16.8000 -14.0000
-16.5000 -9.0000
-16.0000 -6.0000
-15.0000 -4.0000
-14.0000 -3.0000
-12.0000 -2.0000
-10.0000 -1.3000
-8.0000 -1.0000
-5.0000 -0.6000
-2.0000 -0.3000
-0.2000 -0.1000
0.0900 0
0.1900 0
0.2700 0
0.3900 0.0100
0.4300 0.0300
0.5000 0.1700
0.5500 0.4200
0.6000 1.2300
0.6200 1.9900
0.6500 3.9100
V =
-17.3000
-17.1000
-17.0000
-16.8000
-16.5000
-16.0000
-15.0000
-14.0000
-12.0000
-10.0000
-8.0000
-5.0000
-2.0000
-0.2000
0.0900
0.1900
0.2700
0.3900
0.4300
0.5000
0.5500
0.6000
0.6200
0.6500
I =
-28.0000
-24.0000
-19.0000
-14.0000
-9.0000
-6.0000
-4.0000
-3.0000
-2.0000
-1.3000
-1.0000
-0.6000
-0.3000
-0.1000
0
0
0
0.0100
0.0300
0.1700
0.4200
1.2300
1.9900
3.9100
I2 =
Columns 1 through 12
-26.0000 -24.0000 -2.9000 -2.7500 -2.5000 -2.2500 -1.6500 -1.1500 -0.7013 -0.7333 -0.1889 0
Columns 13 through 15
0 0.1700 1.6100
M =
Columns 1 through 12
-17.2000 -17.1000 -13.8000 -13.5000 -13.0000 -12.5000 -11.0000 -9.0000 -5.7600 -6.0000 -1.0000 0.1100
Columns 13 through 24
0.2500 0.5000 0.6100 -26.0000 -24.0000 -2.9000 -2.7500 -2.5000 -2.2500 -1.6500 -1.1500 -0.7013
Columns 25 through 30
-0.7333 -0.1889 0 0 0.1700 1.6100