Question

4. The excel file attached to this homework titled "question4.xlsx" contains data from a certain experiment. Column 1 shows the experimental value and column 2 shows the expected value. a. Open this file in Matlab and plot a graph for the expected value and the experimental value over the length of the file. (Y axis would be values and X axis would be length) b. Specify the line color and styles: red dashed line for experimental data & red solid line for expected calues. c. Include axis labels and a descriptive title (for example: Experimental val and Expected val d. Include a legend

Using MatLab what would be the script for problem 4 given that question4.xlsx is the chart in the second picture. I know how to upload it and find the length but when I try to do the graph no graph is showing up after I run the script.

Answer 1

% Matlab script to read an excel file and plot the graph of the values read
% read the data from the first worksheet in the Microsoft
% Excel spreadsheet file named "question4.xlsx" and returns the numeric data in array values.
[values,txt,raw] = xlsread('question4.xlsx');

% plots the experimental data
plot((1:1:size(values,1)),values(:,1),'r--');
hold on; % holds the current graph so that the subsequent plots can be plotted in the same graph
% plots the expected value
plot((1:1:size(values,1)),values(:,2),'r-');
hold off; % releases the current graph
% set the title
title('Experimental Values and Expected Values');
% set the x and y labels
xlabel('Record No');
ylabel('Values');
% set the legend
legend('Experimental','Expected');
%end of script

Output:

Experimental Values and Expected Values 85 Experimental Expected 80 75 70 65 55 50 45 40 1 2 3 4 7 8 Record No Values 60