Save data from for loop into array

Hi,

I'm writing a piece of code to analyse some mechanical testing data. I am trying to save the data from the for loop into an array. However, I'm encountering an error each time. It reads an excel table, and then plots the force and extension through iterating through the spreadsheet. I am just can't figure out how to extract the maximum forces into an array. Here is the code.

clc
clear
close all
%% 5mm joints
figure()
A=readtable('Master-coupon-results-cleaned.xlsx','Sheet','5mm');
for i=0:3:(width(A)-1)
    Force=A{:,2+i};
    Stroke=A{:,3+i};
    MaxForces=max(A{:,2+i})
    Max(i)=MaxForces
plot(Stroke,Force) 
hold on
grid on
xlabel('Displacement (mm)')
ylabel('Force (N)')
title('Force vs displacement graph for 5mm lap joint')
end

[David Hill]

Attach your xlsx spreadsheet if you can.

[Christian Boaitey]

Here's the file

Answer 1

[Voss]

Max(i)=MaxForces gives an error when i == 0, because indexing starts at 1.

Furthermore, i goes 0, 3, 6, ..., and I imagine you want those values to go into elements 1, 2, 3, ... of Max, so some adjustment is necessary. See below:

clc
clear
close all
%% 5mm joints
figure()
A=readtable('Master-coupon-results-cleaned.xlsx','Sheet','5mm');
for i=0:3:(width(A)-1)
    Force=A{:,2+i};
    Stroke=A{:,3+i};
    MaxForces=max(A{:,2+i});
%     Max(i)=MaxForces
    Max(i/3+1)=MaxForces; % i==0 -> index 1, i==3 -> index 2, etc.
    plot(Stroke,Force) 
    hold on
    grid on
    xlabel('Displacement (mm)')
    ylabel('Force (N)')
    title('Force vs displacement graph for 5mm lap joint')
end

disp(Max);

   1.0e+03 *

    2.4656    3.0149    2.0699    2.1248    1.6334    2.0154    0.7336    2.4228    2.3124    2.0752