# not able to evaluate the value for an equation using the data from a table, table is three columns data

2 views (last 30 days)
kaixi gu on 10 Sep 2022
Edited: Seth Furman on 13 Sep 2022
%creat symbol for axial force, length, thickness, displacemnent and width
syms f l t d w
%define governing equations for parameter
stress = f./(t*w)
strain = d./l
%measurement resolution and uncertainty
%zeroth order uncertainty
%define symbolic data
f = T(:,2);
l = 6.125;
t = 0.057;
d = T(:,1);
w = 0.414;
%substitute value into equation
stress = eval(stress);
strain = eval(strain);
Pulkit on 13 Sep 2022
Try using 'readmatrix' function instead of 'readtable' as readtable outputs table object which is not supported by element wise operations. If problem still presist please share the exact error message you are getting and also type of data in Intro_specimen 2.txt

Seth Furman on 13 Sep 2022
Edited: Seth Furman on 13 Sep 2022
You just need to change the parentheses-() to curly braces-{} when pulling data of the table.
T = array2table(magic(3))
T = 3×3 table
Var1 Var2 Var3 ____ ____ ____ 8 1 6 3 5 7 4 9 2
%creat symbol for axial force, length, thickness, displacemnent and width
syms f l t d w
%define governing equations for parameter
stress = f./(t*w)
stress = strain = d./l
strain = %measurement resolution and uncertainty
%zeroth order uncertainty
%define symbolic data
f = T{:,2}; % <-- curly braces instead of parentheses
l = 6.125;
t = 0.057;
d = T{:,1}; % <-- curly braces instead of parentheses
w = 0.414;
%substitute value into equation
stress = eval(stress)
stress = 3×1
42.3765 211.8824 381.3883
strain = eval(strain)
strain = 3×1
1.3061 0.4898 0.6531

### Categories

Find more on Equation Solving in Help Center and File Exchange

R2022a

### Community Treasure Hunt

Find the treasures in MATLAB Central and discover how the community can help you!

Start Hunting!