Selecting values to make further calculations

Hi,

I am trying to complete the next step of my coding to design steel portal frames. For my next calculations I need to select a rafter section so I can do my stanchion calculations based on the resistance of my chosen rafter section. How can I select one of my displayed sections below and use the moment resistance as stated to continue my calcs.

Thanks

Lr = L/2 + h/tand(theta); % N is the distance from stanchion to base of reactant line where it meets the ground level

syms m
eqn = m^2/(2*w) + m*(5*Lr/3 - L/3) + w*L^2/8; % derived graphical method equation

M = solve(eqn,m); 
m1 = max(double(M)); 

Y = -(w/2)*(-m1/w).^2 + w*L^2/8; 
R = -(m1.^2/w) - m1.*Lr; 

Mr = Y - R; % Target rafter Mp

disp (table( Mr ))

% Values from Blue Book put into directory to suggest members

Name = ["254x102x28"; "254x146x31"; "254x146x37"; "254x146x43"; "305x102x25"; "305x102x28"; 
Resistance = [97.1; 108; 133; 156; 94.1; 111; 132; 148; 169; 196; 171; 198; 233; 149; 181;
crossSectionInfo = table( Name, Resistance );

crossSectionInfo = sortrows( crossSectionInfo, 'Resistance' );

bestCrossSectionIndex = find( crossSectionInfo.Resistance > Mr, 5, 'first'); % five sections with suitable Mp resistance

disp( crossSectionInfo(bestCrossSectionIndex,:) )

result = input('Which steel section would you like to select?:');

disp( 'Value is');
disp(crossSectionInfo.Resistance);

Answer 1

[Cris LaPierre]

There are a couple errors with the snippet of code included above, but I suspect that is becaue some code is missing. Assuming it runs without error when it is all there, I'd suggest a couple things.

1. use the str = input(prompt,'s') syntax. The 's' means a string input is expected. Read more here.
2. Once you capture the input, you need to do a comparison to find which item in Name it corresponds to.
3. Use the info from #2 to find the corresponding row in Resistance.

A stripped down version of how you could do this is below.

result = input('Which steel section would you like to select?:','s');
disp( 'Value is');
disp(crossSectionInfo.Resistance(Name==result));

[Finlay Brierton]

Thanks Chris, I will try and work on this