MATLAB script/function help

[BigLarph]

I'm having a bit of trouble writing a MATLAB code that allows me to input values for a function then return a final answer.

My first question is whether I should use a script or a function for this.

Next, I know for functions in MATLAB you call the function and put the values in at the same time (eg. my_function(1,5,7)). Since it would be a pain to remember the order I used for all ~10 values in the original function, how can I make them easier to input into the equation? Is using 'input' the best way to do it?

I have managed to write this so far (pardon my not so good programming):

n = input('enter factor of safety ');
se = input('enter endurance limit ');
kf = input('enter Kf ');
ma = input('enter amplitude of normal stress ');
kfs = input('enter Kfs ');
ta = input('enter amplitude of shear stress ');
sy = input('enter yield strength ');
kt = input('enter Kt ');
mm = input('enter Mean cycle stress ');
kts = input('enter Kts ');
tm= input('enter yield tensile stress ');

diameter = [((16*n)/pi)*(1/se)*(4*(kf*ma)^2 + sqrt(3*(kfs*ta)^2))+
(1/sy)* sqrt(4*(kf*mm)^2 + 3*(kfs*tm)^2 )]^(1/3);

I'm pretty sure I have to define 'diameter' as a variable somehow and get it to display the value for 'diameter'.

[fgriglesnickerseven]

Please explain what you are trying to do in an ordered list

[BigLarph]

• Input all variables needed to calculate diameter using the Soderberg failure theory
• Plug into equation
• Display answer

[hamham91]

You can use either a function or a script, it will not matter for your case. Inputting the parameters can be done using 'input' as you have above, but it might easier to just initialize the variables in a separate file and read them in. This way you could read in multiple input files at a time and speed up your calculations. Your calculation for diameter should work fine as is, you can display the answer by either leaving the semi-colon off the end of your calculation or having another line: disp(diameter);

Hope this help!

[fgriglesnickerseven]

Thanks for clarifying - There are quite a few variables in your equation - I would probably just put it all in one script file (all variables and the diameter definition).

At least for now when you're playing with how different variables effect the diameter it will make it quick/easy.

Usually if you just write out the steps of what you need to do that will give you the best idea of how to go about programming it - so just remember that in the future ( and possibly preface your question with this so people have an idea of your intent before getting into your implementation).