Sensitivity Analysis in Mathcad 14

[ptc-4537713]

Hello all,

I am beginner in mathcad 14 and right now i'am working in sensitivity analysis of Steel Catenary Riser. I have a lot of equations with summary at the end. The problem is I want to change constants that I define in beginning of worksheet many time to analyze its sensitivity. Can I use loop or global definition for this ?

[Fred_Kohlhepp]

Global definitions work well for this if you're playing "What if" games.

[ptc-4537713]

Well, I playing plenty of what if games. For each constant I want to change it 10 to 100 times to analyze its sensitivity to the result. The change is incrimental so can I use programming in mathcad to do it?. Changing global definition for at least 50 times seem realy tiring for me.

[VladimirN]

Hello!

Can you attach your worksheet to the message?

[ptc-4537713]

Ah yes, I forgot to attach it.

Basically, I want to change the constants in Design Basis, 4 in total (Outer Diameter, SG, Water Depth, Internal Pressure),multiple times to see which influence wall thickness greatly. The file I attach only a fraction of calculation I do so I looking for loop to make it easier.

[wayne]

Suggest writing as functions, something like the attached

[ptc-4537713]

I see, thank you for your suggestions and thought in my work, I really appreciate it.

I also thinking about using function to all equations that have contants I want to change. Then, is this the only way ?

My principle in learning programming is always search for the most efficient way to get result, so I just curious.

[wayne]

Generally, I believe that most would use functions. When done individually, the work sheet is easy to debug. You can include these functions in programs to do more at one time if you like, or pack all into one program if you really need to.

You can output different results from one program by collecting results into a nested matrix, and then parse that matrix. You will need to strip units, if results have different dimensions (units), and then put them back after parsing. However, I would suggest you get a working file first, then go back and increase efficiency.

[ptc-4537713]

Thank you, I think I will take that for now.

I have one more question, what is the use of " ` " in plot ? This is the first I see that

[wayne]

Just wanted to change the variable in the plot, becasuse h was previously defined. I used h` instead.