Symbolic result too large to display for a system of equation

[amohammadi]

Hello,

I am new to MathCad (version 15.0). I found similar issue in other posts but I was not able to implement it. I want to solve a system of equation for 4 equations and 4 variables. I receive the error "The symbolic result is too large to display". I need the symbolic result, because I am trying to find a general formula for any number of equations and variables for a specific problem .I'd appreciate it if you could help me with this issue.

I have attached the relevant file.

Thanks.

Abed.

[Werner_E · Accepted solution]

Symbolics can be quite beasty in Mathcad and usually there is not much you can do against that "result is to large ..." message.

But sometimes it helps to do what Mathcad suggests - assigning the expression to a variable.

In your case the result should be a 1 x 4 matrix and we could try to show each value separately - maybe a single value is not too large to display.

But in your case this fails. Digging further shows that the result is not a 1 x 4 matrix. Possibly Mathcads symbolics would show some if statements.

Fortunately the reason for this behaviour can be found. You had typed "2." instead of just "2" two times (2nd and third equation). Deleting the decimal points (which forces the symbolics into float mode) makes the whole thing work (don't ask me why 😉

Not sure if you will be really happy with the three page wide expressions you see, but here you are.

BTW, you used vector indices - guess it would be better to use literal indices (p.2 instead of p[2).

[amohammadi]

Thank you so much. I didn't expect such fast response! I couldn't do it without your help.

[LucMeekes]

And the solution to the general case is here:

Success!
Luc

[amohammadi]

Thank you for your reply. By general case I mean n equation and n variable with similar shape in a compact form. e.g. for 5 equation and 5 variable it looks like this:

Which again I can not get the value for each p due to large size of the equation.

[LucMeekes]

Here you go:

[LucMeekes]

And if that isn't general enough for you, have a look at this.

For N=3:

Now you have three functions that you can just plug the (vectors!) gamma, b and s in to get the results for the three p values.

If I change N=6:

Likewise, 6 functions for the six p- values, in terms of gamma, b and s.

Mathcad 11 file attached.

There's just one tiny little caveat....You need Mathcad 11 to successfully run this.

Success!
Luc

[amohammadi]

Thanks a lot! It seems that Mathcad 11 is not available to install, and I can not see the whole formula in the picture. Could you attach the result for n=5 and n=6 in a word file?

[LucMeekes]

The result for n=5 is in the file

                  LM_20181114_Solve5.mcd

attached to the other post (one higher).

Note that the expressions are very very large. It's not useful to put them in a word file.

I expect the result expressions for n=6 are even larger.

They are, and attached here, with proof.

Luc