Ok I am trying these but Mathcad is crashing on me
It used to give me a message that the solution is too big to display but not any more
http://communities.ptc.com/message/182372#182372
Is there a way I can store the symbolic calculation into an array as in:
http://communities.ptc.com/message/182371#182371
without calculating it then finding the elements one by one as LucMeekes did
Chad G. wrote:
Ok I am trying these but Mathcad is crashing on me
It used to give me a message that the solution is too big to display but not any more
It still works ok for me, giving the "too big to display" message, but not crashing. Have you made any changes?
Is there a way I can store the symbolic calculation into an array as in:
The only way I can think of is to copy each individual element and paste into a 4x1 vector.
Alan
I mean store elements directly without the "too big to display" since I do not need that whole answer
which I do not know why it crashes the computer I have not done changes
Ok I am trying these but Mathcad is crashing on me It used to give me a message that the solution is too big to display but not any more
Try repairing your Mathcad installation.
Is there a way I can store the symbolic calculation into an array as in:
http://communities.ptc.com/message/182371#182371
without calculating it then finding the elements one by one as LucMeekes did
Maybe I misunderstand what you are asking for, but if you have not calculated it then there is nothing to store.
here is the crash message
Problem signature:
Problem Event Name: APPCRASH
Application Name: mathcad.exe
Application Version: 14.0.0.163
Application Timestamp: 45ba2610
Fault Module Name: KERNELBASE.dll
Fault Module Version: 6.1.7601.17651
Fault Module Timestamp: 4e211319
Exception Code: e053534f
Exception Offset: 0000b9bc
OS Version: 6.1.7601.2.1.0.768.3
Locale ID: 1033
Sorry, the crash message means no more to me than it does to you.
As far as the worksheet goes, what you are trying to do will not work. When Mathcad sees a numeric assignment the first thing it does is check that all the variables on the RHS are defined. If that's not the case then the assignment is ignored and you get an error. So when Var is passed to the symbolic processor, there is no connection between it and the variable names in the vector. It simply tries to solve for "Var", and of course can't.
I am simply redoing what LucMeekes did (he did it in an older version of mathcad)
http://communities.ptc.com/message/182371#182371
If you say I cannot do this maybe that's why mathcad is crashing
I am simply redoing what LucMeekes did (he did it in an older version of mathcad)
Luc has version 11. The compute engine was rewritten going from version 11 to version 12, so what works in MC11 does not necessarily work in later versions. If you remove the numeric assignment (i.e. Sols:=), which is not allowed in MC11, yes, your worksheet works (I just tried it). But it will not work in version 12 or later.
If you say I cannot do this maybe that's why mathcad is crashing
Exactly which version are you running (including service releases)?
I am running Mathcad 14.0.0.163, any other way to overcome this. I am just trying to write the equations in the form
Chad G. wrote:
I am running Mathcad 14.0.0.163,
Download and install the latest service release you can get (probably M020)
I am just trying to write the equations in the form
Sorry, but that is not clear. Do you mean the form shown in Wayne's post?
Sorry for the confusion. I mean writing the following equations in the form
Thanks Alan, I do not understand the M matrix in your file (how did you find it? I am actually looking for it). I am trying to find the M matrix as in the following
whether it is the multiplication of two other matrices. All I am trying is to isolate Var in one side of the equation and Var0
Chad G. wrote:
Thanks Alan, I do not understand the M matrix in your file (how did you find it?
In each equation collect together the terms that multiply ur+, ur- etc. These form the conponents of the matrix M (as I did this rather quickly I might not have written them all down correctly - you should check). Because of the way your equations are written, this matrix multiplies both the vector of Var terms and that of the Var0 terms. This means your equations can be written in matrix form as M*Var-M*Var0 = V where V is the vector of terms a, b, c and d (you don't list a, b, c and d in your picture above, but they are in your original worksheet). This equation can be rewritten as Var = Var0 + inverseM*V.
Alan
Attached shows a systematic way of getting Mathcad to generate M automatically.
Alan
Thanks a lot and excellent, I understand what you are trying to do (in general) however I do not think the coefficients matrix for Var would be the same as Var0
To be more specific I did not understand the for loop
Chad G. wrote:
... I do not think the coefficients matrix for Var would be the same as Var0
You are right. It shows I should have been systematic in using Mathcad to generate the cofficients of both Var and Var0 instead of making the assumption they were the same!
To be more specific I did not understand the for loop
See attached , which contains a more detailed explanation of the for loop.
Alan
Edited: Sign corrected in attached file