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Mathcad prime 5.0

BB1
5-Regular Member
5-Regular Member

Mathcad prime 5.0

I wanted to create the Y BUS matrix from Netlist and solve that to get currents and voltages of each node.

 

For this i need to know how to solve the AX=B in matrix format, if all matrices(A,X and B) having variables only,

I want X in terms of Varibales(eqn)

 

Please check the 29th page of this pdf:

http://www3.imperial.ac.uk/pls/portallive/docs/1/7292571.PDF

ACCEPTED SOLUTION

Accepted Solutions
Werner_E
25-Diamond I
(To:BB1)

You may possibly be able to do what you are looking for, but as long as an expression contains an unknown/undefined variable you obviously can't evaluate that expression or function numerically (that means using the normal =).

View solution in original post

13 REPLIES 13

Hi,

 

you just use:-

 

 

Regards

Terry

Hi,

 

I will try this post again to get the graphic:

 

You just use:-

 

Capture.JPG

 

Cheers

Terry

BB1
5-Regular Member
5-Regular Member
(To:terryhendicott)

Please check the attachment, that one i am not able to solve

Hi,

 

The inverse of a matrix times the matrix is the identity matrix (all zeros except diagonals being one)

Capture.JPG

Cheers Terry

BB1
5-Regular Member
5-Regular Member
(To:terryhendicott)

Please check attachment.

 

why the same inverse is not working in program?, but outside its working fine, 

Hi,

 

Symbolic outside of the program does not need x and y to be defined to work.

Numeric inside the program needs x and y defined as numerical values to calculate the inverse.

 

Cheers

Terry

Werner_E
25-Diamond I
(To:BB1)


@BB1 wrote:

Please check attachment.

 

why the same inverse is not working in program?, but outside its working fine, 


It will work OK inside a program. too, but only if you evaluate the program symbolically, not numerically.

See here: https://community.ptc.com/t5/PTC-Mathcad/Mathcad-prime-5-0-matrix-multiplication/m-p/585721/highlight/true#M183830

Werner_E
25-Diamond I
(To:BB1)

Do you really need a general symbolic solution? It looks a bit uncomfortable:

B1.PNG

Wouldn't do a numerical solution do the job good enough?

You may either use the matrix approach or a solve block with the original node equations.

B2.PNG

BB1
5-Regular Member
5-Regular Member
(To:Werner_E)

I need the solution in symbolically..means interms of variables like in X,y
BB1
5-Regular Member
5-Regular Member
(To:Werner_E)

Thanks for your answer, please check the attachment.

 

The first two are giving properly and last one is not solving, am i missing anything or it cant solve??.

 

I need the answer for last one in program, Nett(FF).

 

Thanks In advance.

Werner_E
25-Diamond I
(To:BB1)

Always post the worksheet, not just pictures!

 

Why don't you just define Nett(B):=B^-1

Guess you don't need a global definition

 

Then you could use Nett(FF)->

As long as FF contains unknown variables you cannot evaluate your function Nett numerically.

BB1
5-Regular Member
5-Regular Member
(To:Werner_E)

As you said I can do, but the thing is my matrix will have only variable
and need to get some required data from that matrix using programming,
after that I need to form one matrix out of the main matrix, that matrix
also in variables only and finally need to do inverse of the matrix which I
formed from the main Matrix.

Everything it should solve symbolically,

Thanks for your patience...
Werner_E
25-Diamond I
(To:BB1)

You may possibly be able to do what you are looking for, but as long as an expression contains an unknown/undefined variable you obviously can't evaluate that expression or function numerically (that means using the normal =).

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