Hello,

i have some Problems with Matrix Inversion:

the Matrix is:

http://s7.directupload.net/file/d/2864/2qiobdfh_jpg.htm

the Result doesnt fit to Mathcad result:
http://s14.directupload.net/file/d/2864/lsxr79tp_jpg.htm
http://s1.directupload.net/file/d/2864/r3enm3au_jpg.htm

Do you know that Problem? or did i use wrong Syntax?

Thanks!

Adrian

Hello.

Could you please send a file with an initial matrix to me or to post it on forum?

Regards.

Hello!

here is it:
http://www.file-upload.net/download-4282811/Matrix-Problems.sm.html

The main Problem is at the end: the solution deosnt work!

Thanks for you help!

Adrian

Hello Adrian,

Just use the Numerical optimization for the last expression as well
[MATH=eng]gamma:B^{-1}*alfa[/MATH]
[MATH=eng]gamma=mat(0.059042586707757,0.109096474811639,0.142541413587456,0.154285714285714,0.142541413587457,0.109096474811639,0.059042586707757,7,1)[/MATH]

or use eval()
[MATH=eng]gamma:eval(B^{-1}*alfa)[/MATH]
[MATH=eng]gamma=mat(0.059042586707757,0.109096474811639,0.142541413587456,0.154285714285714,0.142541413587456,0.109096474811639,0.059042586707757,7,1)[/MATH]

In general, it is advisable to use Numerical optimization or eval() when matrix inversion is involved.

Regards,
Radovan

I want to ask you, if you find solution of the problem with inversion of the matrix, I have the same problem. From definition A*A^{-1}≡E and E have diagonal elements equal to one and other elements are equal to zero. But if I try A*A^{-1} in SMath, result is not identity matrix.