How to solve linear equation systems in Java? [on hold]

June 13, 2019, at 4:10 PM

I am developing a solver for truss systems (for mechanical and civil engineers). In this software, I need a linear equation solver.

Below linear equation system (K*X=F) is little different than equation systems that we know. In classical eqaution systems, all of the elements of X matrice are unknown and all of the elements of F matrice are known. However, in my case, some elements of X matrice (x3 and x4) are unknown and some of them are known (12 and 0). This is also valid for F matrice too. Are there any code written in Java libraries or developed by you for this situation?

     ( K        *     X     =    F )
| 1  2  3  42|      | 12 |     | F1 |
| 65 26 35 98|  *   |  0 |  =  | F2 |
| 13 35 95 65|      | x3 |     |  0 |
| 12 65 98 99|      | x4 |     |  0 |
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