# [Scilab-users] Problems with Scilab- Xcos simulations (Algebraic loop / Derivative block).

2 messages
 Dear all,I'm trying to do a simulation involving a system of ordinary differential equations. However, in working out the block diagram, I came across an algebraic loop problem.```To solve this problem, I made a new arrangement of the equations and then it was necessary to include a derivative block.Two new problems have appeared: 1) the initial value of the output signal does not match the value obtained by the initial value theorem and 2) the signal has a strong oscillation (probably due to high frequencies).Can anyone help me solve these issues? Attached, the. Thank you very much.  ```--Marcus Vinicius Pereira de Souza, D.Sc. (Eng.)Prof. do Ens. Bas. Tec. TecnológicoCEFET/RJ | Campus Valença-RJCel: +55 32 9 8436 9695 (TIM - Wapp)_______________________________________________ users mailing list [hidden email] http://lists.scilab.org/mailman/listinfo/users EDOs.pdf (46K) Download Attachment 5SLA_AtividadeXcos.zcos (8K) Download Attachment =?UTF-8?b?c2ltdWxhY2FvNVNMQS5zY2U=?= (2K) Download Attachment
 The system described in your EDOS.ps file can be written in implicit form, A*[dy1/dt; dy2/dt] = F(y1,y2) but here you have A =[1 -1; -2 2], i.e. A is singular. I am not sure that; at least under this form, your system is well-posed. S. Le 08/04/2019 à 22:13, Marcus Vinicius Pereira de Souza a écrit : Dear all, I'm trying to do a simulation involving a system of ordinary differential equations. However, in working out the block diagram, I came across an algebraic loop problem. ```To solve this problem, I made a new arrangement of the equations and then it was necessary to include a derivative block.Two new problems have appeared: 1) the initial value of the output signal does not match the value obtained by the initial value theorem and 2) the signal has a strong oscillation (probably due to high frequencies).Can anyone help me solve these issues? Attached, the. Thank you very much.   ``` ``` ``` -- Marcus Vinicius Pereira de Souza, D.Sc. (Eng.) Prof. do Ens. Bas. Tec. Tecnológico CEFET/RJ | Campus Valença-RJ Cel: +55 32 9 8436 9695 (TIM - Wapp) ```_______________________________________________ users mailing list [hidden email] https://antispam.utc.fr/proxy/1/c3RlcGhhbmUubW90dGVsZXRAdXRjLmZy/lists.scilab.org/mailman/listinfo/users ``` _______________________________________________ users mailing list [hidden email] http://lists.scilab.org/mailman/listinfo/users