[Scilab-users] Consistency in linearization function
Hello people, I am not sure if I am doing something wrong but the lin function for linearization of a non-linear function surrounding a given point is returning different results each time I call it. And sometimes the results affects the following calculations I am performing (like root locus, for example). Below I pasted the output of a same linearization call. --> [A_body,B_body,C_body,D_body] = lin(sim_f16_body, X0_lin_body, U0); A_body A_body = -0.0209023 0.0519875 -32.146890.454861 -0.0403812 -1.0077261 -1.17722 456.03564 0. 0. 0. 1. 0.0002606 0.0026867 -0.0006798 -1.0747435 --> [A_body,B_body,C_body,D_body] = lin(sim_f16_body, X0_lin_body, U0); A_body A_body = -0.0201514 0.0538445 -32.144830.4545237 -0.0464131 -1.0221136 -1.1907031 456.02225 0. 0. 0. 1. 0.0004170.0020722 -0.0011822 -1.0745151 --> [A_body,B_body,C_body,D_body] = lin(sim_f16_body, X0_lin_body, U0); A_body A_body = -0.0195838 0.0528224 -32.148353 0.4557581 -0.0495045 -1.0029337 -1.1827851 456.02261 -1.970D-16 0. -1.203D-16 1. 0.567 0.0028515 -0.533 -1.0754311 --> [A_body,B_body,C_body,D_body] = lin(sim_f16_body, X0_lin_body, U0); A_body A_body = -0.0196784 0.0539473 -32.148072 0.4556623 -0.050291 -1.0081099 -1.1862481 456.02452 1.263D-16 0. 0. 1. 0.0002898 0.0026783 -0.0003306 -1.075333 Also, I made an overplot of a simulation using the linear and non-linear systems, as shown below (blue curve is the non-linear system and the green curves are linear system from several lin executions). [image: image.png] The full code is here [1]. Anyone faced something like that? I'd appreciate any help. [1] https://github.com/fsandre/mcflight/blob/master/scripts/controls/nz/sim_body_stab_comparison.sce -- André ___ users mailing list users@lists.scilab.org http://lists.scilab.org/mailman/listinfo/users
Re: [Scilab-users] Function "locate" for 3d graphs
Hi Iza, What if you use the linear_interpn [1]? [1] https://help.scilab.org/doc/5.3.3/en_US/linear_interpn.html Regards, André Em qui, 14 de jun de 2018 às 08:30, Izabela Wójcik-Grząba escreveu: > Hello, > > I've got another question. Is there a function like "locate" but > appropriate for param3d plot. I would like to pick some points from my > param3d plot. > > Regards, > Iza > ___ > users mailing list > users@lists.scilab.org > http://lists.scilab.org/mailman/listinfo/users > ___ users mailing list users@lists.scilab.org http://lists.scilab.org/mailman/listinfo/users
[Scilab-users] Xcos Scilab 6.0.1
Hello guys. I am building a model in Xcos (Scilab 6.0.1) and I am facing some problems that I am not sure if they are bugs or misuse from my side. * When a select a piece of the model and turn it to a superblock (right click -> selection to superblock), after playing the simulation I got a message error on console which says "invalid index". Then I realized that all the edges (lines) linking the blocks were like "doubled". Deleting all of them and redoing the links made it work well; * The block *Expression* from the pallette "user defined functions" requires that I create dummy variables u1, u2, u3, ... on my context of variables. I thought it would be unecessary. -- André Ferreira da Silva ___ users mailing list users@lists.scilab.org http://lists.scilab.org/mailman/listinfo/users
[Scilab-users] F-16 aircraft model
Hello, I recently translated the F-16 model (originally in Fortran) from Steven And Lewis book (Aircraft Control and Simulation). The code is available at GitHub [1]. I apologize for possible newbie mistakens that there might be there. I am not that expert in Scilab yet. I used this model to illustrate the (probably) most famous Non-Minimum-Phase Zero example of the Aeronautical Engineering, which is described here [2]. Maybe this model can be useful for others in the community. [1] https://github.com/fsandre/mcflight [2] http://e-feather.blogspot.com.br/2018/04/aircraft-diving-before-climbing-or-nmp.html Best regards, André Ferreira da Silva ___ users mailing list users@lists.scilab.org http://lists.scilab.org/mailman/listinfo/users