# Xcos model set error - scicos\_new: Wrong value for input argument #2: unable to set "model" **URL:** \ **Category:** Xcos\ **Created:** [April 16, 2024, 10:08pm UTC](https://scilab.discourse.group/t/xcos-model-set-error-scicos-new-wrong-value-for-input-argument-2-unable-to-set-model/469 "2024-04-16T22:08:12Z")\ **Posts on this page:** 1\ **Page:** 1
**Author:** ![Vimsrocz](https://avatars.discourse-cdn.com/v4/letter/v/ed8c4c/32.png) [@Vimsrocz](https://scilab.discourse.group/u/Vimsrocz)\ **Post date:** [April 16, 2024, 10:08pm UTC](https://scilab.discourse.group/t/xcos-model-set-error-scicos-new-wrong-value-for-input-argument-2-unable-to-set-model/469/1 "2024-04-16T22:08:13Z")
As per mention in the Xcos block setup [Block Parameters](https://help.scilab.org/scicos_model). There is requirement of two file for block in XCOS. Simulation file and Interface file. Model setup has error in the interface file and code is ```auto // Kalman_Filter_IF.sci // The interface file for the generic Kalman Filter block. // This block is externally activated to take measurements data. // Takes the continuous positions velocity or accelerations as input, adds some // errors (noise, scale, nonlinearity, misalignment) and gives // it as the output. // Abbrev. // IF: Inertial Frame, BF: Body Frame, // Model input: // 2x2 Real - State vector with position and velocity BF w.r.t. IF // 1 Real - Covariance vector // Model output: // 2x2 Real - Single axis gyro measurement output w.r.t. BF // 1x1 Real - Error flag // 0: No error // 1: Positive saturation error // 2: Negative saturation error // Model states: // 1x1 Real - Random walk error // Model parameters: // 2x2 Real - State Vector measurement unit vector w.r.t. BF (Unit vector) // 1x1 Real - Noise mean (bias) of the sensors // 1x1 Real - Noise stddev of the sensors // 1x1 Real - Scale error // 2x1 Real - Misalignment error // 1x1 Real - Random walk error function [x, y, typ] = Kalman_Filter_IF(job, arg1, arg2) funcprot(0); x = []; y = []; typ = []; getInputFromSim = 1; initial_state = [0.1; 0.0]; // 2*1 matrix initial_covariance = [1.0, 0.0; 0.0, 1.0]; // 2*2 matrix select job // Initialize with mask parameters if any case "plot" then standard_draw(arg1); case "getinputs" then [x, y, typ] = standard_inputs(arg1); case "getoutputs" then [x, y, typ] = standard_outputs(arg1); case "getorigin" then [x, y] = standard_origin(arg1); case 'set' then // Assignments here comes after assignments of the execution with the "define" flag x = arg1; // This line is essential, otherwise gives "Invalid index." error. graphics = arg1.graphics; exprs = graphics.exprs; model = arg1.model; if getInputFromSim == 1 then exec("macros/Kalman_Filter_Utils.sci",-1); // Not sure about this line in MATLAB, comment it if not necessary title = "Set Parameter"; labels = ['Initial state [x_dot(velocity), x(position)] which is position in ECEF frame and velocity'; 'Covariance which gives the uncertainty at position and velocity']; // Changed 'Stiffness' to 'Covariance' // In future we can add {'Accelerations', 'Orientations which is obation altitude control system'} types = list('vec', [2,1], 'mat', [2,2]); // Changed 'vec' to 'mat' for Covariance endLoop = %f; // Create a dialog for getting user inputs while ~endLoop do // Initialize dialog for parameters and initial state [ok, State, Covariance, exprs] = scicos_getvalue(title, labels, types, exprs); errMsg = []; // Check return set conditions of the initial state as per meetings if ~ok then // depends on what type of data we are having if State>0 // first condition of position and velocity errMsg = ["The velocity is positive [m/s]"]; end if condition2 // second condition of velocity errMsg = []; end if isempty(errMsg) then [model.rpar, isError] = EncodeRpar_KF(model.rpar, State, Covariance); graphics.exprs = exprs; x.graphics = graphics; x.model = model; endLoop = %t; // Check parameters // You can add additional checks for input parameters here if needed // Accept inputs and save them else messagebox(errMsg); error(errMsg, 20000); endLoop = %f; end else warning('Kalman_Filter_IF: Set: Cancel!'); endLoop = %t; end end else model.state = [concatAB(initial_state,initial_covariance)]; model.rpar = initial_covariance; // Use the covariance matrix as a parameter graphics.exprs = exprs; x.graphics = graphics; x.model = model; break message("Failed to update block io"); end // Concatenate the covariance matrix to the state vector // model.state = [State; Covariance(:)]; // Use the concatenation operator ":" for the matrix // Define block properties case 'define' // Create object model = scicos_model(); // Provide name and type model.sim = {'Kalman_Filter_sim', 5}; // what is case 4 and 5? https://help.scilab.org/scicos_model.html // Define inputs and outputs // One input with a variable-size "double" element model.in = [2;2]; // first dimension of the first input whcih is row 2*1 and 2*2 hence it will be [2;2] model.in2 = [1;2]; // the second dimension of I/P port is [1;2] from above model.intyp = [1;1]; // all the vector and matrices are real value model.out = [2;2]; // first dimension of the first output whcih is row 2*1 and 2*2 hence it will be [2;2] model.out2 = [1;2]; // the second dimension of O/P port is [1;2] from above model.outtyp = [1;1]; // all the vector and matrices are real value //model.state = [initial_state,matrix(initial_covariance)]; // Use the matrix concatenation operator ":" to convert matrix to column vector model.state=[State;Covariance] model.state = [concatAB(initial_state,initial_covariance)]; model.rpar = [initial_covariance(:)]; // Use the covariance matrix as a parameter // Define block properties model.blocktype = "c"; model.dep_ut = [%t,%f]; // what does %t and %f indicates? true and false // Set block properties exprs = ["[0.1; 0.0]";"1.0, 0.0; 0.0, 1.0"]; // How do we get this value? x = standard_define([4 4], model, exprs); x.graphics.style = ['blockWithLabel;displayedLabel=Kalman_Filter']; // other cases other than set or define sections end endfunction ``` The error is \>! Building macros… \>! Creation of [spacecraft\_gnc\_tbxlib] (Macros) – \>! genlib: Processing file: Common\_Utils.sci \>! genlib: Processing file: GravityGradient\_Utils.sci \>! genlib: Processing file: Gyroscope\_SIM.sci \>! genlib: Processing file: Gyroscope\_Utils.sci \>! genlib: Processing file: Kalman\_Filter\_IF.sci \>! genlib: Processing file: Kalman\_Filter\_IF.sci~ \>! genlib: Processing file: Kalman\_Filter\_Utils.sci \>! genlib: Processing file: MagneticField\_Utils.sci \>! genlib: Processing file: Magnetometer\_Utils.sci \>! genlib: Processing file: Magnetorquer\_Utils.sci \>! genlib: Processing file: ReactionWheel\_Utils.sci \>! genlib: Processing file: RigidBody\_Utils.sci \>! genlib: Processing file: StarTracker\_Utils.sci \>! Building blocks… \>! at line 8 of function scicos\_block ( C:\Program Files\scilab-2024.0.0\modules\scicos\macros\scicos\_scicos\scicos\_block.sci line 29 ) \>! at line 29 of function standard\_define ( C:\Program Files\scilab-2024.0.0\modules\scicos\macros\scicos\_scicos\standard\_define.sci line 50 ) \>! at line 110 of function Kalman\_Filter\_IF ( C:\Users\Vims\Desktop\spacecraft-gnc-tbx\macros\Kalman\_Filter\_IF.sci line 141 ) \>! at line 1 of executed string \>! at line 78 of function tbx\_build\_blocks ( C:\Program Files\scilab-2024.0.0\modules\modules\_manager\macros\tbx\_build\_blocks.sci line 90 ) \>! at line 7 of function buildmacros ( C:\Users\Vims\Desktop\spacecraft-gnc-tbx\macros\buildmacros.sce line 10 ) \>! at line 14 of executed file C:\Users\Vims\Desktop\spacecraft-gnc-tbx\macros\buildmacros.sce \>! at line 13 of function tbx\_builder ( C:\Program Files\scilab-2024.0.0\modules\modules\_manager\macros\tbx\_builder.sci line 26 ) \>! at line 40 of function tbx\_builder\_macros ( C:\Program Files\scilab-2024.0.0\modules\modules\_manager\macros\tbx\_builder\_macros.sci line 55 ) \>! at line 34 of function main\_builder ( C:\Users\Vims\Desktop\spacecraft-gnc-tbx\builder.sce line 43 ) \>! at line 50 of executed file C:\Users\Vims\Desktop\spacecraft-gnc-tbx\builder.sce \>! \>! scicos\_new: Wrong value for input argument #2: unable to set “model”. Can you please point out that where is the error?