# How to setup or define model input argument Scilab/XCOS?

**URL:** https://scilab.discourse.group/t/how-to-setup-or-define-model-input-argument-scilab-xcos/470
**Category:** Xcos
**Created:** [April 16, 2024, 10:17pm UTC](https://scilab.discourse.group/t/how-to-setup-or-define-model-input-argument-scilab-xcos/470 "2024-04-16T22:17:21Z")
**Posts on this page:** 1
**Page:** 1

<div class="post-metadata">

### 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, 10:17pm UTC](https://scilab.discourse.group/t/how-to-setup-or-define-model-input-argument-scilab-xcos/470/1 "2024-04-16T22:17:21Z")

</div>

```auto
    case "define" then
        // default values
        x0 = [0; 0]
        k_stiff = 1
        
        // create object
        model=scicos_model()
        // provide name and type
        model.sim = list("SCGNC_example_sim",5)
        // define inputs and outputs
        // one inputs with a variable size "double" element
        model.in = 1
        model.intyp = 1
        // one output with a single "double" element
        model.out = 1
        model.outtyp = 1
        // set initial state
        model.state = x0
        // set default parameter
        model.rpar = k_stiff
        // define block properties
        model.blocktype = "c"
        model.dep_ut = [%t %f]

        // set block properties
        exprs = ["[0.0; 0.0]";"1.0"];
        x = standard_define([4 4],model,exprs)
        x.graphics.style = ["blockWithLabel;displayedLabel=SCGNC_example"]

```

1-I have read the [model define](https://help.scilab.org/scicos_model) but I did not understand the

evtin,evtout,state,rpar, all the other but there is no example and how certain value in **rpar,exprs,state** came?

2- How to define such value and what/why shape/size of the **rpar,exprs,state** are obtained?  
3-From where the value came?