# Parameter Command
In DDM-based FE response sensitivity analysis, the sensitivity parameters can be material,
geometry or discrete loading parameters. Each parameter should be defined as:
```tcl parameter $tag <specific object arguments> ```

tag

integer tag identifying the parameter.

<specific object arguments>

depend on the object in the FE model encapsulating the desired parameters.

Note: Each parameter must be unique in the FE domain, and all parameter tags must be numbered sequentially starting from 1.


EXAMPLE

```tcl parameter 1 element 4 section 3 material 1 E ```

defined), the <specific object arguments> string becomes:

```tcl parameter 1 element 4 section 3 E ```

simplifies as:

```tcl parameter 1 element 4 material 1 E ```


Notice that the format of the <specific object arguments> is different for each considered element/section/material. The user is referred to the corresponding section of this manual for the specific set of parameters and the relative <specific object arguments> format.