.. _massage2:

&nbsp_place_holder;

> **_MASSAGE2_**

>

> **MASSAGE2** iteratively calls MASSAGE to refine adaptively according to a
gradient field. Thus, the **bisection_length** option must be a field.

>

> FORMAT:

>

> **massage2** / file_name / min_scale / bisection_length / merge_length /
toldamage / [tolroughness] / [ifirst,ilast,istride]/

&nbsp_place_holder;&nbsp_place_holder;&nbsp_place_holder; [**nosmooth**]/[**no
recon**][**strictmergelength**]/[**ignoremats**]/[**lite]**/[**checkaxy**]/[**
semiexclusive**]/**[exclusive**]

>

>

  
**file_name** is a file which contains a set of LaGriT commands that calculates the gradient field based on the distance field. In other words, the gradient field is a function of the distance field. It is necessary to have this file when using this routine, as the field must be updated after each refinement iteration.  
  
**_Creating user function file for MASSAGE2 routine_**
>

> This file contains a set of LaGriT commands which calculate the gradient
field for refinement based on the distance field.

>

> A file could be written like this:

>

> #user_function.mlgi

#An example of calculating the gradient field **F** as a linear function of
the distance field **D**

#Define some coefficients for the function

define / COEF_A /

define / COEF_B /

  
#Formula **F** = COEF_A * **D** + COEF_B

#First remove any distance field that exists and recompute the distance field

cmo / DELATT / mo_sink / dfield

compute / distance_field / mo_sink / mo_src / dfield

  
#Calculate **F**

math / multiply / mo_sink / ref_field / 1,0,0 / mo_sink / dfield / COEF_A

math / add / mo_sink / ref_field / 1,0,0 / mo_sink / ref_field / COEF_B

  
finish  The user does not have to put a floor value for the gradient field in
this case (unlike in MASSAGE), as MASSAGE2 will calculate the floor value
automatically. However, the minimum length scale 'min_scale' must be
specified.

  
The user must also create a node-based attribute for the gradient field before
calling MASSAGE2. In the example above, attribute 'ref_field' must already
exist in the mesh object. The name of the field must also match the
'field_name' argument in the MASSAGE2 command.

  
**min_scale** is the minimum length scale of the mesh (the minimum desired edge length).   
  
See [**MASSAGE**](MASSAGE.html) for other arguments.

>

> EXAMPLE:

>

> **massage2** / user_function.mlgi / 0.1 / ref_field / 1.e-5 / 1.e-5 /
strictmergelength