$useevprofile

If the user needs to use field dependent mobility profile, he has several way to achieve this. The first way is to call $usefieldmufunc , $useemufunc, $useemunfunc, $useemupfunc. However, for this one, you will need to write the code by yourself. The other way is to give the program a E versus velocity table files. And you need to setup the region $xend and $yend to decide which region to use this profile.
Note that his function current is only support Ex field for electron transport in x direction since this function is for FET transistor case. It does not support for holes, neither. When this function is called, other regions or unsupported direction such as Ey or holes will use the constant mobility model.

Format:

$useevprofile
E-versus-v_filename
$N_{total}$ format_type
$N_{sep}$

Format_type:
1: 
2:
3: Two different segments, N_sep separaet this two segments 

$N_{sep}$: which_column_the_second_format_start
$N_{total}$: total column number 

File format of E-versus-v_filename:

$Ex1_1~~~ V_1$
$Ex1_2~~~ V_2$
$Ex1_3~~~ V_3$
....
....
.... to N_sep-1
$Ex2_{N_{sep}-1}~~~ V_1$
$Ex2_{N_{sep}-1}~~~ V_2$
$Ex2_{N_{sep}-1}~~~ V_3$
....
....
 $Ex2_{N_{total}}~~~ V_{1}$

For examples:

$useevprofile
mcalgan32-GaN-InGaN.inp.vfoc.res
174 3
131

$xend
89.9999e-04 116.000001e-4

$yend
4.2001e-04 4.000e-04