# ET_COUPLING

References: Kondov2007, Futera2017

specifies the two constraints/restraints for extracting ET coupling elements [Edit on GitHub]

Subsections

- DDAPC_RESTRAINT_A
- DDAPC_RESTRAINT_B
- PROGRAM_RUN_INFO
- PROJECTION

## Keywords

- TYPE_OF_CONSTRAINT

## Keyword descriptions

TYPE_OF_CONSTRAINT: enum = NONE

  Usage: TYPE_OF_CONSTRAINT DDAPC

  Valid values:

  - `NONE` NONE

  - `DDAPC` DDAPC Constraint

  Specifies the type of constraint [Edit on GitHub]