# Two couplings to one interface reloaded

**URL:** <https://precice.discourse.group/t/two-couplings-to-one-interface-reloaded/260>\
**Category:** Using preCICE\
**Tags:** multi-coupling, coupling-schemes\
**Created:** [June 24, 2020, 7:03pm UTC](https://precice.discourse.group/t/two-couplings-to-one-interface-reloaded/260 "2020-06-24T19:03:22Z")\
**Posts on this page:** 1\
**Showing post:** 4

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**Author:** ![uekerman](https://yyz2.discourse-cdn.com/free1/user_avatar/precice.discourse.group/uekerman/32/2199_2.png) [@uekerman](https://precice.discourse.group/u/uekerman)\
**Post date:** [July 1, 2020, 8:58am UTC](https://precice.discourse.group/t/two-couplings-to-one-interface-reloaded/260/4 "2020-07-01T08:58:36Z")

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Sry for the late reply. This is really a tricky case. I am afraid there is no simple solution though there should be one. Let me think a bit more about this. I think I understand your case.

The summation action already helps quite a bit. The feature will be released with v2.1 end of July 2020. It’s already implemented and merged to develop.

Issue: [https://github.com/precice/precice/issues/699](https://github.com/precice/precice/issues/699)  
PR: [https://github.com/precice/precice/pull/707](https://github.com/precice/precice/pull/707)  
[Example integration test](https://github.com/precice/precice/blob/develop/src/precice/tests/SerialTests.cpp#L1453) with [corresponding config](https://github.com/precice/precice/blob/develop/src/precice/tests/summation-action.xml).

An ugly workaround could be to treat “A” as two participants: “A\_bottom” and “A\_top”. So if A uses the C++ API to create two `SolverInterfaces`.

Btw, problem with the documentation is indeed that we don’t have versions for the documentation yet. That’s why the feature is listed in the wiki, but not in the xml reference. With the new user documentation this should get better. See also: [Restructuring precice.org and unifying the documentation](https://precice.discourse.group/t/restructuring-precice-org-and-unifying-the-documentation/215).

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