| Type | Intent | Optional | Attributes | Name | ||
|---|---|---|---|---|---|---|
| class(base_backend_t) | :: | self | ||||
| class(field_t), | intent(inout) | :: | u | |||
| class(field_t), | intent(in) | :: | u_ | 
sum9into3 subroutine combines all the directional velocity derivatives into the corresponding x directional fields.