| Type | Intent | Optional | Attributes | Name | ||
|---|---|---|---|---|---|---|
| class(base_backend_t) | :: | self | ||||
| class(field_t), | intent(inout) | :: | du | |||
| class(field_t), | intent(in) | :: | u | |||
| class(tdsops_t), | intent(in) | :: | tdsops | 
transeq equation obtains the derivatives direction by direction, and the exact algorithm used to obtain these derivatives are decided at runtime. Backend implementations are responsible from directing calls to tds_solve to the correct algorithm.