Cleanup of SubDyn module

[ebranlard]

Complete this sentence
THIS PULL REQUEST IS READY TO MERGE

Feature or improvement description

Removed about 1500 lines in two of the main SubDyn files, for code readability. I'll be working on a important re-write of the SubDyn module, so I'd like to commit this before I start doing updates to the code.

Most of the lines removed were gained from using a more concise error handling (see #272), and gathering copy-pasted calls into "contained"subroutines at the end. The input file routine for instance is significantly more condensed and readable. Note that I usually use the concise error handling on parts of the code that are only called "once", to limit additional overhead.

Automated test results

I've run 5 different SubDyn test cases. Hopefully the regression test will capture that as well.

Below is an example of the subfunctions I usually introduce at the end of a routine

   LOGICAL FUNCTION Check(Condition, ErrMsg_in)
        logical, intent(in) :: Condition
        character(len=*), intent(in) :: ErrMsg_in
        Check=Condition
        if (Check) call Abort(' Error in file '//TRIM(SDInputFile)//': '//trim(ErrMsg_in))
   END FUNCTION Check

   LOGICAL FUNCTION Failed()
        call SetErrStat(ErrStat2, ErrMsg2, ErrStat, ErrMsg, 'SD_Input') 
        Failed =  ErrStat >= AbortErrLev
        if (Failed) call CleanUp()
   END FUNCTION Failed

   SUBROUTINE Abort(ErrMsg_in)
      character(len=*), intent(in) :: ErrMsg_in
      CALL SetErrStat(ErrID_Fatal, ErrMsg_in, ErrStat, ErrMsg, 'SD_Input');
      CALL CleanUp()
   END SUBROUTINE Abort

   SUBROUTINE CleanUp()
      CLOSE( UnIn )
      IF (Echo) CLOSE( UnEc )
   END SUBROUTINE

[bjonkman]

I'd prefer the Abort() subroutine be called something else since there is a built-in portability routine called abort: https://software.intel.com/en-us/fortran-compiler-developer-guide-and-reference-abort

[ebranlard]

Oh, right, I'll change that! I've replaced it with Fatal.

[rafmudaf]

@ebranlard Are these if-statements correct? At least the error messages may not be...

[rafmudaf]

I'm questioning because the original code allowed FEMMod 1, 2, 3 or 4.

[ebranlard]

Yes, only 1 and 3 are implemented so far. These if statements were located in a for loop (line 688 of the old code), and as Bonnie noted, these could be put outside.

[rafmudaf]

nn is used later but not allocated. Is this ok?

[ebranlard]

I allocated it line 484 of the new code. A lot of the code assumes that the number of nodes is 2, and I don't think we'll support higher number of nodes anytime soon. In fact I'll likely have to get rid of this variable in the next implementation.

[rafmudaf]

I've looked over all changes and everything looks good to me. @ebranlard Thanks a lot!

[rafmudaf]

What do you think about replacing all older Fortran number comparisons (i.e. .LT.) with the more modern version: <? Currently, there is mixed usage throughout SubDyn and OpenFAST.

[andrew-platt]

Sounds reasonable to me to change the < and other symbols. I don't know that I would bother changing them over all modules, but maybe in modules you happen to be working on.

[rafmudaf]

@andrew-platt I was thinking just in SubDyn since so many formatting changes are already here

[ebranlard]

I've changed these signs in my recent commit.

[rafmudaf]

The SubDyn related tests pass on Eagle:

(/home/rmudafor/.conda-envs/openfast) >>eagle@~/Development/openfast/build $ ctest -j 3 -L subdyn
Test project /home/rmudafor/Development/openfast/build
    Start 20: 5MW_OC4Jckt_DLL_WTurb_WavesIrr_MGrowth
    Start 19: 5MW_OC3Trpd_DLL_WSt_WavesReg
    Start 18: 5MW_OC3Mnpl_DLL_WTurb_WavesIrr
    
1/3 Test #18: 5MW_OC3Mnpl_DLL_WTurb_WavesIrr ...........   Passed  172.47 sec
2/3 Test #19: 5MW_OC3Trpd_DLL_WSt_WavesReg .............   Passed  496.60 sec
3/3 Test #20: 5MW_OC4Jckt_DLL_WTurb_WavesIrr_MGrowth ...   Passed  1152.27 sec

100% tests passed, 0 tests failed out of 3

Label Time Summary:
aerodyn15    = 1821.34 sec*proc (3 tests)
elastodyn    = 1821.34 sec*proc (3 tests)
hydrodyn     = 1821.34 sec*proc (3 tests)
openfast     = 1821.34 sec*proc (3 tests)
servodyn     = 1821.34 sec*proc (3 tests)
subdyn       = 1821.34 sec*proc (3 tests)

Total Test time (real) = 1152.31 sec