Avoid in-code checks of PFT type

[samsrabin]

We have a bunch of integer variables in pftconMod that are unique IDs for each PFT ("vegetation type constants"):

CTSM/src/main/pftconMod.F90

Lines 19 to 101 in d6f950a

	! Vegetation type constants
	!
	integer, public :: noveg ! value for not vegetated
	integer, public :: ndllf_evr_tmp_tree ! value for Needleleaf evergreen temperate tree
	integer, public :: ndllf_evr_brl_tree ! value for Needleleaf evergreen boreal tree
	integer, public :: ndllf_dcd_brl_tree ! value for Needleleaf deciduous boreal tree
	integer, public :: nbrdlf_evr_trp_tree ! value for Broadleaf evergreen tropical tree
	integer, public :: nbrdlf_evr_tmp_tree ! value for Broadleaf evergreen temperate tree
	integer, public :: nbrdlf_dcd_trp_tree ! value for Broadleaf deciduous tropical tree
	integer, public :: nbrdlf_dcd_tmp_tree ! value for Broadleaf deciduous temperate tree
	integer, public :: nbrdlf_dcd_brl_tree ! value for Broadleaf deciduous boreal tree
	integer, public :: nbrdlf_evr_shrub ! value for Broadleaf evergreen shrub
	integer, public :: nbrdlf_dcd_tmp_shrub ! value for Broadleaf deciduous temperate shrub
	integer, public :: nbrdlf_dcd_brl_shrub ! value for Broadleaf deciduous boreal shrub
	integer, public :: nc3_arctic_grass ! value for C3 arctic grass
	integer, public :: nc3_nonarctic_grass ! value for C3 non-arctic grass
	integer, public :: nc4_grass ! value for C4 grass
	integer, public :: npcropmin ! value for first crop
	integer, public :: ntmp_corn ! value for temperate corn, rain fed (rf)
	integer, public :: nirrig_tmp_corn ! value for temperate corn, irrigated (ir)
	integer, public :: nswheat ! value for spring temperate cereal (rf)
	integer, public :: nirrig_swheat ! value for spring temperate cereal (ir)
	integer, public :: nwwheat ! value for winter temperate cereal (rf)
	integer, public :: nirrig_wwheat ! value for winter temperate cereal (ir)
	integer, public :: ntmp_soybean ! value for temperate soybean (rf)
	integer, public :: nirrig_tmp_soybean ! value for temperate soybean (ir)
	integer, public :: nbarley ! value for spring barley (rf)
	integer, public :: nirrig_barley ! value for spring barley (ir)
	integer, public :: nwbarley ! value for winter barley (rf)
	integer, public :: nirrig_wbarley ! value for winter barley (ir)
	integer, public :: nrye ! value for spring rye (rf)
	integer, public :: nirrig_rye ! value for spring rye (ir)
	integer, public :: nwrye ! value for winter rye (rf)
	integer, public :: nirrig_wrye ! value for winter rye (ir)
	integer, public :: ncassava ! ...and so on
	integer, public :: nirrig_cassava
	integer, public :: ncitrus
	integer, public :: nirrig_citrus
	integer, public :: ncocoa
	integer, public :: nirrig_cocoa
	integer, public :: ncoffee
	integer, public :: nirrig_coffee
	integer, public :: ncotton
	integer, public :: nirrig_cotton
	integer, public :: ndatepalm
	integer, public :: nirrig_datepalm
	integer, public :: nfoddergrass
	integer, public :: nirrig_foddergrass
	integer, public :: ngrapes
	integer, public :: nirrig_grapes
	integer, public :: ngroundnuts
	integer, public :: nirrig_groundnuts
	integer, public :: nmillet
	integer, public :: nirrig_millet
	integer, public :: noilpalm
	integer, public :: nirrig_oilpalm
	integer, public :: npotatoes
	integer, public :: nirrig_potatoes
	integer, public :: npulses
	integer, public :: nirrig_pulses
	integer, public :: nrapeseed
	integer, public :: nirrig_rapeseed
	integer, public :: nrice
	integer, public :: nirrig_rice
	integer, public :: nsorghum
	integer, public :: nirrig_sorghum
	integer, public :: nsugarbeet
	integer, public :: nirrig_sugarbeet
	integer, public :: nsugarcane
	integer, public :: nirrig_sugarcane
	integer, public :: nsunflower
	integer, public :: nirrig_sunflower
	integer, public :: nmiscanthus
	integer, public :: nirrig_miscanthus
	integer, public :: nswitchgrass
	integer, public :: nirrig_switchgrass
	integer, public :: ntrp_corn !value for tropical corn (rf)
	integer, public :: nirrig_trp_corn !value for tropical corn (ir)
	integer, public :: ntrp_soybean !value for tropical soybean (rf)
	integer, public :: nirrig_trp_soybean !value for tropical soybean (ir)
	integer, public :: npcropmax ! value for last prognostic crop in list
	integer, public :: nc3crop ! value for generic crop (rf)
	integer, public :: nc3irrig ! value for irrigated generic crop (ir)

These are used throughout the code in checks like veg_type == ndllf_evr_tmp_tree. We should move to using the parameter file for this instead, to facilitate changing PFT characteristics and adding new ones. For example, the ISIMIP runs may require some unused PFTs to be replaced with different ones, which will necessitate not just changing the parameter file but also looking through the code for these manual checks. In addition, it would make the affected code easier to read.

This especially makes things hard for non-developers trying to develop new crops (e.g.). They have to scour the code for places where PFT integers might need to be used.

Although I think this would be an easy job, it wouldn't have to happen all at once. There's some very low-hanging fruit out there. For instance, this could be replaced with a gdd20_type parameter:

CTSM/src/biogeochem/CNPhenologyMod.F90

Lines 2878 to 2896 in d6f950a

	! which GDD*20 variable does this crop use?
	if (ivt(p) == ntmp_soybean .or. ivt(p) == nirrig_tmp_soybean .or. &
	ivt(p) == ntrp_soybean .or. ivt(p) == nirrig_trp_soybean) then
	gdd20 = gdd1020(p)
	else if (ivt(p) == ntmp_corn .or. ivt(p) == nirrig_tmp_corn .or. &
	ivt(p) == ntrp_corn .or. ivt(p) == nirrig_trp_corn .or. &
	ivt(p) == nsugarcane .or. ivt(p) == nirrig_sugarcane .or. &
	ivt(p) == nmiscanthus .or. ivt(p) == nirrig_miscanthus .or. &
	ivt(p) == nswitchgrass .or. ivt(p) == nirrig_switchgrass) then
	gdd20 = gdd820(p)
	else if (ivt(p) == nswheat .or. ivt(p) == nirrig_swheat .or. &
	ivt(p) == nwwheat .or. ivt(p) == nirrig_wwheat .or. &
	ivt(p) == ncotton .or. ivt(p) == nirrig_cotton .or. &
	ivt(p) == nrice .or. ivt(p) == nirrig_rice) then
	gdd20 = gdd020(p)
	else
	write(iulog, *) 'ERROR: PlantCrop(): unrecognized ivt for gdd20: ',ivt(p)
	call endrun(msg="Stopping")
	end if

Note that fully resolving this would also necessarily involve solving Issue #21.

[samsrabin]

From src/, this command will work to find all instances of any vegetation type constant, including noveg, npcropmin, and npcropmax:

grep -C 1 -E -r --color '\bnoveg\b|\bndllf_evr_tmp_tree\b|\bndllf_evr_brl_tree\b|\bndllf_dcd_brl_tree\b|\bnbrdlf_evr_trp_tree\b|\bnbrdlf_evr_tmp_tree\b|\bnbrdlf_dcd_trp_tree\b|\bnbrdlf_dcd_tmp_tree\b|\bnbrdlf_dcd_brl_tree\b|\bnbrdlf_evr_shrub\b|\bnbrdlf_dcd_tmp_shrub\b|\bnbrdlf_dcd_brl_shrub\b|\bnc3_arctic_grass\b|\bnc3_nonarctic_grass\b|\bnc4_grass\b|\bnpcropmin\b|\bntmp_corn\b|\bnirrig_tmp_corn\b|\bnswheat\b|\bnirrig_swheat\b|\bnwwheat\b|\bnirrig_wwheat\b|\bntmp_soybean\b|\bnirrig_tmp_soybean\b|\bnbarley\b|\bnirrig_barley\b|\bnwbarley\b|\bnirrig_wbarley\b|\bnrye\b|\bnirrig_rye\b|\bnwrye\b|\bnirrig_wrye\b|\bncassava\b|\bnirrig_cassava\b|\bncitrus\b|\bnirrig_citrus\b|\bncocoa\b|\bnirrig_cocoa\b|\bncoffee\b|\bnirrig_coffee\b|\bncotton\b|\bnirrig_cotton\b|\bndatepalm\b|\bnirrig_datepalm\b|\bnfoddergrass\b|\bnirrig_foddergrass\b|\bngrapes\b|\bnirrig_grapes\b|\bngroundnuts\b|\bnirrig_groundnuts\b|\bnmillet\b|\bnirrig_millet\b|\bnoilpalm\b|\bnirrig_oilpalm\b|\bnpotatoes\b|\bnirrig_potatoes\b|\bnpulses\b|\bnirrig_pulses\b|\bnrapeseed\b|\bnirrig_rapeseed\b|\bnrice\b|\bnirrig_rice\b|\bnsorghum\b|\bnirrig_sorghum\b|\bnsugarbeet\b|\bnirrig_sugarbeet\b|\bnsugarcane\b|\bnirrig_sugarcane\b|\bnsunflower\b|\bnirrig_sunflower\b|\bnmiscanthus\b|\bnirrig_miscanthus\b|\bnswitchgrass\b|\bnirrig_switchgrass\b|\bntrp_corn\b|\bnirrig_trp_corn\b|\bntrp_soybean\b|\bnirrig_trp_soybean\b|\bnpcropmax\b|\bnc3crop\b|\bnc3irrig\b' $(find . -name "*F90")```

[samsrabin]

@mvdebolskiy points out: Use int instead of logical on the paramfile for performance reasons.