RsqC4photo(data, vmax = 39, alph = 0.04, kparm = 0.7, theta = 0.83, beta = 0.93, Rd = 0.8, iupperT = 37.5, ilowerT = 3, Catm = 380, b0 = 0.08, b1 = 3, StomWS = 1, response = c("Assim", "StomCond"))
\mu mol
m^{-2} s^{-1}). The second column should be
the observed quantum flux (\mu mol m^{-2}
s^{-1}). The third column should be observed
temperature of the leaf (Celsius). The fourth column
should be the observed relative humidity in proportion
(e.g. 0.7).c4photo function.c4photo function.c4photo function.c4photo function.c4photo function.c4photo function.c4photo function.\mumol/mol).'Assim' if you want an
R^2 for assimilation data and use 'StomCond'
if you want an R^2 for stomatal conductance data.numeric object
It simply returns the R^2 value for the given data
and coefficients.
This is an auxiliary function which is made available in case it is useful. It calculates the R-squared based on observed assimilation (or stomatal conductance) data and coefficients for the Collatz C4 photosynthesis model. The only coefficients being considered are Vcmax and alpha as described in the Collatz paper. At the moment it does not optimize k; this will be added soon. Notice that to be able to optimize k A/Ci type data are needed.
data(obsNaid) ## These data are from Naidu et al. (2003) ## in the correct format res <- RsqC4photo(obsNaid) ## Other example using Beale, Bint and Long (1996) data(obsBea) resB <- RsqC4photo(obsBea)