computes temperature correction factor



TC = tempcorr (T, T_ref, pars_T)


Calculates the factor with which physiological rates should be multiplied
  to go from a reference temperature to a given temperature.
The 3-parameter version models low or high temerature torpor, depending the the value of the boudary temparature, relative to the  reference temperatur, the 5-parameter version models both.
The 5- parameter version assumes that the reference temperature is between the lower and upper temperature boundaries.


  1: T_A: Arrhenius temperature
  3: T_A, T_L, T_AL or T_A, T_H, T_AH: Arrhenius temperature, boundary temperature, Arrhenius temperature for that boundary temperature
  5: T_A, T_L, T_H, T_AL, T_AH



The intended use is: (rate at  T) = (rate at T_ref) * tempcorr (T, T_ref, pars_T).
Notice that tempcorr (T_ref, T_ref, pars_T) results in the value 1, independent of pars_T.
Notice also that the result with one parameter is always larger than with 3 or 5 parameters, with the same first parameter.
The Arrhenius temperature T_A affects rates at the full temperature-range.
The interpretation of the parameters in the 3-parameter version depends on the value of pars_T(2), relative to T_ref.
If pars_T(2) < T_ref, it is assumed that T_L = pars_T(2) and T_AL = pars_T(3), and low-temperature torpor is modelled.
If pars_T(2) > T_ref, it is assumed that T_H = pars_T(2) and T_AH = pars_T(3), and high-temperature torpor is modelled.
Low-temperature torpor does not affect rates at temperatures larger than T_ref; the reverse applies for high-temperature torpor.
This also holds for the 5-parameter version.
<shtempcorr.html *shtempcorr*> shows a graph of this correction factor as function of the temperature.

Example of use

tempcorr([330 331 332], 320, [12000 277 318 20000 190000]) and
shtemp2corr(320, [12000 277 318 20000 190000]).