SCULIB_SKYFUNC

Return the value of the skydip function

This routine returns the value of the skydip function. The parameters are passed as follows:

This subroutine returns the theoretical value of the skydip for the given input parameters.

J_{}

theory = (1-

η_{}

tel) J_tel + $η_{}$

telJ_atm (1-B $e x p (- τ A i r m a s s)) (71)$

J_{}

atm = J_amb X_G (72)

X_{G} = 1 + \frac{h 1 \times h 2}{J_{}}

amb

e x p (- τ \times A i r m a s s (i) / X_G c o n s t) (73)

CALL SCULIB_SKYFUNC(F, X, P, M)

The value of the skydip function

The airmass used to calculate the function

The parameter values

The number of parameters