Python port of the Control File Functions of Loggertools, the Logger Tools Software of Olaf Kolle, MPI-BGC Jena, (c) 2012. From the Logger Tools Software manual: "The functions range from simple mathematic operations to more complex and special procedures including functions for checking data. Most of the functions have the following appearance: y = f(x, p1, p2, ..., pn) where y is the variable in which the result of the function f is stored, x is the input variable of the function and p1 to pn are parameters (numbers) of the function. An output variable (result of a function) may be the same as an input variable. Some functions need more than one input variable, some functions do not need any parameter and some functions (mean, mini, maxi) may have a variable number of input variables."