AVGMODE: Mode average of a series of numbers
syntax: AVGMODE(n, x1, x2, x3, ...) or
AVGMODE(<filename>)
Returns the mode (frequency) average of a series of numbers. Input consists of
a series of numbers with the first argument specifying the number of elements
in the series or a single argument specifying the name of the plain text file
containing the series of numbers with each element in the file seperated by
spaces or starting at a new line. Note: no attempt is made to return more than
one element even though more than one element in the series can have the same
highest occurence frequency.