Synopsis:

       answer = fp_pow(number,power[, decimals])

Arguments:

       number - The number to raise to a power

       power - The power by which to raise the number

       [decimals] - Optional argument to specify the number of decimal places of the returned result

Description:  Returns the number raised to the power specified by power (sometimes written x^y or x**y).

In the event of an error, e.g. fp_pow(-1, "0.5"), the function will return the string "ERROR" and an error message will be written to the error log file.

This function has an optional additional argument specifying the number of decimal places used for rounding (decimals).  The initial default number of decimal places used for rounding is 2, this default value may be changed by calling fp_decs(n) where n is 0 to 9 specifying the number of decimal places. The current default is over-ridden by specifying an explicit number of decimals.

Returns:   Returns the result of raising number by the power specified by power or else the string "ERROR" if invalid values are specified (E.g. trying to take the square root of a negative number)