LOG

Action: Returns the natural logarithm (log to the base of e) of the argument. If the value of the argument is zero or negative the BASIC error message ?ILLEGAL QUANTITY will occur.

   25 PRINT LOG(45/7)
    1.86075234

   10 NUM=LOG(ARG)/LOG(10)  (Calculates the LOG of ARG to the base 10)

MID$

Action: The MID$ function returns a sub-string which is taken from within a larger <string> argument. The starting position of the sub-string is defined by the <numeric-1> argument and the length of the sub-string by the <numeric-2> argument. Both of the numeric arguments can have values ranging from 0 to 255.

If the <numeric-1> value is greater than the length of the <string>, or if the <numeric-2> value is zero, then MID$ gives a null string value. If the <numeric-2> argument is left out, then the computer will assume that a length of the rest of the string is to be used. And if the source string has fewer characters than <numeric-2>, from the starting position to the end of the string argument, then the whole rest of the string is used.

   10 A$="GOOD"
   20 B$="MORNING EVENING AFTERNOON"
   30 PRINT A$ + MID$(B$,8,8)

   GOOD EVENING