Commodore 128 System Manual page 306

RENUMBER
R enum ber lines of a BASIC program
RENUMBER [new starting line number] [.increment]
[,old starting line number]
The new starting line is the number of the first line in the program
after renumbering; the default value is 10. The increment is the
interval between line numbers, (i.e., 10, 20, 30, etc.); the
increment default value is also 10. The old starting line number is
the first line number before you renumber the program. This
allows renumbering of a select portion of the program. The
default in this case is the first line of the program. This command
can only be executed from direct mode.
A " UNRESOLVED REFERENCE ERROR'' occurs if any reference
to line number that does not exist is encountered. An " OUT OF
MEMORY" occurs if RENUMBERing expands the program
beyond its limits. A " LINE NUMBER TOO LARGE ERROR"
occurs if RENUMBER generates a line number of 64000 or
higher. These errors leave the program unharmed.
EXAMPLES:
RENUMBER
Renumbers the program starting at 10, and increments each
additional line by 10.
RENUMBER 20, 20, 15
Starting at line 15, renumbers the program. Line 15 becomes line
20, and other lines are numbered in increments of 20.
RENUMBER,, 65
Starting at line 65, renumbers in increments of 10. Line 65
becomes line 10. If you omit a parameter, you must still enter a
comma as a placeholder. There must be no line between 10 and
64 inclusive.
ALWAYS SAVE YOUR PROGRAM BEFORE RENUMBERING,
because very long programs can cause a SYSTEM crash when
RENUMBERed with larger line numbers.
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