Commodore Plus 4 - Page 52

40 The BASIC Language
EXIT Abbr. exl
Terminates a DO ... LOOP conditional command sequence. You cannot use
EXIT with other commands, including IF ... THEN ... ELSE sequences. See
DO.
EXP Abbr. eX
EXP (number)
Numeric function that finds the value of the mathematical constant e (approx
imately 2.71828183) raised to the power in parentheses. To find exponentials of
other numbers, use the up arrow symbol.
Parameter: any numeric expression
Example: PRINT EXP(-1) Displays the reciprocal of e.
.367879441
FOR ... TO ... STEP ... NEXT Abbrs. fO/to/stE/nE
FOR variable = start value TO end value STEP increment
commands
NEXT variable, variable, etc.
Creates a loop to repeatedly execute all commands between the FOR com
mand and the NEXT command. The loop repeats until the counter variable in the
FOR command equals or exceeds the value of the ending point.
If you omit the optional STEP command, the FOR counter is incremented by 1
each time the loop executes. You can use STEP to increment the counter by any
number. For example, you can use a STEP increment of 25 to draw a shape
repeatedly, each time tilted 25 degrees more. You can also use STEP to count
backwards by specifying a negative number.
Parameters: FOR counter variable = starting point TO ending point STEP increment
commands
NEXT counter variable
1. The FOR command contains a variable whose value is updated each time
the loop is executed.
The FOR command also contains the starting and ending points for the
number of times the loop will execute. The starting and ending points can have
any value, including variables. If the starting point is higher than the ending
point, you normally include a negative STEP value.
2. The STEP clause, which is optional, tells the computer how much to add to
the current value of the counter each time the NEXT command sends execution
back to the FOR command. The default value is 1.