Looping Structures Looping Structures In many cases, you will want the program to execute a block of code more than once. eV+ has three looping structures that allow you to execute blocks of code a variable number of times. The three instructions are: l FOR l DO...UNTIL l WHILE...DO FOR A FOR instruction creates an execution loop that will execute a given block of code a specified number of times. The basic form of a FOR loop is: FOR index = start_val TO end_val STEP incr . code block . END index is a real variable that keeps track of the number of times the FOR loop has been executed. This variable is available for use within the loop.
start_val is a real expression for the starting value of the index . end_val is a real expression for the ending value of the index . Execution of the loop terminates when index reaches this value. incr is a real expression indicating the amount index is to be incremented after each execution of the loop. The default value is 1. Examples 88 . 89 ; Output even elements of array "$names" (up to index 32) 90 91 FOR i = 2 TO 32 STEP 2 92 TYPE $names[i] 93 END 94 . . 102 . 103 ; Output the values of the 2 dimensional array "values" in 104 ; column and row form (10 rows by 10 columns) 105 .
106 FOR i = 1 TO 10 107 FOR j = 1 to 10 108 TYPE values[i,j], /S 109 END eV+Language User's Guide, v2.x, 18318-000 Rev A Page 72