chapter04sum1000.pro

idl 可视化分析与应用（随书程序）

; Chapter04Sum1000.pro
PRO Chapter04Sum1000
sum = 0L
i = 1
WHILE  i LE 1000  DO  BEGIN
    sum = sum + i
    i++
ENDWHILE
PRINT,  ' 1 + 2 + … + 1000 = ',  sum
END