# BBC BASIC Programmers' Reference

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finding_20the_20partial_20sum_20of_20an_20array

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 finding_20the_20partial_20sum_20of_20an_20array [2018/03/31 13:19]127.0.0.1 external edit finding_20the_20partial_20sum_20of_20an_20array [2018/04/17 16:14] (current)tbest3112 Added syntax highlighting 2018/04/17 16:14 tbest3112 Added syntax highlighting2018/03/31 13:19 external edit 2018/04/17 16:14 tbest3112 Added syntax highlighting2018/03/31 13:19 external edit Line 2: Line 2: //by Richard Russell, July 2015//\\ \\  The **SUM()** function returns the sum of all the elements in a numeric array, and it is much faster than summing the elements yourself in a loop. However you have no control over how many elements are summed: it is always the entire array. To find the sum of the first **n** elements of an array you can use a user-defined function as follows:​\\ ​ //by Richard Russell, July 2015//\\ \\  The **SUM()** function returns the sum of all the elements in a numeric array, and it is much faster than summing the elements yourself in a loop. However you have no control over how many elements are summed: it is always the entire array. To find the sum of the first **n** elements of an array you can use a user-defined function as follows:​\\ ​ + DIM array(999) DIM array(999) array() = 1 array() = 1 PRINT FNsum(array(),​ 500) PRINT FNsum(array(),​ 500) + ​ This program prints the value 500, being the sum of the first 500 elements of the array (0 to 499 inclusive). Here is the **FNsum()** function itself:​\\ ​ This program prints the value 500, being the sum of the first 500 elements of the array (0 to 499 inclusive). Here is the **FNsum()** function itself:​\\ ​ + DEF FNsum(a(), N%) DEF FNsum(a(), N%) IF DIM(a())<>​1 ERROR 0, "Array must be one-dimensional"​ IF DIM(a())<>​1 ERROR 0, "Array must be one-dimensional"​ Line 11: Line 14: !(!^a()+1) = N% !(!^a()+1) = N% = SUM(a()) = SUM(a()) +
finding_20the_20partial_20sum_20of_20an_20array.txt · Last modified: 2018/04/17 16:14 by tbest3112

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