| Line 1: |
Line 1: |
| − | '''Recursion''' is a technique whereby a [[function]], in order to accomplish a task, calls itself to accomplish part of the task. | + | '''Recursion''' is the repeated application of a procedure or definition through reference to itself. |
| | + | |
| | + | ==In Mathematics== |
| | + | |
| | + | There's a simple procedure for finding out whether a number is divisible by three. |
| | + | #If the number is 3, 6, or 9 then it's divisible by three. |
| | + | #Otherwise, add all the digits of the number; if the sum of the digits is divisible by three, then so is the original number. |
| | + | |
| | + | Examples: |
| | + | * 12 => 1 + 2 = 3 (yes) |
| | + | * 14 => 1 + 4 = 5 (no) |
| | + | * 96 => 9 + 6 = 15; 15 => 1 + 5 = 6 |
| | + | |
| | + | |
| | + | ==In Computing== |
| | + | |
| | + | Recursion is a technique whereby a [[function]], in order to accomplish a task, calls itself to accomplish part of the task. |
| | | | |
| | Every recursive solution involves two major parts or cases, the second part having three components: | | Every recursive solution involves two major parts or cases, the second part having three components: |
| Line 13: |
Line 29: |
| | :1. Write a function to compute the sum of all numbers from 1 to n. | | :1. Write a function to compute the sum of all numbers from 1 to n. |
| | :2. Write a function to compute 2 to the power of a non-negative integer. | | :2. Write a function to compute 2 to the power of a non-negative integer. |
| − | :3. Write a function to compute any number to the power of a non-negative integer. | + | :3. Write a function to compute any number to the power of a non-negative integer. |
| | + | |
| | + | ==External links== |
| | + | * [http://ocw.mit.edu/courses/electrical-engineering-and-computer-science/6-00sc-introduction-to-computer-science-and-programming-spring-2011/unit-1/lecture-6-recursion/ Unit on recursion in free online computer science course from MIT.] |
| | | | |
| | [[Category:Computer Science]] | | [[Category:Computer Science]] |
| | + | [[Category:Mathematics]] |