这篇文章主要介绍了PHP基于自定义函数生成笛卡尔积的方法,结合具体实例形式分析了php使用数组运算模拟集合实现笛卡尔积运算的相关操作技巧,需要的朋友可以参考下。

本文实例讲述了PHP基于自定义函数生成笛卡尔积的方法，分享给大家供大家参考，具体如下：

1. <?php
2. $color = array('red', 'green');
3. $size = array(39, 40, 41);
4. $local = array('beijing', 'shanghai');
5. echo "<pre>";
6. print_r(combineDika($color, $size, $local));
7. /**
8. * 所有数组的笛卡尔积
9. *
10. * @param unknown_type $data
11. */
12. function combineDika() {
13. $data = func_get_args();
14. $cnt = count($data);
15. $result = array();
16. foreach($data[0] as $item) {
17. $result[] = array($item);
18. }
19. for($i = 1; $i < $cnt; $i++) {
20. $result = combineArray($result,$data[$i]);
21. }
22. return $result;
23. }
24. /**
25. * 两个数组的笛卡尔积
26. *
27. * @param unknown_type $arr1
28. * @param unknown_type $arr2
29. */
30. function combineArray($arr1,$arr2) {
31. $result = array();
32. foreach ($arr1 as $item1) {
33. foreach ($arr2 as $item2) {
34. $temp = $item1;
35. $temp[] = $item2;
36. $result[] = $temp;
37. }
38. }
39. return $result;
40. }
41. ?>

运行结果：

1. Array
2. (
3. [0] => Array
4. (
5. [0] => red
6. [1] => 39
7. [2] => beijing
8. )
9. [1] => Array
10. (
11. [0] => red
12. [1] => 39
13. [2] => shanghai
14. )
15. [2] => Array
16. (
17. [0] => red
18. [1] => 40
19. [2] => beijing
20. )
21. [3] => Array
22. (
23. [0] => red
24. [1] => 40
25. [2] => shanghai
26. )
27. [4] => Array
28. (
29. [0] => red
30. [1] => 41
31. [2] => beijing
32. )
33. [5] => Array
34. (
35. [0] => red
36. [1] => 41
37. [2] => shanghai
38. )
39. [6] => Array
40. (
41. [0] => green
42. [1] => 39
43. [2] => beijing
44. )
45. [7] => Array
46. (
47. [0] => green
48. [1] => 39
49. [2] => shanghai
50. )
51. [8] => Array
52. (
53. [0] => green
54. [1] => 40
55. [2] => beijing
56. )
57. [9] => Array
58. (
59. [0] => green
60. [1] => 40
61. [2] => shanghai
62. )
63. [10] => Array
64. (
65. [0] => green
66. [1] => 41
67. [2] => beijing
68. )
69. [11] => Array
70. (
71. [0] => green
72. [1] => 41
73. [2] => shanghai
74. )
75. )