Total Complexity | 10 |
Total Lines | 56 |
Duplicated Lines | 0 % |
Coverage | 38.89% |
Changes | 1 | ||
Bugs | 0 | Features | 0 |
1 | <?php |
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16 | trait FMAT |
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17 | { |
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18 | /** |
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19 | * 返回数的阶乘 |
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20 | * |
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21 | * @param integer|double $number 必需。 要计算其阶乘的非负数。 如果 number 不是整数,将被截尾取整 |
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22 | * |
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23 | * @return integer |
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24 | */ |
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25 | 2 | public static function fact($number) |
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26 | { |
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27 | 2 | $number = (int) floor($number); |
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28 | 2 | if ($number == 0) { |
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29 | return 1; |
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30 | } |
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31 | 2 | $result = 1; |
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32 | 2 | foreach (Arrays::rangeGenerator(1, $number) as $num) { |
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33 | 2 | $result *= $num; |
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34 | } |
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35 | 2 | return $result; |
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36 | } |
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37 | |||
38 | /** |
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39 | * 返回数字的双倍阶乘 |
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40 | * |
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41 | * - 偶数:n!! = n * (n - 2) * (n - 4) * ... * 4 * 2 |
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42 | * - 奇数:n!! = n * (n - 2) * (n - 4) * ... * 3 * 1 |
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43 | * |
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44 | * @param integer $number 必需。 为其返回双倍阶乘的值。 如果 number 不是整数,将被截尾取整 |
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45 | * |
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46 | * @return integer |
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47 | */ |
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48 | public static function factdouble($number) |
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49 | { |
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50 | if ($number == 0) { |
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51 | return 1; |
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52 | } |
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53 | $result = 1; |
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54 | $isEven = $number % 2 == 0; |
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55 | foreach (Arrays::rangeGenerator($isEven ? 2 : 1, (int) $number, 2) as $num) { |
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56 | $result *= $num; |
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57 | } |
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58 | return $result; |
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59 | } |
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60 | |||
61 | /** |
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62 | * 将参数 number 向下舍入(沿绝对值减小的方向)为最接近的 significance 的倍数 |
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63 | * |
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64 | * @param double $number 必需。 要舍入的数值 |
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65 | * @param double $significance 必需。 要舍入到的倍数 |
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66 | * |
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67 | * @return double |
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68 | */ |
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69 | public static function floor($number, $significance = 1) |
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72 | } |
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73 | } |
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74 |