PHP切割整数工具，类似微信红包金额分配

compor地址：

github地址：

主要代码：numberslicing.php

思路：将数字按精度放大倍数，比如切割数字1，切割的份数是10，精度是0.01，则将1放大100 x 10倍，然后再来对加了1000倍权重后的值进行切割。切割完成之后，再将权重去除，保证总值是1。

<?phpnamespace werben\tools;u exception;class numberslicing {    /**     * 精确小数点，舍弃最后一位之后的数据（非四舍五入）     * floor with precision     * @param $number 要精确的数     * @param 普通话手抄报简单字少$precision 精度，比如保留到0.01，则该值为2     * @return float|int     */    public static function floorwithprecision($nu河南一本大学mber, $precision) {        $power = pow(10, $precision);        $ret = floor($number * $power) * 1.0 / $power ;        return $ret;    }    /**     * 精确小数点，按四舍五入保留最后一位     * round with precision     * @param $number 要精确的数     * @param $precision 精度，比如保留到0.01，则该值为2     * @return float|int     */    public static function roundwithprecision($number, $precision) {        $power = pow(10, $precision);        $ret = round($number * $power) * 1.0 / $power ;        return $ret;    }    /**     * 将数把权重放大，比如1，要按精度0.0001分配，则先将1乘以10000然后再来分配     * random the sum weights   加上权重之后，整个要切割的数的权重总值     * @param $weight_items 用来保留，随机分配的权重值     * @param $count    要切割的份数     * @param int $each_weight 加上权重之后，每一份平均的权重值     * @param int $min_weight   加上权重之后，最小额度的值     * @return float|int     */    public static function weightslicing(&$weight_items, $count, $each_weight = 10, $min_weight = 3)    {        $already_count = count($weight_items);        $cur_random_full_total = ($already_count + 1) * $each_weight;        $already_random_real_total = 0;        foreach ($weight_items as $value) {            $already_random_real_total += $value;        }        $cur_random_rest = $cur_random_full_total - $already_random_real_total;        if ($already_count == $count - 1) {            $cur_random_rate = $cur_random_rest;        } el {            $cur_random_rate_max = $cur_random_rest + $each_weight - $min_weight * 2;            $cur_random_rate = $min_weight + mt_rand(0, $cur_random_rate_max);        }        $weight_items[] = $cur_random_rate;        return $cur_random_rate;    }    /**     * slicing the number     * @param int $number     * @param int $size     * @param float $precision     * @param float $min     * @return array     * @throws exception     */    public static function numberslicing($number, $size, $precision = 0.01, $min = 0.01) {        if ($number * 1.0 / $size <= $min) {            throw new exception('min number is bigger than the average value!');        }        if ($precision >中学生心理测试题; 1) {            throw new exception('precision can\'t bigger than 1!');        }        if ($min < $precision) {            throw new exception('precision can\'t bigger than min!');        }        $weight_items = [];        $items = [];        //不加权重情况下，每一份的平均值        $each_weight = intval($number / $size);        if ($precision < 1) {            //如果精度是小数            if ($each_weight > 1) {                //如果平均值大于1，则最小额度则直接用min就可以了                //每一份的平均值乘以权重的值，比如精度为0.01，则每一份的平均值要乘以权重（100）                $each_weight = intval((1 / $precision) * $number / $size);                //最小数值也要乘以权重                $min_weight = intval(1 / $precision) * $min;            } el {                //如果平均值小于1，需要将平均值也乘以权重                $each_weight = 古琴音乐intval(1 / $precision);                $min_weight = $each_weight * $size * $min / $number;            }            $precision_num = log10(1 / $precision);        } el {            //如果精度是整数(1)            $min_weight = $min;            $precision_num = 0;        }        $sum_item_number = 0.0;        $sum_weight = 0.0;        //先将整个数，随机按最小额度分配        for ($i = 0; $i < $size; $i++) {            $cur_weight = lf::weightslicing($weight_items, $size, $each_weight, $min_weight);            //将权重去除，换算回原先的比例            $rate = ($number * $cur_weight * 1.00) / ($size * $each_weight);            $rate = lf::floorwithprecision($rate, $precision_num);            $sum_item_number += $rate;            $sum_weight += $cur_weight;            $items[] = $rate;        }        //由于误差，随机分配后，还会遗留一些数没有完全分配完，则将剩下的数随机分配        if ($precision_num != 0) {            //如果是切割成小数            $rest = $number - $sum_item_number;            while ($rest - 0.00 > php_float_min) {                if ($rest / $min >= 1.0) {                    //剩余的数大于min最小额度，则将每份最小额度随机分配                    $random_index = mt_rand(0, $size - 1);                    $items[$random_index] = lf::roundwithprecision($items[$random_index] + $min, $precision_num);                    $sum_item_number = lf::roundwithprecision($sum_item_number + $min, $precision_num);                    $rest = lf::roundwithprecision($number - $sum_item_number, $precision_num);                } el {                    //剩余的数小于min最小额度，则将这最后的未分配的数随机分配                    $random_index = mt_rand(0, $size - 1);                    $items[$random_index] = lf::roundwithprecision($items[$random_index] + $number - $sum_item_number, $precision_num);                    $sum_item_number = $number;                    $rest = $number - $sum_item_number;                }            }        } el {            //如果是切割成整数            $rest = $number - $sum_item_number;            while ($rest > 0) {                if ($rest / $min >= 1) {                    $random_index = mt_rand(0, $size - 1);                    $items[$random_index] += $min;                    $sum_item_number += $min;                    $rest = $number - $sum_item_number;                } el {                    $random_index = mt_rand(0, $size - 1);                    $items[$random_index] += $rest;                    $sum_item_number += $rest;                    $rest = $number - $sum_item_number;                }            }        }        return $items;    }}

　　测试代码：

u werben\tools\numberslicing;function testintslicing2intone() {    $precision = 1; //精确度 eg: 1, 0.1, 0.01, 0.01    $size = 10;         //切割的份数，the size of the number to slicing    $min = 3;        //最小额度，最小额度必须大于最小精度，min amount eg: 3, 0.23, 0.05, 0.008    $number = 100;      //要切割的数字，the number    $items = numberslicing::numberslicing($number, $size, $precision, $min);    $sum = 0.0;    $ret_min = $number;    foreach ($items as $value) {        $sum += $value;        if ($ret_min > $value) {            $ret_min = $value;        }    }    $count = count($items);    echo "count: $count, sum: $sum, ret_min: $ret_min\n";    echo "items : ". json_encode($items) ."\n";}function testintslicing2inttwo() {    $precision = 1; //精确度 eg: 1, 0.1, 0.01, 0.01    $size = 30;         //切割的份数，the size of the number to slicing    $min = 18666;        //最小额度，最小额度必须大于最小精度，min amount eg: 3, 0.23, 0.05, 0.008    $number = 800000;      //要切割的数字，the number    $items = numberslicing::numberslicing($number, $size, $precision, $min);    $sum = 0.0;    $ret_min = $number;    foreach ($items as $value) {        $sum += $value;        if ($ret_min > $value) {            $ret_min = $value;        }    }    $count = count($items);    echo "count: $count, sum: $sum, ret_min: $ret_min\n";    echo "items : ". json_encode($items航天员什么时候返回地面) ."\n";}function testintslicing2floatone() {    $precision = 0.01; //精确度 eg: 1, 0.1, 0.01, 0.01    $size = 1000;         //切割的份数，the size of the number to slicing    $min = 0.05;        //最小额度，最小额度必须大于最小精度，min amount eg: 3, 0.23, 0.05, 0.008    $number = 100;      //要切割的数字，the number    $items = numberslicing::numberslicing($number, $size, $precision, $min);    $sum = 0.0;    $ret_min = $number;    foreach ($items as $key => $value) {        $sum += $value;        if ($ret_min > $value) {            $ret_min = $value;        }    }    $count = count($items);    echo "count: $count, sum: $sum, ret_min: $ret_min\n";    echo "items: ". json_encode($items) ."\n";}function testintslicing2floattwo() {    $precision = 0.00001; //精确度 eg: 1, 0.1, 0.01, 0.01    $size = 1000;         //切割的份数，the size of the number to slicing    $min = 0.00005;        //最小额度，最小额度必须大于最小精度，min amount eg: 3, 0.23, 0.05, 0.008    $number = 5;      //要切割的数字，the number    $items = numberslicing::numberslicing($number, $size, $precision, $min);    $sum = 0.0;    $ret_min = $number;    foreach ($items as $key => $value) {        $sum += $value;        if ($ret_min > $value) {            $ret_min = $value;        }    }    $count = count($items);    echo "count: $count, sum: $sum, ret_min: $ret_min\n";    echo "items: ". json_encode($items) ."\n";}