php获取指定范围内最接近数的方法

// Returns the next higher or lower number function NextRelatedNumber($number, $range){ $r = $number % $range; $f = $number - $r; $b = round($r / $range, 0); return ($b == 1) ? $f + $range : $f; } // Returns the next higher number function NextHigherNumber($number, $range){ $r = $number % $range; $f = $number - $r; $b = ceil($r / $range); return ($b == 1) ? $f + $range : $f; } // Returns the next lower number function NextLowerNumber($number, $range){ $r = $number % $range; $f = $number - $r; $b = floor($r / $range); return ($b == 1) ? $f + $range : $f; } // Returns the next related number from an array function NextNumberArray($Number, $NumberRangeArray){ $w = 0; $c = -1; $abstand = 0; $l = count($NumberRangeArray); for($pos=0; $pos < $l; $pos++){ $n = $NumberRangeArray[$pos]; $abstand = ($n < $Number) ? $Number - $n : $n - $Number; if ($c == -1){ $c = $abstand; continue; } else if ($abstand < $c){ $c = $abstand; $w = $pos; } } return $NumberRangeArray[$w]; } // Examples // -------- // 0 10 20 30 40 50 ... print 'NextRelatedNumber: '; print NextRelatedNumber(44, 10) . "\n"; // returns --> 40 // 0 20 40 60 80 100 ... print 'NextHigherNumber: '; print NextHigherNumber(41, 20) . "\n"; // returns --> 60 // 0 5 10 15 20 25 30 35 ... print 'NextLowerNumber: '; print NextLowerNumber(57, 5) . "\n"; // returns --> 55 // Example with Array print 'NextNumberArray: '; print NextNumberArray(45, array(3, 8, 19, 34, 56, 89)) . "\n"; // returns --> 34 // (45 is between 34 and 56 but 34 is the next)