我有一个array。它有正值、负值和零值。现在我想计算那些正、负和零值的数量，然后用数组的数量除以每组。我尝试过以下方式：
<?php
$arr = ['-4','3','-9','0','4','1'];
$countNum = count($arr);
//print_r($countNum);
foreach ($arr as $key => $value) {
if ($value<0) {
continue;
}elseif($value==0){
continue;
}else{
$result = $value/$countNum;
echo $result."</br>";
}
}
?>
输出为：
0.5
0.66666666666667
0.16666666666667
但我想要并且应该是：
for positive, 3/6=0.500000
for negative, 2/6=0.333333
for zero, 1/6=0.166667
试试这个代码。
<?php
$zero = '0';
$positive = '0';
$negative = '0';
$arr = array('-4','3','-9','0','4','1');
$total = count($arr);
foreach ($arr as $num){
if ($num > '0'){
$positive++;
} else if ($num < '0'){
$negative++;
} else {
$zero++;
}
}
echo "Positive: ".$positive/$total;
echo '<br />';
echo "Negative: ".$negative/$total;
echo '<br />';
echo "Zero: ".$zero/$total;
?>
<?php
$arr = ['-4','3','-9','0','4','1'];
$countNum = count($arr);
$neg_count = $pos_count = $zero_count = 0;
//print_r($countNum);
foreach ($arr as $key => $value) {
if ($value<0) {
$neg_count++;
}elseif($value==0){
$zero_count++;
}else{
$pos_count++;
}
}
echo 'for Negative : '.$neg_count/$countNum;
echo '<br>for Positive : '.$pos_count/$countNum;
echo '<br>for Zero : '.$zero_count/$countNum;
使用具有正值、负值和零值的命名键的数组的简短解决方案：
$arr = ['-4','3','-9','0','4','1'];
$total = count($arr);
$numbers = ["negatives" => 0, "positives" => 0, "zeros" => 0];
foreach ($arr as $v) {
$v = (int) $v;
$numbers[($v == 0)? 'zeros' : (($v < 0)? 'negatives': 'positives')]++;
}
echo "for positive: ". "{$numbers["positives"]}/$total=" .$numbers["positives"]/$total .PHP_EOL;
echo "for negative: ". "{$numbers["negatives"]}/$total=" .$numbers["negatives"]/$total .PHP_EOL;
echo "for zero: ". "{$numbers["zeros"]}/$total=" .$numbers["zeros"]/$total .PHP_EOL;
输出：
for positive: 3/6=0.5
for negative: 2/6=0.33333333333333
for zero: 1/6=0.16666666666667
如果要格式化输出值，请使用number_format函数。number_format($positive/$total, 6, '.', '');
这里有一种稍微不同的方法：
$arr = ['-4','3','-9','0','4','1'];
$countNum = count($arr);
// Positives = ['3', '4', '1']
$positives = array_filter($arr, function ($v) {
return $v > 0;
});
// 3/6 = 0.5
echo count($positives) / $countNum;
// Zeros = ['0']
$zeros = array_filter($arr, function ($v) {
return $v == 0;
});
// 1/6 = 0.1666666667
echo count($zeros) / $countNum;
// Negatives = ['-4', '-9']
$negatives = array_filter($arr, function ($v) {
return $v < 0;
});
// 2/6 = 0.333333333
echo count($negatives) / $countNum;
<?php
$arr = ['-4','3','-9','0','4','1'];
$countNum = count($arr);
$positives = $negatives = $zeros = 0;
$arrValues = array(
"zeros" => 0,
"positives" => 0,
"negatives" => 0,
);
foreach ($arr as $key => $value) {
if ($value == 0) { //ZEROS
$zeros++;
$arrValues['zeros'] = $zeros;
}else if ($value < 0) { //NEGATIVES
$negatives++;
$arrValues['negatives'] = $negatives;
}else{ //POSITIVES
$positives++;
$arrValues['positives'] = $positives;
}
}
$arrValues["positives"] = doubleval($arrValues["positives"])/$countNum;
$arrValues["negatives"] = doubleval($arrValues["negatives"])/$countNum;
$arrValues["zeros"] = doubleval($arrValues["zeros"])/$countNum;
var_dump($arrValues);