所以当我运行这段代码时，我得到了很多这样的错误。我打算放弃，只使用PHP内置的排序函数。但我希望有人能看到这里的问题。请参阅下面的代码。如果你看不清，先说声抱歉。
数组输入与print_r输出完全符合预期，但实际的排序算法无法工作，无论我尝试什么。底部的两个注释函数用于不同的试验。
<?php
//this function will pull a string from a txt file and pass characters to an array
function strToArray($file){
if ($handle = fopen($file, 'r')){
$string = fread($handle, filesize($file));
fclose($handle);
}
$strArray = str_split(preg_replace('/'s+/', '', $string)); //regex in preg_replace gets rid of all whitespaces; str_split converts string to array
$arrLen = array_count_values($strArray);
return $arrLen;
}
$arrayWithVal = strToArray("filetest.txt"); //intermediary to pass into next function
print_r($arrayWithVal); //see what I have so far
echo "<hr />";
$newArray = $arrayWithVal;
for ($i = 1; $i < count($newArray); $i++){
for ($j = $i-1; $j >= 0; $j--){
if ($newArray[$j] > $newArray[$j+1]){ //if value on left is bigger than current value
$oldValue = $newArray[$j+1];
$newArray[$j+1] = $newArray[$j];
$newArray[$j] = $oldValue;
//return $newArray;
}
else {
break; //if value on left is smaller, skip to next position
}
}
}
print_r($newArray); //END
/*
function insertionSort($array){
$newArray=$arrayWithVal;
for($j=1; $j < count($newArray); $j++){
$temp = $newArray[$j];
$i = $j;
while(($i >= 0) && ($newArray[$i-1] > $temp)){
$newArray[$i] = $newArray[$i-1];
$i--;
}
$newArray[$i] = $temp;
}
return $array;
}
*/
/*
function insertionSort($arrData){
for ($i=1;$i<count($arrData);$i++){
for ($j=$i-1;$j>=0;$j--){
if ($arrData[$j]>$arrData[$j+1]){ //if value on left is bigger than current value
$oldValue = $arrData[$j+1];
$arrData[$j+1] = $arrData[$j];
$arrData[$j] = $oldValue;
}
else {
break; //if value on left is smaller, skip to next position
}
}
}
return $arrData;
}
*/
?>
EDIT:我还应该提到，在它返回错误之后，它打印与第一个print_r输出相同的数组。
您正在使用array_count_values($strArray)函数，该函数将返回一个数组，使用$strArray的值作为键，并使用$strArray中的频率作为值。
所以对于例子:$arrayWithVal将为:
array('some_word'=>3,'other_word'=>4);
你正在复制这个数组到$newArray，然后你试图访问$newArray与数字索引:$newArray[$j+1]，而$newArray是一个关联数组。
这就是为什么你得到未定义的偏移错误。
你的问题的确切工作代码可以是:
//this function will pull a string from a txt file and pass characters to an array
function strToArray($file){
if ($handle = fopen($file, 'r')){
$string = fread($handle, filesize($file));
fclose($handle);
}
$strArray = str_split(preg_replace('/'s+/', '', $string)); //regex in preg_replace gets rid of all whitespaces; str_split converts string to array
$arrLen = array_count_values($strArray);
return $arrLen;
}
$arrayWithVal = strToArray("filetest.txt"); //intermediary to pass into next function
print_r($arrayWithVal); //see what I have so far
$newArray = $arrayWithVal;
$test = array();
foreach($newArray as $v){
$test[] = $v;
}
for ($i = 1; $i < count($test); $i++){
for ($j = $i-1; $j >= 0; $j--){
if ($test[$j] > $test[$j+1]){ //if value on left is bigger than current value
$oldValue = $test[$j+1];
$test[$j+1] = $test[$j];
$test[$j] = $oldValue;
//return $newArray;
}
else {
break; //if value on left is smaller, skip to next position
}
}
}
$result = array();
foreach($test as $k => $v){
$keys_array = array_keys($newArray, $v);
foreach($keys_array as $key){
$result[$key] = $v;
}
}
print_r($result);// to see $result array
如果你的$newArray是:
Array
(
[some] => 4
[r] => 3
[w] => 6
[t] => 1
[a] => 8
[hell] => 4
)
$result数组将:
Array
(
[t] => 1
[r] => 3
[some] => 4
[hell] => 4
[w] => 6
[a] => 8
)
如果你正在学习PHP，这是一个很好的方法，否则你应该只使用内置PHP函数，以获得更好的时间性能。
希望对大家有所帮助