PHP Doku:: Liefert die Summe der Werte in einem Array - function.array-sum.html

Verlauf / Chronik / History: (1) anzeigen

Sie sind hier:
Doku-StartseitePHP-HandbuchFunktionsreferenzVariablen- und typbezogene ErweiterungenArraysArray Funktionenarray_sum

Ein Service von Reinhard Neidl - Webprogrammierung.

Array Funktionen

<<array_splice

array_udiff_assoc>>

array_sum

(PHP 4 >= 4.0.4, PHP 5)

array_sumLiefert die Summe der Werte in einem Array

Beschreibung

number array_sum ( array $array )

array_sum() liefert die Summe der Werte eines Arrays.

Parameter-Liste

array

Das Eingabearray.

Rückgabewerte

Liefert die Summe der Elemente als Integer oder Float.

Changelog

Version Beschreibung
4.2.1 PHP Versionen vor 4.2.1 veränderten das übergebene Array und konvertierten alle String Elemente zu numerischen Werten (was je nach Wert in der Regel 0 als Ergebnis hatte)

Beispiele

Beispiel #1 array_sum()

<?php
$a 
= array(2468);
echo 
"sum(a) = " array_sum($a) . "\n";

$b = array("a"=>1.2"b"=>2.3"c"=>3.4);
echo 
"sum(b) = " array_sum($b) . "\n";
?>

Das oben gezeigte Beispiel erzeugt folgende Ausgabe:

sum(a) = 20
sum(b) = 6.9


21 BenutzerBeiträge:
- Beiträge aktualisieren...
uhehesh at gmail dot com
7.01.2011 11:21
<?php
function avrg()
{
 
$count = func_num_args();
 
$args = func_get_args();
 return (
array_sum($args) / $count);
}
?>

This function calculates average of numbers given as arguments. Examples:
avrg(100, 200, 300) - returns 200.
avrg(5, 6) - returns 5.5.
avrg('foo') - returns 0.
Chris
17.02.2010 17:24
Average array values, ignoring zero values:

<?php
function array_average_nonzero($arr) {
   return
array_sum($arr) / count(array_filter($arr));
}
?>

<?php
$arr
= array(1,2,3,0,0);
echo
array_average_nonzero($arr); // returns 2
echo array_sum($arr) / count($arr); // returns 1.2
?>
hdeus at yahoo dot com
6.10.2008 16:01
Here is how you can multiply two arrays in the form of matrixes using a bit of matrix algebra (M*M).
By calling the function multiplyMatrix, you will be multiplying two sparse matrixes (zeros need not be included in the array for the operation to be performed).

<?php
$M
= array(
0=>array(1=>1,4=>1),
1=>array(2=>1,3=>1),
3=>array(1=>1),
4=>array(5=>1),
5=>array(6=>1)
);

$M1 = multiplyMatrix($M, $M); //multiplying $M by itself

echo '<pre>';print_r($M1);echo '</pre>';

function
multiplyMatrix($M1, $M2)
    {
#Helena F Deus, Oct 06, 2008
##Multiply two matrixes; $M1 and $M2 can be sparse matrixes, the indexes on both should match
       
if(is_file($M1)) {$matrix1 = unserialize(file_get_contents($M1));}
        else
$matrix1 = $M1;
       
           
       
#transpose M2
       
$M2t = transpose($M2);
       
        foreach (
$M2t as $row=>$tmp) {
           
##sum the result of the value in the col multiplied by the value in the vector on the corresponding row
               
               
foreach ($M1 as $row1=>$tmp1) {
                   
                   
$multiply[$row1] = array_rproduct($tmp,$tmp1);
                   
                    if(!
$multiply[$row1]){
                          exit;
                        }
                }
               
                foreach (
$multiply as $row1=>$vals) {
                   
                   
$sum[$row][$row1]=array_sum($vals);
                }
               
        }
   
   
$r=transpose($sum);
   
    return (
$r);
    }

function
transpose($M)
{
foreach (
$M as $row=>$cols) {
           
            foreach (
$cols as $col=>$value) {
                 if(
$value)
                
$Mt[$col][$row]=$value;
            }
        }
       
ksort($Mt);
       
return (
$Mt);           
}

function
array_rproduct($a1, $a2)
{
   
   
    foreach (
$a1 as $line=>$cols) {
       
$a3[$line] = $a1[$line]*$a2[$line];
        foreach (
$a2 as $line2=>$cols2) {
           
$a3[$line2] = $a1[$line2]*$a2[$line2];
        }
    }   
   
ksort($a3);
   
   
    return (
$a3);
   
   
}

?>
c dot heckemueller at befestigungsfuchs dot de
5.09.2008 10:30
<?php
/**
 * sum values in array
 *
 * @param array $arr
 * @param string [optional]$index
 * @return int result
 */
function array_sum_key( $arr, $index = null ){
    if(!
is_array( $arr ) || sizeof( $arr ) < 1){
        return
0;
    }
   
$ret = 0;
    foreach(
$arr as $id => $data ){
        if( isset(
$index )  ){
           
$ret += (isset( $data[$index] )) ? $data[$index] : 0;
        }else{
           
$ret += $data;
        }
    }
    return
$ret;
}
?>

With this function you can choose whether you sum specific keys in a multidim array, or a normalized array. it is designed to not trigger errors if a key is not set.
superman1101
27.08.2008 20:29
To elaborate on djyb2003 at yahoo dot fr. His function can be converted to recursive, but i've made a smaller function to do so:

<?php

 
function array_sum_all($array) {
  
$func = create_function("&\$arr=0,\$key=0","static \$a=0; if(is_int(\$arr)) { \$a+=\$arr; } return \$a;");
  
array_walk_recursive($array,$func);
   return
$func();
 }

$tab = array(
                
0 => array ("val1" => 2,"val2" => 5),
                
1 => array ("val1" => 6,"val2" => 10),
                
"toto" => array ("val1" => 15,"val2" => 50)
                );
var_dump(array_sum_all($tab)); //This will output: int(88);
?>

hope this helps someone
djyb2003 at yahoo dot fr
29.01.2008 15:31
here is a function that can sum values like these :

$tab = array(
                 0 => array ("val1" => 2,"val2" => 5)
                 1 => array ("val1" => 6,"val2" => 10)
                 "toto" => array ("val1" => 15,"val2" => 50)
                );

sum_subarrays_by_key( $tab, "val1" );

the function will sum all values with "val1" key in tab subarrays.

function sum_subarrays_by_key( $tab, $key ) {
       
        $sum = 0;
       
        foreach($tab as $sub_array) {
            $sum += $sub_array[$key];
        }
       
        return $sum;
       
    }

it can be transformed to be recursive and do also all depths possible in an array.

Hope it can be usefull!
Coder
17.08.2007 1:10
A much simpler algorithm for array_sub():

<?php
 
function array_sub($arr) {
    if (!
is_array($arr) || count($arr) == 0) {
      return
false;
    } else {
     
// get first element
     
$base = array_shift($arr);

      return
$base - array_sum($arr);
    }
  }
?>

This will return the exact same results that didikdwi's version.

However, didikdwi's result depends on knowing what the first value is. When this likely bug is removed, the code is:

<?php
 
function array_sub($arr){
   
$temp = array_sum($arr);
    return (
$temp !== false ? -$temp : false );
  }
?>
didikdwi at gmail dot com
18.07.2007 15:48
This is a simple approach to subtract array, both indexed and associative.

  function array_sub($arr) {
    if (!is_array($arr) || count($arr) == 0) {
      return false;
    } else {
      // get first element
      $base = array_shift($arr);

      if (count($arr) == 1) {
        // If only one element, return its
        return $base;
      }

      foreach ($arr as $val) {
        $base -= $val;
      }

      return $base;
    }
  }

// example
$arr1 = array(3, 2, 3);
echo array_sub($arr1);   // Output: -2
$arr2 = array(3.5, 2, 3);
echo array_sub($arr2);   // Output: -1.5
$arr3 = array('a' => 3, 'b' => 2, 'c' => 3);
echo array_sub($arr3);   // Output: -2
herenvardo at gmail dot com
25.11.2006 0:28
I'm not sure if something similar already exists, but I needed it so I made it:
<?php
 
/* Performs a pitagoric sum of the elements in $arr
   The pitagoric sum of a set of values is the square root of
   the sum of the sqare power of each value. So, for a, b, c
   it's sqrt(a^2 + b^2 + c^2) */
  /* If any element of $arr is an array itself, the array_sum
   will be used. Alternatively, the values could be used by
   recursion. Returns the integer part (floor) */
 
function array_pitag_sum($arr) {
    if(
is_array($arr) {
     
$ret = 0;
      foreach(
$arr as $i) {
        if(
is_array($i)) {
         
$s = array_sum($i);
         
$ret += $s*$s;
        } else {
         
$ret += $i*$i;
        }
      }
      return
floor(sqrt($ret));
    } else {
      return
$arr;
    }
  }
?>
Tobias Schlemmer
28.07.2006 8:41
<?php
$array1
= array('1'=>'1','2'=>'2','3'=>'3');
$array2 = array(          '2'=>'1','3'=>'2','4'=>'3');
$array3 = array(                  '3'=>'1','4'=>'2','5'=>'3');
$array  = array_sum_values( $array1, $array2, $array3 );
print_r($array);

/**
 * Sums the values of the arrays be there keys (PHP 4, PHP 5)
 * array array_sum_values ( array array1 [, array array2 [, array ...]] )
 */
function array_sum_values() {
   
$return = array();
   
$intArgs = func_num_args();
   
$arrArgs = func_get_args();
    if(
$intArgs < 1) trigger_error('Warning: Wrong parameter count for array_sum_values()', E_USER_WARNING);
   
    foreach(
$arrArgs as $arrItem) {
        if(!
is_array($arrItem)) trigger_error('Warning: Wrong parameter values for array_sum_values()', E_USER_WARNING);
        foreach(
$arrItem as $k => $v) {
           
$return[$k] += $v;
        }
    }
    return
$return;
}
/* result:
Array
(
    [1] => 1
    [2] => 3
    [3] => 6
    [4] => 5
    [5] => 3
)
*/
?>
jodymickey at yahoo dot com
1.06.2006 17:23
In reference to KageKonjou's array_mode function...

If you only want to know the value in the array that occurs most (and not the number of times it actually occured), you can use this short function.  It also suffers from the same problem in that if there is more than one mode, it will return only one.
<?php
   
function array_mode($array)
    {
        if(!
is_array($array)) return false;
       
asort(array_count_values($array));
        return
array_pop($array);
    }
?>
Moslehi[atsign]Gmail[dot]com
18.03.2006 0:13
A simple example for numeric values :

<?PHP

function array_average($arr){
$sum = array_sum($arr);
$num = sizeof($arr);
echo
$sum/$num;
}

$myarray = array(1,2,3,4);
array_average($myarray); // displays 2.5 as average of 1,2,3,4

?>

[Arash Moslehi]
darianlassan at yahoo dot de
4.11.2005 12:57
function array_avg(&$array)
{
  //**
    returns the average value of all array-values
    or false if no values in array (or not an array)
  **//

  if (!is_array($array) || count($array)==0)
    return false;
  else
    return array_sum($array)/count($array);
} // array_avg()

Please add this function to PHP.
mroach at mroach dot com
27.09.2005 22:06
I ran into a situation where I only wanted to sum elements of an array for certain keys. For that, I wrote this function

<?

function array_sum_by_key()
{
   
$args = func_get_args();
   
   
$arr = array_shift($args);
           
   
$to_sum = is_array($args[0]) ? $args[0] : $args;
   
   
$sum = 0;

    foreach (
$arr as $k=>$v ) {
        if (
in_array($k, $to_sum) ) {
           
$sum += $v;
        }
    }
   
    return
$sum;
}

$arr = array (
   
'dog' => 1,
   
'cat' => 2,
   
'rat' => 4,
   
'mat' => 8,
   
'bat' => 16
);

echo
array_sum_by_key($arr, 'dog', 'mat');

// Result: 9

?>

Alternatively, you can pass the keys to sum as an array

<?

$to_sum
= array('dog', 'bat');

echo
array_sum_by_key($arr, $to_sum);

// Result: 17

?>
KageKonjou at GMail dot com
12.08.2005 18:22
Not sure where else to put this, but I added something that determines the most commonly occuring item in an array.  Known Bugs: It will always return the first value if no mode are found, and the first mode found if more are found of same or lesser count.

<?php
function array_mode($array) {
 
$count = array();
 foreach (
$array as $item) {
 
$count[$item]++;
 }
 
$mostcommon = "";
 
$iter = 0;
 foreach (
$count as $k => $v) {
  if (
$v > $iter) {
  
$mostcommon = $k;
  
$iter = $v;
  }
 }
 return array(
"mode" => $mostcommon, "count" => $count[$mostcommon]);
}
?>
punchto at hotmail dot com
16.03.2005 4:06
Microsoft Excel - SUMIF()

function sumif($array,$criteria,$sum_array){
  if(is_array($array) && is_array($sum_array) && trim($criteria)!= ""){
    $array_count = (count($array) < count($sum_array)) ? count($array):count($sum_array);
    for($i=0;$i<$array_count;$i++){
      if(ereg("^<",$criteria)){
        $value = ereg_replace("^<","",$criteria);
        $result += $array[$i] < $value ? $sum_array[$i]:0;
      }
      elseif(ereg("^>",$criteria)){
        $value = ereg_replace("^>","",$criteria);
        $result += $array[$i] > $value ? $sum_array[$i]:0;
      }
      else{
        $value = $criteria;
        $result += $array[$i] == $value ? $sum_array[$i]:0;
      }
     
    }
    return $result ? $result:0;
  }
}
adam at laural dot com dot au
2.03.2005 1:37
Here's a function to return the sum of a portion of an array:

function array_partial_sum($array, $start, $length){
    $new_array = array_slice($array, $start, $length);
    return array_sum($new_array);
}

$array = array(1, 2, 3, 4, 5);
print array_partial_sum($array, 0, 3);  // prints 6
ncheung at maine dot rr dot com
8.02.2005 3:02
For clarity, array indices containing boolean values such as TRUE and FALSE are added up as though they are 1 and 0 respectively.
mucello NOO SPAM @ weatherimages dOt org
23.10.2003 0:44
If you want to find the AVERAGE of the values in your array, use the sum and count functions together.  For example, let's say your array is $foo and you want the average...

<?php
$average_of_foo
= array_sum($foo) / count($foo);
?>
mcrm at NOTNEEDIT dot freemal dot it
13.08.2003 18:40
Hi people, if someone is searching a function that works also with multimension array, i suggest this :

<?php
function cw_array_count($a) {
  if(!
is_array($a)) return $a;
  foreach(
$a as $key=>$value)
    
$totale += cw_array_count($value);
  return
$totale;
}

$a[0][E][PS][P][a1]=1;
$a[0][E][PS][P][a2]=2;
$a[0][E][PJ][P][a2]=2;
$a[1][E][PS][E][a3]=3;

echo
cw_array_count($a[0]);
// or
echo cw_array_count($a[0][E]);
?>

Bye, Bye.
R.Martina
drverieevil at REMOVEMEasenne dot org
30.07.2003 12:14
If some array elements arent integers, function will change them to integers (content of array will not change) type and then sum them.

Example:
<?php
$foo
[] = "12";
$foo[] = 10;
$foo[] = "bar";
$foo[] = "summer";
echo
array_sum ($foo); //same as echo "22";
?>



PHP Powered Diese Seite bei php.net
The PHP manual text and comments are covered by the Creative Commons Attribution 3.0 License © the PHP Documentation Group - Impressum - mail("TO:Reinhard Neidl",...)