9 Array – II

Hiren Joshi

Multidimensional Array

A multidimensional array is also known as 2-D (two-dimensional) array. It can be thought as array of arrays. A two dimensional array is a tabular array. Following figure helps you to understand 2-D array structure.

To create the above array, the code is

$stud = array(array(1,’Rajan’),

array(2,’Haresh’),

array(3,’Pankaj’));

In the above figure, ID and Name is considered as attributes of array $stud.

To access the element of 2D array, two indexes values are required. The first index value refer to the outer array element and the second index value refer to the inner array element.

To access the first index value of second array element index value , you have to code

echo “ ID: “.$stud[1][0];

This will display ID: 2 on the browser.

This array is considered as nested array also. Here, the nested array inside an outer array is of same size. The size of nested array is same, then such type of array is known as rectangular array. In case the size of nested array is different, then this type of array is known as jagged array.

$jugstud = array(array(1,’Rajan’),

array(2,’Haresh’,’Mehta’),

array(3,’Pankaj’),

array(‘Mehul’));

echo “ ”;

foreach($jugstud as $outkey=>$outval)

{

foreach($outval as $inkey=>$inval)

{

echo ‘<t> ‘. $inval;

//echo ‘<t> ‘. ‘outerkey : ‘. $outkey .’ inkey :’ .$inkey.’ inval: ‘. $inval; // echo ‘<t> ‘.$inkey .’ ‘. $inval; // this will print key as well }

echo “ ”;

}

You can create more than 2D array also in the same way.

To understand the functions let’s write few programs.

range functions in array

range function is used to create an array. The general syntax for range( ) function is range($lo, $hi [, $step]).

The range function create an array with value start from $lo and fill the values to $hi by incement $step. If $step is omitted, then default $step 1.

$nums = range(1,10,1);

foreach($nums as $n)

{

echo “<t> $n “;

}

The above code create an array $nums having values 1,3,5,7,9.

Array_push and Array_pop:

These functions are called stack implementation in array. Stack structure is used LIFO (Last In First Out) approach.

$names = array(“Hiren”,”Vipul”,”Vimal”);

array_push($names,’Devdatt’); // $names is “Hiren”,”Vipul”,”Vimal”, “Devdatt”

echo “ ”;

foreach($names as $name)

{

echo “<t> $name”;

}

echo “ ”;

$last = array_pop($names); //$names is “Hiren”,”Vipul”,”Vimal”

foreach($names as $name)

{

echo “<t> $name”;

}

echo “ $last”; //$last = “Devdatt”

Array_unshift and Array_shift:

Array_push and array_shift functions are used to make queue implementation in array. Queue structure is used FIFO (First In First Out) approach.

//array_unshift

array_unshift($names,”Kalpesh”); //$names is Kalpesh Hiren Vipul Vimal

echo “ ”;

foreach($names as $name)

{

echo “<t> $name”;

}

//array shift

$first = array_shift($names); // $names is Hiren Vipul Vimal

echo “ ”;

foreach($names as $name)

{

echo “<t> $name”;

}

echo “ First : $first”; // First is Kalpesh

Array_count_values function demo

echo “ ”;

$friends = array(“Hiren”,”Vimal”,”Vipul”,”Vimal”,”Devdatt”, “Hiren”,”Kalpesh”); echo “ ”;

foreach($friends as $fr)

{

echo “<t> $fr”;

}

$occurence = array_count_values($friends);

echo “ Hiren occurs $occurence[Hiren] times”;

echo “ Vimal occurs $occurence[Vimal] times”;

echo “ Vipul occurs $occurence[Vipul] times”;

echo “ Devdatt occurs $occurence[Devdatt] times”;

echo “ Kalpesh occurs $occurence[Kalpesh] times”;

Then the output will be

Hiren Vimal Vipul Vimal Devdatt Hiren Kalpesh

Hiren occurs 2 times

Vimal occurs 2 times

Vipul occurs 1 times

Devdatt occurs 1 times

Kalpesh occurs 1 times

Sort function demo

$emp = array(‘Heena’,’Yatin’,’Chirag’,’Siddhi’,’Divya’);

echo “ Before sorting an array ”;

foreach ($emp as $e)

{

echo “<t> $e”;

}

sort($emp);

echo “ After sorting an array ”;

foreach ($emp as $e)

{

echo “<t> $e”;

}

Then the output will be

Before sorting an array

Heena Yatin Chirag Siddhi Divya

After sorting an array

Chirag Divya Heena Siddhi Yatin

rsort demo

rsort($emp);

echo “ Reverse Sorting ”;

foreach ($emp as $e)

{

echo “<t> $e”;

}

Output will be

Reverse Sorting

Yatin Siddhi Heena Divya Chirag

ksort demo

<?php

$milk = array(‘gold’=>24,’diamond’=>26,’taza’=>20,’shakti’=>22);

echo “ Before sorting an array ”;

foreach ($milk as $m=>$v)

{

echo “ $m price is Rs. $v”;

}

ksort($milk);

echo “ After ksort an array: “;

foreach ($milk as $m=>$v)

{

echo “ $m price is Rs. $v”;

}

Output will be

Before sorting an array

gold price is Rs. 24

diamond price is Rs. 26

taza price is Rs. 20

shakti price is Rs. 22

After ksort an array:

diamond price is Rs. 26

gold price is Rs. 24

shakti price is Rs. 22

taza price is Rs. 20

Shuffle function example.

<?php

//Shuffle demo

echo “ ”;

$values = array(‘2′,’3′,’4′,’5′,’6′,’7′,’8′,’9′,’10’,’J’,’Q’,’K’,’A’); $types = array(‘C’,’D’,’H’,’S’);

echo ‘ The playing card are ’;

$cards = array();

foreach($types as $t)

{

foreach($values as $v)

{

$cards[] = $t.$v;

}

foreach($cards as $card)

{

echo “<t> $card”;

}

echo ‘ After shuffle the 5 cards are ‘;

shuffle($cards);

$hand = array();

for($i =0; $i<5;$i++)

{

$hand[] = array_shift($cards);

}

echo implode(‘ ‘,$hand);

When you execute the function, then the Output can be

The playing card are

C2 C3 C4 C5 C6 C7 C8 C9 C10 CJ CQ CK CA D2 D3 D4 D5 D6 D7 D8 D9 D10 DJ DQ DK DA H2 H3 H4 H5 H6

H7 H8 H9 H10 HJ HQ HK HA S2 S3 S4 S5 S6 S7 S8 S9 S10 SJ SQ SK SA

After shuffle the 5 cards are

S7 H4 D3 CJ HQ

you can view video on Array – II

References:

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