It is an array based PHP program. A matrix is a two-dimensional array and subtraction is an operation done between 2 matrices.
NOTE: To do subtraction between matrices the order of both matrices should be the same.
We require knowledge of the following topics to understand the program clearly. So, let's have a look at them.
To find the subtraction of 2 two-dimensional arrays first we have to find the number of rows and columns in the array and subtract the corresponding index together. For example, If the arrays are
2 5 8 1 3 1
a[] = 6 2 5 b[] = 3 1 1
4 5 6 3 1 2
then the result will be:
1 2 7
3 1 4
1 4 4
In this program, we are using the static values which are initialized in the code itself. First, we have to initialize 2 two-dimensional arrays arr1 and arr2, we have to assign the number of rows and columns into the variable row and col using the built-in function count()
. Then we have to create an empty array sub_arr[ ] to store the subtracted value of array arr1[ ] and arr2[ ]. Then using a nested for loop
, until the condition 'i < row' becomes false in 1st loop and until the condition 'j < col' becomes false in 2nd loop assign the calculated difference of arr1[i][j] - arr2[i][j] into the array sub_arr[i][j]. After subtraction print the elements of the two-dimensional array sub_arr[ ][ ] using for loop
STEP 1: Initialize 2 two-dimensional arrays arr1[ ] and arr2[ ]
STEP 2: Assign the number of rows and columns into the variable row and col using the built-in function count()
STEP 3: Print the elements in the array arr1[ ] and arr2 []
STEP 4: Create an empty array sub_arr[ ] to store the subtract of array arr1[ ] and arr2[ ]
STEP 5: Assign the value 0 into the variable i and perform the step 6 until the condition 'i < row' becomes false and increment the value of variable i in every iteration
STEP 6: Assign the value 0 into the variable j and perform the sub-step until the condition 'j < col' becomes false and increment the value of variable j in every iteration
Step 7: Print the elements of the two-dimensional array sub_arr[ ][ ] using for loop
<?php
$arr1 = array(
array(6, 7, 7),
array(9, 5, 2),
array(8, 4, 8)
);
$arr2 = array(
array(4, 6, 5),
array(3, 2, 1),
array(6, 3, 3)
);
$row = count($arr1);
$col = count($arr1[0]);
echo "First matrix: \n";
for ($i = 0; $i < $row; $i++) {
for ($j = 0; $j < $col; $j++) {
echo $arr1[$i][$j] . " ";
}
echo "\n";
}
echo "Second matrix: \n";
for ($i = 0; $i < $row; $i++) {
for ($j = 0; $j < $col; $j++) {
echo $arr2[$i][$j] . " ";
}
echo "\n";
}
$sub_arr = array();
for ($i = 0; $i < $row; $i++) {
for ($j = 0; $j < $col; $j++) {
$sub_arr[$i][$j] = $arr1[$i][$j] - $arr2[$i][$j];
}
}
echo "Subtraction of two matrices: \n";
for ($i = 0; $i < $row; $i++) {
for ($j = 0; $j < $col; $j++) {
echo $sub_arr[$i][$j] . " ";
}
echo "\n";
}
?>
First matrix: 6 7 7 9 5 2 8 4 8 Second matrix: 4 6 5 3 2 1 6 3 3 Subtraction of two matrices: 2 1 2 6 3 1 2 1 5