How to create dynamic matrix in php? - php

Question

I have this table "city" in my database:
|id |id_city_a |id_city_b|distance|
|1 |1 | 1 | 0 |
|2 |1 | 2 | 8 |
|3 |1 | 3 | 6 |
|4 |2 | 1 | 8 |
|5 |2 | 2 | 0 |
|6 |2 | 3 | 9 |
|7 |3 | 1 | 6 |
|8 |3 | 2 | 9 |
|9 |3 | 3 | 0 |
I want the end result to be in a matrix, such as:
| | 1 | 2 | 3 |
| 1 | 0 | 8 | 6 |
| 2 | 8 | 0 | 9 |
| 3 | 6 | 9 | 0 |
This is my code :
function random()
{
include('config/koneksi.php');
$result = mysql_query("select * from temp_hasil");
$n =mysql_num_rows(mysql_query("SELECT * FROM temp_hasil"));
for ($i = 1; $i <= $n; $i++)
{
for ($j = 1; $j <= $n; $j++)
{
$rows = mysql_fetch_array($result);
$this->table[$i][$j] = $i == $j ? INF : $rows['id'];
}
}
}
function __toString()
{
$str = '<table class="table table-bordered" id="tableInput"> <tbody>';
$str .= '<tr><td></td>';
foreach ($this->table as $rowName => $row)
{
$str .= "<td>$rowName</td>";
}
$str .= '</tr>';
foreach ($this->table as $rowName => $row)
{
$str .= "<tr><td>$rowName</td>";
foreach ($row as $columnName => $value)
{
$str .= "<td>";
$str .=
'<input class="form-control" type="text" value="' . $value . '" name="table[' . $rowName . '][' .
$columnName . ']" requied' . ($columnName == $rowName ? ' disabled' : '') . '>';
$str .= "</td>";
}
$str .= '</tr>';
}
$str .= '</tbody></table>';
return $str;
}
}
$str .= '</tr>';
foreach ($this->table as $rowName => $row)
{
$str .= "<tr><td>$rowName</td>";
foreach ($row as $columnName => $value)
{
$str .= "<td>";
$str .=
'<input class="form-control" type="text" value="' . $value . '" name="table[' . $rowName . '][' .
$columnName . ']" requied' . ($columnName == $rowName ? ' disabled' : '') . '>';
$str .= "</td>";
}
$str .= '</tr>';
}
$str .= '</tbody></table>';
return $str;
}
`
How do I code it in php? please help me.

Answer 1

Make city_a index completely different from city_b index so it is easy to check.
// generate a two-dimensional matrix in here
$distMatrix = array();
foreach($tableRows as $cityDist) {
$from = $cityDist['id_city_a'];
$to = $cityDist['id_city_b'];
$dist = $cityDist['distance'];
$distMatrix[$from][$to] = $dist;
}
Display as an HTML Table...
echo '<table border="1">';
echo '<tr>';
echo '<td>', '#', '</td>';
foreach(array_keys(current($distMatrix)) as $city_b) { // city_b headings
echo '<td>', $city_b ,'</td>';
}
echo '</tr>';
foreach(array_keys($distMatrix) as $city_a) { // need the city_a as row index
echo '<tr>';
echo '<td>', $city_a, '</td>'; // city_a ad
foreach(array_keys($distMatrix[$city_a]) as $city_b) { // need the city_b as column index
echo '<td>', $distMatrix[$city_a][$city_b], '</td>'; // distance from the matrix;
}
echo '</tr>';
}
echo '</table>';
Test data - used data from #ashkufaraz
// changed the city ids so we can easily see city_a and city_b
$tableRows[0]=array("id"=>1, "id_city_a"=>1, "id_city_b"=>11, "distance"=>0);
$tableRows[1]=array("id"=>2, "id_city_a"=>1, "id_city_b"=>12, "distance"=>8);
$tableRows[2]=array("id"=>3, "id_city_a"=>1, "id_city_b"=>13, "distance"=>6);
$tableRows[3]=array("id"=>4, "id_city_a"=>2, "id_city_b"=>11, "distance"=>8);
$tableRows[4]=array("id"=>5, "id_city_a"=>2, "id_city_b"=>12, "distance"=>0);
$tableRows[5]=array("id"=>6, "id_city_a"=>2, "id_city_b"=>13, "distance"=>9);
$tableRows[6]=array("id"=>7, "id_city_a"=>3, "id_city_b"=>11, "distance"=>6);
$tableRows[7]=array("id"=>8, "id_city_a"=>3, "id_city_b"=>12, "distance"=>9);
$tableRows[8]=array("id"=>9, "id_city_a"=>3, "id_city_b"=>13, "distance"=>0);
Output:
# 11 12 13
1 0 8 6
2 8 0 9
3 6 9 0

Answer 2

try like this
Online Demo
$tableRows[0]=array("id"=>1,"id_city_a"=>1,"id_city_b"=>1,"distance"=>0);
$tableRows[1]=array("id"=>2,"id_city_a"=>1,"id_city_b"=>2,"distance"=>8);
$tableRows[2]=array("id"=>3,"id_city_a"=>1,"id_city_b"=>3,"distance"=>6);
$tableRows[3]=array("id"=>4,"id_city_a"=>2,"id_city_b"=>1,"distance"=>8);
$tableRows[4]=array("id"=>5,"id_city_a"=>2,"id_city_b"=>2,"distance"=>0);
$tableRows[5]=array("id"=>6,"id_city_a"=>2,"id_city_b"=>3,"distance"=>9);
$tableRows[6]=array("id"=>7,"id_city_a"=>3,"id_city_b"=>1,"distance"=>6);
$tableRows[7]=array("id"=>8,"id_city_a"=>3,"id_city_b"=>2,"distance"=>9);
$tableRows[8]=array("id"=>9,"id_city_a"=>3,"id_city_b"=>3,"distance"=>0);
$counter=0;
$result=array();
foreach($tableRows as $tableRow)
{
$result[$tableRow["id_city_a"]][$tableRow["id_city_b"]]=array("id_city_a"=>$tableRow["id_city_a"],"id_city_b"=>$tableRow["id_city_b"],"distance"=>$tableRow["distance"] );
}
now in $result[cityA][cityB]=distance
get unique_id_city_a for column
$unique_id_city_a = array_unique(array_map(function ($i) { return $i['id_city_a']; }, $tableRows));
echo "\t";
foreach($unique_id_city_a as $R)
{
echo $R."\t";
}
echo "\n";
get unique_id_city_b for rows
$unique_id_city_b = array_unique(array_map(function ($i) { return $i['id_city_b']; }, $tableRows));
foreach($result as $R1)
{
echo $unique_id_city_b[$counter++]."\t";
foreach($R1 as $R2)
{
echo $R2["distance"]."\t";
}
echo "\n";
}