matrices definistion

Links for php scripts

Moderators: macek, egami, gesf

User avatar
Posts: 2272
Joined: Sat Jul 05, 2003 1:18 pm
Location: A bunk in the back

Postby swirlee » Sun Nov 16, 2003 12:26 am

Interesting problem. First of all, by your example I'm not sure how you intend to collect the data. I'd suppose you'd have a grid of <input type="text" name="matrix[m][n]"> boxes, where m and n are the column and row, respectively. Since you're using multidimensional arrays (the PHP equivalent of a matrix), so your <input>s would have the following names:

Code: Select all

matrix_a[0][0]  matrix_a[1][0]  matrix_a[2][0]  matrix_a[3][0]
matrix_a[0][1]  matrix_a[1][1]  matrix_a[2][1]  matrix_a[3][1]
matrix_a[0][2]  matrix_a[1][2]  matrix_a[2][2]  matrix_a[3][2]

...and so on. Then you'd have a second, similar grid of <input>s for the n x k matrix.

With me so far? Since m, n, and k are unknown (I'm assuming), you'd just have PHP generate the <input> grid with a nested for() loop, something like this:

Code: Select all

<form method="GET" action="script.php">
$m_max = 3; // the number of columns in the m x n matrix
$n_max = 2; // the number of rows for m x n, cols for n x k
$k_max = 4; // you get the picture..

// generate the m x n <input> grid
for($m = 0; $m < $m_max; $m++) {
   for($n = 0; $n < $n_max; $n++) {
      echo '<input type="text" name="matrix_a[' . $m . '][' . $n . ']">';
   echo "<br/>\n";

echo "<br/>\n";

// generate the n x k grid
for($n = 0; $n < $n_max; $n++) {
   for($k = 0; $k < $k_max; $k++) {
      echo '<input type="text" name="matrix_b[' . $n . '][' . $k . ']">';
   echo "<br/>\n";
<input type="submit">

There, now you have two nice grids of text input fields. The first (m x n) will dump into a multidimensional array called $matrix_a, and the second (n x k) into $matrix_b.

Now's where it gets interesting. You have to do some math. Either you can read up on matrix multiplication and write your own implementation, or (and this is what I recommend), you can just use someone else's. PEAR has a good Math component, or you could try the PHP Math Library Project, or, if all else fails, just Google it. Have fun!

Return to “PHP Scripts”

Who is online

Users browsing this forum: No registered users and 1 guest