Question

Possible Duplicate:
Retrieving numeric characters from a string

I have a string like this –

[ [ -2, 1/2 ], // 1/2 represents one half

I want to retrieve the numeric characters and put them into an array that will end up looking like this:

array(
  [0] => -2,
  [1] => 1/2
)

What is the best way of doing this?

A more thorough example –

[ [ -2, 1/2, 4, 8 ],
  [ 5,  1/2, 1, -4/3 ],
  [ -2, 7/2, 4, 4 ],
  [ -2, 1/2, -3, 2 ] ]

I am going through this matrix line by line and I want to extract the numbers into an array for each line.

This question is very similar to a question I asked before – Retrieving numeric characters from a string

The difference is that there are no decimal points in the numbers. Instead non-integers are represented as fractions.

Answer 1

Try to deal with preg syntax. Your preg expression is simple: /(-?\d+(?:\/\d+)?)/.

preg_match_all( '/(-?\d+(?:\/\d+)?)/', $string, $matches);

// given :
$str = '[ [ -2, 1/2, 4, 8 ],
  [ 5,  1/2, 1, -4/3 ],
  [ -2, 7/2, 4, 4 ],
  [ -2, 1/2, -3, 2 ] ]';

// outut :
$matches = array (
  0 => 
  array (
    0 => '-2',
    1 => '1/2',
    2 => '4',
    3 => '8',
    4 => '5',
    5 => '1/2',
    6 => '1',
    7 => '-4/3',
    8 => '-2',
    9 => '7/2',
    10 => '4',
    11 => '4',
    12 => '-2',
    13 => '1/2',
    14 => '-3',
    15 => '2',
  ),
  1 => 
  array (
    0 => '-2',
    1 => '1/2',
    2 => '4',
    3 => '8',
    4 => '5',
    5 => '1/2',
    6 => '1',
    7 => '-4/3',
    8 => '-2',
    9 => '7/2',
    10 => '4',
    11 => '4',
    12 => '-2',
    13 => '1/2',
    14 => '-3',
    15 => '2',
  ),
);