Converts a list of possible parameters into a stack of permutations.
Takes a list of parameters containing possible values, and converts all of them into a list of items containing every possible permutation.
Example:
$parameters = array(
'one' => array(
0,
1,
),
'two' => array(
2,
3,
),
);
$permutations = TestBase::generatePermutations($parameters);
// Result:
$permutations == array(
array(
'one' => 0,
'two' => 2,
),
array(
'one' => 1,
'two' => 2,
),
array(
'one' => 0,
'two' => 3,
),
array(
'one' => 1,
'two' => 3,
),
);
$parameters: An associative array of parameters, keyed by parameter name, and whose values are arrays of parameter values.
A list of permutations, which is an array of arrays. Each inner array contains the full list of parameters that have been passed, but with a single value only.
public static function generatePermutations($parameters) {
$all_permutations = array(
array(),
);
foreach ($parameters as $parameter => $values) {
$new_permutations = array();
// Iterate over all values of the parameter.
foreach ($values as $value) {
// Iterate over all existing permutations.
foreach ($all_permutations as $permutation) {
// Add the new parameter value to existing permutations.
$new_permutations[] = $permutation + array(
$parameter => $value,
);
}
}
// Replace the old permutations with the new permutations.
$all_permutations = $new_permutations;
}
return $all_permutations;
}