converting string into multidimensional array

[knight06]

I'd like to convert this string:\[code\]$credit_packages_string = "300,0.25|1000,0.24|3000,0.22|4000,0.20|5000,0.18|6000,0.16|7000,0.14";\[/code\]into this array:\[code\] $credit_packages = array( array( 'credit_amount'=> 300, 'price_per_credit'=>0.25), array( 'credit_amount'=> 1000, 'price_per_credit'=>0.24), array( 'credit_amount'=> 3000, 'price_per_credit'=>0.22), array( 'credit_amount'=> 4000, 'price_per_credit'=>0.20), array( 'credit_amount'=> 5000, 'price_per_credit'=>0.18), array( 'credit_amount'=> 6000, 'price_per_credit'=>0.16), array( 'credit_amount'=> 7000, 'price_per_credit'=>0.14) );\[/code\]how would you do it in a most efficient way?