PHP Converting Currency and Splitting Data (NOK and Bitcoin)

Question

I'm trying to write a basic PHP NOK to BTC / BTC to NOK conversion.

I'm not that great in math and It's confusing me on how to completely convert it.. & also I'm having trouble with splitting the links data (link below), to determine the currency.

(NOK = Norwegian Krone) (BTC = Bitcoin)

This is what I'm using to determine how much 1 BTC costs in NOK.

http://data.mtgox.com/api/1/BTCNOK/ticker_fast

So for example 1 BTC = 4478.17724 NOK (currently)

So I want to be able to enter something like

$nok = 100.00; // How much NOK I have / Trying to convert

$BTC = 4478.17724; //How much 1 BTC in NOK costs

This may sound stupid, but what math functions would I need to use to determine how much of 1 BTC I would get for how much $nok I have?

I would assume divide BTC by NOK , but I feel like that isn't correct.

Second, how would I extract the number "4478.17724" (for example) from ttp://data.mtgox.com/api/1/BTCNOK/ticker_fast

I know I can use str_split() or explode, but Is that the right approach? just assuming the placement of the number rather then searching an array for it.

Thanks again for all the help and replies.

Answer 1

The site is returning JSON so you would use something like http://nz1.php.net/json_decode to decode the JSON and access the data.

As your exchange rate is shown relative to BTC, to convert you would do the following.

$nok/$BTC i.e. you would divide your $nok amount by the exchange rate.

So in your example 100/4478.17724 = 0.0223305 BTC.