[RESOLVED] preg_replace with array patterns

[Bushman]

Given an input string like "TACTTGATUATC", I need to replace all the T's with A's, the G's with C's, etc. I've been using

$inputpattern = array("/A/","/T/","/G/","/C/");
$outputpattern = array("U","A","C","G");
$output = preg_replace ($inputpattern,$outputpattern,$_POST["forminput"]);

but it does not work properly. When I had it print the result of

TACTTGAGTATC[CODE]
as input, it came out as
[CODE]AUGAAGUGAUAG

,and when I tried a different input,

TACGGGGGGATC

, it came out as

AUGGGGGGGUAG

So, for some wayward reason the preg_replace consistently fails to match that third array element of the input pattern ("/G/"). Am I doing something wrong and not noticing it?

[Weedpacket]

The replacements are carried out consecutively; all the As are changed to Us, then all the Ts are changed to As then all the Gs are changed to Cs and then all the Cs are changed to Gs - including those that were originally Gs already.

What you're wanting in this case is [man]strtr[/man].

[Bushman]

It works! Thank you so much!