Truncating alphabets and other characters from string

[watsmyname]

Hello,

 

Well i have var $string var, which might hold a string like this "$23.59 per pack", "$23.59/boxes","23.59 per vial" and so on and in any form. All i need to do is truncate all characters and leave only numeric value, i.e 23.59 only. All i could think is using array of those unwanted words and replace them with a blank space.

is there any way to do this task easily?

 

Thanks in advance

[inversesoft123]

$new_string = ereg_replace("[^.0-9]", "", $string);

[jl5501]

or

 

$new_string = preg_replace ('/[^\d\s.]/', '', $string);

[watsmyname]

Thanks a ton guys