function problem

[ABHANG RANE <arane@xxxxxxxxxxx>]

Hi,
I have written a function called similarity in postgresql which accepts 
real[] as argument. I then call it by saying

select * from similarity('{1.232,5.0000, 5.100, 10000}');

I get this error.

Could not choose a best candidate function. You may need to add 
explicit type casts.

Is it the way I call is wrong?

Thanks
Abhang