triggers problems whit function

I want to use a function in to a trigger

This is my

CREATE FUNCTION "subradio"(integer) RETURNS integer AS 'select cast(count (claveubica) as integer ) from asradios where ubicacion =0;' LANGUAGE 'sql';

And my ttrigger is

CREATE TRIGGER validaradios AFTER DELETE ON subestacion FOR EACH ROW EXECUTE PROCEDURE subradio(0);

But I got an error

ERROR: CreateTrigger: function subradio() does not exist

What can I do??

Ing. María Cristina Peña C.

Analista Programador

Sensa Control Digital S.A. de C.V.

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Col. Centro.
Torreón Coah.

Tel. Directo: (871) 747 01 04

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Correo Electrónico: mpena(at)sensacd(dot)com(dot)mx <mailto:rlopezr(at)sensacd(dot)com(dot)mx>