Access a field by PHP

Hi all,

first of all, sorry for my poor english.
This is the problem:
I am not able to access a field in a form by PHP.
I call this event:
{fn:leggi_pensionato}
{view:pensionato_form}
{debug:}
The view content is: {view:pensionato_form_fields}
All the fields are correcty viewed but i am not able to test a field content by PHP.
I know i can not use the shortcode directly in a PHP action, and therefore i use this function: $this->data("field_name", "default value").
I attach the output of debug:
_________________________________________________________________
Array
(
[conn] => pensionati
[pensionato_id] => 1
[event] => edit_pensionato
[Itemid] => 324
[option] => com_chronoconnectivity6
[view] => connection
)

Array
(
[leggi_pensionato] => Array
(
[log] => Array
(
[0] => SELECT COUNT(`Pensionato`.`id`) AS `Pensionato.count` FROM `mytable_pensionati` AS `Pensionato` WHERE `Pensionato`.`id` = '1';
[1] => SELECT `Pensionato`.`id` AS `Pensionato.id`, `Pensionato`.`categoria` AS `Pensionato.categoria`, `Pensionato`.`name` AS `Pensionato.name`, `Pensionato`.`datanascita` AS `Pensionato.datanascita`, `Pensionato`.`username` AS `Pensionato.username`, `Pensionato`.`email` AS `Pensionato.email`, `Pensionato`.`datains` AS `Pensionato.datains`, `Pensionato`.`note` AS `Pensionato.note`, `Pensionato`.`matricola` AS `Pensionato.matricola`, `Pensionato`.`email2` AS `Pensionato.email2`, `Pensionato`.`iniziospettanza` AS `Pensionato.iniziospettanza`, `Pensionato`.`pensionato` AS `Pensionato.pensionato`, `Pensionato`.`dantecausa` AS `Pensionato.dantecausa`, `Pensionato`.`fisso` AS `Pensionato.fisso`, `Pensionato`.`mobile` AS `Pensionato.mobile`, `Pensionato`.`ufficio` AS `Pensionato.ufficio`, `Pensionato`.`indirizzo` AS `Pensionato.indirizzo`, `Pensionato`.`cap` AS `Pensionato.cap`, `Pensionato`.`citta` AS `Pensionato.citta`, `Pensionato`.`provincia` AS `Pensionato.provincia`, `Pensionato`.`stato` AS `Pensionato.stato`, `Pensionato`.`created` AS `Pensionato.created`, `Pensionato`.`created_by` AS `Pensionato.created_by`, `Pensionato`.`modified` AS `Pensionato.modified`, `Pensionato`.`modified_by` AS `Pensionato.modified_by` FROM `mytable_pensionati` AS `Pensionato` WHERE `Pensionato`.`id` = '1' LIMIT 30;
)

[var] => Array
(
[Pensionato] => Array
(
[id] => 1
[categoria] => Iscritto
[name] => Paolino Paperino
[datanascita] => 15/03/1954
[username] => paolino.paperino
[email] => alfa@gmail.com
[datains] => 07/10/2014
[note] =>
[matricola] => 00001234
[email2] =>
[iniziospettanza] => 01/01/2001
[pensionato] => diretto
[dantecausa] =>
[fisso] =>
[mobile] => 12345678
[ufficio] =>
[indirizzo] => Via Alfa Beta, 162
[cap] => 00136
[citta] => ROMA
[provincia] => RM
[stato] =>
[created] => 0000-00-00 00:00:00
[created_by] =>
[modified] => 2017-08-11 08:48:17
[modified_by] => Nome Cognome
)

)

)

)
____________________________________________________________________
I tried to access the "matricola" field by this code:
$this->data(["leggi_pensionato"]["Pensionato"]["matricola"],"00003145")
The funcion's result is "Array".
What is the correct "field_name" to pass the function and obtain "00001234"?

Best regards to all

Perfect!

Thank you very much.

Patrizio