Extract Initials

Hello everyone, 

I have this formula (Rich Text field )

var text FirstName = If([PreferredFirstName]="", [FirstName], [PreferredFirstName]);
var text MiddleName = If([PreferredMiddleName]="", [MiddleName], [PreferredMiddleName]);
var text LastName = If([PreferredLastName]="", [LastName],[PreferredLastName]);

$LastName&", "&$FirstName&" "&$MiddleName

OUTPUT: "Ponce Edson I"

HOWEVER, I AM LOOKING TO USED THE SAME FORMULA IF IS POSSIBLE THAT THE OUTPUT WILL BE ONLY INITIAL 

OUTPUT WILL BE:   "PEI"




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Edson
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