Datepicker doesn't show weekdays in other languages and a Setter

[Megamisama]

In the original control pickdate.js you can change the weekdays of the month (S M T W T F S) by filling the Pickdate.DateOptions in weekdaysShort array with values like ['Dom', 'Lun', 'Mar', 'Mie', 'Jue', 'Vie', 'Sab'] but here only shows those values while mouse hovers over those.
http://amsul.ca/pickadate.js/date/#formats_prefill

The other problem I got is about how to set the control programmatically in a given value by me. In pickdate.js this can be archived by picker.set('select', Value). Shown in http://amsul.ca/pickadate.js/api/#item-objects but here I got no Idea.

[HeloiseH]

You can change the weekdays letter with this option :
weekdaysLetter: ['D', 'L', 'M', 'M', 'J', 'V', 'S'].

To set the value programmatically, I think you juste have to define an ngModel and set it in your component (with the correct format defined in formatSubmit option) :
[(ngModel)]="dateOfBirth" (in your html)
dateOfBirth = '2017-08-12'; (in your ts)