XF 1.5 Name of a day in a template

[Robert9]

I have to show a list like

Tuesday ...
Wedensday ...

I can pass the number of a day to the template. I could solve it by
xen:if lala ==1 phrase_monday
elseif lala =2 phrase tuesday.

But there is a better way, i hope?

How can say {xen:date "dayname of x"} ?
while x = {0|6}