\d+a Unicode decimal digit, repeated at least once
\s*a Unicode whitespace character, repeated any number of times
Non-Capturing Group(?:[,.]\d+)? ?repeats the group contents below at most once:
,the literal , (4410 / 548 / 2C16)
.the literal . (4610 / 568 / 2E16)
\d+a Unicode decimal digit, repeated at least once
%the literal % (3710 / 458 / 2516)