... the match expression doesn't capture the tilde character (~).

In general, I'm having difficulty figuring out the OP too, but I think the tilde will be captured by the first  . (dot) in the  .\d+\.\d+ expression.

Update: Since my guess is that the  ~ (tilde) character seems always to be present in  .\d+\.\d+ (e.g., ~0.00) groups, my inclination would be to specify it explicitly in the match expression:  ~\d+\.\d+