Those are going to be log2 copy number values for each gene, almost certainly after the data is segmented. If you want to roughly calculate the absolute copy number at that position, you can convert out of log2 and round to the nearest integer:
So for one of your values:
log2 cn: 0.4194
This is the ratio between tumor and normal (or between your cell line and a panel of "normal" cells)
To convert to absolute copy number, we do
(2^0.4194)*2 = 2.674742
The multiplication by two is because we assume a diploid genome in the normal.
Rounding, you'd probably say this gene was duplicated and there are three copies.
This is not the ideal way to calculate absolute copy number, but given the information you have, I think it'll be about as good as you can get.