Modifying Names from (x,y] into x

Hi,

I have the following data that looks like this:

names(dat)

[1] "(-2329,-2319]"         "(-1399,-1389]"         "(-669.4,-659.4]"

How can I modify those names into just this?

[1] -2329   -1399 -669.4




- Gundala Viswanath
Jakarta - Indonesia