On Mon, 08 Sep 2014 14:58:14 -0400, mcp6453 wrote:

How do you match a paint color on drywall in a bedroom? Cut out of piece of the wall and take it to the paint store? Is
there such thing as a portable color analyzer?

There are portable analyzers out there. Ben Moore dealers used to sell
one. A bit spendy and not particularly accurate. As others have
advised, take a painted switch plate or cut a piece of the top drywall
surface in an inconspicuous spot. Go to a real paint store, not a big
box store. That being said, don't expect a perfect match that will
make an invisible touch up mid-wall. You'll get very close but that is
all. Plan to repaint the problem wall corner to corner.