fix bug in example. need to convert Value to float in Abs example
fix bug in example. need to convert Value to float in Abs example

R=adg
CC=golang-dev
http://codereview.appspot.com/2486043

ssrl/go,dsriram/golang,apparentlymart/golang,apparentlymart/golang,tv42/old-go,pombredanne/go-deleteme,h8liu/golang,gnanderson/go,dsriram/golang,gnanderson/go,gnanderson/go,dsriram/golang,dsriram/golang,ssrl/go,tv42/old-go,h8liu/golang,h8liu/golang,dsriram/golang,ssrl/go,pombredanne/go-deleteme,tv42/old-go,tv42/old-go,dsriram/golang,pombredanne/go-deleteme,apparentlymart/golang,h8liu/golang,ssrl/go,pombredanne/go-deleteme,pombredanne/go-deleteme,h8liu/golang,gnanderson/go,ssrl/go,pombredanne/go-deleteme,h8liu/golang,tv42/old-go,dsriram/golang,gnanderson/go,apparentlymart/golang,gnanderson/go,tv42/old-go,apparentlymart/golang,pombredanne/go-deleteme,apparentlymart/golang,tv42/old-go,apparentlymart/golang,h8liu/golang,ssrl/go,gnanderson/go,ssrl/go