func (r *RNG) Float64() (v float64) {
again:
	v = float64(r.Uint64()>>11) / (1 << 53)
	if v == 1 {
		goto again
	}
	return
}
// Float64 returns a float64 uniformly in [0, 1).
// Not safe for concurrent callers.
Float64 returns a float64 uniformly in [0, 1).
Not safe for concurrent callers.
// Float64 returns a float64 uniformly in [ 0 1 ) . // Not safe for concurrent callers .
func (r *RNG) Float64() (v float64) {
again:
	v = float64(r.Uint64()>>11) / (1 << 53)
	if v == 1 {
		goto again
	}
	return
}
func ( r * RNG ) Float64 ( ) ( v float64 ) { again : v = float64 ( r . Uint64 ( ) >> 11 ) / ( 1 << 53 ) if v == 1 { goto again } return }
Float64 returns a float64 uniformly in [0, 1).
Float64 returns a float64 uniformly in [ 0 1 ) .