[Arhowk]

Originally Posted by RufflesRidge

The sample on that page seems to be missing a line:

prefs = Preferences.getInstance();

You're right! Thats quite funny. Here's the actual code for reference

package org.usfirst.frc.team40.robot;

import edu.wpi.first.wpilibj.SampleRobot;
import edu.wpi.first.wpilibj.Preferences;

public class Robot extends SampleRobot{

    Preferences prefs;
    double armUpPosition;
    double armDownPosition;
    public void robotInit(){
        prefs = Preferences.getInstance();
        armUpPosition = prefs.getDouble("ArmUpPosition", 1.0);
        armDownPosition = prefs.getDouble("ArmDownPosition", 4.0);
    }
}

On a side note, to follow NetworkTable conventions the method name should be "getNumber" but that is trivial.