World Magnetic Model Android

Question

I'm attempting to include the World Magnetic Model in my app to determine magnetic declination through time. I see from the android developer page

http://developer.android.com/reference/android/hardware/GeomagneticField.html

that the current classes built into Android will only go back 1970.

Anyone know where to access the correction coefficients for prior to 1970 and also where do I find the actual Android GeomagneticField class so that I can alter it?

Answer 1

The class is in the AOSP at /android/hardware/GeomagneticField.java although to alter it you'd need to make a custom ROM. Its actually already build on WMM data. As for finding the coefficiencts, that's off topic for this forum. If I knew I'd just tell you, but I have no idea where to get them.