How to extract and convert images/photos exif GPS metadata to decimal format with exiftool?

I use the great ExifTool by Phil Harvey to extract GPS metadata from images.
The default output for GPS coordinates is styled liked this:
GPS Latitude                    : 48 deg 50' 47.01" N
GPS Longitude                   : 8 deg 35' 21.83" E

I wanted the GPS data formatted in decimal number style.

How i fixed it:
Run the exiftool with the commandline parameters -n -c %.8f and you get

GPS Latitude                    : 48.8463925
GPS Longitude                   : 8.58939861111111

I found the right hints here:
http://u88.n24.queensu.ca/exiftool/forum/index.php/topic,6176.msg30496.html#msg30496

ExifTool download and forum can be found here:
http://www.sno.phy.queensu.ca/~phil/exiftool/