How do I convert from this weird Coordinate unit to LngLat for use in Google Maps?

I have a database full of rows if coordinate pairs like this:

ux: 6643641

uy: 264274

uz: NULL

I have been tasked to make all these coordin开发者_StackOverflow社区ates appear on google maps as points of interest, but nobody could tell me what the hell those coordinates were.

What I need for Google Maps is longitude and lengtitude coordinates. I know the one can be converted to the other, but nothing more.

I realize this might not be the correct place to ask about coordinate systems, but I honestly couldn't think of any other place to state the question.

Thanks for any help!

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That's my bad, I now see that there is more data for each row:

CoordSystemNumber: 23

CoordSystemName: EUREF89 UTM Sone 33

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I think that format is called UTM. You need to know the Zone and Hemisphere to complete the conversion. Is there other data associated with this?

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Tell me if this seems helpful :

x =   882880 meters
y = -4924482 meters
z =  3944130 meters

Geocentric latitude and longitude are not commonly used, but they are defined by
    latitude  = arctan( z / sqrt( x^2 + y^2 ) )
    longitude = arctan( y / x )

Taken from here : http://www.cv.nrao.edu/~rfisher/Ephemerides/earth_rot.html

see this too : http://en.wikipedia.org/wiki/Geographic_coordinate_system

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This wikipedia article might offer some help.

The coordinates are often chosen such that one of the numbers represent vertical position, and two or three of the numbers represent horizontal position. A common choice of coordinates is latitude, longitude and elevation.