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I have a database of latitude, longitude and radius in the following form: 

48180759,11518950,19.0

Both latitude and longitude are expressed in degrees but then multiplied by 1e6 (or 1000000). Radius, on the other hand, are expressed in meters. What I am trying to do is convert lat/lon into meters so that I can use geometric functions more accurately, especially the one that looks for intersects (overlaps between points).

EDIT: Unfortunately, I wasn't able to find a complete answer. At least, not in this web site. I will use Python for this task. As for the precision, I would like to have as best as possible (a few centimeters deviation at most).

Any ideas?

Kadir Şahbaz
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user706838
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    This question is asked quite frequently. Could you search on "convert lat lon" and review the existing answers? If there aren't any matches, then you'll need to update this question with the GIS software or programming language you intend to use, with an indication of the kind of precision you'll need (to determine if a spherical or spheroidal solution is needed). – Vince Dec 11 '14 at 12:10
  • Unfortunately, I wasn't able to find a complete answer. At least, not in this web site. I will use python for this task. As for the precision, I would like to have as best as possible (a few centimeters deviation only). – user706838 Dec 11 '14 at 13:05
  • Please update the question, so that those who would answer don't need to mine the comments for critical information. – Vince Dec 11 '14 at 13:16
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    radius = 19 ? This is more likely the height above ellipsoid (or you are not on Earth). Note that for accurate projection you need to know the coordinate system that you are in (e.g. WGS 84) otherwise your efforts for precision will be vain. Could you please add more information about the context of your problem, otherwise there is no good answer. – radouxju Dec 11 '14 at 14:01
  • I am not familiar with GIS systems at all, however, I confirm that all data are based on the WGS 84 Ellipsoid coordinate system. A 19 meter radius here means that the actual point could be anywhere within a cycle with center (48.180759 lat, 11.518950 lon) (expressed in decimal degrees) and 19 radius (expressed in meters). – user706838 Dec 11 '14 at 14:29
  • So your coordinates are in Germany Leipziger Straße 42, 80992 München, Germany see http://stackoverflow.com/questions/6778288/lat-lon-to-utm-to-lat-lon-is-extremely-flawed-how-come for python – Mapperz Dec 11 '14 at 14:47
  • thanks @Mapperz but it's not clear how to use your hint :( can you please evolve? – user706838 Dec 11 '14 at 15:09
  • Ah, so you're doing a search within a circle. Then you should not necessarily project your data (unless it's to azimuthal equidistant centered at the point) but look at geodesic buffer solutions. Try this question. – mkennedy Dec 11 '14 at 17:50
  • @mkennedy Not sure if it's to azimuthal equidistant centered at the point. What I am really sure about though it is that it's based on the WGS 84 Ellipsoid coordinate system. My feeling is that the solution must be relative simple but I don't know how to do that. Could you please provide a hands-on solution? – user706838 Dec 11 '14 at 18:08

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A variety of methods are used in this link below, you can choose different methods according to your actual situation.

[https://stackoverflow.com/questions/639695/how-to-convert-latitude-or-longitude-to-meters?answertab=votes#tab-top][1]

sun
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