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    <p>Your post shows that 111.422006 becomes to 111.422004999999, this is a difference of 0.00001 which cannot happen due double to Double casting.</p> <p>This clearly shows that the reduction in precision is somewhere from emulator input and or internal GPS processing most probably for emulation purpose ( the emulator could interpolate when needed)</p> <p>For sure it is not caused by type double.</p> <p>For real GPS, even when android would cut off or round at the 6 digit after decimal points, this does not affect the positional accuarcy. gsp positions have an physical limit of 3m. when android would cut of that digit, the position can change by some centimeter. but that can safely be ignored, it is the position that the device tells, and that is the best known truth. you cannot improve. raising the number of digits does not improve GPS acuracy, you would need to have a better GpS antenna to improve acuracy.</p> <p><strong>Update:</strong><br> Here the granularity of coordinates in meters related to used number of latitude / longitude digits:</p> <p>This case is the worst case: the distance on equator from (0.0,0.0) to (0.0, lon2)</p> <pre><code>lon2= 0.1, meters = 11131.94558870502 lon2= 0.01, meters = 1113.194558870502 lon2= 0.0010, meters = 111.3194558870502 lon2= 1.0E-4, meters = 11.131945588705022 lon2= 1.0E-5, meters = 1.1131945588705023 lon2= 1.0E-6, meters = 0.11131945588705022 </code></pre> <p>So 0.000001 is 11cm</p> <p>You can calculate that by yourself, too:<br> Earth circumfence (approx) = 40.000 km<br> Divided by 360 degrees = 111.111 km = 111111 meters per degree (exactly it is 111319m) </p> <pre><code>1 digit after comma: 0.1: divide by 10= 11131.9 m 2 digits after comma: 0.01: divide by 100= 1113.19m </code></pre> <p>and so on, look at the table above. </p> <p>If you want the result more official: look at the link which asciimo has posted:<br></p> <p><a href="http://en.wikipedia.org/wiki/Decimal_degrees" rel="nofollow">Coordinates in Decimal degrees</a></p>
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    1. POLocation.getLatitude method returns non-precisioned double which is bad for GPS cordinates
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    1. POLocation.getLatitude method returns non-precisioned double which is bad for GPS cordinates
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    1. COI agree to most extend with you. Can you give citation that how much accuracy depends (in meters) on the last decimal (in 6 decimals). E.g if its 111.123459 . if 9 some how converts to 1. how much distance would it had been misrepresented?
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      1. USMasood Ahmad
    2. COYes i can, one moment please
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    3. CO@MasoodAhmad 9 to 1 is 8 * 11cm = 88cm on equator. (On all other places the error can be smaller) You can write a simple program and use the distance function: The Location class has a method distance(), just pass in the two coordinates to test and measure the distance: (111.123459, 0) and (111.123451, 0) which gives 89cm at my programm, which is the expected result.
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