You should first look carefully at you data. In your first e-mail you said one of the points was:<br><br>"X = 1550428 Y = 2447336 and should be a point closer to lat = 41,8905198 lng = 12,4942486"<br><br>The geographic coordinates correspond in fact to a point in Rome. But now you give X,Y coordinates like <br>
<br>2447857 1069853<br><br>If coordinates are meters, this point is very far from Rome, even if you change the order in one of the points!...<br><br>Regards<br><br>José<br><br><br><br><div class="gmail_quote">2011/11/11 Vincenzo Ampolo <span dir="ltr"><<a href="mailto:vincenzo.ampolo@gmail.com">vincenzo.ampolo@gmail.com</a>></span><br>
<blockquote class="gmail_quote" style="margin:0 0 0 .8ex;border-left:1px #ccc solid;padding-left:1ex;">
<div bgcolor="#FFFFFF" text="#000000"><div class="im">
On 11/11/2011 11:28 AM, JAG wrote:
<blockquote type="cite">
<pre>Looking only to the geographic coordinates, the differences are 3.6 deg in latitude and 3.3 deg in longitude. That is approximately 400 km in latitude and 270 km in longitude, which does not agree with the area you refer.
Regards
José</pre>
</blockquote></div>
Sorry, i didn't mean that the two points are close together. They
are from different datasets.<br>
<br>
I've 40.000 points which are all close to <br><div class="im">
<pre>lat = 41,8905198
lng = 12,4942486</pre></div>
Which is Rome (italy)<br>
<br>
And other 40.000 points which are all close to<div class="im"><br>
<pre>lat = 45,463681
lng = 9,1881714</pre></div>
which is Milan (Italy)<br>
<br>
This is some data i've for the first set of points (around Rome)<br>
<br>
<table frame="VOID" rules="NONE" border="0" cellspacing="0" cols="4">
<colgroup><col width="84"><col width="84"><col width="84"><col width="317"></colgroup> <tbody>
<tr>
<td style="border-top:1px solid #000000;border-left:1px solid #000000;border-right:1px solid #000000" align="LEFT" bgcolor="#CCFFCC" height="61" width="84"><i><font color="#000000" face="Calibri" size="3">GeoX
(M)</font></i></td>
<td style="border-top:1px solid #000000;border-left:1px solid #000000;border-right:1px solid #000000" align="LEFT" bgcolor="#CCFFCC" width="84"><i><font color="#000000" face="Calibri" size="3">GeoY (N)</font></i></td>
<td style="border-top:1px solid #000000;border-left:1px solid #000000;border-right:1px solid #000000" align="LEFT" bgcolor="#CCFFCC" width="84"><i><font color="#000000" face="Calibri" size="3">Colonna comune
(B)</font></i></td>
<td style="border-top:1px solid #000000;border-left:1px solid #000000;border-right:1px solid #000000" align="LEFT" bgcolor="#CCFFCC" width="317"><i><font color="#000000" face="Calibri" size="3">Colonna
indirizzo (D)</font></i></td>
</tr>
<tr>
<td align="RIGHT" height="19">2447857</td>
<td align="RIGHT">1069853</td>
<td align="LEFT"><font face="MS Sans Serif">ROMA</font></td>
<td align="LEFT">CIRCONVALLAZIONE GIANICOLENSE</td>
</tr>
<tr>
<td align="RIGHT" height="22"><font color="#000000" face="Calibri" size="3">2447336</font></td>
<td align="RIGHT"><font color="#000000" face="Calibri" size="3">1075588</font></td>
<td align="LEFT"><font face="MS Sans Serif">ROMA</font></td>
<td align="LEFT"><font color="#000000" face="Calibri" size="3">CIRCONVALLAZIONE
CLODIA</font></td>
</tr>
<tr>
<td align="RIGHT" height="22"><font color="#000000" face="Calibri" size="3">2447336</font></td>
<td align="RIGHT"><font color="#000000" face="Calibri" size="3">1075588</font></td>
<td align="LEFT"><font face="MS Sans Serif">ROMA</font></td>
<td align="LEFT"><font color="#000000" face="Calibri" size="3">CIRCONVALLAZIONE
CLODIA</font></td>
</tr>
<tr>
<td align="RIGHT" height="22"><font color="#000000" face="Calibri" size="3">2451643</font></td>
<td align="RIGHT"><font color="#000000" face="Calibri" size="3">1077238</font></td>
<td align="LEFT"><font face="MS Sans Serif">ROMA</font></td>
<td align="LEFT"><font color="#000000" face="Calibri" size="3">VIALE
SOMALIA</font></td>
</tr>
<tr>
<td align="RIGHT" height="22"><font color="#000000" face="Calibri" size="3">2447857</font></td>
<td align="RIGHT"><font color="#000000" face="Calibri" size="3">1069853</font></td>
<td align="LEFT"><font face="MS Sans Serif">ROMA</font></td>
<td align="LEFT"><font color="#000000" face="Calibri" size="3">CIRCONVALLAZIONE
GIANICOLENSE</font></td>
</tr>
<tr>
<td align="RIGHT" height="22"><font color="#000000" face="Calibri" size="3">2457129</font></td>
<td align="RIGHT"><font color="#000000" face="Calibri" size="3">1068315</font></td>
<td align="LEFT"><font face="MS Sans Serif">ROMA</font></td>
<td align="LEFT"><font color="#000000" face="Calibri" size="3">CIRCONVALLAZIONE
TUSCOLANA</font></td>
</tr>
<tr>
<td align="RIGHT" height="22"><font color="#000000" face="Calibri" size="3">2457129</font></td>
<td align="RIGHT"><font color="#000000" face="Calibri" size="3">1068315</font></td>
<td align="LEFT"><font face="MS Sans Serif">ROMA</font></td>
<td align="LEFT"><font color="#000000" face="Calibri" size="3">CIRCONVALLAZIONE
TUSCOLANA</font></td>
</tr>
<tr>
<td align="RIGHT" height="22"><font color="#000000" face="Calibri" size="3">2448230</font></td>
<td align="RIGHT"><font color="#000000" face="Calibri" size="3">1077592</font></td>
<td align="LEFT"><font face="MS Sans Serif">ROMA</font></td>
<td align="LEFT"><font color="#000000" face="Calibri" size="3">CORSO
DI FRANCIA</font></td>
</tr>
<tr>
<td align="RIGHT" height="22"><font color="#000000" face="Calibri" size="3">2448560</font></td>
<td align="RIGHT"><font color="#000000" face="Calibri" size="3">1069650</font></td>
<td align="LEFT"><font face="MS Sans Serif">ROMA</font></td>
<td align="LEFT"><font color="#000000" face="Calibri" size="3">PIAZZA
DELLA RADIO</font></td>
</tr>
<tr>
<td align="RIGHT" height="22"><font color="#000000" face="Calibri" size="3">2456036</font></td>
<td align="RIGHT"><font color="#000000" face="Calibri" size="3">1078472</font></td>
<td align="LEFT"><font face="MS Sans Serif">ROMA</font></td>
<td align="LEFT"><font color="#000000" face="Calibri" size="3">VIA
DIEGO FABBRI</font></td>
</tr>
<tr>
<td align="RIGHT" height="22"><font color="#000000" face="Calibri" size="3">2446575</font></td>
<td align="RIGHT"><font color="#000000" face="Calibri" size="3">1067372</font></td>
<td align="LEFT"><font face="MS Sans Serif">ROMA</font></td>
<td align="LEFT"><font color="#000000" face="Calibri" size="3">VIALE
ISACCO NEWTON</font></td>
</tr>
<tr>
<td align="RIGHT" height="22"><font color="#000000" face="Calibri" size="3">2448230</font></td>
<td align="RIGHT"><font color="#000000" face="Calibri" size="3">1077592</font></td>
<td align="LEFT"><font face="MS Sans Serif">ROMA</font></td>
<td align="LEFT"><font color="#000000" face="Calibri" size="3">CORSO
DI FRANCIA</font></td>
</tr>
<tr>
<td align="RIGHT" height="22"><font color="#000000" face="Calibri" size="3">2448230</font></td>
<td align="RIGHT"><font color="#000000" face="Calibri" size="3">1077592</font></td>
<td align="LEFT"><font face="MS Sans Serif">ROMA</font></td>
<td align="LEFT"><font color="#000000" face="Calibri" size="3">CORSO
DI FRANCIA</font></td>
</tr>
<tr>
<td align="RIGHT" height="22"><font color="#000000" face="Calibri" size="3">2448850</font></td>
<td align="RIGHT"><font color="#000000" face="Calibri" size="3">1072702</font></td>
<td align="LEFT"><font face="MS Sans Serif">ROMA</font></td>
<td align="LEFT"><font color="#000000" face="Calibri" size="3">CORSO
VITTORIO EMANUELE II</font></td>
</tr>
<tr>
<td align="RIGHT" height="22"><font color="#000000" face="Calibri" size="3">2451492</font></td>
<td align="RIGHT"><font color="#000000" face="Calibri" size="3">1068723</font></td>
<td align="LEFT"><font face="MS Sans Serif">ROMA</font></td>
<td align="LEFT"><font color="#000000" face="Calibri" size="3">LARGO
BENEDETTO BOMPIANI</font></td>
</tr>
<tr>
<td align="RIGHT" height="22"><font color="#000000" face="Calibri" size="3">2454671</font></td>
<td align="RIGHT"><font color="#000000" face="Calibri" size="3">1080064</font></td>
<td align="LEFT"><font face="MS Sans Serif">ROMA</font></td>
<td align="LEFT"><font color="#000000" face="Calibri" size="3">VIA
FRANCO SIMONGINI</font></td>
</tr>
<tr>
<td align="RIGHT" height="22"><font color="#000000" face="Calibri" size="3">2447642</font></td>
<td align="RIGHT"><font color="#000000" face="Calibri" size="3">1078350</font></td>
<td align="LEFT"><font face="MS Sans Serif">ROMA</font></td>
<td align="LEFT"><font color="#000000" face="Calibri" size="3">VIA
DI VIGNA STELLUTI</font></td>
</tr>
<tr>
<td align="RIGHT" height="22"><font color="#000000" face="Calibri" size="3">2447642</font></td>
<td align="RIGHT"><font color="#000000" face="Calibri" size="3">1078350</font></td>
<td align="LEFT"><font face="MS Sans Serif">ROMA</font></td>
<td align="LEFT"><font color="#000000" face="Calibri" size="3">VIA
DI VIGNA STELLUTI</font></td>
</tr>
<tr>
<td align="RIGHT" height="22"><font color="#000000" face="Calibri" size="3">2447642</font></td>
<td align="RIGHT"><font color="#000000" face="Calibri" size="3">1078350</font></td>
<td align="LEFT"><font face="MS Sans Serif">ROMA</font></td>
<td align="LEFT"><font color="#000000" face="Calibri" size="3">VIA
DI VIGNA STELLUTI</font></td>
</tr>
<tr>
<td align="RIGHT" height="22"><font color="#000000" face="Calibri" size="3">2447642</font></td>
<td align="RIGHT"><font color="#000000" face="Calibri" size="3">1078350</font></td>
<td align="LEFT"><font face="MS Sans Serif">ROMA</font></td>
<td align="LEFT"><font color="#000000" face="Calibri" size="3">VIA
DI VIGNA STELLUTI</font></td>
</tr>
<tr>
<td align="RIGHT" height="22"><font color="#000000" face="Calibri" size="3">2447642</font></td>
<td align="RIGHT"><font color="#000000" face="Calibri" size="3">1078350</font></td>
<td align="LEFT"><font face="MS Sans Serif">ROMA</font></td>
<td align="LEFT"><font color="#000000" face="Calibri" size="3">VIA
DI VIGNA STELLUTI</font></td>
</tr>
<tr>
<td align="RIGHT" height="22"><font color="#000000" face="Calibri" size="3">2450834</font></td>
<td align="RIGHT"><font color="#000000" face="Calibri" size="3">1067730</font></td>
<td align="LEFT"><font face="MS Sans Serif">ROMA</font></td>
<td align="LEFT"><font color="#000000" face="Calibri" size="3">PIAZZALE
DEL CARAVAGGIO</font></td>
</tr>
<tr>
<td align="RIGHT" height="22"><font color="#000000" face="Calibri" size="3">2447187</font></td>
<td align="RIGHT"><font color="#000000" face="Calibri" size="3">1074983</font></td>
<td align="LEFT"><font face="MS Sans Serif">ROMA</font></td>
<td align="LEFT"><font color="#000000" face="Calibri" size="3">PIAZZALE
CLODIO</font></td>
</tr>
<tr>
<td align="RIGHT" height="22"><font color="#000000" face="Calibri" size="3">2447187</font></td>
<td align="RIGHT"><font color="#000000" face="Calibri" size="3">1074983</font></td>
<td align="LEFT"><font face="MS Sans Serif">ROMA</font></td>
<td align="LEFT"><font color="#000000" face="Calibri" size="3">PIAZZALE
CLODIO</font></td>
</tr>
<tr>
<td align="RIGHT" height="22"><font color="#000000" face="Calibri" size="3">2446665</font></td>
<td align="RIGHT"><font color="#000000" face="Calibri" size="3">1073922</font></td>
<td align="LEFT"><font face="MS Sans Serif">ROMA</font></td>
<td align="LEFT"><font color="#000000" face="Calibri" size="3">PIAZZALE
DEGLI EROI</font></td>
</tr>
<tr>
<td align="RIGHT" height="22"><font color="#000000" face="Calibri" size="3">2448836</font></td>
<td align="RIGHT"><font color="#000000" face="Calibri" size="3">1074408</font></td>
<td align="LEFT"><font face="MS Sans Serif">ROMA</font></td>
<td align="LEFT"><font color="#000000" face="Calibri" size="3">PIAZZALE
FLAMINIO</font></td>
</tr>
<tr>
<td align="RIGHT" height="22"><font color="#000000" face="Calibri" size="3">2447369</font></td>
<td align="RIGHT"><font color="#000000" face="Calibri" size="3">1075612</font></td>
<td align="LEFT"><font face="MS Sans Serif">ROMA</font></td>
<td align="LEFT"><font color="#000000" face="Calibri" size="3">PIAZZALE
MARESCIALLO GIARDINO</font></td>
</tr>
<tr>
<td align="RIGHT" height="22"><font color="#000000" face="Calibri" size="3">2447369</font></td>
<td align="RIGHT"><font color="#000000" face="Calibri" size="3">1075612</font></td>
<td align="LEFT"><font face="MS Sans Serif">ROMA</font></td>
<td align="LEFT"><font color="#000000" face="Calibri" size="3">PIAZZALE
MARESCIALLO GIARDINO</font></td>
</tr>
<tr>
<td align="RIGHT" height="22"><font color="#000000" face="Calibri" size="3">2448234</font></td>
<td align="RIGHT"><font color="#000000" face="Calibri" size="3">1076254</font></td>
<td align="LEFT"><font face="MS Sans Serif">ROMA</font></td>
<td align="LEFT"><font color="#000000" face="Calibri" size="3">PIAZZA
APOLLODORO</font></td>
</tr>
<tr>
<td align="RIGHT" height="22"><font color="#000000" face="Calibri" size="3">2452382</font></td>
<td align="RIGHT"><font color="#000000" face="Calibri" size="3">1080020</font></td>
<td align="LEFT"><font face="MS Sans Serif">ROMA</font></td>
<td align="LEFT"><font color="#000000" face="Calibri" size="3">PIAZZA
DELL'ATENEO SALESIANO</font></td>
</tr>
<tr>
<td align="RIGHT" height="22"><font color="#000000" face="Calibri" size="3">2448494</font></td>
<td align="RIGHT"><font color="#000000" face="Calibri" size="3">1073731</font></td>
<td align="LEFT"><font face="MS Sans Serif">ROMA</font></td>
<td align="LEFT"><font color="#000000" face="Calibri" size="3">PIAZZA
CAVOUR</font></td>
</tr>
<tr>
<td align="RIGHT" height="22"><font color="#000000" face="Calibri" size="3">2456566</font></td>
<td align="RIGHT"><font color="#000000" face="Calibri" size="3">1070962</font></td>
<td align="LEFT"><font face="MS Sans Serif">ROMA</font></td>
<td align="LEFT"><font color="#000000" face="Calibri" size="3">PIAZZA
DELLE CAMELIE</font></td>
</tr>
<tr>
<td align="RIGHT" height="22"><font color="#000000" face="Calibri" size="3">2451500</font></td>
<td align="RIGHT"><font color="#000000" face="Calibri" size="3">1076660</font></td>
<td align="LEFT"><font face="MS Sans Serif">ROMA</font></td>
<td align="LEFT"><font color="#000000" face="Calibri" size="3">PIAZZA
DI PRISCILLA</font></td>
</tr>
<tr>
<td align="RIGHT" height="22"><font color="#000000" face="Calibri" size="3">2447346</font></td>
<td align="RIGHT"><font color="#000000" face="Calibri" size="3">1076534</font></td>
<td align="LEFT"><font face="MS Sans Serif">ROMA</font></td>
<td align="LEFT"><font color="#000000" face="Calibri" size="3">PIAZZA
LAURO DE BOSIS</font></td>
</tr>
<tr>
<td align="RIGHT" height="22"><font color="#000000" face="Calibri" size="3">2447584</font></td>
<td align="RIGHT"><font color="#000000" face="Calibri" size="3">1076916</font></td>
<td align="LEFT"><font face="MS Sans Serif">ROMA</font></td>
<td align="LEFT"><font color="#000000" face="Calibri" size="3">PIAZZALE
MARESCIALLO DIAZ</font></td>
</tr>
<tr>
<td align="RIGHT" height="22"><font color="#000000" face="Calibri" size="3">2447584</font></td>
<td align="RIGHT"><font color="#000000" face="Calibri" size="3">1076916</font></td>
<td align="LEFT"><font face="MS Sans Serif">ROMA</font></td>
<td align="LEFT"><font color="#000000" face="Calibri" size="3">PIAZZALE
MARESCIALLO DIAZ</font></td>
</tr>
<tr>
<td align="RIGHT" height="22"><font color="#000000" face="Calibri" size="3">2448307</font></td>
<td align="RIGHT"><font color="#000000" face="Calibri" size="3">1075184</font></td>
<td align="LEFT"><font face="MS Sans Serif">ROMA</font></td>
<td align="LEFT"><font color="#000000" face="Calibri" size="3">PIAZZA
MONTE GRAPPA</font></td>
</tr>
<tr>
<td align="RIGHT" height="22"><font color="#000000" face="Calibri" size="3">2445891</font></td>
<td align="RIGHT"><font color="#000000" face="Calibri" size="3">1072333</font></td>
<td align="LEFT"><font face="MS Sans Serif">ROMA</font></td>
<td align="LEFT"><font color="#000000" face="Calibri" size="3">PIAZZA
PIO XI</font></td>
</tr>
<tr>
<td align="RIGHT" height="22"><font color="#000000" face="Calibri" size="3">2447714</font></td>
<td align="RIGHT"><font color="#000000" face="Calibri" size="3">1078540</font></td>
<td align="LEFT"><font face="MS Sans Serif">ROMA</font></td>
<td align="LEFT"><font color="#000000" face="Calibri" size="3">PIAZZA
STEFANO JACINI</font></td>
</tr>
</tbody>
</table>
<br>
Thanks for all.<div class="im"><br>
<pre cols="72">--
Vincenzo Ampolo
<a href="http://vincenzo-ampolo.net" target="_blank">http://vincenzo-ampolo.net</a>
<a href="http://goshawknest.wordpress.com" target="_blank">http://goshawknest.wordpress.com</a></pre>
</div></div>
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