Hi Pradeep<br><br>I don't know what you exactly mean by midpoint of a MULTILINESTRING. If what you are looking for is the point on the multilinestring located half way on a imaginary linestring that have the total length of the MULTILINESTRING and is formed by sewing together
constituent linestrings I can write a function that do this. Must it fill the gaps between end point of first linestring and start point of second linestring (i.e. consider the space between consecutive linestrings as part of this imaginary linestring)? If you have any other detail about the function you want tell me.
<br><br>Rodrigo.<br><br><div><span class="gmail_quote">On 6/21/07, <b class="gmail_sendername">Pradeep B V</b> <<a href="mailto:pradeepbv@gmail.com">pradeepbv@gmail.com</a>> wrote:</span><blockquote class="gmail_quote" style="border-left: 1px solid rgb(204, 204, 204); margin: 0pt 0pt 0pt 0.8ex; padding-left: 1ex;">
Is there any other function equivalent to the <span>line_interpolate_point(the_geom, 0.5) to find the midpoint of a MULTILINESTRING?<br><br>the </span><span>line_interpolate_point works only with LINESTRINGS.<br><span class="sg">
<br>- Pradeep B V
<br><a href="http://www.btis.in" target="_blank" onclick="return top.js.OpenExtLink(window,event,this)">www.btis.in</a><br></span></span><div><span class="e" id="q_1134e464d0b39005_3"><span><br></span><br><div><span class="gmail_quote">
On 6/21/07, <b class="gmail_sendername">Rodrigo Martín LÓPEZ GREGORIO</b> <<a href="mailto:rodrigomartin@lopezgregorio.com.ar" target="_blank" onclick="return top.js.OpenExtLink(window,event,this)">
rodrigomartin@lopezgregorio.com.ar</a>> wrote:</span><blockquote class="gmail_quote" style="border-left: 1px solid rgb(204, 204, 204); margin: 0pt 0pt 0pt 0.8ex; padding-left: 1ex;">Hi Matt.<br><br>I think what you want may be:
<br><br><span>line_interpolate_point(the_geom,0.5)<br><br>(or ST_</span><span>line_interpolate_point(the_geom,0.5) depending on your Postgis version)</span>
<br><span><br>where the_geom is a linestring and 0.5 means half of the total 2d length of the linestring.<br><br>You can reed more details in the documentation:<br><br><a href="http://postgis.refractions.net/docs/ch06.html#line_interpolate_point" target="_blank" onclick="return top.js.OpenExtLink(window,event,this)">
http://postgis.refractions.net/docs/ch06.html#line_interpolate_point</a><br><br>Rodrigo<br></span><br><div><span class="gmail_quote">On 6/21/07, <b class="gmail_sendername">Matt Doughty</b> <<a href="mailto:matt.doughty@geograma.com" target="_blank" onclick="return top.js.OpenExtLink(window,event,this)">
matt.doughty@geograma.com</a>> wrote:</span><blockquote class="gmail_quote" style="border-left: 1px solid rgb(204, 204, 204); margin: 0pt 0pt 0pt 0.8ex; padding-left: 1ex;">
<div link="blue" vlink="purple" lang="ES">
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<p><font face="Arial" size="2"><span style="font-size: 10pt; font-family: Arial;" lang="EN-GB">Hi List,</span></font></p>
<p><font face="Arial" size="2"><span style="font-size: 10pt; font-family: Arial;" lang="EN-GB"> </span></font></p>
<p><font face="Arial" size="2"><span style="font-size: 10pt; font-family: Arial;" lang="EN-GB">Is there a function in PostGIS that finds the
midpoint of a line?</span></font></p>
<p><font face="Arial" size="2"><span style="font-size: 10pt; font-family: Arial;" lang="EN-GB"> </span></font></p>
<p><font face="Arial" size="2"><span style="font-size: 10pt; font-family: Arial;" lang="EN-GB">Matt</span></font></p>
<p><font face="Arial" size="2"><span style="font-size: 10pt; font-family: Arial;" lang="EN-GB"> </span></font></p>
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<p><font color="#2e3a75" face="Arial" size="3"><span style="font-size: 12pt; font-family: Arial; color: rgb(46, 58, 117);" lang="EN-GB">Matt Doughty</span></font><span lang="EN-GB"></span></p>
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A S.L.</span></font><font face="Arial"><span style="font-family: Arial;"></span></font></p>
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<p><font color="#2e3a75" face="Arial" size="3"><span style="font-size: 12pt; font-family: Arial; color: rgb(46, 58, 117);">Tel.:
+34 945 13 13 72 652 77 14 15</span></font><font face="Arial"><span style="font-family: Arial;"></span></font></p>
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