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<p class="MsoNormal"><span lang="EN-US">Hi everyone<o:p></o:p></span></p>
<p class="MsoNormal"><span lang="EN-US"><o:p> </o:p></span></p>
<p class="MsoNormal"><span lang="EN-US">I can’t find a way to tell if two linestrings “really” cross each other.<o:p></o:p></span></p>
<p class="MsoNormal"><span lang="EN-US"><o:p> </o:p></span></p>
<p class="MsoNormal"><span lang="EN-US">For instance if I have this linestring :<o:p></o:p></span></p>
<p class="MsoNormal"><span lang="EN-US">Line1 : LINESTRING(0 0, 1 1, 2 0)<o:p></o:p></span></p>
<p class="MsoNormal"><span lang="EN-US"><o:p> </o:p></span></p>
<p class="MsoNormal"><span lang="EN-US">How can I differentiate the relation of line 1 with one of the following :<o:p></o:p></span></p>
<p class="MsoNormal"><span lang="EN-US">Line2 : LINESTRING(0 2, 1 1, 2 2) -> no “real” cross, just a contact point<o:p></o:p></span></p>
<p class="MsoNormal"><span lang="EN-US">Line3 : LINESTRING(0 2, 1 1, 1 0) -> lines “really” cross each other<o:p></o:p></span></p>
<p class="MsoNormal"><span lang="EN-US"><o:p> </o:p></span></p>
<p class="MsoNormal"><span lang="EN-US">I can’t find a good combination of crosses, touches, etc… to differentiate these cases.<o:p></o:p></span></p>
<p class="MsoNormal"><span lang="EN-US"><o:p> </o:p></span></p>
<p class="MsoNormal"><span lang="EN-US">Thanks in advance<o:p></o:p></span></p>
<p class="MsoNormal"><span lang="EN-US">Jasmin<o:p></o:p></span></p>
<p class="MsoNormal"><span lang="EN-US"><o:p> </o:p></span></p>
<p class="MsoNormal"><span lang="EN-US"><o:p> </o:p></span></p>
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