<div dir="ltr"><div class="gmail_default" style="font-size:small">Thank you for your explanation, Tom.</div><div class="gmail_default" style="font-size:small"><br></div><div class="gmail_default" style="font-size:small">Let me explain the case clearly. </div><div class="gmail_default" style="font-size:small">The point layer is a very dense grid field collection across Great Britain. I wanted to do spatial cross-validation by specifying each point in one of the polygons (and assign a group of the polygons to a fold). Since the points have been sampled on a regular grid they sometimes fall exactly on the border of the polygons. If I use any sort of intersection or spatial join, the points on the borders cause a problem. </div><div class="gmail_default" style="font-size:small"><br></div><div class="gmail_default" style="font-size:small">Currently, I use st_jitter() in sf package give a bit of randomness to the points. I wanted to see if there is another systematic way to avoid this.</div><div class="gmail_default" style="font-size:small"><br></div><div class="gmail_default" style="font-size:small">Thanks,</div><div class="gmail_default" style="font-size:small">Roozbeh</div><div><div dir="ltr" class="gmail_signature" data-smartmail="gmail_signature"><div dir="ltr"><div dir="ltr"><div dir="ltr"><div dir="ltr"><div dir="ltr"><div dir="ltr"><div style="font-size:small"><div dir="ltr"><div dir="ltr"><div dir="ltr"><div dir="ltr"><div dir="ltr"><div dir="ltr"><div dir="ltr"><div dir="ltr"><div style="color:rgb(0,0,0);font-family:"times new roman","new york",times,serif"><font face="times new roman, new york, times, serif"><br></font></div><div style="color:rgb(0,0,0);font-family:"times new roman","new york",times,serif">PhD Candidate<br></div><div style="color:rgb(0,0,0);font-family:"times new roman","new york",times,serif"><font face="times new roman, new york, times, serif" size="2"><a href="http://qaeco.com/" rel="nofollow" style="color:rgb(25,106,212)" target="_blank">The Quantitative & Applied Ecology Group</a><br></font></div><div style="color:rgb(0,0,0);font-family:"times new roman","new york",times,serif"><font face="times new roman, new york, times, serif" size="2">School of BioSciences | Faculty of Science</font></div><div style="color:rgb(0,0,0);font-family:"times new roman","new york",times,serif"><font face="times new roman, new york, times, serif" size="2">The University of Melbourne,</font> VIC 3010, Australia</div><div style="color:rgb(0,0,0);font-family:"times new roman","new york",times,serif">M: +61 423 283 238 E: <a href="mailto:rvalavi@student.unimelb.edu.au" target="_blank">rvalavi@student.unimelb.edu.au</a><br></div></div></div></div></div></div></div></div></div></div></div></div></div></div></div></div></div></div><br></div><br><div class="gmail_quote"><div dir="ltr" class="gmail_attr">On Wed, May 1, 2019 at 3:16 PM Tom Philippi <<a href="mailto:tephilippi@gmail.com">tephilippi@gmail.com</a>> wrote:<br></div><blockquote class="gmail_quote" style="margin:0px 0px 0px 0.8ex;border-left:1px solid rgb(204,204,204);padding-left:1ex"><div dir="ltr"><div dir="ltr">Roozbeh--<div><br><div>What do you want to have happen with those points? Given the units in your figure, you could unambiguously assign them to the upper-right by adding a small value (0.000001) to both the X and Y coordinates of your points. Whether that is a sensible thing to do depends on what your data are.</div><div><br></div><div>How or why do the points fall exactly on your polygon boundaries? What process puts them exactly on the polygon (grid cell) boundaries? It appears your polygon boundaries are a grid at multiples of 0.05, although not all potential cells in a rectangle are shown. Are there many other points not on polygon boundaries not shown in your figure, or are points only along grid lines? If the latter, does it make sense to assign them to _polygons_ rather than line segments?</div><div><br></div><div>If you're doing a sample draw or measuring locations with only a few decimal points of accuracy, and generating your polygon boundaries at exact multiples of 0.05, then it might make sense to shift all of your points + 1/10th of your point location resolution so that their coordinates never fall on polygon boundaries. There _might_ be situations where instead of always adding (shifting up and right), you should randomly add or subtract in each direction for each point, but I'm stuck viewing this as points in sTomample units so I can't think of such a case.</div><div><br></div><div>Tom</div><div>. </div></div></div><br><div class="gmail_quote"><div dir="ltr" class="gmail_attr">On Tue, Apr 30, 2019 at 7:18 PM Roozbeh Valavi <<a href="mailto:rvalavi@student.unimelb.edu.au" target="_blank">rvalavi@student.unimelb.edu.au</a>> wrote:<br></div><blockquote class="gmail_quote" style="margin:0px 0px 0px 0.8ex;border-left:1px solid rgb(204,204,204);padding-left:1ex"><div dir="ltr"><div style="font-size:small">Dear members,<br></div><div style="font-size:small"><br></div><div style="font-size:small">I want to do a spatial join/intersection in R. The problem is that some of my points are lying exactly at the border of the adjacent polygons (see the figure attached). So these points are either falling in both or none of the polygons! Is there any way to avoid this?</div><div style="font-size:small"><br></div><div style="font-size:small">Thanks in advance.</div><div style="font-size:small">Roozbeh</div><div style="font-size:small"><br></div><div style="font-size:small"><br></div><div style="font-size:small"><div><img src="cid:ii_jv4l5cl61" alt="image.png" width="542" height="434"><br></div></div><div><br></div><div><br></div><div><br></div>-- <br><div dir="ltr" class="gmail-m_-5337304412789472482gmail-m_5080108255053228489gmail-m_-1351274462198299646gmail_signature"><div dir="ltr"><div><div dir="ltr"><div dir="ltr"><div dir="ltr"><div dir="ltr"><div style="font-size:small"><div dir="ltr"><div dir="ltr"><div dir="ltr"><div dir="ltr"><div dir="ltr"><div dir="ltr"><div dir="ltr"><div dir="ltr"><div style="color:rgb(0,0,0);font-family:"times new roman","new york",times,serif"><font face="times new roman, new york, times, serif"><b>Roozbeh Valavi</b></font></div><div style="color:rgb(0,0,0);font-family:"times new roman","new york",times,serif">PhD Candidate<br></div><div style="color:rgb(0,0,0);font-family:"times new roman","new york",times,serif"><font face="times new roman, new york, times, serif" size="2"><a href="http://qaeco.com/" rel="nofollow" style="color:rgb(25,106,212)" target="_blank">The Quantitative & Applied Ecology Group</a><br></font></div><div style="color:rgb(0,0,0);font-family:"times new roman","new york",times,serif"><font face="times new roman, new york, times, serif" size="2">School of BioSciences | Faculty of Science</font></div><div style="color:rgb(0,0,0);font-family:"times new roman","new york",times,serif"><font face="times new roman, new york, times, serif" size="2">The University of Melbourne,</font> VIC 3010, Australia</div><div style="color:rgb(0,0,0);font-family:"times new roman","new york",times,serif">Mobile: +61 423 283 238<br></div></div></div></div></div></div></div></div></div></div></div></div></div></div></div></div></div></div>
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