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    <p>One simple and somewhat inaccurate way to do this would be to decrease the granularity of your data. It might not even be inaccurate, depending on how accurate your x, y measurements are.</p> <p>let's say we have the following data:</p> <pre><code>x y signal_strenth 10.2 5.1 10 10.1 5.3 12 10.3 5.5 8 </code></pre> <p>If we floor the x and y values, we get:</p> <pre><code>x y signal_strenth 10 5 10 10 5 12 10 5 9 </code></pre> <p>Then we can average those values by the floored x and y to show that we have average signal strength in the rectangle (10, 5) to (11, 6).</p> <p>Here's the SQL:</p> <pre><code>select floor(x) as rectangle_xmin, floor(y) as rectangle_ymin, floor(x) + 1 as rectangle_xmax, floor(y) + 1 as rectangle_ymax, avg(signal_strength) as signal_strength from table group by floor(x), floor(y); </code></pre> <p>Now, admittedly, you'd ideally want to group data points by distance from point to point, and this groups them by a maximum distance that varies from 1 and to square_root(2) =~1.44, flooring them into rectangular blocks. So it's less than <em>ideal</em>. But it may work well enough for you, especially if the flooring/grouping is less than the error in your measurement of position.</p> <p>If <code>floor()</code> is not granular enough, you can use <code>floor( x *</code> someweight<code>) /</code> someweight to adjust it to the granularity you want. And of course you can use <code>ceil()</code> or <code>round()</code> to do the same thing. </p> <p>The whole point is to <em>collapse</em> a bunch of nearby measurements to one "measurement", and then take the average of the collapsed values.</p>
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    1. POAveraging data for points in close proximity with SQL Server 2008
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    1. COThis isn't a bad idea at all... like you say it's not the ideal solution but it may work. As these are GPS co-ordinates floor(x) would not be granular enough but floor(x * 100) might be. I'll give it a go and see what the data looks like.
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    2. COOk, it works. There is some accuracy lost but it greatly reduces the amount of data for when the devices aren't moving so that Virtual Earth can keep up. Thanks! I've altered it slightly so I'll post it here for anyone who comes across this.
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