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I have an input boundary vector layer (700 hectares); on it, I want to generate a set of random points (Vector/Research tools/Random points) with a reciprocal distance average of 233 meters, but the smallest density I manage to set is 0,0001 (which is, as it looks to me, an average of 100 meters distance). enter image description here

Does someone have any clue?

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Given a polygon of approximately 800 hectares in the same CRS as yours, a points density of 0.0001 points/meter yields the following:

nearest neighbor analysis

This is obviously too dense, as you've found. It should be noted that in newer versions of QGIS, it's possible to set your density parameter with much finer precision. Here is the same area, with a density parameter of 0.000005:

enter image description here

Which gives a mean distance of 235, very close to what you're looking for. Given the limitations you're facing, though, it's still possible to calculate an equivalent result without changing versions.

density calculation

Given that your area is known, you can calculate the number of points equivalent to smaller density values, and enter the result under the Points count sampling strategy.

In this case, the area of my polygon * 0.000005 = 40.19. Entering 40 for the number of points yields the following:

nearest neighbor 3

Over a number of iterations, the results of points count and points density are more or less indistinguishable from one another.

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