NoiseMap Forums

NoiseMap Software => Support => Topic started by: roger on January 30, 2013, 11:00:30 PM

Title: Too Many Possible Barriers - Excess Excluded with loss of accuracy
Post by: roger on January 30, 2013, 11:00:30 PM

Why is my model giving me the above Warning message and what should I do about it?

This error occurs when there are a large number of barriers within the angle of view of a road segment.
It stems from the days when computers had limited memory and calculation speed and NoiseMap would only consider the first 100 barriers within the angle of view of any road segment.  In NoiseMap five, you can now set the maximum number of barriers within the angle of view of any road segment to several thousand, using the Edit Calculation Parameters dialog.

In NoiseMap Enterprise (NoiseMap 2000) it can be eliminated by using shorter road segments or fewer barriers, but in general it does not cause a significant loss of accuracy.

However, often you can disregard the message, as long as you first check to ensure that the results seems to be about right, in other words that no barrier screening seems to be missing.