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My challenge is to create a map showing the propagation of waves, similar to sound waves, from their source point, by marking 'contours' of certain intensity at predetermined distances. I have managed this by simply creating buffers at these distances. However, it has additionally been requested that the 'contours' now account for surrounding buildings and infrastructure which will attenuate the waves more quickly. I have created a cost surface based on the level of attenuation provided by the surrounding features. However, I would like to know if there is a way to use the distance/cost path tools to force a process whereby the raster calculates radially out from a point and stops when a certain value has been cumulatively attained by all the cells it has crossed. Otherwise, is there any software which could be used for a similar purpose which is compatible with GIS and could be used and/or any other solutions within arctoolbox.

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Based on your cost distance raster (spatial analyst > distance > cost distance), you can create contour lines using the "contour" tool in spatial analyst > Surface toolbox. Then you can create polygons from those contour lines using "feature to polygon"

You can also modify the symbology of the raster using predefined intervals to visualize your area within a given cost (set colours to null for the class out of your cost of interest) or you can directly set the maximum cost distance in the tools parameters.

  • My issue is that I need it to be contouring based on a cumulative sum across the raster from the source. Aka; if the source point is in the centre and every cell has a value of 1. I need a contour at 100, which will work out from that central point in all directions and stop having crossed 100 cells. Or if 50 of the cells it crosses have a value of 1 and then it crosses cells with a value of 2, it should stop at 75 cells, where the sum total cell value traversed is 100. – Ellen Sep 7 '16 at 13:17
  • I tought that you add the layer already, see my edit with the location of the cost distance tool – radouxju Sep 7 '16 at 13:19
  • I have a raster, with an attribute that determines the value of each cell. But in the hypothetical values are between 1 and 2 and the contours are at a minimum value of 100. It has to be cumulative across the surface to stop at a predetermined sum total, not between 2 set points, and it can't use the in place cost surface raster values because they determine only the value of their own cell, not any of those that the 'sound waves' would already have traversed. – Ellen Sep 7 '16 at 13:27
  • I really think that cost distance is the tool that you need. you can specify a maximum distance if you want. – radouxju Sep 7 '16 at 13:44
  • I'm testing the theory now. I think you may be right. The word reclassify somehow made it click. I was thinking about cost path too closely. I'll let you know if I get it to work. Thanks for all your help. – Ellen Sep 7 '16 at 13:51

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