Falha no Viewshed 2 quando o Tipo de Análise é Observer

Question

<\/HEAD>Quando faço uma análise Viewshed 2 com o tipo de Análise definido como Observer, recebo um erro: "A tabela não foi encontrada. [VAT_Viewshe_dem37]". A análise será executada sem erro se o tipo de análise for definido como frequency. Alguma ideia do que estou fazendo errado?<\/P> <\/P> Obrigado pela ajuda.<\/P> <\/P> Sam<\/P><\/BODY><\/HTML>

SamChan1 · Answer

Here are the associated viewshed 2 results and the VAT.  There appears to be regions visible by multiple observers so I don't understand why the VAT table is showing -1 for observers for all the regions.

DanPatterson_Retired · Answer

a visual of the results and table would help... -1 normally means 'not' as in not seen, can't see or something like that, such as an area can be seen by one observer, but not another and vice versa to differentiate it from areas that can be seen by both

SamChan1 · Answer

Dan. Thanks for the reply. The DEM I am using is a raster dataset. I've looked over the two links you sent and ran Viewshed 2 again using the same inputs that I used previously. There are only 3 points in the input. I first ran it using perimeter sightline and the tool ran successfully. Then I changed it to all sightlines and, again, it ran successfully. I am fairly certain that I did not do anything differently other than the analysis method. So although I am able to get viewshed 2 to work, it is annoying that I don't know why it is working now. The next thing that is puzzling me is the observer value of -1  for all observers in the Value Attribute Table.