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Guest luissa

Double check terrain inf file please?

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Could someone double check this terrain inf file for me please?. As far as I can work out this should cover 10 x 6 LOD 11 quads, but the southernmost row is missing.[Destination] LOD = 11 DestDir = "C:My DocumentsNIMA" DestBaseFileName = "LOD11" UseSourceDimensions = 1 [source]Type = ElevS16LSBSourceDir = "C:My DocumentsNIMA"SourceFile = "Lod11.dem"CellType = S16LSBNullCellValue = -9999 Lat = 50.800781828Lon = -1.640625NumOfCellsPerLine = 2561NumOfLines = 1537CellXdimensionDeg = 0.0002288818359375CellYdimensionDeg = 0.00017166137890625ScaleinMeters = 1.0Thanks, David

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Hi David,Latitude boundaries for LOD11 cells are given, EXACTLY, by:N * 90 / ( 2 exp 11 )where N is an integer. Writing N in one column of an Excel file and the the above formula in the adjacent column, you will get:1157 50.844726561156 50.800781251155 50.756835941154 50.712890631153 50.668945311152 50.6251151 50.581054691150 50.537109381149 50.49316406You see that Lat = 50.800781828 is not a LOD11 latitude boundary. Assuming you are using the OLD resampler your Lat = 50.800781828 will cause the resampler to generate data from 50.80078125 to the south.Now your 3 statements in the source section:Lat = 50.800781828NumOfLines = 1537CellYdimensionDeg = 0.00017166137890625are equivalent to the following 2 statements (instead of UseSourceDimensions) in the destination section:NorthLat = 50.800781828Southlat = 50.800781828 - ( 1537 - 1 ) * 0.00017166137890625which is:NorthLat = 50.800781828Southlat = 50.5364063 Therefore your "implicit" SouthLat is not, again, a LOD11 latitude boundary. Looking to the Excel values above you will see that the (OLD) resampler will stop to generate data at latitude 50.58105469.In conclusion: with the given INF you will generate data from latitudes: 50.58105469 up to 50.80078125; in other words: the generated data will span 5 LOD11 quadrants of latitude, not 6!Kind Regards,Luis

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Thanks for the reply Luis, but I cant get the spreadsheet to work.In the formula I get an error, how should the formula be entered:N * 90 / ( 2 exp 11 )should it have a function after the "2" and the "11" bracketed?I took my coords from the SDK, Lat Deg Boundries (LOD11) = 0.043945313, then 0.043945313 * 1156 = 50.800781828Thanks David

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>Thanks for the reply Luis, but I cant get the spreadsheet to >work. >In the formula I get an error, how should the formula be >entered: >>N * 90 / ( 2 exp 11 ) >>should it have a function after the "2" and the "11" >bracketed? >>I took my coords from the SDK, Lat Deg Boundries (LOD11) = >0.043945313, then 0.043945313 * 1156 = 50.800781828 >>Thanks David Hello David,In the SDK docs you have (the following is copy & paste fromthe SDK) this:10 38.2 0.08789062511 19.1 0.04394531312 09.6 .021972656There is a truncation from LOD10 to LOD11. The boundary for LOD11 should be one half of the boundary for LOD10. Therefore: 0.087890625 / 2 = 0.0439453125and: 0.0439453125 * 1156 = 50.80078125But you can avoid this if you use a spreadsheet. In the formula (2 exp 11) is exponentiation (2 to the power of 11). I am sorry for not being so clear in my previous message.Kind Regards, Luis

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