To create contours in a unit other than that of the z-values, set an appropriate value for the z-factor. With the default value of 1, the contours will be in the same units as the z-values of the input raster. The contour lines are generated based on the z-values in the input raster, which are often measured in units of meters or feet. The unit conversion factor used when generating contours. You can avoid this shift by using the input raster for the Snap Raster environment. Consequently, the output features will shift as well, and the resultant output features may not overlay the original input raster exactly. This shift will trigger a resampling of the input raster using the Bilinear method. If the Extent environment is specified and the lower left corner of the output extent does not match any cell corner of the input raster, a shift of the cell alignment of the input raster will occur during processing to match the specified extent. To use fewer cores, use the Parallel Processing Factor environment setting. The maximum number of cores that can be used is four. This should only be used when output features would contain a very large number of vertices (many millions).īy default, this tool will take advantage of multicore processors. The vertex limit parameter can be used to subdivide a feature. If you do encounter any problems, setting this parameter to a large value, such as 1 million, may alleviate issues due to the size of a feature. Most modern machines running 64-bit software do not typically have issues with individual features containing hundreds of thousands or millions of vertices. This parameter is intended as a way to subdivide extremely large features that can cause issues later on, for example, when storing, analyzing, or drawing the features.Ĭhoosing a limit is dependent on the available memory on the machine where the tool is being run and the size of the feature (larger features require more memory). This parameter produces similar output to that created by the Dice tool. This should only be used when output features would contain a very large number of vertices (many millions). The Maximum vertices per feature parameter can be used to subdivide a feature. The Contour shell up option creates three overlapping polygons between 0-575, 250-575, and 500-575. The Contour shell option creates three overlapping polygons between 0-575, 0-500, and 0-250.ĬONTOUR_SHELL_UP-Overlapping polygons between 0-575, 250-575, and 500-575 (Fig. CONTOUR_SHELL-Overlapping polygons between 0-575, 0-500, and 0-250 (Fig.The Contour polygon option creates three nonoverlapping polygons between 0-250, 250-500, and 500-575. The actual output is presented, as well as the individual component polygons separately. For example, if you have a raster with values between 0 and 575 and your contour interval is 250, the following are the various output feature classes that will be created. Specifying a base contour does not prevent contours from being created above or below that value.Ĭontour type is used to produce either contour lines or polygons. The values to be contoured are 10, 25, 40, 55, and so on. In this case, 10 is used for the base contour and 15 is the contour interval. If you have the ArcGIS Spatial Analyst extension, smoother but less accurate contours can be obtained by preprocessing the input raster using the Focal Statistics tool with the Mean option or the Filter tool with the Low option.Ī base contour is used, for example, to create contours every 15 meters, starting at 10 meters. Negative contour intervals are not allowed. The contour values will be negative in such areas. However, the contour polygons are extrapolated to the outer edge of the raster when Contour type is not equal to Contour.Ĭontours can be generated in areas of negative raster values. As an alternative to edgematching, you can merge the adjacent rasters before computing contours. Edgematch adjacent contour inputs into a continuous feature dataset first. Contours do not extend beyond the spatial extent of the raster, and they are not generated in areas of NoData.
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