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How are contour lines generated in ArcGIS help?
The contour lines are generated based on the z-values in the input raster, which are often measured in units of meters or feet. With the default value of 1, the contours will be in the same units as the z-values of the input raster.
How are contours generated from a raster surface?
Creates a line feature class of contours (isolines) from a raster surface. Contours do not extend beyond the spatial extent of the raster, and they are not generated in areas of NoData; therefore, adjacent contour inputs should first be edgematched into a continuous feature dataset.
Which is the output of the contour function?
Output options include contour lines, index contours, and filled contours. The creation of a contour layer as a raster product is valuable for a wide range of applications since the contours can be overlaid on a map and provide information regarding the terrain without obscuring the underlying data.
What happens when contour is set to smooth only?
When Contour Type is set to Contour smooth only, the input elevation layer is smoothed using the adaptive filter but does not produce contours. The smoothed output layer can then be exported and input to a variety of tools in the Raster Surface toolset or a vector Contour tool.
What are the tools used to create contours?
The contour creation tools, Contour, Contour List and Contour with Barriers, are used to create a polyline feature dataset from an input raster. Why create contours? By following the polyline of a particular contour, you can identify which locations have the same value.
What is the current version of contour with barriers?
The current version of Contour with Barriers only supports polyline output. If the polygon output option is used it will be ignored and polyline output will be created. Smoother but less accurate contours can be obtained by preprocessing the input raster with a Focal Statistics operation with the MEAN option or the Filter tool with the LOW option.
Are there any open source alternatives to ArcGIS?
Libraries like GDAL/OGR provide base functionality to many other spatially enabled programs and have bindings for many popular programming languages. Projects like GeoServer and MapServer offer server-side spatial data hosting. Many of these open source projects find commercial support from companies like Boundless.
Which is the upper bound of a contour shell?
CONTOUR_SHELL_UP —A polygon feature class in which the lower bound of the polygon increases cumulatively, from the raster minimum, by the interval value. The upper bound remains constant at the raster maximum. The vertex limit when subdividing a feature.
When to use base contour and contour interval?
A base contour is used, for example, to create contours every 15 meters, starting at 10 meters. In this case, 10 is used for the base contour and 15 is the contour interval. The values to be contoured are 10, 25, 40, 55, and so on.
How many overlapping polygons are there in contour shell?
The Contour shell option creates three overlapping polygons between 0-575, 0-500, and 0-250. CONTOUR_SHELL_UP —Overlapping polygons between 0-575, 250-575, and 500-575 (Fig. 3) Figure 3. The Contour shell up option creates three overlapping polygons between 0-575, 250-575, and 500-575.