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46 lines
1.2 KiB
ReStructuredText
46 lines
1.2 KiB
ReStructuredText
CONVERGENCE INDEX
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=================
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Description
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-----------
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It calculates an index of convergence/divergence regarding to overland flow.
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By its meaning it is similar to plan or horizontal curvature, but gives much smoother results.
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The calculation uses the aspects of surrounding cells, i.e. it looks to which degree surrounding cells point to the center cell.
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The result is given as percentages, negative values correspond to convergent, positive to divergent flow conditions.
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Minus 100 would be like a peak of a cone, plus 100 a pit, and 0 an even slope.
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Parameters
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----------
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- ``Elevation[Raster]``:
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- ``Method[Selection]``:
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- ``Gradient Calculation[Selection]``:
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Outputs
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-------
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- ``Convergence Index[Raster]``:
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See also
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---------
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Koethe, R. / Lehmeier, F. (1996): 'SARA, System zur Automatischen Relief-Analyse', Benutzerhandbuch, 2. Auflage
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[Geogr. Inst. Univ. Goettingen, unpublished]
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Console usage
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-------------
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::
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processing.runalg('saga:convergenceindex', elevation, method, neighbours, result)
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Available options for selection parameters:
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method(Method)
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0 - [0] Aspect
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1 - [1] Gradient
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neighbours(Gradient Calculation)
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0 - [0] 2 x 2
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1 - [1] 3 x 3
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