Partition methods#
A partition divides a raster into parts, for upstream accumulation in processes. It
is an optional feature: install it with pip install pyflwdir[partition].
FlwdirRaster.partition() divides the raster into one part a process and
returns a partition.PartitionPlan: the part of each cell, the cell count of
each part, and the opened mainstem sections, which the accumulation finishes last.
partition.partition_plan() is the function behind it.
Upstream accumulation is the only computation that uses a plan: pass it as
partition_plan to FlwdirRaster.accuflux() or
FlwdirRaster.upstream_area(), with parallel=True. The accumulation
checks the plan against the flow directions first, and one plan serves any number of
calls. Making a plan does not make any other method run in parallel.
A tributary subtree is never cut, so the heaviest part is at least as heavy as the largest subtree of an opened basin, however many parts are asked.
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Divide a raster into parts, and return how the opened mainstems connect to them. |
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How the cells of a raster divide over processes, from |
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The cells of one opened mainstem that are accumulated after the parts. |