K-nearest neighbour joins from the Processing toolbox!
This algorithm takes an input vector layer and creates a new
vector layer that is an with additional attributes in its attribute table
The additional attributes and their values are taken from a second
vector layer, where features are joined by finding the closest features
from each layer.
By default only the single nearest feature is joined, but optionally
the join can use the n-nearest neighboring features instead.
If a maximum distance is specified, then only features which are
closer than this distance will be matched.
Adds X and Y (or latitude/longitude) fields to a point layer.
The X/Y fields can be calculated in a different CRS to the
layer (e.g. creating latitude/longitude fields for a layer in
a project CRS).
Sponsored by SMEC/SJ
Even though not all errors are caught by these new tests, it could
expose if otb is broken or if processing api is changed to adopt
optional status of parameters at run-time.
`alg.processAlgorithm()` is running and failing correctly.
But `parameter.checkValueIsAcceptable()` and `alg.checkParameterValues()`
aren't working as expected.
These algorithms calculate the boolean OR or AND for a set of input
rasters. For AND, if all of the input rasters have a non-zero value
for a pixel, that pixel will be set to 1 in the output raster, otherwise
it will be set to 0. For OR, if ANY of the input rasters have a non-zero
value for a pixel, that pixel will be set to 1 in the output raster,
else 0.
A reference layer parameter specifies an existing raster layer to use
as a reference when creating the output raster. The output raster will
have the same extent, CRS, and pixel dimensions as this layer
By default, a nodata pixel in ANY of the input layers will result in
a nodata pixel in the output raster. If the 'Treat nodata values
as false' option is checked, then nodata inputs will be treated the
same as a 0 input value.
Makes for much simpler raster boolean logic calculation without
the complexity of using the raster calculator (and that's not
always possible to do anyway, e.g. when ANY of the input rasters
has a nodata pixel). It's also scalable dynamic to any number of
input rasters (unlike raster calc), so is more flexible when
used within models.
causing rings errors
By default the algorithm now uses the strict OGC definition of polygon validity, where
a polygon is marked as invalid if a self-intersecting ring causes an interior hole.
If the "Ignore ring self intersections" option is checked, then this rule will be
ignored and a more lenient validity check will be performed.
Refs #16418, refs #21336
This can easily go into GuiTests.py but we tend to keep it out due to
usage of create_from_metadata(). All widget in GuiTests uses
create_from_class() which will not work for this special widget
of main algorithm
Using code like:
buffered_layer = processing.run(..., context, feedback)['OUTPUT']
...
return {'OUTPUT': buffered_layer}
can cause issues if done as a sub-step of a larger processing algorithm. This
is because ownership of the generated layer is transferred to the caller
(Python) by processing.run. When the algorithm returns, Processing
attempts to move ownership of the layer from the context to the caller,
resulting in a crash.
(This is by design, because processing.run has been optimised for the
most common use case, which is one-off execution of algorithms as part
of a script, not as part of another processing algorithm. Accordingly
by design it returns layers and ownership to the caller, making things
easier for callers as they do not then have to resolve the layer reference
from the context object and handle ownership themselves)
This commit adds a new "is_child_algorithm" argument to processing.run.
For algorithms which are executed as sub-steps of a larger algorithm
is_child_algorithm should be set to True to avoid any ownership issues
with layers. E.g.
buffered_layer = processing.run(..., context, feedback, is_child_algorithm=True)['OUTPUT']
...
return {'OUTPUT': buffered_layer}
Instead of requiring clients to generate temporary file names themselves,
(or use the cryptic "memory:" string!), this PR adds a static constant
QgsProcessing.TEMPORARY_OUTPUT
If a layer/sink output parameter is set to QgsProcessing.TEMPORARY_OUTPUT,
then the temporary output filename will be generated automatically at
algorithm run time. This means callers don't need to mess around with
finding appropriate temporary folders and paths.
Another benefit is that TEMPORARY_OUTPUT is stored in the processing
history, so if you re-run a previous algorithm which was set to
output to a temporary file, it no longer tries to use that same
previous temporary path and instead generates a new one.
