urclib.common_utils

Collection of functions that are used in both grid creation and score analyses.

Module Contents

Classes

UrcWorkspace

Manages filepaths associated with a collection of data.

Functions

do_time_capture()	Context which prints the time it took to get from beginning to end of the with block, in seconds.
print_timestamp(raw_seconds)	Print raw seconds in nicely hour, minute, seconds format.
parse_workspace_args(vals, workspace, outputs)	Parse out script arguments into a workspace.
list_fieldnames(featureclass)	Lists the fields in a feature class, shapefile, or table in a specified dataset.
delete_file(path)	Remove a file if present.
raster_domain_intersect(in_coords, in_mask, src_sref, ...)	Create intersect raster for specific field values in vector layer
rasterize(id, fc_list, in_ds, xsize, ysize, geotrans, srs)	Convert specified Vector layers to raster.
index_features(in_lyr, cell_width, cell_height[, ...])	Build a fishnet grid that is culled to existing geometry.
write_raster(mask_lyr, data, name[, drivername, ...])	Write a raster data to a new gdal.Dataset object

Attributes

gdt_np_map
_ogrTypeLabels
_ogrPointTypes
_ogrLineTypes
_ogrPolyTypes
_ogrMultiTypes
_ogrErrLabels
GEOTIFF_OPTIONS

urclib.common_utils.gdt_np_map

urclib.common_utils._ogrTypeLabels

urclib.common_utils._ogrPointTypes

urclib.common_utils._ogrLineTypes

urclib.common_utils._ogrPolyTypes

urclib.common_utils._ogrMultiTypes

urclib.common_utils._ogrErrLabels

urclib.common_utils.GEOTIFF_OPTIONS = ['GEOTIFF_KEYS_FLAVOR=STANDARD', 'TFW=YES']

class urclib.common_utils.UrcWorkspace(workspace_dir=None, **kwargs)

Bases: object

Manages filepaths associated with a collection of data.

workspace

Path to the root directory of the workspace collection; defaults to current working directory.

Type:

str,optional

Parameters:

• workspace_dir (str) – The root directory for the workspace.

• **kwargs – Additional key-path pairs to assign.

__getitem__(item)

Retrieve a path for a given key.

Parameters:

item (str) – The path to retrieve.

Returns:

The requested path.

Return type:

str

Raises:

KeyError – If item does not exist in self.

__setitem__(key, value)

Assign a path to a key.

Parameters:

• key (str) – The key to identify the path with.

• value (str) – The path to assign.

Raises:

ValueError – value is not of type str.

__contains__(item)

__iter__()

__len__()

__delitem__(key)

update(invals)

Update contents of workspaces with that of a dict.

Parameters:

invals (dict) – The content to update the workspace with.

__repr__()

Return repr(self).

keys()

Retrieve the keys for filepaths.

Returns:

The names used to identify individual file paths.

Return type:

dict_keys

items()

Provide Iterator for walking through labels, and associated paths.

Yields:

Tuple – label, and full path, respectively

get(key, default=None)

Retrieve value of key if it exists; otherwise return the default value.

Parameters:

• key (str) – The tag of the path to retrieve.

• default (object,optional) – The default value to pass if a value for key does not exist.

Returns:

The value for key, or the value of default if no value for key exists.

Return type:

object

Raises:

KeyError – if key is not present in the in_workspace and default is None.

delete_files(*args)

Delete the specified files.

Parameters:

*args – List of keys of files to delete.

test_files_exist()

Test each path entry to determine if path exists.

Returns:

(dlg_label,exists) for each entry in REE_workspace, where “exists” is True or False depending on

whether a file is found at location pointed to by associated path.

Return type:

list

exists(key)

Test to see if a given file exists in the filesystem.

Parameters:

key (str) – The dlg_label for the path to query.

Returns:

True if the key and associated file both exist; False otherwise.

Return type:

bool

urclib.common_utils.do_time_capture()

Context which prints the time it took to get from beginning to end of the with block, in seconds.

urclib.common_utils.print_timestamp(raw_seconds)

Print raw seconds in nicely hour, minute, seconds format.

Parameters:

raw_seconds (float) – The raw seconds to print.

urclib.common_utils.parse_workspace_args(vals, workspace, outputs)

Parse out script arguments into a workspace.

Parameters:

• vals (dict) – The arguments to parse.

• workspace (UrcWorkspace) – The destination of any values prefixed with IN_.

• outputs (UrcWorkspace) – The destination of any values prefixed with OUT_.

urclib.common_utils.list_fieldnames(featureclass)

Lists the fields in a feature class, shapefile, or table in a specified dataset.

Parameters:

featureclass (osgeo.ogr.Layer) – Layer to query for field names.

Returns:

The names of each field (as strs).

Return type:

list

urclib.common_utils.delete_file(path)

Remove a file if present.

Parameters:

path (str) – The file to delete, if present.

Returns:

True if file existed and deleted; False if file was not present

Return type:

bool

urclib.common_utils.raster_domain_intersect(in_coords, in_mask, src_sref, join_lyr, fld_name, nodata=-9999)

Create intersect raster for specific field values in vector layer

Parameters:

• in_coords (np.ndarray) – Map from pixel to space coordinates.

• in_mask (np.ndarray) – Raw data from mask layer, with 1 is include, 0 is exclude.

• src_sref (osr.SpatialReference) – The spatial reference to project into.

• join_lyr (ogr.Layer) – The vector layer to parse.

• fld_name (str) – The name of the field to use for indexing.

• nodata (int,optional) – The value to use to represent “no data” pixels. defaults to -9999.

Returns:

index values corresponding to pixel coordinates as defined with inCoords.

Return type:

np.ndarray

urclib.common_utils.rasterize(id, fc_list, in_ds, xsize, ysize, geotrans, srs, drvr_name='mem', prefix='', suffix='', nodata=-9999, gdtype=gdal.GDT_Int32, opts=None)

Convert specified Vector layers to raster.

Parameters:

• id (str) – The id for the new Raster dataset.

• fc_list (list) – A list of list of layers to rasterize.

• in_ds (gdal.Dataset) – The input dataset.

• xsize (int) – The width of the new raster, in pixels.

• ysize (int) – The height of the new raster, in pixels.

• geotrans (tuple) – Matrix of float values describing geographic transformation.

• srs (osr.SpatialReference) – The Spatial Reference System to provide for the new Raster.

• drvr_name (str,optional) – Name of driver to use to create new raster; defaults to “MEM”.

• prefix (str,optional) – Prefix to apply to comp_name for gdal.Dataset dlg_label; this could be a path to a directory if raster is being saved to disk.

• suffix (str,optional) – Suffix to apply to comp_name for gdal.Dataset dlg_label; this could be the file extension if raster is being saved to disk.

• nodata (numeric,optional) – The value to represent no-data in the new Raster; default is -9999

• gdtype (int,optional) – Flag indicating the data type for the raster; default is “gdal.GDT_Int32”.

• opts (list,optional) – String flags to forward to GDAL drivers, if any.

Returns:

The rasterized vector layer.

Return type:

gdal.Dataset

urclib.common_utils.index_features(in_lyr, cell_width, cell_height, drivername='MEM', create_options=None)

Build a fishnet grid that is culled to existing geometry.

Parameters:

• in_lyr (osgeo.ogr.Layer) – The Layer containing the geometry to act as a rough mask.

• cell_width (float) – The width of each cell.

• cell_height (float) – The height of each cell.

• drivername (str,optional) – The driver to use for generating the mask raster. Defaults to MEM.

• create_options (list,optional) – String flags to forward to GDAL drivers, if any.

Returns:

numpy array for coordinate mapping, and gdal.Dataset with masking info.

Return type:

tuple

urclib.common_utils.write_raster(mask_lyr, data, name, drivername='GTiff', gdtype=gdal.GDT_Byte, nodata=-9999)

Write a raster data to a new gdal.Dataset object

Parameters:

• mask_lyr (gdal.Dataset) – Raster object containing mask, dimension, and geotransform information.

• data (np.ndarray) – The data to write to the Dataset

• name (str) – The unique identifier and (depending on the driver) the path to the file to write.

• drivername (str,optional) – The driver to use to create the dataset. Defaults to GTiff.

• gdtype (int,optinal) – The internal data type to use in the generated raster. Defaults to gdal.GDT_Byte.

• nodata (int,optional) – The value to use to represent “no data” pixels. defaults to -9999.

Returns:

Reference to newly created dataset; can be safely ignored if just writing to disk.

Return type:

gdal.Dataset