pysiral.l1preproc.procitems

This module contains the basic functionality of Level-1 (pre-)processor items.

A processor item is a class that is allowed to modify the Level-1 data object and can be called at different stages of the Level-1 pre-processor loop. The classes are initialized when the Level-1 processor is started and thus are allowed to map larger data sets to memory which are then applied for each Level-1 data set.

Processing items can be anywhere in the pysiral namespace, but must inherit pysiral.l1preproc.procitems.L1PProcItem and overwrite the apply(l1) method, which receives the Level-1 data object as input.

Level-1 processor items are instanced from the Level-1 pre-processor definition file (located in pysiral/resources/pysiral-cfg/proc/l1) and require an entry according to this format:

```yaml level1_preprocessor:

…

options:

…

processing_items:

label: <Label displayed in the log file> stage: <stage name (see below)> module_name: <the module where the class is located> class_name: <class name> options:

<custom option dictionary (can be nested)>

```

The value (stage name) supplied to stage defined whne the processing item is run in the main loop of the Level-1 pre-processor. Following options are currently implemented:

The processing item will be applied to the Level-1 data object, which is has the same extent as the source file (stage=`post_source_file`).
The processing item will be applied to a list of all polar ocean segments of a source file (stage=`post_ocean_segment_extraction`). This option is recommended for computation intensive processing items.
The processing item will be applied to the merged polar ocean segment (stage=`post_merge`)

Attributes

L1PPROCITEM_CLS_TYPE

Classes

`L1PProcItem`
`L1PProcItemDef`	Class for validating and processing Level-1 Pre-Processor item definition

Functions

get_l1_proc_item(→ L1PPROCITEM_CLS_TYPE)

A function returning an initialized processor item class

Module Contents

class pysiral.l1preproc.procitems.L1PProcItem(**cfg: Dict)

Bases: object

cfg

abstractmethod apply(l1: pysiral.l1data.Level1bData): Mandatory class for Level-1 processing item. Needs to be overwritten by the inheriting class. :param l1: :return:

__getattr__(item: str) → Any

Direct attribute access to the cfg dictionary. Required for historical reasons and readable code.

Parameters:: item
Returns:

pysiral.l1preproc.procitems.L1PPROCITEM_CLS_TYPE

class pysiral.l1preproc.procitems.L1PProcItemDef(label: str, stage: str, module_name: str, class_name: str, options_dict: dict = None)

Bases: object

Class for validating and processing Level-1 Pre-Processor item definition

label

stage

module_name

class_name

option_dict

classmethod from_l1procdef_dict(procdef_dict: dict | pysiral.core.legacy_classes.AttrDict) → L1PProcItemDef: Initialize the class from the corresponding excerpt of the Level-1 processor configuration file. :param procdef_dict: :return:

get_initialized_processing_item_instance() → L1PPROCITEM_CLS_TYPE

Return an inialized instance of the processor item described by this configuration class

Returns:: descendent of L1PProcItem

property valid_stages

pysiral.l1preproc.procitems.get_l1_proc_item(module_name: str, class_name: str, **cfg: Dict) → L1PPROCITEM_CLS_TYPE

A function returning an initialized processor item class

Parameters:

module_name
class_name
cfg

Returns:

The initialized processor item class

Raises:

ValueError