TableWriter

class ctapipe.io.TableWriter(**kwargs: Any)

Bases: ctapipe.core.component.Component

Base class for writing tabular data stored in Container

A single write will add a new row to the output table, where each Field becomes a column. Subclasses of this implement specific output types.

See also

ctapipe.io.HDF5TableWriter

Implementation of this base class for writing HDF5 files

Methods Summary

add_column_transform(table_name, col_name, …)	Add a transformation function for a column.
add_column_transform_regexp(table_regexp, …)	Add a transformation function for a set of columns and tables that match the given regular expressions.
close()	Close open writer
exclude(table_regexp, pattern)	Exclude any columns (Fields) matching the pattern from being written.
open(filename, **kwargs)	open an output file
write(table_name, containers, **kwargs)	Write the contents of the given container or containers to a table.

Methods Documentation

add_column_transform(table_name, col_name, transform)

Add a transformation function for a column. This function will be called on the value in the container before it is written to the output file.

Parameters

table_name: str

identifier of table being written

col_name: str

name of column in the table (or item in the Container).

transform: ColumnTransform

function that tranforms input into output

add_column_transform_regexp(table_regexp, col_regexp, transform)

Add a transformation function for a set of columns and tables that match the given regular expressions. Each requested transform pattern will be turned into an explicit column transform when the table schema is built.

Parameters

table_name: regexp

pattern matching the table name (via re.matchall)

col_name: regexp

pattern matching the column name if the table name also matches (via re.matchall)

transform: ColumnTransform

function that tranformns input value into output value

abstract close()

Close open writer

exclude(table_regexp, pattern)

Exclude any columns (Fields) matching the pattern from being written. The patterns are matched with re.fullmatch.

Parameters

table_regexp: str

regexp matching to match table name to apply exclusion

pattern: str

regular expression string to match column name in the table

abstract open(filename, **kwargs)

open an output file

Parameters

filename: str

output file name

kwargs:

any extra args to pass to the subclass open method

abstract write(table_name, containers, **kwargs)

Write the contents of the given container or containers to a table. The first call to write will create a schema and initialize the table within the file. The shape of data within the container must not change between calls, since variable-length arrays are not supported.

Parameters

table_name: str

name of table to write to

containers: ctapipe.core.Container or iterable thereof

container instance(s) to write

**kwargs:

may be passed to a lower level implementation to set options