Frames¶

PgxFrame and other classes related to frames.

class pypgx.api.frames.DataTypes¶

Bases: object

This class can be used to construct parametrized data types (e.g., VectorType).

static vector(componenttype, dimension)¶

Create and return a new VectorType.

Parameters

componenttype (str) –
dimension (int) –

Return type

pypgx.api.frames._pgx_data_types.VectorType

class pypgx.api.frames.PgxCsvFrameReader(java_pgx_csv_frame_reader)¶

Bases: object

Class for reading PgxFrame objects from CSV files.

Return type: None

auto_detect_columns(auto_detect)¶

Enable or disable the autodetection of columns from the table.

Executing this function clears the currently loaded column descriptors.

Parameters: auto_detect (bool) – True if the columns should be autodetected, False otherwise
Returns: self
Return type: pypgx.api.frames._pgx_frame_reader.PgxCsvFrameReader

clear_columns()¶

Clear the current configuration of which columns should be loaded and how.

Returns: None
Return type: None

columns(column_descriptors)¶

Set the columns to be loaded from their columnDescriptors.

Parameters: column_descriptors (List[Tuple[str, str]]) – List of tuples (columnName, columnType)
Returns: self
Return type: pypgx.api.frames._pgx_frame_reader.PgxCsvFrameReader

load(uris)¶

Load a PgxFrame from the provided URIs.

Parameters: uris (str) – the URIs from which to load the frame
Returns: PgxFrame instance
Return type: pypgx.api.frames._pgx_frame.PgxFrame

load_async(uris)¶

Load a PgxFrame from the provided URIs.

Parameters: uris (str) – the URIs from which to load the frame
Returns: PgxFrame instance

name(frame_name)¶

Set the frame name.

Parameters: frame_name (str) – New name for the PgxFrame
Returns: self
Return type: pypgx.api.frames._pgx_frame_reader.PgxCsvFrameReader

separator(sep)¶

Set the separator for CSV parsing to sep.

Parameters: sep (str) – char denoting the separator
Returns: self
Return type: pypgx.api.frames._pgx_frame_reader.PgxCsvFrameReader

class pypgx.api.frames.PgxCsvFrameStorer(java_pgx_csv_frame_storer)¶

Bases: object

Class for configuring the storing operation of a PgxFrame to a CSV file and then triggering it.

Return type: None

clear_columns()¶

Clear columns

Returns
Return type: None

columns(column_descriptors)¶

Set columns

Parameters: column_descriptors (List[Tuple[str, str]]) – List of tuples (columnName, columnType)
Returns
Return type: pypgx.api.frames._pgx_frame_storer.PgxCsvFrameStorer

name(frame_name)¶

Set the frame name.

Parameters: frame_name (str) – frame name.
Returns: this storer
Return type: pypgx.api.frames._pgx_frame_storer.PgxCsvFrameStorer

overwrite(overwrite_bool)¶

Set overwrite

Parameters: overwrite_bool (bool) – denotes if the table should be overwritten.
Returns
Return type: pypgx.api.frames._pgx_frame_storer.PgxCsvFrameStorer

partition_extension(file_extension)¶

Set the fileExtension of the created CSV files.

Parameters: file_extension (str) – string denoting the file extension for the created files.
Returns: this storer
Return type: pypgx.api.frames._pgx_frame_storer.PgxCsvFrameStorer

partitions(num_partitions)¶

Set the number of files to be created.

Parameters: num_partitions (int) – number of partitions created.
Returns: this storer
Return type: pypgx.api.frames._pgx_frame_storer.PgxCsvFrameStorer

separator(sep)¶

Set the separator for CSV file to sep.

Parameters: sep (str) – char denoting the separator
Returns: self
Return type: pypgx.api.frames._pgx_frame_storer.PgxCsvFrameStorer

store()¶

Store PgxFrame

Returns: PgxFrame instance
Return type: None

store_async()¶

Store PgxFrame

Returns: PgxFrame instance

table_name(table_name)¶

Set the table name in the database.

Parameters: table_name (str) – nodes table name.
Returns: this storer
Return type: pypgx.api.frames._pgx_frame_storer.PgxCsvFrameStorer

class pypgx.api.frames.PgxDbFrameReader(java_pgx_db_frame_reader)¶

Bases: object

Class for reading PgxFrame objects from a database.

Return type: None

auto_detect_columns(auto_detect)¶

Enable or disable the autodetection of columns from the table.

Executing this function clears the currently loaded column descriptors.

Parameters: auto_detect (bool) – True if the columns should be autodetected, False otherwise
Returns: self
Return type: pypgx.api.frames._pgx_frame_reader.PgxDbFrameReader

clear_columns()¶

Clear the current configuration of which columns should be loaded and how.

Returns: None
Return type: None

columns(column_descriptors)¶

Set the columns to be loaded from their columnDescriptors.

Executing this function disables autodetection of columns.

Parameters: column_descriptors (List[Tuple[str, str]]) – List of tuples (columnName, columnType)
Returns: self
Return type: pypgx.api.frames._pgx_frame_reader.PgxDbFrameReader

connections(connections)¶

Set the number of connections to read/write data from/to the database provider

Parameters: connections (int) – number of connections
Returns: self
Return type: pypgx.api.frames._pgx_frame_reader.PgxDbFrameReader

data_source_id(data_source_id)¶

Set the datasource ID.

Parameters: data_source_id (str) – the datasource ID
Returns: self
Return type: pypgx.api.frames._pgx_frame_reader.PgxDbFrameReader

jdbc_url(jdbc_url)¶

Set the jdbc URL to use for connecting to the DB.

Parameters: jdbc_url – the jdbc URL
Returns: self

keystore_alias(keystore_alias)¶

Set the keystore alias.

Parameters: keystore_alias – the keystore alias.
Returns: self

load()¶

Load a PgxFrame from the database.

Parameters: uris – the URIs from which to load the frame
Returns: PgxFrame instance
Return type: pypgx.api.frames._pgx_frame.PgxFrame

load_async()¶

Load a PgxFrame from the database.

Parameters: uris – the URIs from which to load the frame
Returns: PgxFrame instance

name(frame_name)¶

Set the frame name.

Parameters: frame_name (str) – New name for the PgxFrame
Returns: self
Return type: pypgx.api.frames._pgx_frame_reader.PgxDbFrameReader

owner(owner)¶

Set the owner of the table.

Parameters: owner (str) – the owner
Returns: self
Return type: pypgx.api.frames._pgx_frame_reader.PgxDbFrameReader

password(password)¶

Set the password of the database.

Parameters: password (str) – the password
Returns: self
Return type: pypgx.api.frames._pgx_frame_reader.PgxDbFrameReader

schema(schema)¶

Set the schema of the table.

Parameters: schema (str) – the schema.
Returns: self
Return type: pypgx.api.frames._pgx_frame_reader.PgxDbFrameReader

table_name(table_name)¶

Set the table name in the database.

Parameters: table_name (str) – nodes table name.
Returns: self
Return type: pypgx.api.frames._pgx_frame_reader.PgxDbFrameReader

username(username)¶

Set the username of the database.

Parameters: username (str) – username
Returns: self
Return type: pypgx.api.frames._pgx_frame_reader.PgxDbFrameReader

class pypgx.api.frames.PgxDbFrameStorer(java_pgx_db_frame_storer)¶

Bases: object

Class for configuring the storing operation of a PgxFrame to a database and then triggering it.

Return type: None

clear_columns()¶

Clear columns

Returns: self
Return type: None

columns(column_descriptors)¶

Set columns

Parameters: column_descriptors (List[Tuple[str, str]]) – List of tuples (columnName, columnType)
Returns: self
Return type: pypgx.api.frames._pgx_frame_storer.PgxDbFrameStorer

connections(connections)¶

Set the number of connections to read/write data from/to the database provider

Parameters: connections (int) – number of connections
Returns: this storer
Return type: pypgx.api.frames._pgx_frame_storer.PgxDbFrameStorer

data_source_id(data_source_id)¶

Set the datasource ID.

Parameters: data_source_id (str) – the datasource ID
Returns: this storer
Return type: pypgx.api.frames._pgx_frame_storer.PgxDbFrameStorer

jdbc_url(jdbc_url)¶

Set jdbc url

Parameters: jdbc_url (str) –
Returns
Return type: pypgx.api.frames._pgx_frame_storer.PgxDbFrameStorer

keystore_alias(keystore_alias)¶

Set the keystore alias.

Parameters: keystore_alias (str) – the keystore alias.
Returns: this storer
Return type: pypgx.api.frames._pgx_frame_storer.PgxDbFrameStorer

name(frame_name)¶

Set the frame name.

Parameters: frame_name (str) – frame name.
Returns: self
Return type: pypgx.api.frames._pgx_frame_storer.PgxDbFrameStorer

overwrite(overwrite_bool)¶

Set overwrite

Parameters: overwrite_bool (bool) –
Returns: self
Return type: pypgx.api.frames._pgx_frame_storer.PgxDbFrameStorer

owner(owner)¶

Set the owner of the table.

Parameters: owner (str) – the owner
Returns: this storer
Return type: pypgx.api.frames._pgx_frame_storer.PgxDbFrameStorer

password(password)¶

Set the password of the database.

Parameters: password (str) – the password
Returns: this storer
Return type: pypgx.api.frames._pgx_frame_storer.PgxDbFrameStorer

schema(schema)¶

Set the schema of the table.

Parameters: schema (str) – the schema.
Returns: this storer
Return type: pypgx.api.frames._pgx_frame_storer.PgxDbFrameStorer

store()¶

Store the PgxFrame.

Returns: None
Return type: None

store_async()¶

Store the PgxFrame.

Returns: None
Return type: None

table_name(table_name)¶

Set the table name in the database.

Parameters: table_name (str) – nodes table name.
Returns: self
Return type: pypgx.api.frames._pgx_frame_storer.PgxDbFrameStorer

username(username)¶

Set the username of the database.

Parameters: username (str) – username
Returns: this storer
Return type: pypgx.api.frames._pgx_frame_storer.PgxDbFrameStorer

class pypgx.api.frames.PgxFrame(java_pgx_frame)¶

Bases: pypgx.api._pgx_context_manager.PgxContextManager

Data-structure to load/store and manipulate tabular data.

It contains rows and columns. A PgxFrame can contain multiple columns where each column consist of elements of the same data type, and has a name. The list of the columns with their names and data types defines the schema of the frame. (The number of rows in the PgxFrame is not part of the schema of the frame.)

Return type: None

clone()¶

Create a new PgxFrame with the same content as the current frame

Returns: PgxFrame
Return type: pypgx.api.frames._pgx_frame.PgxFrame

close()¶

Free resources on the server taken up by this frame.

Return type: None

property columns: List[str]¶

Get the names of the columns contained in the PgxFrame.

Return type: list

count()¶

Count number of elements in the frame.

Return type: int

destroy()¶

Free resources on the server taken up by this frame.

Return type: None

flatten(*columns, inplace=False)¶

Create a new PgxFrame with all the specified columns and vector columns flattened into multiple columns.

Parameters

columns (str) – Column names
inplace (bool) – Apply the changes inplace and return self

Returns

PgxFrame

flatten_all(inplace=False)¶

Create a new PgxFrame with all nested columns and vector columns flattened into multiple columns.

Parameters: inplace (bool) – Apply the changes inplace and return self
Returns: PgxFrame
Return type: pypgx.api.frames._pgx_frame.PgxFrame

get_column(name)¶

Return a PgxFrameColumn.

Parameters: name (str) – Column name
Returns: PgxFrameColumn
Return type: pypgx.api.frames._pgx_frame.PgxFrameColumn

get_column_descriptors()¶

Return a list containing the description of the different columns of the frames.

Return type: List[Tuple[str, str]]

head(num_rows=10, inplace=False)¶

Return the first num_rows elements of the frame

Parameters

num_rows (int) – Number of rows to take
inplace (bool) – Apply the changes inplace and return self

Returns

PgxFrame

Return type

pypgx.api.frames._pgx_frame.PgxFrame

join(right, join_key_column=None, left_join_key_column=None, right_join_key_column=None, left_prefix=None, right_prefix=None, inplace=False)¶

Create a new PgxFrame by performing a join operation.

Create a new PgxFrame by adding the columns of the right frame to this frame, aligned on equality of entries in column left_join_key_column for this frame and column right_join_key_column for the right frame, or join_key_columns on both frames. The resulting frame will contain the columns of this frame prefixed by left_prefix and the columns of right frame prefixed by right_prefix (if the prefixes are not null). Prefixes must ether not be set or both be set.

Parameters

right (pypgx.api.frames._pgx_frame.PgxFrame) – PgxFrame whose columns will be added to the columns of this PgxFrame
join_key_column (Optional[str]) – Column of both frames on which the equality test will be performed
left_join_key_column (Optional[str]) – Column of this frame on which the equality test will be performed with right_join_key_column
right_join_key_column (Optional[str]) – Column of right frame on which the equality test will be performed with leftJoinKeyColumn
left_prefix (Optional[str]) – Prefix of the columns name of this frame in the resulting frame
right_prefix (Optional[str]) – Prefix of the columns name of right frame in the resulting frame
inplace (bool) – Apply the changes inplace and return self

Returns

PgxFrame

Return type

pypgx.api.frames._pgx_frame.PgxFrame

property length: int¶

Return the number of rows in the frame.

Returns: number of rows

print(file=None, num_results=1000, start=0)¶

Print the frame.

Parameters

file (Optional[TextIO]) – File to which results are printed (default is sys.stdout)
num_results (int) – Number of results to be printed
start (int) – Index of the first result to be printed

Return type

None

rename_column(old_column_name, new_column_name, inplace=False)¶

Return a PgxFrame with the column name modified.

Parameters

old_column_name (str) – name of the column to rename
new_column_name (str) – name of the column after the operation
inplace (bool) – Apply the changes inplace and return self

Returns

PgxFrame

Return type

pypgx.api.frames._pgx_frame.PgxFrame

rename_columns(column_renaming, inplace=False)¶

Return a PgxFrame with the column name modified.

Parameters

column_renaming (Mapping[str, str]) – dict-like holding old_column names as keys and new column names as values
inplace (bool) – Apply the changes inplace and return self

Returns

PgxFrame

Return type

pypgx.api.frames._pgx_frame.PgxFrame

select(*columns, inplace=False)¶

Select multiple columns by column name.

Parameters

columns (str) – Column names
inplace (bool) – Apply the changes inplace and return self

Returns

PgxFrame

Return type

pypgx.api.frames._pgx_frame.PgxFrame

store(path, file_format='csv', overwrite=True)¶

Store the frame in a file.

Parameters

path (str) – Path where to store the frame
file_format (str) – Storage format
overwrite (bool) – Overwrite current file

Return type

None

tail(num_rows=10, inplace=False)¶

Return the last num_rows elements of the frame

Parameters

num_rows (int) – Number of rows to take
inplace (bool) – Apply the changes inplace and return self

Returns

PgxFrame

Return type

pypgx.api.frames._pgx_frame.PgxFrame

to_pandas()¶

Convert to pandas DataFrame.

This method may change result_set cursor.

This method requires pandas.

Returns: PgxFrame as a Pandas Dataframe

to_pgql_result_set()¶

Create a new PgqlResultSet having the same content as this frame.

Returns: PgqlResultSet
Return type: pypgx.api._pgql_result_set.PgqlResultSet

union(*frames, inplace=False)¶

Create a PgxFrame by concatenating the rows of this frame with the rows of the frames in frames. The different frames should have the same columns (same names, types and dimensions), in the same order. The resulting frame is not guaranteed to have any specific ordering of its rows.

Parameters

frames (pypgx.api.frames._pgx_frame.PgxFrame) – Frames tu add through union
inplace (bool) – Apply the changes inplace and return self

Returns

PgxFrame

Return type

pypgx.api.frames._pgx_frame.PgxFrame

write()¶

Get Pgx Frame storer

Returns: PgxGenericFrameStorer
Return type: pypgx.api.frames._pgx_frame_storer.PgxGenericFrameStorer

class pypgx.api.frames.PgxFrameBuilder(java_pgx_frame_builder)¶

Bases: pypgx.api._pgx_context_manager.PgxContextManager

A frame builder for constructing a PgxFrame.

Return type: None

add_rows(column_data)¶

Add the data to the frame builder.

Parameters: column_data (Dict[str, Any]) – the column data in a dictionary
Returns: self
Return type: pypgx.api.frames._pgx_frame_builder.PgxFrameBuilder

build(frame_name)¶

Build the frame with the given frame name.

Parameters: frame_name (str) – the name of the frame to create
Returns: the newly frame created
Return type: pypgx.api.frames._pgx_frame.PgxFrame

close()¶

Free resources on the server taken up by this frame builder. After this method returns, the behaviour of any methods of this class becomes undefined.

Return type: None

destroy()¶

Free resources on the server taken up by this frame builder. After this method returns, the behaviour of any methods of this class becomes undefined.

Return type: None

class pypgx.api.frames.PgxFrameColumn(java_pgx_frame_column)¶

Bases: pypgx.api._pgx_context_manager.PgxContextManager

Class representing one column of a PgxFrame.

Return type: None

close()¶

Destroy/close the object.

Base implementation, overridable by subclasses.

Return type: None

destroy()¶

Free resources on the server taken up by this column.

Return type: None

get_descriptor()¶

Return a description of the column.

Return type: Tuple[str, str]

class pypgx.api.frames.PgxGenericFrameReader(java_pgx_generic_frame_reader)¶

Bases: object

A generic class for reading PgxFrame objects from various sources.

The class allows configuration of how the data should be read and facilitates the creation of specialized frame readers (PgxCsvFrameReader and PgxPgbFrameReader).

Return type: None

auto_detect_columns(auto_detect)¶

Enable or disable the autodetection of columns from the table.

Not all formats support autodetection of the columns (only DB in fact).

Executing this function clears the currently loaded column descriptors.

Parameters: auto_detect (bool) – True if the columns should be autodetected, False otherwise
Returns: self
Return type: pypgx.api.frames._pgx_frame_reader.PgxGenericFrameReader

clear_columns()¶

Clear the current configuration of which columns should be loaded and how.

Returns: None
Return type: None

columns(column_descriptors)¶

Set the columns to be loaded from their columnDescriptors.

Executing this function disables autodetection of columns.

Parameters: column_descriptors (List[Tuple[str, str]]) – List of tuples (columnName, columnType)
Returns: self
Return type: pypgx.api.frames._pgx_frame_reader.PgxGenericFrameReader

csv(uris=None)¶

Create a PgxCsvFrameReader object for loading CSV files from URIs.

Parameters: uris (Optional[str]) – List of paths to the csv files
Return type: PgxCsvFrameReader

csv_async(uris)¶

Read a PgxFrame from a list of URIs to CSV files.

Parameters: uris (str) – list denoting the URIs
Returns: the read frame

db()¶

Create a PgxDbFrameReader object to load PgxFrame from a database.

Return type: PgxDbFrameReader

format(format)¶

Return a frame reader for the type format specified.

Parameters: format (str) – format to be loaded Can be one of ‘csv’ or ‘pgb’
Returns: a loader for the format
Return type: PgxCsvFrameReader or PgxPgbFrameReader

name(frame_name)¶

Set the frame name.

Parameters: frame_name (str) – New name for the PgxFrame
Returns: self
Return type: pypgx.api.frames._pgx_frame_reader.PgxGenericFrameReader

pgb(uris=None)¶

Create a PgxPgbFrameReader object for loading PGB files.

Parameters: uris (Optional[str]) – List of paths to the PGB files
Return type: PgxPgbFrameReader

pgb_async(uris)¶

Read a PgxFrame from a list of URIs to PGB files.

Parameters: uris (str) – list denoting the URIs
Returns: the read frame

class pypgx.api.frames.PgxGenericFrameStorer(java_pgx_generic_frame_storer)¶

Bases: object

Class for configuring the storing operation of a PgxFrame and then triggering it.

Return type: None

csv()¶

Get a PgxCsvFrameStorer instance for the PgxFrame

Return type: PgxCsvFrameStorer

db()¶

Get a PgxDbFrameStorer instance for the PgxFrame

Return type: PgxDbFrameStorer

format(format)¶

Create a specialized frame storer for saving the PgxFrame in a given format.

Parameters: format (str) – identifier of the wanted format. Can be one of ‘csv’, ‘pgb’ or ‘db’
Return type: PgxCsvFrameStorer, PgxPgbFrameStorer or PgxDbFrameStorer

name(frame_name)¶

Set the name of the stored frame.

Parameters: frame_name (str) – the new frame name
Returns: self
Return type: pypgx.api.frames._pgx_frame_storer.PgxGenericFrameStorer

overwrite(overwrite_bool)¶

Set overwrite

Parameters: overwrite_bool (bool) – denotes if the table should be overwritten.
Returns: self
Return type: pypgx.api.frames._pgx_frame_storer.PgxGenericFrameStorer

pgb()¶

Get a PgxPgbFrameStorer instance for the PgxFrame.

Return type: PgxPgbFrameStorer

class pypgx.api.frames.PgxPgbFrameReader(java_pgx_pgb_frame_reader)¶

Bases: object

Class for reading PgxFrame objects from PGB files.

Return type: None

auto_detect_columns(auto_detect)¶

Enable or disable the autodetection of columns from the table.

Executing this function clears the currently loaded column descriptors.

Parameters: auto_detect (bool) – True if the columns should be autodetected, False otherwise
Returns: self
Return type: pypgx.api.frames._pgx_frame_reader.PgxPgbFrameReader

clear_columns()¶

Clear the current configuration of which columns should be loaded and how.

Returns: None
Return type: None

columns(column_descriptors)¶

Set the columns to be loaded from their columnDescriptors.

Executing this function disables autodetection of columns.

Parameters: column_descriptors (List[Tuple[str, str]]) – List of tuples (columnName, columnType)
Returns: self
Return type: pypgx.api.frames._pgx_frame_reader.PgxPgbFrameReader

load(uris)¶

Load a PgxFrame from the provided URIs.

Parameters: uris (str) – the URIs from which to load the frame
Returns: PgxFrame instance
Return type: pypgx.api.frames._pgx_frame.PgxFrame

load_async(uris)¶

Load a PgxFrame from the provided URIs.

Parameters: uris (str) – the URIs from which to load the frame
Returns: PgxFrame instance

name(frame_name)¶

Set the frame name.

Parameters: frame_name (str) – New name for the PgxFrame
Returns: self
Return type: pypgx.api.frames._pgx_frame_reader.PgxPgbFrameReader

class pypgx.api.frames.PgxPgbFrameStorer(java_pgx_pgb_frame_storer)¶

Bases: object

Class for configuring the storing operation of a PgxFrame to a PGB file and then triggering it.

Return type: None

name(frame_name)¶

Set the frame name.

Parameters: frame_name (str) – frame name.
Returns: this storer
Return type: pypgx.api.frames._pgx_frame_storer.PgxPgbFrameStorer

overwrite(overwrite_bool)¶

Set overwrite

Parameters: overwrite_bool (bool) – denotes if the table should be overwritten.
Returns
Return type: pypgx.api.frames._pgx_frame_storer.PgxPgbFrameStorer

store()¶

Store PgxFrame

Returns: PgxFrame instance
Return type: None

store_async()¶

Store PgxFrame

Returns: PgxFrame instance

class pypgx.api.frames.VectorType(componenttype, dimension)¶

Bases: object

Represents a vector type which can be used in a PgxFrame.

Parameters

componenttype (str) –
dimension (int) –

Return type

None

get_value_type()¶

Get the type of component.

Returns: the component type
Return type: str

simple_string()¶

Get the string representation of a vector.

Returns: simple string of a vector
Return type: str