xgt.VertexFrame

class xgt.VertexFrame(conn, name, schema, key, error_frame_name)

VertexFrame object represents a collection of vertices held on the xGT server; it can be used to retrieve information about them and should not be instantiated directly by the user. Methods that return this object: Connection.get_vertex_frame(), Connection.get_vertex_frames() and Connection.create_vertex_frame().

Each vertex in a VertexFrame shares the same properties, described in VertexFrame.schema. Each vertex in a VertexFrame is uniquely identified by the property listed in VertexFrame.key.

Parameters

  • conn (Connection) – An open connection to an xGT server.

  • name (str) – Name of vertex frame.

  • schema (list of pairs) – List of pairs associating property names with xGT data types. Each vertex in the VertexFrame will have these properties.

  • key (str) – The property name used to uniquely identify vertices in the graph. This is the name of one of the properties from the schema and must be unique for each vertex in the frame.

  • error_frame_name (str) – Name of the frame created to store errors encountered while loading data. (internal)

Examples

>>> import xgt
>>> conn = xgt.Connection()
>>> v1 = conn.create_vertex_frame(
...        name = 'People',
...        schema = [['id', xgt.INT],
...                  ['name', xgt.TEXT]],
...        key = 'id')
>>> v2 = conn.get_vertex_frame('Companies') # An existing vertex frame
>>> print(v1.name, v2.name)
__init__(conn, name, schema, key, error_frame_name)

Initialize self. See help(type(self)) for accurate signature.

Methods

__init__(conn, name, schema, key, …)

Initialize self.

get_data([offset, length])

Returns frame data starting at a given offset and spanning a given length.

get_data_pandas([offset, length])

Returns a Pandas DataFrame containing frame data starting at a given offset and spanning a given length.

insert(data)

Inserts data rows.

load(paths[, headerMode])

Loads data from one or more CSV files specified in the list of paths.

save(path[, offset, length, headers])

Writes the rows from the frame to a CSV file in the path and the computer indicated by the path.

Attributes

error_frame_name

Name of the error table this frame will produce on errors.

key

Gets the property name that uniquely identifies vertices of this type.

name

Name of the table.

num_rows

Gets the number of vertices in the VertexFrame.

num_vertices

Gets the number of vertices in the VertexFrame.

schema

Gets the property names and types of the table.
property error_frame_name

Name of the error table this frame will produce on errors.

Type

str

get_data(offset=0, length=None)

Returns frame data starting at a given offset and spanning a given length.

Parameters

  • offset (int) – Position (index) of the first row to be retrieved. Optional. Default=0.

  • length (int) – Maximum number of rows to be retrieved starting from the row indicated by offset. A value of ‘None’ means ‘all rows’ on and after the offset. Optional. Default=None.

Returns

Return type

list of lists

get_data_pandas(offset=0, length=None)

Returns a Pandas DataFrame containing frame data starting at a given offset and spanning a given length.

Parameters

  • offset (int) – Position (index) of the first row to be retrieved. Optional. Default=0.

  • length (int) – Maximum number of rows to be retrieved starting from the row indicated by offset. A value of ‘None’ means ‘all rows’ on and after the offset. Optional. Default=None.

Returns

Return type

Pandas DataFrame

insert(data)

Inserts data rows. The properties of the new data must match the schema in both order and type.

Parameters

data (list or Pandas dataframe) – Data represented by a list of lists of data items or by a Pandas Dataframe.

property key

Gets the property name that uniquely identifies vertices of this type.

Type

str

load(paths, headerMode='none')

Loads data from one or more CSV files specified in the list of paths. Each path may have its own protocol as described below.

Parameters

  • paths (list) –

    Paths to the CSV files.

    Syntax for one CSV file path

    Resource type

    Path syntax

    local to python:

    ’<path to csv file>’ ‘xgt://<path to csv file>’

    xgtd computer:

    ’xgtd://<path to csv file>’

    AWS s3:

    ’s3://<path to csv file>’

    https site:

    ’https://<path to csv file>’

    http site:

    ’http://<path to csv file>’

    ftps server:

    ’ftps://<path to csv file>’

    ftp server:

    ’ftp://<path to csv file>’

  • headerMode (str) –

    Indicates if the files contain headers:

    • HeaderMode.NONE

    • HeaderMode.IGNORE

    • HeaderMode.NORMAL

    • HeaderMode.STRICT

    Optional. Default=HeaderMode.NONE.

property name

Name of the table.

Type

str

property num_rows

Gets the number of vertices in the VertexFrame.

Type

int

property num_vertices

Gets the number of vertices in the VertexFrame.

Type

int

save(path, offset=0, length=None, headers=False)

Writes the rows from the frame to a CSV file in the path and the computer indicated by the path.

Parameters

  • path (str) –

    Path to the CSV file.

    Syntax for one CSV file path

    Resource type

    Path syntax

    local to python:

    ’<path to csv file>’ ‘xgt://<path to csv file>’

    xgtd computer:

    ’xgtd://<path to csv file>’

  • offset (int) – Position (index) of the first row to be retrieved. Optional. Default=0.

  • length (int) – Maximum number of rows to be retrieved. Optional. Default=None.

  • headers (boolean) – Indicates if headers should be added. Optional. Default=False.

property schema

Gets the property names and types of the table.

Type

list of lists